Log recovery has particular rules around buffer submission along with
tricky corner cases where independent transactions can share an LSN. As
such, it can be difficult to follow when/why buffers are submitted
during recovery.
Add a couple tracepoints to post the current LSN of a record when a new
record is being processed and when a buffer is being skipped due to LSN
ordering. Also, update the recover item class to include the LSN of the
current transaction for the item being processed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Log recovery is currently broken for v5 superblocks in that it never
updates the metadata LSN of buffers written out during recovery. The
metadata LSN is recorded in various bits of metadata to provide recovery
ordering criteria that prevents transient corruption states reported by
buffer write verifiers. Without such ordering logic, buffer updates can
be replayed out of order and lead to false positive transient corruption
states. This is generally not a corruption vector on its own, but
corruption detection shuts down the filesystem and ultimately prevents a
mount if it occurs during log recovery. This requires an xfs_repair run
that clears the log and potentially loses filesystem updates.
This problem is avoided in most cases as metadata writes during normal
filesystem operation update the metadata LSN appropriately. The problem
with log recovery not updating metadata LSNs manifests if the system
happens to crash shortly after log recovery itself. In this scenario, it
is possible for log recovery to complete all metadata I/O such that the
filesystem is consistent. If a crash occurs after that point but before
the log tail is pushed forward by subsequent operations, however, the
next mount performs the same log recovery over again. If a buffer is
updated multiple times in the dirty range of the log, an earlier update
in the log might not be valid based on the current state of the
associated buffer after all of the updates in the log had been replayed
(before the previous crash). If a verifier happens to detect such a
problem, the filesystem claims corruption and immediately shuts down.
This commonly manifests in practice as directory block verifier failures
such as the following, likely due to directory verifiers being
particularly detailed in their checks as compared to most others:
...
Mounting V5 Filesystem
XFS (dm-0): Starting recovery (logdev: internal)
XFS (dm-0): Internal error XFS_WANT_CORRUPTED_RETURN at line ... of \
file fs/xfs/libxfs/xfs_dir2_data.c. Caller xfs_dir3_data_verify ...
...
Update log recovery to update the metadata LSN of recovered buffers.
Since metadata LSNs are already updated by write verifer functions via
attached log items, attach a dummy log item to the buffer during
validation and explicitly set the LSN of the current transaction. This
ensures that the metadata LSN of a buffer is updated based on whether
the recovery I/O actually completes, and if so, that subsequent recovery
attempts identify that the buffer is already up to date with respect to
the current transaction.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The log recovery buffer validation function is invoked in cases where a
buffer update may be skipped due to LSN ordering. If the validation
function happens to come across directory conversion situations (e.g., a
dir3 block to data conversion), it may warn about seeing a buffer log
format of one type and a buffer with a magic number of another.
This warning is not valid as the buffer update is ultimately skipped.
This is indicated by a current_lsn of NULLCOMMITLSN provided by the
caller. As such, update xlog_recover_validate_buf_type() to only warn in
such cases when a buffer update is expected.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The current LSN must be available to the buffer validation function to
provide the ability to update the metadata LSN of the buffer. Pass the
current_lsn value down to xlog_recover_validate_buf_type() in
preparation.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The fix to log recovery to update the metadata LSN in recovered buffers
introduces the requirement that a buffer is submitted only once per
current LSN. Log recovery currently submits buffers on transaction
boundaries. This is not sufficient as the abstraction between log
records and transactions allows for various scenarios where multiple
transactions can share the same current LSN. If independent transactions
share an LSN and both modify the same buffer, log recovery can
incorrectly skip updates and leave the filesystem in an inconsisent
state.
In preparation for proper metadata LSN updates during log recovery,
update log recovery to submit buffers for write on LSN change boundaries
rather than transaction boundaries. Explicitly track the current LSN in
a new struct xlog field to handle the various corner cases of when the
current LSN may or may not change.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Recently we've had a number of reports where log recovery on a v5
filesystem has reported corruptions that looked to be caused by
recovery being re-run over the top of an already-recovered
metadata. This has uncovered a bug in recovery (fixed elsewhere)
but the vector that caused this was largely unknown.
A kdump test started tripping over this problem - the system
would be crashed, the kdump kernel and environment would boot and
dump the kernel core image, and then the system would reboot. After
reboot, the root filesystem was triggering log recovery and
corruptions were being detected. The metadumps indicated the above
log recovery issue.
What is happening is that the kdump kernel and environment is
mounting the root device read-only to find the binaries needed to do
it's work. The result of this is that it is running log recovery.
However, because there were unlinked files and EFIs to be processed
by recovery, the completion of phase 1 of log recovery could not
mark the log clean. And because it's a read-only mount, the unmount
process does not write records to the log to mark it clean, either.
Hence on the next mount of the filesystem, log recovery was run
again across all the metadata that had already been recovered and
this is what triggered corruption warnings.
To avoid this problem, we need to ensure that a read-only mount
always updates the log when it completes the second phase of
recovery. We already handle this sort of issue with rw->ro remount
transitions, so the solution is as simple as quiescing the
filesystem at the appropriate time during the mount process. This
results in the log being marked clean so the mount behaviour
recorded in the logs on repeated RO mounts will change (i.e. log
recovery will no longer be run on every mount until a RW mount is
done). This is a user visible change in behaviour, but it is
harmless.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When adding a new remote attribute, we write the attribute to the
new extent before the allocation transaction is committed. This
means we cannot reuse busy extents as that violates crash
consistency semantics. Hence we currently treat remote attribute
extent allocation like userdata because it has the same overwrite
ordering constraints as userdata.
Unfortunately, this also allows the allocator to incorrectly apply
extent size hints to the remote attribute extent allocation. This
results in interesting failures, such as transaction block
reservation overruns and in-memory inode attribute fork corruption.
To fix this, we need to separate the busy extent reuse configuration
from the userdata configuration. This changes the definition of
XFS_BMAPI_METADATA slightly - it now means that allocation is
metadata and reuse of busy extents is acceptible due to the metadata
ordering semantics of the journal. If this flag is not set, it
means the allocation is that has unordered data writeback, and hence
busy extent reuse is not allowed. It no longer implies the
allocation is for user data, just that the data write will not be
strictly ordered. This matches the semantics for both user data
and remote attribute block allocation.
As such, This patch changes the "userdata" field to a "datatype"
field, and adds a "no busy reuse" flag to the field.
When we detect an unordered data extent allocation, we immediately set
the no reuse flag. We then set the "user data" flags based on the
inode fork we are allocating the extent to. Hence we only set
userdata flags on data fork allocations now and consider attribute
fork remote extents to be an unordered metadata extent.
The result is that remote attribute extents now have the expected
allocation semantics, and the data fork allocation behaviour is
completely unchanged.
It should be noted that there may be other ways to fix this (e.g.
use ordered metadata buffers for the remote attribute extent data
write) but they are more invasive and difficult to validate both
from a design and implementation POV. Hence this patch takes the
simple, obvious route to fixing the problem...
Reported-and-tested-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
inode_change_ok() will be resposible for clearing capabilities and IMA
extended attributes and as such will need dentry. Give it as an argument
to inode_change_ok() instead of an inode. Also rename inode_change_ok()
to setattr_prepare() to better relect that it does also some
modifications in addition to checks.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
To avoid clearing of capabilities or security related extended
attributes too early, inode_change_ok() will need to take dentry instead
of inode. Propagate dentry down to functions calling inode_change_ok().
This is rather straightforward except for xfs_set_mode() function which
does not have dentry easily available. Luckily that function does not
call inode_change_ok() anyway so we just have to do a little dance with
function prototypes.
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
When file permissions are modified via chmod(2) and the user is not in
the owning group or capable of CAP_FSETID, the setgid bit is cleared in
inode_change_ok(). Setting a POSIX ACL via setxattr(2) sets the file
permissions as well as the new ACL, but doesn't clear the setgid bit in
a similar way; this allows to bypass the check in chmod(2). Fix that.
References: CVE-2016-7097
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Another users of buffer_heads bytes the dust.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Rename the current function to __xfs_setfilesize and add a non-static
wrapper that also takes care of creating the transaction. This new
helper will be used by the new iomap-based DAX path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We always just read the extent first, and will later lock exlusively
after first dropping the lock in case we actually allocate blocks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
So far DAX writes inherited the locking from direct I/O writes, but
the direct I/O model of using shared locks for writes is actually
wrong for DAX. For direct I/O we're out of any standards and don't
have to provide the Posix required exclusion between writers, but
for DAX which gets transparently enable on applications without any
knowledge of it we can't simply drop the requirement. Even worse
this only happens for aligned writes and thus doesn't show up for
many typical use cases.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently xfs_iomap_write_delay does up to lookups in the inode
extent tree, which is rather costly especially with the new iomap
based write path and small write sizes.
But it turns out that the low-level xfs_bmap_search_extents gives us
all the information we need in the regular delalloc buffered write
path:
- it will return us an extent covering the block we are looking up
if it exists. In that case we can simply return that extent to
the caller and are done
- it will tell us if we are beyoned the last current allocated
block with an eof return parameter. In that case we can create a
delalloc reservation and use the also returned information about
the last extent in the file as the hint to size our delalloc
reservation.
- it can tell us that we are writing into a hole, but that there is
an extent beyoned this hole. In this case we can create a
delalloc reservation that covers the requested size (possible
capped to the next existing allocation).
All that can be done in one single routine instead of bouncing up
and down a few layers. This reduced the CPU overhead of the block
mapping routines and also simplified the code a lot.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
For long growing file writes we will usually already have the
eofblocks tag set when adding more speculative preallocations. Add
a flag in the inode to allow us to skip the the fairly expensive
AG-wide spinlocks and multiple radix tree operations in that case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
And drop the pointless mp argument to xfs_iomap_eof_align_last_fsb,
while we're at it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We'll need it earlier in the file soon, so the unchanged function to
the top of xfs_iomap.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
One unfortunate quirk of the reference count and reverse mapping
btrees -- they can expand in size when blocks are written to *other*
allocation groups if, say, one large extent becomes a lot of tiny
extents. Since we don't want to start throwing errors in the middle
of CoWing, we need to reserve some blocks to handle future expansion.
The transaction block reservation counters aren't sufficient here
because we have to have a reserve of blocks in every AG, not just
somewhere in the filesystem.
Therefore, create two per-AG block reservation pools. One feeds the
AGFL so that rmapbt expansion always succeeds, and the other feeds all
other metadata so that refcountbt expansion never fails.
Use the count of how many reserved blocks we need to have on hand to
create a virtual reservation in the AG. Through selective clamping of
the maximum length of allocation requests and of the length of the
longest free extent, we can make it look like there's less free space
in the AG unless the reservation owner is asking for blocks.
In other words, play some accounting tricks in-core to make sure that
we always have blocks available. On the plus side, there's nothing to
clean up if we crash, which is contrast to the strategy that the rough
draft used (actually removing extents from the freespace btrees).
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When xfs_defer_finish calls ->finish_item, it's possible that
(refcount) won't be able to finish all the work in a single
transaction. When this happens, the ->finish_item handler should
shorten the log done item's list count, update the work item to
reflect where work should continue, and return -EAGAIN so that
defer_finish knows to retain the pending item on the pending list,
roll the transaction, and restart processing where we left off.
Plumb in the code and document how this mechanism is supposed to work.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Provide a helper method to count the number of blocks in a short form
btree. The refcount and rmap btrees need to know the number of blocks
already in use to set up their per-AG block reservations during mount.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Create a helper to generate AG btree height calculator functions.
This will be used (much) later when we get to the refcount btree.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Remove the xfs_btree_bigkey mess and simply make xfs_btree_key big enough
to hold both keys in-core.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Use variable length array declarations for RUI log items,
and replace the open coded sizeof formulae with a single function.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
As it stands today, the "fail immediately" vs. "retry forever"
values for max_retries and retry_timeout_seconds in the xfs metadata
error configurations are not consistent.
A retry_timeout_seconds of 0 means "retry forever," but a
max_retries of 0 means "fail immediately."
retry_timeout_seconds < 0 is disallowed, while max_retries == -1
means "retry forever."
Make this consistent across the error configs, such that a value of
0 means "fail immediately" (i.e. wait 0 seconds, or retry 0 times),
and a value of -1 always means "retry forever."
This makes retry_timeout a signed long to accommodate the -1, even
though it stores jiffies. Given our limit of a 1 day maximum
timeout, this should be sufficient even at much higher HZ values
than we have available today.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Commit 2a6fba6 "xfs: only return -errno or success from attr ->put_listent"
changes the returnvalue of __xfs_xattr_put_listen to 0 in case when there is
insufficient space in the buffer assuming that setting context->count to -1
would be enough, but all of the ->put_listent callers only check seen_enough.
This results in a failed assertion:
XFS: Assertion failed: context->count >= 0, file: fs/xfs/xfs_xattr.c, line: 175
in insufficient buffer size case.
This is only reproducible with at least 2 xattrs and only when the buffer
gets depleted before the last one.
Furthermore if buffersize is such that it is enough to hold the last xattr's
name, but not enough to hold the sum of preceeding xattr names listxattr won't
fail with ERANGE, but will suceed returning last xattr's name without the
first character. The first character end's up overwriting data stored at
(context->alist - 1).
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
"blocks" should be added back to fdblocks at undo time, not taken
away, i.e. the minus sign should not be used.
This is a regression introduced by commit 0d485ada40 ("xfs: use
generic percpu counters for free block counter"). And it's found by
code inspection, I didn't it in real world, so there's no
reproducer.
Signed-off-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Christoph reports slab corruption when a deferred refcount update
aborts during _defer_finish(). The cause of this was broken log item
state tracking in xfs_defer_pending -- upon an abort,
_defer_trans_abort() will call abort_intent on all intent items,
including the ones that have already had a done item attached.
This is incorrect because each intent item has 2 refcount: the first
is released when the intent item is committed to the log; and the
second is released when the _done_ item is committed to the log, or
by the intent creator if there is no done item. In other words, once
we log the done item, responsibility for releasing the intent item's
second refcount is transferred to the done item and /must not/ be
performed by anything else.
The dfp_committed flag should have been tracking whether or not we had
a done item so that _defer_trans_abort could decide if it needs to
abort the intent item, but due to a thinko this was not the case. Rip
it out and track the done item directly so that we do the right thing
w.r.t. intent item freeing.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reported-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_wait_buftarg() waits for all pending I/O, drains the ioend
completion workqueue and walks the LRU until all buffers in the cache
have been released. This is traditionally an unmount operation` but the
mechanism is also reused during filesystem freeze.
xfs_wait_buftarg() invokes drain_workqueue() as part of the quiesce,
which is intended more for a shutdown sequence in that it indicates to
the queue that new operations are not expected once the drain has begun.
New work jobs after this point result in a WARN_ON_ONCE() and are
otherwise dropped.
With filesystem freeze, however, read operations are allowed and can
proceed during or after the workqueue drain. If such a read occurs
during the drain sequence, the workqueue infrastructure complains about
the queued ioend completion work item and drops it on the floor. As a
result, the buffer remains on the LRU and the freeze never completes.
Despite the fact that the overall buffer cache cleanup is not necessary
during freeze, fix up this operation such that it is safe to invoke
during non-unmount quiesce operations. Replace the drain_workqueue()
call with flush_workqueue(), which runs a similar serialization on
pending workqueue jobs without causing new jobs to be dropped. This is
safe for unmount as unmount independently locks out new operations by
the time xfs_wait_buftarg() is invoked.
cc: <stable@vger.kernel.org>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
From inspection, the superblock sb_inprogress check is done in the
verifier and triggered only for the primary superblock via a
"bp->b_bn == XFS_SB_DADDR" check.
Unfortunately, the primary superblock is an uncached buffer, and
hence it is configured by xfs_buf_read_uncached() with:
bp->b_bn = XFS_BUF_DADDR_NULL; /* always null for uncached buffers */
And so this check never triggers. Fix it.
cc: <stable@vger.kernel.org>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If the initial LOOKUP_LE in the simple query range fails to find
anything, we should attempt to increment the btree cursor to see
if there actually /are/ records for what we're trying to find.
Without this patch, a bnobt range query of (0, $agsize) returns
no results because the leftmost record never has a startblock
of zero.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We only need the record's high key for the first record that we look
at; for all records, we /definitely/ need the regular record key.
Therefore, fix how the simple range query function gets its keys.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we're logging the last non-spare field in the AGF, we don't
need to log the spare fields, so plumb in a new AGF logging flag
to help us avoid that.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Since the kernel doesn't currently support the realtime rmapbt,
don't allow such filesystems to be mounted. Support will appear
in a future release.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If the caller passes in a cursor to a zero-height btree (which is
impossible), we never set block to anything but NULL, which causes the
later dereference of it to crash. Instead, just return -EFSCORRUPTED.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we're really tight on space, xfs_alloc_ag_vextent_small() can
allocate a block from the AGFL and give it to the caller. Since the
caller is never the AGFL-fixing method, we must remove the OWN_AG
reverse mapping because it will clash with whatever rmap the caller
wants to set up. This bug was discovered by running generic/299
repeatedly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Use a special read-only iomap_ops implementation to support fiemap on
the attr fork.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We'll never get nimap == 0 for a successful return from xfs_bmapi_read,
so don't try to handle it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Track the number of blocks used for the rmapbt in the AGF. When we
get to the AG reservation code we need this counter to quickly
make our reservation during mount.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we do DAX IO, we try to invalidate the entire page cache held
on the file. This is incorrect as it will trash the entire mapping
tree that now tracks dirty state in exceptional entries in the radix
tree slots.
What we are trying to do is remove cached pages (e.g from reads
into holes) that sit in the radix tree over the range we are about
to write to. Hence we should just limit the invalidation to the
range we are about to overwrite.
Reported-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The space reservations was without an explaination in commit
"Add error reporting calls in error paths that return EFSCORRUPTED"
back in 2003. There is no reason to reserve disk blocks in the
transaction when allocating blocks for delalloc space as we already
reserved the space when creating the delalloc extent.
With this fix we stop running out of the reserved pool in
generic/229, which has happened for long time with small blocksize
file systems, and has increased in severity with the new buffered
write path.
[ dchinner: we still need to pass the block reservation into
xfs_bmapi_write() to ensure we don't deadlock during AG selection.
See commit dbd5c8c ("xfs: pass total block res. as total
xfs_bmapi_write() parameter") for more details on why this is
necessary. ]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The buffer I/O accounting mechanism tracks async buffers under I/O. As
an optimization, the buffer I/O count is incremented only once on the
first async I/O for a given hold cycle of a buffer and decremented once
the buffer is released to the LRU (or freed).
xfs_buf_ioacct_dec() has an ASSERT() check for an XBF_ASYNC buffer, but
we have one or two corner cases where a buffer can be submitted for I/O
multiple times via different methods in a single hold cycle. If an async
I/O occurs first, the I/O count is incremented. If a sync I/O occurs
before the hold count drops, XBF_ASYNC is cleared by the time the I/O
count is decremented.
Remove the async assert check from xfs_buf_ioacct_dec() as this is a
perfectly valid scenario. For the purposes of I/O accounting, we really
only care about the buffer async state at I/O submission time.
Discovered-and-analyzed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In most cases, EPERM is returned on immutable inode, and there're only a
few places returning EACCES. I noticed this when running LTP on
overlayfs, setxattr03 failed due to unexpected EACCES on immutable
inode.
So converting all EACCES to EPERM on immutable inode.
Acked-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Merge tag 'xfs-rmap-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull more xfs updates from Dave Chinner:
"This is the second part of the XFS updates for this merge cycle, and
contains the new reverse block mapping feature for XFS.
Reverse mapping allows us to track the owner of a specific block on
disk precisely. It is implemented as a set of btrees (one per
allocation group) that track the owners of allocated extents.
Effectively it is a "used space tree" that is updated when we allocate
or free extents. i.e. it is coherent with the free space btrees we
already maintain and never overlaps with them.
This reverse mapping infrastructure is the building block of several
upcoming features - reflink, copy-on-write data, dedupe, online
metadata and data scrubbing, highly accurate bad sector/data loss
reporting to users, and significantly improved reconstruction of
damaged and corrupted filesystems. There's a lot of new stuff coming
along in the next couple of cycles,a nd it all builds in the rmap
infrastructure.
As such, it's a huge chunk of new code with new on-disk format
features and internal infrastructure. It warns at mount time as an
experimental feature and that it may eat data (as we do with all new
on-disk features until they stabilise). We have not released
userspace suport for it yet - userspace support currently requires
download from Darrick's xfsprogs repo and build from source, so the
access to this feature is really developer/tester only at this point.
Initial userspace support will be released at the same time kernel
with this code in it is released.
The new rmap enabled code regresses 3 xfstests - all are ENOSPC
related corner cases, one of which Darrick posted a fix for a few
hours ago. The other two are fixed by infrastructure that is part of
the upcoming reflink patchset. This new ENOSPC infrastructure
requires a on-disk format tweak required to keep mount times in
check - we need to keep an on-disk count of allocated rmapbt blocks so
we don't have to scan the entire btrees at mount time to count them.
This is currently being tested and will be part of the fixes sent in
the next week or two so users will not be exposed to this change"
* tag 'xfs-rmap-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (52 commits)
xfs: move (and rename) the deferred bmap-free tracepoints
xfs: collapse single use static functions
xfs: remove unnecessary parentheses from log redo item recovery functions
xfs: remove the extents array from the rmap update done log item
xfs: in btree_lshift, only allocate temporary cursor when needed
xfs: remove unnecesary lshift/rshift key initialization
xfs: remove the get*keys and update_keys btree ops pointers
xfs: enable the rmap btree functionality
xfs: don't update rmapbt when fixing agfl
xfs: disable XFS_IOC_SWAPEXT when rmap btree is enabled
xfs: add rmap btree block detection to log recovery
xfs: add rmap btree geometry feature flag
xfs: propagate bmap updates to rmapbt
xfs: enable the xfs_defer mechanism to process rmaps to update
xfs: log rmap intent items
xfs: create rmap update intent log items
xfs: add rmap btree insert and delete helpers
xfs: convert unwritten status of reverse mappings
xfs: remove an extent from the rmap btree
xfs: add an extent to the rmap btree
...
Trond made a change to the server's tcp logic that allows a fast
client to better take advantage of high bandwidth networks, but
may increase the risk that a single client could starve other
clients; a new sunrpc.svc_rpc_per_connection_limit parameter
should help mitigate this in the (hopefully unlikely) event this
becomes a problem in practice.
Tom Haynes added a minimal flex-layout pnfs server, which is of
no use in production for now--don't build it unless you're doing
client testing or further server development.
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Merge tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
"Highlights:
- Trond made a change to the server's tcp logic that allows a fast
client to better take advantage of high bandwidth networks, but may
increase the risk that a single client could starve other clients;
a new sunrpc.svc_rpc_per_connection_limit parameter should help
mitigate this in the (hopefully unlikely) event this becomes a
problem in practice.
- Tom Haynes added a minimal flex-layout pnfs server, which is of no
use in production for now--don't build it unless you're doing
client testing or further server development"
* tag 'nfsd-4.8' of git://linux-nfs.org/~bfields/linux: (32 commits)
nfsd: remove some dead code in nfsd_create_locked()
nfsd: drop unnecessary MAY_EXEC check from create
nfsd: clean up bad-type check in nfsd_create_locked
nfsd: remove unnecessary positive-dentry check
nfsd: reorganize nfsd_create
nfsd: check d_can_lookup in fh_verify of directories
nfsd: remove redundant zero-length check from create
nfsd: Make creates return EEXIST instead of EACCES
SUNRPC: Detect immediate closure of accepted sockets
SUNRPC: accept() may return sockets that are still in SYN_RECV
nfsd: allow nfsd to advertise multiple layout types
nfsd: Close race between nfsd4_release_lockowner and nfsd4_lock
nfsd/blocklayout: Make sure calculate signature/designator length aligned
xfs: abstract block export operations from nfsd layouts
SUNRPC: Remove unused callback xpo_adjust_wspace()
SUNRPC: Change TCP socket space reservation
SUNRPC: Add a server side per-connection limit
SUNRPC: Micro optimisation for svc_data_ready
SUNRPC: Call the default socket callbacks instead of open coding
SUNRPC: lock the socket while detaching it
...
Rename the deferred bmap-free to extent_free and make them only
trigger when we're really running deferred ops.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Nothing ever uses the extent array in the rmap update done redo
item, so remove it before it is fixed in the on-disk log format.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We only need the temporary cursor in _btree_lshift if we're shifting
in an overlapped btree. Therefore, factor that into a single block
of code so we avoid unnecessary cursor duplication.
Also fix use of the wrong cursor when checking for corruption in
xfs_btree_rshift().
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In the lshift/rshift functions we don't use the key variable for
anything now, so remove the variable and its initializer. The
update_keys functions figure out the key for a block on their own.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
These are internal btree functions; we don't need them to be
dispatched via function pointers. Make them static again and
just check the overlapped flag to figure out what we need to
do. The strategy behind this patch was suggested by Christoph.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Add the feature flag to the supported matrix so that the kernel can
mount and use rmap btree enabled filesystems
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[darrick.wong@oracle.com: move the experimental tag]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Allow a caller of xfs_alloc_fix_freelist to disable rmapbt updates
when fixing the AG freelist. xfs_repair needs this during phase 5
to be able to adjust the freelist while it's reconstructing the rmap
btree; the missing entries will be added back at the very end of
phase 5 once the AGFL contents settle down.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Swapping extents between two inodes requires the owner to be updated
in the rmap tree for all the extents that are swapped. This code
does not yet exist, so switch off the XFS_IOC_SWAPEXT ioctl until
support has been implemented. This will need to be done before the
rmap btree code can have the experimental tag removed.
This functionality will be provided in a (much) later patch, using
some of the reflink deferred block remapping functionality to
accomlish extent swapping with rmap updates.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
So such blocks can be correctly identified and have their operations
structures attached to validate recovery has not resulted in a
correct block.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
So xfs_info and other userspace utilities know the filesystem is
using this feature.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we map, unmap, or convert an extent in a file's data or attr
fork, schedule a respective update in the rmapbt. Previous versions
of this patch required a 1:1 correspondence between bmap and rmap,
but this is no longer true as we now have ability to make interval
queries against the rmapbt.
We use the deferred operations code to handle redo operations
atomically and deadlock free. This plumbs in all five rmap actions
(map, unmap, convert extent, alloc, free); we'll use the first three
now for file data, and reflink will want the last two. We also add
an error injection site to test log recovery.
Finally, we need to fix the bmap shift extent code to adjust the
rmaps correctly.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Connect the xfs_defer mechanism with the pieces that we'll need to
handle deferred rmap updates. We'll wire up the existing code to
our new deferred mechanism later.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Provide a mechanism for higher levels to create RUI/RUD items, submit
them to the log, and a stub function to deal with recovered RUI items.
These parts will be connected to the rmapbt in a later patch.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Create rmap update intent/done log items to record redo information in
the log. Because we need to roll transactions between updating the
bmbt mapping and updating the reverse mapping, we also have to track
the status of the metadata updates that will be recorded in the
post-roll transactions, just in case we crash before committing the
final transaction. This mechanism enables log recovery to finish what
was already started.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add a couple of helper functions to encapsulate rmap btree insert and
delete operations. Add tracepoints to the update function.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Provide a function to convert an unwritten rmap extent to a real one
and vice versa.
[ dchinner: Note that this algorithm and code was derived from the
existing bmapbt unwritten extent conversion code in
xfs_bmap_add_extent_unwritten_real(). ]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Now that we have records in the rmap btree, we need to remove them
when extents are freed. This needs to find the relevant record in
the btree and remove/trim/split it accordingly.
[darrick.wong@oracle.com: make rmap routines handle the enlarged keyspace]
[dchinner: remove remaining unused debug printks]
[darrick: fix a bug when growfs in an AG with an rmap ending at EOFS]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Now all the btree, free space and transaction infrastructure is in
place, we can finally add the code to insert reverse mappings to the
rmap btree. Freeing will be done in a separate patch, so just the
addition operation can be focussed on here.
[darrick: handle owner offsets when adding rmaps]
[dchinner: remove remaining debug printk statements]
[darrick: move unwritten bit to rm_offset]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Now that the generic btree code supports querying all records within a
range of keys, use that functionality to allow us to ask for all the
extents mapped to a range of physical blocks.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Now that the generic btree code supports overlapping intervals, plug
in the rmap btree to this functionality. We will need it to find
potential left neighbors in xfs_rmap_{alloc,free} later in the patch
set.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Implement the generic btree operations needed to manipulate rmap
btree blocks. This is very similar to the per-ag freespace btree
implementation, and uses the AGFL for allocation and freeing of
blocks.
Adapt the rmap btree to store owner offsets within each rmap record,
and to handle the primary key being redefined as the tuple
[agblk, owner, offset]. The expansion of the primary key is crucial
to allowing multiple owners per extent.
[darrick: adapt the btree ops to deal with offsets]
[darrick: remove init_rec_from_key]
[darrick: move unwritten bit to rm_offset]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
The rmap btree is allocated from the AGFL, which means we have to
ensure ENOSPC is reported to userspace before we run out of free
space in each AG. The last allocation in an AG can cause a full
height rmap btree split, and that means we have to reserve at least
this many blocks *in each AG* to be placed on the AGFL at ENOSPC.
Update the various space calculation functions to handle this.
Also, because the macros are now executing conditional code and are
called quite frequently, convert them to functions that initialise
variables in the struct xfs_mount, use the new variables everywhere
and document the calculations better.
[darrick.wong@oracle.com: don't reserve blocks if !rmap]
[dchinner@redhat.com: update m_ag_max_usable after growfs]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The rmap btrees will use the AGFL as the block allocation source, so
we need to ensure that the transaction reservations reflect the fact
this tree is modified by allocation and freeing. Hence we need to
extend all the extent allocation/free reservations used in
transactions to handle this.
Note that this also gets rid of the unused XFS_ALLOCFREE_LOG_RES
macro, as we now do buffer reservations based on the number of
buffers logged via xfs_calc_buf_res(). Hence we only need the buffer
count calculation now.
[darrick: use rmap_maxlevels when calculating log block resv]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Now we can read and write rmap btree blocks, we can add support to
the growfs code to initialise new rmap btree blocks.
[darrick.wong@oracle.com: fill out the rmap offset fields]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Now we have all the surrounding call infrastructure in place, we can
start filling out the rmap btree implementation. Start with the
on-disk btree format; add everything needed to read, write and
manipulate rmap btree blocks. This prepares the way for adding the
btree operations implementation.
[darrick: record owner and offset info in rmap btree]
[darrick: fork, bmbt and unwritten state in rmap btree]
[darrick: flags are a separate field in xfs_rmap_irec]
[darrick: calculate maxlevels separately]
[darrick: move the 'unwritten' bit into unused parts of rm_offset]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Add the stubs into the extent allocation and freeing paths that the
rmap btree implementation will hook into. While doing this, add the
trace points that will be used to track rmap btree extent
manipulations.
[darrick.wong@oracle.com: Extend the stubs to take full owner info.]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
For the rmap btree to work, we have to feed the extent owner
information to the the allocation and freeing functions. This
information is what will end up in the rmap btree that tracks
allocated extents. While we technically don't need the owner
information when freeing extents, passing it allows us to validate
that the extent we are removing from the rmap btree actually
belonged to the owner we expected it to belong to.
We also define a special set of owner values for internal metadata
that would otherwise have no owner. This allows us to tell the
difference between metadata owned by different per-ag btrees, as
well as static fs metadata (e.g. AG headers) and internal journal
blocks.
There are also a couple of special cases we need to take care of -
during EFI recovery, we don't actually know who the original owner
was, so we need to pass a wildcard to indicate that we aren't
checking the owner for validity. We also need special handling in
growfs, as we "free" the space in the last AG when extending it, but
because it's new space it has no actual owner...
While touching the xfs_bmap_add_free() function, re-order the
parameters to put the struct xfs_mount first.
Extend the owner field to include both the owner type and some sort
of index within the owner. The index field will be used to support
reverse mappings when reflink is enabled.
When we're freeing extents from an EFI, we don't have the owner
information available (rmap updates have their own redo items).
xfs_free_extent therefore doesn't need to do an rmap update. Make
sure that the log replay code signals this correctly.
This is based upon a patch originally from Dave Chinner. It has been
extended to add more owner information with the intent of helping
recovery operations when things go wrong (e.g. offset of user data
block in a file).
[dchinner: de-shout the xfs_rmap_*_owner helpers]
[darrick: minor style fixes suggested by Christoph Hellwig]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
XFS reserves a small amount of space in each AG for the minimum
number of free blocks needed for operation. Adding the rmap btree
increases the number of reserved blocks, but it also increases the
complexity of the calculation as the free inode btree is optional
(like the rmbt).
Rather than calculate the prealloc blocks every time we need to
check it, add a function to calculate it at mount time and store it
in the struct xfs_mount, and convert the XFS_PREALLOC_BLOCKS macro
just to use the xfs-mount variable directly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
The rmap btree will require the same stats as all the other generic
btrees, so add all the code for that now.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Originally-From: Dave Chinner <dchinner@redhat.com>
Add new per-ag rmap btree definitions to the per-ag structures. The
rmap btree will sit in the empty slots on disk after the free space
btrees, and hence form a part of the array of space management
btrees. This requires the definition of the btree to be contiguous
with the free space btrees.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
By my calculations, a 1,073,741,824 block AG with a 1k block size
can attain a maximum height of 9. Assuming a record size of 24
bytes, a key/ptr size of 44 bytes, and half-full btree nodes, we'd
need 53,687,092 blocks for the records and ~6 million blocks for the
keys. That requires a btree of height 9 based on the following
derivation:
Block size = 1024b
sblock CRC header = 56b
== 1024-56 = 968 bytes for tree data
rmapbt record = 24b
== 40 records per leaf block
rmapbt ptr/key = 44b
== 22 ptr/keys per block
Worst case, each block is half full, so 20 records and 11 ptrs per block.
1073741824 rmap records / 20 records per block
== 53687092 leaf blocks
53687092 leaves / 11 ptrs per block
== 4880645 level 1 blocks
== 443695 level 2 blocks
== 40336 level 3 blocks
== 3667 level 4 blocks
== 334 level 5 blocks
== 31 level 6 blocks
== 3 level 7 blocks
== 1 level 8 block
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add a couple of tracepoints for the deferred extent free operation and
a site for injecting errors while finishing the operation. This makes
it easier to debug deferred ops and test log redo.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Refactor the EFI intent item recovery (and cancellation) functions
into a general function that scans the AIL and an intent item type
specific handler. Move the function that recovers a single EFI item
into the extent free item code. We'll want the generalized function
when we start wiring up more redo item types.
Furthermore, ensure that log recovery only replays the redo items
that were in the AIL prior to recovery by checking the item LSN
against the largest LSN seen during log scanning. As written this
should never happen, but we can be defensive anyway.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Mechanical change of flist/free_list to dfops, since they're now
deferred ops, not just a freeing list.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Drop the compatibility shims that we were using to integrate the new
deferred operation mechanism into the existing code. No new code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Restructure everything that used xfs_bmap_free to use xfs_defer_ops
instead. For now we'll just remove the old symbols and play some
cpp magic to make it work; in the next patch we'll actually rename
everything.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Connect the xfs_defer mechanism with the pieces that we'll need to
handle deferred extent freeing. We'll wire up the existing code to
our new deferred mechanism later.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Replace structure typedefs with struct xfs_foo_* in the EFI/EFD
handling code in preparation to move it over to deferred ops.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add tracepoints for the internals of the deferred ops mechanism
and tracepoint classes for clients of the dops, to make debugging
easier.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
All the code around struct xfs_bmap_free basically implements a
deferred operation framework through which we can roll transactions
(to unlock buffers and avoid violating lock order rules) while
managing all the necessary log redo items. Previously we only used
this code to free extents after some sort of mapping operation, but
with the advent of rmap and reflink, we suddenly need to do more than
that.
With that in mind, xfs_bmap_free really becomes a deferred ops control
structure. Rename the structure and move the deferred ops into their
own file to avoid further bloating of the bmap code.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Refactor the btree_change_owner function into a more generic apparatus
which visits all blocks in a btree. We'll use this in a subsequent
patch for counting btree blocks for AG reservations.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Create a function to enable querying of btree records mapping to a
range of keys. This will be used in subsequent patches to allow
querying the reverse mapping btree to find the extents mapped to a
range of physical blocks, though the generic code can be used for
any range query.
The overlapped query range function needs to use the btree get_block
helper because the root block could be an inode, in which case
bc_bufs[nlevels-1] will be NULL.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
On a filesystem with both reflink and reverse mapping enabled, it's
possible to have multiple rmap records referring to the same blocks on
disk. When overlapping intervals are possible, querying a classic
btree to find all records intersecting a given interval is inefficient
because we cannot use the left side of the search interval to filter
out non-matching records the same way that we can use the existing
btree key to filter out records coming after the right side of the
search interval. This will become important once we want to use the
rmap btree to rebuild BMBTs, or implement the (future) fsmap ioctl.
(For the non-overlapping case, we can perform such queries trivially
by starting at the left side of the interval and walking the tree
until we pass the right side.)
Therefore, extend the btree code to come closer to supporting
intervals as a first-class record attribute. This involves widening
the btree node's key space to store both the lowest key reachable via
the node pointer (as the btree does now) and the highest key reachable
via the same pointer and teaching the btree modifying functions to
keep the highest-key records up to date.
This behavior can be turned on via a new btree ops flag so that btrees
that cannot store overlapping intervals don't pay the overhead costs
in terms of extra code and disk format changes.
When we're deleting a record in a btree that supports overlapped
interval records and the deletion results in two btree blocks being
joined, we defer updating the high/low keys until after all possible
joining (at higher levels in the tree) have finished. At this point,
the btree pointers at all levels have been updated to remove the empty
blocks and we can update the low and high keys.
When we're doing this, we must be careful to update the keys of all
node pointers up to the root instead of stopping at the first set of
keys that don't need updating. This is because it's possible for a
single deletion to cause joining of multiple levels of tree, and so
we need to update everything going back to the root.
The diff_two_keys functions return < 0, 0, or > 0 if key1 is less than,
equal to, or greater than key2, respectively. This is consistent
with the rest of the kernel and the C library.
In btree_updkeys(), we need to evaluate the force_all parameter before
running the key diff to avoid reading uninitialized memory when we're
forcing a key update. This happens when we've allocated an empty slot
at level N + 1 to point to a new block at level N and we're in the
process of filling out the new keys.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add some function pointers to bc_ops to get the btree keys for
leaf and node blocks, and to update parent keys of a block.
Convert the _btree_updkey calls to use our new pointer, and
modify the tree shape changing code to call the appropriate
get_*_keys pointer instead of _btree_copy_keys because the
overlapping btree has to calculate high key values.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When a btree block has to be split, we pass the new block's ptr from
xfs_btree_split() back to xfs_btree_insert() via a pointer parameter;
however, we pass the block's key through the cursor's record. It is a
little weird to "initialize" a record from a key since the non-key
attributes will have garbage values.
When we go to add support for interval queries, we have to be able to
pass the lowest and highest keys accessible via a pointer. There's no
clean way to pass this back through the cursor's record field.
Therefore, pass the key directly back to xfs_btree_insert() the same
way that we pass the btree_ptr.
As a bonus, we no longer need init_rec_from_key and can drop it from the
codebase.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If we make the inode root block of a btree unfull by expanding the
root, we must set *stat to 1 to signal success, rather than leaving
it uninitialized.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we're deleting realtime extents, we need to lock the summary
inode in case we need to update the summary info to prevent an assert
on the rsumip inode lock on a debug kernel. While we're at it, fix
the locking annotations so that we avoid triggering lockdep warnings.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Apparently cris doesn't require structure stride to align with the
largest type in the struct, so list[0] isn't at offset 4 like it is
everywhere else. Fix this... insofar as existing XFSes on cris are
screwed.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When we're iterating inode xattrs by handle, we have to copy the
cursor back to userspace so that a subsequent invocation actually
retrieves subsequent contents.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Pull vfs updates from Al Viro:
"Assorted cleanups and fixes.
Probably the most interesting part long-term is ->d_init() - that will
have a bunch of followups in (at least) ceph and lustre, but we'll
need to sort the barrier-related rules before it can get used for
really non-trivial stuff.
Another fun thing is the merge of ->d_iput() callers (dentry_iput()
and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
except the one in __d_lookup_lru())"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
fs/dcache.c: avoid soft-lockup in dput()
vfs: new d_init method
vfs: Update lookup_dcache() comment
bdev: get rid of ->bd_inodes
Remove last traces of ->sync_page
new helper: d_same_name()
dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
vfs: clean up documentation
vfs: document ->d_real()
vfs: merge .d_select_inode() into .d_real()
unify dentry_iput() and dentry_unlink_inode()
binfmt_misc: ->s_root is not going anywhere
drop redundant ->owner initializations
ufs: get rid of redundant checks
orangefs: constify inode_operations
missed comment updates from ->direct_IO() prototype change
file_inode(f)->i_mapping is f->f_mapping
trim fsnotify hooks a bit
9p: new helper - v9fs_parent_fid()
debugfs: ->d_parent is never NULL or negative
...
Changes in this update:
o generic iomap based IO path infrastructure
o generic iomap based fiemap implementation
o xfs iomap based Io path implementation
o buffer error handling fixes
o tracking of in flight buffer IO for unmount serialisation
o direct IO and DAX io path separation and simplification
o shortform directory format definition changes for wider platform compatibility
o various buffer cache fixes
o cleanups in preparation for rmap merge
o error injection cleanups and fixes
o log item format buffer memory allocation restructuring to prevent rare OOM
reclaim deadlocks
o sparse inode chunks are now fully supported.
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Merge tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs updates from Dave Chinner:
"The major addition is the new iomap based block mapping
infrastructure. We've been kicking this about locally for years, but
there are other filesystems want to use it too (e.g. gfs2). Now it
is fully working, reviewed and ready for merge and be used by other
filesystems.
There are a lot of other fixes and cleanups in the tree, but those are
XFS internal things and none are of the scale or visibility of the
iomap changes. See below for details.
I am likely to send another pull request next week - we're just about
ready to merge some new functionality (on disk block->owner reverse
mapping infrastructure), but that's a huge chunk of code (74 files
changed, 7283 insertions(+), 1114 deletions(-)) so I'm keeping that
separate to all the "normal" pull request changes so they don't get
lost in the noise.
Summary of changes in this update:
- generic iomap based IO path infrastructure
- generic iomap based fiemap implementation
- xfs iomap based Io path implementation
- buffer error handling fixes
- tracking of in flight buffer IO for unmount serialisation
- direct IO and DAX io path separation and simplification
- shortform directory format definition changes for wider platform
compatibility
- various buffer cache fixes
- cleanups in preparation for rmap merge
- error injection cleanups and fixes
- log item format buffer memory allocation restructuring to prevent
rare OOM reclaim deadlocks
- sparse inode chunks are now fully supported"
* tag 'xfs-for-linus-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (53 commits)
xfs: remove EXPERIMENTAL tag from sparse inode feature
xfs: bufferhead chains are invalid after end_page_writeback
xfs: allocate log vector buffers outside CIL context lock
libxfs: directory node splitting does not have an extra block
xfs: remove dax code from object file when disabled
xfs: skip dirty pages in ->releasepage()
xfs: remove __arch_pack
xfs: kill xfs_dir2_inou_t
xfs: kill xfs_dir2_sf_off_t
xfs: split direct I/O and DAX path
xfs: direct calls in the direct I/O path
xfs: stop using generic_file_read_iter for direct I/O
xfs: split xfs_file_read_iter into buffered and direct I/O helpers
xfs: remove s_maxbytes enforcement in xfs_file_read_iter
xfs: kill ioflags
xfs: don't pass ioflags around in the ioctl path
xfs: track and serialize in-flight async buffers against unmount
xfs: exclude never-released buffers from buftarg I/O accounting
xfs: don't reset b_retries to 0 on every failure
xfs: remove extraneous buffer flag changes
...
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2
- most(?) of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits)
thp: fix comments of __pmd_trans_huge_lock()
cgroup: remove unnecessary 0 check from css_from_id()
cgroup: fix idr leak for the first cgroup root
mm: memcontrol: fix documentation for compound parameter
mm: memcontrol: remove BUG_ON in uncharge_list
mm: fix build warnings in <linux/compaction.h>
mm, thp: convert from optimistic swapin collapsing to conservative
mm, thp: fix comment inconsistency for swapin readahead functions
thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
shmem: split huge pages beyond i_size under memory pressure
thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
khugepaged: add support of collapse for tmpfs/shmem pages
shmem: make shmem_inode_info::lock irq-safe
khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
thp: extract khugepaged from mm/huge_memory.c
shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
shmem: add huge pages support
shmem: get_unmapped_area align huge page
shmem: prepare huge= mount option and sysfs knob
mm, rmap: account shmem thp pages
...
Remove the unused wrappers dax_fault() and dax_pmd_fault(). After this
removal, rename __dax_fault() and __dax_pmd_fault() to dax_fault() and
dax_pmd_fault() respectively, and update all callers.
The dax_fault() and dax_pmd_fault() wrappers were initially intended to
capture some filesystem independent functionality around page faults
(calling sb_start_pagefault() & sb_end_pagefault(), updating file mtime
and ctime).
However, the following commits:
5726b27b09 ("ext2: Add locking for DAX faults")
ea3d7209ca ("ext4: fix races between page faults and hole punching")
added locking to the ext2 and ext4 filesystems after these common
operations but before __dax_fault() and __dax_pmd_fault() were called.
This means that these wrappers are no longer used, and are unlikely to
be used in the future.
XFS has had locking analogous to what was recently added to ext2 and
ext4 since DAX support was initially introduced by:
6b698edeee ("xfs: add DAX file operations support")
Link: http://lkml.kernel.org/r/20160714214049.20075-2-ross.zwisler@linux.intel.com
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Chinner <david@fromorbit.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull core block updates from Jens Axboe:
- the big change is the cleanup from Mike Christie, cleaning up our
uses of command types and modified flags. This is what will throw
some merge conflicts
- regression fix for the above for btrfs, from Vincent
- following up to the above, better packing of struct request from
Christoph
- a 2038 fix for blktrace from Arnd
- a few trivial/spelling fixes from Bart Van Assche
- a front merge check fix from Damien, which could cause issues on
SMR drives
- Atari partition fix from Gabriel
- convert cfq to highres timers, since jiffies isn't granular enough
for some devices these days. From Jan and Jeff
- CFQ priority boost fix idle classes, from me
- cleanup series from Ming, improving our bio/bvec iteration
- a direct issue fix for blk-mq from Omar
- fix for plug merging not involving the IO scheduler, like we do for
other types of merges. From Tahsin
- expose DAX type internally and through sysfs. From Toshi and Yigal
* 'for-4.8/core' of git://git.kernel.dk/linux-block: (76 commits)
block: Fix front merge check
block: do not merge requests without consulting with io scheduler
block: Fix spelling in a source code comment
block: expose QUEUE_FLAG_DAX in sysfs
block: add QUEUE_FLAG_DAX for devices to advertise their DAX support
Btrfs: fix comparison in __btrfs_map_block()
block: atari: Return early for unsupported sector size
Doc: block: Fix a typo in queue-sysfs.txt
cfq-iosched: Charge at least 1 jiffie instead of 1 ns
cfq-iosched: Fix regression in bonnie++ rewrite performance
cfq-iosched: Convert slice_resid from u64 to s64
block: Convert fifo_time from ulong to u64
blktrace: avoid using timespec
block/blk-cgroup.c: Declare local symbols static
block/bio-integrity.c: Add #include "blk.h"
block/partition-generic.c: Remove a set-but-not-used variable
block: bio: kill BIO_MAX_SIZE
cfq-iosched: temporarily boost queue priority for idle classes
block: drbd: avoid to use BIO_MAX_SIZE
block: bio: remove BIO_MAX_SECTORS
...
Been around for long enough now, hasn't caused any regression test
failures in the past 3 months, so it's time to make it a fully
supported feature.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In xfs_finish_page_writeback(), we have a loop that looks like this:
do {
if (off < bvec->bv_offset)
goto next_bh;
if (off > end)
break;
bh->b_end_io(bh, !error);
next_bh:
off += bh->b_size;
} while ((bh = bh->b_this_page) != head);
The b_end_io function is end_buffer_async_write(), which will call
end_page_writeback() once all the buffers have marked as no longer
under IO. This issue here is that the only thing currently
protecting both the bufferhead chain and the page from being
reclaimed is the PageWriteback state held on the page.
While we attempt to limit the loop to just the buffers covered by
the IO, we still read from the buffer size and follow the next
pointer in the bufferhead chain. There is no guarantee that either
of these are valid after the PageWriteback flag has been cleared.
Hence, loops like this are completely unsafe, and result in
use-after-free issues. One such problem was caught by Calvin Owens
with KASAN:
.....
INFO: Freed in 0x103fc80ec age=18446651500051355200 cpu=2165122683 pid=-1
free_buffer_head+0x41/0x90
__slab_free+0x1ed/0x340
kmem_cache_free+0x270/0x300
free_buffer_head+0x41/0x90
try_to_free_buffers+0x171/0x240
xfs_vm_releasepage+0xcb/0x3b0
try_to_release_page+0x106/0x190
shrink_page_list+0x118e/0x1a10
shrink_inactive_list+0x42c/0xdf0
shrink_zone_memcg+0xa09/0xfa0
shrink_zone+0x2c3/0xbc0
.....
Call Trace:
<IRQ> [<ffffffff81e8b8e4>] dump_stack+0x68/0x94
[<ffffffff8153a995>] print_trailer+0x115/0x1a0
[<ffffffff81541174>] object_err+0x34/0x40
[<ffffffff815436e7>] kasan_report_error+0x217/0x530
[<ffffffff81543b33>] __asan_report_load8_noabort+0x43/0x50
[<ffffffff819d651f>] xfs_destroy_ioend+0x3bf/0x4c0
[<ffffffff819d69d4>] xfs_end_bio+0x154/0x220
[<ffffffff81de0c58>] bio_endio+0x158/0x1b0
[<ffffffff81dff61b>] blk_update_request+0x18b/0xb80
[<ffffffff821baf57>] scsi_end_request+0x97/0x5a0
[<ffffffff821c5558>] scsi_io_completion+0x438/0x1690
[<ffffffff821a8d95>] scsi_finish_command+0x375/0x4e0
[<ffffffff821c3940>] scsi_softirq_done+0x280/0x340
Where the access is occuring during IO completion after the buffer
had been freed from direct memory reclaim.
Prevent use-after-free accidents in this end_io processing loop by
pre-calculating the loop conditionals before calling bh->b_end_io().
The loop is already limited to just the bufferheads covered by the
IO in progress, so the offset checks are sufficient to prevent
accessing buffers in the chain after end_page_writeback() has been
called by the the bh->b_end_io() callout.
Yet another example of why Bufferheads Must Die.
cc: <stable@vger.kernel.org> # 4.7
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reported-and-Tested-by: Calvin Owens <calvinowens@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
One of the problems we currently have with delayed logging is that
under serious memory pressure we can deadlock memory reclaim. THis
occurs when memory reclaim (such as run by kswapd) is reclaiming XFS
inodes and issues a log force to unpin inodes that are dirty in the
CIL.
The CIL is pushed, but this will only occur once it gets the CIL
context lock to ensure that all committing transactions are complete
and no new transactions start being committed to the CIL while the
push switches to a new context.
The deadlock occurs when the CIL context lock is held by a
committing process that is doing memory allocation for log vector
buffers, and that allocation is then blocked on memory reclaim
making progress. Memory reclaim, however, is blocked waiting for
a log force to make progress, and so we effectively deadlock at this
point.
To solve this problem, we have to move the CIL log vector buffer
allocation outside of the context lock so that memory reclaim can
always make progress when it needs to force the log. The problem
with doing this is that a CIL push can take place while we are
determining if we need to allocate a new log vector buffer for
an item and hence the current log vector may go away without
warning. That means we canot rely on the existing log vector being
present when we finally grab the context lock and so we must have a
replacement buffer ready to go at all times.
To ensure this, introduce a "shadow log vector" buffer that is
always guaranteed to be present when we gain the CIL context lock
and format the item. This shadow buffer may or may not be used
during the formatting, but if the log item does not have an existing
log vector buffer or that buffer is too small for the new
modifications, we swap it for the new shadow buffer and format
the modifications into that new log vector buffer.
The result of this is that for any object we modify more than once
in a given CIL checkpoint, we double the memory required
to track dirty regions in the log. For single modifications then
we consume the shadow log vectorwe allocate on commit, and that gets
consumed by the checkpoint. However, if we make multiple
modifications, then the second transaction commit will allocate a
shadow log vector and hence we will end up with double the memory
usage as only one of the log vectors is consumed by the CIL
checkpoint. The remaining shadow vector will be freed when th elog
item is freed.
This can probably be optimised in future - access to the shadow log
vector is serialised by the object lock (as opposited to the active
log vector, which is controlled by the CIL context lock) and so we
can probably free shadow log vector from some objects when the log
item is marked clean on removal from the AIL.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfsprogs source commit 4280e59dcbc4cd8e01585efe788a68eb378048e8
xfs_da3_split() has to handle all three versions of the
directory/attribute btree structure. The attr tree is v1, the dir
tre is v2 or v3. The main difference between the v1 and v2/3 trees
is the way tree nodes are split - in the v1 tree we can require a
double split to occur because the object to be inserted may be
larger than the space made by splitting a leaf. In this case we need
to do a double split - one to split the full leaf, then another to
allocate an empty leaf block in the correct location for the new
entry. This does not happen with dir (v2/v3) formats as the objects
being inserted are always guaranteed to fit into the new space in
the split blocks.
Indeed, for directories they *may* be an extra block on this buffer
pointer. However, it's guaranteed not to be a leaf block (i.e. a
directory data block) - the directory code only ever places hash
index or free space blocks in this pointer (as a cursor of
sorts), and so to use it as a directory data block will immediately
corrupt the directory.
The problem is that the code assumes that there may be extra blocks
that we need to link into the tree once we've split the root, but
this is not true for either dir or attr trees, because the extra
attr block is always consumed by the last node split before we split
the root. Hence the linking in an extra block is always wrong at the
root split level, and this manifests itself in repair as a directory
corruption in a repaired directory, leaving the directory rebuild
incomplete.
This is a dir v2 zero-day bug - it was in the initial dir v2 commit
that was made back in February 1998.
Fix this by ensuring the linking of the blocks after the root split
never tries to make use of the extra blocks that may be held in the
cursor. They are held there for other purposes and should never be
touched by the root splitting code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We check IS_DAX(inode) before calling either xfs_file_dax_read or
xfs_file_dax_write, and this will lead the call being optimized out at
compile time when CONFIG_FS_DAX is disabled.
However, the two functions are marked STATIC, so they become global
symbols when CONFIG_XFS_DEBUG is set, leaving us with two unused global
functions that call into an undefined function and a broken "allmodconfig"
build:
fs/built-in.o: In function `xfs_file_dax_read':
fs/xfs/xfs_file.c:348: undefined reference to `dax_do_io'
fs/built-in.o: In function `xfs_file_dax_write':
fs/xfs/xfs_file.c:758: undefined reference to `dax_do_io'
Marking the two functions 'static noinline' instead of 'STATIC' will let
the compiler drop the symbols when there are no callers but avoid the
implicit inlining.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 16d4d43595 ("xfs: split direct I/O and DAX path")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
XFS has had scattered reports of delalloc blocks present at
->releasepage() time. This results in a warning with a stack trace
similar to the following:
...
Call Trace:
[<ffffffffa23c5b8f>] dump_stack+0x63/0x84
[<ffffffffa20837a7>] warn_slowpath_common+0x97/0xe0
[<ffffffffa208380a>] warn_slowpath_null+0x1a/0x20
[<ffffffffa2326caf>] xfs_vm_releasepage+0x10f/0x140
[<ffffffffa218c680>] ? page_mkclean_one+0xd0/0xd0
[<ffffffffa218d3a0>] ? anon_vma_prepare+0x150/0x150
[<ffffffffa21521c2>] try_to_release_page+0x32/0x50
[<ffffffffa2166b2e>] shrink_active_list+0x3ce/0x3e0
[<ffffffffa21671c7>] shrink_lruvec+0x687/0x7d0
[<ffffffffa21673ec>] shrink_zone+0xdc/0x2c0
[<ffffffffa2168539>] kswapd+0x4f9/0x970
[<ffffffffa2168040>] ? mem_cgroup_shrink_node_zone+0x1a0/0x1a0
[<ffffffffa20a0d99>] kthread+0xc9/0xe0
[<ffffffffa20a0cd0>] ? kthread_stop+0x100/0x100
[<ffffffffa26b404f>] ret_from_fork+0x3f/0x70
[<ffffffffa20a0cd0>] ? kthread_stop+0x100/0x100
This occurs because it is possible for shrink_active_list() to send
pages marked dirty to ->releasepage() when certain buffer_head threshold
conditions are met. shrink_active_list() doesn't check the page dirty
state apparently to handle an old ext3 corner case where in some cases
clean pages would not have the dirty bit cleared, thus it is up to the
filesystem to determine how to handle the page.
XFS currently handles the delalloc case properly, but this behavior
makes the warning spurious. Update the XFS ->releasepage() handler to
explicitly skip dirty pages. Retain the existing delalloc/unwritten
checks so we continue to warn if such buffers exist on clean pages when
they shouldn't.
Diagnosed-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead we always declare struct xfs_dir2_sf_hdr as packed. That's
the expected layout, and while most major architectures do the packing
by default the new structure size and offset checker showed that not
only the ARM old ABI got this wrong, but various minor embedded
architectures did as well.
[Verified that no code change on x86-64 results from this change]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
And use an array of unsigned char values directly to avoid problems
with architectures that pad the size of structures. This also gets
rid of the xfs_dir2_ino4_t and xfs_dir2_ino8_t types, and introduces
new constants for the size of 4 and 8 bytes as well as the size
difference between the two.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Just use an array of two unsigned chars directly to avoid problems
with architectures that pad the size of structures.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
So far the DAX code overloaded the direct I/O code path. There is very little
in common between the two, and untangling them allows to clean up both variants.
As a side effect we also get separate trace points for both I/O types.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We control both the callers and callees of ->direct_IO, so remove the
indirect calls.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
XFS already implement it's own flushing of the pagecache because it
implements proper synchronization for direct I/O reads. This means
calling generic_file_read_iter for direct I/O is rather useless,
as it doesn't do much but updating the atime and iocb position for
us. This also gets rid of the buffered I/O fallback that isn't used
for XFS.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Similar to what we did on the write side a while ago.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
All the three low-level read implementations that we might call already
take care of not overflowing the maximum supported bytes, no need to
duplicate it here.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Now that we have the direct I/O kiocb flag there is no real need to sample
the value inside of XFS, and the invis flag was always just partially used
and isn't worth keeping this infrastructure around for. This also splits
the read tracepoint into buffered vs direct as we've done for writes a long
time ago.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead check the file pointer for the invisble I/O flag directly, and
use the chance to drop redundant arguments from the xfs_ioc_space
prototype.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Newly allocated XFS metadata buffers are added to the LRU once the hold
count is released, which typically occurs after I/O completion. There is
no other mechanism at current that tracks the existence or I/O state of
a new buffer. Further, readahead I/O tends to be submitted
asynchronously by nature, which means the I/O can remain in flight and
actually complete long after the calling context is gone. This means
that file descriptors or any other holds on the filesystem can be
released, allowing the filesystem to be unmounted while I/O is still in
flight. When I/O completion occurs, core data structures may have been
freed, causing completion to run into invalid memory accesses and likely
to panic.
This problem is reproduced on XFS via directory readahead. A filesystem
is mounted, a directory is opened/closed and the filesystem immediately
unmounted. The open/close cycle triggers a directory readahead that if
delayed long enough, runs buffer I/O completion after the unmount has
completed.
To address this problem, add a mechanism to track all in-flight,
asynchronous buffers using per-cpu counters in the buftarg. The buffer
is accounted on the first I/O submission after the current reference is
acquired and unaccounted once the buffer is returned to the LRU or
freed. Update xfs_wait_buftarg() to wait on all in-flight I/O before
walking the LRU list. Once in-flight I/O has completed and the workqueue
has drained, all new buffers should have been released onto the LRU.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The upcoming buftarg I/O accounting mechanism maintains a count of
all buffers that have undergone I/O in the current hold-release
cycle. Certain buffers associated with core infrastructure (e.g.,
the xfs_mount superblock buffer, log buffers) are never released,
however. This means that accounting I/O submission on such buffers
elevates the buftarg count indefinitely and could lead to lockup on
unmount.
Define a new buffer flag to explicitly exclude buffers from buftarg
I/O accounting. Set the flag on the superblock and associated log
buffers.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
With the code as it stands today, b_retries never increments because
it gets reset to 0 in the error callback.
Remove that, and fix a similar problem where the first retry time
was constantly being overwritten, which defeated the timeout tunable
as well. We now only set first retry time if a non-zero timeout is
set, to match the behavior of only incrementing retries if a retry
value is set.
This way max retries & timeouts consistently take effect after a
tunable is set, rather than acting retroactively on a buffer which
has failed at some point in the past and has accumulated state from
those prior failures.
Thanks to dchinner for talking through this with me.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Fix up a couple places where extra flag manipulation occurs.
In the first case we clear XBF_ASYNC and then immediately reset it -
so don't bother clearing in the first place.
In the 2nd case we are at a point in the function where the buffer
must already be async, so there is no need to reset it.
Add consistent spacing around the " | " while we're at it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_error_get_cfg() is called with bp->b_error as an arg, which is
negative, so the switch statement won't ever find any matches.
This results in only the default error handler having any effect, as
EIO/ENOSPC/ENODEV get ignored due to the wrong sign.
It seems simplest to always flip the error sign to positive, so that
we can handle either negative errors in bp->b_error, or possibly a
positive errno via something like xfs_error_get_cfg(EIO) - this
future-proofs the function.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
replace the magic numbers by offsetof(...) and sizeof(...), and add two
extra checks on xfs_check_ondisk_structs()
[dchinner: renamed header structures to be more descriptive]
Signed-off-by: Hou Tao <houtao1@huawei.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The indentation in this function is different from the other functions.
Those spacebars are converted to tabs to improve readability.
Signed-off-by: Kaho Ng <ngkaho1234@gmail.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Errors go from zero which means no error to XFS_ERRTAG_MAX (22). My
static checker complains that xfs_errortag_add() puts an upper bound on
this but not a lower bound. Let's fix it by making it unsigned.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When calling fdget() in xfs_ioc_swapext(), we need to verify that
the file descriptors passed into the ioctl point to XFS inodes
before we start operations on them. If we don't do this, we could be
referencing arbitrary kernel memory as an XFS inode. THis could lead
to memory corruption and/or performing locking operations on
attacker-chosen structures in kernel memory.
[dchinner: rewrite commit message ]
[dchinner: add comment explaining new check ]
Signed-off-by: Jann Horn <jann@thejh.net>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Without this check, the following XFS_I invocations would return bad
pointers when used on non-XFS inodes (perhaps pointers into preceding
allocator chunks).
This could be used by an attacker to trick xfs_swap_extents into
performing locking operations on attacker-chosen structures in kernel
memory, potentially leading to code execution in the kernel. (I have
not investigated how likely this is to be usable for an attack in
practice.)
Signed-off-by: Jann Horn <jann@thejh.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Chinner <david@fromorbit.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Instead of creeping pnfs layout configuration into filesystems, move the
definition of block-based export operations under a more abstract
configuration.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Create a common function to calculate the maximum height of a per-AG
btree. This will eventually be used by the rmapbt and refcountbt
code to calculate appropriate maxlevels values for each. This is
important because the verifiers and the transaction block
reservations depend on accurate estimates of how many blocks are
needed to satisfy a btree split.
We were mistakenly using the max bnobt height for all the btrees,
which creates a dangerous situation since the larger records and
keys in an rmapbt make it very possible that the rmapbt will be
taller than the bnobt and so we can run out of transaction block
reservation.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In struct xfs_bmap_free, convert the open-coded free extent list to
a regular list, then use list_sort to sort it prior to processing.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Break up xfs_free_extent() into a helper that fixes the freelist.
This helper will be used subsequently to ensure the freelist during
deferred rmap processing.
[darrick: refactor to put this at the head of the patchset]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This is already in xfsprogs' libxfs, so port it to the kernel.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently we don't check the error_tag when someone's trying to set up
error injection testing. If userspace passes in a value we don't know
about, send back an error. This will help xfstests to _notrun a test
that uses error injection to test things like log replay.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Create a second buf_trylock tracepoint so that we can distinguish
between a successful and a failed trylock. With this piece, we can
use a script to look at the ftrace output to detect buffer deadlocks.
[dchinner: update to if/else as per hch's suggestion]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Some of the directory/attr structures contain variable-length objects,
so the enclosing structure doesn't have a meaningful fixed size at
compile time. We can check the offsets of the members before the
variable-length member, so do those.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_reserve_blocks() is responsible to update the XFS reserved block
pool count at mount time or based on user request. When the caller
requests to increase the reserve pool, blocks must be allocated from
the global counters such that they are no longer available for
general purpose use. If the requested reserve pool size is too
large, XFS reserves what blocks are available. The implementation
requires looking at the percpu counters and making an educated guess
as to how many blocks to try and allocate from xfs_mod_fdblocks(),
which can return -ENOSPC if the guess was not accurate due to
counters being modified in parallel.
xfs_reserve_blocks() retries the guess in this scenario until the
allocation succeeds or it is determined that there is no space
available in the fs. While not easily reproducible in the current
form, the retry code doesn't actually work correctly if
xfs_mod_fdblocks() actually fails. The problem is that the percpu
calculations use the m_resblks counter to determine how many blocks
to allocate, but unconditionally update m_resblks before the block
allocation has actually succeeded. Therefore, if xfs_mod_fdblocks()
fails, the code jumps to the retry label and uses the already
updated m_resblks value to determine how many blocks to try and
allocate. If the percpu counters previously suggested that the
entire request was available, fdblocks_delta could end up set to 0.
In that case, m_resblks is updated to the requested value, yet no
blocks have been reserved at all.
Refactor xfs_reserve_blocks() to use an explicit loop and make the
code easier to follow. Since we have to drop the spinlock across the
xfs_mod_fdblocks() call, use a delta value for m_resblks as well and
only apply the delta once allocation succeeds.
[dchinner: convert to do {} while() loop]
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The filesystem quiesce sequence performs the operations necessary to
drain all background work, push pending transactions through the log
infrastructure and wait on I/O resulting from the final AIL push. We
have had reports of remount,ro hangs in xfs_log_quiesce() ->
xfs_wait_buftarg(), however, and some instrumentation code to detect
transaction commits at this point in the quiesce sequence has inculpated
the eofblocks background scanner as a cause.
While higher level remount code generally prevents user modifications by
the time the filesystem has made it to xfs_log_quiesce(), the background
scanner may still be alive and can perform pending work at any time. If
this occurs between the xfs_log_force() and xfs_wait_buftarg() calls
within xfs_log_quiesce(), this can lead to an indefinite lockup in
xfs_wait_buftarg().
To prevent this problem, cancel the background eofblocks scan worker
during the remount read-only quiesce sequence. This suspends background
trimming when a filesystem is remounted read-only. This is only done in
the remount path because the freeze codepath has already locked out new
transactions by the time the filesystem attempts to quiesce (and thus
waiting on an active work item could deadlock). Kick the eofblocks
worker to pick up where it left off once an fs is remounted back to
read-write.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Instead punch the whole first, and the use the our zeroing helper
to punch out the edge blocks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We now skip holes in it, so no need to have the caller do it as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We'll want to use this code for large offsets now that we're
skipping holes and unwritten extents efficiently. Also rename it to
xfs_zero_range to be a bit more descriptive, and tell the caller if
we actually did any zeroing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Note that this removes support for the untested FIEMAP_FLAG_XATTR. It
could be added relatively easily with iomap ops for the attr fork, but
without test coverage I don't feel safe doing this.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Convert XFS to use the new iomap based multipage write path. This involves
implementing the ->iomap_begin and ->iomap_end methods, and switching the
buffered file write, page_mkwrite and xfs_iozero paths to the new iomap
helpers.
With this change __xfs_get_blocks will never be used for buffered writes,
and the code handling them can be removed.
Based on earlier code from Dave Chinner.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently zeroing out blocks and waiting for writeout is a bit of a mess in
truncate. This patch gives it a clear order in preparation for the iomap
path:
(1) we first wait for any direct I/O to complete to prevent any races
for it
(2) we then perform the actual zeroing, and only use the truncate_page
helpers for truncating down. The truncate up case already is
handled by the separate call to xfs_zero_eof.
(3) only then we write back dirty data, as zeroing block may cause
dirty pages when using either xfs_zero_eof or the new iomap
infrastructure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
And ensure it works for RT subvolume files an set the block device,
both of which will be needed to be able to use the function in the
buffered write path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
BIO_MAX_PAGES is used as maximum count of bvecs, so
replace BIO_MAX_SECTORS with BIO_MAX_PAGES since
BIO_MAX_SECTORS is to be removed.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Tested-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
To avoid confusion between REQ_OP_FLUSH, which is handled by
request_fn drivers, and upper layers requesting the block layer
perform a flush sequence along with possibly a WRITE, this patch
renames REQ_FLUSH to REQ_PREFLUSH.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Separate the op from the rq_flag_bits and have xfs
set/get the bio using bio_set_op_attrs/bio_op.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw
instead of passing it in. This makes that use the same as
generic_make_request and how we set the other bio fields.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixed up fs/ext4/crypto.c
Signed-off-by: Jens Axboe <axboe@fb.com>
When we have a lot of metadata to flush from the AIL, the buffer
list can get very long. The current submission code tries to batch
submission to optimise IO order of the metadata (i.e. ascending
block order) to maximise block layer merging or IO to adjacent
metadata blocks.
Unfortunately, the method used can result in long lock times
occurring as buffers locked early on in the buffer list might not be
dispatched until the end of the IO licst processing. This is because
sorting does not occur util after the buffer list has been processed
and the buffers that are going to be submitted are locked. Hence
when the buffer list is several thousand buffers long, the lock hold
times before IO dispatch can be significant.
To fix this, sort the buffer list before we start trying to lock and
submit buffers. This means we can now submit buffers immediately
after they are locked, allowing merging to occur immediately on the
plug and dispatch to occur as quickly as possible. This means there
is minimal delay between locking the buffer and IO submission
occuring, hence reducing the worst case lock hold times seen during
delayed write buffer IO submission signficantly.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
And the same for XFS_IOC_THAW. Just because we now have a common
version of the ioctl we still need to provide the old name for it
for anyone using those.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Al Viro noticed that xfs_lock_inodes should be static, and
that led to ... a few more.
These are just the easy ones, others require moving functions
higher in source files, so that's not done here to keep
this review simple.
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The static checker reports that after commit 8d99fe92fe ("xfs: fix
efi/efd error handling to avoid fs shutdown hangs"), the code has been
reworked such that error == -EFSCORRUPTED is not possible in this
codepath.
Remove the spurious error check and just use SHUTDOWN_META_IO_ERROR
unconditionally.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Multi-block buffers are logged based on buffer offset in
xfs_trans_log_buf(). xfs_buf_item_log() ultimately walks each mapping in
the buffer and marks the associated range to be logged in the
xfs_buf_log_format bitmap for that mapping. This code is broken,
however, in that it marks the actual buffer offsets of the associated
range in each bitmap rather than shifting to the byte range for that
particular mapping.
For example, on a 4k fsb fs, buffer offset 4096 refers to the first byte
of the second mapping in the buffer. This means byte 0 of the second log
format bitmap should be tagged as dirty. Instead, the current code marks
byte offset 4096 of the second log format bitmap, which is invalid and
potentially out of range of the mapping.
As a result of this, the log item format code invoked at transaction
commit time is not be able to correctly identify what parts of the
buffer to copy into log vectors. This can lead to NULL log vector
pointer dereferences in CIL push context if the item format code was not
able to locate any dirty ranges at all. This crash has been reproduced
on a 4k FSB filesystem using 16k directory blocks where an unlink
operation happened not to log anything in the first block of the
mapping. The logged offsets were all over 4k, marked as such in the
subsequent log format mappings, and thus left the transaction with an
xfs_log_item that is marked DIRTY but without any logged regions.
Further, even when the logged regions are marked correctly in the buffer
log format bitmaps, the format code doesn't copy the correct ranges of
the buffer into the log. This means that any logged region beyond the
first block of a multi-block buffer is subject to corruption after a
crash and log recovery sequence. This is due to a failure to convert the
mapping bm_len field from basic blocks to bytes in the buffer offset
tracking code in xfs_buf_item_format().
Update xfs_buf_item_log() to convert buffer offsets to segment relative
offsets when logging multi-block buffers. This ensures that the modified
regions of a buffer are logged correctly and avoids the aforementioned
crash. Also update xfs_buf_item_format() to correctly track the source
offset into the buffer for the log vector formatting code. This ensures
that the correct data is copied into the log.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
it's not needed for file_operations of inodes located on fs defined
in the hosting module and for file_operations that go into procfs.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull vfs fixes from Al Viro:
"Followups to the parallel lookup work:
- update docs
- restore killability of the places that used to take ->i_mutex
killably now that we have down_write_killable() merged
- Additionally, it turns out that I missed a prerequisite for
security_d_instantiate() stuff - ->getxattr() wasn't the only thing
that could be called before dentry is attached to inode; with smack
we needed the same treatment applied to ->setxattr() as well"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
switch ->setxattr() to passing dentry and inode separately
switch xattr_handler->set() to passing dentry and inode separately
restore killability of old mutex_lock_killable(&inode->i_mutex) users
add down_write_killable_nested()
update D/f/directory-locking
- Until now, dax has been disabled if media errors were found on
any device. This enables the use of DAX in the presence of these
errors by making all sector-aligned zeroing go through the driver.
- The driver (already) has the ability to clear errors on writes that
are sent through the block layer using 'DSMs' defined in ACPI 6.1.
Other misc changes:
- When mounting DAX filesystems, check to make sure the partition
is page aligned. This is a requirement for DAX, and previously, we
allowed such unaligned mounts to succeed, but subsequent reads/writes
would fail.
- Misc/cleanup fixes from Jan that remove unused code from DAX related to
zeroing, writeback, and some size checks.
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Merge tag 'dax-misc-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull misc DAX updates from Vishal Verma:
"DAX error handling for 4.7
- Until now, dax has been disabled if media errors were found on any
device. This enables the use of DAX in the presence of these
errors by making all sector-aligned zeroing go through the driver.
- The driver (already) has the ability to clear errors on writes that
are sent through the block layer using 'DSMs' defined in ACPI 6.1.
Other misc changes:
- When mounting DAX filesystems, check to make sure the partition is
page aligned. This is a requirement for DAX, and previously, we
allowed such unaligned mounts to succeed, but subsequent
reads/writes would fail.
- Misc/cleanup fixes from Jan that remove unused code from DAX
related to zeroing, writeback, and some size checks"
* tag 'dax-misc-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
dax: fix a comment in dax_zero_page_range and dax_truncate_page
dax: for truncate/hole-punch, do zeroing through the driver if possible
dax: export a low-level __dax_zero_page_range helper
dax: use sb_issue_zerout instead of calling dax_clear_sectors
dax: enable dax in the presence of known media errors (badblocks)
dax: fallback from pmd to pte on error
block: Update blkdev_dax_capable() for consistency
xfs: Add alignment check for DAX mount
ext2: Add alignment check for DAX mount
ext4: Add alignment check for DAX mount
block: Add bdev_dax_supported() for dax mount checks
block: Add vfs_msg() interface
dax: Remove redundant inode size checks
dax: Remove pointless writeback from dax_do_io()
dax: Remove zeroing from dax_io()
dax: Remove dead zeroing code from fault handlers
ext2: Avoid DAX zeroing to corrupt data
ext2: Fix block zeroing in ext2_get_blocks() for DAX
dax: Remove complete_unwritten argument
DAX: move RADIX_DAX_ definitions to dax.c
Changes in this update:
o fixes for mount line parsing, sparse warnings, read-only compat
feature remount behaviour
o allow fast path symlink lookups for inline symlinks.
o attribute listing cleanups
o writeback goes direct to bios rather than indirecting through
bufferheads
o transaction allocation cleanup
o optimised kmem_realloc
o added configurable error handling for metadata write errors,
changed default error handling behaviour from "retry forever" to
"retry until unmount then fail"
o fixed several inode cluster writeback lookup vs reclaim race
conditions
o fixed inode cluster writeback checking wrong inode after lookup
o fixed bugs where struct xfs_inode freeing wasn't actually RCU safe
o cleaned up inode reclaim tagging
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Merge tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs updates from Dave Chinner:
"A pretty average collection of fixes, cleanups and improvements in
this request.
Summary:
- fixes for mount line parsing, sparse warnings, read-only compat
feature remount behaviour
- allow fast path symlink lookups for inline symlinks.
- attribute listing cleanups
- writeback goes direct to bios rather than indirecting through
bufferheads
- transaction allocation cleanup
- optimised kmem_realloc
- added configurable error handling for metadata write errors,
changed default error handling behaviour from "retry forever" to
"retry until unmount then fail"
- fixed several inode cluster writeback lookup vs reclaim race
conditions
- fixed inode cluster writeback checking wrong inode after lookup
- fixed bugs where struct xfs_inode freeing wasn't actually RCU safe
- cleaned up inode reclaim tagging"
* tag 'xfs-for-linus-4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (39 commits)
xfs: fix warning in xfs_finish_page_writeback for non-debug builds
xfs: move reclaim tagging functions
xfs: simplify inode reclaim tagging interfaces
xfs: rename variables in xfs_iflush_cluster for clarity
xfs: xfs_iflush_cluster has range issues
xfs: mark reclaimed inodes invalid earlier
xfs: xfs_inode_free() isn't RCU safe
xfs: optimise xfs_iext_destroy
xfs: skip stale inodes in xfs_iflush_cluster
xfs: fix inode validity check in xfs_iflush_cluster
xfs: xfs_iflush_cluster fails to abort on error
xfs: remove xfs_fs_evict_inode()
xfs: add "fail at unmount" error handling configuration
xfs: add configuration handlers for specific errors
xfs: add configuration of error failure speed
xfs: introduce table-based init for error behaviors
xfs: add configurable error support to metadata buffers
xfs: introduce metadata IO error class
xfs: configurable error behavior via sysfs
xfs: buffer ->bi_end_io function requires irq-safe lock
...
dax_clear_sectors() cannot handle poisoned blocks. These must be
zeroed using the BIO interface instead. Convert ext2 and XFS to use
only sb_issue_zerout().
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
[vishal: Also remove the dax_clear_sectors function entirely]
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Pull parallel lookup fixups from Al Viro:
"Fix for xfs parallel readdir (turns out the cxfs exposure was not
enough to catch all problems), and a reversion of btrfs back to
->iterate() until the fs/btrfs/delayed-inode.c gets fixed"
* 'work.lookups' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
xfs: concurrent readdir hangs on data buffer locks
Revert "btrfs: switch to ->iterate_shared()"
There's a three-process deadlock involving shared/exclusive barriers
and inverted lock orders in the directory readdir implementation.
It's a pre-existing problem with lock ordering, exposed by the
VFS parallelisation code.
process 1 process 2 process 3
--------- --------- ---------
readdir
iolock(shared)
get_leaf_dents
iterate entries
ilock(shared)
map, lock and read buffer
iunlock(shared)
process entries in buffer
.....
readdir
iolock(shared)
get_leaf_dents
iterate entries
ilock(shared)
map, lock buffer
<blocks>
finish ->iterate_shared
file_accessed()
->update_time
start transaction
ilock(excl)
<blocks>
.....
finishes processing buffer
get next buffer
ilock(shared)
<blocks>
And that's the deadlock.
Fix this by dropping the current buffer lock in process 1 before
trying to map the next buffer. This means we keep the lock order of
ilock -> buffer lock intact and hence will allow process 3 to make
progress and drop it's ilock(shared) once it is done.
Reported-by: Xiong Zhou <xzhou@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Rearrange the inode tagging functions so that they are higher up in
xfs_cache.c and so there is no need for forward prototypes to be
defined. This is purely code movement, no other change.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Inode radix tree tagging for reclaim passes a lot of unnecessary
variables around. Over time the xfs-perag has grown a xfs_mount
backpointer, and an internal agno so we don't need to pass other
variables into the tagging functions to supply this information.
Rework the functions to pass the minimal variable set required
and simplify the internal logic and flow.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The cluster inode variable uses unconventional naming - iq - which
makes it hard to distinguish it between the inode passed into the
function - ip - and that is a vector for mistakes to be made.
Rename all the cluster inode variables to use a more conventional
prefixes to reduce potential future confusion (cilist, cilist_size,
cip).
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_iflush_cluster() does a gang lookup on the radix tree, meaning
it can find inodes beyond the current cluster if there is sparse
cache population. gang lookups return results in ascending index
order, so stop trying to cluster inodes once the first inode outside
the cluster mask is detected.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The last thing we do before using call_rcu() on an xfs_inode to be
freed is mark it as invalid. This means there is a window between
when we know for certain that the inode is going to be freed and
when we do actually mark it as "freed".
This is important in the context of RCU lookups - we can look up the
inode, find that it is valid, and then use it as such not realising
that it is in the final stages of being freed.
As such, mark the inode as being invalid the moment we know it is
going to be reclaimed. This can be done while we still hold the
XFS_ILOCK_EXCL and the flush lock in xfs_inode_reclaim, meaning that
it occurs well before we remove it from the radix tree, and that
the i_flags_lock, the XFS_ILOCK and the inode flush lock all act as
synchronisation points for detecting that an inode is about to go
away.
For defensive purposes, this allows us to add a further check to
xfs_iflush_cluster to ensure we skip inodes that are being freed
after we grab the XFS_ILOCK_SHARED and the flush lock - we know that
if the inode number if valid while we have these locks held we know
that it has not progressed through reclaim to the point where it is
clean and is about to be freed.
[bfoster: fixed __xfs_inode_clear_reclaim() using ip->i_ino after it
had already been zeroed.]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The xfs_inode freed in xfs_inode_free() has multiple allocated
structures attached to it. We free these in xfs_inode_free() before
we mark the inode as invalid, and before we run call_rcu() to queue
the structure for freeing.
Unfortunately, this freeing can race with other accesses that are in
the RCU current grace period that have found the inode in the radix
tree with a valid state. This includes xfs_iflush_cluster(), which
calls xfs_inode_clean(), and that accesses the inode log item on the
xfs_inode.
The log item structure is freed in xfs_inode_free(), so there is the
possibility we can be accessing freed memory in xfs_iflush_cluster()
after validating the xfs_inode structure as being valid for this RCU
context. Hence we can get spuriously incorrect clean state returned
from such checks. This can lead to use thinking the inode is dirty
when it is, in fact, clean, and so incorrectly attaching it to the
buffer for IO and completion processing.
This then leads to use-after-free situations on the xfs_inode itself
if the IO completes after the current RCU grace period expires. The
buffer callbacks will access the xfs_inode and try to do all sorts
of things it shouldn't with freed memory.
IOWs, xfs_iflush_cluster() only works correctly when racing with
inode reclaim if the inode log item is present and correctly stating
the inode is clean. If the inode is being freed, then reclaim has
already made sure the inode is clean, and hence xfs_iflush_cluster
can skip it. However, we are accessing the inode inode under RCU
read lock protection and so also must ensure that all dynamically
allocated memory we reference in this context is not freed until the
RCU grace period expires.
To fix this, move all the potential memory freeing into
xfs_inode_free_callback() so that we are guarantee RCU protected
lookup code will always have the memory structures it needs
available during the RCU grace period that lookup races can occur
in.
Discovered-by: Brain Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When unmounting XFS, we call:
xfs_inode_free => xfs_idestroy_fork => xfs_iext_destroy
This goes over the whole indirection array and calls
xfs_iext_irec_remove for each one of the erps (from the last one to
the first one). As a result, we keep shrinking (reallocating
actually) the indirection array until we shrink out all of its
elements. When we have files with huge numbers of extents, umount
takes 30-80 sec, depending on the amount of files that XFS loaded
and the amount of indirection entries of each file. The unmount
stack looks like:
[<ffffffffc0b6d200>] xfs_iext_realloc_indirect+0x40/0x60 [xfs]
[<ffffffffc0b6cd8e>] xfs_iext_irec_remove+0xee/0xf0 [xfs]
[<ffffffffc0b6cdcd>] xfs_iext_destroy+0x3d/0xb0 [xfs]
[<ffffffffc0b6cef6>] xfs_idestroy_fork+0xb6/0xf0 [xfs]
[<ffffffffc0b87002>] xfs_inode_free+0xb2/0xc0 [xfs]
[<ffffffffc0b87260>] xfs_reclaim_inode+0x250/0x340 [xfs]
[<ffffffffc0b87583>] xfs_reclaim_inodes_ag+0x233/0x370 [xfs]
[<ffffffffc0b8823d>] xfs_reclaim_inodes+0x1d/0x20 [xfs]
[<ffffffffc0b96feb>] xfs_unmountfs+0x7b/0x1a0 [xfs]
[<ffffffffc0b98e4d>] xfs_fs_put_super+0x2d/0x70 [xfs]
[<ffffffff811e9e36>] generic_shutdown_super+0x76/0x100
[<ffffffff811ea207>] kill_block_super+0x27/0x70
[<ffffffff811ea519>] deactivate_locked_super+0x49/0x60
[<ffffffff811eaaee>] deactivate_super+0x4e/0x70
[<ffffffff81207593>] cleanup_mnt+0x43/0x90
[<ffffffff81207632>] __cleanup_mnt+0x12/0x20
[<ffffffff8108f8e7>] task_work_run+0xa7/0xe0
[<ffffffff81014ff7>] do_notify_resume+0x97/0xb0
[<ffffffff81717c6f>] int_signal+0x12/0x17
Further, this reallocation prevents us from freeing the extent list
from a RCU callback as allocation can block. Hence if the extent
list is in indirect format, optimise the freeing of the extent list
to only use kmem_free calls by freeing entire extent buffer pages at
a time, rather than extent by extent.
[dchinner: simplified freeing loop based on Christoph's suggestion]
Signed-off-by: Alex Lyakas <alex@zadarastorage.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We don't write back stale inodes so we should skip them in
xfs_iflush_cluster, too.
cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Some careless idiot(*) wrote crap code in commit 1a3e8f3 ("xfs:
convert inode cache lookups to use RCU locking") back in late 2010,
and so xfs_iflush_cluster checks the wrong inode for whether it is
still valid under RCU protection. Fix it to lock and check the
correct inode.
(*) Careless-idiot: Dave Chinner <dchinner@redhat.com>
cc: <stable@vger.kernel.org> # 3.10.x-
Discovered-by: Brain Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
When a failure due to an inode buffer occurs, the error handling
fails to abort the inode writeback correctly. This can result in the
inode being reclaimed whilst still in the AIL, leading to
use-after-free situations as well as filesystems that cannot be
unmounted as the inode log items left in the AIL never get removed.
Fix this by ensuring fatal errors from xfs_imap_to_bp() result in
the inode flush being aborted correctly.
cc: <stable@vger.kernel.org> # 3.10.x-
Reported-by: Shyam Kaushik <shyam@zadarastorage.com>
Diagnosed-by: Shyam Kaushik <shyam@zadarastorage.com>
Tested-by: Shyam Kaushik <shyam@zadarastorage.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Joe Lawrence reported a list_add corruption with 4.6-rc1 when
testing some custom md administration code that made it's own
block device nodes for the md array. The simple test loop of:
for i in {0..100}; do
mknod --mode=0600 $tmp/tmp_node b $MAJOR $MINOR
mdadm --detail --export $tmp/tmp_node > /dev/null
rm -f $tmp/tmp_node
done
Would produce this warning in bd_acquire() when mdadm opened the
device node:
list_add double add: new=ffff88043831c7b8, prev=ffff8804380287d8, next=ffff88043831c7b8.
And then produce this from bd_forget from kdevtmpfs evicting a block
dev inode:
list_del corruption. prev->next should be ffff8800bb83eb10, but was ffff88043831c7b8
This is a regression caused by commit c19b3b05 ("xfs: mode di_mode
to vfs inode"). The issue is that xfs_inactive() frees the
unlinked inode, and the above commit meant that this freeing zeroed
the mode in the struct inode. The problem is that after evict() has
called ->evict_inode, it expects the i_mode to be intact so that it
can call bd_forget() or cd_forget() to drop the reference to the
block device inode attached to the XFS inode.
In reality, the only thing we do in xfs_fs_evict_inode() that is not
generic is call xfs_inactive(). We can move the xfs_inactive() call
to xfs_fs_destroy_inode() without any problems at all, and this
will leave the VFS inode intact until it is completely done with it.
So, remove xfs_fs_evict_inode(), and do the work it used to do in
->destroy_inode instead.
cc: <stable@vger.kernel.org> # 4.6
Reported-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
If we take "retry forever" literally on metadata IO errors, we can
hang at unmount, once it retries those writes forever. This is the
default behavior, unfortunately.
Add an error configuration option for this behavior and default it
to "fail" so that an unmount will trigger actuall errors, a shutdown
and allow the unmount to succeed. It will be noisy, though, as it
will log the errors and shutdown that occurs.
To fix this, we need to mark the filesystem as being in the process
of unmounting. Do this with a mount flag that is added at the
appropriate time (i.e. before the blocking AIL sync). We also need
to add this flag if mount fails after the initial phase of log
recovery has been run.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
now most of the infrastructure is in place, we can start adding
support for configuring specific errors such as ENODEV, ENOSPC, EIO,
etc. Add these error configurations and configure them all to have
appropriate behaviours. That is, all will be configured to retry
forever by default, except for ENODEV, which is an unrecoverable
error, so it will be configured to not retry on error
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
On reception of an error, we can fail immediately, perform some
bound amount of retries or retry indefinitely. The current behaviour
we have is to retry forever.
However, we'd like the ability to choose how long the filesystem
should try after an error, it can either fail immediately, retry a
few times, or retry forever. This is implemented by using
max_retries sysfs attribute, to hold the amount of times we allow
the filesystem to retry after an error. Being -1 a special case
where the filesystem will retry indefinitely.
Add both a maximum retry count and a retry timeout so that we can
bound by time and/or physical IO attempts.
Finally, plumb these into xfs_buf_iodone error processing so that
the error behaviour follows the selected configuration.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Before we start expanding the number of error classes and errors we
can configure behaviour for, we need a simple and clear way to
define the default behaviour that we initialized each mount with.
Introduce a table based method for keeping the initial configuration
in, and apply that to the existing initialization code.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
With the error configuration handle for async metadata write errors
in place, we can now add initial support to the IO error processing
in xfs_buf_iodone_error().
Add an infrastructure function to look up the configuration handle,
and rearrange the error handling to prepare the way for different
error handling conigurations to be used.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Now we have the basic infrastructure, add the first error class so
we can build up the infrastructure in a meaningful way. Add the
metadata async write IO error class and sysfs entry, and introduce a
default configuration that matches the existing "retry forever"
behavior for async write metadata buffers.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
We need to be able to change the way XFS behaviours in error
conditions depending on the type of underlying storage. This is
necessary for handling non-traditional block devices with extended
error cases, such as thin provisioned devices that can return ENOSPC
as an IO error.
Introduce the basic sysfs infrastructure needed to define and
configure error behaviours. This is done to be generic enough to
extend to configuring behaviour in other error conditions, such as
ENOMEM, which also has different desired behaviours according to
machine configuration.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reports have surfaced of a lockdep splat complaining about an
irq-safe -> irq-unsafe locking order in the xfs_buf_bio_end_io() bio
completion handler. This only occurs when I/O errors are present
because bp->b_lock is only acquired in this context to protect
setting an error on the buffer. The problem is that this lock can be
acquired with the (request_queue) q->queue_lock held. See
scsi_end_request() or ata_qc_schedule_eh(), for example.
Replace the locked test/set of b_io_error with a cmpxchg() call.
This eliminates the need for the lock and thus the lock ordering
problem goes away.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Pull vfs cleanups from Al Viro:
"More cleanups from Christoph"
* 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
nfsd: use RWF_SYNC
fs: add RWF_DSYNC aand RWF_SYNC
ceph: use generic_write_sync
fs: simplify the generic_write_sync prototype
fs: add IOCB_SYNC and IOCB_DSYNC
direct-io: remove the offset argument to dio_complete
direct-io: eliminate the offset argument to ->direct_IO
xfs: eliminate the pos variable in xfs_file_dio_aio_write
filemap: remove the pos argument to generic_file_direct_write
filemap: remove pos variables in generic_file_read_iter
When a partition is not aligned by 4KB, mount -o dax succeeds,
but any read/write access to the filesystem fails, except for
metadata update.
Call bdev_dax_supported() to perform proper precondition checks
which includes this partition alignment check.
Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Fault handlers currently take complete_unwritten argument to convert
unwritten extents after PTEs are updated. However no filesystem uses
this anymore as the code is racy. Remove the unused argument.
Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
no changes needed (XFS isn't simple, but it has the same parallelism
in the interesting parts exercised from CXFS).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The kiocb already has the new position, so use that. The only interesting
case is AIO, where we currently don't bother updating ki_pos. We're about
to free the kiocb after we're done, so we might as well update it to make
everyone's life simpler.
While we're at it also return the bytes written argument passed in if
we were successful so that the boilerplate error switch code in the
callers can go away.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This will allow us to do per-I/O sync file writes, as required by a lot
of fileservers or storage targets.
XXX: Will need a few additional audits for O_DSYNC
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Including blkdev_direct_IO and dax_do_io. It has to be ki_pos to actually
work, so eliminate the superflous argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
These three warnings are fixed:
fs/xfs/xfs_inode.c:1033:44: warning: Using plain integer as NULL pointer
fs/xfs/xfs_inode_item.c:525:20: warning: context imbalance in 'xfs_inode_item_push' - unexpected unlock
fs/xfs/xfs_dquot.c:696:1: warning: symbol 'xfs_dq_get_next_id' was not declared. Should it be static?
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Use krealloc to implement our realloc function. This helps to avoid
new allocations if we are still in the slab bucket. At least for the
bmap btree root that's actually the common case.
This also allows removing the now unused oldsize argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
I had sent this patch yesterday, but for some reason it didn't reach
xfs list, sending again.
Output the caller of xfs_log_force might be useful when tracing log
checkpoint problems without the need to build kernel with DEBUG.
Signed-off-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
These aren't used for CIL-style logging and can be dropped.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Merge xfs_trans_reserve and xfs_trans_alloc into a single function call
that returns a transaction with all the required log and block reservations,
and which allows passing transaction flags directly to avoid the cumbersome
_xfs_trans_alloc interface.
While we're at it we also get rid of the transaction type argument that has
been superflous since we stopped supporting the non-CIL logging mode. The
guts of it will be removed in another patch.
[dchinner: fixed transaction leak in error path in xfs_setattr_nonsize]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
This patch implements two closely related changes: First it embeds
a bio the ioend structure so that we don't have to allocate one
separately. Second it uses the block layer bio chaining mechanism
to chain additional bios off this first one if needed instead of
manually accounting for multiple bio completions in the ioend
structure. Together this removes a memory allocation per ioend and
greatly simplifies the ioend setup and I/O completion path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Completion of an ioend requires us to walk the bufferhead list to
end writback on all the bufferheads. This, in turn, is needed so
that we can end writeback on all the pages we just did IO on.
To remove our dependency on bufferheads in writeback, we need to
turn this around the other way - we need to walk the pages we've
just completed IO on, and then walk the buffers attached to the
pages and complete their IO. In doing this, we remove the
requirement for the ioend to track bufferheads directly.
To enable IO completion to walk all the pages we've submitted IO on,
we need to keep the bios that we used for IO around until the ioend
has been completed. We can do this simply by chaining the bios to
the ioend at completion time, and then walking their pages directly
just before destroying the ioend.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[hch: changed the xfs_finish_page_writeback calling convention]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Currently adding a buffer to the ioend and then building a bio from
the buffer list are two separate operations. We don't build the bios
and submit them until the ioend is submitted, and this places a
fixed dependency on bufferhead chaining in the ioend.
The first step to removing the bufferhead chaining in the ioend is
on the IO submission side. We can build the bio directly as we add
the buffers to the ioend chain, thereby removing the need for a
latter "buffer-to-bio" submission loop. This allows us to submit
bios on large ioends as soon as we cannot add more data to the bio.
These bios then get captured by the active plug, and hence will be
dispatched as soon as either the plug overflows or we schedule away
from the writeback context. This will reduce submission latency for
large IOs, but will also allow more timely request queue based
writeback blocking when the device becomes congested.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[hch: various small updates]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Consolidate the 2 calls to ->put_listent in
xfs_attr3_leaf_list_int(), by setting up name, namelen, and
valuelen for the local vs remote cases, then call ->put_listent
and do the error handling all in one spot.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
The put_value context member is never set; remove it
and the conditional test in xfs_attr3_leaf_list_int().
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The value is not used; only names and value lengths are
returned. Remove the argument.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Today, the put_listent formatters return either 1 or 0; if
they return 1, some callers treat this as an error and return
it up the stack, despite "1" not being a valid (negative)
error code.
The intent seems to be that if the input buffer is full,
we set seen_enough or set count = -1, and return 1;
but some callers check the return before checking the
seen_enough or count fields of the context.
Fix this by only returning non-zero for actual errors
encountered, and rely on the caller to first check the
return value, then check the values in the context to
decide what to do.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
By overallocating the in-core inode fork data buffer and zero
terminating the link target in xfs_init_local_fork we can avoid
the memory allocation in ->follow_link.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Also drop the now unused readlink_copy export.
[dchinner: use d_inode(dentry) rather than dentry->d_inode]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
In the next patch we'll set up different inode operations for inline vs
out of line symlinks, for that we need to make sure the flags are already
set up properly.
[dchinner: added xfs_setup_iops() call to xfs_rename_alloc_whiteout()]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Commit 2e74af0e11 ("xfs: convert mount option parsing to tokens")
missed a 'break;' in xfs_parseargs() which causes mount to fail with
"-o pqnoenforce" option when mounting a v4 filesystem. xfs/050
catches this failure:
XFS (vda6): Super block does not support project and group quota together
Fixes: 2e74af0e11 ("xfs: convert mount option parsing to tokens")
Signed-off-by: Eryu Guan <guaneryu@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Commit 96f859d ("libxfs: pack the agfl header structure so
XFS_AGFL_SIZE is correct") allowed the freelist to use the empty
slot at the end of the freelist on 64 bit systems that was not
being used due to sizeof() rounding up the structure size.
This has caused versions of xfs_repair prior to 4.5.0 (which also
has the fix) to report this as a corruption once the filesystem has
been grown. Older kernels can also have problems (seen from a whacky
container/vm management environment) mounting filesystems grown on a
system with a newer kernel than the vm/container it is deployed on.
To avoid this problem, change the initial free list indexes not to
wrap across the end of the AGFL, hence avoiding the initialisation
of agf_fllast to the last index in the AGFL.
cc: <stable@vger.kernel.org> # 4.4-4.5
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Today, a kernel which refuses to mount a filesystem read-write
due to unknown ro-compat features can still transition to read-write
via the remount path. The old kernel is most likely none the wiser,
because it's unaware of the new feature, and isn't using it. However,
writing to the filesystem may well corrupt metadata related to that
new feature, and moving to a newer kernel which understand the feature
will have problems.
Right now the only ro-compat feature we have is the free inode btree,
which showed up in v3.16. It would be good to push this back to
all the active stable kernels, I think, so that if anyone is using
newer mkfs (which enables the finobt feature) with older kernel
releases, they'll be protected.
Cc: <stable@vger.kernel.org> # 3.10.x-
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Mostly direct substitution with occasional adjustment or removing
outdated comments.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When get_acl() is called for an inode whose ACL is not cached yet, the
get_acl inode operation is called to fetch the ACL from the filesystem.
The inode operation is responsible for updating the cached acl with
set_cached_acl(). This is done without locking at the VFS level, so
another task can call set_cached_acl() or forget_cached_acl() before the
get_acl inode operation gets to calling set_cached_acl(), and then
get_acl's call to set_cached_acl() results in caching an outdate ACL.
Prevent this from happening by setting the cached ACL pointer to a
task-specific sentinel value before calling the get_acl inode operation.
Move the responsibility for updating the cached ACL from the get_acl
inode operations to get_acl(). There, only set the cached ACL if the
sentinel value hasn't changed.
The sentinel values are chosen to have odd values. Likewise, the value
of ACL_NOT_CACHED is odd. In contrast, ACL object pointers always have
an even value (ACLs are aligned in memory). This allows to distinguish
uncached ACLs values from ACL objects.
In addition, switch from guarding inode->i_acl and inode->i_default_acl
upates by the inode->i_lock spinlock to using xchg() and cmpxchg().
Filesystems that do not want ACLs returned from their get_acl inode
operations to be cached must call forget_cached_acl() to prevent the VFS
from doing so.
(Patch written by Al Viro and Andreas Gruenbacher.)
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
pnfs layout type from Christoph Hellwig. The new layout type is a
variant of the block layout which uses SCSI features to offer improved
fencing and device identification.
Note this pull request also includes the client side of SCSI layout,
with Trond's permission.
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Merge tag 'nfsd-4.6-1' of git://linux-nfs.org/~bfields/linux
Pull more nfsd updates from Bruce Fields:
"Apologies for the previous request, which omitted the top 8 commits
from my for-next branch (including the SCSI layout commits). Thanks
to Trond for spotting my error!"
This actually includes the new layout types, so here's that part of
the pull message repeated:
"Support for a new pnfs layout type from Christoph Hellwig. The new
layout type is a variant of the block layout which uses SCSI features
to offer improved fencing and device identification.
Note this pull request also includes the client side of SCSI layout,
with Trond's permission"
* tag 'nfsd-4.6-1' of git://linux-nfs.org/~bfields/linux:
nfsd: use short read as well as i_size to set eof
nfsd: better layoutupdate bounds-checking
nfsd: block and scsi layout drivers need to depend on CONFIG_BLOCK
nfsd: add SCSI layout support
nfsd: move some blocklayout code
nfsd: add a new config option for the block layout driver
nfs/blocklayout: add SCSI layout support
nfs4.h: add SCSI layout definitions
Change summary:
o error propagation for direct IO failures fixes for both XFS and ext4
o new quota interfaces and XFS implementation for iterating all the quota IDs
in the filesystem
o locking fixes for real-time device extent allocation
o reduction of duplicate information in the xfs and vfs inode, saving roughly
100 bytes of memory per cached inode.
o buffer flag cleanup
o rework of the writepage code to use the generic write clustering mechanisms
o several fixes for inode flag based DAX enablement
o rework of remount option parsing
o compile time verification of on-disk format structure sizes
o delayed allocation reservation overrun fixes
o lots of little error handling fixes
o small memory leak fixes
o enable xfsaild freezing again
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Merge tag 'xfs-for-linus-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs
Pull xfs updates from Dave Chinner:
"There's quite a lot in this request, and there's some cross-over with
ext4, dax and quota code due to the nature of the changes being made.
As for the rest of the XFS changes, there are lots of little things
all over the place, which add up to a lot of changes in the end.
The major changes are that we've reduced the size of the struct
xfs_inode by ~100 bytes (gives an inode cache footprint reduction of
>10%), the writepage code now only does a single set of mapping tree
lockups so uses less CPU, delayed allocation reservations won't
overrun under random write loads anymore, and we added compile time
verification for on-disk structure sizes so we find out when a commit
or platform/compiler change breaks the on disk structure as early as
possible.
Change summary:
- error propagation for direct IO failures fixes for both XFS and
ext4
- new quota interfaces and XFS implementation for iterating all the
quota IDs in the filesystem
- locking fixes for real-time device extent allocation
- reduction of duplicate information in the xfs and vfs inode, saving
roughly 100 bytes of memory per cached inode.
- buffer flag cleanup
- rework of the writepage code to use the generic write clustering
mechanisms
- several fixes for inode flag based DAX enablement
- rework of remount option parsing
- compile time verification of on-disk format structure sizes
- delayed allocation reservation overrun fixes
- lots of little error handling fixes
- small memory leak fixes
- enable xfsaild freezing again"
* tag 'xfs-for-linus-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (66 commits)
xfs: always set rvalp in xfs_dir2_node_trim_free
xfs: ensure committed is initialized in xfs_trans_roll
xfs: borrow indirect blocks from freed extent when available
xfs: refactor delalloc indlen reservation split into helper
xfs: update freeblocks counter after extent deletion
xfs: debug mode forced buffered write failure
xfs: remove impossible condition
xfs: check sizes of XFS on-disk structures at compile time
xfs: ioends require logically contiguous file offsets
xfs: use named array initializers for log item dumping
xfs: fix computation of inode btree maxlevels
xfs: reinitialise per-AG structures if geometry changes during recovery
xfs: remove xfs_trans_get_block_res
xfs: fix up inode32/64 (re)mount handling
xfs: fix format specifier , should be %llx and not %llu
xfs: sanitize remount options
xfs: convert mount option parsing to tokens
xfs: fix two memory leaks in xfs_attr_list.c error paths
xfs: XFS_DIFLAG2_DAX limited by PAGE_SIZE
xfs: dynamically switch modes when XFS_DIFLAG2_DAX is set/cleared
...
This is a simple extension to the block layout driver to use SCSI
persistent reservations for access control and fencing, as well as
SCSI VPD pages for device identification.
For this we need to pass the nfs4_client to the proc_getdeviceinfo method
to generate the reservation key, and add a new fence_client method
to allow for fence actions in the layout driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Split the config symbols into a generic pNFS one, which is invisible
and gets selected by the layout drivers, and one for the block layout
driver.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that migration doesn't clear page->mem_cgroup of live pages anymore,
it's safe to make lock_page_memcg() and the memcg stat functions take
pages, and spare the callers from memcg objects.
[akpm@linux-foundation.org: fix warnings]
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
These patches tag the page cache radix tree eviction entries with the
memcg an evicted page belonged to, thus making per-cgroup LRU reclaim
work properly and be as adaptive to new cache workingsets as global
reclaim already is.
This should have been part of the original thrash detection patch
series, but was deferred due to the complexity of those patches.
This patch (of 5):
So far the only sites that needed to exclude charge migration to
stabilize page->mem_cgroup have been per-cgroup page statistics, hence
the name mem_cgroup_begin_page_stat(). But per-cgroup thrash detection
will add another site that needs to ensure page->mem_cgroup lifetime.
Rename these locking functions to the more generic lock_page_memcg() and
unlock_page_memcg(). Since charge migration is a cgroup1 feature only,
we might be able to delete it at some point, and these now easy to
identify locking sites along with it.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
xfs_dir2_node_trim_free can return with setting the rvalp argument
pointer. Initialize it to 0 at the beginning of the function and
only update it to 1 if we succeeded trimming a freespace block.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
__xfs_trans_roll() can return without setting the
*committed argument; this was a problem for xfs_bmap_finish():
int committed;/* xact committed or not */
...
error = __xfs_trans_roll(tp, ip, &committed);
if (error) {
...
if (committed) {
and we tested an uninitialized "committed" variable on the
error path. No caller is preserving "committed" state across
calls to __xfs_trans_roll(), so just initialize committed inside
the function to avoid future errors like this.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_bmap_del_extent() handles extent removal from the in-core and
on-disk extent lists. When removing a delalloc range, it updates the
indirect block reservation appropriately based on the removal. It
currently enforces that the new indirect block reservation is less than
or equal to the original. This is normally the case in all situations
except for in certain cases when the removed range creates a hole in a
single delalloc extent, thus splitting a single delalloc extent in two.
It is possible with small enough extents to split an indlen==1 extent
into two such slightly smaller extents. This leaves one extent with 0
indirect blocks and leads to assert failures in other areas (e.g.,
xfs_bunmapi() if the extent happens to be removed).
Update the indlen distribution code to steal blocks from the deleted
extent, if necessary, to satisfy the worst case total indirect
reservation for the new extents. This is safe as the caller does not
update the fdblocks counters until the extent is removed. Blocks stolen
in this manner simply remain accounted as allocated, having ownership
transferred from the data extent to an indirect reservation.
As a precaution, fall back to the original reservation algorithm if the
new indlen requirement is not met and warn if we end up with extents
without any reservation at all to detect this more easily in the future.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
The delayed allocation indirect reservation splitting code is not
sufficient in some cases where a delalloc extent is split in two. In
preparation for enhancements to this code, refactor the current indlen
distribution algorithm into a new helper function.
[dchinner: rename temp, temp2 variables]
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
xfs_bunmapi() currently updates the fdblocks counter, unreserves quota,
etc. before the extent is deleted by xfs_bmap_del_extent(). The function
has problems dividing up the indirect reserved blocks for scenarios
where a single delalloc extent is split in two. Particularly, there
aren't always enough blocks reserved for multiple extents in a single
extent reservation.
The solution to this problem is to allow the extent removal code to
steal from the deleted extent to meet indirect reservation requirements.
Move the block of code in xfs_bmapi() that updates the fdblocks counter
to after the call to xfs_bmap_del_extent() to allow the codepath to
update the extent record before the free blocks are accounted. Also,
reshuffle the code slightly so the delalloc accounting occurs near the
xfs_bmap_del_extent() call to provide context for the comments.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Add a DEBUG mode-only sysfs knob to enable forced buffered write
failure. An additional side effect of this mode is brute force killing
of delayed allocation blocks in the range of the write. The latter is
the prime motiviation behind this patch, as userspace test
infrastructure requires a reliable mechanism to create and split
delalloc extents without causing extent conversion.
Certain fallocate operations (i.e., zero range) were used for this in
the past, but the implementations have changed such that delalloc
extents are flushed and converted to real blocks, rendering the test
useless.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
Miklos Szeredi