Which will eventually completely replace the agno in it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Convert the raw walks to an iterator, pulling the current AG out of
pag->pag_agno instead of the loop iterator variable.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
They are AG functions, not superblock functions, so move them to the
appropriate location.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
The final parameter of filemap_write_and_wait_range is the end of the
range to flush, not the length of the range to flush.
Fixes: 46afb0628b ("xfs: only flush the unshared range in xfs_reflink_unshare")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Move the XFS_IFEXTENTS check from the callers into xfs_iread_extents to
simplify the code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In preparation of removing the historic icinode struct, move the flags2
field into the containing xfs_inode structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In preparation of removing the historic icinode struct, move the
cowextsize field into the containing xfs_inode structure. Also
switch to use the xfs_extlen_t instead of a uint32_t.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In preparation of removing the historic icinode struct, move the on-disk
size field into the containing xfs_inode structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
If a fs modification (data write, reflink, xattr set, fallocate, etc.)
is unable to reserve enough quota to handle the modification, try
clearing whatever space the filesystem might have been hanging onto in
the hopes of speeding up the filesystem. The flushing behavior will
become particularly important when we add deferred inode inactivation
because that will increase the amount of space that isn't actively tied
to user data.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that we've converted xfs_reflink_remap_extent to use the new
xfs_trans_alloc_inode API, we can focus on its slightly unusual behavior
with regard to quota reservations.
Since it's valid to remap written blocks into a hole, we must be able to
increase the quota count by the number of blocks in the mapping.
However, the incore space reservation process requires us to supply an
asymptotic guess before we can gain exclusive access to resources. We'd
like to reserve all the quota we need up front, but we also don't want
to fail a written -> allocated remap operation unnecessarily.
The solution is to make the remap_extents function call the transaction
allocation function twice. The first time we ask to reserve enough
space and quota to handle the absolute worst case situation, but if that
fails, we can fall back to the old strategy: ask for the bare minimum
space reservation upfront and increase the quota reservation later if we
need to.
Later in this patchset we change the transaction and quota code to try
to reclaim space if we cannot reserve free space or quota.
Restructuring the remap_extent function in this manner means that if the
fallback increase fails, we can pass that back to the caller knowing
that the transaction allocation already tried freeing space.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The two remaining callers of xfs_trans_reserve_quota_nblks are in the
reflink code. These conversions aren't as uniform as the previous
conversions, so call that out in a separate patch.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Modify xfs_trans_reserve_quota_nblks so that we can reserve data and
realtime blocks from the dquot at the same time. This change has the
theoretical side effect that for allocations to realtime files we will
reserve from the dquot both the number of rtblocks being allocated and
the number of bmbt blocks that might be needed to add the mapping.
However, since the mount code disables quota if it finds a realtime
device, this should not result in any behavior changes.
Now that we've moved the inode creation callers away from using the
_nblks function, we can repurpose the (now unused) ninos argument for
realtime blocks, so make that change. This also replaces the flags
argument with a boolean parameter to force the reservation since we
don't need to distinguish between data and rt quota reservations any
more, and the only flag being passed in was FORCE_RES.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
xfs_trans_cancel will release all the quota resources that were reserved
on behalf of the transaction, so get rid of the explicit unreserve step.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a couple of convenience wrappers for creating and deleting quota
block reservations against future changes.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Convert a few xfs_trans_*reserve* callsites that are open-coding other
convenience functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Remapping an extent involves unmapping the existing extent and mapping
in the new extent. When unmapping, an extent containing the entire unmap
range can be split into two extents,
i.e. | Old extent | hole | Old extent |
Hence extent count increases by 1.
Mapping in the new extent into the destination file can increase the
extent count by 1.
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Moving an extent to data fork can cause a sub-interval of an existing
extent to be unmapped. This will increase extent count by 1. Mapping in
the new extent can increase the extent count by 1 again i.e.
| Old extent | New extent | Old extent |
Hence number of extents increases by 2.
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Chandan Babu R <chandanrlinux@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There's no reason to flush an entire file when we're unsharing part of
a file. Therefore, only initiate writeback on the selected range.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Delete repeated words in fs/xfs/.
{we, that, the, a, to, fork}
Change "it it" to "it is" in one location.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
To: linux-fsdevel@vger.kernel.org
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: linux-xfs@vger.kernel.org
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Move the double-inode locking helpers to xfs_inode.c since they're not
specific to reflink.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Refactor the two functions that we use to lock and unlock two inodes to
block userspace from initiating IO against a file, whether via system
calls or mmap activity.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Fix the return value of xfs_reflink_remap_prep so that its return value
conventions match the rest of xfs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
If the source and destination map are identical, we can skip the remap
step to save some time.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
When logging quota block count updates during a reflink operation, we
only log the /delta/ of the block count changes to the dquot. Since we
now know ahead of time the extent type of both dmap and smap (and that
they have the same length), we know that we only need to reserve quota
blocks for dmap's blockcount if we're mapping it into a hole.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Now that we've reworked xfs_reflink_remap_extent to remap only one
extent per transaction, we actually know if the extent being removed is
an allocated mapping. This means that we now know ahead of time if
we're going to be touching the data fork.
Since we only need blocks for a bmbt split if we're going to update the
data fork, we only need to get quota reservation if we know we're going
to touch the data fork.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The existing reflink remapping loop has some structural problems that
need addressing:
The biggest problem is that we create one transaction for each extent in
the source file without accounting for the number of mappings there are
for the same range in the destination file. In other words, we don't
know the number of remap operations that will be necessary and we
therefore cannot guess the block reservation required. On highly
fragmented filesystems (e.g. ones with active dedupe) we guess wrong,
run out of block reservation, and fail.
The second problem is that we don't actually use the bmap intents to
their full potential -- instead of calling bunmapi directly and having
to deal with its backwards operation, we could call the deferred ops
xfs_bmap_unmap_extent and xfs_refcount_decrease_extent instead. This
makes the frontend loop much simpler.
Solve all of these problems by refactoring the remapping loops so that
we only perform one remapping operation per transaction, and each
operation only tries to remap a single extent from source to dest.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reported-by: Edwin Török <edwin@etorok.net>
Tested-by: Edwin Török <edwin@etorok.net>
The name of this predicate is a little misleading -- it decides if the
extent mapping is allocated and written. Change the name to be more
direct, as we're going to add a new predicate in the next patch.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Quota reservations are supposed to account for the blocks that might be
allocated due to a bmap btree split. Reflink doesn't do this, so fix
this to make the quota accounting more accurate before we start
rearranging things.
Fixes: 862bb360ef ("xfs: reflink extents from one file to another")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
In the reflink extent remap function, it turns out that uirec (the block
mapping corresponding only to the part of the passed-in mapping that got
unmapped) was not fully initialized. Specifically, br_state was not
being copied from the passed-in struct to the uirec. This could lead to
unpredictable results such as the reflinked mapping being marked
unwritten in the destination file.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Drop the null buffer pointer checks in all code that calls
xfs_alloc_read_agf and doesn't pass XFS_ALLOC_FLAG_TRYLOCK because
they're no longer necessary.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Fixes coccicheck warning:
fs/xfs/xfs_reflink.c:236:9-10: WARNING: return of 0/1 in function 'xfs_inode_need_cow' with return type bool
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
[darrick: rename the function so it doesn't sound like a predicate]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Introduce a new #define for the maximum supported file block offset.
We'll use this in the next patch to make it more obvious that we're
doing some operation for all possible inode fork mappings after a given
offset. We can't use ULLONG_MAX here because bunmapi uses that to
detect when it's done.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xfs_bmapi_write() takes a total block requirement parameter that is
passed down to the block allocation code and is used to specify the
total block requirement of the associated transaction. This is used
to try and select an AG that can not only satisfy the requested
extent allocation, but can also accommodate subsequent allocations
that might be required to complete the transaction. For example,
additional bmbt block allocations may be required on insertion of
the resulting extent to an inode data fork.
While it's important for callers to calculate and reserve such extra
blocks in the transaction, it is not necessary to pass the total
value to xfs_bmapi_write() in all cases. The latter automatically
sets minleft to ensure that sufficient free blocks remain after the
allocation attempt to expand the format of the associated inode
(i.e., such as extent to btree conversion, btree splits, etc).
Therefore, any callers that pass a total block requirement of the
bmap mapping length plus worst case bmbt expansion essentially
specify the additional reservation requirement twice. These callers
can pass a total of zero to rely on the bmapi minleft policy.
Beyond being superfluous, the primary motivation for this change is
that the total reservation logic in the bmbt code is dubious in
scenarios where minlen < maxlen and a maxlen extent cannot be
allocated (which is more common for data extent allocations where
contiguity is not required). The total value is based on maxlen in
the xfs_bmapi_write() caller. If the bmbt code falls back to an
allocation between minlen and maxlen, that allocation will not
succeed until total is reset to minlen, which essentially throws
away any additional reservation included in total by the caller. In
addition, the total value is not reset until after alignment is
dropped, which means that such callers drop alignment far too
aggressively than necessary.
Update all callers of xfs_bmapi_write() that pass a total block
value of the mapping length plus bmbt reservation to instead pass
zero and rely on xfs_bmapi_minleft() to enforce the bmbt reservation
requirement. This trades off slightly less conservative AG selection
for the ability to preserve alignment in more scenarios.
xfs_bmapi_write() callers that incorporate unrelated or additional
reservations in total beyond what is already included in minleft
must continue to use the former.
Signed-off-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>
Instead of lots of magic conditionals in the main write_begin
handler this make the intent very clear. Thing will become even
better once we support delayed allocations for extent size hints
and realtime allocations.
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>
xfs_reflink_allocate_cow consumes the source data fork imap, and
potentially returns the COW fork imap. Split the arguments in two
to clear up the calling conventions and to prepare for returning
a source iomap from ->iomap_begin.
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 xfs_file_unshare is not completely dumb we can just call it
directly without iterating the extent and reflink btrees ourselves.
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>
xfs_file_dirty is used to unshare reflink blocks. Rename the function
to xfs_file_unshare to better document that purpose, and skip iomaps
that are not shared and don't need zeroing. This will allow to simplify
the caller.
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>
Remove the return value from the functions that schedule deferred bmap
operations since they never fail and do not return status.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Remove the return value from the functions that schedule deferred
refcount operations since they never fail and do not return status.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
While trawling through the dedupe file comparison code trying to fix
page deadlocking problems, Dave Chinner noticed that the reflink code
only takes shared IOLOCK/MMAPLOCKs on the source file. Because
page_mkwrite and directio writes do not take the EXCL versions of those
locks, this means that reflink can race with writer processes.
For pure remapping this can lead to undefined behavior and file
corruption; for dedupe this means that we cannot be sure that the
contents are identical when we decide to go ahead with the remapping.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Instead of a magic flag for xfs_trans_alloc, just ensure all callers
that can't relclaim through the file system use memalloc_nofs_save to
set the per-task nofs flag.
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>
There are many, many xfs header files which are included but
unneeded (or included twice) in the xfs code, so remove them.
nb: xfs_linux.h includes about 9 headers for everyone, so those
explicit includes get removed by this. I'm not sure what the
preference is, but if we wanted explicit includes everywhere,
a followup patch could remove those xfs_*.h includes from
xfs_linux.h and move them into the files that need them.
Or it could be left as-is.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
smatch complained about some uninitialized error returns, so fix those.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.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>
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>
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>
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>
The io_type field contains what is basically a summary of information
from the inode fork and the imap. But we can just as easily use that
information directly, simplifying a few bits here and there and
improving the trace points.
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>