The locking in xfs_iget_cache_hit currently has numerous problems:
- we clear the reclaim tag without i_flags_lock which protects
modifications to it
- we call inode_init_always which can sleep with pag_ici_lock
held (this is oss.sgi.com BZ #819)
- we acquire and drop i_flags_lock a lot and thus provide no
consistency between the various flags we set/clear under it
This patch fixes all that with a major revamp of the locking in
the function. The new version acquires i_flags_lock early and
only drops it once we need to call into inode_init_always or before
calling xfs_ilock.
This patch fixes a bug seen in the wild where we race modifying the
reclaim tag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Felix Blyakher <felixb@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
SYNC_BDFLUSH is a leftover from IRIX and rather misnamed for todays
code. Make xfs_sync_fsdata and xfs_dq_sync use the SYNC_TRYLOCK flag
for not blocking on logs just as the inode sync code already does.
For xfs_sync_fsdata it's a trivial 1:1 replacement, but for xfs_qm_sync
I use the opportunity to decouple the non-blocking lock case from the
different flushing modes, similar to the inode sync code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
We want to wait for all I/O to finish when we do data integrity syncs. So
there is no reason to keep SYNC_WAIT separate from SYNC_IOWAIT. This
causes a little change in behaviour for the ENOSPC flushing code which now
does a second submission and wait of buffered I/O, but that should finish
ASAP as we already did an asynchronous writeout earlier.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
xfs_sync_inodes is used to write back either file data or inode metadata.
In general we always do these separately, except for one fishy case in
xfs_fs_put_super that does both. So separate xfs_sync_inodes into
separate xfs_sync_data and xfs_sync_attr functions. In xfs_fs_put_super
we first call the data sync and then the attr sync as that was the previous
order. The moved log force in that path doesn't make a difference because
we will force the log again as part of the real unmount process.
The filesystem readonly checks are not performed by the new function but
instead moved into the callers, given that most callers alredy have it
further up in the stack. Also add debug checks that we do not pass in
incorrect flags in the new xfs_sync_data and xfs_sync_attr function and
fix the one place that did pass in a wrong flag.
Also remove a comment mentioning xfs_sync_inodes that has been incorrect
for a while because we always take either the iolock or ilock in the
sync path these days.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Use xfs_inode_ag_iterator instead of opencoding the inode walk in the
quota code. Mark xfs_inode_ag_iterator and xfs_sync_inode_valid non-static
to allow using them from the quota code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Given that we walk across the per-ag inode lists so often, it makes sense to
introduce an iterator for this.
Convert the sync and reclaim code to use this new iterator, quota code will
follow in the next patch.
Also change xfs_reclaim_inode to return -EGAIN instead of 1 for an inode
already under reclaim. This simplifies the AG iterator and doesn't
matter for the only other caller.
[hch: merged the lookup and execute callbacks back into one to get the
pag_ici_lock locking correct and simplify the code flow]
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
The noblock parameter of xfs_reclaim_inodes is only ever set to zero. Remove
it and all the conditional code that is never executed.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Separate the validation of inodes found by the radix
tree walk from the radix tree lookup.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
In many cases we only want to sync inode metadata. Split out the inode
flushing into a separate helper to prepare factoring the inode sync code.
Based on a patch from Dave Chinner, but redone to keep the current behaviour
exactly and leave changes to the flushing logic to another patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
In many cases we only want to sync inode data. Start spliting the inode sync
into data sync and inode sync by factoring out the inode data flush.
[hch: minor cleanups]
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Kill the quota ops function vector and replace it with direct calls or
stubs in the CONFIG_XFS_QUOTA=n case.
Make sure we check XFS_IS_QUOTA_RUNNING in the right spots. We can remove
the number of those checks because the XFS_TRANS_DQ_DIRTY flag can't be set
otherwise.
This brings us back closer to the way this code worked in IRIX and earlier
Linux versions, but we keep a lot of the more useful factoring of common
code.
Eventually we should also kill xfs_qm_bhv.c, but that's left for a later
patch.
Reduces the size of the source code by about 250 lines and the size of
XFS module by about 1.5 kilobytes with quotas enabled:
text data bss dec hex filename
615957 2960 3848 622765 980ad fs/xfs/xfs.o
617231 3152 3848 624231 98667 fs/xfs/xfs.o.old
Fallout:
- xfs_qm_dqattach is split into xfs_qm_dqattach_locked which expects
the inode locked and xfs_qm_dqattach which does the locking around it,
thus removing XFS_QMOPT_ILOCKED.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
xfs_flush_inodes() currently uses a magic timeout to wait for
some inodes to be flushed before returning. This isn't
really reliable but used to be the best that could be done
due to deadlock potential of waiting for the entire flush.
Now the inode flush is safe to execute while we hold page
and inode locks, we can wait for all the inodes to flush
synchronously. Convert the wait mechanism to a completion
to do this efficiently. This should remove all remaining
spurious ENOSPC errors from the delayed allocation reservation
path.
This is extracted almost line for line from a larger patch
from Mikulas Patocka.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we are writing to a single file and hit ENOSPC, we trigger a background
flush of the inode and try again. Because we hold page locks and the iolock,
the flush won't proceed until after we release these locks. This occurs once
we've given up and ENOSPC has been reported. Hence if this one is the only
dirty inode in the system, we'll get an ENOSPC prematurely.
To fix this, remove the async flush from the allocation routines and move
it to the top of the write path where we can do a synchronous flush
and retry the write again. Only retry once as a second ENOSPC indicates
that we really are ENOSPC.
This avoids a page cache deadlock when trying to do this flush synchronously
in the allocation layer that was identified by Mikulas Patocka.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently xfs_device_flush calls sync_blockdev() which is
a no-op for XFS as all it's metadata is held in a different
address to the one sync_blockdev() works on.
Call xfs_sync_inodes() instead to flush all the delayed
allocation blocks out. To do this as efficiently as possible,
do it via two passes - one to do an async flush of all the
dirty blocks and a second to wait for all the IO to complete.
This requires some modification to the xfs-sync_inodes_ag()
flush code to do efficiently.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Till VFS can correctly support read-only remount without racing,
use WARN_ON instead of BUG_ON on detecting transaction in flight
after quiescing filesystem.
Signed-off-by: Felix Blyakher <felixb@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Hit this assert because an inode was tagged with XFS_ICI_RECLAIM_TAG but
not XFS_IRECLAIMABLE|XFS_IRECLAIM. This is because xfs_iget_cache_hit()
first clears XFS_IRECLAIMABLE and then calls __xfs_inode_clear_reclaim_tag()
while only holding the pag_ici_lock in read mode so we can race with
xfs_reclaim_inodes_ag(). Looks like xfs_reclaim_inodes_ag() will do the
right thing anyway so just remove the assert.
Thanks to Christoph for pointing out where the problem was.
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
The whole machinery to wait on I/O completion is related to the I/O path
and should be there instead of in xfs_vnode.c. Also give the functions
more descriptive names.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
The radix tree walks in xfs_sync_inodes_ag and xfs_qm_dqrele_all_inodes()
can find inodes that are still undergoing initialisation. Avoid
them by checking for the the XFS_INEW() flag once we have a reference
on the inode. This flag is cleared once the inode is properly initialised.
SGI-PV: 987246
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
If we are syncing data in xfs_sync_inodes_ag(), the VFS inode must still
be referencable as the dirty data state is carried on the VFS inode. hence
if we can't get a reference via igrab(), the inode must be in reclaim
which implies that it has no dirty data attached.
Leave such inodes to the reclaim code to flush the dirty inode state to
disk and so avoid attempting to access the VFS inode when it may not exist
in xfs_sync_inodes_ag().
Version 4:
o don't reference linux inode until after igrab() succeeds
Version 3:
o converted unlock/rele to an xfs_iput() call.
Version 2:
o change igrab logic to be more linear
o remove initial reclaimable inode check now that we are using
igrab() failure to find reclaimable inodes
o assert that igrab failure occurs only on reclaimable inodes
o clean up inode locking - only grab the iolock if we are doing
a SYNC_DELWRI call and we have a dirty inode.
SGI-PV: 987246
SGI-Modid: xfs-linux-melb:xfs-kern:32391a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Peter Leckie <pleckie@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
If the last block of the AG has inodes in it and the AG is an exactly
power-of-2 size then the last inode in the AG points to the last block in
the AG. If we try to find the next inode in the AG by adding one to the
inode number, we increment the inode number past the size of the AG. The
result is that the macro XFS_INO_TO_AGINO() will strip the AG portion of
the inode number and return an inode number of zero.
That is, instead of terminating the lookup loop because we hit the inode
number went outside the valid range for the AG, the search index returns
to zero and we start traversing the radix tree from the start again. This
results in an endless loop in xfs_sync_inodes_ag().
Fix it be detecting if the new search index decreases as a result of
incrementing the current inode number. That indicate an overflow and hence
that we have finished processing the AG so we can terminate the loop.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32335a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Now that the deleted inodes list is unused, kill it. This also removes the
i_reclaim list head from the xfs_inode, shrinking it by two pointers.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32334a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Use the reclaim tag to walk the radix tree and find the inodes under
reclaim. This was the only user of the deleted inode list.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32333a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Prepare for removing the deleted inode list by marking inodes for reclaim
in the inode radix trees so that we can use the radix trees to find
reclaimable inodes.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32331a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
The function names xfs_finish_reclaim and xfs_finish_reclaim_all are not
very descriptive of what they are reclaiming. Rename to
xfs_reclaim_inode[s] to match the xfs_sync_inodes() function.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32330a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Background inode reclaim is run by the xfssyncd. Move the reclaim worker
functions to be close to the sync code as the are very similar in
structure and are both run from the same background thread.
SGI-PV: 988142
SGI-Modid: xfs-linux-melb:xfs-kern:32329a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
With all the other filesystem sync code it in xfs_sync.c including the
data quiesce code, it makes sense to move the remaining quiesce code to
the same place.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32312a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
There are no more callers to xfs_sync() now, so remove the function
altogther.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32311a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
SYNC_CLOSE is only ever used and checked in conjunction with SYNC_WAIT,
and this only done in one spot. The only thing this does is make
XFS_bflush() calls to the data buftargs.
This will happen very shortly afterwards the xfs_sync() call anyway in the
unmount path via the xfs_close_devices(), so this code is redundant and
can be removed. That only user of SYNC_CLOSE is now gone, so kill the flag
completely.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32310a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Continue to de-multiplex xfs_sync be replacing all SYNC_DELWRI callers
with direct calls functions that do the work. Isolate the data quiesce
case to a function in xfs_sync.c. Isolate the FSDATA case with explicit
calls to xfs_sync_fsdata().
Version 2: o Push delwri related log forces into xfs_sync_inodes().
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32309a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Continue to de-multiplex xfs_sync be replacing all SYNC_ATTR callers with
direct calls xfs_sync_inodes(). Add an assert into xfs_sync() to ensure we
caught all the SYNC_ATTR callers.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32308a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Start de-multiplexing xfs_sync() by making xfs_sync_worker() call the
specific sync functions it needs. This is only a small, unique subset of
the entire xfs_sync() code so is easier to follow.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32307a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Now that the only caller is xfs_sync(), merge the two together as it makes
no sense to keep them separate.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32306a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Kill the unused arg in xfs_syncsub() and xfs_sync_inodes(). For callers of
xfs_syncsub() that only want to flush inodes, replace xfs_syncsub() with
direct calls to xfs_sync_inodes() as that is all that is being done with
the specific flags being passed in.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32305a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
With the sync code relocated to the linux-2.6 directory we can use struct
inodes directly. If we do the same thing for the quota release code, we
can remove vn_grab altogether. While here, convert the VN_BAD() checks to
is_bad_inode() so we can remove vnodes entirely from this code.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32304a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Split out two helpers from xfs_syncsub for the dummy log commit and the
superblock writeout.
SGI-PV: 988140
SGI-Modid: xfs-linux-melb:xfs-kern:32303a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Update xfs_sync_inodes to walk the inode radix tree cache to find dirty
inodes. This removes a huge bunch of nasty, messy code for traversing the
mount inode list safely and removes another user of the mount inode list.
Version 3 o rediff against new linux-2.6/xfs_sync.c code
Version 2 o add comment explaining use of gang lookups for a single inode
o use IRELE, not VN_RELE o move check for ag initialisation to caller.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32290a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
xfs_iflush_all() walks the m_inodes list to find inodes that need
reclaiming. We already have such a list - the m_del_inodes list. Replace
xfs_iflush_all() with a call to xfs_finish_reclaim_all() and clean up
xfs_finish_reclaim_all() to handle the different flush modes now needed.
Originally based on a patch from Christoph Hellwig.
Version 3 o rediff against new linux-2.6/xfs_sync.c code
Version 2 o revert xfs_syncsub() inode reclaim behaviour back to original
code o xfs_quiesce_fs() should use XFS_IFLUSH_DELWRI_ELSE_ASYNC, not
XFS_IFLUSH_ASYNC, to prevent change of behaviour.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32284a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Move all the xfssyncd code to the new xfs_sync.c file. This places it
closer to the actual code that it interacts with, rather than just being
associated with high level VFS code.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32283a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
The sync code in XFS is spread around several files. While it used to make
sense to have such a distribution, the code is about to be cleaned up and
so centralising it in one spot as the first step makes sense.
SGI-PV: 988139
SGI-Modid: xfs-linux-melb:xfs-kern:32282a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
