ebe7e575ea
Add support for the .zfs control directory. This was accomplished
by leveraging as much of the existing ZFS infrastructure as posible
and updating it for Linux as required. The bulk of the core
functionality is now all there with the following limitations.
*) The .zfs/snapshot directory automount support requires a 2.6.37
or newer kernel. The exception is RHEL6.2 which has backported
the d_automount patches.
*) Creating/destroying/renaming snapshots with mkdir/rmdir/mv
in the .zfs/snapshot directory works as expected. However,
this functionality is only available to root until zfs
delegations are finished.
* mkdir - create a snapshot
* rmdir - destroy a snapshot
* mv - rename a snapshot
The following issues are known defeciences, but we expect them to
be addressed by future commits.
*) Add automount support for kernels older the 2.6.37. This should
be possible using follow_link() which is what Linux did before.
*) Accessing the .zfs/snapshot directory via NFS is not yet possible.
The majority of the ground work for this is complete. However,
finishing this work will require resolving some lingering
integration issues with the Linux NFS kernel server.
*) The .zfs/shares directory exists but no futher smb functionality
has yet been implemented.
Contributions-by: Rohan Puri <rohan.puri15@gmail.com>
Contributiobs-by: Andrew Barnes <barnes333@gmail.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #173
124 lines
2.8 KiB
C
124 lines
2.8 KiB
C
/*
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* CDDL HEADER START
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*
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* The contents of this file are subject to the terms of the
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* Common Development and Distribution License (the "License").
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* You may not use this file except in compliance with the License.
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*
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* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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* or http://www.opensolaris.org/os/licensing.
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* See the License for the specific language governing permissions
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* and limitations under the License.
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*
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* When distributing Covered Code, include this CDDL HEADER in each
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* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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* If applicable, add the following below this CDDL HEADER, with the
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* fields enclosed by brackets "[]" replaced with your own identifying
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* information: Portions Copyright [yyyy] [name of copyright owner]
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*
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* CDDL HEADER END
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*/
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/*
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* Copyright (c) 2011 Gunnar Beutner
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*/
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#include <sys/zfs_vnops.h>
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#include <sys/zfs_znode.h>
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#include <sys/zfs_ctldir.h>
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#include <sys/zpl.h>
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static int
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zpl_encode_fh(struct dentry *dentry, __u32 *fh, int *max_len, int connectable)
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{
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fid_t *fid = (fid_t *)fh;
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struct inode *ip = dentry->d_inode;
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int len_bytes, rc;
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len_bytes = *max_len * sizeof (__u32);
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if (len_bytes < offsetof(fid_t, fid_data))
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return 255;
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fid->fid_len = len_bytes - offsetof(fid_t, fid_data);
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if (zfsctl_is_node(ip))
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rc = zfsctl_fid(ip, fid);
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else
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rc = zfs_fid(ip, fid);
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len_bytes = offsetof(fid_t, fid_data) + fid->fid_len;
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*max_len = roundup(len_bytes, sizeof (__u32)) / sizeof (__u32);
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return (rc == 0 ? FILEID_INO32_GEN : 255);
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}
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static struct dentry *
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zpl_dentry_obtain_alias(struct inode *ip)
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{
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struct dentry *result;
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#ifdef HAVE_D_OBTAIN_ALIAS
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result = d_obtain_alias(ip);
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#else
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result = d_alloc_anon(ip);
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if (result == NULL) {
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iput(ip);
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result = ERR_PTR(-ENOMEM);
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}
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#endif /* HAVE_D_OBTAIN_ALIAS */
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return result;
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}
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static struct dentry *
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zpl_fh_to_dentry(struct super_block *sb, struct fid *fh,
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int fh_len, int fh_type)
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{
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fid_t *fid = (fid_t *)fh;
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struct inode *ip;
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int len_bytes, rc;
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len_bytes = fh_len * sizeof (__u32);
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if (fh_type != FILEID_INO32_GEN ||
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len_bytes < offsetof(fid_t, fid_data) ||
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len_bytes < offsetof(fid_t, fid_data) + fid->fid_len)
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return ERR_PTR(-EINVAL);
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rc = zfs_vget(sb, &ip, fid);
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if (rc != 0)
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return ERR_PTR(-rc);
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ASSERT((ip != NULL) && !IS_ERR(ip));
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return zpl_dentry_obtain_alias(ip);
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}
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static struct dentry *
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zpl_get_parent(struct dentry *child)
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{
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cred_t *cr = CRED();
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struct inode *ip;
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int error;
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crhold(cr);
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error = -zfs_lookup(child->d_inode, "..", &ip, 0, cr, NULL, NULL);
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crfree(cr);
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ASSERT3S(error, <=, 0);
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if (error)
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return ERR_PTR(error);
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return zpl_dentry_obtain_alias(ip);
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}
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const struct export_operations zpl_export_operations = {
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.encode_fh = zpl_encode_fh,
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.fh_to_dentry = zpl_fh_to_dentry,
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.get_parent = zpl_get_parent
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};
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