Commit Graph

182 Commits

Author SHA1 Message Date
Trond Myklebust
f41f741838 NFS: Ensure we zap only the access and acl caches when setting new acls
...and ensure that we obey the NFS_INO_INVALID_ACL flag when retrieving the
acls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:19 -04:00
Trond Myklebust
659bfcd6dd NFS: Fix the ftruncate() credential problem
ftruncate() access checking is supposed to be performed at open() time,
just like reads and writes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-07-09 12:09:14 -04:00
Jan Blunck
31f31db1a1 nfs: path_{get,put}() cleanups
Here are some more places where path_{get,put}() can be used instead of
dput()/mntput() pair.

Signed-off-by: Jan Blunck <jblunck@suse.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16 09:43:30 -07:00
Harvey Harrison
3110ff8048 nfs: replace remaining __FUNCTION__ occurrences
__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16 09:43:29 -07:00
Trond Myklebust
b0b539739f NFS: Ensure that 'noac' and/or 'actimeo=0' turn off attribute caching
Both the 'noac' and 'actimeo=0' mount options should ensure that attributes
are not cached, however a bug in nfs_attribute_timeout() means that
currently, the attributes may in fact get cached for up to one jiffy. This
has been seen to cause corruption in some applications.

The reason for the bug is that the time_in_range() test returns 'true' as
long as the current time lies between nfsi->read_cache_jiffies and
nfsi->read_cache_jiffies + nfsi->attrtimeo. In other words, if jiffies
equals nfsi->read_cache_jiffies, then we still cache the attribute data.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-05-16 09:43:21 -07:00
Trond Myklebust
233607dbbc Merge branch 'devel' 2008-04-24 14:01:02 -04:00
Jeff Layton
66d3aac041 NFS: initialize flags field in nfs_open_context
The nfs_open_context struct had a "flags" field added recently, but the
allocator isn't initializing it. It also looks like the allocator isn't
initializing the mode or list either, but they seem to be overwritten
by the caller, so that's less of an issue.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-04-08 21:06:53 -04:00
Trond Myklebust
98a8e32394 SUNRPC: Add a helper rpcauth_lookup_generic_cred()
The NFSv4 protocol allows clients to negotiate security protocols on the
fly in the case where an administrator on the server changes the export
settings and/or in the case where we may have a filesystem migration event.

Instead of having the NFS client code cache credentials that are tied to a
particular AUTH method it is therefore preferable to have a generic credential
that can be converted into whatever AUTH is in use by the RPC client when
the read/write/sillyrename/... is put on the wire.

We do this by means of the new "generic" credential, which basically just
caches the minimal information that is needed to look up an RPCSEC_GSS,
AUTH_SYS, or AUTH_NULL credential.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-14 13:42:49 -04:00
Trond Myklebust
9446389ef6 Merge commit 'origin' into devel 2008-03-08 11:49:24 -05:00
Trond Myklebust
c37dcd334c NFS: Fix the fsid revalidation in nfs_update_inode()
When we detect that we've crossed a mountpoint on the remote server, we
must take care not to use that inode to revalidate the fsid on our
current superblock. To do so, we label the inode as a remote mountpoint,
and check for that in nfs_update_inode().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-03-07 14:35:37 -05:00
Trond Myklebust
5746006f1d NFS: Add an nfsiod workqueue
NFS post-rpciod cleanups often involve tasks that cannot be safely
performed within the rpciod context (due to deadlock concerns). We
therefore add a dedicated NFS workqueue that can perform tasks like
cleaning up state after an interrupted NFSv4 open() call, or calling
put_nfs_open_context() after an asynchronous read or write call.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:36 -08:00
Trond Myklebust
383ba71938 NFS: Fix a deadlock with lazy umount
We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare()
and task->tk_ops->rpc_call_done() to call mntput() in any way, since
that will cause a deadlock when the call to rpc_shutdown_client() attempts
to wait on 'task' to complete.

We can avoid the above deadlock by moving calls to mntput to
task->tk_ops->rpc_release() callback, since at that time the task will be
marked as completed, and so rpc_shutdown_client won't attempt to wait on
it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-02-25 21:40:33 -08:00
Linus Torvalds
75659ca0c1 Merge branch 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc
* 'task_killable' of git://git.kernel.org/pub/scm/linux/kernel/git/willy/misc: (22 commits)
  Remove commented-out code copied from NFS
  NFS: Switch from intr mount option to TASK_KILLABLE
  Add wait_for_completion_killable
  Add wait_event_killable
  Add schedule_timeout_killable
  Use mutex_lock_killable in vfs_readdir
  Add mutex_lock_killable
  Use lock_page_killable
  Add lock_page_killable
  Add fatal_signal_pending
  Add TASK_WAKEKILL
  exit: Use task_is_*
  signal: Use task_is_*
  sched: Use task_contributes_to_load, TASK_ALL and TASK_NORMAL
  ptrace: Use task_is_*
  power: Use task_is_*
  wait: Use TASK_NORMAL
  proc/base.c: Use task_is_*
  proc/array.c: Use TASK_REPORT
  perfmon: Use task_is_*
  ...

Fixed up conflicts in NFS/sunrpc manually..
2008-02-01 11:45:47 +11:00
Trond Myklebust
e6f8107595 NFS: Add an asynchronous delegreturn operation for use in nfs_clear_inode
Otherwise, there is a potential deadlock if the last dput() from an NFSv4
close() or other asynchronous operation leads to nfs_clear_inode calling
the synchronous delegreturn.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:06:12 -05:00
Benny Halevy
99fadcd764 nfs: convert NFS_*(inode) helpers to static inline
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:06:11 -05:00
Benny Halevy
3a10c30acc nfs: obliterate NFS_FLAGS macro
use NFS_I(inode)->flags instead

Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:06:11 -05:00
Trond Myklebust
bfc69a4566 NFS: define a function to update nfsi->cache_change_attribute
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:47 -05:00
Chuck Lever
28c494c5c8 NFS: Prevent nfs_getattr() hang during heavy write workloads
POSIX requires that ctime and mtime, as reported by the stat(2) call,
reflect the activity of the most recent write(2).  To that end, nfs_getattr()
flushes pending dirty writes to a file before doing a GETATTR to allow the
NFS server to set the file's size, ctime, and mtime properly.

However, nfs_getattr() can be starved when a constant stream of application
writes to a file prevents nfs_wb_nocommit() from completing.  This usually
results in hangs of programs doing a stat against an NFS file that is being
written.  "ls -l" is a common victim of this behavior.

To prevent starvation, hold the file's i_mutex in nfs_getattr() to
freeze applications writes temporarily so the client can more quickly obtain
clean values for a file's size, mtime, and ctime.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:45 -05:00
Chuck Lever
8a8c74bf94 NFS: Ensure nfs_wcc_update_inode always converts file size to loff_t
The nfs_wcc_update_inode() function omits logic to convert the type of
the NFS on-the-wire value of a file's size (__u64) to the type of file
size value stored in struct inode (loff_t, which is signed).

Everywhere else in the NFS client I checked already correctly converts the
file size type.

This effects only very large files.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2008-01-30 02:05:43 -05:00
Matthew Wilcox
150030b78a NFS: Switch from intr mount option to TASK_KILLABLE
By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option.  We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.

Signed-off-by: Liam R. Howlett <howlett@gmail.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
2007-12-06 17:40:25 -05:00
Trond Myklebust
a49c3c7736 NFSv4: Ensure that we wait for the CLOSE request to complete
Otherwise, we do end up breaking close-to-open semantics. We also end up
breaking some of the silly-rename tests in Connectathon on some setups.

Please refer to the bug-report at
	http://bugzilla.linux-nfs.org/show_bug.cgi?id=150

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-19 17:19:25 -04:00
Trond Myklebust
565277f63c NFS: Fix a race in sillyrename
lookup() and sillyrename() can race one another because the sillyrename()
completion cannot take the parent directory's inode->i_mutex since the
latter may be held by whoever is calling dput().

We therefore have little option but to add extra locking to ensure that
nfs_lookup() and nfs_atomic_open() do not race with the sillyrename
completion.
If somebody has looked up the sillyrenamed file in the meantime, we just
transfer the sillydelete information to the new dentry.

Please refer to the bug-report at
	http://bugzilla.linux-nfs.org/show_bug.cgi?id=150

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-19 17:19:16 -04:00
Jeff Layton
188b95dd8e NFS: if ATTR_KILL_S*ID bits are set, then skip mode change
If the ATTR_KILL_S*ID bits are set then any mode change is only for clearing
the setuid/setgid bits.  For NFS, skip the mode change and let the server
handle it.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-18 14:37:22 -07:00
Christoph Lameter
4ba9b9d0ba Slab API: remove useless ctor parameter and reorder parameters
Slab constructors currently have a flags parameter that is never used.  And
the order of the arguments is opposite to other slab functions.  The object
pointer is placed before the kmem_cache pointer.

Convert

        ctor(void *object, struct kmem_cache *s, unsigned long flags)

to

        ctor(struct kmem_cache *s, void *object)

throughout the kernel

[akpm@linux-foundation.org: coupla fixes]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:45 -07:00
Trond Myklebust
f43bf0bebe NFS: Add a boot parameter to disable 64 bit inode numbers
This boot parameter will allow legacy 32-bit applications which call stat()
to continue to function even if the NFSv3/v4 server uses 64-bit inode
numbers.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:20:52 -04:00
Trond Myklebust
2a3f5fd459 NFS: nfs_refresh_inode should clear cache_validity flags on success
If the cached attributes match the ones supplied in the fattr, then assume
we've revalidated the inode.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:20:50 -04:00
Trond Myklebust
40d2470409 NFS: Fix a connectathon regression in NFSv3 and NFSv4
We're failing basic test6 against Linux servers because they lack a correct
change attribute. The fix is to assume that we always want to invalidate
the readdir caches when we call update_changeattr and/or
nfs_post_op_update_inode on a directory.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:20:47 -04:00
Trond Myklebust
c7c209730d NFS: Get rid of some obsolete macros
- NFS_READTIME, NFS_CHANGE_ATTR are completely unused.
- Inline the few remaining uses of NFS_ATTRTIMEO, and remove.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:20:23 -04:00
Trond Myklebust
6d2b296686 NFS: Reset nfsi->last_updated only if the attribute changed
Otherwise set it to nfsi->read_cache_jiffies in order to prevent jiffy
wraparound issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:55 -04:00
Trond Myklebust
60ccd4ec41 NFS: Remove nfs_begin_data_update/nfs_end_data_update
The lower level routines in fs/nfs/proc.c, fs/nfs/nfs3proc.c and
fs/nfs/nfs4proc.c should already be dealing with the revalidation issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:53 -04:00
Trond Myklebust
80eb209def NFS: Remove NFS_I(inode)->data_updates
We have no more users...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:50 -04:00
Trond Myklebust
7668fdbe9a NFS: nfs_post_op_update_inode don't update cache_change_attribute
If nfs_post_op_update_inode fails because the server didn't return any
attributes, then we let the subsequent inode revalidation update
cache_change_attribute.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:37 -04:00
Trond Myklebust
12b373ebf0 NFS: Don't revalidate dentries on directory size or ctime changes
We only need to look at the mtime changes...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:35 -04:00
Trond Myklebust
2f78e4313a NFS: Don't set cache_change_attribute in nfs_revalidate_mapping
The attribute revalidation code will already have taken care of resetting
nfsi->cache_change_attribute.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:32 -04:00
Trond Myklebust
70ca88521f NFS: Fake up 'wcc' attributes to prevent cache invalidation after write
NFSv2 and v4 don't offer weak cache consistency attributes on WRITE calls.
In NFSv3, returning wcc data is optional. In all cases, we want to prevent
the client from invalidating our cached data whenever ->write_done()
attempts to update the inode attributes.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:15 -04:00
Trond Myklebust
b64e8a5ef7 NFS: Remove bogus check of cache_change_attribute in nfs_update_inode
Remove the bogus 'data_stable' check in nfs_update_inode. The
cache_change_attribute tells you if the directory changed on the server,
and should have nothing to do with the file length.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:11 -04:00
Trond Myklebust
7fdc49c4e4 NFS: Fix the ESTALE "revalidation" in _nfs_revalidate_inode()
For one thing, the test NFS_ATTRTIMEO() == 0 makes no sense: we're
testing whether or not the cache timeout length is zero, which is totally
unrelated to the issue of whether or not we trust the file staleness.

Secondly, we do not want to retry the GETATTR once a file has been declared
stale by the server: we rather want to discard that inode as soon as
possible, since there are broken servers still in use out there that reuse
filehandles on new files.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:08 -04:00
Trond Myklebust
c481299839 NFS: Fix atime revalidation in readdir()
NFSv3 will correctly update atime on a readdir call, so there is no need to
set the NFS_INO_INVALID_ATIME flag unless the call to nfs_refresh_inode()
fails.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:19:03 -04:00
Trond Myklebust
47aabaa7e4 NFSv4: Don't use ctime/mtime for determining when to invalidate the caches
In NFSv4 we should only be looking at the change attribute.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:57 -04:00
Trond Myklebust
17cadc9537 NFS: Don't force a dcache revalidation if nfs_wcc_update_inode succeeds
The reason is that if the weak cache consistency update was successful,
then we know that our client must be the only one that changed the
directory, and we've already updated the dcache to reflect the change.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:55 -04:00
Trond Myklebust
e323ea46d9 NFS: nfs_wcc_update_inode: directory caches are always invalidated
We must ensure that the readdir data is always invalidated whether or not
the weak cache consistency data update succeeds.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:51 -04:00
Trond Myklebust
6ecc5e8fca NFS: Fix dcache revalidation bugs
We don't need to force a dentry lookup just because we're making changes to
the directory.

Don't update nfsi->cache_change_attribute in nfs_end_data_update: that
overrides the NFSv3/v4 weak consistency checking that tells us our update
was the only one, and that tells us the dcache is still valid.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:49 -04:00
Trond Myklebust
7957c1418f NFS: fix nfs_verify_change_attribute
We always want to check that the verifier and directory
cache_change_attribute match. This also allows us to remove the 'wraparound
hack' for the cache_change_attribute. If we're only checking for equality,
then we don't care about wraparound issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:46 -04:00
Trond Myklebust
68e8a70d3c NFS: nfs_post_op_update_inode() should call nfs_refresh_inode()
Ensure that we don't clobber the results from a more recent getattr call...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:43 -04:00
Trond Myklebust
f2115dc987 NFS: Fix over-conservative attribute invalidation in nfs_update_inode()
We should always be declaring the attribute cache as valid after having
updated it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:40 -04:00
Trond Myklebust
cd3758e37d NFS: Replace file->private_data with calls to nfs_file_open_context()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:18:31 -04:00
Fabio Olive Leite
c7e1596111 Re: [NFS] [PATCH] Attribute timeout handling and wrapping u32 jiffies
I would like to discuss the idea that the current checks for attribute
timeout using time_after are inadequate for 32bit architectures, since
time_after works correctly only when the two timestamps being compared
are within 2^31 jiffies of each other. The signed overflow caused by
comparing values more than 2^31 jiffies apart will flip the result,
causing incorrect assumptions of validity.

2^31 jiffies is a fairly large period of time (~25 days) when compared
to the lifetime of most kernel data structures, but for long lived NFS
mounts that can sit idle for months (think that for some reason autofs
cannot be used), it is easy to compare inode attribute timestamps with
very disparate or even bogus values (as in when jiffies have wrapped
many times, where the comparison doesn't even make sense).

Currently the code tests for attribute timeout by simply adding the
desired amount of jiffies to the stored timestamp and comparing that
with the current timestamp of obtained attribute data with time_after.
This is incorrect, as it returns true for the desired timeout period
and another full 2^31 range of jiffies.

In testing with artificial jumps (several small jumps, not one big
crank) of the jiffies I was able to reproduce a problem found in a
server with very long lived NFS mounts, where attributes would not be
refreshed even after touching files and directories in the server:

Initial uptime:
03:42:01 up 6 min, 0 users, load average: 0.01, 0.12, 0.07

NFS volume is mounted and time is advanced:
03:38:09 up 25 days, 2 min, 0 users, load average: 1.22, 1.05, 1.08

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Dec 17 03:38 /local/A/foo/bar
-rw-r--r--  1 root root 0 Nov 22 00:36 /nfs/A/foo/bar

# touch /local/A/foo/bar

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Dec 17 03:47 /local/A/foo/bar
-rw-r--r--  1 root root 0 Nov 22 00:36 /nfs/A/foo/bar

We can see the local mtime is updated, but the NFS mount still shows
the old value. The patch below makes it work:

Initial setup...
07:11:02 up 25 days, 1 min,  0 users,  load average: 0.15, 0.03, 0.04

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:11 /local/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:11 /nfs/A/foo/bar

# touch /local/A/foo/bar

# ls -l /local/A/foo/bar /nfs/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:14 /local/A/foo/bar
-rw-r--r--  1 root root 0 Jan 11 07:14 /nfs/A/foo/bar

Signed-off-by: Fabio Olive Leite <fleite@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:33 -04:00
Peter Staubach
4e769b934e 64 bit ino support for NFS client
Hi.

Attached is a patch to modify the NFS client code to support
64 bit ino's, as appropriate for the system and the NFS
protocol version.

The code basically just expand the NFS interfaces for routines
which handle ino's from using ino_t to u64 and then uses the
fileid in the nfs_inode instead of i_ino in the inode.  The
code paths that were updated are in the getattr method and
the readdir methods.

This should be no real change on 64 bit platforms.  Since
the ino_t is an unsigned long, it would already be 64 bits
wide.

    Thanx...

           ps

Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:29 -04:00
Trond Myklebust
ed90ef51a3 NFS: Clean up NFS writeback flush code
The only user of nfs_sync_mapping_range() is nfs_getattr(), which uses it
to flush out the entire inode without sending a commit. We therefore
replace nfs_sync_mapping_range with a more appropriate helper.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-10-09 17:15:18 -04:00
Trond Myklebust
5e11934d13 NFS: Fix put_nfs_open_context
We need to grab the inode->i_lock atomically with the last reference put in
order to remove the open context that is being freed from the
nfsi->open_files list.

Fix by converting the kref to a standard atomic counter and then using
atomic_dec_and_lock()...

Thanks to Arnd Bergmann for pointing out the problem.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2007-08-07 15:13:17 -04:00