Both the data and attr fork have a format that is stored in the legacy
idinode. Move it into the xfs_ifork structure instead, where it uses
up padding.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
There are there are three extents counters per inode, one for each of
the forks. Two are in the legacy icdinode and one is directly in
struct xfs_inode. Switch to a single counter in the xfs_ifork structure
where it uses up padding at the end of the structure. This simplifies
various bits of code that just wants the number of extents counter and
can now directly dereference it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
In certain situations the background CIL push can be indefinitely
delayed. While we have workarounds from the obvious cases now, it
doesn't solve the underlying issue. This issue is that there is no
upper limit on the CIL where we will either force or wait for
a background push to start, hence allowing the CIL to grow without
bound until it consumes all log space.
To fix this, add a new wait queue to the CIL which allows background
pushes to wait for the CIL context to be switched out. This happens
when the push starts, so it will allow us to block incoming
transaction commit completion until the push has started. This will
only affect processes that are running modifications, and only when
the CIL threshold has been significantly overrun.
This has no apparent impact on performance, and doesn't even trigger
until over 45 million inodes had been created in a 16-way fsmark
test on a 2GB log. That was limiting at 64MB of log space used, so
the active CIL size is only about 3% of the total log in that case.
The concurrent removal of those files did not trigger the background
sleep at all.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Remove xlog_ticket_done and just call the renamed low-level helpers for
ungranting or regranting log space directly. To make that a little
the reference put on the ticket and all tracing is moved into the actual
helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Add a new btree function that enables us to bulk load a btree cursor.
This will be used by the upcoming online repair patches to generate new
btrees. This avoids the programmatic inefficiency of calling
xfs_btree_insert in a loop (which generates a lot of log traffic) in
favor of stamping out new btree blocks with ordered buffers, and then
committing both the new root and scheduling the removal of the old btree
blocks in a single transaction commit.
The design of this new generic code is based off the btree rebuilding
code in xfs_repair's phase 5 code, with the explicit goal of enabling us
to share that code between scrub and repair. It has the additional
feature of being able to control btree block loading factors.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create an in-core fake root for inode-rooted btree types so that callers
can generate a whole new btree using the upcoming btree bulk load
function without making the new tree accessible from the rest of the
filesystem. It is up to the individual btree type to provide a function
to create a staged cursor (presumably with the appropriate callouts to
update the fakeroot) and then commit the staged root back into the
filesystem.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create an in-core fake root for AG-rooted btree types so that callers
can generate a whole new btree using the upcoming btree bulk load
function without making the new tree accessible from the rest of the
filesystem. It is up to the individual btree type to provide a function
to create a staged cursor (presumably with the appropriate callouts to
update the fakeroot) and then commit the staged root back into the
filesystem.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The attrlist cursor only exists as part of an attr list context, so
embedd the structure instead of pointing to it. Also give it a proper
xfs_ prefix and remove the obsolete typedef.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Now that we use the on-disk flags field also for the interface to the
lower level attr routines we can use the XFS_ATTR_INCOMPLETE definition
from the on-disk format directly instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The ATTR_* flags have a long IRIX history, where they a userspace
interface, the on-disk format and an internal interface. We've split
out the on-disk interface to the XFS_ATTR_* values, but despite (or
because?) of that the flag have still been a mess. Switch the
internal interface to pass the on-disk XFS_ATTR_* flags for the
namespace and the Linux XATTR_* flags for the actual flags instead.
The ATTR_* values that are actually used are move to xfs_fs.h with a
new XFS_IOC_* prefix to not conflict with the userspace version that
has the same name and must have the same value.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Replace the alist char pointer with a void buffer given that different
callers use it in different ways. Use the chance to remove the typedef
and reduce the indentation of the struct definition so that it doesn't
overflow 80 char lines all over.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Rajendra <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Alex Lyakas reported[1] that mounting an xfs filesystem with new sunit
and swidth values could cause xfs_repair to fail loudly. The problem
here is that repair calculates the where mkfs should have allocated the
root inode, based on the superblock geometry. The allocation decisions
depend on sunit, which means that we really can't go updating sunit if
it would lead to a subsequent repair failure on an otherwise correct
filesystem.
Port from xfs_repair some code that computes the location of the root
inode and teach mount to skip the ondisk update if it would cause
problems for repair. Along the way we'll update the documentation,
provide a function for computing the minimum AGFL size instead of
open-coding it, and cut down some indenting in the mount code.
Note that we allow the mount to proceed (and new allocations will
reflect this new geometry) because we've never screened this kind of
thing before. We'll have to wait for a new future incompat feature to
enforce correct behavior, alas.
Note that the geometry reporting always uses the superblock values, not
the incore ones, so that is what xfs_info and xfs_growfs will report.
[1] https://lore.kernel.org/linux-xfs/20191125130744.GA44777@bfoster/T/#m00f9594b511e076e2fcdd489d78bc30216d72a7d
Reported-by: Alex Lyakas <alex@zadara.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Rework event_create_dir() to use an array of static data instead of
function pointers where possible.
The problem is that it would call the function pointer on module load
before parse_args(), possibly even before jump_labels were initialized.
Luckily the generated functions don't use jump_labels but it still seems
fragile. It also gets in the way of changing when we make the module map
executable.
The generated function are basically calling trace_define_field() with a
bunch of static arguments. So instead of a function, capture these
arguments in a static array, avoiding the function call.
Now there are a number of cases where the fields are dynamic (syscall
arguments, kprobes and uprobes), in which case a static array does not
work, for these we preserve the function call. Luckily all these cases
are not related to modules and so we can retain the function call for
them.
Also fix up all broken tracepoint definitions that now generate a
compile error.
Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Use the allocsize name to match the mount option and usage instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The near mode fallback algorithm consists of a left/right scan of
the bnobt. This algorithm has very poor breakdown characteristics
under worst case free space fragmentation conditions. If a suitable
extent is far enough from the locality hint, each allocation may
scan most or all of the bnobt before it completes. This causes
pathological behavior and extremely high allocation latencies.
While locality is important to near mode allocations, it is not so
important as to incur pathological allocation latency to provide the
asolute best available locality for every allocation. If the
allocation is large enough or far enough away, there is a point of
diminishing returns. As such, we can bound the overall operation by
including an iterative cntbt lookup in the broader search. The cntbt
lookup is optimized to immediately find the extent with best
locality for the given size on each iteration. Since the cntbt is
indexed by extent size, the lookup repeats with a variably
aggressive increasing search key size until it runs off the edge of
the tree.
This approach provides a natural balance between the two algorithms
for various situations. For example, the bnobt scan is able to
satisfy smaller allocations such as for inode chunks or btree blocks
more quickly where the cntbt search may have to search through a
large set of extent sizes when the search key starts off small
relative to the largest extent in the tree. On the other hand, the
cntbt search more deterministically covers the set of suitable
extents for larger data extent allocation requests that the bnobt
scan may have to search the entire tree to locate.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Lift the btree fixup path into a helper function.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The near mode bnobt scan searches left and right in the bnobt
looking for the closest free extent to the allocation hint that
satisfies minlen. Once such an extent is found, the left/right
search terminates, we search one more time in the opposite direction
and finish the allocation with the best overall extent.
The left/right and find best searches are currently controlled via a
combination of cursor state and local variables. Clean up this code
and prepare for further improvements to the near mode fallback
algorithm by reusing the allocation cursor best extent tracking
mechanism. Update the tracking logic to deactivate bnobt cursors
when out of allocation range and replace open-coded extent checks to
calls to the common helper. In doing so, rename some misnamed local
variables in the top-level near mode allocation function.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The cntbt lastblock scan checks the size, alignment, locality, etc.
of each free extent in the block and compares it with the current
best candidate. This logic will be reused by the upcoming optimized
cntbt algorithm, so refactor it into a separate helper. Note that
acur->diff is now initialized to -1 (unsigned) instead of 0 to
support the more granular comparison logic in the new helper.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Take the xfs writeback code and move it to fs/iomap. A new structure
with three methods is added as the abstraction from the generic writeback
code to the file system. These methods are used to map blocks, submit an
ioend, and cancel a page that encountered an error before it was added to
an ioend.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[darrick: rename ->submit_ioend to ->prepare_ioend to clarify what it
does]
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Lift the xfs code for tracing address space operations to the iomap
layer.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Memory we use to submit for IO needs strict alignment to the
underlying driver contraints. Worst case, this is 512 bytes. Given
that all allocations for IO are always a power of 2 multiple of 512
bytes, the kernel heap provides natural alignment for objects of
these sizes and that suffices.
Until, of course, memory debugging of some kind is turned on (e.g.
red zones, poisoning, KASAN) and then the alignment of the heap
objects is thrown out the window. Then we get weird IO errors and
data corruption problems because drivers don't validate alignment
and do the wrong thing when passed unaligned memory buffers in bios.
TO fix this, introduce kmem_alloc_io(), which will guaranteeat least
512 byte alignment of buffers for IO, even if memory debugging
options are turned on. It is assumed that the minimum allocation
size will be 512 bytes, and that sizes will be power of 2 mulitples
of 512 bytes.
Use this everywhere we allocate buffers for IO.
This no longer fails with log recovery errors when KASAN is enabled
due to the brd driver not handling unaligned memory buffers:
# mkfs.xfs -f /dev/ram0 ; mount /dev/ram0 /mnt/test
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
When trying to correlate XFS kernel allocations to memory reclaim
behaviour, it is useful to know what allocations XFS is actually
attempting. This information is not directly available from
tracepoints in the generic memory allocation and reclaim
tracepoints, so these new trace points provide a high level
indication of what the XFS memory demand actually is.
There is no per-filesystem context in this code, so we just trace
the type of allocation, the size and the allocation constraints.
The kmem code also doesn't include much of the common XFS headers,
so there are a few definitions that need to be added to the trace
headers and a couple of types that need to be made common to avoid
needing to include the whole world in the kmem code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Create a parallel iwalk implementation and switch quotacheck to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Create a new iterator function to simplify walking inodes in an XFS
filesystem. This new iterator will replace the existing open-coded
walking that goes on in various places.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
The iop_unlock method is called when comitting or cancelling a
transaction. In the latter case, the transaction may or may not be
aborted. While there is no known problem with the current code in
practice, this implementation is limited in that any log item
implementation that might want to differentiate between a commit and a
cancellation must rely on the aborted state. The aborted bit is only
set when the cancelled transaction is dirty, however. This means that
there is no way to distinguish between a commit and a clean transaction
cancellation.
For example, intent log items currently rely on this distinction. The
log item is either transferred to the CIL on commit or released on
transaction cancel. There is currently no possibility for a clean intent
log item in a transaction, but if that state is ever introduced a cancel
of such a transaction will immediately result in memory leaks of the
associated log item(s). This is an interface deficiency and landmine.
To clean this up, replace the iop_unlock method with an iop_release
method that is specific to transaction cancel. The existing
iop_committing method occurs at the same time as iop_unlock in the
commit path and there is no need for two separate callbacks here.
Overload the iop_committing method with the current commit time
iop_unlock implementations to eliminate the need for the latter and
further simplify the interface.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
While commiting items looks very similar to freeing them on error it is
a different operation, and they will diverge a bit soon.
Split out the commit case from xfs_trans_free_items, inline it into
xfs_log_commit_cil and give it a separate trace point.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
If we know the filesystem metadata isn't healthy during unmount, we want
to encourage the administrator to run xfs_repair right away. We can't
do this if BAD_SUMMARY will cause an unclean log unmount to force
summary recalculation, so turn it off if the fs is bad.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Add the necessary in-core metadata fields to keep track of which parts
of the filesystem have been observed and which parts were observed to be
unhealthy, and print a warning at unmount time if we have unfixed
problems.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Besides simplifying the code a bit this allows to actually implement
the behavior of using COW preallocation for non-COW data mentioned
in the current comments.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The io_type field contains what is basically a summary of information
from the inode fork and the imap. But we can just as easily use that
information directly, simplifying a few bits here and there and
improving the trace points.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Use a rhashtable to cache the unlinked list incore. This should speed
up unlinked processing considerably when there are a lot of inodes on
the unlinked list because iunlink_remove no longer has to traverse an
entire bucket list to find which inode points to the one being removed.
The incore list structure records "X.next_unlinked = Y" relations, with
the rhashtable using Y to index the records. This makes finding the
inode X that points to a inode Y very quick. If our cache fails to find
anything we can always fall back on the old method.
FWIW this drastically reduces the amount of time it takes to remove
inodes from the unlinked list. I wrote a program to open a lot of
O_TMPFILE files and then close them in the same order, which takes
a very long time if we have to traverse the unlinked lists. With the
ptach, I see:
+ /d/t/tmpfile/tmpfile
Opened 193531 files in 6.33s.
Closed 193531 files in 5.86s
real 0m12.192s
user 0m0.064s
sys 0m11.619s
+ cd /
+ umount /mnt
real 0m0.050s
user 0m0.004s
sys 0m0.030s
And without the patch:
+ /d/t/tmpfile/tmpfile
Opened 193588 files in 6.35s.
Closed 193588 files in 751.61s
real 12m38.853s
user 0m0.084s
sys 12m34.470s
+ cd /
+ umount /mnt
real 0m0.086s
user 0m0.000s
sys 0m0.060s
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Add tracepoints so we can associate high level operations with low level
updates. No functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Hoist the functions that update an inode's unlinked pointer updates into
a helper. No functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Split the AGI unlinked bucket updates into a separate function. No
functional changes.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Use __print_symbolic to print the btree type in ftrace output.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Move XFS_INODE_FORMAT_STR to libxfs so that we don't forget to keep it
updated, and add necessary TRACE_DEFINE_ENUM.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Move XFS_AG_BTREE_CMP_FORMAT_STR to libxfs so that we don't forget to
keep it updated, and TRACE_DEFINE_ENUM the values while we're at it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
ftrace's __print_symbolic() has a (very poorly documented) requirement
that any enum values used in the symbol to string translation table be
wrapped in a TRACE_DEFINE_ENUM so that the enum value can be encoded in
the ftrace ring buffer. Fix this unsatisfied requirement.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Only certain functions actually change the contents of an
xfs_owner_info; the rest can accept a const struct pointer. This will
enable us to save stack space by hoisting static owner info types to
be const global variables.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
There's no need to bundle a pointer to the defer op type into the defer
op control structure. Instead, store the defer op type enum, which
enables us to shorten some of the lines.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
xfstests generic/388,475 occasionally reproduce assertion failures
in xfs_buf_item_unpin() when the final bli reference is dropped on
an invalidated buffer and the buffer is not locked as it is expected
to be. Invalidated buffers should remain locked on transaction
commit until the final unpin, at which point the buffer is removed
from the AIL and the bli is freed since stale buffers are not
written back.
The assert failures are associated with filesystem shutdown,
typically due to log I/O errors injected by the test. The
problematic situation can occur if the shutdown happens to cause a
race between an active transaction that has invalidated a particular
buffer and an I/O error on a log buffer that contains the bli
associated with the same (now stale) buffer.
Both transaction and log contexts acquire a bli reference. If the
transaction has already invalidated the buffer by the time the I/O
error occurs and ends up aborting due to shutdown, the transaction
and log hold the last two references to a stale bli. If the
transaction cancel occurs first, it treats the buffer as non-stale
due to the aborted state: the bli reference is dropped and the
buffer is released/unlocked. The log buffer I/O error handling
eventually calls into xfs_buf_item_unpin(), drops the final
reference to the bli and treats it as stale. The buffer wasn't left
locked by xfs_buf_item_unlock(), however, so the assert fails and
the buffer is double unlocked. The latter problem is mitigated by
the fact that the fs is shutdown and no further damage is possible.
->iop_unlock() of an invalidated buffer should behave consistently
with respect to the bli refcount, regardless of aborted state. If
the refcount remains elevated on commit, we know the bli is awaiting
an unpin (since it can't be in another transaction) and will be
handled appropriately on log buffer completion. If the final bli
reference of an invalidated buffer is dropped in ->iop_unlock(), we
can assume the transaction has aborted because invalidation implies
a dirty transaction. In the non-abort case, the log would have
acquired a bli reference in ->iop_pin() and prevented bli release at
->iop_unlock() time. In the abort case the item must be freed and
buffer unlocked because it wasn't pinned by the log.
Rework xfs_buf_item_unlock() to simplify the currently circuitous
and duplicate logic and leave invalidated buffers locked based on
bli refcount, regardless of aborted state. This ensures that a
pinned, stale buffer is always found locked when eventually
unpinned.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
struct xfs_defer_ops has now been reduced to a single list_head. The
external dfops mechanism is unused and thus everywhere a (permanent)
transaction is accessible the associated dfops structure is as well.
Remove the xfs_defer_ops structure and fold the list_head into the
transaction. Also remove the last remnant of external dfops in
xfs_trans_dup().
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The xfs_defer_ops ->dop_pending list is used to track active
deferred operations once intents are logged. These items must be
aborted in the event of an error. The list is populated as intents
are logged and items are removed as they complete (or are aborted).
Now that xfs_defer_finish() cancels on error, there is no need to
ever access ->dop_pending outside of xfs_defer_finish(). The list is
only ever populated after xfs_defer_finish() begins and is either
completed or cancelled before it returns.
Remove ->dop_pending from xfs_defer_ops and replace it with a local
list in the xfs_defer_finish() path. Pass the local list to the
various helpers now that it is not accessible via dfops. Note that
we have to check for NULL in the abort case as the final tx roll
occurs outside of the scope of the new local list (once the dfops
has completed and thus drained the list).
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The dop_low field enables the low free space allocation mode when a
previous allocation has detected difficulty allocating blocks. It
has historically been part of the xfs_defer_ops structure, which
means if enabled, it remains enabled across a set of transactions
until the deferred operations have completed and the dfops is reset.
Now that the dfops is embedded in the transaction, we can save a bit
more space by using a transaction flag rather than a standalone
boolean. Drop the ->dop_low field and replace it with a transaction
flag that is set at the same points, carried across rolling
transactions and cleared on completion of deferred operations. This
essentially emulates the behavior of ->dop_low and so should not
change behavior.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
dop_committed is set when deferred item processing rolls the
transaction at least once, but is only ever accessed in tracepoints.
The transaction roll/commit events are already available via
independent tracepoints, so remove the otherwise unused field.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Sync and async buffer submission both do generally similar things
with a couple odd exceptions. Refactor the core buffer submission
code into a common helper to isolate buffer submission from
completion handling of synchronous buffer I/O.
This patch does not change behavior. It is a step towards support
for using synchronous buffer I/O via synchronous delwri queue
submission.
Designed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The xfs_alloc_arg.firstblock field is used to control the starting
agno for an allocation. The structure already carries a pointer to
the transaction, which carries the current firstblock value.
Remove the field and access ->t_firstblock directly in the
allocation code.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
