Merge tag 'nfs-for-3.6-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull second wave of NFS client updates from Trond Myklebust:

 - Patches from Bryan to allow splitting of the NFSv2/v3/v4 code into
   separate modules.

 - Fix Oopses in the NFSv4 idmapper

 - Fix a deadlock whereby rpciod tries to allocate a new socket and ends
   up recursing into the NFS code due to memory reclaim.

 - Increase the number of permitted callback connections.

* tag 'nfs-for-3.6-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  nfs: explicitly reject LOCK_MAND flock() requests
  nfs: increase number of permitted callback connections.
  SUNRPC: return negative value in case rpcbind client creation error
  NFS: Convert v4 into a module
  NFS: Convert v3 into a module
  NFS: Convert v2 into a module
  NFS: Keep module parameters in the generic NFS client
  NFS: Split out remaining NFS v4 inode functions
  NFS: Pass super operations and xattr handlers in the nfs_subversion
  NFS: Only initialize the ACL client in the v3 case
  NFS: Create a try_mount rpc op
  NFS: Remove the NFS v4 xdev mount function
  NFS: Add version registering framework
  NFS: Fix a number of bugs in the idmapper
  nfs: skip commit in releasepage if we're freeing memory for fs-related reasons
  sunrpc: clarify comments on rpc_make_runnable
  pnfsblock: bail out partial page IO

32 files changed, 690 insertions, 390 deletions

diff --git a/fs/nfs/Kconfig b/fs/nfs/Kconfig
index 404c6a8ac39..195c1ea6151 100644
--- a/fs/nfs/Kconfig
+++ b/fs/nfs/Kconfig
@@ -30,7 +30,7 @@ config NFS_FS
 	  If unsure, say N.
 
 config NFS_V2
-	bool "NFS client support for NFS version 2"
+	tristate "NFS client support for NFS version 2"
 	depends on NFS_FS
 	default y
 	help
@@ -40,7 +40,7 @@ config NFS_V2
 	  If unsure, say Y.
 
 config NFS_V3
-	bool "NFS client support for NFS version 3"
+	tristate "NFS client support for NFS version 3"
 	depends on NFS_FS
 	default y
 	help
@@ -72,7 +72,7 @@ config NFS_V3_ACL
 	  If unsure, say N.
 
 config NFS_V4
-	bool "NFS client support for NFS version 4"
+	tristate "NFS client support for NFS version 4"
 	depends on NFS_FS
 	select SUNRPC_GSS
 	select KEYS
diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 0b96c203834..8bf3a3f6925 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -9,21 +9,22 @@ nfs-y 			:= client.o dir.o file.o getroot.o inode.o super.o \
 			   write.o namespace.o mount_clnt.o \
 			   dns_resolve.o cache_lib.o
 nfs-$(CONFIG_ROOT_NFS)	+= nfsroot.o
-nfs-$(CONFIG_NFS_V2)	+= proc.o nfs2xdr.o
-nfs-$(CONFIG_NFS_V3)	+= nfs3proc.o nfs3xdr.o
-nfs-$(CONFIG_NFS_V3_ACL)	+= nfs3acl.o
-nfs-$(CONFIG_NFS_V4)	+= nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o \
-			   nfs4super.o nfs4file.o delegation.o idmap.o \
-			   callback.o callback_xdr.o callback_proc.o \
-			   nfs4namespace.o nfs4getroot.o nfs4client.o
-nfs-$(CONFIG_NFS_V4_1)	+= pnfs.o pnfs_dev.o
+nfs-$(CONFIG_SYSCTL)	+= sysctl.o
+nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
 
-ifeq ($(CONFIG_SYSCTL), y)
-nfs-y += sysctl.o
-nfs-$(CONFIG_NFS_V4) += nfs4sysctl.o
-endif
+obj-$(CONFIG_NFS_V2) += nfs2.o
+nfs2-y := nfs2super.o proc.o nfs2xdr.o
 
-nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
+obj-$(CONFIG_NFS_V3) += nfs3.o
+nfs3-y := nfs3super.o nfs3client.o nfs3proc.o nfs3xdr.o
+nfs3-$(CONFIG_NFS_V3_ACL) += nfs3acl.o
+
+obj-$(CONFIG_NFS_V4) += nfs4.o
+nfs4-y := nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o nfs4super.o nfs4file.o \
+	  delegation.o idmap.o callback.o callback_xdr.o callback_proc.o \
+	  nfs4namespace.o nfs4getroot.o nfs4client.o
+nfs4-$(CONFIG_SYSCTL)	+= nfs4sysctl.o
+nfs4-$(CONFIG_NFS_V4_1)	+= pnfs.o pnfs_dev.o
 
 obj-$(CONFIG_PNFS_FILE_LAYOUT) += nfs_layout_nfsv41_files.o
 nfs_layout_nfsv41_files-y := nfs4filelayout.o nfs4filelayoutdev.o
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 7ae8a608956..dd392ed5f2e 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -228,6 +228,14 @@ bl_end_par_io_read(void *data, int unused)
 	schedule_work(&rdata->task.u.tk_work);
 }
 
+static bool
+bl_check_alignment(u64 offset, u32 len, unsigned long blkmask)
+{
+	if ((offset & blkmask) || (len & blkmask))
+		return false;
+	return true;
+}
+
 static enum pnfs_try_status
 bl_read_pagelist(struct nfs_read_data *rdata)
 {
@@ -244,6 +252,9 @@ bl_read_pagelist(struct nfs_read_data *rdata)
 	dprintk("%s enter nr_pages %u offset %lld count %u\n", __func__,
 	       rdata->pages.npages, f_offset, (unsigned int)rdata->args.count);
 
+	if (!bl_check_alignment(f_offset, rdata->args.count, PAGE_CACHE_MASK))
+		goto use_mds;
+
 	par = alloc_parallel(rdata);
 	if (!par)
 		goto use_mds;
@@ -552,7 +563,7 @@ bl_write_pagelist(struct nfs_write_data *wdata, int sync)
 	struct bio *bio = NULL;
 	struct pnfs_block_extent *be = NULL, *cow_read = NULL;
 	sector_t isect, last_isect = 0, extent_length = 0;
-	struct parallel_io *par;
+	struct parallel_io *par = NULL;
 	loff_t offset = wdata->args.offset;
 	size_t count = wdata->args.count;
 	struct page **pages = wdata->args.pages;
@@ -563,6 +574,10 @@ bl_write_pagelist(struct nfs_write_data *wdata, int sync)
 	    NFS_SERVER(header->inode)->pnfs_blksize >> PAGE_CACHE_SHIFT;
 
 	dprintk("%s enter, %Zu@%lld\n", __func__, count, offset);
+	/* Check for alignment first */
+	if (!bl_check_alignment(offset, count, PAGE_CACHE_MASK))
+		goto out_mds;
+
 	/* At this point, wdata->pages is a (sequential) list of nfs_pages.
 	 * We want to write each, and if there is an error set pnfs_error
 	 * to have it redone using nfs.
@@ -996,14 +1011,32 @@ bl_clear_layoutdriver(struct nfs_server *server)
 	return 0;
 }
 
+static void
+bl_pg_init_read(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+	if (!bl_check_alignment(req->wb_offset, req->wb_bytes, PAGE_CACHE_MASK))
+		nfs_pageio_reset_read_mds(pgio);
+	else
+		pnfs_generic_pg_init_read(pgio, req);
+}
+
+static void
+bl_pg_init_write(struct nfs_pageio_descriptor *pgio, struct nfs_page *req)
+{
+	if (!bl_check_alignment(req->wb_offset, req->wb_bytes, PAGE_CACHE_MASK))
+		nfs_pageio_reset_write_mds(pgio);
+	else
+		pnfs_generic_pg_init_write(pgio, req);
+}
+
 static const struct nfs_pageio_ops bl_pg_read_ops = {
-	.pg_init = pnfs_generic_pg_init_read,
+	.pg_init = bl_pg_init_read,
 	.pg_test = pnfs_generic_pg_test,
 	.pg_doio = pnfs_generic_pg_readpages,
 };
 
 static const struct nfs_pageio_ops bl_pg_write_ops = {
-	.pg_init = pnfs_generic_pg_init_write,
+	.pg_init = bl_pg_init_write,
 	.pg_test = pnfs_generic_pg_test,
 	.pg_doio = pnfs_generic_pg_writepages,
 };
diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 23ff18fe080..4c8459e5bde 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -37,31 +37,7 @@ static struct nfs_callback_data nfs_callback_info[NFS4_MAX_MINOR_VERSION + 1];
 static DEFINE_MUTEX(nfs_callback_mutex);
 static struct svc_program nfs4_callback_program;
 
-unsigned int nfs_callback_set_tcpport;
-unsigned short nfs_callback_tcpport;
 unsigned short nfs_callback_tcpport6;
-#define NFS_CALLBACK_MAXPORTNR (65535U)
-
-static int param_set_portnr(const char *val, const struct kernel_param *kp)
-{
-	unsigned long num;
-	int ret;
-
-	if (!val)
-		return -EINVAL;
-	ret = strict_strtoul(val, 0, &num);
-	if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
-		return -EINVAL;
-	*((unsigned int *)kp->arg) = num;
-	return 0;
-}
-static struct kernel_param_ops param_ops_portnr = {
-	.set = param_set_portnr,
-	.get = param_get_uint,
-};
-#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
-
-module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
 
 /*
  * This is the NFSv4 callback kernel thread.
@@ -265,6 +241,10 @@ int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt)
 		ret = -ENOMEM;
 		goto out_err;
 	}
+	/* As there is only one thread we need to over-ride the
+	 * default maximum of 80 connections
+	 */
+	serv->sv_maxconn = 1024;
 
 	ret = svc_bind(serv, net);
 	if (ret < 0) {
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index a5527c90a5a..b44d7b128b7 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -192,7 +192,7 @@ extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
 				    struct cb_process_state *cps);
 extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
 				   struct cb_process_state *cps);
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
 extern void nfs_callback_down(int minorversion);
 extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 65afa382c5e..9fc0d9dfc91 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -51,25 +51,23 @@
 #include "internal.h"
 #include "fscache.h"
 #include "pnfs.h"
+#include "nfs.h"
 #include "netns.h"
 
 #define NFSDBG_FACILITY		NFSDBG_CLIENT
 
 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
+static DEFINE_SPINLOCK(nfs_version_lock);
+static DEFINE_MUTEX(nfs_version_mutex);
+static LIST_HEAD(nfs_versions);
 
 /*
  * RPC cruft for NFS
  */
 static const struct rpc_version *nfs_version[5] = {
-#ifdef CONFIG_NFS_V2
-	[2]			= &nfs_version2,
-#endif
-#ifdef CONFIG_NFS_V3
-	[3]			= &nfs_version3,
-#endif
-#ifdef CONFIG_NFS_V4
-	[4]			= &nfs_version4,
-#endif
+	[2] = NULL,
+	[3] = NULL,
+	[4] = NULL,
 };
 
 const struct rpc_program nfs_program = {
@@ -85,21 +83,64 @@ struct rpc_stat nfs_rpcstat = {
 	.program		= &nfs_program
 };
 
+static struct nfs_subversion *find_nfs_version(unsigned int version)
+{
+	struct nfs_subversion *nfs;
+	spin_lock(&nfs_version_lock);
 
-#ifdef CONFIG_NFS_V3_ACL
-static struct rpc_stat		nfsacl_rpcstat = { &nfsacl_program };
-static const struct rpc_version *nfsacl_version[] = {
-	[3]			= &nfsacl_version3,
-};
+	list_for_each_entry(nfs, &nfs_versions, list) {
+		if (nfs->rpc_ops->version == version) {
+			spin_unlock(&nfs_version_lock);
+			return nfs;
+		}
+	};
 
-const struct rpc_program nfsacl_program = {
-	.name			= "nfsacl",
-	.number			= NFS_ACL_PROGRAM,
-	.nrvers			= ARRAY_SIZE(nfsacl_version),
-	.version		= nfsacl_version,
-	.stats			= &nfsacl_rpcstat,
-};
-#endif  /* CONFIG_NFS_V3_ACL */
+	spin_unlock(&nfs_version_lock);
+	return ERR_PTR(-EPROTONOSUPPORT);;
+}
+
+struct nfs_subversion *get_nfs_version(unsigned int version)
+{
+	struct nfs_subversion *nfs = find_nfs_version(version);
+
+	if (IS_ERR(nfs)) {
+		mutex_lock(&nfs_version_mutex);
+		request_module("nfs%d", version);
+		nfs = find_nfs_version(version);
+		mutex_unlock(&nfs_version_mutex);
+	}
+
+	if (!IS_ERR(nfs))
+		try_module_get(nfs->owner);
+	return nfs;
+}
+
+void put_nfs_version(struct nfs_subversion *nfs)
+{
+	module_put(nfs->owner);
+}
+
+void register_nfs_version(struct nfs_subversion *nfs)
+{
+	spin_lock(&nfs_version_lock);
+
+	list_add(&nfs->list, &nfs_versions);
+	nfs_version[nfs->rpc_ops->version] = nfs->rpc_vers;
+
+	spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(register_nfs_version);
+
+void unregister_nfs_version(struct nfs_subversion *nfs)
+{
+	spin_lock(&nfs_version_lock);
+
+	nfs_version[nfs->rpc_ops->version] = NULL;
+	list_del(&nfs->list);
+
+	spin_unlock(&nfs_version_lock);
+}
+EXPORT_SYMBOL_GPL(unregister_nfs_version);
 
 /*
  * Allocate a shared client record
@@ -116,7 +157,10 @@ struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 	if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 		goto error_0;
 
-	clp->rpc_ops = cl_init->rpc_ops;
+	clp->cl_nfs_mod = cl_init->nfs_mod;
+	try_module_get(clp->cl_nfs_mod->owner);
+
+	clp->rpc_ops = clp->cl_nfs_mod->rpc_ops;
 
 	atomic_set(&clp->cl_count, 1);
 	clp->cl_cons_state = NFS_CS_INITING;
@@ -145,12 +189,14 @@ struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 	return clp;
 
 error_cleanup:
+	put_nfs_version(clp->cl_nfs_mod);
 	kfree(clp);
 error_0:
 	return ERR_PTR(err);
 }
+EXPORT_SYMBOL_GPL(nfs_alloc_client);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 /* idr_remove_all is not needed as all id's are removed by nfs_put_client */
 void nfs_cleanup_cb_ident_idr(struct net *net)
 {
@@ -205,11 +251,13 @@ void nfs_free_client(struct nfs_client *clp)
 		put_rpccred(clp->cl_machine_cred);
 
 	put_net(clp->cl_net);
+	put_nfs_version(clp->cl_nfs_mod);
 	kfree(clp->cl_hostname);
 	kfree(clp);
 
 	dprintk("<-- nfs_free_client()\n");
 }
+EXPORT_SYMBOL_GPL(nfs_free_client);
 
 /*
  * Release a reference to a shared client record
@@ -324,6 +372,7 @@ int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
 	}
 	return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_sockaddr_match_ipaddr);
 #endif /* CONFIG_NFS_V4_1 */
 
 /*
@@ -362,7 +411,7 @@ static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *dat
 			continue;
 
 		/* Different NFS versions cannot share the same nfs_client */
-		if (clp->rpc_ops != data->rpc_ops)
+		if (clp->rpc_ops != data->nfs_mod->rpc_ops)
 			continue;
 
 		if (clp->cl_proto != data->proto)
@@ -390,6 +439,7 @@ int nfs_wait_client_init_complete(const struct nfs_client *clp)
 	return wait_event_killable(nfs_client_active_wq,
 			nfs_client_init_is_complete(clp));
 }
+EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
 
 /*
  * Found an existing client.  Make sure it's ready before returning.
@@ -431,9 +481,10 @@ nfs_get_client(const struct nfs_client_initdata *cl_init,
 {
 	struct nfs_client *clp, *new = NULL;
 	struct nfs_net *nn = net_generic(cl_init->net, nfs_net_id);
+	const struct nfs_rpc_ops *rpc_ops = cl_init->nfs_mod->rpc_ops;
 
 	dprintk("--> nfs_get_client(%s,v%u)\n",
-		cl_init->hostname ?: "", cl_init->rpc_ops->version);
+		cl_init->hostname ?: "", rpc_ops->version);
 
 	/* see if the client already exists */
 	do {
@@ -450,20 +501,20 @@ nfs_get_client(const struct nfs_client_initdata *cl_init,
 			list_add(&new->cl_share_link, &nn->nfs_client_list);
 			spin_unlock(&nn->nfs_client_lock);
 			new->cl_flags = cl_init->init_flags;
-			return cl_init->rpc_ops->init_client(new,
-						timeparms, ip_addr,
-						authflavour);
+			return rpc_ops->init_client(new, timeparms, ip_addr,
+						    authflavour);
 		}
 
 		spin_unlock(&nn->nfs_client_lock);
 
-		new = cl_init->rpc_ops->alloc_client(cl_init);
+		new = rpc_ops->alloc_client(cl_init);
 	} while (!IS_ERR(new));
 
 	dprintk("<-- nfs_get_client() Failed to find %s (%ld)\n",
 		cl_init->hostname ?: "", PTR_ERR(new));
 	return new;
 }
+EXPORT_SYMBOL_GPL(nfs_get_client);
 
 /*
  * Mark a server as ready or failed
@@ -474,6 +525,7 @@ void nfs_mark_client_ready(struct nfs_client *clp, int state)
 	clp->cl_cons_state = state;
 	wake_up_all(&nfs_client_active_wq);
 }
+EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
 
 /*
  * Initialise the timeout values for a connection
@@ -515,6 +567,7 @@ void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 		BUG();
 	}
 }
+EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
 
 /*
  * Create an RPC client handle
@@ -554,6 +607,7 @@ int nfs_create_rpc_client(struct nfs_client *clp,
 	clp->cl_rpcclient = clnt;
 	return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
 
 /*
  * Version 2 or 3 client destruction
@@ -606,36 +660,6 @@ static int nfs_start_lockd(struct nfs_server *server)
 }
 
 /*
- * Initialise an NFSv3 ACL client connection
- */
-#ifdef CONFIG_NFS_V3_ACL
-static void nfs_init_server_aclclient(struct nfs_server *server)
-{
-	if (server->nfs_client->rpc_ops->version != 3)
-		goto out_noacl;
-	if (server->flags & NFS_MOUNT_NOACL)
-		goto out_noacl;
-
-	server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
-	if (IS_ERR(server->client_acl))
-		goto out_noacl;
-
-	/* No errors! Assume that Sun nfsacls are supported */
-	server->caps |= NFS_CAP_ACLS;
-	return;
-
-out_noacl:
-	server->caps &= ~NFS_CAP_ACLS;
-}
-#else
-static inline void nfs_init_server_aclclient(struct nfs_server *server)
-{
-	server->flags &= ~NFS_MOUNT_NOACL;
-	server->caps &= ~NFS_CAP_ACLS;
-}
-#endif
-
-/*
  * Create a general RPC client
  */
 int nfs_init_server_rpcclient(struct nfs_server *server,
@@ -670,6 +694,7 @@ int nfs_init_server_rpcclient(struct nfs_server *server,
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
 
 /**
  * nfs_init_client - Initialise an NFS2 or NFS3 client
@@ -709,18 +734,20 @@ error:
 	dprintk("<-- nfs_init_client() = xerror %d\n", error);
 	return ERR_PTR(error);
 }
+EXPORT_SYMBOL_GPL(nfs_init_client);
 
 /*
  * Create a version 2 or 3 client
  */
 static int nfs_init_server(struct nfs_server *server,
-			   const struct nfs_parsed_mount_data *data)
+			   const struct nfs_parsed_mount_data *data,
+			   struct nfs_subversion *nfs_mod)
 {
 	struct nfs_client_initdata cl_init = {
 		.hostname = data->nfs_server.hostname,
 		.addr = (const struct sockaddr *)&data->nfs_server.address,
 		.addrlen = data->nfs_server.addrlen,
-		.rpc_ops = NULL,
+		.nfs_mod = nfs_mod,
 		.proto = data->nfs_server.protocol,
 		.net = data->net,
 	};
@@ -730,21 +757,6 @@ static int nfs_init_server(struct nfs_server *server,
 
 	dprintk("--> nfs_init_server()\n");
 
-	switch (data->version) {
-#ifdef CONFIG_NFS_V2
-	case 2:
-		cl_init.rpc_ops = &nfs_v2_clientops;
-		break;
-#endif
-#ifdef CONFIG_NFS_V3
-	case 3:
-		cl_init.rpc_ops = &nfs_v3_clientops;
-		break;
-#endif
-	default:
-		return -EPROTONOSUPPORT;
-	}
-
 	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 			data->timeo, data->retrans);
 	if (data->flags & NFS_MOUNT_NORESVPORT)
@@ -798,8 +810,6 @@ static int nfs_init_server(struct nfs_server *server,
 	server->mountd_protocol = data->mount_server.protocol;
 
 	server->namelen  = data->namlen;
-	/* Create a client RPC handle for the NFSv3 ACL management interface */
-	nfs_init_server_aclclient(server);
 	dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
 	return 0;
 
@@ -911,6 +921,7 @@ out_error:
 	dprintk("nfs_probe_fsinfo: error = %d\n", -error);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
 
 /*
  * Copy useful information when duplicating a server record
@@ -927,6 +938,7 @@ void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *sour
 	target->caps = source->caps;
 	target->options = source->options;
 }
+EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
 
 void nfs_server_insert_lists(struct nfs_server *server)
 {
@@ -940,6 +952,7 @@ void nfs_server_insert_lists(struct nfs_server *server)
 	spin_unlock(&nn->nfs_client_lock);
 
 }
+EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
 
 static void nfs_server_remove_lists(struct nfs_server *server)
 {
@@ -999,6 +1012,7 @@ struct nfs_server *nfs_alloc_server(void)
 
 	return server;
 }
+EXPORT_SYMBOL_GPL(nfs_alloc_server);
 
 /*
  * Free up a server record
@@ -1027,13 +1041,14 @@ void nfs_free_server(struct nfs_server *server)
 	nfs_release_automount_timer();
 	dprintk("<-- nfs_free_server()\n");
 }
+EXPORT_SYMBOL_GPL(nfs_free_server);
 
 /*
  * Create a version 2 or 3 volume record
  * - keyed on server and FSID
  */
-struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
-				     struct nfs_fh *mntfh)
+struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
+				     struct nfs_subversion *nfs_mod)
 {
 	struct nfs_server *server;
 	struct nfs_fattr *fattr;
@@ -1049,7 +1064,7 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
 		goto error;
 
 	/* Get a client representation */
-	error = nfs_init_server(server, data);
+	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
 	if (error < 0)
 		goto error;
 
@@ -1058,13 +1073,13 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
 	BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
 
 	/* Probe the root fh to retrieve its FSID */
-	error = nfs_probe_fsinfo(server, mntfh, fattr);
+	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
 	if (error < 0)
 		goto error;
 	if (server->nfs_client->rpc_ops->version == 3) {
 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
 			server->namelen = NFS3_MAXNAMLEN;
-		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
+		if (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
 			server->caps |= NFS_CAP_READDIRPLUS;
 	} else {
 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
@@ -1072,7 +1087,7 @@ struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
 	}
 
 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
-		error = server->nfs_client->rpc_ops->getattr(server, mntfh, fattr);
+		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr);
 		if (error < 0) {
 			dprintk("nfs_create_server: getattr error = %d\n", -error);
 			goto error;
@@ -1094,6 +1109,7 @@ error:
 	nfs_free_server(server);
 	return ERR_PTR(error);
 }
+EXPORT_SYMBOL_GPL(nfs_create_server);
 
 /*
  * Clone an NFS2, NFS3 or NFS4 server record
@@ -1133,8 +1149,6 @@ struct nfs_server *nfs_clone_server(struct nfs_server *source,
 			flavor);
 	if (error < 0)
 		goto out_free_server;
-	if (!IS_ERR(source->client_acl))
-		nfs_init_server_aclclient(server);
 
 	/* probe the filesystem info for this server filesystem */
 	error = nfs_probe_fsinfo(server, fh, fattr_fsinfo);
@@ -1165,6 +1179,7 @@ out_free_server:
 	dprintk("<-- nfs_clone_server() = error %d\n", error);
 	return ERR_PTR(error);
 }
+EXPORT_SYMBOL_GPL(nfs_clone_server);
 
 void nfs_clients_init(struct net *net)
 {
@@ -1172,7 +1187,7 @@ void nfs_clients_init(struct net *net)
 
 	INIT_LIST_HEAD(&nn->nfs_client_list);
 	INIT_LIST_HEAD(&nn->nfs_volume_list);
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 	idr_init(&nn->cb_ident_idr);
 #endif
 	spin_lock_init(&nn->nfs_client_lock);
diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h
index 1f3ccd93463..bbc6a4dba0d 100644
--- a/fs/nfs/delegation.h
+++ b/fs/nfs/delegation.h
@@ -8,7 +8,7 @@
 #ifndef FS_NFS_DELEGATION_H
 #define FS_NFS_DELEGATION_H
 
-#if defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V4)
 /*
  * NFSv4 delegation
  */
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index d49f1b9cd3f..627f108ede2 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -17,6 +17,7 @@
  *  6 Jun 1999	Cache readdir lookups in the page cache. -DaveM
  */
 
+#include <linux/module.h>
 #include <linux/time.h>
 #include <linux/errno.h>
 #include <linux/stat.h>
@@ -935,6 +936,7 @@ void nfs_force_lookup_revalidate(struct inode *dir)
 {
 	NFS_I(dir)->cache_change_attribute++;
 }
+EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate);
 
 /*
  * A check for whether or not the parent directory has changed.
@@ -1196,6 +1198,7 @@ const struct dentry_operations nfs_dentry_operations = {
 	.d_automount	= nfs_d_automount,
 	.d_release	= nfs_d_release,
 };
+EXPORT_SYMBOL_GPL(nfs_dentry_operations);
 
 struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
 {
@@ -1263,8 +1266,9 @@ out:
 	nfs_free_fhandle(fhandle);
 	return res;
 }
+EXPORT_SYMBOL_GPL(nfs_lookup);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static int nfs4_lookup_revalidate(struct dentry *, unsigned int);
 
 const struct dentry_operations nfs4_dentry_operations = {
@@ -1274,6 +1278,7 @@ const struct dentry_operations nfs4_dentry_operations = {
 	.d_automount	= nfs_d_automount,
 	.d_release	= nfs_d_release,
 };
+EXPORT_SYMBOL_GPL(nfs4_dentry_operations);
 
 static fmode_t flags_to_mode(int flags)
 {
@@ -1416,6 +1421,7 @@ no_open:
 
 	return finish_no_open(file, res);
 }
+EXPORT_SYMBOL_GPL(nfs_atomic_open);
 
 static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags)
 {
@@ -1508,6 +1514,7 @@ out_error:
 	dput(parent);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_instantiate);
 
 /*
  * Following a failed create operation, we drop the dentry rather
@@ -1536,6 +1543,7 @@ out_err:
 	d_drop(dentry);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_create);
 
 /*
  * See comments for nfs_proc_create regarding failed operations.
@@ -1563,6 +1571,7 @@ out_err:
 	d_drop(dentry);
 	return status;
 }
+EXPORT_SYMBOL_GPL(nfs_mknod);
 
 /*
  * See comments for nfs_proc_create regarding failed operations.
@@ -1586,6 +1595,7 @@ out_err:
 	d_drop(dentry);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_mkdir);
 
 static void nfs_dentry_handle_enoent(struct dentry *dentry)
 {
@@ -1609,6 +1619,7 @@ int nfs_rmdir(struct inode *dir, struct dentry *dentry)
 
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_rmdir);
 
 /*
  * Remove a file after making sure there are no pending writes,
@@ -1680,6 +1691,7 @@ int nfs_unlink(struct inode *dir, struct dentry *dentry)
 		d_rehash(dentry);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_unlink);
 
 /*
  * To create a symbolic link, most file systems instantiate a new inode,
@@ -1750,6 +1762,7 @@ int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_symlink);
 
 int
 nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
@@ -1771,6 +1784,7 @@ nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
 	}
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_link);
 
 /*
  * RENAME
@@ -1869,6 +1883,7 @@ out:
 		dput(dentry);
 	return error;
 }
+EXPORT_SYMBOL_GPL(nfs_rename);
 
 static DEFINE_SPINLOCK(nfs_access_lru_lock);
 static LIST_HEAD(nfs_access_lru_list);
@@ -1969,6 +1984,7 @@ void nfs_access_zap_cache(struct inode *inode)
 	spin_unlock(&nfs_access_lru_lock);
 	nfs_access_free_list(&head);
 }
+EXPORT_SYMBOL_GPL(nfs_access_zap_cache);
 
 static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
 {
@@ -2129,6 +2145,7 @@ int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
 {
 	return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
 }
+EXPORT_SYMBOL_GPL(nfs_may_open);
 
 int nfs_permission(struct inode *inode, int mask)
 {
@@ -2188,6 +2205,7 @@ out_notsup:
 		res = generic_permission(inode, mask);
 	goto out;
 }
+EXPORT_SYMBOL_GPL(nfs_permission);
 
 /*
  * Local variables:
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 42dce909ec7..b7b4f80968b 100644
--- a/fs/nfs/dir