Commit Graph

1730 Commits

Author SHA1 Message Date
Christoph Hellwig 046f1685bb xfs: remove iomap_target
Instead of using the iomap_target field in struct xfs_iomap
and the IOMAP_REALTIME flag just use the already existing
xfs_find_bdev_for_inode helper.  There's some fallout as we
need to pass the inode in a few more places, which we also
use to sanitize some calling conventions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:16 -05:00
Christoph Hellwig 826bf0adce xfs: limit xfs_imap_to_bmap to a single mapping
We only call xfs_iomap for single mappings anyway, so remove all
code dealing with multiple mappings from xfs_imap_to_bmap and add
asserts that we never get results that we do not expect.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:16 -05:00
Christoph Hellwig 4a5224d7b1 xfs: simplify buffer to transaction matching
We currenly have a routine xfs_trans_buf_item_match_all which checks
if any log item in a transaction contains a given buffer, and a
second one that only does this check for the first, embedded chunk
of log items.  We only use the second routine if we know we only
have that log item chunk, so get rid of the limited routine and
always use the more complete one.

Also rename the old xfs_trans_buf_item_match_all to
xfs_trans_buf_item_match and update various surrounding comments,
and move the remaining xfs_trans_buf_item_match on top of the file
to avoid a forward prototype.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:16 -05:00
Tao Ma 2d1ff3c75a xfs: Make fiemap work in query mode.
According to Documentation/filesystems/fiemap.txt, If fm_extent_count
is zero, then the fm_extents[] array is ignored (no extents will be
returned), and the fm_mapped_extents count will hold the number of
extents needed.

But as the commit 97db39a1f6 has changed
bmv_count to the caller's input buffer, this number query function can't
work any more. As this commit is written to change bmv_count from
MAXEXTNUM because of ENOMEM.

This patch just try to  set bm.bmv_count to something sane.
Thanks to Dave Chinner <david@fromorbit.com> for the suggestion.

Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-05-19 09:58:16 -05:00
Alex Elder 48389ef175 xfs: kill off l_sectbb_mask
There remains only one user of the l_sectbb_mask field in the log
structure.  Just kill it off and compute the mask where needed from
the power-of-2 sector size.

(Only update from last post is to accomodate the changes in the
previous patch in the series.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:16 -05:00
Alex Elder 69ce58f08a xfs: record log sector size rather than log2(that)
Change struct log so it keeps track of the size (in basic blocks) of
a log sector in l_sectBBsize rather than the log-base-2 of that
value (previously, l_sectbb_log).  The name was chosen for
consistency with the other fields in the structure that represent
a number of basic blocks.

(Updated so that a variable used in computing and verifying a log's
sector size is named "log2_size".  Also added the "BB" to the
structure field name, based on feedback from Eric Sandeen.  Also
dropped some superfluous parentheses.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
2010-05-19 09:58:15 -05:00
Christoph Hellwig 1414a6046a xfs: remove dead XFS_LOUD_RECOVERY code
This can't be enabled through the build system and has been dead for
ages.  Note that the CRC patches add back log checksumming, but the
code is quite different from the version removed here anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:15 -05:00
Christoph Hellwig 8112e9dc6d xfs: removed unused XFS_QMOPT_ flags
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:15 -05:00
Christoph Hellwig 191f8488f9 xfs: remove a few macro indirections in the quota code
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:15 -05:00
Christoph Hellwig 8a7b8a89a3 xfs: access quotainfo structure directly
Access fields in m_quotainfo directly instead of hiding them behind the
XFS_QI_* macros.  Add local variables for the quotainfo pointer in places
where we have lots of them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:14 -05:00
Christoph Hellwig 37bc5743fd xfs: wait for direct I/O to complete in fsync and write_inode
We need to wait for all pending direct I/O requests before taking care of
metadata in fsync and write_inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:14 -05:00
Andrea Gelmini fce1cad651 xfs: xfs_trace.c: duplicated include
fs/xfs/linux-2.6/xfs_trace.c: xfs_attr_sf.h is included more than once.

Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:14 -05:00
Alex Elder 3f943d853d xfs: minor odds and ends in xfs_log_recover.c
Odds and ends in "xfs_log_recover.c".  This patch just contains some
minor things that didn't seem to warrant their own individual
patches:
- In xlog_bread_noalign(), drop an assertion that a pointer is
  non-null (the crash will tell us it was a bad pointer).
- Add a more descriptive header comment for xlog_find_verify_cycle().
- Make a few additions to the comments in xlog_find_head().  Also
  rearrange some expressions in a few spots to produce the same
  result, but in a way that seems more clear what's being computed.

(Updated in response to Dave's review comments.  Note I did not
split this patch like I said I would.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:14 -05:00
Alex Elder e3bb2e30d5 xfs: avoid repeated pointer dereferences
In xlog_find_cycle_start() use a local variable for some repeated
operations rather than constantly accessing the memory location
whose address is passed in.

(This version drops an assertion that a pointer is non-null.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:14 -05:00
Alex Elder 9db127edb5 xfs: change a few labels in xfs_log_recover.c
Rename a label used in xlog_find_head() that I thought was poorly
chosen.  Also combine two adjacent labels xlog_find_tail() into a
single label, and give it a more generic name.

(Now using Dave's suggested "validate_head" name for first label.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:13 -05:00
Christoph Hellwig 8c38366f99 xfs: enforce synchronous writes in xfs_bwrite
xfs_bwrite is used with the intention of synchronously writing out
buffers, but currently it does not actually clear the async flag if
that's left from previous writes but instead implements async
behaviour if it finds it.  Remove the code handling asynchronous
writes as we've got rid of those entirely outside of the log and
delwri buffers, and make sure that we clear the async and read flags
before writing the buffer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:13 -05:00
Christoph Hellwig df308bcfec xfs: remove periodic superblock writeback
All modifications to the superblock are done transactional through
xfs_trans_log_buf, so there is no reason to initiate periodic
asynchronous writeback.  This only removes the superblock from the
delwri list and will lead to sub-optimal I/O scheduling.

Cut down xfs_sync_fsdata now that it's only used for synchronous
superblock writes and move the log coverage checks into the two
callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-05-19 09:58:13 -05:00
Dave Chinner f983710758 xfs: make the log ticket transaction id random
The transaction ID that is written to the log for a transaction is
currently set by taking the lower 32 bits of the memory address of
the ticket structure.  This is not guaranteed to be unique as
tickets comes from a slab and slots can be reallocated immediately
after being freed. As a result, there is no guarantee of uniqueness
in the ticket ID value.

Fix this by assigning a random number to the ticket ID field so that
it is extremely unlikely that duplicates will occur and remove the
possibility of transactions being mixed up during recovery due to
duplicate IDs.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:13 -05:00
Alex Elder 36adecff50 xfs: nothing special about 1-block log sector
There are a number of places where a log sector size of 1 uses
special case code.  The round_up() and round_down() macros
produce the correct result even when the log sector size is 1, and
this eliminates the need for treating this as a special case.

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:12 -05:00
Alex Elder ff30a6221d xfs: encapsulate bbcount validity checking
Define a function that encapsulates checking the validity of a log
block count.

(Updated from previous version--no longer includes error reporting in the
encapsulated validation function.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:12 -05:00
Alex Elder 5c17f5339f xfs: kill XLOG_SECTOR_ROUND*()
XLOG_SECTOR_ROUNDUP_BBCOUNT() and XLOG_SECTOR_ROUNDDOWN_BLKNO()
are now fairly simple macro translations.  Just get rid of them in
favor of the round_up() and round_down() macro calls they represent.

Also, in spots in xlog_get_bp() and xlog_write_log_records(),
round_up() was being called with value 1, which just evaluates
to the macro's second argument; so just use that instead.
In the latter case, make use of that value, as long as it's
already been computed.

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:12 -05:00
Alex Elder 8511998baa xfs: simplify XLOG_SECTOR_ROUND*()
XLOG_SECTOR_ROUNDUP_BBCOUNT() is defined in "fs/xfs/xfs_log_recover.c"
in an overly-complicated way.  It is basically roundup(), but that
is not at all clear from its definition.  (Actually, there is
another macro round_up() that applies for power-of-two-based masks
which I'll be using here.)

The operands in XLOG_SECTOR_ROUNDUP_BBCOUNT() are basically the
block number (bbs) and the log sector basic block mask
(log->l_sectbb_mask).  I'll call them B and M for this discussion.

The macro computes is value this way:
	M && (B & M) ? (B + M + 1) & ~M : B

Put another way, we can break it into 3 cases:
	1)  ! M          -> B			# 0 mask, no effect
	2)  ! (B & M)    -> B			# sector aligned
	3)  M && (B & M) -> (B + M + 1) & ~M	# round up otherwise

The round_up() macro is cleverly defined using a value, v, and a
power-of-2, p, and the result is the nearest multiple of p greater
than or equal to v.  Its value is computed something like this:
	((v - 1) | (p - 1)) + 1
Let's consider using this in the context of the 3 cases above.

When p = 2^0 = 1, the result boils down to ((v - 1) | 0) + 1, so it
just translates any value v to itself.  That handles case (1) above.

When p = 2^n, n > 0, we know that (p - 1) will be a mask with all n
bits 0..n-1 set.  The condition in this case occurs when none of
those mask bits is set in the value v provided.  If that is the
case, subtracting 1 from v will have 1's in all those lower bits (at
least).  Therefore, OR-ing the mask with that decremented value has
no effect, so adding the 1 back again will just translate the v to
itself.  This handles case (2).

Otherwise, the value v is greater than some multiple of p, and
decrementing it will produce a result greater than or equal to that
multiple.  OR-ing in the mask will produce a value 1 less than the
next multiple of p, so finally adding 1 back will result in the
desired rounded-up value.  This handles case (3).

Hopefully this is convincing.

While I was at it, I converted XLOG_SECTOR_ROUNDDOWN_BLKNO() to use
the round_down() macro.

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:12 -05:00
Alex Elder 6881a229f6 xfs: fix min bufsize bugs in two places
This fixes a bug in two places that I found by inspection.  In
xlog_find_verify_cycle() and xlog_write_log_records(), the code
attempts to allocate a buffer to hold as many blocks as possible.
It gives up if the number of blocks to be allocated gets too small.
Right now it uses log->l_sectbb_log as that lower bound, but I'm
sure it's supposed to be the actual log sector size instead.  That
is, the lower bound should be (1 << log->l_sectbb_log).

Also define a simple macro xlog_sectbb(log) to represent the number
of basic blocks in a sector for the given log.

(No change from original submission; I have implemented Christoph's
suggestion about storing l_sectsize rather than l_sectbb_log in
a new, separate patch in this series.)

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:12 -05:00
Alex Elder a0e856b0b4 xfs: add const qualifiers to xfs error function args
Change the tag and file name arguments to xfs_error_report() and
xfs_corruption_error() to use a const qualifier.

Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:11 -05:00
Christoph Hellwig 74457cf4a3 xfs: remove xfs_dqmarker
The xfs_dqmarker structure does not need to exist anymore. Move the
remaining flags field out of it and remove the structure altogether.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:11 -05:00
Dave Chinner 3a8406f6d6 xfs: convert the dquot free list to use list heads
Convert the dquot free list on the filesystem to use listhead
infrastructure rather than the roll-your-own in the quota code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:11 -05:00
Dave Chinner e6a81f13aa xfs: convert the dquot hash list to use list heads
Convert the dquot hash list on the filesystem to use listhead
infrastructure rather than the roll-your-own in the quota code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:11 -05:00
Dave Chinner 368e136174 xfs: remove duplicate code from dquot reclaim
The dquot shaker and the free-list reclaim code use exactly the same
algorithm but the code is duplicated and slightly different in each
case. Make the shaker code use the single dquot reclaim code to
remove the code duplication.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:11 -05:00
Dave Chinner 3a25404b3f xfs: convert the per-mount dquot list to use list heads
Convert the dquot list on the filesytesm to use listhead
infrastructure rather than the roll-your-own in the quota code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:10 -05:00
Dave Chinner 9abbc539bf xfs: add log item recovery tracing
Currently there is no tracing in log recovery, so it is difficult to
determine what is going on when something goes wrong.

Add tracing for log item recovery to provide visibility into the log
recovery process. The tracing added shows regions being extracted
from the log transactions and added to the transaction hash forming
recovery items, followed by the reordering, cancelling and finally
recovery of the items.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:10 -05:00
Christoph Hellwig e6b1f27370 xfs: clean up xlog_write_adv_cnt
Replace the awkward xlog_write_adv_cnt with an inline helper that makes
it more obvious that it's modifying it's paramters, and replace the use
of an integer type for "ptr" with a real void pointer.  Also move
xlog_write_adv_cnt to xfs_log_priv.h as it will be used outside of
xfs_log.c in the delayed logging series.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:10 -05:00
Dave Chinner 55b66332d0 xfs: introduce new internal log vector structure
The current log IO vector structure is a flat array and not
extensible. To make it possible to keep separate log IO vectors for
individual log items, we need a method of chaining log IO vectors
together.

Introduce a new log vector type that can be used to wrap the
existing log IO vectors on use that internally to the log. This
means that the existing external interface (xfs_log_write) does not
change and hence no changes to the transaction commit code are
required.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:10 -05:00
Christoph Hellwig 99428ad0f6 xfs: reindent xlog_write
Reindent xlog_write to normal one tab indents and move all variable
declarations into the closest enclosing block.

Split from a bigger patch by Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:10 -05:00
Dave Chinner b5203cd0a4 xfs: factor xlog_write
xlog_write is a mess that takes a lot of effort to understand. It is
a mass of nested loops with 4 space indents to get it to fit in 80 columns
and lots of funky variables that aren't obvious what they mean or do.

Break it down into understandable chunks.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2010-05-19 09:58:09 -05:00
Dave Chinner 9b9fc2b760 xfs: log ticket reservation underestimates the number of iclogs
When allocation a ticket for a transaction, the ticket is initialised with the
worst case log space usage based on the number of bytes the transaction may
consume. Part of this calculation is the number of log headers required for the
iclog space used up by the transaction.

This calculation makes an undocumented assumption that if the transaction uses
the log header space reservation on an iclog, then it consumes either the
entire iclog or it completes. That is - the transaction that is first in an
iclog is the transaction that the log header reservation is accounted to. If
the transaction is larger than the iclog, then it will use the entire iclog
itself. Document this assumption.

Further, the current calculation uses the rule that we can fit iclog_size bytes
of transaction data into an iclog. This is in correct - the amount of space
available in an iclog for transaction data is the size of the iclog minus the
space used for log record headers. This means that the calculation is out by
512 bytes per 32k of log space the transaction can consume. This is rarely an
issue because maximally sized transactions are extremely uncommon, and for 4k
block size filesystems maximal transaction reservations are about 400kb. Hence
the error in this case is less than the size of an iclog, so that makes it even
harder to hit.

However, anyone using larger directory blocks (16k directory blocks push the
maximum transaction size to approx. 900k on a 4k block size filesystem) or
larger block size (e.g. 64k blocks push transactions to the 3-4MB size) could
see the error grow to more than an iclog and at this point the transaction is
guaranteed to get a reservation underrun and shutdown the filesystem.

Fix this by adjusting the calculation to calculate the correct number of iclogs
required and account for them all up front.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:09 -05:00
Dave Chinner b1c1b5b610 xfs: Clean up xfs_trans_committed code after factoring
Now that the code has been factored, clean up all the remaining
style cruft, simplify the code and re-order functions so that it
doesn't need forward declarations.

Also move the remaining functions that require forward declarations
(xfs_trans_uncommit, xfs_trans_free) so that all the forward
declarations can be removed from the file.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:09 -05:00
Dave Chinner 8e646a55ac xfs: update and factor xfs_trans_committed()
The function header to xfs-trans_committed has long had this
comment:

 * THIS SHOULD BE REWRITTEN TO USE xfs_trans_next_item()

To prepare for different methods of committing items, convert the
code to use xfs_trans_next_item() and factor the code into smaller,
more digestible chunks.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:09 -05:00
Christoph Hellwig a3ccd2ca43 xfs: clean up xfs_trans_commit logic even more
> +shut_us_down:
> +	shutdown = XFS_FORCED_SHUTDOWN(mp) ? EIO : 0;
> +	if (!(tp->t_flags & XFS_TRANS_DIRTY) || shutdown) {
> +		xfs_trans_unreserve_and_mod_sb(tp);
> +		/*

This whole area in _xfs_trans_commit is still a complete mess.

So while touching this code, unravel this mess as well to make the
whole flow of the function simpler and clearer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:08 -05:00
Dave Chinner 0924378a68 xfs: split out iclog writing from xfs_trans_commit()
Split the the part of xfs_trans_commit() that deals with writing the
transaction into the iclog into a separate function. This isolates the
physical commit process from the logical commit operation and makes
it easier to insert different transaction commit paths without affecting
the existing algorithm adversely.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:08 -05:00
Dave Chinner 713bf88bba xfs: fix reservation release commit flag in xfs_bmap_add_attrfork()
xfs_bmap_add_attrfork() passes XFS_TRANS_PERM_LOG_RES to xfs_trans_commit()
to indicate that the commit should release the permanent log reservation
as part of the commit. This is wrong - the correct flag is
XFS_TRANS_RELEASE_LOG_RES - and it is only by the chance that both these
flags have the value of 0x4 that the code is doing the right thing.

Fix it by changing to use the correct flag.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:08 -05:00
Dave Chinner 8e12385086 xfs: remove stale parameter from ->iop_unpin method
The staleness of a object being unpinned can be directly derived
from the object itself - there is no need to extract it from the
object then pass it as a parameter into IOP_UNPIN().

This means we can kill the XFS_LID_BUF_STALE flag - it is set,
checked and cleared in the same places XFS_BLI_STALE flag in the
xfs_buf_log_item so it is now redundant and hence safe to remove.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:08 -05:00
Dave Chinner 4aaf15d1aa xfs: Add inode pin counts to traces
We don't record pin counts in inode events right now, and this makes
it difficult to track down problems related to pinning inodes. Add
the pin count to the inode trace class and add trace events for
pinning and unpinning inodes.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:08 -05:00
Dave Chinner 43f5efc5b5 xfs: factor log item initialisation
Each log item type does manual initialisation of the log item.
Delayed logging introduces new fields that need initialisation, so
factor all the open coded initialisation into a common function
first.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-05-19 09:58:07 -05:00
Jan Engelhardt e2a07812e9 xfs: add blockdev name to kthreads
This allows to see in `ps` and similar tools which kthreads are
allotted to which block device/filesystem, similar to what jbd2
does. As the process name is a fixed 16-char array, no extra
space is needed in tasks.

  PID TTY      STAT   TIME COMMAND
    2 ?        S      0:00 [kthreadd]
  197 ?        S      0:00  \_ [jbd2/sda2-8]
  198 ?        S      0:00  \_ [ext4-dio-unwrit]
  204 ?        S      0:00  \_ [flush-8:0]
 2647 ?        S      0:00  \_ [xfs_mru_cache]
 2648 ?        S      0:00  \_ [xfslogd/0]
 2649 ?        S      0:00  \_ [xfsdatad/0]
 2650 ?        S      0:00  \_ [xfsconvertd/0]
 2651 ?        S      0:00  \_ [xfsbufd/ram0]
 2652 ?        S      0:00  \_ [xfsaild/ram0]
 2653 ?        S      0:00  \_ [xfssyncd/ram0]

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:07 -05:00
Zhitong Wang fda168c245 xfs: Fix integer overflow in fs/xfs/linux-2.6/xfs_ioctl*.c
The am_hreq.opcount field in the xfs_attrmulti_by_handle() interface
is not bounded correctly. The opcount is used to determine the size
of the buffer required. The size is bounded, but can overflow and so
the size checks may not be sufficient to catch invalid opcounts.
Fix it by catching opcount values that would cause overflows before
calculating the size.

Signed-off-by: Zhitong Wang <zhitong.wangzt@alibaba-inc.com>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-05-19 09:58:07 -05:00
Dave Chinner 9bf729c0af xfs: add a shrinker to background inode reclaim
On low memory boxes or those with highmem, kernel can OOM before the
background reclaims inodes via xfssyncd. Add a shrinker to run inode
reclaim so that it inode reclaim is expedited when memory is low.

This is more complex than it needs to be because the VM folk don't
want a context added to the shrinker infrastructure. Hence we need
to add a global list of XFS mount structures so the shrinker can
traverse them.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-04-29 16:22:13 -05:00
Jens Axboe 7407cf355f Merge branch 'master' into for-2.6.35
Conflicts:
	fs/block_dev.c

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-29 09:36:24 +02:00
Dmitry Monakhov fbd9b09a17 blkdev: generalize flags for blkdev_issue_fn functions
The patch just convert all blkdev_issue_xxx function to common
set of flags. Wait/allocation semantics preserved.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2010-04-28 19:47:36 +02:00
Dave Chinner dd77ef924c xfs: more swap extent fixes for dynamic fork offsets
A new xfsqa test (226) with a prototype xfs_fsr change to try to
handle dynamic fork offsets better triggers an assertion failure
where the inode data fork is in btree format, yet there is room in
the inode for it to be in extent format. The two inodes look like:

before: ino 0x101 (target), num_extents 11, Max in-fork extents 6, broot size 40, fork offset 96
before: ino 0x115 (temp),  num_extents 5, Max in-fork extents 3, broot size 40, fork offset 56
after: ino 0x101 (target), num_extents 5, Max in-fork extents 6, broot size 40, fork offset 96
after: ino 0x115 (temp), num_extents 11, Max in-fork extents 3, broot size 40, fork offset 56

Basically the target inode ends up with 5 extents in btree format,
but it had space for 6 extents in extent format, so ends up
incorrect. Notably here the broot size is the same, and that is
where the kernel code is going wrong - the btree root will fit, so
it lets the swap go ahead.

The check should not allow the swap to take place if the number of
extents while in btree format is less than the number of extents
that can fit in the inode in extent format. Adding that check will
prevent this swap and corruption from occurring.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-04-26 12:38:51 -05:00
Dave Chinner f1d486a361 xfs: don't warn on EAGAIN in inode reclaim
Any inode reclaim flush that returns EAGAIN will result in the inode
reclaim being attempted again later. There is no need to issue a
warning into the logs about this situation.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-04-16 13:51:44 -05:00
Dave Chinner b6f8dd49db xfs: ensure that sync updates the log tail correctly
Updates to the VFS layer removed an extra ->sync_fs call into the
filesystem during the sync process (from the quota code).
Unfortunately the sync code was unknowingly relying on this call to
make sure metadata buffers were flushed via a xfs_buftarg_flush()
call to move the tail of the log forward in memory before the final
transactions of the sync process were issued.

As a result, the old code would write a very recent log tail value
to the log by the end of the sync process, and so a subsequent crash
would leave nothing for log recovery to do. Hence in qa test 182,
log recovery only replayed a small handle for inode fsync
transactions in this case.

However, with the removal of the extra ->sync_fs call, the log tail
was now not moved forward with the inode fsync transactions near the
end of the sync procese the first (and only) buftarg flush occurred
after these transactions went to disk. The result is that log
recovery now sees a large number of transactions for metadata that
is already on disk.

This usually isn't a problem, but when the transactions include
inode chunk allocation, the inode create transactions and all
subsequent changes are replayed as we cannt rely on what is on disk
is valid. As a result, if the inode was written and contains
unlogged changes, the unlogged changes are lost, thereby violating
sync semantics.

The fix is to always issue a transaction after the buftarg flush
occurs is the log iѕ not idle or covered. This results in a dummy
transaction being written that contains the up-to-date log tail
value, which will be very recent. Indeed, it will be at least as
recent as the old code would have left on disk, so log recovery
will behave exactly as it used to in this situation.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-04-16 13:51:23 -05:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Dave Chinner e8c3753ce4 xfs: don't warn about page discards on shutdown
If we are doing a forced shutdown, we can get lots of noise about
delalloc pages being discarded. This is happens by design during a
forced shutdown, so don't spam the logs with these messages.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16 15:40:53 -05:00
Alex Elder 8a262e573d xfs: use scalable vmap API
Re-apply a commit that had been reverted due to regressions
that have since been fixed.

    From 95f8e302c0 Mon Sep 17 00:00:00 2001
    From: Nick Piggin <npiggin@suse.de>
    Date: Tue, 6 Jan 2009 14:43:09 +1100

    Implement XFS's large buffer support with the new vmap APIs. See the vmap
    rewrite (db64fe02) for some numbers. The biggest improvement that comes from
    using the new APIs is avoiding the global KVA allocation lock on every call.

    Signed-off-by: Nick Piggin <npiggin@suse.de>
    Reviewed-by: Christoph Hellwig <hch@infradead.org>
    Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Only modifications here were a minor reformat, plus making the patch
apply given the new use of xfs_buf_is_vmapped().

Modified-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16 15:40:36 -05:00
Alex Elder cd9640a70d xfs: remove old vmap cache
Re-apply a commit that had been reverted due to regressions
that have since been fixed.

    Original commit: d2859751cd
    Author: Nick Piggin <npiggin@suse.de>
    Date: Tue, 6 Jan 2009 14:40:44 +1100

    XFS's vmap batching simply defers a number (up to 64) of vunmaps,
    and keeps track of them in a list. To purge the batch, it just goes
    through the list and calls vunamp on each one. This is pretty poor:
    a global TLB flush is generally still performed on each vunmap, with
    the most expensive parts of the operation being the broadcast IPIs
    and locking involved in the SMP callouts, and the locking involved
    in the vmap management -- none of these are avoided by just batching
    up the calls. I'm actually surprised it ever made much difference.
    (Now that the lazy vmap allocator is upstream, this description is
    not quite right, but the vunmap batching still doesn't seem to do
    much).

    Rip all this logic out of XFS completely. I will improve vmap
    performance and scalability directly in subsequent patch.

    Signed-off-by: Nick Piggin <npiggin@suse.de>
    Reviewed-by: Christoph Hellwig <hch@infradead.org>
    Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

The only change I made was to use the "new" xfs_buf_is_vmapped()
function in a place it had been open-coded in the original.

Modified-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-16 15:40:19 -05:00
Linus Torvalds 66ce3cf84d Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (21 commits)
  xfs: return inode fork offset in bulkstat for fsr
  xfs: Increase the default size of the reserved blocks pool
  xfs: truncate delalloc extents when IO fails in writeback
  xfs: check for more work before sleeping in xfssyncd
  xfs: Fix a build warning in xfs_aops.c
  xfs: fix locking for inode cache radix tree tag updates
  xfs: remove xfs_ipin/xfs_iunpin
  xfs: cleanup xfs_iunpin_wait/xfs_iunpin_nowait
  xfs: kill xfs_lrw.h
  xfs: factor common xfs_trans_bjoin code
  xfs: stop passing opaque handles to xfs_log.c routines
  xfs: split xfs_bmap_btalloc
  xfs: fix xfs_fsblock_t tracing
  xfs: fix inode pincount check in fsync
  xfs: Non-blocking inode locking in IO completion
  xfs: implement optimized fdatasync
  xfs: remove wrapper for the fsync file operation
  xfs: remove wrappers for read/write file operations
  xfs: merge xfs_lrw.c into xfs_file.c
  xfs: fix dquota trace format
  ...
2010-03-06 11:32:21 -08:00
Linus Torvalds 05c5cb31ec Merge branch 'for-2.6.34' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.34' of git://linux-nfs.org/~bfields/linux: (22 commits)
  nfsd4: fix minor memory leak
  svcrpc: treat uid's as unsigned
  nfsd: ensure sockets are closed on error
  Revert "sunrpc: move the close processing after do recvfrom method"
  Revert "sunrpc: fix peername failed on closed listener"
  sunrpc: remove unnecessary svc_xprt_put
  NFSD: NFSv4 callback client should use RPC_TASK_SOFTCONN
  xfs_export_operations.commit_metadata
  commit_metadata export operation replacing nfsd_sync_dir
  lockd: don't clear sm_monitored on nsm_reboot_lookup
  lockd: release reference to nsm_handle in nlm_host_rebooted
  nfsd: Use vfs_fsync_range() in nfsd_commit
  NFSD: Create PF_INET6 listener in write_ports
  SUNRPC: NFS kernel APIs shouldn't return ENOENT for "transport not found"
  SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt()
  NFSD: Support AF_INET6 in svc_addsock() function
  SUNRPC: Use rpc_pton() in ip_map_parse()
  nfsd: 4.1 has an rfc number
  nfsd41: Create the recovery entry for the NFSv4.1 client
  nfsd: use vfs_fsync for non-directories
  ...
2010-03-06 11:31:38 -08:00
Linus Torvalds e213e26ab3 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (33 commits)
  quota: stop using QUOTA_OK / NO_QUOTA
  dquot: cleanup dquot initialize routine
  dquot: move dquot initialization responsibility into the filesystem
  dquot: cleanup dquot drop routine
  dquot: move dquot drop responsibility into the filesystem
  dquot: cleanup dquot transfer routine
  dquot: move dquot transfer responsibility into the filesystem
  dquot: cleanup inode allocation / freeing routines
  dquot: cleanup space allocation / freeing routines
  ext3: add writepage sanity checks
  ext3: Truncate allocated blocks if direct IO write fails to update i_size
  quota: Properly invalidate caches even for filesystems with blocksize < pagesize
  quota: generalize quota transfer interface
  quota: sb_quota state flags cleanup
  jbd: Delay discarding buffers in journal_unmap_buffer
  ext3: quota_write cross block boundary behaviour
  quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota
  quota: split out compat_sys_quotactl support from quota.c
  quota: split out netlink notification support from quota.c
  quota: remove invalid optimization from quota_sync_all
  ...

Fixed trivial conflicts in fs/namei.c and fs/ufs/inode.c
2010-03-05 13:20:53 -08:00
Christoph Hellwig a9185b41a4 pass writeback_control to ->write_inode
This gives the filesystem more information about the writeback that
is happening.  Trond requested this for the NFS unstable write handling,
and other filesystems might benefit from this too by beeing able to
distinguish between the different callers in more detail.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 13:25:52 -05:00
Christoph Hellwig 26821ed40b make sure data is on disk before calling ->write_inode
Similar to the fsync issue fixed a while ago in commit
2daea67e96 we need to write for data to
actually hit the disk before writing out the metadata to guarantee
data integrity for filesystems that modify the inode in the data I/O
completion path.  Currently XFS and NFS handle this manually, and AFS
has a write_inode method that does nothing but waiting for data, while
others are possibly missing out on this.

Fortunately this change has a lot less impact than the fsync change
as none of the write_inode methods starts data writeout of any form
by itself.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-05 13:25:10 -05:00
Alex Elder 9b1f56d60a Merge branch 'for-2.6.34-rc1-batch2' into for-linus 2010-03-05 11:45:03 -06:00
Dave Chinner 07000ee686 xfs: return inode fork offset in bulkstat for fsr
So that fsr can attempt to get the fork offset of the temporary
inode it uses the same as the inode it is defragmenting, pass the
fork offset out in the bulkstat information.

The bulkstat structure has padding that has always been zeroed, so
userspace can tell if this field is set or not by use of the xattr
present flag and a non-zero value for the fork offset.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-05 11:02:07 -06:00
Dave Chinner 8babd8a2e7 xfs: Increase the default size of the reserved blocks pool
The current default size of the reserved blocks pool is easy to deplete
with certain workloads, in particular workloads that do lots of concurrent
delayed allocation extent conversions.  If enough transactions are running
in parallel and the entire pool is consumed then subsequent calls to
xfs_trans_reserve() will fail with ENOSPC.  Also add a rate limited
warning so we know if this starts happening again.

This is an updated version of an old patch from Lachlan McIlroy.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-05 11:01:59 -06:00
Dave Chinner 3ed3a4343b xfs: truncate delalloc extents when IO fails in writeback
We currently use block_invalidatepage() to clean up pages where I/O
fails in ->writepage(). Unfortunately, if the page has delalloc
regions on it, we fail to remove the delalloc regions when we
invalidate the page.  This can result in tripping a BUG() in
xfs_get_blocks() later on if a direct IO read is done on that same
region - the delalloc extent is returned when none is supposed to be
there.

Fix this by truncating away the delalloc regions on the page before
invalidating it. Because they are delalloc, we can do this without
needing a transaction. Indeed - if we get ENOSPC errors, we have to
be able to do this truncation without a transaction as there is
no space left for block reservation (typically why we see a ENOSPC
in writeback).

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-05 11:01:53 -06:00
Dave Chinner 20f6b2c785 xfs: check for more work before sleeping in xfssyncd
xfssyncd processes a queue of work by detaching the queue and
then iterating over all the work items. It then sleeps for a
time period or until new work comes in. If new work is queued
while xfssyncd is actively processing the detached work queue,
it will not process that new work until after a sleep timeout
or the next work event queued wakes it.

Fix this by checking the work queue again before going to sleep.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-05 11:01:45 -06:00
Dave Chinner 694189328a xfs: Fix a build warning in xfs_aops.c
Fix a build warning that slipped through.  Dave Chinner had posted
an updated version of his patch but the previous version--without
this fix--was what got committed.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-05 11:01:22 -06:00
Christoph Hellwig ac0e773718 quota: drop permission checks from xfs_fs_set_xstate/xfs_fs_set_xquota
We already do these checks in the generic code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:25 +01:00
Christoph Hellwig 8c4e4acd66 quota: clean up Q_XQUOTASYNC
Currently Q_XQUOTASYNC calls into the quota_sync method, but XFS does something
entirely different in it than the rest of the filesystems.  xfs_quota which
calls Q_XQUOTASYNC expects an asynchronous data writeout to flush delayed
allocations, while the "VFS" quota support wants to flush changes to the quota
file.

So make Q_XQUOTASYNC call into the writeback code directly and make the
quota_sync method optional as XFS doesn't need in the sense expected by the
rest of the quota code.

GFS2 was using limited XFS-style quota and has a quota_sync method fitting
neither the style used by vfs_quota_sync nor xfs_fs_quota_sync.  I left it
in for now as per discussion with Steve it expects to be called from the
sync path this way.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:24 +01:00
J. Bruce Fields 4ea41e2de5 Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs into for-2.6.34-incoming
Resolve merge conflict in fs/xfs/linux-2.6/xfs_export.c.
2010-03-04 12:04:51 -05:00
Linus Torvalds 0a135ba14d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: add __percpu sparse annotations to what's left
  percpu: add __percpu sparse annotations to fs
  percpu: add __percpu sparse annotations to core kernel subsystems
  local_t: Remove leftover local.h
  this_cpu: Remove pageset_notifier
  this_cpu: Page allocator conversion
  percpu, x86: Generic inc / dec percpu instructions
  local_t: Move local.h include to ringbuffer.c and ring_buffer_benchmark.c
  module: Use this_cpu_xx to dynamically allocate counters
  local_t: Remove cpu_local_xx macros
  percpu: refactor the code in pcpu_[de]populate_chunk()
  percpu: remove compile warnings caused by __verify_pcpu_ptr()
  percpu: make accessors check for percpu pointer in sparse
  percpu: add __percpu for sparse.
  percpu: make access macros universal
  percpu: remove per_cpu__ prefix.
2010-03-03 07:34:18 -08:00
Christoph Hellwig f1f724e4b5 xfs: fix locking for inode cache radix tree tag updates
The radix-tree code requires it's users to serialize tag updates
against other updates to the tree.  While XFS protects tag updates
against each other it does not serialize them against updates of the
tree contents, which can lead to tag corruption.  Fix the inode
cache to always take pag_ici_lock in exclusive mode when updating
radix tree tags.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Patrick Schreurs <patrick@news-service.com>
Tested-by: Patrick Schreurs <patrick@news-service.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 19:14:36 -06:00
Christoph Hellwig a14a5ab58f xfs: remove xfs_ipin/xfs_iunpin
Inodes are only pinned/unpinned via the inode item methods, and lots of
code relies on that fact.  So remove the separate xfs_ipin/xfs_iunpin
helpers and merge them into their only callers.  This also fixes up
various duplicate and/or incorrect comments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:56 -06:00
Christoph Hellwig 60ec678371 xfs: cleanup xfs_iunpin_wait/xfs_iunpin_nowait
Remove the inode item pointer and ili_last_lsn checks in
__xfs_iunpin_wait as any pinned inode is guaranteed to have them
valid.  After this the xfs_iunpin_nowait case is nothing more than a
xfs_log_force_lsn, as we know that the caller has already checked
the pincount.

Make xfs_iunpin_nowait the new low-level routine just doing the log
force and rewrite xfs_iunpin_wait around it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:50 -06:00
Christoph Hellwig d7658d487f xfs: kill xfs_lrw.h
Move the two declarations to better fitting headers now that
xfs_lrw.c is gone.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:44 -06:00
Christoph Hellwig d7e84f4137 xfs: factor common xfs_trans_bjoin code
Most of xfs_trans_bjoin is duplicated in xfs_trans_get_buf,
xfs_trans_getsb and xfs_trans_read_buf.  Add a new _xfs_trans_bjoin
which can be called by all four functions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:37 -06:00
Christoph Hellwig 35a8a72f06 xfs: stop passing opaque handles to xfs_log.c routines
Currenly we pass opaque xfs_log_ticket_t handles instead of
struct xlog_ticket pointers, and void pointers instead of
struct xlog_in_core pointers to various log manager functions.
Instead pass properly typed pointers after adding forward
declarations for them to xfs_log.h, and adjust the touched
function prototypes to the standard XFS style while at it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:32 -06:00
Christoph Hellwig c467c049e7 xfs: split xfs_bmap_btalloc
Split out the nullfb case into a separate function to reduce the stack
footprint and make the code more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:25 -06:00
Christoph Hellwig f7008d0aeb xfs: fix xfs_fsblock_t tracing
Using a static buffer in xfs_fmtfsblock means we can corrupt traces if
multiple CPUs hit this code path at the same.  Just remove xfs_fmtfsblock
for now and print the block number purely numerical.  If we want the
NULLFSBLOCK and NULLSTARTBLOCK formatting back the best way would be
a decoding plugin in the trace-cmd userspace command.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:17 -06:00
Christoph Hellwig 024910cbac xfs: fix inode pincount check in fsync
We need to hold the ilock to check the inode pincount safely.  While
we're at it also remove the check for ip->i_itemp->ili_last_lsn, a
pinned inode always has it set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:35:10 -06:00
Dave Chinner 77d7a0c2ee xfs: Non-blocking inode locking in IO completion
The introduction of barriers to loop devices has created a new IO
order completion dependency that XFS does not handle. The loop
device implements barriers using fsync and so turns a log IO in the
XFS filesystem on the loop device into a data IO in the backing
filesystem. That is, the completion of log IOs in the loop
filesystem are now dependent on completion of data IO in the backing
filesystem.

This can cause deadlocks when a flush daemon issues a log force with
an inode locked because the IO completion of IO on the inode is
blocked by the inode lock. This in turn prevents further data IO
completion from occuring on all XFS filesystems on that CPU (due to
the shared nature of the completion queues). This then prevents the
log IO from completing because the log is waiting for data IO
completion as well.

The fix for this new completion order dependency issue is to make
the IO completion inode locking non-blocking. If the inode lock
can't be grabbed, simply requeue the IO completion back to the work
queue so that it can be processed later. This prevents the
completion queue from being blocked and allows data IO completion on
other inodes to proceed, hence avoiding completion order dependent
deadlocks.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:52 -06:00
Christoph Hellwig 66d834ea60 xfs: implement optimized fdatasync
Allow us to track the difference between timestamp and size updates
by using mark_inode_dirty from the I/O completion code, and checking
the VFS inode flags in xfs_file_fsync.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:45 -06:00
Christoph Hellwig fd3200bef7 xfs: remove wrapper for the fsync file operation
Currently the fsync file operation is divided into a low-level
routine doing all the work and one that implements the Linux file
operation and does minimal argument wrapping.  This is a leftover
from the days of the vnode operations layer and can be removed to
simplify the code a bit, as well as preparing for the implementation
of an optimized fdatasync which needs to look at the Linux inode
state.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:38 -06:00
Christoph Hellwig 00258e36b2 xfs: remove wrappers for read/write file operations
Currently the aio_read, aio_write, splice_read and splice_write file
operations are divided into a low-level routine doing all the work
and one that implements the Linux file operations and does minimal
argument wrapping.  This is a leftover from the days of the vnode
operations layer and can be removed to simplify the code a lot.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:29 -06:00
Christoph Hellwig dda35b8f84 xfs: merge xfs_lrw.c into xfs_file.c
Currently the code to implement the file operations is split over
two small files.  Merge the content of xfs_lrw.c into xfs_file.c to
have it in one place.  Note that I haven't done various cleanups
that are possible after this yet, they will follow in the next
patch.  Also the function xfs_dev_is_read_only which was in
xfs_lrw.c before really doesn't fit in here at all and was moved to
xfs_mount.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:18 -06:00
Christoph Hellwig b262e5dfd9 xfs: fix dquota trace format
The be32_to_cpu in the TP_printk output breaks automatic parsing of
the trace format by the trace-cmd tools, so we have to move it into
the TP_assign block.  While we're at it also fix the format for the
quota limits to more regular and easier parseable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:34:11 -06:00
Eric Sandeen a9cc799eca xfs: increase readdir buffer size
While doing some testing of readdir perf a while back,
I noticed that the buffer size we're using internally is
smaller than what glibc gives us by default.  Upping this
size helped a bit, and seems safe.

glibc's __alloc_dir() does:

  const size_t default_allocation = (4 * BUFSIZ < sizeof (struct dirent64)
                                     ? sizeof (struct dirent64) : 4 * BUFSIZ);
  const size_t small_allocation = (BUFSIZ < sizeof (struct dirent64)
                                   ? sizeof (struct dirent64) : BUFSIZ);
  size_t allocation = default_allocation;
#ifdef _STATBUF_ST_BLKSIZE
  if (statp != NULL && default_allocation < statp->st_blksize)
    allocation = statp->st_blksize;
#endif

and

#define _G_BUFSIZ 8192
#define _IO_BUFSIZ _G_BUFSIZ
# define BUFSIZ _IO_BUFSIZ

so the default buffer is 4 * 8192 = 32768
(except in the unlikely case of blocks > 32k....)

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-03-01 16:33:41 -06:00
Linus Torvalds b305956abc Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (52 commits)
  fs/xfs: Correct NULL test
  xfs: optimize log flushing in xfs_fsync
  xfs: only clear the suid bit once in xfs_write
  xfs: kill xfs_bawrite
  xfs: log changed inodes instead of writing them synchronously
  xfs: remove invalid barrier optimization from xfs_fsync
  xfs: kill the unused XFS_QMOPT_* flush flags V2
  xfs: Use delay write promotion for dquot flushing
  xfs: Sort delayed write buffers before dispatch
  xfs: Don't issue buffer IO direct from AIL push V2
  xfs: Use delayed write for inodes rather than async V2
  xfs: Make inode reclaim states explicit
  xfs: more reserved blocks fixups
  xfs: turn off sign warnings
  xfs: don't hold onto reserved blocks on remount,ro
  xfs: quota limit statvfs available blocks
  xfs: replace KM_LARGE with explicit vmalloc use
  xfs: cleanup up xfs_log_force calling conventions
  xfs: kill XLOG_VEC_SET_TYPE
  xfs: remove duplicate buffer flags
  ...
2010-02-26 17:18:52 -08:00
Linus Torvalds f24407d2bd Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/xfs-vipt:
  xfs: fix xfs to work with Virtually Indexed architectures
  sh: add mm API for DMA to vmalloc/vmap areas
  arm: add mm API for DMA to vmalloc/vmap areas
  parisc: add mm API for DMA to vmalloc/vmap areas
  mm: add coherence API for DMA to vmalloc/vmap areas
2010-02-26 17:05:10 -08:00
Ben Myers 978ebd97d1 xfs_export_operations.commit_metadata
This is the commit_metadata export operation for XFS.

- Takes one inode to be committed.

- Forces the log up to the lsn of the inode.

- Doesn't force the log if the inode doesn't have a pincount.

Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
[bfields@citi.umich.edu: trivial whitespace fix]
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-02-20 13:14:50 -08:00
Tejun Heo 003cb608a2 percpu: add __percpu sparse annotations to fs
Add __percpu sparse annotations to fs.

These annotations are to make sparse consider percpu variables to be
in a different address space and warn if accessed without going
through percpu accessors.  This patch doesn't affect normal builds.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
2010-02-17 11:17:38 +09:00
Julia Lawall d67b1b0325 fs/xfs: Correct NULL test
Test the value that was just allocated rather than the previously tested one.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@r@
expression *x;
expression e;
identifier l;
@@

if (x == NULL || ...) {
    ... when forall
    return ...; }
... when != goto l;
    when != x = e
    when != &x
*x == NULL
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-13 13:22:53 -06:00
Christoph Hellwig 180040b89e xfs: optimize log flushing in xfs_fsync
If we have a pinned inode it must have a log item attached to it.
Usually that log item will have ili_last_lsn already set, in which
case we only need to flush the log up to that LSN instead of doing a
full log force.  This gives speedups of about 5% in some fsync heavy
workloads.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-12 13:45:14 -06:00
Christoph Hellwig 87185517de xfs: only clear the suid bit once in xfs_write
file_remove_suid already calls into ->setattr to clear the suid and
sgid bits if needed, no need to start a second transaction to do it
ourselves.

Note that xfs_write_clear_setuid issues a sync transaction while the
path through ->setattr doesn't, but that is consistant with the
other filesystems.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-12 13:43:57 -06:00
James Bottomley 73c77e2ccc xfs: fix xfs to work with Virtually Indexed architectures
xfs_buf.c includes what is essentially a hand rolled version of
blk_rq_map_kern().  In order to work properly with the vmalloc buffers
that xfs uses, this hand rolled routine must also implement the flushing
API for vmap/vmalloc areas.

[style updates from hch@lst.de]
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2010-02-05 12:32:35 -06:00
Dave Chinner 5322892d86 xfs: kill xfs_bawrite
There are no more users of this function left in the XFS code
now that we've switched everything to delayed write flushing.
Remove it.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-04 10:09:14 +11:00
Christoph Hellwig 07fec73625 xfs: log changed inodes instead of writing them synchronously
When an inode has already be flushed delayed write,
xfs_inode_clean() returns true and hence xfs_fs_write_inode() can
return on a synchronous inode write without having written the
inode. Currently these sycnhronous writes only come sync(1),
unmount, a sycnhronous NFS export and cachefiles so should be
relatively rare and out of common performance paths.

Realistically, a synchronous inode write is not necessary here; we
can avoid writing the inode by logging any non-transactional changes
that are pending.  This needs to be done with synchronous
transactions, but it avoids seeking between the log and inode
clusters as we do now. We don't force the log if the inode is
pinned, though, so this differs from the fsync case.  For normal
sys_sync and unmount behaviour this is fine because we do a
synchronous log force in xfs_sync_data which is called from the
->sync_fs code.

It does however break the NFS synchronous export guarantees for now,
but work is under way to fix this at a higher level or for the
higher level to provide an additional flag in the writeback control
to tell us that a log force is needed.

Portions of this patch are based on work from Dave Chinner.

Signed-off-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
2010-02-09 11:43:49 +11:00
Christoph Hellwig e8b217e753 xfs: remove invalid barrier optimization from xfs_fsync
We always need to flush the disk write cache and can't skip it just because
the no inode attributes have changed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
2010-02-02 10:16:26 +11:00
Dave Chinner 20026d9201 xfs: kill the unused XFS_QMOPT_* flush flags V2
dquots are never flushed asynchronously. Remove the flag and the
async write support from the flush function. Make the default flush
a delwri flush to make the inode flush code, which leaves the
XFS_QMOPT_SYNC the only flag remaining.  Convert that to use
SYNC_WAIT instead, just like the inode flush code.

V2:
- just pass flush flags straight through

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-04 09:48:58 +11:00
Dave Chinner 7d6a7bde52 xfs: Use delay write promotion for dquot flushing
xfs_qm_dqflock_pushbuf_wait() does a very similar trick to item
pushing used to do to flush out delayed write dquot buffers. Change
it to use the new promotion method rather than an async flush.

Also, xfs_qm_dqflock_pushbuf_wait() can return without the flush lock
held, yet the callers make the assumption that after this call the
flush lock is held. Always return with the flush lock held.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:13:41 +11:00
Dave Chinner 089716aa14 xfs: Sort delayed write buffers before dispatch
Currently when the xfsbufd writes delayed write buffers, it pushes
them to disk in the order they come off the delayed write list. If
there are lots of buffers ѕpread widely over the disk, this results
in overwhelming the elevator sort queues in the block layer and we
end up losing the posibility of merging adjacent buffers to minimise
the number of IOs.

Use the new generic list_sort function to sort the delwri dispatch
queue before issue to ensure that the buffers are pushed in the most
friendly order possible to the lower layers.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:13:25 +11:00
Dave Chinner d808f617ad xfs: Don't issue buffer IO direct from AIL push V2
All buffers logged into the AIL are marked as delayed write.
When the AIL needs to push the buffer out, it issues an async write of the
buffer. This means that IO patterns are dependent on the order of
buffers in the AIL.

Instead of flushing the buffer, promote the buffer in the delayed
write list so that the next time the xfsbufd is run the buffer will
be flushed by the xfsbufd. Return the state to the xfsaild that the
buffer was promoted so that the xfsaild knows that it needs to cause
the xfsbufd to run to flush the buffers that were promoted.

Using the xfsbufd for issuing the IO allows us to dispatch all
buffer IO from the one queue. This means that we can make much more
enlightened decisions on what order to flush buffers to disk as
we don't have multiple places issuing IO. Optimisations to xfsbufd
will be in a future patch.

Version 2
- kill XFS_ITEM_FLUSHING as it is now unused.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-02 10:13:42 +11:00
Dave Chinner c854363e80 xfs: Use delayed write for inodes rather than async V2
We currently do background inode flush asynchronously, resulting in
inodes being written in whatever order the background writeback
issues them. Not only that, there are also blocking and non-blocking
asynchronous inode flushes, depending on where the flush comes from.

This patch completely removes asynchronous inode writeback. It
removes all the strange writeback modes and replaces them with
either a synchronous flush or a non-blocking delayed write flush.
That is, inode flushes will only issue IO directly if they are
synchronous, and background flushing may do nothing if the operation
would block (e.g. on a pinned inode or buffer lock).

Delayed write flushes will now result in the inode buffer sitting in
the delwri queue of the buffer cache to be flushed by either an AIL
push or by the xfsbufd timing out the buffer. This will allow
accumulation of dirty inode buffers in memory and allow optimisation
of inode cluster writeback at the xfsbufd level where we have much
greater queue depths than the block layer elevators. We will also
get adjacent inode cluster buffer IO merging for free when a later
patch in the series allows sorting of the delayed write buffers
before dispatch.

This effectively means that any inode that is written back by
background writeback will be seen as flush locked during AIL
pushing, and will result in the buffers being pushed from there.
This writeback path is currently non-optimal, but the next patch
in the series will fix that problem.

A side effect of this delayed write mechanism is that background
inode reclaim will no longer directly flush inodes, nor can it wait
on the flush lock. The result is that inode reclaim must leave the
inode in the reclaimable state until it is clean. Hence attempts to
reclaim a dirty inode in the background will simply skip the inode
until it is clean and this allows other mechanisms (i.e. xfsbufd) to
do more optimal writeback of the dirty buffers. As a result, the
inode reclaim code has been rewritten so that it no longer relies on
the ambiguous return values of xfs_iflush() to determine whether it
is safe to reclaim an inode.

Portions of this patch are derived from patches by Christoph
Hellwig.

Version 2:
- cleanup reclaim code as suggested by Christoph
- log background reclaim inode flush errors
- just pass sync flags to xfs_iflush

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-06 12:39:36 +11:00
Dave Chinner 777df5afdb xfs: Make inode reclaim states explicit
A.K.A.: don't rely on xfs_iflush() return value in reclaim

We have gradually been moving checks out of the reclaim code because
they are duplicated in xfs_iflush(). We've had a history of problems
in this area, and many of them stem from the overloading of the
return values from xfs_iflush() and interaction with inode flush
locking to determine if the inode is safe to reclaim.

With the desire to move to delayed write flushing of inodes and
non-blocking inode tree reclaim walks, the overloading of the
return value of xfs_iflush makes it very difficult to determine
the correct thing to do next.

This patch explicitly re-adds the checks to the inode reclaim code,
removing the reliance on the return value of xfs_iflush() to
determine what to do next. It also means that we can clearly
document all the inode states that reclaim must handle and hence
we can easily see that we handled all the necessary cases.

This also removes the need for the xfs_inode_clean() check in
xfs_iflush() as all callers now check this first (safely).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-02-06 12:37:26 +11:00
Eric Sandeen d5db0f97fb xfs: more reserved blocks fixups
This mangles the reserved blocks counts a little more.

1) add a helper function for the default reserved count
2) add helper functions to save/restore counts on ro/rw
3) save/restore reserved blocks on freeze/thaw
4) disallow changing reserved count while readonly

V2: changed field name to match Dave's changes

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-02-08 17:41:48 -06:00
Dave Chinner 388f1f0c34 xfs: turn off sign warnings
Because they cause warnings in static inline functions conditionally
compiled into XFS from the VFS (e.g. fsnotify).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:10:15 +11:00
Dave Chinner cbe132a8bd xfs: don't hold onto reserved blocks on remount,ro
If we hold onto reserved blocks when doing a remount,ro we end
up writing the blocks used count to disk that includes the reserved
blocks. Reserved blocks are not actually used, so this results in
the values in the superblock being incorrect.

Hence if we run xfs_check or xfs_repair -n while the filesystem is
mounted remount,ro we end up with an inconsistent filesystem being
reported. Also, running xfs_copy on the remount,ro filesystem will
result in an inconsistent image being generated.

To fix this, unreserve the blocks when doing the remount,ro, and
reserved them again on remount,rw. This way a remount,ro filesystem
will appear consistent on disk to all utilities.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-26 15:08:49 +11:00
Christoph Hellwig 9b00f30762 xfs: quota limit statvfs available blocks
A "df" run on an NFS client of an exported XFS file system reports
the wrong information for "available" blocks.  When a block quota is
enforced, the amount reported as free is limited by the quota, but
the amount reported available is not (and should be).

Reported-by: Guk-Bong, Kwon <gbkwon@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 16:34:23 -06:00
Christoph Hellwig bdfb04301f xfs: replace KM_LARGE with explicit vmalloc use
We use the KM_LARGE flag to make kmem_alloc and friends use vmalloc
if necessary.  As we only need this for a few boot/mount time
allocations just switch to explicit vmalloc calls there.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:56 -06:00
Christoph Hellwig a14a348bff xfs: cleanup up xfs_log_force calling conventions
Remove the XFS_LOG_FORCE argument which was always set, and the
XFS_LOG_URGE define, which was never used.

Split xfs_log_force into a two helpers - xfs_log_force which forces
the whole log, and xfs_log_force_lsn which forces up to the
specified LSN.  The underlying implementations already were entirely
separate, as were the users.

Also re-indent the new _xfs_log_force/_xfs_log_force which
previously had a weird coding style.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:49 -06:00
Christoph Hellwig 4139b3b337 xfs: kill XLOG_VEC_SET_TYPE
This macro only obsfucates the log item type assignments, so kill it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:43 -06:00
Christoph Hellwig 0cadda1c5f xfs: remove duplicate buffer flags
Currently we define aliases for the buffer flags in various
namespaces, which only adds confusion.  Remove all but the XBF_
flags to clean this up a bit.

Note that we still abuse XFS_B_ASYNC/XBF_ASYNC for some non-buffer
uses, but I'll clean that up later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:36 -06:00
Christoph Hellwig a210c1aa7f xfs: implement quota warnings via netlink
Wire up quota_send_warning to send quota warnings over netlink.
This is used by various desktops to show user quota warnings.

Tested by running the quota_nld daemon while running the xfstest
quota tests and observing the warnings.  I'll see how I can get a
more formal testcase for it written.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:28 -06:00
Christoph Hellwig 4d1f88d75b xfs: clean up error handling in xfs_trans_dqresv
Move the error code selection after the goto label and fold the
xfs_quota_error helper into it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:22 -06:00
Christoph Hellwig 512dd1abd9 xfs: kill XFS_QMOPT_ASYNC
The option is unused and one of the few remaining users of
xfs_bawrite, so let's get rid of it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-21 13:44:10 -06:00
Dave Chinner 587aa0feb7 xfs: rearrange xfs_mod_sb() to avoid array subscript warning
gcc warns of an array subscript out of bounds in xfs_mod_sb().
The code is written in such a way that if the array subscript is
out of bounds, then it will assert fail. Rearrange the code to
avoid the bounds check warning.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 12:04:53 +11:00
Dave Chinner f0a0eaa8da xfs: suppress spurious uninitialised var warning in xfs_bmapi()
Initialise the xfs_bmalloca_t structure to zero to avoid uninitialised
variable warnings. This is done by zeroing the arg structure rather than
using the uninitialised_var() trick so we know for certain that the
structure is correctly initialised as xfs_bmapi is a very complex
function and it is difficult to prove warnings are spurious.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:50:06 +11:00
Dave Chinner 58c75cfb51 xfs: make compile warn about char sign mismatches again
The -fno-unsigned-char directive has no effect anymore as the
XFs build is clean. However, the kernel build hides pointer sign
differences so turn that back on so that we can clean up all the
mismatches prior to a userspace code resync.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:49:18 +11:00
Dave Chinner 4a24cb7140 xfs: clean up sign warnings in dir2 code
We are now consistently using unsigned char strings for names
so fix up the remaining warnings in the dir2 code to complete
the cleanup.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:48:05 +11:00
Dave Chinner a9273ca5c6 xfs: convert attr to use unsigned names
To be consistent with the directory code, the attr code should use
unsigned names. Convert the names from the vfs at the highest level
to unsigned, and ænsure they are consistenly used as unsigned down
to disk.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:48 +11:00
Dave Chinner b9c4864957 xfs: xfs_buf_iomove() doesn't care about signedness
xfs_buf_iomove() uses xfs_caddr_t as it's parameter types, but it doesn't
care about the signedness of the variables as it is just copying the
data. Change the prototype to use void * so that we don't get sign
warnings at call sites.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:39 +11:00
Dave Chinner a3380ae39f xfs: make xfs_dir_cilookup_result use unsigned char
For consistency with the result of the code.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:25 +11:00
Dave Chinner 2bc754213d xfs: convert dirnameops to unsigned char names
To be consistent across the codebase, convert the dirnameops to pass
the directory names by unsigned char strings.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:17 +11:00
Dave Chinner 046ea75313 xfs: convert DM ops to use unsigned char names
dmops uses a signed char for it's namespace event. To be consistent
with the rest of the code, convert them to unsigned char for the
namespace string.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:47:08 +11:00
Dave Chinner e2bcd936eb xfs: directory names are unsigned
Convert the struct xfs_name to use unsigned chars for the name
strings to match both what is stored on disk (__uint8_t) and what
the VFS expects (unsigned char).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-01-20 10:44:58 +11:00
Christoph Hellwig 4e23471a3f xfs: move more buffer helpers into xfs_buf.c
Move xfsbdstrat and xfs_bdstrat_cb from xfs_lrw.c and xfs_bioerror
and xfs_bioerror_relse from xfs_rw.c into xfs_buf.c.  This also
means xfs_bioerror and xfs_bioerror_relse can be marked static now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:35:17 -06:00
Christoph Hellwig 64e0bc7d2a xfs: clean up xfs_bwrite
Fold XFS_bwrite into it's only caller, xfs_bwrite and move it into
xfs_buf.c instead of leaving it as a fairly large inline function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:35:07 -06:00
Christoph Hellwig 873ff5501d xfs: clean up log buffer writes
Don't bother using XFS_bwrite as it doesn't provide much code for
our use case.  Instead opencode it and fold xlog_bdstrat_cb into the
new xlog_bdstrat helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:54 -06:00
Dave Chinner e57336ff7f xfs: embed the pagb_list array in the perag structure
Now that the perag structure is allocated memory rather than held in
an array, we don't need to have the busy extent array external to
the structure. Embed it into the perag structure to avoid needing an
extra allocation when setting up.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:39 -06:00
Dave Chinner 8b26c5825e xfs: handle ENOMEM correctly during initialisation of perag structures
Add proper error handling in case an error occurs while initializing
new perag structures for a mount point.  The mount structure is
restored to its previous state by deleting and freeing any perag
structures added during the call.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:30 -06:00
Dave Chinner b657fc82a3 xfs: Kill filestreams cache flush
The filestreams cache flush is not needed in the sync code as it
does not affect data writeback, and it is now not used by the growfs
code, either, so kill it.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:22 -06:00
Dave Chinner 0fa800fbd5 xfs: Add trace points for per-ag refcount debugging.
Uninline xfs_perag_{get,put} so that tracepoints can be inserted
into them to speed debugging of reference count problems.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:12 -06:00
Dave Chinner aed3bb90ab xfs: Reference count per-ag structures
Reference count the per-ag structures to ensure that we keep get/put
pairs balanced. Assert that the reference counts are zero at unmount
time to catch leaks. In future, reference counts will enable us to
safely remove perag structures by allowing us to detect when they
are no longer in use.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:34:04 -06:00
Dave Chinner 1c1c6ebcf5 xfs: Replace per-ag array with a radix tree
The use of an array for the per-ag structures requires reallocation
of the array when growing the filesystem. This requires locking
access to the array to avoid use after free situations, and the
locking is difficult to get right. To avoid needing to reallocate an
array, change the per-ag structures to an allocated object per ag
and index them using a tree structure.

The AGs are always densely indexed (hence the use of an array), but
the number supported is 2^32 and lookups tend to be random and hence
indexing needs to scale. A simple choice is a radix tree - it works
well with this sort of index.  This change also removes another
large contiguous allocation from the mount/growfs path in XFS.

The growing process now needs to change to only initialise the new
AGs required for the extra space, and as such only needs to
exclusively lock the tree for inserts. The rest of the code only
needs to lock the tree while doing lookups, and hence this will
remove all the deadlocks that currently occur on the m_perag_lock as
it is now an innermost lock. The lock is also changed to a spinlock
from a read/write lock as the hold time is now extremely short.

To complete the picture, the per-ag structures will need to be
reference counted to ensure that we don't free/modify them while
they are still in use.  This will be done in subsequent patch.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:52 -06:00
Dave Chinner 44b56e0a1a xfs: convert remaining direct references to m_perag
Convert the remaining direct lookups of the per ag structures to use
get/put accesses. Ensure that the loops across AGs and prior users
of the interface balance gets and puts correctly.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:39 -06:00
Dave Chinner 4196ac08c0 xfs: Convert filestreams code to use per-ag get/put routines
Use xfs_perag_get() and xfs_perag_put() in the filestreams code.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:22 -06:00
Dave Chinner a862e0fdcb xfs: Don't directly reference m_perag in allocation code
Start abstracting the perag references so that the indexing of the
structures is not directly coded into all the places that uses the
perag structures. This will allow us to separate the use of the
perag structure and the way it is indexed and hence avoid the known
deadlocks related to growing a busy filesystem.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:12 -06:00
Dave Chinner 5017e97d52 xfs: rename xfs_get_perag
xfs_get_perag is really getting the perag that an inode belongs to
based on it's inode number. Convert the use of this function to just
get the perag from a provided ag number.  Use this new function to
obtain the per-ag structure when traversing the per AG inode trees
for sync and reclaim.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:33:02 -06:00
Dave Chinner c9c129714e xfs: Don't wake xfsbufd when idle
The xfsbufd wakes every xfsbufd_centisecs (once per second by
default) for each filesystem even when the filesystem is idle.  If
the xfsbufd has nothing to do, put it into a long term sleep and
only wake it up when there is work pending (i.e. dirty buffers to
flush soon). This will make laptop power misers happy.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:32:54 -06:00
Dave Chinner 453eac8a9a xfs: Don't wake the aild once per second
Now that the AIL push algorithm is traversal safe, we don't need a
watchdog function in the xfsaild to catch pushes that fail to make
progress. Remove the watchdog timeout and make pushes purely driven
by demand. This will remove the once-per-second wakeup that is seen
when the filesystem is idle and make laptop power misers happy.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:32:46 -06:00
Dave Chinner f0a7695380 xfs: Use list_heads for log recovery item lists
Remove the roll-your-own linked list operations.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:31:51 -06:00
Eric Sandeen 5d77c0dc0c xfs: make several more functions static
Just minor housekeeping, a lot more functions can be trivially made
static; others could if we reordered things a bit...

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:31:38 -06:00
Dave Chinner 6bded0f383 xfs: clean up inconsistent variable naming in xfs_swap_extent
The swap extent ioctl passes in a target inode and a temporary inode
which are clearly named in the ioctl structure. The code then
assigns temp to target and vice versa, making it extremely difficult
to work out which inode is which later in the code.  Make this
consistent throughout the code.

Also make xfs_swap_extent static as there are no external users of
the function.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:31:23 -06:00
Dave Chinner 3a85cd96d3 xfs: add tracing to xfs_swap_extents
To be able to diagnose whether the swap extents function is
detecting compatible inode data fork configurations for swapping
extents, add tracing points to the code to allow us to see the
format of the inode forks before and after the swap.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 15:20:06 -06:00
Dave Chinner e09f98606d xfs: xfs_swap_extents needs to handle dynamic fork offsets
When swapping extents, we can corrupt inodes by swapping data forks
that are in incompatible formats.  This is caused by the two indoes
having different fork offsets due to the presence of an attribute
fork on an attr2 filesystem.  xfs_fsr tries to be smart about
setting the fork offset, but the trick it plays only works on attr1
(old fixed format attribute fork) filesystems.

Changing the way xfs_fsr sets up the attribute fork will prevent
this situation from ever occurring, so in the kernel code we can get
by with a preventative fix - check that the data fork in the
defragmented inode is in a format valid for the inode it is being
swapped into.  This will lead to files that will silently and
potentially repeatedly fail defragmentation, so issue a warning to
the log when this particular failure occurs to let us know that
xfs_fsr needs updating/fixing.

To help identify how to improve xfs_fsr to avoid this issue, add
trace points for the inodes being swapped so that we can determine
why the swap was rejected and to confirm that the code is making the
right decisions and modifications when swapping forks.

A further complication is even when the swap is allowed to proceed
when the fork offset is different between the two inodes then value
for the maximum number of extents the data fork can hold can be
wrong. Make sure these are also set correctly after the swap occurs.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:49:07 -06:00
Dave Chinner 3daeb42c13 xfs: fix missing error check in xfs_rtfree_range
When xfs_rtfind_forw() returns an error, the block is returned
uninitialised.  xfs_rtfree_range() is not checking the error return,
so could be using an uninitialised block number for modifying bitmap
summary info.

The problem was found by gcc when compiling the *userspace* libxfs
code - it is an copy of the kernel code with the exact same bug.
gcc gives an uninitialised variable warning on the userspace code
but not on the kernel code. You gotta love the consistency (Mmmm,
slightly chewy today!).

Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:46:19 -06:00
Dave Chinner 4b6a46882c xfs: fix stale inode flush avoidance
When reclaiming stale inodes, we need to guarantee that inodes are
unpinned before returning with a "clean" status. If we don't we can
reclaim inodes that are pinned, leading to use after free in the
transaction subsystem as transactions complete.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:46:02 -06:00
Dave Chinner 126976c7c1 xfs: Remove inode iolock held check during allocation
lockdep complains about a the lock not being initialised as we do an
ASSERT based check that the lock is not held before we initialise it
to catch inodes freed with the lock held.

lockdep does this check for us in the lock initialisation code, so
remove the ASSERT to stop the lockdep warning.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:45:33 -06:00
Dave Chinner 57817c6822 xfs: reclaim all inodes by background tree walks
We cannot do direct inode reclaim without taking the flush lock to
ensure that we do not reclaim an inode under IO. We check the inode
is clean before doing direct reclaim, but this is not good enough
because the inode flush code marks the inode clean once it has
copied the in-core dirty state to the backing buffer.

It is the flush lock that determines whether the inode is still
under IO, even though it is marked clean, and the inode is still
required at IO completion so we can't reclaim it even though it is
clean in core. Hence the requirement that we need to take the flush
lock even on clean inodes because this guarantees that the inode
writeback IO has completed and it is safe to reclaim the inode.

With delayed write inode flushing, we coul dend up waiting a long
time on the flush lock even for a clean inode. The background
reclaim already handles this efficiently, so avoid all the problems
by killing the direct reclaim path altogether.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:44:44 -06:00
Dave Chinner 018027be90 xfs: Avoid inodes in reclaim when flushing from inode cache
The reclaim code will handle flushing of dirty inodes before reclaim
occurs, so avoid them when determining whether an inode is a
candidate for flushing to disk when walking the radix trees.  This
is based on a test patch from Christoph Hellwig.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:44:21 -06:00
Dave Chinner c8e20be020 xfs: reclaim inodes under a write lock
Make the inode tree reclaim walk exclusive to avoid races with
concurrent sync walkers and lookups. This is a version of a patch
posted by Christoph Hellwig that avoids all the code duplication.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
2010-01-15 13:43:55 -06:00