NFS: Prevent another deadlock in nfs_release_page()
[safe/jmp/linux-2.6] / fs / nfs / nfs4state.c
index 2eb0059..6c5ed51 100644 (file)
@@ -116,6 +116,79 @@ struct rpc_cred *nfs4_get_renew_cred_locked(struct nfs_client *clp)
 
 #if defined(CONFIG_NFS_V4_1)
 
+static int nfs41_setup_state_renewal(struct nfs_client *clp)
+{
+       int status;
+       struct nfs_fsinfo fsinfo;
+
+       status = nfs4_proc_get_lease_time(clp, &fsinfo);
+       if (status == 0) {
+               /* Update lease time and schedule renewal */
+               spin_lock(&clp->cl_lock);
+               clp->cl_lease_time = fsinfo.lease_time * HZ;
+               clp->cl_last_renewal = jiffies;
+               spin_unlock(&clp->cl_lock);
+
+               nfs4_schedule_state_renewal(clp);
+       }
+
+       return status;
+}
+
+static void nfs4_end_drain_session(struct nfs_client *clp)
+{
+       struct nfs4_session *ses = clp->cl_session;
+       int max_slots;
+
+       if (test_and_clear_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state)) {
+               spin_lock(&ses->fc_slot_table.slot_tbl_lock);
+               max_slots = ses->fc_slot_table.max_slots;
+               while (max_slots--) {
+                       struct rpc_task *task;
+
+                       task = rpc_wake_up_next(&ses->fc_slot_table.
+                                               slot_tbl_waitq);
+                       if (!task)
+                               break;
+                       rpc_task_set_priority(task, RPC_PRIORITY_PRIVILEGED);
+               }
+               spin_unlock(&ses->fc_slot_table.slot_tbl_lock);
+       }
+}
+
+static int nfs4_begin_drain_session(struct nfs_client *clp)
+{
+       struct nfs4_session *ses = clp->cl_session;
+       struct nfs4_slot_table *tbl = &ses->fc_slot_table;
+
+       spin_lock(&tbl->slot_tbl_lock);
+       set_bit(NFS4CLNT_SESSION_DRAINING, &clp->cl_state);
+       if (tbl->highest_used_slotid != -1) {
+               INIT_COMPLETION(ses->complete);
+               spin_unlock(&tbl->slot_tbl_lock);
+               return wait_for_completion_interruptible(&ses->complete);
+       }
+       spin_unlock(&tbl->slot_tbl_lock);
+       return 0;
+}
+
+int nfs41_init_clientid(struct nfs_client *clp, struct rpc_cred *cred)
+{
+       int status;
+
+       nfs4_begin_drain_session(clp);
+       status = nfs4_proc_exchange_id(clp, cred);
+       if (status != 0)
+               goto out;
+       status = nfs4_proc_create_session(clp);
+       if (status != 0)
+               goto out;
+       nfs41_setup_state_renewal(clp);
+       nfs_mark_client_ready(clp, NFS_CS_READY);
+out:
+       return status;
+}
+
 struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
 {
        struct rpc_cred *cred;
@@ -693,16 +766,21 @@ struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter)
        return new;
 }
 
-void nfs_free_seqid(struct nfs_seqid *seqid)
+void nfs_release_seqid(struct nfs_seqid *seqid)
 {
        if (!list_empty(&seqid->list)) {
                struct rpc_sequence *sequence = seqid->sequence->sequence;
 
                spin_lock(&sequence->lock);
-               list_del(&seqid->list);
+               list_del_init(&seqid->list);
                spin_unlock(&sequence->lock);
                rpc_wake_up(&sequence->wait);
        }
+}
+
+void nfs_free_seqid(struct nfs_seqid *seqid)
+{
+       nfs_release_seqid(seqid);
        kfree(seqid);
 }
 
@@ -823,7 +901,7 @@ void nfs4_schedule_state_recovery(struct nfs_client *clp)
        nfs4_schedule_state_manager(clp);
 }
 
-static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
+int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 {
 
        set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
@@ -1019,6 +1097,14 @@ static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
        nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_reboot);
 }
 
+static void nfs4_reclaim_complete(struct nfs_client *clp,
+                                const struct nfs4_state_recovery_ops *ops)
+{
+       /* Notify the server we're done reclaiming our state */
+       if (ops->reclaim_complete)
+               (void)ops->reclaim_complete(clp);
+}
+
 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
 {
        struct nfs4_state_owner *sp;
@@ -1028,6 +1114,9 @@ static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
        if (!test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
                return;
 
+       nfs4_reclaim_complete(clp,
+               nfs4_reboot_recovery_ops[clp->cl_minorversion]);
+
        for (pos = rb_first(&clp->cl_state_owners); pos != NULL; pos = rb_next(pos)) {
                sp = rb_entry(pos, struct nfs4_state_owner, so_client_node);
                spin_lock(&sp->so_lock);
@@ -1072,6 +1161,7 @@ static int 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);
+                       break;
                case -NFS4ERR_BADSESSION:
                case -NFS4ERR_BADSLOT:
                case -NFS4ERR_BAD_HIGH_SLOT:
@@ -1079,7 +1169,9 @@ static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
                case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
                case -NFS4ERR_SEQ_FALSE_RETRY:
                case -NFS4ERR_SEQ_MISORDERED:
-                       set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
+                       set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
+                       /* Zero session reset errors */
+                       return 0;
        }
        return error;
 }
@@ -1157,55 +1249,127 @@ 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)
+void nfs41_handle_recall_slot(struct nfs_client *clp)
+{
+       set_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
+       nfs4_schedule_state_recovery(clp);
+}
+
+static void nfs4_reset_all_state(struct nfs_client *clp)
+{
+       if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
+               clp->cl_boot_time = CURRENT_TIME;
+               nfs4_state_start_reclaim_nograce(clp);
+               nfs4_schedule_state_recovery(clp);
+       }
+}
+
+static void nfs41_handle_server_reboot(struct nfs_client *clp)
 {
-       switch (err) {
-       case -NFS4ERR_STALE_CLIENTID:
-               set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
-               set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
+       if (test_and_set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) == 0) {
+               nfs4_state_start_reclaim_reboot(clp);
+               nfs4_schedule_state_recovery(clp);
        }
 }
 
+static void nfs41_handle_state_revoked(struct nfs_client *clp)
+{
+       /* Temporary */
+       nfs4_reset_all_state(clp);
+}
+
+static void nfs41_handle_recallable_state_revoked(struct nfs_client *clp)
+{
+       /* This will need to handle layouts too */
+       nfs_expire_all_delegations(clp);
+}
+
+static void nfs41_handle_cb_path_down(struct nfs_client *clp)
+{
+       nfs_expire_all_delegations(clp);
+       if (test_and_set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) == 0)
+               nfs4_schedule_state_recovery(clp);
+}
+
+void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
+{
+       if (!flags)
+               return;
+       else if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
+               nfs41_handle_server_reboot(clp);
+       else if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
+                           SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
+                           SEQ4_STATUS_ADMIN_STATE_REVOKED |
+                           SEQ4_STATUS_LEASE_MOVED))
+               nfs41_handle_state_revoked(clp);
+       else if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
+               nfs41_handle_recallable_state_revoked(clp);
+       else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
+                           SEQ4_STATUS_BACKCHANNEL_FAULT |
+                           SEQ4_STATUS_CB_PATH_DOWN_SESSION))
+               nfs41_handle_cb_path_down(clp);
+}
+
 static int nfs4_reset_session(struct nfs_client *clp)
 {
        int status;
 
+       nfs4_begin_drain_session(clp);
        status = nfs4_proc_destroy_session(clp->cl_session);
        if (status && status != -NFS4ERR_BADSESSION &&
            status != -NFS4ERR_DEADSESSION) {
-               nfs4_session_recovery_handle_error(clp, status);
+               status = nfs4_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*/
+       status = nfs4_proc_create_session(clp);
+       if (status) {
+               status = nfs4_recovery_handle_error(clp, status);
+               goto out;
+       }
+       /* create_session negotiated new slot table */
+       clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state);
+
+        /* Let the state manager reestablish state */
+       if (!test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
+               nfs41_setup_state_renewal(clp);
 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)
+static int nfs4_recall_slot(struct nfs_client *clp)
 {
-       int status;
+       struct nfs4_slot_table *fc_tbl = &clp->cl_session->fc_slot_table;
+       struct nfs4_channel_attrs *fc_attrs = &clp->cl_session->fc_attrs;
+       struct nfs4_slot *new, *old;
+       int i;
+
+       nfs4_begin_drain_session(clp);
+       new = kmalloc(fc_tbl->target_max_slots * sizeof(struct nfs4_slot),
+                     GFP_KERNEL);
+        if (!new)
+               return -ENOMEM;
 
-       status = nfs4_proc_create_session(clp, 0);
-       if (!status) {
-               nfs_mark_client_ready(clp, NFS_CS_READY);
-       } else if (status == -NFS4ERR_STALE_CLIENTID) {
-               set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
-               set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);
-       } else {
-               nfs_mark_client_ready(clp, status);
-       }
-       return status;
+       spin_lock(&fc_tbl->slot_tbl_lock);
+       for (i = 0; i < fc_tbl->target_max_slots; i++)
+               new[i].seq_nr = fc_tbl->slots[i].seq_nr;
+       old = fc_tbl->slots;
+       fc_tbl->slots = new;
+       fc_tbl->max_slots = fc_tbl->target_max_slots;
+       fc_tbl->target_max_slots = 0;
+       fc_attrs->max_reqs = fc_tbl->max_slots;
+       spin_unlock(&fc_tbl->slot_tbl_lock);
+
+       kfree(old);
+       nfs4_end_drain_session(clp);
+       return 0;
 }
+
 #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; }
+static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
+static int nfs4_recall_slot(struct nfs_client *clp) { return 0; }
 #endif /* CONFIG_NFS_V4_1 */
 
 /* Set NFS4CLNT_LEASE_EXPIRED for all v4.0 errors and for recoverable errors
@@ -1218,6 +1382,7 @@ static void nfs4_set_lease_expired(struct nfs_client *clp, int status)
                case -NFS4ERR_DELAY:
                case -NFS4ERR_CLID_INUSE:
                case -EAGAIN:
+               case -EKEYEXPIRED:
                        break;
 
                case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
@@ -1249,6 +1414,7 @@ static void nfs4_state_manager(struct nfs_client *clp)
                                goto out_error;
                        }
                        clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
+                       set_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state);
                }
 
                if (test_and_clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state)) {
@@ -1260,12 +1426,9 @@ static void nfs4_state_manager(struct nfs_client *clp)
                }
 
                /* Initialize or reset the session */
-               if (test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)
+               if (test_and_clear_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state)
                   && nfs4_has_session(clp)) {
-                       if (clp->cl_cons_state == NFS_CS_SESSION_INITING)
-                               status = nfs4_initialize_session(clp);
-                       else
-                               status = nfs4_reset_session(clp);
+                       status = nfs4_reset_session(clp);
                        if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state))
                                continue;
                        if (status < 0)
@@ -1277,7 +1440,7 @@ static void nfs4_state_manager(struct nfs_client *clp)
                        status = nfs4_do_reclaim(clp,
                                nfs4_reboot_recovery_ops[clp->cl_minorversion]);
                        if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
-                           test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state))
+                           test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state))
                                continue;
                        nfs4_state_end_reclaim_reboot(clp);
                        if (test_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state))
@@ -1291,17 +1454,27 @@ static void nfs4_state_manager(struct nfs_client *clp)
                        status = nfs4_do_reclaim(clp,
                                nfs4_nograce_recovery_ops[clp->cl_minorversion]);
                        if (test_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state) ||
-                           test_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state) ||
+                           test_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state) ||
                            test_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state))
                                continue;
                        if (status < 0)
                                goto out_error;
                }
 
+               nfs4_end_drain_session(clp);
                if (test_and_clear_bit(NFS4CLNT_DELEGRETURN, &clp->cl_state)) {
                        nfs_client_return_marked_delegations(clp);
                        continue;
                }
+               /* Recall session slots */
+               if (test_and_clear_bit(NFS4CLNT_RECALL_SLOT, &clp->cl_state)
+                  && nfs4_has_session(clp)) {
+                       status = nfs4_recall_slot(clp);
+                       if (status < 0)
+                               goto out_error;
+                       continue;
+               }
+
 
                nfs4_clear_state_manager_bit(clp);
                /* Did we race with an attempt to give us more work? */
@@ -1314,6 +1487,7 @@ static void nfs4_state_manager(struct nfs_client *clp)
 out_error:
        printk(KERN_WARNING "Error: state manager failed on NFSv4 server %s"
                        " with error %d\n", clp->cl_hostname, -status);
+       nfs4_end_drain_session(clp);
        nfs4_clear_state_manager_bit(clp);
 }