1 files changed, 455 insertions, 201 deletions

diff --git a/fs/nfs/nfs4state.c b/fs/nfs/nfs4state.c
index 9448c579d41..848f6853c59 100644
--- a/fs/nfs/nfs4state.c
+++ b/fs/nfs/nfs4state.c
@@ -136,16 +136,11 @@ int nfs40_discover_server_trunking(struct nfs_client *clp,
 	clp->cl_confirm = clid.confirm;
 
 	status = nfs40_walk_client_list(clp, result, cred);
-	switch (status) {
-	case -NFS4ERR_STALE_CLIENTID:
-		set_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
-	case 0:
+	if (status == 0) {
 		/* Sustain the lease, even if it's empty.  If the clientid4
 		 * goes stale it's of no use for trunking discovery. */
 		nfs4_schedule_state_renewal(*result);
-		break;
 	}
-
 out:
 	return status;
 }
@@ -159,13 +154,14 @@ struct rpc_cred *nfs4_get_machine_cred_locked(struct nfs_client *clp)
 	return cred;
 }
 
-static void nfs4_clear_machine_cred(struct nfs_client *clp)
+static void nfs4_root_machine_cred(struct nfs_client *clp)
 {
-	struct rpc_cred *cred;
+	struct rpc_cred *cred, *new;
 
+	new = rpc_lookup_machine_cred(NULL);
 	spin_lock(&clp->cl_lock);
 	cred = clp->cl_machine_cred;
-	clp->cl_machine_cred = NULL;
+	clp->cl_machine_cred = new;
 	spin_unlock(&clp->cl_lock);
 	if (cred != NULL)
 		put_rpccred(cred);
@@ -219,67 +215,36 @@ out:
 	return cred;
 }
 
-#if defined(CONFIG_NFS_V4_1)
-
-static int nfs41_setup_state_renewal(struct nfs_client *clp)
+static void nfs4_end_drain_slot_table(struct nfs4_slot_table *tbl)
 {
-	int status;
-	struct nfs_fsinfo fsinfo;
-
-	if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
-		nfs4_schedule_state_renewal(clp);
-		return 0;
-	}
-
-	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);
+	if (test_and_clear_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state)) {
+		spin_lock(&tbl->slot_tbl_lock);
+		nfs41_wake_slot_table(tbl);
+		spin_unlock(&tbl->slot_tbl_lock);
 	}
-
-	return status;
 }
 
-/*
- * Back channel returns NFS4ERR_DELAY for new requests when
- * NFS4_SESSION_DRAINING is set so there is no work to be done when draining
- * is ended.
- */
 static void nfs4_end_drain_session(struct nfs_client *clp)
 {
 	struct nfs4_session *ses = clp->cl_session;
-	struct nfs4_slot_table *tbl;
 
-	if (ses == NULL)
+	if (clp->cl_slot_tbl) {
+		nfs4_end_drain_slot_table(clp->cl_slot_tbl);
 		return;
-	tbl = &ses->fc_slot_table;
-	if (test_and_clear_bit(NFS4_SESSION_DRAINING, &ses->session_state)) {
-		spin_lock(&tbl->slot_tbl_lock);
-		nfs41_wake_slot_table(tbl);
-		spin_unlock(&tbl->slot_tbl_lock);
 	}
-}
 
-/*
- * Signal state manager thread if session fore channel is drained
- */
-void nfs4_session_drain_complete(struct nfs4_session *session,
-		struct nfs4_slot_table *tbl)
-{
-	if (nfs4_session_draining(session))
-		complete(&tbl->complete);
+	if (ses != NULL) {
+		nfs4_end_drain_slot_table(&ses->bc_slot_table);
+		nfs4_end_drain_slot_table(&ses->fc_slot_table);
+	}
 }
 
-static int nfs4_wait_on_slot_tbl(struct nfs4_slot_table *tbl)
+static int nfs4_drain_slot_tbl(struct nfs4_slot_table *tbl)
 {
+	set_bit(NFS4_SLOT_TBL_DRAINING, &tbl->slot_tbl_state);
 	spin_lock(&tbl->slot_tbl_lock);
 	if (tbl->highest_used_slotid != NFS4_NO_SLOT) {
-		INIT_COMPLETION(tbl->complete);
+		reinit_completion(&tbl->complete);
 		spin_unlock(&tbl->slot_tbl_lock);
 		return wait_for_completion_interruptible(&tbl->complete);
 	}
@@ -292,13 +257,41 @@ static int nfs4_begin_drain_session(struct nfs_client *clp)
 	struct nfs4_session *ses = clp->cl_session;
 	int ret = 0;
 
-	set_bit(NFS4_SESSION_DRAINING, &ses->session_state);
+	if (clp->cl_slot_tbl)
+		return nfs4_drain_slot_tbl(clp->cl_slot_tbl);
+
 	/* back channel */
-	ret = nfs4_wait_on_slot_tbl(&ses->bc_slot_table);
+	ret = nfs4_drain_slot_tbl(&ses->bc_slot_table);
 	if (ret)
 		return ret;
 	/* fore channel */
-	return nfs4_wait_on_slot_tbl(&ses->fc_slot_table);
+	return nfs4_drain_slot_tbl(&ses->fc_slot_table);
+}
+
+#if defined(CONFIG_NFS_V4_1)
+
+static int nfs41_setup_state_renewal(struct nfs_client *clp)
+{
+	int status;
+	struct nfs_fsinfo fsinfo;
+
+	if (!test_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state)) {
+		nfs4_schedule_state_renewal(clp);
+		return 0;
+	}
+
+	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 nfs41_finish_session_reset(struct nfs_client *clp)
@@ -358,62 +351,21 @@ int nfs41_discover_server_trunking(struct nfs_client *clp,
 	return nfs41_walk_client_list(clp, result, cred);
 }
 
-struct rpc_cred *nfs4_get_exchange_id_cred(struct nfs_client *clp)
-{
-	struct rpc_cred *cred;
-
-	spin_lock(&clp->cl_lock);
-	cred = nfs4_get_machine_cred_locked(clp);
-	spin_unlock(&clp->cl_lock);
-	return cred;
-}
-
 #endif /* CONFIG_NFS_V4_1 */
 
-static struct rpc_cred *
-nfs4_get_setclientid_cred_server(struct nfs_server *server)
-{
-	struct nfs_client *clp = server->nfs_client;
-	struct rpc_cred *cred = NULL;
-	struct nfs4_state_owner *sp;
-	struct rb_node *pos;
-
-	spin_lock(&clp->cl_lock);
-	pos = rb_first(&server->state_owners);
-	if (pos != NULL) {
-		sp = rb_entry(pos, struct nfs4_state_owner, so_server_node);
-		cred = get_rpccred(sp->so_cred);
-	}
-	spin_unlock(&clp->cl_lock);
-	return cred;
-}
-
 /**
- * nfs4_get_setclientid_cred - Acquire credential for a setclientid operation
+ * nfs4_get_clid_cred - Acquire credential for a setclientid operation
  * @clp: client state handle
  *
  * Returns an rpc_cred with reference count bumped, or NULL.
  */
-struct rpc_cred *nfs4_get_setclientid_cred(struct nfs_client *clp)
+struct rpc_cred *nfs4_get_clid_cred(struct nfs_client *clp)
 {
-	struct nfs_server *server;
 	struct rpc_cred *cred;
 
 	spin_lock(&clp->cl_lock);
 	cred = nfs4_get_machine_cred_locked(clp);
 	spin_unlock(&clp->cl_lock);
-	if (cred != NULL)
-		goto out;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
-		cred = nfs4_get_setclientid_cred_server(server);
-		if (cred != NULL)
-			break;
-	}
-	rcu_read_unlock();
-
-out:
 	return cred;
 }
 
@@ -523,6 +475,8 @@ nfs4_alloc_state_owner(struct nfs_server *server,
 	nfs4_init_seqid_counter(&sp->so_seqid);
 	atomic_set(&sp->so_count, 1);
 	INIT_LIST_HEAD(&sp->so_lru);
+	seqcount_init(&sp->so_reclaim_seqcount);
+	mutex_init(&sp->so_delegreturn_mutex);
 	return sp;
 }
 
@@ -702,6 +656,8 @@ __nfs4_find_state_byowner(struct inode *inode, struct nfs4_state_owner *owner)
 	list_for_each_entry(state, &nfsi->open_states, inode_states) {
 		if (state->owner != owner)
 			continue;
+		if (!nfs4_valid_open_stateid(state))
+			continue;
 		if (atomic_inc_not_zero(&state->count))
 			return state;
 	}
@@ -934,6 +890,7 @@ static struct nfs4_lock_state *nfs4_get_lock_state(struct nfs4_state *state, fl_
  */
 void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 {
+	struct nfs_server *server;
 	struct nfs4_state *state;
 
 	if (lsp == NULL)
@@ -945,11 +902,13 @@ void nfs4_put_lock_state(struct nfs4_lock_state *lsp)
 	if (list_empty(&state->lock_states))
 		clear_bit(LK_STATE_IN_USE, &state->flags);
 	spin_unlock(&state->state_lock);
+	server = state->owner->so_server;
 	if (test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags)) {
-		if (nfs4_release_lockowner(lsp) == 0)
-			return;
-	}
-	nfs4_free_lock_state(lsp->ls_state->owner->so_server, lsp);
+		struct nfs_client *clp = server->nfs_client;
+
+		clp->cl_mvops->free_lock_state(server, lsp);
+	} else
+		nfs4_free_lock_state(server, lsp);
 }
 
 static void nfs4_fl_copy_lock(struct file_lock *dst, struct file_lock *src)
@@ -990,13 +949,14 @@ int nfs4_set_lock_state(struct nfs4_state *state, struct file_lock *fl)
 	return 0;
 }
 
-static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
+static int nfs4_copy_lock_stateid(nfs4_stateid *dst,
+		struct nfs4_state *state,
 		const struct nfs_lockowner *lockowner)
 {
 	struct nfs4_lock_state *lsp;
 	fl_owner_t fl_owner;
 	pid_t fl_pid;
-	bool ret = false;
+	int ret = -ENOENT;
 
 
 	if (lockowner == NULL)
@@ -1009,9 +969,11 @@ static bool nfs4_copy_lock_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 	fl_pid = lockowner->l_pid;
 	spin_lock(&state->state_lock);
 	lsp = __nfs4_find_lock_state(state, fl_owner, fl_pid, NFS4_ANY_LOCK_TYPE);
-	if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
+	if (lsp && test_bit(NFS_LOCK_LOST, &lsp->ls_flags))
+		ret = -EIO;
+	else if (lsp != NULL && test_bit(NFS_LOCK_INITIALIZED, &lsp->ls_flags) != 0) {
 		nfs4_stateid_copy(dst, &lsp->ls_stateid);
-		ret = true;
+		ret = 0;
 	}
 	spin_unlock(&state->state_lock);
 	nfs4_put_lock_state(lsp);
@@ -1021,11 +983,15 @@ out:
 
 static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
 {
+	const nfs4_stateid *src;
 	int seq;
 
 	do {
+		src = &zero_stateid;
 		seq = read_seqbegin(&state->seqlock);
-		nfs4_stateid_copy(dst, &state->stateid);
+		if (test_bit(NFS_OPEN_STATE, &state->flags))
+			src = &state->open_stateid;
+		nfs4_stateid_copy(dst, src);
 	} while (read_seqretry(&state->seqlock, seq));
 }
 
@@ -1033,14 +999,30 @@ static void nfs4_copy_open_stateid(nfs4_stateid *dst, struct nfs4_state *state)
  * Byte-range lock aware utility to initialize the stateid of read/write
  * requests.
  */
-void nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
+int nfs4_select_rw_stateid(nfs4_stateid *dst, struct nfs4_state *state,
 		fmode_t fmode, const struct nfs_lockowner *lockowner)
 {
-	if (nfs4_copy_delegation_stateid(dst, state->inode, fmode))
-		return;
-	if (nfs4_copy_lock_stateid(dst, state, lockowner))
-		return;
+	int ret = nfs4_copy_lock_stateid(dst, state, lockowner);
+	if (ret == -EIO)
+		/* A lost lock - don't even consider delegations */
+		goto out;
+	/* returns true if delegation stateid found and copied */
+	if (nfs4_copy_delegation_stateid(dst, state->inode, fmode)) {
+		ret = 0;
+		goto out;
+	}
+	if (ret != -ENOENT)
+		/* nfs4_copy_delegation_stateid() didn't over-write
+		 * dst, so it still has the lock stateid which we now
+		 * choose to use.
+		 */
+		goto out;
 	nfs4_copy_open_stateid(dst, state);
+	ret = 0;
+out:
+	if (nfs_server_capable(state->inode, NFS_CAP_STATEID_NFSV41))
+		dst->seqid = 0;
+	return ret;
 }
 
 struct nfs_seqid *nfs_alloc_seqid(struct nfs_seqid_counter *counter, gfp_t gfp_mask)
@@ -1084,7 +1066,7 @@ void nfs_free_seqid(struct nfs_seqid *seqid)
 /*
  * Increment the seqid if the OPEN/OPEN_DOWNGRADE/CLOSE succeeded, or
  * failed with a seqid incrementing error -
- * see comments nfs_fs.h:seqid_mutating_error()
+ * see comments nfs4.h:seqid_mutating_error()
  */
 static void nfs_increment_seqid(int status, struct nfs_seqid *seqid)
 {
@@ -1129,7 +1111,7 @@ void nfs_increment_open_seqid(int status, struct nfs_seqid *seqid)
 /*
  * Increment the seqid if the LOCK/LOCKU succeeded, or
  * failed with a seqid incrementing error -
- * see comments nfs_fs.h:seqid_mutating_error()
+ * see comments nfs4.h:seqid_mutating_error()
  */
 void nfs_increment_lock_seqid(int status, struct nfs_seqid *seqid)
 {
@@ -1158,9 +1140,9 @@ static int nfs4_run_state_manager(void *);
 
 static void nfs4_clear_state_manager_bit(struct nfs_client *clp)
 {
-	smp_mb__before_clear_bit();
+	smp_mb__before_atomic();
 	clear_bit(NFS4CLNT_MANAGER_RUNNING, &clp->cl_state);
-	smp_mb__after_clear_bit();
+	smp_mb__after_atomic();
 	wake_up_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING);
 	rpc_wake_up(&clp->cl_rpcwaitq);
 }
@@ -1185,7 +1167,7 @@ void nfs4_schedule_state_manager(struct nfs_client *clp)
 	snprintf(buf, sizeof(buf), "%s-manager",
 			rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 	rcu_read_unlock();
-	task = kthread_run(nfs4_run_state_manager, clp, buf);
+	task = kthread_run(nfs4_run_state_manager, clp, "%s", buf);
 	if (IS_ERR(task)) {
 		printk(KERN_ERR "%s: kthread_run: %ld\n",
 			__func__, PTR_ERR(task));
@@ -1210,20 +1192,74 @@ void nfs4_schedule_lease_recovery(struct nfs_client *clp)
 }
 EXPORT_SYMBOL_GPL(nfs4_schedule_lease_recovery);
 
+/**
+ * nfs4_schedule_migration_recovery - trigger migration recovery
+ *
+ * @server: FSID that is migrating
+ *
+ * Returns zero if recovery has started, otherwise a negative NFS4ERR
+ * value is returned.
+ */
+int nfs4_schedule_migration_recovery(const struct nfs_server *server)
+{
+	struct nfs_client *clp = server->nfs_client;
+
+	if (server->fh_expire_type != NFS4_FH_PERSISTENT) {
+		pr_err("NFS: volatile file handles not supported (server %s)\n",
+				clp->cl_hostname);
+		return -NFS4ERR_IO;
+	}
+
+	if (test_bit(NFS_MIG_FAILED, &server->mig_status))
+		return -NFS4ERR_IO;
+
+	dprintk("%s: scheduling migration recovery for (%llx:%llx) on %s\n",
+			__func__,
+			(unsigned long long)server->fsid.major,
+			(unsigned long long)server->fsid.minor,
+			clp->cl_hostname);
+
+	set_bit(NFS_MIG_IN_TRANSITION,
+			&((struct nfs_server *)server)->mig_status);
+	set_bit(NFS4CLNT_MOVED, &clp->cl_state);
+
+	nfs4_schedule_state_manager(clp);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_migration_recovery);
+
+/**
+ * nfs4_schedule_lease_moved_recovery - start lease-moved recovery
+ *
+ * @clp: server to check for moved leases
+ *
+ */
+void nfs4_schedule_lease_moved_recovery(struct nfs_client *clp)
+{
+	dprintk("%s: scheduling lease-moved recovery for client ID %llx on %s\n",
+		__func__, clp->cl_clientid, clp->cl_hostname);
+
+	set_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state);
+	nfs4_schedule_state_manager(clp);
+}
+EXPORT_SYMBOL_GPL(nfs4_schedule_lease_moved_recovery);
+
 int nfs4_wait_clnt_recover(struct nfs_client *clp)
 {
 	int res;
 
 	might_sleep();
 
+	atomic_inc(&clp->cl_count);
 	res = wait_on_bit(&clp->cl_state, NFS4CLNT_MANAGER_RUNNING,
 			nfs_wait_bit_killable, TASK_KILLABLE);
 	if (res)
-		return res;
-
+		goto out;
 	if (clp->cl_cons_state < 0)
-		return clp->cl_cons_state;
-	return 0;
+		res = clp->cl_cons_state;
+out:
+	nfs_put_client(clp);
+	return res;
 }
 
 int nfs4_client_recover_expired_lease(struct nfs_client *clp)
@@ -1280,7 +1316,7 @@ static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_st
 	return 1;
 }
 
-static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
+int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 {
 	set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 	clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
@@ -1289,14 +1325,17 @@ static int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_s
 	return 1;
 }
 
-void nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
+int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_state *state)
 {
 	struct nfs_client *clp = server->nfs_client;
 
+	if (!nfs4_valid_open_stateid(state))
+		return -EBADF;
 	nfs4_state_mark_reclaim_nograce(clp, state);
 	dprintk("%s: scheduling stateid recovery for server %s\n", __func__,
 			clp->cl_hostname);
 	nfs4_schedule_state_manager(clp);
+	return 0;
 }
 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
 
@@ -1326,6 +1365,27 @@ void nfs_inode_find_state_and_recover(struct inode *inode,
 		nfs4_schedule_state_manager(clp);
 }
 
+static void nfs4_state_mark_open_context_bad(struct nfs4_state *state)
+{
+	struct inode *inode = state->inode;
+	struct nfs_inode *nfsi = NFS_I(inode);
+	struct nfs_open_context *ctx;
+
+	spin_lock(&inode->i_lock);
+	list_for_each_entry(ctx, &nfsi->open_files, list) {
+		if (ctx->state != state)
+			continue;
+		set_bit(NFS_CONTEXT_BAD, &ctx->flags);
+	}
+	spin_unlock(&inode->i_lock);
+}
+
+static void nfs4_state_mark_recovery_failed(struct nfs4_state *state, int error)
+{
+	set_bit(NFS_STATE_RECOVERY_FAILED, &state->flags);
+	nfs4_state_mark_open_context_bad(state);
+}
+
 
 static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_recovery_ops *ops)
 {
@@ -1340,13 +1400,13 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_
 	/* Guard against delegation returns and new lock/unlock calls */
 	down_write(&nfsi->rwsem);
 	/* Protect inode->i_flock using the BKL */
-	lock_flocks();
+	spin_lock(&inode->i_lock);
 	for (fl = inode->i_flock; fl != NULL; fl = fl->fl_next) {
 		if (!(fl->fl_flags & (FL_POSIX|FL_FLOCK)))
 			continue;
 		if (nfs_file_open_context(fl->fl_file)->state != state)
 			continue;
-		unlock_flocks();
+		spin_unlock(&inode->i_lock);
 		status = ops->recover_lock(state, fl);
 		switch (status) {
 			case 0:
@@ -1364,8 +1424,8 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_
 			case -NFS4ERR_CONN_NOT_BOUND_TO_SESSION:
 				goto out;
 			default:
-				printk(KERN_ERR "NFS: %s: unhandled error %d. "
-					"Zeroing state\n", __func__, status);
+				printk(KERN_ERR "NFS: %s: unhandled error %d\n",
+					 __func__, status);
 			case -ENOMEM:
 			case -NFS4ERR_DENIED:
 			case -NFS4ERR_RECLAIM_BAD:
@@ -1373,9 +1433,9 @@ static int nfs4_reclaim_locks(struct nfs4_state *state, const struct nfs4_state_
 				/* kill_proc(fl->fl_pid, SIGLOST, 1); */
 				status = 0;
 		}
-		lock_flocks();
+		spin_lock(&inode->i_lock);
 	}
-	unlock_flocks();
+	spin_unlock(&inode->i_lock);
 out:
 	up_write(&nfsi->rwsem);
 	return status;
@@ -1395,11 +1455,14 @@ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs
 	 * recovering after a network partition or a reboot from a
 	 * server that doesn't support a grace period.
 	 */
-restart:
 	spin_lock(&sp->so_lock);
+	raw_write_seqcount_begin(&sp->so_reclaim_seqcount);
+restart:
 	list_for_each_entry(state, &sp->so_states, open_states) {
 		if (!test_and_clear_bit(ops->state_flag_bit, &state->flags))
 			continue;
+		if (!nfs4_valid_open_stateid(state))
+			continue;
 		if (state->state == 0)
 			continue;
 		atomic_inc(&state->count);
@@ -1408,34 +1471,33 @@ restart:
 		if (status >= 0) {
 			status = nfs4_reclaim_locks(state, ops);
 			if (status >= 0) {
-				spin_lock(&state->state_lock);
-				list_for_each_entry(lock, &state->lock_states, ls_locks) {
-					if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
-						pr_warn_ratelimited("NFS: "
-							"%s: Lock reclaim "
-							"failed!\n", __func__);
+				if (!test_bit(NFS_DELEGATED_STATE, &state->flags)) {
+					spin_lock(&state->state_lock);
+					list_for_each_entry(lock, &state->lock_states, ls_locks) {
+						if (!test_bit(NFS_LOCK_INITIALIZED, &lock->ls_flags))
+							pr_warn_ratelimited("NFS: "
+									    "%s: Lock reclaim "
+									    "failed!\n", __func__);
+					}
+					spin_unlock(&state->state_lock);
 				}
-				spin_unlock(&state->state_lock);
 				nfs4_put_open_state(state);
+				spin_lock(&sp->so_lock);
 				goto restart;
 			}
 		}
 		switch (status) {
 			default:
-				printk(KERN_ERR "NFS: %s: unhandled error %d. "
-					"Zeroing state\n", __func__, status);
+				printk(KERN_ERR "NFS: %s: unhandled error %d\n",
+					__func__, status);
 			case -ENOENT:
 			case -ENOMEM:
 			case -ESTALE:
-				/*
-				 * Open state on this file cannot be recovered
-				 * All we can do is revert to using the zero stateid.
-				 */
-				memset(&state->stateid, 0,
-					sizeof(state->stateid));
-				/* Mark the file as being 'closed' */
-				state->state = 0;
+				/* Open state on this file cannot be recovered */
+				nfs4_state_mark_recovery_failed(state, status);
 				break;
+			case -EAGAIN:
+				ssleep(1);
 			case -NFS4ERR_ADMIN_REVOKED:
 			case -NFS4ERR_STALE_STATEID:
 			case -NFS4ERR_BAD_STATEID:
@@ -1454,12 +1516,17 @@ restart:
 				goto out_err;
 		}
 		nfs4_put_open_state(state);
+		spin_lock(&sp->so_lock);
 		goto restart;
 	}
+	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
 	spin_unlock(&sp->so_lock);
 	return 0;
 out_err:
 	nfs4_put_open_state(state);
+	spin_lock(&sp->so_lock);
+	raw_write_seqcount_end(&sp->so_reclaim_seqcount);
+	spin_unlock(&sp->so_lock);
 	return status;
 }
 
@@ -1522,11 +1589,12 @@ static void nfs4_state_start_reclaim_reboot(struct nfs_client *clp)
 }
 
 static void nfs4_reclaim_complete(struct nfs_client *clp,
-				 const struct nfs4_state_recovery_ops *ops)
+				 const struct nfs4_state_recovery_ops *ops,
+				 struct rpc_cred *cred)
 {
 	/* Notify the server we're done reclaiming our state */
 	if (ops->reclaim_complete)
-		(void)ops->reclaim_complete(clp);
+		(void)ops->reclaim_complete(clp, cred);
 }
 
 static void nfs4_clear_reclaim_server(struct nfs_server *server)
@@ -1571,9 +1639,15 @@ static int nfs4_state_clear_reclaim_reboot(struct nfs_client *clp)
 
 static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
 {
+	const struct nfs4_state_recovery_ops *ops;
+	struct rpc_cred *cred;
+
 	if (!nfs4_state_clear_reclaim_reboot(clp))
 		return;
-	nfs4_reclaim_complete(clp, clp->cl_mvops->reboot_recovery_ops);
+	ops = clp->cl_mvops->reboot_recovery_ops;
+	cred = nfs4_get_clid_cred(clp);
+	nfs4_reclaim_complete(clp, ops, cred);
+	put_rpccred(cred);
 }
 
 static void nfs_delegation_clear_all(struct nfs_client *clp)
@@ -1600,7 +1674,6 @@ static int nfs4_recovery_handle_error(struct nfs_client *clp, int error)
 			nfs4_state_end_reclaim_reboot(clp);
 			break;
 		case -NFS4ERR_STALE_CLIENTID:
-		case -NFS4ERR_LEASE_MOVED:
 			set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
 			nfs4_state_clear_reclaim_reboot(clp);
 			nfs4_state_start_reclaim_reboot(clp);
@@ -1685,13 +1758,17 @@ static int nfs4_check_lease(struct nfs_client *clp)
 	cred = ops->get_state_renewal_cred_locked(clp);
 	spin_unlock(&clp->cl_lock);
 	if (cred == NULL) {
-		cred = nfs4_get_setclientid_cred(clp);
+		cred = nfs4_get_clid_cred(clp);
 		status = -ENOKEY;
 		if (cred == NULL)
 			goto out;
 	}
 	status = ops->renew_lease(clp, cred);
 	put_rpccred(cred);
+	if (status == -ETIMEDOUT) {
+		set_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
+		return 0;
+	}
 out:
 	return nfs4_recovery_handle_error(clp, status);
 }
@@ -1721,10 +1798,6 @@ static int nfs4_handle_reclaim_lease_error(struct nfs_client *clp, int status)
 		clear_bit(NFS4CLNT_LEASE_CONFIRM, &clp->cl_state);
 		return -EPERM;
 	case -EACCES:
-		if (clp->cl_machine_cred == NULL)
-			return -EACCES;
-		/* Handle case where the user hasn't set up machine creds */
-		nfs4_clear_machine_cred(clp);
 	case -NFS4ERR_DELAY:
 	case -ETIMEDOUT:
 	case -EAGAIN:
@@ -1757,7 +1830,7 @@ static int nfs4_establish_lease(struct nfs_client *clp)
 		clp->cl_mvops->reboot_recovery_ops;
 	int status;
 
-	cred = ops->get_clid_cred(clp);
+	cred = nfs4_get_clid_cred(clp);
 	if (cred == NULL)
 		return -ENOENT;
 	status = ops->establish_clid(clp, cred);
@@ -1801,6 +1874,168 @@ static int nfs4_purge_lease(struct nfs_client *clp)
 	return 0;
 }
 
+/*
+ * Try remote migration of one FSID from a source server to a
+ * destination server.  The source server provides a list of
+ * potential destinations.
+ *
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_try_migration(struct nfs_server *server, struct rpc_cred *cred)
+{
+	struct nfs_client *clp = server->nfs_client;
+	struct nfs4_fs_locations *locations = NULL;
+	struct inode *inode;
+	struct page *page;
+	int status, result;
+
+	dprintk("--> %s: FSID %llx:%llx on \"%s\"\n", __func__,
+			(unsigned long long)server->fsid.major,
+			(unsigned long long)server->fsid.minor,
+			clp->cl_hostname);
+
+	result = 0;
+	page = alloc_page(GFP_KERNEL);
+	locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
+	if (page == NULL || locations == NULL) {
+		dprintk("<-- %s: no memory\n", __func__);
+		goto out;
+	}
+
+	inode = server->super->s_root->d_inode;
+	result = nfs4_proc_get_locations(inode, locations, page, cred);
+	if (result) {
+		dprintk("<-- %s: failed to retrieve fs_locations: %d\n",
+			__func__, result);
+		goto out;
+	}
+
+	result = -NFS4ERR_NXIO;
+	if (!(locations->fattr.valid & NFS_ATTR_FATTR_V4_LOCATIONS)) {
+		dprintk("<-- %s: No fs_locations data, migration skipped\n",
+			__func__);
+		goto out;
+	}
+
+	nfs4_begin_drain_session(clp);
+
+	status = nfs4_replace_transport(server, locations);
+	if (status != 0) {
+		dprintk("<-- %s: failed to replace transport: %d\n",
+			__func__, status);
+		goto out;
+	}
+
+	result = 0;
+	dprintk("<-- %s: migration succeeded\n", __func__);
+
+out:
+	if (page != NULL)
+		__free_page(page);
+	kfree(locations);
+	if (result) {
+		pr_err("NFS: migration recovery failed (server %s)\n",
+				clp->cl_hostname);
+		set_bit(NFS_MIG_FAILED, &server->mig_status);
+	}
+	return result;
+}
+
+/*
+ * Returns zero or a negative NFS4ERR status code.
+ */
+static int nfs4_handle_migration(struct nfs_client *clp)
+{
+	const struct nfs4_state_maintenance_ops *ops =
+				clp->cl_mvops->state_renewal_ops;
+	struct nfs_server *server;
+	struct rpc_cred *cred;
+
+	dprintk("%s: migration reported on \"%s\"\n", __func__,
+			clp->cl_hostname);
+
+	spin_lock(&clp->cl_lock);
+	cred = ops->get_state_renewal_cred_locked(clp);
+	spin_unlock(&clp->cl_lock);
+	if (cred == NULL)
+		return -NFS4ERR_NOENT;
+
+	clp->cl_mig_gen++;
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		int status;
+
+		if (server->mig_gen == clp->cl_mig_gen)
+			continue;
+		server->mig_gen = clp->cl_mig_gen;
+
+		if (!test_and_clear_bit(NFS_MIG_IN_TRANSITION,
+						&server->mig_status))
+			continue;
+
+		rcu_read_unlock();
+		status = nfs4_try_migration(server, cred);
+		if (status < 0) {
+			put_rpccred(cred);
+			return status;
+		}
+		goto restart;
+	}
+	rcu_read_unlock();
+	put_rpccred(cred);
+	return 0;
+}
+
+/*
+ * Test each nfs_server on the clp's cl_superblocks list to see
+ * if it's moved to another server.  Stop when the server no longer
+ * returns NFS4ERR_LEASE_MOVED.
+ */
+static int nfs4_handle_lease_moved(struct nfs_client *clp)
+{
+	const struct nfs4_state_maintenance_ops *ops =
+				clp->cl_mvops->state_renewal_ops;
+	struct nfs_server *server;
+	struct rpc_cred *cred;
+
+	dprintk("%s: lease moved reported on \"%s\"\n", __func__,
+			clp->cl_hostname);
+
+	spin_lock(&clp->cl_lock);
+	cred = ops->get_state_renewal_cred_locked(clp);
+	spin_unlock(&clp->cl_lock);
+	if (cred == NULL)
+		return -NFS4ERR_NOENT;
+
+	clp->cl_mig_gen++;
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		struct inode *inode;
+		int status;
+
+		if (server->mig_gen == clp->cl_mig_gen)
+			continue;
+		server->mig_gen = clp->cl_mig_gen;
+
+		rcu_read_unlock();
+
+		inode = server->super->s_root->d_inode;
+		status = nfs4_proc_fsid_present(inode, cred);
+		if (status != -NFS4ERR_MOVED)
+			goto restart;	/* wasn't this one */
+		if (nfs4_try_migration(server, cred) == -NFS4ERR_LEASE_MOVED)
+			goto restart;	/* there are more */
+		goto out;
+	}
+	rcu_read_unlock();
+
+out:
+	put_rpccred(cred);
+	return 0;
+}
+
 /**
  * nfs4_discover_server_trunking - Detect server IP address trunking
  *
@@ -1819,32 +2054,19 @@ int nfs4_discover_server_trunking(struct nfs_client *clp,
 {
 	const struct nfs4_state_recovery_ops *ops =
 				clp->cl_mvops->reboot_recovery_ops;
-	rpc_authflavor_t *flavors, flav, save;
 	struct rpc_clnt *clnt;
 	struct rpc_cred *cred;
-	int i, len, status;
+	int i, status;
 
 	dprintk("NFS: %s: testing '%s'\n", __func__, clp->cl_hostname);
 
-	len = NFS_MAX_SECFLAVORS;
-	flavors = kcalloc(len, sizeof(*flavors), GFP_KERNEL);
-	if (flavors == NULL) {
-		status = -ENOMEM;
-		goto out;
-	}
-	len = rpcauth_list_flavors(flavors, len);
-	if (len < 0) {
-		status = len;
-		goto out_free;
-	}
 	clnt = clp->cl_rpcclient;
-	save = clnt->cl_auth->au_flavor;
 	i = 0;
 
 	mutex_lock(&nfs_clid_init_mutex);
-	status  = -ENOENT;
 again:
-	cred = ops->get_clid_cred(clp);
+	status  = -ENOENT;
+	cred = nfs4_get_clid_cred(clp);
 	if (cred == NULL)
 		goto out_unlock;
 
@@ -1853,35 +2075,42 @@ again:
 	switch (status) {
 	case 0:
 		break;
-
-	case -EACCES:
-		if (clp->cl_machine_cred == NULL)
+	case -ETIMEDOUT:
+		if (clnt->cl_softrtry)
 			break;
-		/* Handle case where the user hasn't set up machine creds */
-		nfs4_clear_machine_cred(clp);
 	case -NFS4ERR_DELAY:
-	case -ETIMEDOUT:
 	case -EAGAIN:
 		ssleep(1);
+	case -NFS4ERR_STALE_CLIENTID:
 		dprintk("NFS: %s after status %d, retrying\n",
 			__func__, status);
 		goto again;
-
+	case -EACCES:
+		if (i++ == 0) {
+			nfs4_root_machine_cred(clp);
+			goto again;
+		}
+		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX)
+			break;
 	case -NFS4ERR_CLID_INUSE:
 	case -NFS4ERR_WRONGSEC:
-		status = -EPERM;
-		if (i >= len)
+		/* No point in retrying if we already used RPC_AUTH_UNIX */
+		if (clnt->cl_auth->au_flavor == RPC_AUTH_UNIX) {
+			status = -EPERM;
 			break;
-
-		flav = flavors[i++];
-		if (flav == save)
-			flav = flavors[i++];
-		clnt = rpc_clone_client_set_auth(clnt, flav);
+		}
+		clnt = rpc_clone_client_set_auth(clnt, RPC_AUTH_UNIX);
 		if (IS_ERR(clnt)) {
 			status = PTR_ERR(clnt);
 			break;
 		}
-		clp->cl_rpcclient = clnt;
+		/* Note: this is safe because we haven't yet marked the
+		 * client as ready, so we are the only user of
+		 * clp->cl_rpcclient
+		 */
+		clnt = xchg(&clp->cl_rpcclient, clnt);
+		rpc_shutdown_client(clnt);
+		clnt = clp->cl_rpcclient;
 		goto again;
 
 	case -NFS4ERR_MINOR_VERS_MISMATCH:
@@ -1892,13 +2121,15 @@ again:
 	case -NFS4ERR_NOT_SAME: /* FixMe: implement recovery
 				 * in nfs4_exchange_id */
 		status = -EKEYEXPIRED;
+		break;
+	default:
+		pr_warn("NFS: %s unhandled error %d. Exiting with error EIO\n",
+				__func__, status);
+		status = -EIO;
 	}
 
 out_unlock:
 	mutex_unlock(&nfs_clid_init_mutex);
-out_free:
-	kfree(flavors);
-out:
 	dprintk("NFS: %s: status = %d\n", __func__, status);
 	return status;
 }
@@ -2000,9 +2231,10 @@ void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
 		nfs41_handle_server_reboot(clp);
 	if (flags & (SEQ4_STATUS_EXPIRED_ALL_STATE_REVOKED |
 			    SEQ4_STATUS_EXPIRED_SOME_STATE_REVOKED |
-			    SEQ4_STATUS_ADMIN_STATE_REVOKED |
-			    SEQ4_STATUS_LEASE_MOVED))
+			    SEQ4_STATUS_ADMIN_STATE_REVOKED))
 		nfs41_handle_state_revoked(clp);
+	if (flags & SEQ4_STATUS_LEASE_MOVED)
+		nfs4_schedule_lease_moved_recovery(clp);
 	if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
 		nfs41_handle_recallable_state_revoked(clp);
 	if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
@@ -2020,10 +2252,20 @@ static int nfs4_reset_session(struct nfs_client *clp)
 	if (!nfs4_has_session(clp))
 		return 0;
 	nfs4_begin_drain_session(clp);
-	cred = nfs4_get_exchange_id_cred(clp);
+	cred = nfs4_get_clid_cred(clp);
 	status = nfs4_proc_destroy_session(clp->cl_session, cred);
-	if (status && status != -NFS4ERR_BADSESSION &&
-	    status != -NFS4ERR_DEADSESSION) {
+	switch (status) {
+	case 0:
+	case -NFS4ERR_BADSESSION:
+	case -NFS4ERR_DEADSESSION:
+		break;
+	case -NFS4ERR_BACK_CHAN_BUSY:
+	case -NFS4ERR_DELAY:
+		set_bit(NFS4CLNT_SESSION_RESET, &clp->cl_state);
+		status = 0;
+		ssleep(1);
+		goto out;
+	default:
 		status = nfs4_recovery_handle_error(clp, status);
 		goto out;
 	}
@@ -2053,7 +2295,7 @@ static int nfs4_bind_conn_to_session(struct nfs_client *clp)
 	if (!nfs4_has_session(clp))
 		return 0;
 	nfs4_begin_drain_session(clp);
-	cred = nfs4_get_exchange_id_cred(clp);
+	cred = nfs4_get_clid_cred(clp);
 	ret = nfs4_proc_bind_conn_to_session(clp, cred);
 	if (cred)
 		put_rpccred(cred);
@@ -2074,7 +2316,6 @@ static int nfs4_bind_conn_to_session(struct nfs_client *clp)
 }
 #else /* CONFIG_NFS_V4_1 */
 static int nfs4_reset_session(struct nfs_client *clp) { return 0; }
-static int nfs4_end_drain_session(struct nfs_client *clp) { return 0; }
 
 static int nfs4_bind_conn_to_session(struct nfs_client *clp)
 {
@@ -2131,7 +2372,20 @@ static void nfs4_state_manager(struct nfs_client *clp)
 			status = nfs4_check_lease(clp);
 			if (status < 0)
 				goto out_error;
-			continue;
+		}
+
+		if (test_and_clear_bit(NFS4CLNT_MOVED, &clp->cl_state)) {
+			section = "migration";
+			status = nfs4_handle_migration(clp);
+			if (status < 0)
+				goto out_error;
+		}
+
+		if (test_and_clear_bit(NFS4CLNT_LEASE_MOVED, &clp->cl_state)) {
+			section = "lease moved";
+			status = nfs4_handle_lease_moved(clp);
+			if (status < 0)
+				goto out_error;
 		}
 
 		/* First recover reboot state... */