NFS: Use nfs_fs_mount_common() for xdev mounts

At this point, there are only a few small differences between these two
functions.  I can set a few function pointers in the nfs_mount_info
struct to get around these differences.

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

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 707d1f67fb32a28a4093911fbce9c79dd838b63b..e93a6e95c031e21add44911aa57bce8c42c65938 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -279,6 +279,7 @@ static match_table_t nfs_vers_tokens = {
 
 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;
 };
@@ -2312,6 +2313,22 @@ 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)
+{
+       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)
+{
+       /* clone any lsm security options from the parent to the new sb */
+       security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
+       if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
+               return -ESTALE;
+       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,
@@ -2355,14 +2372,14 @@ static struct dentry *nfs_fs_mount_common(struct file_system_type *fs_type,
        if (!s->s_root) {
                /* initial superblock/root creation */
                mount_info->fill_super(s, mount_info);
-               nfs_get_cache_cookie(s, mount_info->parsed, NULL);
+               nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
        }
 
        mntroot = nfs_get_root(s, mntfh, dev_name);
        if (IS_ERR(mntroot))
                goto error_splat_super;
 
-       error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
+       error = mount_info->set_security(s, mntroot, mount_info);
        if (error)
                goto error_splat_root;
 
@@ -2393,6 +2410,7 @@ static struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
        struct nfs_parsed_mount_data *data = NULL;
        struct nfs_mount_info mount_info = {
                .fill_super = nfs_fill_super,
+               .set_security = nfs_set_sb_security,
        };
        struct nfs_fh *mntfh;
        struct dentry *mntroot = ERR_PTR(-ENOMEM);
@@ -2463,13 +2481,8 @@ nfs_xdev_mount_common(struct file_system_type *fs_type, int flags,
                const char *dev_name, struct nfs_mount_info *mount_info)
 {
        struct nfs_clone_mount *data = mount_info->cloned;
-       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,
-       };
+       struct dentry *mntroot = ERR_PTR(-ENOMEM);
        int error;
 
        dprintk("--> nfs_xdev_mount_common()\n");
@@ -2478,71 +2491,17 @@ nfs_xdev_mount_common(struct file_system_type *fs_type, int flags,
        server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
        if (IS_ERR(server)) {
                error = PTR_ERR(server);
-               goto out_err_noserver;
-       }
-       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(&nfs_fs_type, compare_super, nfs_set_super, &sb_mntdata);
-       if (IS_ERR(s)) {
-               error = PTR_ERR(s);
-               goto out_err_nosb;
-       }
-
-       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 */
-               mount_info->fill_super(s, mount_info);
-               nfs_get_cache_cookie(s, NULL, data);
-       }
-
-       mntroot = nfs_get_root(s, data->fh, dev_name);
-       if (IS_ERR(mntroot)) {
-               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;
+               goto out_err;
        }
 
-       s->s_flags |= MS_ACTIVE;
-
-       /* clone any lsm security options from the parent to the new sb */
-       security_sb_clone_mnt_opts(data->sb, s);
-
+       mntroot = nfs_fs_mount_common(fs_type, server, flags, dev_name, data->fh, mount_info);
        dprintk("<-- nfs_xdev_mount_common() = 0\n");
+out:
        return mntroot;
 
-out_err_nosb:
-       nfs_free_server(server);
-out_err_noserver:
+out_err:
        dprintk("<-- nfs_xdev_mount_common() = %d [error]\n", error);
-       return ERR_PTR(error);
-
-error_splat_super:
-       if (server && !s->s_root)
-               bdi_unregister(&server->backing_dev_info);
-error_splat_bdi:
-       deactivate_locked_super(s);
-       dprintk("<-- nfs_xdev_mount_common() = %d [splat]\n", error);
-       return ERR_PTR(error);
+       goto out;
 }
 
 /*
@@ -2554,6 +2513,7 @@ nfs_xdev_mount(struct file_system_type *fs_type, int flags,
 {
        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(&nfs_fs_type, flags, dev_name, &mount_info);
@@ -2740,6 +2700,7 @@ nfs4_remote_mount(struct file_system_type *fs_type, int flags,
 {
        struct nfs_mount_info mount_info = {
                .fill_super = nfs4_fill_super,
+               .set_security = nfs_set_sb_security,
                .parsed = raw_data,
        };
        struct nfs_server *server;
@@ -2949,6 +2910,7 @@ nfs4_xdev_mount(struct file_system_type *fs_type, int flags,
 {
        struct nfs_mount_info mount_info = {
                .fill_super = nfs4_clone_super,
+               .set_security = nfs_clone_sb_security,
                .cloned = raw_data,
        };
        return nfs_xdev_mount_common(&nfs4_fs_type, flags, dev_name, &mount_info);