write_cache_pages tries to build up a large bio to stuff down the pipe.
But if it needs to wait for a page lock, it needs to make sure and send
down any pending writes so we don't deadlock with anyone who has the
page lock and is waiting for writeback of things inside the bio.

Dave Sterba triggered this as a deadlock between the autodefrag code and
the extent write_cache_pages
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The tree log had two important bugs that could cause corruptions after a
crash.  Sometimes we were allowing tree log blocks to be reused after
the tree log was committed but before the transaction commit was done.

This allowed a future metadata write to overwrite the tree log data.  It
is fixed by adding a new variant of freeing reserved extents that always
pins them.  Credit goes to Stefan Behrens and Arne Jansen for many many
hours spent tracking this bug down.

During tree log replay, we do a pass through the tree log and pin all
the extents we find.  This makes sure the replay code won't go in and
use any of those blocks for new allocations during replay.  The problem
is the free space cache isn't honoring these pinned extents.  So the
allocator can end up handing them out, leading to all kinds of problems
during replay.

The fix here is to force any free space cache to load while we pin the
extents, and then to make sure we remove the pinned extents from the
free space rbtree.
Signed-off-by: NChris Mason <chris.mason@oracle.com>
Reported-by: NStefan Behrens <sbehrens@giantdisaster.de>

btrfs_remove_free_space needs to make sure to set ret back to a
valid return value after setting it to EAGAIN, otherwise we return
it to the callers.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

When we're doing log commits, we try to wait for more writers to come in
and make the commit bigger.  This helps improve performance on rotating
disks, but on SSDs it adds latencies.
Signed-off-by: NChris Mason <chris.mason@oracle.com>

The WARN_ON under some circumstances heavily polute log and slow down
the machine. This is just a safety, as the warning should be fixed by
another patch, nevertheless, it still pops up during testing.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>

There's a missing test whether the path passed to subvol=path option
during mount is a real subvolume, allowing any directory located in
default subovlume to be passed and accepted for mount.

(current btrfs progs prevent this early)
$ btrfs subvol snapshot . p1-snap
ERROR: '.' is not a subvolume

(with "is subvolume?" test bypassed)
$ btrfs subvol snapshot . p1-snap
Create a snapshot of '.' in './p1-snap'

$ btrfs subvol list -p .
ID 258 parent 5 top level 5 path subvol
ID 259 parent 5 top level 5 path subvol1
ID 260 parent 5 top level 5 path default-subvol1
ID 262 parent 5 top level 5 path p1/p1-snapshot
ID 263 parent 259 top level 5 path subvol1/subvol1-snap

The problem I see is that this makes a false impression of snapshotting the
given subvolume but in fact snapshots the default one: a user expects outcome
like ID 263 but in fact gets ID 262 .

This patch makes mount fail with EINVAL with a message in syslog.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>

* git://git.infradead.org/iommu-2.6:
  intel-iommu: fix superpage support in pfn_to_dma_pte()
  intel-iommu: set iommu_superpage on VM domains to lowest common denominator
  intel-iommu: fix return value of iommu_unmap() API
  MAINTAINERS: Update VT-d entry for drivers/pci -> drivers/iommu move
  intel-iommu: Export a flag indicating that the IOMMU is used for iGFX.
  intel-iommu: Workaround IOTLB hang on Ironlake GPU
  intel-iommu: Fix AB-BA lockdep report

* 'for-linus' of http://people.redhat.com/agk/git/linux-dm:
  dm kcopyd: fix job_pool leak

Commit 4b239f45 ("x86-64, mm: Put early page table high") causes a S4
regression since 2.6.39, namely the machine reboots occasionally at S4
resume.  It doesn't happen always, overall rate is about 1/20.  But,
like other bugs, once when this happens, it continues to happen.

This patch fixes the problem by essentially reverting the memory
assignment in the older way.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Yinghai Lu <yinghai.lu@oracle.com>
[ We'll hopefully find the real fix, but that's too late for 3.1 now ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix memory leak introduced by commit a6e50b40
(dm snapshot: skip reading origin when overwriting complete chunk).

When allocating a set of jobs from kc->job_pool, job->master_job must be
set (to point to itself) so that the mempool item gets freed when the
master_job completes.

master_job was introduced by commit c6ea41fb
(dm kcopyd: preallocate sub jobs to avoid deadlock)
Reported-by: NMichael Leun <ml@newton.leun.net>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: NAlasdair G Kergon <agk@redhat.com>

* 'samsung-fixes-4' of git://github.com/kgene/linux-samsung:
  ARM: S3C24XX: Fix s3c24xx build errors if !CONFIG_PM
  ARM: S5P: fix offset calculation on gpio-interrupt

Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (w83627ehf) Fix negative 8-bit temperature values

v2:
- register_syscore_ops(&s3c24xx_irq_syscore_ops) does not need to be
  conditionally compiled out, it is already optimized out on !CONFIG_PM
- fix also s3c2412 and s3c2416 affected by the same build issue

v1:
s3c2440.c fails to build if !CONFIG_PM because in such case
s3c2410_pm_syscore_ops is not defined. Same error should happen also
in s3c2410.c and s3c2442.c
Signed-off-by: NDomenico Andreoli <cavokz@gmail.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

* git://github.com/herbertx/crypto:
  crypto: ghash - Avoid null pointer dereference if no key is set

* 'fix/hda' of git://github.com/tiwai/sound:
  ALSA: HDA: conexant support for Lenovo T520/W520
  ALSA: hda - Add position_fix quirk for Dell Inspiron 1010

The ghash_update function passes a pointer to gf128mul_4k_lle which will
be NULL if ghash_setkey is not called or if the most recent call to
ghash_setkey failed to allocate memory.  This causes an oops.  Fix this
up by returning an error code in the null case.

This is trivially triggered from unprivileged userspace through the
AF_ALG interface by simply writing to the socket without setting a key.

The ghash_final function has a similar issue, but triggering it requires
a memory allocation failure in ghash_setkey _after_ at least one
successful call to ghash_update.

  BUG: unable to handle kernel NULL pointer dereference at 00000670
  IP: [<d88c92d4>] gf128mul_4k_lle+0x23/0x60 [gf128mul]
  *pde = 00000000
  Oops: 0000 [#1] PREEMPT SMP
  Modules linked in: ghash_generic gf128mul algif_hash af_alg nfs lockd nfs_acl sunrpc bridge ipv6 stp llc

  Pid: 1502, comm: hashatron Tainted: G        W   3.1.0-rc9-00085-ge9308cfd #32 Bochs Bochs
  EIP: 0060:[<d88c92d4>] EFLAGS: 00000202 CPU: 0
  EIP is at gf128mul_4k_lle+0x23/0x60 [gf128mul]
  EAX: d69db1f0 EBX: d6b8ddac ECX: 00000004 EDX: 00000000
  ESI: 00000670 EDI: d6b8ddac EBP: d6b8ddc8 ESP: d6b8dda4
   DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
  Process hashatron (pid: 1502, ti=d6b8c000 task=d6810000 task.ti=d6b8c000)
  Stack:
   00000000 d69db1f0 00000163 00000000 d6b8ddc8 c101a520 d69db1f0 d52aa000
   00000ff0 d6b8dde8 d88d310f d6b8a3f8 d52aa000 00001000 d88d502c d6b8ddfc
   00001000 d6b8ddf4 c11676ed d69db1e8 d6b8de24 c11679ad d52aa000 00000000
  Call Trace:
   [<c101a520>] ? kmap_atomic_prot+0x37/0xa6
   [<d88d310f>] ghash_update+0x85/0xbe [ghash_generic]
   [<c11676ed>] crypto_shash_update+0x18/0x1b
   [<c11679ad>] shash_ahash_update+0x22/0x36
   [<c11679cc>] shash_async_update+0xb/0xd
   [<d88ce0ba>] hash_sendpage+0xba/0xf2 [algif_hash]
   [<c121b24c>] kernel_sendpage+0x39/0x4e
   [<d88ce000>] ? 0xd88cdfff
   [<c121b298>] sock_sendpage+0x37/0x3e
   [<c121b261>] ? kernel_sendpage+0x4e/0x4e
   [<c10b4dbc>] pipe_to_sendpage+0x56/0x61
   [<c10b4e1f>] splice_from_pipe_feed+0x58/0xcd
   [<c10b4d66>] ? splice_from_pipe_begin+0x10/0x10
   [<c10b51f5>] __splice_from_pipe+0x36/0x55
   [<c10b4d66>] ? splice_from_pipe_begin+0x10/0x10
   [<c10b6383>] splice_from_pipe+0x51/0x64
   [<c10b63c2>] ? default_file_splice_write+0x2c/0x2c
   [<c10b63d5>] generic_splice_sendpage+0x13/0x15
   [<c10b4d66>] ? splice_from_pipe_begin+0x10/0x10
   [<c10b527f>] do_splice_from+0x5d/0x67
   [<c10b6865>] sys_splice+0x2bf/0x363
   [<c129373b>] ? sysenter_exit+0xf/0x16
   [<c104dc1e>] ? trace_hardirqs_on_caller+0x10e/0x13f
   [<c129370c>] sysenter_do_call+0x12/0x32
  Code: 83 c4 0c 5b 5e 5f c9 c3 55 b9 04 00 00 00 89 e5 57 8d 7d e4 56 53 8d 5d e4 83 ec 18 89 45 e0 89 55 dc 0f b6 70 0f c1 e6 04 01 d6 <f3> a5 be 0f 00 00 00 4e 89 d8 e8 48 ff ff ff 8b 45 e0 89 da 0f
  EIP: [<d88c92d4>] gf128mul_4k_lle+0x23/0x60 [gf128mul] SS:ESP 0068:d6b8dda4
  CR2: 0000000000000670
  ---[ end trace 4eaa2a86a8e2da24 ]---
  note: hashatron[1502] exited with preempt_count 1
  BUG: scheduling while atomic: hashatron/1502/0x10000002
  INFO: lockdep is turned off.
  [...]
Signed-off-by: NNick Bowler <nbowler@elliptictech.com>
Cc: stable@kernel.org [2.6.37+]
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

Offsets of the irq controller registers were calculated
correctly only for first GPIO bank. This patch fixes
calculation of the register offsets for all GPIO banks.
Reported-by: NSylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: NMarek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: NKyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Add alignment flag to PCI expansion resources
  sparc: Avoid calling sigprocmask()
  sparc: Use set_current_blocked()
  sparc32,leon: SRMMU MMU Table probe fix

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  fib_rules: fix unresolved_rules counting
  r8169: fix wrong eee setting for rlt8111evl
  r8169: fix driver shutdown WoL regression.
  ehea: Change maintainer to me
  pptp: pptp_rcv_core() misses pskb_may_pull() call
  tproxy: copy transparent flag when creating a time wait
  pptp: fix skb leak in pptp_xmit()
  bonding: use local function pointer of bond->recv_probe in bond_handle_frame
  smsc911x: Add support for SMSC LAN89218
  tg3: negate USE_PHYLIB flag check
  netconsole: enable netconsole can make net_device refcnt incorrent
  bluetooth: Properly clone LSM attributes to newly created child connections
  l2tp: fix a potential skb leak in l2tp_xmit_skb()
  bridge: fix hang on removal of bridge via netlink
  x25: Prevent skb overreads when checking call user data
  x25: Handle undersized/fragmented skbs
  x25: Validate incoming call user data lengths
  udplite: fast-path computation of checksum coverage
  IPVS netns shutdown/startup dead-lock
  netfilter: nf_conntrack: fix event flooding in GRE protocol tracker

Fix a bug introduced by 20b45077.  We have to return EINVAL on mount
failure, but doing that too early in the sequence leaves all of the
devices opened exclusively.  This also fixes an issue where under some
scenarios only a second mount -o degraded <devices> command would
succeed.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Initialize fs_info->bdev_holder a bit earlier to be able to pass a
correct holder id to blkdev_get() when opening seed devices with O_EXCL.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

If lookup_extent_backref fails, path->nodes[0] reasonably could be
null along with other callers of btrfs_print_leaf, so ensure we have a
valid extent buffer before dereferencing.
Signed-off-by: NDaniel J Blueman <daniel.blueman@gmail.com>

The task may fail to get free space though it is enough when multi-task
space allocation and caching space happen at the same time.

	Task1			Caching Thread		Task2
	------------------------------------------------------------------------
	find_free_extent
	  The space has not
	  be cached, and start
	  caching thread. And
	  wait for it.
				cache space, if
				the space is > 2MB
				wake up Task1
							find_free_extent
							  get all the space that
							  is cached.
	  try to allocate space,
	  but there is no space
	  now.
	trigger BUG_ON()

The message is following:
btrfs allocation failed flags 1, wanted 4096
space_info has 1040187392 free, is not full
space_info total=1082130432, used=4096, pinned=41938944, reserved=0, may_use=40828928, readonly=0
block group 12582912 has 8388608 bytes, 0 used 8388608 pinned 0 reserved
block group has cluster?: no
0 blocks of free space at or bigger than bytes is
block group 1103101952 has 1073741824 bytes, 4096 used 33550336 pinned 0 reserved
block group has cluster?: no
0 blocks of free space at or bigger than bytes is
------------[ cut here ]------------
kernel BUG at fs/btrfs/inode.c:835!
 [<ffffffffa031261b>] __extent_writepage+0x1bf/0x5ce [btrfs]
 [<ffffffff810cbcb8>] ? __set_page_dirty_nobuffers+0xfe/0x108
 [<ffffffffa02f8ada>] ? wait_current_trans+0x23/0xec [btrfs]
 [<ffffffff810c3fbf>] ? find_get_pages_tag+0x73/0xe2
 [<ffffffffa0312d12>] extent_write_cache_pages.clone.0+0x176/0x29a [btrfs]
 [<ffffffffa0312e74>] extent_writepages+0x3e/0x53 [btrfs]
 [<ffffffff8110ad2c>] ? do_sync_write+0xc6/0x103
 [<ffffffffa0302d6e>] ? btrfs_submit_direct+0x414/0x414 [btrfs]
 [<ffffffff811380fa>] ? fsnotify+0x236/0x266
 [<ffffffffa02fc930>] btrfs_writepages+0x22/0x24 [btrfs]
 [<ffffffff810cc215>] do_writepages+0x1c/0x25
 [<ffffffff810c4958>] __filemap_fdatawrite_range+0x4e/0x50
 [<ffffffff810c4982>] filemap_write_and_wait_range+0x28/0x51
 [<ffffffffa0306b2e>] btrfs_sync_file+0x7d/0x198 [btrfs]
 [<ffffffff8110aa26>] ? fsnotify_modify+0x5d/0x65
 [<ffffffff8112d150>] vfs_fsync_range+0x18/0x21
 [<ffffffff8112d170>] vfs_fsync+0x17/0x19
 [<ffffffff8112d316>] do_fsync+0x29/0x3e
 [<ffffffff8112d348>] sys_fsync+0xb/0xf
 [<ffffffff81468352>] system_call_fastpath+0x16/0x1b
[SNIP]
RIP  [<ffffffffa02fe08c>] cow_file_range+0x1c4/0x32b [btrfs]

We fix this bug by trying to allocate the space again if there are block groups
in caching.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>

In btrfs_get_acl(), when the second __btrfs_getxattr() call fails,
acl is not correctly set.
Therefore, a wrong value might return to the caller.
Signed-off-by: NTsutomu Itoh <t-itoh@jp.fujitsu.com>

Free space items are located in tree of tree roots, not in the extent
tree.  It didn't pop up because lookup_free_space_inode() grabs the
inode all the time instead of actually searching the tree.
Signed-off-by: NIlya Dryomov <idryomov@gmail.com>

Signed-off-by: NLiu Bo <liubo2009@cn.fujitsu.com>

To reproduce the bug:

  # mount -o nodatacow /dev/sda7 /mnt/
  # dd if=/dev/zero of=/mnt/tmp bs=4K count=1
  1+0 records in
  1+0 records out
  4096 bytes (4.1 kB) copied, 0.000136115 s, 30.1 MB/s
  # dd if=/dev/zero of=/mnt/tmp bs=4K count=1 conv=notrunc oflag=direct
  dd: writing `/mnt/tmp': Input/output error
  1+0 records in
  0+0 records out

btrfs_ordered_update_i_size() may return 1, but btrfs_endio_direct_write()
mistakenly takes it as an error.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

It's not a big deal if we fail to allocate the array, and instead of
panic we can just give up compressing.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

Otherwise we can execced the array bound of path->slots[].
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

We should retirn EINVAL if the start is beyond the end of the file
system in the btrfs_ioctl_fitrim(). Fix that by adding the appropriate
check for it.

Also in the btrfs_trim_fs() it is possible that len+start might overflow
if big values are passed. Fix it by decrementing the len so that start+len
is equal to the file system size in the worst case.
Signed-off-by: NLukas Czerner <lczerner@redhat.com>

We won't defrag an extent, if it's bigger than the threshold we
specified and there's no small extent before it, but actually
the code doesn't work this way.

There are three bugs:

- When should_defrag_range() decides we should keep on defragmenting
  an extent, last_len is not incremented. (old bug)

- The length that passes to should_defrag_range() is not the length
  we're going to defrag. (new bug)

- We always defrag 256K bytes data, and a big extent can be part of
  this range. (new bug)

For a file with 4 extents:

        | 4K | 4K | 256K | 256K |

The result of defrag with (the default) 256K extent thresh should be:

        | 264K | 256K |

but with those bugs, we'll get:

        | 520K |
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

Signed-off-by: NJie Liu <jeff.liu@oracle.com>

It's off-by-one, and thus we may skip the last page while defragmenting.

An example case:

  # create /mnt/file with 2 4K file extents
  # btrfs fi defrag /mnt/file
  # sync
  # filefrag /mnt/file
  /mnt/file: 2 extents found

So it's not defragmented.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

Don't use inode->i_size directly, since we're not holding i_mutex.

This also fixes another bug, that i_size can change after it's checked
against 0 and then (i_size - 1) can be negative.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

There's an off-by-one bug:

  # create a file with lots of 4K file extents
  # btrfs fi defrag /mnt/file
  # sync
  # filefrag -v /mnt/file
  Filesystem type is: 9123683e
  File size of /mnt/file is 1228800 (300 blocks, blocksize 4096)
   ext logical physical expected length flags
     0       0     3372              64
     1      64     3136     3435      1
     2      65     3436     3136     64
     3     129     3201     3499      1
     4     130     3500     3201     64
     5     194     3266     3563      1
     6     195     3564     3266     64
     7     259     3331     3627      1
     8     260     3628     3331     40 eof

After this patch:

  ...
  # filefrag -v /mnt/file
  Filesystem type is: 9123683e
  File size of /mnt/file is 1228800 (300 blocks, blocksize 4096)
   ext logical physical expected length flags
     0       0     3372             300 eof
  /mnt/file: 1 extent found
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>

kmemleak found this:
unreferenced object 0xffff8801b64af968 (size 512):
  comm "btrfs-cleaner", pid 3317, jiffies 4306810886 (age 903.272s)
  hex dump (first 32 bytes):
    00 82 01 07 00 ea ff ff c0 83 01 07 00 ea ff ff  ................
    80 82 01 07 00 ea ff ff c0 87 01 07 00 ea ff ff  ................
  backtrace:
    [<ffffffff816875cc>] kmemleak_alloc+0x5c/0xc0
    [<ffffffff8114aec3>] kmem_cache_alloc_trace+0x163/0x240
    [<ffffffff8127a290>] btrfs_defrag_file+0xf0/0xb20
    [<ffffffff8125d9a5>] btrfs_run_defrag_inodes+0x165/0x210
    [<ffffffff812479d7>] cleaner_kthread+0x177/0x190
    [<ffffffff81075c7d>] kthread+0x8d/0xa0
    [<ffffffff816af5f4>] kernel_thread_helper+0x4/0x10
    [<ffffffffffffffff>] 0xffffffffffffffff

"pages" is not always freed. Fix it removing the unnecesary additional return.
Signed-off-by: NDiego Calleja <diegocg@gmail.com>

Offset field in data extent backref can underflow if clone range ioctl
is used. We can reliably detect the underflow because max file size is
limited to 2^63 and max data extent size is limited by block group size.
Signed-off-by: NZheng Yan  <zheng.z.yan@intel.com>