nfs41: add session reset to state manager
Andy Adamson [Wed, 1 Apr 2009 13:22:39 +0000 (09:22 -0400)]
Move the code to reset a session from the session_reclaimer to the
nfs4_state_manager.  Destroy the session, and create a new one. Treat
NFS4ERR_BADSESSION and NFS4ERR_DEADSESSION as a successful
nfs4_proc_destroy_session. Signal nfs4_proc_create_session that this is a
session reset so that the session slot table is re-used.

If the clientid is stale, set both NFS4CLNT_LEASE_EXPIRED and
NFS4CLNT_SESSION_SETUP bits and retry.

Use a switch statement in nfs4_session_recovery_handle_error for future
patche which will add handling for other errors.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>

[nfs41: session reset in nfs4_recovery_handle_error]
Signed-off-by: Andy Adamson <andros@netapp.com>
[nfs41: reset session on nfs4_do_reclaim session reset error]
    If nfs4_do_reclaim gets a session reset error, nfs4_recovery_handle_error
    will set the NFS4CLNT_SESSION_SETUP bit, and the state manager should
    continue processing to reset the session.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[move nfs4_proc_destroy_session declaration here]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/nfs4_fs.h
fs/nfs/nfs4state.c

index 288717a..7cc1cdd 100644 (file)
@@ -210,6 +210,7 @@ extern int nfs4_setup_sequence(struct nfs_client *clp,
 extern void nfs4_destroy_session(struct nfs4_session *session);
 extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);
 extern int nfs4_proc_create_session(struct nfs_client *, int reset);
+extern int nfs4_proc_destroy_session(struct nfs4_session *);
 #else /* CONFIG_NFS_v4_1 */
 static inline int nfs4_setup_sequence(struct nfs_client *clp,
                struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,
index df5b480..8b7f007 100644 (file)
@@ -1042,6 +1042,14 @@ static void nfs4_recovery_handle_error(struct nfs_client *clp, int error)
                case -NFS4ERR_EXPIRED:
                        set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
                        nfs4_state_start_reclaim_nograce(clp);
+               case -NFS4ERR_BADSESSION:
+               case -NFS4ERR_BADSLOT:
+               case -NFS4ERR_BAD_HIGH_SLOT:
+               case -NFS4ERR_DEADSESSION:
+               case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
+               case -NFS4ERR_SEQ_FALSE_RETRY:
+               case -NFS4ERR_SEQ_MISORDERED:
+                       set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
        }
 }
 
@@ -1114,6 +1122,36 @@ static int nfs4_reclaim_lease(struct nfs_client *clp)
 }
 
 #ifdef CONFIG_NFS_V4_1
+static void nfs4_session_recovery_handle_error(struct nfs_client *clp, int err)
+{
+       switch (err) {
+       case -NFS4ERR_STALE_CLIENTID:
+               set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
+               set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
+       }
+}
+
+static int nfs4_reset_session(struct nfs_client *clp)
+{
+       int status;
+
+       status = nfs4_proc_destroy_session(clp->cl_session);
+       if (status && status != -NFS4ERR_BADSESSION &&
+           status != -NFS4ERR_DEADSESSION) {
+               nfs4_session_recovery_handle_error(clp, status);
+               goto out;
+       }
+
+       memset(clp->cl_session->sess_id.data, 0, NFS4_MAX_SESSIONID_LEN);
+       status = nfs4_proc_create_session(clp, 1);
+       if (status)
+               nfs4_session_recovery_handle_error(clp, status);
+               /* fall through*/
+out:
+       /* Wake up the next rpc task even on error */
+       rpc_wake_up_next(&clp->cl_session->fc_slot_table.slot_tbl_waitq);
+       return status;
+}
 
 static int nfs4_initialize_session(struct nfs_client *clp)
 {
@@ -1131,6 +1169,7 @@ static int nfs4_initialize_session(struct nfs_client *clp)
        return status;
 }
 #else /* CONFIG_NFS_V4_1 */
+static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
 static int nfs4_initialize_session(struct nfs_client *clp) { return 0; }
 #endif /* CONFIG_NFS_V4_1 */
 
@@ -1160,10 +1199,13 @@ static void nfs4_state_manager(struct nfs_client *clp)
                        if (status != 0)
                                continue;
                }
-               /* Setup the session */
+               /* Initialize or reset the session */
                if (nfs4_has_session(clp) &&
                   test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)) {
-                       status = nfs4_initialize_session(clp);
+                       if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
+                               status = nfs4_initialize_session(clp);
+                       else
+                               status = nfs4_reset_session(clp);
                        if (status) {
                                if (status == -NFS4ERR_STALE_CLIENTID)
                                        continue;
@@ -1175,6 +1217,8 @@ static void nfs4_state_manager(struct nfs_client *clp)
                        status = nfs4_do_reclaim(clp, &nfs4_reboot_recovery_ops);
                        if (status == -NFS4ERR_STALE_CLIENTID)
                                continue;
+                       if (test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state))
+                               continue;
                        nfs4_state_end_reclaim_reboot(clp);
                        continue;
                }
@@ -1188,6 +1232,9 @@ static void nfs4_state_manager(struct nfs_client *clp)
                                        continue;
                                if (status == -NFS4ERR_EXPIRED)
                                        continue;
+                               if (test_bit(NFS4CLNT_SESSION_SETUP,
+                                                               &clp->cl_state))
+                                       continue;
                                goto out_error;
                        } else
                                nfs4_state_end_reclaim_nograce(clp);