Commit Graph

160 Commits

Author SHA1 Message Date
Vladimir Davydov 5d097056c9 kmemcg: account certain kmem allocations to memcg
Mark those kmem allocations that are known to be easily triggered from
userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
memcg.  For the list, see below:

 - threadinfo
 - task_struct
 - task_delay_info
 - pid
 - cred
 - mm_struct
 - vm_area_struct and vm_region (nommu)
 - anon_vma and anon_vma_chain
 - signal_struct
 - sighand_struct
 - fs_struct
 - files_struct
 - fdtable and fdtable->full_fds_bits
 - dentry and external_name
 - inode for all filesystems. This is the most tedious part, because
   most filesystems overwrite the alloc_inode method.

The list is far from complete, so feel free to add more objects.
Nevertheless, it should be close to "account everything" approach and
keep most workloads within bounds.  Malevolent users will be able to
breach the limit, but this was possible even with the former "account
everything" approach (simply because it did not account everything in
fact).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Vladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14 16:00:49 -08:00
Markus Elfring a841b64df2 XFS: Use a signed return type for suffix_kstrtoint()
The return type "unsigned long" was used by the suffix_kstrtoint()
function even though it will eventually return a negative error code.
Improve this implementation detail by using the type "int" instead.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2016-01-04 16:13:21 +11:00
Dave Chinner 4e14e49a91 Merge branch 'xfs-misc-fixes-for-4.4-3' into for-next 2015-11-10 10:20:48 +11:00
Chris Mason 7a29ac474a xfs: give all workqueues rescuer threads
We're consistently hitting deadlocks here with XFS on recent kernels.
After some digging through the crash files, it looks like everyone in
the system is waiting for XFS to reclaim memory.

Something like this:

PID: 2733434  TASK: ffff8808cd242800  CPU: 19  COMMAND: "java"
 #0 [ffff880019c53588] __schedule at ffffffff818c4df2
 #1 [ffff880019c535d8] schedule at ffffffff818c5517
 #2 [ffff880019c535f8] _xfs_log_force_lsn at ffffffff81316348
 #3 [ffff880019c53688] xfs_log_force_lsn at ffffffff813164fb
 #4 [ffff880019c536b8] xfs_iunpin_wait at ffffffff8130835e
 #5 [ffff880019c53728] xfs_reclaim_inode at ffffffff812fd453
 #6 [ffff880019c53778] xfs_reclaim_inodes_ag at ffffffff812fd8c7
 #7 [ffff880019c53928] xfs_reclaim_inodes_nr at ffffffff812fe433
 #8 [ffff880019c53958] xfs_fs_free_cached_objects at ffffffff8130d3b9
 #9 [ffff880019c53968] super_cache_scan at ffffffff811a6f73
#10 [ffff880019c539c8] shrink_slab at ffffffff811460e6
#11 [ffff880019c53aa8] shrink_zone at ffffffff8114a53f
#12 [ffff880019c53b48] do_try_to_free_pages at ffffffff8114a8ba
#13 [ffff880019c53be8] try_to_free_pages at ffffffff8114ad5a
#14 [ffff880019c53c78] __alloc_pages_nodemask at ffffffff8113e1b8
#15 [ffff880019c53d88] alloc_kmem_pages_node at ffffffff8113e671
#16 [ffff880019c53dd8] copy_process at ffffffff8104f781
#17 [ffff880019c53ec8] do_fork at ffffffff8105129c
#18 [ffff880019c53f38] sys_clone at ffffffff810515b6
#19 [ffff880019c53f48] stub_clone at ffffffff818c8e4d

xfs_log_force_lsn is waiting for logs to get cleaned, which is waiting
for IO, which is waiting for workers to complete the IO which is waiting
for worker threads that don't exist yet:

PID: 2752451  TASK: ffff880bd6bdda00  CPU: 37  COMMAND: "kworker/37:1"
 #0 [ffff8808d20abbb0] __schedule at ffffffff818c4df2
 #1 [ffff8808d20abc00] schedule at ffffffff818c5517
 #2 [ffff8808d20abc20] schedule_timeout at ffffffff818c7c6c
 #3 [ffff8808d20abcc0] wait_for_completion_killable at ffffffff818c6495
 #4 [ffff8808d20abd30] kthread_create_on_node at ffffffff8106ec82
 #5 [ffff8808d20abdf0] create_worker at ffffffff8106752f
 #6 [ffff8808d20abe40] worker_thread at ffffffff810699be
 #7 [ffff8808d20abec0] kthread at ffffffff8106ef59
 #8 [ffff8808d20abf50] ret_from_fork at ffffffff818c8ac8

I think we should be using WQ_MEM_RECLAIM to make sure this thread
pool makes progress when we're not able to allocate new workers.

[dchinner: make all workqueues WQ_MEM_RECLAIM]

Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-11-10 10:10:34 +11:00
Dave Chinner 2da5c4b05a Merge branch 'xfs-misc-fixes-for-4.4-2' into for-next 2015-11-03 13:27:58 +11:00
Darrick J. Wong af3b63822e xfs: don't leak uuid table on rmmod
Don't leak the UUID table when the module is unloaded.
(Found with kmemleak.)

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>
2015-11-03 13:06:34 +11:00
Dan Carpenter f9d460b341 xfs: fix an error code in xfs_fs_fill_super()
If alloc_percpu() fails, we accidentally return PTR_ERR(NULL), which
means success, but we intended to return -ENOMEM.

Fixes: 225e463558 ('xfs: per-filesystem stats in sysfs')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-10-19 08:42:47 +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
Bill O'Donnell 225e463558 xfs: per-filesystem stats in sysfs
This patch implements per-filesystem stats objects in sysfs. It
depends on the application of the previous patch series that
develops the infrastructure to support both xfs global stats and
xfs per-fs stats in sysfs.

Stats objects are instantiated when an xfs filesystem is mounted
and deleted on unmount. With this patch, the stats directory is
created and populated with the familiar stats and stats_clear files.
Example:
        /sys/fs/xfs/sda9/stats/stats
        /sys/fs/xfs/sda9/stats/stats_clear

With this patch, the individual counts within the new per-fs
stats file(s) remain at zero. Functions that use the the macros
to increment, decrement, and add-to the per-fs stats counts will
be covered in a separate new patch to follow this one. Note that
the counts within the global stats file (/sys/fs/xfs/stats/stats)
advance normally and can be cleared as it was prior to this patch.

[dchinner: move setup/teardown to xfs_fs_{fill|put}_super() so
it is down before/after any path that uses the per-mount stats. ]

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 18:21:19 +11:00
Bill O'Donnell 80529c45ab xfs: pass xfsstats structures to handlers and macros
This patch is the next step toward per-fs xfs stats. The patch makes
the show and clear routines able to handle any stats structure
associated with a kobject.

Instead of a single global xfsstats structure, add kobject and a pointer
to a per-cpu struct xfsstats. Modify the macros that manipulate the stats
accordingly: XFS_STATS_INC, XFS_STATS_DEC, and XFS_STATS_ADD now access
xfsstats->xs_stats.

The sysfs functions need to get from the kobject back to the xfsstats
structure which contains it, and pass the pointer to the ->xs_stats
percpu structure into the show & clear routines.

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 05:19:45 +11:00
Bill O'Donnell bb230c1247 xfs: create global stats and stats_clear in sysfs
Currently, xfs global stats are in procfs. This patch introduces
(replicates) the global stats in sysfs. Additionally a stats_clear file
is introduced in sysfs.

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 05:15:45 +11:00
Linus Torvalds 77a78806c7 xfs: updates for 4.3-rc1
This update contains:
 o large rework of EFI/EFD lifecycle handling to fix log recovery corruption
   issues, crashes and unmount hangs
 o separate metadata UUID on disk to enable changing boot label UUID for v5
   filesystems
 o fixes for gcc miscompilation on certain platforms and optimisation levels
 o remote attribute allocation and recovery corruption fixes
 o inode lockdep annotation rework to fix bugs with too many subclasses
 o directory inode locking changes to prevent lockdep false positives
 o a handful of minor corruption fixes
 o various other small cleanups and bug fixes
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Merge tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs updates from Dave Chinner:
 "There isn't a whole lot to this update - it's mostly bug fixes and
  they are spread pretty much all over XFS.  There are some corruption
  fixes, some fixes for log recovery, some fixes that prevent unount
  from hanging, a lockdep annotation rework for inode locking to prevent
  false positives and the usual random bunch of cleanups and minor
  improvements.

  Deatils:

   - large rework of EFI/EFD lifecycle handling to fix log recovery
     corruption issues, crashes and unmount hangs

   - separate metadata UUID on disk to enable changing boot label UUID
     for v5 filesystems

   - fixes for gcc miscompilation on certain platforms and optimisation
     levels

   - remote attribute allocation and recovery corruption fixes

   - inode lockdep annotation rework to fix bugs with too many
     subclasses

   - directory inode locking changes to prevent lockdep false positives

   - a handful of minor corruption fixes

   - various other small cleanups and bug fixes"

* tag 'xfs-for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (42 commits)
  xfs: fix error gotos in xfs_setattr_nonsize
  xfs: add mssing inode cache attempts counter increment
  xfs: return errors from partial I/O failures to files
  libxfs: bad magic number should set da block buffer error
  xfs: fix non-debug build warnings
  xfs: collapse allocsize and biosize mount option handling
  xfs: Fix file type directory corruption for btree directories
  xfs: lockdep annotations throw warnings on non-debug builds
  xfs: Fix uninitialized return value in xfs_alloc_fix_freelist()
  xfs: inode lockdep annotations broke non-lockdep build
  xfs: flush entire file on dio read/write to cached file
  xfs: Fix xfs_attr_leafblock definition
  libxfs: readahead of dir3 data blocks should use the read verifier
  xfs: stop holding ILOCK over filldir callbacks
  xfs: clean up inode lockdep annotations
  xfs: swap leaf buffer into path struct atomically during path shift
  xfs: relocate sparse inode mount warning
  xfs: dquots should be stamped with sb_meta_uuid
  xfs: log recovery needs to validate against sb_meta_uuid
  xfs: growfs not aware of sb_meta_uuid
  ...
2015-09-07 13:28:32 -07:00
Kees Cook a068acf2ee fs: create and use seq_show_option for escaping
Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Jan Kara <jack@suse.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-09-04 16:54:41 -07:00
Eric Sandeen 2ccf4a9b18 xfs: collapse allocsize and biosize mount option handling
The allocsize and biosize mount options are handled identically,
other than allocsize accepting suffixes.  suffix_kstrtoint handles
bare numbers just fine too, so these can be collapsed.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-08-25 10:05:13 +10:00
Brian Foster 1b867d3ab5 xfs: relocate sparse inode mount warning
The sparse inodes feature is currently considered experimental. We warn
at mount time from xfs_mount_validate_sb(). This function is part of the
superblock verifier codepath, however, which means it could be invoked
repeatedly on superblock reads or writes. This is currently only
noticeable from userspace, where mkfs produces multiple warnings at
format time.

As mkfs warnings were not the intent of this change, relocate the mount
time warning to xfs_fs_fill_super(), which is only invoked once and only
in kernel space.

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 10:32:14 +10:00
Dave Chinner cbe4dab119 xfs: add initial DAX support
Add initial DAX support to XFS. To do this we need a new mount
option to turn DAX on filesystem, and we need to propagate this into
the inode flags whenever an inode is instantiated so that the
per-inode checks throughout the code Do The Right Thing.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 09:19:18 +10:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Dave Chinner 6a63ef064b Merge branch 'xfs-misc-fixes-for-4.1-3' into for-next
Conflicts:
	fs/xfs/xfs_iops.c
2015-04-13 11:40:16 +10:00
Eric Sandeen bbe051c841 xfs: disallow ro->rw remount on norecovery mount
There's a bit of a loophole in norecovery mount handling right
now: an initial mount must be readonly, but nothing prevents
a mount -o remount,rw from producing a writable, unrecovered
xfs filesystem.

It might be possible to try to perform a log recovery when this
is requested, but I'm not sure it's worth the effort.  For now,
simply disallow this sort of transition.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-04-13 11:25:41 +10:00
Dave Chinner 2b93681f59 Merge branch 'xfs-misc-fixes-for-4.1-2' into for-next
Conflicts:
	fs/xfs/libxfs/xfs_bmap.c
	fs/xfs/xfs_inode.c
2015-03-25 15:12:30 +11:00
Joe Perches 5e9383f97e xfs: Fix incorrect positive ENOMEM return
added a positive error return value.

This value filters up through the return layers and should be
negative as the other return values are in the same function.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-03-25 15:00:24 +11:00
Dave Chinner 88e8fda99a Merge branch 'xfs-mmap-lock' into for-next 2015-02-24 10:27:47 +11:00
Dave Chinner 4225441a1e Merge branch 'xfs-generic-sb-counters' into for-next
Conflicts:
	fs/xfs/xfs_super.c
2015-02-24 10:27:28 +11:00
Eric Sandeen 444a702231 xfs: remove deprecated mount options
We recently removed deprecated sysctls; may as well
remove deprecated mount options as well, we've stated
that they'd be gone by now in the docs.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:17:04 +11:00
Eric Sandeen 3b9ce795fa xfs: log unmount events on console
There are times, when doing triage and forensics,
that we would like to know whether a filesystem was unmounted,
or if the plug was pulled without a clean unmount.  Log
unmounts at the same level (NOTICE) as we log mounts.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-24 10:13:37 +11:00
Dave Chinner 653c60b633 xfs: introduce mmap/truncate lock
Right now we cannot serialise mmap against truncate or hole punch
sanely. ->page_mkwrite is not able to take locks that the read IO
path normally takes (i.e. the inode iolock) because that could
result in lock inversions (read - iolock - page fault - page_mkwrite
- iolock) and so we cannot use an IO path lock to serialise page
write faults against truncate operations.

Instead, introduce a new lock that is used *only* in the
->page_mkwrite path that is the equivalent of the iolock. The lock
ordering in a page fault is i_mmaplock -> page lock -> i_ilock,
and so in truncate we can i_iolock -> i_mmaplock and so lock out
new write faults during the process of truncation.

Because i_mmap_lock is outside the page lock, we can hold it across
all the same operations we hold the i_iolock for. The only
difference is that we never hold the i_mmaplock in the normal IO
path and so do not ever have the possibility that we can page fault
inside it. Hence there are no recursion issues on the i_mmap_lock
and so we can use it to serialise page fault IO against inode
modification operations that affect the IO path.

This patch introduces the i_mmaplock infrastructure, lockdep
annotations and initialisation/destruction code. Use of the new lock
will be in subsequent patches.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:43:37 +11:00
Dave Chinner 5681ca4006 xfs: Remove icsb infrastructure
Now that the in-core superblock infrastructure has been replaced with
generic per-cpu counters, we don't need it anymore. Nuke it from
orbit so we are sure that it won't haunt us again...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:22:31 +11:00
Dave Chinner 0d485ada40 xfs: use generic percpu counters for free block counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. The free block counter is
special in that it is used for ENOSPC detection outside transaction
contexts for for delayed allocation. This means that the counter
needs to be accurate at zero. The current per-cpu counter code jumps
through lots of hoops to ensure we never run past zero, but we don't
need to make all those jumps with the generic counter
implementation.

The generic counter implementation allows us to pass a "batch"
threshold at which the addition/subtraction to the counter value
will be folded back into global value under lock. We can use this
feature to reduce the batch size as we approach 0 in a very similar
manner to the existing counters and their rebalance algorithm. If we
use a batch size of 1 as we approach 0, then every addition and
subtraction will be done against the global value and hence allow
accurate detection of zero threshold crossing.

Hence we can replace the handrolled, accurate-at-zero counters with
generic percpu counters.

Note: this removes just enough of the icsb infrastructure to compile
without warnings. The rest will go in subsequent commits.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:22:03 +11:00
Dave Chinner e88b64ea1f xfs: use generic percpu counters for free inode counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. The free inode counter is not
used for any limit enforcement - the per-AG free inode counters are
used during allocation to determine if there are inode available for
allocation.

Hence we don't need any of the complexity of the hand-rolled
counters and we can simply replace them with generic per-cpu
counters similar to the inode counter.

This version introduces a xfs_mod_ifree() helper function from
Christoph Hellwig.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:19:53 +11:00
Dave Chinner 501ab32387 xfs: use generic percpu counters for inode counter
XFS has hand-rolled per-cpu counters for the superblock since before
there was any generic implementation. There are some warts around
the  use of them for the inode counter as the hand rolled counter is
designed to be accurate at zero, but has no specific accurracy at
any other value. This design causes problems for the maximum inode
count threshold enforcement, as there is no trigger that balances
the counters as they get close tothe maximum threshold.

Instead of designing new triggers for balancing, just replace the
handrolled per-cpu counter with a generic counter.  This enables us
to update the counter through the normal superblock modification
funtions, but rather than do that we add a xfs_mod_icount() helper
function (from Christoph Hellwig) and keep the percpu counter
outside the superblock in the struct xfs_mount.

This means we still need to initialise the per-cpu counter
specifically when we read the superblock, and vice versa when we
log/write it, but it does mean that we don't need to change any
other code.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-23 21:19:28 +11:00
Vladimir Davydov 4101b62435 fs: consolidate {nr,free}_cached_objects args in shrink_control
We are going to make FS shrinkers memcg-aware.  To achieve that, we will
have to pass the memcg to scan to the nr_cached_objects and
free_cached_objects VFS methods, which currently take only the NUMA node
to scan.  Since the shrink_control structure already holds the node, and
the memcg to scan will be added to it when we introduce memcg-aware
vmscan, let us consolidate the methods' arguments in this structure to
keep things clean.

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Suggested-by: Dave Chinner <david@fromorbit.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Greg Thelen <gthelen@google.com>
Cc: Glauber Costa <glommer@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-12 18:54:08 -08:00
Dave Chinner bad962662d Merge branch 'xfs-misc-fixes-for-3.20-4' into for-next 2015-02-10 09:24:25 +11:00
Eric Sandeen 01f9882eac xfs: report proper f_files in statfs if we overshoot imaxpct
Normally, a statfs syscall reports m_maxicount as f_files
(total file nodes in file system) because it is supposed
to be the upper limit for dynamically-allocated inodes.

It's possible, however, to overshoot imaxpct / m_maxicount.
If this happens, we should report the actual number of allocated
inodes, which is contained in sb_icount.  Add one more adjustment
to the statfs code to make this happen.

Reported-by: Alexander Tsvetkov <alexander.tsvetkov@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-02-06 09:53:02 +11:00
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
Dave Chinner 4d11a40239 xfs: remove bitfield based superblock updates
When we log changes to the superblock, we first have to write them
to the on-disk buffer, and then log that. Right now we have a
complex bitfield based arrangement to only write the modified field
to the buffer before we log it.

This used to be necessary as a performance optimisation because we
logged the superblock buffer in every extent or inode allocation or
freeing, and so performance was extremely important. We haven't done
this for years, however, ever since the lazy superblock counters
pulled the superblock logging out of the transaction commit
fast path.

Hence we have a bunch of complexity that is not necessary that makes
writing the in-core superblock to disk much more complex than it
needs to be. We only need to log the superblock now during
management operations (e.g. during mount, unmount or quota control
operations) so it is not a performance critical path anymore.

As such, remove the complex field based logging mechanism and
replace it with a simple conversion function similar to what we use
for all other on-disk structures.

This means we always log the entirity of the superblock, but again
because we rarely modify the superblock this is not an issue for log
bandwidth or CPU time. Indeed, if we do log the superblock
frequently, delayed logging will minimise the impact of this
overhead.

[Fixed gquota/pquota inode sharing regression noticed by bfoster.]

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 09:10:26 +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
Linus Torvalds c05e14f7b3 xfs: update for 3.19-rc1
This update contains:
 o more on-disk format header consolidation
 o move some structures shared with userspace to libxfs
 o new per-mount workqueue to fix for deadlocks between nested loop
   mounted filesystems
 o various bug fixes for ENOSPC, stats, quota off and preallocation
 o a bunch of compiler warning fixes for set-but-unused variables
 o various code cleanups
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Merge tag 'xfs-for-linus-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs

Pull xfs update from Dave Chinner:
 "There's relatively little change in this update; it is mainly bug
  fixes, cleanups and more of the on-going libxfs restructuring and
  on-disk format header consolidation work.

  Details:
   - more on-disk format header consolidation
   - move some structures shared with userspace to libxfs
   - new per-mount workqueue to fix for deadlocks between nested loop
     mounted filesystems
   - various bug fixes for ENOSPC, stats, quota off and preallocation
   - a bunch of compiler warning fixes for set-but-unused variables
   - various code cleanups"

* tag 'xfs-for-linus-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (24 commits)
  xfs: split metadata and log buffer completion to separate workqueues
  xfs: fix set-but-unused warnings
  xfs: move type conversion functions to xfs_dir.h
  xfs: move ftype conversion functions to libxfs
  xfs: lobotomise xfs_trans_read_buf_map()
  xfs: active inodes stat is broken
  xfs: cleanup xfs_bmse_merge returns
  xfs: cleanup xfs_bmse_shift_one goto mess
  xfs: fix premature enospc on inode allocation
  xfs: overflow in xfs_iomap_eof_align_last_fsb
  xfs: fix simple_return.cocci warning in xfs_bmse_shift_one
  xfs: fix simple_return.cocci warning in xfs_file_readdir
  libxfs: fix simple_return.cocci warnings
  xfs: remove unnecessary null checks
  xfs: merge xfs_inum.h into xfs_format.h
  xfs: move most of xfs_sb.h to xfs_format.h
  xfs: merge xfs_ag.h into xfs_format.h
  xfs: move acl structures to xfs_format.h
  xfs: merge xfs_dinode.h into xfs_format.h
  xfs: catch invalid negative blknos in _xfs_buf_find()
  ...
2014-12-12 09:48:17 -08:00
Dave Chinner 6044e4386c Merge branch 'xfs-misc-fixes-for-3.19-2' into for-next
Conflicts:
	fs/xfs/xfs_iops.c
2014-12-04 09:46:17 +11:00
Brian Foster b29c70f598 xfs: split metadata and log buffer completion to separate workqueues
XFS traditionally sends all buffer I/O completion work to a single
workqueue. This includes metadata buffer completion and log buffer
completion. The log buffer completion requires a high priority queue to
prevent stalls due to log forces getting stuck behind other queued work.

Rather than continue to prioritize all buffer I/O completion due to the
needs of log completion, split log buffer completion off to
m_log_workqueue and move the high priority flag from m_buf_workqueue to
m_log_workqueue.

Add a b_ioend_wq wq pointer to xfs_buf to allow completion workqueue
customization on a per-buffer basis. Initialize b_ioend_wq to
m_buf_workqueue by default in the generic buffer I/O submission path.
Finally, override the default wq with the high priority m_log_workqueue
in the log buffer I/O submission path.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04 09:43:17 +11:00
Dave Chinner cdc9cec7c0 xfs: active inodes stat is broken
vn_active only ever gets decremented, so it has a very large
negative number.  Make it track the inode count we currently have
allocated properly so we can easily track the size of the inode
cache via tools like PCP.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-04 09:42:40 +11:00
Dave Chinner e77b8547ca Merge branch 'xfs-coccinelle-cleanups' into xfs-misc-fixes-for-3.19-2 2014-12-04 09:18:21 +11:00
Dave Chinner c14fc01340 Merge branch 'xfs-coccinelle-cleanups' into for-next 2014-12-01 09:03:02 +11:00
Markus Elfring d2a5e3c6fc xfs: remove unnecessary null checks
The functions xfs_blkdev_put() and xfs_qm_dqrele() test whether
their argument is NULL and then return immediately.  Thus the test
around the call is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-12-01 08:24:20 +11:00
Dave Chinner 216875a594 Merge branch 'xfs-consolidate-format-defs' into for-next 2014-11-28 14:52:16 +11:00
Christoph Hellwig 508b6b3b73 xfs: merge xfs_inum.h into xfs_format.h
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:27:10 +11:00
Christoph Hellwig 4fb6e8ade2 xfs: merge xfs_ag.h into xfs_format.h
More on-disk format consolidation.  A few declarations that weren't on-disk
format related move into better suitable spots.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:25:04 +11:00
Christoph Hellwig 6d3ebaae7c xfs: merge xfs_dinode.h into xfs_format.h
More consolidatation for the on-disk format defintions.  Note that the
XFS_IS_REALTIME_INODE moves to xfs_linux.h instead as it is not related
to the on disk format, but depends on a CONFIG_ option.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 14:24:06 +11:00
Brian Foster 78c931b8be xfs: replace global xfslogd wq with per-mount wq
The xfslogd workqueue is a global, single-job workqueue for buffer ioend
processing. This means we allow for a single work item at a time for all
possible XFS mounts on a system. fsstress testing in loopback XFS over
XFS configurations has reproduced xfslogd deadlocks due to the single
threaded nature of the queue and dependencies introduced between the
separate XFS instances by online discard (-o discard).

Discard over a loopback device converts the discard request to a hole
punch (fallocate) on the underlying file. Online discard requests are
issued synchronously and from xfslogd context in XFS, hence the xfslogd
workqueue is blocked in the upper fs waiting on a hole punch request to
be servied in the lower fs. If the lower fs issues I/O that depends on
xfslogd to complete, both filesystems end up hung indefinitely. This is
reproduced reliabily by generic/013 on XFS->loop->XFS test devices with
the '-o discard' mount option.

Further, docker implementations appear to use this kind of configuration
for container instance filesystems by default (container fs->dm->
loop->base fs) and therefore are subject to this deadlock when running
on XFS.

Replace the global xfslogd workqueue with a per-mount variant. This
guarantees each mount access to a single worker and prevents deadlocks
due to inter-fs dependencies introduced by discard. Since the queue is
only responsible for buffer iodone processing at this point in time,
rename xfslogd to xfs-buf.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2014-11-28 13:59:58 +11:00