linux-toradex.git/fs/xfs/xfs_mru_cache.c, branch v5.17

xfs: rename _zone variables to _cache

2021-10-22T23:04:20+00:00

Now that we've gotten rid of the kmem_zone_t typedef, rename the
variables to _cache since that's what they are.

Signed-off-by: Darrick J. Wong 
Reviewed-by: Chandan Babu R

xfs: set WQ_SYSFS on all workqueues in debug mode

2021-02-03T17:18:49+00:00

When CONFIG_XFS_DEBUG=y, set WQ_SYSFS on all workqueues that we create
so that we (developers) have a means to monitor cpu affinity and whatnot
for background workers.  In the next patchset we'll expose knobs for
more of the workqueues publicly and document it, but not now.

Signed-off-by: Darrick J. Wong 
Reviewed-by: Dave Chinner 
Reviewed-by: Brian Foster

fs: xfs: Remove KM_NOSLEEP and KM_SLEEP.

2019-08-26T19:06:22+00:00

Since no caller is using KM_NOSLEEP and no callee branches on KM_SLEEP,
we can remove KM_NOSLEEP and replace KM_SLEEP with 0.

Signed-off-by: Tetsuo Handa 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

xfs: convert to SPDX license tags

2018-06-06T21:17:53+00:00

Remove the verbose license text from XFS files and replace them
with SPDX tags. This does not change the license of any of the code,
merely refers to the common, up-to-date license files in LICENSES/

This change was mostly scripted. fs/xfs/Makefile and
fs/xfs/libxfs/xfs_fs.h were modified by hand, the rest were detected
and modified by the following command:

for f in `git grep -l "GNU General" fs/xfs/` ; do
	echo $f
	cat $f | awk -f hdr.awk > $f.new
	mv -f $f.new $f
done

And the hdr.awk script that did the modification (including
detecting the difference between GPL-2.0 and GPL-2.0+ licenses)
is as follows:

$ cat hdr.awk
BEGIN {
	hdr = 1.0
	tag = "GPL-2.0"
	str = ""
}

/^ \* This program is free software/ {
	hdr = 2.0;
	next
}

/any later version./ {
	tag = "GPL-2.0+"
	next
}

/^ \*\// {
	if (hdr > 0.0) {
		print "// SPDX-License-Identifier: " tag
		print str
		print $0
		str=""
		hdr = 0.0
		next
	}
	print $0
	next
}

/^ \* / {
	if (hdr > 1.0)
		next
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
	next
}

/^ \*/ {
	if (hdr > 0.0)
		next
	print $0
	next
}

// {
	if (hdr > 0.0) {
		if (str != "")
			str = str "\n"
		str = str $0
		next
	}
	print $0
}

END { }
$

Signed-off-by: Dave Chinner 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

xfs: remove filestream item xfs_inode reference

2018-04-09T17:23:39+00:00

The filestreams allocator stores an xfs_fstrm_item structure in the MRU to
cache inode number to agno mappings for a particular length of time.  Each
xfs_fstrm_item contains the internal MRU structure, an inode pointer and
agno value.

The inode pointer stored in the xfs_fstrm_item is not referenced, however,
which means the inode itself can be removed and reclaimed before the MRU
item is freed. If this occurs, xfs_fstrm_free_func() can access freed or
unrelated memory through xfs_fstrm_item->ip and crash.

The obvious solution is to grab an inode reference for xfs_fstrm_item.
The filestream mechanism only actually uses the inode pointer as a means
to access the xfs_mount, however.  Rather than add unnecessary
complexity, simplify the implementation to store an xfs_mount pointer in
struct xfs_mru_cache, and pass it to the free callback.  This also
requires updates to the tracepoint class to provide the associated data
via parameters rather than the inode and a minor hack to peek at the MRU
key to establish the inode number at free time.

Based on debugging work and an earlier patch from Brian Foster, who
also wrote most of this changelog.

Reported-by: Brian Foster 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Brian Foster 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

xfs: xfs_mru_cache_insert() should use GFP_NOFS

2015-03-25T03:57:53+00:00

xfs_mru_cache_insert() can be called from within transaction context
during block allocation like so:

write(2)
  ....
    xfs_get_blocks
      xfs_iomap_write_direct
        start transaction
        xfs_bmapi_write
          xfs_bmapi_allocate
            xfs_bmap_btalloc
              xfs_bmap_btalloc_filestreams
                xfs_filestream_new_ag
                  xfs_filestream_pick_ag
                    xfs_mru_cache_insert
                      radix_tree_preload(GFP_KERNEL)

In this case, GFP_KERNEL is incorrect and can potentially lead to
deadlocks in memory reclaim. It should use GFP_NOFS allocations to
avoid lock recursion problems.

[dchinner: rewrote commit message]

Signed-off-by: Byoungyoung Lee 
Signed-off-by: Sanidhya Kashyap 
Reviewed-by: Dave Chinner 
Signed-off-by: Dave Chinner

xfs: mark all internal workqueues as freezable

2014-09-09T01:44:46+00:00

Workqueues must be explicitly set as freezable to ensure they are frozen
in the assocated part of the hibernation/suspend sequence. Freezing of
workqueues and kernel threads is important to ensure that modifications
are not made on-disk after the hibernation image has been created.
Otherwise, the in-memory state can become inconsistent with what is on
disk and eventually lead to filesystem corruption. We have reports of
free space btree corruptions that occur immediately after restore from
hibernate that suggest the xfs-eofblocks workqueue could be causing
such problems if it races with hibernation.

Mark all of the internal XFS workqueues as freezable to ensure nothing
changes on-disk once the freezer infrastructure freezes kernel threads
and creates the hibernation image.

Signed-off-by: Brian Foster 
Reported-by: Carlos E. R. 
Reviewed-by: Dave Chinner 
Signed-off-by: Dave Chinner

xfs: global error sign conversion

2014-06-25T04:58:08+00:00

Convert all the errors the core XFs code to negative error signs
like the rest of the kernel and remove all the sign conversion we
do in the interface layers.

Errors for conversion (and comparison) found via searches like:

$ git grep " E" fs/xfs
$ git grep "return E" fs/xfs
$ git grep " E[A-Z].*;$" fs/xfs

Negation points found via searches like:

$ git grep "= -[a-z,A-Z]" fs/xfs
$ git grep "return -[a-z,A-D,F-Z]" fs/xfs
$ git grep " -[a-z].*;" fs/xfs

[ with some bits I missed from Brian Foster ]

Signed-off-by: Dave Chinner 
Reviewed-by: Brian Foster 
Signed-off-by: Dave Chinner

xfs: embedd mru_elem into parent structure

2014-04-22T21:11:51+00:00

There is no need to do a separate allocation for each mru element, just
embedd the structure into the parent one in the user.  Besides saving
a memory allocation and the infrastructure required for it this also
simplifies the API.

While we do major surgery on xfs_mru_cache.c also de-typedef it and
make struct mru_cache private to the implementation file.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Signed-off-by: Dave Chinner

xfs: handle duplicate entries in xfs_mru_cache_insert

2014-04-22T21:11:50+00:00

The radix tree code can detect and reject duplicate keys at insert
time.  Make xfs_mru_cache_insert handle this case so that future
changes to the filestream allocator can take advantage of this.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Signed-off-by: Dave Chinner