NULL.

Patch provided by Eric Sandeen.

SGI-PV: 961693
SGI-Modid: xfs-linux-melb:xfs-kern:28199a
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

Fixes a few small issues (mostly cosmetic) that were picked up during the
review cycle for the last set of freeze path changes.

SGI-PV: 959267
SGI-Modid: xfs-linux-melb:xfs-kern:28035a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>

record.

The current Linux XFS freeze code is a mess. We flush the metadata buffers
out while we are still allowing new transactions to start and then fail to
flush the dirty buffers back out before writing the unmount and dummy
records to the log.

This leads to problems when the frozen filesystem is used for snapshots -
we do log recovery on a readonly image and often it appears that the log
image in the snapshot is not correct. Hence we end up with hangs, oops and
mount failures when trying to mount a snapshot image that has been created
when the filesystem has not been correctly frozen.

To fix this, we need to move th metadata flush to after we wait for all
current transactions to complete in teh second stage of the freeze. This
means that when we write the final log records, the log should be clean
and recovery should never occur on a snapshot image created from a frozen
filesystem.

SGI-PV: 959267
SGI-Modid: xfs-linux-melb:xfs-kern:28010a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NDonald Douwsma <donaldd@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

The block reservation mechanism has been broken since the per-cpu
superblock counters were introduced. Make the block reservation code work
with the per-cpu counters by syncing the counters, snapshotting the amount
of available space and then doing a modifcation of the counter state
according to the result. Continue in a loop until we either have no space
available or we reserve some space.

SGI-PV: 956323
SGI-Modid: xfs-linux-melb:xfs-kern:27895a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NTim Shimmin <tes@sgi.com>

SGI-PV: 959137
SGI-Modid: xfs-linux-melb:xfs-kern:27710a
Signed-off-by: NLachlan McIlroy <lachlan@sgi.com>
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NTim Shimmin <tes@sgi.com>

SGI-PV: 955302
SGI-Modid: xfs-linux-melb:xfs-kern:26907a
Signed-off-by: NNathan Scott <nathans@sgi.com>
Signed-off-by: NTim Shimmin <tes@sgi.com>

The fix for recent ENOSPC deadlocks introduced certain limitations on
allocations. The fix could cause xfssyncd to loop endlessly if we did not
leave some space free for the allocator to work correctly. Basically, we
needed to ensure that we had at least 4 blocks free for an AG free list
and a block for the inode bmap btree at all times.

However, this did not take into account the fact that each AG has a free
list that needs 4 blocks. Hence any filesystem with more than one AG could
cause oversubscription of free space and make xfssyncd spin forever trying
to allocate space needed for AG freelists that was not available in the
AG.

The following patch reserves space for the free lists in all AGs plus the
inode bmap btree which prevents oversubscription. It also prevents those
blocks from being reported as free space (as they can never be used) and
makes the SMP in-core superblock accounting code and the reserved block
ioctl respect this requirement.

SGI-PV: 955674
SGI-Modid: xfs-linux-melb:xfs-kern:26894a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NDavid Chatterton <chatz@sgi.com>

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:26622a
Signed-off-by: NNathan Scott <nathans@sgi.com>

pure bloat.

SGI-PV: 952969
SGI-Modid: xfs-linux-melb:xfs-kern:26251a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 904196
SGI-Modid: xfs-linux-melb:xfs-kern:26201a
Signed-off-by: NNathan Scott <nathans@sgi.com>

porters.

SGI-PV: 953338
SGI-Modid: xfs-linux-melb:xfs-kern:26108a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 953338
SGI-Modid: xfs-linux-melb:xfs-kern:26107a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 9533338
SGI-Modid: xfs-linux-melb:xfs-kern:26106a
Signed-off-by: NNathan Scott <nathans@sgi.com>

interface.

SGI-PV: 953338
SGI-Modid: xfs-linux-melb:xfs-kern:26103a
Signed-off-by: NNathan Scott <nathans@sgi.com>

with remount,ro.

SGI-PV: 951944
SGI-Modid: xfs-linux-melb:xfs-kern:25742a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:25634a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 951299
SGI-Modid: xfs-linux-melb:xfs-kern:25632a
Signed-off-by: NNathan Scott <nathans@sgi.com>

these typos.

SGI-PV: 904196
SGI-Modid: xfs-linux-melb:xfs-kern:25539a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 951200
SGI-Modid: xfs-linux-melb:xfs-kern:25535a
Signed-off-by: NNathan Scott <nathans@sgi.com>

Engelhardt.

SGI-PV: 947038
SGI-Modid: xfs-linux-melb:xfs-kern:25529a
Signed-off-by: NNathan Scott <nathans@sgi.com>

detected.  Thanks to Roger Willcocks.

SGI-PV: 951054
SGI-Modid: xfs-linux-melb:xfs-kern:25477a
Signed-off-by: NNathan Scott <nathans@sgi.com>

be passed.

SGI-PV: 949073
SGI-Modid: xfs-linux-melb:xfs-kern:25122a
Signed-off-by: NNathan Scott <nathans@sgi.com>

threads, the incore superblock lock becomes the limiting factor for
buffered write throughput. Make the contended fields in the incore
superblock use per-cpu counters so that there is no global lock to limit
scalability.

SGI-PV: 946630
SGI-Modid: xfs-linux-melb:xfs-kern:25106a
Signed-off-by: NDavid Chinner <dgc@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

actually use it.  Kill this dead code.	Signed-off-by: Christoph Hellwig
<hch@lst.de>

SGI-PV: 904196
SGI-Modid: xfs-linux-melb:xfs-kern:25086a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 946760
SGI-Modid: xfs-linux-melb:xfs-kern:24765a
Signed-off-by: NNathan Scott <nathans@sgi.com>

understood.

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:202962a
Signed-off-by: NNathan Scott <nathans@sgi.com>

consistent.

SGI-PV: 941645
SGI-Modid: xfs-linux-melb:xfs-kern:202961a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 945483
SGI-Modid: xfs-linux-melb:xfs-kern:202638a
Signed-off-by: NChristoph Hellwig <hch@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

filesystem

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:202355a
Signed-off-by: NChristoph Hellwig <hch@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

in showargs.

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:24383a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 912426
SGI-Modid: xfs-linux-melb:xfs-kern:201981a
Signed-off-by: NChristoph Hellwig <hch@sgi.com>
Signed-off-by: NNathan Scott <nathans@sgi.com>

set default flags.

SGI-PV: 945242
SGI-Modid: xfs-linux-melb:xfs-kern:24292a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 944821
SGI-Modid: xfs-linux:xfs-kern:24213a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 937127
SGI-Modid: xfs-linux:xfs-kern:24201a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 943866
SGI-Modid: xfs-linux:xfs-kern:24030a
Signed-off-by: NNathan Scott <nathans@sgi.com>

it.

SGI-PV: 941645
SGI-Modid: xfs-linux:xfs-kern:24002a
Signed-off-by: NNathan Scott <nathans@sgi.com>

code.

SGI-PV: 941645
SGI-Modid: xfs-linux:xfs-kern:23926a
Signed-off-by: NNathan Scott <nathans@sgi.com>

boilerplate.

SGI-PV: 913862
SGI-Modid: xfs-linux:xfs-kern:23903a
Signed-off-by: NNathan Scott <nathans@sgi.com>

SGI-PV: 943122
SGI-Modid: xfs-linux:xfs-kern:23901a
Signed-off-by: NNathan Scott <nathans@sgi.com>

/proc/mounts.

SGI-PV: 942984
SGI-Modid: xfs-linux:xfs-kern:23862a
Signed-off-by: NNathan Scott <nathans@sgi.com>