Merge branch 'topic/core-cleanup' into for-linus
[safe/jmp/linux-2.6] / fs / nfs / super.c
index 719464a..b4148fc 100644 (file)
@@ -5,7 +5,7 @@
  *
  *  nfs superblock handling functions
  *
- *  Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some
+ *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  *
  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
@@ -33,6 +33,8 @@
 #include <linux/sunrpc/clnt.h>
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/metrics.h>
+#include <linux/sunrpc/xprtsock.h>
+#include <linux/sunrpc/xprtrdma.h>
 #include <linux/nfs_fs.h>
 #include <linux/nfs_mount.h>
 #include <linux/nfs4_mount.h>
 #include <linux/smp_lock.h>
 #include <linux/seq_file.h>
 #include <linux/mount.h>
+#include <linux/mnt_namespace.h>
+#include <linux/namei.h>
 #include <linux/nfs_idmap.h>
 #include <linux/vfs.h>
 #include <linux/inet.h>
+#include <linux/in6.h>
+#include <linux/slab.h>
+#include <net/ipv6.h>
+#include <linux/netdevice.h>
 #include <linux/nfs_xdr.h>
 #include <linux/magic.h>
+#include <linux/parser.h>
 
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include "delegation.h"
 #include "iostat.h"
 #include "internal.h"
+#include "fscache.h"
 
 #define NFSDBG_FACILITY                NFSDBG_VFS
 
-static void nfs_umount_begin(struct vfsmount *, int);
+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_v2, Opt_v3, Opt_v4,
+       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,
+
+       /* 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_nfsvers,
+       Opt_minorversion,
+
+       /* Mount options that take string arguments */
+       Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
+       Opt_addr, Opt_mountaddr, Opt_clientaddr,
+       Opt_lookupcache,
+       Opt_fscache_uniq,
+
+       /* 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_v2, "v2" },
+       { Opt_v3, "v3" },
+       { Opt_v4, "v4" },
+       { 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_fscache_uniq, "fsc=%s" },
+       { Opt_nofscache, "nofsc" },
+
+       { 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_nfsvers, "nfsvers=%s" },
+       { Opt_nfsvers, "vers=%s" },
+       { Opt_minorversion, "minorversion=%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_err, NULL }
+};
+
+enum {
+       Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
+
+       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_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 }
+};
+
+
+static void nfs_umount_begin(struct super_block *);
 static int  nfs_statfs(struct dentry *, struct kstatfs *);
 static int  nfs_show_options(struct seq_file *, struct vfsmount *);
 static int  nfs_show_stats(struct seq_file *, struct vfsmount *);
 static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *);
 static int nfs_xdev_get_sb(struct file_system_type *fs_type,
                int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static void nfs_put_super(struct super_block *);
 static void nfs_kill_super(struct super_block *);
+static int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
 
 static struct file_system_type nfs_fs_type = {
        .owner          = THIS_MODULE,
@@ -86,20 +268,30 @@ static const struct super_operations nfs_sops = {
        .alloc_inode    = nfs_alloc_inode,
        .destroy_inode  = nfs_destroy_inode,
        .write_inode    = nfs_write_inode,
+       .put_super      = nfs_put_super,
        .statfs         = nfs_statfs,
        .clear_inode    = nfs_clear_inode,
        .umount_begin   = nfs_umount_begin,
        .show_options   = nfs_show_options,
        .show_stats     = nfs_show_stats,
+       .remount_fs     = nfs_remount,
 };
 
 #ifdef CONFIG_NFS_V4
+static int nfs4_validate_text_mount_data(void *options,
+       struct nfs_parsed_mount_data *args, const char *dev_name);
+static int nfs4_try_mount(int flags, const char *dev_name,
+       struct nfs_parsed_mount_data *data, struct vfsmount *mnt);
 static int nfs4_get_sb(struct file_system_type *fs_type,
        int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static int nfs4_remote_get_sb(struct file_system_type *fs_type,
+       int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static int nfs4_xdev_get_sb(struct file_system_type *fs_type,
        int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static int nfs4_referral_get_sb(struct file_system_type *fs_type,
        int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
+static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
+       int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt);
 static void nfs4_kill_super(struct super_block *sb);
 
 static struct file_system_type nfs4_fs_type = {
@@ -110,6 +302,14 @@ static struct file_system_type nfs4_fs_type = {
        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 };
 
+static struct file_system_type nfs4_remote_fs_type = {
+       .owner          = THIS_MODULE,
+       .name           = "nfs4",
+       .get_sb         = nfs4_remote_get_sb,
+       .kill_sb        = nfs4_kill_super,
+       .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
 struct file_system_type nfs4_xdev_fs_type = {
        .owner          = THIS_MODULE,
        .name           = "nfs4",
@@ -118,6 +318,14 @@ struct file_system_type nfs4_xdev_fs_type = {
        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 };
 
+static struct file_system_type nfs4_remote_referral_fs_type = {
+       .owner          = THIS_MODULE,
+       .name           = "nfs4",
+       .get_sb         = nfs4_remote_referral_get_sb,
+       .kill_sb        = nfs4_kill_super,
+       .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
 struct file_system_type nfs4_referral_fs_type = {
        .owner          = THIS_MODULE,
        .name           = "nfs4",
@@ -130,15 +338,20 @@ static const struct super_operations nfs4_sops = {
        .alloc_inode    = nfs_alloc_inode,
        .destroy_inode  = nfs_destroy_inode,
        .write_inode    = nfs_write_inode,
+       .put_super      = nfs_put_super,
        .statfs         = nfs_statfs,
        .clear_inode    = nfs4_clear_inode,
        .umount_begin   = nfs_umount_begin,
        .show_options   = nfs_show_options,
        .show_stats     = nfs_show_stats,
+       .remount_fs     = nfs_remount,
 };
 #endif
 
-static struct shrinker *acl_shrinker;
+static struct shrinker acl_shrinker = {
+       .shrink         = nfs_access_cache_shrinker,
+       .seeks          = DEFAULT_SEEKS,
+};
 
 /*
  * Register the NFS filesystems
@@ -159,7 +372,7 @@ int __init register_nfs_fs(void)
        if (ret < 0)
                goto error_2;
 #endif
-       acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker);
+       register_shrinker(&acl_shrinker);
        return 0;
 
 #ifdef CONFIG_NFS_V4
@@ -177,15 +390,30 @@ error_0:
  */
 void __exit unregister_nfs_fs(void)
 {
-       if (acl_shrinker != NULL)
-               remove_shrinker(acl_shrinker);
+       unregister_shrinker(&acl_shrinker);
 #ifdef CONFIG_NFS_V4
        unregister_filesystem(&nfs4_fs_type);
-       nfs_unregister_sysctl();
 #endif
+       nfs_unregister_sysctl();
        unregister_filesystem(&nfs_fs_type);
 }
 
+void nfs_sb_active(struct super_block *sb)
+{
+       struct nfs_server *server = NFS_SB(sb);
+
+       if (atomic_inc_return(&server->active) == 1)
+               atomic_inc(&sb->s_active);
+}
+
+void nfs_sb_deactive(struct super_block *sb)
+{
+       struct nfs_server *server = NFS_SB(sb);
+
+       if (atomic_dec_and_test(&server->active))
+               deactivate_super(sb);
+}
+
 /*
  * Deliver file system statistics to userspace
  */
@@ -201,8 +429,6 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
        };
        int error;
 
-       lock_kernel();
-
        error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
        if (error < 0)
                goto out_err;
@@ -234,12 +460,10 @@ static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 
        buf->f_namelen = server->namelen;
 
-       unlock_kernel();
        return 0;
 
  out_err:
-       dprintk("%s: statfs error = %d\n", __FUNCTION__, -error);
-       unlock_kernel();
+       dprintk("%s: statfs error = %d\n", __func__, -error);
        return error;
 }
 
@@ -263,21 +487,90 @@ static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
                { RPC_AUTH_GSS_SPKM, "spkm" },
                { RPC_AUTH_GSS_SPKMI, "spkmi" },
                { RPC_AUTH_GSS_SPKMP, "spkmp" },
-               { -1, "unknown" }
+               { UINT_MAX, "unknown" }
        };
        int i;
 
-       for (i=0; sec_flavours[i].flavour != -1; i++) {
+       for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
                if (sec_flavours[i].flavour == flavour)
                        break;
        }
        return sec_flavours[i].str;
 }
 
+static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
+                                 int showdefaults)
+{
+       struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
+
+       seq_printf(m, ",mountproto=");
+       switch (sap->sa_family) {
+       case AF_INET:
+               switch (nfss->mountd_protocol) {
+               case IPPROTO_UDP:
+                       seq_printf(m, RPCBIND_NETID_UDP);
+                       break;
+               case IPPROTO_TCP:
+                       seq_printf(m, RPCBIND_NETID_TCP);
+                       break;
+               default:
+                       if (showdefaults)
+                               seq_printf(m, "auto");
+               }
+               break;
+       case AF_INET6:
+               switch (nfss->mountd_protocol) {
+               case IPPROTO_UDP:
+                       seq_printf(m, RPCBIND_NETID_UDP6);
+                       break;
+               case IPPROTO_TCP:
+                       seq_printf(m, RPCBIND_NETID_TCP6);
+                       break;
+               default:
+                       if (showdefaults)
+                               seq_printf(m, "auto");
+               }
+               break;
+       default:
+               if (showdefaults)
+                       seq_printf(m, "auto");
+       }
+}
+
+static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
+                                   int showdefaults)
+{
+       struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
+
+       switch (sap->sa_family) {
+       case AF_INET: {
+               struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+               seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
+               break;
+       }
+       case AF_INET6: {
+               struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
+               seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
+               break;
+       }
+       default:
+               if (showdefaults)
+                       seq_printf(m, ",mountaddr=unspecified");
+       }
+
+       if (nfss->mountd_version || showdefaults)
+               seq_printf(m, ",mountvers=%u", nfss->mountd_version);
+       if (nfss->mountd_port || showdefaults)
+               seq_printf(m, ",mountport=%u", nfss->mountd_port);
+
+       nfs_show_mountd_netid(m, nfss, showdefaults);
+}
+
 /*
  * Describe the mount options in force on this server representation
  */
-static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults)
+static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
+                                  int showdefaults)
 {
        static const struct proc_nfs_info {
                int flag;
@@ -285,50 +578,62 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
                const char *nostr;
        } nfs_info[] = {
                { NFS_MOUNT_SOFT, ",soft", ",hard" },
-               { NFS_MOUNT_INTR, ",intr", "" },
+               { NFS_MOUNT_POSIX, ",posix", "" },
                { NFS_MOUNT_NOCTO, ",nocto", "" },
                { NFS_MOUNT_NOAC, ",noac", "" },
                { NFS_MOUNT_NONLM, ",nolock", "" },
                { NFS_MOUNT_NOACL, ",noacl", "" },
+               { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
+               { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
+               { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
                { 0, NULL, NULL }
        };
        const struct proc_nfs_info *nfs_infop;
        struct nfs_client *clp = nfss->nfs_client;
-       char buf[12];
-       const char *proto;
-
-       seq_printf(m, ",vers=%d", clp->rpc_ops->version);
-       seq_printf(m, ",rsize=%d", nfss->rsize);
-       seq_printf(m, ",wsize=%d", nfss->wsize);
-       if (nfss->acregmin != 3*HZ || showdefaults)
-               seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ);
-       if (nfss->acregmax != 60*HZ || showdefaults)
-               seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ);
-       if (nfss->acdirmin != 30*HZ || showdefaults)
-               seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ);
-       if (nfss->acdirmax != 60*HZ || showdefaults)
-               seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ);
+       u32 version = clp->rpc_ops->version;
+
+       seq_printf(m, ",vers=%u", version);
+       seq_printf(m, ",rsize=%u", nfss->rsize);
+       seq_printf(m, ",wsize=%u", nfss->wsize);
+       if (nfss->bsize != 0)
+               seq_printf(m, ",bsize=%u", nfss->bsize);
+       seq_printf(m, ",namlen=%u", nfss->namelen);
+       if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
+               seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
+       if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
+               seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
+       if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
+               seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
+       if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
+               seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
        for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
                if (nfss->flags & nfs_infop->flag)
                        seq_puts(m, nfs_infop->str);
                else
                        seq_puts(m, nfs_infop->nostr);
        }
-       switch (nfss->client->cl_xprt->prot) {
-               case IPPROTO_TCP:
-                       proto = "tcp";
-                       break;
-               case IPPROTO_UDP:
-                       proto = "udp";
-                       break;
-               default:
-                       snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot);
-                       proto = buf;
-       }
-       seq_printf(m, ",proto=%s", proto);
-       seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ);
-       seq_printf(m, ",retrans=%u", clp->retrans_count);
+       seq_printf(m, ",proto=%s",
+                  rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
+       if (version == 4) {
+               if (nfss->port != NFS_PORT)
+                       seq_printf(m, ",port=%u", nfss->port);
+       } else
+               if (nfss->port)
+                       seq_printf(m, ",port=%u", nfss->port);
+
+       seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
+       seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
        seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
+
+       if (version != 4)
+               nfs_show_mountd_options(m, nfss, showdefaults);
+
+#ifdef CONFIG_NFS_V4
+       if (clp->rpc_ops->version == 4)
+               seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
+#endif
+       if (nfss->options & NFS_OPTION_FSCACHE)
+               seq_printf(m, ",fsc");
 }
 
 /*
@@ -340,8 +645,9 @@ static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt)
 
        nfs_show_mount_options(m, nfss, 0);
 
-       seq_puts(m, ",addr=");
-       seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\");
+       seq_printf(m, ",addr=%s",
+                       rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
+                                                       RPC_DISPLAY_ADDR));
 
        return 0;
 }
@@ -372,13 +678,13 @@ static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
 
        seq_printf(m, "\n\tcaps:\t");
        seq_printf(m, "caps=0x%x", nfss->caps);
-       seq_printf(m, ",wtmult=%d", nfss->wtmult);
-       seq_printf(m, ",dtsize=%d", nfss->dtsize);
-       seq_printf(m, ",bsize=%d", nfss->bsize);
-       seq_printf(m, ",namelen=%d", nfss->namelen);
+       seq_printf(m, ",wtmult=%u", nfss->wtmult);
+       seq_printf(m, ",dtsize=%u", nfss->dtsize);
+       seq_printf(m, ",bsize=%u", nfss->bsize);
+       seq_printf(m, ",namlen=%u", nfss->namelen);
 
 #ifdef CONFIG_NFS_V4
-       if (nfss->nfs_client->cl_nfsversion == 4) {
+       if (nfss->nfs_client->rpc_ops->version == 4) {
                seq_printf(m, "\n\tnfsv4:\t");
                seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
                seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
@@ -389,9 +695,9 @@ static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
        /*
         * Display security flavor in effect for this mount
         */
-       seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor);
+       seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
        if (auth->au_flavor)
-               seq_printf(m, ",pseudoflavor=%d", auth->au_flavor);
+               seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 
        /*
         * Display superblock I/O counters
@@ -406,110 +712,1267 @@ static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt)
                        totals.events[i] += stats->events[i];
                for (i = 0; i < __NFSIOS_BYTESMAX; i++)
                        totals.bytes[i] += stats->bytes[i];
+#ifdef CONFIG_NFS_FSCACHE
+               for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
+                       totals.fscache[i] += stats->fscache[i];
+#endif
+
+               preempt_enable();
+       }
+
+       seq_printf(m, "\n\tevents:\t");
+       for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
+               seq_printf(m, "%lu ", totals.events[i]);
+       seq_printf(m, "\n\tbytes:\t");
+       for (i = 0; i < __NFSIOS_BYTESMAX; i++)
+               seq_printf(m, "%Lu ", totals.bytes[i]);
+#ifdef CONFIG_NFS_FSCACHE
+       if (nfss->options & NFS_OPTION_FSCACHE) {
+               seq_printf(m, "\n\tfsc:\t");
+               for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
+                       seq_printf(m, "%Lu ", totals.bytes[i]);
+       }
+#endif
+       seq_printf(m, "\n");
+
+       rpc_print_iostats(m, nfss->client);
+
+       return 0;
+}
+
+/*
+ * Begin unmount by attempting to remove all automounted mountpoints we added
+ * in response to xdev traversals and referrals
+ */
+static void nfs_umount_begin(struct super_block *sb)
+{
+       struct nfs_server *server;
+       struct rpc_clnt *rpc;
+
+       server = NFS_SB(sb);
+       /* -EIO all pending I/O */
+       rpc = server->client_acl;
+       if (!IS_ERR(rpc))
+               rpc_killall_tasks(rpc);
+       rpc = server->client;
+       if (!IS_ERR(rpc))
+               rpc_killall_tasks(rpc);
+}
+
+static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(unsigned int version)
+{
+       struct nfs_parsed_mount_data *data;
+
+       data = kzalloc(sizeof(*data), GFP_KERNEL);
+       if (data) {
+               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->auth_flavors[0]   = RPC_AUTH_UNIX;
+               data->auth_flavor_len   = 1;
+               data->version           = version;
+               data->minorversion      = 0;
+       }
+       return 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;
+       }
+}
+
+/*
+ * 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];
+
+       dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
+
+       switch (match_token(value, nfs_secflavor_tokens, args)) {
+       case Opt_sec_none:
+               mnt->auth_flavors[0] = RPC_AUTH_NULL;
+               break;
+       case Opt_sec_sys:
+               mnt->auth_flavors[0] = RPC_AUTH_UNIX;
+               break;
+       case Opt_sec_krb5:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
+               break;
+       case Opt_sec_krb5i:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
+               break;
+       case Opt_sec_krb5p:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
+               break;
+       case Opt_sec_lkey:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
+               break;
+       case Opt_sec_lkeyi:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
+               break;
+       case Opt_sec_lkeyp:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
+               break;
+       case Opt_sec_spkm:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
+               break;
+       case Opt_sec_spkmi:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
+               break;
+       case Opt_sec_spkmp:
+               mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
+               break;
+       default:
+               return 0;
+       }
+
+       mnt->auth_flavor_len = 1;
+       return 1;
+}
+
+/*
+ * 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;
+                       break;
+               case Opt_nolock:
+                       mnt->flags |= NFS_MOUNT_NONLM;
+                       break;
+               case Opt_v2:
+                       mnt->flags &= ~NFS_MOUNT_VER3;
+                       mnt->version = 2;
+                       break;
+               case Opt_v3:
+                       mnt->flags |= NFS_MOUNT_VER3;
+                       mnt->version = 3;
+                       break;
+#ifdef CONFIG_NFS_V4
+               case Opt_v4:
+                       mnt->flags &= ~NFS_MOUNT_VER3;
+                       mnt->version = 4;
+                       break;
+#endif
+               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_fscache_uniq:
+                       string = match_strdup(args);
+                       if (!string)
+                               goto out_nomem;
+                       kfree(mnt->fscache_uniq);
+                       mnt->fscache_uniq = string;
+                       mnt->options |= NFS_OPTION_FSCACHE;
+                       break;
+
+               /*
+                * options that take numeric values
+                */
+               case Opt_port:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0 || option > USHORT_MAX)
+                               goto out_invalid_value;
+                       mnt->nfs_server.port = option;
+                       break;
+               case Opt_rsize:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->rsize = option;
+                       break;
+               case Opt_wsize:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->wsize = option;
+                       break;
+               case Opt_bsize:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->bsize = option;
+                       break;
+               case Opt_timeo:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0 || option == 0)
+                               goto out_invalid_value;
+                       mnt->timeo = option;
+                       break;
+               case Opt_retrans:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0 || option == 0)
+                               goto out_invalid_value;
+                       mnt->retrans = option;
+                       break;
+               case Opt_acregmin:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->acregmin = option;
+                       break;
+               case Opt_acregmax:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->acregmax = option;
+                       break;
+               case Opt_acdirmin:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->acdirmin = option;
+                       break;
+               case Opt_acdirmax:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->acdirmax = option;
+                       break;
+               case Opt_actimeo:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->acregmin = mnt->acregmax =
+                       mnt->acdirmin = mnt->acdirmax = option;
+                       break;
+               case Opt_namelen:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       mnt->namlen = option;
+                       break;
+               case Opt_mountport:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0 || option > USHORT_MAX)
+                               goto out_invalid_value;
+                       mnt->mount_server.port = option;
+                       break;
+               case Opt_mountvers:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0 ||
+                           option < NFS_MNT_VERSION ||
+                           option > NFS_MNT3_VERSION)
+                               goto out_invalid_value;
+                       mnt->mount_server.version = option;
+                       break;
+               case Opt_nfsvers:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               goto out_invalid_value;
+                       switch (option) {
+                       case NFS2_VERSION:
+                               mnt->flags &= ~NFS_MOUNT_VER3;
+                               mnt->version = 2;
+                               break;
+                       case NFS3_VERSION:
+                               mnt->flags |= NFS_MOUNT_VER3;
+                               mnt->version = 3;
+                               break;
+#ifdef CONFIG_NFS_V4
+                       case NFS4_VERSION:
+                               mnt->flags &= ~NFS_MOUNT_VER3;
+                               mnt->version = 4;
+                               break;
+#endif
+                       default:
+                               goto out_invalid_value;
+                       }
+                       break;
+               case Opt_minorversion:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       rc = strict_strtoul(string, 10, &option);
+                       kfree(string);
+                       if (rc != 0)
+                               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_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;
+                               kfree(string);
+                               break;
+                       case Opt_xprt_tcp6:
+                               protofamily = AF_INET6;
+                       case Opt_xprt_tcp:
+                               mnt->flags |= NFS_MOUNT_TCP;
+                               mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+                               kfree(string);
+                               break;
+                       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);
+                               kfree(string);
+                               break;
+                       default:
+                               dfprintk(MOUNT, "NFS:   unrecognized "
+                                               "transport protocol\n");
+                               kfree(string);
+                               return 0;
+                       }
+                       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(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:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       kfree(mnt->client_address);
+                       mnt->client_address = string;
+                       break;
+               case Opt_mounthost:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       kfree(mnt->mount_server.hostname);
+                       mnt->mount_server.hostname = string;
+                       break;
+               case Opt_mountaddr:
+                       string = match_strdup(args);
+                       if (string == NULL)
+                               goto out_nomem;
+                       mnt->mount_server.addrlen =
+                               rpc_pton(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;
+
+               /*
+                * 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;
+
+       /*
+        * verify that any proto=/mountproto= options match the address
+        * familiies 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_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;
+}
+
+/*
+ * Match the requested auth flavors with the list returned by
+ * the server.  Returns zero and sets the mount's authentication
+ * flavor on success; returns -EACCES if server does not support
+ * the requested flavor.
+ */
+static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
+                            struct nfs_mount_request *request)
+{
+       unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
+
+       /*
+        * Certain releases of Linux's mountd return an empty
+        * flavor list.  To prevent behavioral regression with
+        * these servers (ie. rejecting mounts that used to
+        * succeed), revert to pre-2.6.32 behavior (no checking)
+        * if the returned flavor list is empty.
+        */
+       if (server_authlist_len == 0)
+               return 0;
+
+       /*
+        * We avoid sophisticated negotiating here, as there are
+        * plenty of cases where we can get it wrong, providing
+        * either too little or too much security.
+        *
+        * RFC 2623, section 2.7 suggests we SHOULD prefer the
+        * flavor listed first.  However, some servers list
+        * AUTH_NULL first.  Our caller plants AUTH_SYS, the
+        * preferred default, in args->auth_flavors[0] if user
+        * didn't specify sec= mount option.
+        */
+       for (i = 0; i < args->auth_flavor_len; i++)
+               for (j = 0; j < server_authlist_len; j++)
+                       if (args->auth_flavors[i] == request->auth_flavs[j]) {
+                               dfprintk(MOUNT, "NFS: using auth flavor %d\n",
+                                       request->auth_flavs[j]);
+                               args->auth_flavors[0] = request->auth_flavs[j];
+                               return 0;
+                       }
+
+       dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
+       nfs_umount(request);
+       return -EACCES;
+}
+
+/*
+ * Use the remote server's MOUNT service to request the NFS file handle
+ * corresponding to the provided path.
+ */
+static int nfs_try_mount(struct nfs_parsed_mount_data *args,
+                        struct nfs_fh *root_fh)
+{
+       rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
+       unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
+       struct nfs_mount_request request = {
+               .sap            = (struct sockaddr *)
+                                               &args->mount_server.address,
+               .dirpath        = args->nfs_server.export_path,
+               .protocol       = args->mount_server.protocol,
+               .fh             = root_fh,
+               .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
+               .auth_flav_len  = &server_authlist_len,
+               .auth_flavs     = server_authlist,
+       };
+       int status;
+
+       if (args->mount_server.version == 0) {
+               switch (args->version) {
+                       default:
+                               args->mount_server.version = NFS_MNT3_VERSION;
+                               break;
+                       case 2:
+                               args->mount_server.version = NFS_MNT_VERSION;
+               }
+       }
+       request.version = args->mount_server.version;
+
+       if (args->mount_server.hostname)
+               request.hostname = args->mount_server.hostname;
+       else
+               request.hostname = args->nfs_server.hostname;
+
+       /*
+        * Construct the mount server's address.
+        */
+       if (args->mount_server.address.ss_family == AF_UNSPEC) {
+               memcpy(request.sap, &args->nfs_server.address,
+                      args->nfs_server.addrlen);
+               args->mount_server.addrlen = args->nfs_server.addrlen;
+       }
+       request.salen = args->mount_server.addrlen;
+       nfs_set_port(request.sap, &args->mount_server.port, 0);
+
+       /*
+        * Now ask the mount server to map our export path
+        * to a file handle.
+        */
+       status = nfs_mount(&request);
+       if (status != 0) {
+               dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
+                               request.hostname, status);
+               return status;
+       }
+
+       /*
+        * MNTv1 (NFSv2) does not support auth flavor negotiation.
+        */
+       if (args->mount_server.version != NFS_MNT3_VERSION)
+               return 0;
+       return nfs_walk_authlist(args, &request);
+}
+
+static int nfs_parse_simple_hostname(const char *dev_name,
+                                    char **hostname, size_t maxnamlen,
+                                    char **export_path, size_t maxpathlen)
+{
+       size_t len;
+       char *colon, *comma;
+
+       colon = strchr(dev_name, ':');
+       if (colon == NULL)
+               goto out_bad_devname;
+
+       len = colon - dev_name;
+       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)
+               goto out_nomem;
+
+       /* kill possible hostname list: not supported */
+       comma = strchr(*hostname, ',');
+       if (comma != NULL) {
+               if (comma == *hostname)
+                       goto out_bad_devname;
+               *comma = '\0';
+       }
+
+       colon++;
+       len = strlen(colon);
+       if (len > maxpathlen)
+               goto out_path;
+       *export_path = kstrndup(colon, 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;
+}
+
+/*
+ * Hostname has square brackets around it because it contains one or
+ * more colons.  We look for the first closing square bracket, and a
+ * colon must follow it.
+ */
+static int nfs_parse_protected_hostname(const char *dev_name,
+                                       char **hostname, size_t maxnamlen,
+                                       char **export_path, size_t maxpathlen)
+{
+       size_t len;
+       char *start, *end;
+
+       start = (char *)(dev_name + 1);
+
+       end = strchr(start, ']');
+       if (end == NULL)
+               goto out_bad_devname;
+       if (*(end + 1) != ':')
+               goto out_bad_devname;
+
+       len = end - start;
+       if (len > maxnamlen)
+               goto out_hostname;
+
+       /* N.B. caller will free nfs_server.hostname in all cases */
+       *hostname = kstrndup(start, len, GFP_KERNEL);
+       if (*hostname == NULL)
+               goto out_nomem;
+
+       end += 2;
+       len = strlen(end);
+       if (len > maxpathlen)
+               goto out_path;
+       *export_path = kstrndup(end, len, GFP_KERNEL);
+       if (!*export_path)
+               goto out_nomem;
+
+       return 0;
 
-               preempt_enable();
-       }
+out_bad_devname:
+       dfprintk(MOUNT, "NFS: device name not in host:path format\n");
+       return -EINVAL;
 
-       seq_printf(m, "\n\tevents:\t");
-       for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
-               seq_printf(m, "%lu ", totals.events[i]);
-       seq_printf(m, "\n\tbytes:\t");
-       for (i = 0; i < __NFSIOS_BYTESMAX; i++)
-               seq_printf(m, "%Lu ", totals.bytes[i]);
-       seq_printf(m, "\n");
+out_nomem:
+       dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
+       return -ENOMEM;
 
-       rpc_print_iostats(m, nfss->client);
+out_hostname:
+       dfprintk(MOUNT, "NFS: server hostname too long\n");
+       return -ENAMETOOLONG;
 
-       return 0;
+out_path:
+       dfprintk(MOUNT, "NFS: export pathname too long\n");
+       return -ENAMETOOLONG;
 }
 
 /*
- * Begin unmount by attempting to remove all automounted mountpoints we added
- * in response to xdev traversals and referrals
+ * 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 void nfs_umount_begin(struct vfsmount *vfsmnt, int flags)
+static int nfs_parse_devname(const char *dev_name,
+                            char **hostname, size_t maxnamlen,
+                            char **export_path, size_t maxpathlen)
 {
-       shrink_submounts(vfsmnt, &nfs_automount_list);
+       if (*dev_name == '[')
+               return nfs_parse_protected_hostname(dev_name,
+                                                   hostname, maxnamlen,
+                                                   export_path, maxpathlen);
+
+       return nfs_parse_simple_hostname(dev_name,
+                                        hostname, maxnamlen,
+                                        export_path, maxpathlen);
 }
 
 /*
  * 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 nfs_validate_mount_data(struct nfs_mount_data *data,
-                                  struct nfs_fh *mntfh)
+static int nfs_validate_mount_data(void *options,
+                                  struct nfs_parsed_mount_data *args,
+                                  struct nfs_fh *mntfh,
+                                  const char *dev_name)
 {
-       if (data == NULL) {
-               dprintk("%s: missing data argument\n", __FUNCTION__);
-               return -EINVAL;
-       }
+       struct nfs_mount_data *data = (struct nfs_mount_data *)options;
+       struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
 
-       if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) {
-               dprintk("%s: bad mount version\n", __FUNCTION__);
-               return -EINVAL;
-       }
+       if (data == NULL)
+               goto out_no_data;
 
        switch (data->version) {
-               case 1:
-                       data->namlen = 0;
-               case 2:
-                       data->bsize  = 0;
-               case 3:
-                       if (data->flags & NFS_MOUNT_VER3) {
-                               dprintk("%s: mount structure version %d does not support NFSv3\n",
-                                               __FUNCTION__,
-                                               data->version);
-                               return -EINVAL;
-                       }
-                       data->root.size = NFS2_FHSIZE;
-                       memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
-               case 4:
-                       if (data->flags & NFS_MOUNT_SECFLAVOUR) {
-                               dprintk("%s: mount structure version %d does not support strong security\n",
-                                               __FUNCTION__,
-                                               data->version);
-                               return -EINVAL;
-                       }
-               case 5:
-                       memset(data->context, 0, sizeof(data->context));
+       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);
+       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->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;
+
+               memcpy(sap, &data->addr, sizeof(data->addr));
+               args->nfs_server.addrlen = sizeof(data->addr);
+               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->auth_flavors[0] = data->pseudoflavor;
+               if (!args->nfs_server.hostname)
+                       goto out_nomem;
+
+               /*
+                * 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: {
+               int status;
+
+               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)
+#ifdef CONFIG_NFS_V4
+                       return nfs4_validate_text_mount_data(options,
+                                                            args, dev_name);
+#else
+                       goto out_v4_not_compiled;
+#endif
+
+               nfs_set_port(sap, &args->nfs_server.port, 0);
+
+               nfs_set_mount_transport_protocol(args);
+
+               status = nfs_parse_devname(dev_name,
+                                          &args->nfs_server.hostname,
+                                          PAGE_SIZE,
+                                          &args->nfs_server.export_path,
+                                          NFS_MAXPATHLEN);
+               if (!status)
+                       status = nfs_try_mount(args, mntfh);
+
+               kfree(args->nfs_server.export_path);
+               args->nfs_server.export_path = NULL;
+
+               if (status)
+                       return status;
+
+               break;
+               }
        }
 
-       /* Set the pseudoflavor */
-       if (!(data->flags & NFS_MOUNT_SECFLAVOUR))
-               data->pseudoflavor = RPC_AUTH_UNIX;
+#ifndef CONFIG_NFS_V3
+       if (args->version == 3)
+               goto out_v3_not_compiled;
+#endif /* !CONFIG_NFS_V3 */
+
+       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;
 
 #ifndef CONFIG_NFS_V3
-       /* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */
-       if (data->flags & NFS_MOUNT_VER3) {
-               dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__);
-               return -EPROTONOSUPPORT;
-       }
-#endif /* CONFIG_NFS_V3 */
+out_v3_not_compiled:
+       dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
+       return -EPROTONOSUPPORT;
+#endif /* !CONFIG_NFS_V3 */
+
+#ifndef CONFIG_NFS_V4
+out_v4_not_compiled:
+       dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
+       return -EPROTONOSUPPORT;
+#endif /* !CONFIG_NFS_V4 */
+
+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;
+}
 
-       /* We now require that the mount process passes the remote address */
-       if (data->addr.sin_addr.s_addr == INADDR_ANY) {
-               dprintk("%s: mount program didn't pass remote address!\n",
-                       __FUNCTION__);
+static int
+nfs_compare_remount_data(struct nfs_server *nfss,
+                        struct nfs_parsed_mount_data *data)
+{
+       if (data->flags != nfss->flags ||
+           data->rsize != nfss->rsize ||
+           data->wsize != nfss->wsize ||
+           data->retrans != nfss->client->cl_timeout->to_retries ||
+           data->auth_flavors[0] != 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 ||
+           !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
+                         (struct sockaddr *)&nfss->nfs_client->cl_addr))
                return -EINVAL;
-       }
 
-       /* Prepare the root filehandle */
-       if (data->flags & NFS_MOUNT_VER3)
-               mntfh->size = data->root.size;
-       else
-               mntfh->size = NFS2_FHSIZE;
+       return 0;
+}
 
-       if (mntfh->size > sizeof(mntfh->data)) {
-               dprintk("%s: invalid root filehandle\n", __FUNCTION__);
-               return -EINVAL;
-       }
+static int
+nfs_remount(struct super_block *sb, int *flags, char *raw_data)
+{
+       int error;
+       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;
+
+       /*
+        * Userspace mount programs that send binary options generally send
+        * them populated with default values. We have no way to know which
+        * 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))))
+               return 0;
 
-       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);
+       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->auth_flavors[0] = 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;
+       memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
+               data->nfs_server.addrlen);
+
+       /* overwrite those values with any that were specified */
+       error = nfs_parse_mount_options((char *)options, data);
+       if (error < 0)
+               goto out;
 
-       return 0;
+       /* compare new mount options with old ones */
+       error = nfs_compare_remount_data(nfss, data);
+out:
+       kfree(data);
+       return error;
 }
 
 /*
@@ -532,13 +1995,16 @@ static inline void nfs_initialise_sb(struct super_block *sb)
        if (server->flags & NFS_MOUNT_NOAC)
                sb->s_flags |= MS_SYNCHRONOUS;
 
+       sb->s_bdi = &server->backing_dev_info;
+
        nfs_super_set_maxbytes(sb, server->maxfilesize);
 }
 
 /*
  * Finish setting up an NFS2/3 superblock
  */
-static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
+static void nfs_fill_super(struct super_block *sb,
+                          struct nfs_parsed_mount_data *data)
 {
        struct nfs_server *server = NFS_SB(sb);
 
@@ -547,7 +2013,7 @@ static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data)
        if (data->bsize)
                sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
 
-       if (server->flags & NFS_MOUNT_VER3) {
+       if (server->nfs_client->rpc_ops->version == 3) {
                /* The VFS shouldn't apply the umask to mode bits. We will do
                 * so ourselves when necessary.
                 */
@@ -571,7 +2037,7 @@ static void nfs_clone_super(struct super_block *sb,
        sb->s_blocksize = old_sb->s_blocksize;
        sb->s_maxbytes = old_sb->s_maxbytes;
 
-       if (server->flags & NFS_MOUNT_VER3) {
+       if (server->nfs_client->rpc_ops->version == 3) {
                /* The VFS shouldn't apply the umask to mode bits. We will do
                 * so ourselves when necessary.
                 */
@@ -583,11 +2049,49 @@ static void nfs_clone_super(struct super_block *sb,
        nfs_initialise_sb(sb);
 }
 
-static int nfs_set_super(struct super_block *s, void *_server)
+static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
+{
+       const struct nfs_server *a = s->s_fs_info;
+       const struct rpc_clnt *clnt_a = a->client;
+       const struct rpc_clnt *clnt_b = b->client;
+
+       if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
+               goto Ebusy;
+       if (a->nfs_client != b->nfs_client)
+               goto Ebusy;
+       if (a->flags != b->flags)
+               goto Ebusy;
+       if (a->wsize != b->wsize)
+               goto Ebusy;
+       if (a->rsize != b->rsize)
+               goto Ebusy;
+       if (a->acregmin != b->acregmin)
+               goto Ebusy;
+       if (a->acregmax != b->acregmax)
+               goto Ebusy;
+       if (a->acdirmin != b->acdirmin)
+               goto Ebusy;
+       if (a->acdirmax != b->acdirmax)
+               goto Ebusy;
+       if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
+               goto Ebusy;
+       return 1;
+Ebusy:
+       return 0;
+}
+
+struct nfs_sb_mountdata {
+       struct nfs_server *server;
+       int mntflags;
+};
+
+static int nfs_set_super(struct super_block *s, void *data)
 {
-       struct nfs_server *server = _server;
+       struct nfs_sb_mountdata *sb_mntdata = data;
+       struct nfs_server *server = sb_mntdata->server;
        int ret;
 
+       s->s_flags = sb_mntdata->mntflags;
        s->s_fs_info = server;
        ret = set_anon_super(s, server);
        if (ret == 0)
@@ -595,15 +2099,62 @@ static int nfs_set_super(struct super_block *s, void *_server)
        return ret;
 }
 
+static int nfs_compare_super_address(struct nfs_server *server1,
+                                    struct nfs_server *server2)
+{
+       struct sockaddr *sap1, *sap2;
+
+       sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
+       sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
+
+       if (sap1->sa_family != sap2->sa_family)
+               return 0;
+
+       switch (sap1->sa_family) {
+       case AF_INET: {
+               struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
+               struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
+               if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
+                       return 0;
+               if (sin1->sin_port != sin2->sin_port)
+                       return 0;
+               break;
+       }
+       case AF_INET6: {
+               struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
+               struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
+               if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
+                       return 0;
+               if (sin1->sin6_port != sin2->sin6_port)
+                       return 0;
+               break;
+       }
+       default:
+               return 0;
+       }
+
+       return 1;
+}
+
 static int nfs_compare_super(struct super_block *sb, void *data)
 {
-       struct nfs_server *server = data, *old = NFS_SB(sb);
+       struct nfs_sb_mountdata *sb_mntdata = data;
+       struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
+       int mntflags = sb_mntdata->mntflags;
 
-       if (old->nfs_client != server->nfs_client)
+       if (!nfs_compare_super_address(old, server))
+               return 0;
+       /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
+       if (old->flags & NFS_MOUNT_UNSHARED)
                return 0;
        if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
                return 0;
-       return 1;
+       return nfs_compare_mount_options(sb, server, mntflags);
+}
+
+static int nfs_bdi_register(struct nfs_server *server)
+{
+       return bdi_register_dev(&server->backing_dev_info, server->s_dev);
 }
 
 static int nfs_get_sb(struct file_system_type *fs_type,
@@ -611,25 +2162,49 @@ static int nfs_get_sb(struct file_system_type *fs_type,
 {
        struct nfs_server *server = NULL;
        struct super_block *s;
-       struct nfs_fh mntfh;
-       struct nfs_mount_data *data = raw_data;
+       struct nfs_parsed_mount_data *data;
+       struct nfs_fh *mntfh;
        struct dentry *mntroot;
-       int error;
+       int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
+       struct nfs_sb_mountdata sb_mntdata = {
+               .mntflags = flags,
+       };
+       int error = -ENOMEM;
+
+       data = nfs_alloc_parsed_mount_data(3);
+       mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+       if (data == NULL || mntfh == NULL)
+               goto out_free_fh;
+
+       security_init_mnt_opts(&data->lsm_opts);
 
        /* Validate the mount data */
-       error = nfs_validate_mount_data(data, &mntfh);
+       error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
        if (error < 0)
-               return error;
+               goto out;
+
+#ifdef CONFIG_NFS_V4
+       if (data->version == 4) {
+               error = nfs4_try_mount(flags, dev_name, data, mnt);
+               kfree(data->client_address);
+               kfree(data->nfs_server.export_path);
+               goto out;
+       }
+#endif /* CONFIG_NFS_V4 */
 
        /* Get a volume representation */
-       server = nfs_create_server(data, &mntfh);
+       server = nfs_create_server(data, mntfh);
        if (IS_ERR(server)) {
                error = PTR_ERR(server);
-               goto out_err_noserver;
+               goto out;
        }
+       sb_mntdata.server = server;
+
+       if (server->flags & NFS_MOUNT_UNSHARED)
+               compare_super = NULL;
 
        /* Get a superblock - note that we may end up sharing one that already exists */
-       s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
+       s = sget(fs_type, compare_super, nfs_set_super, &sb_mntdata);
        if (IS_ERR(s)) {
                error = PTR_ERR(s);
                goto out_err_nosb;
@@ -638,34 +2213,67 @@ static int nfs_get_sb(struct file_system_type *fs_type,
        if (s->s_fs_info != server) {
                nfs_free_server(server);
                server = NULL;
+       } else {
+               error = nfs_bdi_register(server);
+               if (error)
+                       goto error_splat_bdi;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               s->s_flags = flags;
                nfs_fill_super(s, data);
+               nfs_fscache_get_super_cookie(
+                       s, data ? data->fscache_uniq : NULL, NULL);
        }
 
-       mntroot = nfs_get_root(s, &mntfh);
+       mntroot = nfs_get_root(s, mntfh);
        if (IS_ERR(mntroot)) {
                error = PTR_ERR(mntroot);
                goto error_splat_super;
        }
 
+       error = security_sb_set_mnt_opts(s, &data->lsm_opts);
+       if (error)
+               goto error_splat_root;
+
        s->s_flags |= MS_ACTIVE;
        mnt->mnt_sb = s;
        mnt->mnt_root = mntroot;
-       return 0;
+       error = 0;
+
+out:
+       kfree(data->nfs_server.hostname);
+       kfree(data->mount_server.hostname);
+       kfree(data->fscache_uniq);
+       security_free_mnt_opts(&data->lsm_opts);
+out_free_fh:
+       kfree(mntfh);
+       kfree(data);
+       return error;
 
 out_err_nosb:
        nfs_free_server(server);
-out_err_noserver:
-       return error;
+       goto out;
 
+error_splat_root:
+       dput(mntroot);
 error_splat_super:
-       up_write(&s->s_umount);
-       deactivate_super(s);
-       return error;
+       if (server && !s->s_root)
+               bdi_unregister(&server->backing_dev_info);
+error_splat_bdi:
+       deactivate_locked_super(s);
+       goto out;
+}
+
+/*
+ * Ensure that we unregister the bdi before kill_anon_super
+ * releases the device name
+ */
+static void nfs_put_super(struct super_block *s)
+{
+       struct nfs_server *server = NFS_SB(s);
+
+       bdi_unregister(&server->backing_dev_info);
 }
 
 /*
@@ -676,6 +2284,7 @@ static void nfs_kill_super(struct super_block *s)
        struct nfs_server *server = NFS_SB(s);
 
        kill_anon_super(s);
+       nfs_fscache_release_super_cookie(s);
        nfs_free_server(server);
 }
 
@@ -690,6 +2299,10 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
        struct super_block *s;
        struct nfs_server *server;
        struct dentry *mntroot;
+       int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
+       struct nfs_sb_mountdata sb_mntdata = {
+               .mntflags = flags,
+       };
        int error;
 
        dprintk("--> nfs_xdev_get_sb()\n");
@@ -700,9 +2313,13 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(server);
                goto out_err_noserver;
        }
+       sb_mntdata.server = server;
+
+       if (server->flags & NFS_MOUNT_UNSHARED)
+               compare_super = NULL;
 
        /* Get a superblock - note that we may end up sharing one that already exists */
-       s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+       s = sget(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
        if (IS_ERR(s)) {
                error = PTR_ERR(s);
                goto out_err_nosb;
@@ -711,12 +2328,16 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
        if (s->s_fs_info != server) {
                nfs_free_server(server);
                server = NULL;
+       } else {
+               error = nfs_bdi_register(server);
+               if (error)
+                       goto error_splat_bdi;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               s->s_flags = flags;
                nfs_clone_super(s, data->sb);
+               nfs_fscache_get_super_cookie(s, NULL, data);
        }
 
        mntroot = nfs_get_root(s, data->fh);
@@ -724,11 +2345,19 @@ static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(mntroot);
                goto error_splat_super;
        }
+       if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
+               dput(mntroot);
+               error = -ESTALE;
+               goto error_splat_super;
+       }
 
        s->s_flags |= MS_ACTIVE;
        mnt->mnt_sb = s;
        mnt->mnt_root = mntroot;
 
+       /* clone any lsm security options from the parent to the new sb */
+       security_sb_clone_mnt_opts(data->sb, s);
+
        dprintk("<-- nfs_xdev_get_sb() = 0\n");
        return 0;
 
@@ -739,8 +2368,10 @@ out_err_noserver:
        return error;
 
 error_splat_super:
-       up_write(&s->s_umount);
-       deactivate_super(s);
+       if (server && !s->s_root)
+               bdi_unregister(&server->backing_dev_info);
+error_splat_bdi:
+       deactivate_locked_super(s);
        dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error);
        return error;
 }
@@ -771,115 +2402,179 @@ static void nfs4_fill_super(struct super_block *sb)
        nfs_initialise_sb(sb);
 }
 
-static void *nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen)
+static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
 {
-       void *p = NULL;
-
-       if (!src->len)
-               return ERR_PTR(-EINVAL);
-       if (src->len < maxlen)
-               maxlen = src->len;
-       if (dst == NULL) {
-               p = dst = kmalloc(maxlen + 1, GFP_KERNEL);
-               if (p == NULL)
-                       return ERR_PTR(-ENOMEM);
-       }
-       if (copy_from_user(dst, src->data, maxlen)) {
-               kfree(p);
-               return ERR_PTR(-EFAULT);
-       }
-       dst[maxlen] = '\0';
-       return dst;
+       args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3);
 }
 
-/*
- * Get the superblock for an NFS4 mountpoint
- */
-static int nfs4_get_sb(struct file_system_type *fs_type,
-       int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
+static int nfs4_validate_text_mount_data(void *options,
+                                        struct nfs_parsed_mount_data *args,
+                                        const char *dev_name)
 {
-       struct nfs4_mount_data *data = raw_data;
-       struct super_block *s;
-       struct nfs_server *server;
-       struct sockaddr_in addr;
-       rpc_authflavor_t authflavour;
-       struct nfs_fh mntfh;
-       struct dentry *mntroot;
-       char *mntpath = NULL, *hostname = NULL, ip_addr[16];
-       void *p;
-       int error;
+       struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
+
+       nfs_set_port(sap, &args->nfs_server.port, NFS_PORT);
 
-       if (data == NULL) {
-               dprintk("%s: missing data argument\n", __FUNCTION__);
+       nfs_validate_transport_protocol(args);
+
+       nfs4_validate_mount_flags(args);
+
+       if (args->version != 4) {
+               dfprintk(MOUNT,
+                        "NFS4: Illegal mount version\n");
                return -EINVAL;
        }
-       if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) {
-               dprintk("%s: bad mount version\n", __FUNCTION__);
+
+       if (args->auth_flavor_len > 1) {
+               dfprintk(MOUNT,
+                        "NFS4: Too many RPC auth flavours specified\n");
                return -EINVAL;
        }
 
-       /* We now require that the mount process passes the remote address */
-       if (data->host_addrlen != sizeof(addr))
+       if (args->client_address == NULL) {
+               dfprintk(MOUNT,
+                        "NFS4: mount program didn't pass callback address\n");
                return -EINVAL;
+       }
 
-       if (copy_from_user(&addr, data->host_addr, sizeof(addr)))
-               return -EFAULT;
+       return nfs_parse_devname(dev_name,
+                                  &args->nfs_server.hostname,
+                                  NFS4_MAXNAMLEN,
+                                  &args->nfs_server.export_path,
+                                  NFS4_MAXPATHLEN);
+}
 
-       if (addr.sin_family != AF_INET ||
-           addr.sin_addr.s_addr == INADDR_ANY
-           ) {
-               dprintk("%s: mount program didn't pass remote IP address!\n",
-                               __FUNCTION__);
-               return -EINVAL;
-       }
-       /* RFC3530: The default port for NFS is 2049 */
-       if (addr.sin_port == 0)
-               addr.sin_port = htons(NFS_PORT);
-
-       /* Grab the authentication type */
-       authflavour = RPC_AUTH_UNIX;
-       if (data->auth_flavourlen != 0) {
-               if (data->auth_flavourlen != 1) {
-                       dprintk("%s: Invalid number of RPC auth flavours %d.\n",
-                                       __FUNCTION__, data->auth_flavourlen);
-                       error = -EINVAL;
-                       goto out_err_noserver;
-               }
+/*
+ * 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;
 
-               if (copy_from_user(&authflavour, data->auth_flavours,
-                                  sizeof(authflavour))) {
-                       error = -EFAULT;
-                       goto out_err_noserver;
+       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;
+
+               if (data->auth_flavourlen) {
+                       if (data->auth_flavourlen > 1)
+                               goto out_inval_auth;
+                       if (copy_from_user(&args->auth_flavors[0],
+                                          data->auth_flavours,
+                                          sizeof(args->auth_flavors[0])))
+                               return -EFAULT;
                }
+
+               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);
+
+               break;
+       default:
+               if (nfs_parse_mount_options((char *)options, args) == 0)
+                       return -EINVAL;
+
+               if (!nfs_verify_server_address(sap))
+                       return -EINVAL;
+
+               return nfs4_validate_text_mount_data(options, args, dev_name);
        }
 
-       p = nfs_copy_user_string(NULL, &data->hostname, 256);
-       if (IS_ERR(p))
-               goto out_err;
-       hostname = p;
+       return 0;
 
-       p = nfs_copy_user_string(NULL, &data->mnt_path, 1024);
-       if (IS_ERR(p))
-               goto out_err;
-       mntpath = p;
+out_no_data:
+       dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
+       return -EINVAL;
 
-       dprintk("MNTPATH: %s\n", mntpath);
+out_inval_auth:
+       dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
+                data->auth_flavourlen);
+       return -EINVAL;
 
-       p = nfs_copy_user_string(ip_addr, &data->client_addr,
-                                sizeof(ip_addr) - 1);
-       if (IS_ERR(p))
-               goto out_err;
+out_no_address:
+       dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
+       return -EINVAL;
+}
+
+/*
+ * Get the superblock for the NFS4 root partition
+ */
+static int nfs4_remote_get_sb(struct file_system_type *fs_type,
+       int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
+{
+       struct nfs_parsed_mount_data *data = raw_data;
+       struct super_block *s;
+       struct nfs_server *server;
+       struct nfs_fh *mntfh;
+       struct dentry *mntroot;
+       int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
+       struct nfs_sb_mountdata sb_mntdata = {
+               .mntflags = flags,
+       };
+       int error = -ENOMEM;
+
+       mntfh = kzalloc(sizeof(*mntfh), GFP_KERNEL);
+       if (data == NULL || mntfh == NULL)
+               goto out_free_fh;
+
+       security_init_mnt_opts(&data->lsm_opts);
 
        /* Get a volume representation */
-       server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr,
-                                   authflavour, &mntfh);
+       server = nfs4_create_server(data, mntfh);
        if (IS_ERR(server)) {
                error = PTR_ERR(server);
-               goto out_err_noserver;
+               goto out;
        }
+       sb_mntdata.server = server;
+
+       if (server->flags & NFS4_MOUNT_UNSHARED)
+               compare_super = NULL;
 
        /* Get a superblock - note that we may end up sharing one that already exists */
-       s = sget(fs_type, nfs_compare_super, nfs_set_super, server);
+       s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
        if (IS_ERR(s)) {
                error = PTR_ERR(s);
                goto out_free;
@@ -888,53 +2583,200 @@ static int nfs4_get_sb(struct file_system_type *fs_type,
        if (s->s_fs_info != server) {
                nfs_free_server(server);
                server = NULL;
+       } else {
+               error = nfs_bdi_register(server);
+               if (error)
+                       goto error_splat_bdi;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               s->s_flags = flags;
                nfs4_fill_super(s);
+               nfs_fscache_get_super_cookie(
+                       s, data ? data->fscache_uniq : NULL, NULL);
        }
 
-       mntroot = nfs4_get_root(s, &mntfh);
+       mntroot = nfs4_get_root(s, mntfh);
        if (IS_ERR(mntroot)) {
                error = PTR_ERR(mntroot);
                goto error_splat_super;
        }
 
+       error = security_sb_set_mnt_opts(s, &data->lsm_opts);
+       if (error)
+               goto error_splat_root;
+
        s->s_flags |= MS_ACTIVE;
        mnt->mnt_sb = s;
        mnt->mnt_root = mntroot;
-       kfree(mntpath);
-       kfree(hostname);
-       return 0;
+       error = 0;
 
-out_err:
-       error = PTR_ERR(p);
-       goto out_err_noserver;
+out:
+       security_free_mnt_opts(&data->lsm_opts);
+out_free_fh:
+       kfree(mntfh);
+       return error;
 
 out_free:
        nfs_free_server(server);
-out_err_noserver:
-       kfree(mntpath);
-       kfree(hostname);
-       return error;
+       goto out;
 
+error_splat_root:
+       dput(mntroot);
 error_splat_super:
-       up_write(&s->s_umount);
-       deactivate_super(s);
-       goto out_err_noserver;
+       if (server && !s->s_root)
+               bdi_unregister(&server->backing_dev_info);
+error_splat_bdi:
+       deactivate_locked_super(s);
+       goto out;
+}
+
+static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
+               int flags, void *data, const char *hostname)
+{
+       struct vfsmount *root_mnt;
+       char *root_devname;
+       size_t len;
+
+       len = strlen(hostname) + 3;
+       root_devname = kmalloc(len, GFP_KERNEL);
+       if (root_devname == NULL)
+               return ERR_PTR(-ENOMEM);
+       snprintf(root_devname, len, "%s:/", hostname);
+       root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
+       kfree(root_devname);
+       return root_mnt;
+}
+
+static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt)
+{
+       char *page = (char *) __get_free_page(GFP_KERNEL);
+       char *devname, *tmp;
+
+       if (page == NULL)
+               return;
+       devname = nfs_path(path->mnt->mnt_devname,
+                       path->mnt->mnt_root, path->dentry,
+                       page, PAGE_SIZE);
+       if (IS_ERR(devname))
+               goto out_freepage;
+       tmp = kstrdup(devname, GFP_KERNEL);
+       if (tmp == NULL)
+               goto out_freepage;
+       kfree(mnt->mnt_devname);
+       mnt->mnt_devname = tmp;
+out_freepage:
+       free_page((unsigned long)page);
+}
+
+static int nfs_follow_remote_path(struct vfsmount *root_mnt,
+               const char *export_path, struct vfsmount *mnt_target)
+{
+       struct mnt_namespace *ns_private;
+       struct nameidata nd;
+       struct super_block *s;
+       int ret;
+
+       ns_private = create_mnt_ns(root_mnt);
+       ret = PTR_ERR(ns_private);
+       if (IS_ERR(ns_private))
+               goto out_mntput;
+
+       ret = vfs_path_lookup(root_mnt->mnt_root, root_mnt,
+                       export_path, LOOKUP_FOLLOW, &nd);
+
+       put_mnt_ns(ns_private);
+
+       if (ret != 0)
+               goto out_err;
+
+       s = nd.path.mnt->mnt_sb;
+       atomic_inc(&s->s_active);
+       mnt_target->mnt_sb = s;
+       mnt_target->mnt_root = dget(nd.path.dentry);
+
+       /* Correct the device pathname */
+       nfs_fix_devname(&nd.path, mnt_target);
+
+       path_put(&nd.path);
+       down_write(&s->s_umount);
+       return 0;
+out_mntput:
+       mntput(root_mnt);
+out_err:
+       return ret;
+}
+
+static int nfs4_try_mount(int flags, const char *dev_name,
+                        struct nfs_parsed_mount_data *data,
+                        struct vfsmount *mnt)
+{
+       char *export_path;
+       struct vfsmount *root_mnt;
+       int error;
+
+       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, data,
+                       data->nfs_server.hostname);
+       data->nfs_server.export_path = export_path;
+
+       error = PTR_ERR(root_mnt);
+       if (IS_ERR(root_mnt))
+               goto out;
+
+       error = nfs_follow_remote_path(root_mnt, export_path, mnt);
+
+out:
+       dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n", error,
+                       error != 0 ? " [error]" : "");
+       return error;
+}
+
+/*
+ * Get the superblock for an NFS4 mountpoint
+ */
+static int nfs4_get_sb(struct file_system_type *fs_type,
+       int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt)
+{
+       struct nfs_parsed_mount_data *data;
+       int error = -ENOMEM;
+
+       data = nfs_alloc_parsed_mount_data(4);
+       if (data == NULL)
+               goto out_free_data;
+
+       /* Validate the mount data */
+       error = nfs4_validate_mount_data(raw_data, data, dev_name);
+       if (error < 0)
+               goto out;
+
+       error = nfs4_try_mount(flags, dev_name, data, mnt);
+
+out:
+       kfree(data->client_address);
+       kfree(data->nfs_server.export_path);
+       kfree(data->nfs_server.hostname);
+       kfree(data->fscache_uniq);
+out_free_data:
+       kfree(data);
+       dprintk("<-- nfs4_get_sb() = %d%s\n", error,
+                       error != 0 ? " [error]" : "");
+       return error;
 }
 
 static void nfs4_kill_super(struct super_block *sb)
 {
        struct nfs_server *server = NFS_SB(sb);
 
-       nfs_return_all_delegations(sb);
+       dprintk("--> %s\n", __func__);
+       nfs_super_return_all_delegations(sb);
        kill_anon_super(sb);
-
-       nfs4_renewd_prepare_shutdown(server);
+       nfs_fscache_release_super_cookie(sb);
        nfs_free_server(server);
+       dprintk("<-- %s\n", __func__);
 }
 
 /*
@@ -948,6 +2790,10 @@ static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
        struct super_block *s;
        struct nfs_server *server;
        struct dentry *mntroot;
+       int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
+       struct nfs_sb_mountdata sb_mntdata = {
+               .mntflags = flags,
+       };
        int error;
 
        dprintk("--> nfs4_xdev_get_sb()\n");
@@ -958,9 +2804,13 @@ static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(server);
                goto out_err_noserver;
        }
+       sb_mntdata.server = server;
+
+       if (server->flags & NFS4_MOUNT_UNSHARED)
+               compare_super = NULL;
 
        /* Get a superblock - note that we may end up sharing one that already exists */
-       s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+       s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
        if (IS_ERR(s)) {
                error = PTR_ERR(s);
                goto out_err_nosb;
@@ -969,12 +2819,16 @@ static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
        if (s->s_fs_info != server) {
                nfs_free_server(server);
                server = NULL;
+       } else {
+               error = nfs_bdi_register(server);
+               if (error)
+                       goto error_splat_bdi;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               s->s_flags = flags;
                nfs4_clone_super(s, data->sb);
+               nfs_fscache_get_super_cookie(s, NULL, data);
        }
 
        mntroot = nfs4_get_root(s, data->fh);
@@ -982,11 +2836,18 @@ static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(mntroot);
                goto error_splat_super;
        }
+       if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
+               dput(mntroot);
+               error = -ESTALE;
+               goto error_splat_super;
+       }
 
        s->s_flags |= MS_ACTIVE;
        mnt->mnt_sb = s;
        mnt->mnt_root = mntroot;
 
+       security_sb_clone_mnt_opts(data->sb, s);
+
        dprintk("<-- nfs4_xdev_get_sb() = 0\n");
        return 0;
 
@@ -997,24 +2858,27 @@ out_err_noserver:
        return error;
 
 error_splat_super:
-       up_write(&s->s_umount);
-       deactivate_super(s);
+       if (server && !s->s_root)
+               bdi_unregister(&server->backing_dev_info);
+error_splat_bdi:
+       deactivate_locked_super(s);
        dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error);
        return error;
 }
 
-/*
- * Create an NFS4 server record on referral traversal
- */
-static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
-                               const char *dev_name, void *raw_data,
-                               struct vfsmount *mnt)
+static int nfs4_remote_referral_get_sb(struct file_system_type *fs_type,
+               int flags, const char *dev_name, void *raw_data,
+               struct vfsmount *mnt)
 {
        struct nfs_clone_mount *data = raw_data;
        struct super_block *s;
        struct nfs_server *server;
        struct dentry *mntroot;
        struct nfs_fh mntfh;
+       int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
+       struct nfs_sb_mountdata sb_mntdata = {
+               .mntflags = flags,
+       };
        int error;
 
        dprintk("--> nfs4_referral_get_sb()\n");
@@ -1025,9 +2889,13 @@ static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(server);
                goto out_err_noserver;
        }
+       sb_mntdata.server = server;
+
+       if (server->flags & NFS4_MOUNT_UNSHARED)
+               compare_super = NULL;
 
        /* Get a superblock - note that we may end up sharing one that already exists */
-       s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server);
+       s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
        if (IS_ERR(s)) {
                error = PTR_ERR(s);
                goto out_err_nosb;
@@ -1036,12 +2904,16 @@ static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
        if (s->s_fs_info != server) {
                nfs_free_server(server);
                server = NULL;
+       } else {
+               error = nfs_bdi_register(server);
+               if (error)
+                       goto error_splat_bdi;
        }
 
        if (!s->s_root) {
                /* initial superblock/root creation */
-               s->s_flags = flags;
                nfs4_fill_super(s);
+               nfs_fscache_get_super_cookie(s, NULL, data);
        }
 
        mntroot = nfs4_get_root(s, &mntfh);
@@ -1049,11 +2921,18 @@ static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags,
                error = PTR_ERR(mntroot);
                goto error_splat_super;
        }
+       if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops) {
+               dput(mntroot);
+               error = -ESTALE;
+               goto error_splat_super;
+       }
 
        s->s_flags |= MS_ACTIVE;
        mnt->mnt_sb = s;
        mnt->mnt_root = mntroot;
 
+       security_sb_clone_mnt_opts(data->sb, s);
+
        dprintk("<-- nfs4_referral_get_sb() = 0\n");
        return 0;
 
@@ -1064,10 +2943,44 @@ out_err_noserver:
        return error;
 
 error_splat_super:
-       up_write(&s->s_umount);
-       deactivate_super(s);
+       if (server && !s->s_root)
+               bdi_unregister(&server->backing_dev_info);
+error_splat_bdi:
+       deactivate_locked_super(s);
        dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error);
        return error;
 }
 
+/*
+ * Create an NFS4 server record on referral traversal
+ */
+static int nfs4_referral_get_sb(struct file_system_type *fs_type,
+               int flags, const char *dev_name, void *raw_data,
+               struct vfsmount *mnt)
+{
+       struct nfs_clone_mount *data = raw_data;
+       char *export_path;
+       struct vfsmount *root_mnt;
+       int error;
+
+       dprintk("--> nfs4_referral_get_sb()\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;
+
+       error = PTR_ERR(root_mnt);
+       if (IS_ERR(root_mnt))
+               goto out;
+
+       error = nfs_follow_remote_path(root_mnt, export_path, mnt);
+out:
+       dprintk("<-- nfs4_referral_get_sb() = %d%s\n", error,
+                       error != 0 ? " [error]" : "");
+       return error;
+}
+
 #endif /* CONFIG_NFS_V4 */