Commit Graph

361 Commits

Author SHA1 Message Date
Linus Torvalds
17fa6a5f93 vfs-6.12-rc6.iomap
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Merge tag 'vfs-6.12-rc6.iomap' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs

Pull iomap fixes from Christian Brauner:
 "Fixes for iomap to prevent data corruption bugs in the fallocate
  unshare range implementation of fsdax and a small cleanup to turn
  iomap_want_unshare_iter() into an inline function"

* tag 'vfs-6.12-rc6.iomap' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  iomap: turn iomap_want_unshare_iter into an inline function
  fsdax: dax_unshare_iter needs to copy entire blocks
  fsdax: remove zeroing code from dax_unshare_iter
  iomap: share iomap_unshare_iter predicate code with fsdax
  xfs: don't allocate COW extents when unsharing a hole
2024-11-01 07:45:00 -10:00
Christoph Hellwig
6db388585e
iomap: turn iomap_want_unshare_iter into an inline function
iomap_want_unshare_iter currently sits in fs/iomap/buffered-io.c, which
depends on CONFIG_BLOCK.  It is also in used in fs/dax.c whіch has no
such dependency.  Given that it is a trivial check turn it into an inline
in include/linux/iomap.h to fix the DAX && !BLOCK build.

Fixes: 6ef6a0e821 ("iomap: share iomap_unshare_iter predicate code with fsdax")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20241015041350.118403-1-hch@lst.de
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-21 17:01:01 +02:00
Christoph Hellwig
b784951662 iomap: move locking out of iomap_write_delalloc_release
XFS (which currently is the only user of iomap_write_delalloc_release)
already holds invalidate_lock for most zeroing operations.  To be able
to avoid a deadlock it needs to stop taking the lock, but doing so
in iomap would leak XFS locking details into iomap.

To avoid this require the caller to hold invalidate_lock when calling
iomap_write_delalloc_release instead of taking it there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2024-10-15 11:37:42 +02:00
Christoph Hellwig
caf0ea451d iomap: remove iomap_file_buffered_write_punch_delalloc
Currently iomap_file_buffered_write_punch_delalloc can be called from
XFS either with the invalidate lock held or not.  To fix this while
keeping the locking in the file system and not the iomap library
code we'll need to life the locking up into the file system.

To prepare for that, open code iomap_file_buffered_write_punch_delalloc
in the only caller, and instead export iomap_write_delalloc_release.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2024-10-15 11:37:42 +02:00
Christoph Hellwig
c0adf8c3a9 iomap: factor out a iomap_last_written_block helper
Split out a pice of logic from iomap_file_buffered_write_punch_delalloc
that is useful for all iomap_end implementations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
2024-10-15 11:37:41 +02:00
Darrick J. Wong
6ef6a0e821
iomap: share iomap_unshare_iter predicate code with fsdax
The predicate code that iomap_unshare_iter uses to decide if it's really
needs to unshare a file range mapping should be shared with the fsdax
version, because right now they're opencoded and inconsistent.

Note that we simplify the predicate logic a bit -- we no longer allow
unsharing of inline data mappings, but there aren't any filesystems that
allow shared inline data currently.

This is a fix in the sense that it should have been ported to fsdax.

Fixes: b53fdb215d ("iomap: improve shared block detection in iomap_unshare_iter")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/172796813294.1131942.15762084021076932620.stgit@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-07 13:51:47 +02:00
Darrick J. Wong
a311a08a42
iomap: constrain the file range passed to iomap_file_unshare
File contents can only be shared (i.e. reflinked) below EOF, so it makes
no sense to try to unshare ranges beyond EOF.  Constrain the file range
parameters here so that we don't have to do that in the callers.

Fixes: 5f4e5752a8 ("fs: add iomap_file_dirty")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20241002150213.GC21853@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-03 10:22:28 +02:00
Darrick J. Wong
f7a4874d97
iomap: don't bother unsharing delalloc extents
If unshare encounters a delalloc reservation in the srcmap, that means
that the file range isn't shared because delalloc reservations cannot be
reflinked.  Therefore, don't try to unshare them.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20241002150040.GB21853@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-10-03 10:22:25 +02:00
Linus Torvalds
171754c380 vfs-6.12.blocksize
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Merge tag 'vfs-6.12.blocksize' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs

Pull vfs blocksize updates from Christian Brauner:
 "This contains the vfs infrastructure as well as the xfs bits to enable
  support for block sizes (bs) larger than page sizes (ps) plus a few
  fixes to related infrastructure.

  There has been efforts over the last 16 years to enable enable Large
  Block Sizes (LBS), that is block sizes in filesystems where bs > page
  size. Through these efforts we have learned that one of the main
  blockers to supporting bs > ps in filesystems has been a way to
  allocate pages that are at least the filesystem block size on the page
  cache where bs > ps.

  Thanks to various previous efforts it is possible to support bs > ps
  in XFS with only a few changes in XFS itself. Most changes are to the
  page cache to support minimum order folio support for the target block
  size on the filesystem.

  A motivation for Large Block Sizes today is to support high-capacity
  (large amount of Terabytes) QLC SSDs where the internal Indirection
  Unit (IU) are typically greater than 4k to help reduce DRAM and so in
  turn cost and space. In practice this then allows different
  architectures to use a base page size of 4k while still enabling
  support for block sizes aligned to the larger IUs by relying on high
  order folios on the page cache when needed.

  It also allows to take advantage of the drive's support for atomics
  larger than 4k with buffered IO support in Linux. As described this
  year at LSFMM, supporting large atomics greater than 4k enables
  databases to remove the need to rely on their own journaling, so they
  can disable double buffered writes, which is a feature different cloud
  providers are already enabling through custom storage solutions"

* tag 'vfs-6.12.blocksize' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (22 commits)
  Documentation: iomap: fix a typo
  iomap: remove the iomap_file_buffered_write_punch_delalloc return value
  iomap: pass the iomap to the punch callback
  iomap: pass flags to iomap_file_buffered_write_punch_delalloc
  iomap: improve shared block detection in iomap_unshare_iter
  iomap: handle a post-direct I/O invalidate race in iomap_write_delalloc_release
  docs:filesystems: fix spelling and grammar mistakes in iomap design page
  filemap: fix htmldoc warning for mapping_align_index()
  iomap: make zero range flush conditional on unwritten mappings
  iomap: fix handling of dirty folios over unwritten extents
  iomap: add a private argument for iomap_file_buffered_write
  iomap: remove set_memor_ro() on zero page
  xfs: enable block size larger than page size support
  xfs: make the calculation generic in xfs_sb_validate_fsb_count()
  xfs: expose block size in stat
  xfs: use kvmalloc for xattr buffers
  iomap: fix iomap_dio_zero() for fs bs > system page size
  filemap: cap PTE range to be created to allowed zero fill in folio_map_range()
  mm: split a folio in minimum folio order chunks
  readahead: allocate folios with mapping_min_order in readahead
  ...
2024-09-20 17:53:17 -07:00
Christoph Hellwig
4bceb9ba05
iomap: remove the iomap_file_buffered_write_punch_delalloc return value
iomap_file_buffered_write_punch_delalloc can only return errors if either
the ->punch callback returned an error, or if someone changed the API of
mapping_seek_hole_data to return a negative error code that is not
-ENXIO.

As the only instance of ->punch never returns an error, an such an error
would be fatal anyway remove the entire error propagation and don't
return an error code from iomap_file_buffered_write_punch_delalloc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240910043949.3481298-6-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-10 11:14:15 +02:00
Christoph Hellwig
492f53758f
iomap: pass the iomap to the punch callback
XFS will need to look at the flags in the iomap structure, so pass it
down all the way to the callback.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240910043949.3481298-5-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-10 11:14:15 +02:00
Christoph Hellwig
11596dc3df
iomap: pass flags to iomap_file_buffered_write_punch_delalloc
To fix short write error handling, We'll need to figure out what operation
iomap_file_buffered_write_punch_delalloc is called for.  Pass the flags
argument on to it, and reorder the argument list to match that of
->iomap_end so that the compiler only has to add the new punch argument
to the end of it instead of reshuffling the registers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240910043949.3481298-4-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-10 11:14:14 +02:00
Christoph Hellwig
b53fdb215d
iomap: improve shared block detection in iomap_unshare_iter
Currently iomap_unshare_iter relies on the IOMAP_F_SHARED flag to detect
blocks to unshare.  This is reasonable, but IOMAP_F_SHARED is also useful
for the file system to do internal book keeping for out of place writes.
XFS used to that, until it got removed in commit 72a048c105
("xfs: only set IOMAP_F_SHARED when providing a srcmap to a write")
because unshare for incorrectly unshare such blocks.

Add an extra safeguard by checking the explicitly provided srcmap instead
of the fallback to the iomap for valid data, as that catches the case
where we'd just copy from the same place we'd write to easily, allowing
to reinstate setting IOMAP_F_SHARED for all XFS writes that go to the
COW fork.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240910043949.3481298-3-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-10 11:13:43 +02:00
Christoph Hellwig
7a9d43eace
iomap: handle a post-direct I/O invalidate race in iomap_write_delalloc_release
When direct I/O completions invalidates the page cache it holds neither the
i_rwsem nor the invalidate_lock so it can be racing with
iomap_write_delalloc_release.  If the search for the end of the region that
contains data returns the start offset we hit such a race and just need to
look for the end of the newly created hole instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240910043949.3481298-2-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-10 11:13:43 +02:00
Brian Foster
7d9b474ee4 iomap: make zero range flush conditional on unwritten mappings
iomap_zero_range() flushes pagecache to mitigate consistency
problems with dirty pagecache and unwritten mappings. The flush is
unconditional over the entire range because checking pagecache state
after mapping lookup is racy with writeback and reclaim. There are
ways around this using iomap's mapping revalidation mechanism, but
this is not supported by all iomap based filesystems and so is not a
generic solution.

There is another way around this limitation that is good enough to
filter the flush for most cases in practice. If we check for dirty
pagecache over the target range (instead of unconditionally flush),
we can keep track of whether the range was dirty before lookup and
defer the flush until/unless we see a combination of dirty cache
backed by an unwritten mapping. We don't necessarily know whether
the dirty cache was backed by the unwritten maping or some other
(written) part of the range, but the impliciation of a false
positive here is a spurious flush and thus relatively harmless.

Note that we also flush for hole mappings because iomap_zero_range()
is used for partial folio zeroing in some cases. For example, if a
folio straddles EOF on a sub-page FSB size fs, the post-eof portion
is hole-backed and dirtied/written via mapped write, and then i_size
increases before writeback can occur (which otherwise zeroes the
post-eof portion of the EOF folio), then the folio becomes
inconsistent with disk until reclaimed. A flush in this case
executes partial zeroing from writeback, and iomap knows that there
is otherwise no I/O to submit for hole backed mappings.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Link: https://lore.kernel.org/r/20240830145634.138439-3-bfoster@redhat.com
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-03 15:01:24 +02:00
Brian Foster
c5c810b94c iomap: fix handling of dirty folios over unwritten extents
The iomap zero range implementation doesn't properly handle dirty
pagecache over unwritten mappings. It skips such mappings as if they
were pre-zeroed. If some part of an unwritten mapping is dirty in
pagecache from a previous write, the data in cache should be zeroed
as well. Instead, the data is left in cache and creates a stale data
exposure problem if writeback occurs sometime after the zero range.

Most callers are unaffected by this because the higher level
filesystem contexts that call zero range typically perform a filemap
flush of the target range for other reasons. A couple contexts that
don't otherwise need to flush are write file size extension and
truncate in XFS. The former path is currently susceptible to the
stale data exposure problem and the latter performs a flush
specifically to work around it.

This is clearly inconsistent and incomplete. As a first step toward
correcting behavior, lift the XFS workaround to iomap_zero_range()
and unconditionally flush the range before the zero range operation
proceeds. While this appears to be a bit of a big hammer, most all
users already do this from calling context save for the couple of
exceptions noted above. Future patches will optimize or elide this
flush while maintaining functional correctness.

Fixes: ae259a9c85 ("fs: introduce iomap infrastructure")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Link: https://lore.kernel.org/r/20240830145634.138439-2-bfoster@redhat.com
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-03 15:01:24 +02:00
Josef Bacik
31754ea6cb iomap: add a private argument for iomap_file_buffered_write
In order to switch fuse over to using iomap for buffered writes we need
to be able to have the struct file for the original write, in case we
have to read in the page to make it uptodate.  Handle this by using the
existing private field in the iomap_iter, and add the argument to
iomap_file_buffered_write.  This will allow us to pass the file in
through the iomap buffered write path, and is flexible for any other
file systems needs.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/7f55c7c32275004ba00cddf862d970e6e633f750.1724755651.git.josef@toxicpanda.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-03 15:01:23 +02:00
Luis Chamberlain
d1dd75dcda iomap: remove set_memor_ro() on zero page
Stephen reported a boot failure on ppc power8 system where
set_memor_ro() on the new zero page failed [0]. Christophe Leroy
further clarifies we can't use this on on linear memory on ppc, and
so instead of special casing this just for PowerPC [2] remove the
call as suggested by Darrick.

[0] https://lore.kernel.org/all/20240826175931.1989f99e@canb.auug.org.au/T/#u
[1] https://lore.kernel.org/all/b0fe75b4-c1bb-47f7-a7c3-2534b31c1780@csgroup.eu/
[2] https://lore.kernel.org/all/ZszrJkFOpiy5rCma@bombadil.infradead.org/

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Suggested-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20240826212632.2098685-1-mcgrof@kernel.org
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-03 15:01:23 +02:00
Pankaj Raghav
10553a9165 iomap: fix iomap_dio_zero() for fs bs > system page size
iomap_dio_zero() will pad a fs block with zeroes if the direct IO size
< fs block size. iomap_dio_zero() has an implicit assumption that fs block
size < page_size. This is true for most filesystems at the moment.

If the block size > page size, this will send the contents of the page
next to zero page(as len > PAGE_SIZE) to the underlying block device,
causing FS corruption.

iomap is a generic infrastructure and it should not make any assumptions
about the fs block size and the page size of the system.

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
Link: https://lore.kernel.org/r/20240822135018.1931258-7-kernel@pankajraghav.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-09-02 16:19:43 +02:00
Matthew Wilcox (Oracle)
97edbc02b2
buffer: Convert block_write_end() to take a folio
All callers now have a folio, so pass it in instead of converting
from a folio to a page and back to a folio again.  Saves a call
to compound_head().

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-08-07 11:31:59 +02:00
Linus Torvalds
4f5e249ec0 vfs-6.11.iomap
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Merge tag 'vfs-6.11.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull iomap updates from Christian Brauner:
 "This contains some minor work for the iomap subsystem:

   - Add documentation on the design of iomap and how to port to it

   - Optimize iomap_read_folio()

   - Bring back the change to iomap_write_end() to no increase i_size.

     This is accompanied by a change to xfs to reserve blocks for
     truncating large realtime inodes to avoid exposing stale data when
     iomap_write_end() stops increasing i_size"

* tag 'vfs-6.11.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  iomap: don't increase i_size in iomap_write_end()
  xfs: reserve blocks for truncating large realtime inode
  Documentation: the design of iomap and how to port
  iomap: Optimize iomap_read_folio
2024-07-15 13:28:14 -07:00
Linus Torvalds
aff31330e0 vfs-6.11.pg_error
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Merge tag 'vfs-6.11.pg_error' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs

Pull PG_error removal updates from Christian Brauner:
 "This contains work to remove almost all remaining users of PG_error
  from filesystems and filesystem helper libraries. An additional patch
  will be coming in via the jfs tree which tests the PG_error bit.

  Afterwards nothing will be testing it anymore and it's safe to remove
  all places which set or clear the PG_error bit.

  The goal is to fully remove PG_error by the next merge window"

* tag 'vfs-6.11.pg_error' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  buffer: Remove calls to set and clear the folio error flag
  iomap: Remove calls to set and clear folio error flag
  vboxsf: Convert vboxsf_read_folio() to use a folio
  ufs: Remove call to set the folio error flag
  romfs: Convert romfs_read_folio() to use a folio
  reiserfs: Remove call to folio_set_error()
  orangefs: Remove calls to set/clear the error flag
  nfs: Remove calls to folio_set_error
  jffs2: Remove calls to set/clear the folio error flag
  hostfs: Convert hostfs_read_folio() to use a folio
  isofs: Convert rock_ridge_symlink_read_folio to use a folio
  hpfs: Convert hpfs_symlink_read_folio to use a folio
  efs: Convert efs_symlink_read_folio to use a folio
  cramfs: Convert cramfs_read_folio to use a folio
  coda: Convert coda_symlink_filler() to use folio_end_read()
  befs: Convert befs_symlink_read_folio() to use folio_end_read()
2024-07-15 11:08:14 -07:00
Zhang Yi
602f09f402
iomap: don't increase i_size in iomap_write_end()
This reverts commit '0841ea4a3b41 ("iomap: keep on increasing i_size in
iomap_write_end()")'.

After xfs could zero out the tail blocks aligned to the allocation
unitsize and convert the tail blocks to unwritten for realtime inode on
truncate down, it couldn't expose any stale data when unaligned truncate
down realtime inodes, so we could keep on keeping i_size for
IOMAP_UNSHARE and IOMAP_ZERO in iomap_write_end().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240618142112.1315279-3-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-19 15:58:28 +02:00
Ritesh Harjani (IBM)
af4eb6f46f
iomap: Optimize iomap_read_folio
iomap_readpage_iter() handles "uptodate blocks" and "not uptodate blocks"
within a folio separately. This makes iomap_read_folio() to call into
->iomap_begin() to request for extent mapping even though it might already
have an extent which is not fully processed.
This happens when we either have a large folio or with bs < ps. In these
cases we can have sub blocks which can be uptodate (say for e.g. due to
previous writes). With iomap_read_folio_iter(), this is handled more
efficiently by not calling ->iomap_begin() call until all the sub blocks
with the current folio are processed.

iomap_read_folio_iter() handles multiple sub blocks within a given
folio but it's implementation logic is similar to how
iomap_readahead_iter() handles multiple folios within a single mapped
extent. Both of them iterate over a given range of folio/mapped extent
and call iomap_readpage_iter() for reading.

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/92ae9f3333c9a7e66214568d08f45664261c899c.1715067055.git.ritesh.list@gmail.com
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-19 15:58:19 +02:00
Ritesh Harjani (IBM)
f5ceb1bbc9 iomap: Fix iomap_adjust_read_range for plen calculation
If the extent spans the block that contains i_size, we need to handle
both halves separately so that we properly zero data in the page cache
for blocks that are entirely outside of i_size. But this is needed only
when i_size is within the current folio under processing.
"orig_pos + length > isize" can be true for all folios if the mapped
extent length is greater than the folio size. That is making plen to
break for every folio instead of only the last folio.

So use orig_plen for checking if "orig_pos + orig_plen > isize".

Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Link: https://lore.kernel.org/r/a32e5f9a4fcfdb99077300c4020ed7ae61d6e0f9.1715067055.git.ritesh.list@gmail.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
cc: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-05 17:27:03 +02:00
Zhang Yi
0841ea4a3b iomap: keep on increasing i_size in iomap_write_end()
Commit '943bc0882ceb ("iomap: don't increase i_size if it's not a write
operation")' breaks xfs with realtime device on generic/561, the problem
is when unaligned truncate down a xfs realtime inode with rtextsize > 1
fs block, xfs only zero out the EOF block but doesn't zero out the tail
blocks that aligned to rtextsize, so if we don't increase i_size in
iomap_write_end(), it could expose stale data after we do an append
write beyond the aligned EOF block.

xfs should zero out the tail blocks when truncate down, but before we
finish that, let's fix the issue by just revert the changes in
iomap_write_end().

Fixes: 943bc0882c ("iomap: don't increase i_size if it's not a write operation")
Reported-by: Chandan Babu R <chandanbabu@kernel.org>
Link: https://lore.kernel.org/linux-xfs/0b92a215-9d9b-3788-4504-a520778953c2@huaweicloud.com
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240603112222.2109341-1-yi.zhang@huaweicloud.com
Tested-by: Chandan Babu R <chandanbabu@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-06-05 17:23:39 +02:00
Matthew Wilcox (Oracle)
1f56eedf7f
iomap: Remove calls to set and clear folio error flag
The folio error flag is not checked anywhere, so we can remove the calls
to set and clear it.

Cc: Christian Brauner <brauner@kernel.org>
Cc: linux-xfs@vger.kernel.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20240530202110.2653630-16-willy@infradead.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-05-31 12:31:42 +02:00
Xu Yang
4e527d5841 iomap: fault in smaller chunks for non-large folio mappings
Since commit (5d8edfb900 "iomap: Copy larger chunks from userspace"),
iomap will try to copy in larger chunks than PAGE_SIZE. However, if the
mapping doesn't support large folio, only one page of maximum 4KB will
be created and 4KB data will be writen to pagecache each time. Then,
next 4KB will be handled in next iteration. This will cause potential
write performance problem.

If chunk is 2MB, total 512 pages need to be handled finally. During this
period, fault_in_iov_iter_readable() is called to check iov_iter readable
validity. Since only 4KB will be handled each time, below address space
will be checked over and over again:

start         	end
-
buf,    	buf+2MB
buf+4KB, 	buf+2MB
buf+8KB, 	buf+2MB
...
buf+2044KB 	buf+2MB

Obviously the checking size is wrong since only 4KB will be handled each
time. So this will get a correct chunk to let iomap work well in non-large
folio case.

With this change, the write speed will be stable. Tested on ARM64 device.

Before:

 - dd if=/dev/zero of=/dev/sda bs=400K  count=10485  (334 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=800K  count=5242   (278 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=1600K count=2621   (204 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=2200K count=1906   (170 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=3000K count=1398   (150 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=4500K count=932    (139 MB/s)

After:

 - dd if=/dev/zero of=/dev/sda bs=400K  count=10485  (339 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=800K  count=5242   (330 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=1600K count=2621   (332 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=2200K count=1906   (333 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=3000K count=1398   (333 MB/s)
 - dd if=/dev/zero of=/dev/sda bs=4500K count=932    (333 MB/s)

Fixes: 5d8edfb900 ("iomap: Copy larger chunks from userspace")
Cc: stable@vger.kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Link: https://lore.kernel.org/r/20240521114939.2541461-2-xu.yang_2@nxp.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-05-24 13:34:07 +02:00
Linus Torvalds
ff9a79307f Kbuild updates for v6.10
- Avoid 'constexpr', which is a keyword in C23
 
  - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
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  - Fix weak references to avoid GOT entries in position-independent
    code generation
 
  - Convert the last use of 'optional' property in arch/sh/Kconfig
 
  - Remove support for the 'optional' property in Kconfig
 
  - Remove support for Clang's ThinLTO caching, which does not work with
    the .incbin directive
 
  - Change the semantics of $(src) so it always points to the source
    directory, which fixes Makefile inconsistencies between upstream and
    downstream
 
  - Fix 'make tar-pkg' for RISC-V to produce a consistent package
 
  - Provide reasonable default coverage for objtool, sanitizers, and
    profilers
 
  - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.
 
  - Remove the last use of tristate choice in drivers/rapidio/Kconfig
 
  - Various cleanups and fixes in Kconfig
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Merge tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Avoid 'constexpr', which is a keyword in C23

 - Allow 'dtbs_check' and 'dt_compatible_check' run independently of
   'dt_binding_check'

 - Fix weak references to avoid GOT entries in position-independent code
   generation

 - Convert the last use of 'optional' property in arch/sh/Kconfig

 - Remove support for the 'optional' property in Kconfig

 - Remove support for Clang's ThinLTO caching, which does not work with
   the .incbin directive

 - Change the semantics of $(src) so it always points to the source
   directory, which fixes Makefile inconsistencies between upstream and
   downstream

 - Fix 'make tar-pkg' for RISC-V to produce a consistent package

 - Provide reasonable default coverage for objtool, sanitizers, and
   profilers

 - Remove redundant OBJECT_FILES_NON_STANDARD, KASAN_SANITIZE, etc.

 - Remove the last use of tristate choice in drivers/rapidio/Kconfig

 - Various cleanups and fixes in Kconfig

* tag 'kbuild-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (46 commits)
  kconfig: use sym_get_choice_menu() in sym_check_prop()
  rapidio: remove choice for enumeration
  kconfig: lxdialog: remove initialization with A_NORMAL
  kconfig: m/nconf: merge two item_add_str() calls
  kconfig: m/nconf: remove dead code to display value of bool choice
  kconfig: m/nconf: remove dead code to display children of choice members
  kconfig: gconf: show checkbox for choice correctly
  kbuild: use GCOV_PROFILE and KCSAN_SANITIZE in scripts/Makefile.modfinal
  Makefile: remove redundant tool coverage variables
  kbuild: provide reasonable defaults for tool coverage
  modules: Drop the .export_symbol section from the final modules
  kconfig: use menu_list_for_each_sym() in sym_check_choice_deps()
  kconfig: use sym_get_choice_menu() in conf_write_defconfig()
  kconfig: add sym_get_choice_menu() helper
  kconfig: turn defaults and additional prompt for choice members into error
  kconfig: turn missing prompt for choice members into error
  kconfig: turn conf_choice() into void function
  kconfig: use linked list in sym_set_changed()
  kconfig: gconf: use MENU_CHANGED instead of SYMBOL_CHANGED
  kconfig: gconf: remove debug code
  ...
2024-05-18 12:39:20 -07:00
Masahiro Yamada
b1992c3772 kbuild: use $(src) instead of $(srctree)/$(src) for source directory
Kbuild conventionally uses $(obj)/ for generated files, and $(src)/ for
checked-in source files. It is merely a convention without any functional
difference. In fact, $(obj) and $(src) are exactly the same, as defined
in scripts/Makefile.build:

    src := $(obj)

When the kernel is built in a separate output directory, $(src) does
not accurately reflect the source directory location. While Kbuild
resolves this discrepancy by specifying VPATH=$(srctree) to search for
source files, it does not cover all cases. For example, when adding a
header search path for local headers, -I$(srctree)/$(src) is typically
passed to the compiler.

This introduces inconsistency between upstream and downstream Makefiles
because $(src) is used instead of $(srctree)/$(src) for the latter.

To address this inconsistency, this commit changes the semantics of
$(src) so that it always points to the directory in the source tree.

Going forward, the variables used in Makefiles will have the following
meanings:

  $(obj)     - directory in the object tree
  $(src)     - directory in the source tree  (changed by this commit)
  $(objtree) - the top of the kernel object tree
  $(srctree) - the top of the kernel source tree

Consequently, $(srctree)/$(src) in upstream Makefiles need to be replaced
with $(src).

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2024-05-10 04:34:52 +09:00
Zhang Yi
e1f453d433
iomap: do some small logical cleanup in buffered write
Since iomap_write_end() can never return a partial write length, the
comparison between written, copied and bytes becomes useless, just
merge them with the unwritten branch.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-10-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
815f4b633b
iomap: make iomap_write_end() return a boolean
For now, we can make sure iomap_write_end() always return 0 or copied
bytes, so instead of return written bytes, convert to return a boolean
to indicate the copied bytes have been written to the pagecache.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-9-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
1a61d74932
iomap: use a new variable to handle the written bytes in iomap_write_iter()
In iomap_write_iter(), the status variable used to receive the return
value from iomap_write_end() is confusing, replace it with a new written
variable to represent the written bytes in each cycle, no logic changes.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-8-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
943bc0882c
iomap: don't increase i_size if it's not a write operation
Increase i_size in iomap_zero_range() and iomap_unshare_iter() is not
needed, the caller should handle it. Especially, when truncate partial
block, we should not increase i_size beyond the new EOF here. It doesn't
affect xfs and gfs2 now because they set the new file size after zero
out, it doesn't matter that a transient increase in i_size, but it will
affect ext4 because it set file size before truncate. So move the i_size
updating logic to iomap_write_iter().

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-7-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:54 +02:00
Zhang Yi
89c6c1d91a
iomap: drop the write failure handles when unsharing and zeroing
Unsharing and zeroing can only happen within EOF, so there is never a
need to perform posteof pagecache truncation if write begin fails, also
partial write could never theoretically happened from iomap_write_end(),
so remove both of them.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240320110548.2200662-6-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-25 14:23:53 +02:00
Christoph Hellwig
0fac04e4e0
iomap: convert iomap_writepages to writeack_iter
This removes one indirect function call per folio, and adds type safety
by not casting through a void pointer.

Based on a patch by Matthew Wilcox.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240412061614.1511629-1-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-04-15 14:25:55 +02:00
Christian Brauner
86835c39e0 vfs-6.9.rw_hint
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Merge tag 'vfs-6.9.rw_hint' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs

Pull write hint fix from Christian Brauner:

UFS devices are widely used in mobile applications, e.g. in smartphones.
UFS vendors need data lifetime information to achieve good performance.
Providing data lifetime information to UFS devices can result in up to
40% lower write amplification. Hence this patch series that restores the
bi_write_hint member in struct bio. After this patch series has been
merged, patches that implement data lifetime support in the SCSI disk
(sd) driver will be sent to the Linux kernel SCSI maintainer.

The following changes are included in this patch series:

- Improvements for the F_GET_RW_HINT and F_SET_RW_HINT fcntls.
- Move enum rw_hint into a new header file.
- Support F_SET_RW_HINT for block devices to make it easy to test data
  lifetime support.
- Restore the bio.bi_write_hint member and restore support in the VFS
  layer and also in the block layer for data lifetime information.

The shell script that has been used to test the patch series combined
with the SCSI patches is available at the end of this cover letter.

* tag 'vfs-6.9.rw_hint' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
  block, fs: Restore the per-bio/request data lifetime fields
  fs: Propagate write hints to the struct block_device inode
  fs: Move enum rw_hint into a new header file
  fs: Split fcntl_rw_hint()
  fs: Verify write lifetime constants at compile time
  fs: Fix rw_hint validation

Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-03-04 18:35:21 +01:00
Kassey Li
dcd04ea587 iomap: Add processed for iomap_iter
processed: The number of bytes processed by the body in the
most recent  iteration, or a negative errno. 0 causes the iteration to
stop.

The processed is useful to check when the loop breaks.

Signed-off-by: Kassey Li <quic_yingangl@quicinc.com>
Link: https://lore.kernel.org/r/20240219021138.3481763-1-quic_yingangl@quicinc.com
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-21 08:37:50 +01:00
Zhang Yi
54943abce0 iomap: add pos and dirty_len into trace_iomap_writepage_map
Since commit fd07e0aa23c4 ("iomap: map multiple blocks at a time"), we
could map multi-blocks once a time, and the dirty_len indicates the
expected map length, map_len won't large than it. The pos and dirty_len
means the dirty range that should be mapped to write, add them into
trace_iomap_writepage_map() could be more useful for debug.

Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20240220115759.3445025-1-yi.zhang@huaweicloud.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-21 08:35:20 +01:00
Bart Van Assche
449813515d
block, fs: Restore the per-bio/request data lifetime fields
Restore support for passing data lifetime information from filesystems to
block drivers. This patch reverts commit b179c98f76 ("block: Remove
request.write_hint") and commit c75e707fe1 ("block: remove the
per-bio/request write hint").

This patch does not modify the size of struct bio because the new
bi_write_hint member fills a hole in struct bio. pahole reports the
following for struct bio on an x86_64 system with this patch applied:

        /* size: 112, cachelines: 2, members: 20 */
        /* sum members: 110, holes: 1, sum holes: 2 */
        /* last cacheline: 48 bytes */

Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20240202203926.2478590-7-bvanassche@acm.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-06 14:31:05 +01:00
Christoph Hellwig
19871b5c7a iomap: pass the length of the dirty region to ->map_blocks
Let the file system know how much dirty data exists at the passed
in offset.  This allows file systems to allocate the right amount
of space that actually is written back if they can't eagerly
convert (e.g. because they don't support unwritten extents).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-15-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
30deff8531 iomap: map multiple blocks at a time
The ->map_blocks interface returns a valid range for writeback, but we
still call back into it for every block, which is a bit inefficient.

Change iomap_writepage_map to use the valid range in the map until the
end of the folio or the dirty range inside the folio instead of calling
back into every block.

Note that the range is not used over folio boundaries as we need to be
able to check the mapping sequence count under the folio lock.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-14-hch@lst.de
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
410bb2ce61 iomap: submit ioends immediately
Currently the writeback code delays submitting fill ioends until we
reach the end of the folio.  The reason for that is that otherwise
the end I/O handler could clear the writeback bit before we've even
finished submitting all I/O for the folio.

Add a bias to ifs->write_bytes_pending while we are submitting I/O
for a folio so that it never reaches zero until all I/O is completed
to prevent the early writeback bit clearing, and remove the now
superfluous submit_list.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-13-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:13 +01:00
Christoph Hellwig
f525152a0f iomap: factor out a iomap_writepage_map_block helper
Split the loop body that calls into the file system to map a block and
add it to the ioend into a separate helper to prefer for refactoring of
the surrounding code.

Note that this was the only place in iomap_writepage_map that could
return an error, so include the call to ->discard_folio into the new
helper as that will help to avoid code duplication in the future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-12-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
6b865d6530 iomap: only call mapping_set_error once for each failed bio
Instead of clling mapping_set_error once per folio, only do that once
per bio, and consolidate all the writeback error handling code in
iomap_finish_ioend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-11-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
ae5535efd8 iomap: don't chain bios
Back in the days when a single bio could only be filled to the hardware
limits, and we scheduled a work item for each bio completion, chaining
multiple bios for a single ioend made a lot of sense to reduce the number
of completions.  But these days bios can be filled until we reach the
number of vectors or total size limit, which means we can always fit at
least 1 megabyte worth of data in the worst case, but usually a lot more
due to large folios.  The only thing bio chaining is buying us now is
to reduce the size of the allocation from an ioend with an embedded bio
into a plain bio, which is a 52 bytes differences on 64-bit systems.

This is not worth the added complexity, so remove the bio chaining and
only use the bio embedded into the ioend.  This will help to simplify
further changes to the iomap writeback code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-10-hch@lst.de
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
dec3a7b3aa iomap: move the iomap_sector sector calculation out of iomap_add_to_ioend
The calculation in iomap_sector is pretty trivial and most of the time
iomap_add_to_ioend only callers either iomap_can_add_to_ioend or
iomap_alloc_ioend from a single invocation.

Calculate the sector in the two lower level functions and stop passing it
from iomap_add_to_ioend and update the iomap_alloc_ioend argument passing
order to match that of iomap_add_to_ioend.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-9-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:12 +01:00
Christoph Hellwig
7edfc610ec iomap: clean up the iomap_alloc_ioend calling convention
Switch to the same argument order as iomap_writepage_map and remove the
ifs argument that can be trivially recalculated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-8-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
cc9542534b iomap: move all remaining per-folio logic into iomap_writepage_map
Move the tracepoint and the iomap check from iomap_do_writepage into
iomap_writepage_map.  This keeps all logic in one places, and leaves
iomap_do_writepage just as the wrapper for the callback conventions of
write_cache_pages, which will go away when that is converted to an
iterator.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-7-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00
Christoph Hellwig
e3a491a26b iomap: factor out a iomap_writepage_handle_eof helper
Most of iomap_do_writepage is dedidcated to handling a folio crossing or
beyond i_size.  Split this is into a separate helper and update the
commens to deal with folios instead of pages and make them more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231207072710.176093-6-hch@lst.de
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
2024-02-01 14:20:11 +01:00