Commit Graph

172 Commits

Author SHA1 Message Date
Andy Adamson 9cb8196839 NFSv4.1 handle DS stateid errors
Handle DS READ and WRITE stateid errors by recovering the stateid on the MDS.

NFS4ERR_OLD_STATEID is ignored as the client always sends a
state sequenceid of zero for DS READ and WRITE stateids.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-07 10:53:55 -05:00
Trond Myklebust 2d2f24add1 NFSv4: Simplify the struct nfs4_stateid
Replace the union with the common struct stateid4 as defined in both
RFC3530 and RFC5661. This makes it easier to access the sequence id,
which will again make implementing support for parallel OPEN calls
easier.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-06 10:32:47 -05:00
Trond Myklebust f597c53790 NFSv4: Add helpers for basic copying of stateids
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-06 10:32:46 -05:00
Trond Myklebust 1e3987c305 NFSv4: Rename nfs4_copy_stateid()
It is really a function for selecting the correct stateid to use in a
read or write situation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-06 10:32:46 -05:00
Trond Myklebust a1d0b5eebc NFS: Properly handle the case where the delegation is revoked
If we know that the delegation stateid is bad or revoked, we need to
remove that delegation as soon as possible, and then mark all the
stateids that relied on that delegation for recovery. We cannot use
the delegation as part of the recovery process.

Also note that NFSv4.1 uses a different error code (NFS4ERR_DELEG_REVOKED)
to indicate that the delegation was revoked.

Finally, ensure that setlk() and setattr() can both recover safely from
a revoked delegation.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
2012-03-06 10:32:43 -05:00
Trond Myklebust 8aa0a410af Merge commit 'nfs-for-3.3-4' into nfs-for-next
Conflicts:
	fs/nfs/nfs4proc.c

Back-merge of the upstream kernel in order to fix a conflict with the
slotid type conversion and implementation id patches...
2012-03-03 15:05:56 -05:00
Trond Myklebust 2446ab6070 SUNRPC: Use RCU to dereference the rpc_clnt.cl_xprt field
A migration event will replace the rpc_xprt used by an rpc_clnt.  To
ensure this can be done safely, all references to cl_xprt must now use
a form of rcu_dereference().

Special care is taken with rpc_peeraddr2str(), which returns a pointer
to memory whose lifetime is the same as the rpc_xprt.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[ cel: fix lockdep splats and layering violations ]
[ cel: forward ported to 3.4 ]
[ cel: remove rpc_max_reqs(), add rpc_net_ns() ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-03-02 15:36:38 -05:00
Andy Adamson b6bf6e7d6f NFSv4.1 set highest_used_slotid to NFS4_NO_SLOT
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-17 13:38:03 -05:00
Trond Myklebust b9f9a03150 NFSv4: Ensure we throw out bad delegation stateids on NFS4ERR_BAD_STATEID
To ensure that we don't just reuse the bad delegation when we attempt to
recover the nfs4_state that received the bad stateid error.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
2012-02-09 15:59:21 -05:00
Weston Andros Adamson a030889a01 NFS: start printks w/ NFS: even if __func__ shown
This patch addresses printks that have some context to show that they are
from fs/nfs/, but for the sake of consistency now start with NFS:

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06 18:48:00 -05:00
Weston Andros Adamson f9fd2d9c1f NFS: printks in fs/nfs/ should start with NFS:
Messages like "Got error -10052 from the server on DESTROY_SESSION. Session
has been destroyed regardless" can be confusing to users who aren't very
familiar with NFS.

NOTE: This patch ignores any printks() that start by printing __func__ - that
will be in a separate patch.

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-02-06 18:47:59 -05:00
Trond Myklebust 4601df20fb NFSv4: Avoid thundering herd issues with nfs_release_seqid
Store a pointer to the rpc_task in struct nfs_seqid so that we can wake up
only that request that is able to grab the lock after we've released it.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 19:28:21 -05:00
Trond Myklebust 961a828df6 SUNRPC: Fix potential races in xprt_lock_write_next()
We have to ensure that the wake up from the waitqueue and the assignment
of xprt->snd_task are atomic. We can do this by assigning the snd_task
while under the waitqueue spinlock.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 19:28:08 -05:00
Trond Myklebust 48c22eb210 NFS: Move struct nfs_unique_id into struct nfs_seqid_counter
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 19:28:07 -05:00
Trond Myklebust 7ba127ab9f NFSv4: Move contents of struct rpc_sequence into struct nfs_seqid_counter
Clean up.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 19:28:06 -05:00
Trond Myklebust d2d7ce28a2 NFSv4: Replace lock_owner->ld_id with an ida based allocator
Again, We're unlikely to ever need more than 2^31 simultaneous lock
owners, so let's replace the custom allocator.

Now that there are no more users, we can also get rid of the custom
allocator code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 18:20:28 -05:00
Trond Myklebust 9157c31dd6 NFSv4: Replace state_owner->so_owner_id with an ida based allocator
We're unlikely to ever need more than 2^31 simultaneous open owners,
so let's replace the custom allocator with the generic ida allocator.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 18:20:28 -05:00
Trond Myklebust d1e284d50a NFSv4: Clean up nfs4_get_state_owner
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-31 18:20:28 -05:00
Chuck Lever 0aaaf5c424 NFS: Cache state owners after files are closed
Servers have a finite amount of memory to store NFSv4 open and lock
owners.  Moreover, servers may have a difficult time determining when
they can reap their state owner table, thanks to gray areas in the
NFSv4 protocol specification.  Thus clients should be careful to reuse
state owners when possible.

Currently Linux is not too careful.  When a user has closed all her
files on one mount point, the state owner's reference count goes to
zero, and it is released.  The next OPEN allocates a new one.  A
workload that serially opens and closes files can run through a large
number of open owners this way.

When a state owner's reference count goes to zero, slap it onto a free
list for that nfs_server, with an expiry time.  Garbage collect before
looking for a state owner.  This makes state owners for active users
available for re-use.

Now that there can be unused state owners remaining at umount time,
purge the state owner free list when a server is destroyed.  Also be
sure not to reclaim unused state owners during state recovery.

This change has benefits for the client as well.  For some workloads,
this approach drops the number of OPEN_CONFIRM calls from the same as
the number of OPEN calls, down to just one.  This reduces wire traffic
and thus open(2) latency.  Before this patch, untarring a kernel
source tarball shows the OPEN_CONFIRM call counter steadily increasing
through the test.  With the patch, the OPEN_CONFIRM count remains at 1
throughout the entire untar.

As long as the expiry time is kept short, I don't think garbage
collection should be terribly expensive, although it does bounce the
clp->cl_lock around a bit.

[ At some point we should rationalize the use of the nfs_server
->destroy method. ]

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[Trond: Fixed a garbage collection race and a few efficiency issues]
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-05 11:59:18 -05:00
Chuck Lever 414adf14cd NFS: Clean up nfs4_find_state_owners_locked()
There's no longer a need to check the so_server field in the state
owner, because nowadays the RB tree we search for state owners
contains owners for that only server.

Make nfs4_find_state_owners_locked() use the same tree searching logic
as nfs4_insert_state_owner_locked().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2012-01-05 10:42:42 -05:00
Trond Myklebust 4b44b40e04 NFSv4: Ensure correct locking when accessing the 'lock_states' list
There are currently 2 places in the state recovery code, where we do not
take sufficient precautions before accessing the state->lock_states. In
both cases, we should be holding the state->state_lock.

Reported-by: Pascal Bouchareine <pascal@gandi.net>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-12-09 16:31:52 -05:00
Trond Myklebust 111d489f0f NFSv4.1: Ensure that we handle _all_ SEQUENCE status bits.
Currently, the code assumes that the SEQUENCE status bits are mutually
exclusive. They are not...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 2.6.34]
2011-12-01 16:37:42 -05:00
Trond Myklebust 4f38e4aadc NFSv4: Don't error if we handled it in nfs4_recovery_handle_error
If we handled an error condition, then nfs4_recovery_handle_error should
return '0' so that the state recovery thread can continue.
Also ensure that nfs4_check_lease() continues to abort if we haven't got
any credentials by having it return ENOKEY (which is not handled).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-12-01 16:31:34 -05:00
Trond Myklebust 042b60beb4 NFSv4: renewd needs to be able to handle the NFS4ERR_CB_PATH_DOWN error
The NFSv4 spec does not specify that the server must repeat that error,
so in order to avoid having the delegations revoked, we should handle
it immediately.

Also note that NFS4ERR_CB_PATH_DOWN does in fact renew the lease...

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-08-24 15:07:37 -04:00
Stephen Rothwell 5f00bcb38e Merge branch 'master' into devel and apply fixup from Stephen Rothwell:
vfs/nfs: fixup for nfs_open_context change

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-25 14:53:52 -04:00
Al Viro 643168c2dc nfs4_closedata doesn't need to mess with struct path
instead of path_get()/path_put(), we can just use nfs_sb_{,de}active()
to pin the superblock down.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:41 -04:00
Weston Andros Adamson 78fe0f41d9 NFS: use scope from exchange_id to skip reclaim
can be skipped if the "eir_server_scope" from the exchange_id proc differs from
previous calls.

Also, in the future server_scope will be useful for determining whether client
trunking is available

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-07-12 13:40:27 -04:00
Trond Myklebust 444f72fe7e NFSv4.1: Fix the handling of NFS4ERR_SEQ_MISORDERED errors
Currently, the call to nfs4_schedule_session_recovery() will actually just
result in a test of the lease when what we really want is to force a
session reset.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2011-05-27 17:42:01 -04:00
Trond Myklebust 1bd714f2a1 NFSv4: Ensure that clientid and session establishment can time out
The following patch ensures that we do not get permanently trapped in
the RPC layer when trying to establish a new client id or session.
This again ensures that the state manager can finish in a timely
fashion when the last filesystem to reference the nfs_client exits.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24 14:29:33 -04:00
Trond Myklebust fd954ae124 NFSv4.1: Don't loop forever in nfs4_proc_create_session
If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.

Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-04-24 14:28:18 -04:00
Trond Myklebust 47c2199b6e NFSv4.1: Ensure state manager thread dies on last umount
Currently, the state manager may continue to try recovering state forever
even after the last filesystem to reference that nfs_client has umounted.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2011-04-15 18:28:22 -04:00
Dave Chinner 0444d76ae6 fs: don't use igrab() while holding i_lock
Fix the incorrect use of igrab() inside the i_lock in NFS and Ceph‥

If we are already holding the i_lock, we have a reference to the
inode so we can safely use ihold() to gain an extra reference. This
avoids hangs due to lock recursion on the i_lock now that the
inode_lock is gone and igrab() uses the i_lock itself.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: Ryan Mallon <ryan@bluewatersys.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-29 07:50:34 -07:00
Andy Adamson cbdabc7f8b NFSv4.1: filelayout async error handler
Use our own async error handler.
Mark the layout as failed and retry i/o through the MDS on specified errors.

Update the mds_offset in nfs_readpage_retry so that a failed short-read retry
to a DS gets correctly resent through the MDS.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:43 -05:00
Andy Adamson d6fb79d433 NFSv4.1: new flag for lease time check
Data servers cannot send nfs4_proc_get_lease_time. but still need to setup
state renewal. Add the NFS_CS_CHECK_LEASE_TIME bit to indicate if the lease
time can be checked.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:38:41 -05:00
Trond Myklebust f9feab1e18 NFSv4: nfs4_state_mark_reclaim_nograce() should be static
There are no more external users of nfs4_state_mark_reclaim_nograce() or
nfs4_state_mark_reclaim_reboot(), so mark them as static.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:18:36 -05:00
Trond Myklebust 0400a6b0cb NFSv4/4.1: Fix nfs4_schedule_state_recovery abuses
nfs4_schedule_state_recovery() should only be used when we need to force
the state manager to check the lease. If we just want to start the
state manager in order to handle a state recovery situation, we should be
using nfs4_schedule_state_manager().

This patch fixes the abuses of nfs4_schedule_state_recovery() by replacing
its use with a set of helper functions that do the right thing.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-03-11 15:18:22 -05:00
Andy Adamson 778be232a2 NFS do not find client in NFSv4 pg_authenticate
The information required to find the nfs_client cooresponding to the incoming
back channel request is contained in the NFS layer. Perform minimal checking
in the RPC layer pg_authenticate method, and push more detailed checking into
the NFS layer where the nfs_client can be found.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-25 15:26:51 -05:00
Chuck Lever 24d292b894 NFS: Move cl_state_owners and related fields to the nfs_server struct
NFSv4 migration needs to reassociate state owners from the source to
the destination nfs_server data structures.  To make that easier, move
the cl_state_owners field to the nfs_server struct.  cl_openowner_id
and cl_lockowner_id accompany this move, as they are used in
conjunction with cl_state_owners.

The cl_lock field in the parent nfs_client continues to protect all
three of these fields.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-06 14:47:57 -05:00
Fred Isaman f7e8917a67 pnfs: layout roc code
A layout can request return-on-close.  How this interacts with the
forgetful model of never sending LAYOUTRETURNS is a bit ambiguous.
We forget any layouts marked roc, and wait for them to be completely
forgotten before continuing with the close.  In addition, to compensate
for races with any inflight LAYOUTGETs, and the fact that we do not get
any layout stateid back from the server, we set the barrier to the worst
case scenario of current_seqid + number of outstanding LAYOUTGETS.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-06 14:46:32 -05:00
Andy Adamson 42acd02182 NFS add session back channel draining
Currently session draining only drains the fore channel.
The back channel processing must also be drained.

Use the back channel highest_slot_used to indicate that a callback is being
processed by the callback thread.  Move the session complete to be per channel.

When the session is draininig, wait for any current back channel processing
to complete and stop all new back channel processing by returning NFS4ERR_DELAY
to the back channel client.

Drain the back channel, then the fore channel.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-06 14:46:25 -05:00
Andy Adamson 2c2618c6f2 NFS associate sessionid with callback connection
The sessions based callback service is started prior to the CREATE_SESSION call
so that it can handle CB_NULL requests which can be sent before the
CREATE_SESSION call returns and the session ID is known.

Set the callback sessionid after a sucessful CREATE_SESSION.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2011-01-06 14:46:24 -05:00
Linus Torvalds a4dd8dce14 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
  net/sunrpc: Use static const char arrays
  nfs4: fix channel attribute sanity-checks
  NFSv4.1: Use more sensible names for 'initialize_mountpoint'
  NFSv4.1: pnfs: filelayout: add driver's LAYOUTGET and GETDEVICEINFO infrastructure
  NFSv4.1: pnfs: add LAYOUTGET and GETDEVICEINFO infrastructure
  NFS: client needs to maintain list of inodes with active layouts
  NFS: create and destroy inode's layout cache
  NFSv4.1: pnfs: filelayout: introduce minimal file layout driver
  NFSv4.1: pnfs: full mount/umount infrastructure
  NFS: set layout driver
  NFS: ask for layouttypes during v4 fsinfo call
  NFS: change stateid to be a union
  NFSv4.1: pnfsd, pnfs: protocol level pnfs constants
  SUNRPC: define xdr_decode_opaque_fixed
  NFSD: remove duplicate NFS4_STATEID_SIZE
2010-10-26 09:52:09 -07:00
Linus Torvalds 74eb94b218 Merge branch 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'nfs-for-2.6.37' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6: (67 commits)
  SUNRPC: Cleanup duplicate assignment in rpcauth_refreshcred
  nfs: fix unchecked value
  Ask for time_delta during fsinfo probe
  Revalidate caches on lock
  SUNRPC: After calling xprt_release(), we must restart from call_reserve
  NFSv4: Fix up the 'dircount' hint in encode_readdir
  NFSv4: Clean up nfs4_decode_dirent
  NFSv4: nfs4_decode_dirent must clear entry->fattr->valid
  NFSv4: Fix a regression in decode_getfattr
  NFSv4: Fix up decode_attr_filehandle() to handle the case of empty fh pointer
  NFS: Ensure we check all allocation return values in new readdir code
  NFS: Readdir plus in v4
  NFS: introduce generic decode_getattr function
  NFS: check xdr_decode for errors
  NFS: nfs_readdir_filler catch all errors
  NFS: readdir with vmapped pages
  NFS: remove page size checking code
  NFS: decode_dirent should use an xdr_stream
  SUNRPC: Add a helper function xdr_inline_peek
  NFS: remove readdir plus limit
  ...
2010-10-25 13:48:29 -07:00
Andy Adamson 974cec8ca0 NFS: client needs to maintain list of inodes with active layouts
In particular, server reboot will invalidate all layouts.

Note that in order to have an active layout, we must get a successful response
from the server.  To avoid adding that machinery, this patch just includes a
stub that fakes up a successful return.  Since the layout is never referenced
for io, this is not a problem.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Dean Hildebrand <dhildebz@umich.edu>
Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-24 18:07:10 -04:00
Randy Dunlap 8c7597f6ce nfs: include ratelimit.h, fix nfs4state build error
nfs4state.c uses interfaces from ratelimit.h.  It needs to include
that header file to fix build errors:

fs/nfs/nfs4state.c:1195: warning: type defaults to 'int' in declaration of 'DEFINE_RATELIMIT_STATE'
fs/nfs/nfs4state.c:1195: warning: parameter names (without types) in function declaration
fs/nfs/nfs4state.c:1195: error: invalid storage class for function 'DEFINE_RATELIMIT_STATE'
fs/nfs/nfs4state.c:1195: error: implicit declaration of function '__ratelimit'
fs/nfs/nfs4state.c:1195: error: '_rs' undeclared (first use in this function)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc:	Trond Myklebust <Trond.Myklebust@netapp.com>
Cc:	linux-nfs@vger.kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-23 15:27:29 -04:00
Trond Myklebust 168667c43b NFSv4: The state manager must ignore EKEYEXPIRED.
Otherwise, we cannot recover state correctly.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-10-23 15:27:28 -04:00
Trond Myklebust 6eaa61496f NFSv4: Don't call nfs4_reclaim_complete() on receiving NFS4ERR_STALE_CLIENTID
If the server sends us an NFS4ERR_STALE_CLIENTID while the state management
thread is busy reclaiming state, we do want to treat all state that wasn't
reclaimed before the STALE_CLIENTID as if a network partition occurred (see
the edge conditions described in RFC3530 and RFC5661).
What we do not want to do is to send an nfs4_reclaim_complete(), since we
haven't yet even started reclaiming state after the server rebooted.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-10-19 19:42:53 -04:00
Arnd Bergmann b89f432133 fs/locks.c: prepare for BKL removal
This prepares the removal of the big kernel lock from the
file locking code. We still use the BKL as long as fs/lockd
uses it and ceph might sleep, but we can flip the definition
to a private spinlock as soon as that's done.
All users outside of fs/lockd get converted to use
lock_flocks() instead of lock_kernel() where appropriate.

Based on an earlier patch to use a spinlock from Matthew
Wilcox, who has attempted this a few times before, the
earliest patch from over 10 years ago turned it into
a semaphore, which ended up being slower than the BKL
and was subsequently reverted.

Someone should do some serious performance testing when
this becomes a spinlock, since this has caused problems
before. Using a spinlock should be at least as good
as the BKL in theory, but who knows...

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Sage Weil <sage@newdream.net>
Cc: linux-kernel@vger.kernel.org
Cc: linux-fsdevel@vger.kernel.org
2010-10-05 11:02:04 +02:00
Trond Myklebust 77041ed9b4 NFSv4: Ensure the lockowners are labelled using the fl_owner and/or fl_pid
flock locks want to be labelled using the process pid, while posix locks
want to be labelled using the fl_owner.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-07-30 14:46:10 -04:00
Trond Myklebust d3c7b7ccc1 NFSv4: Add support for the RELEASE_LOCKOWNER operation
This is needed by NFSv4.0 servers in order to keep the number of locking
stateids at a manageable level.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2010-07-30 14:46:10 -04:00