linux.git/fs/fuse/file.c, branch v5.19

fuse: Convert fuse to read_folio

2022-05-09T20:21:45+00:00

This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.

Signed-off-by: Matthew Wilcox (Oracle)

fs: Remove flags parameter from aops->write_begin

2022-05-08T18:28:19+00:00

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig

fs: Remove aop flags parameter from grab_cache_page_write_begin()

2022-05-08T18:28:19+00:00

There are no more aop flags left, so remove the parameter.

Signed-off-by: Matthew Wilcox (Oracle) 
Reviewed-by: Christoph Hellwig

Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache

2022-03-23T01:26:56+00:00

Pull filesystem folio updates from Matthew Wilcox:
 "Primarily this series converts some of the address_space operations to
  take a folio instead of a page.

  Notably:

   - a_ops->is_partially_uptodate() takes a folio instead of a page and
     changes the type of the 'from' and 'count' arguments to make it
     obvious they're bytes.

   - a_ops->invalidatepage() becomes ->invalidate_folio() and has a
     similar type change.

   - a_ops->launder_page() becomes ->launder_folio()

   - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
     address_space as an argument.

  There are a couple of other misc changes up front that weren't worth
  separating into their own pull request"

* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
  fs: Remove aops ->set_page_dirty
  fb_defio: Use noop_dirty_folio()
  fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
  fs: Convert __set_page_dirty_buffers to block_dirty_folio
  nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
  mm: Convert swap_set_page_dirty() to swap_dirty_folio()
  ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
  f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
  f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
  f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
  afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
  btrfs: Convert extent_range_redirty_for_io() to use folios
  fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
  btrfs: Convert from set_page_dirty to dirty_folio
  fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
  fs: Add aops->dirty_folio
  fs: Remove aops->launder_page
  orangefs: Convert launder_page to launder_folio
  nfs: Convert from launder_page to launder_folio
  fuse: Convert from launder_page to launder_folio
  ...

fuse: remove reliance on bdi congestion

2022-03-22T22:57:00+00:00

The bdi congestion tracking in not widely used and will be removed.

Fuse is one of a small number of filesystems that uses it, setting both
the sync (read) and async (write) congestion flags at what it determines
are appropriate times.

The only remaining effect of the sync flag is to cause read-ahead to be
skipped.  The only remaining effect of the async flag is to cause (some)
WB_SYNC_NONE writes to be skipped.

So instead of setting the flags, change:

 - .readahead to stop when it has submitted all non-async pages for
   read.

 - .writepages to do nothing if WB_SYNC_NONE and the flag would be set

 - .writepage to return AOP_WRITEPAGE_ACTIVATE if WB_SYNC_NONE and the
   flag would be set.

The writepages change causes a behavioural change in that pageout() can
now return PAGE_ACTIVATE instead of PAGE_KEEP, so SetPageActive() will be
called on the page which (I think) will further delay the next attempt at
writeout.  This might be a good thing.

Link: https://lkml.kernel.org/r/164549983737.9187.2627117501000365074.stgit@noble.brown
Signed-off-by: NeilBrown 
Cc: Anna Schumaker 
Cc: Chao Yu 
Cc: Darrick J. Wong 
Cc: Ilya Dryomov 
Cc: Jaegeuk Kim 
Cc: Jan Kara 
Cc: Jeff Layton 
Cc: Jens Axboe 
Cc: Lars Ellenberg 
Cc: Miklos Szeredi 
Cc: Paolo Valente 
Cc: Philipp Reisner 
Cc: Ryusuke Konishi 
Cc: Trond Myklebust 
Cc: Wu Fengguang 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio

2022-03-15T12:34:38+00:00

These filesystems use __set_page_dirty_nobuffers() either directly or
with a very thin wrapper; convert them en masse.

Signed-off-by: Matthew Wilcox (Oracle) 
Tested-by: Damien Le Moal 
Acked-by: Damien Le Moal 
Tested-by: Mike Marshall  # orangefs
Tested-by: David Howells  # afs

fuse: Convert from launder_page to launder_folio

2022-03-15T12:23:30+00:00

Straightforward conversion although the helper functions still assume
a single page.

Signed-off-by: Matthew Wilcox (Oracle) 
Tested-by: Damien Le Moal 
Acked-by: Damien Le Moal 
Tested-by: Mike Marshall  # orangefs
Tested-by: David Howells  # afs

fuse: fix pipe buffer lifetime for direct_io

2022-03-07T15:30:44+00:00

In FOPEN_DIRECT_IO mode, fuse_file_write_iter() calls
fuse_direct_write_iter(), which normally calls fuse_direct_io(), which then
imports the write buffer with fuse_get_user_pages(), which uses
iov_iter_get_pages() to grab references to userspace pages instead of
actually copying memory.

On the filesystem device side, these pages can then either be read to
userspace (via fuse_dev_read()), or splice()d over into a pipe using
fuse_dev_splice_read() as pipe buffers with &nosteal_pipe_buf_ops.

This is wrong because after fuse_dev_do_read() unlocks the FUSE request,
the userspace filesystem can mark the request as completed, causing write()
to return. At that point, the userspace filesystem should no longer have
access to the pipe buffer.

Fix by copying pages coming from the user address space to new pipe
buffers.

Reported-by: Jann Horn 
Fixes: c3021629a0d8 ("fuse: support splice() reading from fuse device")
Cc: 
Signed-off-by: Miklos Szeredi

fuse: enable per inode DAX

2021-12-14T10:09:37+00:00

DAX may be limited in some specific situation. When the number of usable
DAX windows is under watermark, the recalim routine will be triggered to
reclaim some DAX windows. It may have a negative impact on the
performance, since some processes may need to wait for DAX windows to be
recalimed and reused then. To mitigate the performance degradation, the
overall DAX window need to be expanded larger.

However, simply expanding the DAX window may not be a good deal in some
scenario. To maintain one DAX window chunk (i.e., 2MB in size), 32KB
(512 * 64 bytes) memory footprint will be consumed for page descriptors
inside guest, which is greater than the memory footprint if it uses
guest page cache when DAX disabled. Thus it'd better disable DAX for
those files smaller than 32KB, to reduce the demand for DAX window and
thus avoid the unworthy memory overhead.

Per inode DAX feature is introduced to address this issue, by offering a
finer grained control for dax to users, trying to achieve a balance
between performance and memory overhead.

The FUSE_ATTR_DAX flag in FUSE_LOOKUP reply is used to indicate whether
DAX should be enabled or not for corresponding file. Currently the state
whether DAX is enabled or not for the file is initialized only when
inode is instantiated.

Signed-off-by: Jeffle Xu 
Reviewed-by: Vivek Goyal 
Signed-off-by: Miklos Szeredi

fuse: Pass correct lend value to filemap_write_and_wait_range()

2021-12-07T14:20:16+00:00

The acceptable maximum value of lend parameter in
filemap_write_and_wait_range() is LLONG_MAX rather than -1. And there is
also some logic depending on LLONG_MAX check in write_cache_pages(). So
let's pass LLONG_MAX to filemap_write_and_wait_range() in
fuse_writeback_range() instead.

Fixes: 59bda8ecee2f ("fuse: flush extending writes")
Signed-off-by: Xie Yongji 
Cc:  # v5.15
Signed-off-by: Miklos Szeredi