Commit Graph

341 Commits

Author SHA1 Message Date
Darrick J. Wong
06b1132120 xfs: remove inode log format typedef
Remove xfs_inode_log_format_t now that xfs_inode_log_format is
explicitly padded and therefore is a real on-disk structure.  This
enables xfs/122 to check the size of the structure.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
2017-11-01 15:03:16 -07:00
Brian Foster
9f2a450580 xfs: fix log block underflow during recovery cycle verification
It is possible for mkfs to format very small filesystems with too
small of an internal log with respect to the various minimum size
and block count requirements. If this occurs when the log happens to
be smaller than the scan window used for cycle verification and the
scan wraps the end of the log, the start_blk calculation in
xlog_find_head() underflows and leads to an attempt to scan an
invalid range of log blocks. This results in log recovery failure
and a failed mount.

Since there may be filesystems out in the wild with this kind of
geometry, we cannot simply refuse to mount. Instead, cap the scan
window for cycle verification to the size of the physical log. This
ensures that the cycle verification proceeds as expected when the
scan wraps the end of the log.

Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-26 15:38:29 -07:00
Brian Foster
99c265950b xfs: more robust recovery xlog buffer validation
mkfs has a historical problem where it can format very small
filesystems with too small of a physical log. Under certain
conditions, log recovery of an associated filesystem can end up
passing garbage parameter values to some of the cycle and log record
verification functions due to bugs in log recovery not dealing with
such filesystems properly. This results in attempts to read from
bogus/underflowed log block addresses.

Since the buffer read may ultimately succeed, log recovery can
proceed with bogus data and otherwise go off the rails and crash.
One example of this is a negative last_blk being passed to
xlog_find_verify_log_record() causing us to skip the loop, pass a
NULL head pointer to xlog_header_check_mount() and crash.

Improve the xlog buffer verification to address this problem. We
already verify xlog buffer length, so update this mechanism to also
sanity check for a valid log relative block address and otherwise
return an error. Pass a fixed, valid log block address from
xlog_get_bp() since the target address will be validated when the
buffer is read. This ensures that any bogus log block address/length
calculations lead to graceful mount failure rather than risking a
crash or worse if recovery proceeds with bogus data.

Reported-by: Zorro Lang <zlang@redhat.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-26 15:38:29 -07:00
Christoph Hellwig
42b67dc6ff xfs: remove the never fully implemented UUID fork format
Remove the dead code dealing with the UUID fork format that was never
implemented in Linux (and neither in IRIX as far as I know).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-26 15:38:27 -07:00
Darrick J. Wong
7bf7a193a9 xfs: fix compiler warnings
Fix up all the compiler warnings that have crept in.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-09-02 08:22:19 -07:00
Brian Foster
e67d3d4246 xfs: add log recovery tracepoint for head/tail
Torn write detection and tail overwrite detection can shift the log
head and tail respectively in the event of CRC mismatch or
corruption errors. Add a high-level log recovery tracepoint to dump
the final log head/tail and make those values easily attainable in
debug/diagnostic situations.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:24 -07:00
Brian Foster
a4c9b34d6a xfs: handle -EFSCORRUPTED during head/tail verification
Torn write and tail overwrite detection both trigger only on
-EFSBADCRC errors. While this is the most likely failure scenario
for each condition, -EFSCORRUPTED is still possible in certain cases
depending on what ends up on disk when a torn write or partial tail
overwrite occurs. For example, an invalid log record h_len can lead
to an -EFSCORRUPTED error when running the log recovery CRC pass.

Therefore, update log head and tail verification to trigger the
associated head/tail fixups in the event of -EFSCORRUPTED errors
along with -EFSBADCRC. Also, -EFSCORRUPTED can currently be returned
from xlog_do_recovery_pass() before rhead_blk is initialized if the
first record encountered happens to be corrupted. This leads to an
incorrect 'first_bad' return value. Initialize rhead_blk earlier in
the function to address that problem as well.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:24 -07:00
Brian Foster
4a4f66eac4 xfs: fix log recovery corruption error due to tail overwrite
If we consider the case where the tail (T) of the log is pinned long
enough for the head (H) to push and block behind the tail, we can
end up blocked in the following state without enough free space (f)
in the log to satisfy a transaction reservation:

	0	phys. log	N
	[-------HffT---H'--T'---]

The last good record in the log (before H) refers to T. The tail
eventually pushes forward (T') leaving more free space in the log
for writes to H. At this point, suppose space frees up in the log
for the maximum of 8 in-core log buffers to start flushing out to
the log. If this pushes the head from H to H', these next writes
overwrite the previous tail T. This is safe because the items logged
from T to T' have been written back and removed from the AIL.

If the next log writes (H -> H') happen to fail and result in
partial records in the log, the filesystem shuts down having
overwritten T with invalid data. Log recovery correctly locates H on
the subsequent mount, but H still refers to the now corrupted tail
T. This results in log corruption errors and recovery failure.

Since the tail overwrite results from otherwise correct runtime
behavior, it is up to log recovery to try and deal with this
situation. Update log recovery tail verification to run a CRC pass
from the first record past the tail to the head. This facilitates
error detection at T and moves the recovery tail to the first good
record past H' (similar to truncating the head on torn write
detection). If corruption is detected beyond the range possibly
affected by the max number of iclogs, the log is legitimately
corrupted and log recovery failure is expected.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:23 -07:00
Brian Foster
5297ac1f6d xfs: always verify the log tail during recovery
Log tail verification currently only occurs when torn writes are
detected at the head of the log. This was introduced because a
change in the head block due to torn writes can lead to a change in
the tail block (each log record header references the current tail)
and the tail block should be verified before log recovery proceeds.

Tail corruption is possible outside of torn write scenarios,
however. For example, partial log writes can be detected and cleared
during the initial head/tail block discovery process. If the partial
write coincides with a tail overwrite, the log tail is corrupted and
recovery fails.

To facilitate correct handling of log tail overwites, update log
recovery to always perform tail verification. This is necessary to
detect potential tail overwrite conditions when torn writes may not
have occurred. This changes normal (i.e., no torn writes) recovery
behavior slightly to detect and return CRC related errors near the
tail before actual recovery starts.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:23 -07:00
Brian Foster
284f1c2c9b xfs: fix recovery failure when log record header wraps log end
The high-level log recovery algorithm consists of two loops that
walk the physical log and process log records from the tail to the
head. The first loop handles the case where the tail is beyond the
head and processes records up to the end of the physical log. The
subsequent loop processes records from the beginning of the physical
log to the head.

Because log records can wrap around the end of the physical log, the
first loop mentioned above must handle this case appropriately.
Records are processed from in-core buffers, which means that this
algorithm must split the reads of such records into two partial
I/Os: 1.) from the beginning of the record to the end of the log and
2.) from the beginning of the log to the end of the record. This is
further complicated by the fact that the log record header and log
record data are read into independent buffers.

The current handling of each buffer correctly splits the reads when
either the header or data starts before the end of the log and wraps
around the end. The data read does not correctly handle the case
where the prior header read wrapped or ends on the physical log end
boundary. blk_no is incremented to or beyond the log end after the
header read to point to the record data, but the split data read
logic triggers, attempts to read from an invalid log block and
ultimately causes log recovery to fail. This can be reproduced
fairly reliably via xfstests tests generic/047 and generic/388 with
large iclog sizes (256k) and small (10M) logs.

If the record header read has pushed beyond the end of the physical
log, the subsequent data read is actually contiguous. Update the
data read logic to detect the case where blk_no has wrapped, mod it
against the log size to read from the correct address and issue one
contiguous read for the log data buffer. The log record is processed
as normal from the buffer(s), the loop exits after the current
iteration and the subsequent loop picks up with the first new record
after the start of the log.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:23 -07:00
Linus Torvalds
642338ba33 Changes for 4.13:
- Avoid quotacheck deadlocks
 - Fix transaction overflows when bunmapping fragmented files
 - Refactor directory readahead
 - Allow admin to configure if ASSERT is fatal
 - Improve transaction usage detail logging during overflows
 - Minor cleanups
 - Don't leak log items when the log shuts down
 - Remove double-underscore typedefs
 - Various preparation for online scrubbing
 - Introduce new error injection configuration sysfs knobs
 - Refactor dq_get_next to use extent map directly
 - Fix problems with iterating the page cache for unwritten data
 - Implement SEEK_{HOLE,DATA} via iomap
 - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA
 - Don't use MAXPATHLEN to check on-disk symlink target lengths
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Merge tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull XFS updates from Darrick Wong:
 "Here are some changes for you for 4.13. For the most part it's fixes
  for bugs and deadlock problems, and preparation for online fsck in
  some future merge window.

   - Avoid quotacheck deadlocks

   - Fix transaction overflows when bunmapping fragmented files

   - Refactor directory readahead

   - Allow admin to configure if ASSERT is fatal

   - Improve transaction usage detail logging during overflows

   - Minor cleanups

   - Don't leak log items when the log shuts down

   - Remove double-underscore typedefs

   - Various preparation for online scrubbing

   - Introduce new error injection configuration sysfs knobs

   - Refactor dq_get_next to use extent map directly

   - Fix problems with iterating the page cache for unwritten data

   - Implement SEEK_{HOLE,DATA} via iomap

   - Refactor XFS to use iomap SEEK_HOLE and SEEK_DATA

   - Don't use MAXPATHLEN to check on-disk symlink target lengths"

* tag 'xfs-4.13-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (48 commits)
  xfs: don't crash on unexpected holes in dir/attr btrees
  xfs: rename MAXPATHLEN to XFS_SYMLINK_MAXLEN
  xfs: fix contiguous dquot chunk iteration livelock
  xfs: Switch to iomap for SEEK_HOLE / SEEK_DATA
  vfs: Add iomap_seek_hole and iomap_seek_data helpers
  vfs: Add page_cache_seek_hole_data helper
  xfs: remove a whitespace-only line from xfs_fs_get_nextdqblk
  xfs: rewrite xfs_dq_get_next_id using xfs_iext_lookup_extent
  xfs: Check for m_errortag initialization in xfs_errortag_test
  xfs: grab dquots without taking the ilock
  xfs: fix semicolon.cocci warnings
  xfs: Don't clear SGID when inheriting ACLs
  xfs: free cowblocks and retry on buffered write ENOSPC
  xfs: replace log_badcrc_factor knob with error injection tag
  xfs: convert drop_writes to use the errortag mechanism
  xfs: remove unneeded parameter from XFS_TEST_ERROR
  xfs: expose errortag knobs via sysfs
  xfs: make errortag a per-mountpoint structure
  xfs: free uncommitted transactions during log recovery
  xfs: don't allow bmap on rt files
  ...
2017-07-10 10:51:53 -07:00
Brian Foster
39775431f8 xfs: free uncommitted transactions during log recovery
Log recovery allocates in-core transaction and member item data
structures on-demand as it processes the on-disk log. Transactions
are allocated on first encounter on-disk and stored in a hash table
structure where they are easily accessible for subsequent lookups.
Transaction items are also allocated on demand and are attached to
the associated transactions.

When a commit record is encountered in the log, the transaction is
committed to the fs and the in-core structures are freed. If a
filesystem crashes or shuts down before all in-core log buffers are
flushed to the log, however, not all transactions may have commit
records in the log. As expected, the modifications in such an
incomplete transaction are not replayed to the fs. The in-core data
structures for the partial transaction are never freed, however,
resulting in a memory leak.

Update xlog_do_recovery_pass() to first correctly initialize the
hash table array so empty lists can be distinguished from populated
lists on function exit. Update xlog_recover_free_trans() to always
remove the transaction from the list prior to freeing the associated
memory. Finally, walk the hash table of transaction lists as the
last step before it goes out of scope and free any transactions that
may remain on the lists. This prevents a memory leak of partial
transactions in the log.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-06-24 10:11:41 -07:00
Darrick J. Wong
c8ce540db5 xfs: remove double-underscore integer types
This is a purely mechanical patch that removes the private
__{u,}int{8,16,32,64}_t typedefs in favor of using the system
{u,}int{8,16,32,64}_t typedefs.  This is the sed script used to perform
the transformation and fix the resulting whitespace and indentation
errors:

s/typedef\t__uint8_t/typedef __uint8_t\t/g
s/typedef\t__uint/typedef __uint/g
s/typedef\t__int\([0-9]*\)_t/typedef int\1_t\t/g
s/__uint8_t\t/__uint8_t\t\t/g
s/__uint/uint/g
s/__int\([0-9]*\)_t\t/__int\1_t\t\t/g
s/__int/int/g
/^typedef.*int[0-9]*_t;$/d

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-06-19 14:11:33 -07:00
Amir Goldstein
d905fdaaa7 xfs: use the common helper uuid_is_null()
Use the common helper uuid_is_null() and remove the xfs specific
helper uuid_is_nil().

The common helper does not check for the NULL pointer value as
xfs helper did, but xfs code never calls the helper with a pointer
that can be NULL.

Conform comments and warning strings to use the term 'null uuid'
instead of 'nil uuid', because this is the terminology used by
lib/uuid.c and its users. It is also the terminology used in
userspace by libuuid and xfsprogs.

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
[hch: remove now unused uuid.[ch]]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-06-05 16:59:08 +02:00
Masahiro Yamada
6e7c2b4dd3 scripts/spelling.txt: add "intialise(d)" pattern and fix typo instances
Fix typos and add the following to the scripts/spelling.txt:

  intialisation||initialisation
  intialised||initialised
  intialise||initialise

This commit does not intend to change the British spelling itself.

Link: http://lkml.kernel.org/r/1481573103-11329-18-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-05-08 17:15:13 -07:00
Dave Chinner
a444d72e60 Merge branch 'xfs-4.10-misc-fixes-3' into for-next 2016-12-07 17:42:30 +11:00
Dave Chinner
cae028df53 xfs: optimise CRC updates
Nick Piggin reported that the CRC overhead in an fsync heavy
workload was higher than expected on a Power8 machine. Part of this
was to do with the fact that the power8 CRC implementation is not
efficient for CRC lengths of less than 512 bytes, and so the way we
split the CRCs over the CRC field means a lot of the CRCs are
reduced to being less than than optimal size.

To optimise this, change the CRC update mechanism to zero the CRC
field first, and then compute the CRC in one pass over the buffer
and write the result back into the buffer. We can do this safely
because anything writing a CRC has exclusive access to the buffer
the CRC is being calculated over.

We leave the CRC verify code the same - it still splits the CRC
calculation - because we do not want read-only operations modifying
the underlying buffer. This is because read-only operations may not
have an exclusive access to the buffer guaranteed, and so temporary
modifications could leak out to to other processes accessing the
buffer concurrently.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-12-05 14:40:32 +11:00
Eric Sandeen
200237d674 xfs: Move AGI buffer type setting to xfs_read_agi
We've missed properly setting the buffer type for
an AGI transaction in 3 spots now, so just move it
into xfs_read_agi() and set it if we are in a transaction
to avoid the problem in the future.

This is similar to how it is done in i.e. the dir3
and attr3 read functions.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-12-05 12:31:31 +11:00
Eric Sandeen
6b10b23ca9 xfs: set AGI buffer type in xlog_recover_clear_agi_bucket
xlog_recover_clear_agi_bucket didn't set the
type to XFS_BLFT_AGI_BUF, so we got a warning during log
replay (or an ASSERT on a debug build).

    XFS (md0): Unknown buffer type 0!
    XFS (md0): _xfs_buf_ioapply: no ops on block 0xaea8802/0x1

Fix this, as was done in f19b872b for 2 other locations
with the same problem.

cc: <stable@vger.kernel.org> # 3.10 to current
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-12-05 12:31:06 +11:00
Darrick J. Wong
755c7bf5dd libxfs: convert ushort to unsigned short
Since xfsprogs dropped ushort in favor of unsigned short, do that
here too.

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>
2016-11-08 11:55:48 +11:00
Darrick J. Wong
17c12bcd30 xfs: when replaying bmap operations, don't let unlinked inodes get reaped
Log recovery will iget an inode to replay BUI items and iput the inode
when it's done.  Unfortunately, if the inode was unlinked, the iput
will see that i_nlink == 0 and decide to truncate & free the inode,
which prevents us from replaying subsequent BUIs.  We can't skip the
BUIs because we have to replay all the redo items to ensure that
atomic operations complete.

Since unlinked inode recovery will reap the inode anyway, we can
safely introduce a new inode flag to indicate that an inode is in this
'unlinked recovery' state and should not be auto-reaped in the
drop_inode path.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-04 11:05:44 -07:00
Darrick J. Wong
77d61fe45e xfs: log bmap intent items
Provide a mechanism for higher levels to create BUI/BUD items, submit
them to the log, and a stub function to deal with recovered BUI 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: Christoph Hellwig <hch@lst.de>
2016-10-04 11:05:44 -07:00
Darrick J. Wong
a90c00f055 xfs: add refcount btree block detection to log recovery
Identify refcountbt blocks in the log correctly so that we can
validate them during log recovery.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-03 09:11:23 -07:00
Darrick J. Wong
f997ee2137 xfs: log refcount intent items
Provide a mechanism for higher levels to create CUI/CUD items, submit
them to the log, and a stub function to deal with recovered CUI items.
These parts will be connected to the refcountbt in a later patch.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2016-10-03 09:11:21 -07:00
Brian Foster
5cd9cee98b xfs: log recovery tracepoints to track current lsn and buffer submission
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>
2016-09-26 08:34:52 +10:00
Brian Foster
60a4a22251 xfs: update metadata LSN in buffers during log recovery
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>
2016-09-26 08:34:27 +10:00
Brian Foster
040c52c0aa xfs: don't warn on buffers not being recovered due to LSN
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>
2016-09-26 08:32:50 +10:00
Brian Foster
22db9af248 xfs: pass current lsn to log recovery buffer validation
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>
2016-09-26 08:32:07 +10:00
Brian Foster
12818d24db xfs: rework log recovery to submit buffers on LSN boundaries
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>
2016-09-26 08:22:16 +10:00
Darrick J. Wong
722e251770 xfs: remove the extents array from the rmap update done log item
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>
2016-08-03 12:28:43 +10:00
Darrick J. Wong
a650e8f98e xfs: add rmap btree block detection to log recovery
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>
2016-08-03 12:17:11 +10:00
Darrick J. Wong
9e88b5d867 xfs: log rmap intent items
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>
2016-08-03 12:09:48 +10:00
Darrick J. Wong
525488520a xfs: rmap btree requires more reserved free space
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>
2016-08-03 11:38:24 +10:00
Darrick J. Wong
dc42375d5f xfs: refactor redo intent item processing
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>
2016-08-03 11:23:49 +10:00
Darrick J. Wong
3ab78df2a5 xfs: rework xfs_bmap_free callers to use xfs_defer_ops
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>
2016-08-03 11:15:38 +10:00
Dave Chinner
2a4ad5894c Merge branch 'xfs-4.7-misc-fixes' into for-next 2016-05-20 10:33:17 +10:00
Christoph Hellwig
664b60f6ba xfs: improve kmem_realloc
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>
2016-04-06 09:47:01 +10:00
Christoph Hellwig
253f4911f2 xfs: better xfs_trans_alloc interface
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>
2016-04-06 09:19:55 +10:00
Dave Chinner
ab9d1e4f7b Merge branch 'xfs-misc-fixes-4.6-3' into for-next 2016-03-09 08:18:30 +11:00
Dave Chinner
7f0ed5461a Merge branch 'xfs-buf-macro-cleanup-4.6' into for-next 2016-03-07 09:31:00 +11:00
Dave Chinner
a2bbcb60ff Merge branch 'xfs-gut-icdinode-4.6' into for-next 2016-03-07 09:30:32 +11:00
Dave Chinner
c53473be45 Merge branch 'xfs-rt-fixes-4.6' into for-next 2016-03-07 09:29:04 +11:00
Dave Chinner
9deed09554 Merge branch 'xfs-torn-log-fixes-4.5' into for-next 2016-03-07 09:28:36 +11:00
Dave Chinner
a798011c8f xfs: reinitialise per-AG structures if geometry changes during recovery
If a crash occurs immediately after a filesystem grow operation, the
updated superblock geometry is found only in the log. After we
recover the log, the superblock is reread and re-initialised and so
has the new geometry in memory. If the new geometry has more AGs
than prior to the grow operation, then the new AGs will not have
in-memory xfs_perag structurea associated with them.

This will result in an oops when the first metadata buffer from a
new AG is looked up in the buffer cache, as the block lies within
the new geometry but then fails to find a perag structure on lookup.
This is easily fixed by simply re-initialising the perag structure
after re-reading the superblock at the conclusion of the first pahse
of log recovery.

This, however, does not fix the case of log recovery requiring
access to metadata in the newly grown space. Fortunately for us,
because the in-core superblock has not been updated, this will
result in detection of access beyond the end of the filesystem
and so recovery will fail at that point. If this proves to be
a problem, then we can address it separately to the current
reported issue.

Reported-by: Alex Lyakas <alex@zadarastorage.com>
Tested-by: Alex Lyakas <alex@zadarastorage.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
2016-03-07 08:39:36 +11:00
Brian Foster
7f6aff3a29 xfs: only run torn log write detection on dirty logs
XFS uses CRC verification over a sub-range of the head of the log to
detect and handle torn writes. This torn log write detection currently
runs unconditionally at mount time, regardless of whether the log is
dirty or clean. This is problematic in cases where a filesystem might
end up being moved across different, incompatible (i.e., opposite
byte-endianness) architectures.

The problem lies in the fact that log data is not necessarily written in
an architecture independent format. For example, certain bits of data
are written in native endian format. Further, the size of certain log
data structures differs (i.e., struct xlog_rec_header) depending on the
word size of the cpu. This leads to false positive crc verification
errors and ultimately failed mounts when a cleanly unmounted filesystem
is mounted on a system with an incompatible architecture from data that
was written near the head of the log.

Update the log head/tail discovery code to run torn write detection only
when the log is not clean. This means something other than an unmount
record resides at the head of the log and log recovery is imminent. It
is a requirement to run log recovery on the same type of host that had
written the content of the dirty log and therefore CRC failures are
legitimate corruptions in that scenario.

Reported-by: Jan Beulich <JBeulich@suse.com>
Tested-by: Jan Beulich <JBeulich@suse.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-03-07 08:22:22 +11:00
Brian Foster
717bc0ebca xfs: refactor in-core log state update to helper
Once the record at the head of the log is identified and verified, the
in-core log state is updated based on the record. This includes
information such as the current head block and cycle, the start block of
the last record written to the log, the tail lsn, etc.

Once torn write detection is conditional, this logic will need to be
reused. Factor the code to update the in-core log data structures into a
new helper function. This patch does not change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-03-07 08:22:22 +11:00
Brian Foster
65b99a08b3 xfs: refactor unmount record detection into helper
Once the mount sequence has identified the head and tail blocks of the
physical log, the record at the head of the log is located and examined
for an unmount record to determine if the log is clean. This currently
occurs after torn write verification of the head region of the log.

This must ultimately be separated from torn write verification and may
need to be called again if the log head is walked back due to a torn
write (to determine whether the new head record is an unmount record).
Separate this logic into a new helper function. This patch does not
change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-03-07 08:22:22 +11:00
Brian Foster
82ff6cc26e xfs: separate log head record discovery from verification
The code that locates the log record at the head of the log is buried in
the log head verification function. This is fine when torn write
verification occurs unconditionally, but this behavior is problematic
for filesystems that might be moved across systems with different
architectures.

In preparation for separating examination of the log head for unmount
records from torn write detection, lift the record location logic out of
the log verification function and into the caller. This patch does not
change behavior.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-03-07 08:22:22 +11:00
Dave Chinner
12877da584 xfs: remove XFS_BUF_ZEROFLAGS macro
The places where we use this macro already clear unnecessary IO
flags (e.g. through xfs_bwrite()) or never have unexpected IO flags
set on them in the first place (e.g. iclog buffers). Remove the
macro from these locations, and where necessary clear only the
specific flags that are conditional in the current buffer context.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-10 15:01:30 +11:00
Dave Chinner
b68c08219a xfs: remove XBF_WRITE flag wrapper macros
They only set/clear/check a flag, no need for obfuscating this
with a macro.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-02-10 15:01:11 +11:00