Commit Graph

3831 Commits

Author SHA1 Message Date
Anna Schumaker
7b320382d0 NFS: Rename idmap.c to nfs4idmap.c
I added the nfs4 prefix to make it obvious that this file is built into
the NFS v4 module, and not the generic client.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:16:14 -04:00
Anna Schumaker
40c64c26a4 NFS: Move nfs_idmap.h into fs/nfs/
This file is only used internally to the NFS v4 module, so it doesn't
need to be in the global include path.  I also renamed it from
nfs_idmap.h to nfs4idmap.h to emphasize that it's an NFSv4-only include
file.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:16:14 -04:00
Anna Schumaker
f9ebd61855 NFS: Remove CONFIG_NFS_V4 checks from nfs_idmap.h
The idmapper is completely internal to the NFS v4 module, so this macro
will always evaluate to true.  This patch also removes unnecessary
includes of this file from the generic NFS client.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:16:13 -04:00
Anna Schumaker
7c61f0d389 NFS: Add a stub for GETDEVICELIST
d4b18c3e (pnfs: remove GETDEVICELIST implementation) removed the
GETDEVICELIST operation from the NFS client, but left a "hole" in the
nfs4_procedures array.  This caused /proc/self/mountstats to report an
operation named "51" where GETDEVICELIST used to be.  This patch adds a
stub to fix mountstats.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Fixes: d4b18c3e (pnfs: remove GETDEVICELIST implementation)
Cc: stable@vger.kernel.org # 3.17+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:16:13 -04:00
Peng Tao
05f54903d9 nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes
For flexfiles driver, we might choose to read from mirror index other
than 0 while mirror_count is always 1 for read.

Reported-by: Jean Spector <jean@primarydata.com>
Cc: <stable@vger.kernel.org> # v3.19+
Cc: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:05:19 -04:00
Peng Tao
1ccbad9f9f nfs: fix DIO good bytes calculation
For direct read that has IO size larger than rsize, we'll split
it into several READ requests and nfs_direct_good_bytes() would
count completed bytes incorrectly by eating last zero count reply.

Fix it by handling mirror and non-mirror cases differently such that
we only count mirrored writes differently.

This fixes 5fadeb47("nfs: count DIO good bytes correctly with mirroring").

Reported-by: Jean Spector <jean@primarydata.com>
Cc: <stable@vger.kernel.org> # v3.19+
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 15:05:18 -04:00
Anna Schumaker
ea96d1ecbe nfs: Fetch MOUNTED_ON_FILEID when updating an inode
2ef47eb1 (NFS: Fix use of nfs_attr_use_mounted_on_fileid()) was a good
start to fixing a circular directory structure warning for NFS v4
"junctioned" mountpoints.  Unfortunately, further testing continued to
generate this error.

My server is configured like this:

anna@nfsd ~ % df
Filesystem      Size  Used Avail Use% Mounted on
/dev/vda1       9.1G  2.0G  6.5G  24% /
/dev/vdc1      1014M   33M  982M   4% /exports
/dev/vdc2      1014M   33M  982M   4% /exports/vol1
/dev/vdc3      1014M   33M  982M   4% /exports/vol1/vol2

anna@nfsd ~ % cat /etc/exports
/exports/          *(rw,async,no_subtree_check,no_root_squash)
/exports/vol1/     *(rw,async,no_subtree_check,no_root_squash)
/exports/vol1/vol2 *(rw,async,no_subtree_check,no_root_squash)

I've been running chown across the entire mountpoint twice in a row to
hit this problem.  The first run succeeds, but the second one fails with
the circular directory warning along with:

anna@client ~ % dmesg
[Apr 3 14:28] NFS: server 192.168.100.204 error: fileid changed
              fsid 0:39: expected fileid 0x100080, got 0x80

WHere 0x80 is the mountpoint's fileid and 0x100080 is the mounted-on
fileid.

This patch fixes the issue by requesting an updated mounted-on fileid
from the server during nfs_update_inode(), and then checking that the
fileid stored in the nfs_inode matches either the fileid or mounted-on
fileid returned by the server.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 14:43:54 -04:00
Jeff Layton
5d05e54af3 nfs: fix high load average due to callback thread sleeping
Chuck pointed out a problem that crept in with commit 6ffa30d3f7 (nfs:
don't call blocking operations while !TASK_RUNNING). Linux counts tasks
in uninterruptible sleep against the load average, so this caused the
system's load average to be pinned at at least 1 when there was a
NFSv4.1+ mount active.

Not a huge problem, but it's probably worth fixing before we get too
many complaints about it. This patch converts the code back to use
TASK_INTERRUPTIBLE sleep, simply has it flush any signals on each loop
iteration. In practice no one should really be signalling this thread at
all, so I think this is reasonably safe.

With this change, there's also no need to game the hung task watchdog so
we can also convert the schedule_timeout call back to a normal schedule.

Cc: <stable@vger.kernel.org>
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: commit 6ffa30d3f7 (“nfs: don't call blocking . . .”)
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 14:38:07 -04:00
Anna Schumaker
f830f7ddd9 NFS: Reduce time spent holding the i_mutex during fallocate()
At the very least, we should not be taking the i_mutex until after
checking if the server even supports ALLOCATE or DEALLOCATE, allowing
v4.0 or v4.1 to exit without potentially waiting on a lock.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 14:36:28 -04:00
Anna Schumaker
9a51940bf6 NFS: Don't zap caches on fallocate()
This patch adds a GETATTR to the end of ALLOCATE and DEALLOCATE
operations so we can set the updated inode size and change attribute
directly.  DEALLOCATE will still need to release pagecache pages, so
nfs42_proc_deallocate() now calls truncate_pagecache_range() before
contacting the server.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-04-23 14:36:28 -04:00
Trond Myklebust
8c18d76bcb NFS: Block new writes while syncing data in nfs_getattr()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:39 -04:00
Trond Myklebust
5bb89b4702 NFSv4.1/pnfs: Separate out metadata and data consistency for pNFS
The LAYOUTCOMMIT operation means different things to different layout types.
For blocks and objects, it is both a data and metadata consistency operation.
For files and flexfiles, it is only a metadata consistency operation.

This patch separates out the 2 cases, allowing the files/flexfiles layout
drivers to optimise away the data consistency calls to layoutcommit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:38 -04:00
Trond Myklebust
7140171ea9 NFSv4.1/pnfs: Ensure we send layoutcommit before return-on-close
We must not send a close or delegreturn that would result in a
return-on-close of the layout without ensuring that we've also
sent the necessary layoutcommit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:38 -04:00
Trond Myklebust
a0815d556d NFSv4.1/pnfs: Ensure that writes respect the O_SYNC flag when doing O_DIRECT
If the caller does not specify the O_SYNC flag, then it is legitimate
to return from O_DIRECT without doing a pNFS layoutcommit operation.
However if the file is opened O_DIRECT|O_SYNC then we'd better get it
right.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:37 -04:00
Trond Myklebust
9e1681c2e7 NFSv4: Truncating file opens should also sync O_DIRECT writes
We don't just want to sync out buffered writes, but also O_DIRECT ones.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:37 -04:00
Trond Myklebust
d9dabc1a01 NFS: File unlock needs to be a metadata synchronisation point
File unlock needs to update both data and metadata on the NFS server
in order to act as a synchronisation point for other clients.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:37 -04:00
Trond Myklebust
4d346bea8f NFS: Add a helper to sync both O_DIRECT and buffered writes
Then apply it to nfs_setattr() and nfs_getattr().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:36 -04:00
Trond Myklebust
67af7611ec NFSv4.1/pnfs: Refactor pnfs_set_layoutcommit()
pnfs_set_layoutcommit() and pnfs_commit_set_layoutcommit() are 100% identical
except for the function arguments. Refactor to eliminate the difference.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:36 -04:00
Trond Myklebust
29559b11ae NFSv4.1/pnfs: Fix setting of layoutcommit last write byte
If the NFS_INO_LAYOUTCOMMIT flag was unset, then we _must_ ensure that
we also reset the last write byte (lwb) for that layout. The current
code depends on us clearing the lwb when we clear NFS_INO_LAYOUTCOMMIT,
which is not the case when we call pnfs_clear_layoutcommit().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:35 -04:00
Trond Myklebust
415320fc14 NFSv4: Return the delegation before returning the layout in evict_inode()
Minor optimisation for the case where the layout has return-on-close
enabled.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:35 -04:00
Trond Myklebust
81b79afb50 NFSv4: Allow tracing of NFSv4 fsync calls
I appear to have missed this when adding the ftrace probes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:39:34 -04:00
Trond Myklebust
fc87701b91 NFS: Fix free_deveiceid -> free_deviceid
Make it easier to grep for these functions by name.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:32:24 -04:00
Trond Myklebust
df52699e4f NFSv4.1: Don't cache deviceids that have no notifications
The spec says that once all layouts that reference a given deviceid
have been returned, then we are only allowed to continue to cache
the deviceid if the metadata server supports notifications.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:32:24 -04:00
Trond Myklebust
4e59080397 NFSv4.1: Allow getdeviceinfo to return notification info back to caller
We are only allowed to cache deviceinfo if the server supports notifications
and actually promises to call us back when changes occur. Right now, we
request those notifications, but then we don't check the server's reply.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:32:24 -04:00
Trond Myklebust
fb1458f457 NFSv4.1: Cleanup - don't opencode nfs4_put_deviceid_node()
There really is no reason to do so.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:32:24 -04:00
Trond Myklebust
84a80f62f7 NFSv4.1: Convert pNFS deviceid to use kfree_rcu()
Use of synchronize_rcu() when unmounting and potentially freeing a lot
of deviceids is problematic. There really is no reason why we can't just
use kfree_rcu() here.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-27 12:32:24 -04:00
Peng Tao
2854475f6c nfs: clean up nfs_direct_IO
This follows up "nfs: fix dio deadlock when O_DIRECT flag is flipped"
and removes the unnecessary CONFIG_NFS_SWAP switch.

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-13 09:05:25 -04:00
Trond Myklebust
38942ba204 NFSv4: Append delegations to the per-client list instead of prepending
Do so on the assumption that for most use cases, that list will turn into
a more or less LRU-ordered list, and so the list traversals in
nfs_client_return_marked_delegations() are likely to be shorter before
hitting a candidate to return.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-12 12:13:56 -04:00
Trond Myklebust
e11259f920 NFSv4.1: Clear the old state by our client id before establishing a new lease
If the call to exchange-id returns with the EXCHGID4_FLAG_CONFIRMED_R flag
set, then that means our lease was established by a previous mount instance.
Ensure that we detect this situation, and that we clear the state held by
that mount.

Reported-by: Jorge Mora <Jorge.Mora@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 21:52:30 -05:00
Trond Myklebust
48d66b9749 NFSv4: Fix a race in NFSv4.1 server trunking discovery
We do not want to allow a race with another NFS mount to cause
nfs41_walk_client_list() to establish a lease on our nfs_client before
we're done checking for trunking.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 20:42:23 -05:00
Trond Myklebust
ef070dcb39 NFS: Don't write enable new pages while an invalidation is proceeding
nfs_vm_page_mkwrite() should wait until the page cache invalidation
is finished. This is the second patch in a 2 patch series to deprecate
the NFS client's reliance on nfs_release_page() in the context of
nfs_invalidate_mapping().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 13:58:08 -05:00
Trond Myklebust
874f946376 NFS: Fix a regression in the read() syscall
When invalidating the page cache for a regular file, we want to first
sync all dirty data to disk and then call invalidate_inode_pages2().
The latter relies on nfs_launder_page() and nfs_release_page() to deal
respectively with dirty pages, and unstable written pages.

When commit 9590544694 ("NFS: avoid deadlocks with loop-back mounted
NFS filesystems.") changed the behaviour of nfs_release_page(), then it
made it possible for invalidate_inode_pages2() to fail with an EBUSY.
Unfortunately, that error is then propagated back to read().

Let's therefore work around the problem for now by protecting the call
to sync the data and invalidate_inode_pages2() so that they are atomic
w.r.t. the addition of new writes.
Later on, we can revisit whether or not we still need nfs_launder_page()
and nfs_release_page().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-03 13:02:29 -05:00
Trond Myklebust
ec3ca4e57e NFSv4: Ensure we skip delegations that are already being returned
In nfs_client_return_marked_delegations() and nfs_delegation_reap_unclaimed()
we want to optimise the loop traversal by skipping delegations that are
already in the process of being returned.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-02 18:09:15 -05:00
Trond Myklebust
9f0f8e12c4 NFSv4: Pin the superblock while we're returning the delegation
This patch ensures that the superblock doesn't go ahead and disappear
underneath us while the state manager thread is returning delegations.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-02 18:09:14 -05:00
Trond Myklebust
ade04647dd NFSv4: Ensure we honour NFS_DELEGATION_RETURNING in nfs_inode_set_delegation()
Ensure that nfs_inode_set_delegation() doesn't inadvertently detach a
delegation that is already in the process of being returned.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-02 18:09:14 -05:00
Trond Myklebust
b04b22f4ca NFSv4: Ensure that we don't reap a delegation that is being returned
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-02 18:09:13 -05:00
Anna Schumaker
369d6b7f00 NFS: Fix stateid used for NFS v4 closes
After 566fcec60 the client uses the "current stateid" from the
nfs4_state structure to close a file.  This could potentially contain a
delegation stateid, which is disallowed by the protocol and causes
servers to return NFS4ERR_BAD_STATEID.  This patch restores the
(correct) behavior of sending the open stateid to close a file.

Reported-by: Olga Kornievskaia <kolga@netapp.com>
Fixes: 566fcec60 (NFSv4: Fix an atomicity problem in CLOSE)
Signed-off-by: Anna Schumaker <Anna.Schumaker@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-02 18:06:42 -05:00
Trond Myklebust
7c0af9ffb7 NFSv4: Don't call put_rpccred() under the rcu_read_lock()
put_rpccred() can sleep.

Fixes: 8f649c3762 ("NFSv4: Fix the locking in nfs_inode_reclaim_delegation()")
Cc: stable@vger.kernel.org # 2.6.35+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-01 23:23:07 -05:00
Trond Myklebust
fa9233699c NFS: Don't require a filehandle to refresh the inode in nfs_prime_dcache()
If the server does not return a valid set of attributes that we can
use to either create a file or refresh the inode, then there is no
value in calling nfs_prime_dcache().

However if we're just refreshing the inode using the attributes that
the server returned, then it shouldn't matter whether or not we have
a filehandle, as long as we check the fsid+fileid combination.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-01 23:23:07 -05:00
Trond Myklebust
1ae04b2523 NFSv3: Use the readdir fileid as the mounted-on-fileid
When we call readdirplus, set the fileid normally returned by readdir
as the mounted-on-fileid, since that is commonly the case if there is
a mountpoint. To ensure that we get it right, we only set the flag if
the readdir fileid differs from the one returned in the readdirplus
attributes.

This again means that we can avoid the issues described in commit
2ef47eb1ae ("NFS: Fix use of nfs_attr_use_mounted_on_fileid()"),
which only fixed NFSv4.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-01 23:23:07 -05:00
Trond Myklebust
6c441c254e NFS: Don't invalidate a submounted dentry in nfs_prime_dcache()
If we're traversing a directory which contains a submounted filesystem,
or one that has a referral, the NFS server that is processing the READDIR
request will often return information for the underlying (mounted-on)
directory. It may, or may not, also return filehandle information.

If this happens, and the lookup in nfs_prime_dcache() returns the
dentry for the submounted directory, the filehandle comparison will
fail, and we call d_invalidate(). Post-commit 8ed936b567
("vfs: Lazily remove mounts on unlinked files and directories."), this
means the entire subtree is unmounted.

The following minimal patch addresses this problem by punting on
the invalidation if there is a submount.

Kudos to Neil Brown <neilb@suse.de> for having tracked down this
issue (see link).

Reported-by: Nix <nix@esperi.org.uk>
Link: http://lkml.kernel.org/r/87iofju9ht.fsf@spindle.srvr.nix
Cc: stable@vger.kernel.org # 3.18+
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
3235b40303 NFSv4: Set a barrier in the update_changeattr() helper
Ensure that we don't regress the changes that were made to the
directory.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
92d64e47b6 NFS: Fix nfs_post_op_update_inode() to set an attribute barrier
nfs_post_op_update_inode() is called after a self-induced attribute
update. Ensure that it also sets the barrier.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
00fb4c9f84 NFS: Remove size hack in nfs_inode_attrs_need_update()
Prior to this patch, we used to always OK attribute updates that extended
the file size on the assumption that we might be performing writeback.
Now that we have attribute barriers to protect the writeback related updates,
we should remove this hack, as it can cause truncate() operations to
apparently be reverted if/when a readahead or getattr RPC call races
with our on-the-wire SETATTR.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
8f8ba1d739 NFSv4: Add attribute update barriers to delegreturn and pNFS layoutcommit
Ensure that other operations that race with delegreturn and layoutcommit
cannot revert the attribute updates that were made on the server.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
a08a8cd375 NFS: Add attribute update barriers to NFS writebacks
Ensure that other operations that race with our write RPC calls
cannot revert the file size updates that were made on the server.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
f506200346 NFS: Set an attribute barrier on all updates
Ensure that we update the attribute barrier even if there were no
invalidations, provided that this value is newer than the old one.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:06 -05:00
Trond Myklebust
f044636d97 NFS: Add attribute update barriers to nfs_setattr_update_inode()
Ensure that other operations which raced with our setattr RPC call
cannot revert the file attribute changes that were made on the server.
To do so, we artificially bump the attribute generation counter on
the inode so that all calls to nfs_fattr_init() that precede ours
will be dropped.

The motivation for the patch came from Chuck Lever's reports of readaheads
racing with truncate operations and causing the file size to be reverted.

Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:05 -05:00
Trond Myklebust
140e049c64 NFS: Add a helper to set attribute barriers
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:23:05 -05:00
Trond Myklebust
aa5accea40 NFS: Ensure that buffered writes wait for O_DIRECT writes to complete
The O_DIRECT code will grab the inode->i_mutex and flush out buffered
writes, before scheduling a read or a write. However there is no
equivalent in the buffered write code to wait for O_DIRECT to complete.

Fixes a reported issue in xfstests generic/133, when first performing an
O_DIRECT write followed by a buffered write.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
2015-03-01 23:22:40 -05:00