smatch analysis indicates a number of redundant NULL checks before
calling kfree(), eg:

  fs/ocfs2/alloc.c:6138 ocfs2_begin_truncate_log_recovery() info:
   redundant null check on *tl_copy calling kfree()

  fs/ocfs2/alloc.c:6755 ocfs2_zero_range_for_truncate() info:
   redundant null check on pages calling kfree()

etc....

[akpm@linux-foundation.org: revert dubious change in ocfs2_begin_truncate_log_recovery()]
Signed-off-by: NTim Gardner <tim.gardner@canonical.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Acked-by: NJoel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The dereference should be moved below the NULL test.

spatch with a semantic match is used to found this.
(http://coccinelle.lip6.fr/)
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We found that bdev->bd_invalidated was left set once revalidate_disk()
is called, which results in page cache flush every time that device is
open.

Specifically, we found this problem in MD block device.  Once we resize
a MD device, mdadm --monitor periodically flush all page cache for that
device every 60 or 1000 seconds when it opens the device.

This bug lies since at least 3.2.0 till the latest kernel(3.6.2).  Patch
is attached.

The following steps will reproduce the problem.

1. prepair a block device (eg /dev/sdb).

2. create two partitions:

   sudo parted /dev/sdb
   mklabel gpt
   mkpart primary 0% 50%
   mkpart primary 50% 100%

3. create a md device.

   sudo mdadm -C /dev/md/hoge -l 1 -n 2 -e 1.2 --assume-clean --auto=md --symlink=no /dev/sdb1 /dev/sdb2

4. create file system and mount it

   sudo mkfs.ext3 /dev/md/hoge
   sudo mkdir /mnt/test
   sudo mount /dev/md/hoge /mnt/test

5. try to resize the device

   sudo mdadm -G /dev/md/hoge --size=max

6. create a file to fill file cache.

  sudo dd if=/dev/urandom of=/mnt/test/data bs=1M count=10

and verify the current status of file by free command.

7. mdadm monitor will open the md device every 1000 seconds and you
   will find all file cache on the device are cleared.

The timing can be reduced by the following steps.

a) kill mdadm and restart it with --delay option

   /sbin/mdadm --monitor --delay=30 --pid-file /var/run/mdadm/monitor.pid --daemonise --scan --syslog

or open the md device directly.

   sudo dd if=/dev/md/hoge of=/dev/null bs=4096 count=1
Signed-off-by: NMITSUNARI Shigeo <herumi@nifty.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Running the command:

	inotifywait -e unmount /mnt/disk

immediately aborts with a -EINVAL return code.  This is however a valid
parameter.  This abort occurs only if unmount is the sole event
parameter.  If other event parameters are supplied, then the unmount
event wait will work.

The problem was introduced by commit 44b350fc ("inotify: Fix mask
checks").  In that commit, it states:

	The mask checks in inotify_update_existing_watch() and
	inotify_new_watch() are useless because inotify_arg_to_mask()
	sets FS_IN_IGNORED and FS_EVENT_ON_CHILD bits anyway.

But instead of removing the useless checks, it did this:

	        mask = inotify_arg_to_mask(arg);
	-       if (unlikely(!mask))
	+       if (unlikely(!(mask & IN_ALL_EVENTS)))
	                return -EINVAL;

The problem is that IN_ALL_EVENTS doesn't include IN_UNMOUNT, and other
parts of the code keep IN_UNMOUNT separate from IN_ALL_EVENTS.  So the
check should be:

	if (unlikely(!(mask & (IN_ALL_EVENTS | IN_UNMOUNT))))

But inotify_arg_to_mask(arg) always sets the IN_UNMOUNT bit in the mask
anyway, so the check is always going to pass and thus should simply be
removed.  Also note that inotify_arg_to_mask completely controls what
mask bits get set from arg, there's no way for invalid bits to get
enabled there.

Lets fix it by simply removing the useless broken checks.
Signed-off-by: NJim Somerville <Jim.Somerville@windriver.com>
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: John McCutchan <john@johnmccutchan.com>
Cc: Robert Love <rlove@rlove.org>
Cc: Eric Paris <eparis@parisplace.org>
Cc: <stable@vger.kernel.org>		[2.6.37+]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, nlmclnt_lock will break out of the for(;;) loop when
the reclaimer wakes up the blocking lock thread by setting
nlm_lck_denied_grace_period. This causes the lock request to fail
with an ENOLCK error.
The intention was always to ensure that we resend the lock request
after the grace period has expired.
Reported-by: NWangyuan Zhang <Wangyuan.Zhang@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

proc_net_remove has been replaced by remove_proc_entry.
we can remove it now.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

proc_net_fops_create has been replaced by proc_create,
we can remove it now.
Signed-off-by: NGao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

now pnfs client uses block layout, maybe we can remove
blocklayoutdriver first. if we umount later,
it can cause oops in unset_pnfs_layoutdriver.
because nfss->pnfs_curr_ld->clear_layoutdriver is invalid.

reproduce it:
 modprobe  blocklayoutdriver
 mount -t nfs4 -o minorversion=1 pnfsip:/ /mnt/
 rmmod blocklayoutdriver
 umount /mnt

then you can see following

CPU 0
Pid: 17023, comm: umount.nfs4 Tainted: GF          O 3.7.0-rc6-pnfs #1 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform
RIP: 0010:[<ffffffffa04cfe6d>]  [<ffffffffa04cfe6d>] unset_pnfs_layoutdriver+0x1d/0x70 [nfsv4]
RSP: 0018:ffff8800022d9e48  EFLAGS: 00010286
RAX: ffffffffa04a1b00 RBX: ffff88000b013800 RCX: 0000000000000001
RDX: ffffffff81ae8ee0 RSI: ffff880001ee94b8 RDI: ffff88000b013800
RBP: ffff8800022d9e58 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff880001ee9400
R13: ffff8800105978c0 R14: 00007fff25846c08 R15: 0000000001bba550
FS:  00007f45ae7f0700(0000) GS:ffff880012c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffffffffa04a1b38 CR3: 0000000002c0c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process umount.nfs4 (pid: 17023, threadinfo ffff8800022d8000, task ffff880006e48aa0)
Stack:
ffff8800105978c0 ffff88000b013800 ffff8800022d9e78 ffffffffa04cd0ce
ffff8800022d9e78 ffff88000b013800 ffff8800022d9ea8 ffffffffa04755a7
ffff8800022d9ea8 ffff880002f96400 ffff88000b013800 ffff880002f96400
Call Trace:
[<ffffffffa04cd0ce>] nfs4_destroy_server+0x1e/0x30 [nfsv4]
[<ffffffffa04755a7>] nfs_free_server+0xb7/0x150 [nfs]
[<ffffffffa047d4d5>] nfs_kill_super+0x35/0x40 [nfs]
[<ffffffff81178d35>] deactivate_locked_super+0x45/0x70
[<ffffffff8117986a>] deactivate_super+0x4a/0x70
[<ffffffff81193ee2>] mntput_no_expire+0xd2/0x130
[<ffffffff81194d62>] sys_umount+0x72/0xe0
[<ffffffff8154af59>] system_call_fastpath+0x16/0x1b
Code: 06 e1 b8 ea ff ff ff eb 9e 0f 1f 44 00 00 55 48 89 e5 53 48 83 ec 08 66 66 66 66 90 48 8b 87 80 03 00 00 48 89 fb 48 85 c0 74 29 <48> 8b 40 38 48 85 c0 74 02 ff d0 48 8b 03 3e ff 48 04 0f 94 c2
RIP  [<ffffffffa04cfe6d>] unset_pnfs_layoutdriver+0x1d/0x70 [nfsv4]
RSP <ffff8800022d9e48>
CR2: ffffffffa04a1b38
---[ end trace 29f75aaedda058bf ]---

Signed-off-by: fanchaoting<fanchaoting@cn.fujitsu.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

smatch analysis:

fs/nfs/getroot.c:130 nfs_get_root() info: redundant null
 check on name calling kfree()

fs/nfs/unlink.c:272 nfs_async_unlink() info: redundant null
 check on devname_garbage calling kfree()

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: NTim Gardner <tim.gardner@canonical.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

layoutget's prepare hook can call rpc_exit with status = NFS4_OK (0).
Because of this, nfs4_proc_layoutget can't depend on a 0 status to mean
that the RPC was successfully sent, received and parsed.

To fix this, use the result's len member to see if parsing took place.

This fixes the following OOPS -- calling xdr_init_decode() with a buffer length
0 doesn't set the stream's 'p' member and ends up using uninitialized memory
in filelayout_decode_layout.

BUG: unable to handle kernel paging request at 0000000000008050
IP: [<ffffffff81282e78>] memcpy+0x18/0x120
PGD 0
Oops: 0000 [#1] SMP
last sysfs file: /sys/devices/pci0000:00/0000:00:11.0/0000:02:01.0/irq
CPU 1
Modules linked in: nfs_layout_nfsv41_files nfs lockd fscache auth_rpcgss nfs_acl autofs4 sunrpc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables ipv6 dm_mirror dm_region_hash dm_log dm_mod ppdev parport_pc parport snd_ens1371 snd_rawmidi snd_ac97_codec ac97_bus snd_seq snd_seq_device snd_pcm snd_timer snd soundcore snd_page_alloc e1000 microcode vmware_balloon i2c_piix4 i2c_core sg shpchp ext4 mbcache jbd2 sr_mod cdrom sd_mod crc_t10dif pata_acpi ata_generic ata_piix mptspi mptscsih mptbase scsi_transport_spi [last unloaded: speedstep_lib]

Pid: 1665, comm: flush-0:22 Not tainted 2.6.32-356-test-2 #2 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform
RIP: 0010:[<ffffffff81282e78>]  [<ffffffff81282e78>] memcpy+0x18/0x120
RSP: 0018:ffff88003dfab588  EFLAGS: 00010206
RAX: ffff88003dc42000 RBX: ffff88003dfab610 RCX: 0000000000000009
RDX: 000000003f807ff0 RSI: 0000000000008050 RDI: ffff88003dc42000
RBP: ffff88003dfab5b0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000080 R12: 0000000000000024
R13: ffff88003dc42000 R14: ffff88003f808030 R15: ffff88003dfab6a0
FS:  0000000000000000(0000) GS:ffff880003420000(0000) knlGS:0000000000000000
CS:  0010 DS: 0018 ES: 0018 CR0: 000000008005003b
CR2: 0000000000008050 CR3: 000000003bc92000 CR4: 00000000001407e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process flush-0:22 (pid: 1665, threadinfo ffff88003dfaa000, task ffff880037f77540)
Stack:
ffffffffa0398ac1 ffff8800397c5940 ffff88003dfab610 ffff88003dfab6a0
<d> ffff88003dfab5d0 ffff88003dfab680 ffffffffa01c150b ffffea0000d82e70
<d> 000000508116713b 0000000000000000 0000000000000000 0000000000000000
Call Trace:
[<ffffffffa0398ac1>] ? xdr_inline_decode+0xb1/0x120 [sunrpc]
[<ffffffffa01c150b>] filelayout_decode_layout+0xeb/0x350 [nfs_layout_nfsv41_files]
[<ffffffffa01c17fc>] filelayout_alloc_lseg+0x8c/0x3c0 [nfs_layout_nfsv41_files]
[<ffffffff8150e6ce>] ? __wait_on_bit+0x7e/0x90
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

When we are converting local data to an extent format as a result of
adding an attribute, the type of data contained in the local fork
determines the behaviour that needs to occur.

xfs_bmap_add_attrfork_local() already handles the directory data
case specially by using S_ISDIR() and calling out to
xfs_dir2_sf_to_block(), but with verifiers we now need to handle
each different type of metadata specially and different metadata
formats require different verifiers (and eventually block header
initialisation).

There is only a single place that we add and attribute fork to
the inode, but that is in the attribute code and it knows nothing
about the specific contents of the data fork. It is only the case of
local data that is the issue here, so adding code to hadnle this
case in the attribute specific code is wrong. Hence we are really
stuck trying to detect the data fork contents in
xfs_bmap_add_attrfork_local() and performing the correct callout
there.

Luckily the current cases can be determined by S_IS* macros, and we
can push the work off to data specific callouts, but each of those
callouts does a lot of work in common with
xfs_bmap_local_to_extents(). The only reason that this fails for
symlinks right now is is that xfs_bmap_local_to_extents() assumes
the data fork contains extent data, and so attaches a a bmap extent
data verifier to the buffer and simply copies the data fork
information straight into it.

To fix this, allow us to pass a "formatting" callback into
xfs_bmap_local_to_extents() which is responsible for setting the
buffer type, initialising it and copying the data fork contents over
to the new buffer. This allows callers to specify how they want to
format the new buffer (which is necessary for the upcoming CRC
enabled metadata blocks) and hence make xfs_bmap_local_to_extents()
useful for any type of data fork content.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: Mark Tinguely <tinguely@sgi.com> 
Signed-off-by: NBen Myers <bpm@sgi.com>

The trylock log force invoked via xfs_buf_item_push() can attempt
to acquire xa_lock, thus leading to a recursion bug when called
with xa_lock held.

This log force was originally added to xfs_buf_trylock() to address
xfsaild stalls due to pinned and stale buffers. Since the addition
of this behavior, the log item pushing code had been reworked to
detect and track pinned items to inform xfsaild to issue a log
force itself when necessary. As such, the log force on trylock
failure is redundant and safe to remove.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

The buffer pinned check and trylock sequence in xfs_buf_item_push()
can race with an active transaction on marking the buffer pinned.
This can result in the buffer becoming pinned and stale after the
initial check and the trylock failure, but before the check in
xfs_buf_trylock() that issues a log force. If the log force is
issued from this context, a spinlock recursion occurs on xa_lock.

Prepare xfs_buf_item_push() to handle the race by detecting a
pinned buffer after the trylock failure so xfsaild issues a log
force from a safe context. This, along with various previous fixes,
renders the log force in xfs_buf_trylock() redundant.
Signed-off-by: NBrian Foster <bfoster@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

Speculative preallocation based on the current file size works well
for contiguous files, but is sub-optimal for sparse files where the
EOF preallocation can fill holes and result in large amounts of
zeros being written when it is not necessary.

The algorithm is modified to prevent EOF speculative preallocation
from triggering larger allocations on IO patterns of
truncate--to-zero-seek-write-seek-write-....  which results in
non-sparse files for large files. This, unfortunately, is the way cp
now behaves when copying sparse files and so needs to be fixed.

What this code does is that it looks at the existing extent adjacent
to the current EOF and if it determines that it is a hole we disable
speculative preallocation altogether. To avoid the next write from
doing a large prealloc, it takes the size of subsequent
preallocations from the current size of the existing EOF extent.
IOWs, if you leave a hole in the file, it resets preallocation
behaviour to the same as if it was a zero size file.

Example new behaviour:

$ xfs_io -f -c "pwrite 0 31m" \
            -c "pwrite 33m 1m" \
            -c "pwrite 128m 1m" \
            -c "fiemap -v" /mnt/scratch/blah
wrote 32505856/32505856 bytes at offset 0
31 MiB, 7936 ops; 0.0000 sec (1.608 GiB/sec and 421432.7439 ops/sec)
wrote 1048576/1048576 bytes at offset 34603008
1 MiB, 256 ops; 0.0000 sec (1.462 GiB/sec and 383233.5329 ops/sec)
wrote 1048576/1048576 bytes at offset 134217728
1 MiB, 256 ops; 0.0000 sec (1.719 GiB/sec and 450704.2254 ops/sec)
/mnt/scratch/blah:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..65535]:      96..65631        65536   0x0
   1: [65536..67583]:  hole              2048
   2: [67584..69631]:  67680..69727      2048   0x0
   3: [69632..262143]: hole             192512
   4: [262144..264191]: 262240..264287    2048   0x1
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Reviewed-by: NBrian Foster <bfoster@redhat.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

The current code in pnfs_destroy_all_layouts() assumes that removing
the layout from the server->layouts list is sufficient to make it
invisible to other processes. This ignores the fact that most
users access the layout through the nfs_inode->layout...
There is further breakage due to lack of reference counting of the
layouts, meaning that the whole thing Oopses at the drop of a hat.

The code in initiate_bulk_draining() is almost correct, and can be
used as a model for pnfs_destroy_all_layouts(), so move that
code to pnfs.c, and refactor the code to allow us to choose between
a single filesystem bulk recall, and a recall of all layouts.
Also note that initiate_bulk_draining() currently calls iput() while
holding locks. Fix that too.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

This patch reinstates the ack system which withdraw should be using. It
appears to have been accidentally forgotten when the lock module was
merged into GFS2, due to two different sysfs files having the same name.
Reported-by: NDavid Teigland <teigland@redhat.com>
Signed-off-by: NSteven Whitehouse <swhiteho@redhat.com>

Using /dev/pstore as a mount point for the pstore filesystem is slightly
awkward.  We don't normally mount filesystems in /dev/ and the /dev/pstore
file isn't created automatically by anything.  While this method will
still work, we can create a persistent mount point in sysfs.  This will
put pstore on par with things like cgroups and efivarfs.
Signed-off-by: NJosh Boyer <jwboyer@redhat.com>
Acked-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Ensure that if nfs_wait_on_sequence() causes our rpc task to wait for
an NFSv4 state serialisation lock, then we also drop the session slot.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

If the server reboots after it has replied to our OPEN, but before we
call nfs4_opendata_to_nfs4_state(), then the reboot recovery thread
will not see a stateid for this open, and so will fail to recover it.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a mutex to the struct nfs4_state_owner to ensure that delegation
recall doesn't conflict with byte range lock removal.

Note that we nest the new mutex _outside_ the state manager reclaim
protection (nfsi->rwsem) in order to avoid deadlocks.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Adjust the return values so that they return EAGAIN to the caller in
cases where we might want to retry the delegation recall after
the state recovery has run.
Note that we can't wait and retry in this routine, because the caller
may be the state manager thread.

If delegation recall fails due to a session or reboot related issue,
also ensure that we mark the stateid as delegated so that
nfs_delegation_claim_opens can find it again later.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the server reboots while we are converting a delegation into
OPEN/LOCK stateids as part of a delegation return, the current code
will simply exit with an error. This causes us to lose both
delegation state and locking state (i.e. locking atomicity).

Deal with this by exposing the delegation stateid during delegation
return, so that we can recover the delegation, and then resume
open/lock recovery.

Note that not having to hold the nfs_inode->rwsem across the
calls to nfs_delegation_claim_opens() also fixes a deadlock against
the NFSv4.1 reboot recovery code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We currently have a deadlock in which the state recovery thread
ends up blocking due to one of the locks which it is trying to
recover holding the nfs_inode->rwsem.
The situation is as follows: the state recovery thread is
scheduled in order to recover from a reboot. It immediately
drains the session, forcing all ordinary NFSv4.1 calls to
nfs41_setup_sequence() to be put to sleep.  This includes the
file locking process that holds the nfs_inode->rwsem.
When the thread gets to nfs4_reclaim_locks(), it tries to
grab a write lock on nfs_inode->rwsem, and boom...

Fix is to have the lock drop the nfs_inode->rwsem while it is
doing RPC calls. We use a sequence lock in order to signal to
the locking process whether or not a state recovery thread has
run on that inode, in which case it should retry the lock.
Reported-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch adds a seqcount_t lock for use by the state manager to
signal that an open owner has been recovered. This mechanism will be
used by the delegation, open and byte range lock code in order to
figure out if they need to replay requests due to collisions with
lock recovery.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Return EEXISTS if requested file already exists, without this patch open
call will always succeed even if the file exists and user specified
O_CREAT|O_EXCL.

Following test code can be used to verify this patch. Without this patch
executing following test code on 9p mount will result in printing 'test case
failed' always.

main()
{
        int fd;

        /* first create the file */
        fd = open("./file", O_CREAT|O_WRONLY);
        if (fd < 0) {
                perror("open");
                return -1;
        }
        close(fd);

        /* Now opening same file with O_CREAT|O_EXCL should fail */
        fd = open("./file", O_CREAT|O_EXCL);
        if (fd < 0 && errno == EEXIST)
	        printf("test case pass\n");
        else
	        printf("test case failed\n");
        close(fd);
        return 0;
}
Signed-off-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

We do the truncate via setattr request, hence don't pass the O_TRUNC flag in
open request. Without this patch we end up sending zero sized write request
to server when we try to truncate. Some servers (VirtFS) were not handling that
properly.
Reported-by: NM. Mohan Kumar <mohan@in.ibm.com>
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

	... is really excessive.  First of all, ->readdir() is serialized by
file->f_path.dentry->d_inode->i_mutex; playing with file->f_path.dentry->d_lock
is not buying you anything.  Moreover, rdir->mutex is pointless for exactly
the same reason - you'll never see contention on it.

	While we are at it, there's no point in having rdir->buf a pointer -
you have it point just past the end of rdir, so it might as well be a flex
array (and no, it's not a gccism).

	Absolutely untested patch follows:
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>

Move rt scheduler definitions out of include/linux/sched.h into
new file include/linux/sched/rt.h
Signed-off-by: NClark Williams <williams@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20130207094707.7b9f825f@riff.lanSigned-off-by: NIngo Molnar <mingo@kernel.org>

In xfs_ifunlock() there is a call to wake_up_bit() after clearing
the flush lock on the xfs inode.  This is not guaranteed to be safe,
as noted in the comments above wake_up_bit() beginning with:

    In order for this to function properly, as it uses
    waitqueue_active() internally, some kind of memory
    barrier must be done prior to calling this.
Signed-off-by: NAlex Elder <elder@inktank.com>
Reviewed-by: NDave Chinner <david@fromorbit.com>
Signed-off-by: NBen Myers <bpm@sgi.com>

For some filesystems (e.g. GlusterFS), the cost of performing a
normal readdir and readdirplus are identical.  Since adaptively
using readdirplus has no benefit for those systems, give
users/filesystems the option to control adaptive readdirplus use.

v2 of this patch incorporates Miklos's suggestion to simplify the code,
as well as improving consistency of macro names and documentation.
Signed-off-by: NEric Wong <normalperson@yhbt.net>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>

Dave Sterba triggered a lockdep complaint about lock ordering
between the sb_internal lock and the cleaner semaphore.

btrfs_lookup_dentry() checks for orphans if we're looking up
the inode for a subvolume, and subvolume creation is triggering
the lookup with a transaction running.

This commit moves the d_instantiate after the transaction closes.
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

When btrfs_qgroup_reserve returned a failure, we were missing a counter
operation for BTRFS_I(inode)->outstanding_extents++, leading to warning
messages about outstanding extents and space_info->bytes_may_use != 0.
Additionally, the error handling code didn't take into account that we
dropped the inode lock which might require more cleanup.

Luckily, all the cleanup code we need is already there and can be shared
with reserve_metadata_bytes, which is exactly what this patch does.
Reported-by: NLev Vainblat <lev@zadarastorage.com>
Signed-off-by: NJan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: NChris Mason <chris.mason@fusionio.com>

We specifically do not update the disk i_size if there are ordered extents
outstanding for any area between the current disk_i_size and our ordered
extent so that we do not expose stale data.  The problem is the check we
have only checks if the ordered extent starts at or after the current
disk_i_size, which doesn't take into account an ordered extent that starts
before the current disk_i_size and ends past the disk_i_size.  Fix this by
checking if the extent ends past the disk_i_size.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

If we have an ordered extent before the ordered extent we are currently
completing that is after the current disk_i_size we will put our i_size
update into that ordered extent so that we do not expose stale data.  The
problem is that if our disk i_size is updated past the previous ordered
extent we won't update the i_size with the pending i_size update.  So check
the pending i_size update and if its above the current disk i_size we need
to go ahead and try to update.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

While running snapshot testscript created by Mitch and David,
the race between autodefrag and snapshot deletion can lead to
corruption of dead_root list so that we can get crash on
btrfs_clean_old_snapshots().

And besides autodefrag, scrub also does the same thing, ie. read
root first and get inode.

Here is the story(take autodefrag as an example):
(1) when we delete a snapshot or subvolume, it will set its root's
refs to zero and do a iput() on its own inode, and if this inode happens
to be the only active in-meory one in root's inode rbtree, it will add
itself to the global dead_roots list for later cleanup.

(2) after (1), the autodefrag thread may read another inode for defrag
and the inode is just in the deleted snapshot/subvolume, but all of these
are without checking if the root is still valid(refs > 0).  So the end up
result is adding the deleted snapshot/subvolume's root to the global
dead_roots list AGAIN.

Fortunately, we already have a srcu lock to avoid the race, ie. subvol_srcu.

So all we need to do is to take the lock to protect 'read root and get inode',
since we synchronize to wait for the rcu grace period before adding something
to the global dead_roots list.
Reported-by: NMitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

When we fail to start a transaction, we need to release the reserved free space
and qgroup space, fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Reviewed-by: NJan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

If the checks at the beginning of btrfs_file_aio_write() fail, we needn't
decrease ->sync_writers, because we have not increased it. Fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

You can run into this problem where if somebody is fsyncing and writing out
the existing extents you will have removed the extent map from the em tree,
but it's still valid for the current fsync so we go ahead and write it.  The
problem is we unconditionally try to merge it back into the em tree, but if
we've removed it from the em tree that will cause use after free problems.
Fix this to only merge if we are still a part of the tree.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fusionio.com>

There exists a situation when GC can work in background alone without
any other filesystem activity during significant time.

The nilfs_clean_segments() method calls nilfs_segctor_construct() that
updates superblocks in the case of NILFS_SC_SUPER_ROOT and
THE_NILFS_DISCONTINUED flags are set.  But when GC is working alone the
nilfs_clean_segments() is called with unset THE_NILFS_DISCONTINUED flag.
As a result, the update of superblocks doesn't occurred all this time
and in the case of SPOR superblocks keep very old values of last super
root placement.

SYMPTOMS:

Trying to mount a NILFS2 volume after SPOR in such environment ends with
very long mounting time (it can achieve about several hours in some
cases).

REPRODUCING PATH:

1. It needs to use external USB HDD, disable automount and doesn't
   make any additional filesystem activity on the NILFS2 volume.

2. Generate temporary file with size about 100 - 500 GB (for example,
   dd if=/dev/zero of=<file_name> bs=1073741824 count=200).  The size of
   file defines duration of GC working.

3. Then it needs to delete file.

4. Start GC manually by means of command "nilfs-clean -p 0".  When you
   start GC by means of such way then, at the end, superblocks is updated
   by once.  So, for simulation of SPOR, it needs to wait sometime (15 -
   40 minutes) and simply switch off USB HDD manually.

5. Switch on USB HDD again and try to mount NILFS2 volume.  As a
   result, NILFS2 volume will mount during very long time.

REPRODUCIBILITY: 100%

FIX:

This patch adds checking that superblocks need to update and set
THE_NILFS_DISCONTINUED flag before nilfs_clean_segments() call.
Reported-by: NSergey Alexandrov <splavgm@gmail.com>
Signed-off-by: NVyacheslav Dubeyko <slava@dubeyko.com>
Tested-by: NVyacheslav Dubeyko <slava@dubeyko.com>
Acked-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: NRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Return EINVAL from write if the size is larger than
allowed.  Do this before allocating kernel memory for
the bogus size, which could lead to OOM.
Reported-by: NSasha Levin <levinsasha928@gmail.com>
Tested-by: NJana Saout <jana@saout.de>
Signed-off-by: NDavid Teigland <teigland@redhat.com>