freebsd-dev/module/zfs/zpl_xattr.c

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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (c) 2011, Lawrence Livermore National Security, LLC.
*
* Extended attributes (xattr) on Solaris are implemented as files
* which exist in a hidden xattr directory. These extended attributes
* can be accessed using the attropen() system call which opens
* the extended attribute. It can then be manipulated just like
* a standard file descriptor. This has a couple advantages such
* as practically no size limit on the file, and the extended
* attributes permissions may differ from those of the parent file.
* This interface is really quite clever, but it's also completely
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
* different than what is supported on Linux. It also comes with a
* steep performance penalty when accessing small xattrs because they
* are not stored with the parent file.
*
* Under Linux extended attributes are manipulated by the system
* calls getxattr(2), setxattr(2), and listxattr(2). They consider
* extended attributes to be name/value pairs where the name is a
* NULL terminated string. The name must also include one of the
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
* following namespace prefixes:
*
* user - No restrictions and is available to user applications.
* trusted - Restricted to kernel and root (CAP_SYS_ADMIN) use.
* system - Used for access control lists (system.nfs4_acl, etc).
* security - Used by SELinux to store a files security context.
*
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
* The value under Linux to limited to 65536 bytes of binary data.
* In practice, individual xattrs tend to be much smaller than this
* and are typically less than 100 bytes. A good example of this
* are the security.selinux xattrs which are less than 100 bytes and
* exist for every file when xattr labeling is enabled.
*
* The Linux xattr implementation has been written to take advantage of
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
* this typical usage. When the dataset property 'xattr=sa' is set,
* then xattrs will be preferentially stored as System Attributes (SA).
* This allows tiny xattrs (~100 bytes) to be stored with the dnode and
* up to 64k of xattrs to be stored in the spill block. If additional
* xattr space is required, which is unlikely under Linux, they will
* be stored using the traditional directory approach.
*
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
* This optimization results in roughly a 3x performance improvement
* when accessing xattrs because it avoids the need to perform a seek
* for every xattr value. When multiple xattrs are stored per-file
* the performance improvements are even greater because all of the
* xattrs stored in the spill block will be cached.
*
* However, by default SA based xattrs are disabled in the Linux port
* to maximize compatibility with other implementations. If you do
* enable SA based xattrs then they will not be visible on platforms
* which do not support this feature.
*
* NOTE: One additional consequence of the xattr directory implementation
* is that when an extended attribute is manipulated an inode is created.
* This inode will exist in the Linux inode cache but there will be no
* associated entry in the dentry cache which references it. This is
* safe but it may result in some confusion. Enabling SA based xattrs
* largely avoids the issue except in the overflow case.
*/
#include <sys/zfs_vfsops.h>
#include <sys/zfs_vnops.h>
#include <sys/zfs_znode.h>
#include <sys/zap.h>
#include <sys/vfs.h>
#include <sys/zpl.h>
typedef struct xattr_filldir {
size_t size;
size_t offset;
char *buf;
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
struct dentry *dentry;
} xattr_filldir_t;
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
static const struct xattr_handler *zpl_xattr_handler(const char *);
static int
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
zpl_xattr_permission(xattr_filldir_t *xf, const char *name, int name_len)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
static const struct xattr_handler *handler;
struct dentry *d = xf->dentry;
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
handler = zpl_xattr_handler(name);
if (!handler)
return (0);
if (handler->list) {
#if defined(HAVE_XATTR_LIST_SIMPLE)
if (!handler->list(d))
return (0);
#elif defined(HAVE_XATTR_LIST_DENTRY)
if (!handler->list(d, NULL, 0, name, name_len, 0))
return (0);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
#elif defined(HAVE_XATTR_LIST_HANDLER)
if (!handler->list(handler, d, NULL, 0, name, name_len))
return (0);
#elif defined(HAVE_XATTR_LIST_INODE)
if (!handler->list(d->d_inode, NULL, 0, name, name_len))
return (0);
#endif
}
return (1);
}
/*
* Determine is a given xattr name should be visible and if so copy it
* in to the provided buffer (xf->buf).
*/
static int
zpl_xattr_filldir(xattr_filldir_t *xf, const char *name, int name_len)
{
/* Check permissions using the per-namespace list xattr handler. */
if (!zpl_xattr_permission(xf, name, name_len))
return (0);
/* When xf->buf is NULL only calculate the required size. */
if (xf->buf) {
if (xf->offset + name_len + 1 > xf->size)
return (-ERANGE);
memcpy(xf->buf + xf->offset, name, name_len);
xf->buf[xf->offset + name_len] = '\0';
}
xf->offset += (name_len + 1);
return (0);
}
/*
* Read as many directory entry names as will fit in to the provided buffer,
* or when no buffer is provided calculate the required buffer size.
*/
int
zpl_xattr_readdir(struct inode *dxip, xattr_filldir_t *xf)
{
zap_cursor_t zc;
zap_attribute_t zap;
int error;
zap_cursor_init(&zc, ITOZSB(dxip)->z_os, ITOZ(dxip)->z_id);
while ((error = -zap_cursor_retrieve(&zc, &zap)) == 0) {
if (zap.za_integer_length != 8 || zap.za_num_integers != 1) {
error = -ENXIO;
break;
}
error = zpl_xattr_filldir(xf, zap.za_name, strlen(zap.za_name));
if (error)
break;
zap_cursor_advance(&zc);
}
zap_cursor_fini(&zc);
if (error == -ENOENT)
error = 0;
return (error);
}
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
static ssize_t
zpl_xattr_list_dir(xattr_filldir_t *xf, cred_t *cr)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
struct inode *ip = xf->dentry->d_inode;
struct inode *dxip = NULL;
int error;
/* Lookup the xattr directory */
error = -zfs_lookup(ip, NULL, &dxip, LOOKUP_XATTR, cr, NULL, NULL);
if (error) {
if (error == -ENOENT)
error = 0;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
return (error);
}
error = zpl_xattr_readdir(dxip, xf);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
iput(dxip);
return (error);
}
static ssize_t
zpl_xattr_list_sa(xattr_filldir_t *xf)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
znode_t *zp = ITOZ(xf->dentry->d_inode);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
nvpair_t *nvp = NULL;
int error = 0;
mutex_enter(&zp->z_lock);
if (zp->z_xattr_cached == NULL)
error = -zfs_sa_get_xattr(zp);
mutex_exit(&zp->z_lock);
if (error)
return (error);
ASSERT(zp->z_xattr_cached);
while ((nvp = nvlist_next_nvpair(zp->z_xattr_cached, nvp)) != NULL) {
ASSERT3U(nvpair_type(nvp), ==, DATA_TYPE_BYTE_ARRAY);
error = zpl_xattr_filldir(xf, nvpair_name(nvp),
strlen(nvpair_name(nvp)));
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
if (error)
return (error);
}
return (0);
}
ssize_t
zpl_xattr_list(struct dentry *dentry, char *buffer, size_t buffer_size)
{
znode_t *zp = ITOZ(dentry->d_inode);
zfsvfs_t *zfsvfs = ZTOZSB(zp);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
xattr_filldir_t xf = { buffer_size, 0, buffer, dentry };
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
cred_t *cr = CRED();
fstrans_cookie_t cookie;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
int error = 0;
crhold(cr);
cookie = spl_fstrans_mark();
rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
rw_enter(&zp->z_xattr_lock, RW_READER);
if (zfsvfs->z_use_sa && zp->z_is_sa) {
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_list_sa(&xf);
if (error)
goto out;
}
error = zpl_xattr_list_dir(&xf, cr);
if (error)
goto out;
error = xf.offset;
out:
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
rw_exit(&zp->z_xattr_lock);
rrm_exit(&(zfsvfs)->z_teardown_lock, FTAG);
spl_fstrans_unmark(cookie);
crfree(cr);
return (error);
}
static int
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
zpl_xattr_get_dir(struct inode *ip, const char *name, void *value,
size_t size, cred_t *cr)
{
struct inode *dxip = NULL;
struct inode *xip = NULL;
Linux AIO Support nfsd uses do_readv_writev() to implement fops->read and fops->write. do_readv_writev() will attempt to read/write using fops->aio_read and fops->aio_write, but it will fallback to fops->read and fops->write when AIO is not available. However, the fallback will perform a call for each individual data page. Since our default recordsize is 128KB, sequential operations on NFS will generate 32 DMU transactions where only 1 transaction was needed. That was unnecessary overhead and we implement fops->aio_read and fops->aio_write to eliminate it. ZFS originated in OpenSolaris, where the AIO API is entirely implemented in userland's libc by intelligently mapping them to VOP_WRITE, VOP_READ and VOP_FSYNC. Linux implements AIO inside the kernel itself. Linux filesystems therefore must implement their own AIO logic and nearly all of them implement fops->aio_write synchronously. Consequently, they do not implement aio_fsync(). However, since the ZPL works by mapping Linux's VFS calls to the functions implementing Illumos' VFS operations, we instead implement AIO in the kernel by mapping the operations to the VOP_READ, VOP_WRITE and VOP_FSYNC equivalents. We therefore implement fops->aio_fsync. One might be inclined to make our fops->aio_write implementation synchronous to make software that expects this behavior safe. However, there are several reasons not to do this: 1. Other platforms do not implement aio_write() synchronously and since the majority of userland software using AIO should be cross platform, expectations of synchronous behavior should not be a problem. 2. We would hurt the performance of programs that use POSIX interfaces properly while simultaneously encouraging the creation of more non-compliant software. 3. The broader community concluded that userland software should be patched to properly use POSIX interfaces instead of implementing hacks in filesystems to cater to broken software. This concept is best described as the O_PONIES debate. 4. Making an asynchronous write synchronous is non sequitur. Any software dependent on synchronous aio_write behavior will suffer data loss on ZFSOnLinux in a kernel panic / system failure of at most zfs_txg_timeout seconds, which by default is 5 seconds. This seems like a reasonable consequence of using non-compliant software. It should be noted that this is also a problem in the kernel itself where nfsd does not pass O_SYNC on files opened with it and instead relies on a open()/write()/close() to enforce synchronous behavior when the flush is only guarenteed on last close. Exporting any filesystem that does not implement AIO via NFS risks data loss in the event of a kernel panic / system failure when something else is also accessing the file. Exporting any file system that implements AIO the way this patch does bears similar risk. However, it seems reasonable to forgo crippling our AIO implementation in favor of developing patches to fix this problem in Linux's nfsd for the reasons stated earlier. In the interim, the risk will remain. Failing to implement AIO will not change the problem that nfsd created, so there is no reason for nfsd's mistake to block our implementation of AIO. It also should be noted that `aio_cancel()` will always return `AIO_NOTCANCELED` under this implementation. It is possible to implement aio_cancel by deferring work to taskqs and use `kiocb_set_cancel_fn()` to set a callback function for cancelling work sent to taskqs, but the simpler approach is allowed by the specification: ``` Which operations are cancelable is implementation-defined. ``` http://pubs.opengroup.org/onlinepubs/009695399/functions/aio_cancel.html The only programs on my system that are capable of using `aio_cancel()` are QEMU, beecrypt and fio use it according to a recursive grep of my system's `/usr/src/debug`. That suggests that `aio_cancel()` users are rare. Implementing aio_cancel() is left to a future date when it is clear that there are consumers that benefit from its implementation to justify the work. Lastly, it is important to know that handling of the iovec updates differs between Illumos and Linux in the implementation of read/write. On Linux, it is the VFS' responsibility whle on Illumos, it is the filesystem's responsibility. We take the intermediate solution of copying the iovec so that the ZFS code can update it like on Solaris while leaving the originals alone. This imposes some overhead. We could always revisit this should profiling show that the allocations are a problem. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #223 Closes #2373
2014-08-04 11:09:32 +00:00
loff_t pos = 0;
int error;
/* Lookup the xattr directory */
error = -zfs_lookup(ip, NULL, &dxip, LOOKUP_XATTR, cr, NULL, NULL);
if (error)
goto out;
/* Lookup a specific xattr name in the directory */
error = -zfs_lookup(dxip, (char *)name, &xip, 0, cr, NULL, NULL);
if (error)
goto out;
if (!size) {
error = i_size_read(xip);
goto out;
}
if (size < i_size_read(xip)) {
error = -ERANGE;
goto out;
}
Linux AIO Support nfsd uses do_readv_writev() to implement fops->read and fops->write. do_readv_writev() will attempt to read/write using fops->aio_read and fops->aio_write, but it will fallback to fops->read and fops->write when AIO is not available. However, the fallback will perform a call for each individual data page. Since our default recordsize is 128KB, sequential operations on NFS will generate 32 DMU transactions where only 1 transaction was needed. That was unnecessary overhead and we implement fops->aio_read and fops->aio_write to eliminate it. ZFS originated in OpenSolaris, where the AIO API is entirely implemented in userland's libc by intelligently mapping them to VOP_WRITE, VOP_READ and VOP_FSYNC. Linux implements AIO inside the kernel itself. Linux filesystems therefore must implement their own AIO logic and nearly all of them implement fops->aio_write synchronously. Consequently, they do not implement aio_fsync(). However, since the ZPL works by mapping Linux's VFS calls to the functions implementing Illumos' VFS operations, we instead implement AIO in the kernel by mapping the operations to the VOP_READ, VOP_WRITE and VOP_FSYNC equivalents. We therefore implement fops->aio_fsync. One might be inclined to make our fops->aio_write implementation synchronous to make software that expects this behavior safe. However, there are several reasons not to do this: 1. Other platforms do not implement aio_write() synchronously and since the majority of userland software using AIO should be cross platform, expectations of synchronous behavior should not be a problem. 2. We would hurt the performance of programs that use POSIX interfaces properly while simultaneously encouraging the creation of more non-compliant software. 3. The broader community concluded that userland software should be patched to properly use POSIX interfaces instead of implementing hacks in filesystems to cater to broken software. This concept is best described as the O_PONIES debate. 4. Making an asynchronous write synchronous is non sequitur. Any software dependent on synchronous aio_write behavior will suffer data loss on ZFSOnLinux in a kernel panic / system failure of at most zfs_txg_timeout seconds, which by default is 5 seconds. This seems like a reasonable consequence of using non-compliant software. It should be noted that this is also a problem in the kernel itself where nfsd does not pass O_SYNC on files opened with it and instead relies on a open()/write()/close() to enforce synchronous behavior when the flush is only guarenteed on last close. Exporting any filesystem that does not implement AIO via NFS risks data loss in the event of a kernel panic / system failure when something else is also accessing the file. Exporting any file system that implements AIO the way this patch does bears similar risk. However, it seems reasonable to forgo crippling our AIO implementation in favor of developing patches to fix this problem in Linux's nfsd for the reasons stated earlier. In the interim, the risk will remain. Failing to implement AIO will not change the problem that nfsd created, so there is no reason for nfsd's mistake to block our implementation of AIO. It also should be noted that `aio_cancel()` will always return `AIO_NOTCANCELED` under this implementation. It is possible to implement aio_cancel by deferring work to taskqs and use `kiocb_set_cancel_fn()` to set a callback function for cancelling work sent to taskqs, but the simpler approach is allowed by the specification: ``` Which operations are cancelable is implementation-defined. ``` http://pubs.opengroup.org/onlinepubs/009695399/functions/aio_cancel.html The only programs on my system that are capable of using `aio_cancel()` are QEMU, beecrypt and fio use it according to a recursive grep of my system's `/usr/src/debug`. That suggests that `aio_cancel()` users are rare. Implementing aio_cancel() is left to a future date when it is clear that there are consumers that benefit from its implementation to justify the work. Lastly, it is important to know that handling of the iovec updates differs between Illumos and Linux in the implementation of read/write. On Linux, it is the VFS' responsibility whle on Illumos, it is the filesystem's responsibility. We take the intermediate solution of copying the iovec so that the ZFS code can update it like on Solaris while leaving the originals alone. This imposes some overhead. We could always revisit this should profiling show that the allocations are a problem. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #223 Closes #2373
2014-08-04 11:09:32 +00:00
error = zpl_read_common(xip, value, size, &pos, UIO_SYSSPACE, 0, cr);
out:
if (xip)
iput(xip);
if (dxip)
iput(dxip);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
return (error);
}
static int
zpl_xattr_get_sa(struct inode *ip, const char *name, void *value, size_t size)
{
znode_t *zp = ITOZ(ip);
uchar_t *nv_value;
uint_t nv_size;
int error = 0;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
ASSERT(RW_LOCK_HELD(&zp->z_xattr_lock));
mutex_enter(&zp->z_lock);
if (zp->z_xattr_cached == NULL)
error = -zfs_sa_get_xattr(zp);
mutex_exit(&zp->z_lock);
if (error)
return (error);
ASSERT(zp->z_xattr_cached);
error = -nvlist_lookup_byte_array(zp->z_xattr_cached, name,
&nv_value, &nv_size);
if (error)
return (error);
if (!size)
return (nv_size);
if (size < nv_size)
return (-ERANGE);
memcpy(value, nv_value, nv_size);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
return (nv_size);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
}
static int
__zpl_xattr_get(struct inode *ip, const char *name, void *value, size_t size,
cred_t *cr)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ZTOZSB(zp);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
int error;
ASSERT(RW_LOCK_HELD(&zp->z_xattr_lock));
if (zfsvfs->z_use_sa && zp->z_is_sa) {
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_get_sa(ip, name, value, size);
if (error != -ENOENT)
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
goto out;
}
error = zpl_xattr_get_dir(ip, name, value, size, cr);
out:
if (error == -ENOENT)
error = -ENODATA;
return (error);
}
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
#define XATTR_NOENT 0x0
#define XATTR_IN_SA 0x1
#define XATTR_IN_DIR 0x2
/* check where the xattr resides */
static int
__zpl_xattr_where(struct inode *ip, const char *name, int *where, cred_t *cr)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ZTOZSB(zp);
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
int error;
ASSERT(where);
ASSERT(RW_LOCK_HELD(&zp->z_xattr_lock));
*where = XATTR_NOENT;
if (zfsvfs->z_use_sa && zp->z_is_sa) {
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
error = zpl_xattr_get_sa(ip, name, NULL, 0);
if (error >= 0)
*where |= XATTR_IN_SA;
else if (error != -ENOENT)
return (error);
}
error = zpl_xattr_get_dir(ip, name, NULL, 0, cr);
if (error >= 0)
*where |= XATTR_IN_DIR;
else if (error != -ENOENT)
return (error);
if (*where == (XATTR_IN_SA|XATTR_IN_DIR))
cmn_err(CE_WARN, "ZFS: inode %p has xattr \"%s\""
" in both SA and dir", ip, name);
if (*where == XATTR_NOENT)
error = -ENODATA;
else
error = 0;
return (error);
}
static int
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
zpl_xattr_get(struct inode *ip, const char *name, void *value, size_t size)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ZTOZSB(zp);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
cred_t *cr = CRED();
fstrans_cookie_t cookie;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
int error;
crhold(cr);
cookie = spl_fstrans_mark();
rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
rw_enter(&zp->z_xattr_lock, RW_READER);
error = __zpl_xattr_get(ip, name, value, size, cr);
rw_exit(&zp->z_xattr_lock);
rrm_exit(&(zfsvfs)->z_teardown_lock, FTAG);
spl_fstrans_unmark(cookie);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
crfree(cr);
return (error);
}
static int
zpl_xattr_set_dir(struct inode *ip, const char *name, const void *value,
size_t size, int flags, cred_t *cr)
{
struct inode *dxip = NULL;
struct inode *xip = NULL;
vattr_t *vap = NULL;
ssize_t wrote;
int lookup_flags, error;
const int xattr_mode = S_IFREG | 0644;
Linux AIO Support nfsd uses do_readv_writev() to implement fops->read and fops->write. do_readv_writev() will attempt to read/write using fops->aio_read and fops->aio_write, but it will fallback to fops->read and fops->write when AIO is not available. However, the fallback will perform a call for each individual data page. Since our default recordsize is 128KB, sequential operations on NFS will generate 32 DMU transactions where only 1 transaction was needed. That was unnecessary overhead and we implement fops->aio_read and fops->aio_write to eliminate it. ZFS originated in OpenSolaris, where the AIO API is entirely implemented in userland's libc by intelligently mapping them to VOP_WRITE, VOP_READ and VOP_FSYNC. Linux implements AIO inside the kernel itself. Linux filesystems therefore must implement their own AIO logic and nearly all of them implement fops->aio_write synchronously. Consequently, they do not implement aio_fsync(). However, since the ZPL works by mapping Linux's VFS calls to the functions implementing Illumos' VFS operations, we instead implement AIO in the kernel by mapping the operations to the VOP_READ, VOP_WRITE and VOP_FSYNC equivalents. We therefore implement fops->aio_fsync. One might be inclined to make our fops->aio_write implementation synchronous to make software that expects this behavior safe. However, there are several reasons not to do this: 1. Other platforms do not implement aio_write() synchronously and since the majority of userland software using AIO should be cross platform, expectations of synchronous behavior should not be a problem. 2. We would hurt the performance of programs that use POSIX interfaces properly while simultaneously encouraging the creation of more non-compliant software. 3. The broader community concluded that userland software should be patched to properly use POSIX interfaces instead of implementing hacks in filesystems to cater to broken software. This concept is best described as the O_PONIES debate. 4. Making an asynchronous write synchronous is non sequitur. Any software dependent on synchronous aio_write behavior will suffer data loss on ZFSOnLinux in a kernel panic / system failure of at most zfs_txg_timeout seconds, which by default is 5 seconds. This seems like a reasonable consequence of using non-compliant software. It should be noted that this is also a problem in the kernel itself where nfsd does not pass O_SYNC on files opened with it and instead relies on a open()/write()/close() to enforce synchronous behavior when the flush is only guarenteed on last close. Exporting any filesystem that does not implement AIO via NFS risks data loss in the event of a kernel panic / system failure when something else is also accessing the file. Exporting any file system that implements AIO the way this patch does bears similar risk. However, it seems reasonable to forgo crippling our AIO implementation in favor of developing patches to fix this problem in Linux's nfsd for the reasons stated earlier. In the interim, the risk will remain. Failing to implement AIO will not change the problem that nfsd created, so there is no reason for nfsd's mistake to block our implementation of AIO. It also should be noted that `aio_cancel()` will always return `AIO_NOTCANCELED` under this implementation. It is possible to implement aio_cancel by deferring work to taskqs and use `kiocb_set_cancel_fn()` to set a callback function for cancelling work sent to taskqs, but the simpler approach is allowed by the specification: ``` Which operations are cancelable is implementation-defined. ``` http://pubs.opengroup.org/onlinepubs/009695399/functions/aio_cancel.html The only programs on my system that are capable of using `aio_cancel()` are QEMU, beecrypt and fio use it according to a recursive grep of my system's `/usr/src/debug`. That suggests that `aio_cancel()` users are rare. Implementing aio_cancel() is left to a future date when it is clear that there are consumers that benefit from its implementation to justify the work. Lastly, it is important to know that handling of the iovec updates differs between Illumos and Linux in the implementation of read/write. On Linux, it is the VFS' responsibility whle on Illumos, it is the filesystem's responsibility. We take the intermediate solution of copying the iovec so that the ZFS code can update it like on Solaris while leaving the originals alone. This imposes some overhead. We could always revisit this should profiling show that the allocations are a problem. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #223 Closes #2373
2014-08-04 11:09:32 +00:00
loff_t pos = 0;
/*
* Lookup the xattr directory. When we're adding an entry pass
* CREATE_XATTR_DIR to ensure the xattr directory is created.
* When removing an entry this flag is not passed to avoid
* unnecessarily creating a new xattr directory.
*/
lookup_flags = LOOKUP_XATTR;
if (value != NULL)
lookup_flags |= CREATE_XATTR_DIR;
error = -zfs_lookup(ip, NULL, &dxip, lookup_flags, cr, NULL, NULL);
if (error)
goto out;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
/* Lookup a specific xattr name in the directory */
error = -zfs_lookup(dxip, (char *)name, &xip, 0, cr, NULL, NULL);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
if (error && (error != -ENOENT))
goto out;
error = 0;
/* Remove a specific name xattr when value is set to NULL. */
if (value == NULL) {
if (xip)
error = -zfs_remove(dxip, (char *)name, cr, 0);
goto out;
}
/* Lookup failed create a new xattr. */
if (xip == NULL) {
vap = kmem_zalloc(sizeof (vattr_t), KM_SLEEP);
vap->va_mode = xattr_mode;
vap->va_mask = ATTR_MODE;
vap->va_uid = crgetfsuid(cr);
vap->va_gid = crgetfsgid(cr);
error = -zfs_create(dxip, (char *)name, vap, 0, 0644, &xip,
cr, 0, NULL);
if (error)
goto out;
}
ASSERT(xip != NULL);
error = -zfs_freesp(ITOZ(xip), 0, 0, xattr_mode, TRUE);
if (error)
goto out;
Linux AIO Support nfsd uses do_readv_writev() to implement fops->read and fops->write. do_readv_writev() will attempt to read/write using fops->aio_read and fops->aio_write, but it will fallback to fops->read and fops->write when AIO is not available. However, the fallback will perform a call for each individual data page. Since our default recordsize is 128KB, sequential operations on NFS will generate 32 DMU transactions where only 1 transaction was needed. That was unnecessary overhead and we implement fops->aio_read and fops->aio_write to eliminate it. ZFS originated in OpenSolaris, where the AIO API is entirely implemented in userland's libc by intelligently mapping them to VOP_WRITE, VOP_READ and VOP_FSYNC. Linux implements AIO inside the kernel itself. Linux filesystems therefore must implement their own AIO logic and nearly all of them implement fops->aio_write synchronously. Consequently, they do not implement aio_fsync(). However, since the ZPL works by mapping Linux's VFS calls to the functions implementing Illumos' VFS operations, we instead implement AIO in the kernel by mapping the operations to the VOP_READ, VOP_WRITE and VOP_FSYNC equivalents. We therefore implement fops->aio_fsync. One might be inclined to make our fops->aio_write implementation synchronous to make software that expects this behavior safe. However, there are several reasons not to do this: 1. Other platforms do not implement aio_write() synchronously and since the majority of userland software using AIO should be cross platform, expectations of synchronous behavior should not be a problem. 2. We would hurt the performance of programs that use POSIX interfaces properly while simultaneously encouraging the creation of more non-compliant software. 3. The broader community concluded that userland software should be patched to properly use POSIX interfaces instead of implementing hacks in filesystems to cater to broken software. This concept is best described as the O_PONIES debate. 4. Making an asynchronous write synchronous is non sequitur. Any software dependent on synchronous aio_write behavior will suffer data loss on ZFSOnLinux in a kernel panic / system failure of at most zfs_txg_timeout seconds, which by default is 5 seconds. This seems like a reasonable consequence of using non-compliant software. It should be noted that this is also a problem in the kernel itself where nfsd does not pass O_SYNC on files opened with it and instead relies on a open()/write()/close() to enforce synchronous behavior when the flush is only guarenteed on last close. Exporting any filesystem that does not implement AIO via NFS risks data loss in the event of a kernel panic / system failure when something else is also accessing the file. Exporting any file system that implements AIO the way this patch does bears similar risk. However, it seems reasonable to forgo crippling our AIO implementation in favor of developing patches to fix this problem in Linux's nfsd for the reasons stated earlier. In the interim, the risk will remain. Failing to implement AIO will not change the problem that nfsd created, so there is no reason for nfsd's mistake to block our implementation of AIO. It also should be noted that `aio_cancel()` will always return `AIO_NOTCANCELED` under this implementation. It is possible to implement aio_cancel by deferring work to taskqs and use `kiocb_set_cancel_fn()` to set a callback function for cancelling work sent to taskqs, but the simpler approach is allowed by the specification: ``` Which operations are cancelable is implementation-defined. ``` http://pubs.opengroup.org/onlinepubs/009695399/functions/aio_cancel.html The only programs on my system that are capable of using `aio_cancel()` are QEMU, beecrypt and fio use it according to a recursive grep of my system's `/usr/src/debug`. That suggests that `aio_cancel()` users are rare. Implementing aio_cancel() is left to a future date when it is clear that there are consumers that benefit from its implementation to justify the work. Lastly, it is important to know that handling of the iovec updates differs between Illumos and Linux in the implementation of read/write. On Linux, it is the VFS' responsibility whle on Illumos, it is the filesystem's responsibility. We take the intermediate solution of copying the iovec so that the ZFS code can update it like on Solaris while leaving the originals alone. This imposes some overhead. We could always revisit this should profiling show that the allocations are a problem. Signed-off-by: Richard Yao <ryao@gentoo.org> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #223 Closes #2373
2014-08-04 11:09:32 +00:00
wrote = zpl_write_common(xip, value, size, &pos, UIO_SYSSPACE, 0, cr);
if (wrote < 0)
error = wrote;
out:
if (vap)
kmem_free(vap, sizeof (vattr_t));
if (xip)
iput(xip);
if (dxip)
iput(dxip);
if (error == -ENOENT)
error = -ENODATA;
ASSERT3S(error, <=, 0);
return (error);
}
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
static int
zpl_xattr_set_sa(struct inode *ip, const char *name, const void *value,
size_t size, int flags, cred_t *cr)
{
znode_t *zp = ITOZ(ip);
nvlist_t *nvl;
size_t sa_size;
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
int error = 0;
mutex_enter(&zp->z_lock);
if (zp->z_xattr_cached == NULL)
error = -zfs_sa_get_xattr(zp);
mutex_exit(&zp->z_lock);
if (error)
return (error);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
ASSERT(zp->z_xattr_cached);
nvl = zp->z_xattr_cached;
if (value == NULL) {
error = -nvlist_remove(nvl, name, DATA_TYPE_BYTE_ARRAY);
if (error == -ENOENT)
error = zpl_xattr_set_dir(ip, name, NULL, 0, flags, cr);
} else {
/* Limited to 32k to keep nvpair memory allocations small */
if (size > DXATTR_MAX_ENTRY_SIZE)
return (-EFBIG);
/* Prevent the DXATTR SA from consuming the entire SA region */
error = -nvlist_size(nvl, &sa_size, NV_ENCODE_XDR);
if (error)
return (error);
if (sa_size > DXATTR_MAX_SA_SIZE)
return (-EFBIG);
error = -nvlist_add_byte_array(nvl, name,
(uchar_t *)value, size);
}
/*
* Update the SA for additions, modifications, and removals. On
* error drop the inconsistent cached version of the nvlist, it
* will be reconstructed from the ARC when next accessed.
*/
if (error == 0)
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = -zfs_sa_set_xattr(zp);
if (error) {
nvlist_free(nvl);
zp->z_xattr_cached = NULL;
}
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
ASSERT3S(error, <=, 0);
return (error);
}
static int
zpl_xattr_set(struct inode *ip, const char *name, const void *value,
size_t size, int flags)
{
znode_t *zp = ITOZ(ip);
zfsvfs_t *zfsvfs = ZTOZSB(zp);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
cred_t *cr = CRED();
fstrans_cookie_t cookie;
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
int where;
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
int error;
crhold(cr);
cookie = spl_fstrans_mark();
rrm_enter_read(&(zfsvfs)->z_teardown_lock, FTAG);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
rw_enter(&ITOZ(ip)->z_xattr_lock, RW_WRITER);
/*
* Before setting the xattr check to see if it already exists.
* This is done to ensure the following optional flags are honored.
*
* XATTR_CREATE: fail if xattr already exists
* XATTR_REPLACE: fail if xattr does not exist
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
*
* We also want to know if it resides in sa or dir, so we can make
* sure we don't end up with duplicate in both places.
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
*/
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
error = __zpl_xattr_where(ip, name, &where, cr);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
if (error < 0) {
if (error != -ENODATA)
goto out;
if (flags & XATTR_REPLACE)
goto out;
/* The xattr to be removed already doesn't exist */
error = 0;
if (value == NULL)
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
goto out;
} else {
error = -EEXIST;
if (flags & XATTR_CREATE)
goto out;
}
/* Preferentially store the xattr as a SA for better performance */
if (zfsvfs->z_use_sa && zp->z_is_sa &&
(zfsvfs->z_xattr_sa || (value == NULL && where & XATTR_IN_SA))) {
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_set_sa(ip, name, value, size, flags, cr);
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
if (error == 0) {
/*
* Successfully put into SA, we need to clear the one
* in dir.
*/
if (where & XATTR_IN_DIR)
zpl_xattr_set_dir(ip, name, NULL, 0, 0, cr);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
goto out;
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
}
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
}
error = zpl_xattr_set_dir(ip, name, value, size, flags, cr);
Prevent duplicated xattr between SA and dir When replacing an xattr would cause overflowing in SA, we would fallback to xattr dir. However, current implementation don't clear the one in SA, so we would end up with duplicated SA. For example, running the following script on an xattr=sa filesystem would cause duplicated "user.1". -- dup_xattr.sh begin -- randbase64() { dd if=/dev/urandom bs=1 count=$1 2>/dev/null | openssl enc -a -A } file=$1 touch $file setfattr -h -n user.1 -v `randbase64 5000` $file setfattr -h -n user.2 -v `randbase64 20000` $file setfattr -h -n user.3 -v `randbase64 20000` $file setfattr -h -n user.1 -v `randbase64 20000` $file getfattr -m. -d $file -- dup_xattr.sh end -- Also, when a filesystem is switch from xattr=sa to xattr=on, it will never modify those in SA. This would cause strange behavior like, you cannot delete an xattr, or setxattr would cause duplicate and the result would not match when you getxattr. For example, the following shell sequence. -- shell begin -- $ sudo zfs set xattr=sa pp/fs0 $ touch zzz $ setfattr -n user.test -v asdf zzz $ sudo zfs set xattr=on pp/fs0 $ setfattr -x user.test zzz setfattr: zzz: No such attribute $ getfattr -d zzz user.test="asdf" $ setfattr -n user.test -v zxcv zzz $ getfattr -d zzz user.test="asdf" user.test="asdf" -- shell end -- We fix this behavior, by first finding where the xattr resides before setxattr. Then, after we successfully updated the xattr in one location, we will clear the other location. Note that, because update and clear are not in single tx, we could still end up with duplicated xattr. But by doing setxattr again, it can be fixed. Signed-off-by: Chunwei Chen <david.chen@osnexus.com> Closes #3472 Closes #4153
2015-12-30 23:47:11 +00:00
/*
* Successfully put into dir, we need to clear the one in SA.
*/
if (error == 0 && (where & XATTR_IN_SA))
zpl_xattr_set_sa(ip, name, NULL, 0, 0, cr);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
out:
rw_exit(&ITOZ(ip)->z_xattr_lock);
rrm_exit(&(zfsvfs)->z_teardown_lock, FTAG);
spl_fstrans_unmark(cookie);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
crfree(cr);
ASSERT3S(error, <=, 0);
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* Extended user attributes
*
* "Extended user attributes may be assigned to files and directories for
* storing arbitrary additional information such as the mime type,
* character set or encoding of a file. The access permissions for user
* attributes are defined by the file permission bits: read permission
* is required to retrieve the attribute value, and writer permission is
* required to change it.
*
* The file permission bits of regular files and directories are
* interpreted differently from the file permission bits of special
* files and symbolic links. For regular files and directories the file
* permission bits define access to the file's contents, while for
* device special files they define access to the device described by
* the special file. The file permissions of symbolic links are not
* used in access checks. These differences would allow users to
* consume filesystem resources in a way not controllable by disk quotas
* for group or world writable special files and directories.
*
* For this reason, extended user attributes are allowed only for
* regular files and directories, and access to extended user attributes
* is restricted to the owner and to users with appropriate capabilities
* for directories with the sticky bit set (see the chmod(1) manual page
* for an explanation of the sticky bit)." - xattr(7)
*
* ZFS allows extended user attributes to be disabled administratively
* by setting the 'xattr=off' property on the dataset.
*/
static int
__zpl_xattr_user_list(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
return (ITOZSB(ip)->z_flags & ZSB_XATTR);
}
ZPL_XATTR_LIST_WRAPPER(zpl_xattr_user_list);
static int
__zpl_xattr_user_get(struct inode *ip, const char *name,
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
void *value, size_t size)
{
char *xattr_name;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
Linux compat 2.6.39: mount_nodev() The .get_sb callback has been replaced by a .mount callback in the file_system_type structure. When using the new interface the caller must now use the mount_nodev() helper. Unfortunately, the new interface no longer passes the vfsmount down to the zfs layers. This poses a problem for the existing implementation because we currently save this pointer in the super block for latter use. It provides our only entry point in to the namespace layer for manipulating certain mount options. This needed to be done originally to allow commands like 'zfs set atime=off tank' to work properly. It also allowed me to keep more of the original Solaris code unmodified. Under Solaris there is a 1-to-1 mapping between a mount point and a file system so this is a fairly natural thing to do. However, under Linux they many be multiple entries in the namespace which reference the same filesystem. Thus keeping a back reference from the filesystem to the namespace is complicated. Rather than introduce some ugly hack to get the vfsmount and continue as before. I'm leveraging this API change to update the ZFS code to do things in a more natural way for Linux. This has the upside that is resolves the compatibility issue for the long term and fixes several other minor bugs which have been reported. This commit updates the code to remove this vfsmount back reference entirely. All modifications to filesystem mount options are now passed in to the kernel via a '-o remount'. This is the expected Linux mechanism and allows the namespace to properly handle any options which apply to it before passing them on to the file system itself. Aside from fixing the compatibility issue, removing the vfsmount has had the benefit of simplifying the code. This change which fairly involved has turned out nicely. Closes #246 Closes #217 Closes #187 Closes #248 Closes #231
2011-05-19 18:44:07 +00:00
if (!(ITOZSB(ip)->z_flags & ZSB_XATTR))
return (-EOPNOTSUPP);
xattr_name = kmem_asprintf("%s%s", XATTR_USER_PREFIX, name);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_get(ip, xattr_name, value, size);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_GET_WRAPPER(zpl_xattr_user_get);
static int
__zpl_xattr_user_set(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
char *xattr_name;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
Linux compat 2.6.39: mount_nodev() The .get_sb callback has been replaced by a .mount callback in the file_system_type structure. When using the new interface the caller must now use the mount_nodev() helper. Unfortunately, the new interface no longer passes the vfsmount down to the zfs layers. This poses a problem for the existing implementation because we currently save this pointer in the super block for latter use. It provides our only entry point in to the namespace layer for manipulating certain mount options. This needed to be done originally to allow commands like 'zfs set atime=off tank' to work properly. It also allowed me to keep more of the original Solaris code unmodified. Under Solaris there is a 1-to-1 mapping between a mount point and a file system so this is a fairly natural thing to do. However, under Linux they many be multiple entries in the namespace which reference the same filesystem. Thus keeping a back reference from the filesystem to the namespace is complicated. Rather than introduce some ugly hack to get the vfsmount and continue as before. I'm leveraging this API change to update the ZFS code to do things in a more natural way for Linux. This has the upside that is resolves the compatibility issue for the long term and fixes several other minor bugs which have been reported. This commit updates the code to remove this vfsmount back reference entirely. All modifications to filesystem mount options are now passed in to the kernel via a '-o remount'. This is the expected Linux mechanism and allows the namespace to properly handle any options which apply to it before passing them on to the file system itself. Aside from fixing the compatibility issue, removing the vfsmount has had the benefit of simplifying the code. This change which fairly involved has turned out nicely. Closes #246 Closes #217 Closes #187 Closes #248 Closes #231
2011-05-19 18:44:07 +00:00
if (!(ITOZSB(ip)->z_flags & ZSB_XATTR))
return (-EOPNOTSUPP);
xattr_name = kmem_asprintf("%s%s", XATTR_USER_PREFIX, name);
error = zpl_xattr_set(ip, xattr_name, value, size, flags);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_SET_WRAPPER(zpl_xattr_user_set);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
xattr_handler_t zpl_xattr_user_handler =
{
.prefix = XATTR_USER_PREFIX,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
.list = zpl_xattr_user_list,
.get = zpl_xattr_user_get,
.set = zpl_xattr_user_set,
};
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* Trusted extended attributes
*
* "Trusted extended attributes are visible and accessible only to
* processes that have the CAP_SYS_ADMIN capability. Attributes in this
* class are used to implement mechanisms in user space (i.e., outside
* the kernel) which keep information in extended attributes to which
* ordinary processes should not have access." - xattr(7)
*/
static int
__zpl_xattr_trusted_list(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
return (capable(CAP_SYS_ADMIN));
}
ZPL_XATTR_LIST_WRAPPER(zpl_xattr_trusted_list);
static int
__zpl_xattr_trusted_get(struct inode *ip, const char *name,
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
void *value, size_t size)
{
char *xattr_name;
int error;
if (!capable(CAP_SYS_ADMIN))
return (-EACCES);
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
xattr_name = kmem_asprintf("%s%s", XATTR_TRUSTED_PREFIX, name);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_get(ip, xattr_name, value, size);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_GET_WRAPPER(zpl_xattr_trusted_get);
static int
__zpl_xattr_trusted_set(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
char *xattr_name;
int error;
if (!capable(CAP_SYS_ADMIN))
return (-EACCES);
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
xattr_name = kmem_asprintf("%s%s", XATTR_TRUSTED_PREFIX, name);
error = zpl_xattr_set(ip, xattr_name, value, size, flags);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_SET_WRAPPER(zpl_xattr_trusted_set);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
xattr_handler_t zpl_xattr_trusted_handler =
{
.prefix = XATTR_TRUSTED_PREFIX,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
.list = zpl_xattr_trusted_list,
.get = zpl_xattr_trusted_get,
.set = zpl_xattr_trusted_set,
};
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* Extended security attributes
*
* "The security attribute namespace is used by kernel security modules,
* such as Security Enhanced Linux, and also to implement file
* capabilities (see capabilities(7)). Read and write access
* permissions to security attributes depend on the policy implemented
* for each security attribute by the security module. When no security
* module is loaded, all processes have read access to extended security
* attributes, and write access is limited to processes that have the
* CAP_SYS_ADMIN capability." - xattr(7)
*/
static int
__zpl_xattr_security_list(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
return (1);
}
ZPL_XATTR_LIST_WRAPPER(zpl_xattr_security_list);
static int
__zpl_xattr_security_get(struct inode *ip, const char *name,
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
void *value, size_t size)
{
char *xattr_name;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
xattr_name = kmem_asprintf("%s%s", XATTR_SECURITY_PREFIX, name);
Implement SA based xattrs The current ZFS implementation stores xattrs on disk using a hidden directory. In this directory a file name represents the xattr name and the file contexts are the xattr binary data. This approach is very flexible and allows for arbitrarily large xattrs. However, it also suffers from a significant performance penalty. Accessing a single xattr can requires up to three disk seeks. 1) Lookup the dnode object. 2) Lookup the dnodes's xattr directory object. 3) Lookup the xattr object in the directory. To avoid this performance penalty Linux filesystems such as ext3 and xfs try to store the xattr as part of the inode on disk. When the xattr is to large to store in the inode then a single external block is allocated for them. In practice most xattrs are small and this approach works well. The addition of System Attributes (SA) to zfs provides us a clean way to make this optimization. When the dataset property 'xattr=sa' is set then xattrs will be preferentially stored as System Attributes. This allows tiny xattrs (~100 bytes) to be stored with the dnode and up to 64k of xattrs to be stored in the spill block. If additional xattr space is required, which is unlikely under Linux, they will be stored using the traditional directory approach. This optimization results in roughly a 3x performance improvement when accessing xattrs which brings zfs roughly to parity with ext4 and xfs (see table below). When multiple xattrs are stored per-file the performance improvements are even greater because all of the xattrs stored in the spill block will be cached. However, by default SA based xattrs are disabled in the Linux port to maximize compatibility with other implementations. If you do enable SA based xattrs then they will not be visible on platforms which do not support this feature. ---------------------------------------------------------------------- Time in seconds to get/set one xattr of N bytes on 100,000 files ------+--------------------------------+------------------------------ | setxattr | getxattr bytes | ext4 xfs zfs-dir zfs-sa | ext4 xfs zfs-dir zfs-sa ------+--------------------------------+------------------------------ 1 | 2.33 31.88 21.50 4.57 | 2.35 2.64 6.29 2.43 32 | 2.79 30.68 21.98 4.60 | 2.44 2.59 6.78 2.48 256 | 3.25 31.99 21.36 5.92 | 2.32 2.71 6.22 3.14 1024 | 3.30 32.61 22.83 8.45 | 2.40 2.79 6.24 3.27 4096 | 3.57 317.46 22.52 10.73 | 2.78 28.62 6.90 3.94 16384 | n/a 2342.39 34.30 19.20 | n/a 45.44 145.90 7.55 65536 | n/a 2941.39 128.15 131.32* | n/a 141.92 256.85 262.12* Legend: * ext4 - Stock RHEL6.1 ext4 mounted with '-o user_xattr'. * xfs - Stock RHEL6.1 xfs mounted with default options. * zfs-dir - Directory based xattrs only. * zfs-sa - Prefer SAs but spill in to directories as needed, a trailing * indicates overflow in to directories occured. NOTE: Ext4 supports 4096 bytes of xattr name/value pairs per file. NOTE: XFS and ZFS have no limit on xattr name/value pairs per file. NOTE: Linux limits individual name/value pairs to 65536 bytes. NOTE: All setattr/getattr's were done after dropping the cache. NOTE: All tests were run against a single hard drive. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Issue #443
2011-10-24 23:55:20 +00:00
error = zpl_xattr_get(ip, xattr_name, value, size);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_GET_WRAPPER(zpl_xattr_security_get);
static int
__zpl_xattr_security_set(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
char *xattr_name;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") == 0)
return (-EINVAL);
#endif
xattr_name = kmem_asprintf("%s%s", XATTR_SECURITY_PREFIX, name);
error = zpl_xattr_set(ip, xattr_name, value, size, flags);
strfree(xattr_name);
return (error);
}
ZPL_XATTR_SET_WRAPPER(zpl_xattr_security_set);
#ifdef HAVE_CALLBACK_SECURITY_INODE_INIT_SECURITY
static int
__zpl_xattr_security_init(struct inode *ip, const struct xattr *xattrs,
void *fs_info)
{
const struct xattr *xattr;
int error = 0;
for (xattr = xattrs; xattr->name != NULL; xattr++) {
error = __zpl_xattr_security_set(ip,
xattr->name, xattr->value, xattr->value_len, 0);
if (error < 0)
break;
}
return (error);
}
int
zpl_xattr_security_init(struct inode *ip, struct inode *dip,
const struct qstr *qstr)
{
return security_inode_init_security(ip, dip, qstr,
&__zpl_xattr_security_init, NULL);
}
#else
int
zpl_xattr_security_init(struct inode *ip, struct inode *dip,
const struct qstr *qstr)
{
int error;
size_t len;
void *value;
char *name;
error = zpl_security_inode_init_security(ip, dip, qstr,
&name, &value, &len);
if (error) {
if (error == -EOPNOTSUPP)
return (0);
return (error);
}
error = __zpl_xattr_security_set(ip, name, value, len, 0);
kfree(name);
kfree(value);
return (error);
}
#endif /* HAVE_CALLBACK_SECURITY_INODE_INIT_SECURITY */
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* Security xattr namespace handlers.
*/
xattr_handler_t zpl_xattr_security_handler = {
.prefix = XATTR_SECURITY_PREFIX,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
.list = zpl_xattr_security_list,
.get = zpl_xattr_security_get,
.set = zpl_xattr_security_set,
};
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* Extended system attributes
*
* "Extended system attributes are used by the kernel to store system
* objects such as Access Control Lists. Read and write access permissions
* to system attributes depend on the policy implemented for each system
* attribute implemented by filesystems in the kernel." - xattr(7)
*/
#ifdef CONFIG_FS_POSIX_ACL
int
zpl_set_acl(struct inode *ip, struct posix_acl *acl, int type)
{
char *name, *value = NULL;
int error = 0;
size_t size = 0;
if (S_ISLNK(ip->i_mode))
return (-EOPNOTSUPP);
switch (type) {
case ACL_TYPE_ACCESS:
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
name = XATTR_NAME_POSIX_ACL_ACCESS;
if (acl) {
zpl_equivmode_t mode = ip->i_mode;
error = posix_acl_equiv_mode(acl, &mode);
if (error < 0) {
return (error);
} else {
/*
* The mode bits will have been set by
* ->zfs_setattr()->zfs_acl_chmod_setattr()
* using the ZFS ACL conversion. If they
* differ from the Posix ACL conversion dirty
* the inode to write the Posix mode bits.
*/
if (ip->i_mode != mode) {
ip->i_mode = mode;
ip->i_ctime = current_time(ip);
zfs_mark_inode_dirty(ip);
}
if (error == 0)
acl = NULL;
}
}
break;
case ACL_TYPE_DEFAULT:
name = XATTR_NAME_POSIX_ACL_DEFAULT;
if (!S_ISDIR(ip->i_mode))
return (acl ? -EACCES : 0);
break;
default:
return (-EINVAL);
}
if (acl) {
size = posix_acl_xattr_size(acl->a_count);
value = kmem_alloc(size, KM_SLEEP);
error = zpl_acl_to_xattr(acl, value, size);
if (error < 0) {
kmem_free(value, size);
return (error);
}
}
error = zpl_xattr_set(ip, name, value, size, 0);
if (value)
kmem_free(value, size);
if (!error) {
if (acl)
zpl_set_cached_acl(ip, type, acl);
else
zpl_forget_cached_acl(ip, type);
}
return (error);
}
struct posix_acl *
zpl_get_acl(struct inode *ip, int type)
{
struct posix_acl *acl;
void *value = NULL;
char *name;
int size;
/*
* As of Linux 3.14, the kernel get_acl will check this for us.
* Also as of Linux 4.7, comparing against ACL_NOT_CACHED is wrong
* as the kernel get_acl will set it to temporary sentinel value.
*/
#ifndef HAVE_KERNEL_GET_ACL_HANDLE_CACHE
acl = get_cached_acl(ip, type);
if (acl != ACL_NOT_CACHED)
return (acl);
#endif
switch (type) {
case ACL_TYPE_ACCESS:
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
name = XATTR_NAME_POSIX_ACL_ACCESS;
break;
case ACL_TYPE_DEFAULT:
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
name = XATTR_NAME_POSIX_ACL_DEFAULT;
break;
default:
return (ERR_PTR(-EINVAL));
}
size = zpl_xattr_get(ip, name, NULL, 0);
if (size > 0) {
value = kmem_alloc(size, KM_SLEEP);
size = zpl_xattr_get(ip, name, value, size);
}
if (size > 0) {
acl = zpl_acl_from_xattr(value, size);
} else if (size == -ENODATA || size == -ENOSYS) {
acl = NULL;
} else {
acl = ERR_PTR(-EIO);
}
if (size > 0)
kmem_free(value, size);
/* As of Linux 4.7, the kernel get_acl will set this for us */
#ifndef HAVE_KERNEL_GET_ACL_HANDLE_CACHE
if (!IS_ERR(acl))
zpl_set_cached_acl(ip, type, acl);
#endif
return (acl);
}
#if !defined(HAVE_GET_ACL)
static int
__zpl_check_acl(struct inode *ip, int mask)
{
struct posix_acl *acl;
int error;
acl = zpl_get_acl(ip, ACL_TYPE_ACCESS);
if (IS_ERR(acl))
return (PTR_ERR(acl));
if (acl) {
error = posix_acl_permission(ip, acl, mask);
zpl_posix_acl_release(acl);
return (error);
}
return (-EAGAIN);
}
#if defined(HAVE_CHECK_ACL_WITH_FLAGS)
int
zpl_check_acl(struct inode *ip, int mask, unsigned int flags)
{
return (__zpl_check_acl(ip, mask));
}
#elif defined(HAVE_CHECK_ACL)
int
zpl_check_acl(struct inode *ip, int mask)
{
return (__zpl_check_acl(ip, mask));
}
#elif defined(HAVE_PERMISSION_WITH_NAMEIDATA)
int
zpl_permission(struct inode *ip, int mask, struct nameidata *nd)
{
return (generic_permission(ip, mask, __zpl_check_acl));
}
#elif defined(HAVE_PERMISSION)
int
zpl_permission(struct inode *ip, int mask)
{
return (generic_permission(ip, mask, __zpl_check_acl));
}
#endif /* HAVE_CHECK_ACL | HAVE_PERMISSION */
#endif /* !HAVE_GET_ACL */
int
zpl_init_acl(struct inode *ip, struct inode *dir)
{
struct posix_acl *acl = NULL;
int error = 0;
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (0);
if (!S_ISLNK(ip->i_mode)) {
if (ITOZSB(ip)->z_acl_type == ZFS_ACLTYPE_POSIXACL) {
acl = zpl_get_acl(dir, ACL_TYPE_DEFAULT);
if (IS_ERR(acl))
return (PTR_ERR(acl));
}
if (!acl) {
ip->i_mode &= ~current_umask();
ip->i_ctime = current_time(ip);
zfs_mark_inode_dirty(ip);
return (0);
}
}
if ((ITOZSB(ip)->z_acl_type == ZFS_ACLTYPE_POSIXACL) && acl) {
umode_t mode;
if (S_ISDIR(ip->i_mode)) {
error = zpl_set_acl(ip, acl, ACL_TYPE_DEFAULT);
if (error)
goto out;
}
mode = ip->i_mode;
error = __posix_acl_create(&acl, GFP_KERNEL, &mode);
if (error >= 0) {
ip->i_mode = mode;
zfs_mark_inode_dirty(ip);
if (error > 0)
error = zpl_set_acl(ip, acl, ACL_TYPE_ACCESS);
}
}
out:
zpl_posix_acl_release(acl);
return (error);
}
int
zpl_chmod_acl(struct inode *ip)
{
struct posix_acl *acl;
int error;
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (0);
if (S_ISLNK(ip->i_mode))
return (-EOPNOTSUPP);
acl = zpl_get_acl(ip, ACL_TYPE_ACCESS);
if (IS_ERR(acl) || !acl)
return (PTR_ERR(acl));
error = __posix_acl_chmod(&acl, GFP_KERNEL, ip->i_mode);
if (!error)
error = zpl_set_acl(ip, acl, ACL_TYPE_ACCESS);
zpl_posix_acl_release(acl);
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
static int
__zpl_xattr_acl_list_access(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
char *xattr_name = XATTR_NAME_POSIX_ACL_ACCESS;
size_t xattr_size = sizeof (XATTR_NAME_POSIX_ACL_ACCESS);
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (0);
if (list && xattr_size <= list_size)
memcpy(list, xattr_name, xattr_size);
return (xattr_size);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_LIST_WRAPPER(zpl_xattr_acl_list_access);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
static int
__zpl_xattr_acl_list_default(struct inode *ip, char *list, size_t list_size,
const char *name, size_t name_len)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
char *xattr_name = XATTR_NAME_POSIX_ACL_DEFAULT;
size_t xattr_size = sizeof (XATTR_NAME_POSIX_ACL_DEFAULT);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (0);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (list && xattr_size <= list_size)
memcpy(list, xattr_name, xattr_size);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
return (xattr_size);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_LIST_WRAPPER(zpl_xattr_acl_list_default);
static int
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
__zpl_xattr_acl_get_access(struct inode *ip, const char *name,
void *buffer, size_t size)
{
struct posix_acl *acl;
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
int type = ACL_TYPE_ACCESS;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") != 0)
return (-EINVAL);
#endif
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (-EOPNOTSUPP);
acl = zpl_get_acl(ip, type);
if (IS_ERR(acl))
return (PTR_ERR(acl));
if (acl == NULL)
return (-ENODATA);
error = zpl_acl_to_xattr(acl, buffer, size);
zpl_posix_acl_release(acl);
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_GET_WRAPPER(zpl_xattr_acl_get_access);
static int
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
__zpl_xattr_acl_get_default(struct inode *ip, const char *name,
void *buffer, size_t size)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
struct posix_acl *acl;
int type = ACL_TYPE_DEFAULT;
int error;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (strcmp(name, "") != 0)
return (-EINVAL);
#endif
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (-EOPNOTSUPP);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
acl = zpl_get_acl(ip, type);
if (IS_ERR(acl))
return (PTR_ERR(acl));
if (acl == NULL)
return (-ENODATA);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
error = zpl_acl_to_xattr(acl, buffer, size);
zpl_posix_acl_release(acl);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_GET_WRAPPER(zpl_xattr_acl_get_default);
static int
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
__zpl_xattr_acl_set_access(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
struct posix_acl *acl;
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
int type = ACL_TYPE_ACCESS;
int error = 0;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
if (strcmp(name, "") != 0)
return (-EINVAL);
#endif
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (-EOPNOTSUPP);
if (!zpl_inode_owner_or_capable(ip))
return (-EPERM);
if (value) {
acl = zpl_acl_from_xattr(value, size);
if (IS_ERR(acl))
return (PTR_ERR(acl));
else if (acl) {
error = zpl_posix_acl_valid(ip, acl);
if (error) {
zpl_posix_acl_release(acl);
return (error);
}
}
} else {
acl = NULL;
}
error = zpl_set_acl(ip, acl, type);
zpl_posix_acl_release(acl);
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_SET_WRAPPER(zpl_xattr_acl_set_access);
static int
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
__zpl_xattr_acl_set_default(struct inode *ip, const char *name,
const void *value, size_t size, int flags)
{
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
struct posix_acl *acl;
int type = ACL_TYPE_DEFAULT;
int error = 0;
/* xattr_resolve_name will do this for us if this is defined */
#ifndef HAVE_XATTR_HANDLER_NAME
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (strcmp(name, "") != 0)
return (-EINVAL);
#endif
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
return (-EOPNOTSUPP);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (!zpl_inode_owner_or_capable(ip))
return (-EPERM);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (value) {
acl = zpl_acl_from_xattr(value, size);
if (IS_ERR(acl))
return (PTR_ERR(acl));
else if (acl) {
error = zpl_posix_acl_valid(ip, acl);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
if (error) {
zpl_posix_acl_release(acl);
return (error);
}
}
} else {
acl = NULL;
}
error = zpl_set_acl(ip, acl, type);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
zpl_posix_acl_release(acl);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
return (error);
}
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
ZPL_XATTR_SET_WRAPPER(zpl_xattr_acl_set_default);
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* ACL access xattr namespace handlers.
*
* Use .name instead of .prefix when available. xattr_resolve_name will match
* whole name and reject anything that has .name only as prefix.
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
*/
xattr_handler_t zpl_xattr_acl_access_handler =
{
#ifdef HAVE_XATTR_HANDLER_NAME
.name = XATTR_NAME_POSIX_ACL_ACCESS,
#else
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
.prefix = XATTR_NAME_POSIX_ACL_ACCESS,
#endif
.list = zpl_xattr_acl_list_access,
.get = zpl_xattr_acl_get_access,
.set = zpl_xattr_acl_set_access,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
#if defined(HAVE_XATTR_LIST_SIMPLE) || \
defined(HAVE_XATTR_LIST_DENTRY) || \
defined(HAVE_XATTR_LIST_HANDLER)
.flags = ACL_TYPE_ACCESS,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
#endif
};
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
/*
* ACL default xattr namespace handlers.
*
* Use .name instead of .prefix when available. xattr_resolve_name will match
* whole name and reject anything that has .name only as prefix.
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
*/
xattr_handler_t zpl_xattr_acl_default_handler =
{
#ifdef HAVE_XATTR_HANDLER_NAME
.name = XATTR_NAME_POSIX_ACL_DEFAULT,
#else
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
.prefix = XATTR_NAME_POSIX_ACL_DEFAULT,
#endif
.list = zpl_xattr_acl_list_default,
.get = zpl_xattr_acl_get_default,
.set = zpl_xattr_acl_set_default,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
#if defined(HAVE_XATTR_LIST_SIMPLE) || \
defined(HAVE_XATTR_LIST_DENTRY) || \
defined(HAVE_XATTR_LIST_HANDLER)
.flags = ACL_TYPE_DEFAULT,
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
#endif
};
#endif /* CONFIG_FS_POSIX_ACL */
xattr_handler_t *zpl_xattr_handlers[] = {
&zpl_xattr_security_handler,
&zpl_xattr_trusted_handler,
&zpl_xattr_user_handler,
#ifdef CONFIG_FS_POSIX_ACL
&zpl_xattr_acl_access_handler,
&zpl_xattr_acl_default_handler,
#endif /* CONFIG_FS_POSIX_ACL */
NULL
};
Linux 4.5 compat: xattr list handler The registered xattr .list handler was simplified in the 4.5 kernel to only perform a permission check. Given a dentry for the file it must return a boolean indicating if the name is visible. This differs slightly from the previous APIs which also required the function to copy the name in to the provided list and return its size. That is now all the responsibility of the caller. This should be straight forward change to make to ZoL since we've always required the caller to make the copy. However, this was slightly complicated by the need to support 3 older APIs. Yes, between 2.6.32 and 4.5 there are 4 versions of this interface! Therefore, while the functional change in this patch is small it includes significant cleanup to make the code understandable and maintainable. These changes include: - Improved configure checks for .list, .get, and .set interfaces. - Interfaces checked from newest to oldest. - Strict checking for each possible known interface. - Configure fails when no known interface is available. - HAVE_*_XATTR_LIST renamed HAVE_XATTR_LIST_* for consistency with similar iops and fops configure checks. - POSIX_ACL_XATTR_{DEFAULT|ACCESS} were removed forcing callers to move to their replacements, XATTR_NAME_POSIX_ACL_{DEFAULT|ACCESS}. Compatibility wrapper were added for old kernels. - ZPL_XATTR_LIST_WRAPPER added which behaves the same as the existing ZPL_XATTR_{GET|SET} WRAPPERs. Only the inode is guaranteed to be a valid pointer, passing NULL for the 'list' and 'name' variables is allowed and must be checked for. All .list functions were updated to use the wrapper to aid readability. - zpl_xattr_filldir() updated to use the .list function for its permission check which is consistent with the updated Linux 4.5 interface. If a .list function is registered it should return 0 to indicate a name should be skipped, if there is no registered function the name will be added. - Additional documentation from xattr(7) describing the correct behavior for each namespace was added before the relevant handlers. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Issue #4228
2016-01-14 23:01:24 +00:00
static const struct xattr_handler *
zpl_xattr_handler(const char *name)
{
if (strncmp(name, XATTR_USER_PREFIX,
XATTR_USER_PREFIX_LEN) == 0)
return (&zpl_xattr_user_handler);
if (strncmp(name, XATTR_TRUSTED_PREFIX,
XATTR_TRUSTED_PREFIX_LEN) == 0)
return (&zpl_xattr_trusted_handler);
if (strncmp(name, XATTR_SECURITY_PREFIX,
XATTR_SECURITY_PREFIX_LEN) == 0)
return (&zpl_xattr_security_handler);
#ifdef CONFIG_FS_POSIX_ACL
if (strncmp(name, XATTR_NAME_POSIX_ACL_ACCESS,
sizeof (XATTR_NAME_POSIX_ACL_ACCESS)) == 0)
return (&zpl_xattr_acl_access_handler);
if (strncmp(name, XATTR_NAME_POSIX_ACL_DEFAULT,
sizeof (XATTR_NAME_POSIX_ACL_DEFAULT)) == 0)
return (&zpl_xattr_acl_default_handler);
#endif /* CONFIG_FS_POSIX_ACL */
return (NULL);
}
#if !defined(HAVE_POSIX_ACL_RELEASE) || defined(HAVE_POSIX_ACL_RELEASE_GPL_ONLY)
struct acl_rel_struct {
struct acl_rel_struct *next;
struct posix_acl *acl;
clock_t time;
};
#define ACL_REL_GRACE (60*HZ)
#define ACL_REL_WINDOW (1*HZ)
#define ACL_REL_SCHED (ACL_REL_GRACE+ACL_REL_WINDOW)
/*
* Lockless multi-producer single-consumer fifo list.
* Nodes are added to tail and removed from head. Tail pointer is our
* synchronization point. It always points to the next pointer of the last
* node, or head if list is empty.
*/
static struct acl_rel_struct *acl_rel_head = NULL;
static struct acl_rel_struct **acl_rel_tail = &acl_rel_head;
static void
zpl_posix_acl_free(void *arg)
{
struct acl_rel_struct *freelist = NULL;
struct acl_rel_struct *a;
clock_t new_time;
boolean_t refire = B_FALSE;
ASSERT3P(acl_rel_head, !=, NULL);
while (acl_rel_head) {
a = acl_rel_head;
if (ddi_get_lbolt() - a->time >= ACL_REL_GRACE) {
/*
* If a is the last node we need to reset tail, but we
* need to use cmpxchg to make sure it is still the
* last node.
*/
if (acl_rel_tail == &a->next) {
acl_rel_head = NULL;
if (cmpxchg(&acl_rel_tail, &a->next,
&acl_rel_head) == &a->next) {
ASSERT3P(a->next, ==, NULL);
a->next = freelist;
freelist = a;
break;
}
}
/*
* a is not last node, make sure next pointer is set
* by the adder and advance the head.
*/
while (ACCESS_ONCE(a->next) == NULL)
cpu_relax();
acl_rel_head = a->next;
a->next = freelist;
freelist = a;
} else {
/*
* a is still in grace period. We are responsible to
* reschedule the free task, since adder will only do
* so if list is empty.
*/
new_time = a->time + ACL_REL_SCHED;
refire = B_TRUE;
break;
}
}
if (refire)
taskq_dispatch_delay(system_delay_taskq, zpl_posix_acl_free,
NULL, TQ_SLEEP, new_time);
while (freelist) {
a = freelist;
freelist = a->next;
kfree(a->acl);
kmem_free(a, sizeof (struct acl_rel_struct));
}
}
void
zpl_posix_acl_release_impl(struct posix_acl *acl)
{
struct acl_rel_struct *a, **prev;
a = kmem_alloc(sizeof (struct acl_rel_struct), KM_SLEEP);
a->next = NULL;
a->acl = acl;
a->time = ddi_get_lbolt();
/* atomically points tail to us and get the previous tail */
prev = xchg(&acl_rel_tail, &a->next);
ASSERT3P(*prev, ==, NULL);
*prev = a;
/* if it was empty before, schedule the free task */
if (prev == &acl_rel_head)
taskq_dispatch_delay(system_delay_taskq, zpl_posix_acl_free,
NULL, TQ_SLEEP, ddi_get_lbolt() + ACL_REL_SCHED);
}
#endif