Commit Graph

42702 Commits

Author SHA1 Message Date
Chris Mason
511711af91 btrfs: don't run delayed references while we are creating the free space tree
This is a short term solution to make sure btrfs_run_delayed_refs()
doesn't change the extent tree while we are scanning it to create the
free space tree.

Longer term we need to synchronize scanning the block groups one by one,
similar to what happens during a balance.

Signed-off-by: Chris Mason <clm@fb.com>
2015-12-30 07:52:35 -08:00
Chris Mason
b4570aa994 btrfs: fix compiling with CONFIG_BTRFS_DEBUG enabled.
Merging in the free space tree deleted a variable needed when
CONFIG_BTRFS_DEBUG=y

Signed-off-by: Chris Mason <clm@fb.com>
2015-12-30 07:37:26 -08:00
Chris Mason
140e639f1a btrfs: fix warning on uninit variable in btrfs_finish_chunk_alloc
map->num_stripes really can't be zero, but just in case.

Signed-off-by: Chris Mason <clm@fb.com>
2015-12-23 13:30:51 -08:00
Chris Mason
f0f76413d3 Merge branch 'freespace-4.5' into for-linus-4.5 2015-12-23 13:29:09 -08:00
Chris Mason
a53fe25769 Merge branch 'for-chris-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.5 2015-12-23 13:28:35 -08:00
Chris Mason
bb9d687618 Merge branch 'dev/simplify-set-bit' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-23 13:17:42 -08:00
Chris Mason
13d5d15d63 Merge branch 'dev/gfp-flags' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5 2015-12-23 13:11:27 -08:00
Chris Mason
afa427cf9d Merge branch 'cleanup/misc-simplify' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5 2015-12-23 13:10:26 -08:00
Filipe Manana
e44081ef61 Btrfs: fix unprotected list operations at btrfs_write_dirty_block_groups
We call btrfs_write_dirty_block_groups() in the critical section of a
transaction's commit, when no other tasks can join the transaction and
add more block groups to the transaction's list of dirty block groups,
so we not taking the dirty block groups spinlock when checking for the
list's emptyness, grabbing its first element or deleting elements from
it.

However there's a special and rare case where we can have a concurrent
task adding elements to this list. We trigger writeback for space
caches before at btrfs_start_dirty_block_groups() and in past iterations
of the loop at btrfs_write_dirty_block_groups(), this means that when
the writeback finishes (which happens asynchronously) it creates a
task for the endio free space work queue that executes
btrfs_finish_ordered_io() - this function is able to join the transaction,
through btrfs_join_transaction_nolock(), and update the free space cache's
inode item in the root tree, which can result in COWing nodes of this tree
and therefore allocation of a new block group can happen, which gets added
to the transaction's list of dirty block groups while the transaction
commit task is operating on it concurrently.

So fix this by taking the dirty block groups spinlock before doing
operations on the dirty block groups list at
btrfs_write_dirty_block_groups().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-21 17:51:22 +00:00
Linus Torvalds
fc315e3e5c Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "A couple of small fixes"

* 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: check prepare_uptodate_page() error code earlier
  Btrfs: check for empty bitmap list in setup_cluster_bitmaps
  btrfs: fix misleading warning when space cache failed to load
  Btrfs: fix transaction handle leak in balance
  Btrfs: fix unprotected list move from unused_bgs to deleted_bgs list
2015-12-18 15:35:08 -08:00
Colin Ian King
41a0c249cb proc: fix -ESRCH error when writing to /proc/$pid/coredump_filter
Writing to /proc/$pid/coredump_filter always returns -ESRCH because commit
774636e19e ("proc: convert to kstrto*()/kstrto*_from_user()") removed
the setting of ret after the get_proc_task call and incorrectly left it as
-ESRCH.  Instead, return 0 when successful.

Example breakage:

  echo 0 > /proc/self/coredump_filter
  bash: echo: write error: No such process

Fixes: 774636e19e ("proc: convert to kstrto*()/kstrto*_from_user()")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org> [4.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-18 14:25:40 -08:00
Chris Mason
f7d3d2f99e Merge branch 'freespace-tree' into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-18 11:11:10 -08:00
Filipe Manana
0376374a98 Btrfs: fix locking bugs when defragging leaves
When running fstests btrfs/070, with a higher number of fsstress
operations, I ran frequently into two different locking bugs when
defragging directories.

The first bug produced the following traces:

[133860.229792] ------------[ cut here ]------------
[133860.251062] WARNING: CPU: 2 PID: 26057 at fs/btrfs/locking.c:46 btrfs_set_lock_blocking_rw+0x57/0xbd [btrfs]()
[133860.253576] Modules linked in: btrfs crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc i2c_piix4 psmouse parport
[133860.282566] CPU: 2 PID: 26057 Comm: btrfs Tainted: G        W       4.3.0-rc5-btrfs-next-17+ #1
[133860.284393] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[133860.286827]  0000000000000000 ffff880207697b78 ffffffff812566f4 0000000000000000
[133860.288341]  ffff880207697bb0 ffffffff8104d0a6 ffffffffa052d4c1 ffff880178f60e00
[133860.294219]  ffff880178f60e00 0000000000000000 00000000000000f6 ffff880207697bc0
[133860.295831] Call Trace:
[133860.306518]  [<ffffffff812566f4>] dump_stack+0x4e/0x79
[133860.307473]  [<ffffffff8104d0a6>] warn_slowpath_common+0x9f/0xb8
[133860.308619]  [<ffffffffa052d4c1>] ? btrfs_set_lock_blocking_rw+0x57/0xbd [btrfs]
[133860.310068]  [<ffffffff8104d172>] warn_slowpath_null+0x1a/0x1c
[133860.312552]  [<ffffffffa052d4c1>] btrfs_set_lock_blocking_rw+0x57/0xbd [btrfs]
[133860.314630]  [<ffffffffa04d5787>] btrfs_set_lock_blocking+0xe/0x10 [btrfs]
[133860.323596]  [<ffffffffa04d99cb>] btrfs_realloc_node+0xb3/0x341 [btrfs]
[133860.325233]  [<ffffffffa050e396>] btrfs_defrag_leaves+0x239/0x2fa [btrfs]
[133860.332427]  [<ffffffffa04fc2ce>] btrfs_defrag_root+0x63/0xca [btrfs]
[133860.337259]  [<ffffffffa052a34e>] btrfs_ioctl_defrag+0x78/0x14e [btrfs]
[133860.340147]  [<ffffffffa052b00b>] btrfs_ioctl+0x746/0x24c6 [btrfs]
[133860.344833]  [<ffffffff81087481>] ? arch_local_irq_save+0x9/0xc
[133860.346343]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[133860.353248]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[133860.354242]  [<ffffffff8113adba>] ? __might_fault+0xa5/0xa7
[133860.355232]  [<ffffffff81171139>] ? cp_new_stat+0x15d/0x174
[133860.356237]  [<ffffffff8117c610>] do_vfs_ioctl+0x427/0x4e6
[133860.358587]  [<ffffffff81171175>] ? SYSC_newfstat+0x25/0x2e
[133860.360195]  [<ffffffff8118574d>] ? __fget_light+0x4d/0x71
[133860.361380]  [<ffffffff8117c726>] SyS_ioctl+0x57/0x79
[133860.363578]  [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f
[133860.366217] ---[ end trace 2cadb2f653437e49 ]---
[133860.367399] ------------[ cut here ]------------
[133860.368162] kernel BUG at fs/btrfs/locking.c:307!
[133860.369430] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[133860.370205] Modules linked in: btrfs crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc i2c_piix4 psmouse parport
[133860.370205] CPU: 2 PID: 26057 Comm: btrfs Tainted: G        W       4.3.0-rc5-btrfs-next-17+ #1
[133860.370205] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[133860.370205] task: ffff8800aec6db40 ti: ffff880207694000 task.ti: ffff880207694000
[133860.370205] RIP: 0010:[<ffffffffa052d466>]  [<ffffffffa052d466>] btrfs_assert_tree_locked+0x10/0x14 [btrfs]
[133860.370205] RSP: 0018:ffff880207697bc0  EFLAGS: 00010246
[133860.370205] RAX: 0000000000000000 RBX: ffff880178f60e00 RCX: 0000000000000000
[133860.370205] RDX: ffff88023ec4fb50 RSI: 00000000ffffffff RDI: ffff880178f60e00
[133860.370205] RBP: ffff880207697bc0 R08: 0000000000000001 R09: 0000000000000000
[133860.370205] R10: 0000160000000000 R11: ffffffff81651000 R12: ffff880178f60e00
[133860.370205] R13: 0000000000000000 R14: 00000000000000f6 R15: ffff8801ff409000
[133860.370205] FS:  00007f763efd48c0(0000) GS:ffff88023ec40000(0000) knlGS:0000000000000000
[133860.370205] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[133860.370205] CR2: 0000000002158048 CR3: 000000003fd6c000 CR4: 00000000000006e0
[133860.370205] Stack:
[133860.370205]  ffff880207697bd8 ffffffffa052d4d0 0000000000000000 ffff880207697be8
[133860.370205]  ffffffffa04d5787 ffff880207697c80 ffffffffa04d99cb ffff8801ff409590
[133860.370205]  ffff880207697ca8 000000f507697c80 ffff880183c11bb8 0000000000000000
[133860.370205] Call Trace:
[133860.370205]  [<ffffffffa052d4d0>] btrfs_set_lock_blocking_rw+0x66/0xbd [btrfs]
[133860.370205]  [<ffffffffa04d5787>] btrfs_set_lock_blocking+0xe/0x10 [btrfs]
[133860.370205]  [<ffffffffa04d99cb>] btrfs_realloc_node+0xb3/0x341 [btrfs]
[133860.370205]  [<ffffffffa050e396>] btrfs_defrag_leaves+0x239/0x2fa [btrfs]
[133860.370205]  [<ffffffffa04fc2ce>] btrfs_defrag_root+0x63/0xca [btrfs]
[133860.370205]  [<ffffffffa052a34e>] btrfs_ioctl_defrag+0x78/0x14e [btrfs]
[133860.370205]  [<ffffffffa052b00b>] btrfs_ioctl+0x746/0x24c6 [btrfs]
[133860.370205]  [<ffffffff81087481>] ? arch_local_irq_save+0x9/0xc
[133860.370205]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[133860.370205]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[133860.370205]  [<ffffffff8113adba>] ? __might_fault+0xa5/0xa7
[133860.370205]  [<ffffffff81171139>] ? cp_new_stat+0x15d/0x174
[133860.370205]  [<ffffffff8117c610>] do_vfs_ioctl+0x427/0x4e6
[133860.370205]  [<ffffffff81171175>] ? SYSC_newfstat+0x25/0x2e
[133860.370205]  [<ffffffff8118574d>] ? __fget_light+0x4d/0x71
[133860.370205]  [<ffffffff8117c726>] SyS_ioctl+0x57/0x79
[133860.370205]  [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f

This bug happened because we assumed that by setting keep_locks to 1 in
our search path, our path after a call to btrfs_search_slot() would have
all nodes locked, which is not always true because unlock_up() (called by
btrfs_search_slot()) will unlock a node in a path if the slot of the node
below it doesn't point to the last item or beyond the last item. For
example, when the tree has a heigth of 2 and path->slots[0] has a value
smaller than btrfs_header_nritems(path->nodes[0]) - 1, the node at level 2
will be unlocked (also because lowest_unlock is set to 1 due to the fact
that the value passed as ins_len to btrfs_search_slot is 0).
This resulted in btrfs_find_next_key(), called before btrfs_realloc_node(),
to release out path and call again btrfs_search_slot(), but this time with
the cow parameter set to 0, meaning the resulting path got only read locks.
Therefore when we called btrfs_realloc_node(), with path->nodes[1] having
a read lock, it resulted in the warning and BUG_ON when calling
btrfs_set_lock_blocking() against the node, as that function expects the
node to have a write lock.

The second bug happened often when the first bug didn't happen, and made
us hang and hitting the following warning at fs/btrfs/locking.c:

   251  void btrfs_tree_lock(struct extent_buffer *eb)
   252  {
   253          WARN_ON(eb->lock_owner == current->pid);

This happened because the tree search we made at btrfs_defrag_leaves()
before calling btrfs_find_next_key() locked a leaf and all the other
nodes in the path, so btrfs_find_next_key() had no need to release the
path and make a new search (with path->lowest_level set to 1). This
made btrfs_realloc_node() attempt to write lock the same leaf again,
resulting in a hang/deadlock.

So fix these issues by calling btrfs_find_next_key() after calling
btrfs_realloc_node() and setting the search path's lowest_level to 1
to avoid the hang/deadlock when attempting to write lock the leaves
at btrfs_realloc_node().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-18 02:51:32 +00:00
Omar Sandoval
70f6d82ec7 Btrfs: add free space tree mount option
Now we can finally hook up everything so we can actually use free space
tree. The free space tree is enabled by passing the space_cache=v2 mount
option. On the first mount with the this option set, the free space tree
will be created and the FREE_SPACE_TREE read-only compat bit will be
set. Any time the filesystem is mounted from then on, we must use the
free space tree. The clear_cache option will also clear the free space
tree.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:47 -08:00
Omar Sandoval
1e144fb8f4 Btrfs: wire up the free space tree to the extent tree
The free space tree is updated in tandem with the extent tree. There are
only a handful of places where we need to hook in:

1. Block group creation
2. Block group deletion
3. Delayed refs (extent creation and deletion)
4. Block group caching

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:47 -08:00
Omar Sandoval
7c55ee0c4a Btrfs: add free space tree sanity tests
This tests the operations on the free space tree trying to excercise all
of the main cases for both formats. Between this and xfstests, the free
space tree should have pretty good coverage.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:47 -08:00
Omar Sandoval
a5ed918285 Btrfs: implement the free space B-tree
The free space cache has turned out to be a scalability bottleneck on
large, busy filesystems. When the cache for a lot of block groups needs
to be written out, we can get extremely long commit times; if this
happens in the critical section, things are especially bad because we
block new transactions from happening.

The main problem with the free space cache is that it has to be written
out in its entirety and is managed in an ad hoc fashion. Using a B-tree
to store free space fixes this: updates can be done as needed and we get
all of the benefits of using a B-tree: checksumming, RAID handling,
well-understood behavior.

With the free space tree, we get commit times that are about the same as
the no cache case with load times slower than the free space cache case
but still much faster than the no cache case. Free space is represented
with extents until it becomes more space-efficient to use bitmaps,
giving us similar space overhead to the free space cache.

The operations on the free space tree are: adding and removing free
space, handling the creation and deletion of block groups, and loading
the free space for a block group. We can also create the free space tree
by walking the extent tree and clear the free space tree.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:47 -08:00
Omar Sandoval
208acb8c72 Btrfs: introduce the free space B-tree on-disk format
The on-disk format for the free space tree is straightforward. Each
block group is represented in the free space tree by a free space info
item that stores accounting information: whether the free space for this
block group is stored as bitmaps or extents and how many extents of free
space exist for this block group (regardless of which format is being
used in the tree). Extents are (start, FREE_SPACE_EXTENT, length) keys
with no corresponding item, and bitmaps instead have the
FREE_SPACE_BITMAP type and have a bitmap item attached, which is just an
array of bytes.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Omar Sandoval
73fa48b674 Btrfs: refactor caching_thread()
We're also going to load the free space tree from caching_thread(), so
we should refactor some of the common code.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Omar Sandoval
1abfbcdf56 Btrfs: add helpers for read-only compat bits
We're finally going to add one of these for the free space tree, so
let's add the same nice helpers that we have for the incompat bits.
While we're add it, also add helpers to clear the bits.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Omar Sandoval
0f3312295d Btrfs: add extent buffer bitmap sanity tests
Sanity test the extent buffer bitmap operations (test, set, and clear)
against the equivalent standard kernel operations.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Omar Sandoval
3e1e8bb770 Btrfs: add extent buffer bitmap operations
These are going to be used for the free space tree bitmap items.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-17 12:16:46 -08:00
Filipe Manana
f28a492878 Btrfs: fix leaking of ordered extents after direct IO write error
When doing a direct IO write, __blockdev_direct_IO() can call the
btrfs_get_blocks_direct() callback one or more times before it calls the
btrfs_submit_direct() callback. However it can fail after calling the
first callback and before calling the second callback, which is a problem
because the first one creates ordered extents and the second one is the
one that submits bios that cover the ordered extents created by the first
one. That means the ordered extents will never complete nor have any of
the flags BTRFS_ORDERED_IO_DONE / BTRFS_ORDERED_IOERR set, resulting in
subsequent operations (such as other direct IO writes, buffered writes or
hole punching) that lock the same IO range and lookup for ordered extents
in the range to hang forever waiting for those ordered extents because
they can not complete ever, since no bio was submitted.

Fix this by tracking a range of created ordered extents that don't have
yet corresponding bios submitted and completing the ordered extents in
the range if __blockdev_direct_IO() fails with an error.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-17 10:59:51 +00:00
Filipe Manana
b850ae1427 Btrfs: fix deadlock between direct IO write and defrag/readpages
If readpages() (triggered by defrag or buffered reads) is called while a
direct IO write is in progress, we have a small time window where we can
deadlock, resulting in traces like the following being generated:

[84723.212993] INFO: task fio:2849 blocked for more than 120 seconds.
[84723.214310]       Tainted: G        W       4.3.0-rc5-btrfs-next-17+ #1
[84723.215640] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[84723.217313] fio        D ffff88023ec75218     0  2849   2835 0x00000000
[84723.218778]  ffff880122dfb6e8 0000000000000092 0000000000000000 ffff88023ec75200
[84723.220458]  ffff88000e05d2c0 ffff880122dfc000 ffff88023ec75200 7fffffffffffffff
[84723.230597]  0000000000000002 ffffffff8147891a ffff880122dfb700 ffffffff8147856a
[84723.232085] Call Trace:
[84723.232625]  [<ffffffff8147891a>] ? bit_wait+0x3c/0x3c
[84723.233529]  [<ffffffff8147856a>] schedule+0x7d/0x95
[84723.234398]  [<ffffffff8147baa3>] schedule_timeout+0x43/0x10b
[84723.235384]  [<ffffffff810f82eb>] ? time_hardirqs_on+0x15/0x28
[84723.236426]  [<ffffffff8108a23d>] ? trace_hardirqs_on+0xd/0xf
[84723.237502]  [<ffffffff810af8a3>] ? read_seqcount_begin.constprop.20+0x57/0x6d
[84723.238807]  [<ffffffff8108a09b>] ? trace_hardirqs_on_caller+0x16/0x1ab
[84723.242012]  [<ffffffff8108a23d>] ? trace_hardirqs_on+0xd/0xf
[84723.243064]  [<ffffffff810af2ad>] ? timekeeping_get_ns+0xe/0x33
[84723.244116]  [<ffffffff810afa2e>] ? ktime_get+0x41/0x52
[84723.245029]  [<ffffffff81477cff>] io_schedule_timeout+0xb7/0x12b
[84723.245942]  [<ffffffff81477cff>] ? io_schedule_timeout+0xb7/0x12b
[84723.246596]  [<ffffffff81478953>] bit_wait_io+0x39/0x45
[84723.247503]  [<ffffffff81478b93>] __wait_on_bit_lock+0x49/0x8d
[84723.248540]  [<ffffffff8111684f>] __lock_page+0x66/0x68
[84723.249558]  [<ffffffff81081c9b>] ? autoremove_wake_function+0x3a/0x3a
[84723.250844]  [<ffffffff81124a04>] lock_page+0x2c/0x2f
[84723.251871]  [<ffffffff81124afc>] invalidate_inode_pages2_range+0xf5/0x2aa
[84723.253274]  [<ffffffff81117c34>] ? filemap_fdatawait_range+0x12d/0x146
[84723.254757]  [<ffffffff81118191>] ? filemap_fdatawrite_range+0x13/0x15
[84723.256378]  [<ffffffffa05139a2>] btrfs_get_blocks_direct+0x1b0/0x664 [btrfs]
[84723.258556]  [<ffffffff8119e3f9>] ? submit_page_section+0x7b/0x111
[84723.260064]  [<ffffffff8119eb90>] do_blockdev_direct_IO+0x658/0xbdb
[84723.261479]  [<ffffffffa05137f2>] ? btrfs_page_exists_in_range+0x1a9/0x1a9 [btrfs]
[84723.262961]  [<ffffffffa050a8a6>] ? btrfs_writepage_start_hook+0xce/0xce [btrfs]
[84723.264449]  [<ffffffff8119f144>] __blockdev_direct_IO+0x31/0x33
[84723.265614]  [<ffffffff8119f144>] ? __blockdev_direct_IO+0x31/0x33
[84723.266769]  [<ffffffffa050a8a6>] ? btrfs_writepage_start_hook+0xce/0xce [btrfs]
[84723.268264]  [<ffffffffa050935d>] btrfs_direct_IO+0x1b9/0x259 [btrfs]
[84723.270954]  [<ffffffffa050a8a6>] ? btrfs_writepage_start_hook+0xce/0xce [btrfs]
[84723.272465]  [<ffffffff8111878c>] generic_file_direct_write+0xb3/0x128
[84723.273734]  [<ffffffffa051955c>] btrfs_file_write_iter+0x228/0x404 [btrfs]
[84723.275101]  [<ffffffff8116ca6f>] __vfs_write+0x7c/0xa5
[84723.276200]  [<ffffffff8116cfab>] vfs_write+0xa0/0xe4
[84723.277298]  [<ffffffff8116d79d>] SyS_write+0x50/0x7e
[84723.278327]  [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f
[84723.279595] INFO: lockdep is turned off.
[84723.379035] INFO: task btrfs:2923 blocked for more than 120 seconds.
[84723.380323]       Tainted: G        W       4.3.0-rc5-btrfs-next-17+ #1
[84723.381608] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[84723.383003] btrfs           D ffff88023ed75218     0  2923   2859 0x00000000
[84723.384277]  ffff88001311f860 0000000000000082 ffff88001311f840 ffff88023ed75200
[84723.385748]  ffff88012c6751c0 ffff880013120000 ffff88012042fe68 ffff88012042fe30
[84723.387152]  ffff880221571c88 0000000000000001 ffff88001311f878 ffffffff8147856a
[84723.388620] Call Trace:
[84723.389105]  [<ffffffff8147856a>] schedule+0x7d/0x95
[84723.391882]  [<ffffffffa051da32>] btrfs_start_ordered_extent+0x161/0x1fa [btrfs]
[84723.393718]  [<ffffffff81081c61>] ? signal_pending_state+0x31/0x31
[84723.395659]  [<ffffffffa0522c5b>] __do_contiguous_readpages.constprop.21+0x81/0xdc [btrfs]
[84723.397383]  [<ffffffffa050ac96>] ? btrfs_submit_direct+0x3f0/0x3f0 [btrfs]
[84723.398852]  [<ffffffffa0522da3>] __extent_readpages.constprop.20+0xed/0x100 [btrfs]
[84723.400561]  [<ffffffff81123f6c>] ? __lru_cache_add+0x5d/0x72
[84723.401787]  [<ffffffffa0523896>] extent_readpages+0x111/0x1a7 [btrfs]
[84723.403121]  [<ffffffffa050ac96>] ? btrfs_submit_direct+0x3f0/0x3f0 [btrfs]
[84723.404583]  [<ffffffffa05088fa>] btrfs_readpages+0x1f/0x21 [btrfs]
[84723.406007]  [<ffffffff811226df>] __do_page_cache_readahead+0x168/0x1f4
[84723.407502]  [<ffffffff81122988>] ondemand_readahead+0x21d/0x22e
[84723.408937]  [<ffffffff81122988>] ? ondemand_readahead+0x21d/0x22e
[84723.410487]  [<ffffffff81122af1>] page_cache_sync_readahead+0x3d/0x3f
[84723.411710]  [<ffffffffa0535388>] btrfs_defrag_file+0x419/0xaaf [btrfs]
[84723.413007]  [<ffffffffa0531db0>] ? kzalloc+0xf/0x11 [btrfs]
[84723.414085]  [<ffffffffa0535b43>] btrfs_ioctl_defrag+0x125/0x14e [btrfs]
[84723.415307]  [<ffffffffa0536753>] btrfs_ioctl+0x746/0x24c6 [btrfs]
[84723.416532]  [<ffffffff81087481>] ? arch_local_irq_save+0x9/0xc
[84723.417731]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[84723.418699]  [<ffffffff8113ad61>] ? __might_fault+0x4c/0xa7
[84723.421532]  [<ffffffff8113adba>] ? __might_fault+0xa5/0xa7
[84723.422629]  [<ffffffff81171139>] ? cp_new_stat+0x15d/0x174
[84723.423712]  [<ffffffff8117c610>] do_vfs_ioctl+0x427/0x4e6
[84723.424801]  [<ffffffff81171175>] ? SYSC_newfstat+0x25/0x2e
[84723.425968]  [<ffffffff8118574d>] ? __fget_light+0x4d/0x71
[84723.427063]  [<ffffffff8117c726>] SyS_ioctl+0x57/0x79
[84723.428138]  [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f

Consider the following logical and physical file layout:

logical:    ... [ prealloc extent A ] [ prealloc extent B ] [ extent C ] ...
                4K                    8K                    16K

physical:   ... 12853248              12857344              1103101952   ...
                                      (= 12853248 + 4K)

Extents A and B are physically adjacent. The following diagram shows a
sequence of events that lead to the deadlock when we attempt to do a
direct IO write against the file range [4K, 16K[ and a defrag is triggered
simultaneously.

           CPU 1                                               CPU 2

 btrfs_direct_IO()

   btrfs_get_blocks_direct()
     creates ordered extent A, covering
     the 4k prealloc extent A (range [4K, 8K[)

                                                    btrfs_defrag_file()
                                                      page_cache_sync_readahead([0K, 1M[)
                                                        btrfs_readpages()
                                                          extent_readpages()

                                                            locks all pages in the file
                                                            range [0K, 128K[ through calls
                                                            to add_to_page_cache_lru()

                                                            __do_contiguous_readpages()

                                                               finds ordered extent A

                                                               waits for it to complete

   btrfs_get_blocks_direct() called again

     lock_extent_direct(range [8K, 16K[)

       finds a page in range [8K, 16K[ through
       btrfs_page_exists_in_range()

       invalidate_inode_pages2_range([8K, 16K[)

         --> tries to lock pages that are already
             locked by the task at CPU 2

         --> our task, running __blockdev_direct_IO(),
             hangs waiting to lock the pages and the
             submit bio callback, btrfs_submit_direct(),
             ends up never being called, resulting in the
             ordered extent A never completing (because a
             corresponding bio is never submitted) and
             CPU 2 will wait for it forever while holding
             the pages locked
              ---> deadlock!

Fix this by removing the page invalidation approach when attempting to
lock the range for IO from the callback btrfs_get_blocks_direct() and
falling back buffered IO. This was a rare case anyway and well behaved
applications do not mix concurrent direct IO writes with buffered reads
anyway, being a concurrent defrag the only normal case that could lead
to the deadlock.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-17 10:59:50 +00:00
Filipe Manana
14543774bd Btrfs: fix error path when failing to submit bio for direct IO write
Commit 61de718fce ("Btrfs: fix memory corruption on failure to submit
bio for direct IO") fixed problems with the error handling code after we
fail to submit a bio for direct IO. However there were 2 problems that it
did not address when the failure is due to memory allocation failures for
direct IO writes:

1) We considered that there could be only one ordered extent for the whole
   IO range, which is not always true, as we can have multiple;

2) It did not set the bit BTRFS_ORDERED_IO_DONE in the ordered extent,
   which can make other tasks running btrfs_wait_logged_extents() hang
   forever, since they wait for that bit to be set. The general assumption
   is that regardless of an error, the BTRFS_ORDERED_IO_DONE is always set
   and it precedes setting the bit BTRFS_ORDERED_COMPLETE.

Fix these issues by moving part of the btrfs_endio_direct_write() handler
into a new helper function and having that new helper function called when
we fail to allocate memory to submit the bio (and its private object) for
a direct IO write.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2015-12-17 10:59:49 +00:00
Filipe Manana
7785a663c4 Btrfs: fix memory leaks after transaction is aborted
When a transaction is aborted, or its commit fails before writing the new
superblock and calling btrfs_finish_extent_commit(), we leak reference
counts on the block groups attached to the transaction's delete_bgs list,
because btrfs_finish_extent_commit() is never called for those two cases.
Fix this by dropping their references at btrfs_put_transaction(), which
is called when transactions are aborted (by making the transaction kthread
commit the transaction) or if their commits fail.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-17 10:59:48 +00:00
Filipe Manana
50460e3718 Btrfs: fix race when finishing dev replace leading to transaction abort
During the final phase of a device replace operation, I ran into a
transaction abort that resulted in the following trace:

[23919.655368] WARNING: CPU: 10 PID: 30175 at fs/btrfs/extent-tree.c:9843 btrfs_create_pending_block_groups+0x15e/0x1ab [btrfs]()
[23919.664742] BTRFS: Transaction aborted (error -2)
[23919.665749] Modules linked in: btrfs crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc i2c_piix4 parport psmouse acpi_cpufreq processor i2c_core evdev microcode pcspkr button serio_raw ext4 crc16 jbd2 mbcache sd_mod sg sr_mod cdrom virtio_scsi ata_generic ata_piix virtio_pci floppy virtio_ring libata e1000 virtio scsi_mod [last unloaded: btrfs]
[23919.679442] CPU: 10 PID: 30175 Comm: fsstress Not tainted 4.3.0-rc5-btrfs-next-17+ #1
[23919.682392] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
[23919.689151]  0000000000000000 ffff8804020cbb50 ffffffff812566f4 ffff8804020cbb98
[23919.692604]  ffff8804020cbb88 ffffffff8104d0a6 ffffffffa03eea69 ffff88041b678a48
[23919.694230]  ffff88042ac38000 ffff88041b678930 00000000fffffffe ffff8804020cbbf0
[23919.696716] Call Trace:
[23919.698669]  [<ffffffff812566f4>] dump_stack+0x4e/0x79
[23919.700597]  [<ffffffff8104d0a6>] warn_slowpath_common+0x9f/0xb8
[23919.701958]  [<ffffffffa03eea69>] ? btrfs_create_pending_block_groups+0x15e/0x1ab [btrfs]
[23919.703612]  [<ffffffff8104d107>] warn_slowpath_fmt+0x48/0x50
[23919.705047]  [<ffffffffa03eea69>] btrfs_create_pending_block_groups+0x15e/0x1ab [btrfs]
[23919.706967]  [<ffffffffa0402097>] __btrfs_end_transaction+0x84/0x2dd [btrfs]
[23919.708611]  [<ffffffffa0402300>] btrfs_end_transaction+0x10/0x12 [btrfs]
[23919.710099]  [<ffffffffa03ef0b8>] btrfs_alloc_data_chunk_ondemand+0x121/0x28b [btrfs]
[23919.711970]  [<ffffffffa0413025>] btrfs_fallocate+0x7d3/0xc6d [btrfs]
[23919.713602]  [<ffffffff8108b78f>] ? lock_acquire+0x10d/0x194
[23919.714756]  [<ffffffff81086dbc>] ? percpu_down_read+0x51/0x78
[23919.716155]  [<ffffffff8116ef1d>] ? __sb_start_write+0x5f/0xb0
[23919.718918]  [<ffffffff8116ef1d>] ? __sb_start_write+0x5f/0xb0
[23919.724170]  [<ffffffff8116b579>] vfs_fallocate+0x170/0x1ff
[23919.725482]  [<ffffffff8117c1d7>] ioctl_preallocate+0x89/0x9b
[23919.726790]  [<ffffffff8117c5ef>] do_vfs_ioctl+0x406/0x4e6
[23919.728428]  [<ffffffff81171175>] ? SYSC_newfstat+0x25/0x2e
[23919.729642]  [<ffffffff8118574d>] ? __fget_light+0x4d/0x71
[23919.730782]  [<ffffffff8117c726>] SyS_ioctl+0x57/0x79
[23919.731847]  [<ffffffff8147cd97>] entry_SYSCALL_64_fastpath+0x12/0x6f
[23919.733330] ---[ end trace 166ef301a335832a ]---

This is due to a race between device replace and chunk allocation, which
the following diagram illustrates:

         CPU 1                                    CPU 2

 btrfs_dev_replace_finishing()

   at this point
    dev_replace->tgtdev->devid ==
    BTRFS_DEV_REPLACE_DEVID (0ULL)

   ...

   btrfs_start_transaction()
   btrfs_commit_transaction()

                                               btrfs_fallocate()
                                                 btrfs_alloc_data_chunk_ondemand()
                                                   btrfs_join_transaction()
                                                     --> starts a new transaction
                                                   do_chunk_alloc()
                                                     lock fs_info->chunk_mutex
                                                       btrfs_alloc_chunk()
                                                         --> creates extent map for
                                                             the new chunk with
                                                             em->bdev->map->stripes[i]->dev->devid
                                                             == X (X > 0)
                                                         --> extent map is added to
                                                             fs_info->mapping_tree
                                                         --> initial phase of bg A
                                                             allocation completes
                                                     unlock fs_info->chunk_mutex

   lock fs_info->chunk_mutex

   btrfs_dev_replace_update_device_in_mapping_tree()
     --> iterates fs_info->mapping_tree and
         replaces the device in every extent
         map's map->stripes[] with
         dev_replace->tgtdev, which still has
         an id of 0ULL (BTRFS_DEV_REPLACE_DEVID)

                                                   btrfs_end_transaction()
                                                     btrfs_create_pending_block_groups()
                                                       --> starts final phase of
                                                           bg A creation (update device,
                                                           extent, and chunk trees, etc)
                                                       btrfs_finish_chunk_alloc()

                                                         btrfs_update_device()
                                                           --> attempts to update a device
                                                               item with ID == 0ULL
                                                               (BTRFS_DEV_REPLACE_DEVID)
                                                               which is the current ID of
                                                               bg A's
                                                               em->bdev->map->stripes[i]->dev->devid
                                                           --> doesn't find such item
                                                               returns -ENOENT
                                                           --> the device id should have been X
                                                               and not 0ULL

                                                       got -ENOENT from
                                                       btrfs_finish_chunk_alloc()
                                                       and aborts current transaction

   finishes setting up the target device,
   namely it sets tgtdev->devid to the value
   of srcdev->devid, which is X (and X > 0)

   frees the srcdev

   unlock fs_info->chunk_mutex

So fix this by taking the device list mutex when processing the chunk's
extent map stripes to update the device items. This avoids getting the
wrong device id and use-after-free problems if the task finishing a
chunk allocation grabs the replaced device, which is freed while the
dev replace task is holding the device list mutex.

This happened while running fstest btrfs/071.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2015-12-17 10:59:46 +00:00
Chris Mason
1d3a5a82fe Merge branch 'for-chris-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.4 2015-12-15 09:09:59 -08:00
Chris Mason
bb1591b4ea Btrfs: check prepare_uptodate_page() error code earlier
prepare_pages() may end up calling prepare_uptodate_page() twice if our
write only spans a single page.  But if the first call returns an error,
our page will be unlocked and its not safe to call it again.

This bug goes all the way back to 2011, and it's not something commonly
hit.

While we're here, add a more explicit check for the page being truncated
away.  The bare lock_page() alone is protected only by good thoughts and
i_mutex, which we're sure to regret eventually.

Reported-by: Dave Jones <dsj@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-15 09:09:38 -08:00
Chris Mason
1b9b922a3a Btrfs: check for empty bitmap list in setup_cluster_bitmaps
Dave Jones found a warning from kasan in setup_cluster_bitmaps()

==================================================================
BUG: KASAN: stack-out-of-bounds in setup_cluster_bitmap+0xc4/0x5a0 at
addr ffff88039bef6828
Read of size 8 by task nfsd/1009
page:ffffea000e6fbd80 count:0 mapcount:0 mapping:          (null)
index:0x0
flags: 0x8000000000000000()
page dumped because: kasan: bad access detected
CPU: 1 PID: 1009 Comm: nfsd Tainted: G        W
4.4.0-rc3-backup-debug+ #1
 ffff880065647b50 000000006bb712c2 ffff88039bef6640 ffffffffa680a43e
 0000004559c00000 ffff88039bef66c8 ffffffffa62638d1 ffffffffa61121c0
 ffff8803a5769de8 0000000000000296 ffff8803a5769df0 0000000000046280
Call Trace:
 [<ffffffffa680a43e>] dump_stack+0x4b/0x6d
 [<ffffffffa62638d1>] kasan_report_error+0x501/0x520
 [<ffffffffa61121c0>] ? debug_show_all_locks+0x1e0/0x1e0
 [<ffffffffa6263948>] kasan_report+0x58/0x60
 [<ffffffffa6814b00>] ? rb_last+0x10/0x40
 [<ffffffffa66f8af4>] ? setup_cluster_bitmap+0xc4/0x5a0
 [<ffffffffa6262ead>] __asan_load8+0x5d/0x70
 [<ffffffffa66f8af4>] setup_cluster_bitmap+0xc4/0x5a0
 [<ffffffffa66f675a>] ? setup_cluster_no_bitmap+0x6a/0x400
 [<ffffffffa66fcd16>] btrfs_find_space_cluster+0x4b6/0x640
 [<ffffffffa66fc860>] ? btrfs_alloc_from_cluster+0x4e0/0x4e0
 [<ffffffffa66fc36e>] ? btrfs_return_cluster_to_free_space+0x9e/0xb0
 [<ffffffffa702dc37>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa666a1a1>] find_free_extent+0xba1/0x1520

Andrey noticed this was because we were doing list_first_entry on a list
that might be empty.  Rework the tests a bit so we don't do that.

Signed-off-by: Chris Mason <clm@fb.com>
Reprorted-by: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Reported-by:  Dave Jones <dsj@fb.com>
2015-12-15 09:09:33 -08:00
Peter Zijlstra
dfd01f0260 sched/wait: Fix the signal handling fix
Jan Stancek reported that I wrecked things for him by fixing things for
Vladimir :/

His report was due to an UNINTERRUPTIBLE wait getting -EINTR, which
should not be possible, however my previous patch made this possible by
unconditionally checking signal_pending().

We cannot use current->state as was done previously, because the
instruction after the store to that variable it can be changed.  We must
instead pass the initial state along and use that.

Fixes: 68985633bc ("sched/wait: Fix signal handling in bit wait helpers")
Reported-by: Jan Stancek <jstancek@redhat.com>
Reported-by: Chris Mason <clm@fb.com>
Tested-by: Jan Stancek <jstancek@redhat.com>
Tested-by: Vladimir Murzin <vladimir.murzin@arm.com>
Tested-by: Chris Mason <clm@fb.com>
Reviewed-by: Paul Turner <pjt@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: tglx@linutronix.de
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: hpa@zytor.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-13 14:30:59 -08:00
Linus Torvalds
fc89182834 NFS client bugfix for Linux 4.4
Bugfixes:
 - SUNRPC: Fix a NFSv4.1 callback channel regression
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJWba3xAAoJEGcL54qWCgDyMLQQAJKU4s513LiYJ9UDil5Q+sfP
 B4flTt/uH1v3MLX31J9Z987jFNsqd9sGaw4E+03xrZNZRY5gToG7iko2im2S6YlW
 E6+yoK45JGZGbJVIMx1pUdzEuBlwtpn+kivrPEte1veJfw5LFwL8NbLjd4Kz1JXi
 h38Wv6OEvrHJJCWtkHjSVSj1ediqgULq11pHYF2kgOctLPcwMlO7XqwX6EDs2G0T
 lrJn6lK0J+0ULOTaf6OH1jdvCj30AfqpvbrT+BTxUnfzLNFWLNn8f0j8b7QRe/lM
 enmAq/1seK2S9v//D5qDcuNcuH41lhyGNfQsduJE8w2XOlYgbDWT0LIPNQr6XWLW
 DkHhuNA4N7TrCRKy07DEQTwR1+oaONX1z4N/cK73K8z+LkF4V5aQVbpYC8NU88+U
 /78Zjtht8gcYwKeEC2fTll1nufVbkbiWINQeMIXYauheOlB+hmyCm6KZ9EdX8AZS
 ItWJcf+n9Mp5Uu5tjeVquifymr5smZzgM9pRXnMljrhr/bqUwecy23lFmgiz4L4B
 pTUggOXgOu2Zs6K699wvaeZVpUv0mt29JDjB4bDIUBaMLDFy9l4L83HKfX3dUtHQ
 DpchaLjrQN57KpwWMmILxjC9u4yPv3+KRRjNZJiBP6+NEfeQO2iNl1ZoH2XRKHOR
 c4ZPFBuKSFdO1zwrdZHc
 =55Qy
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.4-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfix from Trond Myklebust:
 "SUNRPC: Fix a NFSv4.1 callback channel regression"

* tag 'nfs-for-4.4-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Fix callback channel
2015-12-13 12:46:04 -08:00
Linus Torvalds
800f1ac479 Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
 "17 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  MIPS: fix DMA contiguous allocation
  sh64: fix __NR_fgetxattr
  ocfs2: fix SGID not inherited issue
  mm/oom_kill.c: avoid attempting to kill init sharing same memory
  drivers/base/memory.c: prohibit offlining of memory blocks with missing sections
  tmpfs: fix shmem_evict_inode() warnings on i_blocks
  mm/hugetlb.c: fix resv map memory leak for placeholder entries
  mm: hugetlb: call huge_pte_alloc() only if ptep is null
  kernel: remove stop_machine() Kconfig dependency
  mm: kmemleak: mark kmemleak_init prototype as __init
  mm: fix kerneldoc on mem_cgroup_replace_page
  osd fs: __r4w_get_page rely on PageUptodate for uptodate
  MAINTAINERS: make Vladimir co-maintainer of the memory controller
  mm, vmstat: allow WQ concurrency to discover memory reclaim doesn't make any progress
  mm: fix swapped Movable and Reclaimable in /proc/pagetypeinfo
  memcg: fix memory.high target
  mm: hugetlb: fix hugepage memory leak caused by wrong reserve count
2015-12-12 10:44:49 -08:00
Linus Torvalds
7807563183 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block layer fixes from Jens Axboe:
 "A set of fixes for the current series.  This contains:

   - A bunch of fixes for lightnvm, should be the last round for this
     series.  From Matias and Wenwei.

   - A writeback detach inode fix from Ilya, also marked for stable.

   - A block (though it says SCSI) fix for an OOPS in SCSI runtime power
     management.

   - Module init error path fixes for null_blk from Minfei"

* 'for-linus' of git://git.kernel.dk/linux-block:
  null_blk: Fix error path in module initialization
  lightnvm: do not compile in debugging by default
  lightnvm: prevent gennvm module unload on use
  lightnvm: fix media mgr registration
  lightnvm: replace req queue with nvmdev for lld
  lightnvm: comments on constants
  lightnvm: check mm before use
  lightnvm: refactor spin_unlock in gennvm_get_blk
  lightnvm: put blks when luns configure failed
  lightnvm: use flags in rrpc_get_blk
  block: detach bdev inode from its wb in __blkdev_put()
  SCSI: Fix NULL pointer dereference in runtime PM
2015-12-12 10:24:00 -08:00
Junxiao Bi
854ee2e944 ocfs2: fix SGID not inherited issue
Commit 8f1eb48758 ("ocfs2: fix umask ignored issue") introduced an
issue, SGID of sub dir was not inherited from its parents dir.  It is
because SGID is set into "inode->i_mode" in ocfs2_get_init_inode(), but
is overwritten by "mode" which don't have SGID set later.

Fixes: 8f1eb48758 ("ocfs2: fix umask ignored issue")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Acked-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-12 10:15:34 -08:00
Hugh Dickins
3066a9670b osd fs: __r4w_get_page rely on PageUptodate for uptodate
Commit 42cb14b110 ("mm: migrate dirty page without
clear_page_dirty_for_io etc") simplified the migration of a PageDirty
pagecache page: one stat needs moving from zone to zone and that's about
all.

It's convenient and safest for it to shift the PageDirty bit from old
page to new, just before updating the zone stats: before copying data
and marking the new PageUptodate.  This is all done while both pages are
isolated and locked, just as before; and just as before, there's a
moment when the new page is visible in the radix_tree, but not yet
PageUptodate.  What's new is that it may now be briefly visible as
PageDirty before it is PageUptodate.

When I scoured the tree to see if this could cause a problem anywhere,
the only places I found were in two similar functions __r4w_get_page():
which look up a page with find_get_page() (not using page lock), then
claim it's uptodate if it's PageDirty or PageWriteback or PageUptodate.

I'm not sure whether that was right before, but now it might be wrong
(on rare occasions): only claim the page is uptodate if PageUptodate.
Or perhaps the page in question could never be migratable anyway?

Signed-off-by: Hugh Dickins <hughd@google.com>
Tested-by: Boaz Harrosh <ooo@electrozaur.com>
Cc: Benny Halevy <bhalevy@panasas.com>
Cc: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: Christoph Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-12-12 10:15:34 -08:00
Linus Torvalds
732c4a9e14 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse fixes from Miklos Szeredi:
 "Two bugfixes, both bound for -stable"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: break infinite loop in fuse_fill_write_pages()
  cuse: fix memory leak
2015-12-11 10:56:41 -08:00
Holger Hoffstätte
94356889c4 btrfs: fix misleading warning when space cache failed to load
When an inconsistent space cache is detected during loading we log a
warning that users frequently mistake as instruction to invalidate the
cache manually, even though this is not required. Fix the message to
indicate that the cache will be rebuilt automatically.

Signed-off-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Acked-by: Filipe Manana <fdmanana@suse.com>
2015-12-10 11:38:08 +00:00
Filipe Manana
8a7d656f3d Btrfs: fix transaction handle leak in balance
If we fail to allocate a new data chunk, we were jumping to the error path
without release the transaction handle we got before. Fix this by always
releasing it before doing the jump.

Fixes: 2c9fe83552 ("btrfs: Fix lost-data-profile caused by balance bg")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-10 11:23:24 +00:00
Filipe Manana
348a0013d5 Btrfs: fix unprotected list move from unused_bgs to deleted_bgs list
As of my previous change titled "Btrfs: fix scrub preventing unused block
groups from being deleted", the following warning at
extent-tree.c:btrfs_delete_unused_bgs() can be hit when we mount the a
filesysten with "-o discard":

 10263  void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
 10264  {
 (...)
 10405                  if (trimming) {
 10406                          WARN_ON(!list_empty(&block_group->bg_list));
 10407                          spin_lock(&trans->transaction->deleted_bgs_lock);
 10408                          list_move(&block_group->bg_list,
 10409                                    &trans->transaction->deleted_bgs);
 10410                          spin_unlock(&trans->transaction->deleted_bgs_lock);
 10411                          btrfs_get_block_group(block_group);
 10412                  }
 (...)

This happens because scrub can now add back the block group to the list of
unused block groups (fs_info->unused_bgs). This is dangerous because we
are moving the block group from the unused block groups list to the list
of deleted block groups without holding the lock that protects the source
list (fs_info->unused_bgs_lock).

The following diagram illustrates how this happens:

            CPU 1                                     CPU 2

 cleaner_kthread()
   btrfs_delete_unused_bgs()

     sees bg X in list
      fs_info->unused_bgs

     deletes bg X from list
      fs_info->unused_bgs

                                            scrub_enumerate_chunks()

                                              searches device tree using
                                              its commit root

                                              finds device extent for
                                              block group X

                                              gets block group X from the tree
                                              fs_info->block_group_cache_tree
                                              (via btrfs_lookup_block_group())

                                              sets bg X to RO (again)

                                              scrub_chunk(bg X)

                                              sets bg X back to RW mode

                                              adds bg X to the list
                                              fs_info->unused_bgs again,
                                              since it's still unused and
                                              currently not in that list

     sets bg X to RO mode

     btrfs_remove_chunk(bg X)

     --> discard is enabled and bg X
         is in the fs_info->unused_bgs
         list again so the warning is
         triggered
     --> we move it from that list into
         the transaction's delete_bgs
         list, but we can have another
         task currently manipulating
         the first list (fs_info->unused_bgs)

Fix this by using the same lock (fs_info->unused_bgs_lock) to protect both
the list of unused block groups and the list of deleted block groups. This
makes it safe and there's not much worry for more lock contention, as this
lock is seldom used and only the cleaner kthread adds elements to the list
of deleted block groups. The warning goes away too, as this was previously
an impossible case (and would have been better a BUG_ON/ASSERT) but it's
not impossible anymore.
Reproduced with fstest btrfs/073 (using MOUNT_OPTIONS="-o discard").

Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-12-10 11:22:38 +00:00
Linus Torvalds
626d114f46 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "A couple of fixes, both -stable fodder (9p one all way back to 2.6.32,
  dio - to all branches where "Fix negative return from dio read beyond
  eof" will end up it; it's a fixup to commit marked for -stable)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix the regression from "direct-io: Fix negative return from dio read beyond eof"
  9p: ->evict_inode() should kick out ->i_data, not ->i_mapping
2015-12-09 09:34:26 -08:00
Al Viro
2d4594acbf fix the regression from "direct-io: Fix negative return from dio read beyond eof"
Sure, it's better to bail out of past-the-eof read and return 0 than return
a bogus negative value on such.  Only we'd better make sure we are bailing out
with 0 and not -ENOMEM...

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08 15:02:42 -05:00
Al Viro
4ad7862844 9p: ->evict_inode() should kick out ->i_data, not ->i_mapping
For block devices the pagecache is associated with the inode
on bdevfs, not with the aliasing ones on the mountable filesystems.
The latter have its own ->i_data empty and ->i_mapping pointing
to the (unique per major/minor) bdevfs inode.  That guarantees
cache coherence between all block device inodes with the same
device number.

Eviction of an alias inode has no business trying to evict the
pages belonging to bdevfs one; moreover, ->i_mapping is only
safe to access when the thing is opened.  At the time of
->evict_inode() the victim is definitely *not* opened.  We are
about to kill the address space embedded into struct inode
(inode->i_data) and that's what we need to empty of any pages.

9p instance tries to empty inode->i_mapping instead, which is
both unsafe and bogus - if we have several device nodes with
the same device number in different places, closing one of them
should not try to empty the (shared) page cache.

Fortunately, other instances in the tree are OK; they are
evicting from &inode->i_data instead, as 9p one should.

Cc: stable@vger.kernel.org # v2.6.32+, ones prior to 2.6.36 need only half of that
Reported-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Tested-by: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08 14:51:16 -05:00
Trond Myklebust
756b9b37cf SUNRPC: Fix callback channel
The NFSv4.1 callback channel is currently broken because the receive
message will keep shrinking because the backchannel receive buffer size
never gets reset.
The easiest solution to this problem is instead of changing the receive
buffer, to rather adjust the copied request.

Fixes: 38b7631fbe ("nfs4: limit callback decoding to received bytes")
Cc: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-12-07 13:04:59 -08:00
Linus Torvalds
f41683a204 Ext4 bug fixes for v4.4, including fixes for post-2038 time encodings,
some endian conversion problems with ext4 encryption, potential memory
 leaks after truncate in data=journal mode, and an ocfs2 regression
 caused by a jbd2 performance improvement.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJWZP5/AAoJEPL5WVaVDYGjLUwH+wZUMghNAiR+AUEDW5MwbRMd
 XGvPFr1ohs9ep6vrayRLAVU+BDbcSvL7GRddFpUabTfDqH6tyk43IqOFaE2UMefj
 +k61vUnEaD7hTOGtgnfkntAcrE8hngTA1UkEGRTRQjRSqKgt1ku2LB/GfGbgv4Yq
 1grwLbq/MRZ6gSZIv8TwuLC7BOAt6mLtxtJB8ozRuhVJVo1gzy1IvXkqn2mgf/h4
 nIq6i720NxZS9HqncA/o1rxfWb2bwEpLj5MYqdgscwHBGql0riHM0HOebAbgvVqV
 FgLM81p4qVry8N4ACNLIJsqjWu3eMcNUZFW3vaObGTg2tODTj8WSEClb56Z6fpE=
 =iOzG
 -----END PGP SIGNATURE-----

Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Ext4 bug fixes for v4.4, including fixes for post-2038 time encodings,
  some endian conversion problems with ext4 encryption, potential memory
  leaks after truncate in data=journal mode, and an ocfs2 regression
  caused by a jbd2 performance improvement"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  jbd2: fix null committed data return in undo_access
  ext4: add "static" to ext4_seq_##name##_fops struct
  ext4: fix an endianness bug in ext4_encrypted_follow_link()
  ext4: fix an endianness bug in ext4_encrypted_zeroout()
  jbd2: Fix unreclaimed pages after truncate in data=journal mode
  ext4: Fix handling of extended tv_sec
2015-12-07 10:25:00 -08:00
David Sterba
35de6db28f btrfs: make set_range_writeback return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
f631157276 btrfs: make extent_range_redirty_for_io return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
bd1fa4f0b0 btrfs: make extent_range_clear_dirty_for_io return void
Does not return any errors, nor anything from the callgraph. There's a
BUG_ON but it's a sanity check and not an error condition we could
recover from.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
b5227c075b btrfs: make end_extent_writepage return void
Does not return any errors, nor anything from the callgraph.  The branch
in end_bio_extent_writepage has been skipped since
5fd0204355 ("Btrfs: finish ordered extents in their own thread").

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
a9d93e1778 btrfs: make extent_clear_unlock_delalloc return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
69ba39272c btrfs: make clear_extent_buffer_uptodate return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
09c25a8cda btrfs: make set_extent_buffer_uptodate return void
Does not return any errors, nor anything from the callgraph.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
David Sterba
4db8c528cd btrfs: remove a trivial helper btrfs_set_buffer_uptodate
Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-07 15:06:45 +01:00
Linus Torvalds
d8cd93ea67 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "A couple of fixes (-stable fodder) + dead code removal after the
  overlayfs fix.

  I agree that it's better to separate from the fix part to make
  backporting easier, but IMO it's not worth delaying said dead code
  removal until the next window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Don't reset ->total_link_count on nested calls of vfs_path_lookup()
  ovl: get rid of the dead code left from broken (and disabled) optimizations
  ovl: fix permission checking for setattr
2015-12-06 13:51:49 -08:00
Al Viro
2788cc47f4 Don't reset ->total_link_count on nested calls of vfs_path_lookup()
we already zero it on outermost set_nameidata(), so initialization in
path_init() is pointless and wrong.  The same DoS exists on pre-4.2
kernels, but there a slightly different fix will be needed.

Cc: stable@vger.kernel.org # v4.2
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06 12:33:02 -05:00
Al Viro
0f7ff2dabb ovl: get rid of the dead code left from broken (and disabled) optimizations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06 12:31:07 -05:00
Miklos Szeredi
acff81ec2c ovl: fix permission checking for setattr
[Al Viro] The bug is in being too enthusiastic about optimizing ->setattr()
away - instead of "copy verbatim with metadata" + "chmod/chown/utimes"
(with the former being always safe and the latter failing in case of
insufficient permissions) it tries to combine these two.  Note that copyup
itself will have to do ->setattr() anyway; _that_ is where the elevated
capabilities are right.  Having these two ->setattr() (one to set verbatim
copy of metadata, another to do what overlayfs ->setattr() had been asked
to do in the first place) combined is where it breaks.

Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-06 12:28:23 -05:00
Ilya Dryomov
43d1c0eb7e block: detach bdev inode from its wb in __blkdev_put()
Since 52ebea749a ("writeback: make backing_dev_info host
cgroup-specific bdi_writebacks") inode, at some point in its lifetime,
gets attached to a wb (struct bdi_writeback).  Detaching happens on
evict, in inode_detach_wb() called from __destroy_inode(), and involves
updating wb.

However, detaching an internal bdev inode from its wb in
__destroy_inode() is too late.  Its bdi and by extension root wb are
embedded into struct request_queue, which has different lifetime rules
and can be freed long before the final bdput() is called (can be from
__fput() of a corresponding /dev inode, through dput() - evict() -
bd_forget().  bdevs hold onto the underlying disk/queue pair only while
opened; as soon as bdev is closed all bets are off.  In fact,
disk/queue can be gone before __blkdev_put() even returns:

1499 static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
1500 {
...
1518         if (bdev->bd_contains == bdev) {
1519                 if (disk->fops->release)
1520                         disk->fops->release(disk, mode);

[ Driver puts its references to disk/queue ]

1521         }
1522         if (!bdev->bd_openers) {
1523                 struct module *owner = disk->fops->owner;
1524
1525                 disk_put_part(bdev->bd_part);
1526                 bdev->bd_part = NULL;
1527                 bdev->bd_disk = NULL;
1528                 if (bdev != bdev->bd_contains)
1529                         victim = bdev->bd_contains;
1530                 bdev->bd_contains = NULL;
1531
1532                 put_disk(disk);

[ We put ours, the queue is gone
  The last bdput() would result in a write to invalid memory ]

1533                 module_put(owner);
...
1539 }

Since bdev inodes are special anyway, detach them in __blkdev_put()
after clearing inode's dirty bits, turning the problematic
inode_detach_wb() in __destroy_inode() into a noop.

add_disk() grabs its disk->queue since 523e1d399c ("block: make
gendisk hold a reference to its queue"), so the old ->release comment
is removed in favor of the new inode_detach_wb() comment.

Cc: stable@vger.kernel.org # 4.2+, needs backporting
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Tested-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-12-04 11:02:17 -07:00
Junxiao Bi
087ffd4eae jbd2: fix null committed data return in undo_access
introduced jbd2_write_access_granted() to improve write|undo_access
speed, but missed to check the status of b_committed_data which caused
a kernel panic on ocfs2.

[ 6538.405938] ------------[ cut here ]------------
[ 6538.406686] kernel BUG at fs/ocfs2/suballoc.c:2400!
[ 6538.406686] invalid opcode: 0000 [#1] SMP
[ 6538.406686] Modules linked in: ocfs2 nfsd lockd grace nfs_acl auth_rpcgss sunrpc autofs4 ocfs2_dlmfs ocfs2_stack_o2cb ocfs2_dlm ocfs2_nodemanager ocfs2_stackglue configfs sd_mod sg ip6t_REJECT nf_reject_ipv6 nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables be2iscsi iscsi_boot_sysfs bnx2i cnic uio cxgb4i cxgb4 cxgb3i libcxgbi cxgb3 mdio ib_iser rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core ib_addr ipv6 iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ppdev xen_kbdfront xen_netfront xen_fbfront parport_pc parport pcspkr i2c_piix4 acpi_cpufreq ext4 jbd2 mbcache xen_blkfront floppy pata_acpi ata_generic ata_piix cirrus ttm drm_kms_helper drm fb_sys_fops sysimgblt sysfillrect i2c_core syscopyarea dm_mirror dm_region_hash dm_log dm_mod
[ 6538.406686] CPU: 1 PID: 16265 Comm: mmap_truncate Not tainted 4.3.0 #1
[ 6538.406686] Hardware name: Xen HVM domU, BIOS 4.3.1OVM 05/14/2014
[ 6538.406686] task: ffff88007c2bab00 ti: ffff880075b78000 task.ti: ffff880075b78000
[ 6538.406686] RIP: 0010:[<ffffffffa06a286b>]  [<ffffffffa06a286b>] ocfs2_block_group_clear_bits+0x23b/0x250 [ocfs2]
[ 6538.406686] RSP: 0018:ffff880075b7b7f8  EFLAGS: 00010246
[ 6538.406686] RAX: ffff8800760c5b40 RBX: ffff88006c06a000 RCX: ffffffffa06e6df0
[ 6538.406686] RDX: 0000000000000000 RSI: ffff88007a6f6ea0 RDI: ffff88007a760430
[ 6538.406686] RBP: ffff880075b7b878 R08: 0000000000000002 R09: 0000000000000001
[ 6538.406686] R10: ffffffffa06769be R11: 0000000000000000 R12: 0000000000000001
[ 6538.406686] R13: ffffffffa06a1750 R14: 0000000000000001 R15: ffff88007a6f6ea0
[ 6538.406686] FS:  00007f17fde30720(0000) GS:ffff88007f040000(0000) knlGS:0000000000000000
[ 6538.406686] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6538.406686] CR2: 0000000000601730 CR3: 000000007aea0000 CR4: 00000000000406e0
[ 6538.406686] Stack:
[ 6538.406686]  ffff88007c2bb5b0 ffff880075b7b8e0 ffff88007a7604b0 ffff88006c640800
[ 6538.406686]  ffff88007a7604b0 ffff880075d77390 0000000075b7b878 ffffffffa06a309d
[ 6538.406686]  ffff880075d752d8 ffff880075b7b990 ffff880075b7b898 0000000000000000
[ 6538.406686] Call Trace:
[ 6538.406686]  [<ffffffffa06a309d>] ? ocfs2_read_group_descriptor+0x6d/0xa0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a3654>] _ocfs2_free_suballoc_bits+0xe4/0x320 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a397e>] _ocfs2_free_clusters+0xee/0x210 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a1750>] ? ocfs2_put_slot+0xf0/0xf0 [ocfs2]
[ 6538.406686]  [<ffffffffa0682d50>] ? ocfs2_extend_trans+0x50/0x1a0 [ocfs2]
[ 6538.406686]  [<ffffffffa06a3ad5>] ocfs2_free_clusters+0x15/0x20 [ocfs2]
[ 6538.406686]  [<ffffffffa065072c>] ocfs2_replay_truncate_records+0xfc/0x290 [ocfs2]
[ 6538.406686]  [<ffffffffa06843ac>] ? ocfs2_start_trans+0xec/0x1d0 [ocfs2]
[ 6538.406686]  [<ffffffffa0654600>] __ocfs2_flush_truncate_log+0x140/0x2d0 [ocfs2]
[ 6538.406686]  [<ffffffffa0654394>] ? ocfs2_reserve_blocks_for_rec_trunc.clone.0+0x44/0x170 [ocfs2]
[ 6538.406686]  [<ffffffffa065acd4>] ocfs2_remove_btree_range+0x374/0x630 [ocfs2]
[ 6538.406686]  [<ffffffffa017486b>] ? jbd2_journal_stop+0x25b/0x470 [jbd2]
[ 6538.406686]  [<ffffffffa065d5b5>] ocfs2_commit_truncate+0x305/0x670 [ocfs2]
[ 6538.406686]  [<ffffffffa0683430>] ? ocfs2_journal_access_eb+0x20/0x20 [ocfs2]
[ 6538.406686]  [<ffffffffa067adb7>] ocfs2_truncate_file+0x297/0x380 [ocfs2]
[ 6538.406686]  [<ffffffffa01759e4>] ? jbd2_journal_begin_ordered_truncate+0x64/0xc0 [jbd2]
[ 6538.406686]  [<ffffffffa067c7a2>] ocfs2_setattr+0x572/0x860 [ocfs2]
[ 6538.406686]  [<ffffffff810e4a3f>] ? current_fs_time+0x3f/0x50
[ 6538.406686]  [<ffffffff812124b7>] notify_change+0x1d7/0x340
[ 6538.406686]  [<ffffffff8121abf9>] ? generic_getxattr+0x79/0x80
[ 6538.406686]  [<ffffffff811f5876>] do_truncate+0x66/0x90
[ 6538.406686]  [<ffffffff81120e30>] ? __audit_syscall_entry+0xb0/0x110
[ 6538.406686]  [<ffffffff811f5bb3>] do_sys_ftruncate.clone.0+0xf3/0x120
[ 6538.406686]  [<ffffffff811f5bee>] SyS_ftruncate+0xe/0x10
[ 6538.406686]  [<ffffffff816aa2ae>] entry_SYSCALL_64_fastpath+0x12/0x71
[ 6538.406686] Code: 28 48 81 ee b0 04 00 00 48 8b 92 50 fb ff ff 48 8b 80 b0 03 00 00 48 39 90 88 00 00 00 0f 84 30 fe ff ff 0f 0b eb fe 0f 0b eb fe <0f> 0b 0f 1f 00 eb fb 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
[ 6538.406686] RIP  [<ffffffffa06a286b>] ocfs2_block_group_clear_bits+0x23b/0x250 [ocfs2]
[ 6538.406686]  RSP <ffff880075b7b7f8>
[ 6538.691128] ---[ end trace 31cd7011d6770d7e ]---
[ 6538.694492] Kernel panic - not syncing: Fatal exception
[ 6538.695484] Kernel Offset: disabled

Fixes: de92c8caf16c("jbd2: speedup jbd2_journal_get_[write|undo]_access()")
Cc: <stable@vger.kernel.org>
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-12-04 12:29:28 -05:00
Linus Torvalds
071f5d105a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "A lot of Thanksgiving turkey leftovers accumulated, here goes:

   1) Fix bluetooth l2cap_chan object leak, from Johan Hedberg.

   2) IDs for some new iwlwifi chips, from Oren Givon.

   3) Fix rtlwifi lockups on boot, from Larry Finger.

   4) Fix memory leak in fm10k, from Stephen Hemminger.

   5) We have a route leak in the ipv6 tunnel infrastructure, fix from
      Paolo Abeni.

   6) Fix buffer pointer handling in arm64 bpf JIT,f rom Zi Shen Lim.

   7) Wrong lockdep annotations in tcp md5 support, fix from Eric
      Dumazet.

   8) Work around some middle boxes which prevent proper handling of TCP
      Fast Open, from Yuchung Cheng.

   9) TCP repair can do huge kmalloc() requests, build paged SKBs
      instead.  From Eric Dumazet.

  10) Fix msg_controllen overflow in scm_detach_fds, from Daniel
      Borkmann.

  11) Fix device leaks on ipmr table destruction in ipv4 and ipv6, from
      Nikolay Aleksandrov.

  12) Fix use after free in epoll with AF_UNIX sockets, from Rainer
      Weikusat.

  13) Fix double free in VRF code, from Nikolay Aleksandrov.

  14) Fix skb leaks on socket receive queue in tipc, from Ying Xue.

  15) Fix ifup/ifdown crach in xgene driver, from Iyappan Subramanian.

  16) Fix clearing of persistent array maps in bpf, from Daniel
      Borkmann.

  17) In TCP, for the cross-SYN case, we don't initialize tp->copied_seq
      early enough.  From Eric Dumazet.

  18) Fix out of bounds accesses in bpf array implementation when
      updating elements, from Daniel Borkmann.

  19) Fill gaps in RCU protection of np->opt in ipv6 stack, from Eric
      Dumazet.

  20) When dumping proxy neigh entries, we have to accomodate NULL
      device pointers properly, from Konstantin Khlebnikov.

  21) SCTP doesn't release all ipv6 socket resources properly, fix from
      Eric Dumazet.

  22) Prevent underflows of sch->q.qlen for multiqueue packet
      schedulers, also from Eric Dumazet.

  23) Fix MAC and unicast list handling in bnxt_en driver, from Jeffrey
      Huang and Michael Chan.

  24) Don't actively scan radar channels, from Antonio Quartulli"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (110 commits)
  net: phy: reset only targeted phy
  bnxt_en: Setup uc_list mac filters after resetting the chip.
  bnxt_en: enforce proper storing of MAC address
  bnxt_en: Fixed incorrect implementation of ndo_set_mac_address
  net: lpc_eth: remove irq > NR_IRQS check from probe()
  net_sched: fix qdisc_tree_decrease_qlen() races
  openvswitch: fix hangup on vxlan/gre/geneve device deletion
  ipv4: igmp: Allow removing groups from a removed interface
  ipv6: sctp: implement sctp_v6_destroy_sock()
  arm64: bpf: add 'store immediate' instruction
  ipv6: kill sk_dst_lock
  ipv6: sctp: add rcu protection around np->opt
  net/neighbour: fix crash at dumping device-agnostic proxy entries
  sctp: use GFP_USER for user-controlled kmalloc
  sctp: convert sack_needed and sack_generation to bits
  ipv6: add complete rcu protection around np->opt
  bpf: fix allocation warnings in bpf maps and integer overflow
  mvebu: dts: enable IP checksum with jumbo frames for Armada 38x on Port0
  net: mvneta: enable setting custom TX IP checksum limit
  net: mvneta: fix error path for building skb
  ...
2015-12-03 16:02:46 -08:00
Linus Torvalds
2873d32ff4 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
 "A collection of fixes from this series.  The most important here is a
  regression fix for an issue that some folks would hit in blk-merge.c,
  and the NVMe queue depth limit for the screwed up Apple "nvme"
  controller.

  In more detail, this pull request contains:

   - a set of fixes for null_blk, including a fix for a few corner cases
     where we could hang the device.  From Arianna and Paolo.

   - lightnvm:
        - A build improvement from Keith.
        - Update the qemu pci id detection from Matias.
        - Error handling fixes for leaks and other little fixes from
          Sudip and Wenwei.

   - fix from Eric where BLKRRPART would not return EBUSY for whole
     device mounts, only when partitions were mounted.

   - fix from Jan Kara, where EOF O_DIRECT reads would return
     negatively.

   - remove check for rq_mergeable() when checking limits for cloned
     requests.  The check doesn't make any sense.  It's assuming that
     since NOMERGE is set on the request that we don't have to
     recalculate limits since the request didn't change, but that's not
     true if the request has been redirected.  From Hannes.

   - correctly get the bio front segment value set for single segment
     bio's, fixing a BUG() in blk-merge.  From Ming"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: temporary fix for Apple controller reset
  null_blk: change type of completion_nsec to unsigned long
  null_blk: guarantee device restart in all irq modes
  null_blk: set a separate timer for each command
  blk-merge: fix computing bio->bi_seg_front_size in case of single segment
  direct-io: Fix negative return from dio read beyond eof
  block: Always check queue limits for cloned requests
  lightnvm: missing nvm_lock acquire
  lightnvm: unconverted ppa returned in get_bb_tbl
  lightnvm: refactor and change vendor id for qemu
  lightnvm: do device max sectors boundary check first
  lightnvm: fix ioctl memory leaks
  lightnvm: free memory when gennvm register fails
  lightnvm: Simplify config when disabled
  Return EBUSY from BLKRRPART for mounted whole-dev fs
2015-12-03 15:45:16 -08:00
David Sterba
39a27ec100 btrfs: use GFP_KERNEL for xattr and acl allocations
We don't have to use GFP_NOFS in context of ACL or XATTR actions, not
possible to loop through the allocator and it's safe to fail with
ENOMEM.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:03:44 +01:00
David Sterba
61dd5ae65b btrfs: use GFP_KERNEL for allocations of workqueues
We don't have to use GFP_NOFS to allocate workqueue structures, this is
done from mount context or potentially scrub start context, safe to fail
in both cases.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:03:43 +01:00
David Sterba
8d2db7855e btrfs: use GFP_KERNEL for allocations in ioctl handlers
We don't have to use GFP_NOFS in the ioctl handlers because there's no
risk of looping through the allocators back to the filesystem. This
patch covers only allocations that are directly in the ioctl handlers.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:03:43 +01:00
David Sterba
3042460136 btrfs: remove wait from struct btrfs_delalloc_work
The value is 0 and never changes, we can propagate the value, remove
wait and the implied dead code.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:02:21 +01:00
David Sterba
651d494a67 btrfs: sink parameter wait to btrfs_alloc_delalloc_work
There's only one caller and single value, we can propagate it down to
the callee and remove the unused parameter.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:02:21 +01:00
David Sterba
87ad58c5f0 btrfs: make btrfs_close_one_device static
Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:02:21 +01:00
David Sterba
cd716d8fea btrfs: make lock_extent static inline
One call less reduces stack usage, code slightly reduced as well.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:44:59 +01:00
David Sterba
ff13db41f1 btrfs: drop unused parameter from lock_extent_bits
We've always passed 0. Stack usage will slightly decrease.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:30:40 +01:00
David Sterba
e83b1d91f8 btrfs: make clear_extent_bit helpers static inline
The funcions just wrap the clear_extent_bit API and generate function
calls. This increases stack consumption and may negatively affect
performance due to icache misses. We can simply make the helpers static
inline and keep the type checking and API untouched. The code slightly
decreases:

   text	   data	    bss	    dec	    hex	filename
 938667	  43670	  23144	1005481	  f57a9	fs/btrfs/btrfs.ko.before
 939651	  43670	  23144	1006465	  f5b81	fs/btrfs/btrfs.ko.after

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:17:30 +01:00
David Sterba
c63179556a btrfs: make set_extent_bit helpers static inline
The funcions just wrap the set_extent_bit API and generate function
calls. This increases stack consumption and may negatively affect
performance due to icache misses. We can simply make the helpers static
inline and keep the type checking and API untouched. The code slightly
increases:

   text	   data	    bss	    dec	    hex	filename
 938427	  43670	  23144	1005241	  f56b9	fs/btrfs/btrfs.ko.before
 938667	  43670	  23144	1005481	  f57a9	fs/btrfs/btrfs.ko

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:08:11 +01:00
Eric Dumazet
9cd3e072b0 net: rename SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
This patch is a cleanup to make following patch easier to
review.

Goal is to move SOCK_ASYNC_NOSPACE and SOCK_ASYNC_WAITDATA
from (struct socket)->flags to a (struct socket_wq)->flags
to benefit from RCU protection in sock_wake_async()

To ease backports, we rename both constants.

Two new helpers, sk_set_bit(int nr, struct sock *sk)
and sk_clear_bit(int net, struct sock *sk) are added so that
following patch can change their implementation.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-01 15:45:05 -05:00
Jan Kara
74cedf9b6c direct-io: Fix negative return from dio read beyond eof
Assume a filesystem with 4KB blocks. When a file has size 1000 bytes and
we issue direct IO read at offset 1024, blockdev_direct_IO() reads the
tail of the last block and the logic for handling short DIO reads in
dio_complete() results in a return value -24 (1000 - 1024) which
obviously confuses userspace.

Fix the problem by bailing out early once we sample i_size and can
reliably check that direct IO read starts beyond i_size.

Reported-by: Avi Kivity <avi@scylladb.com>
Fixes: 9fe55eea7e
CC: stable@vger.kernel.org
CC: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
2015-11-30 10:15:42 -07:00
Linus Torvalds
8003a57356 NFS client bugfixes for Linux 4.4
Highlights include:
 
 Stable patches:
 - Fix a NFSv4 callback identifier leak that was also causing client crashes
 - Fix NFSv4 callback decoding issues when incoming requests are truncated
 - Don't declare the attribute cache valid when we call nfs_update_inode with
   an empty attribute structure.
 - Resend LAYOUTGET when there is a race that changes the seqid
 
 Bugfixes:
 - Fix a number of issues with the NFSv4.2 CLONE ioctl()
 - Properly set NFS v4.2 NFSDBG_FACILITY
 - NFSv4 referrals are broken; Cleanup FATTR4_WORD0_FS_LOCATIONS after
   decoding success
 - Use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
 - Ensure that attrcache is revalidated after a SETATTR
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJWWPeyAAoJEGcL54qWCgDy9/UQAKNTF09OeHxSqO7oXbM4x0hY
 8a8A4ostTshtu4g6OWxeqI4/89A5lOcdHAoM/KOr+2HzssKA6B9lU4+pzcKfFI+U
 d9WqKVEC3MZA1N4KR+fS5LhtQU62izGKH+CQ9+tHvvesZu+bIiQgQu/uMzKVh2Al
 cKdDu99UxrxNP3PFDCcBtxpBvy27akT+21P8RutG12tqGQkfa1715JIQl9bqgquY
 ZruukMsqamp+LbZlnowgvoaBLBVUo19v8zwI34uSfXwNbQS71xmAV52z7HVHaEFt
 A8HQzS/MaFtMKpq7HOZYEnHB6h8YaYTK4GmHcCCFXHtjXopvHo8LXA6vYLTNhJ8V
 SvLpUJzUWVcGDDQ75x6iX/APPMSq0gxJA4+AZryBer3k2EvKlUoRrP+hgxOIK7HT
 2joWoFFKVe8a5NBj4Pd5+x6dpDEnIvlqGdMQNuXFUiPvcA/l3Uc0gnWhauuqvrhy
 ePrLRcWoSikLlPWxq39DRzJjQUdyUhBWMcCRWkhNzsT6U6HDSip5j0BkUBXD7nlU
 FK9BM2zRHr7kQ5Aax497K9qJNZBWI94y/vFkR/hJg0Z/bVQBF45lGxGgNFbj8Kag
 gR/xcYC9plum1IFD7DcnVnJTxrDSftIsLS8bhjmknxC8Pcyur2jegZvoDXiFk1GF
 gXERq36Ej/4WyyGrNyWm
 =5aPD
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.4-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client bugfixes from Trond Myklebust:
 "Highlights include:

  Stable patches:
   - Fix a NFSv4 callback identifier leak that was also causing client
     crashes
   - Fix NFSv4 callback decoding issues when incoming requests are
     truncated
   - Don't declare the attribute cache valid when we call
     nfs_update_inode with an empty attribute structure.
   - Resend LAYOUTGET when there is a race that changes the seqid

  Bugfixes:
   - Fix a number of issues with the NFSv4.2 CLONE ioctl()
   - Properly set NFS v4.2 NFSDBG_FACILITY
   - NFSv4 referrals are broken; Cleanup FATTR4_WORD0_FS_LOCATIONS after
     decoding success
   - Use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
   - Ensure that attrcache is revalidated after a SETATTR"

* tag 'nfs-for-4.4-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  nfs4: resend LAYOUTGET when there is a race that changes the seqid
  nfs: if we have no valid attrs, then don't declare the attribute cache valid
  nfs: ensure that attrcache is revalidated after a SETATTR
  nfs4: limit callback decoding to received bytes
  nfs4: start callback_ident at idr 1
  nfs: use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
  NFS4: Cleanup FATTR4_WORD0_FS_LOCATIONS after decoding success
  NFS: Properly set NFS v4.2 NFSDBG_FACILITY
  nfs: reduce the amount of ifdefs for v4.2 in nfs4file.c
  nfs: use btrfs ioctl defintions for clone
  nfs: allow intra-file CLONE
  nfs: offer native ioctls even if CONFIG_COMPAT is set
  nfs: pass on count for CLONE operations
2015-11-27 17:22:47 -08:00
Linus Torvalds
80e0c505b2 Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This has Mark Fasheh's patches to fix quota accounting during subvol
  deletion, which we've been working on for a while now.  The patch is
  pretty small but it's a key fix.

  Otherwise it's a random assortment"

* 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: fix balance range usage filters in 4.4-rc
  btrfs: qgroup: account shared subtree during snapshot delete
  Btrfs: use btrfs_get_fs_root in resolve_indirect_ref
  btrfs: qgroup: fix quota disable during rescan
  Btrfs: fix race between cleaner kthread and space cache writeout
  Btrfs: fix scrub preventing unused block groups from being deleted
  Btrfs: fix race between scrub and block group deletion
  btrfs: fix rcu warning during device replace
  btrfs: Continue replace when set_block_ro failed
  btrfs: fix clashing number of the enhanced balance usage filter
  Btrfs: fix the number of transaction units needed to remove a block group
  Btrfs: use global reserve when deleting unused block group after ENOSPC
  Btrfs: tests: checking for NULL instead of IS_ERR()
  btrfs: fix signed overflows in btrfs_sync_file
2015-11-27 15:45:45 -08:00
Xu Cang
681c46b164 ext4: add "static" to ext4_seq_##name##_fops struct
to fix sparse warning, add static to ext4_seq_##name##_fops struct.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-11-26 15:52:24 -05:00
Al Viro
5a1c7f47da ext4: fix an endianness bug in ext4_encrypted_follow_link()
applying le32_to_cpu() to 16bit value is a bad idea...
    
Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-11-26 15:20:50 -05:00
Al Viro
e2c9e0b28e ext4: fix an endianness bug in ext4_encrypted_zeroout()
ex->ee_block is not host-endian (note that accesses of other fields
of *ex right next to that line go through the helpers that do proper
conversion from little-endian to host-endian; it might make sense
to add similar for ->ee_block to avoid reintroducing that kind of
bugs...)

Cc: stable@vger.kernel.org # v4.1+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-11-26 15:20:19 -05:00
Jeff Layton
4f2e9dce0c nfs4: resend LAYOUTGET when there is a race that changes the seqid
pnfs_layout_process will check the returned layout stateid against what
the kernel has in-core. If it turns out that the stateid we received is
older, then we should resend the LAYOUTGET instead of falling back to
MDS I/O.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:32:13 -05:00
Jeff Layton
c812012f9c nfs: if we have no valid attrs, then don't declare the attribute cache valid
If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:31:49 -05:00
Jeff Layton
616c319683 nfs: ensure that attrcache is revalidated after a SETATTR
If we get no post-op attributes back from a SETATTR operation, then no
attributes will of course be updated during the call to
nfs_update_inode.

We know however that the attributes are invalid at that point, since we
just changed some of them. At the very least, the ctime will be bogus.
If we get no post-op attributes back on the call, mark the attrcache
invalid to reflect that fact.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-25 15:24:30 -05:00
Holger Hoffstätte
dba72cb30b btrfs: fix balance range usage filters in 4.4-rc
There's a regression in 4.4-rc since commit bc3094673f
(btrfs: extend balance filter usage to take minimum and maximum) in that
existing (non-ranged) balance with -dusage=x no longer works; all chunks
are skipped.

After staring at the code for a while and wondering why a non-ranged
balance would even need min and max thresholds (..which then were not
set correctly, leading to the bug) I realized that the only problem
was the fact that the filter functions were named wrong, thanks to
patching copypasta. Simply renaming both functions lets the existing
btrfs-progs call balance with -dusage=x and now the non-ranged filter
function is invoked, properly using only a single chunk limit.

Signed-off-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Fixes: bc3094673f ("btrfs: extend balance filter usage to take minimum and maximum")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:27:33 -08:00
Mark Fasheh
82bd101b52 btrfs: qgroup: account shared subtree during snapshot delete
Commit 0ed4792 ('btrfs: qgroup: Switch to new extent-oriented qgroup
mechanism.') removed our qgroup accounting during
btrfs_drop_snapshot(). Predictably, this results in qgroup numbers
going bad shortly after a snapshot is removed.

Fix this by adding a dirty extent record when we encounter extents during
our shared subtree walk. This effectively restores the functionality we had
with the original shared subtree walking code in 1152651 (btrfs: qgroup:
account shared subtrees during snapshot delete).

The idea with the original patch (and this one) is that shared subtrees can
get skipped during drop_snapshot. The shared subtree walk then allows us a
chance to visit those extents and add them to the qgroup work for later
processing. This ultimately makes the accounting for drop snapshot work.

The new qgroup code nicely handles all the other extents during the tree
walk via the ref dec/inc functions so we don't have to add actions beyond
what we had originally.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:27:33 -08:00
Josef Bacik
2d9e977610 Btrfs: use btrfs_get_fs_root in resolve_indirect_ref
The backref code will look up the fs_root we're trying to resolve our indirect
refs for, unfortunately we use btrfs_read_fs_root_no_name, which returns -ENOENT
if the ref is 0.  This isn't helpful for the qgroup stuff with snapshot delete
as it won't be able to search down the snapshot we are deleting, which will
cause us to miss roots.  So use btrfs_get_fs_root and send false for check_ref
so we can always get the root we're looking for.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Justin Maggard
967ef5131e btrfs: qgroup: fix quota disable during rescan
There's a race condition that leads to a NULL pointer dereference if you
disable quotas while a quota rescan is running.  To fix this, we just need
to wait for the quota rescan worker to actually exit before tearing down
the quota structures.

Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana
036a9348dc Btrfs: fix race between cleaner kthread and space cache writeout
When a block group becomes unused and the cleaner kthread is currently
running, we can end up getting the current transaction aborted with error
-ENOENT when we try to commit the transaction, leading to the following
trace:

  [59779.258768] WARNING: CPU: 3 PID: 5990 at fs/btrfs/extent-tree.c:3740 btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]()
  [59779.272594] BTRFS: Transaction aborted (error -2)
  (...)
  [59779.291137] Call Trace:
  [59779.291621]  [<ffffffff812566f4>] dump_stack+0x4e/0x79
  [59779.292543]  [<ffffffff8104d0a6>] warn_slowpath_common+0x9f/0xb8
  [59779.293435]  [<ffffffffa04cb81f>] ? btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]
  [59779.295000]  [<ffffffff8104d107>] warn_slowpath_fmt+0x48/0x50
  [59779.296138]  [<ffffffffa04c2721>] ? write_one_cache_group.isra.32+0x77/0x82 [btrfs]
  [59779.297663]  [<ffffffffa04cb81f>] btrfs_write_dirty_block_groups+0x17c/0x214 [btrfs]
  [59779.299141]  [<ffffffffa0549b0d>] commit_cowonly_roots+0x1de/0x261 [btrfs]
  [59779.300359]  [<ffffffffa04dd5b6>] btrfs_commit_transaction+0x4c4/0x99c [btrfs]
  [59779.301805]  [<ffffffffa04b5df4>] btrfs_sync_fs+0x145/0x1ad [btrfs]
  [59779.302893]  [<ffffffff81196634>] sync_filesystem+0x7f/0x93
  (...)
  [59779.318186] ---[ end trace 577e2daff90da33a ]---

The following diagram illustrates a sequence of steps leading to this
problem:

       CPU 1                                             CPU 2

                           <at transaction N>

                                                        adds bg A to list
                                                        fs_info->unused_bgs

                                                        adds bg B to list
                                                        fs_info->unused_bgs

                           <transaction kthread
                            commits transaction N
                            and wakes up the
                            cleaner kthread>

  cleaner kthread
    delete_unused_bgs()

      sees bg A in list
      fs_info->unused_bgs

      btrfs_start_transaction()

                           <transaction N + 1 starts>

      deletes bg A

                                                        update_block_group(bg C)

                                                          --> adds bg C to list
                                                              fs_info->unused_bgs

      deletes bg B

      sees bg C in the list
      fs_info->unused_bgs

      btrfs_remove_chunk(bg C)
        btrfs_remove_block_group(bg C)

          --> checks if the block group
              is in a dirty list, and
              because it isn't now, it
              does nothing

          --> the block group item
              is deleted from the
              extent tree

                                                          --> adds bg C to list
                                                              transaction->dirty_bgs

                                                         some task calls
                                                         btrfs_commit_transaction(t N + 1)
                                                           commit_cowonly_roots()
                                                             btrfs_write_dirty_block_groups()
                                                               --> sees bg C in cur_trans->dirty_bgs
                                                               --> calls write_one_cache_group()
                                                                   which returns -ENOENT because
                                                                   it did not find the block group
                                                                   item in the extent tree
                                                               --> transaction aborte with -ENOENT
                                                                   because write_one_cache_group()
                                                                   returned that error

So fix this by adding a block group to the list of dirty block groups
before adding it to the list of unused block groups.

This happened on a stress test using fsstress plus concurrent calls to
fallocate 20G and truncate (releasing part of the space allocated with
fallocate).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana
758f2dfcf8 Btrfs: fix scrub preventing unused block groups from being deleted
Currently scrub can race with the cleaner kthread when the later attempts
to delete an unused block group, and the result is preventing the cleaner
kthread from ever deleting later the block group - unless the block group
becomes used and unused again. The following diagram illustrates that
race:

              CPU 1                                 CPU 2

 cleaner kthread
   btrfs_delete_unused_bgs()

     gets block group X from
     fs_info->unused_bgs and
     removes it from that list

                                             scrub_enumerate_chunks()

                                               searches device tree using
                                               its commit root

                                               finds device extent for
                                               block group X

                                               gets block group X from the tree
                                               fs_info->block_group_cache_tree
                                               (via btrfs_lookup_block_group())

                                               sets bg X to RO

     sees the block group is
     already RO and therefore
     doesn't delete it nor adds
     it back to unused list

So fix this by making scrub add the block group again to the list of
unused block groups if the block group is still unused when it finished
scrubbing it and it hasn't been removed already.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:22:08 -08:00
Filipe Manana
020d5b7366 Btrfs: fix race between scrub and block group deletion
Scrub can race with the cleaner kthread deleting block groups that are
unused (and with relocation too) leading to a failure with error -EINVAL
that gets returned to user space.

The following diagram illustrates how it happens:

              CPU 1                                 CPU 2

 cleaner kthread
   btrfs_delete_unused_bgs()

     gets block group X from
     fs_info->unused_bgs

     sets block group to RO

       btrfs_remove_chunk(bg X)

         deletes device extents

                                         scrub_enumerate_chunks()

                                           searches device tree using
                                           its commit root

                                           finds device extent for
                                           block group X

                                           gets block group X from the tree
                                           fs_info->block_group_cache_tree
                                           (via btrfs_lookup_block_group())

                                           sets bg X to RO (again)

          btrfs_remove_block_group(bg X)

            deletes block group from
            fs_info->block_group_cache_tree

            removes extent map from
            fs_info->mapping_tree

                                               scrub_chunk(offset X)

                                                 searches fs_info->mapping_tree
                                                 for extent map starting at
                                                 offset X

                                                    --> doesn't find any such
                                                        extent map
                                                    --> returns -EINVAL and scrub
                                                        errors out to userspace
                                                        with -EINVAL

Fix this by dealing with an extent map lookup failure as an indicator of
block group deletion.
Issue reproduced with fstest btrfs/071.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
David Sterba
31388ab2ed btrfs: fix rcu warning during device replace
The test btrfs/011 triggers a rcu warning
Reviewed-by: Anand Jain <anand.jain@oracle.com>

===============================
[ INFO: suspicious RCU usage. ]
4.4.0-rc1-default+ #286 Tainted: G        W
-------------------------------
fs/btrfs/volumes.c:1977 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
4 locks held by btrfs/28786:

0:  (&fs_info->dev_replace.lock_finishing_cancel_unmount){+.+...}, at: [<ffffffffa00bc785>] btrfs_dev_replace_finishing+0x45/0xa00 [btrfs]
1:  (uuid_mutex){+.+.+.}, at: [<ffffffffa00bc84f>] btrfs_dev_replace_finishing+0x10f/0xa00 [btrfs]
2:  (&fs_devs->device_list_mutex){+.+.+.}, at: [<ffffffffa00bc868>] btrfs_dev_replace_finishing+0x128/0xa00 [btrfs]
3:  (&fs_info->chunk_mutex){+.+...}, at: [<ffffffffa00bc87d>] btrfs_dev_replace_finishing+0x13d/0xa00 [btrfs]

stack backtrace:
CPU: 0 PID: 28786 Comm: btrfs Tainted: G        W       4.4.0-rc1-default+ #286
Hardware name: Intel Corporation SandyBridge Platform/To be filled by O.E.M., BIOS ASNBCPT1.86C.0031.B00.1006301607 06/30/2010
0000000000000001 ffff8800a07dfb48 ffffffff8141d47b 0000000000000001
0000000000000001 0000000000000000 ffff8801464a4f00 ffff8800a07dfb78
ffffffff810cd883 ffff880146eb9400 ffff8800a3698600 ffff8800a33fe220
Call Trace:
[<ffffffff8141d47b>] dump_stack+0x4f/0x74
[<ffffffff810cd883>] lockdep_rcu_suspicious+0x103/0x140
[<ffffffffa0071261>] btrfs_rm_dev_replace_remove_srcdev+0x111/0x130 [btrfs]
[<ffffffff810d354d>] ? trace_hardirqs_on+0xd/0x10
[<ffffffff81449536>] ? __percpu_counter_sum+0x66/0x80
[<ffffffffa00bcc15>] btrfs_dev_replace_finishing+0x4d5/0xa00 [btrfs]
[<ffffffffa00bc96e>] ? btrfs_dev_replace_finishing+0x22e/0xa00 [btrfs]
[<ffffffffa00a8795>] ? btrfs_scrub_dev+0x415/0x6d0 [btrfs]
[<ffffffffa003ea69>] ? btrfs_start_transaction+0x9/0x20 [btrfs]
[<ffffffffa00bda79>] btrfs_dev_replace_start+0x339/0x590 [btrfs]
[<ffffffff81196aa5>] ? __might_fault+0x95/0xa0
[<ffffffffa0078638>] btrfs_ioctl_dev_replace+0x118/0x160 [btrfs]
[<ffffffff811409c6>] ? stack_trace_call+0x46/0x70
[<ffffffffa007c914>] ? btrfs_ioctl+0x24/0x1770 [btrfs]
[<ffffffffa007ce43>] btrfs_ioctl+0x553/0x1770 [btrfs]
[<ffffffff811409c6>] ? stack_trace_call+0x46/0x70
[<ffffffff811d6eb1>] ? do_vfs_ioctl+0x21/0x5a0
[<ffffffff811d6f1c>] do_vfs_ioctl+0x8c/0x5a0
[<ffffffff811e3336>] ? __fget_light+0x86/0xb0
[<ffffffff811e3369>] ? __fdget+0x9/0x20
[<ffffffff811d7451>] ? SyS_ioctl+0x21/0x80
[<ffffffff811d7483>] SyS_ioctl+0x53/0x80
[<ffffffff81b1efd7>] entry_SYSCALL_64_fastpath+0x12/0x6f

This is because of unprotected use of rcu_dereference in
btrfs_scratch_superblocks. We can't add rcu locks around the whole
function because we read the superblock.

The fix will use the rcu string buffer directly without the rcu locking.
Thi is safe as the device will not go away in the meantime. We're
holding the device list mutexes.

Restructuring the code to narrow down the rcu section turned out to be
impossible, we need to call filp_open (through update_dev_time) on the
buffer and this could call kmalloc/__might_sleep. We could call kstrdup
with GFP_ATOMIC but it's not absolutely necessary.

Fixes: 12b1c2637b (Btrfs: enhance btrfs_scratch_superblock to scratch all superblocks)
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
Zhaolei
76a8efa171 btrfs: Continue replace when set_block_ro failed
xfstests/011 failed in node with small_size filesystem.
Can be reproduced by following script:
  DEV_LIST="/dev/vdd /dev/vde"
  DEV_REPLACE="/dev/vdf"

  do_test()
  {
      local mkfs_opt="$1"
      local size="$2"

      dmesg -c >/dev/null
      umount $SCRATCH_MNT &>/dev/null

      echo  mkfs.btrfs -f $mkfs_opt "${DEV_LIST[*]}"
      mkfs.btrfs -f $mkfs_opt "${DEV_LIST[@]}" || return 1
      mount "${DEV_LIST[0]}" $SCRATCH_MNT

      echo -n "Writing big files"
      dd if=/dev/urandom of=$SCRATCH_MNT/t0 bs=1M count=1 >/dev/null 2>&1
      for ((i = 1; i <= size; i++)); do
          echo -n .
          /bin/cp $SCRATCH_MNT/t0 $SCRATCH_MNT/t$i || return 1
      done
      echo

      echo Start replace
      btrfs replace start -Bf "${DEV_LIST[0]}" "$DEV_REPLACE" $SCRATCH_MNT || {
          dmesg
          return 1
      }
      return 0
  }

  # Set size to value near fs size
  # for example, 1897 can trigger this bug in 2.6G device.
  #
  ./do_test "-d raid1 -m raid1" 1897

System will report replace fail with following warning in dmesg:
 [  134.710853] BTRFS: dev_replace from /dev/vdd (devid 1) to /dev/vdf started
 [  135.542390] BTRFS: btrfs_scrub_dev(/dev/vdd, 1, /dev/vdf) failed -28
 [  135.543505] ------------[ cut here ]------------
 [  135.544127] WARNING: CPU: 0 PID: 4080 at fs/btrfs/dev-replace.c:428 btrfs_dev_replace_start+0x398/0x440()
 [  135.545276] Modules linked in:
 [  135.545681] CPU: 0 PID: 4080 Comm: btrfs Not tainted 4.3.0 #256
 [  135.546439] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.2-0-g33fbe13 by qemu-project.org 04/01/2014
 [  135.547798]  ffffffff81c5bfcf ffff88003cbb3d28 ffffffff817fe7b5 0000000000000000
 [  135.548774]  ffff88003cbb3d60 ffffffff810a88f1 ffff88002b030000 00000000ffffffe4
 [  135.549774]  ffff88003c080000 ffff88003c082588 ffff88003c28ab60 ffff88003cbb3d70
 [  135.550758] Call Trace:
 [  135.551086]  [<ffffffff817fe7b5>] dump_stack+0x44/0x55
 [  135.551737]  [<ffffffff810a88f1>] warn_slowpath_common+0x81/0xc0
 [  135.552487]  [<ffffffff810a89e5>] warn_slowpath_null+0x15/0x20
 [  135.553211]  [<ffffffff81448c88>] btrfs_dev_replace_start+0x398/0x440
 [  135.554051]  [<ffffffff81412c3e>] btrfs_ioctl+0x1d2e/0x25c0
 [  135.554722]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.555506]  [<ffffffff8111ab36>] ? current_kernel_time64+0x56/0xa0
 [  135.556304]  [<ffffffff81201e3d>] do_vfs_ioctl+0x30d/0x580
 [  135.557009]  [<ffffffff8114c7ba>] ? __audit_syscall_entry+0xaa/0xf0
 [  135.557855]  [<ffffffff810011d1>] ? do_audit_syscall_entry+0x61/0x70
 [  135.558669]  [<ffffffff8120d1c1>] ? __fget_light+0x61/0x90
 [  135.559374]  [<ffffffff81202124>] SyS_ioctl+0x74/0x80
 [  135.559987]  [<ffffffff81809857>] entry_SYSCALL_64_fastpath+0x12/0x6f
 [  135.560842] ---[ end trace 2a5c1fc3205abbdd ]---

Reason:
 When big data writen to fs, the whole free space will be allocated
 for data chunk.
 And operation as scrub need to set_block_ro(), and when there is
 only one metadata chunk in system(or other metadata chunks
 are all full), the function will try to allocate a new chunk,
 and failed because no space in device.

Fix:
 When set_block_ro failed for metadata chunk, it is not a problem
 because scrub_lock paused commit_trancaction in same time, and
 metadata are always cowed, so the on-the-fly writepages will not
 write data into same place with scrub/replace.
 Let replace continue in this case is no problem.

Tested by above script, and xfstests/011, plus 100 times xfstests/070.

Changelog v1->v2:
1: Add detail comments in source and commit-message.
2: Add dmesg detail into commit-message.
3: Limit return value of -ENOSPC to be passed.
All suggested by: Filipe Manana <fdmanana@gmail.com>

Suggested-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:51 -08:00
David Sterba
da02c68989 btrfs: fix clashing number of the enhanced balance usage filter
I've accidentally picked an already used number for the enhanced usage
filter represented by BTRFS_BALANCE_ARGS_USAGE_RANGE, clashing with
BTRFS_BALANCE_ARGS_CONVERT. Introduced during the development phase,
no backward compatibility issues.

Reported-by: Holger Hoffstätte <holger.hoffstaette@googlemail.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: bc3094673f ("btrfs: extend balance filter usage to take minimum and maximum")
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Filipe Manana
7fd01182d1 Btrfs: fix the number of transaction units needed to remove a block group
We were using only 1 transaction unit when attempting to delete an unused
block group but in reality we need 3 + N units, where N corresponds to the
number of stripes. We were accounting only for the addition of the orphan
item (for the block group's free space cache inode) but we were not
accounting that we need to delete one block group item from the extent
tree, one free space item from the tree of tree roots and N device extent
items from the device tree.

While one unit is not enough, it worked most of the time because for each
single unit we are too pessimistic and assume an entire tree path, with
the highest possible heigth (8), needs to be COWed with eventual node
splits at every possible level in the tree, so there was usually enough
reserved space for removing all the items and adding the orphan item.

However after adding the orphan item, writepages() can by called by the VM
subsystem against the btree inode when we are under memory pressure, which
causes writeback to start for the nodes we COWed before, this forces the
operation to remove the free space item to COW again some (or all of) the
same nodes (in the tree of tree roots). Even without writepages() being
called, we could fail with ENOSPC because these items are located in
multiple trees and one of them might have a higher heigth and require
node/leaf splits at many levels, exhausting all the reserved space before
removing all the items and adding the orphan.

In the kernel 4.0 release, commit 3d84be7991 ("Btrfs: fix BUG_ON in
btrfs_orphan_add() when delete unused block group"), we attempted to fix
a BUG_ON due to ENOSPC when trying to add the orphan item by making the
cleaner kthread reserve one transaction unit before attempting to remove
the block group, but this was not enough. We had a couple user reports
still hitting the same BUG_ON after 4.0, like Stefan Priebe's report on
a 4.2-rc6 kernel for example:

    http://www.spinics.net/lists/linux-btrfs/msg46070.html

So fix this by reserving all the necessary units of metadata.

Reported-by: Stefan Priebe <s.priebe@profihost.ag>
Fixes: 3d84be7991 ("Btrfs: fix BUG_ON in btrfs_orphan_add() when delete unused block group")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Filipe Manana
8eab77ff16 Btrfs: use global reserve when deleting unused block group after ENOSPC
It's possible to reach a state where the cleaner kthread isn't able to
start a transaction to delete an unused block group due to lack of enough
free metadata space and due to lack of unallocated device space to allocate
a new metadata block group as well. If this happens try to use space from
the global block group reserve just like we do for unlink operations, so
that we don't reach a permanent state where starting a transaction for
filesystem operations (file creation, renames, etc) keeps failing with
-ENOSPC. Such an unfortunate state was observed on a machine where over
a dozen unused data block groups existed and the cleaner kthread was
failing to delete them due to ENOSPC error when attempting to start a
transaction, and even running balance with a -dusage=0 filter failed with
ENOSPC as well. Also unmounting and mounting again the filesystem didn't
help. Allowing the cleaner kthread to use the global block reserve to
delete the unused data block groups fixed the problem.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Dan Carpenter
89b6c8d1e4 Btrfs: tests: checking for NULL instead of IS_ERR()
btrfs_alloc_dummy_root() return an error pointer on failure, it never
returns NULL.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
David Sterba
9dcbeed4d7 btrfs: fix signed overflows in btrfs_sync_file
The calculation of range length in btrfs_sync_file leads to signed
overflow. This was caught by PaX gcc SIZE_OVERFLOW plugin.

https://forums.grsecurity.net/viewtopic.php?f=1&t=4284

The fsync call passes 0 and LLONG_MAX, the range length does not fit to
loff_t and overflows, but the value is converted to u64 so it silently
works as expected.

The minimal fix is a typecast to u64, switching functions to take
(start, end) instead of (start, len) would be more intrusive.

Coccinelle script found that there's one more opencoded calculation of
the length.

<smpl>
@@
loff_t start, end;
@@
* end - start
</smpl>

CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-11-25 05:19:50 -08:00
Jan Kara
bc23f0c8d7 jbd2: Fix unreclaimed pages after truncate in data=journal mode
Ted and Namjae have reported that truncated pages don't get timely
reclaimed after being truncated in data=journal mode. The following test
triggers the issue easily:

for (i = 0; i < 1000; i++) {
	pwrite(fd, buf, 1024*1024, 0);
	fsync(fd);
	fsync(fd);
	ftruncate(fd, 0);
}

The reason is that journal_unmap_buffer() finds that truncated buffers
are not journalled (jh->b_transaction == NULL), they are part of
checkpoint list of a transaction (jh->b_cp_transaction != NULL) and have
been already written out (!buffer_dirty(bh)). We clean such buffers but
we leave them in the checkpoint list. Since checkpoint transaction holds
a reference to the journal head, these buffers cannot be released until
the checkpoint transaction is cleaned up. And at that point we don't
call release_buffer_page() anymore so pages detached from mapping are
lingering in the system waiting for reclaim to find them and free them.

Fix the problem by removing buffers from transaction checkpoint lists
when journal_unmap_buffer() finds out they don't have to be there
anymore.

Reported-and-tested-by: Namjae Jeon <namjae.jeon@samsung.com>
Fixes: de1b794130
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
2015-11-24 15:34:35 -05:00
David Turner
a4dad1ae24 ext4: Fix handling of extended tv_sec
In ext4, the bottom two bits of {a,c,m}time_extra are used to extend
the {a,c,m}time fields, deferring the year 2038 problem to the year
2446.

When decoding these extended fields, for times whose bottom 32 bits
would represent a negative number, sign extension causes the 64-bit
extended timestamp to be negative as well, which is not what's
intended.  This patch corrects that issue, so that the only negative
{a,c,m}times are those between 1901 and 1970 (as per 32-bit signed
timestamps).

Some older kernels might have written pre-1970 dates with 1,1 in the
extra bits.  This patch treats those incorrectly-encoded dates as
pre-1970, instead of post-2311, until kernel 4.20 is released.
Hopefully by then e2fsck will have fixed up the bad data.

Also add a comment explaining the encoding of ext4's extra {a,c,m}time
bits.

Signed-off-by: David Turner <novalis@novalis.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reported-by: Mark Harris <mh8928@yahoo.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=23732
Cc: stable@vger.kernel.org
2015-11-24 14:34:37 -05:00
Benjamin Coddington
38b7631fbe nfs4: limit callback decoding to received bytes
A truncated cb_compound request will cause the client to decode null or
data from a previous callback for nfs4.1 backchannel case, or uninitialized
data for the nfs4.0 case. This is because the path through
svc_process_common() advances the request's iov_base and decrements iov_len
without adjusting the overall xdr_buf's len field.  That causes
xdr_init_decode() to set up the xdr_stream with an incorrect length in
nfs4_callback_compound().

Fixing this for the nfs4.1 backchannel case first requires setting the
correct iov_len and page_len based on the length of received data in the
same manner as the nfs4.0 case.

Then the request's xdr_buf length can be adjusted for both cases based upon
the remaining iov_len and page_len.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-23 22:03:15 -05:00
Benjamin Coddington
c68a027c05 nfs4: start callback_ident at idr 1
If clp->cl_cb_ident is zero, then nfs_cb_idr_remove_locked() skips removing
it when the nfs_client is freed.  A decoding or server bug can then find
and try to put that first nfs_client which would lead to a crash.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: d687031265 ("nfs4client: convert to idr_alloc()")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-23 21:59:42 -05:00
Jeff Layton
91ab4b4d16 nfs: use sliding delay when LAYOUTGET gets NFS4ERR_DELAY
When LAYOUTGET gets NFS4ERR_DELAY, we currently will wait 15s before
retrying the call. That is a _very_ long time, so add a timeout value to
struct nfs4_layoutget and pass nfs4_async_handle_error a pointer to it.
This allows the RPC engine to use a sliding delay window, instead of a
15s delay.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-11-23 21:57:44 -05:00