Commit Graph

41239 Commits

Author SHA1 Message Date
Fabian Frederick b57c2cb9ea pagemap.h: move dir_pages() over there
That function was declared in a lot of filesystems to calculate
directory pages.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:02:00 -04:00
Al Viro e5e6e97fe0 remove the pointless include of lglock.h
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:02:00 -04:00
Rasmus Villemoes db6172c411 fs: cleanup slight list_entry abuse
list_entry is just a wrapper for container_of, but it is arguably
wrong (and slightly confusing) to use it when the pointed-to struct
member is not a struct list_head. Use container_of directly instead.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:59 -04:00
Al Viro 8ea3a7c0df Merge branch 'fscache-fixes' into for-next 2015-06-23 18:01:30 -04:00
Jan Kara a6de82cab1 xfs: Correctly lock inode when removing suid and file capabilities
Currently XFS calls file_remove_privs() without holding i_mutex. This is
wrong because that function can end up messing with file permissions and
file capabilities stored in xattrs for which we need i_mutex held.

Fix the problem by grabbing iolock exclusively when we will need to
change anything in permissions / xattrs.

Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:10 -04:00
Jan Kara 45f147a1bc fs: Call security_ops->inode_killpriv on truncate
Comment in include/linux/security.h says that ->inode_killpriv() should
be called when setuid bit is being removed and that similar security
labels (in fact this applies only to file capabilities) should be
removed at this time as well. However we don't call ->inode_killpriv()
when we remove suid bit on truncate.

We fix the problem by calling ->inode_need_killpriv() and subsequently
->inode_killpriv() on truncate the same way as we do it on file write.

After this patch there's only one user of should_remove_suid() - ocfs2 -
and indeed it's buggy because it doesn't call ->inode_killpriv() on
write. However fixing it is difficult because of special locking
constraints.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:09 -04:00
Jan Kara dbfae0cdcd fs: Provide function telling whether file_remove_privs() will do anything
Provide function telling whether file_remove_privs() will do anything.
Currently we only have should_remove_suid() and that does something
slightly different.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:09 -04:00
Jan Kara 5fa8e0a1c6 fs: Rename file_remove_suid() to file_remove_privs()
file_remove_suid() is a misnomer since it removes also file capabilities
stored in xattrs and sets S_NOSEC flag. Also should_remove_suid() tells
something else than whether file_remove_suid() call is necessary which
leads to bugs.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:08 -04:00
Jan Kara 2426f39100 fs: Fix S_NOSEC handling
file_remove_suid() could mistakenly set S_NOSEC inode bit when root was
modifying the file. As a result following writes to the file by ordinary
user would avoid clearing suid or sgid bits.

Fix the bug by checking actual mode bits before setting S_NOSEC.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:08 -04:00
Dan Carpenter c0c3a718e3 fs/posix_acl.c: make posix_acl_create() safer and cleaner
If posix_acl_create() returns an error code then "*acl" and "*default_acl"
can be uninitialized or point to freed memory.  This is a dangerous thing
to do.  For example, it causes a problem in ocfs2_reflink():

	fs/ocfs2/refcounttree.c:4327 ocfs2_reflink()
	error: potentially using uninitialized 'default_acl'.

I've re-written this so we set the pointers to NULL at the start.  I've
added a temporary "clone" variable to hold the value of "*acl" until end.
Setting them to NULL means means we don't need the "no_acl" label.  We may
as well remove the "apply_umask" stuff forward and remove that label as
well.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2015-06-23 18:01:07 -04:00
Al Viro 6b6dabc8dc nilfs2_direct_IO(): remove dead code
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:07 -04:00
Miklos Szeredi 2726d56620 vfs: add seq_file_path() helper
Turn
	seq_path(..., &file->f_path, ...);
into
	seq_file_path(..., file, ...);

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:01:07 -04:00
Miklos Szeredi 9bf39ab2ad vfs: add file_path() helper
Turn
	d_path(&file->f_path, ...);
into
	file_path(file, ...);

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-23 18:00:05 -04:00
Theodore Ts'o a2fd66d069 ext4: set lazytime on remount if MS_LAZYTIME is set by mount
Newer versions of mount parse the lazytime feature and pass it to the
mount system call via the flags field in the mount system call,
removing the lazytime string from the mount options list.  So we need
to check for the presence of MS_LAZYTIME and set it in sb->s_flags in
order for this flag to be set on a remount.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-06-23 11:03:54 -04:00
Chris Mason c40b7b064f Merge branch 'sysfs-fsdevices-4.2-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into anand 2015-06-23 05:34:39 -07:00
Linus Torvalds 43224b96af Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "A rather largish update for everything time and timer related:

   - Cache footprint optimizations for both hrtimers and timer wheel

   - Lower the NOHZ impact on systems which have NOHZ or timer migration
     disabled at runtime.

   - Optimize run time overhead of hrtimer interrupt by making the clock
     offset updates smarter

   - hrtimer cleanups and removal of restrictions to tackle some
     problems in sched/perf

   - Some more leap second tweaks

   - Another round of changes addressing the 2038 problem

   - First step to change the internals of clock event devices by
     introducing the necessary infrastructure

   - Allow constant folding for usecs/msecs_to_jiffies()

   - The usual pile of clockevent/clocksource driver updates

  The hrtimer changes contain updates to sched, perf and x86 as they
  depend on them plus changes all over the tree to cleanup API changes
  and redundant code, which got copied all over the place.  The y2038
  changes touch s390 to remove the last non 2038 safe code related to
  boot/persistant clock"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (114 commits)
  clocksource: Increase dependencies of timer-stm32 to limit build wreckage
  timer: Minimize nohz off overhead
  timer: Reduce timer migration overhead if disabled
  timer: Stats: Simplify the flags handling
  timer: Replace timer base by a cpu index
  timer: Use hlist for the timer wheel hash buckets
  timer: Remove FIFO "guarantee"
  timers: Sanitize catchup_timer_jiffies() usage
  hrtimer: Allow hrtimer::function() to free the timer
  seqcount: Introduce raw_write_seqcount_barrier()
  seqcount: Rename write_seqcount_barrier()
  hrtimer: Fix hrtimer_is_queued() hole
  hrtimer: Remove HRTIMER_STATE_MIGRATE
  selftest: Timers: Avoid signal deadlock in leap-a-day
  timekeeping: Copy the shadow-timekeeper over the real timekeeper last
  clockevents: Check state instead of mode in suspend/resume path
  selftests: timers: Add leap-second timer edge testing to leap-a-day.c
  ntp: Do leapsecond adjustment in adjtimex read path
  time: Prevent early expiry of hrtimers[CLOCK_REALTIME] at the leap second edge
  ntp: Introduce and use SECS_PER_DAY macro instead of 86400
  ...
2015-06-22 18:57:44 -07:00
Dave Chinner de50e16ffa Merge branch 'xfs-misc-fixes-for-4.2-3' into for-next 2015-06-23 08:49:01 +10:00
Dave Chinner 3d238b7e0e Merge branch 'xfs-freelist-cleanup' into for-next 2015-06-23 08:48:43 +10:00
Brian Foster f66bf04269 xfs: don't truncate attribute extents if no extents exist
The xfs_attr3_root_inactive() call from xfs_attr_inactive() assumes that
attribute blocks exist to invalidate. It is possible to have an
attribute fork without extents, however. Consider the case where the
attribute fork is created towards the beginning of xfs_attr_set() but
some part of the subsequent attribute set fails.

If an inode in such a state hits xfs_attr_inactive(), it eventually
calls xfs_dabuf_map() and possibly xfs_bmapi_read(). The former emits a
filesystem corruption warning, returns an error that bubbles back up to
xfs_attr_inactive(), and leads to destruction of the in-core attribute
fork without an on-disk reset. If the inode happens to make it back
through xfs_inactive() in this state (e.g., via a concurrent bulkstat
that cycles the inode from the reclaim state and releases it), i_afp
might not exist when xfs_bmapi_read() is called and causes a NULL
dereference panic.

A '-p 2' fsstress run to ENOSPC on a relatively small fs (1GB)
reproduces these problems. The behavior is a regression caused by:

6dfe5a0 xfs: xfs_attr_inactive leaves inconsistent attr fork state behind

... which removed logic that avoided the attribute extent truncate when
no extents exist. Restore this logic to ensure the attribute fork is
destroyed and reset correctly if it exists without any allocated
extents.

cc: stable@vger.kernel.org # 3.12 to 4.0.x
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-23 08:47:20 +10:00
Linus Torvalds 1bf7067c6e Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The main changes are:

   - 'qspinlock' support, enabled on x86: queued spinlocks - these are
     now the spinlock variant used by x86 as they outperform ticket
     spinlocks in every category.  (Waiman Long)

   - 'pvqspinlock' support on x86: paravirtualized variant of queued
     spinlocks.  (Waiman Long, Peter Zijlstra)

   - 'qrwlock' support, enabled on x86: queued rwlocks.  Similar to
     queued spinlocks, they are now the variant used by x86:

       CONFIG_ARCH_USE_QUEUED_SPINLOCKS=y
       CONFIG_QUEUED_SPINLOCKS=y
       CONFIG_ARCH_USE_QUEUED_RWLOCKS=y
       CONFIG_QUEUED_RWLOCKS=y

   - various lockdep fixlets

   - various locking primitives cleanups, further WRITE_ONCE()
     propagation"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  locking/lockdep: Remove hard coded array size dependency
  locking/qrwlock: Don't contend with readers when setting _QW_WAITING
  lockdep: Do not break user-visible string
  locking/arch: Rename set_mb() to smp_store_mb()
  locking/arch: Add WRITE_ONCE() to set_mb()
  rtmutex: Warn if trylock is called from hard/softirq context
  arch: Remove __ARCH_HAVE_CMPXCHG
  locking/rtmutex: Drop usage of __HAVE_ARCH_CMPXCHG
  locking/qrwlock: Rename QUEUE_RWLOCK to QUEUED_RWLOCKS
  locking/pvqspinlock: Rename QUEUED_SPINLOCK to QUEUED_SPINLOCKS
  locking/pvqspinlock: Replace xchg() by the more descriptive set_mb()
  locking/pvqspinlock, x86: Enable PV qspinlock for Xen
  locking/pvqspinlock, x86: Enable PV qspinlock for KVM
  locking/pvqspinlock, x86: Implement the paravirt qspinlock call patching
  locking/pvqspinlock: Implement simple paravirt support for the qspinlock
  locking/qspinlock: Revert to test-and-set on hypervisors
  locking/qspinlock: Use a simple write to grab the lock
  locking/qspinlock: Optimize for smaller NR_CPUS
  locking/qspinlock: Extract out code snippets for the next patch
  locking/qspinlock: Add pending bit
  ...
2015-06-22 14:54:22 -07:00
Linus Torvalds 052b398a43 Merge branch 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "In this pile: pathname resolution rewrite.

   - recursion in link_path_walk() is gone.

   - nesting limits on symlinks are gone (the only limit remaining is
     that the total amount of symlinks is no more than 40, no matter how
     nested).

   - "fast" (inline) symlinks are handled without leaving rcuwalk mode.

   - stack footprint (independent of the nesting) is below kilobyte now,
     about on par with what it used to be with one level of nested
     symlinks and ~2.8 times lower than it used to be in the worst case.

   - struct nameidata is entirely private to fs/namei.c now (not even
     opaque pointers are being passed around).

   - ->follow_link() and ->put_link() calling conventions had been
     changed; all in-tree filesystems converted, out-of-tree should be
     able to follow reasonably easily.

     For out-of-tree conversions, see Documentation/filesystems/porting
     for details (and in-tree filesystems for examples of conversion).

  That has sat in -next since mid-May, seems to survive all testing
  without regressions and merges clean with v4.1"

* 'for-linus-1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (131 commits)
  turn user_{path_at,path,lpath,path_dir}() into static inlines
  namei: move saved_nd pointer into struct nameidata
  inline user_path_create()
  inline user_path_parent()
  namei: trim do_last() arguments
  namei: stash dfd and name into nameidata
  namei: fold path_cleanup() into terminate_walk()
  namei: saner calling conventions for filename_parentat()
  namei: saner calling conventions for filename_create()
  namei: shift nameidata down into filename_parentat()
  namei: make filename_lookup() reject ERR_PTR() passed as name
  namei: shift nameidata inside filename_lookup()
  namei: move putname() call into filename_lookup()
  namei: pass the struct path to store the result down into path_lookupat()
  namei: uninline set_root{,_rcu}()
  namei: be careful with mountpoint crossings in follow_dotdot_rcu()
  Documentation: remove outdated information from automount-support.txt
  get rid of assorted nameidata-related debris
  lustre: kill unused helper
  lustre: kill unused macro (LOOKUP_CONTINUE)
  ...
2015-06-22 12:51:21 -07:00
Christoph Hellwig 68e8bb0334 nfsd: wrap too long lines in nfsd4_encode_read
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-22 14:15:05 -04:00
Christoph Hellwig 96bcad5064 nfsd: fput rd_file from XDR encode context
Remove the hack where we fput the read-specific file in generic code.
Instead we can do it in nfsd4_encode_read as that gets called for all
error cases as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-22 14:15:04 -04:00
Christoph Hellwig af90f707fa nfsd: take struct file setup fully into nfs4_preprocess_stateid_op
This patch changes nfs4_preprocess_stateid_op so it always returns
a valid struct file if it has been asked for that.  For that we
now allocate a temporary struct file for special stateids, and check
permissions if we got the file structure from the stateid.  This
ensures that all callers will get their handling of special stateids
right, and avoids code duplication.

There is a little wart in here because the read code needs to know
if we allocated a file structure so that it can copy around the
read-ahead parameters.  In the long run we should probably aim to
cache full file structures used with special stateids instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-22 14:15:03 -04:00
Trond Myklebust 1372a3130a Merge branch 'bugfixes'
* bugfixes:
  NFS: Ensure we set NFS_CONTEXT_RESEND_WRITES when requeuing writes
  pNFS: Fix a memory leak when attempted pnfs fails
  NFS: Ensure that we update the sequence id under the slot table lock
  nfs: Initialize cb_sequenceres information before validate_seqid()
  nfs: Only update callback sequnce id when CB_SEQUENCE success
  NFSv4: nfs4_handle_delegation_recall_error should ignore EAGAIN
2015-06-22 09:55:08 -04:00
Anand Jain f90fc54728 Btrfs: Check if kobject is initialized before put
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-06-22 14:43:31 +02:00
Miklos Szeredi cdb6727958 ovl: lookup whiteouts outside iterate_dir()
If jffs2 can deadlock on overlayfs readdir because it takes the same lock
on ->iterate() as in ->lookup().

Fix by moving whiteout checking outside iterate_dir().  Optimized by
collecting potential whiteouts (DT_CHR) in a temporary list and if
non-empty iterating throug these and checking for a 0/0 chardev.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Fixes: 49c21e1cac ("ovl: check whiteout while reading directory")
Reported-by: Roman Yeryomin <leroi.lists@gmail.com>
2015-06-22 13:53:48 +02:00
Miklos Szeredi 7c03b5d45b ovl: allow distributed fs as lower layer
Allow filesystems with .d_revalidate as lower layer(s), but not as upper
layer.

For local filesystems the rule was that modifications on the layers
directly while being part of the overlay results in undefined behavior.

This can easily be extended to distributed filesystems: we assume the tree
used as lower layer is static, which means ->d_revalidate() should always
return "1".  If that is not the case, return -ESTALE, don't try to work
around the modification.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-06-22 13:53:48 +02:00
Miklos Szeredi a6f15d9a75 ovl: don't traverse automount points
NFS and other distributed filesystems may place automount points in the
tree.  Previoulsy overlayfs refused to mount such filesystems types (based
on the existence of the .d_automount callback), even if the actual export
didn't have any automount points.

It cannot be determined in advance whether the filesystem has automount
points or not.  The solution is to allow fs with .d_automount but refuse to
traverse any automount points encountered.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-06-22 13:53:48 +02:00
Josef Bacik 3da40c7b08 ext4: only call ext4_truncate when size <= isize
At LSF we decided that if we truncate up from isize we shouldn't trim
fallocated blocks that were fallocated with KEEP_SIZE and are past the
new i_size.  This patch fixes ext4 to do this.

[ Completely reworked patch so that i_disksize would actually get set
  when truncating up.  Also reworked the code for handling truncate so
  that it's easier to handle. -- tytso ]

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Lukas Czerner <lczerner@redhat.com>
2015-06-22 00:31:26 -04:00
Eric Whitney 04e22412f4 ext4: make online defrag error reporting consistent
Make the error reporting behavior resulting from the unsupported use
of online defrag on files with data journaling enabled consistent with
that implemented for bigalloc file systems. Difference found with
ext4/308.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2015-06-21 21:38:03 -04:00
Eric Whitney c27e43a10c ext4: minor cleanup of ext4_da_reserve_space()
Remove outdated comments and dead code from ext4_da_reserve_space.
Clean up its trace point, and relocate it to make it more useful.

While we're at it, fix a nearby conditional used to determine if
we have a non-bigalloc file system.  It doesn't match usage elsewhere
in the code, and misleadingly suggests that an s_cluster_ratio value
of 0 would be legal.

Signed-off-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-21 21:37:05 -04:00
Darrick J. Wong 292db1bc6c ext4: don't retry file block mapping on bigalloc fs with non-extent file
ext4 isn't willing to map clusters to a non-extent file.  Don't signal
this with an out of space error, since the FS will retry the
allocation (which didn't fail) forever.  Instead, return EUCLEAN so
that the operation will fail immediately all the way back to userspace.

(The fix is either to run e2fsck -E bmap2extent, or to chattr +e the file.)

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-06-21 21:10:51 -04:00
Dave Chinner 496817b4be xfs: clean up XFS_MIN_FREELIST macros
We no longer calculate the minimum freelist size from the on-disk
AGF, so we don't need the macros used for this. That means the
nested macros can be cleaned up, and turn this into an actual
function so the logic is clear and concise. This will make it much
easier to add support for the rmap btree when the time comes.

This also gets rid of the XFS_AG_MAXLEVELS macro used by these
freelist macros as it is simply a wrapper around a single variable.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:13:30 +10:00
Dave Chinner 396503fc83 xfs: sanitise error handling in xfs_alloc_fix_freelist
The error handling is currently an inconsistent mess as every error
condition handles return values and releasing buffers individually.
Clean this up by using gotos and a sane error label stack.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:13:19 +10:00
Dave Chinner 72d552854b xfs: factor out free space extent length check
The longest extent length checks in xfs_alloc_fix_freelist() are now
essentially identical. Factor them out into a helper function, so we
know they are checking exactly the same thing before and after we
lock the AGF.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:04:42 +10:00
Dave Chinner 50adbcb4c4 xfs: xfs_alloc_fix_freelist() can use incore perag structures
At the moment, xfs_alloc_fix_freelist() uses a mix of per-ag based
access and agf buffer  based access to freelist and space usage
information. However, once the AGF buffer is locked inside this
function, it is guaranteed that both the in-memory and on-disk
values are identical. xfs_alloc_fix_freelist() doesn't modify the
values in the structures directly, so it is a read-only user of the
infomration, and hence can use the per-ag structure exclusively for
determining what it should do.

This opens up an avenue for cleaning up a lot of duplicated logic
whose only difference is the structure it gets the data from, and in
doing so removes a lot of needless byte swapping overhead when
fixing up the free list.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 10:04:31 +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 88ee2df7f2 xfs: return a void pointer from xfs_buf_offset
This avoids all kinds of unessecary casts in an envrionment like Linux where
we can assume that pointer arithmetics are support on void pointers.

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 09:44:29 +10:00
Christoph Hellwig fc51c2b5f8 xfs: remove inst_t
We can simply use a void pointer to pass a long return addresses in the
debugging helpers.

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 09:44:02 +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
Eric Sandeen 2ac56d3d4b xfs: fix remote symlinks on V5/CRC filesystems
If we create a CRC filesystem, mount it, and create a symlink with
a path long enough that it can't live in the inode, we get a very
strange result upon remount:

# ls -l mnt
total 4
lrwxrwxrwx. 1 root root 929 Jun 15 16:58 link -> XSLM

XSLM is the V5 symlink block header magic (which happens to be
followed by a NUL, so the string looks terminated).

xfs_readlink_bmap() advanced cur_chunk by the size of the header
for CRC filesystems, but never actually used that pointer; it
kept reading from bp->b_addr, which is the start of the block,
rather than the start of the symlink data after the header.

Looks like this problem goes back to v3.10.

Fixing this gets us reading the proper link target, again.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-22 09:42:48 +10:00
Theodore Ts'o c5e298ae53 ext4: prevent ext4_quota_write() from failing due to ENOSPC
In order to prevent quota block tracking to be inaccurate when
ext4_quota_write() fails with ENOSPC, we make two changes.  The quota
file can now use the reserved block (since the quota file is arguably
file system metadata), and ext4_quota_write() now uses
ext4_should_retry_alloc() to retry the block allocation after a commit
has completed and released some blocks for allocation.

This fixes failures of xfstests generic/270:

Quota error (device vdc): write_blk: dquota write failed
Quota error (device vdc): qtree_write_dquot: Error -28 occurred while creating quota

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-21 01:25:29 -04:00
Theodore Ts'o 89d96a6f8e ext4: call sync_blockdev() before invalidate_bdev() in put_super()
Normally all of the buffers will have been forced out to disk before
we call invalidate_bdev(), but there will be some cases, where a file
system operation was aborted due to an ext4_error(), where there may
still be some dirty buffers in the buffer cache for the device.  So
try to force them out to memory before calling invalidate_bdev().

This fixes a warning triggered by generic/081:

WARNING: CPU: 1 PID: 3473 at /usr/projects/linux/ext4/fs/block_dev.c:56 __blkdev_put+0xb5/0x16f()

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-06-20 22:50:33 -04:00
Jan Kara 2143c1965a jbd2: speedup jbd2_journal_dirty_metadata()
It is often the case that we mark buffer as having dirty metadata when
the buffer is already in that state (frequent for bitmaps, inode table
blocks, superblock). Thus it is unnecessary to contend on grabbing
journal head reference and bh_state lock. Avoid that by checking whether
any modification to the buffer is needed before grabbing any locks or
references.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-20 21:44:17 -04:00
Christoph Hellwig a0649b2d3f nfsd: refactor nfs4_preprocess_stateid_op
Split out two self contained helpers to make the function more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-19 15:39:52 -04:00
Christoph Hellwig e749a4621e nfsd: clean up raparams handling
Refactor the raparam hash helpers to just deal with the raparms,
and keep opening/closing files separate from that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-19 15:39:51 -04:00
Fabian Frederick 97b1f9aae9 nfsd: use swap() in sort_pacl_range()
Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-19 15:39:50 -04:00
Bob Peterson 39b0f1e929 GFS2: Don't brelse rgrp buffer_heads every allocation
This patch allows the block allocation code to retain the buffers
for the resource groups so they don't need to be re-read from buffer
cache with every request. This is a performance improvement that's
especially noticeable when resource groups are very large. For
example, with 2GB resource groups and 4K blocks, there can be 33
blocks for every resource group. This patch allows those 33 buffers
to be kept around and not read in and thrown away with every
operation. The buffers are released when the resource group is
either synced or invalidated.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Reviewed-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>
2015-06-19 07:40:22 -05:00
Anand Jain d2ff1b2008 Btrfs: sysfs: add support to show replacing target in the sysfs
This patch will add support to show the replacing target in sysfs
during the process of replacement.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
2015-06-19 14:03:54 +02:00
Anand Jain 4fde46f0cc Btrfs: free the stale device
When btrfs on a device is overwritten with a new btrfs (mkfs),
the old btrfs instance in the kernel becomes stale. So with this
patch, if kernel finds device is overwritten then delete the stale
fsid/uuid.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
2015-06-19 14:03:13 +02:00
David Howells 4bacc9c923 overlayfs: Make f_path always point to the overlay and f_inode to the underlay
Make file->f_path always point to the overlay dentry so that the path in
/proc/pid/fd is correct and to ensure that label-based LSMs have access to the
overlay as well as the underlay (path-based LSMs probably don't need it).

Using my union testsuite to set things up, before the patch I see:

	[root@andromeda union-testsuite]# bash 5</mnt/a/foo107
	[root@andromeda union-testsuite]# ls -l /proc/$$/fd/
	...
	lr-x------. 1 root root 64 Jun  5 14:38 5 -> /a/foo107
	[root@andromeda union-testsuite]# stat /mnt/a/foo107
	...
	Device: 23h/35d Inode: 13381       Links: 1
	...
	[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
	...
	Device: 23h/35d Inode: 13381       Links: 1
	...

After the patch:

	[root@andromeda union-testsuite]# bash 5</mnt/a/foo107
	[root@andromeda union-testsuite]# ls -l /proc/$$/fd/
	...
	lr-x------. 1 root root 64 Jun  5 14:22 5 -> /mnt/a/foo107
	[root@andromeda union-testsuite]# stat /mnt/a/foo107
	...
	Device: 23h/35d Inode: 40346       Links: 1
	...
	[root@andromeda union-testsuite]# stat -L /proc/$$/fd/5
	...
	Device: 23h/35d Inode: 40346       Links: 1
	...

Note the change in where /proc/$$/fd/5 points to in the ls command.  It was
pointing to /a/foo107 (which doesn't exist) and now points to /mnt/a/foo107
(which is correct).

The inode accessed, however, is the lower layer.  The union layer is on device
25h/37d and the upper layer on 24h/36d.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-19 03:19:32 -04:00
David Howells f25801ee46 overlay: Call ovl_drop_write() earlier in ovl_dentry_open()
Call ovl_drop_write() earlier in ovl_dentry_open() before we call vfs_open()
as we've done the copy up for which we needed the freeze-write lock by that
point.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-19 03:19:31 -04:00
Peter Zijlstra a7c6f571ff seqcount: Rename write_seqcount_barrier()
I'll shortly be introducing another seqcount primitive that's useful
to provide ordering semantics and would like to use the
write_seqcount_barrier() name for that.

Seeing how there's only one user of the current primitive, lets rename
it to invalidate, as that appears what its doing.

While there, employ lockdep_assert_held() instead of
assert_spin_locked() to not generate debug code for regular kernels.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: ktkhai@parallels.com
Cc: rostedt@goodmis.org
Cc: juri.lelli@gmail.com
Cc: pang.xunlei@linaro.org
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: wanpeng.li@linux.intel.com
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: umgwanakikbuti@gmail.com
Link: http://lkml.kernel.org/r/20150611124743.279926217@infradead.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-06-19 00:09:56 +02:00
Tejun Heo fb02915f47 kernfs: make kernfs_get_inode() public
Move kernfs_get_inode() prototype from fs/kernfs/kernfs-internal.h to
include/linux/kernfs.h.  It obtains the matching inode for a
kernfs_node.

It will be used by cgroup for inode based permission checks for now
but is generally useful.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-18 16:54:28 -04:00
Bob Peterson e7ccaf5fe1 GFS2: Don't add all glocks to the lru
The glocks used for resource groups often come and go hundreds of
thousands of times per second. Adding them to the lru list just
adds unnecessary contention for the lru_lock spin_lock, especially
considering we're almost certainly going to re-use the glock and
take it back off the lru microseconds later. We never want the
glock shrinker to cull them anyway. This patch adds a new bit in
the glops that determines which glock types get put onto the lru
list and which ones don't.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-06-18 12:17:59 -05:00
Yijing Wang dfad7000f3 nfs: Fix comment for nfs_pageio_init() and nfs_pageio_complete_mirror()
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-18 08:59:13 -04:00
Trond Myklebust c70701131f NFS: Ensure we set NFS_CONTEXT_RESEND_WRITES when requeuing writes
If a write attempt fails, and the write is queued up for resending to
the server, as opposed to being dropped, then we need to set the
appropriate flag so that nfs_file_fsync() does the right thing.

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-17 20:00:42 -04:00
Trond Myklebust 1ca018d28d pNFS: Fix a memory leak when attempted pnfs fails
pnfs_do_write() expects the call to pnfs_write_through_mds() to free the
pgio header and to release the layout segment before exiting. The problem
is that nfs_pgio_data_destroy() doesn't actually do this; it only frees
the memory allocated by nfs_generic_pgio().

Ditto for pnfs_do_read()...

Fix in both cases is to add a call to hdr->release(hdr).

Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-17 20:00:26 -04:00
Tejun Heo 46b15caa7c vfs, writeback: replace FS_CGROUP_WRITEBACK with SB_I_CGROUPWB
FS_CGROUP_WRITEBACK indicates whether a file_system_type supports
cgroup writeback; however, different super_blocks of the same
file_system_type may or may not support cgroup writeback depending on
filesystem options.  This patch replaces FS_CGROUP_WRITEBACK with a
per-super_block flag.

super_block->s_flags carries some internal flags in the high bits but
it's exposd to userland through uapi header and running out of space
anyway.  This patch adds a new field super_block->s_iflags to carry
kernel-internal flags.  It is currently only used by the new
SB_I_CGROUPWB flag whose concatenated and abbreviated name is for
consistency with other super_block flags.

ext2_fill_super() is updated to set SB_I_CGROUPWB.

v2: Added super_block->s_iflags instead of stealing another high bit
    from sb->s_flags as suggested by Christoph and Jan.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-ext4@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-17 12:47:39 -06:00
Tejun Heo dd73e4b7df writeback: do foreign inode detection iff cgroup writeback is enabled
Currently, even when a filesystem doesn't set the FS_CGROUP_WRITEBACK
flag, if the filesystem uses wbc_init_bio() and wbc_account_io(), the
foreign inode detection and migration logic still ends up activating
cgroup writeback which is unexpected.  This patch ensures that the
foreign inode detection logic stays disabled when inode_cgwb_enabled()
is false by not associating writeback_control's with bdi_writeback's.

This also avoids unnecessary operations in wbc_init_bio(),
wbc_account_io() and wbc_detach_inode() for filesystems which don't
support cgroup writeback.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-17 12:47:37 -06:00
Al Viro 4ef51e8b7a Merge branch 'for-linus' into for-next 2015-06-17 14:44:05 -04:00
Fabian Frederick e4f95517f1 fs/ufs: restore s_lock mutex_init()
Add last missing line in commit "cdd9eefdf905"
("fs/ufs: restore s_lock mutex")

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-17 14:43:02 -04:00
Paul Gortmaker c013d5a458 fs/notify: don't use module_init for non-modular inotify_user code
The INOTIFY_USER option is bool, and hence this code is either
present or absent.  It will never be modular, so using
module_init as an alias for __initcall is rather misleading.

Fix this up now, so that we can relocate module_init from
init.h into module.h in the future.  If we don't do this, we'd
have to add module.h to obviously non-modular code, and that
would be a worse thing.

Note that direct use of __initcall is discouraged, vs. one
of the priority categorized subgroups.  As __initcall gets
mapped onto device_initcall, our use of fs_initcall (which
makes sense for fs code) will thus change this registration
from level 6-device to level 5-fs (i.e. slightly earlier).
However no observable impact of that small difference has
been observed during testing, or is expected.

Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2015-06-16 14:12:34 -04:00
Trond Myklebust 3438995bc4 NFS: NFSoRDMA Client Changes
These patches continue to build up for improving the rsize and wsize that the
 NFS client uses when talking over RDMA.  In addition, these patches also add
 in scalability enhancements and other bugfixes.
 
 Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
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Merge tag 'nfs-rdma-for-4.2' of git://git.linux-nfs.org/projects/anna/nfs-rdma

NFS: NFSoRDMA Client Changes

These patches continue to build up for improving the rsize and wsize that the
NFS client uses when talking over RDMA.  In addition, these patches also add
in scalability enhancements and other bugfixes.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

* tag 'nfs-rdma-for-4.2' of git://git.linux-nfs.org/projects/anna/nfs-rdma: (142 commits)
  xprtrdma: Reduce per-transport MR allocation
  xprtrdma: Stack relief in fmr_op_map()
  xprtrdma: Split rb_lock
  xprtrdma: Remove rpcrdma_ia::ri_memreg_strategy
  xprtrdma: Remove ->ro_reset
  xprtrdma: Remove unused LOCAL_INV recovery logic
  xprtrdma: Acquire MRs in rpcrdma_register_external()
  xprtrdma: Introduce an FRMR recovery workqueue
  xprtrdma: Acquire FMRs in rpcrdma_fmr_register_external()
  xprtrdma: Introduce helpers for allocating MWs
  xprtrdma: Use ib_device pointer safely
  xprtrdma: Remove rr_func
  xprtrdma: Replace rpcrdma_rep::rr_buffer with rr_rxprt
  xprtrdma: Warn when there are orphaned IB objects
  ...
2015-06-16 11:37:50 -04:00
Trond Myklebust 5ba12443a1 NFSv4: Fix stateid recovery on revoked delegations
Ensure that we fix the non-NULL stateid case as well.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:29:51 -04:00
Olga Kornievskaia ae2ffef383 Recover from stateid-type error on SETATTR
Client can receives stateid-type error (eg., BAD_STATEID) on SETATTR when
delegation stateid was used. When no open state exists, in case of application
calling truncate() on the file, client has no state to recover and fails with
EIO.

Instead, upon such error, return the bad delegation and then resend the
SETATTR with a zero stateid.

Signed-off: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:29:46 -04:00
Kinglong Mee df05a49f72 nfs: Fix showing truncated fsid/dev in, /proc/net/nfsfs/volumes
A truncated fsid showing from /proc/fs/nfsfs/volumes as,
NV SERVER   PORT DEV     FSID              FSC
v4 c0a80881  801 0:43    34931f044c2a439b  no

It should be as,
NV SERVER   PORT DEV          FSID                              FSC
v4 c0a80881  801 0:43         34931f044c2a439b:954c5d830fa4be8c no

The max buffer length for storing "%llx:%llx" format should be
 16 + 1 + 16 + 1 = 34 (16 for %llx, 1 for ':', 1 for '\0').

Also, for storing "%u:%u" of MAJOR() and MINOR() should be
 8 + 1 + 3 + 1 = 13 (8 for 2^24, 1 for ':', 3 for 2^8, 1 for '\0').

v2, add comments for dev/fsid buffer and use sizeof in snprintf.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:17:37 -04:00
Jeff Layton 873e385116 nfs: make nfs4_init_uniform_client_string use a dynamically allocated buffer
Change the uniform client string generator to dynamically allocate the
NFSv4 client name string buffer. With this patch, we can eliminate the
buffers that are embedded within the "args" structs and simply use the
name string that is hanging off the client.

This uniform string case is a little simpler than the nonuniform since
we don't need to deal with RCU, but we do have two different cases,
depending on whether there is a uniquifier or not.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:15:51 -04:00
Jeff Layton a319268891 nfs: make nfs4_init_nonuniform_client_string use a dynamically allocated buffer
The way the *_client_string functions work is a little goofy. They build
the string in an on-stack buffer and then use kstrdup to copy it. This
is not only stack-heavy but artificially limits the size of the client
name string. Change it so that we determine the length of the string,
allocate it and then scnprintf into it.

Since the contents of the nonuniform string depend on rcu-managed data
structures, it's possible that they'll change between when we allocate
the string and when we go to fill it. If that happens, free the string,
recalculate the length and try again. If it the mismatch isn't resolved
on the second try then just give up and return -EINVAL.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:15:45 -04:00
Jeff Layton b8fb2f595e nfs: update maxsz values for SETCLIENTID and EXCHANGE_ID
The spec allows for up to NFS4_OPAQUE_LIMIT (1k). While we'll almost
certainly never use that much, these ops are generally the only ones
in the compound so we might as well allow for them to be that large.

Also, the existing code didn't add in a word for the opaque length
field for either name string. Fix that while we're in there.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:15:40 -04:00
Jeff Layton 3a6bb73879 nfs: convert setclientid and exchange_id encoders to use clp->cl_owner_id
...instead of buffers that are part of their arg structs. We already
hold a reference to the client, so we might as well use the allocated
buffer. In the event that we can't allocate the clp->cl_owner_id, then
just return -ENOMEM.

Note too that we switch from a GFP_KERNEL allocation here to GFP_NOFS.
It's possible we could end up trying to do a SETCLIENTID or EXCHANGE_ID
in order to reclaim some memory, and the GFP_KERNEL allocations in the
existing code could cause recursion back into NFS reclaim.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:15:31 -04:00
Fabian Frederick 455b6ee645 pnfs/flexfiles: use swap() in ff_layout_sort_mirrors()
Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-16 11:14:03 -04:00
Al Viro 70d45cdb66 ufs: don't touch mtime/ctime of directory being moved
See "ext2: Do not update mtime of a moved directory" (and followup in
"ext2: fix unbalanced kmap()/kunmap()") for background; this is UFS
equivalent - the same problem exists here.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16 02:08:34 -04:00
Al Viro a50e4a02ad ufs: don't bother with lock_ufs()/unlock_ufs() for directory access
We are already serialized by ->i_mutex and operations on different
directories are independent.  These calls are just rudiments of
blind BKL conversion and they should've been removed back then.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16 02:08:31 -04:00
Jan Kara 514d748f69 ufs: Fix possible deadlock when looking up directories
Commit e4502c63f5 (ufs: deal with nfsd/iget races) made ufs
create inodes with I_NEW flag set. However ufs_mkdir() never cleared
this flag. Thus if someone ever tried to lookup the directory by inode
number, he would deadlock waiting for I_NEW to be cleared. Luckily this
mostly happens only if the filesystem is exported over NFS since
otherwise we have the inode attached to dentry and don't look it up by
inode number. In rare cases dentry can get freed without inode being
freed and then we'd hit the deadlock even without NFS export.

Fix the problem by clearing I_NEW before instantiating new directory
inode.

Fixes: e4502c63f5
Reported-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16 02:08:12 -04:00
Jan Kara 12ecbb4b1d ufs: Fix warning from unlock_new_inode()
Commit e4502c63f5 (ufs: deal with nfsd/iget races) introduced
unlock_new_inode() call into ufs_add_nondir(). However that function
gets called also from ufs_link() which hands it already initialized
inode and thus unlock_new_inode() complains. The problem is harmless but
annoying.

Fix the problem by opencoding necessary stuff in ufs_link()

Fixes: e4502c63f5
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16 02:08:07 -04:00
Fabian Frederick cdd9eefdf9 fs/ufs: restore s_lock mutex
Commit 0244756edc ("ufs: sb mutex merge + mutex_destroy") generated
deadlocks in read/write mode on mkdir.

This patch partially reverts it keeping fixes by Andrew Morton and
mutex_destroy()

[AV: fixed a missing bit in ufs_remount()]

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reported-by: Ian Campbell <ian.campbell@citrix.com>
Suggested-by: Jan Kara <jack@suse.cz>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Roger Pau Monne <roger.pau@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-16 02:07:38 -04:00
Michal Hocko 7b506b1035 jbd2: get rid of open coded allocation retry loop
insert_revoke_hash does an open coded endless allocation loop if
journal_oom_retry is true. It doesn't implement any allocation fallback
strategy between the retries, though. The memory allocator doesn't know
about the never fail requirement so it cannot potentially help to move
on with the allocation (e.g. use memory reserves).

Get rid of the retry loop and use __GFP_NOFAIL instead. We will lose the
debugging message but I am not sure it is anyhow helpful.

Do the same for journal_alloc_journal_head which is doing a similar
thing.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-15 15:45:58 -04:00
Andreas Dilger b03a2f7eb2 ext4: improve warning directory handling messages
Several ext4_warning() messages in the directory handling code do not
report the inode number of the (potentially corrupt) directory where a
problem is seen, and others report this in an ad-hoc manner.  Add an
ext4_warning_inode() helper to print the inode number and command name
consistent with ext4_error_inode().

Consolidate the place in ext4.h that these macros are defined.

Clean up some other directory error and warning messages to print the
calling function name.

Minor code style fixes in nearby lines.

Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-15 14:50:26 -04:00
Joseph Qi 6f6a6fda29 jbd2: fix ocfs2 corrupt when updating journal superblock fails
If updating journal superblock fails after journal data has been
flushed, the error is omitted and this will mislead the caller as a
normal case.  In ocfs2, the checkpoint will be treated successfully
and the other node can get the lock to update. Since the sb_start is
still pointing to the old log block, it will rewrite the journal data
during journal recovery by the other node. Thus the new updates will
be overwritten and ocfs2 corrupts.  So in above case we have to return
the error, and ocfs2_commit_cache will take care of the error and
prevent the other node to do update first.  And only after recovering
journal it can do the new updates.

The issue discussion mail can be found at:
https://oss.oracle.com/pipermail/ocfs2-devel/2015-June/010856.html
http://comments.gmane.org/gmane.comp.file-systems.ext4/48841

[ Fixed bug in patch which allowed a non-negative error return from
  jbd2_cleanup_journal_tail() to leak out of jbd2_fjournal_flush(); this
  was causing xfstests ext4/306 to fail. -- Ted ]

Reported-by: Yiwen Jiang <jiangyiwen@huawei.com>
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Tested-by: Yiwen Jiang <jiangyiwen@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: stable@vger.kernel.org
2015-06-15 14:36:01 -04:00
Rasmus Villemoes 97b4af2f76 ext4: mballoc: avoid 20-argument function call
Making a function call with 20 arguments is rather expensive in both
stack and .text. In this case, doing the formatting manually doesn't
make it any less readable, so we might as well save 155 bytes of .text
and 112 bytes of stack.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
2015-06-15 00:32:58 -04:00
Lukas Czerner 0d306dcf86 ext4: wait for existing dio workers in ext4_alloc_file_blocks()
Currently existing dio workers can jump in and potentially increase
extent tree depth while we're allocating blocks in
ext4_alloc_file_blocks().  This may cause us to underestimate the
number of credits needed for the transaction because the extent tree
depth can change after our estimation.

Fix this by waiting for all the existing dio workers in the same way
as we do it in ext4_punch_hole.  We've seen errors caused by this in
xfstest generic/299, however it's really hard to reproduce.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-15 00:23:53 -04:00
Lukas Czerner 4134f5c88d ext4: recalculate journal credits as inode depth changes
Currently in ext4_alloc_file_blocks() the number of credits is
calculated only once before we enter the allocation loop. However within
the allocation loop the extent tree depth can change, hence the number
of credits needed can increase potentially exceeding the number of credits
reserved in the handle which can cause journal failures.

Fix this by recalculating number of credits when the inode depth
changes. Note that even though ext4_alloc_file_blocks() is only
currently used by extent base inodes we will avoid recalculating number
of credits unnecessarily in the case of indirect based inodes.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-15 00:20:46 -04:00
Dmitry Monakhov b4f1afcd06 jbd2: use GFP_NOFS in jbd2_cleanup_journal_tail()
jbd2_cleanup_journal_tail() can be invoked by jbd2__journal_start()
So allocations should be done with GFP_NOFS

[Full stack trace snipped from 3.10-rh7]
[<ffffffff815c4bd4>] dump_stack+0x19/0x1b
[<ffffffff8105dba1>] warn_slowpath_common+0x61/0x80
[<ffffffff8105dcca>] warn_slowpath_null+0x1a/0x20
[<ffffffff815c2142>] slab_pre_alloc_hook.isra.31.part.32+0x15/0x17
[<ffffffff8119c045>] kmem_cache_alloc+0x55/0x210
[<ffffffff811477f5>] ? mempool_alloc_slab+0x15/0x20
[<ffffffff811477f5>] mempool_alloc_slab+0x15/0x20
[<ffffffff81147939>] mempool_alloc+0x69/0x170
[<ffffffff815cb69e>] ? _raw_spin_unlock_irq+0xe/0x20
[<ffffffff8109160d>] ? finish_task_switch+0x5d/0x150
[<ffffffff811f1a8e>] bio_alloc_bioset+0x1be/0x2e0
[<ffffffff8127ee49>] blkdev_issue_flush+0x99/0x120
[<ffffffffa019a733>] jbd2_cleanup_journal_tail+0x93/0xa0 [jbd2] -->GFP_KERNEL
[<ffffffffa019aca1>] jbd2_log_do_checkpoint+0x221/0x4a0 [jbd2]
[<ffffffffa019afc7>] __jbd2_log_wait_for_space+0xa7/0x1e0 [jbd2]
[<ffffffffa01952d8>] start_this_handle+0x2d8/0x550 [jbd2]
[<ffffffff811b02a9>] ? __memcg_kmem_put_cache+0x29/0x30
[<ffffffff8119c120>] ? kmem_cache_alloc+0x130/0x210
[<ffffffffa019573a>] jbd2__journal_start+0xba/0x190 [jbd2]
[<ffffffff811532ce>] ? lru_cache_add+0xe/0x10
[<ffffffffa01c9549>] ? ext4_da_write_begin+0xf9/0x330 [ext4]
[<ffffffffa01f2c77>] __ext4_journal_start_sb+0x77/0x160 [ext4]
[<ffffffffa01c9549>] ext4_da_write_begin+0xf9/0x330 [ext4]
[<ffffffff811446ec>] generic_file_buffered_write_iter+0x10c/0x270
[<ffffffff81146918>] __generic_file_write_iter+0x178/0x390
[<ffffffff81146c6b>] __generic_file_aio_write+0x8b/0xb0
[<ffffffff81146ced>] generic_file_aio_write+0x5d/0xc0
[<ffffffffa01bf289>] ext4_file_write+0xa9/0x450 [ext4]
[<ffffffff811c31d9>] ? pipe_read+0x379/0x4f0
[<ffffffff811b93f0>] do_sync_write+0x90/0xe0
[<ffffffff811b9b6d>] vfs_write+0xbd/0x1e0
[<ffffffff811ba5b8>] SyS_write+0x58/0xb0
[<ffffffff815d4799>] system_call_fastpath+0x16/0x1b

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-06-15 00:18:02 -04:00
Fabian Frederick 13b987ea27 fs/ufs: revert "ufs: fix deadlocks introduced by sb mutex merge"
This reverts commit 9ef7db7f38 ("ufs: fix deadlocks introduced by sb
mutex merge") That patch tried to solve commit 0244756edc ("ufs: sb
mutex merge + mutex_destroy") which is itself partially reverted due to
multiple deadlocks.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Suggested-by: Jan Kara <jack@suse.cz>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: Roger Pau Monne <roger.pau@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2015-06-14 11:31:51 -04:00
Al Viro 3f4a949410 ncpfs: successful rename() should invalidate caches for parents
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-06-14 11:31:39 -04:00
Fabian Frederick bf86546760 ext4: use swap() in mext_page_double_lock()
Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-12 23:47:33 -04:00
Fabian Frederick 4b7e2db5c0 ext4: use swap() in memswap()
Use kernel.h macro definition.

Thanks to Julia Lawall for Coccinelle scripting support.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-12 23:46:33 -04:00
Theodore Ts'o bdf96838ae ext4: fix race between truncate and __ext4_journalled_writepage()
The commit cf108bca465d: "ext4: Invert the locking order of page_lock
and transaction start" caused __ext4_journalled_writepage() to drop
the page lock before the page was written back, as part of changing
the locking order to jbd2_journal_start -> page_lock.  However, this
introduced a potential race if there was a truncate racing with the
data=journalled writeback mode.

Fix this by grabbing the page lock after starting the journal handle,
and then checking to see if page had gotten truncated out from under
us.

This fixes a number of different warnings or BUG_ON's when running
xfstests generic/086 in data=journalled mode, including:

jbd2_journal_dirty_metadata: vdc-8: bad jh for block 115643: transaction (ee3fe7
c0, 164), jh->b_transaction (  (null), 0), jh->b_next_transaction (  (null), 0), jlist 0

	      	      	  - and -

kernel BUG at /usr/projects/linux/ext4/fs/jbd2/transaction.c:2200!
    ...
Call Trace:
 [<c02b2ded>] ? __ext4_journalled_invalidatepage+0x117/0x117
 [<c02b2de5>] __ext4_journalled_invalidatepage+0x10f/0x117
 [<c02b2ded>] ? __ext4_journalled_invalidatepage+0x117/0x117
 [<c027d883>] ? lock_buffer+0x36/0x36
 [<c02b2dfa>] ext4_journalled_invalidatepage+0xd/0x22
 [<c0229139>] do_invalidatepage+0x22/0x26
 [<c0229198>] truncate_inode_page+0x5b/0x85
 [<c022934b>] truncate_inode_pages_range+0x156/0x38c
 [<c0229592>] truncate_inode_pages+0x11/0x15
 [<c022962d>] truncate_pagecache+0x55/0x71
 [<c02b913b>] ext4_setattr+0x4a9/0x560
 [<c01ca542>] ? current_kernel_time+0x10/0x44
 [<c026c4d8>] notify_change+0x1c7/0x2be
 [<c0256a00>] do_truncate+0x65/0x85
 [<c0226f31>] ? file_ra_state_init+0x12/0x29

	      	      	  - and -

WARNING: CPU: 1 PID: 1331 at /usr/projects/linux/ext4/fs/jbd2/transaction.c:1396
irty_metadata+0x14a/0x1ae()
    ...
Call Trace:
 [<c01b879f>] ? console_unlock+0x3a1/0x3ce
 [<c082cbb4>] dump_stack+0x48/0x60
 [<c0178b65>] warn_slowpath_common+0x89/0xa0
 [<c02ef2cf>] ? jbd2_journal_dirty_metadata+0x14a/0x1ae
 [<c0178bef>] warn_slowpath_null+0x14/0x18
 [<c02ef2cf>] jbd2_journal_dirty_metadata+0x14a/0x1ae
 [<c02d8615>] __ext4_handle_dirty_metadata+0xd4/0x19d
 [<c02b2f44>] write_end_fn+0x40/0x53
 [<c02b4a16>] ext4_walk_page_buffers+0x4e/0x6a
 [<c02b59e7>] ext4_writepage+0x354/0x3b8
 [<c02b2f04>] ? mpage_release_unused_pages+0xd4/0xd4
 [<c02b1b21>] ? wait_on_buffer+0x2c/0x2c
 [<c02b5a4b>] ? ext4_writepage+0x3b8/0x3b8
 [<c02b5a5b>] __writepage+0x10/0x2e
 [<c0225956>] write_cache_pages+0x22d/0x32c
 [<c02b5a4b>] ? ext4_writepage+0x3b8/0x3b8
 [<c02b6ee8>] ext4_writepages+0x102/0x607
 [<c019adfe>] ? sched_clock_local+0x10/0x10e
 [<c01a8a7c>] ? __lock_is_held+0x2e/0x44
 [<c01a8ad5>] ? lock_is_held+0x43/0x51
 [<c0226dff>] do_writepages+0x1c/0x29
 [<c0276bed>] __writeback_single_inode+0xc3/0x545
 [<c0277c07>] writeback_sb_inodes+0x21f/0x36d
    ...

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-06-12 23:45:33 -04:00
Theodore Ts'o 1cb767cd4a ext4 crypto: fail the mount if blocksize != pagesize
We currently don't correctly handle the case where blocksize !=
pagesize, so disallow the mount in those cases.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-12 23:44:33 -04:00
Josef Bacik 37b8d27de5 Btrfs: use received_uuid of parent during send
Neil Horman pointed out a problem where if he did something like this

receive A
snap A B
change B
send -p A B

and then on another box do

recieve A
receive B

the receive B would fail because we use the UUID of A for the clone sources for
B.  This makes sense most of the time because normally you are sending from the
original sources, not a received source.  However when you use a recieved subvol
its UUID is going to be something completely different, so if you then try to
receive the diff on a different volume it won't find the UUID because the new A
will be something else.  The only constant is the received uuid.  So instead
check to see if we have received_uuid set on the root, and if so use that as the
clone source, as btrfs receive looks for matches either in received_uuid or
uuid.  Thanks,

Reported-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-12 13:20:38 -07:00
Liu Bo 0eeff2362b Btrfs: fix use-after-free in btrfs_replay_log
@log_root_tree should not be referenced after kfree.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-12 11:03:21 -07:00
Chao Yu 3c45414527 f2fs: do not trim preallocated blocks when truncating after i_size
When we perform generic/092 in xfstests, output is like below:

     XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
     0: [0..10239]: data
     0: [0..10239]: data
    -1: [10240..20479]: unwritten
    +1: [10240..14335]: unwritten

This is because with this testcase, we redefine the regulation for
truncate in perallocated space past i_size as below:

"There was some confused about what the fs was supposed to do when you
truncate at i_size with preallocated space past i_size. We decided on the
following things.

1) truncate(i_size) will trim all blocks past i_size.
2) truncate(x) where x > i_size will not trim all blocks past i_size.
"

This method is used in xfs, and then ext4/btrfs will follow the rule.

This patch fixes to follow the new rule for f2fs.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-11 18:30:49 -07:00
Trond Myklebust 4e54ab8d8c NFS: Ensure that we update the sequence id under the slot table lock
Fix a callback slot table regression.

Fixes: e937ee714b ("nfs: Only update callback sequnce id when CB_SEQUENCE success")
Cc: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-11 21:15:52 -04:00
Kinglong Mee 0579c8d208 nfs: Initialize cb_sequenceres information before validate_seqid()
For a cb_layoutrecall replay, nfsd got CB_SEQUENCE status of zero,
but all informations of cb_sequenceres are zero too !!!

validate_seqid() return NFS4ERR_RETRY_UNCACHED_REP for a replay,
and skip the initlize cb_sequenceres.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-11 21:09:06 -04:00
Jaegeuk Kim 43f54cd52f f2fs crypto: add alloc_bounce_page
This patch adds alloc_bounce_page likewise ext4.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-11 15:04:20 -07:00
Jaegeuk Kim 7e8e754a4b f2fs crypto: fix to handle errors likewise ext4
This patch makes some error handling policies same with ext4.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-11 15:00:36 -07:00
Jeff Layton 6f02dc88be nfs: deny backchannel RPCs with an incorrect authflavor instead of dropping them
A drop should really only be done when the frame is malformed or we have
reason to think that there is some sort of DoS going on. When we get an
RPC with bad auth, we should send back an error instead.

Cc: Andy Adamson <William.Adamson@netapp.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-11 14:06:34 -04:00
Kinglong Mee e937ee714b nfs: Only update callback sequnce id when CB_SEQUENCE success
When testing pnfs layout, nfsd got error NFS4ERR_SEQ_MISORDERED.
It is caused by nfs return NFS4ERR_DELAY before validate_seqid(),
don't update the sequnce id, but nfsd updates the sequnce id !!!

According to RFC5661 20.9.3,
" If CB_SEQUENCE returns an error, then the state of the slot
  (sequence ID, cached reply) MUST NOT change. "

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-11 14:00:40 -04:00
Vaishali Thakkar 4ed0d83d05 NFS: Convert use of __constant_htonl to htonl
In little endian cases, the macro htonl unfolds to __swab32 which
provides special case for constants. In big endian cases,
__constant_htonl and htonl expand directly to the same expression.
So, replace __constant_htonl with htonl with the goal of getting
rid of the definition of __constant_htonl completely.

The semantic patch that performs this transformation is as follows:

@@expression x;@@

- __constant_htonl(x)
+ htonl(x)

Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:57:59 -04:00
Anna Schumaker 11598b8ff2 NFS: Remove unused nfs_rw_ops->rw_release() function
This was only ever set to nfs_writeback_release_common(), a function
which is completely empty.  Let's just drop this function pointer and
simplify the code a bit.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:32:40 -04:00
Dominique Martinet c86c90c656 NFSv4: handle nfs4_get_referral failure
nfs4_proc_lookup_common is supposed to return a posix error, we have to
handle any error returned that isn't errno

Reported-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Frank S. Filz <ffilzlnx@mindspring.com>
Signed-off-by: Dominique Martinet <dominique.martinet@cea.fr>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:28:02 -04:00
Jeff Layton 3c87ef6efb sunrpc: keep a count of swapfiles associated with the rpc_clnt
Jerome reported seeing a warning pop when working with a swapfile on
NFS. The nfs_swap_activate can end up calling sk_set_memalloc while
holding the rcu_read_lock and that function can sleep.

To fix that, we need to take a reference to the xprt while holding the
rcu_read_lock, set the socket up for swapping and then drop that
reference. But, xprt_put is not exported and having NFS deal with the
underlying xprt is a bit of layering violation anyway.

Fix this by adding a set of activate/deactivate functions that take a
rpc_clnt pointer instead of an rpc_xprt, and have nfs_swap_activate and
nfs_swap_deactivate call those.

Also, add a per-rpc_clnt atomic counter to keep track of the number of
active swapfiles associated with it. When the counter does a 0->1
transition, we enable swapping on the xprt, when we do a 1->0 transition
we disable swapping on it.

This also allows us to be a bit more selective with the RPC_TASK_SWAPPER
flag. If non-swapper and swapper clnts are sharing a xprt, then we only
need to flag the tasks from the swapper clnt with that flag.

Acked-by: Mel Gorman <mgorman@suse.de>
Reported-by: Jerome Marchand <jmarchan@redhat.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-10 18:26:14 -04:00
Zhao Lei 9a4e7276d3 btrfs: wait for delayed iputs on no space
btrfs will report no_space when we run following write and delete
file loop:
 # FILE_SIZE_M=[ 75% of fs space ]
 # DEV=[ some dev ]
 # MNT=[ some dir ]
 #
 # mkfs.btrfs -f "$DEV"
 # mount -o nodatacow "$DEV" "$MNT"
 # for ((i = 0; i < 100; i++)); do dd if=/dev/zero of="$MNT"/file0 bs=1M count="$FILE_SIZE_M"; rm -f "$MNT"/file0; done
 #

Reason:
 iput() and evict() is run after write pages to block device, if
 write pages work is not finished before next write, the "rm"ed space
 is not freed, and caused above bug.

Fix:
 We can add "-o flushoncommit" mount option to avoid above bug, but
 it have performance problem. Actually, we can to wait for on-the-fly
 writes only when no-space happened, it is which this patch do.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:34 -07:00
Qu Wenruo d672633545 btrfs: qgroup: Make snapshot accounting work with new extent-oriented
qgroup.

Make snapshot accounting work with new extent-oriented mechanism by
skipping given root in new/old_roots in create_pending_snapshot().

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:29 -07:00
Qu Wenruo 9086db86e0 btrfs: qgroup: Add the ability to skip given qgroup for old/new_roots.
This is used by later qgroup fix patches for snapshot.

As current snapshot accounting is done by btrfs_qgroup_inherit(), but
new extent oriented quota mechanism will account extent from
btrfs_copy_root() and other snapshot things, causing wrong result.

So add this ability to handle snapshot accounting.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:23 -07:00
Qu Wenruo d4b8040459 btrfs: ulist: Add ulist_del() function.
This function will delete unode with given (val,aux) pair.
And with this patch, seqnum for debug usage doesn't have any meaning
now, so remove them.

This is used by later patches to skip snapshot root.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:17 -07:00
Qu Wenruo e69bcee376 btrfs: qgroup: Cleanup the old ref_node-oriented mechanism.
Goodbye, the old mechanisim.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:11 -07:00
Qu Wenruo 442244c963 btrfs: qgroup: Switch self test to extent-oriented qgroup mechanism.
Since the self test transaction don't have delayed_ref_roots, so use
find_all_roots() and export btrfs_qgroup_account_extent() to simulate it

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:26:05 -07:00
Qu Wenruo 0ed4792af0 btrfs: qgroup: Switch to new extent-oriented qgroup mechanism.
Switch from old ref_node based qgroup to extent based qgroup mechanism
for normal operations.

The new mechanism should hugely reduce the overhead of btrfs quota
system, and further more, the codes and logic should be more clean and
easier to maintain.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:59 -07:00
Qu Wenruo 9d220c95f5 btrfs: qgroup: Switch rescan to new mechanism.
Switch rescan to use the new new extent oriented mechanism.

As rescan is also based on extent, new mechanism is just a perfect match
for rescan.

With re-designed internal functions, rescan is quite easy, just call
btrfs_find_all_roots() and then btrfs_qgroup_account_one_extent().

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:54 -07:00
Qu Wenruo 550d7a2ed5 btrfs: qgroup: Add new qgroup calculation function
btrfs_qgroup_account_extents().

The new btrfs_qgroup_account_extents() function should be called in
btrfs_commit_transaction() and it will update all the qgroup according
to delayed_ref_root->dirty_extent_root.

The new function can handle both normal operation during
commit_transaction() or in rescan in a unified method with clearer
logic.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:49 -07:00
Qu Wenruo 21633fc603 btrfs: backref: Add special time_seq == (u64)-1 case for
btrfs_find_all_roots().

Allow btrfs_find_all_roots() to skip all delayed_ref_head lock and tree
lock to do tree search.

This is important for later qgroup implement which will call
find_all_roots() after fs trees are committed.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:45 -07:00
Qu Wenruo 3b7d00f99c btrfs: qgroup: Add new function to record old_roots.
Add function btrfs_qgroup_prepare_account_extents() to get old_roots
which are needed for qgroup.

We do it in commit_transaction() and before switch_roots(), and only
search commit_root, so it gives a quite accurate view for previous
transaction.

With old_roots from previous transaction, we can use it to do accurate
account with current transaction.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:39 -07:00
Qu Wenruo 3368d001ba btrfs: qgroup: Record possible quota-related extent for qgroup.
Add hook in add_delayed_ref_head() to record quota-related extent record
into delayed_ref_root->dirty_extent_record rb-tree for later qgroup
accounting.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:32 -07:00
Qu Wenruo 823ae5b8e3 btrfs: qgroup: Add function qgroup_update_counters().
Add function qgroup_update_counters(), which will update related
qgroups' rfer/excl according to old/new_roots.

This is one of the two core functions for the new qgroup implement.

This is based on btrfs_adjust_coutners() but with clearer logic and
comment.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:28 -07:00
Qu Wenruo d810ef2be5 btrfs: qgroup: Add function qgroup_update_refcnt().
This function is used to update refcnt for qgroups.
And is one of the two core functions used in the new qgroup implement.

This is based on the old update_old/new_refcnt, but provides a unified
logic and behavior.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:24 -07:00
Qu Wenruo c682f9b3c2 btrfs: extent-tree: Use ref_node to replace unneeded parameters in __inc_extent_ref() and __free_extent()
__btrfs_inc_extent_ref() and __btrfs_free_extent() have already had too
many parameters, but three of them can be extracted from
btrfs_delayed_ref_node struct.

So use btrfs_delayed_ref_node struct as a single parameter to replace
the bytenr/num_byte/no_quota parameters.

The real objective of this patch is to allow btrfs_qgroup_record_ref()
get the delayed_ref_node in incoming qgroup patches.

Other functions calling btrfs_qgroup_record_ref() are not affected since
the rest will only add/sub exclusive extents, where node is not used.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:18 -07:00
Qu Wenruo 9c542136fd btrfs: qgroup: Cleanup open-coded old/new_refcnt update and read.
Use inline functions to do such things, to improve readability.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Acked-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:13 -07:00
Qu Wenruo c43d160fcd btrfs: delayed-ref: Cleanup the unneeded functions.
Cleanup the rb_tree merge/insert/update functions, since now we use list
instead of rb_tree now.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:09 -07:00
Qu Wenruo c6fc245499 btrfs: delayed-ref: Use list to replace the ref_root in ref_head.
This patch replace the rbtree used in ref_head to list.
This has the following advantage:
1) Easier merge logic.
With the new list implement, we only need to care merging the tail
ref_node with the new ref_node.
And this can be done quite easy at insert time, no need to do a
indicated merge at run_delayed_refs().

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:25:03 -07:00
Qu Wenruo 00db646d3f btrfs: backref: Don't merge refs which are not for same block.
Old __merge_refs() in backref.c will even merge refs whose root_id are
different, which makes qgroup gives wrong result.

Fix it by checking ref_for_same_block() before any mode specific works.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 09:24:59 -07:00
Zhao Lei 20b2e3029e btrfs: Fix lockdep warning of wr_ctx->wr_lock in scrub_free_wr_ctx()
lockdep report following warning in test:
 [25176.843958] =================================
 [25176.844519] [ INFO: inconsistent lock state ]
 [25176.845047] 4.1.0-rc3 #22 Tainted: G        W
 [25176.845591] ---------------------------------
 [25176.846153] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
 [25176.846713] fsstress/26661 [HC0[0]:SC1[1]:HE1:SE0] takes:
 [25176.847246]  (&wr_ctx->wr_lock){+.?...}, at: [<ffffffffa04cdc6d>] scrub_free_ctx+0x2d/0xf0 [btrfs]
 [25176.847838] {SOFTIRQ-ON-W} state was registered at:
 [25176.848396]   [<ffffffff810bf460>] __lock_acquire+0x6a0/0xe10
 [25176.848955]   [<ffffffff810bfd1e>] lock_acquire+0xce/0x2c0
 [25176.849491]   [<ffffffff816489af>] mutex_lock_nested+0x7f/0x410
 [25176.850029]   [<ffffffffa04d04ff>] scrub_stripe+0x4df/0x1080 [btrfs]
 [25176.850575]   [<ffffffffa04d11b1>] scrub_chunk.isra.19+0x111/0x130 [btrfs]
 [25176.851110]   [<ffffffffa04d144c>] scrub_enumerate_chunks+0x27c/0x510 [btrfs]
 [25176.851660]   [<ffffffffa04d3b87>] btrfs_scrub_dev+0x1c7/0x6c0 [btrfs]
 [25176.852189]   [<ffffffffa04e918e>] btrfs_dev_replace_start+0x36e/0x450 [btrfs]
 [25176.852771]   [<ffffffffa04a98e0>] btrfs_ioctl+0x1e10/0x2d20 [btrfs]
 [25176.853315]   [<ffffffff8121c5b8>] do_vfs_ioctl+0x318/0x570
 [25176.853868]   [<ffffffff8121c851>] SyS_ioctl+0x41/0x80
 [25176.854406]   [<ffffffff8164da17>] system_call_fastpath+0x12/0x6f
 [25176.854935] irq event stamp: 51506
 [25176.855511] hardirqs last  enabled at (51506): [<ffffffff810d4ce5>] vprintk_emit+0x225/0x5e0
 [25176.856059] hardirqs last disabled at (51505): [<ffffffff810d4b77>] vprintk_emit+0xb7/0x5e0
 [25176.856642] softirqs last  enabled at (50886): [<ffffffff81067a23>] __do_softirq+0x363/0x640
 [25176.857184] softirqs last disabled at (50949): [<ffffffff8106804d>] irq_exit+0x10d/0x120
 [25176.857746]
 other info that might help us debug this:
 [25176.858845]  Possible unsafe locking scenario:
 [25176.859981]        CPU0
 [25176.860537]        ----
 [25176.861059]   lock(&wr_ctx->wr_lock);
 [25176.861705]   <Interrupt>
 [25176.862272]     lock(&wr_ctx->wr_lock);
 [25176.862881]
  *** DEADLOCK ***

Reason:
 Above warning is caused by:
 Interrupt
 -> bio_endio()
 -> ...
 -> scrub_put_ctx()
 -> scrub_free_ctx() *1
 -> ...
 -> mutex_lock(&wr_ctx->wr_lock);

 scrub_put_ctx() is allowed to be called in end_bio interrupt, but
 in code design, it will never call scrub_free_ctx(sctx) in interrupe
 context(above *1), because btrfs_scrub_dev() get one additional
 reference of sctx->refs, which makes scrub_free_ctx() only called
 withine btrfs_scrub_dev().

 Now the code runs out of our wish, because free sequence in
 scrub_pending_bio_dec() have a gap.

 Current code:
 -----------------------------------+-----------------------------------
 scrub_pending_bio_dec()            |  btrfs_scrub_dev
 -----------------------------------+-----------------------------------
 atomic_dec(&sctx->bios_in_flight); |
 wake_up(&sctx->list_wait);         |
                                    | scrub_put_ctx()
                                    | -> atomic_dec_and_test(&sctx->refs)
 scrub_put_ctx(sctx);               |
 -> atomic_dec_and_test(&sctx->refs)|
 -> scrub_free_ctx()                |
 -----------------------------------+-----------------------------------

 We expected:
 -----------------------------------+-----------------------------------
 scrub_pending_bio_dec()            |  btrfs_scrub_dev
 -----------------------------------+-----------------------------------
 atomic_dec(&sctx->bios_in_flight); |
 wake_up(&sctx->list_wait);         |
 scrub_put_ctx(sctx);               |
 -> atomic_dec_and_test(&sctx->refs)|
                                    | scrub_put_ctx()
                                    | -> atomic_dec_and_test(&sctx->refs)
                                    | -> scrub_free_ctx()
 -----------------------------------+-----------------------------------

Fix:
 Move scrub_pending_bio_dec() to a workqueue, to avoid this function run
 in interrupt context.
 Tested by check tracelog in debug.

Changelog v1->v2:
 Use workqueue instead of adjust function call sequence in v1,
 because v1 will introduce a bug pointed out by:
 Filipe David Manana <fdmanana@gmail.com>

Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:04:52 -07:00
Mark Fasheh e1d227a42e btrfs: Handle unaligned length in extent_same
The extent-same code rejects requests with an unaligned length. This
poses a problem when we want to dedupe the tail extent of files as we
skip cloning the portion between i_size and the extent boundary.

If we don't clone the entire extent, it won't be deleted. So the
combination of these behaviors winds up giving us worst-case dedupe on
many files.

We can fix this by allowing a length that extents to i_size and
internally aligining those to the end of the block. This is what
btrfs_ioctl_clone() so we can just copy that check over.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:50 -07:00
chandan 070034bdf9 Btrfs: btrfs_defrag_file: Fix calculation of max_to_defrag.
max_to_defrag represents the number of pages to defrag rather than the last
page of the file range to be defragged.

Consider a file having 10 4k blocks (i.e. blocks in the range [0 - 9]). If the
defrag ioctl was invoked for the block range [3 - 6], then max_to_defrag
should actually have the value 4. Instead in the current code we end up
setting it to 6.

Now, this does not (yet) cause an issue since the first part of the while loop
condition in btrfs_defrag_file() (i.e. "i <= last_index") causes the control
to flow out of the while loop before any buggy behavior is actually caused. So
the patch just makes sure that max_to_defrag ends up having the right value
rather than fixing a bug. I did run the xfstests suite to make sure that the
code does not regress.

Changelog: v1->v2:
Provide a much descriptive commit message.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:48 -07:00
chandan e4826a5b24 Btrfs: btrfs_defrag_file: Fix ra_index computation.
Read-ahead is done for the pages in the range [ra_index, ra_index + cluster -
1]. So the next read-ahead should be starting from the page at index 'ra_index
+ cluster' (unless we deemed that the extent at 'ra_index + cluster' as
non-defraggable) rather than from the page at index 'ra_index +
max_cluster'. This patch fixes this. I did run the xfstests suite to make sure
that the code does not regress.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:47 -07:00
Filipe Manana 4617ea3a52 Btrfs: fix necessary chunk tree space calculation when allocating a chunk
When allocating a new chunk or removing one we need to update num_devs
device items and insert or remove a chunk item in the chunk tree, so
in the worst case the space needed in the chunk space_info is:

  btrfs_calc_trunc_metadata_size(chunk_root, num_devs) +
     btrfs_calc_trans_metadata_size(chunk_root, 1)

That is, in the worst case we need to cow num_devs paths and cow 1 other
path that can result in splitting every node and leaf, and each path
consisting of BTRFS_MAX_LEVEL - 1 nodes and 1 leaf. We were requiring
some additional chunk_root->nodesize * BTRFS_MAX_LEVEL * num_devs bytes,
which were unnecessary since updating the existing device items does
not result in splitting the nodes and leaf since after updating them
they remain with the same size.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:46 -07:00
Filipe Manana 7558c8bc17 Btrfs: don't attach unnecessary extents to transaction on fsync
We don't need to attach ordered extents that have completed to the current
transaction. Doing so only makes us hold memory for longer than necessary
and delaying the iput of the inode until the transaction is committed (for
each created ordered extent we do an igrab and then schedule an asynchronous
iput when the ordered extent's reference count drops to 0), preventing the
inode from being evictable until the transaction commits.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:44 -07:00
Filipe Manana b659ef0277 Btrfs: avoid syncing log in the fast fsync path when not necessary
Commit 3a8b36f378 ("Btrfs: fix data loss in the fast fsync path") added
a performance regression for that causes an unnecessary sync of the log
trees (fs/subvol and root log trees) when 2 consecutive fsyncs are done
against a file, without no writes or any metadata updates to the inode in
between them and if a transaction is committed before the second fsync is
called.

Huang Ying reported this to lkml (https://lkml.org/lkml/2015/3/18/99)
after a test sysbench test that measured a -62% decrease of file io
requests per second for that tests' workload.

The test is:

  echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
  echo performance > /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor
  echo performance > /sys/devices/system/cpu/cpu2/cpufreq/scaling_governor
  echo performance > /sys/devices/system/cpu/cpu3/cpufreq/scaling_governor
  mkfs -t btrfs /dev/sda2
  mount -t btrfs /dev/sda2 /fs/sda2
  cd /fs/sda2
  for ((i = 0; i < 1024; i++)); do fallocate -l 67108864 testfile.$i; done
  sysbench --test=fileio --max-requests=0 --num-threads=4 --max-time=600 \
    --file-test-mode=rndwr --file-total-size=68719476736 --file-io-mode=sync \
    --file-num=1024 run

A test on kvm guest, running a debug kernel gave me the following results:

Without 3a8b36f378060d:             16.01 reqs/sec
With 3a8b36f378060d:                 3.39 reqs/sec
With 3a8b36f378 and this patch: 16.04 reqs/sec

Reported-by: Huang Ying <ying.huang@intel.com>
Tested-by: Huang, Ying <ying.huang@intel.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:43 -07:00
Chris Mason 1ab818b137 Merge branch 'send_fixes_4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.2 2015-06-10 07:02:41 -07:00
Jaegeuk Kim de6a8ec982 f2fs: drop the volatile_write flag only
When aborting volatile_writes, let's drop its flag and give up any further
volatile_writes.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-09 13:56:47 -07:00
Abhi Das 86066914ed gfs2: Don't support fallocate on jdata files
We cannot provide an efficient implementation due to the headers
on the data blocks, so there doesn't seem much point in having it.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-06-09 09:16:46 -05:00
Namjae Jeon 331573febb ext4: Add support FALLOC_FL_INSERT_RANGE for fallocate
This patch implements fallocate's FALLOC_FL_INSERT_RANGE for Ext4.

1) Make sure that both offset and len are block size aligned.
2) Update the i_size of inode by len bytes.
3) Compute the file's logical block number against offset. If the computed
   block number is not the starting block of the extent, split the extent
   such that the block number is the starting block of the extent.
4) Shift all the extents which are lying between [offset, last allocated extent]
   towards right by len bytes. This step will make a hole of len bytes
   at offset.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Ashish Sangwan <a.sangwan@samsung.com>
2015-06-09 01:55:03 -04:00
David S. Miller 941742f497 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-08 20:06:56 -07:00
Chao Yu c5bda1c8b1 f2fs: skip committing valid superblock
In recovery procedure for superblock, we try to write data of valid
superblock into invalid one for recovery, work should be finished here,
but then still we will write the valid one with its original data.
This operation is not needed. Let's skip doing this unnecessary work.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-08 11:20:51 -07:00
Chao Yu 09d54cdd20 f2fs: setting discard option in parse_options()
For the first mount of f2fs image with realtime discard option, we will
disable discard option if device is not supported, but for remount
operation, our discard option can still be set, this should be avoided.

This patch moves configuring of discard option to parse_options() to fix
this issue.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-08 11:09:19 -07:00
Greg Kroah-Hartman 987aec39a7 Merge 4.1-rc7 into driver-core-next
We want the fixes in this branch as well for testing and merge
resolution.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-08 10:19:40 -07:00
Jan Kara de92c8caf1 jbd2: speedup jbd2_journal_get_[write|undo]_access()
jbd2_journal_get_write_access() and jbd2_journal_get_create_access() are
frequently called for buffers that are already part of the running
transaction - most frequently it is the case for bitmaps, inode table
blocks, and superblock. Since in such cases we have nothing to do, it is
unfortunate we still grab reference to journal head, lock the bh, lock
bh_state only to find out there's nothing to do.

Improving this is a bit subtle though since until we find out journal
head is attached to the running transaction, it can disappear from under
us because checkpointing / commit decided it's no longer needed. We deal
with this by protecting journal_head slab with RCU. We still have to be
careful about journal head being freed & reallocated within slab and
about exposing journal head in consistent state (in particular
b_modified and b_frozen_data must be in correct state before we allow
user to touch the buffer).

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 12:46:37 -04:00
Jan Kara 8b00f400ee jbd2: more simplifications in do_get_write_access()
Check for the simple case of unjournaled buffer first, handle it and
bail out. This allows us to remove one if and unindent the difficult case
by one tab. The result is easier to read.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 12:44:21 -04:00
Jan Kara d012aa5965 jbd2: simplify error path on allocation failure in do_get_write_access()
We were acquiring bh_state_lock when allocation of buffer failed in
do_get_write_access() only to be able to jump to a label that releases
the lock and does all other checks that don't make sense for this error
path. Just jump into the right label instead.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 12:40:39 -04:00
Jan Kara ee57aba159 jbd2: simplify code flow in do_get_write_access()
needs_copy is set only in one place in do_get_write_access(), just move
the frozen buffer copying into that place and factor it out to a
separate function to make do_get_write_access() slightly more readable.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 12:39:07 -04:00
Fabian Frederick b4ab9e2982 ext4 crypto: fix sparse warnings in fs/ext4/ioctl.c
[ Added another sparse fix for EXT4_IOC_GET_ENCRYPTION_POLICY while
  we're at it. --tytso ]

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 12:23:21 -04:00
Abhi Das 1bdf45352e gfs2: s64 cast for negative quota value
One-line fix to cast quota value to s64 before comparison.
By default the quantity is treated as u64.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-06-08 11:20:50 -05:00
David Moore 8bc3b1e6e8 ext4: BUG_ON assertion repeated for inode1, not done for inode2
During a source code review of fs/ext4/extents.c I noted identical
consecutive lines. An assertion is repeated for inode1 and never done
for inode2. This is not in keeping with the rest of the code in the
ext4_swap_extents function and appears to be a bug.

Assert that the inode2 mutex is not locked.

Signed-off-by: David Moore <dmoorefo@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
2015-06-08 11:59:12 -04:00
Theodore Ts'o ad0a0ce894 ext4 crypto: fix ext4_get_crypto_ctx()'s calling convention in ext4_decrypt_one
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 11:54:56 -04:00
Lukas Czerner 42ac1848ea ext4: return error code from ext4_mb_good_group()
Currently ext4_mb_good_group() only returns 0 or 1 depending on whether
the allocation group is suitable for use or not. However we might get
various errors and fail while initializing new group including -EIO
which would never get propagated up the call chain. This might lead to
an endless loop at writeback when we're trying to find a good group to
allocate from and we fail to initialize new group (read error for
example).

Fix this by returning proper error code from ext4_mb_good_group() and
using it in ext4_mb_regular_allocator(). In ext4_mb_regular_allocator()
we will always return only the first occurred error from
ext4_mb_good_group() and we only propagate it back  to the caller if we
do not get any other errors and we fail to allocate any blocks.

Note that with other modes than errors=continue, we will fail
immediately in ext4_mb_good_group() in case of error, however with
errors=continue we should try to continue using the file system, that's
why we're not going to fail immediately when we see an error from
ext4_mb_good_group(), but rather when we fail to find a suitable block
group to allocate from due to an problem in group initialization.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
2015-06-08 11:40:40 -04:00
Lukas Czerner bbdc322f2c ext4: try to initialize all groups we can in case of failure on ppc64
Currently on the machines with page size > block size when initializing
block group buddy cache we initialize it for all the block group bitmaps
in the page. However in the case of read error, checksum error, or if
a single bitmap is in any way corrupted we would fail to initialize all
of the bitmaps. This is problematic because we will not have access to
the other allocation groups even though those might be perfectly fine
and usable.

Fix this by reading all the bitmaps instead of error out on the first
problem and simply skip the bitmaps which were either not read properly,
or are not valid.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 11:38:37 -04:00
Lukas Czerner 41e5b7ed3e ext4: verify block bitmap even after fresh initialization
If we want to rely on the buffer_verified() flag of the block bitmap
buffer, we have to set it consistently. However currently if we're
initializing uninitialized block bitmap in
ext4_read_block_bitmap_nowait() we're not going to set buffer verified
at all.

We can do this by simply setting the flag on the buffer, but I think
it's actually better to run ext4_validate_block_bitmap() to make sure
that what we did in the ext4_init_block_bitmap() is right.

So run ext4_validate_block_bitmap() even after the block bitmap
initialization. Also bail out early from ext4_validate_block_bitmap() if
we see corrupt bitmap, since we already know it's corrupt and we do not
need to verify that.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08 11:18:52 -04:00
Tejun Heo 412a19b64a v9fs: fix error handling in v9fs_session_init()
On failure, v9fs_session_init() returns with the v9fs_session_info
struct partially initialized and expects the caller to invoke
v9fs_session_close() to clean it up; however, it doesn't track whether
the bdi is initialized or not and curiously invokes bdi_destroy() in
both vfs_session_init() failure path too.

A. If v9fs_session_init() fails before the bdi is initialized, the
   follow-up v9fs_session_close() will invoke bdi_destroy() on an
   uninitialized bdi.

B. If v9fs_session_init() fails after the bdi is initialized,
   bdi_destroy() will be called twice on the same bdi - once in the
   failure path of v9fs_session_init() and then by
   v9fs_session_close().

A is broken no matter what.  B used to be okay because bdi_destroy()
allowed being invoked multiple times on the same bdi, which BTW was
broken in its own way - if bdi_destroy() was invoked on an initialiezd
but !registered bdi, it'd fail to free percpu counters.  Since
f0054bb1e1 ("writeback: move backing_dev_info->wb_lock and
->worklist into bdi_writeback"), this no longer work - bdi_destroy()
on an initialized but not registered bdi works correctly but multiple
invocations of bdi_destroy() is no longer allowed.

The obvious culprit here is v9fs_session_init()'s odd and broken error
behavior.  It should simply clean up after itself on failures.  This
patch makes the following updates to v9fs_session_init().

* @rc -> @retval error return propagation removed.  It didn't serve
  any purpose.  Just use @rc.

* Move addition to v9fs_sessionlist to the end of the function so that
  incomplete sessions are not put on the list or iterated and error
  path doesn't have to worry about it.

* Update error handling so that it cleans up after itself.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-08 09:05:06 -06:00
Michal Hocko 6ccaf3e2f3 jbd2: revert must-not-fail allocation loops back to GFP_NOFAIL
This basically reverts 47def82672 (jbd2: Remove __GFP_NOFAIL from jbd2
layer). The deprecation of __GFP_NOFAIL was a bad choice because it led
to open coding the endless loop around the allocator rather than
removing the dependency on the non failing allocation. So the
deprecation was a clear failure and the reality tells us that
__GFP_NOFAIL is not even close to go away.

It is still true that __GFP_NOFAIL allocations are generally discouraged
and new uses should be evaluated and an alternative (pre-allocations or
reservations) should be considered but it doesn't make any sense to lie
the allocator about the requirements. Allocator can take steps to help
making a progress if it knows the requirements.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Acked-by: David Rientjes <rientjes@google.com>
2015-06-08 10:53:10 -04:00
Kinglong Mee 276f03e3ba nfsd: Update callback sequnce id only CB_SEQUENCE success
When testing pnfs layout, nfsd got error NFS4ERR_SEQ_MISORDERED.
It is caused by nfs return NFS4ERR_DELAY before validate_seqid(),
don't update the sequnce id, but nfsd updates the sequnce id !!!

According to RFC5661 20.9.3,
" If CB_SEQUENCE returns an error, then the state of the slot
(sequence ID, cached reply) MUST NOT change. "

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-04 16:51:30 -04:00
Kinglong Mee 4399396eec nfsd: Reset cb_status in nfsd4_cb_prepare() at retrying
nfsd enters a infinite loop and prints message every 10 seconds:

May 31 18:33:52 test-server kernel: Error sending entire callback!
May 31 18:34:01 test-server kernel: Error sending entire callback!

This is caused by a cb_layoutreturn getting error -10008
(NFS4ERR_DELAY), the client crashing, and then nfsd entering the
infinite loop:

  bc_sendto --> call_timeout --> nfsd4_cb_done --> nfsd4_cb_layout_done
  with error -10008 --> rpc_delay(task, HZ/100) --> bc_sendto ...

Reproduced using xfstests 074 with nfs client's kdump on,
CONFIG_DEFAULT_HUNG_TASK_TIMEOUT set, and client's blkmapd down:

1. nfs client's write operation will get the layout of file,
   and then send getdeviceinfo,
2. but layout segment is not recorded by client because blkmapd is down,
3. client writes data by sending WRITE to server,
4. nfs server recalls the layout of the file before WRITE,
5. network error causes the client reset the session and return NFS4ERR_DELAY,
6. so client's WRITE operation is waiting the reply.
   If the task hangs 120s, the client will crash.
7. so that, the next bc_sendto will fail with TIMEOUT,
   and cb_status is NFS4ERR_DELAY.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2015-06-04 16:43:39 -04:00
Trond Myklebust 8eee52af27 NFSv4: nfs4_handle_delegation_recall_error should ignore EAGAIN
EAGAIN is a valid return code from nfs4_open_recover(), and should
be handled by nfs4_handle_delegation_recall_error by simply passing
it through.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-06-04 13:51:13 -04:00
Eric W. Biederman 8c6cf9cc82 mnt: Modify fs_fully_visible to deal with locked ro nodev and atime
Ignore an existing mount if the locked readonly, nodev or atime
attributes are less permissive than the desired attributes
of the new mount.

On success ensure the new mount locks all of the same readonly, nodev and
atime attributes as the old mount.

The nosuid and noexec attributes are not checked here as this change
is destined for stable and enforcing those attributes causes a
regression in lxc and libvirt-lxc where those applications will not
start and there are no known executables on sysfs or proc and no known
way to create exectuables without code modifications

Cc: stable@vger.kernel.org
Fixes: e51db73532 ("userns: Better restrictions on when proc and sysfs can be mounted")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-06-04 10:29:25 -05:00
Dave Chinner 4ea7976616 Merge branch 'xfs-commit-cleanup' into for-next
Conflicts:
	fs/xfs/xfs_attr_inactive.c
2015-06-04 13:55:48 +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
Christoph Hellwig 70393313dd xfs: saner xfs_trans_commit interface
The flags argument to xfs_trans_commit is not useful for most callers, as
a commit of a transaction without a permanent log reservation must pass
0 here, and all callers for a transaction with a permanent log reservation
except for xfs_trans_roll must pass XFS_TRANS_RELEASE_LOG_RES.  So remove
the flags argument from the public xfs_trans_commit interfaces, and
introduce low-level __xfs_trans_commit variant just for xfs_trans_roll
that regrants a log reservation instead of releasing it.

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 13:48:08 +10:00
Christoph Hellwig 4906e21545 xfs: remove the flags argument to xfs_trans_cancel
xfs_trans_cancel takes two flags arguments: XFS_TRANS_RELEASE_LOG_RES and
XFS_TRANS_ABORT.  Both of them are a direct product of the transaction
state, and can be deducted:

 - any dirty transaction needs XFS_TRANS_ABORT to be properly canceled,
   and XFS_TRANS_ABORT is a noop for a transaction that is not dirty.
 - any transaction with a permanent log reservation needs
   XFS_TRANS_RELEASE_LOG_RES to be properly canceled, and passing
   XFS_TRANS_RELEASE_LOG_RES for a transaction without a permanent
   log reservation is invalid.

So just remove the flags argument and do the right thing.

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 13:47:56 +10:00
Christoph Hellwig eacb24e734 xfs: pass a boolean flag to xfs_trans_free_items
The flags value always was 0 or XFS_TRANS_ABORT.  Switch to a bool
parameter to allow further cleanups.

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 13:47:43 +10:00
Christoph Hellwig 2e6db6c4c1 xfs: switch remaining xfs_trans_dup users to xfs_trans_roll
We have three remaining callers of xfs_trans_dup:

 - xfs_itruncate_extents which open codes xfs_trans_roll
 - xfs_bmap_finish doesn't have an xfs_inode argument and thus leaves
   attaching them to it's callers, but otherwise is identical to
   xfs_trans_roll
 - xfs_dir_ialloc looks at the log reservations in the old xfs_trans
   structure instead of the log reservation parameters, but otherwise
   is identical to xfs_trans_roll.

By allowing a NULL xfs_inode argument to xfs_trans_roll we can switch
these three remaining users over to xfs_trans_roll and mark xfs_trans_dup
static.

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 13:47:29 +10:00
Dave Chinner 4497f28750 Merge branch 'xfs-misc-fixes-for-4.2-2' into for-next 2015-06-04 13:31:13 +10:00
Brian Foster 46fc58dacf xfs: check min blks for random debug mode sparse allocations
The inode allocator enables random sparse inode chunk allocations in
DEBUG mode to facilitate testing. Sparse inode allocations are not
always possible, however, depending on the fs geometry. For example,
there is no possibility for a sparse inode allocation on filesystems
where the block size is large enough to fit one or more inode chunks
within a single block.

Fix up the DEBUG mode sparse inode allocation logic to trigger random
sparse allocations only when the geometry of the fs allows it.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 13:03:34 +10:00
Brian Foster 3cdaa1898f xfs: fix sparse inodes 32-bit compile failure
The kbuild test robot reports the following compilation failure with a
32-bit kernel configuration:

	fs/built-in.o: In function `xfs_ifree_cluster':
	>> xfs_inode.c:(.text+0x17ac84): undefined reference to `__umoddi3'

This is due to the use of the modulus operator on a 64-bit variable in
the ASSERT() added as part of the following commit:

	xfs: skip unallocated regions of inode chunks in xfs_ifree_cluster()

This ASSERT() simply checks that the offset of the inode in a sparse
cluster is appropriately aligned. Since the maximum inode record offset
is 63 (for a 64 inode record) and the calculated offset here should be
something less than that, just use a 32-bit variable to store the offset
and call the do_mod() helper.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 13:03:34 +10:00
Dave Chinner 66e8ac7bfa Merge branch 'xfs-dax-support' into for-next 2015-06-04 13:01:49 +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
Dave Chinner 6e1ba0bcb8 xfs: add DAX IO path support
DAX does not do buffered IO (can't buffer direct access!) and hence
all read/write IO is vectored through the direct IO path.  Hence we
need to add the DAX IO path callouts to the direct IO
infrastructure.

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 09:19:15 +10:00
Dave Chinner 9969441f9f xfs: add DAX truncate support
When we truncate a DAX file, we need to call through the DAX page
truncation path rather than through block_truncate_page() so that
mappings and block zeroing are all handled correctly. Otherwise,
truncate does not need to change.

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 09:19:10 +10:00
Dave Chinner 4f69f578a8 xfs: add DAX block zeroing support
Add initial support for DAX block zeroing operations to XFS. DAX
cannot use buffered IO through the page cache for zeroing, nor do we
need to issue IO for uncached block zeroing. In both cases, we can
simply call out to the dax block zeroing function.

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 09:19:08 +10:00
Dave Chinner 6b698edeee xfs: add DAX file operations support
Add the initial support for DAX file operations to XFS. This
includes the necessary block allocation and mmap page fault hooks
for DAX to function.

Note that there are changes to the splice interfaces to ensure that
for DAX splice avoids direct page cache manipulations and instead
takes the DAX IO paths for read/write operations.

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 09:18:53 +10:00
Dave Chinner ce5c5d554d dax: expose __dax_fault for filesystems with locking constraints
Some filesystems cannot call dax_fault() directly because they have
different locking and/or allocation constraints in the page fault IO
path. To handle this, we need to follow the same model as the
generic block_page_mkwrite code, where the internals are exposed via
__block_page_mkwrite() so that filesystems can wrap the correct
locking and operations around the outside. 

This is loosely based on a patch originally from Matthew Willcox.
Unlike the original patch, it does not change ext4 code, error
returns or unwritten extent conversion handling.  It also adds a
__dax_mkwrite() wrapper for .page_mkwrite implementations to do the
right thing, too.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 09:18:18 +10:00
Dave Chinner e842f29039 dax: don't abuse get_block mapping for endio callbacks
dax_fault() currently relies on the get_block callback to attach an
io completion callback to the mapping buffer head so that it can
run unwritten extent conversion after zeroing allocated blocks.

Instead of this hack, pass the conversion callback directly into
dax_fault() similar to the get_block callback. When the filesystem
allocates unwritten extents, it will set the buffer_unwritten()
flag, and hence the dax_fault code can call the completion function
in the contexts where it is necessary without overloading the
mapping buffer head.

Note: The changes to ext4 to use this interface are suspect at best.
In fact, the way ext4 did this end_io assignment in the first place
looks suspect because it only set a completion callback when there
wasn't already some other write() call taking place on the same
inode. The ext4 end_io code looks rather intricate and fragile with
all it's reference counting and passing to different contexts for
modification via inode private pointers that aren't protected by
locks...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 09:18:18 +10:00
Dave Chinner ec56b1f1fd xfs: mmap lock needs to be inside freeze protection
Lock ordering for the new mmap lock needs to be:

mmap_sem
  sb_start_pagefault
    i_mmap_lock
      page lock
        <fault processsing>

Right now xfs_vm_page_mkwrite gets this the wrong way around,
While technically it cannot deadlock due to the current freeze
ordering, it's still a landmine that might explode if we change
anything in future. Hence we need to nest the locks correctly.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>
2015-06-04 09:18:18 +10:00
Theodore Ts'o 3dbb5eb9a3 ext4 crypto: allocate bounce pages using GFP_NOWAIT
Previously we allocated bounce pages using a combination of
alloc_page() and mempool_alloc() with the __GFP_WAIT bit set.
Instead, use mempool_alloc() with GFP_NOWAIT.  The mempool_alloc()
function will try using alloc_pages() initially, and then only use the
mempool reserve of pages if alloc_pages() is unable to fulfill the
request.

This minimizes the the impact on the mm layer when we need to do a
large amount of writeback of encrypted files, as Jaeguk Kim had
reported that under a heavy fio workload on a system with restricted
amounts memory (which unfortunately, includes many mobile handsets),
he had observed the the OOM killer getting triggered several times.
Using GFP_NOWAIT

If the mempool_alloc() function fails, we will retry the page
writeback at a later time; the function of the mempool is to ensure
that we can writeback at least 32 pages at a time, so we can more
efficiently dispatch I/O under high memory pressure situations.  In
the future we should make this be a tunable so we can determine the
best tradeoff between permanently sequestering memory and the ability
to quickly launder pages so we can free up memory quickly when
necessary.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-03 09:32:39 -04:00
Filipe Manana 6ca0709756 Btrfs: fix hang during inode eviction due to concurrent readahead
Zygo Blaxell and other users have reported occasional hangs while an
inode is being evicted, leading to traces like the following:

[ 5281.972322] INFO: task rm:20488 blocked for more than 120 seconds.
[ 5281.973836]       Not tainted 4.0.0-rc5-btrfs-next-9+ #2
[ 5281.974818] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 5281.976364] rm              D ffff8800724cfc38     0 20488   7747 0x00000000
[ 5281.977506]  ffff8800724cfc38 ffff8800724cfc38 ffff880065da5c50 0000000000000001
[ 5281.978461]  ffff8800724cffd8 ffff8801540a5f50 0000000000000008 ffff8801540a5f78
[ 5281.979541]  ffff8801540a5f50 ffff8800724cfc58 ffffffff8143107e 0000000000000123
[ 5281.981396] Call Trace:
[ 5281.982066]  [<ffffffff8143107e>] schedule+0x74/0x83
[ 5281.983341]  [<ffffffffa03b33cf>] wait_on_state+0xac/0xcd [btrfs]
[ 5281.985127]  [<ffffffff81075cd6>] ? signal_pending_state+0x31/0x31
[ 5281.986715]  [<ffffffffa03b4b71>] wait_extent_bit.constprop.32+0x7c/0xde [btrfs]
[ 5281.988680]  [<ffffffffa03b540b>] lock_extent_bits+0x5d/0x88 [btrfs]
[ 5281.990200]  [<ffffffffa03a621d>] btrfs_evict_inode+0x24e/0x5be [btrfs]
[ 5281.991781]  [<ffffffff8116964d>] evict+0xa0/0x148
[ 5281.992735]  [<ffffffff8116a43d>] iput+0x18f/0x1e5
[ 5281.993796]  [<ffffffff81160d4a>] do_unlinkat+0x15b/0x1fa
[ 5281.994806]  [<ffffffff81435b54>] ? ret_from_sys_call+0x1d/0x58
[ 5281.996120]  [<ffffffff8107d314>] ? trace_hardirqs_on_caller+0x18f/0x1ab
[ 5281.997562]  [<ffffffff8123960b>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[ 5281.998815]  [<ffffffff81161a16>] SyS_unlinkat+0x29/0x2b
[ 5281.999920]  [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[ 5282.001299] 1 lock held by rm/20488:
[ 5282.002066]  #0:  (sb_writers#12){.+.+.+}, at: [<ffffffff8116dd81>] mnt_want_write+0x24/0x4b

This happens when we have readahead, which calls readpages(), happening
right before the inode eviction handler is invoked. So the reason is
essentially:

1) readpages() is called while a reference on the inode is held, so
   eviction can not be triggered before readpages() returns. It also
   locks one or more ranges in the inode's io_tree (which is done at
   extent_io.c:__do_contiguous_readpages());

2) readpages() submits several read bios, all with an end io callback
   that runs extent_io.c:end_bio_extent_readpage() and that is executed
   by other task when a bio finishes, corresponding to a work queue
   (fs_info->end_io_workers) worker kthread. This callback unlocks
   the ranges in the inode's io_tree that were previously locked in
   step 1;

3) readpages() returns, the reference on the inode is dropped;

4) One or more of the read bios previously submitted are still not
   complete (their end io callback was not yet invoked or has not
   yet finished execution);

5) Inode eviction is triggered (through an unlink call for example).
   The inode reference count was not incremented before submitting
   the read bios, therefore this is possible;

6) The eviction handler starts executing and enters the loop that
   iterates over all extent states in the inode's io_tree;

7) The loop picks one extent state record and uses its ->start and
   ->end fields, after releasing the inode's io_tree spinlock, to
   call lock_extent_bits() and clear_extent_bit(). The call to lock
   the range [state->start, state->end] blocks because the whole
   range or a part of it was locked by the previous call to
   readpages() and the corresponding end io callback, which unlocks
   the range was not yet executed;

8) The end io callback for the read bio is executed and unlocks the
   range [state->start, state->end] (or a superset of that range).
   And at clear_extent_bit() the extent_state record state is used
   as a second argument to split_state(), which sets state->start to
   a larger value;

9) The task executing the eviction handler is woken up by the task
   executing the bio's end io callback (through clear_state_bit) and
   the eviction handler locks the range
   [old value for state->start, state->end]. Shortly after, when
   calling clear_extent_bit(), it unlocks the range
   [new value for state->start, state->end], so it ends up unlocking
   only part of the range that it locked, leaving an extent state
   record in the io_tree that represents the unlocked subrange;

10) The eviction handler loop, in its next iteration, gets the
    extent_state record for the subrange that it did not unlock in the
    previous step and then tries to lock it, resulting in an hang.

So fix this by not using the ->start and ->end fields of an existing
extent_state record. This is a simple solution, and an alternative
could be to bump the inode's reference count before submitting each
read bio and having it dropped in the bio's end io callback. But that
would be a more invasive/complex change and would not protect against
other possible places that are not holding a reference on the inode
as well. Something to consider in the future.

Many thanks to Zygo Blaxell for reporting, in the mailing list, the
issue, a set of scripts to trigger it and testing this fix.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Tested-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:09 -07:00
Liu Bo 64c043de46 Btrfs: fix up read_tree_block to return proper error
The return value of read_tree_block() can confuse callers as it always
returns NULL for either -ENOMEM or -EIO, so it's likely that callers
parse it to a wrong error, for instance, in btrfs_read_tree_root().

This fixes the above issue.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:08 -07:00
Liu Bo 8635eda91e Btrfs: add missing free_extent_buffer
read_tree_block may take a reference on the 'eb', a following
free_extent_buffer is necessary.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:07 -07:00
Liu Bo 0c304304fe Btrfs: remove csum_bytes_left
After commit 8407f55326
("Btrfs: fix data corruption after fast fsync and writeback error"),
during wait_ordered_extents(), we wait for ordered extent setting
BTRFS_ORDERED_IO_DONE or BTRFS_ORDERED_IOERR, at which point we've
already got checksum information, so we don't need to check
(csum_bytes_left == 0) in the whole logging path.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:06 -07:00
Filipe Manana 39c2d7facc Btrfs: fix -ENOSPC on block group removal
Unlike when attempting to allocate a new block group, where we check
that we have enough space in the system space_info to update the device
items and insert a new chunk item in the chunk tree, we were not checking
if the system space_info had enough space for updating the device items
and deleting the chunk item in the chunk tree. This often lead to -ENOSPC
error when attempting to allocate blocks for the chunk tree (during btree
node/leaf COW operations) while updating the device items or deleting the
chunk item, which resulted in the current transaction being aborted and
turning the filesystem into read-only mode.

While running fstests generic/038, which stresses allocation of block
groups and removal of unused block groups, with a large scratch device
(750Gb) this happened often, despite more than enough unallocated space,
and resulted in the following trace:

[68663.586604] WARNING: CPU: 3 PID: 1521 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
[68663.600407] BTRFS: Transaction aborted (error -28)
(...)
[68663.730829] Call Trace:
[68663.732585]  [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[68663.734334]  [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[68663.739980]  [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[68663.757153]  [<ffffffffa036ca6d>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[68663.760925]  [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[68663.762854]  [<ffffffffa03b159d>] ? btrfs_update_device+0x15a/0x16c [btrfs]
[68663.764073]  [<ffffffffa036ca6d>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[68663.765130]  [<ffffffffa03b3638>] btrfs_remove_chunk+0x597/0x5ee [btrfs]
[68663.765998]  [<ffffffffa0384663>] ? btrfs_delete_unused_bgs+0x245/0x296 [btrfs]
[68663.767068]  [<ffffffffa0384676>] btrfs_delete_unused_bgs+0x258/0x296 [btrfs]
[68663.768227]  [<ffffffff8143527f>] ? _raw_spin_unlock_irq+0x2d/0x4c
[68663.769081]  [<ffffffffa038b109>] cleaner_kthread+0x13d/0x16c [btrfs]
[68663.799485]  [<ffffffffa038afcc>] ? btrfs_alloc_root+0x28/0x28 [btrfs]
[68663.809208]  [<ffffffff8105f367>] kthread+0xef/0xf7
[68663.828795]  [<ffffffff810e603f>] ? time_hardirqs_on+0x15/0x28
[68663.844942]  [<ffffffff8105f278>] ? __kthread_parkme+0xad/0xad
[68663.846486]  [<ffffffff81435a88>] ret_from_fork+0x58/0x90
[68663.847760]  [<ffffffff8105f278>] ? __kthread_parkme+0xad/0xad
[68663.849503] ---[ end trace 798477c6d6dbaad6 ]---
[68663.850525] BTRFS: error (device sdc) in btrfs_remove_chunk:2652: errno=-28 No space left

So fix this by verifying that enough space exists in system space_info,
and reserving the space in the chunk block reserve, before attempting to
delete the block group and allocate a new system chunk if we don't have
enough space to perform the necessary updates and delete in the chunk
tree. Like for the block group creation case, we don't error our if we
fail to allocate a new system chunk, since we might end up not needing
it (no node/leaf splits happen during the COW operations and/or we end
up not needing to COW any btree nodes or leafs because they were already
COWed in the current transaction and their writeback didn't start yet).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:05 -07:00
Filipe Manana 4fbcdf6694 Btrfs: fix -ENOSPC when finishing block group creation
While creating a block group, we often end up getting ENOSPC while updating
the chunk tree, which leads to a transaction abortion that produces a trace
like the following:

[30670.116368] WARNING: CPU: 4 PID: 20735 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x106 [btrfs]()
[30670.117777] BTRFS: Transaction aborted (error -28)
(...)
[30670.163567] Call Trace:
[30670.163906]  [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[30670.164522]  [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[30670.165171]  [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[30670.166323]  [<ffffffffa035daa7>] ? __btrfs_abort_transaction+0x52/0x106 [btrfs]
[30670.167213]  [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[30670.167862]  [<ffffffffa035daa7>] __btrfs_abort_transaction+0x52/0x106 [btrfs]
[30670.169116]  [<ffffffffa03743d7>] btrfs_create_pending_block_groups+0x101/0x130 [btrfs]
[30670.170593]  [<ffffffffa038426a>] __btrfs_end_transaction+0x84/0x366 [btrfs]
[30670.171960]  [<ffffffffa038455c>] btrfs_end_transaction+0x10/0x12 [btrfs]
[30670.174649]  [<ffffffffa036eb6b>] btrfs_check_data_free_space+0x11f/0x27c [btrfs]
[30670.176092]  [<ffffffffa039450d>] btrfs_fallocate+0x7c8/0xb96 [btrfs]
[30670.177218]  [<ffffffff812459f2>] ? __this_cpu_preempt_check+0x13/0x15
[30670.178622]  [<ffffffff81152447>] vfs_fallocate+0x14c/0x1de
[30670.179642]  [<ffffffff8116b915>] ? __fget_light+0x2d/0x4f
[30670.180692]  [<ffffffff81152863>] SyS_fallocate+0x47/0x62
[30670.186737]  [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[30670.187792] ---[ end trace 0373e6b491c4a8cc ]---

This is because we don't do proper space reservation for the chunk block
reserve when we have multiple tasks allocating chunks in parallel.

So block group creation has 2 phases, and the first phase essentially
checks if there is enough space in the system space_info, allocating a
new system chunk if there isn't, while the second phase updates the
device, extent and chunk trees. However, because the updates to the
chunk tree happen in the second phase, if we have N tasks, each with
its own transaction handle, allocating new chunks in parallel and if
there is only enough space in the system space_info to allocate M chunks,
where M < N, none of the tasks ends up allocating a new system chunk in
the first phase and N - M tasks will get -ENOSPC when attempting to
update the chunk tree in phase 2 if they need to COW any nodes/leafs
from the chunk tree.

Fix this by doing proper reservation in the chunk block reserve.

The issue could be reproduced by running fstests generic/038 in a loop,
which eventually triggered the problem.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:04 -07:00
Josef Bacik 0d2b2372e0 Btrfs: set UNWRITTEN for prealloc'ed extents in fiemap
We should be doing this, it's weird we hadn't been doing this.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:03 -07:00
Omar Sandoval c8d3fe028f Btrfs: show subvol= and subvolid= in /proc/mounts
Now that we're guaranteed to have a meaningful root dentry, we can just
export seq_dentry() and use it in btrfs_show_options(). The subvolume ID
is easy to get and can also be useful, so put that in there, too.

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:02 -07:00
Omar Sandoval 05dbe6837b Btrfs: unify subvol= and subvolid= mounting
Currently, mounting a subvolume with subvolid= takes a different code
path than mounting with subvol=. This isn't really a big deal except for
the fact that mounts done with subvolid= or the default subvolume don't
have a dentry that's connected to the dentry tree like in the subvol=
case. To unify the code paths, when given subvolid= or using the default
subvolume ID, translate it into a subvolume name by walking
ROOT_BACKREFs in the root tree and INODE_REFs in the filesystem trees.

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:01 -07:00
Omar Sandoval bb289b7be6 Btrfs: fail on mismatched subvol and subvolid mount options
There's nothing to stop a user from passing both subvol= and subvolid=
to mount, but if they don't refer to the same subvolume, someone is
going to be surprised at some point. Error out on this case, but allow
users to pass in both if they do match (which they could, for example,
get out of /proc/mounts).

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:03:00 -07:00
Omar Sandoval fa33065950 Btrfs: clean up error handling in mount_subvol()
In preparation for new functionality in mount_subvol(), give it
ownership of subvol_name and tidy up the error paths.

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:59 -07:00
Omar Sandoval e6e4dbe894 Btrfs: remove all subvol options before mounting top-level
Currently, setup_root_args() substitutes 's/subvol=[^,]*/subvolid=0/'.
But, this means that if the user passes both a subvol and subvolid for
some reason, we won't actually mount the top-level when we recursively
mount. For example, consider:

mkfs.btrfs -f /dev/sdb
mount /dev/sdb /mnt
btrfs subvol create /mnt/subvol1 # subvolid=257
btrfs subvol create /mnt/subvol2 # subvolid=258
umount /mnt
mount -osubvol=/subvol1,subvolid=258 /dev/sdb /mnt

In the final mount, subvol=/subvol1,subvolid=258 becomes
subvolid=0,subvolid=258, and the last option takes precedence, so we
mount subvol2 and try to look up subvol1 inside of it, which fails.

So, instead, do a thorough scan through the argument list and remove any
subvol= and subvolid= options, then append subvolid=0 to the end. This
implicitly makes subvol= take precedence over subvolid=, but we're about
to add a stricter check for that. This also makes setup_root_args() more
generic, which we'll need soon.

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:58 -07:00
Omar Sandoval 773cd04ec1 Btrfs: lock superblock before remounting for rw subvol
Since commit 0723a0473f ("btrfs: allow mounting btrfs subvolumes with
different ro/rw options"), when mounting a subvolume read/write when
another subvolume has previously been mounted read-only, we first do a
remount. However, this should be done with the superblock locked, as per
sync_filesystem():

	/*
	 * We need to be protected against the filesystem going from
	 * r/o to r/w or vice versa.
	 */
	WARN_ON(!rwsem_is_locked(&sb->s_umount));

This WARN_ON can easily be hit with:

mkfs.btrfs -f /dev/vdb
mount /dev/vdb /mnt
btrfs subvol create /mnt/vol1
btrfs subvol create /mnt/vol2
umount /mnt
mount -oro,subvol=/vol1 /dev/vdb /mnt
mount -orw,subvol=/vol2 /dev/vdb /mnt2

Fixes: 0723a0473f ("btrfs: allow mounting btrfs subvolumes with different ro/rw options")
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:57 -07:00
Filipe Manana 0f31871f44 Btrfs: wake up extent state waiters on unlock through clear_extent_bits
When we clear an extent state's EXTENT_LOCKED bit with clear_extent_bits()
through free_io_failure(), we weren't waking up any tasks waiting for the
extent's state EXTENT_LOCKED bit, leading to an hang.

So make sure clear_extent_bits() ends up waking up any waiters if the
bit EXTENT_LOCKED is supplied by its callers.

Zygo Blaxell was experiencing such hangs at inode eviction time after
file unlinks. Thanks to him for a set of scripts to reproduce the issue.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:56 -07:00
Filipe Manana c152b63efc Btrfs: fix chunk allocation regression leading to transaction abort
With commit 1b98450816 ("Btrfs: fix find_free_dev_extent() malfunction
in case device tree has hole") introduced in the kernel 4.1 merge window,
we end up using part of a device hole for which there are already pending
chunks or pinned chunks. Before that commit we didn't use the hole and
would just move on to the next hole in the device.

However when we adjust the start offset for the chunk allocation and we
have pinned chunks, we set it blindly to the end offset of the pinned
chunk we are currently processing, which is dangerous because we can
have a pending chunk that has a start offset that matches the end offset
of our pinned chunk - leading us to a case where we end up getting two
pending chunks that start at the same physical device offset, which makes
us later abort the current transaction with -EEXIST when finishing the
chunk allocation at btrfs_create_pending_block_groups():

[194737.659017] ------------[ cut here ]------------
[194737.660192] WARNING: CPU: 15 PID: 31111 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x106 [btrfs]()
[194737.662209] BTRFS: Transaction aborted (error -17)
[194737.663175] Modules linked in: btrfs dm_snapshot dm_bufio dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse
[194737.674015] CPU: 15 PID: 31111 Comm: xfs_io Tainted: G        W       4.0.0-rc5-btrfs-next-9+ #2
[194737.675986] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[194737.682999]  0000000000000009 ffff8800564c7a98 ffffffff8142fa46 ffffffff8108b6a2
[194737.684540]  ffff8800564c7ae8 ffff8800564c7ad8 ffffffff81045ea5 ffff8800564c7b78
[194737.686017]  ffffffffa0383aa7 00000000ffffffef ffff88000c7ba000 ffff8801a1f66f40
[194737.687509] Call Trace:
[194737.688068]  [<ffffffff8142fa46>] dump_stack+0x4f/0x7b
[194737.689027]  [<ffffffff8108b6a2>] ? console_unlock+0x361/0x3ad
[194737.690095]  [<ffffffff81045ea5>] warn_slowpath_common+0xa1/0xbb
[194737.691198]  [<ffffffffa0383aa7>] ? __btrfs_abort_transaction+0x52/0x106 [btrfs]
[194737.693789]  [<ffffffff81045f05>] warn_slowpath_fmt+0x46/0x48
[194737.695065]  [<ffffffffa0383aa7>] __btrfs_abort_transaction+0x52/0x106 [btrfs]
[194737.696806]  [<ffffffffa039a3bd>] btrfs_create_pending_block_groups+0x101/0x130 [btrfs]
[194737.698683]  [<ffffffffa03aa433>] __btrfs_end_transaction+0x84/0x366 [btrfs]
[194737.700329]  [<ffffffffa03aa725>] btrfs_end_transaction+0x10/0x12 [btrfs]
[194737.701924]  [<ffffffffa0394b51>] btrfs_check_data_free_space+0x11f/0x27c [btrfs]
[194737.703675]  [<ffffffffa03b8ba4>] __btrfs_buffered_write+0x16a/0x4c8 [btrfs]
[194737.705417]  [<ffffffffa03bb502>] ? btrfs_file_write_iter+0x19a/0x431 [btrfs]
[194737.707058]  [<ffffffffa03bb511>] ? btrfs_file_write_iter+0x1a9/0x431 [btrfs]
[194737.708560]  [<ffffffffa03bb68d>] btrfs_file_write_iter+0x325/0x431 [btrfs]
[194737.710673]  [<ffffffff81067d85>] ? get_parent_ip+0xe/0x3e
[194737.712076]  [<ffffffff811534c3>] new_sync_write+0x7c/0xa0
[194737.713293]  [<ffffffff81153b58>] vfs_write+0xb2/0x117
[194737.714443]  [<ffffffff81154424>] SyS_pwrite64+0x64/0x82
[194737.715646]  [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[194737.717175] ---[ end trace f2d5dc04e56d7e48 ]---
[194737.718170] BTRFS: error (device sdc) in btrfs_create_pending_block_groups:9524: errno=-17 Object already exists

The -EEXIST failure comes from btrfs_finish_chunk_alloc(), called by
btrfs_create_pending_block_groups(), when it attempts to insert a
duplicated device extent item via btrfs_alloc_dev_extent().

This issue was reproducible with fstests generic/038 running in a loop for
several hours (it's very hard to hit) and using MOUNT_OPTIONS="-o discard".
Applying Jeff's recent patch titled "btrfs: add missing discards when
unpinning extents with -o discard" makes the issue much easier to reproduce
(usually within 4 to 5 hours), since it pins chunks for longer periods of
time when an unused block group is deleted by the cleaner kthread.

Fix this by making sure that we never adjust the start offset to a lower
value than it currently has.

Fixes: 1b98450816 ("Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole"
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-03 04:02:55 -07:00
Sasha Levin 2037a0933b btrfs: use after free when closing devices
__btrfs_close_devices() would call_rcu to free the device, which is racy with
list_for_each_entry() accessing the memory to retrieve the next device on the
list.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:36 -07:00
David Sterba 01b810b889 btrfs: make root id query unprivileged
The INO_LOOKUP ioctl can lookup path for a given inode number and is
thus restricted. As a sideefect it can find the root id of the
containing subvolume and we're using this int the 'btrfs inspect rootid'
command.

The restriction is unnecessary in case we set the ioctl args
 args::treeid    = 0
 args::objectid  = 256 (BTRFS_FIRST_FREE_OBJECTID)

Then the path will be empty and the treeid is filled with the root id of
the inode on which the ioctl is called. This behaviour is unchanged,
after the root restriction is removed.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:36 -07:00
Filipe Manana 2e6e518335 Btrfs: fix block group ->space_info null pointer dereference
When we create a block group we add it to the rbtree of block groups
before setting its ->space_info field (while it's NULL). This is
problematic since other tasks can access the block group from the
rbtree and attempt to use its ->space_info before it is set by
btrfs_make_block_group().

This can happen for example when a concurrent fitrim ioctl operation
is ongoing, which produces a trace like the following when
CONFIG_DEBUG_PAGEALLOC is set.

[11509.604369] BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
[11509.606373] IP: [<ffffffff8107d675>] __lock_acquire+0xb4/0xf02
[11509.608179] PGD 2296a8067 PUD 22f4a2067 PMD 0
[11509.608179] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[11509.608179] Modules linked in: btrfs crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse acpi_cpufreq processor i2c_piix4 psmou
[11509.608179] CPU: 10 PID: 8538 Comm: fstrim Tainted: G        W       4.0.0-rc5-btrfs-next-9+ #2
[11509.608179] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
[11509.608179] task: ffff88009f5c46d0 ti: ffff8801b3edc000 task.ti: ffff8801b3edc000
[11509.608179] RIP: 0010:[<ffffffff8107d675>]  [<ffffffff8107d675>] __lock_acquire+0xb4/0xf02
[11509.608179] RSP: 0018:ffff8801b3edf9e8  EFLAGS: 00010002
[11509.608179] RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
[11509.608179] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000018
[11509.608179] RBP: ffff8801b3edfaa8 R08: 0000000000000001 R09: 0000000000000000
[11509.608179] R10: 0000000000000000 R11: ffff88009f5c4f98 R12: 0000000000000000
[11509.608179] R13: 0000000000000000 R14: 0000000000000018 R15: ffff88009f5c46d0
[11509.608179] FS:  00007f280a10e840(0000) GS:ffff88023ed40000(0000) knlGS:0000000000000000
[11509.608179] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[11509.608179] CR2: 0000000000000018 CR3: 00000002119bc000 CR4: 00000000000006e0
[11509.608179] Stack:
[11509.608179]  0000000000000000 0000000000000000 0000000000000004 0000000000000000
[11509.608179]  ffff880100000000 ffffffff00000000 0000000000000001 ffffffff00000000
[11509.608179]  0000000000000001 0000000000000000 ffff880100000000 00000000000006c4
[11509.608179] Call Trace:
[11509.608179]  [<ffffffff8107dc57>] ? __lock_acquire+0x696/0xf02
[11509.608179]  [<ffffffff8107e806>] lock_acquire+0xa5/0x116
[11509.608179]  [<ffffffffa04cc876>] ? do_trimming+0x51/0x145 [btrfs]
[11509.608179]  [<ffffffff81434f37>] _raw_spin_lock+0x34/0x44
[11509.608179]  [<ffffffffa04cc876>] ? do_trimming+0x51/0x145 [btrfs]
[11509.608179]  [<ffffffffa04cc876>] do_trimming+0x51/0x145 [btrfs]
[11509.608179]  [<ffffffffa04cde7d>] btrfs_trim_block_group+0x201/0x491 [btrfs]
[11509.608179]  [<ffffffffa04849e2>] btrfs_trim_fs+0xe0/0x129 [btrfs]
[11509.608179]  [<ffffffffa04bb80a>] btrfs_ioctl_fitrim+0x138/0x167 [btrfs]
[11509.608179]  [<ffffffffa04c002f>] btrfs_ioctl+0x50d/0x21e8 [btrfs]
[11509.608179]  [<ffffffff81123bda>] ? might_fault+0x58/0xb5
[11509.608179]  [<ffffffff81123bda>] ? might_fault+0x58/0xb5
[11509.608179]  [<ffffffff81123bda>] ? might_fault+0x58/0xb5
[11509.608179]  [<ffffffff81158050>] ? cp_new_stat+0x147/0x15e
[11509.608179]  [<ffffffff81163041>] do_vfs_ioctl+0x3c6/0x479
[11509.608179]  [<ffffffff81158116>] ? SYSC_newfstat+0x25/0x2e
[11509.608179]  [<ffffffff81435b54>] ? ret_from_sys_call+0x1d/0x58
[11509.608179]  [<ffffffff8116b915>] ? __fget_light+0x2d/0x4f
[11509.608179]  [<ffffffff8116314e>] SyS_ioctl+0x5a/0x7f
[11509.608179]  [<ffffffff81435b32>] system_call_fastpath+0x12/0x17
[11509.608179] Code: f4 01 00 0f 85 c0 00 00 00 48 c7 c1 f3 1f 7d 81 48 c7 c2 aa cb 7c 81 be fc 0b 00 00 eb 70 83 3d 61 eb 9c 00 00 0f 84 a5 00 00 00 <49> 81 3e 40 a3 2b 82 b8 00 00 00
[11509.608179] RIP  [<ffffffff8107d675>] __lock_acquire+0xb4/0xf02
[11509.608179]  RSP <ffff8801b3edf9e8>
[11509.608179] CR2: 0000000000000018
[11509.608179] ---[ end trace 570a5c6769f0e49a ]---

Which corresponds to the following access in fs/btrfs/free-space-cache.c:

  static int do_trimming(struct btrfs_block_group_cache *block_group,
                         u64 *total_trimmed, u64 start, u64 bytes,
                         u64 reserved_start, u64 reserved_bytes,
                         struct btrfs_trim_range *trim_entry)
  {
       struct btrfs_space_info *space_info = block_group->space_info;
  (...)
       spin_lock(&space_info->lock);
       ^^^^^ - block_group->space_info is NULL...

Fix this by ensuring the block group's ->space_info is set before adding
the block group to the rbtree.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:36 -07:00
Anand Jain 33b97e4327 Btrfs: check error before reporting missing device and add uuid
Report missing device when add is successful,
otherwise it would exit as ENOMEM. And add uuid
to the report.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Qu Wenruo 1f6e4b3f9f btrfs: Fix superblock csum type check.
Old csum type check is wrong and can't catch csum_type 1(not supported).

Fix it to avoid hostile 0 division.

Reported-by: Lukas Lueg <lukas.lueg@gmail.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Filipe Manana 619d8c4ef7 Btrfs: incremental send, fix clone operations for compressed extents
Marc reported a problem where the receiving end of an incremental send
was performing clone operations that failed with -EINVAL. This happened
because, unlike for uncompressed extents, we were not checking if the
source clone offset and length, after summing the data offset, falls
within the source file's boundaries.

So make sure we do such checks when attempting to issue clone operations
for compressed extents.

Problem reproducible with the following steps:

  $ mkfs.btrfs -f /dev/sdb
  $ mount -o compress /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount -o compress /dev/sdc /mnt2

  # Create the file with a single extent of 128K. This creates a metadata file
  # extent item with a data start offset of 0 and a logical length of 128K.
  $ xfs_io -f -c "pwrite -S 0xaa 64K 128K" -c "fsync" /mnt/foo

  # Now rewrite the range 64K to 112K of our file. This will make the inode's
  # metadata continue to point to the 128K extent we created before, but now
  # with an extent item that points to the extent with a data start offset of
  # 112K and a logical length of 16K.
  # That metadata file extent item is associated with the logical file offset
  # at 176K and covers the logical file range 176K to 192K.
  $ xfs_io -c "pwrite -S 0xbb 64K 112K" -c "fsync" /mnt/foo

  # Now rewrite the range 180K to 12K. This will make the inode's metadata
  # continue to point the the 128K extent we created earlier, with a single
  # extent item that points to it with a start offset of 112K and a logical
  # length of 4K.
  # That metadata file extent item is associated with the logical file offset
  # at 176K and covers the logical file range 176K to 180K.
  $ xfs_io -c "pwrite -S 0xcc 180K 12K" -c "fsync" /mnt/foo

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ touch /mnt/bar
  # Calls the btrfs clone ioctl.
  $ ~/xfstests/src/cloner -s $((176 * 1024)) -d $((176 * 1024)) \
    -l $((4 * 1024)) /mnt/foo /mnt/bar

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  At subvol /mnt/snap1
  At subvol snap1

  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
  At subvol /mnt/snap2
  At snapshot snap2
  ERROR: failed to clone extents to bar
  Invalid argument

A test case for fstests follows soon.

Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: David Sterba <dsterba@suse.cz>
Tested-by: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Christian Engelmayer ab3680dd18 btrfs: qgroup: Fix possible leak in btrfs_add_qgroup_relation()
Commit 9c8b35b1ba ("btrfs: quota: Automatically update related qgroups or
mark INCONSISTENT flags when assigning/deleting a qgroup relations.")
introduced the allocation of a temporary ulist in function
btrfs_add_qgroup_relation() and added the corresponding cleanup to the out
path. However, the allocation was introduced before the src/dst level check
that directly returns. Fix the possible leakage of the ulist by moving the
allocation after the input validation. Detected by Coverity CID 1295988.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Filipe Manana 35c766425a Btrfs: fix mutex unlock without prior lock on space cache truncation
If the call to btrfs_truncate_inode_items() failed and we don't have a block
group, we were unlocking the cache_write_mutex without having locked it (we
do it only if we have a block group).

Fixes: 1bbc621ef2 ("Btrfs: allow block group cache writeout
                      outside critical section in commit")

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
Anand Jain 816fcebe8f Btrfs: log when missing device is created
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
David Sterba 6d13f5497f btrfs: fix warnings after changes in btrfs_abort_transaction
fs/btrfs/volumes.c: In function ‘btrfs_create_uuid_tree’:
fs/btrfs/volumes.c:3909:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
   btrfs_abort_transaction(trans, tree_root,
   ^
  CC [M]  fs/btrfs/ioctl.o
fs/btrfs/ioctl.c: In function ‘create_subvol’:
fs/btrfs/ioctl.c:549:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
   btrfs_abort_transaction(trans, root, PTR_ERR(new_root));

PTR_ERR returns long, but we're really using 'int' for the error codes
everywhere so just set and use the local variable.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
David Sterba c0d19e2b9a btrfs: add 'cold' compiler annotations to all error handling functions
The annotated functios will be placed into .text.unlikely section. The
annotation also hints compiler to move the code out of the hot paths,
and may implicitly mark if-statement leading to that block as unlikely.

This is a heuristic, the impact on the generated code is not
significant.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
David Sterba 1a9a8a71ed btrfs: report exact callsite where transaction abort occurs
WARN is called from a single location and all bugreports say that's in
super.c __btrfs_abort_transaction. This is slightly confusing as we'd
rather want to know the exact callsite. Whereas this information is
printed in the syslog below the stacktrace, this requires further look
and we usually see only the headline from WARNING.

Moving the WARN into the macro has to inline some code and increases
code by a few kilobytes:

  text    data     bss     dec     hex filename
835481   20305   14120  869906   d4612 btrfs.ko.before
842883   20305   14120  877308   d62fc btrfs.ko.after

The delta is +7k (130+ calls), measured on 3.19 x86_64, distro config.
The increase is not small and could lead to worse icache use. The code
is on error/exit paths that can be recognized by compiler as cold and
moved out of the way so the impact is speculated to be low, if
measurable at all.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
David Sterba 13028901a4 btrfs: let tree defrag work in SSD mode
Long time ago (2008) the defrag was automatic for new b-tree writes but
has been disabled after performance problems. There was a leftover in
tree-defrag.c that effectively stops any defragmentation on b-trees.
This is a bit unexpected and IMHO undesired. The SSD mode is an
optimization and defrag is supposed to work if the users asks for it.

Related commits:

6702ed490c
Btrfs: Add run time btree defrag, and an ioctl to force btree defrag

e18e4809b1
Btrfs: Add mount -o ssd, which includes optimizations for seek free
storage

b3236e68bf
Btrfs: Leave on the tree defragger in mount -o ssd, it still helps there

9afbb0b752
Btrfs: Disable tree defrag in SSD mode

The last three commits switch the defrag+ssd off/on/off and the last one

3f157a2fd2
Btrfs: Online btree defragmentation fixes

misses the bits from tree-defrag.c to revert to the behaviour introduced
in e18e4809b1.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:33 -07:00
Filipe Manana 53e489bc8c Btrfs: check pending chunks when shrinking fs to avoid corruption
When we shrink the usable size of a device (its total_bytes), we go over
all the device extent items in the device tree and attempt to relocate
the chunk of any device extent that goes beyond the new usable size for
the device. We do that after setting the new usable size (total_bytes) in
the device object, so that all new allocations (and reallocations) don't
use areas of the device that go beyond the new (shorter) size. However we
were not considering that before setting the new size in the device,
pending chunks might have been created that use device extents that go
beyond the new size, and those device extents are not yet in the device
tree after we search the device tree - they are still attached to the
list of new block group for some ongoing transaction handle, and they are
only added to the device tree when the transaction handle is ended (via
btrfs_create_pending_block_groups()).

So check for pending chunks with device extents that go beyond the new
size and if any exists, commit the current transaction and repeat the
search in the device tree.

Not doing this it would mean we would return success to user space while
still having extents that go beyond the new size, and later user space
could override those locations on the device while the fs still references
them, causing all sorts of corruption and unexpected events.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:33 -07:00
Omar Sandoval 64ad6c4889 Btrfs: don't invalidate root dentry when subvolume deletion fails
Since commit bafc9b754f ("vfs: More precise tests in d_invalidate"),
mounted subvolumes can be deleted because d_invalidate() won't fail.
However, we run into problems when we attempt to delete the default
subvolume while it is mounted as the root filesystem:

	# btrfs subvol list /
	ID 257 gen 306 top level 5 path rootvol
	ID 267 gen 334 top level 5 path snap1
	# btrfs subvol get-default /
	ID 267 gen 334 top level 5 path snap1
	# btrfs inspect-internal rootid /
	267
	# mount -o subvol=/ /dev/vda1 /mnt
	# btrfs subvol del /mnt/snap1
	Delete subvolume (no-commit): '/mnt/snap1'
	ERROR: cannot delete '/mnt/snap1' - Operation not permitted
	# findmnt /
	findmnt: can't read /proc/mounts: No such file or directory
	# ls /proc
	#

Markus reported that this same scenario simply led to a kernel oops.

This happens because in btrfs_ioctl_snap_destroy(), we call
d_invalidate() before we check may_destroy_subvol(), which means that we
detach the submounts and drop the dentry before erroring out. Instead,
we should only invalidate the dentry once the deletion has succeeded.
Additionally, the shrink_dcache_sb() isn't necessary; d_invalidate()
will prune the dcache for the deleted subvolume.

Cc: <stable@vger.kernel.org>
Fixes: bafc9b754f ("vfs: More precise tests in d_invalidate")
Reported-by: Markus Schauler <mschauler@gmail.com>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:33 -07:00
Filipe Manana 8b191a6849 Btrfs: incremental send, check if orphanized dir inode needs delayed rename
If a directory inode is orphanized, because some inode previously
processed has a new name that collides with the old name of the current
inode, we need to check if it needs its rename operation delayed too,
as its ancestor-descendent relationship with some other inode might
have been reversed between the parent and send snapshots and therefore
its rename operation needs to happen after that other inode is renamed.

For example, for the following reproducer where this is needed (provided
by Robbie Ko):

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2

  $ mkdir -p /mnt/data/n1/n2
  $ mkdir /mnt/data/n4
  $ mkdir -p /mnt/data/t6/t7
  $ mkdir /mnt/data/t5
  $ mkdir /mnt/data/t7
  $ mkdir /mnt/data/n4/t2
  $ mkdir /mnt/data/t4
  $ mkdir /mnt/data/t3
  $ mv /mnt/data/t7 /mnt/data/n4/t2
  $ mv /mnt/data/t4 /mnt/data/n4/t2/t7
  $ mv /mnt/data/t5 /mnt/data/n4/t2/t7/t4
  $ mv /mnt/data/t6 /mnt/data/n4/t2/t7/t4/t5
  $ mv /mnt/data/n1/n2 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n1 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/t7 /mnt/data/n4/t2/t7/t4/t5/t6/n2
  $ mv /mnt/data/t3 /mnt/data/n4/t2/t7/t4/t5/t6/n2/t7

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/n1 /mnt/data/n4
  $ mv /mnt/data/n4/t2 /mnt/data/n4/n1
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6/n2 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/n2/t7/t3 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4 /mnt/data/n4/n1/t2/t6
  $ mv /mnt/data/n4/n1/t2/t7 /mnt/data/n4/n1/t2/t3
  $ mv /mnt/data/n4/n1/t2/n2/t7 /mnt/data/n4/n1/t2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
  ERROR: send ioctl failed with -12: Cannot allocate memory

Where the parent snapshot directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- t2/                                       (ino 265)
                  |-- t7/                                  (ino 264)
                       |-- t4/                             (ino 266)
                            |-- t5/                        (ino 263)
                                 |-- t6/                   (ino 261)
                                      |-- n1/              (ino 258)
                                      |-- n2/              (ino 259)
                                           |-- t7/         (ino 262)
                                                |-- t3/    (ino 267)

And the send snapshot's directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- n1/                                       (ino 258)
                  |-- t2/                                  (ino 265)
                       |-- n2/                             (ino 259)
                       |-- t3/                             (ino 267)
                       |    |-- t7                         (ino 264)
                       |
                       |-- t6/                             (ino 261)
                       |    |-- t4/                        (ino 266)
                       |         |-- t5/                   (ino 263)
                       |
                       |-- t7/                             (ino 262)

While processing inode 262 we orphanize inode 264 and later attempt
to rename inode 264 to its new name/location, which resulted in building
an incorrect destination path string for the rename operation with the
value "data/n4/t2/t7/t4/t5/t6/n2/t7/t3/t7". This rename operation must
have been done only after inode 267 is processed and renamed, as the
ancestor-descendent relationship between inodes 264 and 267 was reversed
between both snapshots, because otherwise it results in an infinite loop
when building the path string for inode 264 when we are processing an
inode with a number larger than 264. That loop is the following:

  start inode 264, send progress of 265 for example
  parent of 264 -> 267
  parent of 267 -> 262
  parent of 262 -> 259
  parent of 259 -> 261
  parent of 261 -> 263
  parent of 263 -> 266
  parent of 266 -> 264
    |--> back to first iteration while current path string length
         is <= PATH_MAX, and fail with -ENOMEM otherwise

So fix this by making the check if we need to delay a directory rename
regardless of the current inode having been orphanized or not.

A test case for fstests follows soon.

Thanks to Robbie Ko for providing a reproducer for this problem.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-06-03 03:10:40 +01:00
Filipe Manana 80aa602756 Btrfs: incremental send, don't delay directory renames unnecessarily
Even though we delay the rename of directories when they become
descendents of other directories that were also renamed in the send
root to prevent infinite path build loops, we were doing it in cases
where this was not needed and was actually harmful resulting in
infinite path build loops as we ended up with a circular dependency
of delayed directory renames.

Consider the following reproducer:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2

  $ mkdir /mnt/data
  $ mkdir /mnt/data/n1
  $ mkdir /mnt/data/n1/n2
  $ mkdir /mnt/data/n4
  $ mkdir /mnt/data/n1/n2/p1
  $ mkdir /mnt/data/n1/n2/p1/p2
  $ mkdir /mnt/data/t6
  $ mkdir /mnt/data/t7
  $ mkdir -p /mnt/data/t5/t7
  $ mkdir /mnt/data/t2
  $ mkdir /mnt/data/t4
  $ mkdir -p /mnt/data/t1/t3
  $ mkdir /mnt/data/p1
  $ mv /mnt/data/t1 /mnt/data/p1
  $ mkdir -p /mnt/data/p1/p2
  $ mv /mnt/data/t4 /mnt/data/p1/p2/t1
  $ mv /mnt/data/t5 /mnt/data/n4/t5
  $ mv /mnt/data/n1/n2/p1/p2 /mnt/data/n4/t5/p2
  $ mv /mnt/data/t7 /mnt/data/n4/t5/p2/t7
  $ mv /mnt/data/t2 /mnt/data/n4/t1
  $ mv /mnt/data/p1 /mnt/data/n4/t5/p2/p1
  $ mv /mnt/data/n1/n2 /mnt/data/n4/t5/p2/p1/p2/n2
  $ mv /mnt/data/n4/t5/p2/p1/p2/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1
  $ mv /mnt/data/n4/t5/t7 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7
  $ mv /mnt/data/n4/t5/p2/p1/t1/t3 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2/p1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1
  $ mv /mnt/data/t6 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t5
  $ mv /mnt/data/n4/t5/p2/p1/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t1
  $ mv /mnt/data/n1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/n1

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/n4/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/t1
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2/t1 /mnt/data/n4/
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2 /mnt/data/n4/t1/n2
  $ mv /mnt/data/n4/t1/t7/p1 /mnt/data/n4/t1/n2/p1
  $ mv /mnt/data/n4/t1/t3/t1 /mnt/data/n4/t1/n2/t1
  $ mv /mnt/data/n4/t1/t3 /mnt/data/n4/t1/n2/t1/t3
  $ mv /mnt/data/n4/t5/p2/p1/p2 /mnt/data/n4/t1/n2/p1/p2
  $ mv /mnt/data/n4/t1/t7 /mnt/data/n4/t1/n2/p1/t7
  $ mv /mnt/data/n4/t5/p2/p1 /mnt/data/n4/t1/n2/p1/p2/p1
  $ mv /mnt/data/n4/t1/n2/t1/t3/t5 /mnt/data/n4/t1/n2/p1/p2/t5
  $ mv /mnt/data/n4/t5 /mnt/data/n4/t1/n2/p1/p2/p1/t5
  $ mv /mnt/data/n4/t1/n2/p1/p2/p1/t5/p2 /mnt/data/n4/t1/n2/p1/p2/p1/p2
  $ mv /mnt/data/n4/t1/n2/p1/p2/p1/p2/t7 /mnt/data/n4/t1/t7

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive -vv /mnt2
  ERROR: send ioctl failed with -12: Cannot allocate memory

This reproducer resulted in an infinite path build loop when building the
path for inode 266 because the following circular dependency of delayed
directory renames was created:

   ino 272 <- ino 261 <- ino 259 <- ino 268 <- ino 267 <- ino 261

Where the notation "X <- Y" means the rename of inode X is delayed by the
rename of inode Y (X will be renamed after Y is renamed). This resulted
in an infinite path build loop of inode 266 because that inode has inode
261 as an ancestor in the send root and inode 261 is in the circular
dependency of delayed renames listed above.

Fix this by not delaying the rename of a directory inode if an ancestor of
the inode in the send root, which has a delayed rename operation, is not
also a descendent of the inode in the parent root.

Thanks to Robbie Ko for sending the reproducer example.
A test case for xfstests follows soon.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-06-03 03:10:20 +01:00
Jaegeuk Kim f56aa1c57e f2fs: fix to return exact trimmed size
Now, we add all the candidates for trim commands and then finally issue
discard commands.
So, we should count the trimmed size in back-end.

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-02 15:48:20 -07:00
Sasha Levin 161f873b89 vfs: read file_handle only once in handle_to_path
We used to read file_handle twice.  Once to get the amount of extra
bytes, and once to fetch the entire structure.

This may be problematic since we do size verifications only after the
first read, so if the number of extra bytes changes in userspace between
the first and second calls, we'll have an incoherent view of
file_handle.

Instead, read the constant size once, and copy that over to the final
structure without having to re-read it again.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-02 10:29:07 -07:00
Chao Yu f62185d0e2 f2fs: support FALLOC_FL_INSERT_RANGE
FALLOC_FL_INSERT_RANGE flag for ->fallocate was introduced in commit
dd46c78778 ("fs: Add support FALLOC_FL_INSERT_RANGE for fallocate").

The effect of FALLOC_FL_INSERT_RANGE command is the opposite of
FALLOC_FL_COLLAPSE_RANGE, if this command was performed, all data from
offset to EOF in our file will be shifted to right as given length, and
then range [offset, offset + length] becomes a hole.

This command is useful for our user who wants to add some data in the
middle of the file, for example: video/music editor will insert a keyframe
in specified position of media file, with this command we can easily create
a hole for inserting without removing original data.

This patch introduces f2fs_insert_range() to support FALLOC_FL_INSERT_RANGE.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Yuan Zhong <yuan.mark.zhong@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-02 09:53:27 -07:00
Chao Yu 528e34593d f2fs: hide common code in f2fs_replace_block
This patch clean up codes through:
1.rename f2fs_replace_block to __f2fs_replace_block().
2.introduce new f2fs_replace_block() to include __f2fs_replace_block()
and some common related codes around __f2fs_replace_block().

Then, newly introduced function f2fs_replace_block can be used by
following patch.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2015-06-02 09:52:07 -07:00
Abhi Das 9cde2898d0 gfs2: limit quota log messages
This patch makes the quota subsystem only report once that a
particular user/group has exceeded their allotted quota.

Previously, it was possible for a program to continuously try
exceeding quota (despite receiving EDQUOT) and in turn trigger
gfs2 to issue a kernel log message about quota exceed. In theory,
this could get out of hand and flood the log and the filesystem
hosting the log files.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-06-02 11:03:04 -05:00
Abhi Das 39a725803b gfs2: fix quota updates on block boundaries
For smaller block sizes (512B, 1K, 2K), some quotas straddle block
boundaries such that the usage value is on one block and the rest
of the quota is on the previous block. In such cases, the value
does not get updated correctly. This patch fixes that by addressing
the boundary conditions correctly.

This patch also adds a (s64) cast that was missing in a call to
gfs2_quota_change() in inode.c

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-06-02 11:02:24 -05:00
Jens Axboe d2e73fcceb buffer: remove unusued 'ret' variable
Merge hickup on my part, due to a clash between the writeback
changes and the EOPNOTSUPP removal in _submit_bh().

Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 09:22:34 -06:00
Tejun Heo e8a7abf5a5 writeback: disassociate inodes from dying bdi_writebacks
For the purpose of foreign inode detection, wb's (bdi_writeback's) are
identified by the associated memcg ID.  As we create a separate wb for
each memcg, this is enough to identify the active wb's; however, when
blkcg is enabled or disabled higher up in the hierarchy, the mapping
between memcg and blkcg changes which in turn creates a new wb to
service the new mapping.  The old wb is unlinked from index and
released after all references are drained.  The foreign inode
detection logic can't detect this condition because both the old and
new wb's point to the same memcg and thus never decides to move inodes
attached to the old wb to the new one.

This patch adds logic to initiate switching immediately in
wbc_attach_and_unlock_inode() if the associated wb is dying.  We can
make the usual foreign detection logic to distinguish the different
wb's mapped to the memcg but the dying wb is never gonna be in active
service again and there's no point in tracking the usage history and
reaching the switch verdict after enough data points are collected.
It's already known that the wb has to be switched.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo d10c809552 writeback: implement foreign cgroup inode bdi_writeback switching
As concurrent write sharing of an inode is expected to be very rare
and memcg only tracks page ownership on first-use basis severely
confining the usefulness of such sharing, cgroup writeback tracks
ownership per-inode.  While the support for concurrent write sharing
of an inode is deemed unnecessary, an inode being written to by
different cgroups at different points in time is a lot more common,
and, more importantly, charging only by first-use can too readily lead
to grossly incorrect behaviors (single foreign page can lead to
gigabytes of writeback to be incorrectly attributed).

To resolve this issue, cgroup writeback detects the majority dirtier
of an inode and transfers the ownership to it.  The previous patches
implemented the foreign condition detection mechanism and laid the
groundwork.  This patch implements the actual switching.

With the previously implemented [unlocked_]inode_to_wb_and_list_lock()
and wb stat transaction, grabbing wb->list_lock, inode->i_lock and
mapping->tree_lock gives us full exclusion against all wb operations
on the target inode.  inode_switch_wb_work_fn() grabs all the locks
and transfers the inode atomically along with its RECLAIMABLE and
WRITEBACK stats.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo aaa2cacf81 writeback: add lockdep annotation to inode_to_wb()
With the previous three patches, all operations which acquire wb from
inode are either under one of inode->i_lock, mapping->tree_lock or
wb->list_lock or protected by unlocked_inode_to_wb transaction.  This
will be depended upon by foreign inode wb switching.

This patch adds lockdep assertion to inode_to_wb() so that usages
outside the above list locks can be caught easily.  There are three
exceptions.

* locked_inode_to_wb_and_lock_list() is holding wb->list_lock but the
  wb may not be the inode's.  Ensuring that is the function's role
  after all.  Updated to deref inode->i_wb directly.

* inode_wb_stat_unlocked_begin() is usually protected by combination
  of !I_WB_SWITCH and rcu_read_lock().  Updated to deref inode->i_wb
  directly.

* inode_congested() wants to test whether inode->i_wb is set before
  starting the transaction.  Added inode_to_wb_is_valid() which tests
  inode->i_wb directly.

v5: might_lock() removed.  It annotates that the lock is grabbed w/
    irq enabled which isn't the case and triggering lockdep warning
    spuriously.

v4: might_lock() added to unlocked_inode_to_wb_begin().

v3: inode_congested() conversion added.

v2: locked_inode_to_wb_and_lock_list() was missing in the first
    version.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo 5cb8b8241e writeback: use unlocked_inode_to_wb transaction in inode_congested()
Similar to wb stat updates, inode_congested() accesses the associated
wb of an inode locklessly, which will break with foreign inode wb
switching.  This path updates inode_congested() to use unlocked inode
wb access transaction introduced by the previous patch.

Combined with the previous two patches, this makes all wb list and
access operations to be protected by either of inode->i_lock,
wb->list_lock, or mapping->tree_lock while wb switching is in
progress.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo 682aa8e1a6 writeback: implement unlocked_inode_to_wb transaction and use it for stat updates
The mechanism for detecting whether an inode should switch its wb
(bdi_writeback) association is now in place.  This patch build the
framework for the actual switching.

This patch adds a new inode flag I_WB_SWITCHING, which has two
functions.  First, the easy one, it ensures that there's only one
switching in progress for a give inode.  Second, it's used as a
mechanism to synchronize wb stat updates.

The two stats, WB_RECLAIMABLE and WB_WRITEBACK, aren't event counters
but track the current number of dirty pages and pages under writeback
respectively.  As such, when an inode is moved from one wb to another,
the inode's portion of those stats have to be transferred together;
unfortunately, this is a bit tricky as those stat updates are percpu
operations which are performed without holding any lock in some
places.

This patch solves the problem in a similar way as memcg.  Each such
lockless stat updates are wrapped in transaction surrounded by
unlocked_inode_to_wb_begin/end().  During normal operation, they map
to rcu_read_lock/unlock(); however, if I_WB_SWITCHING is asserted,
mapping->tree_lock is grabbed across the transaction.

In turn, the switching path sets I_WB_SWITCHING and waits for a RCU
grace period to pass before actually starting to switch, which
guarantees that all stat update paths are synchronizing against
mapping->tree_lock.

This patch still doesn't implement the actual switching.

v3: Updated on top of the recent cancel_dirty_page() updates.
    unlocked_inode_to_wb_begin() now nests inside
    mem_cgroup_begin_page_stat() to match the locking order.

v2: The i_wb access transaction will be used for !stat accesses too.
    Function names and comments updated accordingly.

    s/inode_wb_stat_unlocked_{begin|end}/unlocked_inode_to_wb_{begin|end}/
    s/switch_wb/switch_wbs/

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo 87e1d789bf writeback: implement [locked_]inode_to_wb_and_lock_list()
cgroup writeback currently assumes that inode to wb association
doesn't change; however, with the planned foreign inode wb switching
mechanism, the association will change dynamically.

When an inode needs to be put on one of the IO lists of its wb, the
current code simply calls inode_to_wb() and locks the returned wb;
however, with the planned wb switching, the association may change
before locking the wb and may even get released.

This patch implements [locked_]inode_to_wb_and_lock_list() which pins
the associated wb while holding i_lock, releases it, acquires
wb->list_lock and verifies that the association hasn't changed
inbetween.  As the association will be protected by both locks among
other things, this guarantees that the wb is the inode's associated wb
until the list_lock is released.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo 2a81490811 writeback: implement foreign cgroup inode detection
As concurrent write sharing of an inode is expected to be very rare
and memcg only tracks page ownership on first-use basis severely
confining the usefulness of such sharing, cgroup writeback tracks
ownership per-inode.  While the support for concurrent write sharing
of an inode is deemed unnecessary, an inode being written to by
different cgroups at different points in time is a lot more common,
and, more importantly, charging only by first-use can too readily lead
to grossly incorrect behaviors (single foreign page can lead to
gigabytes of writeback to be incorrectly attributed).

To resolve this issue, cgroup writeback detects the majority dirtier
of an inode and will transfer the ownership to it.  To avoid
unnnecessary oscillation, the detection mechanism keeps track of
history and gives out the switch verdict only if the foreign usage
pattern is stable over a certain amount of time and/or writeback
attempts.

The detection mechanism has fairly low space and computation overhead.
It adds 8 bytes to struct inode (one int and two u16's) and minimal
amount of calculation per IO.  The detection mechanism converges to
the correct answer usually in several seconds of IO time when there's
a clear majority dirtier.  Even when there isn't, it can reach an
acceptable answer fairly quickly under most circumstances.

Please see wb_detach_inode() for more details.

This patch only implements detection.  Following patches will
implement actual switching.

v2: wbc_account_io() now checks whether the wbc is associated with a
    wb before dereferencing it.  This can happen when pageout() is
    writing pages directly without going through the usual writeback
    path.  As pageout() path is single-threaded, we don't want it to
    be blocked behind a slow cgroup and ultimately want it to delegate
    actual writing to the usual writeback path.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:40:20 -06:00
Tejun Heo b16b1deb55 writeback: make writeback_control track the inode being written back
Currently, for cgroup writeback, the IO submission paths directly
associate the bio's with the blkcg from inode_to_wb_blkcg_css();
however, it'd be necessary to keep more writeback context to implement
foreign inode writeback detection.  wbc (writeback_control) is the
natural fit for the extra context - it persists throughout the
writeback of each inode and is passed all the way down to IO
submission paths.

This patch adds wbc_attach_and_unlock_inode(), wbc_detach_inode(), and
wbc_attach_fdatawrite_inode() which are used to associate wbc with the
inode being written back.  IO submission paths now use wbc_init_bio()
instead of directly associating bio's with blkcg themselves.  This
leaves inode_to_wb_blkcg_css() w/o any user.  The function is removed.

wbc currently only tracks the associated wb (bdi_writeback).  Future
patches will add more for foreign inode detection.  The association is
established under i_lock which will be depended upon when migrating
foreign inodes to other wb's.

As currently, once established, inode to wb association never changes,
going through wbc when initializing bio's doesn't cause any behavior
changes.

v2: submit_blk_blkcg() now checks whether the wbc is associated with a
    wb before dereferencing it.  This can happen when pageout() is
    writing pages directly without going through the usual writeback
    path.  As pageout() path is single-threaded, we don't want it to
    be blocked behind a slow cgroup and ultimately want it to delegate
    actual writing to the usual writeback path.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:39:48 -06:00
Tejun Heo 21c6321fbb writeback: relocate wb[_try]_get(), wb_put(), inode_{attach|detach}_wb()
Currently, majority of cgroup writeback support including all the
above functions are implemented in include/linux/backing-dev.h and
mm/backing-dev.c; however, the portion closely related to writeback
logic implemented in include/linux/writeback.h and mm/page-writeback.c
will expand to support foreign writeback detection and correction.

This patch moves wb[_try]_get() and wb_put() to
include/linux/backing-dev-defs.h so that they can be used from
writeback.h and inode_{attach|detach}_wb() to writeback.h and
page-writeback.c.

This is pure reorganization and doesn't introduce any functional
changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:39:08 -06:00
Tejun Heo aa661bbe1e writeback: move over_bground_thresh() to mm/page-writeback.c
and rename it to wb_over_bg_thresh().  The function is closely tied to
the dirty throttling mechanism implemented in page-writeback.c.  This
relocation will allow future updates necessary for cgroup writeback
support.

While at it, add function comment.

This is pure reorganization and doesn't introduce any behavioral
changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:13 -06:00
Tejun Heo dcc25ae76e writeback: move global_dirty_limit into wb_domain
This patch is a part of the series to define wb_domain which
represents a domain that wb's (bdi_writeback's) belong to and are
measured against each other in.  This will enable IO backpressure
propagation for cgroup writeback.

global_dirty_limit exists to regulate the global dirty threshold which
is a property of the wb_domain.  This patch moves hard_dirty_limit,
dirty_lock, and update_time into wb_domain.

This is pure reorganization and doesn't introduce any behavioral
changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:12 -06:00
Tejun Heo 8a73179956 writeback: reorganize [__]wb_update_bandwidth()
__wb_update_bandwidth() is called from two places -
fs/fs-writeback.c::balance_dirty_pages() and
mm/page-writeback.c::wb_writeback().  The latter updates only the
write bandwidth while the former also deals with the dirty ratelimit.
The two callsites are distinguished by whether @thresh parameter is
zero or not, which is cryptic.  In addition, the two files define
their own different versions of wb_update_bandwidth() on top of
__wb_update_bandwidth(), which is confusing to say the least.  This
patch cleans up [__]wb_update_bandwidth() in the following ways.

* __wb_update_bandwidth() now takes explicit @update_ratelimit
  parameter to gate dirty ratelimit handling.

* mm/page-writeback.c::wb_update_bandwidth() is flattened into its
  caller - balance_dirty_pages().

* fs/fs-writeback.c::wb_update_bandwidth() is moved to
  mm/page-writeback.c and __wb_update_bandwidth() is made static.

* While at it, add a lockdep assertion to __wb_update_bandwidth().

Except for the lockdep addition, this is pure reorganization and
doesn't introduce any behavioral changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:12 -06:00
Tejun Heo 0d960a383a writeback: clean up wb_dirty_limit()
The function name wb_dirty_limit(), its argument @dirty and the local
variable @wb_dirty are mortally confusing given that the function
calculates per-wb threshold value not dirty pages, especially given
that @dirty and @wb_dirty are used elsewhere for dirty pages.

Let's rename the function to wb_calc_thresh() and wb_dirty to
wb_thresh.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:12 -06:00
Tejun Heo 108dad65be ext2: enable cgroup writeback support
Writeback now supports cgroup writeback and the generic writeback,
buffer, libfs, and mpage helpers that ext2 uses are all updated to
work with cgroup writeback.

This patch enables cgroup writeback for ext2 by adding
FS_CGROUP_WRITEBACK to its ->fs_flags.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-ext4@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:04 -06:00
Tejun Heo 429b3fb027 mpage: make __mpage_writepage() honor cgroup writeback
__mpage_writepage() is used to implement mpage_writepages() which in
turn is used for ->writepages() of various filesystems.  All writeback
logic is now updated to handle cgroup writeback and the block cgroup
to issue IOs for is encoded in writeback_control and can be retrieved
from the inode; however, __mpage_writepage() currently ignores the
blkcg indicated by the inode and issues all bio's without explicit
blkcg association.

This patch updates __mpage_writepage() so that the issued bio's are
associated with inode_to_writeback_blkcg_css(inode).

v2: Updated for per-inode wb association.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:38:04 -06:00
Tejun Heo bafc0dba1e buffer, writeback: make __block_write_full_page() honor cgroup writeback
[__]block_write_full_page() is used to implement ->writepage in
various filesystems.  All writeback logic is now updated to handle
cgroup writeback and the block cgroup to issue IOs for is encoded in
writeback_control and can be retrieved from the inode; however,
[__]block_write_full_page() currently ignores the blkcg indicated by
inode and issues all bio's without explicit blkcg association.

This patch adds submit_bh_blkcg() which associates the bio with the
specified blkio cgroup before issuing and uses it in
__block_write_full_page() so that the issued bio's are associated with
inode_to_wb_blkcg_css(inode).

v2: Updated for per-inode wb association.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:37:23 -06:00
Tejun Heo 0747259d13 writeback: dirty inodes against their matching cgroup bdi_writeback's
__mark_inode_dirty() always dirtied the inode against the root wb
(bdi_writeback).  The previous patches added all the infrastructure
necessary to attribute an inode against the wb of the dirtying cgroup.

This patch updates __mark_inode_dirty() so that it uses the wb
associated with the inode instead of unconditionally using the root
one.

Currently, none of the filesystems has FS_CGROUP_WRITEBACK and all
pages will keep being dirtied against the root wb.

v2: Updated for per-inode wb association.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:37 -06:00
Tejun Heo db12536040 writeback: make writeback initiation functions handle multiple bdi_writeback's
[try_]writeback_inodes_sb[_nr]() and sync_inodes_sb() currently only
handle dirty inodes on the root wb (bdi_writeback) of the target bdi.
This patch implements bdi_split_work_to_wbs() and use it to make these
functions handle multiple wb's.

bdi_split_work_to_wbs() takes a base wb_writeback_work and create
clones of it and issue them to the wb's of the target bdi.  The base
work's nr_pages is distributed using wb_split_bdi_pages() -
ie. according to each wb's write bandwidth's proportion in the bdi.

Cloning a bdi involves memory allocation which may fail.  In such
cases, bdi_split_work_to_wbs() issues the base work directly and waits
for its completion before proceeding to the next wb to guarantee
forward progress and correctness under memory pressure.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:37 -06:00
Tejun Heo f30a7d0cc8 writeback: restructure try_writeback_inodes_sb[_nr]()
try_writeback_inodes_sb_nr() wraps writeback_inodes_sb_nr() so that it
handles s_umount locking and skips if writeback is already in
progress.  The in progress test is performed on the root wb
(bdi_writeback) which isn't sufficient for cgroup writeback support.
The test must be done per-wb.

To prepare for the change, this patch factors out
__writeback_inodes_sb_nr() from writeback_inodes_sb_nr() and adds
@skip_if_busy and moves the in progress test right before queueing the
wb_writeback_work.  try_writeback_inodes_sb_nr() now just grabs
s_umount and invokes __writeback_inodes_sb_nr() with asserted
@skip_if_busy.  This way, later addition of multiple wb handling can
skip only the wb's which already have writeback in progress.

This swaps the order between in progress test and s_umount test which
can flip the return value when writeback is in progress and s_umount
is being held by someone else but this shouldn't cause any meaningful
difference.  It's a fringe condition and the return value is an
unsynchronized hint anyway.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo 98754bf770 writeback: implement wb_wait_for_single_work()
For cgroup writeback, multiple wb_writeback_work items may need to be
issuedto accomplish a single task.  The previous patch updated the
waiting mechanism such that wb_wait_for_completion() can wait for
multiple work items.

Issuing mulitple work items involves memory allocation which may fail.
As most writeback operations can't fail or blocked on memory
allocation, in such cases, we'll fall back to sequential issuing of an
on-stack work item, which would need to be waited upon sequentially.

This patch implements wb_wait_for_single_work() which waits for a
single work item independently from wb_completion waiting so that such
fallback mechanism can be used without getting tangled with the usual
issuing / completion operation.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo cc395d7f1f writeback: implement bdi_wait_for_completion()
If the completion of a wb_writeback_work can be waited upon by setting
its ->done to a struct completion and waiting on it; however, for
cgroup writeback support, it's necessary to issue multiple work items
to multiple bdi_writebacks and wait for the completion of all.

This patch implements wb_completion which can wait for multiple work
items and replaces the struct completion with it.  It can be defined
using DEFINE_WB_COMPLETION_ONSTACK(), used for multiple work items and
waited for by wb_wait_for_completion().

Nobody currently issues multiple work items and this patch doesn't
introduce any behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo ac7b19a34f writeback: add wb_writeback_work->auto_free
Currently, a wb_writeback_work is freed automatically on completion if
it doesn't have ->done set.  Add wb_writeback_work->auto_free to make
the switch explicit.  This will help cgroup writeback support where
waiting for completion and whether to free automatically don't
necessarily move together.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo 001fe6f617 writeback: make wakeup_dirtytime_writeback() handle multiple bdi_writeback's
wakeup_dirtytime_writeback() currently only starts writeback on the
root wb (bdi_writeback).  For cgroup writeback support, update the
function to check all wbs.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo f2b6512160 writeback: make wakeup_flusher_threads() handle multiple bdi_writeback's
wakeup_flusher_threads() currently only starts writeback on the root
wb (bdi_writeback).  For cgroup writeback support, update the function
to wake up all wbs and distribute the number of pages to write
according to the proportion of each wb's write bandwidth, which is
implemented in wb_split_bdi_pages().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo 9ecf4866c0 writeback: make bdi_start_background_writeback() take bdi_writeback instead of backing_dev_info
bdi_start_background_writeback() currently takes @bdi and kicks the
root wb (bdi_writeback).  In preparation for cgroup writeback support,
make it take wb instead.

This patch doesn't make any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo bc05873dcc writeback: make writeback_in_progress() take bdi_writeback instead of backing_dev_info
writeback_in_progress() currently takes @bdi and returns whether
writeback is in progress on its root wb (bdi_writeback).  In
preparation for cgroup writeback support, make it take wb instead.
While at it, make it an inline function.

This patch doesn't make any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo c00ddad39f writeback: remove bdi_start_writeback()
bdi_start_writeback() is a thin wrapper on top of
__wb_start_writeback() which is used only by laptop_mode_timer_fn().
This patches removes bdi_start_writeback(), renames
__wb_start_writeback() to wb_start_writeback() and makes
laptop_mode_timer_fn() use it instead.

This doesn't cause any functional difference and will ease making
laptop_mode_timer_fn() cgroup writeback aware.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo e79729123f writeback: don't issue wb_writeback_work if clean
There are several places in fs/fs-writeback.c which queues
wb_writeback_work without checking whether the target wb
(bdi_writeback) has dirty inodes or not.  The only thing
wb_writeback_work does is writing back the dirty inodes for the target
wb and queueing a work item for a clean wb is essentially noop.  There
are some side effects such as bandwidth stats being updated and
triggering tracepoints but these don't affect the operation in any
meaningful way.

This patch makes all writeback_inodes_sb_nr() and sync_inodes_sb()
skip wb_queue_work() if the target bdi is clean.  Also, it moves
dirtiness check from wakeup_flusher_threads() to
__wb_start_writeback() so that all its callers benefit from the check.

While the overhead incurred by scheduling a noop work isn't currently
significant, the overhead may be higher with cgroup writeback support
as we may end up issuing noop work items to a lot of clean wb's.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo 95a46c65e3 writeback: make bdi_has_dirty_io() take multiple bdi_writeback's into account
bdi_has_dirty_io() used to only reflect whether the root wb
(bdi_writeback) has dirty inodes.  For cgroup writeback support, it
needs to take all active wb's into account.  If any wb on the bdi has
dirty inodes, bdi_has_dirty_io() should return true.

To achieve that, as inode_wb_list_{move|del}_locked() now keep track
of the dirty state transition of each wb, the number of dirty wbs can
be counted in the bdi; however, bdi is already aggregating
wb->avg_write_bandwidth which can easily be guaranteed to be > 0 when
there are any dirty inodes by ensuring wb->avg_write_bandwidth can't
dip below 1.  bdi_has_dirty_io() can simply test whether
bdi->tot_write_bandwidth is zero or not.

While this bumps the value of wb->avg_write_bandwidth to one when it
used to be zero, this shouldn't cause any meaningful behavior
difference.

bdi_has_dirty_io() is made an inline function which tests whether
->tot_write_bandwidth is non-zero.  Also, WARN_ON_ONCE()'s on its
value are added to inode_wb_list_{move|del}_locked().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:36 -06:00
Tejun Heo 766a9d6e60 writeback: implement backing_dev_info->tot_write_bandwidth
cgroup writeback support needs to keep track of the sum of
avg_write_bandwidth of all wb's (bdi_writeback's) with dirty inodes to
distribute write workload.  This patch adds bdi->tot_write_bandwidth
and updates inode_wb_list_move_locked(), inode_wb_list_del_locked()
and wb_update_write_bandwidth() to adjust it as wb's gain and lose
dirty inodes and its avg_write_bandwidth gets updated.

As the update events are not synchronized with each other,
bdi->tot_write_bandwidth is an atomic_long_t.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:35 -06:00
Tejun Heo d6c10f1fc8 writeback: implement WB_has_dirty_io wb_state flag
Currently, wb_has_dirty_io() determines whether a wb (bdi_writeback)
has any dirty inode by testing all three IO lists on each invocation
without actively keeping track.  For cgroup writeback support, a
single bdi will host multiple wb's each of which will host dirty
inodes separately and we'll need to make bdi_has_dirty_io(), which
currently only represents the root wb, aggregate has_dirty_io from all
member wb's, which requires tracking transitions in has_dirty_io state
on each wb.

This patch introduces inode_wb_list_{move|del}_locked() to consolidate
IO list operations leaving queue_io() the only other function which
directly manipulates IO lists (via move_expired_inodes()).  All three
functions are updated to call wb_io_lists_[de]populated() which keep
track of whether the wb has dirty inodes or not and record it using
the new WB_has_dirty_io flag.  inode_wb_list_moved_locked()'s return
value indicates whether the wb had no dirty inodes before.

mark_inode_dirty() is restructured so that the return value of
inode_wb_list_move_locked() can be used for deciding whether to wake
up the wb.

While at it, change {bdi|wb}_has_dirty_io()'s return values to bool.
These functions were returning 0 and 1 before.  Also, add a comment
explaining the synchronization of wb_state flags.

v2: Updated to accommodate b_dirty_time.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:35 -06:00
Tejun Heo 703c270887 writeback: implement and use inode_congested()
In several places, bdi_congested() and its wrappers are used to
determine whether more IOs should be issued.  With cgroup writeback
support, this question can't be answered solely based on the bdi
(backing_dev_info).  It's dependent on whether the filesystem and bdi
support cgroup writeback and the blkcg the inode is associated with.

This patch implements inode_congested() and its wrappers which take
@inode and determines the congestion state considering cgroup
writeback.  The new functions replace bdi_*congested() calls in places
where the query is about specific inode and task.

There are several filesystem users which also fit this criteria but
they should be updated when each filesystem implements cgroup
writeback support.

v2: Now that a given inode is associated with only one wb, congestion
    state can be determined independent from the asking task.  Drop
    @task.  Spotted by Vivek.  Also, converted to take @inode instead
    of @mapping and renamed to inode_congested().

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:35 -06:00
Tejun Heo 52ebea749a writeback: make backing_dev_info host cgroup-specific bdi_writebacks
For the planned cgroup writeback support, on each bdi
(backing_dev_info), each memcg will be served by a separate wb
(bdi_writeback).  This patch updates bdi so that a bdi can host
multiple wbs (bdi_writebacks).

On the default hierarchy, blkcg implicitly enables memcg.  This allows
using memcg's page ownership for attributing writeback IOs, and every
memcg - blkcg combination can be served by its own wb by assigning a
dedicated wb to each memcg.  This means that there may be multiple
wb's of a bdi mapped to the same blkcg.  As congested state is per
blkcg - bdi combination, those wb's should share the same congested
state.  This is achieved by tracking congested state via
bdi_writeback_congested structs which are keyed by blkcg.

bdi->wb remains unchanged and will keep serving the root cgroup.
cgwb's (cgroup wb's) for non-root cgroups are created on-demand or
looked up while dirtying an inode according to the memcg of the page
being dirtied or current task.  Each cgwb is indexed on bdi->cgwb_tree
by its memcg id.  Once an inode is associated with its wb, it can be
retrieved using inode_to_wb().

Currently, none of the filesystems has FS_CGROUP_WRITEBACK and all
pages will keep being associated with bdi->wb.

v3: inode_attach_wb() in account_page_dirtied() moved inside
    mapping_cap_account_dirty() block where it's known to be !NULL.
    Also, an unnecessary NULL check before kfree() removed.  Both
    detected by the kbuild bot.

v2: Updated so that wb association is per inode and wb is per memcg
    rather than blkcg.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: kbuild test robot <fengguang.wu@intel.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:35 -06:00
Tejun Heo a212b105b0 bdi: make inode_to_bdi() inline
Now that bdi definitions are moved to backing-dev-defs.h,
backing-dev.h can include blkdev.h and inline inode_to_bdi() without
worrying about introducing circular include dependency.  The function
gets called from hot paths and fairly trivial.

This patch makes inode_to_bdi() and sb_is_blkdev_sb() that the
function calls inline.  blockdev_superblock and noop_backing_dev_info
are EXPORT_GPL'd to allow the inline functions to be used from
modules.

While at it, make sb_is_blkdev_sb() return bool instead of int.

v2: Fixed typo in description as suggested by Jan.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:34 -06:00
Tejun Heo 66114cad64 writeback: separate out include/linux/backing-dev-defs.h
With the planned cgroup writeback support, backing-dev related
declarations will be more widely used across block and cgroup;
unfortunately, including backing-dev.h from include/linux/blkdev.h
makes cyclic include dependency quite likely.

This patch separates out backing-dev-defs.h which only has the
essential definitions and updates blkdev.h to include it.  c files
which need access to more backing-dev details now include
backing-dev.h directly.  This takes backing-dev.h off the common
include dependency chain making it a lot easier to use it across block
and cgroup.

v2: fs/fat build failure fixed.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:34 -06:00
Tejun Heo f0054bb1e1 writeback: move backing_dev_info->wb_lock and ->worklist into bdi_writeback
Currently, a bdi (backing_dev_info) embeds single wb (bdi_writeback)
and the role of the separation is unclear.  For cgroup support for
writeback IOs, a bdi will be updated to host multiple wb's where each
wb serves writeback IOs of a different cgroup on the bdi.  To achieve
that, a wb should carry all states necessary for servicing writeback
IOs for a cgroup independently.

This patch moves bdi->wb_lock and ->worklist into wb.

* The lock protects bdi->worklist and bdi->wb.dwork scheduling.  While
  moving, rename it to wb->work_lock as wb->wb_lock is confusing.
  Also, move wb->dwork downwards so that it's colocated with the new
  ->work_lock and ->work_list fields.

* bdi_writeback_workfn()		-> wb_workfn()
  bdi_wakeup_thread_delayed(bdi)	-> wb_wakeup_delayed(wb)
  bdi_wakeup_thread(bdi)		-> wb_wakeup(wb)
  bdi_queue_work(bdi, ...)		-> wb_queue_work(wb, ...)
  __bdi_start_writeback(bdi, ...)	-> __wb_start_writeback(wb, ...)
  get_next_work_item(bdi)		-> get_next_work_item(wb)

* bdi_wb_shutdown() is renamed to wb_shutdown() and now takes @wb.
  The function contained parts which belong to the containing bdi
  rather than the wb itself - testing cap_writeback_dirty and
  bdi_remove_from_list() invocation.  Those are moved to
  bdi_unregister().

* bdi_wb_{init|exit}() are renamed to wb_{init|exit}().
  Initializations of the moved bdi->wb_lock and ->work_list are
  relocated from bdi_init() to wb_init().

* As there's still only one bdi_writeback per backing_dev_info, all
  uses of bdi->state are mechanically replaced with bdi->wb.state
  introducing no behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-06-02 08:33:34 -06:00