Commit Graph

2068 Commits

Author SHA1 Message Date
Linus Torvalds
0d10c2c170 Merge branch 'for-3.17' of git://linux-nfs.org/~bfields/linux
Pull nfsd updates from Bruce Fields:
 "This includes a major rewrite of the NFSv4 state code, which has
  always depended on a single mutex.  As an example, open creates are no
  longer serialized, fixing a performance regression on NFSv3->NFSv4
  upgrades.  Thanks to Jeff, Trond, and Benny, and to Christoph for
  review.

  Also some RDMA fixes from Chuck Lever and Steve Wise, and
  miscellaneous fixes from Kinglong Mee and others"

* 'for-3.17' of git://linux-nfs.org/~bfields/linux: (167 commits)
  svcrdma: remove rdma_create_qp() failure recovery logic
  nfsd: add some comments to the nfsd4 object definitions
  nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers
  nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net
  nfsd: remove nfs4_lock_state: nfs4_laundromat
  nfsd: Remove nfs4_lock_state(): reclaim_complete()
  nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew
  nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()
  nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm
  nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()
  nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close
  nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()
  nfsd: Remove nfs4_lock_state(): nfsd4_release_lockowner
  nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid
  nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()
  nfsd: remove old fault injection infrastructure
  nfsd: add more granular locking to *_delegations fault injectors
  nfsd: add more granular locking to forget_openowners fault injector
  nfsd: add more granular locking to forget_locks fault injector
  nfsd: add a list_head arg to nfsd_foreach_client_lock
  ...
2014-08-09 14:31:18 -07:00
Jeff Layton
14a571a8ec nfsd: add some comments to the nfsd4 object definitions
Add some comments that describe what each of these objects is, and how
they related to one another.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 16:09:20 -04:00
Jeff Layton
b687f6863e nfsd: remove the client_mutex and the nfs4_lock/unlock_state wrappers
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 15:00:54 -04:00
Jeff Layton
74cf76df0f nfsd: remove nfs4_lock_state: nfs4_state_shutdown_net
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:20 -04:00
Jeff Layton
dab6ef2415 nfsd: remove nfs4_lock_state: nfs4_laundromat
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:20 -04:00
Trond Myklebust
05149dd4dc nfsd: Remove nfs4_lock_state(): reclaim_complete()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:19 -04:00
Trond Myklebust
cb86fb1428 nfsd: Remove nfs4_lock_state(): setclientid, setclientid_confirm, renew
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:18 -04:00
Trond Myklebust
3974552dce nfsd: Remove nfs4_lock_state(): exchange_id, create/destroy_session()
Also destroy_clientid and bind_conn_to_session.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:17 -04:00
Trond Myklebust
3234975f47 nfsd: Remove nfs4_lock_state(): nfsd4_open and nfsd4_open_confirm
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:16 -04:00
Trond Myklebust
084d4d4549 nfsd: Remove nfs4_lock_state(): nfsd4_delegreturn()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:15 -04:00
Trond Myklebust
36626a2ecf nfsd: Remove nfs4_lock_state(): nfsd4_open_downgrade + nfsd4_close
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:14 -04:00
Trond Myklebust
2dd7f2ad4e nfsd: Remove nfs4_lock_state(): nfsd4_lock/locku/lockt()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:13 -04:00
Trond Myklebust
51f5e78355 nfsd: Remove nfs4_lock_state(): nfsd4_release_lockowner
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:12 -04:00
Trond Myklebust
e7d5dc19ce nfsd: Remove nfs4_lock_state(): nfsd4_test_stateid/nfsd4_free_stateid
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:12 -04:00
Trond Myklebust
c2d1d6a8f0 nfsd: Remove nfs4_lock_state(): nfs4_preprocess_stateid_op()
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:11 -04:00
Jeff Layton
285abdee53 nfsd: remove old fault injection infrastructure
Remove the old nfsd_for_n_state function and move nfsd_find_client
higher up into the file to get rid of forward declaration. Remove
the struct nfsd_fault_inject_op arguments from the operations as
they are no longer needed by any of them.

Finally, remove the old "standard" get and set routines, which
also eliminates the client_mutex from this code.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:10 -04:00
Jeff Layton
98d5c7c5bd nfsd: add more granular locking to *_delegations fault injectors
...instead of relying on the client_mutex.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:09 -04:00
Jeff Layton
82e05efaec nfsd: add more granular locking to forget_openowners fault injector
...instead of relying on the client_mutex.

Also, fix up the printk output that is generated when the file is read.
It currently says that it's reporting the number of open files, but
it's actually reporting the number of openowners.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:08 -04:00
Jeff Layton
016200c373 nfsd: add more granular locking to forget_locks fault injector
...instead of relying on the client_mutex.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:07 -04:00
Jeff Layton
3738d50e7f nfsd: add a list_head arg to nfsd_foreach_client_lock
In a later patch, we'll want to collect the locks onto a list for later
destruction. If "func" is defined and "collect" is defined, then we'll
add the lock stateid to the list.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:06 -04:00
Jeff Layton
69fc9edf98 nfsd: add nfsd_inject_forget_clients
...which uses the client_lock for protection instead of client_mutex.
Also remove nfsd_forget_client as there are no more callers.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:05 -04:00
Jeff Layton
a0926d1527 nfsd: add a forget_client set_clnt routine
...that relies on the client_lock instead of client_mutex.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:04 -04:00
Jeff Layton
7ec0e36f1a nfsd: add a forget_clients "get" routine with proper locking
Add a new "get" routine for forget_clients that relies on the
client_lock instead of the client_mutex.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:04 -04:00
Jeff Layton
c96223d3b6 nfsd: abstract out the get and set routines into the fault injection ops
Now that we've added more granular locking in other places, it's time
to address the fault injection code. This code is currently quite
reliant on the client_mutex for protection. Start to change this by
adding a new set of fault injection op vectors.

For now they all use the legacy ones. In later patches we'll add new
routines that can deal with more granular locking.

Also, move some of the printk routines into the callers to make the
results of the operations more uniform.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:02 -04:00
Jeff Layton
294ac32e99 nfsd: protect clid and verifier generation with client_lock
The clid counter is a global counter currently. Move it to be a per-net
property so that it can be properly protected by the nn->client_lock
instead of relying on the client_mutex.

The verifier generator is also potentially racy if there are two
simultaneous callers. Generate the verifier when we generate the clid
value, so it's also created under the client_lock. With this, there's
no need to keep two counters as they'd always be in sync anyway, so
just use the clientid_counter for both.

As Trond points out, what would be best is to eventually move this
code to use IDR instead of the hash tables. That would also help ensure
uniqueness, but that's probably best done as a separate project.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:02 -04:00
Jeff Layton
fd699b8a48 nfsd: don't destroy clients that are busy
It's possible that we'll have an in-progress call on some of the clients
while a rogue EXCHANGE_ID or DESTROY_CLIENTID call comes in. Be sure to
try and mark the client expired first, so that the refcount is
respected.

This will only be a problem once the client_mutex is removed.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:55:01 -04:00
Kinglong Mee
fb94d766af NFSD: Put the reference of nfs4_file when freeing stid
After testing nfs4 lock, I restart the nfsd service, got messages as,

[ 5677.403419] nfsd: last server has exited, flushing export cache
[ 5677.463728] =============================================================================
[ 5677.463942] BUG nfsd4_files (Tainted: G    B      OE): Objects remaining in nfsd4_files on kmem_cache_close()
[ 5677.464055] -----------------------------------------------------------------------------

[ 5677.464203] INFO: Slab 0xffffea0000233400 objects=28 used=1 fp=0xffff880008cd3d98 flags=0x3ffc0000004080
[ 5677.464318] CPU: 0 PID: 3772 Comm: rmmod Tainted: G    B      OE 3.16.0-rc2+ #29
[ 5677.464420] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013
[ 5677.464538]  0000000000000000 0000000036af2c9f ffff88000ce97d68 ffffffff816eacfa
[ 5677.464643]  ffffea0000233400 ffff88000ce97e40 ffffffff811cda44 ffffffff00000020
[ 5677.464774]  ffff88000ce97e50 ffff88000ce97e00 656a624f00000008 616d657220737463
[ 5677.464875] Call Trace:
[ 5677.464925]  [<ffffffff816eacfa>] dump_stack+0x45/0x56
[ 5677.464983]  [<ffffffff811cda44>] slab_err+0xb4/0xe0
[ 5677.465040]  [<ffffffff811d0457>] ? __kmalloc+0x117/0x290
[ 5677.465099]  [<ffffffff81100eec>] ? on_each_cpu_cond+0xac/0xf0
[ 5677.465158]  [<ffffffff811d1bc0>] ? kmem_cache_close+0x110/0x2e0
[ 5677.465218]  [<ffffffff811d1be0>] kmem_cache_close+0x130/0x2e0
[ 5677.465279]  [<ffffffff8135a0c1>] ? kobject_cleanup+0x91/0x1b0
[ 5677.465338]  [<ffffffff811d22be>] __kmem_cache_shutdown+0xe/0x10
[ 5677.465399]  [<ffffffff8119bd28>] kmem_cache_destroy+0x48/0x100
[ 5677.465466]  [<ffffffffa05ef78d>] nfsd4_free_slabs+0x2d/0x50 [nfsd]
[ 5677.465530]  [<ffffffffa05fa987>] exit_nfsd+0x34/0x6ad [nfsd]
[ 5677.465589]  [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200
[ 5677.465649]  [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90
[ 5677.465759]  [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b
[ 5677.465822] INFO: Object 0xffff880008cd0000 @offset=0
[ 5677.465882] INFO: Allocated in nfsd4_process_open1+0x61/0x350 [nfsd] age=7599 cpu=0 pid=3253
[ 5677.466115]  __slab_alloc+0x3b0/0x4b1
[ 5677.466166]  kmem_cache_alloc+0x1e4/0x240
[ 5677.466220]  nfsd4_process_open1+0x61/0x350 [nfsd]
[ 5677.466276]  nfsd4_open+0xee/0x860 [nfsd]
[ 5677.466329]  nfsd4_proc_compound+0x4d7/0x7f0 [nfsd]
[ 5677.466384]  nfsd_dispatch+0xbb/0x200 [nfsd]
[ 5677.466447]  svc_process_common+0x453/0x6f0 [sunrpc]
[ 5677.466506]  svc_process+0x103/0x170 [sunrpc]
[ 5677.466559]  nfsd+0x117/0x190 [nfsd]
[ 5677.466609]  kthread+0xd8/0xf0
[ 5677.466656]  ret_from_fork+0x7c/0xb0
[ 5677.466775] kmem_cache_destroy nfsd4_files: Slab cache still has objects
[ 5677.466839] CPU: 0 PID: 3772 Comm: rmmod Tainted: G    B      OE 3.16.0-rc2+ #29
[ 5677.466937] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 07/31/2013
[ 5677.467049]  0000000000000000 0000000036af2c9f ffff88000ce97eb0 ffffffff816eacfa
[ 5677.467150]  ffff880020bb2d00 ffff88000ce97ed0 ffffffff8119bdd9 0000000000000000
[ 5677.467250]  ffffffffa06065c0 ffff88000ce97ee0 ffffffffa05ef78d ffff88000ce97ef0
[ 5677.467351] Call Trace:
[ 5677.467397]  [<ffffffff816eacfa>] dump_stack+0x45/0x56
[ 5677.467454]  [<ffffffff8119bdd9>] kmem_cache_destroy+0xf9/0x100
[ 5677.467516]  [<ffffffffa05ef78d>] nfsd4_free_slabs+0x2d/0x50 [nfsd]
[ 5677.467579]  [<ffffffffa05fa987>] exit_nfsd+0x34/0x6ad [nfsd]
[ 5677.467639]  [<ffffffff81104ac2>] SyS_delete_module+0x162/0x200
[ 5677.467765]  [<ffffffff81013b69>] ? do_notify_resume+0x59/0x90
[ 5677.467826]  [<ffffffff816f2369>] system_call_fastpath+0x16/0x1b

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Fixes: 11b9164ada "nfsd: Add a struct nfs4_file field to struct nfs4_stid"
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-05 10:53:36 -04:00
Jeff Layton
7abea1e8e8 nfsd: don't destroy client if mark_client_expired_locked fails
If it fails, it means that the client is in use and so destroying it
would be bad. Currently, the client_mutex prevents this from happening
but once we remove it, we won't be able to do this.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:26 -04:00
Jeff Layton
97403d95e1 nfsd: move unhash_client_locked call into mark_client_expired_locked
All the callers except for the fault injection code call it directly
afterward, and in the fault injection case it won't hurt to do so
anyway.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:25 -04:00
Jeff Layton
217526e7ec nfsd: protect the close_lru list and oo_last_closed_stid with client_lock
Currently, it's protected by the client_mutex. Move it so that the list
and the fields in the openowner are protected by the client_lock.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:24 -04:00
Trond Myklebust
0a880a28f8 nfsd: Add lockdep assertions to document the nfs4_client/session locking
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:23 -04:00
Trond Myklebust
3e339f964b nfsd: Ensure lookup_clientid() takes client_lock
Ensure that the client lookup is done safely under the client_lock, so
we're not relying on the client_mutex.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:23 -04:00
Trond Myklebust
6b10ad193d nfsd: Protect nfsd4_destroy_clientid using client_lock
...instead of relying on the client_mutex.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:22 -04:00
Jeff Layton
d20c11d86d nfsd: Protect session creation and client confirm using client_lock
In particular, we want to ensure that the move_to_confirmed() is
protected by the nn->client_lock spin lock, so that we can use that when
looking up the clientid etc. instead of relying on the client_mutex.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:21 -04:00
Trond Myklebust
3dbacee6e1 nfsd: Protect unconfirmed client creation using client_lock
...instead of relying on the client_mutex.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:20 -04:00
Trond Myklebust
5cc40fd7b6 nfsd: Move create_client() call outside the lock
For efficiency reasons, and because we want to use spin locks instead
of relying on the client_mutex.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:20 -04:00
Trond Myklebust
425510f5c8 nfsd: Don't require client_lock in free_client
The struct nfs_client is supposed to be invisible and unreferenced
before it gets here.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:19 -04:00
Trond Myklebust
4864af97e0 nfsd: Ensure that the laundromat unhashes the client before releasing locks
If we leave the client on the confirmed/unconfirmed tables, and leave
the sessions visible on the sessionid_hashtbl, then someone might
find them before we've had a chance to destroy them.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:18 -04:00
Trond Myklebust
4beb345b37 nfsd: Ensure struct nfs4_client is unhashed before we try to destroy it
When we remove the client_mutex protection, we will need to ensure
that it can't be found by other threads while we're destroying it.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:17 -04:00
J. Bruce Fields
83e452fee8 nfsd4: fix out of date comment
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:28:16 -04:00
Kinglong Mee
d9499a9571 NFSD: Decrease nfsd_users in nfsd_startup_generic fail
A memory allocation failure could cause nfsd_startup_generic to fail, in
which case nfsd_users wouldn't be incorrectly left elevated.

After nfsd restarts nfsd_startup_generic will then succeed without doing
anything--the first consequence is likely nfs4_start_net finding a bad
laundry_wq and crashing.

Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Fixes: 4539f14981 "nfsd: replace boolean nfsd_up flag by users counter"
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-08-01 16:26:09 -04:00
Jeff Layton
4ae098d327 nfsd: rename unhash_generic_stateid to unhash_ol_stateid
...to better match other functions that deal with open/lock stateids.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:31 -04:00
Jeff Layton
d83017f94c nfsd: don't thrash the cl_lock while freeing an open stateid
When we remove the client_mutex, we'll have a potential race between
FREE_STATEID and CLOSE.

The root of the problem is that we are walking the st_locks list,
dropping the spinlock and then trying to release the persistent
reference to the lockstateid. In between, a FREE_STATEID call can come
along and take the lock, find the stateid and then try to put the
reference. That leads to a double put.

Fix this by not releasing the cl_lock in order to release each lock
stateid. Use put_generic_stateid_locked to unhash them and gather them
onto a list, and free_ol_stateid_reaplist to free any that end up on the
list.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:31 -04:00
Jeff Layton
2c41beb0e5 nfsd: reduce cl_lock thrashing in release_openowner
Releasing an openowner is a bit inefficient as it can potentially thrash
the cl_lock if you have a lot of stateids attached to it. Once we remove
the client_mutex, it'll also potentially be dangerous to do this.

Add some functions to make it easier to defer the part of putting a
generic stateid reference that needs to be done outside the cl_lock while
doing the parts that must be done while holding it under a single lock.

First we unhash each open stateid. Then we call
put_generic_stateid_locked which will put the reference to an
nfs4_ol_stateid. If it turns out to be the last reference, it'll go
ahead and remove the stid from the IDR tree and put it onto the reaplist
using the st_locks list_head.

Then, after dropping the lock we'll call free_ol_stateid_reaplist to
walk the list of stateids that are fully unhashed and ready to be freed,
and free each of them. This function can sleep, so it must be done
outside any spinlocks.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:30 -04:00
Jeff Layton
fc5a96c3b7 nfsd: close potential race in nfsd4_free_stateid
Once we remove the client_mutex, it'll be possible for the sc_type of a
lock stateid to change after it's found and checked, but before we can
go to destroy it. If that happens, we can end up putting the persistent
reference to the stateid more than once, and unhash it more than once.

Fix this by unhashing the lock stateid prior to dropping the cl_lock but
after finding it.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:29 -04:00
Jeff Layton
3c1c995cc2 nfsd: optimize destroy_lockowner cl_lock thrashing
Reduce the cl_lock trashing in destroy_lockowner. Unhash all of the
lockstateids on the lockowner's list. Put the reference under the lock
and see if it was the last one. If so, then add it to a private list
to be destroyed after we drop the lock.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:28 -04:00
Jeff Layton
a819ecc1bb nfsd: add locking to stateowner release
Once we remove the client_mutex, we'll need to properly protect
the stateowner reference counts using the cl_lock.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:27 -04:00
Jeff Layton
882e9d25e1 nfsd: clean up and reorganize release_lockowner
Do more within the main loop, and simplify the function a bit. Also,
there's no need to take a stateowner reference unless we're going to call
release_lockowner.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:27 -04:00
Trond Myklebust
d4f0489f38 nfsd: Move the open owner hash table into struct nfs4_client
Preparation for removing the client_mutex.

Convert the open owner hash table into a per-client table and protect it
using the nfs4_client->cl_lock spin lock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:26 -04:00
Trond Myklebust
c58c6610ec nfsd: Protect adding/removing lock owners using client_lock
Once we remove client mutex protection, we'll need to ensure that
stateowner lookup and creation are atomic between concurrent compounds.
Ensure that alloc_init_lock_stateowner checks the hashtable under the
client_lock before adding a new element.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2014-07-31 14:20:25 -04:00