Commit Graph

3485 Commits

Author SHA1 Message Date
Dave Chinner
febe3cbe38 xfs: bulkstat error handling is broken
The error propagation is a horror - xfs_bulkstat() returns
a rval variable which is only set if there are formatter errors. Any
sort of btree walk error or corruption will cause the bulkstat walk
to terminate but will not pass an error back to userspace. Worse
is the fact that formatter errors will also be ignored if any inodes
were correctly formatted into the user buffer.

Hence bulkstat can fail badly yet still report success to userspace.
This causes significant issues with xfsdump not dumping everything
in the filesystem yet reporting success. It's not until a restore
fails that there is any indication that the dump was bad and tha
bulkstat failed. This patch now triggers xfsdump to fail with
bulkstat errors rather than silently missing files in the dump.

This now causes bulkstat to fail when the lastino cookie does not
fall inside an existing inode chunk. The pre-3.17 code tolerated
that error by allowing the code to move to the next inode chunk
as the agino target is guaranteed to fall into the next btree
record.

With the fixes up to this point in the series, xfsdump now passes on
the troublesome filesystem image that exposes all these bugs.

cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2014-11-07 08:31:15 +11:00
Dave Chinner
6e57c542cb xfs: bulkstat main loop logic is a mess
There are a bunch of variables tha tare more wildy scoped than they
need to be, obfuscated user buffer checks and tortured "next inode"
tracking. This all needs cleaning up to expose the real issues that
need fixing.

cc: <stable@vger.kernel.org> # 3.17
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-07 08:31:13 +11:00
Dave Chinner
2b831ac6bc xfs: bulkstat chunk-formatter has issues
The loop construct has issues:
	- clustidx is completely unused, so remove it.
	- the loop tries to be smart by terminating when the
	  "freecount" tells it that all inodes are free. Just drop
	  it as in most cases we have to scan all inodes in the
	  chunk anyway.
	- move the "user buffer left" condition check to the only
	  point where we consume space int eh user buffer.
	- move the initialisation of agino out of the loop, leaving
	  just a simple loop control logic using the clusteridx.

Also, double handling of the user buffer variables leads to problems
tracking the current state - use the cursor variables directly
rather than keeping local copies and then having to update the
cursor before returning.

cc: <stable@vger.kernel.org> # 3.17
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-07 08:30:58 +11:00
Dave Chinner
bf4a5af20d xfs: bulkstat chunk formatting cursor is broken
The xfs_bulkstat_agichunk formatting cursor takes buffer values from
the main loop and passes them via the structure to the chunk
formatter, and the writes the changed values back into the main loop
local variables. Unfortunately, this complex dance is full of corner
cases that aren't handled correctly.

The biggest problem is that it is double handling the information in
both the main loop and the chunk formatting function, leading to
inconsistent updates and endless loops where progress is not made.

To fix this, push the struct xfs_bulkstat_agichunk outwards to be
the primary holder of user buffer information. this removes the
double handling in the main loop.

Also, pass the last inode processed by the chunk formatter as a
separate parameter as it purely an output variable and is not
related to the user buffer consumption cursor.

Finally, the chunk formatting code is not shared by anyone, so make
it local to xfs_itable.c.

cc: <stable@vger.kernel.org> # 3.17
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-07 08:30:30 +11:00
Dave Chinner
afa947cb52 xfs: bulkstat btree walk doesn't terminate
The bulkstat code has several different ways of detecting the end of
an AG when doing a walk. They are not consistently detected, and the
code that checks for the end of AG conditions is not consistently
coded. Hence the are conditions where the walk code can get stuck in
an endless loop making no progress and not triggering any
termination conditions.

Convert all the "tmp/i" status return codes from btree operations
to a common name (stat) and apply end-of-ag detection to these
operations consistently.

cc: <stable@vger.kernel.org> # 3.17
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-07 08:29:57 +11:00
Brian Foster
5d11fb4b9a xfs: rework zero range to prevent invalid i_size updates
The zero range operation is analogous to fallocate with the exception of
converting the range to zeroes. E.g., it attempts to allocate zeroed
blocks over the range specified by the caller. The XFS implementation
kills all delalloc blocks currently over the aligned range, converts the
range to allocated zero blocks (unwritten extents) and handles the
partial pages at the ends of the range by sending writes through the
pagecache.

The current implementation suffers from several problems associated with
inode size. If the aligned range covers an extending I/O, said I/O is
discarded and an inode size update from a previous write never makes it
to disk. Further, if an unaligned zero range extends beyond eof, the
page write induced for the partial end page can itself increase the
inode size, even if the zero range request is not supposed to update
i_size (via KEEP_SIZE, similar to an fallocate beyond EOF).

The latter behavior not only incorrectly increases the inode size, but
can lead to stray delalloc blocks on the inode. Typically, post-eof
preallocation blocks are either truncated on release or inode eviction
or explicitly written to by xfs_zero_eof() on natural file size
extension. If the inode size increases due to zero range, however,
associated blocks leak into the address space having never been
converted or mapped to pagecache pages. A direct I/O to such an
uncovered range cannot convert the extent via writeback and will BUG().
For example:

$ xfs_io -fc "pwrite 0 128k" -c "fzero -k 1m 54321" <file>
...
$ xfs_io -d -c "pread 128k 128k" <file>
<BUG>

If the entire delalloc extent happens to not have page coverage
whatsoever (e.g., delalloc conversion couldn't find a large enough free
space extent), even a full file writeback won't convert what's left of
the extent and we'll assert on inode eviction.

Rework xfs_zero_file_space() to avoid buffered I/O for partial pages.
Use the existing hole punch and prealloc mechanisms as primitives for
zero range. This implementation is not efficient nor ideal as we
writeback dirty data over the range and remove existing extents rather
than convert to unwrittern. The former writeback, however, is currently
the only mechanism available to ensure consistency between pagecache and
extent state. Even a pagecache truncate/delalloc punch prior to hole
punch has lead to inconsistencies due to racing with writeback.

This provides a consistent, correct implementation of zero range that
survives fsstress/fsx testing without assert failures. The
implementation can be optimized from this point forward once the
fundamental issue of pagecache and delalloc extent state consistency is
addressed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-30 10:35:11 +11:00
Jan Kara
7a19dee116 xfs: Check error during inode btree iteration in xfs_bulkstat()
xfs_bulkstat() doesn't check error return from xfs_btree_increment(). In
case of specific fs corruption that could result in xfs_bulkstat()
entering an infinite loop because we would be looping over the same
chunk over and over again. Fix the problem by checking the return value
and terminating the loop properly.

Coverity-id: 1231338
cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jie Liu <jeff.u.liu@gmail.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-30 10:34:52 +11:00
Dave Chinner
a6bbce54ef xfs: bulkstat doesn't release AGI buffer on error
The recent refactoring of the bulkstat code left a small landmine in
the code. If a inobt read fails, then the tree walk is aborted and
returns without releasing the AGI buffer or freeing the cursor. This
can lead to a subsequent bulkstat call hanging trying to grab the
AGI buffer again.

cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-29 08:22:18 +11:00
Linus Torvalds
d3dc366bba Merge branch 'for-3.18/core' of git://git.kernel.dk/linux-block
Pull core block layer changes from Jens Axboe:
 "This is the core block IO pull request for 3.18.  Apart from the new
  and improved flush machinery for blk-mq, this is all mostly bug fixes
  and cleanups.

   - blk-mq timeout updates and fixes from Christoph.

   - Removal of REQ_END, also from Christoph.  We pass it through the
     ->queue_rq() hook for blk-mq instead, freeing up one of the request
     bits.  The space was overly tight on 32-bit, so Martin also killed
     REQ_KERNEL since it's no longer used.

   - blk integrity updates and fixes from Martin and Gu Zheng.

   - Update to the flush machinery for blk-mq from Ming Lei.  Now we
     have a per hardware context flush request, which both cleans up the
     code should scale better for flush intensive workloads on blk-mq.

   - Improve the error printing, from Rob Elliott.

   - Backing device improvements and cleanups from Tejun.

   - Fixup of a misplaced rq_complete() tracepoint from Hannes.

   - Make blk_get_request() return error pointers, fixing up issues
     where we NULL deref when a device goes bad or missing.  From Joe
     Lawrence.

   - Prep work for drastically reducing the memory consumption of dm
     devices from Junichi Nomura.  This allows creating clone bio sets
     without preallocating a lot of memory.

   - Fix a blk-mq hang on certain combinations of queue depths and
     hardware queues from me.

   - Limit memory consumption for blk-mq devices for crash dump
     scenarios and drivers that use crazy high depths (certain SCSI
     shared tag setups).  We now just use a single queue and limited
     depth for that"

* 'for-3.18/core' of git://git.kernel.dk/linux-block: (58 commits)
  block: Remove REQ_KERNEL
  blk-mq: allocate cpumask on the home node
  bio-integrity: remove the needless fail handle of bip_slab creating
  block: include func name in __get_request prints
  block: make blk_update_request print prefix match ratelimited prefix
  blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio
  block: fix alignment_offset math that assumes io_min is a power-of-2
  blk-mq: Make bt_clear_tag() easier to read
  blk-mq: fix potential hang if rolling wakeup depth is too high
  block: add bioset_create_nobvec()
  block: use bio_clone_fast() in blk_rq_prep_clone()
  block: misplaced rq_complete tracepoint
  sd: Honor block layer integrity handling flags
  block: Replace strnicmp with strncasecmp
  block: Add T10 Protection Information functions
  block: Don't merge requests if integrity flags differ
  block: Integrity checksum flag
  block: Relocate bio integrity flags
  block: Add a disk flag to block integrity profile
  block: Add prefix to block integrity profile flags
  ...
2014-10-18 11:53:51 -07:00
Dave Chinner
6889e783cd Merge branch 'xfs-misc-fixes-for-3.18-3' into for-next 2014-10-13 10:22:45 +11:00
Eric Sandeen
a8b1ee8baf xfs: fix agno increment in xfs_inumbers() loop
caused a regression in xfs_inumbers, which in turn broke
xfsdump, causing incomplete dumps.

The loop in xfs_inumbers() needs to fill the user-supplied
buffers, and iterates via xfs_btree_increment, reading new
ags as needed.

But the first time through the loop, if xfs_btree_increment()
succeeds, we continue, which triggers the ++agno at the bottom
of the loop, and we skip to soon to the next ag - without
the proper setup under next_ag to read the next ag.

Fix this by removing the agno increment from the loop conditional,
and only increment agno if we have actually hit the code under
the next_ag: target.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-13 10:21:53 +11:00
Mark Tinguely
52177937e9 xfs: xfs_iflush_done checks the wrong log item callback
Commit 3013683 ("xfs: remove all the inodes on a buffer from the AIL
in bulk") made the xfs inode flush callback more efficient by
combining all the inode writes on the buffer and the deletions of
the inode log item from AIL.

The initial loop in this patch should be looping through all
the log items on the buffer to see which items have
xfs_iflush_done as their callback function. But currently,
only the log item passed to the function has its callback
compared to xfs_iflush_done. If the log item pointer passed to
the function does have the xfs_iflush_done callback function,
then all the log items on the buffer are removed from the
li_bio_list on the buffer b_fspriv and could be removed from
the AIL even though they may have not been written yet.

This problem is masked by the fact that currently all inodes on a
buffer will have the same calback function - either xfs_iflush_done
or xfs_istale_done - and hence the bug cannot manifest in any way.
Still, we need to remove the landmine so that if we add new
callbacks in future this doesn't cause us problems.

Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-03 09:09:50 +10:00
Brian Foster
da5f10969d xfs: flush the range before zero range conversion
XFS currently discards delalloc blocks within the target range of a
zero range request. Unaligned start and end offsets are zeroed
through the page cache and the internal, aligned blocks are
converted to unwritten extents.

If EOF is page aligned and covered by a delayed allocation extent.
The inode size is not updated until I/O completion. If a zero range
request discards a delalloc range that covers page aligned EOF as
such, the inode size update never occurs. For example:

$ rm -f /mnt/file
$ xfs_io -fc "pwrite 0 64k" -c "zero 60k 4k" /mnt/file
$ stat -c "%s" /mnt/file
65536
$ umount /mnt
$ mount <dev> /mnt
$ stat -c "%s" /mnt/file
61440

Update xfs_zero_file_space() to flush the range rather than discard
delalloc blocks to ensure that inode size updates occur
appropriately.

[dchinner: Note that this is really a workaround to avoid the
underlying problems. More work is needed (and ongoing) to fix those
issues so this fix is being added as a temporary stop-gap measure. ]

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:44:54 +10:00
Brian Foster
07d08681d2 xfs: restore buffer_head unwritten bit on ioend cancel
xfs_vm_writepage() walks each buffer_head on the page, maps to the block
on disk and attaches to a running ioend structure that represents the
I/O submission. A new ioend is created when the type of I/O (unwritten,
delayed allocation or overwrite) required for a particular buffer_head
differs from the previous. If a buffer_head is a delalloc or unwritten
buffer, the associated bits are cleared by xfs_map_at_offset() once the
buffer_head is added to the ioend.

The process of mapping each buffer_head occurs in xfs_map_blocks() and
acquires the ilock in blocking or non-blocking mode, depending on the
type of writeback in progress. If the lock cannot be acquired for
non-blocking writeback, we cancel the ioend, redirty the page and
return. Writeback will revisit the page at some later point.

Note that we acquire the ilock for each buffer on the page. Therefore
during non-blocking writeback, it is possible to add an unwritten buffer
to the ioend, clear the unwritten state, fail to acquire the ilock when
mapping a subsequent buffer and cancel the ioend. If this occurs, the
unwritten status of the buffer sitting in the ioend has been lost. The
page will eventually hit writeback again, but xfs_vm_writepage() submits
overwrite I/O instead of unwritten I/O and does not perform unwritten
extent conversion at I/O completion. This leads to data corruption
because unwritten extents are treated as holes on reads and zeroes are
returned instead of reading from disk.

Modify xfs_cancel_ioend() to restore the buffer unwritten bit for ioends
of type XFS_IO_UNWRITTEN. This ensures that unwritten extent conversion
occurs once the page is eventually written back.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:42:06 +10:00
Eric Sandeen
5cca3f611d xfs: check for null dquot in xfs_quota_calc_throttle()
Coverity spotted this.

Granted, we *just* checked xfs_inod_dquot() in the caller (by
calling xfs_quota_need_throttle). However, this is the only place we
don't check the return value but the check is cheap and future-proof
so add it.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:27:09 +10:00
Eric Sandeen
04dd1a0d4b xfs: fix crc field handling in xfs_sb_to/from_disk
I discovered this in userspace, but the same change applies
to the kernel.

If we xfs_mdrestore an image from a non-crc filesystem, lo
and behold the restored image has gained a CRC:

# db/xfs_metadump.sh -o /dev/sdc1 - | xfs_mdrestore - test.img
# xfs_db -c "sb 0" -c "p crc" /dev/sdc1
crc = 0 (correct)
# xfs_db -c "sb 0" -c "p crc" test.img
crc = 0xb6f8d6a0 (correct)

This is because xfs_sb_from_disk doesn't fill in sb_crc,
but xfs_sb_to_disk(XFS_SB_ALL_BITS) does write the in-memory
CRC to disk - so we get uninitialized memory on disk.

Fix this by always initializing sb_crc to 0 when we read
the superblock, and masking out the CRC bit from ALL_BITS
when we write it.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:24:11 +10:00
Eric Sandeen
6ee49a20c1 xfs: don't send null bp to xfs_trans_brelse()
In this case, if bp is NULL, error is set, and we send a
NULL bp to xfs_trans_brelse, which will try to dereference it.

Test whether we actually have a buffer before we try to
free it.

Coverity spotted this.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:23:49 +10:00
Brian Foster
ce57bcf6b8 xfs: check for inode size overflow in xfs_new_eof()
If we write to the maximum file offset (2^63-2), XFS fails to log the
inode size update when the page is flushed. For example:

$ xfs_io -fc "pwrite `echo "2^63-1-1" | bc` 1" /mnt/file
wrote 1/1 bytes at offset 9223372036854775806
1.000000 bytes, 1 ops; 0.0000 sec (22.711 KiB/sec and 23255.8140 ops/sec)
$ stat -c %s /mnt/file
9223372036854775807
$ umount /mnt ; mount <dev> /mnt/
$ stat -c %s /mnt/file
0

This occurs because XFS calculates the new file size as io_offset +
io_size, I/O occurs in block sized requests, and the maximum supported
file size is not block aligned. Therefore, a write to the max allowable
offset on a 4k blocksize fs results in a write of size 4k to offset
2^63-4096 (e.g., equivalent to round_down(2^63-1, 4096), or IOW the
offset of the block that contains the max file size). The offset plus
size calculation (2^63 - 4096 + 4096 == 2^63) overflows the signed
64-bit variable which goes negative and causes the > comparison to the
on-disk inode size to fail. This returns 0 from xfs_new_eof() and
results in no change to the inode on-disk.

Update xfs_new_eof() to explicitly detect overflow of the local
calculation and use the VFS inode size in this scenario. The VFS inode
size is capped to the maximum and thus XFS writes the correct inode size
to disk.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:21:53 +10:00
Dave Chinner
a872703f34 xfs: only set extent size hint when asked
Currently the extent size hint is set unconditionally in
xfs_ioctl_setattr() when the FSX_EXTSIZE flag is set. Hence we can
set hints when the inode flags indicating the hint should be used
are not set.  Hence only set the extent size hint from userspace
when the inode has the XFS_DIFLAG_EXTSIZE flag set to indicate that
we should have an extent size hint set on the inode.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:20:30 +10:00
Dave Chinner
9336e3a765 xfs: project id inheritance is a directory only flag
xfs_set_diflags() allows it to be set on non-directory inodes, and
this flags errors in xfs_repair. Further, inode allocation allows
the same directory-only flag to be inherited to non-directories.
Make sure directory inode flags don't appear on other types of
inodes.

This fixes several xfstests scratch fileystem corruption reports
(e.g. xfs/050) now that xfstests checks scratch filesystems after
test completion.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:18:40 +10:00
Dave Chinner
e076b0f3a5 xfs: kill time.h
The typedef for timespecs and nanotime() are completely unnecessary,
and delay() can be moved to fs/xfs/linux.h, which means this file
can go away.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:18:13 +10:00
Dave Chinner
b1d6cc02f2 xfs: compat_xfs_bstat does not have forkoff
struct compat_xfs_bstat is missing the di_forkoff field and so does
not fully translate the structure correctly. Fix it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:17:58 +10:00
Dave Chinner
75e58ce4c8 Merge branch 'xfs-buf-iosubmit' into for-next 2014-10-02 09:11:14 +10:00
Christoph Hellwig
8c15612546 xfs: simplify xfs_zero_remaining_bytes
xfs_zero_remaining_bytes() open codes a log of buffer manupulations
to do a read forllowed by a write. It can simply be replaced by an
uncached read followed by a xfs_bwrite() call.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:05:44 +10:00
Dave Chinner
ba3726742c xfs: check xfs_buf_read_uncached returns correctly
xfs_buf_read_uncached() has two failure modes. If can either return
NULL or bp->b_error != 0 depending on the type of failure, and not
all callers check for both. Fix it so that xfs_buf_read_uncached()
always returns the error status, and the buffer is returned as a
function parameter. The buffer will only be returned on success.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:05:32 +10:00
Dave Chinner
595bff75dc xfs: introduce xfs_buf_submit[_wait]
There is a lot of cookie-cutter code that looks like:

	if (shutdown)
		handle buffer error
	xfs_buf_iorequest(bp)
	error = xfs_buf_iowait(bp)
	if (error)
		handle buffer error

spread through XFS. There's significant complexity now in
xfs_buf_iorequest() to specifically handle this sort of synchronous
IO pattern, but there's all sorts of nasty surprises in different
error handling code dependent on who owns the buffer references and
the locks.

Pull this pattern into a single helper, where we can hide all the
synchronous IO warts and hence make the error handling for all the
callers much saner. This removes the need for a special extra
reference to protect IO completion processing, as we can now hold a
single reference across dispatch and waiting, simplifying the sync
IO smeantics and error handling.

In doing this, also rename xfs_buf_iorequest to xfs_buf_submit and
make it explicitly handle on asynchronous IO. This forces all users
to be switched specifically to one interface or the other and
removes any ambiguity between how the interfaces are to be used. It
also means that xfs_buf_iowait() goes away.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:05:14 +10:00
Dave Chinner
8b131973d1 xfs: kill xfs_bioerror_relse
There is only one caller now - xfs_trans_read_buf_map() - and it has
very well defined call semantics - read, synchronous, and b_iodone
is NULL. Hence it's pretty clear what error handling is necessary
for this case. The bigger problem of untangling
xfs_trans_read_buf_map error handling is left to a future patch.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:05:05 +10:00
Dave Chinner
2718775469 xfs: xfs_bioerror can die.
Internal buffer write error handling is a mess due to the unnatural
split between xfs_bioerror and xfs_bioerror_relse().

xfs_bwrite() only does sync IO and determines the handler to
call based on b_iodone, so for this caller the only difference
between xfs_bioerror() and xfs_bioerror_release() is the XBF_DONE
flag. We don't care what the XBF_DONE flag state is because we stale
the buffer in both paths - the next buffer lookup will clear
XBF_DONE because XBF_STALE is set. Hence we can use common
error handling for xfs_bwrite().

__xfs_buf_delwri_submit() is a similar - it's only ever called
on writes - all sync or async - and again there's no reason to
handle them any differently at all.

Clean up the nasty error handling and remove xfs_bioerror().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:56 +10:00
Dave Chinner
8dac392198 xfs: kill xfs_bdstrat_cb
Only has two callers, and is just a shutdown check and error handler
around xfs_buf_iorequest. However, the error handling is a mess of
read and write semantics, and both internal callers only call it for
writes. Hence kill the wrapper, and follow up with a patch to
sanitise the error handling.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:40 +10:00
Dave Chinner
61be9c529a xfs: rework xfs_buf_bio_endio error handling
Currently the report of a bio error from completion
immediately marks the buffer with an error. The issue is that this
is racy w.r.t. synchronous IO - the submitter can see b_error being
set before the IO is complete, and hence we cannot differentiate
between submission failures and completion failures.

Add an internal b_io_error field protected by the b_lock to catch IO
completion errors, and only propagate that to the buffer during
final IO completion handling. Hence we can tell in xfs_buf_iorequest
if we've had a submission failure bey checking bp->b_error before
dropping our b_io_remaining reference - that reference will prevent
b_io_error values from being propagated to b_error in the event that
completion races with submission.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:31 +10:00
Dave Chinner
e8aaba9a78 xfs: xfs_buf_ioend and xfs_buf_iodone_work duplicate functionality
We do some work in xfs_buf_ioend, and some work in
xfs_buf_iodone_work, but much of that functionality is the same.
This work can all be done in a single function, leaving
xfs_buf_iodone just a wrapper to determine if we should execute it
by workqueue or directly. hence rename xfs_buf_iodone_work to
xfs_buf_ioend(), and add a new xfs_buf_ioend_async() for places that
need async processing.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:22 +10:00
Dave Chinner
e11bb8052c xfs: synchronous buffer IO needs a reference
When synchronous IO runs IO completion work, it does so without an
IO reference or a hold reference on the buffer. The IO "hold
reference" is owned by the submitter, and released when the
submission is complete. The IO reference is released when both the
submitter and the bio end_io processing is run, and so if the io
completion work is run from IO completion context, it is run without
an IO reference.

Hence we can get the situation where the submitter can submit the
IO, see an error on the buffer and unlock and free the buffer while
there is still IO in progress. This leads to use-after-free and
memory corruption.

Fix this by taking a "sync IO hold" reference that is owned by the
IO and not released until after the buffer completion calls are run
to wake up synchronous waiters. This means that the buffer will not
be freed in any circumstance until all IO processing is completed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:11 +10:00
Dave Chinner
cf53e99d19 xfs: Don't use xfs_buf_iowait in the delwri buffer code
For the special case of delwri buffer submission and waiting, we
don't need to issue IO synchronously at all. The second pass to call
xfs_buf_iowait() can be replaced with  blocking on xfs_buf_lock() -
the buffer will be unlocked when the async IO is complete.

This formalises a sane the method of waiting for async IO - take an
extra reference, submit the IO, call xfs_buf_lock() when you want to
wait for IO completion. i.e.:

	bp = xfs_buf_find();
	xfs_buf_hold(bp);
	bp->b_flags |= XBF_ASYNC;
	xfs_buf_iosubmit(bp);
	xfs_buf_lock(bp)
	error = bp->b_error;
	....
	xfs_buf_relse(bp);

While this is somewhat racy for gathering IO errors, none of the
code that calls xfs_buf_delwri_submit() will race against other
users of the buffers being submitted. Even if they do, we don't
really care if the error is detected by the delwri code or the user
we raced against. Either way, the error will be detected and
handled.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:04:01 +10:00
Dave Chinner
a870fe6dfa xfs: force the log before shutting down
When we have marked the filesystem for shutdown, we want to prevent
any further buffer IO from being submitted. However, we currently
force the log after marking the filesystem as shut down, hence
allowing IO to the log *after* we have marked both the filesystem
and the log as in an error state.

Clean this up by forcing the log before we mark the filesytem with
an error. This replaces the pure CIL flush that we currently have
which works around this same issue (i.e the CIL can't be flushed
once the shutdown flags are set) and hence enables us to clean up
the logic substantially.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-10-02 09:02:28 +10:00
Dave Chinner
bd438f825f Merge branch 'xfs-sparse-fixes' into for-next 2014-09-29 10:52:44 +10:00
Dave Chinner
b972d07971 xfs: annotate user variables passed as void
Some argument callbacks can contain user buffers, and sparse warns
about passing them as void pointers. Cast appropriately to remove
the sparse warnings.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 10:46:22 +10:00
Dave Chinner
e3aed1a081 xfs: xfs_kset should be static
As it is accessed through the struct xfs_mount and can be set up
entirely from fs/xfs/xfs_super.c

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 10:46:08 +10:00
Dave Chinner
bf1ed38330 xfs: xfs_qm_dquot_isolate needs locking annotations for sparse
To remove noise from the build.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 10:43:40 +10:00
Dave Chinner
e68ed77521 xfs: fix use of agi_newino in finobt lookup
Sparse warns that we are passing the big-endian valueo f agi_newino
to the initial btree lookup function when trying to find a new
inode. This is wrong - we need to pass the host order value, not the
disk order value. This will adversely affect the next inode
allocated, but given that the free inode btree is usually much
smaller than the allocated inode btree it is much less likely to be
a performance issue if we start the search in the wrong place.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 10:43:15 +10:00
Dave Chinner
2f43bbd96e Merge branch 'xfs-trans-recover-cleanup' into for-next 2014-09-29 10:00:24 +10:00
Dave Chinner
b818cca197 xfs: refactor recovery transaction start handling
Rework the transaction lookup and allocation code in
xlog_recovery_process_ophdr() to fold two related call-once
helper functions into a single helper. Then fold in all the
XLOG_START_TRANS logic to that helper to clean up the remaining
logic in xlog_recovery_process_ophdr().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 09:45:54 +10:00
Dave Chinner
7656066986 xfs: reorganise transaction recovery item code
The code for managing transactions anf the items for recovery is
spread across 3 different locations in the file. Move them all
together so that it is easy to read the code without needing to jump
long distances in the file.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 09:45:42 +10:00
Dave Chinner
88b863db97 xfs: fix double free in xlog_recover_commit_trans
When an error occurs during buffer submission in
xlog_recover_commit_trans(), we free the trans structure twice. Fix
it by only freeing the structure in the caller regardless of the
success or failure of the function.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 09:45:32 +10:00
Dave Chinner
e9131e50f9 xfs: recovery of XLOG_UNMOUNT_TRANS leaks memory
The XLOG_UNMOUNT_TRANS case skips the transaction, despite the fact
an unmount record is always in a standalone transaction. Hence
whenever we come across one of these we need to free the transaction
structure associated with it as there is no commit record that
follows it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 09:45:18 +10:00
Dave Chinner
eeb1168810 xfs: refactor xlog_recover_process_data()
Clean up xlog_recover_process_data() structure in preparation for
fixing the allocation and freeing context of the transaction being
recovered.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-29 09:45:03 +10:00
Dave Chinner
33044dc408 Merge branch 'xfs-misc-fixes-for-3.18-2' into for-next 2014-09-23 22:55:51 +10:00
Dave Chinner
2ebff7bbd7 xfs: flush entire last page of old EOF on truncate up
On a sub-page sized filesystem, truncating a mapped region down
leaves us in a world of hurt. We truncate the pagecache, zeroing the
newly unused tail, then punch blocks out from under the page. If we
then truncate the file back up immediately, we expose that unmapped
hole to a dirty page mapped into the user application, and that's
where it all goes wrong.

In truncating the page cache, we avoid unmapping the tail page of
the cache because it still contains valid data. The problem is that
it also contains a hole after the truncate, but nobody told the mm
subsystem that. Therefore, if the page is dirty before the truncate,
we'll never get a .page_mkwrite callout after we extend the file and
the application writes data into the hole on the page.  Hence when
we come to writing that region of the page, it has no blocks and no
delayed allocation reservation and hence we toss the data away.

This patch adds code to the truncate up case to solve it, by
ensuring the partial page at the old EOF is always cleaned after we
do any zeroing and move the EOF upwards. We can't actually serialise
the page writeback and truncate against page faults (yes, that
problem AGAIN) so this is really just a best effort and assumes it
is extremely unlikely that someone is concurrently writing to the
page at the EOF while extending the file.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 22:55:00 +10:00
Dave Chinner
7abbb8f928 xfs: xfs_swap_extent_flush can be static
Fix sparse warning introduced by commit 4ef897a ("xfs: flush both
inodes in xfs_swap_extents").

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 16:20:11 +10:00
Dave Chinner
02cc18764c xfs: xfs_buf_write_fail_rl_state can be static
Fix sparse warning introduced by commit ac8809f9 ("xfs: abort
metadata writeback on permanent errors").

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 16:15:45 +10:00
Fengguang Wu
ea95961df7 xfs: xfs_rtget_summary can be static
Fix sparse warning introduced by commit afabfd3 ("xfs: combine
xfs_rtmodify_summary and xfs_rtget_summary").

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 16:11:43 +10:00
Fabian Frederick
e3cf17962a xfs: remove second xfs_quota.h inclusion in xfs_icache.c
xfs_quota.h was included twice.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 16:05:55 +10:00
Eric Sandeen
fb04013156 xfs: don't ASSERT on corrupt ftype
xfs_dir3_data_get_ftype() gets the file type off disk, but ASSERTs
if it's invalid:

     ASSERT(type < XFS_DIR3_FT_MAX);

We shouldn't ASSERT on bad values read from disk.  V3 dirs are
CRC-protected, but V2 dirs + ftype are not.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 16:05:32 +10:00
Dave Chinner
8af3dcd3c8 xfs: xlog_cil_force_lsn doesn't always wait correctly
When running a tight mount/unmount loop on an older kernel, RedHat
QE found that unmount would occasionally hang in
xfs_buf_unpin_wait() on the superblock buffer. Tracing and other
debug work by Eric Sandeen indicated that it was hanging on the
writing of the superblock during unmount immediately after logging
the superblock counters in a synchronous transaction. Further debug
indicated that the synchronous transaction was not waiting for
completion correctly, and we narrowed it down to
xlog_cil_force_lsn() returning NULLCOMMITLSN and hence not pushing
the transaction in the iclog buffer to disk correctly.

While this unmount superblock write code is now very different in
mainline kernels, the xlog_cil_force_lsn() code is identical, and it
was bisected to the backport of commit f876e44 ("xfs: always do log
forces via the workqueue"). This commit made the CIL push
asynchronous for log forces and hence exposed a race condition that
couldn't occur on a synchronous push.

Essentially, the xlog_cil_force_lsn() relied implicitly on the fact
that the sequence push would be complete by the time
xlog_cil_push_now() returned, resulting in the context being pushed
being in the committing list. When it was made asynchronous, it was
recognised that there was a race condition in detecting whether an
asynchronous push has started or not and code was added to handle
it.

Unfortunately, the fix was not quite right and left a race condition
where it it would detect an empty CIL while a push was in progress
before the context had been added to the committing list. This was
incorrectly seen as a "nothing to do" condition and so would tell
xfs_log_force_lsn() that there is nothing to wait for, and hence it
would push the iclogbufs in memory.

The fix is simple, but explaining the logic and the race condition
is a lot more complex. The fix is to add the context to the
committing list before we start emptying the CIL. This allows us to
detect the difference between an empty "do nothing" push and a push
that has not started by adding a discrete "emptying the CIL" state
to avoid the transient, incorrect "empty" condition that the
(unchanged) waiting code was seeing.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:57:59 +10:00
Dave Chinner
f6d31f4b04 Merge branch 'xfs-shift-extents-rework' into for-next 2014-09-23 15:51:14 +10:00
Brian Foster
8b5279e33f xfs: only writeback and truncate pages for the freed range
xfs_free_file_space() only affects the range of the file for which space
is being freed. It currently writes and truncates the page cache from
the start offset of the free to EOF.

Modify xfs_free_file_space() to write back and truncate page cache of
just the range being freed.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:39:05 +10:00
Brian Foster
f71721d061 xfs: writeback and inval. file range to be shifted by collapse
The collapse range operation currently writes the entire file before
starting the collapse to avoid changes in the in-core extent list due to
writeback causing the extent count to change. Now that collapse range is
fsb based rather than extent index based it can sustain changes in the
extent list during the shift sequence without disruption.

Modify xfs_collapse_file_space() to writeback and invalidate pages
associated with the range of the file to be shifted.
xfs_free_file_space() currently has similar behavior, but the space free
need only affect the region of the file that is freed and this could
change in the future.

Also update the comments to reflect the current implementation. We
retain the eofblocks trim permanently as a best option for dealing with
delalloc extents. We don't shift delalloc extents because this scenario
only occurs with post-eof preallocation (since data must be flushed such
that the cache can be invalidated and data can be shifted). That means
said space must also be initialized before being shifted into the
accessible region of the file only to be immediately truncated off as
the last part of the collapse. In other words, the eofblocks trim will
happen anyways, we just run it first to ensure the file remains in a
consistent state throughout the collapse.

Finally, detect and fail explicitly in the event of a delalloc extent
during the extent shift. The implementation does not support delalloc
extents and the caller is expected to prevent this scenario in advance
as is done by collapse.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:39:05 +10:00
Brian Foster
a979bdfea1 xfs: refactor single extent shift into xfs_bmse_shift_one() helper
xfs_bmap_shift_extents() has a variety of conditions and error checks
that make the logic difficult to follow and indent heavy. Refactor the
loop body of this function into a new xfs_bmse_shift_one() helper. This
simplifies the error checks, eliminates index decrement on merge hack by
pushing the index increment down into the helper, and makes the code
more readable by reducing multiple levels of indentation.

This is a code refactor only. The behavior of extent shift and collapse
range is not modified.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:39:04 +10:00
Brian Foster
ddb19e3180 xfs: refactor shift-by-merge into xfs_bmse_merge() helper
The extent shift mechanism in xfs_bmap_shift_extents() is complicated
and handles several different, non-deterministic scenarios. These
include extent shifts, extent merges and potential btree updates in
either of the former scenarios.

Refactor the code to be more linear and readable. The loop logic in
xfs_bmap_shift_extents() and some initial error checking is adjusted
slightly. The associated btree lookup and update/delete operations are
condensed into single blocks of code. This reduces the number of
btree-specific blocks and facilitates the separation of the merge
operation into a new xfs_bmse_merge() and xfs_bmse_can_merge() helpers.

This is a code refactor only. The behavior of extent shift and collapse
range is not modified.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:38:09 +10:00
Brian Foster
2c845f5a5f xfs: track collapse via file offset rather than extent index
The collapse range implementation uses a transaction per extent shift.
The progress of the overall operation is tracked via the current extent
index of the in-core extent list. This is racy because the ilock must be
dropped and reacquired for each transaction according to locking and log
reservation rules. Therefore, writeback to prior regions of the file is
possible and can change the extent count. This changes the extent to
which the current index refers and causes the collapse to fail mid
operation. To avoid this problem, the entire file is currently written
back before the collapse operation starts.

To eliminate the need to flush the entire file, use the file offset
(fsb) to track the progress of the overall extent shift operation rather
than the extent index. Modify xfs_bmap_shift_extents() to
unconditionally convert the start_fsb parameter to an extent index and
return the file offset of the extent where the shift left off, if
further extents exist. The bulk of ths function can remain based on
extent index as ilock is held by the caller. xfs_collapse_file_space()
now uses the fsb output as the starting point for the subsequent shift.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:37:09 +10:00
Dave Chinner
0d085a529b xfs: ensure WB_SYNC_ALL writeback handles partial pages correctly
XFS has been having trouble with stray delayed allocation extents
beyond EOF for a long time. Recent changes to the collapse range
code has triggered erroneous EBUSY errors on page invalidtion for
block size smaller than page size filesystems. These
have been caused by dirty buffers beyond EOF on a partial page which
do not get written to disk during a sync.

The issue is that write-ahead in xfs_cluster_write() finds such a
partial page and handles it by leaving the page dirty but pushing it
into a writeback state. This used to work just fine, as the
write_cache_pages() code would then find the dirty partial page in
the next mapping tree lookup as the dirty tag is still set.

Unfortunately, when we moved to a mark and sweep approach to
writeback to fix other writeback sync issues, we broken this. THe
act of marking the page as under writeback now clears the TOWRITE
tag in the radix tree, even though the page is still dirty. This
causes the TOWRITE tag to be cleared, and hence the next lookup on
the mapping tree does not find the dirty partial page and so doesn't
try to write it again.

This same writeback bug was found recently in ext4 and fixed in
commit 1c8349a ("ext4: fix data integrity sync in ordered mode")
without communication to the wider filesystem community. We can use
exactly the same fix here so the TOWRITE flag is not cleared on
partial page writes.

cc: stable@vger.kernel.org # dependent on 1c8349a171
Root-cause-found-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-23 15:36:27 +10:00
Jens Axboe
6d11fb454b Merge branch 'for-linus' into for-3.18/core
Moving patches from for-linus to 3.18 instead, pull in this changes
that will go to Linus today.
2014-09-22 11:57:32 -06:00
Dave Chinner
a4241aebe9 Merge branch 'xfs-misc-fixes-for-3.18-1' into for-next 2014-09-09 13:25:31 +10:00
Eric Sandeen
ab6978c295 xfs: remove rbpp check from xfs_rtmodify_summary_int
rbpp is always passed into xfs_rtmodify_summary
and xfs_rtget_summary, so there is no need to
test for it in xfs_rtmodify_summary_int.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:59:12 +10:00
Eric Sandeen
afabfd30d0 xfs: combine xfs_rtmodify_summary and xfs_rtget_summary
xfs_rtmodify_summary and xfs_rtget_summary are almost identical;
fold them into xfs_rtmodify_summary_int(), with wrappers for each of
the original calls.

The _int function modifies if a delta is passed, and returns a
summary pointer if *sum is passed.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:58:42 +10:00
Eric Sandeen
b16ed7c114 xfs: combine xfs_dir_canenter into xfs_dir_createname
xfs_dir_canenter and xfs_dir_createname are
almost identical.

Fold the former into the latter, with a helpful
wrapper for the former.  If createname is called without
an inode number, it now only checks for space, and does
not actually add the entry.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:58:07 +10:00
Eric Sandeen
94f3cad555 xfs: check resblks before calling xfs_dir_canenter
Move the resblks test out of the xfs_dir_canenter,
and into the caller.

This makes a little more sense on the face of it;
xfs_dir_canenter immediately returns if resblks !=0;
and given some of the comments preceding the calls:

 * Check for ability to enter directory entry, if no space reserved.

even more so.

It also facilitates the next patch.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:57:52 +10:00
Eric Sandeen
970fd3f04d xfs: deduplicate xlog_do_recovery_pass()
In xlog_do_recovery_pass(), there are 2 distinct cases:
non-wrapped and wrapped log recovery.

If we find a wrapped log, we recover around the end
of the log, and then handle the rest of recovery
exactly as in the non-wrapped case - using exactly the same
(duplicated) code.

Rather than having the same code in both cases, we can
get the wrapped portion out of the way first if needed,
and then recover the non-wrapped portion of the log.

There should be no functional change here, just code
reorganization & deduplication.

The patch looks a bit bigger than it really is; the last
hunk is whitespace changes (un-indenting).

Tested with xfstests "check -g log" on a stock configuration.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:57:29 +10:00
Eric Sandeen
59f9c00432 xfs: lseek: the "whence" argument is called "whence"
For some reason, the older commit:

    965c8e5 lseek: the "whence" argument is called "whence"

    lseek: the "whence" argument is called "whence"

    But the kernel decided to call it "origin" instead.
    Fix most of the sites.

left out xfs.  So fix xfs.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:57:10 +10:00
Eric Sandeen
49c69591c8 xfs: combine xfs_seek_hole & xfs_seek_data
xfs_seek_hole & xfs_seek_data are remarkably similar;
so much so that they can be combined, saving a fair
bit of semi-complex code duplication.

The following patch passes generic/285 and generic/286,
which specifically test seek behavior.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:56:48 +10:00
Brian Foster
2e22717874 xfs: export log_recovery_delay to delay mount time log recovery
XFS log recovery has been discovered to have race conditions with
buffers when I/O errors occur. External tools are available to simulate
I/O errors to XFS, but this alone is not sufficient for testing log
recovery. XFS unconditionally resets the inactive region of the log
prior to log recovery to avoid confusion over processing any partially
written log records that might have been written before an unclean
shutdown. Therefore, unconditional write I/O failures at mount time are
caught by the reset sequence rather than log recovery and hinder the
ability to test the latter.

The device-mapper dm-flakey module uses an up/down timer to define a
cycle for when to fail I/Os. Create a pre log recovery delay tunable
that can be used to coordinate XFS log recovery with I/O errors
simulated by dm-flakey. This facilitates coordination in userspace that
allows the reset of stale log blocks to succeed and writes due to log
recovery to fail. For example, define a dm-flakey instance with an
uptime long enough to allow log reset to succeed and a log recovery
delay long enough to allow the dm-flakey uptime to expire.

The 'log_recovery_delay' sysfs tunable is exported under
/sys/fs/xfs/debug and is only enabled for kernels compiled in XFS debug
mode. The value is exported in units of seconds and allows for a delay
of up to 60 seconds. Note that this is for XFS debug and test
instrumentation purposes only and should not be used by applications. No
delay is enabled by default.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:56:13 +10:00
Brian Foster
65b65735fe xfs: add debug sysfs attribute set
Create a top-level debug directory for global debug sysfs attributes.
This directory is added and removed on XFS module initialization and
removal respectively for DEBUG mode kernels only. It typically resides
at /sys/fs/xfs/debug. It is located at the top level of the xfs sysfs
hierarchy as attributes might define global behavior or behavior that
must be configured before an xfs mount is available (e.g., log recovery
behavior).

Define the global debug kobject that represents the debug sysfs
directory and add generic attribute show/store helpers to support future
attributes. No debug attributes are exported as of yet.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:52:42 +10:00
Eric Sandeen
e1b05723ed xfs: add a few more verifier tests
These were exposed by fsfuzzer runs; without them we fail
in various exciting and sometimes convoluted ways when we
encounter disk corruption.

Without the MAXLEVELS tests we tend to walk off the end of
an array in a loop like this:

        for (i = 0; i < cur->bc_nlevels; i++) {
                if (cur->bc_bufs[i])

Without the dirblklog test we try to allocate more memory
than we could possibly hope for and loop forever:

xfs_dabuf_map()
	nfsb = mp->m_dir_geo->fsbcount;
	irecs = kmem_zalloc(sizeof(irec) * nfsb, KM_SLEEP...

As for the logbsize check, that's the convoluted one.

If logbsize is specified at mount time, it's sanitized
in xfs_parseargs; in particular it makes sure that it's
not > XLOG_MAX_RECORD_BSIZE.

If not specified at mount time, it comes from the superblock
via sb_logsunit; this is limited to 256k at mkfs time as well;
it's copied into m_logbsize in xfs_finish_flags().

However, if for some reason the on-disk value is corrupt and
too large, nothing catches it.  It's a circuitous path, but
that size eventually finds its way to places that make the kernel
very unhappy, leading to oopses in xlog_pack_data() because we
use the size as an index into iclog->ic_data, but the array
is not necessarily that big.

Anyway - bounds checking when we read from disk is a good thing!

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:47:24 +10:00
Brian Foster
8018ec083c xfs: mark all internal workqueues as freezable
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 <bfoster@redhat.com>
Reported-by: Carlos E. R. <carlos.e.r@opensuse.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-09 11:44:46 +10:00
Tejun Heo
ff9ea32381 block, bdi: an active gendisk always has a request_queue associated with it
bdev_get_queue() returns the request_queue associated with the
specified block_device.  blk_get_backing_dev_info() makes use of
bdev_get_queue() to determine the associated bdi given a block_device.

All the callers of bdev_get_queue() including
blk_get_backing_dev_info() assume that bdev_get_queue() may return
NULL and implement NULL handling; however, bdev_get_queue() requires
the passed in block_device is opened and attached to its gendisk.
Because an active gendisk always has a valid request_queue associated
with it, bdev_get_queue() can never return NULL and neither can
blk_get_backing_dev_info().

Make it clear that neither of the two functions can return NULL and
remove NULL handling from all the callers.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Mason <clm@fb.com>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2014-09-08 10:00:35 -06:00
Brian Foster
41b9d7263e xfs: trim eofblocks before collapse range
xfs_collapse_file_space() currently writes back the entire file
undergoing collapse range to settle things down for the extent shift
algorithm. While this prevents changes to the extent list during the
collapse operation, the writeback itself is not enough to prevent
unnecessary collapse failures.

The current shift algorithm uses the extent index to iterate the in-core
extent list. If a post-eof delalloc extent persists after the writeback
(e.g., a prior zero range op where the end of the range aligns with eof
can separate the post-eof blocks such that they are not written back and
converted), xfs_bmap_shift_extents() becomes confused over the encoded
br_startblock value and fails the collapse.

As with the full writeback, this is a temporary fix until the algorithm
is improved to cope with a volatile extent list and avoid attempts to
shift post-eof extents.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:53 +10:00
Dave Chinner
1669a8ca21 xfs: xfs_file_collapse_range is delalloc challenged
If we have delalloc extents on a file before we run a collapse range
opertaion, we sync the range that we are going to collapse to
convert delalloc extents in that region to real extents to simplify
the shift operation.

However, the shift operation then assumes that the extent list is
not going to change as it iterates over the extent list moving
things about. Unfortunately, this isn't true because we can't hold
the ILOCK over all the operations. We can prevent new IO from
modifying the extent list by holding the IOLOCK, but that doesn't
prevent writeback from running....

And when writeback runs, it can convert delalloc extents is the
range of the file prior to the region being collapsed, and this
changes the indexes of all the extents in the file. That causes the
collapse range operation to Go Bad.

The right fix is to rewrite the extent shift operation not to be
dependent on the extent list not changing across the entire
operation, but this is a fairly significant piece of work to do.
Hence, as a short-term workaround for the problem, sync the entire
file before starting a collapse operation to remove all delalloc
ranges from the file and so avoid the problem of concurrent
writeback changing the extent list.

Diagnosed-and-Reported-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:53 +10:00
Brian Foster
ca446d880c xfs: don't log inode unless extent shift makes extent modifications
The file collapse mechanism uses xfs_bmap_shift_extents() to collapse
all subsequent extents down into the specified, previously punched out,
region. This function performs some validation, such as whether a
sufficient hole exists in the target region of the collapse, then shifts
the remaining exents downward.

The exit path of the function currently logs the inode unconditionally.
While we must log the inode (and abort) if an error occurs and the
transaction is dirty, the initial validation paths can generate errors
before the transaction has been dirtied. This creates an unnecessary
filesystem shutdown scenario, as the caller will cancel a transaction
that has been marked dirty.

Modify xfs_bmap_shift_extents() to OR the logflags bits as modifications
are made to the inode bmap. Only log the inode in the exit path if
logflags has been set. This ensures we only have to cancel a dirty
transaction if modifications have been made and prevents an unnecessary
filesystem shutdown otherwise.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:53 +10:00
Dave Chinner
7d4ea3ce63 xfs: use ranged writeback and invalidation for direct IO
Now we are not doing silly things with dirtying buffers beyond EOF
and using invalidation correctly, we can finally reduce the ranges of
writeback and invalidation used by direct IO to match that of the IO
being issued.

Bring the writeback and invalidation ranges back to match the
generic direct IO code - this will greatly reduce the perturbation
of cached data when direct IO and buffered IO are mixed, but still
provide the same buffered vs direct IO coherency behaviour we
currently have.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:53 +10:00
Dave Chinner
834ffca6f7 xfs: don't zero partial page cache pages during O_DIRECT writes
Similar to direct IO reads, direct IO writes are using 
truncate_pagecache_range to invalidate the page cache. This is
incorrect due to the sub-block zeroing in the page cache that
truncate_pagecache_range() triggers.

This patch fixes things by using invalidate_inode_pages2_range
instead.  It preserves the page cache invalidation, but won't zero
any pages.

cc: stable@vger.kernel.org
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:52 +10:00
Chris Mason
85e584da32 xfs: don't zero partial page cache pages during O_DIRECT writes
xfs is using truncate_pagecache_range to invalidate the page cache
during DIO reads.  This is different from the other filesystems who
only invalidate pages during DIO writes.

truncate_pagecache_range is meant to be used when we are freeing the
underlying data structs from disk, so it will zero any partial
ranges in the page.  This means a DIO read can zero out part of the
page cache page, and it is possible the page will stay in cache.

buffered reads will find an up to date page with zeros instead of
the data actually on disk.

This patch fixes things by using invalidate_inode_pages2_range
instead.  It preserves the page cache invalidation, but won't zero
any pages.

[dchinner: catch error and warn if it fails. Comment.]

cc: stable@vger.kernel.org
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:52 +10:00
Dave Chinner
22e757a49c xfs: don't dirty buffers beyond EOF
generic/263 is failing fsx at this point with a page spanning
EOF that cannot be invalidated. The operations are:

1190 mapwrite   0x52c00 thru    0x5e569 (0xb96a bytes)
1191 mapread    0x5c000 thru    0x5d636 (0x1637 bytes)
1192 write      0x5b600 thru    0x771ff (0x1bc00 bytes)

where 1190 extents EOF from 0x54000 to 0x5e569. When the direct IO
write attempts to invalidate the cached page over this range, it
fails with -EBUSY and so any attempt to do page invalidation fails.

The real question is this: Why can't that page be invalidated after
it has been written to disk and cleaned?

Well, there's data on the first two buffers in the page (1k block
size, 4k page), but the third buffer on the page (i.e. beyond EOF)
is failing drop_buffers because it's bh->b_state == 0x3, which is
BH_Uptodate | BH_Dirty.  IOWs, there's dirty buffers beyond EOF. Say
what?

OK, set_buffer_dirty() is called on all buffers from
__set_page_buffers_dirty(), regardless of whether the buffer is
beyond EOF or not, which means that when we get to ->writepage,
we have buffers marked dirty beyond EOF that we need to clean.
So, we need to implement our own .set_page_dirty method that
doesn't dirty buffers beyond EOF.

This is messy because the buffer code is not meant to be shared
and it has interesting locking issues on the buffer dirty bits.
So just copy and paste it and then modify it to suit what we need.

Note: the solutions the other filesystems and generic block code use
of marking the buffers clean in ->writepage does not work for XFS.
It still leaves dirty buffers beyond EOF and invalidations still
fail. Hence rather than play whack-a-mole, this patch simply
prevents those buffers from being dirtied in the first place.

cc: <stable@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-09-02 12:12:51 +10:00
Dave Chinner
645f985721 Merge branch 'xfs-misc-fixes-3.17-2' into for-next 2014-08-04 13:55:27 +10:00
Dave Chinner
b076d8720d Merge branch 'xfs-bulkstat-refactor' into for-next 2014-08-04 13:54:46 +10:00
Dave Chinner
4d7eece2c0 Merge branch 'xfs-misc-fixes-3.17-1' into for-next 2014-08-04 13:54:14 +10:00
Dave Chinner
e0ac6d45bc Merge branch 'xfs-quota-eofblocks-scan' into for-next 2014-08-04 13:53:47 +10:00
kbuild test robot
6eee8972cc xfs: fix coccinelle warnings
Removes unneeded semicolon, introduced by commit a70a4fa5 ("xfs: fix
a couple error sequence jumps in xfs_mountfs"):

fs/xfs/xfs_mount.c:858:24-25: Unneeded semicolon

Generated by: scripts/coccinelle/misc/semicolon.cocci

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:49:40 +10:00
Dave Chinner
4ef897a275 xfs: flush both inodes in xfs_swap_extents
We need to treat both inodes identically from a page cache point of
view when prepareing them for extent swapping. We don't do this
right now - we assume that one of the inodes empty, because that's
what xfs_fsr currently does. Remove this assumption from the code.

While factoring out the flushing and related checks, move the
transactions reservation to immeidately after the flushes so that we
don't need to pick up and then drop the ilock to do the transaction
reservation. There are no issues with aborting the transaction it if
the checks fail before we join the inodes to the transaction and
dirty them, so this is a safe change to make.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:44:08 +10:00
Dave Chinner
8121768321 xfs: fix swapext ilock deadlock
xfs_swap_extents() holds the ilock over a call to
filemap_write_and_wait(), which can then try to write data and take
the ilock. That causes a self-deadlock.

Fix the deadlock and clean up the code by separating the locking
appropriately. Add a lockflags variable to track what locks we are
holding as we gain and drop them and cleanup the error handling to
always use "out_unlock" with the lockflags variable.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:29:32 +10:00
Dave Chinner
b92cc59f69 xfs: kill xfs_vnode.h
Move the IO flag definitions to xfs_inode.h and kill the header file
as it is now empty.

Removing the xfs_vnode.h file showed up an implicit header include
path:
	xfs_linux.h -> xfs_vnode.h -> xfs_fs.h

And so every xfs header file has been inplicitly been including
xfs_fs.h where it is needed or not. Hence the removal of xfs_vnode.h
causes all sorts of build issues because BBTOB() and friends are no
longer automatically included in the build. This also gets fixed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:28:20 +10:00
Dave Chinner
dd8c38bab0 xfs: kill VN_MAPPED
Only one user, no longer needed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:23:35 +10:00
Dave Chinner
2667c6f935 xfs: kill VN_CACHED
Only has 2 users, has outlived it's usefulness.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:23:15 +10:00
Dave Chinner
eac152b474 xfs: kill VN_DIRTY()
Only one user of the macro and the dirty mapping check is redundant
so just get rid of it.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 13:22:49 +10:00
Dave Chinner
ad3714b82c xfs: dquot recovery needs verifiers
dquot recovery should add verifiers to the dquot buffers that it
recovers changes into. Unfortunately, it doesn't attached the
verifiers to the buffers in a consistent manner. For example,
xlog_recover_dquot_pass2() reads dquot buffers without a verifier
and then writes it without ever having attached a verifier to the
buffer.

Further, dquot buffer recovery may write a dquot buffer that has not
been modified, or indeed, shoul dbe written because quotas are not
enabled and hence changes to the buffer were not replayed. In this
case, we again write buffers without verifiers attached because that
doesn't happen until after the buffer changes have been replayed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 12:59:31 +10:00
Dave Chinner
5fd364fee8 xfs: quotacheck leaves dquot buffers without verifiers
When running xfs/305, I noticed that quotacheck was flushing dquot
buffers that did not have the xfs_dquot_buf_ops verifiers attached:

XFS (vdb): _xfs_buf_ioapply: no ops on block 0x1dc8/0x1dc8
ffff880052489000: 44 51 01 04 00 00 65 b8 00 00 00 00 00 00 00 00  DQ....e.........
ffff880052489010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
ffff880052489020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
ffff880052489030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
CPU: 1 PID: 2376 Comm: mount Not tainted 3.16.0-rc2-dgc+ #306
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
 ffff88006fe38000 ffff88004a0ffae8 ffffffff81cf1cca 0000000000000001
 ffff88004a0ffb88 ffffffff814d50ca 000010004a0ffc70 0000000000000000
 ffff88006be56dc4 0000000000000021 0000000000001dc8 ffff88007c773d80
Call Trace:
 [<ffffffff81cf1cca>] dump_stack+0x45/0x56
 [<ffffffff814d50ca>] _xfs_buf_ioapply+0x3ca/0x3d0
 [<ffffffff810db520>] ? wake_up_state+0x20/0x20
 [<ffffffff814d51f5>] ? xfs_bdstrat_cb+0x55/0xb0
 [<ffffffff814d513b>] xfs_buf_iorequest+0x6b/0xd0
 [<ffffffff814d51f5>] xfs_bdstrat_cb+0x55/0xb0
 [<ffffffff814d53ab>] __xfs_buf_delwri_submit+0x15b/0x220
 [<ffffffff814d6040>] ? xfs_buf_delwri_submit+0x30/0x90
 [<ffffffff814d6040>] xfs_buf_delwri_submit+0x30/0x90
 [<ffffffff8150f89d>] xfs_qm_quotacheck+0x17d/0x3c0
 [<ffffffff81510591>] xfs_qm_mount_quotas+0x151/0x1e0
 [<ffffffff814ed01c>] xfs_mountfs+0x56c/0x7d0
 [<ffffffff814f0f12>] xfs_fs_fill_super+0x2c2/0x340
 [<ffffffff811c9fe4>] mount_bdev+0x194/0x1d0
 [<ffffffff814f0c50>] ? xfs_finish_flags+0x170/0x170
 [<ffffffff814ef0f5>] xfs_fs_mount+0x15/0x20
 [<ffffffff811ca8c9>] mount_fs+0x39/0x1b0
 [<ffffffff811e4d67>] vfs_kern_mount+0x67/0x120
 [<ffffffff811e757e>] do_mount+0x23e/0xad0
 [<ffffffff8117abde>] ? __get_free_pages+0xe/0x50
 [<ffffffff811e71e6>] ? copy_mount_options+0x36/0x150
 [<ffffffff811e8103>] SyS_mount+0x83/0xc0
 [<ffffffff81cfd40b>] tracesys+0xdd/0xe2

This was caused by dquot buffer readahead not attaching a verifier
structure to the buffer when readahead was issued, resulting in the
followup read of the buffer finding a valid buffer and so not
attaching new verifiers to the buffer as part of the read.

Also, when a verifier failure occurs, we then read the buffer
without verifiers. Attach the verifiers manually after this read so
that if the buffer is then written it will be verified that the
corruption has been repaired.

Further, when flushing a dquot we don't ask for a verifier when
reading in the dquot buffer the dquot belongs to. Most of the time
this isn't an issue because the buffer is still cached, but when it
is not cached it will result in writing the dquot buffer without
having the verfier attached.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 12:43:26 +10:00
Dave Chinner
67dc288c21 xfs: ensure verifiers are attached to recovered buffers
Crash testing of CRC enabled filesystems has resulted in a number of
reports of bad CRCs being detected after the filesystem was mounted.
Errors such as the following were being seen:

XFS (sdb3): Mounting V5 Filesystem
XFS (sdb3): Starting recovery (logdev: internal)
XFS (sdb3): Metadata CRC error detected at xfs_agf_read_verify+0x5a/0x100 [xfs], block 0x1
XFS (sdb3): Unmount and run xfs_repair
XFS (sdb3): First 64 bytes of corrupted metadata buffer:
ffff880136ffd600: 58 41 47 46 00 00 00 01 00 00 00 00 00 0f aa 40  XAGF...........@
ffff880136ffd610: 00 02 6d 53 00 02 77 f8 00 00 00 00 00 00 00 01  ..mS..w.........
ffff880136ffd620: 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00 03  ................
ffff880136ffd630: 00 00 00 04 00 08 81 d0 00 08 81 a7 00 00 00 00  ................
XFS (sdb3): metadata I/O error: block 0x1 ("xfs_trans_read_buf_map") error 74 numblks 1

The errors were typically being seen in AGF, AGI and their related
btree block buffers some time after log recovery had run. Often it
wasn't until later subsequent mounts that the problem was
discovered. The common symptom was a buffer with the correct
contents, but a CRC and an LSN that matched an older version of the
contents.

Some debug added to _xfs_buf_ioapply() indicated that buffers were
being written without verifiers attached to them from log recovery,
and Jan Kara isolated the cause to log recovery readahead an dit's
interactions with buffers that had a more recent LSN on disk than
the transaction being recovered. In this case, the buffer did not
get a verifier attached, and os when the second phase of log
recovery ran and recovered EFIs and unlinked inodes, the buffers
were modified and written without the verifier running. Hence they
had up to date contents, but stale LSNs and CRCs.

Fix it by attaching verifiers to buffers we skip due to future LSN
values so they don't escape into the buffer cache without the
correct verifier attached.

This patch is based on analysis and a patch from Jan Kara.

cc: <stable@vger.kernel.org>
Reported-by: Jan Kara <jack@suse.cz>
Reported-by: Fanael Linithien <fanael4@gmail.com>
Reported-by: Grozdan <neutrino8@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 12:43:06 +10:00
Dave Chinner
400b9d8875 xfs: catch buffers written without verifiers attached
We recently had a bug where buffers were slipping through log
recovery without any verifier attached to them. This was resulting
in on-disk CRC mismatches for valid data. Add some warning code to
catch this occurrence so that we catch such bugs during development
rather than not being aware they exist.

Note that we cannot do this verification unconditionally as non-CRC
filesystems don't always attach verifiers to the buffers being
written. e.g. during log recovery we cannot identify all the
different types of buffers correctly on non-CRC filesystems, so we
can't attach the correct verifiers in all cases and so we don't
attach any. Hence we don't want on non-CRC filesystems to avoid
spamming the logs with false indications.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 12:42:40 +10:00
Eric Sandeen
5ef828c415 xfs: avoid false quotacheck after unclean shutdown
The commit

83e782e xfs: Remove incore use of XFS_OQUOTA_ENFD and XFS_OQUOTA_CHKD

added a new function xfs_sb_quota_from_disk() which swaps
on-disk XFS_OQUOTA_* flags for in-core XFS_GQUOTA_* and XFS_PQUOTA_*
flags after the superblock is read.

However, if log recovery is required, the superblock is read again,
and the modified in-core flags are re-read from disk, so we have
XFS_OQUOTA_* flags in memory again.  This causes the
XFS_QM_NEED_QUOTACHECK() test to be true, because the XFS_OQUOTA_CHKD
is still set, and not XFS_GQUOTA_CHKD or XFS_PQUOTA_CHKD.

Change xfs_sb_from_disk to call xfs_sb_quota_from disk and always
convert the disk flags to in-memory flags.

Add a lower-level function which can be called with "false" to
not convert the flags, so that the sb verifier can verify
exactly what was on disk, per Brian Foster's suggestion.

Reported-by: Cyril B. <cbay@excellency.fr>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
2014-08-04 11:35:44 +10:00
Brian Foster
eedf32bfca xfs: fix rounding error of fiemap length parameter
The offset and length parameters are converted from bytes to basic
blocks by xfs_vn_fiemap(). The BTOBB() converter rounds the value up to
the nearest basic block. This leads to unexpected behavior when
unaligned offsets are provided to FIEMAP.

Fix the conversions of byte values to block values to cover the provided
offsets. Round down the start offset to the nearest basic block.
Calculate the end offset based on the provided values, round up and
calculate length based on the start block offset.

Reported-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 11:35:35 +10:00
Jie Liu
1e773c4989 xfs: introduce xfs_bulkstat_ag_ichunk
Introduce xfs_bulkstat_ag_ichunk() to process inodes in chunk with a
pointer to a formatter function that will iget the inode and fill in
the appropriate structure.

Refactor xfs_bulkstat() with it.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-08-04 11:22:31 +10:00
Christoph Hellwig
d5cf09bace xfs: require 64-bit sector_t
Trying to support tiny disks only and saving a bit memory might have
made sense on an SGI O2 15 years ago, but is pretty pointless today.

Remove the rarely tested codepath that uses various smaller in-memory
types to reduce our test matrix and make the codebase a little bit
smaller and less complicated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-30 09:12:05 +10:00
Jie Liu
74dc93a908 xfs: fix uflags detection at xfs_fs_rm_xquota
We are intended to check up uflags against FS_PROJ_QUOTA rather than
FS_USER_UQUOTA once more, it looks to me like a typo, but might cause
the project quota metadata space can not be removed.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 21:27:17 +10:00
Jie Liu
7b409a7d6f xfs: remove XFS_IS_OQUOTA_ON macros
Remove the XFS_IS_OQUOTA_ON macros as it is obsoleted.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 21:27:16 +10:00
Eric Sandeen
54aa61f82d xfs: tidy up xfs_set_inode32
xfs_set_inode32() caught my eye because it had weird spacing around
the "-1's".  In cleaning that up, I realized that the assignment in
the declaration of "ino" is never used; it's rewritten before it
gets read.

Drop the ino initializer from its declaration since it's not used,
and move the agino initialization into the body of the function,
mostly so that we can have pretty whitespace and not exceed 80
columns.  :)

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 20:53:10 +10:00
Eric Sandeen
9de67c3ba9 xfs: allow inode allocations in post-growfs disk space
Today, if we perform an xfs_growfs which adds allocation groups,
mp->m_maxagi is not properly updated when the growfs is complete.

Therefore inodes will continue to be allocated only in the
AGs which existed prior to the growfs, and the new space
won't be utilized.

This is because of this path in xfs_growfs_data_private():

xfs_growfs_data_private
	xfs_initialize_perag(mp, nagcount, &nagimax);
		if (mp->m_flags & XFS_MOUNT_32BITINODES)
			index = xfs_set_inode32(mp);
		else
			index = xfs_set_inode64(mp);

		if (maxagi)
			*maxagi = index;

where xfs_set_inode* iterates over the (old) agcount in
mp->m_sb.sb_agblocks, which has not yet been updated
in the growfs path.  So "index" will be returned based on
the old agcount, not the new one, and new AGs are not available
for inode allocation.

Fix this by explicitly passing the proper AG count (which
xfs_initialize_perag() already has) down another level,
so that xfs_set_inode* can make the proper decision about
acceptable AGs for inode allocation in the potentially
newly-added AGs.

This has been broken since 3.7, when these two
xfs_set_inode* functions were added in commit 2d2194f.
Prior to that, we looped over "agcount" not sb_agblocks
in these calculations.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 20:51:54 +10:00
Jie Liu
eb866bbf09 xfs: mark xfs_qm_quotacheck as static
xfs_qm_quotacheck() is not used outside of xfs_qm.c.  Mark it static
and move it around in the file to avoid a forward declaration.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 20:49:57 +10:00
Mark Tinguely
5c18717ea2 xfs: fix cil push sequence after log recovery
When the CIL checkpoint is fully written to the log, the LSN of the checkpoint
commit record is written into the CIL context structure. This allows log force
waiters to correctly detect when the checkpoint they are waiting on have been
fully written into the log buffers.

However, the initial context after mount is initialised with a non-zero commit
LSN, so appears to waiters as though it is complete even though it may not have
even been pushed, let alone written to the log buffers. Hence a log force
immediately after a filesystem is mounted may not behave correctly, nor does
commit record ordering if multiple CIL pushes interleave immediately after
mount.

To fix this, make sure the initial context commit LSN is not touched until the
first checkpointis actually pushed.

[dchinner: rewrite commit message]

Signed-off-by: Mark Tinguely <tinguely@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 20:49:40 +10:00
Brian Foster
f074051ff5 xfs: squash prealloc while over quota free space as well
From: Brian Foster <bfoster@redhat.com>

Commit 4d559a3b introduced heavy prealloc. squashing to catch the case
of requesting too large a prealloc on smaller filesystems, leading to
repeated flush and retry cycles that occur on ENOSPC. Now that we issue
eofblocks scans on EDQUOT/ENOSPC, squash the prealloc against the
minimum available free space across all applicable quotas as well to
avoid a similar problem of repeated eofblocks scans.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 19:56:08 +10:00
Brian Foster
dc06f398f0 xfs: run an eofblocks scan on ENOSPC/EDQUOT
From: Brian Foster <bfoster@redhat.com>

Speculative preallocation and and the associated throttling metrics
assume we're working with large files on large filesystems. Users have
reported inefficiencies in these mechanisms when we happen to be dealing
with large files on smaller filesystems. This can occur because while
prealloc throttling is aggressive under low free space conditions, it is
not active until we reach 5% free space or less.

For example, a 40GB filesystem has enough space for several files large
enough to have multi-GB preallocations at any given time. If those files
are slow growing, they might reserve preallocation for long periods of
time as well as avoid the background scanner due to frequent
modification. If a new file is written under these conditions, said file
has no access to this already reserved space and premature ENOSPC is
imminent.

To handle this scenario, modify the buffered write ENOSPC handling and
retry sequence to invoke an eofblocks scan. In the smaller filesystem
scenario, the eofblocks scan resets the usage of preallocation such that
when the 5% free space threshold is met, throttling effectively takes
over to provide fair and efficient preallocation until legitimate
ENOSPC.

The eofblocks scan is selective based on the nature of the failure. For
example, an EDQUOT failure in a particular quota will use a filtered
scan for that quota. Because we don't know which quota might have caused
an allocation failure at any given time, we include each applicable
quota determined to be under low free space conditions in the scan.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 19:49:28 +10:00
Brian Foster
f452639792 xfs: support a union-based filter for eofblocks scans
From: Brian Foster <bfoster@redhat.com>

The eofblocks scan inode filter uses intersection logic by default.
E.g., specifying both user and group quota ids filters out inodes that
are not covered by both the specified user and group quotas. This is
suitable for behavior exposed to userspace.

Scans that are initiated from within the kernel might require more broad
semantics, such as scanning all inodes under each quota associated with
an inode to alleviate low free space conditions in each.

Create the XFS_EOF_FLAGS_UNION flag to support a conditional union-based
filtering algorithm for eofblocks scans. This flag is intentionally left
out of the valid mask as it is not supported for scans initiated from
userspace.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 19:44:28 +10:00
Brian Foster
5400da7dc0 xfs: add scan owner field to xfs_eofblocks
From: Brian Foster <bfoster@redhat.com>

The scan owner field represents an optional inode number that is
responsible for the current scan. The purpose is to identify that an
inode is under iolock and as such, the iolock shouldn't be attempted
when trimming eofblocks. This is an internal only field.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 19:40:22 +10:00
Jie Liu
f3d1e58743 xfs: introduce xfs_bulkstat_grab_ichunk
From: Jie Liu <jeff.liu@oracle.com>

Introduce xfs_bulkstat_grab_ichunk() to look up an inode chunk in where
the given inode resides, then grab the record.  Update the data for the
pointed-to record if the inode was not the last in the chunk and there
are some left allocated, return the grabbed inode count on success.

Refactor xfs_bulkstat() with it.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 18:42:21 +10:00
Jie Liu
4b8fdfecd8 xfs: introduce xfs_bulkstat_ichunk_ra
From: Jie Liu <jeff.liu@oracle.com>

Introduce xfs_bulkstat_ichunk_ra() to loop over all clusters in the
next inode chunk, then performs readahead if there are any allocated
inodes in that cluster.

Refactor xfs_bulkstat() with it.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 18:41:18 +10:00
Jie Liu
d4c2734875 xfs: fix error handling at xfs_bulkstat
From: Jie Liu <jeff.liu@oracle.com>

We should not ignore the btree operation errors at xfs_bulkstat() but
to propagate them if any. This patch fix two places in this function
and the remaining things will be fixed with code refactoring thereafter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 18:40:43 +10:00
Jie Liu
296dfd7fdb xfs: remove redundant user buffer count checks at xfs_bulkstat
From: Jie Liu <jeff.liu@oracle.com>

Remove the redundant user buffer and count checks as it has already
been validated at xfs_ioc_bulkstat().

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 18:40:26 +10:00
Jie Liu
c7cb51dcb0 xfs: fix error handling at xfs_inumbers
From: Jie Liu <jeff.liu@oracle.com>

To fetch the file system number tables, we currently just ignore the
errors and proceed to loop over the next AG or bump agino to the next
chunk in case of btree operations failed, that is not properly because
those errors might hint us potential file system problems.

This patch rework xfs_inumbers() to handle the btree operation errors
as well as the loop conditions.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 12:18:47 +10:00
Jie Liu
549fa00679 xfs: consolidate xfs_inumbers
From: Jie Liu <jeff.liu@oracle.com>

Consolidate xfs_inumbers() to make the formatter function return correct
error and make the source code looks a bit neat.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 12:11:47 +10:00
Christoph Hellwig
d716f8eedb xfs: remove xfs_bulkstat_single
From: Christoph Hellwig <hch@lst.de>

xfs_bukstat_one doesn't have any failure case that would go away when
called through xfs_bulkstat, so remove the fallback and the now unessecary
xfs_bulkstat_single function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 12:07:15 +10:00
Jie Liu
8fe657760d xfs: remove redundant stat assignment in xfs_bulkstat_one_int
From: Jie Liu <jeff.liu@oracle.com>

Remove the redundant BULKSTAT_RV_NOTHING assignment in case of call
xfs_iget() failed at xfs_bulkstat_one_int().

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-24 11:33:28 +10:00
Brian Foster
80d6d69821 xfs: add log attributes for log lsn and grant head data
Create log attributes to export the current runtime state of the log to
sysfs. Note that the filesystem should be frozen for consistency across
attributes.

The following per-mount attributes are created: log_head_lsn,
log_tail_lsn, reserve_grant_head and write_grant_head. These represent
the physical log head, tail and reserve and write grant heads
respectively. Attribute values are exported in the following format:

	"cycle:[block,byte]"

... where cycle represents the log cycle and [block,bytes] represents
either the basic block or byte offset of the log, depending on the
attribute.  Log sequence number (LSN) values are encoded in basic blocks
and grant heads are encoded in bytes. All values are in decimal format.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 08:07:48 +10:00
Brian Foster
baff4e44b9 xfs: add xlog sysfs kobject and attribute handlers
Embed a kobject into the xfs log data structure (xlog). This creates a
'log' subdirectory for every XFS mount instance in sysfs. The lifecycle
of the log kobject is tied to the lifecycle of the log.

Also define a set of generic attribute handlers associated with the log
kobject in preparation for the addition of attributes.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 08:07:29 +10:00
Brian Foster
a31b1d3d89 xfs: add xfs_mount sysfs kobject
Embed a base kobject into xfs_mount. This creates a kobject associated
with each XFS mount and a subdirectory in sysfs with the name of the
filesystem. The subdirectory lifecycle matches that of the mount. Also
add the new xfs_sysfs.[c,h] source files with some XFS sysfs
infrastructure to facilitate attribute creation.

Note that there are currently no attributes exported as part of the
xfs_mount kobject. It exists solely to serve as a per-mount container
for child objects.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 08:07:01 +10:00
Brian Foster
3d8712265c xfs: add a sysfs kset
Create a sysfs kset to contain all sub-objects associated with the XFS
module. The kset is created and removed on module initialization and
removal respectively. The kset uses fs_obj as a parent. This leads to
the creation of a /sys/fs/xfs directory when the kset exists.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 07:41:37 +10:00
Brian Foster
a70a4fa528 xfs: fix a couple error sequence jumps in xfs_mountfs()
xfs_mountfs() has a couple failure conditions that do not jump to the
correct labels. Specifically:

- xfs_initialize_perag_data() failure does not deallocate the log even
  though it occurs after log initialization
- xfs_mount_reset_sbqflags() failure returns the error directly rather
  than jump to the error sequence

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 07:41:25 +10:00
Dave Chinner
7f8a058f6d Merge branch 'xfs-libxfs-restructure' into for-next 2014-07-15 07:37:18 +10:00
Dave Chinner
03e01349c6 xfs: null unused quota inodes when quota is on
When quota is on, it is expected that unused quota inodes have a
value of NULLFSINO. The changes to support a separate project quota
in 3.12 broken this rule for non-project quota inode enabled
filesystem, as the code now refuses to write the group quota inode
if neither group or project quotas are enabled. This regression was
introduced by commit d892d58 ("xfs: Start using pquotaino from the
superblock").

In this case, we should be writing NULLFSINO rather than nothing to
ensure that we leave the group quota inode in a valid state while
quotas are enabled.

Failure to do so doesn't cause a current kernel to break - the
separate project quota inodes introduced translation code to always
treat a zero inode as NULLFSINO. This was introduced by commit
0102629 ("xfs: Initialize all quota inodes to be NULLFSINO") with is
also in 3.12 but older kernels do not do this and hence taking a
filesystem back to an older kernel can result in quotas failing
initialisation at mount time. When that happens, we see this in
dmesg:

[ 1649.215390] XFS (sdb): Mounting Filesystem
[ 1649.316894] XFS (sdb): Failed to initialize disk quotas.
[ 1649.316902] XFS (sdb): Ending clean mount

By ensuring that we write NULLFSINO to quota inodes that aren't
active, we avoid this problem. We have to be really careful when
determining if the quota inodes are active or not, because we don't
want to write a NULLFSINO if the quota inodes are active and we
simply aren't updating them.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 07:28:41 +10:00
Dave Chinner
cf11da9c5d xfs: refine the allocation stack switch
The allocation stack switch at xfs_bmapi_allocate() has served it's
purpose, but is no longer a sufficient solution to the stack usage
problem we have in the XFS allocation path.

Whilst the kernel stack size is now 16k, that is not a valid reason
for undoing all our "keep stack usage down" modifications. What it
does allow us to do is have the freedom to refine and perfect the
modifications knowing that if we get it wrong it won't blow up in
our faces - we have a safety net now.

This is important because we still have the issue of older kernels
having smaller stacks and that they are still supported and are
demonstrating a wide range of different stack overflows.  Red Hat
has several open bugs for allocation based stack overflows from
directory modifications and direct IO block allocation and these
problems still need to be solved. If we can solve them upstream,
then distro's won't need to bake their own unique solutions.

To that end, I've observed that every allocation based stack
overflow report has had a specific characteristic - it has happened
during or directly after a bmap btree block split. That event
requires a new block to be allocated to the tree, and so we
effectively stack one allocation stack on top of another, and that's
when we get into trouble.

A further observation is that bmap btree block splits are much rarer
than writeback allocation - over a range of different workloads I've
observed the ratio of bmap btree inserts to splits ranges from 100:1
(xfstests run) to 10000:1 (local VM image server with sparse files
that range in the hundreds of thousands to millions of extents).
Either way, bmap btree split events are much, much rarer than
allocation events.

Finally, we have to move the kswapd state to the allocation workqueue
work when allocation is done on behalf of kswapd. This is proving to
cause significant perturbation in performance under memory pressure
and appears to be generating allocation deadlock warnings under some
workloads, so avoiding the use of a workqueue for the majority of
kswapd writeback allocation will minimise the impact of such
behaviour.

Hence it makes sense to move the stack switch to xfs_btree_split()
and only do it for bmap btree splits. Stack switches during
allocation will be much rarer, so there won't be significant
performacne overhead caused by switching stacks. The worse case
stack from all allocation paths will be split, not just writeback.
And the majority of memory allocations will be done in the correct
context (e.g. kswapd) without causing additional latency, and so we
simplify the memory reclaim interactions between processes,
workqueues and kswapd.

The worst stack I've been able to generate with this patch in place
is 5600 bytes deep. It's very revealing because we exit XFS at:

37)     1768      64   kmem_cache_alloc+0x13b/0x170

about 1800 bytes of stack consumed, and the remaining 3800 bytes
(and 36 functions) is memory reclaim, swap and the IO stack. And
this occurs in the inode allocation from an open(O_CREAT) syscall,
not writeback.

The amount of stack being used is much less than I've previously be
able to generate - fs_mark testing has been able to generate stack
usage of around 7k without too much trouble; with this patch it's
only just getting to 5.5k. This is primarily because the metadata
allocation paths (e.g. directory blocks) are no longer causing
double splits on the same stack, and hence now stack tracing is
showing swapping being the worst stack consumer rather than XFS.

Performance of fs_mark inode create workloads is unchanged.
Performance of fs_mark async fsync workloads is consistently good
with context switches reduced by around 150,000/s (30%).
Performance of dbench, streaming IO and postmark is unchanged.
Allocation deadlock warnings have not been seen on the workloads
that generated them since adding this patch.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 07:08:24 +10:00
Dave Chinner
aa182e64f1 Revert "xfs: block allocation work needs to be kswapd aware"
This reverts commit 1f6d64829d.

This commit resulted in regressions in performance in low
memory situations where kswapd was doing writeback of delayed
allocation blocks. It resulted in significant parallelism of the
kswapd work and with the special kswapd flags meant that hundreds of
active allocation could dip into kswapd specific memory reserves and
avoid being throttled. This cause a large amount of performance
variation, as well as random OOM-killer invocations that didn't
previously exist.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-07-15 07:08:10 +10:00
Dave Chinner
2451337dd0 xfs: global error sign conversion
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 <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:58:08 +10:00
Dave Chinner
30f712c9dd libxfs: move source files
Move all the source files that are shared with userspace into
libxfs/. This is done as one big chunk simpy to get it done
quickly

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:57:53 +10:00
Dave Chinner
84be0ffc90 libxfs: move header files
Move all the header files that are shared with userspace into
libxfs. This is done as one big chunk simpy to get it done quickly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:57:36 +10:00
Dave Chinner
69116a1317 xfs: create libxfs infrastructure
To minimise the differences between kernel and userspace code,
split the kernel code into the same structure as the userspace code.
That is, the gneric core functionality of XFS is moved to a libxfs/
directory and treat it as a layering barrier in the XFS code.

This patch introduces the libxfs directory, the build infrastructure
and an initial source and header file to build. The libxfs directory
will contain the header files that are needed to build libxfs - most
of userspace does not care about the location of these header files
as they are accessed indirectly. Hence keeping them inside libxfs
makes it easy to track the changes and script the sync process as
the directory structure will be identical.

To allow this changeover to occur in the kernel code, there are some
temporary infrastructure in the makefiles to grab the header
filesystem from both locations. Once all the files are moved,
modifications will be made in the source code that will make the
need for these include directives go away.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-25 14:57:22 +10:00
Eric Sandeen
b474c7ae43 xfs: Nuke XFS_ERROR macro
XFS_ERROR was designed long ago to trap return values, but it's not
runtime configurable, it's not consistently used, and we can do
similar error trapping with ftrace scripts and triggers from
userspace.

Just nuke XFS_ERROR and associated bits.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-22 15:04:54 +10:00
Eric Sandeen
d99831ff39 xfs: return is not a function
return is not a function.  "return(EIO);" is silly;
"return (EIO);" moreso.  return is not a function.
Nuke the pointless parens.

[dchinner: catch a couple of extra cases in xfs_attr_list.c,
xfs_acl.c and xfs_linux.h.]

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-22 15:03:54 +10:00
Linus Torvalds
16b9057804 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "This the bunch that sat in -next + lock_parent() fix.  This is the
  minimal set; there's more pending stuff.

  In particular, I really hope to get acct.c fixes merged this cycle -
  we need that to deal sanely with delayed-mntput stuff.  In the next
  pile, hopefully - that series is fairly short and localized
  (kernel/acct.c, fs/super.c and fs/namespace.c).  In this pile: more
  iov_iter work.  Most of prereqs for ->splice_write with sane locking
  order are there and Kent's dio rewrite would also fit nicely on top of
  this pile"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (70 commits)
  lock_parent: don't step on stale ->d_parent of all-but-freed one
  kill generic_file_splice_write()
  ceph: switch to iter_file_splice_write()
  shmem: switch to iter_file_splice_write()
  nfs: switch to iter_splice_write_file()
  fs/splice.c: remove unneeded exports
  ocfs2: switch to iter_file_splice_write()
  ->splice_write() via ->write_iter()
  bio_vec-backed iov_iter
  optimize copy_page_{to,from}_iter()
  bury generic_file_aio_{read,write}
  lustre: get rid of messing with iovecs
  ceph: switch to ->write_iter()
  ceph_sync_direct_write: stop poking into iov_iter guts
  ceph_sync_read: stop poking into iov_iter guts
  new helper: copy_page_from_iter()
  fuse: switch to ->write_iter()
  btrfs: switch to ->write_iter()
  ocfs2: switch to ->write_iter()
  xfs: switch to ->write_iter()
  ...
2014-06-12 10:30:18 -07:00
Al Viro
9c1d5284c7 Merge commit '9f12600fe425bc28f0ccba034a77783c09c15af4' into for-linus
Backmerge of dcache.c changes from mainline.  It's that, or complete
rebase...

Conflicts:
	fs/splice.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-12 00:28:09 -04:00
Al Viro
8d0207652c ->splice_write() via ->write_iter()
iter_file_splice_write() - a ->splice_write() instance that gathers the
pipe buffers, builds a bio_vec-based iov_iter covering those and feeds
it to ->write_iter().  A bunch of simple cases coverted to that...

[AV: fixed the braino spotted by Cyrill]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-06-12 00:18:51 -04:00
Linus Torvalds
412dd3a6da xfs: update for 3.16-rc1
This update contains:
 o cleanup removing unused function args
 o rework of the filestreams allocator to use dentry cache parent lookups
 o new on-disk free inode btree and optimised inode allocator
 o various bug fixes
 o rework of internal attribute API
 o cleanup of superblock feature bit support to remove historic cruft
 o more fixes and minor cleanups
 o added a new directory/attribute geometry abstraction
 o yet more fixes and minor cleanups.
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Merge tag 'xfs-for-linus-3.16-rc1' of git://oss.sgi.com/xfs/xfs

Pull xfs updates from Dave Chinner:
 "This update contains:
   - cleanup removing unused function args
   - rework of the filestreams allocator to use dentry cache parent
     lookups
   - new on-disk free inode btree and optimised inode allocator
   - various bug fixes
   - rework of internal attribute API
   - cleanup of superblock feature bit support to remove historic cruft
   - more fixes and minor cleanups
   - added a new directory/attribute geometry abstraction
   - yet more fixes and minor cleanups"

* tag 'xfs-for-linus-3.16-rc1' of git://oss.sgi.com/xfs/xfs: (86 commits)
  xfs: fix xfs_da_args sparse warning in xfs_readdir
  xfs: Fix rounding in xfs_alloc_fix_len()
  xfs: tone down writepage/releasepage WARN_ONs
  xfs: small cleanup in xfs_lowbit64()
  xfs: kill xfs_buf_geterror()
  xfs: xfs_readsb needs to check for magic numbers
  xfs: block allocation work needs to be kswapd aware
  xfs: remove redundant geometry information from xfs_da_state
  xfs: replace attr LBSIZE with xfs_da_geometry
  xfs: pass xfs_da_args to xfs_attr_leaf_newentsize
  xfs: use xfs_da_geometry for block size in attr code
  xfs: remove mp->m_dir_geo from directory logging
  xfs: reduce direct usage of mp->m_dir_geo
  xfs: move node entry counts to xfs_da_geometry
  xfs: convert dir/attr btree threshold to xfs_da_geometry
  xfs: convert m_dirblksize to xfs_da_geometry
  xfs: convert m_dirblkfsbs to xfs_da_geometry
  xfs: convert directory segment limits to xfs_da_geometry
  xfs: convert directory db conversion to xfs_da_geometry
  xfs: convert directory dablk conversion to xfs_da_geometry
  ...
2014-06-11 09:03:47 -07:00
Andy Lutomirski
23adbe12ef fs,userns: Change inode_capable to capable_wrt_inode_uidgid
The kernel has no concept of capabilities with respect to inodes; inodes
exist independently of namespaces.  For example, inode_capable(inode,
CAP_LINUX_IMMUTABLE) would be nonsense.

This patch changes inode_capable to check for uid and gid mappings and
renames it to capable_wrt_inode_uidgid, which should make it more
obvious what it does.

Fixes CVE-2014-4014.

Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: stable@vger.kernel.org
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-10 13:57:22 -07:00
Dave Chinner
7691283d05 Merge branch 'xfs-misc-fixes-3-for-3.16' into for-next 2014-06-10 07:32:56 +10:00
Dave Chinner
8612c7e594 Merge branch 'xfs-da-geom' into for-next 2014-06-10 07:32:41 +10:00
Dave Chinner
35f46c5f04 xfs: fix xfs_da_args sparse warning in xfs_readdir
The kbuild test robot reported:

>> fs/xfs/xfs_dir2_readdir.c:672:41: sparse: Using plain integer as NULL pointer

Fix it.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-10 07:30:36 +10:00
Jan Kara
30265117ee xfs: Fix rounding in xfs_alloc_fix_len()
Rounding in xfs_alloc_fix_len() is wrong. As the comment states, the
result should be a number of a form (k*prod+mod) however due to sign
mistake the result is different. As a result allocations on raid arrays
could be misaligned in some cases.

This also seems to fix occasional assertion failure:
	XFS_WANT_CORRUPTED_GOTO(rlen <= flen, error0)
in xfs_alloc_ag_vextent_size().

Also add an assertion that the result of xfs_alloc_fix_len() is of
expected form.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 16:06:37 +10:00
Christoph Hellwig
448011e2ab xfs: tone down writepage/releasepage WARN_ONs
I recently ran into the issue fixed by

  "xfs: kill buffers over failed write ranges properly"

which spams the log with lots of backtraces.  Make debugging any
issues like that easier by using WARN_ON_ONCE in the writeback code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 16:05:15 +10:00
Dan Carpenter
72208ee060 xfs: small cleanup in xfs_lowbit64()
There are two checkpatch.pl complaints here because of the bad
indenting and because of the assignment inside the condition.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 16:04:42 +10:00
Dave Chinner
36de95567f xfs: kill xfs_buf_geterror()
Most of the callers are just calling ASSERT(!xfs_buf_geterror())
which means they are checking for bp->b_error == 0. If bp is null in
this case, we will assert fail, and hence it's no different in
result to oopsing because of a null bp. In some cases, errors have
already been checked for or the function returning the buffer can't
return a buffer with an error, so it's just a redundant assert.
Either way, the assert can either be removed.

The other two non-assert callers can just test for a buffer and
error properly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 16:02:12 +10:00
Dave Chinner
556b8883cf xfs: xfs_readsb needs to check for magic numbers
Commit daba542 ("xfs: skip verification on initial "guess"
superblock read") dropped the use of a verifier for the initial
superblock read so we can probe the sector size of the filesystem
stored in the superblock. It, however, now fails to validate that
what was read initially is actually an XFS superblock and hence will
fail the sector size check and return ENOSYS.

This causes probe-based mounts to fail because it expects XFS to
return EINVAL when it doesn't recognise the superblock format.

cc: <stable@vger.kernel.org>
Reported-by: Plamen Petrov <plamen.sisi@gmail.com>
Tested-by: Plamen Petrov <plamen.sisi@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 16:00:43 +10:00
Dave Chinner
1f6d64829d xfs: block allocation work needs to be kswapd aware
Upon memory pressure, kswapd calls xfs_vm_writepage() from
shrink_page_list(). This can result in delayed allocation occurring
and that gets deferred to the the allocation workqueue.

The allocation then runs outside kswapd context, which means if it
needs memory (and it does to demand page metadata from disk) it can
block in shrink_inactive_list() waiting for IO congestion. These
blocking waits are normally avoiding in kswapd context, so under
memory pressure writeback from kswapd can be arbitrarily delayed by
memory reclaim.

To avoid this, pass the kswapd context to the allocation being done
by the workqueue, so that memory reclaim understands correctly that
the work is being done for kswapd and therefore it is not blocked
and does not delay memory reclaim.

To avoid issues with int->char conversion of flag fields (as noticed
in v1 of this patch) convert the flag fields in the struct
xfs_bmalloca to bool types. pahole indicates these variables are
still single byte variables, so no extra space is consumed by this
change.

cc: <stable@vger.kernel.org>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 15:59:59 +10:00
Dave Chinner
b2a21e7a6b xfs: remove redundant geometry information from xfs_da_state
It's carried in state->args->geo, so there's no need to duplicate it
and use more stack space than necessary.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 15:22:04 +10:00
Dave Chinner
c2c4c477e0 xfs: replace attr LBSIZE with xfs_da_geometry
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 15:21:45 +10:00
Dave Chinner
c59f0ad23a xfs: pass xfs_da_args to xfs_attr_leaf_newentsize
As it's only ever called from contexts where the xfs_da_args is
present and contains all the information needed inside the args
structure.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-06-06 15:21:27 +10:00