Commit Graph

75 Commits

Author SHA1 Message Date
NeilBrown
4a3ae42dc3 [PATCH] knfsd: Correctly handle error condition from lockd_up
If lockd_up fails - what should we expect?  Do we have to later call
lockd_down?

Well the nfs client thinks "no", the nfs server thinks "yes".  lockd thinks
"yes".

The only answer that really makes sense is "no" !!

So:
  Make lockd_up only increment  nlmsvc_users on success.
  Make nfsd handle errors from lockd_up properly.
  Make sure lockd_up(0) never fails when lockd is running
    so that the 'reclaimer' call to lockd_up doesn't need to
    be error checked.

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:18 -07:00
NeilBrown
7dcf91ec66 [PATCH] knfsd: Move makesock failed warning into make_socks.
Thus it is printed for any path that leads to failure (make_socks is called
from two places).

Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:18 -07:00
NeilBrown
6fb2b47fa1 [PATCH] knfsd: Drop 'serv' option to svc_recv and svc_process
It isn't needed as it is available in rqstp->rq_server, and dropping it allows
some local vars to be dropped.

[akpm@osdl.org: build fix]
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:18 -07:00
NeilBrown
24e36663c3 [PATCH] knfsd: be more selective in which sockets lockd listens on
Currently lockd listens on UDP always, and TCP if CONFIG_NFSD_TCP is set.

However as lockd performs services of the client as well, this is a problem.
If CONFIG_NfSD_TCP is not set, and a tcp mount is used, the server will not be
able to call back to lockd.

So:
 - add an option to lockd_up saying which protocol is needed
 - Always open sockets for which an explicit port was given, otherwise
   only open a socket of the type required
 - Change nfsd to do one lockd_up per socket rather than one per thread.

This
 - removes the dependancy on CONFIG_NFSD_TCP
 - means that lockd may open sockets other than at startup
 - means that lockd will *not* listen on UDP if the only
   mounts are TCP mount (and nfsd hasn't started).

The latter is the only one that concerns me at all - I don't know if this
might be a problem with some servers.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:17 -07:00
NeilBrown
bc591ccff2 [PATCH] knfsd: add a callback for when last rpc thread finishes
nfsd has some cleanup that it wants to do when the last thread exits, and
there will shortly be some more.  So collect this all into one place and
define a callback for an rpc service to call when the service is about to be
destroyed.

[akpm@osdl.org: cleanups, build fix]
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:17 -07:00
Martin Bligh
b7b52630de [PATCH] add newline to nfs dprintk
Add missing \n to dprintk

Signed-off-by: Martin Bligh <mbligh@google.com>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:19 -07:00
Panagiotis Issaris
f52720ca5f [PATCH] fs: Removing useless casts
* Removing useless casts
* Removing useless wrapper
* Conversion from kmalloc+memset to kzalloc

Signed-off-by: Panagiotis Issaris <takis@issaris.org>
Acked-by: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Panagiotis Issaris
f8314dc60c [PATCH] fs: Conversions from kmalloc+memset to k(z|c)alloc
Conversions from kmalloc+memset to kzalloc.

Signed-off-by: Panagiotis Issaris <takis@issaris.org>
Jffs2-bit-acked-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27 08:26:10 -07:00
Chuck Lever
e1ec78928b LOCKD: Convert to use new rpc_create() API
Replace xprt_create_proto/rpc_create_client with new rpc_create()
interface in the Network Lock Manager.

Note that the semantics of NLM transports is now "hard" instead of "soft"
to provide a better guarantee that lock requests will get to the server.

Test plan:
Repeated runs of Connectathon locking suite.  Check network trace to ensure
NLM requests are working correctly.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:50 -04:00
Chuck Lever
6ca9482387 SUNRPC: Clean-up after previous patches.
Remove some unused macros related to accessing an RPC peer address

Test plan:
Compile kernel with CONFIG_NFS option enabled.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:49 -04:00
Chuck Lever
44c31be261 LOCKD: Teach lockd to use the new rpc_peeraddr() API
Hide the details of how the RPC client stores remote peer addresses from
the Network Lock Manager.

Test plan:
Destructive testing (unplugging the network temporarily).  Connectathon
with UDP and TCP.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-09-22 23:24:46 -04:00
Trond Myklebust
01df9c5e91 LOCKD: Fix a deadlock in nlm_traverse_files()
nlm_traverse_files() is not allowed to hold the nlm_file_mutex while calling
nlm_inspect file, since it may end up calling nlm_release_file() when
releaseing the blocks.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from e558d3cde986e04f68afe8c790ad68ef4b94587a commit)
2006-08-24 15:51:00 -04:00
J. Bruce Fields
f3d43c769d NLM/lockd: remove b_done
We never actually set the b_done field any more; it's always zero.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from af8412d4283ef91356e65e0ed9b025b376aebded commit)
2006-08-03 16:56:02 -04:00
Trond Myklebust
01c3b861cd NLM,NFSv4: Wait on local locks before we put RPC calls on the wire
Use FL_ACCESS flag to test and/or wait for local locks before we try
requesting a lock from the server

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-07-05 13:13:18 -04:00
Trond Myklebust
9b07357490 NLM,NFSv4: Don't put UNLOCK requests on the wire unless we hold a lock
Use the new behaviour of {flock,posix}_file_lock(F_UNLCK) to determine if
we held a lock, and only send the RPC request to the server if this was the
case.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-07-05 13:13:17 -04:00
Jörn Engel
6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Trond Myklebust
28df955a2a NLM: Fix reclaim races
Currently it is possible for a task to remove its locks at the same time as
the NLM recovery thread is trying to recover them. This quickly leads to an
Oops.
Protect the locks using an rw semaphore while they are being recovered.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-09 09:40:27 -04:00
Trond Myklebust
5046791417 NLM: sem to mutex conversion
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-06-09 09:40:24 -04:00
Adrian Bunk
ec535ce154 NFS: make 2 functions static
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-04-19 12:43:47 -04:00
Ingo Molnar
353ab6e97b [PATCH] sem2mutex: fs/
Semaphore to mutex conversion.

The conversion was generated via scripts, and the result was validated
automatically via a script as well.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Eric Van Hensbergen <ericvh@ericvh.myip.org>
Cc: Robert Love <rml@tech9.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-26 08:56:55 -08:00
Linus Torvalds
53846a21c1 Merge git://git.linux-nfs.org/pub/linux/nfs-2.6
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (103 commits)
  SUNRPC,RPCSEC_GSS: spkm3--fix config dependencies
  SUNRPC,RPCSEC_GSS: spkm3: import contexts using NID_cast5_cbc
  LOCKD: Make nlmsvc_traverse_shares return void
  LOCKD: nlmsvc_traverse_blocks return is unused
  SUNRPC,RPCSEC_GSS: fix krb5 sequence numbers.
  NFSv4: Dont list system.nfs4_acl for filesystems that don't support it.
  SUNRPC,RPCSEC_GSS: remove unnecessary kmalloc of a checksum
  SUNRPC: Ensure rpc_call_async() always calls tk_ops->rpc_release()
  SUNRPC: Fix memory barriers for req->rq_received
  NFS: Fix a race in nfs_sync_inode()
  NFS: Clean up nfs_flush_list()
  NFS: Fix a race with PG_private and nfs_release_page()
  NFSv4: Ensure the callback daemon flushes signals
  SUNRPC: Fix a 'Busy inodes' error in rpc_pipefs
  NFS, NLM: Allow blocking locks to respect signals
  NFS: Make nfs_fhget() return appropriate error values
  NFSv4: Fix an oops in nfs4_fill_super
  lockd: blocks should hold a reference to the nlm_file
  NFSv4: SETCLIENTID_CONFIRM should handle NFS4ERR_DELAY/NFS4ERR_RESOURCE
  NFSv4: Send the delegation stateid for SETATTR calls
  ...
2006-03-25 09:18:27 -08:00
Tobias Klauser
e8c96f8c29 [PATCH] fs: Use ARRAY_SIZE macro
Use ARRAY_SIZE macro instead of sizeof(x)/sizeof(x[0]) and remove a
duplicate of ARRAY_SIZE.  Some trailing whitespaces are also deleted.

Signed-off-by: Tobias Klauser <tklauser@nuerscht.ch>
Cc: David Howells <dhowells@redhat.com>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Nathan Scott <nathans@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-24 07:33:19 -08:00
J. Bruce Fields
5f12191bc0 LOCKD: Make nlmsvc_traverse_shares return void
The nlmsvc_traverse_shares return value is always zero, hence useless.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 23:24:25 -05:00
J. Bruce Fields
f3ee439f43 LOCKD: nlmsvc_traverse_blocks return is unused
Note that we never return non-zero.

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 23:24:13 -05:00
Trond Myklebust
d9f6eb75d4 lockd: blocks should hold a reference to the nlm_file
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:47 -05:00
Trond Myklebust
6041b79192 lockd: Fix a typo in nlmsvc_grant_release()
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:45 -05:00
Trond Myklebust
d471662448 lockd: Add helper for *_RES callbacks
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:45 -05:00
Trond Myklebust
92737230dd NLM: Add nlmclnt_release_call
Add a helper function to simplify the freeing of NLM client requests.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:45 -05:00
Trond Myklebust
e4cd038a45 NLM: Fix nlmclnt_test to not copy private part of locks
The struct file_lock does not carry a properly initialised lock,
so don't copy it as if it were.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:44 -05:00
Trond Myklebust
3a649b8846 NLM: Simplify client locks
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:44 -05:00
Trond Myklebust
35576cba57 NLM: nlmclnt_cancel_callback should accept NLM_LCK_DENIED errors
NLM_LCK_DENIED is a valid error return for an NLM_CANCEL call by the
client.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:41 -05:00
Trond Myklebust
4c060b5310 lockd: Fix Oopses due to list manipulation errors.
The patch "stop abusing file_lock_list introduces a couple of bugs since
the locks may be copied and need to be removed from the lists when they are
destroyed.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:41 -05:00
Christoph Hellwig
26bcbf965f lockd: stop abusing file_lock_list
Currently lockd directly access the file_lock_list from fs/locks.c.
It does so to mark locks granted or reclaimable.  This is very
suboptimal, because a) lockd needs to poke into locks.c internals, and
b) it needs to iterate over all locks in the system for marking locks
granted or reclaimable.

This patch adds lists for granted and reclaimable locks to the nlm_host
structure instead, and adds locks to those.

nlmclnt_lock:
	now adds the lock to h_granted instead of setting the
	NFS_LCK_GRANTED, still O(1)

nlmclnt_mark_reclaim:
	goes away completely, replaced by a list_splice_init.
	Complexity reduced from O(locks in the system) to O(1)

reclaimer:
	iterates over h_reclaim now, complexity reduced from
	O(locks in the system) to O(locks per nlm_host)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:40 -05:00
Trond Myklebust
04266473ec lockd: Make lockd use rpc_new_client() instead of rpc_create_client
When doing NLM_GRANTED requests, lockd may end up blocking if we use
rpc_create_client() due to the synchronous call to rpc_ping(). Instead, use
rpc_new_client().

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:40 -05:00
Trond Myklebust
686517f1ad lockd: Make nlmsvc_create_block() use nlmsvc_lookup_host()
Currently it uses nlmclnt_lookup_host(), which puts the resulting host
structure on a different list.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:39 -05:00
Trond Myklebust
5e1abf8cb7 lockd: Clean up of the server-side GRANTED code
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:39 -05:00
Trond Myklebust
6849c0cab6 lockd: Add refcounting to struct nlm_block
Otherwise, the block may disappear from underneath us when in
nlmsvc_retry_blocked.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:39 -05:00
Trond Myklebust
09c7938c56 lockd: Fix server-side lock blocking code
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:38 -05:00
J. Bruce Fields
7117bf3dfb lockd: Remove FL_LOCKD flag
Currently lockd identifies its own locks using the FL_LOCKD flag.  This
doesn't scale well to multiple lock managers--if we did this in nfsv4 too,
for example, we'd be left with only one free flag bit.

Instead, we just check whether the file manager ops (fl_lmops) set on this
lock are our own.

The only use for this is in nlm_traverse_locks, which uses it to find locks
that need cleaning up when freeing a host or a file.

In the long run it might be nice to do reference counting instead of
traversing all the locks like this....

Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:26 -05:00
Andy Adamson
8dc7c3115b locks,lockd: fix race in nlmsvc_testlock
posix_test_lock() returns a pointer to a struct file_lock which is unprotected
and can be removed while in use by the caller.  Move the conflicting lock from
the return to a parameter, and copy the conflicting lock.

In most cases the caller ends up putting the copy of the conflicting lock on
the stack.  On i386, sizeof(struct file_lock) appears to be about 100 bytes.
We're assuming that's reasonable.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:26 -05:00
Andy Adamson
a85f193e2f lockd: make nlmsvc_lock use only posix_lock_file
Reorganize nlmsvc_lock() to make full use of posix_lock_file(), which does
eveything nlmsvc_lock() needs - no need to call posix_test_lock(),
posix_locks_deadlock(), or posix_block_lock() separately.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:25 -05:00
Andy Adamson
5de0e5024a lockd: simplify nlmsvc_grant_blocked
Reorganize nlmsvc_grant_blocked() to make full use of posix_lock_file().  Note
that there's no need for separate calls to posix_test_lock(),
posix_locks_deadlock(), or posix_block_lock().

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:25 -05:00
Andy Adamson
15dadef946 lockd: clean up nlmsvc_lock
Slightly more consistent dprintk error reporting, consolidate some up()'s.

Signed-off-by: Andy Adamson <andros@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:24 -05:00
Chuck Lever
dead28da8e SUNRPC: eliminate rpc_call()
Clean-up: replace rpc_call() helper with direct call to rpc_call_sync.

This makes NFSv2 and NFSv3 synchronous calls more computationally
efficient, and reduces stack consumption in functions that used to
invoke rpc_call more than once.

Test plan:
Compile kernel with CONFIG_NFS enabled.  Connectathon on NFS version 2,
version 3, and version 4 mount points.

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:23 -05:00
Chuck Lever
cc0175c1dc SUNRPC: display human-readable procedure name in rpc_iostats output
Add fields to the rpc_procinfo struct that allow the display of a
human-readable name for each procedure in the rpc_iostats output.

Also fix it so that the NFSv4 stats are broken up correctly by
sub-procedure number.  NFSv4 uses only two real RPC procedures:
NULL, and COMPOUND.

Test plan:
Mount with NFSv2, NFSv3, and NFSv4, and do "cat /proc/self/mountstats".

Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:22 -05:00
Trond Myklebust
7bab377fcb lockd: Don't expose the process pid to the NLM server
Instead we use the nlm_lockowner->pid.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:06 -05:00
Trond Myklebust
36943fa4b2 NLM: nlm_alloc_call should not immediately fail on signal
Currently, nlm_alloc_call tests for a signal before it even tries to
allocate memory.
Fix it so that it tries at least once.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-03-20 13:44:05 -05:00
Trond Myklebust
30f4e20a0d [PATCH] NLM: Ensure we do not Oops in the case of an unlock
In theory, NLM specs assure us that the server will only reply LCK_GRANTED or
LCK_DENIED_GRACE_PERIOD to our NLM_UNLOCK request.

In practice, we should not assume this to be the case, and the code will
currently Oops if we do.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-14 07:57:18 -08:00
Trond Myklebust
5ac5f9d1ce [PATCH] NLM: Fix the NLM_GRANTED callback checks
If 2 threads attached to the same process are blocking on different locks on
different files (maybe even on different servers) but have the same lock
arguments (i.e.  same offset+length - actually quite common, since most
processes try to lock the entire file) then the first GRANTED call that wakes
one up will also wake the other.

Currently when the NLM_GRANTED callback comes in, lockd walks the list of
blocked locks in search of a match to the lock that the NLM server has
granted.  Although it checks the lock pid, start and end, it fails to check
the filehandle and the server address.

By checking the filehandle and server IP address, we ensure that this only
happens if the locks truly are referencing the same file.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-14 16:09:34 -08:00
Trond Myklebust
aaaa99423b NLM: Ensure that nlmclnt_cancel_callback() doesn't loop forever
If the server returns NLM_LCK_DENIED_NOLOCKS, we currently retry the
 entire NLM_CANCEL request. This may end up looping forever unless the
 server changes its mind (why would it do that, though?).

 Ensure that we limit the number of retries (to 3).

 See bug# 5957 in bugzilla.kernel.org.

 Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2006-02-01 12:52:23 -05:00