Message-ID: <149382754543.30481.7918849883257680402.stgit@warthog.procyon.org.uk>
Date:   Wed, 03 May 2017 17:05:45 +0100
From:   David Howells <dhowells@...hat.com>
To:     viro@...iv.linux.org.uk
Cc:     linux-fsdevel@...r.kernel.org, dhowells@...hat.com,
        linux-nfs@...r.kernel.org, linux-kernel@...r.kernel.org,
        mszeredi@...hat.com
Subject: [PATCH 9/9] NFS: Support the mount context and fsopen()

Support the fsopen() system call in NFS, parsing the options and filling in
an nfs_parsed_mount_data struct attached to the mount_context struct.  For
example:

	mfd = fsopen("nfs4", -1, 0);
	E_write(mfd, "d warthog:/root");
	E_write(mfd, "o fsc");
	E_write(mfd, "o sync");
	E_write(mfd, "o intr");
	E_write(mfd, "o foo");

Where E_write() is a wrapper around write() that determines the string
length and, if an error occurs, will read() back the error message and
print it.

A future patch will add the actual mounting part.

Signed-off-by: David Howells <dhowells@...hat.com>
---

 fs/nfs/Makefile         |    2 
 fs/nfs/client.c         |   18 
 fs/nfs/internal.h       |  127 ++-
 fs/nfs/mount.c          | 1539 ++++++++++++++++++++++++++++++++++++++++++
 fs/nfs/namespace.c      |   75 +-
 fs/nfs/nfs3_fs.h        |    2 
 fs/nfs/nfs3client.c     |    6 
 fs/nfs/nfs3proc.c       |    1 
 fs/nfs/nfs4_fs.h        |    4 
 fs/nfs/nfs4client.c     |   80 +-
 fs/nfs/nfs4namespace.c  |  207 ++++--
 fs/nfs/nfs4proc.c       |    1 
 fs/nfs/nfs4super.c      |  184 ++---
 fs/nfs/proc.c           |    1 
 fs/nfs/super.c          | 1729 +++--------------------------------------------
 include/linux/nfs_xdr.h |    7 
 16 files changed, 2035 insertions(+), 1948 deletions(-)
 create mode 100644 fs/nfs/mount.c

diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 6abdda209642..655fd5e72e60 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -7,7 +7,7 @@ obj-$(CONFIG_NFS_FS) += nfs.o
 CFLAGS_nfstrace.o += -I$(src)
 nfs-y 			:= client.o dir.o file.o getroot.o inode.o super.o \
 			   io.o direct.o pagelist.o read.o symlink.o unlink.o \
-			   write.o namespace.o mount_clnt.o nfstrace.o
+			   write.o namespace.o mount_clnt.o nfstrace.o mount.o
 nfs-$(CONFIG_ROOT_NFS)	+= nfsroot.o
 nfs-$(CONFIG_SYSCTL)	+= sysctl.o
 nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 04d15a0045e3..a40dafacdc2d 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -652,17 +652,16 @@ 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,
-			   struct nfs_subversion *nfs_mod)
+			   const struct nfs_mount_context *data)
 {
 	struct rpc_timeout timeparms;
 	struct nfs_client_initdata cl_init = {
 		.hostname = data->nfs_server.hostname,
 		.addr = (const struct sockaddr *)&data->nfs_server.address,
 		.addrlen = data->nfs_server.addrlen,
-		.nfs_mod = nfs_mod,
+		.nfs_mod = data->nfs_mod,
 		.proto = data->nfs_server.protocol,
-		.net = data->net,
+		.net = data->mc.net_ns,
 		.timeparms = &timeparms,
 	};
 	struct nfs_client *clp;
@@ -954,8 +953,7 @@ 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(struct nfs_mount_info *mount_info,
-				     struct nfs_subversion *nfs_mod)
+struct nfs_server *nfs_create_server(struct nfs_mount_context *ctx)
 {
 	struct nfs_server *server;
 	struct nfs_fattr *fattr;
@@ -971,18 +969,18 @@ struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
 		goto error;
 
 	/* Get a client representation */
-	error = nfs_init_server(server, mount_info->parsed, nfs_mod);
+	error = nfs_init_server(server, ctx);
 	if (error < 0)
 		goto error;
 
 	/* Probe the root fh to retrieve its FSID */
-	error = nfs_probe_fsinfo(server, mount_info->mntfh, fattr);
+	error = nfs_probe_fsinfo(server, ctx->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 (!(mount_info->parsed->flags & NFS_MOUNT_NORDIRPLUS))
+		if (!(ctx->flags & NFS_MOUNT_NORDIRPLUS))
 			server->caps |= NFS_CAP_READDIRPLUS;
 	} else {
 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
@@ -990,7 +988,7 @@ struct nfs_server *nfs_create_server(struct nfs_mount_info *mount_info,
 	}
 
 	if (!(fattr->valid & NFS_ATTR_FATTR)) {
-		error = nfs_mod->rpc_ops->getattr(server, mount_info->mntfh, fattr, NULL);
+		error = ctx->nfs_mod->rpc_ops->getattr(server, ctx->mntfh, fattr, NULL);
 		if (error < 0) {
 			dprintk("nfs_create_server: getattr error = %d\n", -error);
 			goto error;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 9dc65d7ae754..8575ed77ecd9 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -6,6 +6,7 @@
 #include <linux/mount.h>
 #include <linux/security.h>
 #include <linux/crc32.h>
+#include <linux/sunrpc/addr.h>
 #include <linux/nfs_page.h>
 
 #define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
@@ -35,18 +36,6 @@ static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)
 	return 1;
 }
 
-struct nfs_clone_mount {
-	const struct super_block *sb;
-	const struct dentry *dentry;
-	struct nfs_fh *fh;
-	struct nfs_fattr *fattr;
-	char *hostname;
-	char *mnt_path;
-	struct sockaddr *addr;
-	size_t addrlen;
-	rpc_authflavor_t authflavor;
-};
-
 /*
  * Note: RFC 1813 doesn't limit the number of auth flavors that
  * a server can return, so make something up.
@@ -81,15 +70,27 @@ struct nfs_client_initdata {
 	const struct rpc_timeout *timeparms;
 };
 
+enum nfs_mount_type {
+	NFS_MOUNT_ORDINARY,
+	NFS_MOUNT_CROSS_DEV,
+	NFS4_MOUNT_REMOTE,
+	NFS4_MOUNT_REFERRAL,
+	NFS4_MOUNT_REMOTE_REFERRAL,
+};
+
 /*
  * In-kernel mount arguments
  */
-struct nfs_parsed_mount_data {
-	int			flags;
+struct nfs_mount_context {
+	struct mount_context	mc;
+	enum nfs_mount_type	mount_type : 8;
+	bool			skip_remount_option_check;
+	bool			need_mount;
+	unsigned int		flags;		/* NFS{,4}_MOUNT_* flags */
 	unsigned int		rsize, wsize;
 	unsigned int		timeo, retrans;
-	unsigned int		acregmin, acregmax,
-				acdirmin, acdirmax;
+	unsigned int		acregmin, acregmax;
+	unsigned int		acdirmin, acdirmax;
 	unsigned int		namlen;
 	unsigned int		options;
 	unsigned int		bsize;
@@ -99,10 +100,14 @@ struct nfs_parsed_mount_data {
 	unsigned int		version;
 	unsigned int		minorversion;
 	char			*fscache_uniq;
-	bool			need_mount;
+	unsigned short		protofamily;
+	unsigned short		mountfamily;
 
 	struct {
-		struct sockaddr_storage	address;
+		union {
+			struct sockaddr	address;
+			struct sockaddr_storage	_address;
+		};
 		size_t			addrlen;
 		char			*hostname;
 		u32			version;
@@ -111,16 +116,36 @@ struct nfs_parsed_mount_data {
 	} mount_server;
 
 	struct {
-		struct sockaddr_storage	address;
+		union {
+			struct sockaddr	address;
+			struct sockaddr_storage	_address;
+		};
 		size_t			addrlen;
 		char			*hostname;
 		char			*export_path;
 		int			port;
 		unsigned short		protocol;
+		unsigned short		export_path_len;
 	} nfs_server;
 
-	struct security_mnt_opts lsm_opts;
-	struct net		*net;
+	struct nfs_fh		*mntfh;
+	struct nfs_subversion	*nfs_mod;
+
+	int (*set_security)(struct super_block *, struct dentry *,
+			    struct nfs_mount_context *);
+
+	/* Information for a cloned mount.  Possibly this should be either
+	 * unioned with the information above or should be a separate
+	 * mount_context derivative.
+	 */
+	struct nfs_clone_mount {
+		struct super_block	*sb;
+		struct dentry		*dentry;
+		struct nfs_fattr	*fattr;
+		bool			cloned;
+	} clone_data;
+
+	char			buf[32];	/* Parse buffer */
 };
 
 /* mount_clnt.c */
@@ -138,14 +163,6 @@ struct nfs_mount_request {
 	struct net		*net;
 };
 
-struct nfs_mount_info {
-	int (*fill_super)(struct super_block *, struct nfs_mount_info *);
-	int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
-	struct nfs_parsed_mount_data *parsed;
-	struct nfs_clone_mount *cloned;
-	struct nfs_fh *mntfh;
-};
-
 extern int nfs_mount(struct nfs_mount_request *info);
 extern void nfs_umount(const struct nfs_mount_request *info);
 
@@ -171,13 +188,9 @@ extern struct nfs_client *nfs4_find_client_ident(struct net *, int);
 extern struct nfs_client *
 nfs4_find_client_sessionid(struct net *, const struct sockaddr *,
 				struct nfs4_sessionid *, u32);
-extern struct nfs_server *nfs_create_server(struct nfs_mount_info *,
-					struct nfs_subversion *);
-extern struct nfs_server *nfs4_create_server(
-					struct nfs_mount_info *,
-					struct nfs_subversion *);
-extern struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *,
-						      struct nfs_fh *);
+extern struct nfs_server *nfs_create_server(struct nfs_mount_context *);
+extern struct nfs_server *nfs4_create_server(struct nfs_mount_context *);
+extern struct nfs_server *nfs4_create_referral_server(struct nfs_mount_context *);
 extern int nfs4_update_server(struct nfs_server *server, const char *hostname,
 					struct sockaddr *sap, size_t salen,
 					struct net *net);
@@ -229,6 +242,11 @@ extern struct svc_version nfs4_callback_version1;
 extern struct svc_version nfs4_callback_version4;
 
 struct nfs_pageio_descriptor;
+
+/* mount.c */
+extern const char nfs_slash[];
+extern struct dentry *nfs_general_mount(struct nfs_mount_context *ctx);
+
 /* pagelist.c */
 extern int __init nfs_init_nfspagecache(void);
 extern void nfs_destroy_nfspagecache(void);
@@ -390,24 +408,13 @@ extern int nfs_wait_atomic_killable(atomic_t *p);
 /* super.c */
 extern const struct super_operations nfs_sops;
 extern struct file_system_type nfs_fs_type;
-extern struct file_system_type nfs_xdev_fs_type;
-#if IS_ENABLED(CONFIG_NFS_V4)
-extern struct file_system_type nfs4_xdev_fs_type;
-extern struct file_system_type nfs4_referral_fs_type;
-#endif
 bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
-struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *,
-			struct nfs_subversion *);
-void nfs_initialise_sb(struct super_block *);
-int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
-int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
-struct dentry *nfs_fs_mount_common(struct nfs_server *, int, const char *,
-				   struct nfs_mount_info *, struct nfs_subversion *);
-struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
-struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
-		const char *, struct nfs_mount_info *);
+struct dentry *nfs_try_mount(struct nfs_mount_context *);
+int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_context *);
+int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_context *);
+struct dentry *nfs_fs_mount_common(struct nfs_server *, struct nfs_mount_context *);
 void nfs_kill_super(struct super_block *);
-int nfs_fill_super(struct super_block *, struct nfs_mount_info *);
+int nfs_fill_super(struct super_block *, struct mount_context *);
 
 extern struct rpc_stat nfs_rpcstat;
 
@@ -458,14 +465,13 @@ extern void nfs_read_prepare(struct rpc_task *task, void *calldata);
 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 
 /* super.c */
-int nfs_clone_super(struct super_block *, struct nfs_mount_info *);
 void nfs_umount_begin(struct super_block *);
 int  nfs_statfs(struct dentry *, struct kstatfs *);
 int  nfs_show_options(struct seq_file *, struct dentry *);
 int  nfs_show_devname(struct seq_file *, struct dentry *);
 int  nfs_show_path(struct seq_file *, struct dentry *);
 int  nfs_show_stats(struct seq_file *, struct dentry *);
-int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
+int nfs_remount(struct super_block *sb, struct mount_context *mc);
 
 /* write.c */
 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
@@ -765,3 +771,16 @@ static inline bool nfs_error_is_fatal(int err)
 		return false;
 	}
 }
+
+/*
+ * Select between a default port value and a user-specified port value.
+ * If a zero value is set, then autobind will be used.
+ */
+static inline void nfs_set_port(struct sockaddr *sap, int *port,
+				const unsigned short default_port)
+{
+	if (*port == NFS_UNSPEC_PORT)
+		*port = default_port;
+
+	rpc_set_port(sap, *port);
+}
diff --git a/fs/nfs/mount.c b/fs/nfs/mount.c
new file mode 100644
index 000000000000..4716bb0d0fd2
--- /dev/null
+++ b/fs/nfs/mount.c
@@ -0,0 +1,1539 @@
+/* NFS mount handling.
+ *
+ * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@...hat.com)
+ *
+ * Split from fs/nfs/super.c:
+ *
+ *  Copyright (C) 1992  Rick Sladkey
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/parser.h>
+#include <linux/nfs_fs.h>
+#include <linux/nfs_mount.h>
+#include <linux/nfs4_mount.h>
+#include "nfs.h"
+#include "internal.h"
+
+#define NFSDBG_FACILITY		NFSDBG_VFS
+
+#if IS_ENABLED(CONFIG_NFS_V3)
+#define NFS_DEFAULT_VERSION 3
+#else
+#define NFS_DEFAULT_VERSION 2
+#endif
+
+enum {
+	/* Mount options that take no arguments */
+	Opt_soft, Opt_hard,
+	Opt_posix, Opt_noposix,
+	Opt_cto, Opt_nocto,
+	Opt_ac, Opt_noac,
+	Opt_lock, Opt_nolock,
+	Opt_udp, Opt_tcp, Opt_rdma,
+	Opt_acl, Opt_noacl,
+	Opt_rdirplus, Opt_nordirplus,
+	Opt_sharecache, Opt_nosharecache,
+	Opt_resvport, Opt_noresvport,
+	Opt_fscache, Opt_nofscache,
+	Opt_migration, Opt_nomigration,
+
+	/* Mount options that take integer arguments */
+	Opt_port,
+	Opt_rsize, Opt_wsize, Opt_bsize,
+	Opt_timeo, Opt_retrans,
+	Opt_acregmin, Opt_acregmax,
+	Opt_acdirmin, Opt_acdirmax,
+	Opt_actimeo,
+	Opt_namelen,
+	Opt_mountport,
+	Opt_mountvers,
+	Opt_minorversion,
+
+	/* Mount options that take string arguments */
+	Opt_nfsvers,
+	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
+	Opt_addr, Opt_mountaddr, Opt_clientaddr,
+	Opt_lookupcache,
+	Opt_fscache_uniq,
+	Opt_local_lock,
+
+	/* Special mount options */
+	Opt_userspace, Opt_deprecated, Opt_sloppy,
+
+	Opt_err
+};
+
+static const match_table_t nfs_mount_option_tokens = {
+	{ Opt_userspace, "bg" },
+	{ Opt_userspace, "fg" },
+	{ Opt_userspace, "retry=%s" },
+
+	{ Opt_sloppy, "sloppy" },
+
+	{ Opt_soft, "soft" },
+	{ Opt_hard, "hard" },
+	{ Opt_deprecated, "intr" },
+	{ Opt_deprecated, "nointr" },
+	{ Opt_posix, "posix" },
+	{ Opt_noposix, "noposix" },
+	{ Opt_cto, "cto" },
+	{ Opt_nocto, "nocto" },
+	{ Opt_ac, "ac" },
+	{ Opt_noac, "noac" },
+	{ Opt_lock, "lock" },
+	{ Opt_nolock, "nolock" },
+	{ Opt_udp, "udp" },
+	{ Opt_tcp, "tcp" },
+	{ Opt_rdma, "rdma" },
+	{ Opt_acl, "acl" },
+	{ Opt_noacl, "noacl" },
+	{ Opt_rdirplus, "rdirplus" },
+	{ Opt_nordirplus, "nordirplus" },
+	{ Opt_sharecache, "sharecache" },
+	{ Opt_nosharecache, "nosharecache" },
+	{ Opt_resvport, "resvport" },
+	{ Opt_noresvport, "noresvport" },
+	{ Opt_fscache, "fsc" },
+	{ Opt_nofscache, "nofsc" },
+	{ Opt_migration, "migration" },
+	{ Opt_nomigration, "nomigration" },
+
+	{ Opt_port, "port=%s" },
+	{ Opt_rsize, "rsize=%s" },
+	{ Opt_wsize, "wsize=%s" },
+	{ Opt_bsize, "bsize=%s" },
+	{ Opt_timeo, "timeo=%s" },
+	{ Opt_retrans, "retrans=%s" },
+	{ Opt_acregmin, "acregmin=%s" },
+	{ Opt_acregmax, "acregmax=%s" },
+	{ Opt_acdirmin, "acdirmin=%s" },
+	{ Opt_acdirmax, "acdirmax=%s" },
+	{ Opt_actimeo, "actimeo=%s" },
+	{ Opt_namelen, "namlen=%s" },
+	{ Opt_mountport, "mountport=%s" },
+	{ Opt_mountvers, "mountvers=%s" },
+	{ Opt_minorversion, "minorversion=%s" },
+
+	{ Opt_nfsvers, "nfsvers=%s" },
+	{ Opt_nfsvers, "vers=%s" },
+
+	{ Opt_sec, "sec=%s" },
+	{ Opt_proto, "proto=%s" },
+	{ Opt_mountproto, "mountproto=%s" },
+	{ Opt_addr, "addr=%s" },
+	{ Opt_clientaddr, "clientaddr=%s" },
+	{ Opt_mounthost, "mounthost=%s" },
+	{ Opt_mountaddr, "mountaddr=%s" },
+
+	{ Opt_lookupcache, "lookupcache=%s" },
+	{ Opt_fscache_uniq, "fsc=%s" },
+	{ Opt_local_lock, "local_lock=%s" },
+
+	/* The following needs to be listed after all other options */
+	{ Opt_nfsvers, "v%s" },
+
+	{ Opt_err, NULL }
+};
+
+enum {
+	Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
+	Opt_xprt_rdma6,
+
+	Opt_xprt_err
+};
+
+static const match_table_t nfs_xprt_protocol_tokens = {
+	{ Opt_xprt_udp, "udp" },
+	{ Opt_xprt_udp6, "udp6" },
+	{ Opt_xprt_tcp, "tcp" },
+	{ Opt_xprt_tcp6, "tcp6" },
+	{ Opt_xprt_rdma, "rdma" },
+	{ Opt_xprt_rdma6, "rdma6" },
+
+	{ Opt_xprt_err, NULL }
+};
+
+enum {
+	Opt_sec_none, Opt_sec_sys,
+	Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
+	Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
+	Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
+
+	Opt_sec_err
+};
+
+static const match_table_t nfs_secflavor_tokens = {
+	{ Opt_sec_none, "none" },
+	{ Opt_sec_none, "null" },
+	{ Opt_sec_sys, "sys" },
+
+	{ Opt_sec_krb5, "krb5" },
+	{ Opt_sec_krb5i, "krb5i" },
+	{ Opt_sec_krb5p, "krb5p" },
+
+	{ Opt_sec_lkey, "lkey" },
+	{ Opt_sec_lkeyi, "lkeyi" },
+	{ Opt_sec_lkeyp, "lkeyp" },
+
+	{ Opt_sec_spkm, "spkm3" },
+	{ Opt_sec_spkmi, "spkm3i" },
+	{ Opt_sec_spkmp, "spkm3p" },
+
+	{ Opt_sec_err, NULL }
+};
+
+enum {
+	Opt_lookupcache_all, Opt_lookupcache_positive,
+	Opt_lookupcache_none,
+
+	Opt_lookupcache_err
+};
+
+static const match_table_t nfs_lookupcache_tokens = {
+	{ Opt_lookupcache_all, "all" },
+	{ Opt_lookupcache_positive, "pos" },
+	{ Opt_lookupcache_positive, "positive" },
+	{ Opt_lookupcache_none, "none" },
+
+	{ Opt_lookupcache_err, NULL }
+};
+
+enum {
+	Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
+	Opt_local_lock_none,
+
+	Opt_local_lock_err
+};
+
+static const match_table_t nfs_local_lock_tokens = {
+	{ Opt_local_lock_all, "all" },
+	{ Opt_local_lock_flock, "flock" },
+	{ Opt_local_lock_posix, "posix" },
+	{ Opt_local_lock_none, "none" },
+
+	{ Opt_local_lock_err, NULL }
+};
+
+enum {
+	Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
+	Opt_vers_4_1, Opt_vers_4_2,
+
+	Opt_vers_err
+};
+
+static const match_table_t nfs_vers_tokens = {
+	{ Opt_vers_2, "2" },
+	{ Opt_vers_3, "3" },
+	{ Opt_vers_4, "4" },
+	{ Opt_vers_4_0, "4.0" },
+	{ Opt_vers_4_1, "4.1" },
+	{ Opt_vers_4_2, "4.2" },
+
+	{ Opt_vers_err, NULL }
+};
+
+const char nfs_slash[] = "/";
+EXPORT_SYMBOL_GPL(nfs_slash);
+
+/*
+ * Sanity-check a server address provided by the mount command.
+ *
+ * Address family must be initialized, and address must not be
+ * the ANY address for that family.
+ */
+static int nfs_verify_server_address(struct sockaddr *addr)
+{
+	switch (addr->sa_family) {
+	case AF_INET: {
+		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
+		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
+	}
+	case AF_INET6: {
+		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
+		return !ipv6_addr_any(sa);
+	}
+	}
+
+	dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
+	return 0;
+}
+
+/*
+ * Sanity check the NFS transport protocol.
+ *
+ */
+static void nfs_validate_transport_protocol(struct nfs_mount_context *mnt)
+{
+	switch (mnt->nfs_server.protocol) {
+	case XPRT_TRANSPORT_UDP:
+	case XPRT_TRANSPORT_TCP:
+	case XPRT_TRANSPORT_RDMA:
+		break;
+	default:
+		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+	}
+}
+
+/*
+ * For text based NFSv2/v3 mounts, the mount protocol transport default
+ * settings should depend upon the specified NFS transport.
+ */
+static void nfs_set_mount_transport_protocol(struct nfs_mount_context *mnt)
+{
+	nfs_validate_transport_protocol(mnt);
+
+	if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
+	    mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
+			return;
+	switch (mnt->nfs_server.protocol) {
+	case XPRT_TRANSPORT_UDP:
+		mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
+		break;
+	case XPRT_TRANSPORT_TCP:
+	case XPRT_TRANSPORT_RDMA:
+		mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
+	}
+}
+
+/*
+ * Add 'flavor' to 'auth_info' if not already present.
+ * Returns true if 'flavor' ends up in the list, false otherwise
+ */
+static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
+			      rpc_authflavor_t flavor)
+{
+	unsigned int i;
+	unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
+
+	/* make sure this flavor isn't already in the list */
+	for (i = 0; i < auth_info->flavor_len; i++) {
+		if (flavor == auth_info->flavors[i])
+			return true;
+	}
+
+	if (auth_info->flavor_len + 1 >= max_flavor_len) {
+		dfprintk(MOUNT, "NFS: too many sec= flavors\n");
+		return false;
+	}
+
+	auth_info->flavors[auth_info->flavor_len++] = flavor;
+	return true;
+}
+
+/*
+ * Parse the value of the 'sec=' option.
+ */
+static int nfs_parse_security_flavors(char *value,
+				      struct nfs_mount_context *mnt)
+{
+	substring_t args[MAX_OPT_ARGS];
+	rpc_authflavor_t pseudoflavor;
+	char *p;
+
+	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
+
+	while ((p = strsep(&value, ":")) != NULL) {
+		switch (match_token(p, nfs_secflavor_tokens, args)) {
+		case Opt_sec_none:
+			pseudoflavor = RPC_AUTH_NULL;
+			break;
+		case Opt_sec_sys:
+			pseudoflavor = RPC_AUTH_UNIX;
+			break;
+		case Opt_sec_krb5:
+			pseudoflavor = RPC_AUTH_GSS_KRB5;
+			break;
+		case Opt_sec_krb5i:
+			pseudoflavor = RPC_AUTH_GSS_KRB5I;
+			break;
+		case Opt_sec_krb5p:
+			pseudoflavor = RPC_AUTH_GSS_KRB5P;
+			break;
+		case Opt_sec_lkey:
+			pseudoflavor = RPC_AUTH_GSS_LKEY;
+			break;
+		case Opt_sec_lkeyi:
+			pseudoflavor = RPC_AUTH_GSS_LKEYI;
+			break;
+		case Opt_sec_lkeyp:
+			pseudoflavor = RPC_AUTH_GSS_LKEYP;
+			break;
+		case Opt_sec_spkm:
+			pseudoflavor = RPC_AUTH_GSS_SPKM;
+			break;
+		case Opt_sec_spkmi:
+			pseudoflavor = RPC_AUTH_GSS_SPKMI;
+			break;
+		case Opt_sec_spkmp:
+			pseudoflavor = RPC_AUTH_GSS_SPKMP;
+			break;
+		default:
+			dfprintk(MOUNT,
+				 "NFS: sec= option '%s' not recognized\n", p);
+			return 0;
+		}
+
+		if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
+			return 0;
+	}
+
+	return 1;
+}
+
+static int nfs_parse_version_string(char *string,
+				    struct nfs_mount_context *mnt,
+				    substring_t *args)
+{
+	mnt->flags &= ~NFS_MOUNT_VER3;
+	switch (match_token(string, nfs_vers_tokens, args)) {
+	case Opt_vers_2:
+		mnt->version = 2;
+		break;
+	case Opt_vers_3:
+		mnt->flags |= NFS_MOUNT_VER3;
+		mnt->version = 3;
+		break;
+	case Opt_vers_4:
+		/* Backward compatibility option. In future,
+		 * the mount program should always supply
+		 * a NFSv4 minor version number.
+		 */
+		mnt->version = 4;
+		break;
+	case Opt_vers_4_0:
+		mnt->version = 4;
+		mnt->minorversion = 0;
+		break;
+	case Opt_vers_4_1:
+		mnt->version = 4;
+		mnt->minorversion = 1;
+		break;
+	case Opt_vers_4_2:
+		mnt->version = 4;
+		mnt->minorversion = 2;
+		break;
+	default:
+		return 0;
+	}
+	return 1;
+}
+
+static int nfs_get_option_str(substring_t args[], char **option)
+{
+	kfree(*option);
+	*option = match_strdup(args);
+	return !*option;
+}
+
+static int nfs_get_option_ui(struct nfs_mount_context *mc,
+			     substring_t args[], unsigned int *option)
+{
+	match_strlcpy(mc->buf, args, sizeof(mc->buf));
+	return kstrtouint(mc->buf, 10, option);
+}
+
+static int nfs_get_option_ui_bound(struct nfs_mount_context *mc,
+				   substring_t args[], unsigned int *option,
+				   unsigned int l_bound, unsigned u_bound)
+{
+	int ret;
+
+	match_strlcpy(mc->buf, args, sizeof(mc->buf));
+	ret = kstrtouint(mc->buf, 10, option);
+	if (ret < 0)
+		return ret;
+	if (*option < l_bound || *option > u_bound)
+		return -ERANGE;
+	return 0;
+}
+
+/*
+ * Split mc->device into "hostname:export_path".
+ *
+ * The leftmost colon demarks the split between the server's hostname
+ * and the export path.  If the hostname starts with a left square
+ * bracket, then it may contain colons.
+ *
+ * Note: caller frees hostname and export path, even on error.
+ */
+static int nfs_parse_devname(struct nfs_mount_context *ctx,
+			     size_t maxnamlen, size_t maxpathlen)
+{
+	char *dev_name = ctx->mc.device;
+	size_t len;
+	char *end;
+
+	/* Is the host name protected with square brakcets? */
+	if (*dev_name == '[') {
+		end = strchr(++dev_name, ']');
+		if (end == NULL || end[1] != ':')
+			goto out_bad_devname;
+
+		len = end - dev_name;
+		end++;
+	} else {
+		char *comma;
+
+		end = strchr(dev_name, ':');
+		if (end == NULL)
+			goto out_bad_devname;
+		len = end - dev_name;
+
+		/* kill possible hostname list: not supported */
+		comma = strchr(dev_name, ',');
+		if (comma != NULL && comma < end)
+			*comma = 0;
+	}
+
+	if (len > maxnamlen)
+		goto out_hostname;
+
+	/* N.B. caller will free nfs_server.hostname in all cases */
+	ctx->nfs_server.hostname = kstrcreate(dev_name, len, GFP_KERNEL);
+	if (!ctx->nfs_server.hostname)
+		goto out_nomem;
+	len = strlen(++end);
+	if (len > maxpathlen)
+		goto out_path;
+	ctx->nfs_server.export_path = kstrcreate(end, len, GFP_KERNEL);
+	if (!ctx->nfs_server.export_path)
+		goto out_nomem;
+
+	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
+	return 0;
+
+out_bad_devname:
+	ctx->mc.error = "NFS: device name not in host:path format";
+	return -EINVAL;
+out_nomem:
+	ctx->mc.error = "NFS: not enough memory to parse device name";
+	return -ENOMEM;
+out_hostname:
+	ctx->mc.error = "NFS: server hostname too long";
+	return -ENAMETOOLONG;
+out_path:
+	ctx->mc.error = "NFS: export pathname too long";
+	return -ENAMETOOLONG;
+}
+
+/*
+ * Parse monolithic NFS2/NFS3 mount data
+ * - fills in the mount root filehandle
+ *
+ * For option strings, user space handles the following behaviors:
+ *
+ * + DNS: mapping server host name to IP address ("addr=" option)
+ *
+ * + failure mode: how to behave if a mount request can't be handled
+ *   immediately ("fg/bg" option)
+ *
+ * + retry: how often to retry a mount request ("retry=" option)
+ *
+ * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
+ *   mountproto=tcp after mountproto=udp, and so on
+ */
+static int nfs23_monolithic_mount_data(struct mount_context *mc,
+				       struct nfs_mount_data *data)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+	struct nfs_fh *mntfh = ctx->mntfh;
+	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
+	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
+	int ret;
+
+	if (data == NULL)
+		goto out_no_data;
+
+	ctx->version = NFS_DEFAULT_VERSION;
+	switch (data->version) {
+	case 1:
+		data->namlen = 0;
+	case 2:
+		data->bsize = 0;
+	case 3:
+		if (data->flags & NFS_MOUNT_VER3)
+			goto out_no_v3;
+		data->root.size = NFS2_FHSIZE;
+		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
+		/* Turn off security negotiation */
+		extra_flags |= NFS_MOUNT_SECFLAVOUR;
+	case 4:
+		if (data->flags & NFS_MOUNT_SECFLAVOUR)
+			goto out_no_sec;
+	case 5:
+		memset(data->context, 0, sizeof(data->context));
+	case 6:
+		if (data->flags & NFS_MOUNT_VER3) {
+			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
+				goto out_invalid_fh;
+			mntfh->size = data->root.size;
+			ctx->version = 3;
+		} else {
+			mntfh->size = NFS2_FHSIZE;
+			ctx->version = 2;
+		}
+
+		memcpy(mntfh->data, data->root.data, mntfh->size);
+		if (mntfh->size < sizeof(mntfh->data))
+			memset(mntfh->data + mntfh->size, 0,
+			       sizeof(mntfh->data) - mntfh->size);
+
+		/*
+		 * Translate to nfs_mount_context, which nfs_fill_super
+		 * can deal with.
+		 */
+		ctx->flags	= data->flags & NFS_MOUNT_FLAGMASK;
+		ctx->flags	|= extra_flags;
+		ctx->rsize	= data->rsize;
+		ctx->wsize	= data->wsize;
+		ctx->timeo	= data->timeo;
+		ctx->retrans	= data->retrans;
+		ctx->acregmin	= data->acregmin;
+		ctx->acregmax	= data->acregmax;
+		ctx->acdirmin	= data->acdirmin;
+		ctx->acdirmax	= data->acdirmax;
+		ctx->need_mount	= false;
+
+		memcpy(sap, &data->addr, sizeof(data->addr));
+		ctx->nfs_server.addrlen = sizeof(data->addr);
+		ctx->nfs_server.port = ntohs(data->addr.sin_port);
+		if (!nfs_verify_server_address(sap))
+			goto out_no_address;
+
+		if (!(data->flags & NFS_MOUNT_TCP))
+			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
+		/* N.B. caller will free nfs_server.hostname in all cases */
+		ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
+		if (!ctx->nfs_server.hostname)
+			goto out_nomem;
+
+		ctx->namlen	= data->namlen;
+		ctx->bsize	= data->bsize;
+
+		if (data->flags & NFS_MOUNT_SECFLAVOUR)
+			ctx->selected_flavor = data->pseudoflavor;
+		else
+			ctx->selected_flavor = RPC_AUTH_UNIX;
+
+		if (!(data->flags & NFS_MOUNT_NONLM))
+			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
+					 NFS_MOUNT_LOCAL_FCNTL);
+		else
+			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
+					NFS_MOUNT_LOCAL_FCNTL);
+
+		/* The legacy version 6 binary mount data from userspace has a
+		 * field used only to transport selinux information into the
+		 * the kernel.  To continue to support that functionality we
+		 * have a touch of selinux knowledge here in the NFS code. The
+		 * userspace code converted context=blah to just blah so we are
+		 * converting back to the full string selinux understands.
+		 */
+		if (data->context[0]){
+#ifdef CONFIG_SECURITY_SELINUX
+			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
+			if (!opts_str)
+				return -ENOMEM;
+			strcpy(opts_str, "context=");
+			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
+			strcat(opts_str, &data->context[0]);
+			ret = vfs_mount_option(mc, opts_str);
+			kfree(opts_str);
+			if (ret)
+				return ret;
+#else
+			return -EINVAL;
+#endif
+		}
+
+		break;
+	default:
+		return generic_monolithic_mount_data(mc, data);
+	}
+
+	ctx->skip_remount_option_check = true;
+	return 0;
+
+out_no_data:
+	if (mc->ms_flags & MS_REMOUNT) {
+		ctx->skip_remount_option_check = true;
+		return 0;
+	}
+	mc->error = "NFS: mount program didn't pass any mount data";
+	return -EINVAL;
+
+out_no_v3:
+	mc->error = "NFS: nfs_mount_data version does not support v3";
+	return -EINVAL;
+
+out_no_sec:
+	mc->error = "NFS: nfs_mount_data version supports only AUTH_SYS";
+	return -EINVAL;
+
+out_nomem:
+	dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
+	return -ENOMEM;
+
+out_no_address:
+	mc->error = "NFS: mount program didn't pass remote address";
+	return -EINVAL;
+
+out_invalid_fh:
+	mc->error = "NFS: invalid root filehandle";
+	return -EINVAL;
+}
+
+/*
+ * Validate NFSv4 mount options
+ */
+static int nfs4_monolithic_mount_data(struct mount_context *mc,
+				      struct nfs4_mount_data *data)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
+	char *c;
+
+	if (data == NULL)
+		goto out_no_data;
+
+	ctx->version = 4;
+
+	switch (data->version) {
+	case 1:
+		if (data->host_addrlen > sizeof(ctx->nfs_server.address))
+			goto out_no_address;
+		if (data->host_addrlen == 0)
+			goto out_no_address;
+		ctx->nfs_server.addrlen = data->host_addrlen;
+		if (copy_from_user(sap, data->host_addr, data->host_addrlen))
+			return -EFAULT;
+		if (!nfs_verify_server_address(sap))
+			goto out_no_address;
+		ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
+
+		if (data->auth_flavourlen) {
+			rpc_authflavor_t pseudoflavor;
+			if (data->auth_flavourlen > 1)
+				goto out_inval_auth;
+			if (copy_from_user(&pseudoflavor,
+					   data->auth_flavours,
+					   sizeof(pseudoflavor)))
+				return -EFAULT;
+			ctx->selected_flavor = pseudoflavor;
+		} else
+			ctx->selected_flavor = RPC_AUTH_UNIX;
+
+		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
+		if (IS_ERR(c))
+			return PTR_ERR(c);
+		ctx->nfs_server.hostname = c;
+
+		c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
+		if (IS_ERR(c))
+			return PTR_ERR(c);
+		ctx->nfs_server.export_path = c;
+		dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
+
+		c = strndup_user(data->client_addr.data, 16);
+		if (IS_ERR(c))
+			return PTR_ERR(c);
+		ctx->client_address = c;
+
+		/*
+		 * Translate to nfs_mount_context, which nfs4_fill_super
+		 * can deal with.
+		 */
+
+		ctx->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
+		ctx->rsize	= data->rsize;
+		ctx->wsize	= data->wsize;
+		ctx->timeo	= data->timeo;
+		ctx->retrans	= data->retrans;
+		ctx->acregmin	= data->acregmin;
+		ctx->acregmax	= data->acregmax;
+		ctx->acdirmin	= data->acdirmin;
+		ctx->acdirmax	= data->acdirmax;
+		ctx->nfs_server.protocol = data->proto;
+		nfs_validate_transport_protocol(ctx);
+		if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
+			goto out_invalid_transport_udp;
+
+		break;
+	default:
+		return generic_monolithic_mount_data(mc, data);
+	}
+
+	ctx->skip_remount_option_check = true;
+	return 0;
+
+out_no_data:
+	if (mc->ms_flags & MS_REMOUNT) {
+		ctx->skip_remount_option_check = true;
+		return 0;
+	}
+	mc->error = "NFS4: mount program didn't pass any mount data";
+	return -EINVAL;
+
+out_inval_auth:
+	mc->error = "NFS4: Invalid number of RPC auth flavours";
+	return -EINVAL;
+
+out_no_address:
+	mc->error = "NFS4: mount program didn't pass remote address";
+	return -EINVAL;
+
+out_invalid_transport_udp:
+	mc->error = "NFSv4: Unsupported transport protocol udp";
+	return -EINVAL;
+}
+
+/*
+ * Parse a monolithic block of data from sys_mount().
+ */
+static int nfs_monolithic_mount_data(struct mount_context *mc, void *data)
+{
+	if (mc->fs_type == &nfs_fs_type)
+		return nfs23_monolithic_mount_data(mc, data);
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+	if (mc->fs_type == &nfs4_fs_type)
+		return nfs4_monolithic_mount_data(mc, data);
+#endif
+
+	mc->error = "NFS: Unsupported monolithic data version";
+	return -EINVAL;
+}
+
+/*
+ * Parse a single mount option in "key[=val]" form.
+ */
+static int nfs_mount_ctx_option(struct mount_context *mc, char *p)
+{
+	struct nfs_mount_context *mnt =
+		container_of(mc, struct nfs_mount_context, mc);
+	substring_t args[MAX_OPT_ARGS];
+	char *string;
+	int rc = 0, token;
+
+	dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
+
+	token = match_token(p, nfs_mount_option_tokens, args);
+	switch (token) {
+		/*
+		 * boolean options:  foo/nofoo
+		 */
+	case Opt_soft:
+		mnt->flags |= NFS_MOUNT_SOFT;
+		break;
+	case Opt_hard:
+		mnt->flags &= ~NFS_MOUNT_SOFT;
+		break;
+	case Opt_posix:
+		mnt->flags |= NFS_MOUNT_POSIX;
+		break;
+	case Opt_noposix:
+		mnt->flags &= ~NFS_MOUNT_POSIX;
+		break;
+	case Opt_cto:
+		mnt->flags &= ~NFS_MOUNT_NOCTO;
+		break;
+	case Opt_nocto:
+		mnt->flags |= NFS_MOUNT_NOCTO;
+		break;
+	case Opt_ac:
+		mnt->flags &= ~NFS_MOUNT_NOAC;
+		break;
+	case Opt_noac:
+		mnt->flags |= NFS_MOUNT_NOAC;
+		break;
+	case Opt_lock:
+		mnt->flags &= ~NFS_MOUNT_NONLM;
+		mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
+		break;
+	case Opt_nolock:
+		mnt->flags |= NFS_MOUNT_NONLM;
+		mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
+		break;
+	case Opt_udp:
+		mnt->flags &= ~NFS_MOUNT_TCP;
+		mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
+		break;
+	case Opt_tcp:
+		mnt->flags |= NFS_MOUNT_TCP;
+		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+		break;
+	case Opt_rdma:
+		mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
+		mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
+		xprt_load_transport(p);
+		break;
+	case Opt_acl:
+		mnt->flags &= ~NFS_MOUNT_NOACL;
+		break;
+	case Opt_noacl:
+		mnt->flags |= NFS_MOUNT_NOACL;
+		break;
+	case Opt_rdirplus:
+		mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
+		break;
+	case Opt_nordirplus:
+		mnt->flags |= NFS_MOUNT_NORDIRPLUS;
+		break;
+	case Opt_sharecache:
+		mnt->flags &= ~NFS_MOUNT_UNSHARED;
+		break;
+	case Opt_nosharecache:
+		mnt->flags |= NFS_MOUNT_UNSHARED;
+		break;
+	case Opt_resvport:
+		mnt->flags &= ~NFS_MOUNT_NORESVPORT;
+		break;
+	case Opt_noresvport:
+		mnt->flags |= NFS_MOUNT_NORESVPORT;
+		break;
+	case Opt_fscache:
+		mnt->options |= NFS_OPTION_FSCACHE;
+		kfree(mnt->fscache_uniq);
+		mnt->fscache_uniq = NULL;
+		break;
+	case Opt_nofscache:
+		mnt->options &= ~NFS_OPTION_FSCACHE;
+		kfree(mnt->fscache_uniq);
+		mnt->fscache_uniq = NULL;
+		break;
+	case Opt_migration:
+		mnt->options |= NFS_OPTION_MIGRATION;
+		break;
+	case Opt_nomigration:
+		mnt->options &= NFS_OPTION_MIGRATION;
+		break;
+
+		/*
+		 * options that take numeric values
+		 */
+	case Opt_port:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->nfs_server.port,
+					    0, USHRT_MAX))
+			goto out_invalid_value;
+		break;
+	case Opt_rsize:
+		if (nfs_get_option_ui(mnt, args, &mnt->rsize))
+			goto out_invalid_value;
+		break;
+	case Opt_wsize:
+		if (nfs_get_option_ui(mnt, args, &mnt->wsize))
+			goto out_invalid_value;
+		break;
+	case Opt_bsize:
+		if (nfs_get_option_ui(mnt, args, &mnt->bsize))
+			goto out_invalid_value;
+		break;
+	case Opt_timeo:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->timeo, 1, INT_MAX))
+			goto out_invalid_value;
+		break;
+	case Opt_retrans:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->retrans, 0, INT_MAX))
+			goto out_invalid_value;
+		break;
+	case Opt_acregmin:
+		if (nfs_get_option_ui(mnt, args, &mnt->acregmin))
+			goto out_invalid_value;
+		break;
+	case Opt_acregmax:
+		if (nfs_get_option_ui(mnt, args, &mnt->acregmax))
+			goto out_invalid_value;
+		break;
+	case Opt_acdirmin:
+		if (nfs_get_option_ui(mnt, args, &mnt->acdirmin))
+			goto out_invalid_value;
+		break;
+	case Opt_acdirmax:
+		if (nfs_get_option_ui(mnt, args, &mnt->acdirmax))
+			goto out_invalid_value;
+		break;
+	case Opt_actimeo:
+		if (nfs_get_option_ui(mnt, args, &mnt->acdirmax))
+			goto out_invalid_value;
+		mnt->acregmin = mnt->acregmax =
+			mnt->acdirmin = mnt->acdirmax;
+		break;
+	case Opt_namelen:
+		if (nfs_get_option_ui(mnt, args, &mnt->namlen))
+			goto out_invalid_value;
+		break;
+	case Opt_mountport:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->mount_server.port,
+					    0, USHRT_MAX))
+			goto out_invalid_value;
+		break;
+	case Opt_mountvers:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->mount_server.version,
+					    NFS_MNT_VERSION, NFS_MNT3_VERSION))
+			goto out_invalid_value;
+		break;
+	case Opt_minorversion:
+		if (nfs_get_option_ui_bound(mnt, args, &mnt->minorversion,
+					    0, NFS4_MAX_MINOR_VERSION))
+			goto out_invalid_value;
+		break;
+
+		/*
+		 * options that take text values
+		 */
+	case Opt_nfsvers:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		rc = nfs_parse_version_string(string, mnt, args);
+		kfree(string);
+		if (!rc)
+			goto out_invalid_value;
+		break;
+	case Opt_sec:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		rc = nfs_parse_security_flavors(string, mnt);
+		kfree(string);
+		if (!rc) {
+			dfprintk(MOUNT, "NFS:   unrecognized security flavor\n");
+			return -EINVAL;
+		}
+		break;
+	case Opt_proto:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		token = match_token(string, nfs_xprt_protocol_tokens, args);
+
+		mnt->protofamily = AF_INET;
+		switch (token) {
+		case Opt_xprt_udp6:
+			mnt->protofamily = AF_INET6;
+		case Opt_xprt_udp:
+			mnt->flags &= ~NFS_MOUNT_TCP;
+			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
+			break;
+		case Opt_xprt_tcp6:
+			mnt->protofamily = AF_INET6;
+		case Opt_xprt_tcp:
+			mnt->flags |= NFS_MOUNT_TCP;
+			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+			break;
+		case Opt_xprt_rdma6:
+			mnt->protofamily = AF_INET6;
+		case Opt_xprt_rdma:
+			/* vector side protocols to TCP */
+			mnt->flags |= NFS_MOUNT_TCP;
+			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
+			xprt_load_transport(string);
+			break;
+		default:
+			dfprintk(MOUNT, "NFS:   unrecognized transport protocol\n");
+			kfree(string);
+			return -EINVAL;
+		}
+		kfree(string);
+		break;
+	case Opt_mountproto:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		token = match_token(string, nfs_xprt_protocol_tokens, args);
+		kfree(string);
+
+		mnt->mountfamily = AF_INET;
+		switch (token) {
+		case Opt_xprt_udp6:
+			mnt->mountfamily = AF_INET6;
+		case Opt_xprt_udp:
+			mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
+			break;
+		case Opt_xprt_tcp6:
+			mnt->mountfamily = AF_INET6;
+		case Opt_xprt_tcp:
+			mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
+			break;
+		case Opt_xprt_rdma: /* not used for side protocols */
+		default:
+			mc->error = "NFS: Unrecognized transport protocol";
+			return -EINVAL;
+		}
+		break;
+	case Opt_addr:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		mnt->nfs_server.addrlen =
+			rpc_pton(mc->net_ns, string, strlen(string),
+				 (struct sockaddr *)&mnt->nfs_server.address,
+				 sizeof(mnt->nfs_server._address));
+		kfree(string);
+		if (mnt->nfs_server.addrlen == 0)
+			goto out_invalid_address;
+		break;
+	case Opt_clientaddr:
+		if (nfs_get_option_str(args, &mnt->client_address))
+			goto out_nomem;
+		break;
+	case Opt_mounthost:
+		if (nfs_get_option_str(args, &mnt->mount_server.hostname))
+			goto out_nomem;
+		break;
+	case Opt_mountaddr:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		mnt->mount_server.addrlen =
+			rpc_pton(mc->net_ns, string, strlen(string),
+				 (struct sockaddr *)&mnt->mount_server.address,
+				 sizeof(mnt->mount_server._address));
+		kfree(string);
+		if (mnt->mount_server.addrlen == 0)
+			goto out_invalid_address;
+		break;
+	case Opt_lookupcache:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		token = match_token(string, nfs_lookupcache_tokens, args);
+		kfree(string);
+		switch (token) {
+		case Opt_lookupcache_all:
+			mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
+			break;
+		case Opt_lookupcache_positive:
+			mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
+			mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
+			break;
+		case Opt_lookupcache_none:
+			mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
+			break;
+		default:
+			mc->error = "NFS: Invalid lookupcache argument";
+			return -EINVAL;
+		}
+		break;
+	case Opt_fscache_uniq:
+		if (nfs_get_option_str(args, &mnt->fscache_uniq))
+			goto out_nomem;
+		mnt->options |= NFS_OPTION_FSCACHE;
+		break;
+	case Opt_local_lock:
+		string = match_strdup(args);
+		if (string == NULL)
+			goto out_nomem;
+		token = match_token(string, nfs_local_lock_tokens, args);
+		kfree(string);
+		switch (token) {
+		case Opt_local_lock_all:
+			mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
+				       NFS_MOUNT_LOCAL_FCNTL);
+			break;
+		case Opt_local_lock_flock:
+			mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
+			break;
+		case Opt_local_lock_posix:
+			mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
+			break;
+		case Opt_local_lock_none:
+			mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
+					NFS_MOUNT_LOCAL_FCNTL);
+			break;
+		default:
+			mc->error = "NFS: invalid local_lock argument";
+			return -EINVAL;
+		}
+		break;
+
+		/*
+		 * Special options
+		 */
+	case Opt_sloppy:
+		mc->sloppy = 1;
+		dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
+		break;
+	case Opt_userspace:
+	case Opt_deprecated:
+		dfprintk(MOUNT, "NFS:   ignoring mount option '%s'\n", p);
+		break;
+
+	default:
+		dfprintk(MOUNT, "NFS:   unrecognized mount option '%s'\n", p);
+		if (!mc->sloppy) {
+			mc->error = "NFS: Unrecognized mount option";
+			return -EINVAL;
+		}
+		break;
+	}
+
+	return 0;
+
+out_nomem:
+	printk(KERN_INFO "NFS: not enough memory to parse option\n");
+	return -ENOMEM;
+out_invalid_value:
+	mc->error = "NFS: Bad mount option value specified";
+	return -EINVAL;
+out_invalid_address:
+	mc->error = "NFS: Bad IP address specified";
+	return -EINVAL;
+}
+
+/*
+ * Validate the preparsed information in the mount context.
+ */
+static int nfs_mount_ctx_validate(struct mount_context *mc)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+	struct nfs_subversion *nfs_mod;
+	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
+	int max_namelen = PAGE_SIZE;
+	int max_pathlen = NFS_MAXPATHLEN;
+	int port = 0;
+	int ret;
+
+	if (ctx->mc.mount_type & MOUNT_TYPE_REMOUNT)
+		return 0;
+
+	if (!ctx->mc.device)
+		goto out_no_device_name;
+
+	/* Check for sanity first. */
+	if (ctx->minorversion && ctx->version != 4)
+		goto out_minorversion_mismatch;
+
+	if (ctx->options & NFS_OPTION_MIGRATION &&
+	    (ctx->version != 4 || ctx->minorversion != 0))
+		goto out_migration_misuse;
+
+	/* Verify that any proto=/mountproto= options match the address
+	 * families in the addr=/mountaddr= options.
+	 */
+	if (ctx->protofamily != AF_UNSPEC &&
+	    ctx->protofamily != ctx->nfs_server.address.sa_family)
+		goto out_proto_mismatch;
+
+	if (ctx->mountfamily != AF_UNSPEC) {
+		if (ctx->mount_server.addrlen) {
+			if (ctx->mountfamily != ctx->mount_server.address.sa_family)
+				goto out_mountproto_mismatch;
+		} else {
+			if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
+				goto out_mountproto_mismatch;
+		}
+	}
+
+	if (!nfs_verify_server_address(sap))
+		goto out_no_address;
+
+	if (ctx->version == 4) {
+		if (IS_ENABLED(CONFIG_NFS_V4)) {
+			port = NFS_PORT;
+			max_namelen = NFS4_MAXNAMLEN;
+			max_pathlen = NFS4_MAXPATHLEN;
+			nfs_validate_transport_protocol(ctx);
+			if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
+				goto out_invalid_transport_udp;
+			ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
+					 NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
+					 NFS_MOUNT_LOCAL_FCNTL);
+		} else {
+			goto out_v4_not_compiled;
+		}
+	} else {
+		nfs_set_mount_transport_protocol(ctx);
+	}
+
+	nfs_set_port(sap, &ctx->nfs_server.port, port);
+
+	ret = nfs_parse_devname(ctx, max_namelen, max_pathlen);
+	if (ret < 0)
+		return ret;
+
+	/* Load the NFS protocol module if we haven't done so yet */
+	if (!ctx->nfs_mod) {
+		nfs_mod = get_nfs_version(ctx->version);
+		if (IS_ERR(nfs_mod)) {
+			ret = PTR_ERR(nfs_mod);
+			goto out_version_unavailable;
+		}
+		ctx->nfs_mod = nfs_mod;
+	}
+	return 0;
+
+out_no_device_name:
+	mc->error = "NFS: Device name not specified";
+	return -EINVAL;
+out_v4_not_compiled:
+	mc->error = "NFS: NFSv4 is not compiled into kernel";
+	return -EPROTONOSUPPORT;
+out_invalid_transport_udp:
+	mc->error = "NFSv4: Unsupported transport protocol udp";
+	return -EINVAL;
+out_no_address:
+	mc->error = "NFS: mount program didn't pass remote address";
+	return -EINVAL;
+out_mountproto_mismatch:
+	mc->error = "NFS: Mount server address does not match mountproto= option";
+	return -EINVAL;
+out_proto_mismatch:
+	mc->error = "NFS: Server address does not match proto= option";
+	return -EINVAL;
+out_minorversion_mismatch:
+	mc->error = "NFS: Mount option does not support minorversion";
+	return -EINVAL;
+out_migration_misuse:
+	mc->error = "NFS: 'Migration' not supported for this NFS version";
+	return -EINVAL;
+out_version_unavailable:
+	mc->error = "NFS: Version unavailable";
+	return ret;
+}
+
+/*
+ * Use the preparsed information in the mount context to effect a mount.
+ */
+static struct dentry *nfs_ordinary_mount(struct nfs_mount_context *ctx)
+{
+	ctx->set_security = nfs_set_sb_security;
+
+	return ctx->nfs_mod->rpc_ops->try_mount(ctx);
+}
+
+/*
+ * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
+ */
+static struct dentry *nfs_xdev_mount(struct nfs_mount_context *ctx)
+{
+	struct nfs_server *server;
+	struct dentry *mntroot = ERR_PTR(-ENOMEM);
+
+	dprintk("--> nfs_xdev_mount()\n");
+
+	ctx->set_security = nfs_clone_sb_security;
+
+	/* create a new volume representation */
+	server = ctx->nfs_mod->rpc_ops->clone_server(NFS_SB(ctx->clone_data.sb),
+						     ctx->mntfh,
+						     ctx->clone_data.fattr,
+						     ctx->selected_flavor);
+
+	if (IS_ERR(server))
+		mntroot = ERR_CAST(server);
+	else
+		mntroot = nfs_fs_mount_common(server, ctx);
+
+	dprintk("<-- nfs_xdev_mount() = %ld\n",
+			IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
+	return mntroot;
+}
+
+/*
+ * Handle ordinary mounts inspired by the user and cross-FSID mounts.
+ */
+struct dentry *nfs_general_mount(struct nfs_mount_context *ctx)
+{
+	switch (ctx->mount_type) {
+	case NFS_MOUNT_ORDINARY:
+		return nfs_ordinary_mount(ctx);
+
+	case NFS_MOUNT_CROSS_DEV:
+		return nfs_xdev_mount(ctx);
+
+	default:
+		ctx->mc.error = "NFS: Unknown mount type";
+		return ERR_PTR(-ENOTSUPP);
+	}
+}
+EXPORT_SYMBOL_GPL(nfs_general_mount);
+
+static struct dentry *nfs_fs_mount(struct mount_context *mc)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+
+	if (!ctx->nfs_mod) {
+		pr_warn("Missing nfs_mod\n");
+		return ERR_PTR(-EINVAL);
+	}
+	if (!ctx->nfs_mod->rpc_ops) {
+		pr_warn("Missing rpc_ops\n");
+		return ERR_PTR(-EINVAL);
+	}
+	if (!ctx->nfs_mod->rpc_ops->mount) {
+		pr_warn("Missing mount\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	return ctx->nfs_mod->rpc_ops->mount(ctx);
+}
+
+/*
+ * Handle duplication of a mount context.  The caller copied *src into *mc, but
+ * it can't deal with resource pointers in the filesystem context, so we have
+ * to do that.  We need to clear pointers, copy data or get extra refs as
+ * appropriate.
+ */
+static int nfs_mount_ctx_dup(struct mount_context *mc, struct mount_context *src)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+
+	__module_get(ctx->nfs_mod->owner);
+	ctx->client_address		= NULL;
+	ctx->mount_server.hostname	= NULL;
+	ctx->nfs_server.export_path	= NULL;
+	ctx->nfs_server.hostname	= NULL;
+	ctx->fscache_uniq		= NULL;
+
+	ctx->mntfh = nfs_alloc_fhandle();
+	if (!ctx->mntfh)
+		return -ENOMEM;
+	return 0;
+}
+
+static void nfs_mount_ctx_free(struct mount_context *mc)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+
+	if (ctx->nfs_mod)
+		put_nfs_version(ctx->nfs_mod);
+	kfree(ctx->client_address);
+	kfree(ctx->mount_server.hostname);
+	if (ctx->nfs_server.export_path != nfs_slash)
+		kfree(ctx->nfs_server.export_path);
+	kfree(ctx->nfs_server.hostname);
+	kfree(ctx->fscache_uniq);
+	nfs_free_fhandle(ctx->mntfh);
+}
+
+static const struct mount_context_operations nfs_mount_ctx_ops = {
+	.free			= nfs_mount_ctx_free,
+	.dup			= nfs_mount_ctx_dup,
+	.option			= nfs_mount_ctx_option,
+	.monolithic_mount_data	= nfs_monolithic_mount_data,
+	.validate		= nfs_mount_ctx_validate,
+	.mount			= nfs_fs_mount,
+	.fill_super		= nfs_fill_super,
+};
+
+/*
+ * Initialise a mount context from an extant superblock for remounting.
+ */
+static int nfs_mount_init_from_sb(struct mount_context *mc,
+				  struct super_block *sb)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+	struct nfs_server *nfss = sb->s_fs_info;
+	struct net *net = nfss->nfs_client->cl_net;
+
+	ctx->flags		= nfss->flags;
+	ctx->rsize		= nfss->rsize;
+	ctx->wsize		= nfss->wsize;
+	ctx->retrans		= nfss->client->cl_timeout->to_retries;
+	ctx->selected_flavor	= nfss->client->cl_auth->au_flavor;
+	ctx->acregmin		= nfss->acregmin / HZ;
+	ctx->acregmax		= nfss->acregmax / HZ;
+	ctx->acdirmin		= nfss->acdirmin / HZ;
+	ctx->acdirmax		= nfss->acdirmax / HZ;
+	ctx->timeo		= 10U * nfss->client->cl_timeout->to_initval / HZ;
+	ctx->nfs_server.port	= nfss->port;
+	ctx->nfs_server.addrlen	= nfss->nfs_client->cl_addrlen;
+	ctx->version		= nfss->nfs_client->rpc_ops->version;
+	ctx->minorversion	= nfss->nfs_client->cl_minorversion;
+
+	memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
+		ctx->nfs_server.addrlen);
+
+	if (ctx->mc.net_ns != net) {
+		put_net(ctx->mc.net_ns);
+		ctx->mc.net_ns = get_net(net);
+	}
+
+	ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
+	if (!try_module_get(ctx->nfs_mod->owner)) {
+		ctx->nfs_mod = NULL;
+		mc->error = "NFS: Protocol module not available";
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+/*
+ * Prepare mount context.  We use the namespaces attached to the context.  This
+ * may be the current process's namespaces, or it may be a container's
+ * namespaces.
+ */
+static int nfs_fs_fsopen(struct mount_context *mc, struct super_block *src_sb)
+{
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+
+	ctx->mntfh = nfs_alloc_fhandle();
+	if (!ctx->mntfh)
+		return -ENOMEM;
+
+	ctx->mc.ops		= &nfs_mount_ctx_ops;
+	ctx->mount_type		= NFS_MOUNT_ORDINARY;
+	ctx->protofamily	= AF_UNSPEC;
+	ctx->mountfamily	= AF_UNSPEC;
+	ctx->mount_server.port	= NFS_UNSPEC_PORT;
+
+	if (!src_sb) {
+		ctx->timeo		= NFS_UNSPEC_TIMEO;
+		ctx->retrans		= NFS_UNSPEC_RETRANS;
+		ctx->acregmin		= NFS_DEF_ACREGMIN;
+		ctx->acregmax		= NFS_DEF_ACREGMAX;
+		ctx->acdirmin		= NFS_DEF_ACDIRMIN;
+		ctx->acdirmax		= NFS_DEF_ACDIRMAX;
+		ctx->nfs_server.port	= NFS_UNSPEC_PORT;
+		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+		ctx->selected_flavor	= RPC_AUTH_MAXFLAVOR;
+		ctx->minorversion	= 0;
+		ctx->need_mount		= true;
+		return 0;
+	}
+
+	return nfs_mount_init_from_sb(mc, src_sb);
+}
+
+struct file_system_type nfs_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "nfs",
+	.fsopen		= nfs_fs_fsopen,
+	.mc_size	= sizeof(struct nfs_mount_context),
+	.kill_sb	= nfs_kill_super,
+	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
+};
+MODULE_ALIAS_FS("nfs");
+EXPORT_SYMBOL_GPL(nfs_fs_type);
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+struct file_system_type nfs4_fs_type = {
+	.owner		= THIS_MODULE,
+	.name		= "nfs4",
+	.fsopen		= nfs_fs_fsopen,
+	.mc_size	= sizeof(struct nfs_mount_context),
+	.kill_sb	= nfs_kill_super,
+	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
+};
+MODULE_ALIAS_FS("nfs4");
+MODULE_ALIAS("nfs4");
+EXPORT_SYMBOL_GPL(nfs4_fs_type);
+#endif /* CONFIG_NFS_V4 */
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 786f17580582..9be008f7072e 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -18,6 +18,7 @@
 #include <linux/vfs.h>
 #include <linux/sunrpc/gss_api.h>
 #include "internal.h"
+#include "nfs.h"
 
 #define NFSDBG_FACILITY		NFSDBG_VFS
 
@@ -224,10 +225,9 @@ void nfs_release_automount_timer(void)
  * Clone a mountpoint of the appropriate type
  */
 static struct vfsmount *nfs_do_clone_mount(struct nfs_server *server,
-					   const char *devname,
-					   struct nfs_clone_mount *mountdata)
+					   struct nfs_mount_context *ctx)
 {
-	return vfs_submount(mountdata->dentry, &nfs_xdev_fs_type, devname, mountdata);
+	return vfs_submount_mc(ctx->clone_data.dentry, &ctx->mc);
 }
 
 /**
@@ -241,33 +241,56 @@ static struct vfsmount *nfs_do_clone_mount(struct nfs_server *server,
 struct vfsmount *nfs_do_submount(struct dentry *dentry, struct nfs_fh *fh,
 				 struct nfs_fattr *fattr, rpc_authflavor_t authflavor)
 {
-	struct nfs_clone_mount mountdata = {
-		.sb = dentry->d_sb,
-		.dentry = dentry,
-		.fh = fh,
-		.fattr = fattr,
-		.authflavor = authflavor,
-	};
-	struct vfsmount *mnt = ERR_PTR(-ENOMEM);
-	char *page = (char *) __get_free_page(GFP_USER);
-	char *devname;
+	struct nfs_mount_context *ctx;
+	struct mount_context *mc;
+	struct vfsmount *mnt;
+	char *buffer, *p;
+
+	/* Open a new mount context, transferring parameters from the parent
+	 * superblock, including the network namespace.
+	 */
+	mc = __vfs_fsopen(&nfs_fs_type, dentry->d_sb, 0, 0, MOUNT_TYPE_SUBMOUNT);
+	if (IS_ERR(mc))
+		return ERR_CAST(mc);
+	ctx = container_of(mc, struct nfs_mount_context, mc);
+
+	mnt = ERR_PTR(-ENOMEM);
+	buffer = kmalloc(4096, GFP_USER);
+	if (!buffer)
+		goto err_mc;
+
+	ctx->mount_type		= NFS_MOUNT_CROSS_DEV;
+	ctx->selected_flavor	= authflavor;
+	ctx->clone_data.sb	= dentry->d_sb;
+	ctx->clone_data.dentry	= dentry;
+	ctx->clone_data.fattr	= fattr;
+	ctx->clone_data.cloned	= true;
+
+	nfs_copy_fh(ctx->mntfh, fh);
 
 	dprintk("--> nfs_do_submount()\n");
+	dprintk("%s: submounting on %pd2\n", __func__, dentry);
 
-	dprintk("%s: submounting on %pd2\n", __func__,
-			dentry);
-	if (page == NULL)
-		goto out;
-	devname = nfs_devname(dentry, page, PAGE_SIZE);
-	mnt = (struct vfsmount *)devname;
-	if (IS_ERR(devname))
-		goto free_page;
-	mnt = nfs_do_clone_mount(NFS_SB(dentry->d_sb), devname, &mountdata);
-free_page:
-	free_page((unsigned long)page);
-out:
-	dprintk("%s: done\n", __func__);
+	p = nfs_devname(dentry, buffer, 4096);
+	if (IS_ERR(p)) {
+		mc->error = "NFS: Couldn't determine submount pathname";
+		mnt = ERR_CAST(p);
+		goto err_buffer;
+	}
 
+	ctx->mc.device = kmemdup(p, buffer + 4096 - p, GFP_KERNEL);
+	if (!ctx->mc.device)
+		goto err_buffer;
+	kfree(buffer);
+
+	mnt = nfs_do_clone_mount(NFS_SB(dentry->d_sb), ctx);
+	goto err_mc;
+
+err_buffer:
+	kfree(buffer);
+err_mc:
+	put_mount_context(mc);
+	dprintk("%s: done\n", __func__);
 	dprintk("<-- nfs_do_submount() = %p\n", mnt);
 	return mnt;
 }
diff --git a/fs/nfs/nfs3_fs.h b/fs/nfs/nfs3_fs.h
index e134d6548ab7..5f9902dfb54e 100644
--- a/fs/nfs/nfs3_fs.h
+++ b/fs/nfs/nfs3_fs.h
@@ -26,7 +26,7 @@ static inline int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
 #endif /* CONFIG_NFS_V3_ACL */
 
 /* nfs3client.c */
-struct nfs_server *nfs3_create_server(struct nfs_mount_info *, struct nfs_subversion *);
+struct nfs_server *nfs3_create_server(struct nfs_mount_context *);
 struct nfs_server *nfs3_clone_server(struct nfs_server *, struct nfs_fh *,
 				     struct nfs_fattr *, rpc_authflavor_t);
 
diff --git a/fs/nfs/nfs3client.c b/fs/nfs/nfs3client.c
index 7879f2a0fcfd..ce54664e12b5 100644
--- a/fs/nfs/nfs3client.c
+++ b/fs/nfs/nfs3client.c
@@ -45,10 +45,10 @@ static inline void nfs_init_server_aclclient(struct nfs_server *server)
 }
 #endif
 
-struct nfs_server *nfs3_create_server(struct nfs_mount_info *mount_info,
-				      struct nfs_subversion *nfs_mod)
+struct nfs_server *nfs3_create_server(struct nfs_mount_context *ctx)
 {
-	struct nfs_server *server = nfs_create_server(mount_info, nfs_mod);
+	struct nfs_server *server = nfs_create_server(ctx);
+
 	/* Create a client RPC handle for the NFS v3 ACL management interface */
 	if (!IS_ERR(server))
 		nfs_init_server_aclclient(server);
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index dc925b531f32..1e0349fc33ec 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -922,6 +922,7 @@ const struct nfs_rpc_ops nfs_v3_clientops = {
 	.file_inode_ops	= &nfs3_file_inode_operations,
 	.file_ops	= &nfs_file_operations,
 	.getroot	= nfs3_proc_get_root,
+	.mount		= nfs_general_mount,
 	.submount	= nfs_submount,
 	.try_mount	= nfs_try_mount,
 	.getattr	= nfs3_proc_getattr,
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index af285cc27ccf..e85429690089 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -467,7 +467,6 @@ extern const nfs4_stateid zero_stateid;
 /* nfs4super.c */
 struct nfs_mount_info;
 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;
@@ -477,6 +476,9 @@ extern bool recover_lost_locks;
 #define NFS4_CLIENT_ID_UNIQ_LEN		(64)
 extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];
 
+extern struct dentry *nfs4_try_mount(struct nfs_mount_context *);
+extern struct dentry *nfs4_mount(struct nfs_mount_context *);
+
 /* nfs4sysctl.c */
 #ifdef CONFIG_SYSCTL
 int nfs4_register_sysctl(void);
diff --git a/fs/nfs/nfs4client.c b/fs/nfs/nfs4client.c
index 8346ccbf2d52..041d79b4c962 100644
--- a/fs/nfs/nfs4client.c
+++ b/fs/nfs/nfs4client.c
@@ -1093,56 +1093,56 @@ static int nfs4_server_common_setup(struct nfs_server *server,
  * Create a version 4 volume record
  */
 static int nfs4_init_server(struct nfs_server *server,
-		struct nfs_parsed_mount_data *data)
+			    struct nfs_mount_context *ctx)
 {
 	struct rpc_timeout timeparms;
 	int error;
 
 	dprintk("--> nfs4_init_server()\n");
 
-	nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
-			data->timeo, data->retrans);
+	nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
+			ctx->timeo, ctx->retrans);
 
 	/* Initialise the client representation from the mount data */
-	server->flags = data->flags;
-	server->options = data->options;
-	server->auth_info = data->auth_info;
+	server->flags = ctx->flags;
+	server->options = ctx->options;
+	server->auth_info = ctx->auth_info;
 
 	/* Use the first specified auth flavor. If this flavor isn't
 	 * allowed by the server, use the SECINFO path to try the
 	 * other specified flavors */
-	if (data->auth_info.flavor_len >= 1)
-		data->selected_flavor = data->auth_info.flavors[0];
+	if (ctx->auth_info.flavor_len >= 1)
+		ctx->selected_flavor = ctx->auth_info.flavors[0];
 	else
-		data->selected_flavor = RPC_AUTH_UNIX;
+		ctx->selected_flavor = RPC_AUTH_UNIX;
 
 	/* Get a client record */
 	error = nfs4_set_client(server,
-			data->nfs_server.hostname,
-			(const struct sockaddr *)&data->nfs_server.address,
-			data->nfs_server.addrlen,
-			data->client_address,
-			data->nfs_server.protocol,
+			ctx->nfs_server.hostname,
+			(const struct sockaddr *)&ctx->nfs_server.address,
+			ctx->nfs_server.addrlen,
+			ctx->client_address,
+			ctx->nfs_server.protocol,
 			&timeparms,
-			data->minorversion,
-			data->net);
+			ctx->minorversion,
+			ctx->mc.net_ns);
 	if (error < 0)
 		goto error;
 
-	if (data->rsize)
-		server->rsize = nfs_block_size(data->rsize, NULL);
-	if (data->wsize)
-		server->wsize = nfs_block_size(data->wsize, NULL);
+	if (ctx->rsize)
+		server->rsize = nfs_block_size(ctx->rsize, NULL);
+	if (ctx->wsize)
+		server->wsize = nfs_block_size(ctx->wsize, NULL);
 
-	server->acregmin = data->acregmin * HZ;
-	server->acregmax = data->acregmax * HZ;
-	server->acdirmin = data->acdirmin * HZ;
-	server->acdirmax = data->acdirmax * HZ;
+	server->acregmin = ctx->acregmin * HZ;
+	server->acregmax = ctx->acregmax * HZ;
+	server->acdirmin = ctx->acdirmin * HZ;
+	server->acdirmax = ctx->acdirmax * HZ;
 
-	server->port = data->nfs_server.port;
+	server->port = ctx->nfs_server.port;
 
 	error = nfs_init_server_rpcclient(server, &timeparms,
-					  data->selected_flavor);
+					  ctx->selected_flavor);
 
 error:
 	/* Done */
@@ -1154,10 +1154,7 @@ static int nfs4_init_server(struct nfs_server *server,
  * Create a version 4 volume record
  * - keyed on server and FSID
  */
-/*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
-				      struct nfs_fh *mntfh)*/
-struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
-				      struct nfs_subversion *nfs_mod)
+struct nfs_server *nfs4_create_server(struct nfs_mount_context *ctx)
 {
 	struct nfs_server *server;
 	bool auth_probe;
@@ -1169,14 +1166,14 @@ struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
 	if (!server)
 		return ERR_PTR(-ENOMEM);
 
-	auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
+	auth_probe = ctx->auth_info.flavor_len < 1;
 
 	/* set up the general RPC client */
-	error = nfs4_init_server(server, mount_info->parsed);
+	error = nfs4_init_server(server, ctx);
 	if (error < 0)
 		goto error;
 
-	error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
+	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
 	if (error < 0)
 		goto error;
 
@@ -1192,8 +1189,7 @@ struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
 /*
  * Create an NFS4 referral server record
  */
-struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
-					       struct nfs_fh *mntfh)
+struct nfs_server *nfs4_create_referral_server(struct nfs_mount_context *ctx)
 {
 	struct nfs_client *parent_client;
 	struct nfs_server *server, *parent_server;
@@ -1206,7 +1202,7 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
 	if (!server)
 		return ERR_PTR(-ENOMEM);
 
-	parent_server = NFS_SB(data->sb);
+	parent_server = NFS_SB(ctx->clone_data.sb);
 	parent_client = parent_server->nfs_client;
 
 	/* Initialise the client representation from the parent server */
@@ -1214,9 +1210,10 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
 
 	/* Get a client representation.
 	 * Note: NFSv4 always uses TCP, */
-	error = nfs4_set_client(server, data->hostname,
-				data->addr,
-				data->addrlen,
+	error = nfs4_set_client(server,
+				ctx->nfs_server.hostname,
+				(const struct sockaddr *)&ctx->nfs_server.address,
+				ctx->nfs_server.addrlen,
 				parent_client->cl_ipaddr,
 				rpc_protocol(parent_server->client),
 				parent_server->client->cl_timeout,
@@ -1225,13 +1222,14 @@ struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
 	if (error < 0)
 		goto error;
 
-	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
+	error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
+					  ctx->selected_flavor);
 	if (error < 0)
 		goto error;
 
 	auth_probe = parent_server->auth_info.flavor_len < 1;
 
-	error = nfs4_server_common_setup(server, mntfh, auth_probe);
+	error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
 	if (error < 0)
 		goto error;
 
diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c
index d8b040bd9814..2f1af5bdf93a 100644
--- a/fs/nfs/nfs4namespace.c
+++ b/fs/nfs/nfs4namespace.c
@@ -7,6 +7,7 @@
  * NFSv4 namespace
  */
 
+#include <linux/module.h>
 #include <linux/dcache.h>
 #include <linux/mount.h>
 #include <linux/namei.h>
@@ -20,37 +21,64 @@
 #include <linux/inet.h>
 #include "internal.h"
 #include "nfs4_fs.h"
+#include "nfs.h"
 #include "dns_resolve.h"
 
 #define NFSDBG_FACILITY		NFSDBG_VFS
 
 /*
+ * Work out the length that an NFSv4 path would render to as a standard posix
+ * path, with a leading slash but no terminating slash.
+ */
+static ssize_t nfs4_pathname_len(const struct nfs4_pathname *pathname)
+{
+	ssize_t len;
+	int i;
+
+	for (i = 0; i < pathname->ncomponents; i++) {
+		const struct nfs4_string *component = &pathname->components[i];
+
+		if (component->len > NAME_MAX)
+			goto too_long;
+		len += 1 + component->len; /* Adding "/foo" */
+		if (len > PATH_MAX)
+			goto too_long;
+	}
+	return len;
+
+too_long:
+	return -ENAMETOOLONG;
+}
+
+/*
  * Convert the NFSv4 pathname components into a standard posix path.
- *
- * Note that the resulting string will be placed at the end of the buffer
  */
-static inline char *nfs4_pathname_string(const struct nfs4_pathname *pathname,
-					 char *buffer, ssize_t buflen)
+static char *nfs4_pathname_string(const struct nfs4_pathname *pathname,
+				  unsigned short *_len)
 {
-	char *end = buffer + buflen;
-	int n;
+	ssize_t len;
+	char *buf, *p;
+	int i;
 
-	*--end = '\0';
-	buflen--;
-
-	n = pathname->ncomponents;
-	while (--n >= 0) {
-		const struct nfs4_string *component = &pathname->components[n];
-		buflen -= component->len + 1;
-		if (buflen < 0)
-			goto Elong;
-		end -= component->len;
-		memcpy(end, component->data, component->len);
-		*--end = '/';
+	len = nfs4_pathname_len(pathname);
+	if (len < 0)
+		return ERR_PTR(len);
+	*_len = len;
+
+	p = buf = kmalloc(len + 1, GFP_KERNEL);
+	if (!buf)
+		return ERR_PTR(-ENOMEM);
+
+	for (i = 0; i < pathname->ncomponents; i++) {
+		const struct nfs4_string *component = &pathname->components[i];
+
+		*p++ = '/';
+		memcpy(p, component->data, component->len);
+		p += component->len;
 	}
-	return end;
-Elong:
-	return ERR_PTR(-ENAMETOOLONG);
+
+	*p = 0;
+	return buf;
 }
 
 /*
@@ -99,21 +127,25 @@ static char *nfs4_path(struct dentry *dentry, char *buffer, ssize_t buflen)
  */
 static int nfs4_validate_fspath(struct dentry *dentry,
 				const struct nfs4_fs_locations *locations,
-				char *page, char *page2)
+				struct nfs_mount_context *ctx)
 {
-	const char *path, *fs_path;
+	const char *path;
+	char *buf;
+	int n;
 
-	path = nfs4_path(dentry, page, PAGE_SIZE);
-	if (IS_ERR(path))
+	buf = kmalloc(4096, GFP_KERNEL);
+	path = nfs4_path(dentry, buf, 4096);
+	if (IS_ERR(path)) {
+		kfree(buf);
 		return PTR_ERR(path);
+	}
 
-	fs_path = nfs4_pathname_string(&locations->fs_path, page2, PAGE_SIZE);
-	if (IS_ERR(fs_path))
-		return PTR_ERR(fs_path);
-
-	if (strncmp(path, fs_path, strlen(fs_path)) != 0) {
+	n = strncmp(path, ctx->nfs_server.export_path,
+		    ctx->nfs_server.export_path_len);
+	kfree(buf);
+	if (n != 0) {
 		dprintk("%s: path %s does not begin with fsroot %s\n",
-			__func__, path, fs_path);
+			__func__, path, ctx->nfs_server.export_path);
 		return -ENOENT;
 	}
 
@@ -234,56 +266,66 @@ nfs4_negotiate_security(struct rpc_clnt *clnt, struct inode *inode,
 	return new;
 }
 
-static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
-				     char *page, char *page2,
+static struct vfsmount *try_location(struct dentry *dentry,
+				     struct nfs_mount_context *ctx,
 				     const struct nfs4_fs_location *location)
 {
-	const size_t addr_bufsize = sizeof(struct sockaddr_storage);
-	struct net *net = rpc_net_ns(NFS_SB(mountdata->sb)->client);
+	struct net *net = rpc_net_ns(NFS_SB(dentry->d_sb)->client);
 	struct vfsmount *mnt = ERR_PTR(-ENOENT);
-	char *mnt_path;
-	unsigned int maxbuflen;
-	unsigned int s;
+	unsigned int len, s;
+	char *p;
 
-	mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE);
-	if (IS_ERR(mnt_path))
-		return ERR_CAST(mnt_path);
-	mountdata->mnt_path = mnt_path;
-	maxbuflen = mnt_path - 1 - page2;
+	/* Allocate a buffer big enough to hold any of the hostnames plus a
+	 * terminating char and also a buffer big enough to hold the hostname
+	 * plus a colon plus the path.
+	 */
+	len = 0;
+	for (s = 0; s < location->nservers; s++) {
+		const struct nfs4_string *buf = &location->servers[s];
+		if (buf->len > len)
+			len = buf->len;
+	}
 
-	mountdata->addr = kmalloc(addr_bufsize, GFP_KERNEL);
-	if (mountdata->addr == NULL)
+	ctx->nfs_server.hostname = kmalloc(len + 1, GFP_KERNEL);
+	if (!ctx->nfs_server.hostname)
 		return ERR_PTR(-ENOMEM);
 
+	ctx->mc.device = kmalloc(len + 1 + ctx->nfs_server.export_path_len + 1,
+				 GFP_KERNEL);
+	if (!ctx->mc.device)
+		return ERR_PTR(-ENOMEM);
+	
 	for (s = 0; s < location->nservers; s++) {
 		const struct nfs4_string *buf = &location->servers[s];
 
-		if (buf->len <= 0 || buf->len >= maxbuflen)
-			continue;
-
 		if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len))
 			continue;
 
-		mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len,
-				mountdata->addr, addr_bufsize, net);
-		if (mountdata->addrlen == 0)
+		ctx->nfs_server.addrlen =
+			nfs_parse_server_name(buf->data, buf->len,
+					      &ctx->nfs_server.address,
+					      sizeof(ctx->nfs_server._address),
+					      net);
+		if (ctx->nfs_server.addrlen == 0)
 			continue;
 
-		rpc_set_port(mountdata->addr, NFS_PORT);
+		rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
 
-		memcpy(page2, buf->data, buf->len);
-		page2[buf->len] = '\0';
-		mountdata->hostname = page2;
+		memcpy(ctx->nfs_server.hostname, buf->data, buf->len);
+		ctx->nfs_server.hostname[buf->len] = '\0';
 
-		snprintf(page, PAGE_SIZE, "%s:%s",
-				mountdata->hostname,
-				mountdata->mnt_path);
+		p = ctx->mc.device;
+		memcpy(p, buf->data, buf->len);
+		p += buf->len;
+		*p++ = ':';
+		memcpy(p, ctx->nfs_server.export_path, ctx->nfs_server.export_path_len);
+		p += ctx->nfs_server.export_path_len;
+		*p = 0;
 
-		mnt = vfs_submount(mountdata->dentry, &nfs4_referral_fs_type, page, mountdata);
+		mnt = vfs_submount_mc(ctx->clone_data.dentry, &ctx->mc);
 		if (!IS_ERR(mnt))
 			break;
 	}
-	kfree(mountdata->addr);
 	return mnt;
 }
 
@@ -296,33 +338,42 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
 static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
 					    const struct nfs4_fs_locations *locations)
 {
-	struct vfsmount *mnt = ERR_PTR(-ENOENT);
-	struct nfs_clone_mount mountdata = {
-		.sb = dentry->d_sb,
-		.dentry = dentry,
-		.authflavor = NFS_SB(dentry->d_sb)->client->cl_auth->au_flavor,
-	};
-	char *page = NULL, *page2 = NULL;
+	struct nfs_mount_context *ctx;
+	struct mount_context *mc;
+	struct vfsmount *mnt;
+	char *export_path;
 	int loc, error;
 
 	if (locations == NULL || locations->nlocations <= 0)
 		goto out;
 
+	mc = __vfs_fsopen(&nfs4_fs_type, dentry->d_sb, 0, 0, MOUNT_TYPE_SUBMOUNT);
+	if (IS_ERR(mc)) {
+		mnt = ERR_CAST(mc);
+		goto out;
+	}
+	ctx = container_of(mc, struct nfs_mount_context, mc);
+
 	dprintk("%s: referral at %pd2\n", __func__, dentry);
 
-	page = (char *) __get_free_page(GFP_USER);
-	if (!page)
-		goto out;
+	ctx->mount_type		= NFS4_MOUNT_REFERRAL;
+	ctx->clone_data.sb	= dentry->d_sb;
+	ctx->clone_data.dentry	= dentry;
+	ctx->clone_data.cloned	= true;
 
-	page2 = (char *) __get_free_page(GFP_USER);
-	if (!page2)
-		goto out;
+	export_path = nfs4_pathname_string(&locations->fs_path,
+					   &ctx->nfs_server.export_path_len);
+	if (IS_ERR(export_path)) {
+		mnt = ERR_CAST(export_path);
+		goto out_mc;
+	}
+	ctx->nfs_server.export_path = export_path;
 
 	/* Ensure fs path is a prefix of current dentry path */
-	error = nfs4_validate_fspath(dentry, locations, page, page2);
+	error = nfs4_validate_fspath(dentry, locations, ctx);
 	if (error < 0) {
 		mnt = ERR_PTR(error);
-		goto out;
+		goto out_mc;
 	}
 
 	for (loc = 0; loc < locations->nlocations; loc++) {
@@ -332,14 +383,14 @@ static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
 		    location->rootpath.ncomponents == 0)
 			continue;
 
-		mnt = try_location(&mountdata, page, page2, location);
+		mnt = try_location(ctx->clone_data.dentry, ctx, location);
 		if (!IS_ERR(mnt))
 			break;
 	}
 
+out_mc:
+	put_mount_context(mc);
 out:
-	free_page((unsigned long) page);
-	free_page((unsigned long) page2);
 	dprintk("%s: done\n", __func__);
 	return mnt;
 }
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 201ca3f2c4ba..32d8c10bc45e 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -9318,6 +9318,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
 	.file_inode_ops	= &nfs4_file_inode_operations,
 	.file_ops	= &nfs4_file_operations,
 	.getroot	= nfs4_proc_get_root,
+	.mount		= nfs4_mount,
 	.submount	= nfs4_submount,
 	.try_mount	= nfs4_try_mount,
 	.getattr	= nfs4_proc_getattr,
diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
index 6fb7cb6b3f4b..a71cea1ff0e1 100644
--- a/fs/nfs/nfs4super.c
+++ b/fs/nfs/nfs4super.c
@@ -17,36 +17,9 @@
 
 static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc);
 static void nfs4_evict_inode(struct inode *inode);
-static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *raw_data);
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *raw_data);
-static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *raw_data);
-
-static struct file_system_type nfs4_remote_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs4",
-	.mount		= nfs4_remote_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-
-static struct file_system_type nfs4_remote_referral_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs4",
-	.mount		= nfs4_remote_referral_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-
-struct file_system_type nfs4_referral_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs4",
-	.mount		= nfs4_referral_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
+static struct dentry *nfs4_remote_mount(struct nfs_mount_context *ctx);
+static struct dentry *nfs4_referral_mount(struct nfs_mount_context *ctx);
+static struct dentry *nfs4_remote_referral_mount(struct nfs_mount_context *ctx);
 
 static const struct super_operations nfs4_sops = {
 	.alloc_inode	= nfs_alloc_inode,
@@ -60,16 +33,16 @@ static const struct super_operations nfs4_sops = {
 	.show_devname	= nfs_show_devname,
 	.show_path	= nfs_show_path,
 	.show_stats	= nfs_show_stats,
-	.remount_fs	= nfs_remount,
+	.remount_fs_mc	= nfs_remount,
 };
 
 struct nfs_subversion nfs_v4 = {
-	.owner = THIS_MODULE,
-	.nfs_fs   = &nfs4_fs_type,
-	.rpc_vers = &nfs_version4,
-	.rpc_ops  = &nfs_v4_clientops,
-	.sops     = &nfs4_sops,
-	.xattr    = nfs4_xattr_handlers,
+	.owner		= THIS_MODULE,
+	.nfs_fs		= &nfs4_fs_type,
+	.rpc_vers	= &nfs_version4,
+	.rpc_ops	= &nfs_v4_clientops,
+	.sops		= &nfs4_sops,
+	.xattr		= nfs4_xattr_handlers,
 };
 
 static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc)
@@ -103,47 +76,58 @@ static void nfs4_evict_inode(struct inode *inode)
 /*
  * Get the superblock for the NFS4 root partition
  */
-static struct dentry *
-nfs4_remote_mount(struct file_system_type *fs_type, int flags,
-		  const char *dev_name, void *info)
+static struct dentry *nfs4_remote_mount(struct nfs_mount_context *ctx)
 {
-	struct nfs_mount_info *mount_info = info;
 	struct nfs_server *server;
-	struct dentry *mntroot = ERR_PTR(-ENOMEM);
 
-	mount_info->set_security = nfs_set_sb_security;
+	ctx->set_security = nfs_set_sb_security;
 
 	/* Get a volume representation */
-	server = nfs4_create_server(mount_info, &nfs_v4);
-	if (IS_ERR(server)) {
-		mntroot = ERR_CAST(server);
-		goto out;
-	}
-
-	mntroot = nfs_fs_mount_common(server, flags, dev_name, mount_info, &nfs_v4);
+	server = nfs4_create_server(ctx);
+	if (IS_ERR(server))
+		return ERR_CAST(server);
 
-out:
-	return mntroot;
+	return nfs_fs_mount_common(server, ctx);
 }
 
-static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
-		int flags, void *data, const char *hostname)
+/*
+ * Create a mount for the root of the server.  We copy the mount context we
+ * have for the parameters and set its hostname, path and type.
+ */
+static struct vfsmount *nfs_do_root_mount(struct nfs_mount_context *ctx,
+					  const char *hostname,
+					  enum nfs_mount_type type)
 {
+	struct nfs_mount_context *root_ctx;
+	struct mount_context *root_mc;
 	struct vfsmount *root_mnt;
 	char *root_devname;
 	size_t len;
 
+	root_mc = vfs_dup_mount_context(&ctx->mc);
+	if (IS_ERR(root_mc))
+		return ERR_CAST(root_mc);
+	root_ctx = container_of(root_mc, struct nfs_mount_context, mc);
+
+	root_ctx->mount_type = type;
+	root_ctx->nfs_server.export_path = (char *)nfs_slash;
+
 	len = strlen(hostname) + 5;
+	root_mnt = ERR_PTR(-ENOMEM);
 	root_devname = kmalloc(len, GFP_KERNEL);
 	if (root_devname == NULL)
-		return ERR_PTR(-ENOMEM);
+		goto out_mc;
+
 	/* Does hostname needs to be enclosed in brackets? */
 	if (strchr(hostname, ':'))
 		snprintf(root_devname, len, "[%s]:/", hostname);
 	else
 		snprintf(root_devname, len, "%s:/", hostname);
-	root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
-	kfree(root_devname);
+	root_ctx->mc.device = root_devname;
+
+	root_mnt = vfs_kern_mount_mc(&root_ctx->mc);
+out_mc:
+	put_mount_context(root_mc);
 	return root_mnt;
 }
 
@@ -234,24 +218,24 @@ static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
 	return dentry;
 }
 
-struct dentry *nfs4_try_mount(int flags, const char *dev_name,
-			      struct nfs_mount_info *mount_info,
-			      struct nfs_subversion *nfs_mod)
+struct dentry *nfs4_try_mount(struct nfs_mount_context *ctx)
 {
-	char *export_path;
 	struct vfsmount *root_mnt;
 	struct dentry *res;
-	struct nfs_parsed_mount_data *data = mount_info->parsed;
 
 	dfprintk(MOUNT, "--> nfs4_try_mount()\n");
 
-	export_path = data->nfs_server.export_path;
-	data->nfs_server.export_path = "/";
-	root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,
-			data->nfs_server.hostname);
-	data->nfs_server.export_path = export_path;
+	/* We create a mount for the server's root, walk to the requested
+	 * location and then create another mount for that.
+	 */
+	root_mnt = nfs_do_root_mount(ctx, ctx->nfs_server.hostname,
+				     NFS4_MOUNT_REMOTE);
+	if (IS_ERR(root_mnt))
+		return ERR_CAST(root_mnt);
 
-	res = nfs_follow_remote_path(root_mnt, export_path);
+	res = nfs_follow_remote_path(root_mnt, ctx->nfs_server.export_path);
+	if (res < 0)
+		ctx->mc.error = "NFS4: Couldn't follow remote path";
 
 	dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n",
 		 PTR_ERR_OR_ZERO(res),
@@ -259,64 +243,64 @@ struct dentry *nfs4_try_mount(int flags, const char *dev_name,
 	return res;
 }
 
-static struct dentry *
-nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
-			   const char *dev_name, void *raw_data)
+static struct dentry *nfs4_remote_referral_mount(struct nfs_mount_context *ctx)
 {
-	struct nfs_mount_info mount_info = {
-		.fill_super = nfs_fill_super,
-		.set_security = nfs_clone_sb_security,
-		.cloned = raw_data,
-	};
 	struct nfs_server *server;
-	struct dentry *mntroot = ERR_PTR(-ENOMEM);
 
 	dprintk("--> nfs4_referral_get_sb()\n");
 
-	mount_info.mntfh = nfs_alloc_fhandle();
-	if (mount_info.cloned == NULL || mount_info.mntfh == NULL)
-		goto out;
+	ctx->set_security = nfs_clone_sb_security;
+
+	if (!ctx->clone_data.cloned)
+		return ERR_PTR(-EINVAL);
 
 	/* create a new volume representation */
-	server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh);
-	if (IS_ERR(server)) {
-		mntroot = ERR_CAST(server);
-		goto out;
-	}
+	server = nfs4_create_referral_server(ctx);
+	if (IS_ERR(server))
+		return ERR_CAST(server);
 
-	mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, &nfs_v4);
-out:
-	nfs_free_fhandle(mount_info.mntfh);
-	return mntroot;
+	return nfs_fs_mount_common(server, ctx);
 }
 
 /*
  * Create an NFS4 server record on referral traversal
  */
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
-		int flags, const char *dev_name, void *raw_data)
+static struct dentry *nfs4_referral_mount(struct nfs_mount_context *ctx)
 {
-	struct nfs_clone_mount *data = raw_data;
-	char *export_path;
 	struct vfsmount *root_mnt;
 	struct dentry *res;
 
 	dprintk("--> nfs4_referral_mount()\n");
 
-	export_path = data->mnt_path;
-	data->mnt_path = "/";
-
-	root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
-			flags, data, data->hostname);
-	data->mnt_path = export_path;
+	root_mnt = nfs_do_root_mount(ctx, ctx->nfs_server.hostname,
+				     NFS4_MOUNT_REMOTE_REFERRAL);
 
-	res = nfs_follow_remote_path(root_mnt, export_path);
+	res = nfs_follow_remote_path(root_mnt, ctx->nfs_server.export_path);
 	dprintk("<-- nfs4_referral_mount() = %d%s\n",
 		PTR_ERR_OR_ZERO(res),
 		IS_ERR(res) ? " [error]" : "");
 	return res;
 }
 
+/*
+ * Handle special NFS4 mount types.
+ */
+struct dentry *nfs4_mount(struct nfs_mount_context *ctx)
+{
+	switch (ctx->mount_type) {
+	case NFS4_MOUNT_REMOTE:
+		return nfs4_remote_mount(ctx);
+
+	case NFS4_MOUNT_REFERRAL:
+		return nfs4_referral_mount(ctx);
+
+	case NFS4_MOUNT_REMOTE_REFERRAL:
+		return nfs4_remote_referral_mount(ctx);
+
+	default:
+		return nfs_general_mount(ctx);
+	}
+}
 
 static int __init init_nfs_v4(void)
 {
diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index b7bca8303989..edae9cd50412 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -704,6 +704,7 @@ const struct nfs_rpc_ops nfs_v2_clientops = {
 	.file_inode_ops	= &nfs_file_inode_operations,
 	.file_ops	= &nfs_file_operations,
 	.getroot	= nfs_proc_get_root,
+	.mount		= nfs_general_mount,
 	.submount	= nfs_submount,
 	.try_mount	= nfs_try_mount,
 	.getattr	= nfs_proc_getattr,
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index dc69314d455e..82d4a3071517 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -68,244 +68,6 @@
 #include "nfs.h"
 
 #define NFSDBG_FACILITY		NFSDBG_VFS
-#define NFS_TEXT_DATA		1
-
-#if IS_ENABLED(CONFIG_NFS_V3)
-#define NFS_DEFAULT_VERSION 3
-#else
-#define NFS_DEFAULT_VERSION 2
-#endif
-
-enum {
-	/* Mount options that take no arguments */
-	Opt_soft, Opt_hard,
-	Opt_posix, Opt_noposix,
-	Opt_cto, Opt_nocto,
-	Opt_ac, Opt_noac,
-	Opt_lock, Opt_nolock,
-	Opt_udp, Opt_tcp, Opt_rdma,
-	Opt_acl, Opt_noacl,
-	Opt_rdirplus, Opt_nordirplus,
-	Opt_sharecache, Opt_nosharecache,
-	Opt_resvport, Opt_noresvport,
-	Opt_fscache, Opt_nofscache,
-	Opt_migration, Opt_nomigration,
-
-	/* Mount options that take integer arguments */
-	Opt_port,
-	Opt_rsize, Opt_wsize, Opt_bsize,
-	Opt_timeo, Opt_retrans,
-	Opt_acregmin, Opt_acregmax,
-	Opt_acdirmin, Opt_acdirmax,
-	Opt_actimeo,
-	Opt_namelen,
-	Opt_mountport,
-	Opt_mountvers,
-	Opt_minorversion,
-
-	/* Mount options that take string arguments */
-	Opt_nfsvers,
-	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
-	Opt_addr, Opt_mountaddr, Opt_clientaddr,
-	Opt_lookupcache,
-	Opt_fscache_uniq,
-	Opt_local_lock,
-
-	/* Special mount options */
-	Opt_userspace, Opt_deprecated, Opt_sloppy,
-
-	Opt_err
-};
-
-static const match_table_t nfs_mount_option_tokens = {
-	{ Opt_userspace, "bg" },
-	{ Opt_userspace, "fg" },
-	{ Opt_userspace, "retry=%s" },
-
-	{ Opt_sloppy, "sloppy" },
-
-	{ Opt_soft, "soft" },
-	{ Opt_hard, "hard" },
-	{ Opt_deprecated, "intr" },
-	{ Opt_deprecated, "nointr" },
-	{ Opt_posix, "posix" },
-	{ Opt_noposix, "noposix" },
-	{ Opt_cto, "cto" },
-	{ Opt_nocto, "nocto" },
-	{ Opt_ac, "ac" },
-	{ Opt_noac, "noac" },
-	{ Opt_lock, "lock" },
-	{ Opt_nolock, "nolock" },
-	{ Opt_udp, "udp" },
-	{ Opt_tcp, "tcp" },
-	{ Opt_rdma, "rdma" },
-	{ Opt_acl, "acl" },
-	{ Opt_noacl, "noacl" },
-	{ Opt_rdirplus, "rdirplus" },
-	{ Opt_nordirplus, "nordirplus" },
-	{ Opt_sharecache, "sharecache" },
-	{ Opt_nosharecache, "nosharecache" },
-	{ Opt_resvport, "resvport" },
-	{ Opt_noresvport, "noresvport" },
-	{ Opt_fscache, "fsc" },
-	{ Opt_nofscache, "nofsc" },
-	{ Opt_migration, "migration" },
-	{ Opt_nomigration, "nomigration" },
-
-	{ Opt_port, "port=%s" },
-	{ Opt_rsize, "rsize=%s" },
-	{ Opt_wsize, "wsize=%s" },
-	{ Opt_bsize, "bsize=%s" },
-	{ Opt_timeo, "timeo=%s" },
-	{ Opt_retrans, "retrans=%s" },
-	{ Opt_acregmin, "acregmin=%s" },
-	{ Opt_acregmax, "acregmax=%s" },
-	{ Opt_acdirmin, "acdirmin=%s" },
-	{ Opt_acdirmax, "acdirmax=%s" },
-	{ Opt_actimeo, "actimeo=%s" },
-	{ Opt_namelen, "namlen=%s" },
-	{ Opt_mountport, "mountport=%s" },
-	{ Opt_mountvers, "mountvers=%s" },
-	{ Opt_minorversion, "minorversion=%s" },
-
-	{ Opt_nfsvers, "nfsvers=%s" },
-	{ Opt_nfsvers, "vers=%s" },
-
-	{ Opt_sec, "sec=%s" },
-	{ Opt_proto, "proto=%s" },
-	{ Opt_mountproto, "mountproto=%s" },
-	{ Opt_addr, "addr=%s" },
-	{ Opt_clientaddr, "clientaddr=%s" },
-	{ Opt_mounthost, "mounthost=%s" },
-	{ Opt_mountaddr, "mountaddr=%s" },
-
-	{ Opt_lookupcache, "lookupcache=%s" },
-	{ Opt_fscache_uniq, "fsc=%s" },
-	{ Opt_local_lock, "local_lock=%s" },
-
-	/* The following needs to be listed after all other options */
-	{ Opt_nfsvers, "v%s" },
-
-	{ Opt_err, NULL }
-};
-
-enum {
-	Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
-	Opt_xprt_rdma6,
-
-	Opt_xprt_err
-};
-
-static const match_table_t nfs_xprt_protocol_tokens = {
-	{ Opt_xprt_udp, "udp" },
-	{ Opt_xprt_udp6, "udp6" },
-	{ Opt_xprt_tcp, "tcp" },
-	{ Opt_xprt_tcp6, "tcp6" },
-	{ Opt_xprt_rdma, "rdma" },
-	{ Opt_xprt_rdma6, "rdma6" },
-
-	{ Opt_xprt_err, NULL }
-};
-
-enum {
-	Opt_sec_none, Opt_sec_sys,
-	Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
-	Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
-	Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
-
-	Opt_sec_err
-};
-
-static const match_table_t nfs_secflavor_tokens = {
-	{ Opt_sec_none, "none" },
-	{ Opt_sec_none, "null" },
-	{ Opt_sec_sys, "sys" },
-
-	{ Opt_sec_krb5, "krb5" },
-	{ Opt_sec_krb5i, "krb5i" },
-	{ Opt_sec_krb5p, "krb5p" },
-
-	{ Opt_sec_lkey, "lkey" },
-	{ Opt_sec_lkeyi, "lkeyi" },
-	{ Opt_sec_lkeyp, "lkeyp" },
-
-	{ Opt_sec_spkm, "spkm3" },
-	{ Opt_sec_spkmi, "spkm3i" },
-	{ Opt_sec_spkmp, "spkm3p" },
-
-	{ Opt_sec_err, NULL }
-};
-
-enum {
-	Opt_lookupcache_all, Opt_lookupcache_positive,
-	Opt_lookupcache_none,
-
-	Opt_lookupcache_err
-};
-
-static match_table_t nfs_lookupcache_tokens = {
-	{ Opt_lookupcache_all, "all" },
-	{ Opt_lookupcache_positive, "pos" },
-	{ Opt_lookupcache_positive, "positive" },
-	{ Opt_lookupcache_none, "none" },
-
-	{ Opt_lookupcache_err, NULL }
-};
-
-enum {
-	Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
-	Opt_local_lock_none,
-
-	Opt_local_lock_err
-};
-
-static match_table_t nfs_local_lock_tokens = {
-	{ Opt_local_lock_all, "all" },
-	{ Opt_local_lock_flock, "flock" },
-	{ Opt_local_lock_posix, "posix" },
-	{ Opt_local_lock_none, "none" },
-
-	{ Opt_local_lock_err, NULL }
-};
-
-enum {
-	Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
-	Opt_vers_4_1, Opt_vers_4_2,
-
-	Opt_vers_err
-};
-
-static match_table_t nfs_vers_tokens = {
-	{ Opt_vers_2, "2" },
-	{ Opt_vers_3, "3" },
-	{ Opt_vers_4, "4" },
-	{ Opt_vers_4_0, "4.0" },
-	{ Opt_vers_4_1, "4.1" },
-	{ Opt_vers_4_2, "4.2" },
-
-	{ Opt_vers_err, NULL }
-};
-
-static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
-		int flags, const char *dev_name, void *raw_data);
-
-struct file_system_type nfs_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs",
-	.mount		= nfs_fs_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-MODULE_ALIAS_FS("nfs");
-EXPORT_SYMBOL_GPL(nfs_fs_type);
-
-struct file_system_type nfs_xdev_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs",
-	.mount		= nfs_xdev_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
 
 const struct super_operations nfs_sops = {
 	.alloc_inode	= nfs_alloc_inode,
@@ -319,26 +81,11 @@ const struct super_operations nfs_sops = {
 	.show_devname	= nfs_show_devname,
 	.show_path	= nfs_show_path,
 	.show_stats	= nfs_show_stats,
-	.remount_fs	= nfs_remount,
+	.remount_fs_mc	= nfs_remount,
 };
 EXPORT_SYMBOL_GPL(nfs_sops);
 
 #if IS_ENABLED(CONFIG_NFS_V4)
-static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
-static int nfs4_validate_mount_data(void *options,
-	struct nfs_parsed_mount_data *args, const char *dev_name);
-
-struct file_system_type nfs4_fs_type = {
-	.owner		= THIS_MODULE,
-	.name		= "nfs4",
-	.mount		= nfs_fs_mount,
-	.kill_sb	= nfs_kill_super,
-	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-MODULE_ALIAS_FS("nfs4");
-MODULE_ALIAS("nfs4");
-EXPORT_SYMBOL_GPL(nfs4_fs_type);
-
 static int __init register_nfs4_fs(void)
 {
 	return register_filesystem(&nfs4_fs_type);
@@ -910,141 +657,6 @@ void nfs_umount_begin(struct super_block *sb)
 }
 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 
-static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
-{
-	struct nfs_parsed_mount_data *data;
-
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
-	if (data) {
-		data->timeo		= NFS_UNSPEC_TIMEO;
-		data->retrans		= NFS_UNSPEC_RETRANS;
-		data->acregmin		= NFS_DEF_ACREGMIN;
-		data->acregmax		= NFS_DEF_ACREGMAX;
-		data->acdirmin		= NFS_DEF_ACDIRMIN;
-		data->acdirmax		= NFS_DEF_ACDIRMAX;
-		data->mount_server.port	= NFS_UNSPEC_PORT;
-		data->nfs_server.port	= NFS_UNSPEC_PORT;
-		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-		data->selected_flavor	= RPC_AUTH_MAXFLAVOR;
-		data->minorversion	= 0;
-		data->need_mount	= true;
-		data->net		= current->nsproxy->net_ns;
-		security_init_mnt_opts(&data->lsm_opts);
-	}
-	return data;
-}
-
-static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
-{
-	if (data) {
-		kfree(data->client_address);
-		kfree(data->mount_server.hostname);
-		kfree(data->nfs_server.export_path);
-		kfree(data->nfs_server.hostname);
-		kfree(data->fscache_uniq);
-		security_free_mnt_opts(&data->lsm_opts);
-		kfree(data);
-	}
-}
-
-/*
- * Sanity-check a server address provided by the mount command.
- *
- * Address family must be initialized, and address must not be
- * the ANY address for that family.
- */
-static int nfs_verify_server_address(struct sockaddr *addr)
-{
-	switch (addr->sa_family) {
-	case AF_INET: {
-		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
-		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
-	}
-	case AF_INET6: {
-		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
-		return !ipv6_addr_any(sa);
-	}
-	}
-
-	dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
-	return 0;
-}
-
-/*
- * Select between a default port value and a user-specified port value.
- * If a zero value is set, then autobind will be used.
- */
-static void nfs_set_port(struct sockaddr *sap, int *port,
-				 const unsigned short default_port)
-{
-	if (*port == NFS_UNSPEC_PORT)
-		*port = default_port;
-
-	rpc_set_port(sap, *port);
-}
-
-/*
- * Sanity check the NFS transport protocol.
- *
- */
-static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
-{
-	switch (mnt->nfs_server.protocol) {
-	case XPRT_TRANSPORT_UDP:
-	case XPRT_TRANSPORT_TCP:
-	case XPRT_TRANSPORT_RDMA:
-		break;
-	default:
-		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-	}
-}
-
-/*
- * For text based NFSv2/v3 mounts, the mount protocol transport default
- * settings should depend upon the specified NFS transport.
- */
-static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
-{
-	nfs_validate_transport_protocol(mnt);
-
-	if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
-	    mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
-			return;
-	switch (mnt->nfs_server.protocol) {
-	case XPRT_TRANSPORT_UDP:
-		mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
-		break;
-	case XPRT_TRANSPORT_TCP:
-	case XPRT_TRANSPORT_RDMA:
-		mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
-	}
-}
-
-/*
- * Add 'flavor' to 'auth_info' if not already present.
- * Returns true if 'flavor' ends up in the list, false otherwise
- */
-static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
-			      rpc_authflavor_t flavor)
-{
-	unsigned int i;
-	unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
-
-	/* make sure this flavor isn't already in the list */
-	for (i = 0; i < auth_info->flavor_len; i++) {
-		if (flavor == auth_info->flavors[i])
-			return true;
-	}
-
-	if (auth_info->flavor_len + 1 >= max_flavor_len) {
-		dfprintk(MOUNT, "NFS: too many sec= flavors\n");
-		return false;
-	}
-
-	auth_info->flavors[auth_info->flavor_len++] = flavor;
-	return true;
-}
-
 /*
  * Return true if 'match' is in auth_info or auth_info is empty.
  * Return false otherwise.
@@ -1066,628 +678,11 @@ bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
 
 /*
- * Parse the value of the 'sec=' option.
- */
-static int nfs_parse_security_flavors(char *value,
-				      struct nfs_parsed_mount_data *mnt)
-{
-	substring_t args[MAX_OPT_ARGS];
-	rpc_authflavor_t pseudoflavor;
-	char *p;
-
-	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
-
-	while ((p = strsep(&value, ":")) != NULL) {
-		switch (match_token(p, nfs_secflavor_tokens, args)) {
-		case Opt_sec_none:
-			pseudoflavor = RPC_AUTH_NULL;
-			break;
-		case Opt_sec_sys:
-			pseudoflavor = RPC_AUTH_UNIX;
-			break;
-		case Opt_sec_krb5:
-			pseudoflavor = RPC_AUTH_GSS_KRB5;
-			break;
-		case Opt_sec_krb5i:
-			pseudoflavor = RPC_AUTH_GSS_KRB5I;
-			break;
-		case Opt_sec_krb5p:
-			pseudoflavor = RPC_AUTH_GSS_KRB5P;
-			break;
-		case Opt_sec_lkey:
-			pseudoflavor = RPC_AUTH_GSS_LKEY;
-			break;
-		case Opt_sec_lkeyi:
-			pseudoflavor = RPC_AUTH_GSS_LKEYI;
-			break;
-		case Opt_sec_lkeyp:
-			pseudoflavor = RPC_AUTH_GSS_LKEYP;
-			break;
-		case Opt_sec_spkm:
-			pseudoflavor = RPC_AUTH_GSS_SPKM;
-			break;
-		case Opt_sec_spkmi:
-			pseudoflavor = RPC_AUTH_GSS_SPKMI;
-			break;
-		case Opt_sec_spkmp:
-			pseudoflavor = RPC_AUTH_GSS_SPKMP;
-			break;
-		default:
-			dfprintk(MOUNT,
-				 "NFS: sec= option '%s' not recognized\n", p);
-			return 0;
-		}
-
-		if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
-			return 0;
-	}
-
-	return 1;
-}
-
-static int nfs_parse_version_string(char *string,
-		struct nfs_parsed_mount_data *mnt,
-		substring_t *args)
-{
-	mnt->flags &= ~NFS_MOUNT_VER3;
-	switch (match_token(string, nfs_vers_tokens, args)) {
-	case Opt_vers_2:
-		mnt->version = 2;
-		break;
-	case Opt_vers_3:
-		mnt->flags |= NFS_MOUNT_VER3;
-		mnt->version = 3;
-		break;
-	case Opt_vers_4:
-		/* Backward compatibility option. In future,
-		 * the mount program should always supply
-		 * a NFSv4 minor version number.
-		 */
-		mnt->version = 4;
-		break;
-	case Opt_vers_4_0:
-		mnt->version = 4;
-		mnt->minorversion = 0;
-		break;
-	case Opt_vers_4_1:
-		mnt->version = 4;
-		mnt->minorversion = 1;
-		break;
-	case Opt_vers_4_2:
-		mnt->version = 4;
-		mnt->minorversion = 2;
-		break;
-	default:
-		return 0;
-	}
-	return 1;
-}
-
-static int nfs_get_option_str(substring_t args[], char **option)
-{
-	kfree(*option);
-	*option = match_strdup(args);
-	return !*option;
-}
-
-static int nfs_get_option_ul(substring_t args[], unsigned long *option)
-{
-	int rc;
-	char *string;
-
-	string = match_strdup(args);
-	if (string == NULL)
-		return -ENOMEM;
-	rc = kstrtoul(string, 10, option);
-	kfree(string);
-
-	return rc;
-}
-
-static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
-		unsigned long l_bound, unsigned long u_bound)
-{
-	int ret;
-
-	ret = nfs_get_option_ul(args, option);
-	if (ret != 0)
-		return ret;
-	if (*option < l_bound || *option > u_bound)
-		return -ERANGE;
-	return 0;
-}
-
-/*
- * Error-check and convert a string of mount options from user space into
- * a data structure.  The whole mount string is processed; bad options are
- * skipped as they are encountered.  If there were no errors, return 1;
- * otherwise return 0 (zero).
- */
-static int nfs_parse_mount_options(char *raw,
-				   struct nfs_parsed_mount_data *mnt)
-{
-	char *p, *string, *secdata;
-	int rc, sloppy = 0, invalid_option = 0;
-	unsigned short protofamily = AF_UNSPEC;
-	unsigned short mountfamily = AF_UNSPEC;
-
-	if (!raw) {
-		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
-		return 1;
-	}
-	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
-
-	secdata = alloc_secdata();
-	if (!secdata)
-		goto out_nomem;
-
-	rc = security_sb_copy_data(raw, secdata);
-	if (rc)
-		goto out_security_failure;
-
-	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
-	if (rc)
-		goto out_security_failure;
-
-	free_secdata(secdata);
-
-	while ((p = strsep(&raw, ",")) != NULL) {
-		substring_t args[MAX_OPT_ARGS];
-		unsigned long option;
-		int token;
-
-		if (!*p)
-			continue;
-
-		dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
-
-		token = match_token(p, nfs_mount_option_tokens, args);
-		switch (token) {
-
-		/*
-		 * boolean options:  foo/nofoo
-		 */
-		case Opt_soft:
-			mnt->flags |= NFS_MOUNT_SOFT;
-			break;
-		case Opt_hard:
-			mnt->flags &= ~NFS_MOUNT_SOFT;
-			break;
-		case Opt_posix:
-			mnt->flags |= NFS_MOUNT_POSIX;
-			break;
-		case Opt_noposix:
-			mnt->flags &= ~NFS_MOUNT_POSIX;
-			break;
-		case Opt_cto:
-			mnt->flags &= ~NFS_MOUNT_NOCTO;
-			break;
-		case Opt_nocto:
-			mnt->flags |= NFS_MOUNT_NOCTO;
-			break;
-		case Opt_ac:
-			mnt->flags &= ~NFS_MOUNT_NOAC;
-			break;
-		case Opt_noac:
-			mnt->flags |= NFS_MOUNT_NOAC;
-			break;
-		case Opt_lock:
-			mnt->flags &= ~NFS_MOUNT_NONLM;
-			mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
-					NFS_MOUNT_LOCAL_FCNTL);
-			break;
-		case Opt_nolock:
-			mnt->flags |= NFS_MOUNT_NONLM;
-			mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
-				       NFS_MOUNT_LOCAL_FCNTL);
-			break;
-		case Opt_udp:
-			mnt->flags &= ~NFS_MOUNT_TCP;
-			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-			break;
-		case Opt_tcp:
-			mnt->flags |= NFS_MOUNT_TCP;
-			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-			break;
-		case Opt_rdma:
-			mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
-			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
-			xprt_load_transport(p);
-			break;
-		case Opt_acl:
-			mnt->flags &= ~NFS_MOUNT_NOACL;
-			break;
-		case Opt_noacl:
-			mnt->flags |= NFS_MOUNT_NOACL;
-			break;
-		case Opt_rdirplus:
-			mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
-			break;
-		case Opt_nordirplus:
-			mnt->flags |= NFS_MOUNT_NORDIRPLUS;
-			break;
-		case Opt_sharecache:
-			mnt->flags &= ~NFS_MOUNT_UNSHARED;
-			break;
-		case Opt_nosharecache:
-			mnt->flags |= NFS_MOUNT_UNSHARED;
-			break;
-		case Opt_resvport:
-			mnt->flags &= ~NFS_MOUNT_NORESVPORT;
-			break;
-		case Opt_noresvport:
-			mnt->flags |= NFS_MOUNT_NORESVPORT;
-			break;
-		case Opt_fscache:
-			mnt->options |= NFS_OPTION_FSCACHE;
-			kfree(mnt->fscache_uniq);
-			mnt->fscache_uniq = NULL;
-			break;
-		case Opt_nofscache:
-			mnt->options &= ~NFS_OPTION_FSCACHE;
-			kfree(mnt->fscache_uniq);
-			mnt->fscache_uniq = NULL;
-			break;
-		case Opt_migration:
-			mnt->options |= NFS_OPTION_MIGRATION;
-			break;
-		case Opt_nomigration:
-			mnt->options &= NFS_OPTION_MIGRATION;
-			break;
-
-		/*
-		 * options that take numeric values
-		 */
-		case Opt_port:
-			if (nfs_get_option_ul(args, &option) ||
-			    option > USHRT_MAX)
-				goto out_invalid_value;
-			mnt->nfs_server.port = option;
-			break;
-		case Opt_rsize:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->rsize = option;
-			break;
-		case Opt_wsize:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->wsize = option;
-			break;
-		case Opt_bsize:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->bsize = option;
-			break;
-		case Opt_timeo:
-			if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
-				goto out_invalid_value;
-			mnt->timeo = option;
-			break;
-		case Opt_retrans:
-			if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
-				goto out_invalid_value;
-			mnt->retrans = option;
-			break;
-		case Opt_acregmin:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->acregmin = option;
-			break;
-		case Opt_acregmax:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->acregmax = option;
-			break;
-		case Opt_acdirmin:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->acdirmin = option;
-			break;
-		case Opt_acdirmax:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->acdirmax = option;
-			break;
-		case Opt_actimeo:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->acregmin = mnt->acregmax =
-			mnt->acdirmin = mnt->acdirmax = option;
-			break;
-		case Opt_namelen:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			mnt->namlen = option;
-			break;
-		case Opt_mountport:
-			if (nfs_get_option_ul(args, &option) ||
-			    option > USHRT_MAX)
-				goto out_invalid_value;
-			mnt->mount_server.port = option;
-			break;
-		case Opt_mountvers:
-			if (nfs_get_option_ul(args, &option) ||
-			    option < NFS_MNT_VERSION ||
-			    option > NFS_MNT3_VERSION)
-				goto out_invalid_value;
-			mnt->mount_server.version = option;
-			break;
-		case Opt_minorversion:
-			if (nfs_get_option_ul(args, &option))
-				goto out_invalid_value;
-			if (option > NFS4_MAX_MINOR_VERSION)
-				goto out_invalid_value;
-			mnt->minorversion = option;
-			break;
-
-		/*
-		 * options that take text values
-		 */
-		case Opt_nfsvers:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			rc = nfs_parse_version_string(string, mnt, args);
-			kfree(string);
-			if (!rc)
-				goto out_invalid_value;
-			break;
-		case Opt_sec:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			rc = nfs_parse_security_flavors(string, mnt);
-			kfree(string);
-			if (!rc) {
-				dfprintk(MOUNT, "NFS:   unrecognized "
-						"security flavor\n");
-				return 0;
-			}
-			break;
-		case Opt_proto:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			token = match_token(string,
-					    nfs_xprt_protocol_tokens, args);
-
-			protofamily = AF_INET;
-			switch (token) {
-			case Opt_xprt_udp6:
-				protofamily = AF_INET6;
-			case Opt_xprt_udp:
-				mnt->flags &= ~NFS_MOUNT_TCP;
-				mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-				break;
-			case Opt_xprt_tcp6:
-				protofamily = AF_INET6;
-			case Opt_xprt_tcp:
-				mnt->flags |= NFS_MOUNT_TCP;
-				mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
-				break;
-			case Opt_xprt_rdma6:
-				protofamily = AF_INET6;
-			case Opt_xprt_rdma:
-				/* vector side protocols to TCP */
-				mnt->flags |= NFS_MOUNT_TCP;
-				mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
-				xprt_load_transport(string);
-				break;
-			default:
-				dfprintk(MOUNT, "NFS:   unrecognized "
-						"transport protocol\n");
-				kfree(string);
-				return 0;
-			}
-			kfree(string);
-			break;
-		case Opt_mountproto:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			token = match_token(string,
-					    nfs_xprt_protocol_tokens, args);
-			kfree(string);
-
-			mountfamily = AF_INET;
-			switch (token) {
-			case Opt_xprt_udp6:
-				mountfamily = AF_INET6;
-			case Opt_xprt_udp:
-				mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
-				break;
-			case Opt_xprt_tcp6:
-				mountfamily = AF_INET6;
-			case Opt_xprt_tcp:
-				mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
-				break;
-			case Opt_xprt_rdma: /* not used for side protocols */
-			default:
-				dfprintk(MOUNT, "NFS:   unrecognized "
-						"transport protocol\n");
-				return 0;
-			}
-			break;
-		case Opt_addr:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			mnt->nfs_server.addrlen =
-				rpc_pton(mnt->net, string, strlen(string),
-					(struct sockaddr *)
-					&mnt->nfs_server.address,
-					sizeof(mnt->nfs_server.address));
-			kfree(string);
-			if (mnt->nfs_server.addrlen == 0)
-				goto out_invalid_address;
-			break;
-		case Opt_clientaddr:
-			if (nfs_get_option_str(args, &mnt->client_address))
-				goto out_nomem;
-			break;
-		case Opt_mounthost:
-			if (nfs_get_option_str(args,
-					       &mnt->mount_server.hostname))
-				goto out_nomem;
-			break;
-		case Opt_mountaddr:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			mnt->mount_server.addrlen =
-				rpc_pton(mnt->net, string, strlen(string),
-					(struct sockaddr *)
-					&mnt->mount_server.address,
-					sizeof(mnt->mount_server.address));
-			kfree(string);
-			if (mnt->mount_server.addrlen == 0)
-				goto out_invalid_address;
-			break;
-		case Opt_lookupcache:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			token = match_token(string,
-					nfs_lookupcache_tokens, args);
-			kfree(string);
-			switch (token) {
-				case Opt_lookupcache_all:
-					mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
-					break;
-				case Opt_lookupcache_positive:
-					mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
-					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
-					break;
-				case Opt_lookupcache_none:
-					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
-					break;
-				default:
-					dfprintk(MOUNT, "NFS:   invalid "
-							"lookupcache argument\n");
-					return 0;
-			};
-			break;
-		case Opt_fscache_uniq:
-			if (nfs_get_option_str(args, &mnt->fscache_uniq))
-				goto out_nomem;
-			mnt->options |= NFS_OPTION_FSCACHE;
-			break;
-		case Opt_local_lock:
-			string = match_strdup(args);
-			if (string == NULL)
-				goto out_nomem;
-			token = match_token(string, nfs_local_lock_tokens,
-					args);
-			kfree(string);
-			switch (token) {
-			case Opt_local_lock_all:
-				mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
-					       NFS_MOUNT_LOCAL_FCNTL);
-				break;
-			case Opt_local_lock_flock:
-				mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
-				break;
-			case Opt_local_lock_posix:
-				mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
-				break;
-			case Opt_local_lock_none:
-				mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
-						NFS_MOUNT_LOCAL_FCNTL);
-				break;
-			default:
-				dfprintk(MOUNT, "NFS:	invalid	"
-						"local_lock argument\n");
-				return 0;
-			};
-			break;
-
-		/*
-		 * Special options
-		 */
-		case Opt_sloppy:
-			sloppy = 1;
-			dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
-			break;
-		case Opt_userspace:
-		case Opt_deprecated:
-			dfprintk(MOUNT, "NFS:   ignoring mount option "
-					"'%s'\n", p);
-			break;
-
-		default:
-			invalid_option = 1;
-			dfprintk(MOUNT, "NFS:   unrecognized mount option "
-					"'%s'\n", p);
-		}
-	}
-
-	if (!sloppy && invalid_option)
-		return 0;
-
-	if (mnt->minorversion && mnt->version != 4)
-		goto out_minorversion_mismatch;
-
-	if (mnt->options & NFS_OPTION_MIGRATION &&
-	    (mnt->version != 4 || mnt->minorversion != 0))
-		goto out_migration_misuse;
-
-	/*
-	 * verify that any proto=/mountproto= options match the address
-	 * families in the addr=/mountaddr= options.
-	 */
-	if (protofamily != AF_UNSPEC &&
-	    protofamily != mnt->nfs_server.address.ss_family)
-		goto out_proto_mismatch;
-
-	if (mountfamily != AF_UNSPEC) {
-		if (mnt->mount_server.addrlen) {
-			if (mountfamily != mnt->mount_server.address.ss_family)
-				goto out_mountproto_mismatch;
-		} else {
-			if (mountfamily != mnt->nfs_server.address.ss_family)
-				goto out_mountproto_mismatch;
-		}
-	}
-
-	return 1;
-
-out_mountproto_mismatch:
-	printk(KERN_INFO "NFS: mount server address does not match mountproto= "
-			 "option\n");
-	return 0;
-out_proto_mismatch:
-	printk(KERN_INFO "NFS: server address does not match proto= option\n");
-	return 0;
-out_invalid_address:
-	printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
-	return 0;
-out_invalid_value:
-	printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
-	return 0;
-out_minorversion_mismatch:
-	printk(KERN_INFO "NFS: mount option vers=%u does not support "
-			 "minorversion=%u\n", mnt->version, mnt->minorversion);
-	return 0;
-out_migration_misuse:
-	printk(KERN_INFO
-		"NFS: 'migration' not supported for this NFS version\n");
-	return 0;
-out_nomem:
-	printk(KERN_INFO "NFS: not enough memory to parse option\n");
-	return 0;
-out_security_failure:
-	free_secdata(secdata);
-	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
-	return 0;
-}
-
-/*
  * Ensure that a specified authtype in args->auth_info is supported by
  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
  * -EACCES if not.
  */
-static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
+static int nfs_verify_authflavors(struct nfs_mount_context *args,
 			rpc_authflavor_t *server_authlist, unsigned int count)
 {
 	rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
@@ -1731,7 +726,7 @@ static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
  * Use the remote server's MOUNT service to request the NFS file handle
  * corresponding to the provided path.
  */
-static int nfs_request_mount(struct nfs_parsed_mount_data *args,
+static int nfs_request_mount(struct nfs_mount_context *args,
 			     struct nfs_fh *root_fh,
 			     rpc_authflavor_t *server_authlist,
 			     unsigned int *server_authlist_len)
@@ -1745,7 +740,7 @@ static int nfs_request_mount(struct nfs_parsed_mount_data *args,
 		.noresvport	= args->flags & NFS_MOUNT_NORESVPORT,
 		.auth_flav_len	= server_authlist_len,
 		.auth_flavs	= server_authlist,
-		.net		= args->net,
+		.net		= args->mc.net_ns,
 	};
 	int status;
 
@@ -1768,7 +763,7 @@ static int nfs_request_mount(struct nfs_parsed_mount_data *args,
 	/*
 	 * Construct the mount server's address.
 	 */
-	if (args->mount_server.address.ss_family == AF_UNSPEC) {
+	if (args->mount_server.address.sa_family == AF_UNSPEC) {
 		memcpy(request.sap, &args->nfs_server.address,
 		       args->nfs_server.addrlen);
 		args->mount_server.addrlen = args->nfs_server.addrlen;
@@ -1790,20 +785,17 @@ static int nfs_request_mount(struct nfs_parsed_mount_data *args,
 	return 0;
 }
 
-static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
-					struct nfs_subversion *nfs_mod)
+static struct nfs_server *nfs_try_mount_request(struct nfs_mount_context *ctx)
 {
 	int status;
 	unsigned int i;
 	bool tried_auth_unix = false;
 	bool auth_null_in_list = false;
 	struct nfs_server *server = ERR_PTR(-EACCES);
-	struct nfs_parsed_mount_data *args = mount_info->parsed;
 	rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
 	unsigned int authlist_len = ARRAY_SIZE(authlist);
 
-	status = nfs_request_mount(args, mount_info->mntfh, authlist,
-					&authlist_len);
+	status = nfs_request_mount(ctx, ctx->mntfh, authlist, &authlist_len);
 	if (status)
 		return ERR_PTR(status);
 
@@ -1811,13 +803,13 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 	 * Was a sec= authflavor specified in the options? First, verify
 	 * whether the server supports it, and then just try to use it if so.
 	 */
-	if (args->auth_info.flavor_len > 0) {
-		status = nfs_verify_authflavors(args, authlist, authlist_len);
+	if (ctx->auth_info.flavor_len > 0) {
+		status = nfs_verify_authflavors(ctx, authlist, authlist_len);
 		dfprintk(MOUNT, "NFS: using auth flavor %u\n",
-			 args->selected_flavor);
+			 ctx->selected_flavor);
 		if (status)
 			return ERR_PTR(status);
-		return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
+		return ctx->nfs_mod->rpc_ops->create_server(ctx);
 	}
 
 	/*
@@ -1843,8 +835,8 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 			/* Fallthrough */
 		}
 		dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
-		args->selected_flavor = flavor;
-		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
+		ctx->selected_flavor = flavor;
+		server = ctx->nfs_mod->rpc_ops->create_server(ctx);
 		if (!IS_ERR(server))
 			return server;
 	}
@@ -1859,338 +851,30 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
 
 	/* Last chance! Try AUTH_UNIX */
 	dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
-	args->selected_flavor = RPC_AUTH_UNIX;
-	return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
+	ctx->selected_flavor = RPC_AUTH_UNIX;
+	return ctx->nfs_mod->rpc_ops->create_server(ctx);
 }
 
-struct dentry *nfs_try_mount(int flags, const char *dev_name,
-			     struct nfs_mount_info *mount_info,
-			     struct nfs_subversion *nfs_mod)
+struct dentry *nfs_try_mount(struct nfs_mount_context *ctx)
 {
 	struct nfs_server *server;
 
-	if (mount_info->parsed->need_mount)
-		server = nfs_try_mount_request(mount_info, nfs_mod);
+	pr_notice("*** nfs_try_mount\n");
+
+	if (ctx->need_mount)
+		server = nfs_try_mount_request(ctx);
 	else
-		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
+		server = ctx->nfs_mod->rpc_ops->create_server(ctx);
 
-	if (IS_ERR(server))
+	if (IS_ERR(server)) {
+		ctx->mc.error = "NFS: Couldn't create server";
 		return ERR_CAST(server);
-
-	return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
-}
-EXPORT_SYMBOL_GPL(nfs_try_mount);
-
-/*
- * Split "dev_name" into "hostname:export_path".
- *
- * The leftmost colon demarks the split between the server's hostname
- * and the export path.  If the hostname starts with a left square
- * bracket, then it may contain colons.
- *
- * Note: caller frees hostname and export path, even on error.
- */
-static int nfs_parse_devname(const char *dev_name,
-			     char **hostname, size_t maxnamlen,
-			     char **export_path, size_t maxpathlen)
-{
-	size_t len;
-	char *end;
-
-	/* Is the host name protected with square brakcets? */
-	if (*dev_name == '[') {
-		end = strchr(++dev_name, ']');
-		if (end == NULL || end[1] != ':')
-			goto out_bad_devname;
-
-		len = end - dev_name;
-		end++;
-	} else {
-		char *comma;
-
-		end = strchr(dev_name, ':');
-		if (end == NULL)
-			goto out_bad_devname;
-		len = end - dev_name;
-
-		/* kill possible hostname list: not supported */
-		comma = strchr(dev_name, ',');
-		if (comma != NULL && comma < end)
-			*comma = 0;
 	}
 
-	if (len > maxnamlen)
-		goto out_hostname;
-
-	/* N.B. caller will free nfs_server.hostname in all cases */
-	*hostname = kstrndup(dev_name, len, GFP_KERNEL);
-	if (*hostname == NULL)
-		goto out_nomem;
-	len = strlen(++end);
-	if (len > maxpathlen)
-		goto out_path;
-	*export_path = kstrndup(end, len, GFP_KERNEL);
-	if (!*export_path)
-		goto out_nomem;
-
-	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
-	return 0;
-
-out_bad_devname:
-	dfprintk(MOUNT, "NFS: device name not in host:path format\n");
-	return -EINVAL;
-
-out_nomem:
-	dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
-	return -ENOMEM;
-
-out_hostname:
-	dfprintk(MOUNT, "NFS: server hostname too long\n");
-	return -ENAMETOOLONG;
-
-out_path:
-	dfprintk(MOUNT, "NFS: export pathname too long\n");
-	return -ENAMETOOLONG;
+	return nfs_fs_mount_common(server, ctx);
 }
+EXPORT_SYMBOL_GPL(nfs_try_mount);
 
-/*
- * Validate the NFS2/NFS3 mount data
- * - fills in the mount root filehandle
- *
- * For option strings, user space handles the following behaviors:
- *
- * + DNS: mapping server host name to IP address ("addr=" option)
- *
- * + failure mode: how to behave if a mount request can't be handled
- *   immediately ("fg/bg" option)
- *
- * + retry: how often to retry a mount request ("retry=" option)
- *
- * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
- *   mountproto=tcp after mountproto=udp, and so on
- */
-static int nfs23_validate_mount_data(void *options,
-				     struct nfs_parsed_mount_data *args,
-				     struct nfs_fh *mntfh,
-				     const char *dev_name)
-{
-	struct nfs_mount_data *data = (struct nfs_mount_data *)options;
-	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
-	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
-
-	if (data == NULL)
-		goto out_no_data;
-
-	args->version = NFS_DEFAULT_VERSION;
-	switch (data->version) {
-	case 1:
-		data->namlen = 0;
-	case 2:
-		data->bsize = 0;
-	case 3:
-		if (data->flags & NFS_MOUNT_VER3)
-			goto out_no_v3;
-		data->root.size = NFS2_FHSIZE;
-		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
-		/* Turn off security negotiation */
-		extra_flags |= NFS_MOUNT_SECFLAVOUR;
-	case 4:
-		if (data->flags & NFS_MOUNT_SECFLAVOUR)
-			goto out_no_sec;
-	case 5:
-		memset(data->context, 0, sizeof(data->context));
-	case 6:
-		if (data->flags & NFS_MOUNT_VER3) {
-			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
-				goto out_invalid_fh;
-			mntfh->size = data->root.size;
-			args->version = 3;
-		} else {
-			mntfh->size = NFS2_FHSIZE;
-			args->version = 2;
-		}
-
-
-		memcpy(mntfh->data, data->root.data, mntfh->size);
-		if (mntfh->size < sizeof(mntfh->data))
-			memset(mntfh->data + mntfh->size, 0,
-			       sizeof(mntfh->data) - mntfh->size);
-
-		/*
-		 * Translate to nfs_parsed_mount_data, which nfs_fill_super
-		 * can deal with.
-		 */
-		args->flags		= data->flags & NFS_MOUNT_FLAGMASK;
-		args->flags		|= extra_flags;
-		args->rsize		= data->rsize;
-		args->wsize		= data->wsize;
-		args->timeo		= data->timeo;
-		args->retrans		= data->retrans;
-		args->acregmin		= data->acregmin;
-		args->acregmax		= data->acregmax;
-		args->acdirmin		= data->acdirmin;
-		args->acdirmax		= data->acdirmax;
-		args->need_mount	= false;
-
-		memcpy(sap, &data->addr, sizeof(data->addr));
-		args->nfs_server.addrlen = sizeof(data->addr);
-		args->nfs_server.port = ntohs(data->addr.sin_port);
-		if (!nfs_verify_server_address(sap))
-			goto out_no_address;
-
-		if (!(data->flags & NFS_MOUNT_TCP))
-			args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-		/* N.B. caller will free nfs_server.hostname in all cases */
-		args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
-		args->namlen		= data->namlen;
-		args->bsize		= data->bsize;
-
-		if (data->flags & NFS_MOUNT_SECFLAVOUR)
-			args->selected_flavor = data->pseudoflavor;
-		else
-			args->selected_flavor = RPC_AUTH_UNIX;
-		if (!args->nfs_server.hostname)
-			goto out_nomem;
-
-		if (!(data->flags & NFS_MOUNT_NONLM))
-			args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
-					 NFS_MOUNT_LOCAL_FCNTL);
-		else
-			args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
-					NFS_MOUNT_LOCAL_FCNTL);
-		/*
-		 * The legacy version 6 binary mount data from userspace has a
-		 * field used only to transport selinux information into the
-		 * the kernel.  To continue to support that functionality we
-		 * have a touch of selinux knowledge here in the NFS code. The
-		 * userspace code converted context=blah to just blah so we are
-		 * converting back to the full string selinux understands.
-		 */
-		if (data->context[0]){
-#ifdef CONFIG_SECURITY_SELINUX
-			int rc;
-			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
-			if (!opts_str)
-				return -ENOMEM;
-			strcpy(opts_str, "context=");
-			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
-			strcat(opts_str, &data->context[0]);
-			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
-			kfree(opts_str);
-			if (rc)
-				return rc;
-#else
-			return -EINVAL;
-#endif
-		}
-
-		break;
-	default:
-		return NFS_TEXT_DATA;
-	}
-
-	return 0;
-
-out_no_data:
-	dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
-	return -EINVAL;
-
-out_no_v3:
-	dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
-		 data->version);
-	return -EINVAL;
-
-out_no_sec:
-	dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
-	return -EINVAL;
-
-out_nomem:
-	dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
-	return -ENOMEM;
-
-out_no_address:
-	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
-	return -EINVAL;
-
-out_invalid_fh:
-	dfprintk(MOUNT, "NFS: invalid root filehandle\n");
-	return -EINVAL;
-}
-
-#if IS_ENABLED(CONFIG_NFS_V4)
-static int nfs_validate_mount_data(struct file_system_type *fs_type,
-				   void *options,
-				   struct nfs_parsed_mount_data *args,
-				   struct nfs_fh *mntfh,
-				   const char *dev_name)
-{
-	if (fs_type == &nfs_fs_type)
-		return nfs23_validate_mount_data(options, args, mntfh, dev_name);
-	return nfs4_validate_mount_data(options, args, dev_name);
-}
-#else
-static int nfs_validate_mount_data(struct file_system_type *fs_type,
-				   void *options,
-				   struct nfs_parsed_mount_data *args,
-				   struct nfs_fh *mntfh,
-				   const char *dev_name)
-{
-	return nfs23_validate_mount_data(options, args, mntfh, dev_name);
-}
-#endif
-
-static int nfs_validate_text_mount_data(void *options,
-					struct nfs_parsed_mount_data *args,
-					const char *dev_name)
-{
-	int port = 0;
-	int max_namelen = PAGE_SIZE;
-	int max_pathlen = NFS_MAXPATHLEN;
-	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
-
-	if (nfs_parse_mount_options((char *)options, args) == 0)
-		return -EINVAL;
-
-	if (!nfs_verify_server_address(sap))
-		goto out_no_address;
-
-	if (args->version == 4) {
-#if IS_ENABLED(CONFIG_NFS_V4)
-		port = NFS_PORT;
-		max_namelen = NFS4_MAXNAMLEN;
-		max_pathlen = NFS4_MAXPATHLEN;
-		nfs_validate_transport_protocol(args);
-		if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
-			goto out_invalid_transport_udp;
-		nfs4_validate_mount_flags(args);
-#else
-		goto out_v4_not_compiled;
-#endif /* CONFIG_NFS_V4 */
-	} else
-		nfs_set_mount_transport_protocol(args);
-
-	nfs_set_port(sap, &args->nfs_server.port, port);
-
-	return nfs_parse_devname(dev_name,
-				   &args->nfs_server.hostname,
-				   max_namelen,
-				   &args->nfs_server.export_path,
-				   max_pathlen);
-
-#if !IS_ENABLED(CONFIG_NFS_V4)
-out_v4_not_compiled:
-	dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
-	return -EPROTONOSUPPORT;
-#else
-out_invalid_transport_udp:
-	dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
-	return -EINVAL;
-#endif /* !CONFIG_NFS_V4 */
-
-out_no_address:
-	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
-	return -EINVAL;
-}
 
 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
 		| NFS_MOUNT_SECURE \
@@ -2207,7 +891,7 @@ static int nfs_validate_text_mount_data(void *options,
 
 static int
 nfs_compare_remount_data(struct nfs_server *nfss,
-			 struct nfs_parsed_mount_data *data)
+			 struct nfs_mount_context *data)
 {
 	if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
 	    data->rsize != nfss->rsize ||
@@ -2230,15 +914,11 @@ nfs_compare_remount_data(struct nfs_server *nfss,
 	return 0;
 }
 
-int
-nfs_remount(struct super_block *sb, int *flags, char *raw_data)
+int nfs_remount(struct super_block *sb, struct mount_context *mc)
 {
-	int error;
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
 	struct nfs_server *nfss = sb->s_fs_info;
-	struct nfs_parsed_mount_data *data;
-	struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
-	struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
-	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
 
 	sync_filesystem(sb);
 
@@ -2248,60 +928,27 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 	 * ones were explicitly specified. Fall back to legacy behavior and
 	 * just return success.
 	 */
-	if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
-	    (nfsvers <= 3 && (!options || (options->version >= 1 &&
-					   options->version <= 6))))
+	if (ctx->skip_remount_option_check)
 		return 0;
 
-	data = kzalloc(sizeof(*data), GFP_KERNEL);
-	if (data == NULL)
-		return -ENOMEM;
-
-	/* fill out struct with values from existing mount */
-	data->flags = nfss->flags;
-	data->rsize = nfss->rsize;
-	data->wsize = nfss->wsize;
-	data->retrans = nfss->client->cl_timeout->to_retries;
-	data->selected_flavor = nfss->client->cl_auth->au_flavor;
-	data->acregmin = nfss->acregmin / HZ;
-	data->acregmax = nfss->acregmax / HZ;
-	data->acdirmin = nfss->acdirmin / HZ;
-	data->acdirmax = nfss->acdirmax / HZ;
-	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
-	data->nfs_server.port = nfss->port;
-	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
-	data->version = nfsvers;
-	data->minorversion = nfss->nfs_client->cl_minorversion;
-	data->net = current->nsproxy->net_ns;
-	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
-		data->nfs_server.addrlen);
-
-	/* overwrite those values with any that were specified */
-	error = -EINVAL;
-	if (!nfs_parse_mount_options((char *)options, data))
-		goto out;
-
 	/*
 	 * noac is a special case. It implies -o sync, but that's not
 	 * necessarily reflected in the mtab options. do_remount_sb
 	 * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
 	 * remount options, so we have to explicitly reset it.
 	 */
-	if (data->flags & NFS_MOUNT_NOAC)
-		*flags |= MS_SYNCHRONOUS;
+	if (ctx->flags & NFS_MOUNT_NOAC)
+		ctx->mc.ms_flags |= MS_SYNCHRONOUS;
 
 	/* compare new mount options with old ones */
-	error = nfs_compare_remount_data(nfss, data);
-out:
-	kfree(data);
-	return error;
+	return nfs_compare_remount_data(nfss, ctx);
 }
 EXPORT_SYMBOL_GPL(nfs_remount);
 
 /*
  * Initialise the common bits of the superblock
  */
-inline void nfs_initialise_sb(struct super_block *sb)
+static inline void nfs_initialise_sb(struct super_block *sb)
 {
 	struct nfs_server *server = NFS_SB(sb);
 
@@ -2319,69 +966,75 @@ inline void nfs_initialise_sb(struct super_block *sb)
 }
 
 /*
- * Finish setting up an NFS2/3 superblock
+ * Finish setting up a cloned NFS2/3/4 superblock
  */
-int nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
+static int nfs_clone_super(struct super_block *sb, struct mount_context *mc)
 {
-	struct nfs_parsed_mount_data *data = mount_info->parsed;
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
+	const struct super_block *old_sb = ctx->clone_data.sb;
 	struct nfs_server *server = NFS_SB(sb);
-	int ret;
 
-	sb->s_blocksize_bits = 0;
-	sb->s_blocksize = 0;
-	sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
-	sb->s_op = server->nfs_client->cl_nfs_mod->sops;
-	if (data && data->bsize)
-		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
+	sb->s_blocksize_bits = old_sb->s_blocksize_bits;
+	sb->s_blocksize = old_sb->s_blocksize;
+	sb->s_maxbytes = old_sb->s_maxbytes;
+	sb->s_xattr = old_sb->s_xattr;
+	sb->s_op = old_sb->s_op;
+	sb->s_time_gran = 1;
 
 	if (server->nfs_client->rpc_ops->version != 2) {
 		/* The VFS shouldn't apply the umask to mode bits. We will do
 		 * so ourselves when necessary.
 		 */
 		sb->s_flags |= MS_POSIXACL;
-		sb->s_time_gran = 1;
 	}
 
  	nfs_initialise_sb(sb);
 
-	ret = super_setup_bdi_name(sb, "%u:%u", MAJOR(server->s_dev),
-				   MINOR(server->s_dev));
-	if (ret)
-		return ret;
-	sb->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
-	return 0;
+	sb->s_bdi = bdi_get(old_sb->s_bdi);
 
+	return 0;
 }
-EXPORT_SYMBOL_GPL(nfs_fill_super);
 
 /*
- * Finish setting up a cloned NFS2/3/4 superblock
+ * Finish setting up an NFS2/3 superblock
  */
-int nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
+int nfs_fill_super(struct super_block *sb, struct mount_context *mc)
 {
-	const struct super_block *old_sb = mount_info->cloned->sb;
+	struct nfs_mount_context *ctx =
+		container_of(mc, struct nfs_mount_context, mc);
 	struct nfs_server *server = NFS_SB(sb);
+	int ret;
 
-	sb->s_blocksize_bits = old_sb->s_blocksize_bits;
-	sb->s_blocksize = old_sb->s_blocksize;
-	sb->s_maxbytes = old_sb->s_maxbytes;
-	sb->s_xattr = old_sb->s_xattr;
-	sb->s_op = old_sb->s_op;
-	sb->s_time_gran = 1;
+	if (ctx->clone_data.sb)
+		return nfs_clone_super(sb, mc);
+	
+	sb->s_blocksize_bits = 0;
+	sb->s_blocksize = 0;
+	sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
+	sb->s_op = server->nfs_client->cl_nfs_mod->sops;
+	if (ctx->bsize)
+		sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits);
 
 	if (server->nfs_client->rpc_ops->version != 2) {
 		/* The VFS shouldn't apply the umask to mode bits. We will do
 		 * so ourselves when necessary.
 		 */
 		sb->s_flags |= MS_POSIXACL;
+		sb->s_time_gran = 1;
 	}
 
  	nfs_initialise_sb(sb);
 
-	sb->s_bdi = bdi_get(old_sb->s_bdi);
-
+	ret = super_setup_bdi_name(sb, "%u:%u", MAJOR(server->s_dev),
+				   MINOR(server->s_dev));
+	if (ret)
+		return ret;
+	sb->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
 	return 0;
+
 }
+EXPORT_SYMBOL_GPL(nfs_fill_super);
 
 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
 {
@@ -2495,8 +1148,7 @@ static int nfs_compare_super(struct super_block *sb, void *data)
 
 #ifdef CONFIG_NFS_FSCACHE
 static void nfs_get_cache_cookie(struct super_block *sb,
-				 struct nfs_parsed_mount_data *parsed,
-				 struct nfs_clone_mount *cloned)
+				 struct nfs_mount_context *ctx)
 {
 	struct nfs_server *nfss = NFS_SB(sb);
 	char *uniq = NULL;
@@ -2505,21 +1157,21 @@ static void nfs_get_cache_cookie(struct super_block *sb,
 	nfss->fscache_key = NULL;
 	nfss->fscache = NULL;
 
-	if (parsed) {
-		if (!(parsed->options & NFS_OPTION_FSCACHE))
+	if (ctx) {
+		if (!(ctx->options & NFS_OPTION_FSCACHE))
 			return;
-		if (parsed->fscache_uniq) {
-			uniq = parsed->fscache_uniq;
-			ulen = strlen(parsed->fscache_uniq);
+		if (ctx->fscache_uniq) {
+			uniq = ctx->fscache_uniq;
+			ulen = strlen(ctx->fscache_uniq);
 		}
-	} else if (cloned) {
-		struct nfs_server *mnt_s = NFS_SB(cloned->sb);
+	} else if (ctx->clone_data.cloned) {
+		struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
 		if (!(mnt_s->options & NFS_OPTION_FSCACHE))
 			return;
 		if (mnt_s->fscache_key) {
 			uniq = mnt_s->fscache_key->key.uniquifier;
 			ulen = mnt_s->fscache_key->key.uniq_len;
-		};
+		}
 	} else
 		return;
 
@@ -2527,22 +1179,22 @@ static void nfs_get_cache_cookie(struct super_block *sb,
 }
 #else
 static void nfs_get_cache_cookie(struct super_block *sb,
-				 struct nfs_parsed_mount_data *parsed,
-				 struct nfs_clone_mount *cloned)
+				 struct nfs_mount_context *ctx)
 {
 }
 #endif
 
 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
-			struct nfs_mount_info *mount_info)
+			struct nfs_mount_context *ctx)
 {
 	int error;
 	unsigned long kflags = 0, kflags_out = 0;
+
 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
 		kflags |= SECURITY_LSM_NATIVE_LABELS;
 
-	error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
-						kflags, &kflags_out);
+	error = security_sb_set_mnt_opts(s, ctx->mc.security,
+					 kflags, &kflags_out);
 	if (error)
 		goto err;
 
@@ -2555,25 +1207,23 @@ int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
 
 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
-			  struct nfs_mount_info *mount_info)
+			  struct nfs_mount_context *ctx)
 {
 	/* clone any lsm security options from the parent to the new sb */
 	if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
 		return -ESTALE;
-	return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
+	return security_sb_clone_mnt_opts(ctx->clone_data.sb, s);
 }
 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
 
 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
-				   int flags, const char *dev_name,
-				   struct nfs_mount_info *mount_info,
-				   struct nfs_subversion *nfs_mod)
+				   struct nfs_mount_context *ctx)
 {
 	struct super_block *s;
 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
 	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
 	struct nfs_sb_mountdata sb_mntdata = {
-		.mntflags = flags,
+		.mntflags = ctx->mc.ms_flags,
 		.server = server,
 	};
 	int error;
@@ -2585,14 +1235,16 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server,
 	if (server->flags & NFS_MOUNT_NOAC)
 		sb_mntdata.mntflags |= MS_SYNCHRONOUS;
 
-	if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
-		if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
+	if (ctx->clone_data.cloned && ctx->clone_data.sb != NULL)
+		if (ctx->clone_data.sb->s_flags & MS_SYNCHRONOUS)
 			sb_mntdata.mntflags |= MS_SYNCHRONOUS;
 
 	/* Get a superblock - note that we may end up sharing one that already exists */
-	s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
+	s = sget(ctx->nfs_mod->nfs_fs, compare_super, nfs_set_super, ctx->mc.ms_flags,
+		 &sb_mntdata);
 	if (IS_ERR(s)) {
 		mntroot = ERR_CAST(s);
+		ctx->mc.error = "NFS: Couldn't get superblock";
 		goto out_err_nosb;
 	}
 
@@ -2605,17 +1257,17 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server,
 
 	if (!s->s_root) {
 		/* initial superblock/root creation */
-		error = mount_info->fill_super(s, mount_info);
-		if (error)
-			goto error_splat_super;
-		nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
+		ctx->mc.ops->fill_super(s, &ctx->mc);
+		nfs_get_cache_cookie(s, ctx);
 	}
 
-	mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
-	if (IS_ERR(mntroot))
+	mntroot = nfs_get_root(s, ctx->mntfh, ctx->mc.device);
+	if (IS_ERR(mntroot)) {
+		ctx->mc.error = "NFS: Couldn't get root dentry";
 		goto error_splat_super;
+	}
 
-	error = mount_info->set_security(s, mntroot, mount_info);
+	error = ctx->set_security(s, mntroot, ctx);
 	if (error)
 		goto error_splat_root;
 
@@ -2637,47 +1289,6 @@ struct dentry *nfs_fs_mount_common(struct nfs_server *server,
 }
 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
 
-struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
-	int flags, const char *dev_name, void *raw_data)
-{
-	struct nfs_mount_info mount_info = {
-		.fill_super = nfs_fill_super,
-		.set_security = nfs_set_sb_security,
-	};
-	struct dentry *mntroot = ERR_PTR(-ENOMEM);
-	struct nfs_subversion *nfs_mod;
-	int error;
-
-	mount_info.parsed = nfs_alloc_parsed_mount_data();
-	mount_info.mntfh = nfs_alloc_fhandle();
-	if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
-		goto out;
-
-	/* Validate the mount data */
-	error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
-	if (error == NFS_TEXT_DATA)
-		error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
-	if (error < 0) {
-		mntroot = ERR_PTR(error);
-		goto out;
-	}
-
-	nfs_mod = get_nfs_version(mount_info.parsed->version);
-	if (IS_ERR(nfs_mod)) {
-		mntroot = ERR_CAST(nfs_mod);
-		goto out;
-	}
-
-	mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
-
-	put_nfs_version(nfs_mod);
-out:
-	nfs_free_parsed_mount_data(mount_info.parsed);
-	nfs_free_fhandle(mount_info.mntfh);
-	return mntroot;
-}
-EXPORT_SYMBOL_GPL(nfs_fs_mount);
-
 /*
  * Destroy an NFS2/3 superblock
  */
@@ -2695,150 +1306,8 @@ void nfs_kill_super(struct super_block *s)
 }
 EXPORT_SYMBOL_GPL(nfs_kill_super);
 
-/*
- * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
- */
-static struct dentry *
-nfs_xdev_mount(struct file_system_type *fs_type, int flags,
-		const char *dev_name, void *raw_data)
-{
-	struct nfs_clone_mount *data = raw_data;
-	struct nfs_mount_info mount_info = {
-		.fill_super = nfs_clone_super,
-		.set_security = nfs_clone_sb_security,
-		.cloned = data,
-	};
-	struct nfs_server *server;
-	struct dentry *mntroot = ERR_PTR(-ENOMEM);
-	struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
-
-	dprintk("--> nfs_xdev_mount()\n");
-
-	mount_info.mntfh = mount_info.cloned->fh;
-
-	/* create a new volume representation */
-	server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
-
-	if (IS_ERR(server))
-		mntroot = ERR_CAST(server);
-	else
-		mntroot = nfs_fs_mount_common(server, flags,
-				dev_name, &mount_info, nfs_mod);
-
-	dprintk("<-- nfs_xdev_mount() = %ld\n",
-			IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
-	return mntroot;
-}
-
 #if IS_ENABLED(CONFIG_NFS_V4)
 
-static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
-{
-	args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
-			 NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
-}
-
-/*
- * Validate NFSv4 mount options
- */
-static int nfs4_validate_mount_data(void *options,
-				    struct nfs_parsed_mount_data *args,
-				    const char *dev_name)
-{
-	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
-	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
-	char *c;
-
-	if (data == NULL)
-		goto out_no_data;
-
-	args->version = 4;
-
-	switch (data->version) {
-	case 1:
-		if (data->host_addrlen > sizeof(args->nfs_server.address))
-			goto out_no_address;
-		if (data->host_addrlen == 0)
-			goto out_no_address;
-		args->nfs_server.addrlen = data->host_addrlen;
-		if (copy_from_user(sap, data->host_addr, data->host_addrlen))
-			return -EFAULT;
-		if (!nfs_verify_server_address(sap))
-			goto out_no_address;
-		args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
-
-		if (data->auth_flavourlen) {
-			rpc_authflavor_t pseudoflavor;
-			if (data->auth_flavourlen > 1)
-				goto out_inval_auth;
-			if (copy_from_user(&pseudoflavor,
-					   data->auth_flavours,
-					   sizeof(pseudoflavor)))
-				return -EFAULT;
-			args->selected_flavor = pseudoflavor;
-		} else
-			args->selected_flavor = RPC_AUTH_UNIX;
-
-		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
-		if (IS_ERR(c))
-			return PTR_ERR(c);
-		args->nfs_server.hostname = c;
-
-		c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
-		if (IS_ERR(c))
-			return PTR_ERR(c);
-		args->nfs_server.export_path = c;
-		dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
-
-		c = strndup_user(data->client_addr.data, 16);
-		if (IS_ERR(c))
-			return PTR_ERR(c);
-		args->client_address = c;
-
-		/*
-		 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
-		 * can deal with.
-		 */
-
-		args->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
-		args->rsize	= data->rsize;
-		args->wsize	= data->wsize;
-		args->timeo	= data->timeo;
-		args->retrans	= data->retrans;
-		args->acregmin	= data->acregmin;
-		args->acregmax	= data->acregmax;
-		args->acdirmin	= data->acdirmin;
-		args->acdirmax	= data->acdirmax;
-		args->nfs_server.protocol = data->proto;
-		nfs_validate_transport_protocol(args);
-		if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
-			goto out_invalid_transport_udp;
-
-		break;
-	default:
-		return NFS_TEXT_DATA;
-	}
-
-	return 0;
-
-out_no_data:
-	dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
-	return -EINVAL;
-
-out_inval_auth:
-	dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
-		 data->auth_flavourlen);
-	return -EINVAL;
-
-out_no_address:
-	dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
-	return -EINVAL;
-
-out_invalid_transport_udp:
-	dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
-	return -EINVAL;
-}
-
 /*
  * NFS v4 module parameters need to stay in the
  * NFS client for backwards compatibility
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 348f7c158084..ca0e3793cb50 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1540,6 +1540,7 @@ struct nfs_subversion;
 struct nfs_mount_info;
 struct nfs_client_initdata;
 struct nfs_pageio_descriptor;
+struct nfs_mount_context;
 
 /*
  * RPC procedure vector for NFSv2/NFSv3 demuxing
@@ -1553,10 +1554,10 @@ struct nfs_rpc_ops {
 
 	int	(*getroot) (struct nfs_server *, struct nfs_fh *,
 			    struct nfs_fsinfo *);
+	struct dentry *(*mount)(struct nfs_mount_context *);
 	struct vfsmount *(*submount) (struct nfs_server *, struct dentry *,
 				      struct nfs_fh *, struct nfs_fattr *);
-	struct dentry *(*try_mount) (int, const char *, struct nfs_mount_info *,
-				     struct nfs_subversion *);
+	struct dentry *(*try_mount) (struct nfs_mount_context *);
 	int	(*getattr) (struct nfs_server *, struct nfs_fh *,
 			    struct nfs_fattr *, struct nfs4_label *);
 	int	(*setattr) (struct dentry *, struct nfs_fattr *,
@@ -1617,7 +1618,7 @@ struct nfs_rpc_ops {
 	struct nfs_client *(*init_client) (struct nfs_client *,
 				const struct nfs_client_initdata *);
 	void	(*free_client) (struct nfs_client *);
-	struct nfs_server *(*create_server)(struct nfs_mount_info *, struct nfs_subversion *);
+	struct nfs_server *(*create_server)(struct nfs_mount_context *);
 	struct nfs_server *(*clone_server)(struct nfs_server *, struct nfs_fh *,
 					   struct nfs_fattr *, rpc_authflavor_t);
 };

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