Commit Graph

273 Commits

Author SHA1 Message Date
Darrick J. Wong 9c92ee208b xfs: validate sb_logsunit is a multiple of the fs blocksize
Make sure the log stripe unit is sane before proceeding with mounting.
AFAICT this means that logsunit has to be 0, 1, or a multiple of the fs
block size.  Found this by setting the LSB of logsunit in xfs/350 and
watching the system crash as soon as we try to write to the log.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-10-26 15:38:29 -07:00
Brian Foster f1b92bbc23 xfs: drain the buffer LRU on mount
Log recovery of v4 filesystems does not use buffer verifiers because
log recovery historically can result in transient buffer corruption
when target buffers might be ahead of the log after a crash. v5
filesystems work around this problem with metadata LSN ordering.

While this log recovery verifier behavior is necessary on v4 supers,
it can result in leaving buffers around in the LRU without verifiers
attached for a significant amount of time. This leads to use of
unverified buffers while the filesystem is in active use, long after
recovery has completed.

To address this problem, drain all buffers from the LRU as a final
step of the log mount sequence. Note that this is done
unconditionally to provide a consistently clean cache footprint,
regardless of superblock version or log state. As a side effect,
this ensures that all cache resident, unverified buffers are
reclaimed after log recovery and therefore must be recreated with
verifiers on subsequent use.

Reported-by: Darrick Wong <darrick.wong@oracle.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
Thomas Meyer 749f24f33e xfs: Fix bool initialization/comparison
Bool initializations should use true and false. Bool tests don't need
comparisons.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-10-11 10:21:06 -07:00
Amir Goldstein 47c7d0b195 xfs: fix incorrect log_flushed on fsync
When calling into _xfs_log_force{,_lsn}() with a pointer
to log_flushed variable, log_flushed will be set to 1 if:
1. xlog_sync() is called to flush the active log buffer
AND/OR
2. xlog_wait() is called to wait on a syncing log buffers

xfs_file_fsync() checks the value of log_flushed after
_xfs_log_force_lsn() call to optimize away an explicit
PREFLUSH request to the data block device after writing
out all the file's pages to disk.

This optimization is incorrect in the following sequence of events:

 Task A                    Task B
 -------------------------------------------------------
 xfs_file_fsync()
   _xfs_log_force_lsn()
     xlog_sync()
        [submit PREFLUSH]
                           xfs_file_fsync()
                             file_write_and_wait_range()
                               [submit WRITE X]
                               [endio  WRITE X]
                             _xfs_log_force_lsn()
                               xlog_wait()
        [endio  PREFLUSH]

The write X is not guarantied to be on persistent storage
when PREFLUSH request in completed, because write A was submitted
after the PREFLUSH request, but xfs_file_fsync() of task A will
be notified of log_flushed=1 and will skip explicit flush.

If the system crashes after fsync of task A, write X may not be
present on disk after reboot.

This bug was discovered and demonstrated using Josef Bacik's
dm-log-writes target, which can be used to record block io operations
and then replay a subset of these operations onto the target device.
The test goes something like this:
- Use fsx to execute ops of a file and record ops on log device
- Every now and then fsync the file, store md5 of file and mark
  the location in the log
- Then replay log onto device for each mark, mount fs and compare
  md5 of file to stored value

Cc: Christoph Hellwig <hch@lst.de>
Cc: Josef Bacik <jbacik@fb.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-09-01 13:08:26 -07:00
Darrick J. Wong 799ea9e9c5 xfs: evict all inodes involved with log redo item
When we introduced the bmap redo log items, we set MS_ACTIVE on the
mountpoint and XFS_IRECOVERY on the inode to prevent unlinked inodes
from being truncated prematurely during log recovery.  This also had the
effect of putting linked inodes on the lru instead of evicting them.

Unfortunately, we neglected to find all those unreferenced lru inodes
and evict them after finishing log recovery, which means that we leak
them if anything goes wrong in the rest of xfs_mountfs, because the lru
is only cleaned out on unmount.

Therefore, evict unreferenced inodes in the lru list immediately
after clearing MS_ACTIVE.

Fixes: 17c12bcd30 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Cc: viro@ZenIV.linux.org.uk
Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-09-01 10:55:30 -07:00
Eric Sandeen 6f4a1eefdd xfs: toggle readonly state around xfs_log_mount_finish
When we do log recovery on a readonly mount, unlinked inode
processing does not happen due to the readonly checks in
xfs_inactive(), which are trying to prevent any I/O on a
readonly mount.

This is misguided - we do I/O on readonly mounts all the time,
for consistency; for example, log recovery.  So do the same
RDONLY flag twiddling around xfs_log_mount_finish() as we
do around xfs_log_mount(), for the same reason.

This all cries out for a big rework but for now this is a
simple fix to an obvious problem.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:23 -07:00
Eric Sandeen 757a69ef6c xfs: write unmount record for ro mounts
There are dueling comments in the xfs code about intent
for log writes when unmounting a readonly filesystem.

In xfs_mountfs, we see the intent:

/*
 * Now the log is fully replayed, we can transition to full read-only
 * mode for read-only mounts. This will sync all the metadata and clean
 * the log so that the recovery we just performed does not have to be
 * replayed again on the next mount.
 */

and it calls xfs_quiesce_attr(), but by the time we get to
xfs_log_unmount_write(), it returns early for a RDONLY mount:

 * Don't write out unmount record on read-only mounts.

Because of this, sequential ro mounts of a filesystem with
a dirty log will replay the log each time, which seems odd.

Fix this by writing an unmount record even for RO mounts, as long
as norecovery wasn't specified (don't write a clean log record
if a dirty log may still be there!) and the log device is
writable.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-08-22 09:22:23 -07:00
Darrick J. Wong 8204f8ddaa xfs: clear MS_ACTIVE after finishing log recovery
Way back when we established inode block-map redo log items, it was
discovered that we needed to prevent the VFS from evicting inodes during
log recovery because any given inode might be have bmap redo items to
replay even if the inode has no link count and is ultimately deleted,
and any eviction of an unlinked inode causes the inode to be truncated
and freed too early.

To make this possible, we set MS_ACTIVE so that inodes would not be torn
down immediately upon release.  Unfortunately, this also results in the
quota inodes not being released at all if a later part of the mount
process should fail, because we never reclaim the inodes.  So, set
MS_ACTIVE right before we do the last part of log recovery and clear it
immediately after we finish the log recovery so that everything
will be torn down properly if we abort the mount.

Fixes: 17c12bcd30 ("xfs: when replaying bmap operations, don't let unlinked inodes get reaped")
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
2017-08-17 12:40:33 -07:00
kbuild test robot 244e3dea58 xfs: fix semicolon.cocci warnings
fs/xfs/xfs_log.c:2092:38-39: Unneeded semicolon


 Remove unneeded semicolon.

Generated by: scripts/coccinelle/misc/semicolon.cocci

Fixes: d4ca1d550d ("xfs: dump transaction usage details on log reservation overrun")
CC: Brian Foster <bfoster@redhat.com>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-06-27 18:23:21 -07:00
Brian Foster 3e88a0078b xfs: replace log_badcrc_factor knob with error injection tag
Now that error injection tags support dynamic frequency adjustment,
replace the debug mode sysfs knob that controls log record CRC error
injection with an error injection tag.

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>
2017-06-27 18:23:21 -07:00
Darrick J. Wong 9e24cfd044 xfs: remove unneeded parameter from XFS_TEST_ERROR
Since we moved the injected error frequency controls to the mountpoint,
we can get rid of the last argument to XFS_TEST_ERROR.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
2017-06-27 18:23:20 -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
Brian Foster d4ca1d550d xfs: dump transaction usage details on log reservation overrun
If a transaction log reservation overrun occurs, the ticket data
associated with the reservation is dumped in xfs_log_commit_cil().
This occurs long after the transaction items and details have been
removed from the transaction and effectively lost. This limited set
of ticket data provides very little information to support debugging
transaction overruns based on the typical report.

To improve transaction log reservation overrun reporting, create a
helper to dump transaction details such as log items, log vector
data, etc., as well as the underlying ticket data for the
transaction. Move the overrun detection from xfs_log_commit_cil() to
xlog_cil_insert_items() so it occurs prior to migration of the
logged items to the CIL. Call the new helper such that it is able to
dump this transaction data before it is lost.

Also, warn on overrun to provide callstack context for the offending
transaction and include a few additional messages from
xlog_cil_insert_items() to display the reservation consumed locally
for overhead such as log vector headers, split region headers and
the context ticket. This provides a complete general breakdown of
the reservation consumption of a transaction when/if it happens to
overrun the reservation.

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>
2017-06-19 08:59:10 -07:00
Brian Foster 7d2d565346 xfs: separate shutdown from ticket reservation print helper
xlog_print_tic_res() pre-dates delayed logging and the committed
items list (CIL) and thus retains some factoring warts, such as hard
coded function names in the output and the fact that it induces a
shutdown.

In preparation for more detailed logging of regular transaction
overrun situations, refactor xlog_print_tic_res() to be slightly
more generic. Reword some of the warning messages and pull the
shutdown into the callers.

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>
2017-06-19 08:59:10 -07:00
Christoph Hellwig e2a641922a xfs: corruption needs to respect endianess too!
At least if we want to be able to recognize the pattern.  Add a missing
byte swap to the corruption injection case in xlog_sync.

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>
2017-04-25 09:40:42 -07:00
Brian Foster 696a562072 xfs: use dedicated log worker wq to avoid deadlock with cil wq
The log covering background task used to be part of the xfssyncd
workqueue. That workqueue was removed as of commit 5889608df ("xfs:
syncd workqueue is no more") and the associated work item scheduled
to the xfs-log wq. The latter is used for log buffer I/O completion.

Since xfs_log_worker() can invoke a log flush, a deadlock is
possible between the xfs-log and xfs-cil workqueues. Consider the
following codepath from xfs_log_worker():

xfs_log_worker()
  xfs_log_force()
    _xfs_log_force()
      xlog_cil_force()
        xlog_cil_force_lsn()
          xlog_cil_push_now()
            flush_work()

The above is in xfs-log wq context and blocked waiting on the
completion of an xfs-cil work item. Concurrently, the cil push in
progress can end up blocked here:

xlog_cil_push_work()
  xlog_cil_push()
    xlog_write()
      xlog_state_get_iclog_space()
        xlog_wait(&log->l_flush_wait, ...)

The above is in xfs-cil context waiting on log buffer I/O
completion, which executes in xfs-log wq context. In this scenario
both workqueues are deadlocked waiting on eachother.

Add a new workqueue specifically for the high level log covering and
ail pushing worker, as was the case prior to commit 5889608df.

Diagnosed-by: David Jeffery <djeffery@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>
2017-04-03 15:18:15 -07:00
Christoph Hellwig 84a4620cfe xfs: don't print warnings when xfs_log_force fails
There are only two reasons for xfs_log_force / xfs_log_force_lsn to fail:
one is an I/O error, for which xlog_bdstrat already logs a warning, and
the second is an already shutdown log due to a previous I/O errors.  In
the latter case we'll already have a previous indication for the actual
error, but the large stream of misleading warnings from xfs_log_force
will probably scroll it out of the message buffer.

Simply removing the warnings thus makes the XFS log reporting significantly
better.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2017-01-09 13:45:01 -08:00
Dave Chinner 9807b773da Merge branch 'xfs-4.10-misc-fixes-4' into for-next 2016-12-09 16:56:26 +11:00
Dave Chinner 2291dab2c9 xfs: Always flush caches when integrity is required
There is no reason anymore for not issuing device integrity
operations when teh filesystem requires ordering or data integrity
guarantees. We should always issue cache flushes and FUA writes
where necessary and let the underlying storage optimise them as
necessary for correct integrity operation.

Signed-Off-By: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-12-09 16:49:54 +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
Dave Chinner bbfeb6141f Merge branch 'xfs-4.8-buf-fixes' into for-next 2016-07-20 11:53:35 +10:00
Brian Foster c891c30a4d xfs: exclude never-released buffers from buftarg I/O accounting
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>
2016-07-20 11:13:43 +10:00
Eric Sandeen 0d5a75e9e2 xfs: make several functions static
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>
2016-06-01 17:38:15 +10:00
Dave Chinner 2a4ad5894c Merge branch 'xfs-4.7-misc-fixes' into for-next 2016-05-20 10:33:17 +10:00
Carlos Maiolino 9f27889f3a xfs: Add caller function output to xfs_log_force tracepoint
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>
2016-04-06 09:46:30 +10:00
Christoph Hellwig 710b1e2c29 xfs: remove transaction types
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>
2016-04-06 09:20:36 +10:00
Darrick J. Wong 5110cd82ca xfs: use named array initializers for log item dumping
Use named array initializers for the string arrays used to dump log
items, rather than depending on the order being maintained 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>
2016-03-07 08:40:03 +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
Dave Chinner 1157b32c73 xfs: remove XBF_ASYNC 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
Dave Chinner b0388bf108 xfs: remove XBF_DONE 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
Dave Chinner 7eeabbd4b6 Merge branch 'xfs-misc-fixes-for-4.5' into for-next 2016-01-05 08:08:35 +11:00
Brian Foster 609adfc2ed xfs: debug mode log record crc error injection
XFS now uses CRC verification over a limited section of the log to
detect torn writes prior to a crash. This is difficult to test directly
due to the timing and hardware requirements to cause a short write.

Add a mechanism to inject CRC errors into log records to facilitate
testing torn write detection during log recovery. This mechanism is
dangerous and can result in filesystem corruption. Thus, it is only
available in DEBUG mode for testing/development purposes. Set a non-zero
value to the following sysfs entry to enable error injection:

	/sys/fs/xfs/<dev>/log/log_badcrc_factor

Once enabled, XFS intentionally writes an invalid CRC to a log record at
some random point in the future based on the provided frequency. The
filesystem immediately shuts down once the record has been written to
the physical log to prevent metadata writeback (e.g., AIL insertion)
once the log write completes. This helps reasonably simulate a torn
write to the log as the affected record must be safe to discard. The
next mount after the intentional shutdown requires log recovery and
should detect and recover from the torn write.

Note again that this _will_ result in data loss or worse. For testing
and development purposes only!

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-05 07:41:16 +11:00
Darrick J. Wong 9b434a347c xfs: fix log ticket type printing
Update the log ticket reservation type printing code to reflect
all the types of log tickets, to avoid incorrect debug output and
avoid running off the end of the array.

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>
2016-01-04 16:11:42 +11:00
Dave Chinner 316433beda Merge branch 'xfs-logging-fixes' into for-next 2015-10-12 18:37:58 +11:00
Bill O'Donnell ff6d6af235 xfs: per-filesystem stats counter implementation
This patch modifies the stats counting macros and the callers
to those macros to properly increment, decrement, and add-to
the xfs stats counts. The counts for global and per-fs stats
are correctly advanced, and cleared by writing a "1" to the
corresponding clear file.

global counts: /sys/fs/xfs/stats/stats
per-fs counts: /sys/fs/xfs/sda*/stats/stats

global clear:  /sys/fs/xfs/stats/stats_clear
per-fs clear:  /sys/fs/xfs/sda*/stats/stats_clear

[dchinner: cleaned up macro variables, removed CONFIG_FS_PROC around
 stats structures and macros. ]

Signed-off-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12 18:21:22 +11:00
Eric Sandeen 91f9f5fe1e xfs: avoid null *src in memcpy call in xlog_write
The gcc undefined behavior sanitizer caught this; surely
any sane memcpy implementation will no-op if size == 0,
but behavior with a *src of NULL is technically undefined
(declared nonnull), so avoid it here.

We are actually in this situation frequently via
xlog_commit_record(), because:

        struct xfs_log_iovec reg = {
                .i_addr = NULL,
                .i_len = 0,
                .i_type = XLOG_REG_TYPE_COMMIT,
        };

Reported-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12 16:04:15 +11:00
Brian Foster a45086e27d xfs: validate metadata LSNs against log on v5 superblocks
Since the onset of v5 superblocks, the LSN of the last modification has
been included in a variety of on-disk data structures. This LSN is used
to provide log recovery ordering guarantees (e.g., to ensure an older
log recovery item is not replayed over a newer target data structure).

While this works correctly from the point a filesystem is formatted and
mounted, userspace tools have some problematic behaviors that defeat
this mechanism. For example, xfs_repair historically zeroes out the log
unconditionally (regardless of whether corruption is detected). If this
occurs, the LSN of the filesystem is reset and the log is now in a
problematic state with respect to on-disk metadata structures that might
have a larger LSN. Until either the log catches up to the highest
previously used metadata LSN or each affected data structure is modified
and written out without incident (which resets the metadata LSN), log
recovery is susceptible to filesystem corruption.

This problem is ultimately addressed and repaired in the associated
userspace tools. The kernel is still responsible to detect the problem
and notify the user that something is wrong. Check the superblock LSN at
mount time and fail the mount if it is invalid. From that point on,
trigger verifier failure on any metadata I/O where an invalid LSN is
detected. This results in a filesystem shutdown and guarantees that we
do not log metadata changes with invalid LSNs on disk. Since this is a
known issue with a known recovery path, present a warning to instruct
the user how to recover.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-12 15:59:25 +11:00
Dave Chinner 5be203ad11 Merge branch 'xfs-efi-rework' into for-next 2015-08-19 10:10:47 +10:00
Brian Foster a3f2001465 xfs: checksum log record ext headers based on record size
The first 4 bytes of every basic block in the physical log is stamped
with the current lsn. To support this mechanism, the log record header
(first block of each new log record) contains space for the original
first byte of each log record block before it is replaced with the lsn.
The log record header has space for 32k worth of blocks. The version 2
log adds new extended record headers for each additional 32k worth of
blocks beyond what is supported by the record header.

The log record checksum incorporates the log record header, the extended
headers and the record payload. xlog_cksum() checksums the extended
headers based on log->l_iclog_heads, which specifies the number of
extended headers in a log record based on the log buffer size mount
option. The log buffer size is variable, however, and thus means the
checksum can be calculated differently based on how a filesystem is
mounted. This is problematic if a filesystem crashes and recovery occurs
on a subsequent mount using a different log buffer size. For example,
crash an active filesystem that is mounted with the default (32k)
logbsize, attempt remount/recovery using '-o logbsize=64k' and the mount
fails on or warns about log checksum failures.

To avoid this problem, update xlog_cksum() to calculate the checksum
based on the size of the log buffer according to the log record. The
size is already included in the h_size field of the log record header
and thus is available at log recovery time. Extended log record headers
are also only written when the log record is large enough to require
them. This makes checksum calculation of log records consistent with the
extended record header mechanism as well as how on-disk records are
checksummed with various log buffer size mount options.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 09:59:50 +10:00
Brian Foster f0b2efad16 xfs: don't leave EFIs on AIL on mount failure
Log recovery occurs in two phases at mount time. In the first phase,
EFIs and EFDs are processed and potentially cancelled out. EFIs without
EFD objects are inserted into the AIL for processing and recovery in the
second phase. xfs_mountfs() runs various other operations between the
phases and is thus subject to failure. If failure occurs after the first
phase but before the second, pending EFIs sit on the AIL, pin it and
cause the mount to hang.

Update the mount sequence to ensure that pending EFIs are cancelled in
the event of failure. Add a recovery cancellation mechanism to iterate
the AIL and cancel all EFI items when requested. Plumb cancellation
support through the log mount finish helper and update xfs_mountfs() to
invoke cancellation in the event of failure after recovery has started.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-19 09:58:36 +10:00
Joe Perches f41febd2eb xfs: Use consistent logging message prefixes
The second and subsequent lines of multi-line logging messages
are not prefixed with the same information as the first line.

Separate messages with newlines into multiple calls to ensure
consistent prefixing and allow easier grep use.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-07-29 11:52:04 +10:00
Dave Chinner de50e16ffa Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
Christoph Hellwig b2a922cd6c xfs: remove xfs_caddr_t
Just use char pointers directly instead of the confusing typedef to a
pointer type.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 09:45:10 +10:00
Christoph Hellwig 5809d5e083 xfs: use void pointers in log validation helpers
Compared to char pointers this saves us a lot of casting effort.  Also
add another local variable to make the code easier to read.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 09:44:47 +10:00
Christoph Hellwig db9d67d6b0 xfs: remove __psint_t and __psunsigned_t
Replace uses of __psint_t with the proper uintptr_t and ptrdiff_t types,
and remove the defintions of __psint_t and __psunsigned_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 09:43:32 +10:00
Christoph Hellwig f78c390107 xfs: fix xfs_log_done interface
Instead of the confusing flags argument pass a boolean flag to indicate if
we want to release or regrant a log reservation.

Also ensure that xfs_log_done always drop the reference on the log ticket,
to both simplify the code and make the logic in xfs_trans_roll easier
to understand.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 13:48:20 +10:00
Dave Chinner 465e2def7c Merge branch 'xfs-sb-logging-rework' into for-next
Conflicts:
	fs/xfs/xfs_mount.c
2015-01-22 09:20:53 +11:00
Dave Chinner 61e63ecb57 xfs: consolidate superblock logging functions
We now have several superblock loggin functions that are identical
except for the transaction reservation and whether it shoul dbe a
synchronous transaction or not. Consolidate these all into a single
function, a single reserveration and a sync flag and call it
xfs_sync_sb().

Also, xfs_mod_sb() is not really a modification function - it's the
operation of logging the superblock buffer. hence change the name of
it to reflect this.

Note that we have to change the mp->m_update_flags that are passed
around at mount time to a boolean simply to indicate a superblock
update is needed.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-01-22 09:10:31 +11:00
Eric Sandeen 77af574eef xfs: remove extra newlines from xfs messages
xfs_warn() and friends add a newline by default, but some
messages add another one.

Particularly for the failing write message below, this can
waste a lot of console real estate!

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-24 09:47:27 +11:00