During mount we establish references to the RT inodes, which we keep for
the lifetime of the filesystem. Instead of using xfs_trans_iget to grab
additional references when adding RT inodes to transactions use the
combination of xfs_ilock and xfs_trans_ijoin_ref, which archives the same
end result with less overhead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Right now we, are relying on the fact that when we attempt to
actually do the discard, blkdev_issue_discar() returns -EOPNOTSUPP
and the user is informed that the device does not support discard.
However, in the case where the we do not hit any suitable free
extent to trim in FITRIM code, it will finish without any error.
This is very confusing, because it seems that FITRIM was successful
even though the device does not actually supports discard.
Solution: Check for the discard support before attempt to search for
free extents.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
The FSGEOMETRY_V1 ioctl (and its compat equivalent) calls out to
xfs_fs_geometry() with a version number of 3. This code path does not
fill in the logsunit member of the passed xfs_fsop_geom_t, leading to
the leaking of four bytes of uninitialized stack data to potentially
unprivileged callers.
v2 switches to memset() to avoid future issues if structure members
change, on suggestion of Dave Chinner.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Reviewed-by: Eugene Teo <eugeneteo@kernel.org>
Signed-off-by: Alex Elder <aelder@sgi.com>
Right now we, are relying on the fact that when we attempt to
actually do the discard, blkdev_issue_discar() returns -EOPNOTSUPP
and the user is informed that the device does not support discard.
However, in the case where the we do not hit any suitable free
extent to trim in FITRIM code, it will finish without any error.
This is very confusing, because it seems that FITRIM was successful
even though the device does not actually supports discard.
Solution: Check for the discard support before attempt to search for
free extents.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
The FSGEOMETRY_V1 ioctl (and its compat equivalent) calls out to
xfs_fs_geometry() with a version number of 3. This code path does not
fill in the logsunit member of the passed xfs_fsop_geom_t, leading to
the leaking of four bytes of uninitialized stack data to potentially
unprivileged callers.
v2 switches to memset() to avoid future issues if structure members
change, on suggestion of Dave Chinner.
Signed-off-by: Dan Rosenberg <drosenberg@vsecurity.com>
Reviewed-by: Eugene Teo <eugeneteo@kernel.org>
Signed-off-by: Alex Elder <aelder@sgi.com>
The rt bitmap and summary inodes do not participate in the normal inode
locking protocol. Instead the rt bitmap inode can be locked in any
transaction involving rt allocations, and the both of the rt inodes can
be locked at the same time. Add specific lockdep subclasses for the rt
inodes to prevent lockdep from blowing up.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We can easily set the extsize flag without setting an extent size
hint, or one that evaluates to zero. Historically the di_extsize
field was only used when it was non-zero, but the commit
"Cleanup inode extent size hint extraction"
broke this. Restore the old behaviour, thus fixing xfsqa 090 with
a debug kernel.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Currently both xfs_rtpick_extent and xfs_rtallocate_extent call
xfs_trans_iget to grab and lock the rt bitmap inode, which results in a
deadlock since the removal of the lock recursion counters in commit
"xfs: simplify inode to transaction joining"
Fix this by acquiring and locking the inode in xfs_bmap_rtalloc before
calling into xfs_rtpick_extent and xfs_rtallocate_extent.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
SELinux would like to implement a new labeling behavior of newly created
inodes. We currently label new inodes based on the parent and the creating
process. This new behavior would also take into account the name of the
new object when deciding the new label. This is not the (supposed) full path,
just the last component of the path.
This is very useful because creating /etc/shadow is different than creating
/etc/passwd but the kernel hooks are unable to differentiate these
operations. We currently require that userspace realize it is doing some
difficult operation like that and than userspace jumps through SELinux hoops
to get things set up correctly. This patch does not implement new
behavior, that is obviously contained in a seperate SELinux patch, but it
does pass the needed name down to the correct LSM hook. If no such name
exists it is fine to pass NULL.
Signed-off-by: Eric Paris <eparis@redhat.com>
Convert from create[_singlethread]_workqueue() to alloc_workqueue().
* xfsdatad_workqueue and xfsconvertd_workqueue are identity converted.
Using higher concurrency limit might be useful but given the
complexity of workqueue usage in xfs, proceeding cautiously seems
better.
* xfs_mru_reap_wq is converted to non-ordered workqueue with max
concurrency of 1 as the work items don't require any specific
ordering and already have proper synchronization. It seems it was
singlethreaded to save worker threads, which is no longer a concern.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alex Elder <aelder@sgi.com>
Cc: xfs-masters@oss.sgi.com
Cc: Christoph Hellwig <hch@infradead.org>
When filling in the middle of a previous delayed allocation in
xfs_bmap_add_extent_delay_real, set br_startblock of the new delay
extent to the right to nullstartblock instead of 0 before inserting
the extent into the ifork (xfs_iext_insert), rather than setting
br_startblock afterward.
Adding the extent into the ifork with br_startblock=0 can lead to
the extent being copied into the btree by xfs_bmap_extent_to_btree
if we happen to convert from extents format to btree format before
updating br_startblock with the correct value. The unexpected
addition of this delay extent to the btree can cause subsequent
XFS_WANT_CORRUPTED_GOTO filesystem shutdown in several
xfs_bmap_add_extent_delay_real cases where we are converting a delay
extent to real and unexpectedly find an extent already inserted.
For example:
911 case BMAP_LEFT_FILLING:
912 /*
913 * Filling in the first part of a previous delayed allocation.
914 * The left neighbor is not contiguous.
915 */
916 trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
917 xfs_bmbt_set_startoff(ep, new_endoff);
918 temp = PREV.br_blockcount - new->br_blockcount;
919 xfs_bmbt_set_blockcount(ep, temp);
920 xfs_iext_insert(ip, idx, 1, new, state);
921 ip->i_df.if_lastex = idx;
922 ip->i_d.di_nextents++;
923 if (cur == NULL)
924 rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
925 else {
926 rval = XFS_ILOG_CORE;
927 if ((error = xfs_bmbt_lookup_eq(cur, new->br_startoff,
928 new->br_startblock, new->br_blockcount,
929 &i)))
930 goto done;
931 XFS_WANT_CORRUPTED_GOTO(i == 0, done);
With the bogus extent in the btree we shutdown the filesystem at
931. The conversion from extents to btree format happens when the
number of extents in the inode increases above ip->i_df.if_ext_max.
xfs_bmap_extent_to_btree copies extents from the ifork into the
btree, ignoring all delalloc extents which are denoted by
br_startblock having some value of nullstartblock.
SGI-PV: 1013221
Signed-off-by: Ben Myers <bpm@sgi.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Commit 368e136 ("xfs: remove duplicate code from dquot reclaim") fails
to unlock the dquot freelist when the number of loop restarts is
exceeded in xfs_qm_dqreclaim_one(). This causes hangs in memory
reclaim.
Rework the loop control logic into an unwind stack that all the
different cases jump into. This means there is only one set of code
that processes the loop exit criteria, and simplifies the unlocking
of all the items from different points in the loop. It also fixes a
double increment of the restart counter from the qi_dqlist_lock
case.
Reported-by: Malcolm Scott <lkml@malc.org.uk>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Failure to commit a transaction into the CIL is not handled
correctly. This currently can only happen when racing with a
shutdown and requires an explicit shutdown check, so it rare and can
be avoided. Remove the shutdown check and make the CIL commit a void
function to indicate it will always succeed, thereby removing the
incorrectly handled failure case.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
The extent size hint can be set to larger than an AG. This means
that the alignment process can push the range to be allocated
outside the bounds of the AG, resulting in assert failures or
corrupted bmbt records. Similarly, if the extsize is larger than the
maximum extent size supported, the alignment process will produce
extents that are too large to fit into the bmbt records, resulting
in a different type of assert/corruption failure.
Fix this by limiting extsize at the time іt is set firstly to be
less than MAXEXTLEN, then to be a maximum of half the size of the
AGs in the filesystem for non-realtime inodes. Realtime inodes do
not allocate out of AGs, so don't have to be restricted by the size
of AGs.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
When doing delayed allocation, if the allocation size is for a
maximally sized extent, extent size alignment can push it over this
limit. This results in an assert failure in xfs_bmbt_set_allf() as
the extent length is too large to find in the extent record.
Fix this by ensuring that we allow for space that extent size
alignment requires (up to 2 * (extsize -1) blocks as we have to
handle both head and tail alignment) when limiting the maximum size
of the extent.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Delayed allocation extents can be larger than AGs, so when trying to
convert a large range we may scan every AG inside
xfs_bmap_alloc_nullfb() trying to find an AG with a size larger than
an AG. We should stop when we find the first AG with a maximum
possible allocation size. This causes excessive CPU usage when there
are lots of AGs.
The same problem occurs when doing preallocation of a range larger
than an AG.
Fix the problem by limiting real allocation lengths to the maximum
that an AG can support. This means if we have empty AGs, we'll stop
the search at the first of them. If there are no empty AGs, we'll
still scan them all, but that is a different problem....
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
rounddown_power_of_2() returns an undefined result when passed a
value of zero. The specualtive delayed allocation code is doing this
when the inode is zero length. Hence occasionally the preallocation
is much, much larger than is necessary (e.g. 8GB for a 270 _byte_
file). Ensure we don't even pass a zero value to this function so
the result of preallocation is always the desired size.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
After test 139, kmemleak shows:
unreferenced object 0xffff880078b405d8 (size 400):
comm "xfs_io", pid 4904, jiffies 4294909383 (age 1186.728s)
hex dump (first 32 bytes):
60 c1 17 79 00 88 ff ff 60 c1 17 79 00 88 ff ff `..y....`..y....
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff81afb04d>] kmemleak_alloc+0x2d/0x60
[<ffffffff8115c6cf>] kmem_cache_alloc+0x13f/0x2b0
[<ffffffff814aaa97>] kmem_zone_alloc+0x77/0xf0
[<ffffffff814aab2e>] kmem_zone_zalloc+0x1e/0x50
[<ffffffff8147cd6b>] xfs_efi_init+0x4b/0xb0
[<ffffffff814a4ee8>] xfs_trans_get_efi+0x58/0x90
[<ffffffff81455fab>] xfs_bmap_finish+0x8b/0x1d0
[<ffffffff814851b4>] xfs_itruncate_finish+0x2c4/0x5d0
[<ffffffff814a970f>] xfs_setattr+0x8df/0xa70
[<ffffffff814b5c7b>] xfs_vn_setattr+0x1b/0x20
[<ffffffff8117dc00>] notify_change+0x170/0x2e0
[<ffffffff81163bf6>] do_truncate+0x66/0xa0
[<ffffffff81163d0b>] sys_ftruncate+0xdb/0xe0
[<ffffffff8103a002>] system_call_fastpath+0x16/0x1b
[<ffffffffffffffff>] 0xffffffffffffffff
The cause of the leak is that the "remove" parameter of IOP_UNPIN()
is never set when a CIL push is aborted. This means that the EFI
item is never freed if it was in the push being cancelled. The
problem is specific to delayed logging, but has uncovered a couple
of problems with the handling of IOP_UNPIN(remove).
Firstly, we cannot safely call xfs_trans_del_item() from IOP_UNPIN()
in the CIL commit failure path or the iclog write failure path
because for delayed loging we have no transaction context. Hence we
must only call xfs_trans_del_item() if the log item being unpinned
has an active log item descriptor.
Secondly, xfs_trans_uncommit() does not handle log item descriptor
freeing during the traversal of log items on a transaction. It can
reference a freed log item descriptor when unpinning an EFI item.
Hence it needs to use a safe list traversal method to allow items to
be removed from the transaction during IOP_UNPIN().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
On platforms that call panic() inside their BUG() macro (m68k/sun3, and
all platforms that don't set HAVE_ARCH_BUG), compilation fails with:
| fs/xfs/support/debug.c: In function ‘xfs_cmn_err’:
| fs/xfs/support/debug.c:92: error: called object ‘panic’ is not a function
as the local variable "panic" conflicts with the "panic()" function.
Rename the local variable to resolve this.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently all filesystems except XFS implement fallocate asynchronously,
while XFS forced a commit. Both of these are suboptimal - in case of O_SYNC
I/O we really want our allocation on disk, especially for the !KEEP_SIZE
case where we actually grow the file with user-visible zeroes. On the
other hand always commiting the transaction is a bad idea for fast-path
uses of fallocate like for example in recent Samba versions. Given
that block allocation is a data plane operation anyway change it from
an inode operation to a file operation so that we have the file structure
available that lets us check for O_SYNC.
This also includes moving the code around for a few of the filesystems,
and remove the already unnedded S_ISDIR checks given that we only wire
up fallocate for regular files.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Instead of various home grown checks that might need updates for new
flags just check for any bit outside the mask of the features supported
by the filesystem. This makes the check future proof for any newly
added flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
block: ensure that completion error gets properly traced
blktrace: add missing probe argument to block_bio_complete
block cfq: don't use atomic_t for cfq_group
block cfq: don't use atomic_t for cfq_queue
block: trace event block fix unassigned field
block: add internal hd part table references
block: fix accounting bug on cross partition merges
kref: add kref_test_and_get
bio-integrity: mark kintegrityd_wq highpri and CPU intensive
block: make kblockd_workqueue smarter
Revert "sd: implement sd_check_events()"
block: Clean up exit_io_context() source code.
Fix compile warnings due to missing removal of a 'ret' variable
fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
cfq-iosched: don't check cfqg in choose_service_tree()
fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
cdrom: export cdrom_check_events()
sd: implement sd_check_events()
sr: implement sr_check_events()
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (41 commits)
fs: add documentation on fallocate hole punching
Gfs2: fail if we try to use hole punch
Btrfs: fail if we try to use hole punch
Ext4: fail if we try to use hole punch
Ocfs2: handle hole punching via fallocate properly
XFS: handle hole punching via fallocate properly
fs: add hole punching to fallocate
vfs: pass struct file to do_truncate on O_TRUNC opens (try #2)
fix signedness mess in rw_verify_area() on 64bit architectures
fs: fix kernel-doc for dcache::prepend_path
fs: fix kernel-doc for dcache::d_validate
sanitize ecryptfs ->mount()
switch afs
move internal-only parts of ncpfs headers to fs/ncpfs
switch ncpfs
switch 9p
pass default dentry_operations to mount_pseudo()
switch hostfs
switch affs
switch configfs
...
This patch simply allows XFS to handle the hole punching flag in fallocate
properly. I've tested this with a little program that does a bunch of random
hole punching with FL_KEEP_SIZE and without it to make sure it does the right
thing. Thanks,
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
We currently have a global error message buffer in cmn_err that is
protected by a spin lock that disables interrupts. Recently there
have been reports of NMI timeouts occurring when the console is
being flooded by SCSI error reports due to cmn_err() getting stuck
trying to print to the console while holding this lock (i.e. with
interrupts disabled). The NMI watchdog is seeing this CPU as
non-responding and so is triggering a panic. While the trigger for
the reported case is SCSI errors, pretty much anything that spams
the kernel log could cause this to occur.
Realistically the only reason that we have the intemediate message
buffer is to prepend the correct kernel log level prefix to the log
message. The only reason we have the lock is to protect the global
message buffer and the only reason the message buffer is global is
to keep it off the stack. Hence if we can avoid needing a global
message buffer we avoid needing the lock, and we can do this with a
small amount of cleanup and some preprocessor tricks:
1. clean up xfs_cmn_err() panic mask functionality to avoid
needing debug code in xfs_cmn_err()
2. remove the couple of "!" message prefixes that still exist that
the existing cmn_err() code steps over.
3. redefine CE_* levels directly to KERN_*
4. redefine cmn_err() and friends to use printk() directly
via variable argument length macros.
By doing this, we can completely remove the cmn_err() code and the
lock that is causing the problems, and rely solely on printk()
serialisation to ensure that we don't get garbled messages.
A series of followup patches is really needed to clean up all the
cmn_err() calls and related messages properly, but that results in a
series that is not easily back portable to enterprise kernels. Hence
this initial fix is only to address the direct problem in the lowest
impact way possible.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
I received a ppc64 bug report involving xfs but the assertion was
filtered out by the console log level. Use KERN_CRIT to ensure it
makes it out.
Signed-off-by: Anton Blanchard <anton@samba.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
In fs/xfs/xfs_trans.c::xfs_trans_unreserve_and_mod_sb() at the out:
label we have this:
ASSERT(error = 0);
I believe a comparison was intended, not an assignment. If I'm
right, the patch below fixes that up.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Alex Elder <aelder@sgi.com>
If we get an IO error on a synchronous superblock write, we attach an
error release function to it so that when the last reference goes away
the release function is called and the buffer is invalidated and
unlocked. The buffer is left locked until the release function is
called so that other concurrent users of the buffer will be locked out
until the buffer error is fully processed.
Unfortunately, for the superblock buffer the filesyetm itself holds a
reference to the buffer which prevents the reference count from
dropping to zero and the release function being called. As a result,
once an IO error occurs on a sync write, the buffer will never be
unlocked and all future attempts to lock the buffer will hang.
To make matters worse, this problems is not unique to such buffers;
if there is a concurrent _xfs_buf_find() running, the lookup will grab
a reference to the buffer and then wait on the buffer lock, preventing
the reference count from ever falling to zero and hence unlocking the
buffer.
As such, the whole b_relse function implementation is broken because it
cannot rely on the buffer reference count falling to zero to unlock the
errored buffer. The synchronous write error path is the only path that
uses this callback - it is used to ensure that the synchronous waiter
gets the buffer error before the error state is cleared from the buffer
by the release function.
Given that the only sychronous buffer writes now go through xfs_bwrite
and the error path in question can only occur for a write of a dirty,
logged buffer, we can move most of the b_relse processing to happen
inline in xfs_buf_iodone_callbacks, just like a normal I/O completion.
In addition to that we make sure the error is not cleared in
xfs_buf_iodone_callbacks, so that xfs_bwrite can reliably check it.
Given that xfs_bwrite keeps the buffer locked until it has waited for
it and checked the error this allows to reliably propagate the error
to the caller, and make sure that the buffer is reliably unlocked.
Given that xfs_buf_iodone_callbacks was the only instance of the
b_relse callback we can remove it entirely.
Based on earlier patches by Dave Chinner and Ajeet Yadav.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Ajeet Yadav <ajeet.yadav.77@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Allow manual discards from userspace using the FITRIM ioctl. This is not
intended to be run during normal workloads, as the freepsace btree walks
can cause large performance degradation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
To ensure the log is covered and the filesystem idles correctly, we
need to ensure that dummy transactions hit the disk and do not stay
pinned in memory. If the superblock is pinned in memory, it can't
be flushed so the log covering cannot make progress. The result is
dependent on timing - more oftent han not we continue to issues a
log covering transaction every 36s rather than idling after ~90s.
Fix this by making the log covering transaction synchronous. To
avoid additional log force from xfssyncd, make the log covering
transaction take the place of the existing log force in the xfssyncd
background sync process.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
This merge pulls the XFS master branch into the latest Linus master.
This results in a merge conflict whose best fix is not obvious.
I manually fixed the conflict, in "fs/xfs/xfs_iget.c".
Dave Chinner had done work that resulted in RCU freeing of inodes
separate from what Nick Piggin had done, and their results differed
slightly in xfs_inode_free(). The fix updates Nick's call_rcu()
with the use of VFS_I(), while incorporating needed updates to some
XFS inode fields implemented in Dave's series. Dave's RCU callback
function has also been removed.
Signed-off-by: Alex Elder <aelder@sgi.com>
When two concurrent unaligned, non-overlapping direct IOs are issued
to the same block, the direct Io layer will race to zero the block.
The result is that one of the concurrent IOs will overwrite data
written by the other IO with zeros. This is demonstrated by the
xfsqa test 240.
To avoid this problem, serialise all unaligned direct IOs to an
inode with a big hammer. We need a big hammer approach as we need to
serialise AIO as well, so we can't just block writes on locks.
Hence, the big hammer is calling xfs_ioend_wait() while holding out
other unaligned direct IOs from starting.
We don't bother trying to serialised aligned vs unaligned IOs as
they are overlapping IO and the result of concurrent overlapping IOs
is undefined - the result of either IO is a valid result so we let
them race. Hence we only penalise unaligned IO, which already has a
major overhead compared to aligned IO so this isn't a major problem.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The buffered IO and direct IO write paths share a common set of
checks and limiting code prior to issuing the write. Factor that
into a common helper function.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Complete the split of the different write IO paths by splitting the
buffered IO write path out of xfs_file_aio_write(). This makes the
different mechanisms of the write patchs easier to follow.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The current xfs_file_aio_write code is a mess of locking shenanigans
to handle the different locking requirements of buffered and direct
IO. Start to clean this up by disentangling the direct IO path from
the mess.
This also removes the failed direct IO fallback path to buffered IO.
XFS handles all direct IO cases without needing to fall back to
buffered IO, so we can safely remove this unused path. This greatly
simplifies the logic and locking needed in the write path.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We need to obtain the i_mutex, i_iolock and i_ilock during the read
and write paths. Add a set of wrapper functions to neatly
encapsulate the lock ordering and shared/exclusive semantics to make
the locking easier to follow and get right.
Note that this changes some of the exclusive locking serialisation in
that serialisation will occur against the i_mutex instead of the
XFS_IOLOCK_EXCL. This does not change any behaviour, and it is
arguably more efficient to use the mutex for such serialisation than
the rw_sem.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xfs_file_aio_write() only returns the error from synchronous
flushing of the data and inode if error == 0. At the point where
error is being checked, it is guaranteed to be > 0. Therefore any
errors returned by the data or fsync flush will never be returned.
Fix the checks so we overwrite the current error once and only if an
error really occurred.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (33 commits)
usb: don't use flush_scheduled_work()
speedtch: don't abuse struct delayed_work
media/video: don't use flush_scheduled_work()
media/video: explicitly flush request_module work
ioc4: use static work_struct for ioc4_load_modules()
init: don't call flush_scheduled_work() from do_initcalls()
s390: don't use flush_scheduled_work()
rtc: don't use flush_scheduled_work()
mmc: update workqueue usages
mfd: update workqueue usages
dvb: don't use flush_scheduled_work()
leds-wm8350: don't use flush_scheduled_work()
mISDN: don't use flush_scheduled_work()
macintosh/ams: don't use flush_scheduled_work()
vmwgfx: don't use flush_scheduled_work()
tpm: don't use flush_scheduled_work()
sonypi: don't use flush_scheduled_work()
hvsi: don't use flush_scheduled_work()
xen: don't use flush_scheduled_work()
gdrom: don't use flush_scheduled_work()
...
Fixed up trivial conflict in drivers/media/video/bt8xx/bttv-input.c
as per Tejun.
This simple implementation just checks for no ACLs on the inode, and
if so, then the rcu-walk may proceed, otherwise fail it.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
RCU free the struct inode. This will allow:
- Subsequent store-free path walking patch. The inode must be consulted for
permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
to take i_lock no longer need to take sb_inode_list_lock to walk the list in
the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
page lock to follow page->mapping.
The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.
In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.
The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
Conflicts:
MAINTAINERS
arch/arm/mach-omap2/pm24xx.c
drivers/scsi/bfa/bfa_fcpim.c
Needed to update to apply fixes for which the old branch was too
outdated.
The only thing that the grant lock remains to protect is the grant head
manipulations when adding or removing space from the log. These calculations
are already based on atomic variables, so we can already update them safely
without locks. However, the grant head manpulations require atomic multi-step
calculations to be executed, which the algorithms currently don't allow.
To make these multi-step calculations atomic, convert the algorithms to
compare-and-exchange loops on the atomic variables. That is, we sample the old
value, perform the calculation and use atomic64_cmpxchg() to attempt to update
the head with the new value. If the head has not changed since we sampled it,
it will succeed and we are done. Otherwise, we rerun the calculation again from
a new sample of the head.
This allows us to remove the grant lock from around all the grant head space
manipulations, and that effectively removes the grant lock from the log
completely. Hence we can remove the grant lock completely from the log at this
point.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The log grant ticket wait queues are currently protected by the log
grant lock. However, the queues are functionally independent from
each other, and operations on them only require serialisation
against other queue operations now that all of the other log
variables they use are atomic values.
Hence, we can make them independent of the grant lock by introducing
new locks just to protect the lists operations. because the lists
are independent, we can use a lock per list and ensure that reserve
and write head queuing do not contend.
To ensure forced shutdowns work correctly in conjunction with the
new fast paths, ensure that we check whether the log has been shut
down in the grant functions once we hold the relevant spin locks but
before we go to sleep. This is needed to co-ordinate correctly with
the wakeups that are issued on the ticket queues so we don't leave
any processes sleeping on the queues during a shutdown.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
cancel_rearming_delayed_work[queue]() has been superceded by
cancel_delayed_work_sync() quite some time ago. Convert all the
in-kernel users. The conversions are completely equivalent and
trivial.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alex Elder <aelder@sgi.com>
Cc: xfs-masters@oss.sgi.com
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: netfilter-devel@vger.kernel.org
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org
Now that we don't mark VFS inodes dirty anymore for internal
timestamp changes, but rely on the transaction subsystem to push
them out, we need to explicitly log the source inode in rename after
updating it's timestamps to make sure the changes actually get
forced out by sync/fsync or an AIL push.
We already account for the fourth inode in the log reservation, as a
rename of directories needs to update the nlink field, so just
adding the xfs_trans_log_inode call is enough.
This fixes the xfsqa 065 regression introduced by:
"xfs: don't use vfs writeback for pure metadata modifications"
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Convert the log grant heads to atomic64_t types in preparation for
converting the accounting algorithms to atomic operations. his patch
just converts the variables; the algorithmic changes are in a
separate patch for clarity.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
log->l_tail_lsn is currently protected by the log grant lock. The
lock is only needed for serialising readers against writers, so we
don't really need the lock if we make the l_tail_lsn variable an
atomic. Converting the l_tail_lsn variable to an atomic64_t means we
can start to peel back the grant lock from various operations.
Also, provide functions to safely crack an atomic LSN variable into
it's component pieces and to recombined the components into an
atomic variable. Use them where appropriate.
This also removes the need for explicitly holding a spinlock to read
the l_tail_lsn on 32 bit platforms.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
log->l_last_sync_lsn is updated in only one critical spot - log
buffer Io completion - and is protected by the grant lock here. This
requires the grant lock to be taken for every log buffer IO
completion. Converting the l_last_sync_lsn variable to an atomic64_t
means that we do not need to take the grant lock in log buffer IO
completion to update it.
This also removes the need for explicitly holding a spinlock to read
the l_last_sync_lsn on 32 bit platforms.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The xlog_grant_push_ail() currently takes the grant lock internally to sample
the tail lsn, last sync lsn and the reserve grant head. Most of the callers
already hold the grant lock but have to drop it before calling
xlog_grant_push_ail(). This is a left over from when the AIL tail pushing was
done in line and hence xlog_grant_push_ail had to drop the grant lock. AIL push
is now done in another thread and hence we can safely hold the grant lock over
the entire xlog_grant_push_ail call.
Push the grant lock outside of xlog_grant_push_ail() to simplify the locking
and synchronisation needed for tail pushing. This will reduce traffic on the
grant lock by itself, but this is only one step in preparing for the complete
removal of the grant lock.
While there, clean up the formatting of xlog_grant_push_ail() to match the
rest of the XFS code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The log grant queues are one of the few places left using sv_t
constructs for waiting. Given we are touching this code, we should
convert them to plain wait queues. While there, convert all the
other sv_t users in the log code as well.
Seeing as this removes the last users of the sv_t type, remove the
header file defining the wrapper and the fragments that still
reference it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Prepare for switching the grant heads to atomic variables by
combining the two 32 bit values that make up the grant head into a
single 64 bit variable. Provide wrapper functions to combine and
split the grant heads appropriately for calculations and use them as
necessary.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The log grant space calculations are repeated for both write and
reserve grant heads. To make it simpler to convert the calculations
toa different algorithm, factor them so both the gratn heads use the
same calculation functions. Once this is done we can drop the
wrappers that are used in only a couple of place to update both
grant heads at once as they don't provide any particular value.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Factor repeated debug code out of grant head manipulation functions into a
separate function. This removes ifdef DEBUG spagetti from the code and makes
the code easier to follow.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The grant write and reserve queues use a roll-your-own double linked
list, so convert it to a standard list_head structure and convert
all the list traversals to use list_for_each_entry(). We can also
get rid of the XLOG_TIC_IN_Q flag as we can use the list_empty()
check to tell if the ticket is in a list or not.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We now have two copies of AIL delete operations that are mostly
duplicate functionality. The single log item deletes can be
implemented via the bulk updates by turning xfs_trans_ail_delete()
into a simple wrapper. This removes all the duplicate delete
functionality and associated helpers.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We now have two copies of AIL insert operations that are mostly
duplicate functionality. The single log item updates can be
implemented via the bulk updates by turning xfs_trans_ail_update()
into a simple wrapper. This removes all the duplicate insert
functionality and associated helpers.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When inode buffer IO completes, usually all of the inodes are removed from the
AIL. This involves processing them one at a time and taking the AIL lock once
for every inode. When all CPUs are processing inode IO completions, this causes
excessive amount sof contention on the AIL lock.
Instead, change the way we process inode IO completion in the buffer
IO done callback. Allow the inode IO done callback to walk the list
of IO done callbacks and pull all the inodes off the buffer in one
go and then process them as a batch.
Once all the inodes for removal are collected, take the AIL lock
once and do a bulk removal operation to minimise traffic on the AIL
lock.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
To allow buffer iodone callbacks to consume multiple items off the
callback list, first we need to convert the xfs_buf_do_callbacks()
to consume items and always pull the next item from the head of the
list.
The means the item list walk is never dependent on knowing the
next item on the list and hence allows callbacks to remove items
from the list as well. This allows callbacks to do bulk operations
by scanning the list for identical callbacks, consuming them all
and then processing them in bulk, negating the need for multiple
callbacks of that type.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The xfaild often tries to rest to wait for congestion to pass of for
IO to complete, but is regularly woken in tail-pushing situations.
In severe cases, the xfsaild is getting woken tens of thousands of
times a second. Reduce the number needless wakeups by only waking
the xfsaild if the new target is larger than the old one. Further
make short sleeps uninterruptible as they occur when the xfsaild has
decided it needs to back off to allow some IO to complete and being
woken early is counter-productive.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When inserting items into the AIL from the transaction committed
callbacks, we take the AIL lock for every single item that is to be
inserted. For a CIL checkpoint commit, this can be tens of thousands
of individual inserts, yet almost all of the items will be inserted
at the same point in the AIL because they have the same index.
To reduce the overhead and contention on the AIL lock for such
operations, introduce a "bulk insert" operation which allows a list
of log items with the same LSN to be inserted in a single operation
via a list splice. To do this, we need to pre-sort the log items
being committed into a temporary list for insertion.
The complexity is that not every log item will end up with the same
LSN, and not every item is actually inserted into the AIL. Items
that don't match the commit LSN will be inserted and unpinned as per
the current one-at-a-time method (relatively rare), while items that
are not to be inserted will be unpinned and freed immediately. Items
that are to be inserted at the given commit lsn are placed in a
temporary array and inserted into the AIL in bulk each time the
array fills up.
As a result of this, we trade off AIL hold time for a significant
reduction in traffic. lock_stat output shows that the worst case
hold time is unchanged, but contention from AIL inserts drops by an
order of magnitude and the number of lock traversal decreases
significantly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
xfs_ail_delete() has a needlessly complex interface. It returns the log item
that was passed in for deletion (which the callers then assert is identical to
the one passed in), and callers of xfs_ail_delete() still need to invalidate
current traversal cursors.
Make xfs_ail_delete() return void, move the cursor invalidation inside it, and
clean up the callers just to use the log item pointer they passed in.
While cleaning up, remove the messy and unnecessary "/* ARGUSED */" comments
around all these functions.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
EFI/EFD interactions are protected from races by the AIL lock. They
are the only type of log items that require the the AIL lock to
serialise internal state, so they need to be separated from the AIL
lock before we can do bulk insert operations on the AIL.
To acheive this, convert the counter of the number of extents in the
EFI to an atomic so it can be safely manipulated by EFD processing
without locks. Also, convert the EFI state flag manipulations to use
atomic bit operations so no locks are needed to record state
changes. Finally, use the state bits to determine when it is safe to
free the EFI and clean up the code to do this neatly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
XFS_EFI_CANCELED has not been set in the code base since
xfs_efi_cancel() was removed back in 2006 by commit
065d312e15 ("[XFS] Remove unused
iop_abort log item operation), and even then xfs_efi_cancel() was
never called. I haven't tracked it back further than that (beyond
git history), but it indicates that the handling of EFIs in
cancelled transactions has been broken for a long time.
Basically, when we get an IOP_UNPIN(lip, 1); call from
xfs_trans_uncommit() (i.e. remove == 1), if we don't free the log
item descriptor we leak it. Fix the behviour to be correct and kill
the XFS_EFI_CANCELED flag.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that the buffer reclaim infrastructure can handle different reclaim
priorities for different types of buffers, reconnect the hooks in the
XFS code that has been sitting dormant since it was ported to Linux. This
should finally give use reclaim prioritisation that is on a par with the
functionality that Irix provided XFS 15 years ago.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Introduce a per-buftarg LRU for memory reclaim to operate on. This
is the last piece we need to put in place so that we can fully
control the buffer lifecycle. This allows XFS to be responsibile for
maintaining the working set of buffers under memory pressure instead
of relying on the VM reclaim not to take pages we need out from
underneath us.
The implementation introduces a b_lru_ref counter into the buffer.
This is currently set to 1 whenever the buffer is referenced and so is used to
determine if the buffer should be added to the LRU or not when freed.
Effectively it allows lazy LRU initialisation of the buffer so we do not need
to touch the LRU list and locks in xfs_buf_find().
Instead, when the buffer is being released and we drop the last
reference to it, we check the b_lru_ref count and if it is none zero
we re-add the buffer reference and add the inode to the LRU. The
b_lru_ref counter is decremented by the shrinker, and whenever the
shrinker comes across a buffer with a zero b_lru_ref counter, if
released the LRU reference on the buffer. In the absence of a lookup
race, this will result in the buffer being freed.
This counting mechanism is used instead of a reference flag so that
it is simple to re-introduce buffer-type specific reclaim reference
counts to prioritise reclaim more effectively. We still have all
those hooks in the XFS code, so this will provide the infrastructure
to re-implement that functionality.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Recent tests writing lots of small files showed the flusher thread
being CPU bound and taking a long time to do allocations on a debug
kernel. perf showed this as the prime reason:
samples pcnt function DSO
_______ _____ ___________________________ _________________
224648.00 36.8% xfs_error_test [kernel.kallsyms]
86045.00 14.1% xfs_btree_check_sblock [kernel.kallsyms]
39778.00 6.5% prandom32 [kernel.kallsyms]
37436.00 6.1% xfs_btree_increment [kernel.kallsyms]
29278.00 4.8% xfs_btree_get_rec [kernel.kallsyms]
27717.00 4.5% random32 [kernel.kallsyms]
Walking btree blocks during allocation checking them requires each
block (a cache hit, so no I/O) call xfs_error_test(), which then
does a random32() call as the first operation. IOWs, ~50% of the
CPU is being consumed just testing whether we need to inject an
error, even though error injection is not active.
Kill this overhead when error injection is not active by adding a
global counter of active error traps and only calling into
xfs_error_test when fault injection is active.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When an inode has been marked stale because the cluster is being
freed, we don't want to (re-)insert this inode into the AIL. There
is a race condition where the cluster buffer may be unpinned before
the inode is inserted into the AIL during transaction committed
processing. If the buffer is unpinned before the inode item has been
committed and inserted, then it is possible for the buffer to be
released and hence processthe stale inode callbacks before the inode
is inserted into the AIL.
In this case, we then insert a clean, stale inode into the AIL which
will never get removed by an IO completion. It will, however, get
reclaimed and that triggers an assert in xfs_inode_free()
complaining about freeing an inode still in the AIL.
This race can be avoided by not moving stale inodes forward in the AIL
during transaction commit completion processing. This closes the
race condition by ensuring we never insert clean stale inodes into
the AIL. It is safe to do this because a dirty stale inode, by
definition, must already be in the AIL.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
There is an assumption in the parts of XFS that flushing a dirty
file will make all the delayed allocation blocks disappear from an
inode. That is, that after calling xfs_flush_pages() then
ip->i_delayed_blks will be zero.
This is an invalid assumption as we may have specualtive
preallocation beyond EOF and they are recorded in
ip->i_delayed_blks. A flush of the dirty pages of an inode will not
change the state of these blocks beyond EOF, so a non-zero
deeelalloc block count after a flush is valid.
The bmap code has an invalid ASSERT() that needs to be removed, and
the swapext code has a bug in that while it swaps the data forks
around, it fails to swap the i_delayed_blks counter associated with
the fork and hence can get the block accounting wrong.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
As reported by Nick Piggin, XFS is suffering from long pauses under
highly concurrent workloads when hosted on ramdisks. The problem is
that an inode buffer is stuck in the pinned state in memory and as a
result either the inode buffer or one of the inodes within the
buffer is stopping the tail of the log from being moved forward.
The system remains in this state until a periodic log force issued
by xfssyncd causes the buffer to be unpinned. The main problem is
that these are stale buffers, and are hence held locked until the
transaction/checkpoint that marked them state has been committed to
disk. When the filesystem gets into this state, only the xfssyncd
can cause the async transactions to be committed to disk and hence
unpin the inode buffer.
This problem was encountered when scaling the busy extent list, but
only the blocking lock interface was fixed to solve the problem.
Extend the same fix to the buffer trylock operations - if we fail to
lock a pinned, stale buffer, then force the log immediately so that
when the next attempt to lock it comes around, it will have been
unpinned.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Since the move to the new truncate sequence we call xfs_setattr to
truncate down excessively instanciated blocks. As shown by the testcase
in kernel.org BZ #22452 that doesn't work too well. Due to the confusion
of the internal inode size, and the VFS inode i_size it zeroes data that
it shouldn't.
But full blown truncate seems like overkill here. We only instanciate
delayed allocations in the write path, and given that we never released
the iolock we can't have converted them to real allocations yet either.
The only nasty case is pre-existing preallocation which we need to skip.
We already do this for page discard during writeback, so make the delayed
allocation block punching a generic function and call it from the failed
write path as well as xfs_aops_discard_page. The callers are
responsible for ensuring that partial blocks are not truncated away,
and that they hold the ilock.
Based on a fix originally from Christoph Hellwig. This version used
filesystem blocks as the range unit.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Before we introduce per-buftarg LRU lists, split the shrinker
implementation into per-buftarg shrinker callbacks. At the moment
we wake all the xfsbufds to run the delayed write queues to free
the dirty buffers and make their pages available for reclaim.
However, with an LRU, we want to be able to free clean, unused
buffers as well, so we need to separate the xfsbufd from the
shrinker callbacks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
now that we are using RCU protection for the inode cache lookups,
the lock is only needed on the modification side. Hence it is not
necessary for the lock to be a rwlock as there are no read side
holders anymore. Convert it to a spin lock to reflect it's exclusive
nature.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
With delayed logging greatly increasing the sustained parallelism of inode
operations, the inode cache locking is showing significant read vs write
contention when inode reclaim runs at the same time as lookups. There is
also a lot more write lock acquistions than there are read locks (4:1 ratio)
so the read locking is not really buying us much in the way of parallelism.
To avoid the read vs write contention, change the cache to use RCU locking on
the read side. To avoid needing to RCU free every single inode, use the built
in slab RCU freeing mechanism. This requires us to be able to detect lookups of
freed inodes, so enѕure that ever freed inode has an inode number of zero and
the XFS_IRECLAIM flag set. We already check the XFS_IRECLAIM flag in cache hit
lookup path, but also add a check for a zero inode number as well.
We canthen convert all the read locking lockups to use RCU read side locking
and hence remove all read side locking.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Introduce RCU freeing of XFS inodes so that we can convert lookup
traversals to use rcu_read_lock() protection. This patch only
introduces the RCU freeing to minimise the potential conflicts with
mainline if this is merged into mainline via a VFS patchset. It
abuses the i_dentry list for the RCU callback structure because the
VFS patches make this a union so it is safe to use like this and
simplifies and merge issues.
This patch uses basic RCU freeing rather than SLAB_DESTROY_BY_RCU.
The later lookup patches need the same "found free inode" protection
regardless of the RCU freeing method used, so once again the RCU
freeing method can be dealt with apprpriately at merge time without
affecting any other code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
A long standing problem for streaming writeѕ through the NFS server
has been that the NFS server opens and closes file descriptors on an
inode for every write. The result of this behaviour is that the
->release() function is called on every close and that results in
XFS truncating speculative preallocation beyond the EOF. This has
an adverse effect on file layout when multiple files are being
written at the same time - they interleave their extents and can
result in severe fragmentation.
To avoid this problem, keep track of ->release calls made on a dirty
inode. For most cases, an inode is only going to be opened once for
writing and then closed again during it's lifetime in cache. Hence
if there are multiple ->release calls when the inode is dirty, there
is a good chance that the inode is being accessed by the NFS server.
Hence set a flag the first time ->release is called while there are
delalloc blocks still outstanding on the inode.
If this flag is set when ->release is next called, then do no
truncate away the speculative preallocation - leave it there so that
subsequent writes do not need to reallocate the delalloc space. This
will prevent interleaving of extents of different inodes written
concurrently to the same AG.
If we get this wrong, it is not a big deal as we truncate
speculative allocation beyond EOF anyway in xfs_inactive() when the
inode is thrown out of the cache.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently the size of the speculative preallocation during delayed
allocation is fixed by either the allocsize mount option of a
default size. We are seeing a lot of cases where we need to
recommend using the allocsize mount option to prevent fragmentation
when buffered writes land in the same AG.
Rather than using a fixed preallocation size by default (up to 64k),
make it dynamic by basing it on the current inode size. That way the
EOF preallocation will increase as the file size increases. Hence
for streaming writes we are much more likely to get large
preallocations exactly when we need it to reduce fragementation.
For default settings, the size of the initial extents is determined
by the number of parallel writers and the amount of memory in the
machine. For 4GB RAM and 4 concurrent 32GB file writes:
EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL
0: [0..1048575]: 1048672..2097247 0 (1048672..2097247) 1048576
1: [1048576..2097151]: 5242976..6291551 0 (5242976..6291551) 1048576
2: [2097152..4194303]: 12583008..14680159 0 (12583008..14680159) 2097152
3: [4194304..8388607]: 25165920..29360223 0 (25165920..29360223) 4194304
4: [8388608..16777215]: 58720352..67108959 0 (58720352..67108959) 8388608
5: [16777216..33554423]: 117440584..134217791 0 (117440584..134217791) 16777208
6: [33554424..50331511]: 184549056..201326143 0 (184549056..201326143) 16777088
7: [50331512..67108599]: 251657408..268434495 0 (251657408..268434495) 16777088
and for 16 concurrent 16GB file writes:
EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL
0: [0..262143]: 2490472..2752615 0 (2490472..2752615) 262144
1: [262144..524287]: 6291560..6553703 0 (6291560..6553703) 262144
2: [524288..1048575]: 13631592..14155879 0 (13631592..14155879) 524288
3: [1048576..2097151]: 30408808..31457383 0 (30408808..31457383) 1048576
4: [2097152..4194303]: 52428904..54526055 0 (52428904..54526055) 2097152
5: [4194304..8388607]: 104857704..109052007 0 (104857704..109052007) 4194304
6: [8388608..16777215]: 209715304..218103911 0 (209715304..218103911) 8388608
7: [16777216..33554423]: 452984848..469762055 0 (452984848..469762055) 16777208
Because it is hard to take back specualtive preallocation, cases
where there are large slow growing log files on a nearly full
filesystem may cause premature ENOSPC. Hence as the filesystem nears
full, the maximum dynamic prealloc size іs reduced according to this
table (based on 4k block size):
freespace max prealloc size
>5% full extent (8GB)
4-5% 2GB (8GB >> 2)
3-4% 1GB (8GB >> 3)
2-3% 512MB (8GB >> 4)
1-2% 256MB (8GB >> 5)
<1% 128MB (8GB >> 6)
This should reduce the amount of space held in speculative
preallocation for such cases.
The allocsize mount option turns off the dynamic behaviour and fixes
the prealloc size to whatever the mount option specifies. i.e. the
behaviour is unchanged.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
When listing attributes, we are doiing memory allocations under the
inode ilock using only KM_SLEEP. This allows memory allocation to
recurse back into the filesystem and do writeback, which may the
ilock we already hold on the current inode. THis will deadlock.
Hence use KM_NOFS for such allocations outside of transaction
context to ensure that reclaim recursion does not occur.
Reported-by: Nick Piggin <npiggin@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The XFS iolock needs to be re-initialised to a new lock class before
it enters reclaim to prevent lockdep false positives. Unfortunately,
this is not sufficient protection as inodes in the XFS_IRECLAIMABLE
state can be recycled and not re-initialised before being reused.
We need to re-initialise the lock state when transfering out of
XFS_IRECLAIMABLE state to XFS_INEW, but we need to keep the same
class as if the inode was just allocated. Hence we need a specific
lockdep class variable for the iolock so that both initialisations
use the same class.
While there, add a specific class for inodes in the reclaim state so
that it is easy to tell from lockdep reports what state the inode
was in that generated the report.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add a new xfs_alloc_find_best_extent that does a forward/backward
search in the allocation btree. That code previously was existed
two times in xfs_alloc_ag_vextent_near, once for each search
direction.
Based on an earlier patch from Dave Chinner.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Use a goto label to consolidate all block not found cases, and add a
tracepoint for them. Also clean up a few whitespace issues.
Based on an earlier patch from Dave Chinner.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Move the buffer locking into the callers as they need to do it
wether they call xfs_map_at_offset or not. Remove the b_bdev
assignment, which is already done by get_blocks. Remove the
duplicate extent type asserts in xfs_convert_page just before
calling xfs_map_at_offset.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
After the last patches the code for overwrites is the same as for
delayed and unwritten extents except that it doesn't need to call
xfs_map_at_offset. Take care of that fact to simplify
xfs_vm_writepage.
The buffer loop now first checks the type of buffer and checks/sets
the ioend type, or continues to the next buffer if it's not
interesting to us. Only after that we validate the iomap and
perform the block mapping if needed, all in common code for the
cases where we have to do work.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
The all_bh flag is always set when entering the page clustering
machinery with a regular written extent, which means the check for
it is superflous.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
xfs_map_blocks always calls xfs_bmapi with the XFS_BMAPI_ENTIRE
entire flag, which tells it to not cap the extent at the passed in
size, but just treat the size as an minimum to map. This means
xfs_probe_cluster is entirely useless as we'll always get the whole
extent back anyway.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
No need to lock the extent map exclusive when performing an
overwrite, we know the extent map must already have been loaded by
get_blocks. Apply the non-blocking inode semantics to all mapping
types instead of just delayed allocations. Remove the handling of
not yet allocated blocks for the IO_UNWRITTEN case - if an extent is
marked as unwritten allocated in the buffer it must already have an
extent on disk.
Add asserts to verify all the assumptions above in debug builds.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Opencode the xfs_iomap code in it's two callers. The overlap of
passed flags already was minimal and will be further reduced in the
next patch.
As a side effect the BMAPI_* flags for xfs_bmapi and the IO_* flags
for I/O end processing are merged into a single set of flags, which
should be a bit more descriptive of the operation we perform.
Also improve the tracing by giving each caller it's own type set of
tracepoints.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Remove passing the BMAPI_* flags to these helpers, in
xfs_iomap_write_direct the check BMAPI_DIRECT was always true, and
in the xfs_iomap_write_delay path is was never checked at all.
Remove the nmap return value as we never make use of it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Don't trylock the buffer. We are the only one ever locking it for a
regular file address space, and trylock was only copied from the
generic code which did it due to the old buffer based writeout in
jbd. Also make sure to only write out the buffer if the iomap
actually is valid, because we wouldn't have a proper mapping
otherwise. In practice we will never get an invalid mapping here as
the page lock guarantees truncate doesn't race with us, but better
be safe than sorry. Also make sure we allocate a new ioend when
crossing boundaries between mappings, just like we do for delalloc
and unwritten extents. Again this currently doesn't matter as the
I/O end handler only cares for the boundaries for unwritten extents,
but this makes the code fully correct and the same as for
delalloc/unwritten extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
We'll never have BIO_EOPNOTSUPP set after calling submit_bio as this
can only happen for discards, and used to happen for barriers, none
of which is every submitted by xfs_submit_ioend_bio. Also remove
the loop around bio_alloc as it will never fail due to it's mempool
backing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Currently we only refuse a "read-only" mapping for writing out
unwritten and delayed buffers, and refuse any other for overwrites.
Improve the checks to require delalloc mappings for delayed buffers,
and unwritten extent mappings for unwritten extents.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Dispatch to a different helper for phase1 vs phase2 in
xlog_recover_commit_trans instead of doing it in all the
low-level functions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Merge the call to xlog_recover_reorder_trans and the loop over the
recovery items from xlog_recover_do_trans into xlog_recover_commit_trans,
and keep the switch statement over the log item types as a separate helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
XFS used to support different types of buffer log items long time
ago. Remove the switch statements checking the log item type in
various buffer recovery helpers that were left over from those days
and the rather useless xlog_recover_do_buffer_pass2 wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We now support mounting and using filesystems with 64-bit inodes
even when not mounted with the inode64 option (which now only
controls if we allocate new inodes in that space or not). Make sure
we always use large NFS file handles when exporting a filesystem
that may contain 64-bit inodes. Note that this only affects newly
generated file handles, any outstanding 32-bit file handle is still
accepted.
[hch: the comment and commit log are mine, the rest is from a patch
snipplet from Samuel]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
After recent blkdev_get() modifications, open_by_devnum() and
open_bdev_exclusive() are simple wrappers around blkdev_get().
Replace them with blkdev_get_by_dev() and blkdev_get_by_path().
blkdev_get_by_dev() is identical to open_by_devnum().
blkdev_get_by_path() is slightly different in that it doesn't
automatically add %FMODE_EXCL to @mode.
All users are converted. Most conversions are mechanical and don't
introduce any behavior difference. There are several exceptions.
* btrfs now sets FMODE_EXCL in btrfs_device->mode, so there's no
reason to OR it explicitly on blkdev_put().
* gfs2, nilfs2 and the generic mount_bdev() now set FMODE_EXCL in
sb->s_mode.
* With the above changes, sb->s_mode now always should contain
FMODE_EXCL. WARN_ON_ONCE() added to kill_block_super() to detect
errors.
The new blkdev_get_*() functions are with proper docbook comments.
While at it, add function description to blkdev_get() too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Joern Engel <joern@lazybastard.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: reiserfs-devel@vger.kernel.org
Cc: xfs-masters@oss.sgi.com
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Over time, block layer has accumulated a set of APIs dealing with bdev
open, close, claim and release.
* blkdev_get/put() are the primary open and close functions.
* bd_claim/release() deal with exclusive open.
* open/close_bdev_exclusive() are combination of open and claim and
the other way around, respectively.
* bd_link/unlink_disk_holder() to create and remove holder/slave
symlinks.
* open_by_devnum() wraps bdget() + blkdev_get().
The interface is a bit confusing and the decoupling of open and claim
makes it impossible to properly guarantee exclusive access as
in-kernel open + claim sequence can disturb the existing exclusive
open even before the block layer knows the current open if for another
exclusive access. Reorganize the interface such that,
* blkdev_get() is extended to include exclusive access management.
@holder argument is added and, if is @FMODE_EXCL specified, it will
gain exclusive access atomically w.r.t. other exclusive accesses.
* blkdev_put() is similarly extended. It now takes @mode argument and
if @FMODE_EXCL is set, it releases an exclusive access. Also, when
the last exclusive claim is released, the holder/slave symlinks are
removed automatically.
* bd_claim/release() and close_bdev_exclusive() are no longer
necessary and either made static or removed.
* bd_link_disk_holder() remains the same but bd_unlink_disk_holder()
is no longer necessary and removed.
* open_bdev_exclusive() becomes a simple wrapper around lookup_bdev()
and blkdev_get(). It also has an unexpected extra bdev_read_only()
test which probably should be moved into blkdev_get().
* open_by_devnum() is modified to take @holder argument and pass it to
blkdev_get().
Most of bdev open/close operations are unified into blkdev_get/put()
and most exclusive accesses are tested atomically at the open time (as
it should). This cleans up code and removes some, both valid and
invalid, but unnecessary all the same, corner cases.
open_bdev_exclusive() and open_by_devnum() can use further cleanup -
rename to blkdev_get_by_path() and blkdev_get_by_devt() and drop
special features. Well, let's leave them for another day.
Most conversions are straight-forward. drbd conversion is a bit more
involved as there was some reordering, but the logic should stay the
same.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Brown <neilb@suse.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: dm-devel@redhat.com
Cc: drbd-dev@lists.linbit.com
Cc: Leo Chen <leochen@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Joern Engel <joern@logfs.org>
Cc: reiserfs-devel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
In commit 20cb52ebd1, titled
"xfs: simplify xfs_vm_writepage" I added an assert that any !mapped and
uptodate buffers are not dirty. That asserts turns out to trigger a lot
when running fsx on filesystems with small block sizes. The reason for
that is that the assert is simply incorrect. !mapped and uptodate
just mean this buffer covers a hole, and whenever we do a set_page_dirty
we mark all blocks in the page dirty, no matter if they have data or
not. So remove the assert, and update the comment above the condition
to match reality.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
XFS does not need it's inodes to actuall be hashed in the VFS inode
cache, but we require the inode to be marked hashed for the
writeback code to work.
Insted of using insert_inode_hash, which requires a second
inode_lock roundtrip after the partial merge of the inode
scalability patches in 2.6.37-rc simply use the new hlist_add_fake
helper to mark it hashed without requiring a lock or touching a
global cache line.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Andi Kleen reported that gcc-4.5 gives lots of warnings for him
inside the XFS code. It turned out most of them are due to the
quota stubs beeing macros, and gcc now complaining about macros
evaluating to 0 that are not assigned to variables.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The filestreams code may take the iolock on the parent inode while
holding it on a child. This is the only place in XFS where we take
both the child and parent iolock, so just telling lockdep about it
is enough. The lock flag required for that was already added as
part of the ilock lockdep annotations and unused so far.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The delayed write buffer split trace currently issues a trace for
every buffer it scans. These buffers are not necessarily queued for
delayed write. Indeed, when buffers are pinned, there can be
thousands of traces of buffers that aren't actually queued for
delayed write and the ones that are are lost in the noise. Move the
trace point to record only buffers that are split out for IO to be
issued on.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The walk fails to decrement the per-ag reference count when the
non-blocking walk fails to obtain the per-ag reclaim lock, leading
to an assert failure on debug kernels when unmounting a filesystem.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
al_hreq is copied from userland. If al_hreq.buflen is not properly aligned
then xfs_attr_list will ignore the last bytes of kbuf. These bytes are
unitialized. It leads to leaking of contents of kernel stack memory.
Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
We promised to do this for 2.6.37, and the code looks stable enough to
keep that promise.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6: (24 commits)
quota: Fix possible oops in __dquot_initialize()
ext3: Update kernel-doc comments
jbd/2: fixed typos
ext2: fixed typo.
ext3: Fix debug messages in ext3_group_extend()
jbd: Convert atomic_inc() to get_bh()
ext3: Remove misplaced BUFFER_TRACE() in ext3_truncate()
jbd: Fix debug message in do_get_write_access()
jbd: Check return value of __getblk()
ext3: Use DIV_ROUND_UP() on group desc block counting
ext3: Return proper error code on ext3_fill_super()
ext3: Remove unnecessary casts on bh->b_data
ext3: Cleanup ext3_setup_super()
quota: Fix issuing of warnings from dquot_transfer
quota: fix dquot_disable vs dquot_transfer race v2
jbd: Convert bitops to buffer fns
ext3/jbd: Avoid WARN() messages when failing to write the superblock
jbd: Use offset_in_page() instead of manual calculation
jbd: Remove unnecessary goto statement
jbd: Use printk_ratelimited() in journal_alloc_journal_head()
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (52 commits)
split invalidate_inodes()
fs: skip I_FREEING inodes in writeback_sb_inodes
fs: fold invalidate_list into invalidate_inodes
fs: do not drop inode_lock in dispose_list
fs: inode split IO and LRU lists
fs: switch bdev inode bdi's correctly
fs: fix buffer invalidation in invalidate_list
fsnotify: use dget_parent
smbfs: use dget_parent
exportfs: use dget_parent
fs: use RCU read side protection in d_validate
fs: clean up dentry lru modification
fs: split __shrink_dcache_sb
fs: improve DCACHE_REFERENCED usage
fs: use percpu counter for nr_dentry and nr_dentry_unused
fs: simplify __d_free
fs: take dcache_lock inside __d_path
fs: do not assign default i_ino in new_inode
fs: introduce a per-cpu last_ino allocator
new helper: ihold()
...
This removes more dead code that was somehow missed by commit 0d99519efe
(writeback: remove unused nonblocking and congestion checks). There are
no behavior change except for the removal of two entries from one of the
ext4 tracing interface.
The nonblocking checks in ->writepages are no longer used because the
flusher now prefer to block on get_request_wait() than to skip inodes on
IO congestion. The latter will lead to more seeky IO.
The nonblocking checks in ->writepage are no longer used because it's
redundant with the WB_SYNC_NONE check.
We no long set ->nonblocking in VM page out and page migration, because
a) it's effectively redundant with WB_SYNC_NONE in current code
b) it's old semantic of "Don't get stuck on request queues" is mis-behavior:
that would skip some dirty inodes on congestion and page out others, which
is unfair in terms of LRU age.
Inspired by Christoph Hellwig. Thanks!
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: David Howells <dhowells@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: Steve French <sfrench@samba.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of always assigning an increasing inode number in new_inode
move the call to assign it into those callers that actually need it.
For now callers that need it is estimated conservatively, that is
the call is added to all filesystems that do not assign an i_ino
by themselves. For a few more filesystems we can avoid assigning
any inode number given that they aren't user visible, and for others
it could be done lazily when an inode number is actually needed,
but that's left for later patches.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Split up inode_add_to_list/__inode_add_to_list. Locking for the two
lists will be split soon so these helpers really don't buy us much
anymore.
The __ prefixes for the sb list helpers will go away soon, but until
inode_lock is gone we'll need them to distinguish between the locked
and unlocked variants.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
__block_write_begin and block_prepare_write are identical except for slightly
different calling conventions. Convert all callers to the __block_write_begin
calling conventions and drop block_prepare_write.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for-linus' of git://oss.sgi.com/xfs/xfs: (36 commits)
xfs: semaphore cleanup
xfs: Extend project quotas to support 32bit project ids
xfs: remove xfs_buf wrappers
xfs: remove xfs_cred.h
xfs: remove xfs_globals.h
xfs: remove xfs_version.h
xfs: remove xfs_refcache.h
xfs: fix the xfs_trans_committed
xfs: remove unused t_callback field in struct xfs_trans
xfs: fix bogus m_maxagi check in xfs_iget
xfs: do not use xfs_mod_incore_sb_batch for per-cpu counters
xfs: do not use xfs_mod_incore_sb for per-cpu counters
xfs: remove XFS_MOUNT_NO_PERCPU_SB
xfs: pack xfs_buf structure more tightly
xfs: convert buffer cache hash to rbtree
xfs: serialise inode reclaim within an AG
xfs: batch inode reclaim lookup
xfs: implement batched inode lookups for AG walking
xfs: split out inode walk inode grabbing
xfs: split inode AG walking into separate code for reclaim
...
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: remove in_workqueue_context()
workqueue: Clarify that schedule_on_each_cpu is synchronous
memory_hotplug: drop spurious calls to flush_scheduled_work()
shpchp: update workqueue usage
pciehp: update workqueue usage
isdn/eicon: don't call flush_scheduled_work() from diva_os_remove_soft_isr()
workqueue: add and use WQ_MEM_RECLAIM flag
workqueue: fix HIGHPRI handling in keep_working()
workqueue: add queue_work and activate_work trace points
workqueue: prepare for more tracepoints
workqueue: implement flush[_delayed]_work_sync()
workqueue: factor out start_flush_work()
workqueue: cleanup flush/cancel functions
workqueue: implement alloc_ordered_workqueue()
Fix up trivial conflict in fs/gfs2/main.c as per Tejun
Get rid of init_MUTEX[_LOCKED]() and use sema_init() instead.
(Ported to current XFS code by <aelder@sgi.com>.)
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
This patch adds support for 32bit project quota identifiers.
On disk format is backward compatible with 16bit projid numbers. projid
on disk is now kept in two 16bit values - di_projid_lo (which holds the
same position as old 16bit projid value) and new di_projid_hi (takes
existing padding) and converts from/to 32bit value on the fly.
xfs_admin (for existing fs), mkfs.xfs (for new fs) needs to be used
to enable PROJID32BIT support.
Signed-off-by: Arkadiusz Miśkiewicz <arekm@maven.pl>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Stop having two different names for many buffer functions and use
the more descriptive xfs_buf_* names directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We're not actually passing around credentials inside XFS for a while
now, so remove all xfs_cred.h with it's cred_t typedef and all
instances of it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
This header only provides one extern that isn't actually declared
anywhere, and shadowed by a macro.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
It used to have a place when it contained an automatically generated
CVS version, but these days it's entirely superflous.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Use the correct prototype for xfs_trans_committed instead of casting it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
These days inode64 should only control which AGs we allocate new
inodes from, while we still try to support reading all existing
inodes. To make this actually work the check ontop of xfs_iget
needs to be relaxed to allow inodes in all allocation groups instead
of just those that we allow allocating inodes from. Note that we
can't simply remove the check - it prevents us from accessing
invalid data when fed invalid inode numbers from NFS or bulkstat.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Update the per-cpu counters manually in xfs_trans_unreserve_and_mod_sb
and remove support for per-cpu counters from xfs_mod_incore_sb_batch
to simplify it. And added benefit is that we don't have to take
m_sb_lock for transactions that only modify per-cpu counters.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Export xfs_icsb_modify_counters and always use it for modifying
the per-cpu counters. Remove support for per-cpu counters from
xfs_mod_incore_sb to simplify it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Fail the mount if we can't allocate memory for the per-CPU counters.
This is consistent with how we handle everything else in the mount
path and makes the superblock counter modification a lot simpler.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
pahole reports the struct xfs_buf has quite a few holes in it, so
packing the structure better will reduce the size of it by 16 bytes.
Also, move all the fields used in cache lookups into the first
cacheline.
Before on x86_64:
/* size: 320, cachelines: 5 */
/* sum members: 298, holes: 6, sum holes: 22 */
After on x86_64:
/* size: 304, cachelines: 5 */
/* padding: 6 */
/* last cacheline: 48 bytes */
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
The buffer cache hash is showing typical hash scalability problems.
In large scale testing the number of cached items growing far larger
than the hash can efficiently handle. Hence we need to move to a
self-scaling cache indexing mechanism.
I have selected rbtrees for indexing becuse they can have O(log n)
search scalability, and insert and remove cost is not excessive,
even on large trees. Hence we should be able to cache large numbers
of buffers without incurring the excessive cache miss search
penalties that the hash is imposing on us.
To ensure we still have parallel access to the cache, we need
multiple trees. Rather than hashing the buffers by disk address to
select a tree, it seems more sensible to separate trees by typical
access patterns. Most operations use buffers from within a single AG
at a time, so rather than searching lots of different lists,
separate the buffer indexes out into per-AG rbtrees. This means that
searches during metadata operation have a much higher chance of
hitting cache resident nodes, and that updates of the tree are less
likely to disturb trees being accessed on other CPUs doing
independent operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Memory reclaim via shrinkers has a terrible habit of having N+M
concurrent shrinker executions (N = num CPUs, M = num kswapds) all
trying to shrink the same cache. When the cache they are all working
on is protected by a single spinlock, massive contention an
slowdowns occur.
Wrap the per-ag inode caches with a reclaim mutex to serialise
reclaim access to the AG. This will block concurrent reclaim in each
AG but still allow reclaim to scan multiple AGs concurrently. Allow
shrinkers to move on to the next AG if it can't get the lock, and if
we can't get any AG, then start blocking on locks.
To prevent reclaimers from continually scanning the same inodes in
each AG, add a cursor that tracks where the last reclaim got up to
and start from that point on the next reclaim. This should avoid
only ever scanning a small number of inodes at the satart of each AG
and not making progress. If we have a non-shrinker based reclaim
pass, ignore the cursor and reset it to zero once we are done.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Batch and optimise the per-ag inode lookup for reclaim to minimise
scanning overhead. This involves gang lookups on the radix trees to
get multiple inodes during each tree walk, and tighter validation of
what inodes can be reclaimed without blocking befor we take any
locks.
This is based on ideas suggested in a proof-of-concept patch
posted by Nick Piggin.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
With the reclaim code separated from the generic walking code, it is
simple to implement batched lookups for the generic walk code.
Separate out the inode validation from the execute operations and
modify the tree lookups to get a batch of inodes at a time.
Reclaim operations will be optimised separately.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
When doing read side inode cache walks, the code to validate and
grab an inode is common to all callers. Split it out of the execute
callbacks in preparation for batching lookups. Similarly, split out
the inode reference dropping from the execute callbacks into the
main lookup look to be symmetric with the grab.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
The reclaim walk requires different locking and has a slightly
different walk algorithm, so separate it out so that it can be
optimised separately.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
For RT and external log devices, we never use hashed buffers on them
now. Remove the buftarg hash tables that are set up for them.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
When we are checking we can access the last block of each device, we
do not need to use cached buffers as they will be tossed away
immediately. Use uncached buffers for size checks so that all IO
prior to full in-memory structure initialisation does not use the
buffer cache.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Filesystem level managed buffers are buffers that have their
lifecycle controlled by the filesystem layer, not the buffer cache.
We currently cache these buffers, which makes cleanup and cache
walking somewhat troublesome. Convert the fs managed buffers to
uncached buffers obtained by via xfs_buf_get_uncached(), and remove
the XBF_FS_MANAGED special cases from the buffer cache.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Each buffer contains both a buftarg pointer and a mount pointer. If
we add a mount pointer into the buftarg, we can avoid needing the
b_mount field in every buffer and grab it from the buftarg when
needed instead. This shrinks the xfs_buf by 8 bytes.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
To avoid the need to use cached buffers for single-shot or buffers
cached at the filesystem level, introduce a new buffer read
primitive that bypasses the cache an reads directly from disk.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
xfs_buf_get_nodaddr() is really used to allocate a buffer that is
uncached. While it is not directly assigned a disk address, the fact
that they are not cached is a more important distinction. With the
upcoming uncached buffer read primitive, we should be consistent
with this disctinction.
While there, make page allocation in xfs_buf_get_nodaddr() safe
against memory reclaim re-entrancy into the filesystem by allowing
a flags parameter to be passed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Under heavy multi-way parallel create workloads, the VFS struggles
to write back all the inodes that have been changed in age order.
The bdi flusher thread becomes CPU bound, spending 85% of it's time
in the VFS code, mostly traversing the superblock dirty inode list
to separate dirty inodes old enough to flush.
We already keep an index of all metadata changes in age order - in
the AIL - and continued log pressure will do age ordered writeback
without any extra overhead at all. If there is no pressure on the
log, the xfssyncd will periodically write back metadata in ascending
disk address offset order so will be very efficient.
Hence we can stop marking VFS inodes dirty during transaction commit
or when changing timestamps during transactions. This will keep the
inodes in the superblock dirty list to those containing data or
unlogged metadata changes.
However, the timstamp changes are slightly more complex than this -
there are a couple of places that do unlogged updates of the
timestamps, and the VFS need to be informed of these. Hence add a
new function xfs_trans_ichgtime() for transactional changes,
and leave xfs_ichgtime() for the non-transactional changes.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we start taking a reference to the per-ag for every cached
buffer in the system, kernel lockstat profiling on an 8-way create
workload shows the mp->m_perag_lock has higher acquisition rates
than the inode lock and has significantly more contention. That is,
it becomes the highest contended lock in the system.
The perag lookup is trivial to convert to lock-less RCU lookups
because perag structures never go away. Hence the only thing we need
to protect against is tree structure changes during a grow. This can
be done simply by replacing the locking in xfs_perag_get() with RCU
read locking. This removes the mp->m_perag_lock completely from this
path.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
When we start taking references per cached buffer to the the perag
it is cached on, it will blow the current debug maximum reference
count assert out of the water. The assert has never caught a bug,
and we have tracing to track changes if there ever is a problem,
so just remove it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
When commiting a transaction, we do a lock CIL state lock round trip
on every single log vector we insert into the CIL. This is resulting
in the lock being as hot as the inode and dcache locks on 8-way
create workloads. Rework the insertion loops to bring the number
of lock round trips to one per transaction for log vectors, and one
more do the busy extents.
Also change the allocation of the log vector buffer not to zero it
as we copy over the entire allocated buffer anyway.
This patch also includes a structural cleanup to the CIL item
insertion provided by Christoph Hellwig.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Ionut Gabriel Popescu <poyo_vl@yahoo.com> submitted a simple change
to eliminate some "may be used uninitialized" warnings when building
XFS. The reported condition seems to be something that GCC did not
used to recognize or report. The warnings were produced by:
gcc version 4.5.0 20100604
[gcc-4_5-branch revision 160292] (SUSE Linux)
Signed-off-by: Ionut Gabriel Popescu <poyo_vl@yahoo.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
The implementation os ->kill_root only differ by either simply
zeroing out the now unused buffer in the btree cursor in the inode
allocation btree or using xfs_btree_setbuf in the allocation btree.
Initially both of them used xfs_btree_setbuf, but the use in the
ialloc btree was removed early on because it interacted badly with
xfs_trans_binval.
In addition to zeroing out the buffer in the cursor xfs_btree_setbuf
updates the bc_ra array in the btree cursor, and calls
xfs_trans_brelse on the buffer previous occupying the slot.
The bc_ra update should be done for the alloc btree updated too,
although the lack of it does not cause serious problems. The
xfs_trans_brelse call on the other hand is effectively a no-op in
the end - it keeps decrementing the bli_recur refcount until it hits
zero, and then just skips out because the buffer will always be
dirty at this point. So removing it for the allocation btree is
just fine.
So unify the code and move it to xfs_btree.c. While we're at it
also replace the call to xfs_btree_setbuf with a NULL bp argument in
xfs_btree_del_cursor with a direct call to xfs_trans_brelse given
that the cursor is beeing freed just after this and the state
updates are superflous. After this xfs_btree_setbuf is only used
with a non-NULL bp argument and can thus be simplified.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
In xfs_qm_dqflush we know that q_blkno must be initialized already from a
previous xfs_qm_dqread. So instead of calling xfs_qm_dqtobp we can
simply read the quota buffer directly. This also saves us from a duplicate
xfs_qm_dqcheck call check and allows xfs_qm_dqtobp to be simplified now
that it is always called for a newly initialized inode. In addition to
that properly unwind all locks in xfs_qm_dqflush when xfs_qm_dqcheck
fails.
This mirrors a similar cleanup in the inode lookup done earlier.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
There is no need to have the users and group/project quota locked at the
same time. Get rid of xfs_qm_dqget_noattach and just do a xfs_qm_dqget
inside xfs_qm_quotacheck_dqadjust for the quota we are operating on
right now. The new version of xfs_qm_quotacheck_dqadjust holds the
inode lock over it's operations, which is not a problem as it simply
increments counters and there is no concern about log contention
during mount time.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
XFS_IOC_ZERO_RANGE is the equivalent of an atomic XFS_IOC_UNRESVSP/
XFS_IOC_RESVSP call pair. It enabled ranges of written data to be
turned into zeroes without requiring IO or having to free and
reallocate the extents in the range given as would occur if we had
to punch and then preallocate them separately. This enables
applications to zero parts of files very quickly without changing
the layout of the files in any way.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
While XFS passes ranges to operate on from the core code, the
functions being called ignore the either the entire range or the end
of the range. This is historical because when the function were
written linux didn't have the necessary range operations. Update the
functions to use the correct operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Add WQ_MEM_RECLAIM flag which currently maps to WQ_RESCUER, mark
WQ_RESCUER as internal and replace all external WQ_RESCUER usages to
WQ_MEM_RECLAIM.
This makes the API users express the intent of the workqueue instead
of indicating the internal mechanism used to guarantee forward
progress. This is also to make it cleaner to add more semantics to
WQ_MEM_RECLAIM. For example, if deemed necessary, memory reclaim
workqueues can be made highpri.
This patch doesn't introduce any functional change.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
When marking an inode reclaimable, a per-AG counter is increased, the
inode is tagged reclaimable in its per-AG tree, and, when this is the
first reclaimable inode in the AG, the AG entry in the per-mount tree
is also tagged.
When an inode is finally reclaimed, however, it is only deleted from
the per-AG tree. Neither the counter is decreased, nor is the parent
tree's AG entry untagged properly.
Since the tags in the per-mount tree are not cleared, the inode
shrinker iterates over all AGs that have had reclaimable inodes at one
point in time.
The counters on the other hand signal an increasing amount of slab
objects to reclaim. Since "70e60ce xfs: convert inode shrinker to
per-filesystem context" this is not a real issue anymore because the
shrinker bails out after one iteration.
But the problem was observable on a machine running v2.6.34, where the
reclaimable work increased and each process going into direct reclaim
eventually got stuck on the xfs inode shrinking path, trying to scan
several million objects.
Fix this by properly unwinding the reclaimable-state tracking of an
inode when it is reclaimed.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: stable@kernel.org
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Remove "depends on" line from QUOTACTL config option and rather select
the option explicitely from config options which need it. It makes more
sense this way and also fixes Kconfig warning due to GFS2 selecting
QUOTACTL but QUOTACTL not depending on it.
Signed-off-by: Jan Kara <jack@suse.cz>
I have been seeing occasional pauses in transaction throughput up to
30s long under heavy parallel workloads. The only notable thing was
that the xfsaild was trying to be active during the pauses, but
making no progress. It was running exactly 20 times a second (on the
50ms no-progress backoff), and the number of pushbuf events was
constant across this time as well. IOWs, the xfsaild appeared to be
stuck on buffers that it could not push out.
Further investigation indicated that it was trying to push out inode
buffers that were pinned and/or locked. The xfsbufd was also getting
woken at the same frequency (by the xfsaild, no doubt) to push out
delayed write buffers. The xfsbufd was not making any progress
because all the buffers in the delwri queue were pinned. This scan-
and-make-no-progress dance went one in the trace for some seconds,
before the xfssyncd came along an issued a log force, and then
things started going again.
However, I noticed something strange about the log force - there
were way too many IO's issued. 516 log buffers were written, to be
exact. That added up to 129MB of log IO, which got me very
interested because it's almost exactly 25% of the size of the log.
He delayed logging code is suppose to aggregate the minimum of 25%
of the log or 8MB worth of changes before flushing. That's what
really puzzled me - why did a log force write 129MB instead of only
8MB?
Essentially what has happened is that no CIL pushes had occurred
since the previous tail push which cleared out 25% of the log space.
That caused all the new transactions to block because there wasn't
log space for them, but they kick the xfsaild to push the tail.
However, the xfsaild was not making progress because there were
buffers it could not lock and flush, and the xfsbufd could not flush
them because they were pinned. As a result, both the xfsaild and the
xfsbufd could not move the tail of the log forward without the CIL
first committing.
The cause of the problem was that the background CIL push, which
should happen when 8MB of aggregated changes have been committed, is
being held off by the concurrent transaction commit load. The
background push does a down_write_trylock() which will fail if there
is a concurrent transaction commit holding the push lock in read
mode. With 8 CPUs all doing transactions as fast as they can, there
was enough concurrent transaction commits to hold off the background
push until tail-pushing could no longer free log space, and the halt
would occur.
It should be noted that there is no reason why it would halt at 25%
of log space used by a single CIL checkpoint. This bug could
definitely violate the "no transaction should be larger than half
the log" requirement and hence result in corruption if the system
crashed under heavy load. This sort of bug is exactly the reason why
delayed logging was tagged as experimental....
The fix is to start blocking background pushes once the threshold
has been exceeded. Rework the threshold calculations to keep the
amount of log space a CIL checkpoint can use to below that of the
AIL push threshold to avoid the problem completely.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
All the blkdev_issue_* helpers can only sanely be used for synchronous
caller. To issue cache flushes or barriers asynchronously the caller needs
to set up a bio by itself with a completion callback to move the asynchronous
state machine ahead. So drop the BLKDEV_IFL_WAIT flag that is always
specified when calling blkdev_issue_* and also remove the now unused flags
argument to blkdev_issue_flush and blkdev_issue_zeroout. For
blkdev_issue_discard we need to keep it for the secure discard flag, which
gains a more descriptive name and loses the bitops vs flag confusion.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
The workqueue implementation in 2.6.36-rcX has changed, resulting
in the workqueues no longer having dedicated threads for work
processing. This has caused severe livelocks under heavy parallel
create workloads because the log IO completions have been getting
held up behind metadata IO completions. Hence log commits would
stall, memory allocation would stall because pages could not be
cleaned, and lock contention on the AIL during inode IO completion
processing was being seen to slow everything down even further.
By making the log Io completion workqueue a high priority workqueue,
they are queued ahead of all data/metadata IO completions and
processed before the data/metadata completions. Hence the log never
gets stalled, and operations needed to clean memory can continue as
quickly as possible. This avoids the livelock conditions and allos
the system to keep running under heavy load as per normal.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The XFS_IOC_FSGETXATTR ioctl allows unprivileged users to read 12
bytes of uninitialized stack memory, because the fsxattr struct
declared on the stack in xfs_ioc_fsgetxattr() does not alter (or zero)
the 12-byte fsx_pad member before copying it back to the user. This
patch takes care of it.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Switch to the WRITE_FLUSH_FUA flag for log writes and remove the EOPNOTSUPP
detection for barriers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
In xfs_vn_fiemap, we set bvm_count to fi_extent_max + 1 and want
to return fi_extent_max extents, but actually it won't work for
a sparse file. The reason is that in xfs_getbmap we will
calculate holes and set it in 'out', while out is malloced by
bmv_count(fi_extent_max+1) which didn't consider holes. So in the
worst case, if 'out' vector looks like
[hole, extent, hole, extent, hole, ... hole, extent, hole],
we will only return half of fi_extent_max extents.
This patch add a new parameter BMV_IF_NO_HOLES for bvm_iflags.
So with this flags, we don't use our 'out' in xfs_getbmap for
a hole. The solution is a bit ugly by just don't increasing
index of 'out' vector. I felt that it is not easy to skip it
at the very beginning since we have the complicated check and
some function like xfs_getbmapx_fix_eof_hole to adjust 'out'.
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
If we attempt to preallocate more than 2^32 blocks of space in a
single syscall, the transaction block reservation will overflow
leading to a hangs in the superblock block accounting code. This
is trivially reproduced with xfs_io. Fix the problem by capping the
allocation reservation to the maximum number of blocks a single
xfs_bmapi() call can allocate (2^21 blocks).
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Currently on-disk structure is able to keep only 16bit project quota
id, so disallow 32bit ones. This fixes a problem where parts of
kernel structures holding project quota id are 32bit while parts
(on-disk) are 16bit variables which causes project quota member
files to be inaccessible for some operations (like mv/rm).
Signed-off-by: Arkadiusz Mi?kiewicz <arekm@maven.pl>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
When doing large parallel file creates on a 16p machines, large amounts of
time is being spent in _xfs_buf_find(). A system wide profile with perf top
shows this:
1134740.00 19.3% _xfs_buf_find
733142.00 12.5% __ticket_spin_lock
The problem is that the hash contains 45,000 buffers, and the hash table width
is only 256 buffers. That means we've got around 200 buffers per chain, and
searching it is quite expensive. The hash table size needs to increase.
Secondly, every time we do a lookup, we promote the buffer we find to the head
of the hash chain. This is causing cachelines to be dirtied and causes
invalidation of cachelines across all CPUs that may have walked the hash chain
recently. hence every walk of the hash chain is effectively a cold cache walk.
Remove the promotion to avoid this invalidation.
The results are:
1045043.00 21.2% __ticket_spin_lock
326184.00 6.6% _xfs_buf_find
A 70% drop in the CPU usage when looking up buffers. Unfortunately that does
not result in an increase in performance underthis workload as contention on
the inode_lock soaks up most of the reduction in CPU usage.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If xfs_map_blocks returns EAGAIN because of lock contention we must redirty the
page and not disard the pagecache content and return an error from writepage.
We used to do this correctly, but the logic got lost during the recent
reshuffle of the writepage code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Mike Gao <ygao.linux@gmail.com>
Tested-by: Mike Gao <ygao.linux@gmail.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Formatting items requires memory allocation when using delayed
logging. Currently that memory allocation is done while holding the
CIL context lock in read mode. This means that if memory allocation
takes some time (e.g. enters reclaim), we cannot push on the CIL
until the allocation(s) required by formatting complete. This can
stall CIL pushes for some time, and once a push is stalled so are
all new transaction commits.
Fix this splitting the item formatting into two steps. The first
step which does the allocation and memcpy() into the allocated
buffer is now done outside the CIL context lock, and only the CIL
insert is done inside the CIL context lock. This avoids the stall
issue.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Delayed logging adds some serialisation to the log force process to
ensure that it does not deference a bad commit context structure
when determining if a CIL push is necessary or not. It does this by
grabing the CIL context lock exclusively, then dropping it before
pushing the CIL if necessary. This causes serialisation of all log
forces and pushes regardless of whether a force is necessary or not.
As a result fsync heavy workloads (like dbench) can be significantly
slower with delayed logging than without.
To avoid this penalty, copy the current sequence from the context to
the CIL structure when they are swapped. This allows us to do
unlocked checks on the current sequence without having to worry
about dereferencing context structures that may have already been
freed. Hence we can remove the CIL context locking in the forcing
code and only call into the push code if the current context matches
the sequence we need to force.
By passing the sequence into the push code, we can check the
sequence again once we have the CIL lock held exclusive and abort if
the sequence has already been pushed. This avoids a lock round-trip
and unnecessary CIL pushes when we have racing push calls.
The result is that the regression in dbench performance goes away -
this change improves dbench performance on a ramdisk from ~2100MB/s
to ~2500MB/s. This compares favourably to not using delayed logging
which retuns ~2500MB/s for the same workload.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we need to cover the log, we issue dummy transactions to ensure
the current log tail is on disk. Unfortunately we currently use the
root inode in the dummy transaction, and the act of committing the
transaction dirties the inode at the VFS level.
As a result, the VFS writeback of the dirty inode will prevent the
filesystem from idling long enough for the log covering state
machine to complete. The state machine gets stuck in a loop issuing
new dummy transactions to cover the log and never makes progress.
To avoid this problem, the dummy transactions should not cause
externally visible state changes. To ensure this occurs, make sure
that dummy transactions log an unchanging field in the superblock as
it's state is never propagated outside the filesystem. This allows
the log covering state machine to complete successfully and the
filesystem now correctly enters a fully idle state about 90s after
the last modification was made.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Because of delayed updates to sb_icount field in the super block, it
is possible to allocate over maxicount number of inodes. This
causes the arithmetic to calculate a negative number of free inodes
in user commands like df or stat -f.
Since maxicount is a somewhat arbitrary number, a slight over
allocation is not critical but user commands should be displayed as
0 or greater and never go negative. To do this the value in the
stats buffer f_ffree is capped to never go negative.
[ Modified to use max_t as per Christoph's comment. ]
Signed-off-by: Stu Brodsky <sbrodsky@sgi.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
During data integrity (WB_SYNC_ALL) writeback, wbc->nr_to_write will
go negative on inodes with more than 1024 dirty pages due to
implementation details of write_cache_pages(). Currently XFS will
abort page clustering in writeback once nr_to_write drops below
zero, and so for data integrity writeback we will do very
inefficient page at a time allocation and IO submission for inodes
with large numbers of dirty pages.
Fix this by only aborting the page clustering code when
wbc->nr_to_write is negative and the sync mode is WB_SYNC_NONE.
Cc: <stable@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Commit 7124fe0a5b ("xfs: validate untrusted inode
numbers during lookup") changes the inode lookup code to do btree lookups for
untrusted inode numbers. This change made an invalid assumption about the
alignment of inodes and hence incorrectly calculated the first inode in the
cluster. As a result, some inode numbers were being incorrectly considered
invalid when they were actually valid.
The issue was not picked up by the xfstests suite because it always runs fsr
and dump (the two utilities that utilise the bulkstat interface) on cache hot
inodes and hence the lookup code in the cold cache path was not sufficiently
exercised to uncover this intermittent problem.
Fix the issue by relaxing the btree lookup criteria and then checking if the
record returned contains the inode number we are lookup for. If it we get an
incorrect record, then the inode number is invalid.
Cc: <stable@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Under heavy load parallel metadata loads (e.g. dbench), we can fail
to mark all the inodes in a cluster being freed as XFS_ISTALE as we
skip inodes we cannot get the XFS_ILOCK_EXCL or the flush lock on.
When this happens and the inode cluster buffer has already been
marked stale and freed, inode reclaim can try to write the inode out
as it is dirty and not marked stale. This can result in writing th
metadata to an freed extent, or in the case it has already
been overwritten trigger a magic number check failure and return an
EUCLEAN error such as:
Filesystem "ram0": inode 0x442ba1 background reclaim flush failed with 117
Fix this by ensuring that we hoover up all in memory inodes in the
cluster and mark them XFS_ISTALE when freeing the cluster.
Cc: <stable@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we commit a transaction using delayed logging, we need to
unlock the items in the transaciton before we unlock the CIL context
and allow it to be checkpointed. If we unlock them after we release
the CIl context lock, the CIL can checkpoint and complete before
we free the log items. This breaks stale buffer item unlock and
unpin processing as there is an implicit assumption that the unlock
will occur before the unpin.
Also, some log items need to store the LSN of the transaction commit
in the item (inodes and EFIs) and so can race with other transaction
completions if we don't prevent the CIL from checkpointing before
the unlock occurs.
Cc: <stable@kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
no need for list_for_each_entry_safe()/resetting with superblock list
Fix sget() race with failing mount
vfs: don't hold s_umount over close_bdev_exclusive() call
sysv: do not mark superblock dirty on remount
sysv: do not mark superblock dirty on mount
btrfs: remove junk sb_dirt change
BFS: clean up the superblock usage
AFFS: wait for sb synchronization when needed
AFFS: clean up dirty flag usage
cifs: truncate fallout
mbcache: fix shrinker function return value
mbcache: Remove unused features
add f_flags to struct statfs(64)
pass a struct path to vfs_statfs
update VFS documentation for method changes.
All filesystems that need invalidate_inode_buffers() are doing that explicitly
convert remaining ->clear_inode() to ->evict_inode()
Make ->drop_inode() just return whether inode needs to be dropped
fs/inode.c:clear_inode() is gone
fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
...
Fix up trivial conflicts in fs/nilfs2/super.c
add I_CLEAR instead of replacing I_FREEING with it. I_CLEAR is
equivalent to I_FREEING for almost all code looking at either;
it's there to keep track of having called clear_inode() exactly
once per inode lifetime, at some point after having set I_FREEING.
I_CLEAR and I_FREEING never get set at the same time with the
current code, so we can switch to setting i_flags to I_FREEING | I_CLEAR
instead of I_CLEAR without loss of information. As the result of
such change, checks become simpler and the amount of code that needs
to know about I_CLEAR shrinks a lot.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Convert XFS to the new truncate sequence. We still can have errors after
updating the file size in xfs_setattr, but these are real I/O errors and lead
to a transaction abort and filesystem shutdown, so they are not an issue.
Errors from ->write_begin and write_end can now be handled correctly because
we can actually get rid of the delalloc extents while previous the buffer
state was stipped in block_invalidatepage.
There is still no error handling for ->direct_IO, because doing so will need
some major restructuring given that we only have the iolock shared and do not
hold i_mutex at all. Fortunately leaving the normally allocated blocks behind
there is not a major issue and this will get cleaned up by xfs_free_eofblock
later.
Note: the patch is against Al's vfs.git tree as that contains the nessecary
preparations. I'd prefer to get it applied there so that we can get some
testing in linux-next.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Move the call to vmtruncate to get rid of accessive blocks to the callers
in preparation of the new truncate sequence and rename the non-truncating
version to block_write_begin.
While we're at it also remove several unused arguments to block_write_begin.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Move the call to vmtruncate to get rid of accessive blocks to the callers
in prepearation of the new truncate calling sequence. This was only done
for DIO_LOCKING filesystems, so the __blockdev_direct_IO_newtrunc variant
was not needed anyway. Get rid of blockdev_direct_IO_no_locking and
its _newtrunc variant while at it as just opencoding the two additional
paramters is shorted than the name suffix.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
ext3: Fix dirtying of journalled buffers in data=journal mode
ext3: default to ordered mode
quota: Use mark_inode_dirty_sync instead of mark_inode_dirty
quota: Change quota error message to print out disk and function name
MAINTAINERS: Update entries of ext2 and ext3
MAINTAINERS: Update address of Andreas Dilger
ext3: Avoid filesystem corruption after a crash under heavy delete load
ext3: remove vestiges of nobh support
ext3: Fix set but unused variables
quota: clean up quota active checks
quota: Clean up the namespace in dqblk_xfs.h
quota: check quota reservation on remove_dquot_ref
Our current handling of direct I/O completions is rather suboptimal,
because we defer it to a workqueue more often than needed, and we
perform a much to aggressive flush of the workqueue in case unwritten
extent conversions happen.
This patch changes the direct I/O reads to not even use a completion
handler, as we don't bother to use it at all, and to perform the unwritten
extent conversions in caller context for synchronous direct I/O.
For a small I/O size direct I/O workload on a consumer grade SSD, such as
the untar of a kernel tree inside qemu this patch gives speedups of
about 5%. Getting us much closer to the speed of a native block device,
or a fully allocated XFS file.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
If we write into an unwritten extent using AIO we need to complete the AIO
request after the extent conversion has finished. Without that a read could
race to see see the extent still unwritten and return zeros. For synchronous
I/O we already take care of that by flushing the xfsconvertd workqueue (which
might be a bit of overkill).
To do that add iocb and result fields to struct xfs_ioend, so that we can
call aio_complete from xfs_end_io after the extent conversion has happened.
Note that we need a new result field as io_error is used for positive errno
values, while the AIO code can return negative error values and positive
transfer sizes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Filesystems with unwritten extent support must not complete an AIO request
until the transaction to convert the extent has been commited. That means
the aio_complete calls needs to be moved into the ->end_io callback so
that the filesystem can control when to call it exactly.
This makes a bit of a mess out of dio_complete and the ->end_io callback
prototype even more complicated.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Alex Elder <aelder@sgi.com>
Commit 0fd7275cc42ab734eaa1a2c747e65479bd1e42af ("xfs: fix gcc 4.6
set but not read and unused statement warnings") failed to convert
some code inside XFS_NATIVE_HOST (big endian host code only) and
hence fails to build on such machines. Fix it.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
xfs_truncate_file is only used for truncating quota files. Move it to
xfs_qm_syscalls.c so it can be marked static and take advatange of the
fact by removing the unused page cache validation and taking the iget
into the helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The b_strat callback is used by xfs_buf_iostrategy to perform additional
checks before submitting a buffer. It is used in xfs_bwrite and when
writing out delayed buffers. In xfs_bwrite it we can de-virtualize the
call easily as b_strat is set a few lines above the call to
xfs_buf_iostrategy. For the delayed buffers the rationale is a bit
more complicated:
- there are three callers of xfs_buf_delwri_queue, which places buffers
on the delwri list:
(1) xfs_bdwrite - this sets up b_strat, so it's fine
(2) xfs_buf_iorequest. None of the callers can have XBF_DELWRI set:
- xlog_bdstrat is only used for log buffers, which are never delwri
- _xfs_buf_read explicitly clears the delwri flag
- xfs_buf_iodone_work retries log buffers only
- xfsbdstrat - only used for reads, superblock writes without the
delwri flag, log I/O and file zeroing with explicitly allocated
buffers.
- xfs_buf_iostrategy - only calls xfs_buf_iorequest if b_strat is
not set
(3) xfs_buf_unlock
- only puts the buffer on the delwri list if the DELWRI flag is
already set. The DELWRI flag is only ever set in xfs_bwrite,
xfs_buf_iodone_callbacks, or xfs_trans_log_buf. For
xfs_buf_iodone_callbacks and xfs_trans_log_buf we require
an initialized buf item, which means b_strat was set to
xfs_bdstrat_cb in xfs_buf_item_init.
Conclusion: we can just get rid of the callback and replace it with
explicit calls to xfs_bdstrat_cb.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Since Linux 2.6.33 the kernel has support for real O_SYNC, which made
the osyncisosync option a no-op. Warn the users about this and remove
the mount flag for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Move xfs_filestream_peek_ag, xxfs_filestream_get_ag and xfs_filestream_put_ag
from xfs_filestream.h to xfs_filestream.c where it's only callers are, and
remove the inline marker while we're at it to let the compiler decide on the
inlining. Also don't return a value from xfs_filestream_put_ag because
we don't need it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
[hch: dropped a few hunks that need structural changes instead]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When CONFIG_XFS_POSIX_ACL is not set "xfs_check_acl" is #defined
to NULL - which breaks the code attempting to add a tracepoint
on this function.
Only define the tracepoint when the function exists.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
map_len is unsigned. Checking map_len <= 0 is buggy when it should be
below zero. So, check exact expression instead of map_len.
Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Avoid a lockdep warning by preventing page cache allocation from
recursing back into the filesystem during memory reclaim.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Calling into memory reclaim with a locked inode buffer can deadlock
if memory reclaim tries to lock the inode buffer during inode
teardown. Convert the relevant memory allocations to use KM_NOFS to
avoid this deadlock condition.
Reported-by: Peter Watkins <treestem@gmail.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_ireclaim has to get and put te pag structure because it is only
called with the inode to reclaim. The one caller of this function
already has a reference on the pag and a pointer to is, so move the
radix tree delete to the caller and remove xfs_ireclaim completely.
This avoids a xfs_perag_get/put on every inode being reclaimed.
The overhead was noticed in a bug report at:
https://bugzilla.kernel.org/show_bug.cgi?id=16348
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_buf_read() fails to detect dispatch errors before attempting to
wait on sychronous IO. If there was an error, it will get stuck
forever, waiting for an I/O that was never started. Make sure the
error is detected correctly.
Further, such a failure can leave locked pages in the page cache
which will cause a later operation to hang on the page. Ensure that
we correctly process pages in the buffers when we get a dispatch
error.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
I missed Dave Chinner's second revision of this change, and pushed
his first version out to the repository instead.
commit a476c59ebb279d738718edc0e3fb76aab3687114
Author: Dave Chinner <dchinner@redhat.com>
This commit compensates for that by moving a block of code up a bit
further, with a result that matches the the effect of Dave's second
version.
Dave's first version was:
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Dave's second version was:
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
The open_exec file operation is only added by the external dmapi
patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
These days we always have buffers thanks to ->page_mkwrite. And we
already have an assert a few lines above tripping in case that was
not true due to a bug.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
We do need a barrier for the first buffer of a split log write.
Otherwise we might incorrectly stamp the tail LSN into transactions
in the first part of the split write, or not flush data I/O before
updating the inode size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Currently we don't remove the XFS mount from the shrinker list until
late in the unmount path. By this time, we have already torn down
the internals of the filesystem (e.g. the per-ag structures), and
hence if the shrinker is executed between the teardown and the
unregistering, the shrinker will get NULL per-ag structure pointers
and panic trying to dereference them.
Fix this by removing the xfs mount from the shrinker list before
tearing down it's internal structures.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
Replace the xfs_itrace_entry catchall with specific trace points. For
most simple callers we now use the simple inode class, which used to
be the iget class, but add more details tracing for namespace events,
which now includes the name of the directory entries manipulated.
Remove the xfs_inactive trace point, which is a duplicate of the clear_inode
one, and the xfs_change_file_space trace point, which is immediately
followed by the more specific alloc/free space trace points.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
xfs_iput is just a small wrapper for xfs_iunlock + IRELE. Having this
out of line wrapper means the trace events in those two can't track
their caller properly. So just remove the wrapper and opencode the
unlock + rele in the few callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
We never get an i_mode of 0 or a locked VFS inode until we pass in the
XFS_IGET_CREATE flag to xfs_iget, which makes xfs_iput_new equivalent to
xfs_iput for the only caller. In addition to that xfs_nfs_get_inode
does not even need to lock the inode given that the generation never changes
for a life inode, so just pass a 0 lock_flags to xfs_iget and release
the inode using IRELE in the error path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The xfs_iget_alloc/found tracepoints are a bit misnamed and misplaced.
Rename them to xfs_iget_hit/xfs_iget_miss and move them to the beggining
of the xfs_iget_cache_hit/miss functions. Add a new xfs_iget_reclaim_fail
tracepoint for the case where we fail to re-initialize a VFS inode,
and add a second instance of the xfs_iget_skip tracepoint for the case
of a failed igrab() call.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The tracing code can't print flags defined as enums. Most flags that
we want to print are defines as macros already, but move the few remaining
ones over to make the trace output more useful.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
On the final put of a superblock the VFS already calls sync_filesystem
for us to write out all data and wait for it. No need to start another
asynchronous writeback inside ->put_super.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Remove the flags argument to __xfs_get_blocks as we can easily derive
it from the direct argument, and remove the unused BMAPI_MMAP flag.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
xfs_iomap passes a xfs_bmbt_irec pointer to xfs_iomap_write_direct and
xfs_iomap_write_allocate to give them the results of our read-only
xfs_bmapi query. Instead of allocating a new xfs_bmbt_irec on stack
for the next call to xfs_bmapi re use the one we got passed as it's not
used after this point.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
We already rely on the fact that the sync code will cause a synchronous
log force later on (currently via xfs_fs_sync_fs -> xfs_quiesce_data ->
xfs_sync_data), so no need to do this here. This allows us to avoid
a lot of synchronous log forces during sync, which pays of especially
with delayed logging enabled. Some compilebench numbers that show
this:
xfs (delayed logging, 256k logbufs)
===================================
intial create 25.94 MB/s 25.75 MB/s 25.64 MB/s
create 8.54 MB/s 9.12 MB/s 9.15 MB/s
patch 2.47 MB/s 2.47 MB/s 3.17 MB/s
compile 29.65 MB/s 30.51 MB/s 27.33 MB/s
clean 90.92 MB/s 98.83 MB/s 128.87 MB/s
read tree 11.90 MB/s 11.84 MB/s 8.56 MB/s
read compiled 28.75 MB/s 29.96 MB/s 24.25 MB/s
delete tree 8.39 seconds 8.12 seconds 8.46 seconds
delete compiled 8.35 seconds 8.44 seconds 5.11 seconds
stat tree 6.03 seconds 5.59 seconds 5.19 seconds
stat compiled tree 9.00 seconds 9.52 seconds 8.49 seconds
xfs + write_inode log_force removal
===================================
intial create 25.87 MB/s 25.76 MB/s 25.87 MB/s
create 15.18 MB/s 14.80 MB/s 14.94 MB/s
patch 3.13 MB/s 3.14 MB/s 3.11 MB/s
compile 36.74 MB/s 37.17 MB/s 36.84 MB/s
clean 226.02 MB/s 222.58 MB/s 217.94 MB/s
read tree 15.14 MB/s 15.02 MB/s 15.14 MB/s
read compiled tree 29.30 MB/s 29.31 MB/s 29.32 MB/s
delete tree 6.22 seconds 6.14 seconds 6.15 seconds
delete compiled tree 5.75 seconds 5.92 seconds 5.81 seconds
stat tree 4.60 seconds 4.51 seconds 4.56 seconds
stat compiled tree 4.07 seconds 3.87 seconds 3.96 seconds
In addition to that also remove the delwri inode flush that is unessecary
now that bulkstat is always coherent.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The writepage implementation in XFS still tries to deal with dirty but
unmapped buffers which used to caused by writes through shared mmaps. Since
the introduction of ->page_mkwrite these can't happen anymore, so remove the
code dealing with them.
Note that the all_bh variable which causes us to start I/O on all buffers on
the pages was controlled by the count of unmapped buffers, which also
included those not actually dirty. It's now unconditionally initialized to
0 but set to 1 for the case of small file size extensions. It probably can
be removed entirely, but that's left for another patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Currently the xfs releasepage implementation has code to deal with converting
delayed allocated and unwritten space. But we never get called for those as
we always convert delayed and unwritten space when cleaning a page, or drop
the state from the buffers in block_invalidatepage. We still keep a WARN_ON
on those cases for now, but remove all the case dealing with it, which allows
to fold xfs_page_state_convert into xfs_vm_writepage and remove the !startio
case from the whole writeback path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
xfstests 194 first truncats a file back and then extends it again by
truncating it to a larger size. This causes discard_buffer to drop
the mapped, but not the uptodate bit and thus creates something that
xfs_page_state_convert takes for unmapped space created by mmap because
it doesn't check for the dirty bit, which also gets cleared by
discard_buffer and checked by other ->writepage implementations like
block_write_full_page. Handle this kind of buffers early, and unlike
Eric's first version of the patch simply ASSERT that the buffers is
dirty, given that the mmap write case can't happen anymore since the
introduction of ->page_mkwrite. The now dead code dealing with that
will be deleted in a follow on patch.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This code was introduced four years ago in commit
3e57ecf640 without any review and has
been unused since. Remove it just as the rest of the code introduced
in that commit to reduce that stack usage and complexity in this central
piece of code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
By making this member a void pointer we can get rid of a lot of pointless
casts.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Currently we need to either call IHOLD or xfs_trans_ihold on an inode when
joining it to a transaction via xfs_trans_ijoin.
This patches instead makes xfs_trans_ijoin usable on it's own by doing
an implicity xfs_trans_ihold, which also allows us to drop the third
argument. For the case where we want to hold a reference on the inode
a xfs_trans_ijoin_ref wrapper is added which does the IHOLD and marks
the inode for needing an xfs_iput. In addition to the cleaner interface
to the caller this also simplifies the implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Get rid of the xfs_buf_pin/xfs_buf_unpin/xfs_buf_ispin helpers and opencode
them in their only callers, just like we did for the inode pinning a while
ago. Also remove duplicate trace points - the bufitem tracepoints cover
all the information that is present in a buffer tracepoint.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Stop the function pointer casting madness and give all the li_cb instances
correct prototype.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Stop the function pointer casting madness and give all the xfs_item_ops the
correct prototypes.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The unpin_remove item operation instances always share most of the
implementation with the respective unpin implementation. So instead
of keeping two different entry points add a remove flag to the unpin
operation and share the code more easily.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Currently we track log item descriptor belonging to a transaction using a
complex opencoded chunk allocator. This code has been there since day one
and seems to work around the lack of an efficient slab allocator.
This patch replaces it with dynamically allocated log item descriptors
from a dedicated slab pool, linked to the transaction by a linked list.
This allows to greatly simplify the log item descriptor tracking to the
point where it's just a couple hundred lines in xfs_trans.c instead of
a separate file. The external API has also been simplified while we're
at it - the xfs_trans_add_item and xfs_trans_del_item functions to add/
delete items from a transaction have been simplified to the bare minium,
and the xfs_trans_find_item function is replaced with a direct dereference
of the li_desc field. All debug code walking the list of log items in
a transaction is down to a simple list_for_each_entry.
Note that we could easily use a singly linked list here instead of the
double linked list from list.h as the fastpath only does deletion from
sequential traversal. But given that we don't have one available as
a library function yet I use the list.h functions for simplicity.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Dmapi support was never merged upstream, but we still have a lot of hooks
bloating XFS for it, all over the fast pathes of the filesystem.
This patch drops over 700 lines of dmapi overhead. If we'll ever get HSM
support in mainline at least the namespace events can be done much saner
in the VFS instead of the individual filesystem, so it's not like this
is much help for future work.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Almost all identifiers use the FS_* namespace, so rename the missing few
XFS_* ones to FS_* as well. Without this some people might get upset
about having too many XFS names in generic code.
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
https://bugzilla.kernel.org/show_bug.cgi?id=16348
When the filesystem grows to a large number of allocation groups,
the summing of recalimable inodes gets expensive. In many cases,
most AGs won't have any reclaimable inodes and so we are wasting CPU
time aggregating over these AGs. This is particularly important for
the inode shrinker that gets called frequently under memory
pressure.
To avoid the overhead, track AGs with reclaimable inodes in the
per-ag radix tree so that we can find all the AGs with reclaimable
inodes via a simple gang tag lookup. This involves setting the tag
when the first reclaimable inode is tracked in the AG, and removing
the tag when the last reclaimable inode is removed from the tree.
Then the summation process becomes a loop walking the radix tree
summing AGs with the reclaim tag set.
This significantly reduces the overhead of scanning - a 6400 AG
filesystea now only uses about 25% of a cpu in kswapd while slab
reclaim progresses instead of being permanently stuck at 100% CPU
and making little progress. Clean filesystems filesystems will see
no overhead and the overhead only increases linearly with the number
of dirty AGs.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now the shrinker passes us a context, wire up a shrinker context per
filesystem. This allows us to remove the global mount list and the
locking problems that introduced. It also means that a shrinker call
does not need to traverse clean filesystems before finding a
filesystem with reclaimable inodes. This significantly reduces
scanning overhead when lots of filesystems are present.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The block number comes from bulkstat based inode lookups to shortcut
the mapping calculations. We ar enot able to trust anything from
bulkstat, so drop the block number as well so that the correct
lookups and mappings are always done.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Inode numbers may come from somewhere external to the filesystem
(e.g. file handles, bulkstat information) and so are inherently
untrusted. Rename the flag we use for these lookups to make it
obvious we are doing a lookup of an untrusted inode number and need
to verify it completely before trying to read it from disk.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When we decode a handle or do a bulkstat lookup, we are using an
inode number we cannot trust to be valid. If we are deleting inode
chunks from disk (default noikeep mode), then we cannot trust the on
disk inode buffer for any given inode number to correctly reflect
whether the inode has been unlinked as the di_mode nor the
generation number may have been updated on disk.
This is due to the fact that when we delete an inode chunk, we do
not write the clusters back to disk when they are removed - instead
we mark them stale to avoid them being written back potentially over
the top of something that has been subsequently allocated at that
location. The result is that we can have locations of disk that look
like they contain valid inodes but in reality do not. Hence we
cannot simply convert the inode number to a block number and read
the location from disk to determine if the inode is valid or not.
As a result, and XFS_IGET_BULKSTAT lookup needs to actually look the
inode up in the inode allocation btree to determine if the inode
number is valid or not.
It should be noted even on ikeep filesystems, there is the
possibility that blocks on disk may look like valid inode clusters.
e.g. if there are filesystem images hosted on the filesystem. Hence
even for ikeep filesystems we really need to validate that the inode
number is valid before issuing the inode buffer read.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
The non-coherent bulkstat versionsthat look directly at the inode
buffers causes various problems with performance optimizations that
make increased use of just logging inodes. This patch makes bulkstat
always use iget, which should be fast enough for normal use with the
radix-tree based inode cache introduced a while ago.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
This patch prevents user "foo" from using the SWAPEXT ioctl to swap
a write-only file owned by user "bar" into a file owned by "foo" and
subsequently reading it. It does so by checking that the file
descriptors passed to the ioctl are also opened for reading.
Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that the background flush code has been fixed, we shouldn't need to
silently multiply the wbc->nr_to_write to get good writeback. Remove
that code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use rwsem_is_locked to make the assertations for shared locks work.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Allowing writeback from reclaim context causes massive problems with stack
overflows as we can call into the writeback code which tends to be a heavy
stack user both in the generic code and XFS from random contexts that
perform memory allocations.
Follow the example of btrfs (and in slightly different form ext4) and refuse
to write out data from reclaim context. This issue should really be handled
by the VM so that we can tune better for this case, but until we get it
sorted out there we have to hack around this in each filesystem with a
complex writeback path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
When an inode cluster is freed, it needs to mark all inodes in memory as
XFS_ISTALE before marking the buffer as stale. This is eeded because the inodes
have a different life cycle to the buffer, and once the buffer is torn down
during transaction completion, we must ensure none of the inodes get written
back (which is what XFS_ISTALE does).
Unfortunately, xfs_ifree_cluster() has some bugs that lead to inodes not being
marked with XFS_ISTALE. This shows up when xfs_iflush() is called on these
inodes either during inode reclaim or tail pushing on the AIL. The buffer is
read back, but no longer contains inodes and so triggers assert failures and
shutdowns. This was reproducable with at run.dbench10 invocation from xfstests.
There are two main causes of xfs_ifree_cluster() failing. The first is simple -
it checks in-memory inodes it finds in the per-ag icache to see if they are
clean without holding the flush lock. if they are clean it skips them
completely. However, If an inode is flushed delwri, it will
appear clean, but is not guaranteed to be written back until the flush lock has
been dropped. Hence we may have raced on the clean check and the inode may
actually be dirty. Hence always mark inodes found in memory stale before we
check properly if they are clean.
The second is more complex, and makes the first problem easier to hit.
Basically the in-memory inode scan is done with full knowledge it can be racing
with inode flushing and AIl tail pushing, which means that inodes that it can't
get the flush lock on might not be attached to the buffer after then in-memory
inode scan due to IO completion occurring. This is actually documented in the
code as "needs better interlocking". i.e. this is a zero-day bug.
Effectively, the in-memory scan must be done while the inode buffer is locked
and Io cannot be issued on it while we do the in-memory inode scan. This
ensures that inodes we couldn't get the flush lock on are guaranteed to be
attached to the cluster buffer, so we can then catch all in-memory inodes and
mark them stale.
Now that the inode cluster buffer is locked before the in-memory scan is done,
there is no need for the two-phase update of the in-memory inodes, so simplify
the code into two loops and remove the allocation of the temporary buffer used
to hold locked inodes across the phases.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
If a filesystem is mounted without the inode64 mount option we
should still be able to access inodes not fitting into 32 bits, just
not created new ones. For this to work we need to make sure the
inode cache radix tree is initialized for all allocation groups, not
just those we plan to allocate inodes from. This patch makes sure
we initialize the inode cache radix tree for all allocation groups,
and also cleans xfs_initialize_perag up a bit to separate the
inode32 logical from the general perag structure setup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The use of radix_tree_preload() only works if the radix tree was
initialised without the __GFP_WAIT flag. The per-ag tree uses
GFP_NOFS, so does not trigger allocation of new tree nodes from the
preloaded array. Hence it enters the allocator with a spinlock held
and triggers the might_sleep() warnings.
Reported-by; Chris Mason <chris.mason@oracle.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Add a mutex_unlock missing on the error path. The use of this lock
is balanced elsewhere in the file.
The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)
// <smpl>
@@
expression E1;
@@
* mutex_lock(E1,...);
<+... when != E1
if (...) {
... when != E1
* return ...;
}
...+>
* mutex_unlock(E1,...);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Alex Elder <aelder@sgi.com>
Use DECLARE_EVENT_CLASS, and save ~15K:
text data bss dec hex filename
171949 43028 48 215025 347f1 fs/xfs/linux-2.6/xfs_trace.o.orig
156521 43028 36 199585 30ba1 fs/xfs/linux-2.6/xfs_trace.o
No change in functionality.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Alex Elder <aelder@sgi.com>
The new xfsqa test 228 tries to preallocate more space than the
filesystem contains. it should fail, but instead triggers an assert
about lock flags. The failure is due to the size extension failing
in vmtruncate() due to rlimit being set. Check this before we start
the preallocation to avoid allocating space that will never be used.
Also the path through xfs_vn_allocate already holds the IO lock, so
it should not be present in the lock flags when the setattr fails.
Hence the assert needs to take this into account. This will prevent
other such callers from hitting this incorrect ASSERT.
(Fixed a reference to "newsize" to read "new_size". -Alex)
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Add suggested cleanups to commit 29db3370a1369541d58d692fbfb168b8a0bd7f41
from review that didn't end up being commited.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Instead of having small helper functions calling big macros do the
calculations for the log reservations directly in the functions.
These are mostly 1:1 from the macros execept that the macros kept
the quota calculations in their callers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Recent testers were slightly confused that a realtime mount failed
due to missing CONFIG_XFS_RT; we can make that a little more
obvious.
V2: drop the else as suggested by Christoph
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Many places in the xfs code return E2BIG when they really mean
EFBIG; trying to grow past 16T on a 32 bit machine, for example,
says "Argument list too long" rather than "File too large" which is
not particularly helpful.
Some of these don't make perfect sense as EFBIG either, but still
better than E2BIG IMHO.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
With delayed logging, we can get inode allocation buffers in the
same transaction inode unlink buffers. We don't currently mark inode
allocation buffers in the log, so inode unlink buffers take
precedence over allocation buffers.
The result is that when they are combined into the same checkpoint,
only the unlinked inode chain fields are replayed, resulting in
uninitialised inode buffers being detected when the next inode
modification is replayed.
To fix this, we need to ensure that we do not set the inode buffer
flag in the buffer log item format flags if the inode allocation has
not already hit the log. To avoid requiring a change to log
recovery, we really need to make this a modification that relies
only on in-memory sate.
We can do this by checking during buffer log formatting (while the
CIL cannot be flushed) if we are still in the same sequence when we
commit the unlink transaction as the inode allocation transaction.
If we are, then we do not add the inode buffer flag to the buffer
log format item flags. This means the entire buffer will be
replayed, not just the unlinked fields. We do this while
CIL flusheѕ are locked out to ensure that we don't race with the
sequence numbers changing and hence fail to put the inode buffer
flag in the buffer format flags when we really need to.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
If we let the CIL grow without bound, it will grow large enough to violate
recovery constraints (must be at least one complete transaction in the log at
all times) or take forever to write out through the log buffers. Hence we need
a check during asynchronous transactions as to whether the CIL needs to be
pushed.
We track the amount of log space the CIL consumes, so it is relatively simple
to limit it on a pure size basis. Make the limit the minimum of just under half
the log size (recovery constraint) or 8MB of log space (which is an awful lot
of metadata).
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
If the filesystem is being shut down and the there is no log error,
the current code forces out the current log buffers. This code now needs
to push the CIL before it forces out the log buffers to acheive the same
result.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The delayed logging code only changes in-memory structures and as
such can be enabled and disabled with a mount option. Add the mount
option and emit a warning that this is an experimental feature that
should not be used in production yet.
We also need infrastructure to track committed items that have not
yet been written to the log. This is what the Committed Item List
(CIL) is for.
The log item also needs to be extended to track the current log
vector, the associated memory buffer and it's location in the Commit
Item List. Extend the log item and log vector structures to enable
this tracking.
To maintain the current log format for transactions with delayed
logging, we need to introduce a checkpoint transaction and a context
for tracking each checkpoint from initiation to transaction
completion. This includes adding a log ticket for tracking space
log required/used by the context checkpoint.
To track all the changes we need an io vector array per log item,
rather than a single array for the entire transaction. Using the new
log vector structure for this requires two passes - the first to
allocate the log vector structures and chain them together, and the
second to fill them out. This log vector chain can then be passed
to the CIL for formatting, pinning and insertion into the CIL.
Formatting of the log vector chain is relatively simple - it's just
a loop over the iovecs on each log vector, but it is made slightly
more complex because we re-write the iovec after the copy to point
back at the memory buffer we just copied into.
This code also needs to pin log items. If the log item is not
already tracked in this checkpoint context, then it needs to be
pinned. Otherwise it is already pinned and we don't need to pin it
again.
The only other complexity is calculating the amount of new log space
the formatting has consumed. This needs to be accounted to the
transaction in progress, and the accounting is made more complex
becase we need also to steal space from it for log metadata in the
checkpoint transaction. Calculate all this at insert time and update
all the tickets, counters, etc correctly.
Once we've formatted all the log items in the transaction, attach
the busy extents to the checkpoint context so the busy extents live
until checkpoint completion and can be processed at that point in
time. Transactions can then be freed at this point in time.
Now we need to issue checkpoints - we are tracking the amount of log space
used by the items in the CIL, so we can trigger background checkpoints when the
space usage gets to a certain threshold. Otherwise, checkpoints need ot be
triggered when a log synchronisation point is reached - a log force event.
Because the log write code already handles chained log vectors, writing the
transaction is trivial, too. Construct a transaction header, add it
to the head of the chain and write it into the log, then issue a
commit record write. Then we can release the checkpoint log ticket
and attach the context to the log buffer so it can be called during
Io completion to complete the checkpoint.
We also need to allow for synchronising multiple in-flight
checkpoints. This is needed for two things - the first is to ensure
that checkpoint commit records appear in the log in the correct
sequence order (so they are replayed in the correct order). The
second is so that xfs_log_force_lsn() operates correctly and only
flushes and/or waits for the specific sequence it was provided with.
To do this we need a wait variable and a list tracking the
checkpoint commits in progress. We can walk this list and wait for
the checkpoints to change state or complete easily, an this provides
the necessary synchronisation for correct operation in both cases.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
When we free a metadata extent, we record it in the per-AG busy
extent array so that it is not re-used before the freeing
transaction hits the disk. This array is fixed size, so when it
overflows we make further allocation transactions synchronous
because we cannot track more freed extents until those transactions
hit the disk and are completed. Under heavy mixed allocation and
freeing workloads with large log buffers, we can overflow this array
quite easily.
Further, the array is sparsely populated, which means that inserts
need to search for a free slot, and array searches often have to
search many more slots that are actually used to check all the
busy extents. Quite inefficient, really.
To enable this aspect of extent freeing to scale better, we need
a structure that can grow dynamically. While in other areas of
XFS we have used radix trees, the extents being freed are at random
locations on disk so are better suited to being indexed by an rbtree.
So, use a per-AG rbtree indexed by block number to track busy
extents. This incures a memory allocation when marking an extent
busy, but should not occur too often in low memory situations. This
should scale to an arbitrary number of extents so should not be a
limitation for features such as in-memory aggregation of
transactions.
However, there are still situations where we can't avoid allocating
busy extents (such as allocation from the AGFL). To minimise the
overhead of such occurences, we need to avoid doing a synchronous
log force while holding the AGF locked to ensure that the previous
transactions are safely on disk before we use the extent. We can do
this by marking the transaction doing the allocation as synchronous
rather issuing a log force.
Because of the locking involved and the ordering of transactions,
the synchronous transaction provides the same guarantees as a
synchronous log force because it ensures that all the prior
transactions are already on disk when the synchronous transaction
hits the disk. i.e. it preserves the free->allocate order of the
extent correctly in recovery.
By doing this, we avoid holding the AGF locked while log writes are
in progress, hence reducing the length of time the lock is held and
therefore we increase the rate at which we can allocate and free
from the allocation group, thereby increasing overall throughput.
The only problem with this approach is that when a metadata buffer is
marked stale (e.g. a directory block is removed), then buffer remains
pinned and locked until the log goes to disk. The issue here is that
if that stale buffer is reallocated in a subsequent transaction, the
attempt to lock that buffer in the transaction will hang waiting
the log to go to disk to unlock and unpin the buffer. Hence if
someone tries to lock a pinned, stale, locked buffer we need to
push on the log to get it unlocked ASAP. Effectively we are trading
off a guaranteed log force for a much less common trigger for log
force to occur.
Ideally we should not reallocate busy extents. That is a much more
complex fix to the problem as it involves direct intervention in the
allocation btree searches in many places. This is left to a future
set of modifications.
Finally, now that we track busy extents in allocated memory, we
don't need the descriptors in the transaction structure to point to
them. We can replace the complex busy chunk infrastructure with a
simple linked list of busy extents. This allows us to remove a large
chunk of code, making the overall change a net reduction in code
size.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The ticket ID is needed to uniquely identify transactions when doing busy
extent matching. Delayed logging changes the lifecycle of busy extents with
respect to the transaction structure lifecycle. Hence we can no longer use
the transaction structure as a means of determining the owner of the busy
extent as it may be freed and reused while the busy extent is still active.
This commit provides the infrastructure to access the xlog_tid_t held in the
ticket from a transaction handle. This avoids the need for callers to peek
into the transaction and log structures to find this out.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Push the error message output when a ticket overrun is detected
into the ticket printing functions. Also remove the debug version
of the code as the production version will still panic just as
effectively on a debug kernel via the panic mask being set.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Clean up the buffer log format (XFS_BLI_*) flags because they have a
polluted namespace. They XFS_BLI_ prefix is used for both in-memory
and on-disk flag feilds, but have overlapping values for different
flags. Rename the buffer log format flags to use the XFS_BLF_*
prefix to avoid confusing them with the in-memory XFS_BLI_* prefixed
flags.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The buffer log item reference counts used to take referenceѕ for every
transaction, similar to the pin counting. This is symmetric (like the
pin/unpin) with respect to transaction completion, but with dleayed logging
becomes assymetric as the pinning becomes assymetric w.r.t. transaction
completion.
To make both cases the same, allow the buffer pinning to take a reference to
the buffer log item and always drop the reference the transaction has on it
when being unlocked. This is balanced correctly because the unpin operation
always drops a reference to the log item. Hence reference counting becomes
symmetric w.r.t. item pinning as well as w.r.t active transactions and as a
result the reference counting model remain consistent between normal and
delayed logging.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Delayed logging currently requires ticket allocation to succeed, so
we need to be able to sleep on allocation. It also should not allow
memory allocation to recurse into the filesystem. hence we need to
pass allocation flags directing the type of allocation the caller
requires.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The transaction ID is written into the log as the unique identifier
for transactions during recover. When duplicating a transaction, we
reuse the log ticket, which means it has the same transaction ID as
the previous transaction.
Rather than regenerating a random transaction ID for the duplicated
transaction, just add one to the current ID so that duplicated
transaction can be easily spotted in the log and during recovery
during problem diagnosis.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (69 commits)
fix handling of offsets in cris eeprom.c, get rid of fake on-stack files
get rid of home-grown mutex in cris eeprom.c
switch ecryptfs_write() to struct inode *, kill on-stack fake files
switch ecryptfs_get_locked_page() to struct inode *
simplify access to ecryptfs inodes in ->readpage() and friends
AFS: Don't put struct file on the stack
Ban ecryptfs over ecryptfs
logfs: replace inode uid,gid,mode initialization with helper function
ufs: replace inode uid,gid,mode initialization with helper function
udf: replace inode uid,gid,mode init with helper
ubifs: replace inode uid,gid,mode initialization with helper function
sysv: replace inode uid,gid,mode initialization with helper function
reiserfs: replace inode uid,gid,mode initialization with helper function
ramfs: replace inode uid,gid,mode initialization with helper function
omfs: replace inode uid,gid,mode initialization with helper function
bfs: replace inode uid,gid,mode initialization with helper function
ocfs2: replace inode uid,gid,mode initialization with helper function
nilfs2: replace inode uid,gid,mode initialization with helper function
minix: replace inode uid,gid,mode init with helper
ext4: replace inode uid,gid,mode init with helper
...
Trivial conflict in fs/fs-writeback.c (mark bitfields unsigned)
Pass the larger struct fs_disk_quota to the ->set_dqblk operation so
that the Q_SETQUOTA and Q_XSETQUOTA operations can be implemented
with a single filesystem operation and we can retire the ->set_xquota
operation. The additional information (RT-subvolume accounting and
warn counts) are left zero for the VFS quota implementation.
Add new fieldmask values for setting the numer of blocks and inodes
values which is required for the VFS quota, but wasn't for XFS.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Pass the larger struct fs_disk_quota to the ->get_dqblk operation so
that the Q_GETQUOTA and Q_XGETQUOTA operations can be implemented
with a single filesystem operation and we can retire the ->get_xquota
operation. The additional information (RT-subvolume accounting and
warn counts) are left zero for the VFS quota implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Rename all iomap_valid identifiers to imap_valid to fit the new
world order, and clean up xfs_iomap_valid to convert the passed in
offset to blocks instead of the imap values to bytes. Use the
simpler inode->i_blkbits instead of the XFS macros for this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The IOMAP_ flags are now only used inside xfs_aops.c for extent
probing and I/O completion tracking, so more them here, and rename
them to IO_* as there's no mapping involved at all.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Now that struct xfs_iomap contains exactly the same units as struct
xfs_bmbt_irec we can just use the latter directly in the aops code.
Replace the missing IOMAP_NEW flag with a new boolean output
parameter to xfs_iomap.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Report the iomap_bn field of struct xfs_iomap in terms of filesystem
blocks instead of in terms of bytes. Shift the byte conversions
into the caller, and replace the IOMAP_DELAY and IOMAP_HOLE flag
checks with checks for HOLESTARTBLOCK and DELAYSTARTBLOCK.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
Report the iomap_offset and iomap_bsize fields of struct xfs_iomap
in terms of fsblocks instead of in terms of disk blocks. Shift the
byte conversions into the callers temporarily, but they will
disappear or get cleaned up later.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
The iomap_delta field in struct xfs_iomap just contains the
difference between the offset passed to xfs_iomap and the
iomap_offset. Just calculate it in the only caller that cares.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Alex Elder <aelder@sgi.com>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
> +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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
* '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
...
* '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
...
* '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
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
* '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
...
* 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
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Christoph Hellwig