diff options
author | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-01-17 22:57:37 -0500 |
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committer | Trond Myklebust <Trond.Myklebust@netapp.com> | 2012-01-31 19:28:08 -0500 |
commit | 961a828df64979d2a9faeeeee043391670a193b9 (patch) | |
tree | 4b7ddaf1a19c589e3c8ec96b6c732faa507f2899 /fs | |
parent | 2aeb98f498ce37742b743080fdc6c8cf64053599 (diff) |
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>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/nfs/nfs4_fs.h | 1 | ||||
-rw-r--r-- | fs/nfs/nfs4proc.c | 13 | ||||
-rw-r--r-- | fs/nfs/nfs4state.c | 17 |
3 files changed, 17 insertions, 14 deletions
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h index df3d02c3e8c..c45c21a5470 100644 --- a/fs/nfs/nfs4_fs.h +++ b/fs/nfs/nfs4_fs.h @@ -222,6 +222,7 @@ static inline struct nfs4_session *nfs4_get_session(const struct nfs_server *ser return server->nfs_client->cl_session; } +extern bool nfs4_set_task_privileged(struct rpc_task *task, void *dummy); extern int nfs4_setup_sequence(const struct nfs_server *server, struct nfs4_sequence_args *args, struct nfs4_sequence_res *res, struct rpc_task *task); diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 360240cc1e9..828a76590af 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -385,17 +385,20 @@ nfs4_free_slot(struct nfs4_slot_table *tbl, u8 free_slotid) free_slotid, tbl->highest_used_slotid); } +bool nfs4_set_task_privileged(struct rpc_task *task, void *dummy) +{ + rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED); + return true; +} + /* * Signal state manager thread if session fore channel is drained */ static void nfs4_check_drain_fc_complete(struct nfs4_session *ses) { - struct rpc_task *task; - if (!test_bit(NFS4_SESSION_DRAINING, &ses->session_state)) { - task = rpc_wake_up_next(&ses->fc_slot_table.slot_tbl_waitq); - if (task) - rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED); + rpc_wake_up_first(&ses->fc_slot_table.slot_tbl_waitq, + nfs4_set_task_privileged, NULL); return; } diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c index a42e60d3ee5..f0e9881c2aa 100644 --- a/fs/nfs/nfs4state.c +++ b/fs/nfs/nfs4state.c @@ -190,23 +190,22 @@ static int nfs41_setup_state_renewal(struct nfs_client *clp) static void nfs4_end_drain_session(struct nfs_client *clp) { struct nfs4_session *ses = clp->cl_session; + struct nfs4_slot_table *tbl; int max_slots; if (ses == NULL) return; + tbl = &ses->fc_slot_table; if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) { - spin_lock(&ses->fc_slot_table.slot_tbl_lock); - max_slots = ses->fc_slot_table.max_slots; + spin_lock(&tbl->slot_tbl_lock); + max_slots = tbl->max_slots; while (max_slots--) { - struct rpc_task *task; - - task = rpc_wake_up_next(&ses->fc_slot_table. - slot_tbl_waitq); - if (!task) + if (rpc_wake_up_first(&tbl->slot_tbl_waitq, + nfs4_set_task_privileged, + NULL) == NULL) break; - rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED); } - spin_unlock(&ses->fc_slot_table.slot_tbl_lock); + spin_unlock(&tbl->slot_tbl_lock); } } |