Pull xfs cleanups from Darrick Wong:
"Here's a few more cleanups that trickled in for the merge window.
It's all fixes for static checker complaints and slowly unwinding
typedef usage. The four patches here have gone through a few days
worth of fstest runs with no new problems observed.
Summary:
- Fix some clang/smatch/sparse warnings about uninitialized
variables.
- Clean up some typedef usage"
* tag 'xfs-5.1-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: clean up xfs_dir2_leaf_addname
xfs: zero initialize highstale and lowstale in xfs_dir2_leaf_addname
xfs: clean up xfs_dir2_leafn_add
xfs: Zero initialize highstale and lowstale in xfs_dir2_leafn_add
Smatch complains about the following:
fs/xfs/libxfs/xfs_dir2_leaf.c:848 xfs_dir2_leaf_addname() error:
uninitialized symbol 'lowstale'.
fs/xfs/libxfs/xfs_dir2_leaf.c:849 xfs_dir2_leaf_addname() error:
uninitialized symbol 'highstale'.
I don't think there's any incorrect behavior associated with the
uninitialized variable, but as the author of the previous zero-init
patch points out, it's best not to be passing around pointers to
uninitialized stack areas.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
When building with -Wsometimes-uninitialized, Clang warns:
fs/xfs/libxfs/xfs_dir2_node.c:481:6: warning: variable 'lowstale' is
used uninitialized whenever 'if' condition is false
[-Wsometimes-uninitialized]
fs/xfs/libxfs/xfs_dir2_node.c:481:6: warning: variable 'highstale' is
used uninitialized whenever 'if' condition is false
[-Wsometimes-uninitialized]
While it isn't technically wrong, it isn't a problem in practice because
highstale and lowstale are only initialized in xfs_dir2_leafn_add when
compact is not zero then they are passed to xfs_dir3_leaf_find_entry,
where they are initialized before use when compact is zero. Regardless,
it's better not to be passing around uninitialized stack memory so zero
initialize these variables, which silences this warning.
Link: https://github.com/ClangBuiltLinux/linux/issues/393
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Pull block layer updates from Jens Axboe:
"Not a huge amount of changes in this round, the biggest one is that we
finally have Mings multi-page bvec support merged. Apart from that,
this pull request contains:
- Small series that avoids quiescing the queue for sysfs changes that
match what we currently have (Aleksei)
- Series of bcache fixes (via Coly)
- Series of lightnvm fixes (via Mathias)
- NVMe pull request from Christoph. Nothing major, just SPDX/license
cleanups, RR mp policy (Hannes), and little fixes (Bart,
Chaitanya).
- BFQ series (Paolo)
- Save blk-mq cpu -> hw queue mapping, removing a pointer indirection
for the fast path (Jianchao)
- fops->iopoll() added for async IO polling, this is a feature that
the upcoming io_uring interface will use (Christoph, me)
- Partition scan loop fixes (Dongli)
- mtip32xx conversion from managed resource API (Christoph)
- cdrom registration race fix (Guenter)
- MD pull from Song, two minor fixes.
- Various documentation fixes (Marcos)
- Multi-page bvec feature. This brings a lot of nice improvements
with it, like more efficient splitting, larger IOs can be supported
without growing the bvec table size, and so on. (Ming)
- Various little fixes to core and drivers"
* tag 'for-5.1/block-20190302' of git://git.kernel.dk/linux-block: (117 commits)
block: fix updating bio's front segment size
block: Replace function name in string with __func__
nbd: propagate genlmsg_reply return code
floppy: remove set but not used variable 'q'
null_blk: fix checking for REQ_FUA
block: fix NULL pointer dereference in register_disk
fs: fix guard_bio_eod to check for real EOD errors
blk-mq: use HCTX_TYPE_DEFAULT but not 0 to index blk_mq_tag_set->map
block: optimize bvec iteration in bvec_iter_advance
block: introduce mp_bvec_for_each_page() for iterating over page
block: optimize blk_bio_segment_split for single-page bvec
block: optimize __blk_segment_map_sg() for single-page bvec
block: introduce bvec_nth_page()
iomap: wire up the iopoll method
block: add bio_set_polled() helper
block: wire up block device iopoll method
fs: add an iopoll method to struct file_operations
loop: set GENHD_FL_NO_PART_SCAN after blkdev_reread_part()
loop: do not print warn message if partition scan is successful
block: bounce: make sure that bvec table is updated
...
statx(2) notes that any attribute that is not indicated as supported by
stx_attributes_mask has no usable value. Commit 5f955f26f3 ("xfs: report
crtime and attribute flags to statx") added support for informing userspace
of extra file attributes but forgot to list these flags as supported
making reporting them rather useless for the pedantic userspace author.
$ git describe --contains 5f955f26f3
v4.11-rc6~5^2^2~2
Fixes: 5f955f26f3 ("xfs: report crtime and attribute flags to statx")
Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: add a comment reminding people to keep attributes_mask up to date]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Rework the data flow in xfs_file_iomap_begin where we decide if we have
to break shared extents.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Don't pass raw iomap flags to xfs_reflink_allocate_cow; signal our
intention with a boolean argument.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Store the request queue the last bio was submitted to in the iocb
private data in addition to the cookie so that we find the right block
device. Also refactor the common direct I/O bio submission code into a
nice little helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Modified to use bio_set_polled().
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A previous commit removed the initialization of variable 'error' to zero,
and can cause a bogus error return. This occurs when error contains a
non-zero garbage value and the call to xchk_should_terminate detects a
pending fatal signal and checks for a zero error before setting it
to -EAGAIN. Fix the issue by initializing error to zero.
Fixes: b9454fe056 ("xfs: clean up the inode cluster checking in the inobt scrub")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Add a mode where XFS never overwrites existing blocks in place. This
is to aid debugging our COW code, and also put infatructure in place
for things like possible future support for zoned block devices, which
can't support overwrites.
This mode is enabled globally by doing a:
echo 1 > /sys/fs/xfs/debug/always_cow
Note that the parameter is global to allow running all tests in xfstests
easily in this mode, which would not easily be possible with a per-fs
sysfs file.
In always_cow mode persistent preallocations are disabled, and fallocate
will fail when called with a 0 mode (with our without
FALLOC_FL_KEEP_SIZE), and not create unwritten extent for zeroed space
when called with FALLOC_FL_ZERO_RANGE or FALLOC_FL_UNSHARE_RANGE.
There are a few interesting xfstests failures when run in always_cow
mode:
- generic/392 fails because the bytes used in the file used to test
hole punch recovery are less after the log replay. This is
because the blocks written and then punched out are only freed
with a delay due to the logging mechanism.
- xfs/170 will fail as the already fragile file streams mechanism
doesn't seem to interact well with the COW allocator
- xfs/180 xfs/182 xfs/192 xfs/198 xfs/204 and xfs/208 will claim
the file system is badly fragmented, but there is not much we
can do to avoid that when always writing out of place
- xfs/205 fails because overwriting a file in always_cow mode
will require new space allocation and the assumption in the
test thus don't work anymore.
- xfs/326 fails to modify the file at all in always_cow mode after
injecting the refcount error, leading to an unexpected md5sum
after the remount, but that again is expected
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
No user of it in the iomap code at the moment, but we should not
actively report wrong information if we can trivially get it right.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If we have racing buffered and direct I/O COW fork extents under
writeback can have been moved to the data fork by the time we call
xfs_reflink_convert_cow from xfs_submit_ioend. This would be mostly
harmless as the block numbers don't change by this move, except for
the fact that xfs_bmapi_write will crash or trigger asserts when
not finding existing extents, even despite trying to paper over this
with the XFS_BMAPI_CONVERT_ONLY flag.
Instead of special casing non-transaction conversions in the already
way too complicated xfs_bmapi_write just add a new helper for the much
simpler non-transactional COW fork case, which simplify ignores not
found extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Besides simplifying the code a bit this allows to actually implement
the behavior of using COW preallocation for non-COW data mentioned
in the current comments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This only matters if we want to write data through the COW fork that is
not actually an overwrite of existing data. Reasons for that are
speculative COW fork allocations using the cowextsize, or a mode where
we always write through the COW fork. Currently both can't actually
happen, but I plan to enable them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
While using delalloc for extsize hints is generally a good idea, the
current code that does so only for COW doesn't help us much and creates
a lot of special cases. Switch it to use real allocations like we
do for direct I/O.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
We speculatively allocate extents in the COW fork to reduce
fragmentation. But when we write data into such COW fork blocks that
do now shadow an allocation in the data fork SEEK_DATA will not
correctly report it, as it only looks at the data fork extents.
The only reason why that hasn't been an issue so far is because
we even use these speculative COW fork preallocations over holes in
the data fork at all for buffered writes, and blocks in the COW
fork that are written by direct writes are moved into the data
fork immediately at I/O completion time.
Add a new set of iomap_ops for SEEK_HOLE/SEEK_DATA which looks into
both the COW and data fork, and reports all COW extents as unwritten
to the iomap layer. While this isn't strictly true for COW fork
extents that were already converted to real extents, the practical
semantics that you can't read data from them until they are moved
into the data fork are very similar, and this will force the iomap
layer into probing the extents for actually present data.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Move checking for invalid zero blocks and setting of various iomap flags
into this helper. Also make it deal with "raw" delalloc extents to
avoid clutter in the callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Create a separate magic16 check function so that we don't run afoul of
static checkers.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
While we can only truncate a block under the page lock for the current
page, there is no high-level synchronization for moving extents from the
COW to the data fork. This means that for example we can have another
thread doing a direct I/O completion that moves extents from the COW to
the data fork race with writeback. While this race is very hard to hit
the always_cow seems to reproduce it reasonably well, and it also exists
without that. Because of that there is a chance that a delalloc
conversion for the COW fork might not find any extents to convert. In
that case we should retry the whole block lookup and now find the blocks
in the data fork.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Now that we properly handle the race with truncate in the delalloc
allocator there is no need to short cut this exceptional case earlier
on.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This function is a small wrapper only used by the writeback code, so
move it together with the writeback code and simplify it down to the
glorified do { } while loop that is now is.
A few bits intentionally got lost here: no need to call xfs_qm_dqattach
because quotas are always attached when we create the delalloc
reservation, and no need for the imap->br_startblock == 0 check given
that xfs_bmapi_convert_delalloc already has a WARN_ON_ONCE for exactly
that condition.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
