instead of DOINGSOFTDEP(). The softdep_prealloc() function does nothing
in SU case.
Note that the call should be safe with regard to the vnode relock,
because it is called with MNT_NOWAIT, which does not descend into fsync.
Reviewed by: mckusick
Tested by: pho
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
This count is memoized together with the lookup metadata in directory
inode, and we assert that accesses to lookup metadata are done under
the same lock generation as they were stored. Enabled under DIAGNOSTICS.
UFS saves additional data for parent dirent when doing lookup
(i_offset, i_count, i_endoff), and this data is used later by VOPs
operating on dirents. If parent vnode exclusive lock is dropped and
re-acquired between lookup and the VOP call, we corrupt directories.
Framework asserts that corruption cannot occur that way, by tracking
vnode lock generation counter. Updates to inode dirent members also
save the counter, while users compare current and saved counters
values.
Also, fix a case in ufs_lookup_ino() where i_offset and i_count could
be updated under shared lock. It is not a bug on its own since dvp
i_offset results from such lookup cannot be used, but it causes false
positive in the checker.
In collaboration with: pho
Reviewed by: mckusick (previous version), markj
Tested by: markj (syzkaller), pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D26136
The pointer to vnode is already stored into f_vnode, so f_data can be
reused. Fix all found users of f_data for DTYPE_VNODE.
Provide finit_vnode() helper to initialize file of DTYPE_VNODE type.
Reviewed by: markj (previous version)
Discussed with: freqlabs (openzfs chunk)
Tested by: pho (previous version)
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D26346
requires that new data on growing files be accessible. Thus, the
the fsyncdata() system call must update the on-disk inode when the
size of the file has changed.
This commit adds another inode update flag, IN_SIZEMOD, that gets
set any time that the file size changes. If either the IN_IBLKDATA
or the IN_SIZEMOD flag is set when fdatasync() is called, the
associated inode is synchronously written to disk. We could have
overloaded the IN_IBLKDATA flag to also track size changes since
the only (current) use case for these flags are for fsyncdata(),
but it does seem useful for possible future uses to separately
track the file size changes and the inode block pointer changes.
Reviewed by: kib
MFC with: -r361785
Differential revision: https://reviews.freebsd.org/D25072
the underlying media fails or becomes inaccessible. For example
when a USB flash memory card hosting a UFS filesystem is unplugged.
The strategy for handling disk I/O errors when soft updates are
enabled is to stop writing to the disk of the affected file system
but continue to accept I/O requests and report that all future
writes by the file system to that disk actually succeed. Then
initiate an asynchronous forced unmount of the affected file system.
There are two cases for disk I/O errors:
- ENXIO, which means that this disk is gone and the lower layers
of the storage stack already guarantee that no future I/O to
this disk will succeed.
- EIO (or most other errors), which means that this particular
I/O request has failed but subsequent I/O requests to this
disk might still succeed.
For ENXIO, we can just clear the error and continue, because we
know that the file system cannot affect the on-disk state after we
see this error. For EIO or other errors, we arrange for the geom_vfs
layer to reject all future I/O requests with ENXIO just like is
done when the geom_vfs is orphaned. In both cases, the file system
code can just clear the error and proceed with the forcible unmount.
This new treatment of I/O errors is needed for writes of any buffer
that is involved in a dependency. Most dependencies are described
by a structure attached to the buffer's b_dep field. But some are
created and processed as a result of the completion of the dependencies
attached to the buffer.
Clearing of some dependencies require a read. For example if there
is a dependency that requires an inode to be written, the disk block
containing that inode must be read, the updated inode copied into
place in that buffer, and the buffer then written back to disk.
Often the needed buffer is already in memory and can be used. But
if it needs to be read from the disk, the read will fail, so we
fabricate a buffer full of zeroes and pretend that the read succeeded.
This zero'ed buffer can be updated and written back to disk.
The only case where a buffer full of zeros causes the code to do
the wrong thing is when reading an inode buffer containing an inode
that still has an inode dependency in memory that will reinitialize
the effective link count (i_effnlink) based on the actual link count
(i_nlink) that we read. To handle this case we now store the i_nlink
value that we wrote in the inode dependency so that it can be
restored into the zero'ed buffer thus keeping the tracking of the
inode link count consistent.
Because applications depend on knowing when an attempt to write
their data to stable storage has failed, the fsync(2) and msync(2)
system calls need to return errors if data fails to be written to
stable storage. So these operations return ENXIO for every call
made on files in a file system where we have otherwise been ignoring
I/O errors.
Coauthered by: mckusick
Reviewed by: kib
Tested by: Peter Holm
Approved by: mckusick (mentor)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D24088
These two sysctls were added to support UFS softupdates journalling
with snapshots. However, the changes to fsck to use them were never
committed and there have never been any in-tree uses of these sysctls.
More details from Kirk:
When journalling got added to soft updates, its journal rollback freed
blocks that it thought were no longer in use. But it does not take
snapshots into account (i.e., if a snapshot is still using it, then it
cannot be freed). So I added the needed logic to fsck by having the
free go through the kernel's blkfree code so it could grab blocks that
were still needed by snapshots. That is done using the setbufoutput
hack. I never got that code working reliably, so it is still sitting
in my work directory. Which also explains why you still cannot take
snapshots on filesystems running with journalling...
In looking over my use of this feature, and in particular the troubles
I was having with it, I conclude that it may be better to extract the
code from the kernel that handles freeing blocks claimed by snapshots
and putting it into fsck directly. My original intent was that it is
complex and at the time changing, so only having to maintain it in one
place was appealing. But at this point it has not changed in years and
the hacks like setinode and setbufoutput to be able to use the kernel
code is sufficiently ugly, that I am leaning towards just extracting
it.
Reviewed by: mckusick
MFC after: 1 week
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D24484
This has a side effect of eliminating filedesc slock/sunlock during path
lookup, which in turn removes contention vs concurrent modifications to the fd
table.
Reviewed by: markj, kib
Differential Revision: https://reviews.freebsd.org/D23889
file systems to safely access their disk devices, and adapt FFS to use it.
Also add a new BO_NOBUFS flag to allow enforcing that file systems using
mntfs vnodes do not accidentally use the original devfs vnode to create buffers.
Reviewed by: kib, mckusick
Approved by: imp (mentor)
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D23787
The new structure is copy-on-write. With the assumption that path lookups are
significantly more frequent than chdirs and chrooting this is a win.
This provides stable root and jail root vnodes without the need to reference
them on lookup, which in turn means less work on globally shared structures.
Note this also happens to fix a bug where jail vnode was never referenced,
meaning subsequent access on lookup could run into use-after-free.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D23884
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
This will be used later to add vnodes to the lazy list.
Reviewed by: kib (previous version), jeff
Tested by: pho (in a larger patch)
Differential Revision: https://reviews.freebsd.org/D22994
Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.
Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D21427
the vnode, logical block number, and size of data block that is
being requested. They then use the VOP_BMAP function to calculate
the mapping from logical block number to physical block number from
which to access the data. This change expands the interface to also
pass the physical block number in cases where the VOP_MAP function
may no longer work, for example when a file is being truncated.
No functional change.
Reviewed by: kib
Tested by: Peter Holm
Sponsored by: Netflix
the cg rather than reusuing "ino" for this purpose. This reduces the diff
for an upcoming change that improves handling of I/O errors.
No functional change.
Reviewed by: mckusick
Approved by: mckusick (mentor)
Sponsored by: Netflix
In ffs_valloc(), force reclaim existing vnode on inode reuse, instead
of trying to re-initialize the same vnode for new purposes. This is
done in preparation of changes to the vp->v_object lifecycle handling.
A new FFSV_REPLACE flag to ffs_vgetf() directs the function to
vgone(9) the vnode if found in vfs hash, instead of returning it.
Reviewed by: markj, mckusick
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D21412
filesystems that have block pointers that are out-of-range for their
filesystem. These out-of-range block pointers are corrected by
fsck(8) so are only encountered when an unchecked filesystem is
mounted.
A new "untrusted" flag has been added to the generic mount interface
that can be set when mounting media of unknown provenance or integrity.
For example, a daemon that automounts a filesystem on a flash drive
when it is plugged into a system.
This commit adds a test to UFS/FFS that validates all block numbers
before using them. Because checking for out-of-range blocks adds
unnecessary overhead to normal operation, the tests are only done
when the filesystem is mounted as an "untrusted" filesystem.
Reported by: Christopher Krah, Thomas Barabosch, and Jan-Niclas Hilgert of Fraunhofer FKIE
Reported as: FS-14-UFS-3: Out of bounds read in write-2 (ffs_alloccg)
Reviewed by: kib
Sponsored by: Netflix
filesystem full message is sent to the offending process or the
kernel log if the offending process cannot be identified.
To prevent an explotion of messages, the kernel ppsratecheck()
function is used to limit the messages to one per second. This
revision changes the variable that tracks the rate of these messages
from a systemwide limit to a per-filesystem limit by moving it from
a global variable to a variable in the ufsmount structure.
Suggested by: kib
Reviewed by: kib
Sponsored by: Netflix
rename the source to gsb_crc32.c.
This is a prerequisite of unifying kernel zlib instances.
PR: 229763
Submitted by: Yoshihiro Ota <ota at j.email.ne.jp>
Differential Revision: https://reviews.freebsd.org/D20193
the file associated with the given file descriptor.
Reviewed by: kib, asomers
Reviewed by: cem, jilles, brooks (they reviewed previous version)
Discussed with: pjd, and many others
Differential Revision: https://reviews.freebsd.org/D14567
shorter than its size resulting in a hole as its final block (which
is a violation of the invarients of the UFS filesystem).
Soft updates will always ensure that the file size is correct when
writing inodes to disk for files that contain only direct block
pointers. However soft updates does not roll back sizes for files
with indirect blocks that it has set to unallocated because their
contents have not yet been written to disk. Hence, the file can
appear to have a hole at its end because the block pointer has been
rolled back to zero when its inode was written to disk. Thus,
fsck_ffs calculates the last allocated block in the file. For files
that extend into indirect blocks, fsck_ffs checks for a size past
the last allocated block of the file and if that is found, shortens
the file to reference the last allocated block thus avoiding having
it reference a hole at its end.
Submitted by: Chuck Silvers <chs@netflix.com>
Tested by: Chuck Silvers <chs@netflix.com>
MFC after: 1 week
Sponsored by: Netflix
deletion is active, specifically after a call to ffs_blkrelease_start()
but before the call to ffs_blkrelease_finish(), ffs_blkrelease_start()
will have handed out SINGLETON_KEY rather than starting a collection
sequence. Thus if we get a SINGLETON_KEY passed to ffs_blkrelease_finish(),
we just return rather than trying to finish the nonexistent sequence.
Reported by: Warner Losh (imp@)
Sponsored by: Netflix
Flags prevent open(2) and *at(2) vfs syscalls name lookup from
escaping the starting directory. Supposedly the interface is similar
to the same proposed Linux flags.
Reviewed by: jilles (code, previous version of manpages), 0mp (manpages)
Discussed with: allanjude, emaste, jonathan
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D17547
found that performance was no worse and usually better when running
with TRIM consolidation. Performance improvement was most noticable
when multiple large files are released in a short period of time.
Thus, TRIM consolidation is being enabled by default. Should
operational problems be found, it can be disabled using the command
`sysctl vfs.ffs.dotrimcons=0'. This variable can also be set as a
tunable if early disabling is necessary.
Approved by: re (gjb)
Sponsored by: Netflix
blocks of a file as contiguously as possible. Since the filesystem
does not know how large a file will grow when it is first being
written, it initially places the file in a set of blocks in which
it currently fits. As it grows, it is relocated to areas with
larger contiguous blocks. In this way it saves its large contiguous
sets of blocks for the files that need them and thus avoids
unnecessaily fragmenting its disk space.
We used to skip reallocating the blocks of a file into a contiguous
sequence if the underlying flash device requested BIO_DELETE
notifications, because devices that benefit from BIO_DELETE also
benefit from not moving the data. However, in the algorithm described
above that reallocates the blocks, the destination for the data is
usually moved before the data is written to the initially allocated
location. So we rarely suffer the penalty of extra writes. With
the addition of the consolodation of contiguous blocks into single
BIO_DELETE operations, having fewer but larger contiguous blocks
reduces the number of (slow and expensive) BIO_DELETE operations.
So when doing BIO_DELETE consolodation, we do block reallocation.
Reviewed by: kib
Tested by: Peter Holm
Sponsored by: Netflix
When deleting files on filesystems that are stored on flash-memory
(solid-state) disk drives, the filesystem notifies the underlying
disk of the blocks that it is no longer using. The notification
allows the drive to avoid saving these blocks when it needs to
flash (zero out) one of its flash pages. These notifications of
no-longer-being-used blocks are referred to as TRIM notifications.
In FreeBSD these TRIM notifications are sent from the filesystem
to the drive using the BIO_DELETE command.
Until now, the filesystem would send a separate message to the drive
for each block of the file that was deleted. Each Gigabyte of file
size resulted in over 3000 TRIM messages being sent to the drive.
This burst of messages can overwhelm the drive's task queue causing
multiple second delays for read and write requests.
This implementation collects runs of contiguous blocks in the file
and then consolodates them into a single BIO_DELETE command to the
drive. The BIO_DELETE command describes the run of blocks as a
single large block being deleted. Each Gigabyte of file size can
result in as few as two BIO_DELETE commands and is typically less
than ten. Though these larger BIO_DELETE commands take longer to
run, they do not clog the drive task queue, so read and write
commands can intersperse effectively with them.
Though this new feature has been throughly reviewed and tested, it
is being added disabled by default so as to minimize the possibility
of disrupting the upcoming 12.0 release. It can be enabled by running
``sysctl vfs.ffs.dotrimcons=1''. Users are encouraged to test it.
If no problems arise, we will consider requesting that it be enabled
by default for 12.0.
Reviewed by: kib
Tested by: Peter Holm
Sponsored by: Netflix
driven by problems found with the algorithms being tested for TRIM
consolodation.
Reported by: Peter Holm
Suggested by: kib
Reviewed by: kib
Sponsored by: Netflix
a smaller number of larger TRIM requests. The hope had been to have
the full TRIM consolodation in place for 12.0, but the algorithms
are still under development and need further testing. With this
framework in place it will be possible to easily add TRIM consolodation
once the optimal strategy has been found.
The only functional change with this patch is the elimination of TRIM
requests for blocks that are freed before they have been likely to
have been written.
Reviewed by: kib
Discussed with: Warner Losh and Chuck Silvers
Sponsored by: Netflix
Convert integer structure flags to use um_flags:
int um_candelete; /* devvp supports TRIM */
int um_writesuspended; /* suspension in progress */
become:
#define UM_CANDELETE 0x00000001 /* devvp supports TRIM */
#define UM_WRITESUSPENDED 0x00000002 /* suspension in progress */
This is in preparation for adding other flags to indicate forcible
unmount in progress after a disk failure and possibly forcible
downgrade to read-only.
No functional change intended.
Sponsored by: Netflix
The reference counting that's done in the geom_vfs layer to prevent
delivery of requests to defunct devices only works if all requests go
through that layer. UFS was bypassing that layer for BIO_DELETE requests,
sending them to the geom_consumer directly with g_io_request. Allocate
a buf, fill it in, and call strategy on it instead.
Submitted by: Chuck Silvers
Reviewed by: scottl, imp, kirk
Sponsored by: Netflix
Differential: https://reviews.freebsd.org/D15456
Followup to r313780. Also prefix ext2's and nandfs's versions with
EXT2_ and NANDFS_.
Reported by: kib
Reviewed by: kib, mckusick
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D9623
systems running with a heavy filesystem load. Tracking down this
bug was elusive because there were actually two problems. Sometimes
the in-memory check hash was wrong and sometimes the check hash
computed when doing the read was wrong. The occurrence of either
error caused a check-hash mismatch to be reported.
The first error was that the check hash in the in-memory cylinder
group was incorrect. This error was caused by the following
sequence of events:
- We read a cylinder-group buffer and the check hash is valid.
- We update its cg_time and cg_old_time which makes the in-memory
check-hash value invalid but we do not mark the cylinder group dirty.
- We do not make any other changes to the cylinder group, so we
never mark it dirty, thus do not write it out, and hence never
update the incorrect check hash for the in-memory buffer.
- Later, the buffer gets freed, but the page with the old incorrect
check hash is still in the VM cache.
- Later, we read the cylinder group again, and the first page with
the old check hash is still in the VM cache, but some other pages
are not, so we have to do a read.
- The read does not actually get the first page from disk, but rather
from the VM cache, resulting in the old check hash in the buffer.
- The value computed after doing the read does not match causing the
error to be printed.
The fix for this problem is to only set cg_time and cg_old_time as
the cylinder group is being written to disk. This keeps the in-memory
check-hash valid unless the cylinder group has had other modifications
which will require it to be written with a new check hash calculated.
It also requires that the check hash be recalculated in the in-memory
cylinder group when it is marked clean after doing a background write.
The second problem was that the check hash computed at the end of the
read was incorrect because the calculation of the check hash on
completion of the read was being done too soon.
- When a read completes we had the following sequence:
- bufdone()
-- b_ckhashcalc (calculates check hash)
-- bufdone_finish()
--- vfs_vmio_iodone() (replaces bogus pages with the cached ones)
- When we are reading a buffer where one or more pages are already
in memory (but not all pages, or we wouldn't be doing the read),
the I/O is done with bogus_page mapped in for the pages that exist
in the VM cache. This mapping is done to avoid corrupting the
cached pages if there is any I/O overrun. The vfs_vmio_iodone()
function is responsible for replacing the bogus_page(s) with the
cached ones. But we were calculating the check hash before the
bogus_page(s) were replaced. Hence, when we were calculating the
check hash, we were partly reading from bogus_page, which means
we calculated a bad check hash (e.g., because multiple pages have
been mapped to bogus_page, so its contents are indeterminate).
The second fix is to move the check-hash calculation from bufdone()
to bufdone_finish() after the call to vfs_vmio_iodone() so that it
computes the check hash over the correct set of pages.
With these two changes, the occasional cylinder-group check-hash
errors are gone.
Submitted by: David Pfitzner <dpfitzner@netflix.com>
Reviewed by: kib
Tested by: David Pfitzner
This reduces noise when kernel is compiled by newer GCC versions,
such as one used by external toolchain ports.
Reviewed by: kib, andrew(sys/arm and sys/arm64), emaste(partial), erj(partial)
Reviewed by: jhb (sys/dev/pci/* sys/kern/vfs_aio.c and sys/kern/kern_synch.c)
Differential Revision: https://reviews.freebsd.org/D10385
FFS performs asynchronous inode initialization, using a barrier write
to ensure that the inode block is written before the corresponding
cylinder group header update. Some GEOMs do not appear to handle
BIO_ORDERED correctly, meaning that the barrier write may not work as
intended. The sysctl allows one to work around this problem at the
cost of expensive file creation on new filesystems. The default
behaviour is unchanged.
Reviewed by: kib, mckusick
MFC after: 1 weeks
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D13428
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
