NFS: Split out the NFS v4 filesystem types

This allows me to move the v4 mounting and unmounting functions out of
the generic client and into a file that is only compiled when CONFIG_NFS_V4
is enabled.

Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 381 insertions, 373 deletions

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index b4a35705246..cfafd13b6fe 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -153,6 +153,14 @@ struct nfs_mount_request {
         struct net              *net;
 };
 
+struct nfs_mount_info {
+        void (*fill_super)(struct super_block *, struct nfs_mount_info *);
+        int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
+        struct nfs_parsed_mount_data *parsed;
+        struct nfs_clone_mount *cloned;
+        struct nfs_fh *mntfh;
+};
+
 extern int nfs_mount(struct nfs_mount_request *info);
 extern void nfs_umount(const struct nfs_mount_request *info);
 
@@ -318,6 +326,16 @@ extern struct file_system_type nfs_xdev_fs_type;
 extern struct file_system_type nfs4_xdev_fs_type;
 extern struct file_system_type nfs4_referral_fs_type;
 #endif
+void nfs_initialise_sb(struct super_block *);
+int nfs_set_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
+int nfs_clone_sb_security(struct super_block *, struct dentry *, struct nfs_mount_info *);
+struct dentry *nfs_fs_mount_common(struct file_system_type *, struct nfs_server *,
+                                   int, const char *, struct nfs_mount_info *);
+struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
+struct dentry * nfs_xdev_mount_common(struct file_system_type *, int,
+                const char *, struct nfs_mount_info *);
+void nfs_kill_super(struct super_block *);
+void nfs_fill_super(struct super_block *, struct nfs_mount_info *);
 
 extern struct rpc_stat nfs_rpcstat;
 
@@ -364,6 +382,17 @@ extern void nfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
 extern void nfs_pageio_reset_read_mds(struct nfs_pageio_descriptor *pgio);
 extern void nfs_readdata_release(struct nfs_read_data *rdata);
 
+/* super.c */
+void nfs_clone_super(struct super_block *, struct nfs_mount_info *);
+void nfs_umount_begin(struct super_block *);
+int  nfs_statfs(struct dentry *, struct kstatfs *);
+int  nfs_show_options(struct seq_file *, struct dentry *);
+int  nfs_show_devname(struct seq_file *, struct dentry *);
+int  nfs_show_path(struct seq_file *, struct dentry *);
+int  nfs_show_stats(struct seq_file *, struct dentry *);
+void nfs_put_super(struct super_block *);
+int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
+
 /* write.c */
 extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
                         struct inode *inode, int ioflags,
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index b508fef1a32..b1ecacd8784 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -365,6 +365,8 @@ extern void nfs4_free_lock_state(struct nfs_server *server, struct nfs4_lock_sta
 extern const nfs4_stateid zero_stateid;
 
 /* nfs4super.c */
+struct nfs_mount_info;
+struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *);
 int init_nfs_v4(void);
 void exit_nfs_v4(void);
 
diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
index 70c394e75ca..2af26913884 100644
--- a/fs/nfs/nfs4super.c
+++ b/fs/nfs/nfs4super.c
@@ -2,10 +2,331 @@
  * Copyright (c) 2012 Bryan Schumaker <bjschuma@netapp.com>
  */
 #include <linux/init.h>
+#include <linux/module.h>
 #include <linux/nfs_idmap.h>
+#include <linux/nfs4_mount.h>
 #include <linux/nfs_fs.h>
+#include "internal.h"
 #include "nfs4_fs.h"
 
+#define NFSDBG_FACILITY         NFSDBG_VFS
+
+static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *raw_data);
+static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *raw_data);
+static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *raw_data);
+static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *raw_data);
+
+static struct file_system_type nfs4_fs_type = {
+        .owner          = THIS_MODULE,
+        .name           = "nfs4",
+        .mount          = nfs_fs_mount,
+        .kill_sb        = nfs_kill_super,
+        .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",
+        .mount          = nfs4_remote_mount,
+        .kill_sb        = nfs_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",
+        .mount          = nfs4_xdev_mount,
+        .kill_sb        = nfs_kill_super,
+        .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",
+        .mount          = nfs4_remote_referral_mount,
+        .kill_sb        = nfs_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",
+        .mount          = nfs4_referral_mount,
+        .kill_sb        = nfs_kill_super,
+        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
+};
+
+static const struct super_operations nfs4_sops = {
+        .alloc_inode    = nfs_alloc_inode,
+        .destroy_inode  = nfs_destroy_inode,
+        .write_inode    = nfs4_write_inode,
+        .put_super      = nfs_put_super,
+        .statfs         = nfs_statfs,
+        .evict_inode    = nfs4_evict_inode,
+        .umount_begin   = nfs_umount_begin,
+        .show_options   = nfs_show_options,
+        .show_devname   = nfs_show_devname,
+        .show_path      = nfs_show_path,
+        .show_stats     = nfs_show_stats,
+        .remount_fs     = nfs_remount,
+};
+
+/*
+ * Set up an NFS4 superblock
+ */
+static void nfs4_fill_super(struct super_block *sb,
+                            struct nfs_mount_info *mount_info)
+{
+        sb->s_time_gran = 1;
+        sb->s_op = &nfs4_sops;
+        /*
+         * The VFS shouldn't apply the umask to mode bits. We will do
+         * so ourselves when necessary.
+         */
+        sb->s_flags  |= MS_POSIXACL;
+        sb->s_xattr = nfs4_xattr_handlers;
+        nfs_initialise_sb(sb);
+}
+
+/*
+ * Get the superblock for the NFS4 root partition
+ */
+static struct dentry *
+nfs4_remote_mount(struct file_system_type *fs_type, int flags,
+                  const char *dev_name, void *info)
+{
+        struct nfs_mount_info *mount_info = info;
+        struct nfs_server *server;
+        struct dentry *mntroot = ERR_PTR(-ENOMEM);
+
+        mount_info->fill_super = nfs4_fill_super;
+        mount_info->set_security = nfs_set_sb_security;
+
+        /* Get a volume representation */
+        server = nfs4_create_server(mount_info->parsed, mount_info->mntfh);
+        if (IS_ERR(server)) {
+                mntroot = ERR_CAST(server);
+                goto out;
+        }
+
+        mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, mount_info);
+
+out:
+        return mntroot;
+}
+
+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) + 5;
+        root_devname = kmalloc(len, GFP_KERNEL);
+        if (root_devname == NULL)
+                return ERR_PTR(-ENOMEM);
+        /* Does hostname needs to be enclosed in brackets? */
+        if (strchr(hostname, ':'))
+                snprintf(root_devname, len, "[%s]:/", hostname);
+        else
+                snprintf(root_devname, len, "%s:/", hostname);
+        root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
+        kfree(root_devname);
+        return root_mnt;
+}
+
+struct nfs_referral_count {
+        struct list_head list;
+        const struct task_struct *task;
+        unsigned int referral_count;
+};
+
+static LIST_HEAD(nfs_referral_count_list);
+static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
+
+static struct nfs_referral_count *nfs_find_referral_count(void)
+{
+        struct nfs_referral_count *p;
+
+        list_for_each_entry(p, &nfs_referral_count_list, list) {
+                if (p->task == current)
+                        return p;
+        }
+        return NULL;
+}
+
+#define NFS_MAX_NESTED_REFERRALS 2
+
+static int nfs_referral_loop_protect(void)
+{
+        struct nfs_referral_count *p, *new;
+        int ret = -ENOMEM;
+
+        new = kmalloc(sizeof(*new), GFP_KERNEL);
+        if (!new)
+                goto out;
+        new->task = current;
+        new->referral_count = 1;
+
+        ret = 0;
+        spin_lock(&nfs_referral_count_list_lock);
+        p = nfs_find_referral_count();
+        if (p != NULL) {
+                if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
+                        ret = -ELOOP;
+                else
+                        p->referral_count++;
+        } else {
+                list_add(&new->list, &nfs_referral_count_list);
+                new = NULL;
+        }
+        spin_unlock(&nfs_referral_count_list_lock);
+        kfree(new);
+out:
+        return ret;
+}
+
+static void nfs_referral_loop_unprotect(void)
+{
+        struct nfs_referral_count *p;
+
+        spin_lock(&nfs_referral_count_list_lock);
+        p = nfs_find_referral_count();
+        p->referral_count--;
+        if (p->referral_count == 0)
+                list_del(&p->list);
+        else
+                p = NULL;
+        spin_unlock(&nfs_referral_count_list_lock);
+        kfree(p);
+}
+
+static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
+                const char *export_path)
+{
+        struct dentry *dentry;
+        int err;
+
+        if (IS_ERR(root_mnt))
+                return ERR_CAST(root_mnt);
+
+        err = nfs_referral_loop_protect();
+        if (err) {
+                mntput(root_mnt);
+                return ERR_PTR(err);
+        }
+
+        dentry = mount_subtree(root_mnt, export_path);
+        nfs_referral_loop_unprotect();
+
+        return dentry;
+}
+
+struct dentry *nfs4_try_mount(int flags, const char *dev_name,
+                         struct nfs_mount_info *mount_info)
+{
+        char *export_path;
+        struct vfsmount *root_mnt;
+        struct dentry *res;
+        struct nfs_parsed_mount_data *data = mount_info->parsed;
+
+        dfprintk(MOUNT, "--> nfs4_try_mount()\n");
+
+        mount_info->fill_super = nfs4_fill_super;
+
+        export_path = data->nfs_server.export_path;
+        data->nfs_server.export_path = "/";
+        root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,
+                        data->nfs_server.hostname);
+        data->nfs_server.export_path = export_path;
+
+        res = nfs_follow_remote_path(root_mnt, export_path);
+
+        dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
+                        IS_ERR(res) ? PTR_ERR(res) : 0,
+                        IS_ERR(res) ? " [error]" : "");
+        return res;
+}
+
+/*
+ * Clone an NFS4 server record on xdev traversal (FSID-change)
+ */
+static struct dentry *
+nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
+                 const char *dev_name, void *raw_data)
+{
+        struct nfs_mount_info mount_info = {
+                .fill_super = nfs_clone_super,
+                .set_security = nfs_clone_sb_security,
+                .cloned = raw_data,
+        };
+        return nfs_xdev_mount_common(&nfs4_fs_type, flags, dev_name, &mount_info);
+}
+
+static struct dentry *
+nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
+                           const char *dev_name, void *raw_data)
+{
+        struct nfs_mount_info mount_info = {
+                .fill_super = nfs4_fill_super,
+                .set_security = nfs_clone_sb_security,
+                .cloned = raw_data,
+        };
+        struct nfs_server *server;
+        struct dentry *mntroot = ERR_PTR(-ENOMEM);
+
+        dprintk("--> nfs4_referral_get_sb()\n");
+
+        mount_info.mntfh = nfs_alloc_fhandle();
+        if (mount_info.cloned == NULL || mount_info.mntfh == NULL)
+                goto out;
+
+        /* create a new volume representation */
+        server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh);
+        if (IS_ERR(server)) {
+                mntroot = ERR_CAST(server);
+                goto out;
+        }
+
+        mntroot = nfs_fs_mount_common(&nfs4_fs_type, server, flags, dev_name, &mount_info);
+out:
+        nfs_free_fhandle(mount_info.mntfh);
+        return mntroot;
+}
+
+/*
+ * Create an NFS4 server record on referral traversal
+ */
+static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
+                int flags, const char *dev_name, void *raw_data)
+{
+        struct nfs_clone_mount *data = raw_data;
+        char *export_path;
+        struct vfsmount *root_mnt;
+        struct dentry *res;
+
+        dprintk("--> nfs4_referral_mount()\n");
+
+        export_path = data->mnt_path;
+        data->mnt_path = "/";
+
+        root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
+                        flags, data, data->hostname);
+        data->mnt_path = export_path;
+
+        res = nfs_follow_remote_path(root_mnt, export_path);
+        dprintk("<-- nfs4_referral_mount() = %ld%s\n",
+                        IS_ERR(res) ? PTR_ERR(res) : 0,
+                        IS_ERR(res) ? " [error]" : "");
+        return res;
+}
+
+
 int __init init_nfs_v4(void)
 {
         int err;
@@ -18,7 +339,13 @@ int __init init_nfs_v4(void)
         if (err)
                 goto out1;
 
+        err = register_filesystem(&nfs4_fs_type);
+        if (err < 0)
+                goto out2;
+
         return 0;
+out2:
+        nfs4_unregister_sysctl();
 out1:
         nfs_idmap_quit();
 out:
@@ -27,6 +354,7 @@ out:
 
 void __exit exit_nfs_v4(void)
 {
+        unregister_filesystem(&nfs4_fs_type);
         nfs4_unregister_sysctl();
         nfs_idmap_quit();
 }
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index ca3c0e8cf77..95866a8c21b 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -278,29 +278,8 @@ static match_table_t nfs_vers_tokens = {
         { Opt_vers_err, NULL }
 };
 
-struct nfs_mount_info {
-        void (*fill_super)(struct super_block *, struct nfs_mount_info *);
-        int (*set_security)(struct super_block *, struct dentry *, struct nfs_mount_info *);
-        struct nfs_parsed_mount_data *parsed;
-        struct nfs_clone_mount *cloned;
-        struct nfs_fh *mntfh;
-};
-
-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 dentry *);
-static int  nfs_show_devname(struct seq_file *, struct dentry *);
-static int  nfs_show_path(struct seq_file *, struct dentry *);
-static int  nfs_show_stats(struct seq_file *, struct dentry *);
-static struct dentry *nfs_fs_mount_common(struct file_system_type *,
-                struct nfs_server *, int, const char *, struct nfs_mount_info *);
-static struct dentry *nfs_fs_mount(struct file_system_type *,
-                int, const char *, void *);
 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
                 int flags, const char *dev_name, void *raw_data);
-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,
@@ -337,71 +316,6 @@ static const struct super_operations nfs_sops = {
 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 static int nfs4_validate_mount_data(void *options,
         struct nfs_parsed_mount_data *args, const char *dev_name);
-static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
-        struct nfs_mount_info *mount_info);
-static struct dentry *nfs4_remote_mount(struct file_system_type *fs_type,
-        int flags, const char *dev_name, void *raw_data);
-static struct dentry *nfs4_xdev_mount(struct file_system_type *fs_type,
-        int flags, const char *dev_name, void *raw_data);
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
-        int flags, const char *dev_name, void *raw_data);
-static struct dentry *nfs4_remote_referral_mount(struct file_system_type *fs_type,
-        int flags, const char *dev_name, void *raw_data);
-
-static struct file_system_type nfs4_fs_type = {
-        .owner          = THIS_MODULE,
-        .name           = "nfs4",
-        .mount          = nfs_fs_mount,
-        .kill_sb        = nfs_kill_super,
-        .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",
-        .mount          = nfs4_remote_mount,
-        .kill_sb        = nfs_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",
-        .mount          = nfs4_xdev_mount,
-        .kill_sb        = nfs_kill_super,
-        .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",
-        .mount          = nfs4_remote_referral_mount,
-        .kill_sb        = nfs_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",
-        .mount          = nfs4_referral_mount,
-        .kill_sb        = nfs_kill_super,
-        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
-};
-
-static const struct super_operations nfs4_sops = {
-        .alloc_inode    = nfs_alloc_inode,
-        .destroy_inode  = nfs_destroy_inode,
-        .write_inode    = nfs4_write_inode,
-        .put_super      = nfs_put_super,
-        .statfs         = nfs_statfs,
-        .evict_inode    = nfs4_evict_inode,
-        .umount_begin   = nfs_umount_begin,
-        .show_options   = nfs_show_options,
-        .show_devname   = nfs_show_devname,
-        .show_path      = nfs_show_path,
-        .show_stats     = nfs_show_stats,
-        .remount_fs     = nfs_remount,
-};
 #endif
 
 static struct shrinker acl_shrinker = {
@@ -423,18 +337,9 @@ int __init register_nfs_fs(void)
         ret = nfs_register_sysctl();
         if (ret < 0)
                 goto error_1;
-#ifdef CONFIG_NFS_V4
-        ret = register_filesystem(&nfs4_fs_type);
-        if (ret < 0)
-                goto error_2;
-#endif
         register_shrinker(&acl_shrinker);
         return 0;
 
-#ifdef CONFIG_NFS_V4
-error_2:
-        nfs_unregister_sysctl();
-#endif
 error_1:
         unregister_filesystem(&nfs_fs_type);
 error_0:
@@ -447,9 +352,6 @@ error_0:
 void __exit unregister_nfs_fs(void)
 {
         unregister_shrinker(&acl_shrinker);
-#ifdef CONFIG_NFS_V4
-        unregister_filesystem(&nfs4_fs_type);
-#endif
         nfs_unregister_sysctl();
         unregister_filesystem(&nfs_fs_type);
 }
@@ -473,7 +375,7 @@ void nfs_sb_deactive(struct super_block *sb)
 /*
  * Deliver file system statistics to userspace
  */
-static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
         struct nfs_server *server = NFS_SB(dentry->d_sb);
         unsigned char blockbits;
@@ -756,7 +658,7 @@ static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 /*
  * Describe the mount options on this VFS mountpoint
  */
-static int nfs_show_options(struct seq_file *m, struct dentry *root)
+int nfs_show_options(struct seq_file *m, struct dentry *root)
 {
         struct nfs_server *nfss = NFS_SB(root->d_sb);
 
@@ -814,7 +716,7 @@ static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 }
 #endif
 
-static int nfs_show_devname(struct seq_file *m, struct dentry *root)
+int nfs_show_devname(struct seq_file *m, struct dentry *root)
 {
         char *page = (char *) __get_free_page(GFP_KERNEL);
         char *devname, *dummy;
@@ -830,7 +732,7 @@ static int nfs_show_devname(struct seq_file *m, struct dentry *root)
         return err;
 }
 
-static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
+int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 {
         seq_puts(m, "/");
         return 0;
@@ -839,7 +741,7 @@ static int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 /*
  * Present statistical information for this VFS mountpoint
  */
-static int nfs_show_stats(struct seq_file *m, struct dentry *root)
+int nfs_show_stats(struct seq_file *m, struct dentry *root)
 {
         int i, cpu;
         struct nfs_server *nfss = NFS_SB(root->d_sb);
@@ -932,7 +834,7 @@ static int nfs_show_stats(struct seq_file *m, struct dentry *root)
  * 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)
+void nfs_umount_begin(struct super_block *sb)
 {
         struct nfs_server *server;
         struct rpc_clnt *rpc;
@@ -2107,7 +2009,7 @@ nfs_compare_remount_data(struct nfs_server *nfss,
         return 0;
 }
 
-static int
+int
 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
 {
         int error;
@@ -2172,7 +2074,7 @@ out:
 /*
  * Initialise the common bits of the superblock
  */
-static inline void nfs_initialise_sb(struct super_block *sb)
+inline void nfs_initialise_sb(struct super_block *sb)
 {
         struct nfs_server *server = NFS_SB(sb);
 
@@ -2194,8 +2096,7 @@ static inline void nfs_initialise_sb(struct super_block *sb)
 /*
  * Finish setting up an NFS2/3 superblock
  */
-static void nfs_fill_super(struct super_block *sb,
-                           struct nfs_mount_info *mount_info)
+void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 {
         struct nfs_parsed_mount_data *data = mount_info->parsed;
         struct nfs_server *server = NFS_SB(sb);
@@ -2220,8 +2121,7 @@ static void nfs_fill_super(struct super_block *sb,
 /*
  * Finish setting up a cloned NFS2/3/4 superblock
  */
-static void nfs_clone_super(struct super_block *sb,
-                            struct nfs_mount_info *mount_info)
+void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 {
         const struct super_block *old_sb = mount_info->cloned->sb;
         struct nfs_server *server = NFS_SB(sb);
@@ -2381,14 +2281,14 @@ static int nfs_bdi_register(struct nfs_server *server)
         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
 }
 
-static int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
-                               struct nfs_mount_info *mount_info)
+int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
+                        struct nfs_mount_info *mount_info)
 {
         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
 }
 
-static int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
-                                 struct nfs_mount_info *mount_info)
+int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
+                          struct nfs_mount_info *mount_info)
 {
         /* clone any lsm security options from the parent to the new sb */
         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
@@ -2397,10 +2297,10 @@ static int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
         return 0;
 }
 
-static struct dentry *nfs_fs_mount_common(struct file_system_type *fs_type,
-                                          struct nfs_server *server,
-                                          int flags, const char *dev_name,
-                                          struct nfs_mount_info *mount_info)
+struct dentry *nfs_fs_mount_common(struct file_system_type *fs_type,
+                                   struct nfs_server *server,
+                                   int flags, const char *dev_name,
+                                   struct nfs_mount_info *mount_info)
 {
         struct super_block *s;
         struct dentry *mntroot = ERR_PTR(-ENOMEM);
@@ -2470,7 +2370,7 @@ error_splat_bdi:
         goto out;
 }
 
-static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
+struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
         int flags, const char *dev_name, void *raw_data)
 {
         struct nfs_mount_info mount_info = {
@@ -2511,7 +2411,7 @@ out:
  * Ensure that we unregister the bdi before kill_anon_super
  * releases the device name
  */
-static void nfs_put_super(struct super_block *s)
+void nfs_put_super(struct super_block *s)
 {
         struct nfs_server *server = NFS_SB(s);
 
@@ -2521,7 +2421,7 @@ static void nfs_put_super(struct super_block *s)
 /*
  * Destroy an NFS2/3 superblock
  */
-static void nfs_kill_super(struct super_block *s)
+void nfs_kill_super(struct super_block *s)
 {
         struct nfs_server *server = NFS_SB(s);
 
@@ -2533,7 +2433,7 @@ static void nfs_kill_super(struct super_block *s)
 /*
  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
  */
-static struct dentry *
+struct dentry *
 nfs_xdev_mount_common(struct file_system_type *fs_type, int flags,
                 const char *dev_name, struct nfs_mount_info *mount_info)
 {
@@ -2580,23 +2480,6 @@ nfs_xdev_mount(struct file_system_type *fs_type, int flags,
 
 #ifdef CONFIG_NFS_V4
 
-/*
- * Set up an NFS4 superblock
- */
-static void nfs4_fill_super(struct super_block *sb,
-                            struct nfs_mount_info *mount_info)
-{
-        sb->s_time_gran = 1;
-        sb->s_op = &nfs4_sops;
-        /*
-         * The VFS shouldn't apply the umask to mode bits. We will do
-         * so ourselves when necessary.
-         */
-        sb->s_flags  |= MS_POSIXACL;
-        sb->s_xattr = nfs4_xattr_handlers;
-        nfs_initialise_sb(sb);
-}
-
 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
 {
         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
@@ -2694,238 +2577,4 @@ out_no_address:
         return -EINVAL;
 }
 
-/*
- * Get the superblock for the NFS4 root partition
- */
-static struct dentry *
-nfs4_remote_mount(struct file_system_type *fs_type, int flags,
-                  const char *dev_name, void *info)
-{
-        struct nfs_mount_info *mount_info = info;
-        struct nfs_server *server;
-        struct dentry *mntroot = ERR_PTR(-ENOMEM);
-
-        mount_info->fill_super = nfs4_fill_super;
-        mount_info->set_security = nfs_set_sb_security;
-
-        /* Get a volume representation */
-        server = nfs4_create_server(mount_info->parsed, mount_info->mntfh);
-        if (IS_ERR(server)) {
-                mntroot = ERR_CAST(server);
-                goto out;
-        }
-
-        mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, mount_info);
-
-out:
-        return mntroot;
-}
-
-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) + 5;
-        root_devname = kmalloc(len, GFP_KERNEL);
-        if (root_devname == NULL)
-                return ERR_PTR(-ENOMEM);
-        /* Does hostname needs to be enclosed in brackets? */
-        if (strchr(hostname, ':'))
-                snprintf(root_devname, len, "[%s]:/", hostname);
-        else
-                snprintf(root_devname, len, "%s:/", hostname);
-        root_mnt = vfs_kern_mount(fs_type, flags, root_devname, data);
-        kfree(root_devname);
-        return root_mnt;
-}
-
-struct nfs_referral_count {
-        struct list_head list;
-        const struct task_struct *task;
-        unsigned int referral_count;
-};
-
-static LIST_HEAD(nfs_referral_count_list);
-static DEFINE_SPINLOCK(nfs_referral_count_list_lock);
-
-static struct nfs_referral_count *nfs_find_referral_count(void)
-{
-        struct nfs_referral_count *p;
-
-        list_for_each_entry(p, &nfs_referral_count_list, list) {
-                if (p->task == current)
-                        return p;
-        }
-        return NULL;
-}
-
-#define NFS_MAX_NESTED_REFERRALS 2
-
-static int nfs_referral_loop_protect(void)
-{
-        struct nfs_referral_count *p, *new;
-        int ret = -ENOMEM;
-
-        new = kmalloc(sizeof(*new), GFP_KERNEL);
-        if (!new)
-                goto out;
-        new->task = current;
-        new->referral_count = 1;
-
-        ret = 0;
-        spin_lock(&nfs_referral_count_list_lock);
-        p = nfs_find_referral_count();
-        if (p != NULL) {
-                if (p->referral_count >= NFS_MAX_NESTED_REFERRALS)
-                        ret = -ELOOP;
-                else
-                        p->referral_count++;
-        } else {
-                list_add(&new->list, &nfs_referral_count_list);
-                new = NULL;
-        }
-        spin_unlock(&nfs_referral_count_list_lock);
-        kfree(new);
-out:
-        return ret;
-}
-
-static void nfs_referral_loop_unprotect(void)
-{
-        struct nfs_referral_count *p;
-
-        spin_lock(&nfs_referral_count_list_lock);
-        p = nfs_find_referral_count();
-        p->referral_count--;
-        if (p->referral_count == 0)
-                list_del(&p->list);
-        else
-                p = NULL;
-        spin_unlock(&nfs_referral_count_list_lock);
-        kfree(p);
-}
-
-static struct dentry *nfs_follow_remote_path(struct vfsmount *root_mnt,
-                const char *export_path)
-{
-        struct dentry *dentry;
-        int err;
-
-        if (IS_ERR(root_mnt))
-                return ERR_CAST(root_mnt);
-
-        err = nfs_referral_loop_protect();
-        if (err) {
-                mntput(root_mnt);
-                return ERR_PTR(err);
-        }
-
-        dentry = mount_subtree(root_mnt, export_path);
-        nfs_referral_loop_unprotect();
-
-        return dentry;
-}
-
-static struct dentry *nfs4_try_mount(int flags, const char *dev_name,
-                         struct nfs_mount_info *mount_info)
-{
-        char *export_path;
-        struct vfsmount *root_mnt;
-        struct dentry *res;
-        struct nfs_parsed_mount_data *data = mount_info->parsed;
-
-        dfprintk(MOUNT, "--> nfs4_try_mount()\n");
-
-        mount_info->fill_super = nfs4_fill_super;
-
-        export_path = data->nfs_server.export_path;
-        data->nfs_server.export_path = "/";
-        root_mnt = nfs_do_root_mount(&nfs4_remote_fs_type, flags, mount_info,
-                        data->nfs_server.hostname);
-        data->nfs_server.export_path = export_path;
-
-        res = nfs_follow_remote_path(root_mnt, export_path);
-
-        dfprintk(MOUNT, "<-- nfs4_try_mount() = %ld%s\n",
-                        IS_ERR(res) ? PTR_ERR(res) : 0,
-                        IS_ERR(res) ? " [error]" : "");
-        return res;
-}
-
-/*
- * Clone an NFS4 server record on xdev traversal (FSID-change)
- */
-static struct dentry *
-nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
-                 const char *dev_name, void *raw_data)
-{
-        struct nfs_mount_info mount_info = {
-                .fill_super = nfs_clone_super,
-                .set_security = nfs_clone_sb_security,
-                .cloned = raw_data,
-        };
-        return nfs_xdev_mount_common(&nfs4_fs_type, flags, dev_name, &mount_info);
-}
-
-static struct dentry *
-nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
-                           const char *dev_name, void *raw_data)
-{
-        struct nfs_mount_info mount_info = {
-                .fill_super = nfs4_fill_super,
-                .set_security = nfs_clone_sb_security,
-                .cloned = raw_data,
-        };
-        struct nfs_server *server;
-        struct dentry *mntroot = ERR_PTR(-ENOMEM);
-
-        dprintk("--> nfs4_referral_get_sb()\n");
-
-        mount_info.mntfh = nfs_alloc_fhandle();
-        if (mount_info.cloned == NULL || mount_info.mntfh == NULL)
-                goto out;
-
-        /* create a new volume representation */
-        server = nfs4_create_referral_server(mount_info.cloned, mount_info.mntfh);
-        if (IS_ERR(server)) {
-                mntroot = ERR_CAST(server);
-                goto out;
-        }
-
-        mntroot = nfs_fs_mount_common(&nfs4_fs_type, server, flags, dev_name, &mount_info);
-out:
-        nfs_free_fhandle(mount_info.mntfh);
-        return mntroot;
-}
-
-/*
- * Create an NFS4 server record on referral traversal
- */
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
-                int flags, const char *dev_name, void *raw_data)
-{
-        struct nfs_clone_mount *data = raw_data;
-        char *export_path;
-        struct vfsmount *root_mnt;
-        struct dentry *res;
-
-        dprintk("--> nfs4_referral_mount()\n");
-
-        export_path = data->mnt_path;
-        data->mnt_path = "/";
-
-        root_mnt = nfs_do_root_mount(&nfs4_remote_referral_fs_type,
-                        flags, data, data->hostname);
-        data->mnt_path = export_path;
-
-        res = nfs_follow_remote_path(root_mnt, export_path);
-        dprintk("<-- nfs4_referral_mount() = %ld%s\n",
-                        IS_ERR(res) ? PTR_ERR(res) : 0,
-                        IS_ERR(res) ? " [error]" : "");
-        return res;
-}
-
 #endif /* CONFIG_NFS_V4 */