NFS: NFSv4.0 transport blocking
Plumb in a mechanism for plugging an NFSv4.0 mount, using the
same infrastructure as NFSv4.1 sessions.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 3b5166c..e9e58cc 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -484,6 +484,67 @@
args->sa_privileged = 1;
}
+static int nfs40_setup_sequence(const struct nfs_server *server,
+ struct nfs4_sequence_args *args,
+ struct nfs4_sequence_res *res,
+ struct rpc_task *task)
+{
+ struct nfs4_slot_table *tbl = server->nfs_client->cl_slot_tbl;
+ struct nfs4_slot *slot;
+
+ /* slot already allocated? */
+ if (res->sr_slot != NULL)
+ goto out_start;
+
+ spin_lock(&tbl->slot_tbl_lock);
+ if (nfs4_slot_tbl_draining(tbl) && !args->sa_privileged)
+ goto out_sleep;
+
+ slot = nfs4_alloc_slot(tbl);
+ if (IS_ERR(slot)) {
+ if (slot == ERR_PTR(-ENOMEM))
+ task->tk_timeout = HZ >> 2;
+ goto out_sleep;
+ }
+ spin_unlock(&tbl->slot_tbl_lock);
+
+ args->sa_slot = slot;
+ res->sr_slot = slot;
+
+out_start:
+ rpc_call_start(task);
+ return 0;
+
+out_sleep:
+ if (args->sa_privileged)
+ rpc_sleep_on_priority(&tbl->slot_tbl_waitq, task,
+ NULL, RPC_PRIORITY_PRIVILEGED);
+ else
+ rpc_sleep_on(&tbl->slot_tbl_waitq, task, NULL);
+ spin_unlock(&tbl->slot_tbl_lock);
+ return -EAGAIN;
+}
+
+static int nfs40_sequence_done(struct rpc_task *task,
+ struct nfs4_sequence_res *res)
+{
+ struct nfs4_slot *slot = res->sr_slot;
+ struct nfs4_slot_table *tbl;
+
+ if (!RPC_WAS_SENT(task))
+ goto out;
+
+ tbl = slot->table;
+ spin_lock(&tbl->slot_tbl_lock);
+ if (!nfs41_wake_and_assign_slot(tbl, slot))
+ nfs4_free_slot(tbl, slot);
+ spin_unlock(&tbl->slot_tbl_lock);
+
+ res->sr_slot = NULL;
+out:
+ return 1;
+}
+
#if defined(CONFIG_NFS_V4_1)
static void nfs41_sequence_free_slot(struct nfs4_sequence_res *res)
@@ -629,6 +690,8 @@
{
if (res->sr_slot == NULL)
return 1;
+ if (!res->sr_slot->table->session)
+ return nfs40_sequence_done(task, res);
return nfs41_sequence_done(task, res);
}
@@ -704,17 +767,15 @@
struct nfs4_session *session = nfs4_get_session(server);
int ret = 0;
- if (session == NULL) {
- rpc_call_start(task);
- goto out;
- }
+ if (!session)
+ return nfs40_setup_sequence(server, args, res, task);
dprintk("--> %s clp %p session %p sr_slot %u\n",
__func__, session->clp, session, res->sr_slot ?
res->sr_slot->slot_nr : NFS4_NO_SLOT);
ret = nfs41_setup_sequence(session, args, res, task);
-out:
+
dprintk("<-- %s status=%d\n", __func__, ret);
return ret;
}
@@ -741,22 +802,23 @@
.rpc_call_done = nfs41_call_sync_done,
};
-#else
+#else /* !CONFIG_NFS_V4_1 */
+
static int nfs4_setup_sequence(const struct nfs_server *server,
struct nfs4_sequence_args *args,
struct nfs4_sequence_res *res,
struct rpc_task *task)
{
- rpc_call_start(task);
- return 0;
+ return nfs40_setup_sequence(server, args, res, task);
}
static int nfs4_sequence_done(struct rpc_task *task,
struct nfs4_sequence_res *res)
{
- return 1;
+ return nfs40_sequence_done(task, res);
}
-#endif /* CONFIG_NFS_V4_1 */
+
+#endif /* !CONFIG_NFS_V4_1 */
static void nfs40_call_sync_prepare(struct rpc_task *task, void *calldata)
{