linux.git/fs/f2fs/data.c, branch v5.17

mm: remove cleancache

2022-01-22T06:33:38+00:00

Patch series "remove Xen tmem leftovers".

Since the removal of the Xen tmem driver in 2019, the cleancache hooks
are entirely unused, as are large parts of frontswap.  This series
against linux-next (with the folio changes included) removes
cleancaches, and cuts down frontswap to the bits actually used by zswap.

This patch (of 13):

The cleancache subsystem is unused since the removal of Xen tmem driver
in commit 814bbf49dcd0 ("xen: remove tmem driver").

[akpm@linux-foundation.org: remove now-unreachable code]

Link: https://lkml.kernel.org/r/20211224062246.1258487-1-hch@lst.de
Link: https://lkml.kernel.org/r/20211224062246.1258487-2-hch@lst.de
Signed-off-by: Christoph Hellwig 
Reviewed-by: Juergen Gross 
Acked-by: Geert Uytterhoeven 
Cc: Konrad Rzeszutek Wilk 
Cc: Hugh Dickins 
Cc: Seth Jennings 
Cc: Dan Streetman 
Cc: Vitaly Wool 
Cc: Matthew Wilcox (Oracle) 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs

2022-01-19T09:50:20+00:00

Pull f2fs updates from Jaegeuk Kim:
 "In this round, we've tried to address some performance issues in
  f2fs_checkpoint and direct IO flows. Also, there was a work to enhance
  the page cache management used for compression. Other than them, we've
  done typical work including sysfs, code clean-ups, tracepoint, sanity
  check, in addition to bug fixes on corner cases.

  Enhancements:
   - use iomap for direct IO
   - try to avoid lock contention to improve f2fs_ckpt speed
   - avoid unnecessary memory allocation in compression flow
   - POSIX_FADV_DONTNEED drops the page cache containing compression
     pages
   - add some sysfs entries (gc_urgent_high_remaining, pending_discard)

  Bug fixes:
   - try not to expose unwritten blocks to user by DIO (this was added
     to avoid merge conflict; another patch is coming to address other
     missing case)
   - relax minor error condition for file pinning feature used in
     Android OTA
   - fix potential deadlock case in compression flow
   - should not truncate any block on pinned file

  In addition, we've done some code clean-ups and tracepoint/sanity
  check improvement"

* tag 'f2fs-for-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (29 commits)
  f2fs: do not allow partial truncation on pinned file
  f2fs: remove redunant invalidate compress pages
  f2fs: Simplify bool conversion
  f2fs: don't drop compressed page cache in .{invalidate,release}page
  f2fs: fix to reserve space for IO align feature
  f2fs: fix to check available space of CP area correctly in update_ckpt_flags()
  f2fs: support fault injection to f2fs_trylock_op()
  f2fs: clean up __find_inline_xattr() with __find_xattr()
  f2fs: fix to do sanity check on last xattr entry in __f2fs_setxattr()
  f2fs: do not bother checkpoint by f2fs_get_node_info
  f2fs: avoid down_write on nat_tree_lock during checkpoint
  f2fs: compress: fix potential deadlock of compress file
  f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file
  f2fs: add gc_urgent_high_remaining sysfs node
  f2fs: fix to do sanity check in is_alive()
  f2fs: fix to avoid panic in is_alive() if metadata is inconsistent
  f2fs: fix to do sanity check on inode type during garbage collection
  f2fs: avoid duplicate call of mark_inode_dirty
  f2fs: show number of pending discard commands
  f2fs: support POSIX_FADV_DONTNEED drop compressed page cache
  ...

mm: introduce memalloc_retry_wait()

2022-01-15T14:30:29+00:00

Various places in the kernel - largely in filesystems - respond to a
memory allocation failure by looping around and re-trying.  Some of
these cannot conveniently use __GFP_NOFAIL, for reasons such as:

 - a GFP_ATOMIC allocation, which __GFP_NOFAIL doesn't work on
 - a need to check for the process being signalled between failures
 - the possibility that other recovery actions could be performed
 - the allocation is quite deep in support code, and passing down an
   extra flag to say if __GFP_NOFAIL is wanted would be clumsy.

Many of these currently use congestion_wait() which (in almost all
cases) simply waits the given timeout - congestion isn't tracked for
most devices.

It isn't clear what the best delay is for loops, but it is clear that
the various filesystems shouldn't be responsible for choosing a timeout.

This patch introduces memalloc_retry_wait() with takes on that
responsibility.  Code that wants to retry a memory allocation can call
this function passing the GFP flags that were used.  It will wait
however is appropriate.

For now, it only considers __GFP_NORETRY and whatever
gfpflags_allow_blocking() tests.  If blocking is allowed without
__GFP_NORETRY, then alloc_page either made some reclaim progress, or
waited for a while, before failing.  So there is no need for much
further waiting.  memalloc_retry_wait() will wait until the current
jiffie ends.  If this condition is not met, then alloc_page() won't have
waited much if at all.  In that case memalloc_retry_wait() waits about
200ms.  This is the delay that most current loops uses.

linux/sched/mm.h needs to be included in some files now,
but linux/backing-dev.h does not.

Link: https://lkml.kernel.org/r/163754371968.13692.1277530886009912421@noble.neil.brown.name
Signed-off-by: NeilBrown 
Cc: Dave Chinner 
Cc: Michal Hocko 
Cc: "Theodore Ts'o" 
Cc: Jaegeuk Kim 
Cc: Chao Yu 
Cc: Darrick J. Wong 
Cc: Chuck Lever 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

f2fs: don't drop compressed page cache in .{invalidate,release}page

2022-01-04T21:20:57+00:00

For compressed inode, in .{invalidate,release}page, we will call
f2fs_invalidate_compress_pages() to drop all compressed page cache of
current inode.

But we don't need to drop compressed page cache synchronously in
.invalidatepage, because, all trancation paths of compressed physical
block has been covered with f2fs_invalidate_compress_page().

And also we don't need to drop compressed page cache synchronously
in .releasepage, because, if there is out-of-memory, we can count
on page cache reclaim on sbi->compress_inode.

BTW, this patch may fix the issue reported below:

https://lore.kernel.org/linux-f2fs-devel/20211202092812.197647-1-changfengnan@vivo.com/T/#u

Signed-off-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: do not bother checkpoint by f2fs_get_node_info

2022-01-04T21:20:49+00:00

This patch tries to mitigate lock contention between f2fs_write_checkpoint and
f2fs_get_node_info along with nat_tree_lock.

The idea is, if checkpoint is currently running, other threads that try to grab
nat_tree_lock would be better to wait for checkpoint.

Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim

f2fs: avoid EINVAL by SBI_NEED_FSCK when pinning a file

2021-12-14T19:17:48+00:00

Android OTA failed due to SBI_NEED_FSCK flag when pinning the file. Let's avoid
it since we can do in-place-updates.

Cc: stable@vger.kernel.org
Signed-off-by: Jaegeuk Kim

f2fs: use iomap for direct I/O

2021-12-10T23:48:30+00:00

Make f2fs_file_read_iter() and f2fs_file_write_iter() use the iomap
direct I/O implementation instead of the fs/direct-io.c one.

The iomap implementation is more efficient, and it also avoids the need
to add new features and optimizations to the old implementation.

This new implementation also eliminates the need for f2fs to hook bio
submission and completion and to allocate memory per-bio.  This is
because it's possible to correctly update f2fs's in-flight DIO counters
using __iomap_dio_rw() in combination with an implementation of
iomap_dio_ops::end_io() (as suggested by Christoph Hellwig).

When possible, this new implementation preserves existing f2fs behavior
such as the conditions for falling back to buffered I/O.

This patch has been tested with xfstests by running 'gce-xfstests -c
f2fs -g auto -X generic/017' with and without this patch; no regressions
were seen.  (Some tests fail both before and after.  generic/017 hangs
both before and after, so it had to be excluded.)

Signed-off-by: Eric Biggers 
[Jaegeuk Kim: use spin_lock_bh for f2fs_update_iostat in softirq]
Signed-off-by: Jaegeuk Kim

f2fs: implement iomap operations

2021-12-04T18:53:35+00:00

Implement 'struct iomap_ops' for f2fs, in preparation for making f2fs
use iomap for direct I/O.

Note that this may be used for other things besides direct I/O in the
future; however, for now I've only tested it for direct I/O.

Signed-off-by: Eric Biggers 
Signed-off-by: Jaegeuk Kim

f2fs: do not expose unwritten blocks to user by DIO

2021-12-04T18:53:33+00:00

DIO preallocates physical blocks before writing data, but if an error occurrs
or power-cut happens, we can see block contents from the disk. This patch tries
to fix it by 1) turning to buffered writes for DIO into holes, 2) truncating
unwritten blocks from error or power-cut.

Signed-off-by: Jaegeuk Kim

f2fs: rework write preallocations

2021-11-17T19:28:22+00:00

f2fs_write_begin() assumes that all blocks were preallocated by
default unless FI_NO_PREALLOC is explicitly set.  This invites data
corruption, as there are cases in which not all blocks are preallocated.
Commit 47501f87c61a ("f2fs: preallocate DIO blocks when forcing
buffered_io") fixed one case, but there are others remaining.

Fix up this logic by replacing this flag with FI_PREALLOCATED_ALL, which
only gets set if all blocks for the current write were preallocated.

Also clean up f2fs_preallocate_blocks(), move it to file.c, and make it
handle some of the logic that was previously in write_iter() directly.

Signed-off-by: Eric Biggers 
Reviewed-by: Chao Yu 
Signed-off-by: Jaegeuk Kim