linux-toradex.git/fs/afs/dir.c, branch v6.7

afs: Fix setting of mtime when creating a file/dir/symlink

2023-06-07T16:03:12+00:00

kafs incorrectly passes a zero mtime (ie. 1st Jan 1970) to the server when
creating a file, dir or symlink because the mtime recorded in the
afs_operation struct gets passed to the server by the marshalling routines,
but the afs_mkdir(), afs_create() and afs_symlink() functions don't set it.

This gets masked if a file or directory is subsequently modified.

Fix this by filling in op->mtime before calling the create op.

Fixes: e49c7b2f6de7 ("afs: Build an abstraction around an "operation" concept")
Signed-off-by: David Howells 
Reviewed-by: Jeffrey Altman 
Reviewed-by: Marc Dionne 
cc: linux-afs@lists.infradead.org
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Linus Torvalds

afs: Avoid endless loop if file is larger than expected

2023-05-02T16:23:50+00:00

afs_read_dir fetches an amount of data that's based on what the inode
size is thought to be.  If the file on the server is larger than what
was fetched, the code rechecks i_size and retries.  If the local i_size
was not properly updated, this can lead to an endless loop of fetching
i_size from the server and noticing each time that the size is larger on
the server.

If it is known that the remote size is larger than i_size, bump up the
fetch size to that size.

Fixes: f3ddee8dc4e2 ("afs: Fix directory handling")
Signed-off-by: Marc Dionne 
Signed-off-by: David Howells 
cc: linux-afs@lists.infradead.org

mm: return an ERR_PTR from __filemap_get_folio

2023-04-06T02:42:42+00:00

Instead of returning NULL for all errors, distinguish between:

 - no entry found and not asked to allocated (-ENOENT)
 - failed to allocate memory (-ENOMEM)
 - would block (-EAGAIN)

so that callers don't have to guess the error based on the passed in
flags.

Also pass through the error through the direct callers: filemap_get_folio,
filemap_lock_folio filemap_grab_folio and filemap_get_incore_folio.

[hch@lst.de: fix null-pointer deref]
  Link: https://lkml.kernel.org/r/20230310070023.GA13563@lst.de
  Link: https://lkml.kernel.org/r/20230310043137.GA1624890@u2004
Link: https://lkml.kernel.org/r/20230307143410.28031-8-hch@lst.de
Signed-off-by: Christoph Hellwig 
Acked-by: Ryusuke Konishi  [nilfs2]
Cc: Andreas Gruenbacher 
Cc: Hugh Dickins 
Cc: Matthew Wilcox (Oracle) 
Cc: Naoya Horiguchi 
Signed-off-by: Andrew Morton

fs: port ->rename() to pass mnt_idmap

2023-01-19T08:24:26+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->mkdir() to pass mnt_idmap

2023-01-19T08:24:26+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->symlink() to pass mnt_idmap

2023-01-19T08:24:25+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

fs: port ->create() to pass mnt_idmap

2023-01-19T08:24:25+00:00

Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b42 ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Christian Brauner (Microsoft)

afs: Stop implementing ->writepage()

2022-12-22T11:40:35+00:00

We're trying to get rid of the ->writepage() hook[1].  Stop afs from using
it by unlocking the page and calling afs_writepages_region() rather than
folio_write_one().

A flag is passed to afs_writepages_region() to indicate that it should only
write a single region so that we don't flush the entire file in
->write_begin(), but do add other dirty data to the region being written to
try and reduce the number of RPC ops.

This requires ->migrate_folio() to be implemented, so point that at
filemap_migrate_folio() for files and also for symlinks and directories.

This can be tested by turning on the afs_folio_dirty tracepoint and then
doing something like:

   xfs_io -c "w 2223 7000" -c "w 15000 22222" -c "w 23 7" /afs/my/test/foo

and then looking in the trace to see if the write at position 15000 gets
stored before page 0 gets dirtied for the write at position 23.

Signed-off-by: David Howells 
cc: Marc Dionne 
cc: Christoph Hellwig 
cc: Matthew Wilcox 
cc: linux-afs@lists.infradead.org
Link: https://lore.kernel.org/r/20221113162902.883850-1-hch@lst.de/ [1]
Link: https://lore.kernel.org/r/166876785552.222254.4403222906022558715.stgit@warthog.procyon.org.uk/ # v1

use less confusing names for iov_iter direction initializers

2022-11-25T18:01:55+00:00

READ/WRITE proved to be actively confusing - the meanings are
"data destination, as used with read(2)" and "data source, as
used with write(2)", but people keep interpreting those as
"we read data from it" and "we write data to it", i.e. exactly
the wrong way.

Call them ITER_DEST and ITER_SOURCE - at least that is harder
to misinterpret...

Signed-off-by: Al Viro

Change calling conventions for filldir_t

2022-08-17T21:25:04+00:00

filldir_t instances (directory iterators callbacks) used to return 0 for
"OK, keep going" or -E... for "stop".  Note that it's *NOT* how the
error values are reported - the rules for those are callback-dependent
and ->iterate{,_shared}() instances only care about zero vs. non-zero
(look at emit_dir() and friends).

So let's just return bool ("should we keep going?") - it's less confusing
that way.  The choice between "true means keep going" and "true means
stop" is bikesheddable; we have two groups of callbacks -
	do something for everything in directory, until we run into problem
and
	find an entry in directory and do something to it.

The former tended to use 0/-E... conventions - -E on failure.
The latter tended to use 0/1, 1 being "stop, we are done".
The callers treated anything non-zero as "stop", ignoring which
non-zero value did they get.

"true means stop" would be more natural for the second group; "true
means keep going" - for the first one.  I tried both variants and
the things like
	if allocation failed
		something = -ENOMEM;
		return true;
just looked unnatural and asking for trouble.

[folded suggestion from Matthew Wilcox ]
Acked-by: Christian Brauner (Microsoft) 
Signed-off-by: Al Viro