linux.git/fs/squashfs, branch v6.0

squashfs: don't call kmalloc in decompressors

2022-08-28T21:02:45+00:00

The decompressors may be called while in an atomic section.  So move the
kmalloc() out of this path, and into the "page actor" init function.

This fixes a regression introduced by commit
f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")

Link: https://lkml.kernel.org/r/20220822215430.15933-1-phillip@squashfs.org.uk
Fixes: f268eedddf35 ("squashfs: extend "page actor" to handle missing pages")
Reported-by: Chris Murphy 
Signed-off-by: Phillip Lougher 
Cc: 
Signed-off-by: Andrew Morton

Merge tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-08-07T17:03:24+00:00

Pull misc updates from Andrew Morton:
 "Updates to various subsystems which I help look after. lib, ocfs2,
  fatfs, autofs, squashfs, procfs, etc. A relatively small amount of
  material this time"

* tag 'mm-nonmm-stable-2022-08-06-2' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (72 commits)
  scripts/gdb: ensure the absolute path is generated on initial source
  MAINTAINERS: kunit: add David Gow as a maintainer of KUnit
  mailmap: add linux.dev alias for Brendan Higgins
  mailmap: update Kirill's email
  profile: setup_profiling_timer() is moslty not implemented
  ocfs2: fix a typo in a comment
  ocfs2: use the bitmap API to simplify code
  ocfs2: remove some useless functions
  lib/mpi: fix typo 'the the' in comment
  proc: add some (hopefully) insightful comments
  bdi: remove enum wb_congested_state
  kernel/hung_task: fix address space of proc_dohung_task_timeout_secs
  lib/lzo/lzo1x_compress.c: replace ternary operator with min() and min_t()
  squashfs: support reading fragments in readahead call
  squashfs: implement readahead
  squashfs: always build "file direct" version of page actor
  Revert "squashfs: provide backing_dev_info in order to disable read-ahead"
  fs/ocfs2: Fix spelling typo in comment
  ia64: old_rr4 added under CONFIG_HUGETLB_PAGE
  proc: fix test for "vsyscall=xonly" boot option
  ...

squashfs: Return the actual error from squashfs_read_folio()

2022-08-02T16:34:02+00:00

Since we actually know what error happened, we can report it instead
of having the generic code return -EIO for pages that were unlocked
without being marked uptodate.  Also remove a test of PageError since
we have the return value at this point.

Signed-off-by: Matthew Wilcox (Oracle)

squashfs: support reading fragments in readahead call

2022-07-30T01:12:34+00:00

Add a function which can be used to read fragments in the readahead call.

This function is necessary because filesystems built with the -tailends
(or -always-use-fragments) option may have fragments present which cannot
be currently handled.

Link: https://lkml.kernel.org/r/20220617083810.337573-5-hsinyi@chromium.org
Signed-off-by: Phillip Lougher 
Signed-off-by: Hsin-Yi Wang 
Cc: Hou Tao 
Cc: kernel test robot 
Cc: Marek Szyprowski 
Cc: Matthew Wilcox 
Cc: Miao Xie 
Cc: Xiongwei Song 
Cc: Zhang Yi 
Cc: Zheng Liang 
Signed-off-by: Andrew Morton

squashfs: implement readahead

2022-07-30T01:12:34+00:00

Implement readahead callback for squashfs.  It will read datablocks which
cover pages in readahead request.  For a few cases it will not mark page
as uptodate, including:

- file end is 0.
- zero filled blocks.
- current batch of pages isn't in the same datablock.
- decompressor error.

Otherwise pages will be marked as uptodate.  The unhandled pages will be
updated by readpage later.

Link: https://lkml.kernel.org/r/20220617083810.337573-4-hsinyi@chromium.org
Signed-off-by: Hsin-Yi Wang 
Suggested-by: Matthew Wilcox 
Reported-by: Matthew Wilcox 
Reported-by: Phillip Lougher 
Reported-by: Xiongwei Song 
Reported-by: Andrew Morton 
Cc: Hou Tao 
Cc: kernel test robot 
Cc: Marek Szyprowski 
Cc: Miao Xie 
Cc: Zhang Yi 
Cc: Zheng Liang 
Signed-off-by: Andrew Morton

squashfs: always build "file direct" version of page actor

2022-07-30T01:12:34+00:00

Squashfs_readahead uses the "file direct" version of the page actor, and
so build it unconditionally.

Link: https://lkml.kernel.org/r/20220617083810.337573-3-hsinyi@chromium.org
Signed-off-by: Phillip Lougher 
Signed-off-by: Hsin-Yi Wang 
Reported-by: kernel test robot 
Cc: Hou Tao 
Cc: Marek Szyprowski 
Cc: Matthew Wilcox 
Cc: Miao Xie 
Cc: Xiongwei Song 
Cc: Zhang Yi 
Cc: Zheng Liang 
Signed-off-by: Andrew Morton

Revert "squashfs: provide backing_dev_info in order to disable read-ahead"

2022-07-30T01:12:34+00:00

Patch series "Implement readahead for squashfs", v7.

Commit 9eec1d897139("squashfs: provide backing_dev_info in order to
disable read-ahead") mitigates the performance drop issue for squashfs by
closing readahead for it.

This series implements readahead callback for squashfs.


This patch (of 4):

This reverts 9eec1d897139e5 ("squashfs: provide backing_dev_info in order
to disable read-ahead").

Revert closing the readahead to squashfs since the readahead callback for
squashfs is implemented.

Link: https://lkml.kernel.org/r/20220617083810.337573-1-hsinyi@chromium.org
Link: https://lkml.kernel.org/r/20220617083810.337573-2-hsinyi@chromium.org
Signed-off-by: Hsin-Yi Wang 
Suggested-by: Xiongwei Song 
Cc: Phillip Lougher 
Cc: Matthew Wilcox 
Cc: Marek Szyprowski 
Cc: Zheng Liang 
Cc: Zhang Yi 
Cc: Hou Tao 
Cc: Miao Xie 

Cc: kernel test robot 
Signed-off-by: Andrew Morton

squashfs: don't use intermediate buffer if pages missing

2022-06-17T02:58:22+00:00

Now that the "page actor" can handle missing pages, we don't have to fall
back to using an intermediate buffer in Squashfs_readpage_block() if all
the pages necessary can't be obtained.

Link: https://lkml.kernel.org/r/20220611032133.5743-3-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher 
Cc: Hsin-Yi Wang 
Cc: Matthew Wilcox (Oracle) 
Cc: Xiongwei Song 
Signed-off-by: Andrew Morton

squashfs: extend "page actor" to handle missing pages

2022-06-17T02:58:21+00:00

Patch series "Squashfs: handle missing pages decompressing into page
cache".

This patchset enables Squashfs to handle missing pages when directly
decompressing datablocks into the page cache.

Previously if the full set of pages needed was not available, Squashfs
would have to fall back to using an intermediate buffer (the older
method), which is slower, involving a memcopy, and it introduces
contention on a shared buffer.

The first patch extends the "page actor" code to handle missing pages.

The second patch updates Squashfs_readpage_block() to use the new
functionality, and removes the code that falls back to using an
intermediate buffer.

This patchset is independent of the readahead work, and it is standalone. 
It can be merged on its own.

But the readahead patch for efficiency also needs this patch-set.


This patch (of 2):

This patch extends the "page actor" code to handle missing pages.

Previously if the full set of pages needed to decompress a Squashfs
datablock was unavailable, this would cause decompression to fail on the
missing pages.

In this case direct decompression into the page cache could not be
achieved and the code would fall back to using the older intermediate
buffer method.

With this patch, direct decompression into the page cache can be achieved
with missing pages.

For "multi-shot" decompressors (zlib, xz, zstd), the page actor will
allocate a temporary buffer which is passed to the decompressor, and then
freed by the page actor.

For "single shot" decompressors (lz4, lzo) which decompress into a
contiguous "bounce buffer", and which is then copied into the page cache,
it would be pointless to allocate a temporary buffer, memcpy into it, and
then free it.  For these decompressors -ENOMEM is returned, which
signifies that the memcpy for that page should be skipped.

This also happens if the data block is uncompressed.

Link: https://lkml.kernel.org/r/20220611032133.5743-1-phillip@squashfs.org.uk
Link: https://lkml.kernel.org/r/20220611032133.5743-2-phillip@squashfs.org.uk
Signed-off-by: Phillip Lougher 
Cc: Matthew Wilcox (Oracle) 
Cc: Hsin-Yi Wang 
Cc: Xiongwei Song 
Signed-off-by: Andrew Morton

Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache

2022-05-25T02:55:07+00:00

Pull page cache updates from Matthew Wilcox:

 - Appoint myself page cache maintainer

 - Fix how scsicam uses the page cache

 - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS

 - Remove the AOP flags entirely

 - Remove pagecache_write_begin() and pagecache_write_end()

 - Documentation updates

 - Convert several address_space operations to use folios:
     - is_dirty_writeback
     - readpage becomes read_folio
     - releasepage becomes release_folio
     - freepage becomes free_folio

 - Change filler_t to require a struct file pointer be the first
   argument like ->read_folio

* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
  nilfs2: Fix some kernel-doc comments
  Appoint myself page cache maintainer
  fs: Remove aops->freepage
  secretmem: Convert to free_folio
  nfs: Convert to free_folio
  orangefs: Convert to free_folio
  fs: Add free_folio address space operation
  fs: Convert drop_buffers() to use a folio
  fs: Change try_to_free_buffers() to take a folio
  jbd2: Convert release_buffer_page() to use a folio
  jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
  reiserfs: Convert release_buffer_page() to use a folio
  fs: Remove last vestiges of releasepage
  ubifs: Convert to release_folio
  reiserfs: Convert to release_folio
  orangefs: Convert to release_folio
  ocfs2: Convert to release_folio
  nilfs2: Remove comment about releasepage
  nfs: Convert to release_folio
  jfs: Convert to release_folio
  ...