NFS: Create a common fs_mount() function

The nfs4_remote_mount() function was only slightly different from the
nfs_fs_mount() function used by the generic client.  I created a new
nfs_mount_info structure to set different parameters to help combine
these functions.

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

1 files changed, 76 insertions, 109 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 40d43e05af03..64a62da6612d 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -277,6 +277,11 @@ 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 *);
+        struct nfs_parsed_mount_data *parsed;
+};
+
 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 *);
@@ -2129,8 +2134,9 @@ 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_parsed_mount_data *data)
+                           struct nfs_mount_info *mount_info)
 {
+        struct nfs_parsed_mount_data *data = mount_info->parsed;
         struct nfs_server *server = NFS_SB(sb);
 
         sb->s_blocksize_bits = 0;
@@ -2304,47 +2310,21 @@ static int nfs_bdi_register(struct nfs_server *server)
         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
 }
 
-static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
-        int flags, const char *dev_name, void *raw_data)
+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_fh *mntfh,
+                                          struct nfs_mount_info *mount_info)
 {
-        struct nfs_server *server = NULL;
         struct super_block *s;
-        struct nfs_parsed_mount_data *data;
-        struct nfs_fh *mntfh;
         struct dentry *mntroot = ERR_PTR(-ENOMEM);
         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
         struct nfs_sb_mountdata sb_mntdata = {
                 .mntflags = flags,
+                .server = server,
         };
         int error;
 
-        data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
-        mntfh = nfs_alloc_fhandle();
-        if (data == NULL || mntfh == NULL)
-                goto out;
-
-        /* Validate the mount data */
-        error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
-        if (error < 0) {
-                mntroot = ERR_PTR(error);
-                goto out;
-        }
-
-#ifdef CONFIG_NFS_V4
-        if (data->version == 4) {
-                mntroot = nfs4_try_mount(flags, dev_name, data);
-                goto out;
-        }
-#endif  /* CONFIG_NFS_V4 */
-
-        /* Get a volume representation */
-        server = nfs_create_server(data, mntfh);
-        if (IS_ERR(server)) {
-                mntroot = ERR_CAST(server);
-                goto out;
-        }
-        sb_mntdata.server = server;
-
         if (server->flags & NFS_MOUNT_UNSHARED)
                 compare_super = NULL;
 
@@ -2372,23 +2352,21 @@ static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
 
         if (!s->s_root) {
                 /* initial superblock/root creation */
-                nfs_fill_super(s, data);
-                nfs_get_cache_cookie(s, data, NULL);
+                mount_info->fill_super(s, mount_info);
+                nfs_get_cache_cookie(s, mount_info->parsed, NULL);
         }
 
         mntroot = nfs_get_root(s, mntfh, dev_name);
         if (IS_ERR(mntroot))
                 goto error_splat_super;
 
-        error = security_sb_set_mnt_opts(s, &data->lsm_opts);
+        error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
         if (error)
                 goto error_splat_root;
 
         s->s_flags |= MS_ACTIVE;
 
 out:
-        nfs_free_parsed_mount_data(data);
-        nfs_free_fhandle(mntfh);
         return mntroot;
 
 out_err_nosb:
@@ -2406,6 +2384,52 @@ error_splat_bdi:
         goto out;
 }
 
+static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *raw_data)
+{
+        struct nfs_server *server;
+        struct nfs_parsed_mount_data *data = NULL;
+        struct nfs_mount_info mount_info = {
+                .fill_super = nfs_fill_super,
+        };
+        struct nfs_fh *mntfh;
+        struct dentry *mntroot = ERR_PTR(-ENOMEM);
+        int error;
+
+        data = nfs_alloc_parsed_mount_data(NFS_DEFAULT_VERSION);
+        mntfh = nfs_alloc_fhandle();
+        if (data == NULL || mntfh == NULL)
+                goto out;
+
+        /* Validate the mount data */
+        error = nfs_validate_mount_data(raw_data, data, mntfh, dev_name);
+        if (error < 0) {
+                mntroot = ERR_PTR(error);
+                goto out;
+        }
+        mount_info.parsed = data;
+
+#ifdef CONFIG_NFS_V4
+        if (data->version == 4) {
+                mntroot = nfs4_try_mount(flags, dev_name, data);
+                goto out;
+        }
+#endif  /* CONFIG_NFS_V4 */
+
+        /* Get a volume representation */
+        server = nfs_create_server(data, mntfh);
+        if (IS_ERR(server)) {
+                mntroot = ERR_CAST(server);
+                goto out;
+        }
+
+        mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, mntfh, &mount_info);
+out:
+        nfs_free_parsed_mount_data(data);
+        nfs_free_fhandle(mntfh);
+        return mntroot;
+}
+
 /*
  * Ensure that we unregister the bdi before kill_anon_super
  * releases the device name
@@ -2544,7 +2568,8 @@ static void nfs4_clone_super(struct super_block *sb,
 /*
  * Set up an NFS4 superblock
  */
-static void nfs4_fill_super(struct super_block *sb)
+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;
@@ -2696,89 +2721,31 @@ static struct dentry *
 nfs4_remote_mount(struct file_system_type *fs_type, int flags,
                   const char *dev_name, void *raw_data)
 {
-        struct nfs_parsed_mount_data *data = raw_data;
-        struct super_block *s;
+        struct nfs_mount_info mount_info = {
+                .fill_super = nfs4_fill_super,
+                .parsed = raw_data,
+        };
         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;
+        struct dentry *mntroot = ERR_PTR(-ENOMEM);
 
         mntfh = nfs_alloc_fhandle();
-        if (data == NULL || mntfh == NULL)
+        if (mount_info.parsed == NULL || mntfh == NULL)
                 goto out;
 
         /* Get a volume representation */
-        server = nfs4_create_server(data, mntfh);
+        server = nfs4_create_server(mount_info.parsed, mntfh);
         if (IS_ERR(server)) {
-                error = PTR_ERR(server);
+                mntroot = ERR_CAST(server);
                 goto out;
         }
-        sb_mntdata.server = server;
 
-        if (server->flags & NFS_MOUNT_UNSHARED)
-                compare_super = NULL;
-
-        /* -o noac implies -o sync */
-        if (server->flags & NFS_MOUNT_NOAC)
-                sb_mntdata.mntflags |= MS_SYNCHRONOUS;
-
-        /* Get a superblock - note that we may end up sharing one that already exists */
-        s = sget(&nfs4_fs_type, compare_super, nfs_set_super, &sb_mntdata);
-        if (IS_ERR(s)) {
-                error = PTR_ERR(s);
-                goto out_free;
-        }
-
-        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 */
-                nfs4_fill_super(s);
-                nfs_get_cache_cookie(s, data, NULL);
-        }
-
-        mntroot = nfs_get_root(s, mntfh, dev_name);
-        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;
-
-        nfs_free_fhandle(mntfh);
-        return mntroot;
+        mntroot = nfs_fs_mount_common(fs_type, server, flags,
+                                      dev_name, mntfh, &mount_info);
 
 out:
         nfs_free_fhandle(mntfh);
-        return ERR_PTR(error);
-
-out_free:
-        nfs_free_server(server);
-        goto out;
-
-error_splat_root:
-        dput(mntroot);
-error_splat_super:
-        if (server && !s->s_root)
-                bdi_unregister(&server->backing_dev_info);
-error_splat_bdi:
-        deactivate_locked_super(s);
-        goto out;
+        return mntroot;
 }
 
 static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type,
@@ -3099,7 +3066,7 @@ nfs4_remote_referral_mount(struct file_system_type *fs_type, int flags,
 
         if (!s->s_root) {
                 /* initial superblock/root creation */
-                nfs4_fill_super(s);
+                nfs4_fill_super(s, NULL);
                 nfs_get_cache_cookie(s, NULL, data);
         }