Merge tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

Pull NFS client updates from Anna Schumaker:
 "Highlights include:

  Stable bugfixes:
   - sunrpc: fix writ espace race causing stalls
   - NFS: Fix inode corruption in nfs_prime_dcache()
   - NFSv4: Don't report revoked delegations as valid in nfs_have_delegation()
   - NFSv4: nfs4_copy_delegation_stateid() must fail if the delegation is invalid
   - NFSv4: Open state recovery must account for file permission changes
   - NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic

  Features:
   - Add support for tracking multiple layout types with an ordered list
   - Add support for using multiple backchannel threads on the client
   - Add support for pNFS file layout session trunking
   - Delay xprtrdma use of DMA API (for device driver removal)
   - Add support for xprtrdma remote invalidation
   - Add support for larger xprtrdma inline thresholds
   - Use a scatter/gather list for sending xprtrdma RPC calls
   - Add support for the CB_NOTIFY_LOCK callback
   - Improve hashing sunrpc auth_creds by using both uid and gid

  Bugfixes:
   - Fix xprtrdma use of DMA API
   - Validate filenames before adding to the dcache
   - Fix corruption of xdr->nwords in xdr_copy_to_scratch
   - Fix setting buffer length in xdr_set_next_buffer()
   - Don't deadlock the state manager on the SEQUENCE status flags
   - Various delegation and stateid related fixes
   - Retry operations if an interrupted slot receives EREMOTEIO
   - Make nfs boot time y2038 safe"

* tag 'nfs-for-4.9-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (100 commits)
  NFSv4.2: Fix a reference leak in nfs42_proc_layoutstats_generic
  fs: nfs: Make nfs boot time y2038 safe
  sunrpc: replace generic auth_cred hash with auth-specific function
  sunrpc: add RPCSEC_GSS hash_cred() function
  sunrpc: add auth_unix hash_cred() function
  sunrpc: add generic_auth hash_cred() function
  sunrpc: add hash_cred() function to rpc_authops struct
  Retry operation on EREMOTEIO on an interrupted slot
  pNFS: Fix atime updates on pNFS clients
  sunrpc: queue work on system_power_efficient_wq
  NFSv4.1: Even if the stateid is OK, we may need to recover the open modes
  NFSv4: If recovery failed for a specific open stateid, then don't retry
  NFSv4: Fix retry issues with nfs41_test/free_stateid
  NFSv4: Open state recovery must account for file permission changes
  NFSv4: Mark the lock and open stateids as invalid after freeing them
  NFSv4: Don't test open_stateid unless it is set
  NFSv4: nfs4_do_handle_exception() handle revoke/expiry of a single stateid
  NFS: Always call nfs_inode_find_state_and_recover() when revoking a delegation
  NFSv4: Fix a race when updating an open_stateid
  NFSv4: Fix a race in nfs_inode_reclaim_delegation()
  ...

fs/nfs/cache_lib.c

@@ -76,7 +76,7 @@ static void nfs_dns_cache_revisit(struct cache_deferred_req *d, int toomany)
 
 	dreq = container_of(d, struct nfs_cache_defer_req, deferred_req);
 
-	complete_all(&dreq->completion);
+	complete(&dreq->completion);
 	nfs_cache_defer_req_put(dreq);
 }
 

fs/nfs/callback.c

@@ -31,8 +31,6 @@
 struct nfs_callback_data {
 	unsigned int users;
 	struct svc_serv *serv;
-	struct svc_rqst *rqst;
-	struct task_struct *task;
 };
 
 static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
@@ -89,15 +87,6 @@ nfs4_callback_svc(void *vrqstp)
 	return 0;
 }
 
-/*
- * Prepare to bring up the NFSv4 callback service
- */
-static struct svc_rqst *
-nfs4_callback_up(struct svc_serv *serv)
-{
-	return svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
-}
-
 #if defined(CONFIG_NFS_V4_1)
 /*
  * The callback service for NFSv4.1 callbacks
@@ -139,29 +128,6 @@ nfs41_callback_svc(void *vrqstp)
 	return 0;
 }
 
-/*
- * Bring up the NFSv4.1 callback service
- */
-static struct svc_rqst *
-nfs41_callback_up(struct svc_serv *serv)
-{
-	struct svc_rqst *rqstp;
-
-	INIT_LIST_HEAD(&serv->sv_cb_list);
-	spin_lock_init(&serv->sv_cb_lock);
-	init_waitqueue_head(&serv->sv_cb_waitq);
-	rqstp = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
-	dprintk("--> %s return %d\n", __func__, PTR_ERR_OR_ZERO(rqstp));
-	return rqstp;
-}
-
-static void nfs_minorversion_callback_svc_setup(struct svc_serv *serv,
-		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
-{
-	*rqstpp = nfs41_callback_up(serv);
-	*callback_svc = nfs41_callback_svc;
-}
-
 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 		struct svc_serv *serv)
 {
@@ -173,13 +139,6 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 		xprt->bc_serv = serv;
 }
 #else
-static void nfs_minorversion_callback_svc_setup(struct svc_serv *serv,
-		struct svc_rqst **rqstpp, int (**callback_svc)(void *vrqstp))
-{
-	*rqstpp = ERR_PTR(-ENOTSUPP);
-	*callback_svc = ERR_PTR(-ENOTSUPP);
-}
-
 static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 		struct svc_serv *serv)
 {
@@ -189,45 +148,22 @@ static inline void nfs_callback_bc_serv(u32 minorversion, struct rpc_xprt *xprt,
 static int nfs_callback_start_svc(int minorversion, struct rpc_xprt *xprt,
 				  struct svc_serv *serv)
 {
-	struct svc_rqst *rqstp;
-	int (*callback_svc)(void *vrqstp);
-	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+	int nrservs = nfs_callback_nr_threads;
 	int ret;
 
 	nfs_callback_bc_serv(minorversion, xprt, serv);
 
-	if (cb_info->task)
+	if (nrservs < NFS4_MIN_NR_CALLBACK_THREADS)
+		nrservs = NFS4_MIN_NR_CALLBACK_THREADS;
+
+	if (serv->sv_nrthreads-1 == nrservs)
 		return 0;
 
-	switch (minorversion) {
-	case 0:
-		/* v4.0 callback setup */
-		rqstp = nfs4_callback_up(serv);
-		callback_svc = nfs4_callback_svc;
-		break;
-	default:
-		nfs_minorversion_callback_svc_setup(serv,
-				&rqstp, &callback_svc);
-	}
-
-	if (IS_ERR(rqstp))
-		return PTR_ERR(rqstp);
-
-	svc_sock_update_bufs(serv);
-
-	cb_info->serv = serv;
-	cb_info->rqst = rqstp;
-	cb_info->task = kthread_create(callback_svc, cb_info->rqst,
-				    "nfsv4.%u-svc", minorversion);
-	if (IS_ERR(cb_info->task)) {
-		ret = PTR_ERR(cb_info->task);
-		svc_exit_thread(cb_info->rqst);
-		cb_info->rqst = NULL;
-		cb_info->task = NULL;
+	ret = serv->sv_ops->svo_setup(serv, NULL, nrservs);
+	if (ret) {
+		serv->sv_ops->svo_setup(serv, NULL, 0);
 		return ret;
 	}
-	rqstp->rq_task = cb_info->task;
-	wake_up_process(cb_info->task);
 	dprintk("nfs_callback_up: service started\n");
 	return 0;
 }
@@ -281,19 +217,41 @@ err_bind:
 	return ret;
 }
 
-static struct svc_serv_ops nfs_cb_sv_ops = {
+static struct svc_serv_ops nfs40_cb_sv_ops = {
+	.svo_function		= nfs4_callback_svc,
 	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
+	.svo_setup		= svc_set_num_threads,
+	.svo_module		= THIS_MODULE,
 };
+#if defined(CONFIG_NFS_V4_1)
+static struct svc_serv_ops nfs41_cb_sv_ops = {
+	.svo_function		= nfs41_callback_svc,
+	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
+	.svo_setup		= svc_set_num_threads,
+	.svo_module		= THIS_MODULE,
+};
+
+struct svc_serv_ops *nfs4_cb_sv_ops[] = {
+	[0] = &nfs40_cb_sv_ops,
+	[1] = &nfs41_cb_sv_ops,
+};
+#else
+struct svc_serv_ops *nfs4_cb_sv_ops[] = {
+	[0] = &nfs40_cb_sv_ops,
+	[1] = NULL,
+};
+#endif
 
 static struct svc_serv *nfs_callback_create_svc(int minorversion)
 {
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
 	struct svc_serv *serv;
+	struct svc_serv_ops *sv_ops;
 
 	/*
 	 * Check whether we're already up and running.
 	 */
-	if (cb_info->task) {
+	if (cb_info->serv) {
 		/*
 		 * Note: increase service usage, because later in case of error
 		 * svc_destroy() will be called.
@@ -302,6 +260,17 @@ static struct svc_serv *nfs_callback_create_svc(int minorversion)
 		return cb_info->serv;
 	}
 
+	switch (minorversion) {
+	case 0:
+		sv_ops = nfs4_cb_sv_ops[0];
+		break;
+	default:
+		sv_ops = nfs4_cb_sv_ops[1];
+	}
+
+	if (sv_ops == NULL)
+		return ERR_PTR(-ENOTSUPP);
+
 	/*
 	 * Sanity check: if there's no task,
 	 * we should be the first user ...
@@ -310,11 +279,12 @@ static struct svc_serv *nfs_callback_create_svc(int minorversion)
 		printk(KERN_WARNING "nfs_callback_create_svc: no kthread, %d users??\n",
 			cb_info->users);
 
-	serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, &nfs_cb_sv_ops);
+	serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, sv_ops);
 	if (!serv) {
 		printk(KERN_ERR "nfs_callback_create_svc: create service failed\n");
 		return ERR_PTR(-ENOMEM);
 	}
+	cb_info->serv = serv;
 	/* As there is only one thread we need to over-ride the
 	 * default maximum of 80 connections
 	 */
@@ -357,6 +327,8 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 	 * thread exits.
 	 */
 err_net:
+	if (!cb_info->users)
+		cb_info->serv = NULL;
 	svc_destroy(serv);
 err_create:
 	mutex_unlock(&nfs_callback_mutex);
@@ -374,18 +346,18 @@ err_start:
 void nfs_callback_down(int minorversion, struct net *net)
 {
 	struct nfs_callback_data *cb_info = &nfs_callback_info[minorversion];
+	struct svc_serv *serv;
 
 	mutex_lock(&nfs_callback_mutex);
-	nfs_callback_down_net(minorversion, cb_info->serv, net);
+	serv = cb_info->serv;
+	nfs_callback_down_net(minorversion, serv, net);
 	cb_info->users--;
-	if (cb_info->users == 0 && cb_info->task != NULL) {
-		kthread_stop(cb_info->task);
-		dprintk("nfs_callback_down: service stopped\n");
-		svc_exit_thread(cb_info->rqst);
+	if (cb_info->users == 0) {
+		svc_get(serv);
+		serv->sv_ops->svo_setup(serv, NULL, 0);
+		svc_destroy(serv);
 		dprintk("nfs_callback_down: service destroyed\n");
 		cb_info->serv = NULL;
-		cb_info->rqst = NULL;
-		cb_info->task = NULL;
 	}
 	mutex_unlock(&nfs_callback_mutex);
 }

fs/nfs/callback.h

@@ -179,6 +179,15 @@ extern __be32 nfs4_callback_devicenotify(
 	struct cb_devicenotifyargs *args,
 	void *dummy, struct cb_process_state *cps);
 
+struct cb_notify_lock_args {
+	struct nfs_fh			cbnl_fh;
+	struct nfs_lowner		cbnl_owner;
+	bool				cbnl_valid;
+};
+
+extern __be32 nfs4_callback_notify_lock(struct cb_notify_lock_args *args,
+					 void *dummy,
+					 struct cb_process_state *cps);
 #endif /* CONFIG_NFS_V4_1 */
 extern int check_gss_callback_principal(struct nfs_client *, struct svc_rqst *);
 extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
@@ -198,6 +207,9 @@ extern void nfs_callback_down(int minorversion, struct net *net);
 #define NFS41_BC_MIN_CALLBACKS 1
 #define NFS41_BC_MAX_CALLBACKS 1
 
+#define NFS4_MIN_NR_CALLBACK_THREADS 1
+
 extern unsigned int nfs_callback_set_tcpport;
+extern unsigned short nfs_callback_nr_threads;
 
 #endif /* __LINUX_FS_NFS_CALLBACK_H */

fs/nfs/callback_proc.c

@@ -628,4 +628,20 @@ out:
 	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
 	return status;
 }
+
+__be32 nfs4_callback_notify_lock(struct cb_notify_lock_args *args, void *dummy,
+				 struct cb_process_state *cps)
+{
+	if (!cps->clp) /* set in cb_sequence */
+		return htonl(NFS4ERR_OP_NOT_IN_SESSION);
+
+	dprintk_rcu("NFS: CB_NOTIFY_LOCK request from %s\n",
+		rpc_peeraddr2str(cps->clp->cl_rpcclient, RPC_DISPLAY_ADDR));
+
+	/* Don't wake anybody if the string looked bogus */
+	if (args->cbnl_valid)
+		__wake_up(&cps->clp->cl_lock_waitq, TASK_NORMAL, 0, args);
+
+	return htonl(NFS4_OK);
+}
 #endif /* CONFIG_NFS_V4_1 */

fs/nfs/callback_xdr.c

@@ -35,6 +35,7 @@
 					 (1 + 3) * 4) // seqid, 3 slotids
 #define CB_OP_RECALLANY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #define CB_OP_RECALLSLOT_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
+#define CB_OP_NOTIFY_LOCK_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
 #endif /* CONFIG_NFS_V4_1 */
 
 #define NFSDBG_FACILITY NFSDBG_CALLBACK
@@ -72,7 +73,7 @@ static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
 	return xdr_ressize_check(rqstp, p);
 }
 
-static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
+static __be32 *read_buf(struct xdr_stream *xdr, size_t nbytes)
 {
 	__be32 *p;
 
@@ -534,6 +535,49 @@ static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
 	return 0;
 }
 
+static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
+{
+	__be32		*p;
+	unsigned int	len;
+
+	p = read_buf(xdr, 12);
+	if (unlikely(p == NULL))
+		return htonl(NFS4ERR_BADXDR);
+
+	p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
+	len = be32_to_cpu(*p);
+
+	p = read_buf(xdr, len);
+	if (unlikely(p == NULL))
+		return htonl(NFS4ERR_BADXDR);
+
+	/* Only try to decode if the length is right */
+	if (len == 20) {
+		p += 2;	/* skip "lock id:" */
+		args->cbnl_owner.s_dev = be32_to_cpu(*p++);
+		xdr_decode_hyper(p, &args->cbnl_owner.id);
+		args->cbnl_valid = true;
+	} else {
+		args->cbnl_owner.s_dev = 0;
+		args->cbnl_owner.id = 0;
+		args->cbnl_valid = false;
+	}
+	return 0;
+}
+
+static __be32 decode_notify_lock_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_notify_lock_args *args)
+{
+	__be32 status;
+
+	status = decode_fh(xdr, &args->cbnl_fh);
+	if (unlikely(status != 0))
+		goto out;
+	status = decode_lockowner(xdr, args);
+out:
+	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
+	return status;
+}
+
 #endif /* CONFIG_NFS_V4_1 */
 
 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
@@ -746,6 +790,7 @@ preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 	case OP_CB_RECALL_SLOT:
 	case OP_CB_LAYOUTRECALL:
 	case OP_CB_NOTIFY_DEVICEID:
+	case OP_CB_NOTIFY_LOCK:
 		*op = &callback_ops[op_nr];
 		break;
 
@@ -753,7 +798,6 @@ preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
 	case OP_CB_PUSH_DELEG:
 	case OP_CB_RECALLABLE_OBJ_AVAIL:
 	case OP_CB_WANTS_CANCELLED:
-	case OP_CB_NOTIFY_LOCK:
 		return htonl(NFS4ERR_NOTSUPP);
 
 	default:
@@ -1006,6 +1050,11 @@ static struct callback_op callback_ops[] = {
 		.decode_args = (callback_decode_arg_t)decode_recallslot_args,
 		.res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
 	},
+	[OP_CB_NOTIFY_LOCK] = {
+		.process_op = (callback_process_op_t)nfs4_callback_notify_lock,
+		.decode_args = (callback_decode_arg_t)decode_notify_lock_args,
+		.res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
+	},
 #endif /* CONFIG_NFS_V4_1 */
 };
 

fs/nfs/client.c

@@ -313,7 +313,10 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
 			continue;
 		/* Match the full socket address */
 		if (!rpc_cmp_addr_port(sap, clap))
-			continue;
+			/* Match all xprt_switch full socket addresses */
+			if (!rpc_clnt_xprt_switch_has_addr(clp->cl_rpcclient,
+							   sap))
+				continue;
 
 		atomic_inc(&clp->cl_count);
 		return clp;
@@ -785,7 +788,8 @@ int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs
 	}
 
 	fsinfo.fattr = fattr;
-	fsinfo.layouttype = 0;
+	fsinfo.nlayouttypes = 0;
+	memset(fsinfo.layouttype, 0, sizeof(fsinfo.layouttype));
 	error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
 	if (error < 0)
 		goto out_error;
@@ -1078,7 +1082,7 @@ void nfs_clients_init(struct net *net)
 	idr_init(&nn->cb_ident_idr);
 #endif
 	spin_lock_init(&nn->nfs_client_lock);
-	nn->boot_time = CURRENT_TIME;
+	nn->boot_time = ktime_get_real();
 }
 
 #ifdef CONFIG_PROC_FS

fs/nfs/delegation.c

@@ -41,6 +41,17 @@ void nfs_mark_delegation_referenced(struct nfs_delegation *delegation)
 	set_bit(NFS_DELEGATION_REFERENCED, &delegation->flags);
 }
 
+static bool
+nfs4_is_valid_delegation(const struct nfs_delegation *delegation,
+		fmode_t flags)
+{
+	if (delegation != NULL && (delegation->type & flags) == flags &&
+	    !test_bit(NFS_DELEGATION_REVOKED, &delegation->flags) &&
+	    !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags))
+		return true;
+	return false;
+}
+
 static int
 nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark)
 {
@@ -50,8 +61,7 @@ nfs4_do_check_delegation(struct inode *inode, fmode_t flags, bool mark)
 	flags &= FMODE_READ|FMODE_WRITE;
 	rcu_read_lock();
 	delegation = rcu_dereference(NFS_I(inode)->delegation);
-	if (delegation != NULL && (delegation->type & flags) == flags &&
-	    !test_bit(NFS_DELEGATION_RETURNING, &delegation->flags)) {
+	if (nfs4_is_valid_delegation(delegation, flags)) {
 		if (mark)
 			nfs_mark_delegation_referenced(delegation);
 		ret = 1;
@@ -185,15 +195,13 @@ void nfs_inode_reclaim_delegation(struct inode *inode, struct rpc_cred *cred,
 			rcu_read_unlock();
 			put_rpccred(oldcred);
 			trace_nfs4_reclaim_delegation(inode, res->delegation_type);
-		} else {
-			/* We appear to have raced with a delegation return. */
-			spin_unlock(&delegation->lock);
-			rcu_read_unlock();
-			nfs_inode_set_delegation(inode, cred, res);
+			return;
 		}
-	} else {
-		rcu_read_unlock();
+		/* We appear to have raced with a delegation return. */
+		spin_unlock(&delegation->lock);
 	}
+	rcu_read_unlock();
+	nfs_inode_set_delegation(inode, cred, res);
 }
 
 static int nfs_do_return_delegation(struct inode *inode, struct nfs_delegation *delegation, int issync)
@@ -642,28 +650,49 @@ static void nfs_client_mark_return_unused_delegation_types(struct nfs_client *cl
 	rcu_read_unlock();
 }
 
-static void nfs_revoke_delegation(struct inode *inode)
+static void nfs_mark_delegation_revoked(struct nfs_server *server,
+		struct nfs_delegation *delegation)
 {
-	struct nfs_delegation *delegation;
-	rcu_read_lock();
-	delegation = rcu_dereference(NFS_I(inode)->delegation);
-	if (delegation != NULL) {
-		set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
-		nfs_mark_return_delegation(NFS_SERVER(inode), delegation);
-	}
-	rcu_read_unlock();
+	set_bit(NFS_DELEGATION_REVOKED, &delegation->flags);
+	delegation->stateid.type = NFS4_INVALID_STATEID_TYPE;
+	nfs_mark_return_delegation(server, delegation);
 }
 
-void nfs_remove_bad_delegation(struct inode *inode)
+static bool nfs_revoke_delegation(struct inode *inode,
+		const nfs4_stateid *stateid)
+{
+	struct nfs_delegation *delegation;
+	nfs4_stateid tmp;
+	bool ret = false;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (delegation == NULL)
+		goto out;
+	if (stateid == NULL) {
+		nfs4_stateid_copy(&tmp, &delegation->stateid);
+		stateid = &tmp;
+	} else if (!nfs4_stateid_match(stateid, &delegation->stateid))
+		goto out;
+	nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation);
+	ret = true;
+out:
+	rcu_read_unlock();
+	if (ret)
+		nfs_inode_find_state_and_recover(inode, stateid);
+	return ret;
+}
+
+void nfs_remove_bad_delegation(struct inode *inode,
+		const nfs4_stateid *stateid)
 {
 	struct nfs_delegation *delegation;
 
-	nfs_revoke_delegation(inode);
+	if (!nfs_revoke_delegation(inode, stateid))
+		return;
 	delegation = nfs_inode_detach_delegation(inode);
-	if (delegation) {
-		nfs_inode_find_state_and_recover(inode, &delegation->stateid);
+	if (delegation)
 		nfs_free_delegation(delegation);
-	}
 }
 EXPORT_SYMBOL_GPL(nfs_remove_bad_delegation);
 
@@ -786,8 +815,15 @@ static void nfs_delegation_mark_reclaim_server(struct nfs_server *server)
 {
 	struct nfs_delegation *delegation;
 
-	list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+	list_for_each_entry_rcu(delegation, &server->delegations, super_list) {
+		/*
+		 * If the delegation may have been admin revoked, then we
+		 * cannot reclaim it.
+		 */
+		if (test_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags))
+			continue;
 		set_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+	}
 }
 
 /**
@@ -851,6 +887,141 @@ restart:
 	rcu_read_unlock();
 }
 
+static inline bool nfs4_server_rebooted(const struct nfs_client *clp)
+{
+	return (clp->cl_state & (BIT(NFS4CLNT_CHECK_LEASE) |
+				BIT(NFS4CLNT_LEASE_EXPIRED) |
+				BIT(NFS4CLNT_SESSION_RESET))) != 0;
+}
+
+static void nfs_mark_test_expired_delegation(struct nfs_server *server,
+	    struct nfs_delegation *delegation)
+{
+	if (delegation->stateid.type == NFS4_INVALID_STATEID_TYPE)
+		return;
+	clear_bit(NFS_DELEGATION_NEED_RECLAIM, &delegation->flags);
+	set_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
+	set_bit(NFS4CLNT_DELEGATION_EXPIRED, &server->nfs_client->cl_state);
+}
+
+static void nfs_inode_mark_test_expired_delegation(struct nfs_server *server,
+		struct inode *inode)
+{
+	struct nfs_delegation *delegation;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (delegation)
+		nfs_mark_test_expired_delegation(server, delegation);
+	rcu_read_unlock();
+
+}
+
+static void nfs_delegation_mark_test_expired_server(struct nfs_server *server)
+{
+	struct nfs_delegation *delegation;
+
+	list_for_each_entry_rcu(delegation, &server->delegations, super_list)
+		nfs_mark_test_expired_delegation(server, delegation);
+}
+
+/**
+ * nfs_mark_test_expired_all_delegations - mark all delegations for testing
+ * @clp: nfs_client to process
+ *
+ * Iterates through all the delegations associated with this server and
+ * marks them as needing to be checked for validity.
+ */
+void nfs_mark_test_expired_all_delegations(struct nfs_client *clp)
+{
+	struct nfs_server *server;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link)
+		nfs_delegation_mark_test_expired_server(server);
+	rcu_read_unlock();
+}
+
+/**
+ * nfs_reap_expired_delegations - reap expired delegations
+ * @clp: nfs_client to process
+ *
+ * Iterates through all the delegations associated with this server and
+ * checks if they have may have been revoked. This function is usually
+ * expected to be called in cases where the server may have lost its
+ * lease.
+ */
+void nfs_reap_expired_delegations(struct nfs_client *clp)
+{
+	const struct nfs4_minor_version_ops *ops = clp->cl_mvops;
+	struct nfs_delegation *delegation;
+	struct nfs_server *server;
+	struct inode *inode;
+	struct rpc_cred *cred;
+	nfs4_stateid stateid;
+
+restart:
+	rcu_read_lock();
+	list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) {
+		list_for_each_entry_rcu(delegation, &server->delegations,
+								super_list) {
+			if (test_bit(NFS_DELEGATION_RETURNING,
+						&delegation->flags))
+				continue;
+			if (test_bit(NFS_DELEGATION_TEST_EXPIRED,
+						&delegation->flags) == 0)
+				continue;
+			if (!nfs_sb_active(server->super))
+				continue;
+			inode = nfs_delegation_grab_inode(delegation);
+			if (inode == NULL) {
+				rcu_read_unlock();
+				nfs_sb_deactive(server->super);
+				goto restart;
+			}
+			cred = get_rpccred_rcu(delegation->cred);
+			nfs4_stateid_copy(&stateid, &delegation->stateid);
+			clear_bit(NFS_DELEGATION_TEST_EXPIRED, &delegation->flags);
+			rcu_read_unlock();
+			if (cred != NULL &&
+			    ops->test_and_free_expired(server, &stateid, cred) < 0) {
+				nfs_revoke_delegation(inode, &stateid);
+				nfs_inode_find_state_and_recover(inode, &stateid);
+			}
+			put_rpccred(cred);
+			if (nfs4_server_rebooted(clp)) {
+				nfs_inode_mark_test_expired_delegation(server,inode);
+				iput(inode);
+				nfs_sb_deactive(server->super);
+				return;
+			}
+			iput(inode);
+			nfs_sb_deactive(server->super);
+			goto restart;
+		}
+	}
+	rcu_read_unlock();
+}
+
+void nfs_inode_find_delegation_state_and_recover(struct inode *inode,
+		const nfs4_stateid *stateid)
+{
+	struct nfs_client *clp = NFS_SERVER(inode)->nfs_client;
+	struct nfs_delegation *delegation;
+	bool found = false;
+
+	rcu_read_lock();
+	delegation = rcu_dereference(NFS_I(inode)->delegation);
+	if (delegation &&
+	    nfs4_stateid_match_other(&delegation->stateid, stateid)) {
+		nfs_mark_test_expired_delegation(NFS_SERVER(inode), delegation);
+		found = true;
+	}
+	rcu_read_unlock();
+	if (found)
+		nfs4_schedule_state_manager(clp);
+}
+
 /**
  * nfs_delegations_present - check for existence of delegations
  * @clp: client state handle
@@ -893,7 +1064,7 @@ bool nfs4_copy_delegation_stateid(struct inode *inode, fmode_t flags,
 	flags &= FMODE_READ|FMODE_WRITE;
 	rcu_read_lock();
 	delegation = rcu_dereference(nfsi->delegation);
-	ret = (delegation != NULL && (delegation->type & flags) == flags);
+	ret = nfs4_is_valid_delegation(delegation, flags);
 	if (ret) {
 		nfs4_stateid_copy(dst, &delegation->stateid);
 		nfs_mark_delegation_referenced(delegation);

fs/nfs/delegation.h

@@ -32,6 +32,7 @@ enum {
 	NFS_DELEGATION_REFERENCED,
 	NFS_DELEGATION_RETURNING,
 	NFS_DELEGATION_REVOKED,
+	NFS_DELEGATION_TEST_EXPIRED,
 };
 
 int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct nfs_openres *res);
@@ -47,11 +48,14 @@ void nfs_expire_unused_delegation_types(struct nfs_client *clp, fmode_t flags);
 void nfs_expire_unreferenced_delegations(struct nfs_client *clp);
 int nfs_client_return_marked_delegations(struct nfs_client *clp);
 int nfs_delegations_present(struct nfs_client *clp);
-void nfs_remove_bad_delegation(struct inode *inode);
+void nfs_remove_bad_delegation(struct inode *inode, const nfs4_stateid *stateid);
 
 void nfs_delegation_mark_reclaim(struct nfs_client *clp);
 void nfs_delegation_reap_unclaimed(struct nfs_client *clp);
 
+void nfs_mark_test_expired_all_delegations(struct nfs_client *clp);
+void nfs_reap_expired_delegations(struct nfs_client *clp);
+
 /* NFSv4 delegation-related procedures */
 int nfs4_proc_delegreturn(struct inode *inode, struct rpc_cred *cred, const nfs4_stateid *stateid, int issync);
 int nfs4_open_delegation_recall(struct nfs_open_context *ctx, struct nfs4_state *state, const nfs4_stateid *stateid, fmode_t type);
@@ -62,6 +66,8 @@ void nfs_mark_delegation_referenced(struct nfs_delegation *delegation);
 int nfs4_have_delegation(struct inode *inode, fmode_t flags);
 int nfs4_check_delegation(struct inode *inode, fmode_t flags);
 bool nfs4_delegation_flush_on_close(const struct inode *inode);
+void nfs_inode_find_delegation_state_and_recover(struct inode *inode,
+		const nfs4_stateid *stateid);
 
 #endif
 

fs/nfs/dir.c

@@ -435,11 +435,11 @@ int nfs_same_file(struct dentry *dentry, struct nfs_entry *entry)
 		return 0;
 
 	nfsi = NFS_I(inode);
-	if (entry->fattr->fileid == nfsi->fileid)
-		return 1;
-	if (nfs_compare_fh(entry->fh, &nfsi->fh) == 0)
-		return 1;
-	return 0;
+	if (entry->fattr->fileid != nfsi->fileid)
+		return 0;
+	if (entry->fh->size && nfs_compare_fh(entry->fh, &nfsi->fh) != 0)
+		return 0;
+	return 1;
 }
 
 static
@@ -496,6 +496,14 @@ void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
 		return;
 	if (!(entry->fattr->valid & NFS_ATTR_FATTR_FSID))
 		return;
+	if (filename.len == 0)
+		return;
+	/* Validate that the name doesn't contain any illegal '\0' */
+	if (strnlen(filename.name, filename.len) != filename.len)
+		return;
+	/* ...or '/' */
+	if (strnchr(filename.name, filename.len, '/'))
+		return;
 	if (filename.name[0] == '.') {
 		if (filename.len == 1)
 			return;
@@ -517,6 +525,8 @@ again:
 					&entry->fattr->fsid))
 			goto out;
 		if (nfs_same_file(dentry, entry)) {
+			if (!entry->fh->size)
+				goto out;
 			nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
 			status = nfs_refresh_inode(d_inode(dentry), entry->fattr);
 			if (!status)
@@ -529,6 +539,10 @@ again:
 			goto again;
 		}
 	}
+	if (!entry->fh->size) {
+		d_lookup_done(dentry);
+		goto out;
+	}
 
 	inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr, entry->label);
 	alias = d_splice_alias(inode, dentry);

fs/nfs/direct.c

@@ -387,7 +387,7 @@ static void nfs_direct_complete(struct nfs_direct_req *dreq)
 		dreq->iocb->ki_complete(dreq->iocb, res, 0);
 	}
 
-	complete_all(&dreq->completion);
+	complete(&dreq->completion);
 
 	nfs_direct_req_release(dreq);
 }

fs/nfs/file.c

@@ -520,7 +520,9 @@ const struct address_space_operations nfs_file_aops = {
 	.invalidatepage = nfs_invalidate_page,
 	.releasepage = nfs_release_page,
 	.direct_IO = nfs_direct_IO,
+#ifdef CONFIG_MIGRATION
 	.migratepage = nfs_migrate_page,
+#endif
 	.launder_page = nfs_launder_page,
 	.is_dirty_writeback = nfs_check_dirty_writeback,
 	.error_remove_page = generic_error_remove_page,
@@ -685,11 +687,6 @@ out_noconflict:
 	goto out;
 }
 
-static int do_vfs_lock(struct file *file, struct file_lock *fl)
-{
-	return locks_lock_file_wait(file, fl);
-}
-
 static int
 do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 {
@@ -722,7 +719,7 @@ do_unlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 	if (!is_local)
 		status = NFS_PROTO(inode)->lock(filp, cmd, fl);
 	else
-		status = do_vfs_lock(filp, fl);
+		status = locks_lock_file_wait(filp, fl);
 	return status;
 }
 
@@ -747,7 +744,7 @@ do_setlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
 	if (!is_local)
 		status = NFS_PROTO(inode)->lock(filp, cmd, fl);
 	else
-		status = do_vfs_lock(filp, fl);
+		status = locks_lock_file_wait(filp, fl);
 	if (status < 0)
 		goto out;
 

fs/nfs/flexfilelayout/flexfilelayout.c

@@ -1080,7 +1080,7 @@ static int ff_layout_async_handle_error_v4(struct rpc_task *task,
 	case -NFS4ERR_BAD_STATEID:
 		if (state == NULL)
 			break;
-		nfs_remove_bad_delegation(state->inode);
+		nfs_remove_bad_delegation(state->inode, NULL);
 	case -NFS4ERR_OPENMODE:
 		if (state == NULL)
 			break;

fs/nfs/internal.h

@@ -534,12 +534,9 @@ void nfs_clear_pnfs_ds_commit_verifiers(struct pnfs_ds_commit_info *cinfo)
 }
 #endif
 
-
 #ifdef CONFIG_MIGRATION
 extern int nfs_migrate_page(struct address_space *,
 		struct page *, struct page *, enum migrate_mode);
-#else
-#define nfs_migrate_page NULL
 #endif
 
 static inline int
@@ -562,7 +559,6 @@ void nfs_init_cinfo_from_dreq(struct nfs_commit_info *cinfo,
 extern ssize_t nfs_dreq_bytes_left(struct nfs_direct_req *dreq);
 
 /* nfs4proc.c */
-extern void __nfs4_read_done_cb(struct nfs_pgio_header *);
 extern struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 			    const struct nfs_client_initdata *);
 extern int nfs40_walk_client_list(struct nfs_client *clp,
@@ -571,6 +567,9 @@ extern int nfs40_walk_client_list(struct nfs_client *clp,
 extern int nfs41_walk_client_list(struct nfs_client *clp,
 				struct nfs_client **result,
 				struct rpc_cred *cred);
+extern int nfs4_test_session_trunk(struct rpc_clnt *,
+				struct rpc_xprt *,
+				void *);
 
 static inline struct inode *nfs_igrab_and_active(struct inode *inode)
 {

fs/nfs/netns.h

@@ -29,7 +29,7 @@ struct nfs_net {
 	int cb_users[NFS4_MAX_MINOR_VERSION + 1];
 #endif
 	spinlock_t nfs_client_lock;
-	struct timespec boot_time;
+	ktime_t boot_time;
 #ifdef CONFIG_PROC_FS
 	struct proc_dir_entry *proc_nfsfs;
 #endif

fs/nfs/nfs42proc.c

@@ -443,6 +443,7 @@ int nfs42_proc_layoutstats_generic(struct nfs_server *server,
 	task = rpc_run_task(&task_setup);
 	if (IS_ERR(task))
 		return PTR_ERR(task);
+	rpc_put_task(task);
 	return 0;
 }
 

fs/nfs/nfs4_fs.h

@@ -39,6 +39,7 @@ enum nfs4_client_state {
 	NFS4CLNT_BIND_CONN_TO_SESSION,
 	NFS4CLNT_MOVED,
 	NFS4CLNT_LEASE_MOVED,
+	NFS4CLNT_DELEGATION_EXPIRED,
 };
 
 #define NFS4_RENEW_TIMEOUT		0x01
@@ -57,8 +58,11 @@ struct nfs4_minor_version_ops {
 			struct nfs_fsinfo *);
 	void	(*free_lock_state)(struct nfs_server *,
 			struct nfs4_lock_state *);
+	int	(*test_and_free_expired)(struct nfs_server *,
+			nfs4_stateid *, struct rpc_cred *);
 	struct nfs_seqid *
 		(*alloc_seqid)(struct nfs_seqid_counter *, gfp_t);
+	int	(*session_trunk)(struct rpc_clnt *, struct rpc_xprt *, void *);
 	const struct rpc_call_ops *call_sync_ops;
 	const struct nfs4_state_recovery_ops *reboot_recovery_ops;
 	const struct nfs4_state_recovery_ops *nograce_recovery_ops;
@@ -156,6 +160,7 @@ enum {
 	NFS_STATE_RECLAIM_NOGRACE,	/* OPEN stateid needs to recover state */
 	NFS_STATE_POSIX_LOCKS,		/* Posix locks are supported */
 	NFS_STATE_RECOVERY_FAILED,	/* OPEN stateid state recovery failed */
+	NFS_STATE_MAY_NOTIFY_LOCK,	/* server may CB_NOTIFY_LOCK */
 };
 
 struct nfs4_state {
@@ -203,6 +208,11 @@ struct nfs4_state_recovery_ops {
 		struct rpc_cred *);
 };
 
+struct nfs4_add_xprt_data {
+	struct nfs_client	*clp;
+	struct rpc_cred		*cred;
+};
+
 struct nfs4_state_maintenance_ops {
 	int (*sched_state_renewal)(struct nfs_client *, struct rpc_cred *, unsigned);
 	struct rpc_cred * (*get_state_renewal_cred_locked)(struct nfs_client *);
@@ -278,6 +288,8 @@ extern int nfs4_proc_get_lease_time(struct nfs_client *clp,
 		struct nfs_fsinfo *fsinfo);
 extern int nfs4_proc_layoutcommit(struct nfs4_layoutcommit_data *data,
 				  bool sync);
+extern int nfs4_detect_session_trunking(struct nfs_client *clp,
+		struct nfs41_exchange_id_res *res, struct rpc_xprt *xprt);
 
 static inline bool
 is_ds_only_client(struct nfs_client *clp)
@@ -439,7 +451,7 @@ extern void nfs4_schedule_path_down_recovery(struct nfs_client *clp);
 extern int nfs4_schedule_stateid_recovery(const struct nfs_server *, struct nfs4_state *);
 extern int nfs4_schedule_migration_recovery(const struct nfs_server *);
 extern void nfs4_schedule_lease_moved_recovery(struct nfs_client *);
-extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags);
+extern void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags, bool);
 extern void nfs41_handle_server_scope(struct nfs_client *,
 				      struct nfs41_server_scope **);
 extern void nfs4_put_lock_state(struct nfs4_lock_state *lsp);
@@ -471,6 +483,7 @@ extern struct nfs_subversion nfs_v4;
 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
 extern bool nfs4_disable_idmapping;
 extern unsigned short max_session_slots;
+extern unsigned short max_session_cb_slots;
 extern unsigned short send_implementation_id;
 extern bool recover_lost_locks;
 

fs/nfs/nfs4client.c

@@ -199,6 +199,9 @@ struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 	clp->cl_minorversion = cl_init->minorversion;
 	clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 	clp->cl_mig_gen = 1;
+#if IS_ENABLED(CONFIG_NFS_V4_1)
+	init_waitqueue_head(&clp->cl_lock_waitq);
+#endif
 	return clp;
 
 error:
@@ -562,15 +565,15 @@ out:
 /*
  * Returns true if the client IDs match
  */
-static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
+static bool nfs4_match_clientids(u64 a, u64 b)
 {
-	if (a->cl_clientid != b->cl_clientid) {
+	if (a != b) {
 		dprintk("NFS: --> %s client ID %llx does not match %llx\n",
-			__func__, a->cl_clientid, b->cl_clientid);
+			__func__, a, b);
 		return false;
 	}
 	dprintk("NFS: --> %s client ID %llx matches %llx\n",
-		__func__, a->cl_clientid, b->cl_clientid);
+		__func__, a, b);
 	return true;
 }
 
@@ -578,17 +581,15 @@ static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
  * Returns true if the server major ids match
  */
 static bool
-nfs4_check_clientid_trunking(struct nfs_client *a, struct nfs_client *b)
+nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
+				struct nfs41_server_owner *o2)
 {
-	struct nfs41_server_owner *o1 = a->cl_serverowner;
-	struct nfs41_server_owner *o2 = b->cl_serverowner;
-
 	if (o1->major_id_sz != o2->major_id_sz)
 		goto out_major_mismatch;
 	if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
 		goto out_major_mismatch;
 
-	dprintk("NFS: --> %s server owners match\n", __func__);
+	dprintk("NFS: --> %s server owner major IDs match\n", __func__);
 	return true;
 
 out_major_mismatch:
@@ -597,6 +598,100 @@ out_major_mismatch:
 	return false;
 }
 
+/*
+ * Returns true if server minor ids match
+ */
+static bool
+nfs4_check_serverowner_minor_id(struct nfs41_server_owner *o1,
+				struct nfs41_server_owner *o2)
+{
+	/* Check eir_server_owner so_minor_id */
+	if (o1->minor_id != o2->minor_id)
+		goto out_minor_mismatch;
+
+	dprintk("NFS: --> %s server owner minor IDs match\n", __func__);
+	return true;
+
+out_minor_mismatch:
+	dprintk("NFS: --> %s server owner minor IDs do not match\n", __func__);
+	return false;
+}
+
+/*
+ * Returns true if the server scopes match
+ */
+static bool
+nfs4_check_server_scope(struct nfs41_server_scope *s1,
+			struct nfs41_server_scope *s2)
+{
+	if (s1->server_scope_sz != s2->server_scope_sz)
+		goto out_scope_mismatch;
+	if (memcmp(s1->server_scope, s2->server_scope,
+		   s1->server_scope_sz) != 0)
+		goto out_scope_mismatch;
+
+	dprintk("NFS: --> %s server scopes match\n", __func__);
+	return true;
+
+out_scope_mismatch:
+	dprintk("NFS: --> %s server scopes do not match\n",
+		__func__);
+	return false;
+}
+
+/**
+ * nfs4_detect_session_trunking - Checks for session trunking.
+ *
+ * Called after a successful EXCHANGE_ID on a multi-addr connection.
+ * Upon success, add the transport.
+ *
+ * @clp:    original mount nfs_client
+ * @res:    result structure from an exchange_id using the original mount
+ *          nfs_client with a new multi_addr transport
+ *
+ * Returns zero on success, otherwise -EINVAL
+ *
+ * Note: since the exchange_id for the new multi_addr transport uses the
+ * same nfs_client from the original mount, the cl_owner_id is reused,
+ * so eir_clientowner is the same.
+ */
+int nfs4_detect_session_trunking(struct nfs_client *clp,
+				 struct nfs41_exchange_id_res *res,
+				 struct rpc_xprt *xprt)
+{
+	/* Check eir_clientid */
+	if (!nfs4_match_clientids(clp->cl_clientid, res->clientid))
+		goto out_err;
+
+	/* Check eir_server_owner so_major_id */
+	if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
+					     res->server_owner))
+		goto out_err;
+
+	/* Check eir_server_owner so_minor_id */
+	if (!nfs4_check_serverowner_minor_id(clp->cl_serverowner,
+					     res->server_owner))
+		goto out_err;
+
+	/* Check eir_server_scope */
+	if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
+		goto out_err;
+
+	/* Session trunking passed, add the xprt */
+	rpc_clnt_xprt_switch_add_xprt(clp->cl_rpcclient, xprt);
+
+	pr_info("NFS:  %s: Session trunking succeeded for %s\n",
+		clp->cl_hostname,
+		xprt->address_strings[RPC_DISPLAY_ADDR]);
+
+	return 0;
+out_err:
+	pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
+		xprt->address_strings[RPC_DISPLAY_ADDR]);
+
+	return -EINVAL;
+}
+
 /**
  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
  *
@@ -650,7 +745,7 @@ int nfs41_walk_client_list(struct nfs_client *new,
 		if (pos->cl_cons_state != NFS_CS_READY)
 			continue;
 
-		if (!nfs4_match_clientids(pos, new))
+		if (!nfs4_match_clientids(pos->cl_clientid, new->cl_clientid))
 			continue;
 
 		/*
@@ -658,7 +753,8 @@ int nfs41_walk_client_list(struct nfs_client *new,
 		 * client id trunking. In either case, we want to fall back
 		 * to using the existing nfs_client.
 		 */
-		if (!nfs4_check_clientid_trunking(pos, new))
+		if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
+						     new->cl_serverowner))
 			continue;
 
 		/* Unlike NFSv4.0, we know that NFSv4.1 always uses the

fs/nfs/nfs4session.h

@@ -9,6 +9,7 @@
 
 /* maximum number of slots to use */
 #define NFS4_DEF_SLOT_TABLE_SIZE (64U)
+#define NFS4_DEF_CB_SLOT_TABLE_SIZE (1U)
 #define NFS4_MAX_SLOT_TABLE (1024U)
 #define NFS4_NO_SLOT ((u32)-1)
 
@@ -22,6 +23,7 @@ struct nfs4_slot {
 	u32			slot_nr;
 	u32		 	seq_nr;
 	unsigned int		interrupted : 1,
+				privileged : 1,
 				seq_done : 1;
 };
 

fs/nfs/nfs4state.c

@@ -991,6 +991,8 @@ int nfs4_select_rw_stateid(struct nfs4_state *state,
 {
 	int ret;
 
+	if (!nfs4_valid_open_stateid(state))
+		return -EIO;
 	if (cred != NULL)
 		*cred = NULL;
 	ret = nfs4_copy_lock_stateid(dst, state, lockowner);
@@ -1303,6 +1305,8 @@ void nfs4_schedule_path_down_recovery(struct nfs_client *clp)
 static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_state *state)
 {
 
+	if (!nfs4_valid_open_stateid(state))
+		return 0;
 	set_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 	/* Don't recover state that expired before the reboot */
 	if (test_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags)) {
@@ -1316,6 +1320,8 @@ static int nfs4_state_mark_reclaim_reboot(struct nfs_client *clp, struct nfs4_st
 
 int nfs4_state_mark_reclaim_nograce(struct nfs_client *clp, struct nfs4_state *state)
 {
+	if (!nfs4_valid_open_stateid(state))
+		return 0;
 	set_bit(NFS_STATE_RECLAIM_NOGRACE, &state->flags);
 	clear_bit(NFS_STATE_RECLAIM_REBOOT, &state->flags);
 	set_bit(NFS_OWNER_RECLAIM_NOGRACE, &state->owner->so_flags);
@@ -1327,9 +1333,8 @@ int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_
 {
 	struct nfs_client *clp = server->nfs_client;
 
-	if (!nfs4_valid_open_stateid(state))
+	if (!nfs4_state_mark_reclaim_nograce(clp, 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);
@@ -1337,6 +1342,35 @@ int nfs4_schedule_stateid_recovery(const struct nfs_server *server, struct nfs4_
 }
 EXPORT_SYMBOL_GPL(nfs4_schedule_stateid_recovery);
 
+static struct nfs4_lock_state *
+nfs_state_find_lock_state_by_stateid(struct nfs4_state *state,
+		const nfs4_stateid *stateid)
+{
+	struct nfs4_lock_state *pos;
+
+	list_for_each_entry(pos, &state->lock_states, ls_locks) {
+		if (!test_bit(NFS_LOCK_INITIALIZED, &pos->ls_flags))
+			continue;
+		if (nfs4_stateid_match_other(&pos->ls_stateid, stateid))
+			return pos;
+	}
+	return NULL;
+}
+
+static bool nfs_state_lock_state_matches_stateid(struct nfs4_state *state,
+		const nfs4_stateid *stateid)
+{
+	bool found = false;
+
+	if (test_bit(LK_STATE_IN_USE, &state->flags)) {
+		spin_lock(&state->state_lock);
+		if (nfs_state_find_lock_state_by_stateid(state, stateid))
+			found = true;
+		spin_unlock(&state->state_lock);
+	}
+	return found;
+}
+
 void nfs_inode_find_state_and_recover(struct inode *inode,
 		const nfs4_stateid *stateid)
 {
@@ -1351,14 +1385,18 @@ void nfs_inode_find_state_and_recover(struct inode *inode,
 		state = ctx->state;
 		if (state == NULL)
 			continue;
-		if (!test_bit(NFS_DELEGATED_STATE, &state->flags))
+		if (nfs4_stateid_match_other(&state->stateid, stateid) &&
+		    nfs4_state_mark_reclaim_nograce(clp, state)) {
+			found = true;
 			continue;
-		if (!nfs4_stateid_match(&state->stateid, stateid))
-			continue;
-		nfs4_state_mark_reclaim_nograce(clp, state);
-		found = true;
+		}
+		if (nfs_state_lock_state_matches_stateid(state, stateid) &&
+		    nfs4_state_mark_reclaim_nograce(clp, state))
+			found = true;
 	}
 	spin_unlock(&inode->i_lock);
+
+	nfs_inode_find_delegation_state_and_recover(inode, stateid);
 	if (found)
 		nfs4_schedule_state_manager(clp);
 }
@@ -1498,6 +1536,9 @@ restart:
 					__func__, status);
 			case -ENOENT:
 			case -ENOMEM:
+			case -EACCES:
+			case -EROFS:
+			case -EIO:
 			case -ESTALE:
 				/* Open state on this file cannot be recovered */
 				nfs4_state_mark_recovery_failed(state, status);
@@ -1656,15 +1697,9 @@ static void nfs4_state_end_reclaim_reboot(struct nfs_client *clp)
 	put_rpccred(cred);
 }
 
-static void nfs_delegation_clear_all(struct nfs_client *clp)
-{
-	nfs_delegation_mark_reclaim(clp);
-	nfs_delegation_reap_unclaimed(clp);
-}
-
 static void nfs4_state_start_reclaim_nograce(struct nfs_client *clp)
 {
-	nfs_delegation_clear_all(clp);
+	nfs_mark_test_expired_all_delegations(clp);
 	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
 }
 
@@ -2195,7 +2230,7 @@ static void nfs41_handle_all_state_revoked(struct nfs_client *clp)
 
 static void nfs41_handle_some_state_revoked(struct nfs_client *clp)
 {
-	nfs4_state_mark_reclaim_helper(clp, nfs4_state_mark_reclaim_nograce);
+	nfs4_state_start_reclaim_nograce(clp);
 	nfs4_schedule_state_manager(clp);
 
 	dprintk("%s: state revoked on server %s\n", __func__, clp->cl_hostname);
@@ -2227,13 +2262,22 @@ static void nfs41_handle_cb_path_down(struct nfs_client *clp)
 		nfs4_schedule_state_manager(clp);
 }
 
-void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
+void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags,
+		bool recovery)
 {
 	if (!flags)
 		return;
 
 	dprintk("%s: \"%s\" (client ID %llx) flags=0x%08x\n",
 		__func__, clp->cl_hostname, clp->cl_clientid, flags);
+	/*
+	 * If we're called from the state manager thread, then assume we're
+	 * already handling the RECLAIM_NEEDED and/or STATE_REVOKED.
+	 * Those flags are expected to remain set until we're done
+	 * recovering (see RFC5661, section 18.46.3).
+	 */
+	if (recovery)
+		goto out_recovery;
 
 	if (flags & SEQ4_STATUS_RESTART_RECLAIM_NEEDED)
 		nfs41_handle_server_reboot(clp);
@@ -2246,6 +2290,7 @@ void nfs41_handle_sequence_flag_errors(struct nfs_client *clp, u32 flags)
 		nfs4_schedule_lease_moved_recovery(clp);
 	if (flags & SEQ4_STATUS_RECALLABLE_STATE_REVOKED)
 		nfs41_handle_recallable_state_revoked(clp);
+out_recovery:
 	if (flags & SEQ4_STATUS_BACKCHANNEL_FAULT)
 		nfs41_handle_backchannel_fault(clp);
 	else if (flags & (SEQ4_STATUS_CB_PATH_DOWN |
@@ -2410,6 +2455,13 @@ static void nfs4_state_manager(struct nfs_client *clp)
 			nfs4_state_end_reclaim_reboot(clp);
 		}
 
+		/* Detect expired delegations... */
+		if (test_and_clear_bit(NFS4CLNT_DELEGATION_EXPIRED, &clp->cl_state)) {
+			section = "detect expired delegations";
+			nfs_reap_expired_delegations(clp);
+			continue;
+		}
+
 		/* Now recover expired state... */
 		if (test_and_clear_bit(NFS4CLNT_RECLAIM_NOGRACE, &clp->cl_state)) {
 			section = "reclaim nograce";

fs/nfs/nfs4xdr.c

@@ -1850,7 +1850,7 @@ static void encode_create_session(struct xdr_stream *xdr,
 	*p++ = cpu_to_be32(RPC_AUTH_UNIX);			/* auth_sys */
 
 	/* authsys_parms rfc1831 */
-	*p++ = cpu_to_be32(nn->boot_time.tv_nsec);	/* stamp */
+	*p++ = cpu_to_be32(ktime_to_ns(nn->boot_time));	/* stamp */
 	p = xdr_encode_array(p, clnt->cl_nodename, clnt->cl_nodelen);
 	*p++ = cpu_to_be32(0);				/* UID */
 	*p++ = cpu_to_be32(0);				/* GID */
@@ -4725,34 +4725,37 @@ static int decode_getfattr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
 }
 
 /*
- * Decode potentially multiple layout types. Currently we only support
- * one layout driver per file system.
+ * Decode potentially multiple layout types.
  */
-static int decode_first_pnfs_layout_type(struct xdr_stream *xdr,
-					 uint32_t *layouttype)
+static int decode_pnfs_layout_types(struct xdr_stream *xdr,
+				    struct nfs_fsinfo *fsinfo)
 {
 	__be32 *p;
-	int num;
+	uint32_t i;
 
 	p = xdr_inline_decode(xdr, 4);
 	if (unlikely(!p))
 		goto out_overflow;
-	num = be32_to_cpup(p);
+	fsinfo->nlayouttypes = be32_to_cpup(p);
 
 	/* pNFS is not supported by the underlying file system */
-	if (num == 0) {
-		*layouttype = 0;
+	if (fsinfo->nlayouttypes == 0)
 		return 0;
-	}
-	if (num > 1)
-		printk(KERN_INFO "NFS: %s: Warning: Multiple pNFS layout "
-			"drivers per filesystem not supported\n", __func__);
 
 	/* Decode and set first layout type, move xdr->p past unused types */
-	p = xdr_inline_decode(xdr, num * 4);
+	p = xdr_inline_decode(xdr, fsinfo->nlayouttypes * 4);
 	if (unlikely(!p))
 		goto out_overflow;
-	*layouttype = be32_to_cpup(p);
+
+	/* If we get too many, then just cap it at the max */
+	if (fsinfo->nlayouttypes > NFS_MAX_LAYOUT_TYPES) {
+		printk(KERN_INFO "NFS: %s: Warning: Too many (%u) pNFS layout types\n",
+			__func__, fsinfo->nlayouttypes);
+		fsinfo->nlayouttypes = NFS_MAX_LAYOUT_TYPES;
+	}
+
+	for(i = 0; i < fsinfo->nlayouttypes; ++i)
+		fsinfo->layouttype[i] = be32_to_cpup(p++);
 	return 0;
 out_overflow:
 	print_overflow_msg(__func__, xdr);
@@ -4764,7 +4767,7 @@ out_overflow:
  * Note we must ensure that layouttype is set in any non-error case.
  */
 static int decode_attr_pnfstype(struct xdr_stream *xdr, uint32_t *bitmap,
-				uint32_t *layouttype)
+				struct nfs_fsinfo *fsinfo)
 {
 	int status = 0;
 
@@ -4772,10 +4775,9 @@ static int decode_attr_pnfstype(struct xdr_stream *xdr, uint32_t *bitmap,
 	if (unlikely(bitmap[1] & (FATTR4_WORD1_FS_LAYOUT_TYPES - 1U)))
 		return -EIO;
 	if (bitmap[1] & FATTR4_WORD1_FS_LAYOUT_TYPES) {
-		status = decode_first_pnfs_layout_type(xdr, layouttype);
+		status = decode_pnfs_layout_types(xdr, fsinfo);
 		bitmap[1] &= ~FATTR4_WORD1_FS_LAYOUT_TYPES;
-	} else
-		*layouttype = 0;
+	}
 	return status;
 }
 
@@ -4856,7 +4858,7 @@ static int decode_fsinfo(struct xdr_stream *xdr, struct nfs_fsinfo *fsinfo)
 	status = decode_attr_time_delta(xdr, bitmap, &fsinfo->time_delta);
 	if (status != 0)
 		goto xdr_error;
-	status = decode_attr_pnfstype(xdr, bitmap, &fsinfo->layouttype);
+	status = decode_attr_pnfstype(xdr, bitmap, fsinfo);
 	if (status != 0)
 		goto xdr_error;
 

fs/nfs/pnfs.c

@@ -30,6 +30,7 @@
 #include <linux/nfs_fs.h>
 #include <linux/nfs_page.h>
 #include <linux/module.h>
+#include <linux/sort.h>
 #include "internal.h"
 #include "pnfs.h"
 #include "iostat.h"
@@ -98,36 +99,80 @@ unset_pnfs_layoutdriver(struct nfs_server *nfss)
 	nfss->pnfs_curr_ld = NULL;
 }
 
+/*
+ * When the server sends a list of layout types, we choose one in the order
+ * given in the list below.
+ *
+ * FIXME: should this list be configurable in some fashion? module param?
+ * 	  mount option? something else?
+ */
+static const u32 ld_prefs[] = {
+	LAYOUT_SCSI,
+	LAYOUT_BLOCK_VOLUME,
+	LAYOUT_OSD2_OBJECTS,
+	LAYOUT_FLEX_FILES,
+	LAYOUT_NFSV4_1_FILES,
+	0
+};
+
+static int
+ld_cmp(const void *e1, const void *e2)
+{
+	u32 ld1 = *((u32 *)e1);
+	u32 ld2 = *((u32 *)e2);
+	int i;
+
+	for (i = 0; ld_prefs[i] != 0; i++) {
+		if (ld1 == ld_prefs[i])
+			return -1;
+
+		if (ld2 == ld_prefs[i])
+			return 1;
+	}
+	return 0;
+}
+
 /*
  * Try to set the server's pnfs module to the pnfs layout type specified by id.
  * Currently only one pNFS layout driver per filesystem is supported.
  *
- * @id layout type. Zero (illegal layout type) indicates pNFS not in use.
+ * @ids array of layout types supported by MDS.
  */
 void
 set_pnfs_layoutdriver(struct nfs_server *server, const struct nfs_fh *mntfh,
-		      u32 id)
+		      struct nfs_fsinfo *fsinfo)
 {
 	struct pnfs_layoutdriver_type *ld_type = NULL;
+	u32 id;
+	int i;
 
-	if (id == 0)
-		goto out_no_driver;
 	if (!(server->nfs_client->cl_exchange_flags &
 		 (EXCHGID4_FLAG_USE_NON_PNFS | EXCHGID4_FLAG_USE_PNFS_MDS))) {
-		printk(KERN_ERR "NFS: %s: id %u cl_exchange_flags 0x%x\n",
-			__func__, id, server->nfs_client->cl_exchange_flags);
+		printk(KERN_ERR "NFS: %s: cl_exchange_flags 0x%x\n",
+			__func__, server->nfs_client->cl_exchange_flags);
 		goto out_no_driver;
 	}
-	ld_type = find_pnfs_driver(id);
-	if (!ld_type) {
-		request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX, id);
+
+	sort(fsinfo->layouttype, fsinfo->nlayouttypes,
+		sizeof(*fsinfo->layouttype), ld_cmp, NULL);
+
+	for (i = 0; i < fsinfo->nlayouttypes; i++) {
+		id = fsinfo->layouttype[i];
 		ld_type = find_pnfs_driver(id);
 		if (!ld_type) {
-			dprintk("%s: No pNFS module found for %u.\n",
-				__func__, id);
-			goto out_no_driver;
+			request_module("%s-%u", LAYOUT_NFSV4_1_MODULE_PREFIX,
+					id);
+			ld_type = find_pnfs_driver(id);
 		}
+		if (ld_type)
+			break;
 	}
+
+	if (!ld_type) {
+		dprintk("%s: No pNFS module found!\n", __func__);
+		goto out_no_driver;
+	}
+
 	server->pnfs_curr_ld = ld_type;
 	if (ld_type->set_layoutdriver
 	    && ld_type->set_layoutdriver(server, mntfh)) {
@@ -2185,10 +2230,8 @@ static void pnfs_ld_handle_read_error(struct nfs_pgio_header *hdr)
  */
 void pnfs_ld_read_done(struct nfs_pgio_header *hdr)
 {
-	if (likely(!hdr->pnfs_error)) {
-		__nfs4_read_done_cb(hdr);
+	if (likely(!hdr->pnfs_error))
 		hdr->mds_ops->rpc_call_done(&hdr->task, hdr);
-	}
 	trace_nfs4_pnfs_read(hdr, hdr->pnfs_error);
 	if (unlikely(hdr->pnfs_error))
 		pnfs_ld_handle_read_error(hdr);

fs/nfs/pnfs.h

@@ -236,7 +236,7 @@ void pnfs_get_layout_hdr(struct pnfs_layout_hdr *lo);
 void pnfs_put_lseg(struct pnfs_layout_segment *lseg);
 void pnfs_put_lseg_locked(struct pnfs_layout_segment *lseg);
 
-void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, u32);
+void set_pnfs_layoutdriver(struct nfs_server *, const struct nfs_fh *, struct nfs_fsinfo *);
 void unset_pnfs_layoutdriver(struct nfs_server *);
 void pnfs_generic_pg_init_read(struct nfs_pageio_descriptor *, struct nfs_page *);
 int pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc);
@@ -657,7 +657,8 @@ pnfs_wait_on_layoutreturn(struct inode *ino, struct rpc_task *task)
 }
 
 static inline void set_pnfs_layoutdriver(struct nfs_server *s,
-					 const struct nfs_fh *mntfh, u32 id)
+					 const struct nfs_fh *mntfh,
+					 struct nfs_fsinfo *fsinfo)
 {
 }
 

fs/nfs/pnfs_nfs.c

@@ -690,13 +690,50 @@ static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
 		dprintk("%s: DS %s: trying address %s\n",
 			__func__, ds->ds_remotestr, da->da_remotestr);
 
-		clp = nfs4_set_ds_client(mds_srv,
-					(struct sockaddr *)&da->da_addr,
-					da->da_addrlen, IPPROTO_TCP,
-					timeo, retrans, minor_version,
-					au_flavor);
-		if (!IS_ERR(clp))
-			break;
+		if (!IS_ERR(clp) && clp->cl_mvops->session_trunk) {
+			struct xprt_create xprt_args = {
+				.ident = XPRT_TRANSPORT_TCP,
+				.net = clp->cl_net,
+				.dstaddr = (struct sockaddr *)&da->da_addr,
+				.addrlen = da->da_addrlen,
+				.servername = clp->cl_hostname,
+			};
+			struct nfs4_add_xprt_data xprtdata = {
+				.clp = clp,
+				.cred = nfs4_get_clid_cred(clp),
+			};
+			struct rpc_add_xprt_test rpcdata = {
+				.add_xprt_test = clp->cl_mvops->session_trunk,
+				.data = &xprtdata,
+			};
+
+			/**
+			* Test this address for session trunking and
+			* add as an alias
+			*/
+			rpc_clnt_add_xprt(clp->cl_rpcclient, &xprt_args,
+					  rpc_clnt_setup_test_and_add_xprt,
+					  &rpcdata);
+			if (xprtdata.cred)
+				put_rpccred(xprtdata.cred);
+		} else {
+			clp = nfs4_set_ds_client(mds_srv,
+						(struct sockaddr *)&da->da_addr,
+						da->da_addrlen, IPPROTO_TCP,
+						timeo, retrans, minor_version,
+						au_flavor);
+			if (IS_ERR(clp))
+				continue;
+
+			status = nfs4_init_ds_session(clp,
+					mds_srv->nfs_client->cl_lease_time);
+			if (status) {
+				nfs_put_client(clp);
+				clp = ERR_PTR(-EIO);
+				continue;
+			}
+
+		}
 	}
 
 	if (IS_ERR(clp)) {
@@ -704,18 +741,11 @@ static int _nfs4_pnfs_v4_ds_connect(struct nfs_server *mds_srv,
 		goto out;
 	}
 
-	status = nfs4_init_ds_session(clp, mds_srv->nfs_client->cl_lease_time);
-	if (status)
-		goto out_put;
-
 	smp_wmb();
 	ds->ds_clp = clp;
 	dprintk("%s [new] addr: %s\n", __func__, ds->ds_remotestr);
 out:
 	return status;
-out_put:
-	nfs_put_client(clp);
-	goto out;
 }
 
 /*

fs/nfs/super.c

@@ -2848,19 +2848,23 @@ out_invalid_transport_udp:
  * NFS client for backwards compatibility
  */
 unsigned int nfs_callback_set_tcpport;
+unsigned short nfs_callback_nr_threads;
 /* Default cache timeout is 10 minutes */
 unsigned int nfs_idmap_cache_timeout = 600;
 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
 bool nfs4_disable_idmapping = true;
 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
+unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
 unsigned short send_implementation_id = 1;
 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
 bool recover_lost_locks = false;
 
+EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
 EXPORT_SYMBOL_GPL(max_session_slots);
+EXPORT_SYMBOL_GPL(max_session_cb_slots);
 EXPORT_SYMBOL_GPL(send_implementation_id);
 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
 EXPORT_SYMBOL_GPL(recover_lost_locks);
@@ -2887,6 +2891,9 @@ static const struct kernel_param_ops param_ops_portnr = {
 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
 
 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
+module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
+MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
+		"assigned to the NFSv4 callback channels.");
 module_param(nfs_idmap_cache_timeout, int, 0644);
 module_param(nfs4_disable_idmapping, bool, 0644);
 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
@@ -2896,6 +2903,9 @@ MODULE_PARM_DESC(nfs4_disable_idmapping,
 module_param(max_session_slots, ushort, 0644);
 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
 		"requests the client will negotiate");
+module_param(max_session_cb_slots, ushort, 0644);
+MODULE_PARM_DESC(max_session_slots, "Maximum number of parallel NFSv4.1 "
+		"callbacks the client will process for a given server");
 module_param(send_implementation_id, ushort, 0644);
 MODULE_PARM_DESC(send_implementation_id,
 		"Send implementation ID with NFSv4.1 exchange_id");