Commit Graph

3946 Commits

Author SHA1 Message Date
Ross Zwisler 6b524995a7 dax: remote unused fault wrappers
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>
2016-07-26 16:19:19 -07:00
Jann Horn 3e0a396546 xfs: fix type confusion in xfs_ioc_swapext
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>
2016-07-16 06:30:06 +09:00
Linus Torvalds d102a56edb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
2016-05-27 17:14:05 -07:00
Al Viro 5930122683 switch xattr_handler->set() to passing dentry and inode separately
preparation for similar switch in ->setxattr() (see the next commit for
rationale).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-27 15:39:43 -04:00
Linus Torvalds 315227f6da 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.
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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
2016-05-26 19:34:26 -07:00
Linus Torvalds 0b9210c9c8 xfs: update for 4.7-rc1
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
  ...
2016-05-26 10:13:40 -07:00
Dave Chinner 555b67e4e7 Merge branch 'xfs-4.7-inode-reclaim' into for-next 2016-05-20 10:34:00 +10:00
Dave Chinner 544ad71fc8 Merge branch 'xfs-4.7-error-cfg' into for-next 2016-05-20 10:33:38 +10:00
Dave Chinner 2a4ad5894c Merge branch 'xfs-4.7-misc-fixes' into for-next 2016-05-20 10:33:17 +10:00
Dave Chinner a7792aad64 Merge branch 'xfs-4.7-cleanup-attr-listent' into for-next 2016-05-20 10:32:35 +10:00
Dave Chinner 5b9113547f Merge branch 'xfs-4.7-optimise-inline-symlinks' into for-next 2016-05-20 10:32:10 +10:00
Dave Chinner d6bd9615ab Merge branch 'xfs-4.7-trans-type-cleanup' into for-next 2016-05-20 10:31:52 +10:00
Dave Chinner 8b7a242e53 Merge branch 'xfs-4.7-writeback-bio' into for-next 2016-05-20 10:31:29 +10:00
Christoph Hellwig 690a787122 xfs: fix warning in xfs_finish_page_writeback for non-debug builds
blockmask is unused if ASSERTs are disabled.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2016-05-20 10:29:15 +10:00
Matthew Wilcox 3dc2916107 dax: use sb_issue_zerout instead of calling dax_clear_sectors
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>
2016-05-18 12:16:56 -06:00
Linus Torvalds e34df3344d Merge branch 'work.lookups' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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()"
2016-05-18 10:28:45 -07:00
Dave Chinner 9f54180109 xfs: concurrent readdir hangs on data buffer locks
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>
2016-05-18 13:20:21 -04:00
Dave Chinner ad438c4038 xfs: move reclaim tagging functions
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>
2016-05-18 14:20:08 +10:00
Dave Chinner 545c0889d2 xfs: simplify inode reclaim tagging interfaces
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>
2016-05-18 14:11:41 +10:00
Dave Chinner 194293631d xfs: rename variables in xfs_iflush_cluster for clarity
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>
2016-05-18 14:09:46 +10:00
Dave Chinner 5a90e53e81 xfs: xfs_iflush_cluster has range issues
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>
2016-05-18 14:09:13 +10:00
Dave Chinner 8a17d7dded xfs: mark reclaimed inodes invalid earlier
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>
2016-05-18 14:09:12 +10:00
Dave Chinner 1f2dcfe89e xfs: xfs_inode_free() isn't RCU safe
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>
2016-05-18 14:01:53 +10:00
Alex Lyakas 32b43ab6fb xfs: optimise xfs_iext_destroy
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>
2016-05-18 14:01:52 +10:00
Dave Chinner 7d3aa7fe97 xfs: skip stale inodes in xfs_iflush_cluster
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>
2016-05-18 13:54:23 +10:00
Dave Chinner 51b07f30a7 xfs: fix inode validity check in xfs_iflush_cluster
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>
2016-05-18 13:54:22 +10:00
Dave Chinner b1438f4779 xfs: xfs_iflush_cluster fails to abort on error
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>
2016-05-18 13:53:42 +10:00
Dave Chinner 8179c03629 xfs: remove xfs_fs_evict_inode()
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>
2016-05-18 13:52:42 +10:00
Carlos Maiolino e6b3bb7896 xfs: add "fail at unmount" error handling configuration
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>
2016-05-18 11:11:27 +10:00
Carlos Maiolino e0a431b3a3 xfs: add configuration handlers for specific errors
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>
2016-05-18 11:09:28 +10:00
Carlos Maiolino a5ea70d25d xfs: add configuration of error failure speed
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>
2016-05-18 11:08:15 +10:00
Carlos Maiolino ef6a50fbb1 xfs: introduce table-based init for error behaviors
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>
2016-05-18 11:06:44 +10:00
Carlos Maiolino df3093907c xfs: add configurable error support to metadata buffers
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>
2016-05-18 11:05:33 +10:00
Carlos Maiolino ffd40ef697 xfs: introduce metadata IO error class
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>
2016-05-18 11:01:00 +10:00
Carlos Maiolino 192852be8b xfs: configurable error behavior via sysfs
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>
2016-05-18 10:58:51 +10:00
Brian Foster 9bdd9bd69b xfs: buffer ->bi_end_io function requires irq-safe lock
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>
2016-05-18 10:56:41 +10:00
Linus Torvalds c2e7b20705 Merge branch 'work.preadv2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
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
2016-05-17 15:05:23 -07:00
Toshi Kani 1e937cddd1 xfs: Add alignment check for DAX mount
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>
2016-05-17 00:44:12 -06:00
Jan Kara 02fbd13975 dax: Remove complete_unwritten argument
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>
2016-05-16 18:11:51 -06:00
Al Viro 3b0a3c1ac1 simple local filesystems: switch to ->iterate_shared()
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>
2016-05-02 19:49:32 -04:00
Al Viro 84695ffee7 Merge getxattr prototype change into work.lookups
The rest of work.xattr stuff isn't needed for this branch
2016-05-02 19:45:47 -04:00
Christoph Hellwig e259221763 fs: simplify the generic_write_sync prototype
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>
2016-05-01 19:58:39 -04:00
Christoph Hellwig dde0c2e798 fs: add IOCB_SYNC and IOCB_DSYNC
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>
2016-05-01 19:58:39 -04:00
Christoph Hellwig c8b8e32d70 direct-io: eliminate the offset argument to ->direct_IO
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>
2016-05-01 19:58:39 -04:00
Christoph Hellwig 13712713ca xfs: eliminate the pos variable in xfs_file_dio_aio_write
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-01 19:58:39 -04:00
Al Viro b296821a7c xattr_handler: pass dentry and inode as separate arguments of ->get()
... and do not assume they are already attached to each other

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-10 20:48:24 -04:00
Eryu Guan 6e3e6d55e5 xfs: mute some sparse warnings
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>
2016-04-06 09:47:21 +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
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