stubs for mount_bdev() and kill_block_super() in !CONFIG_BLOCK case

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

include/linux/fs.h

@@ -2094,9 +2094,18 @@ struct file_system_type {
 extern struct dentry *mount_ns(struct file_system_type *fs_type,
 	int flags, void *data, void *ns, struct user_namespace *user_ns,
 	int (*fill_super)(struct super_block *, void *, int));
+#ifdef CONFIG_BLOCK
 extern struct dentry *mount_bdev(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *data,
 	int (*fill_super)(struct super_block *, void *, int));
+#else
+static inline struct dentry *mount_bdev(struct file_system_type *fs_type,
+	int flags, const char *dev_name, void *data,
+	int (*fill_super)(struct super_block *, void *, int))
+{
+	return ERR_PTR(-ENODEV);
+}
+#endif
 extern struct dentry *mount_single(struct file_system_type *fs_type,
 	int flags, void *data,
 	int (*fill_super)(struct super_block *, void *, int));
@@ -2105,7 +2114,14 @@ extern struct dentry *mount_nodev(struct file_system_type *fs_type,
 	int (*fill_super)(struct super_block *, void *, int));
 extern struct dentry *mount_subtree(struct vfsmount *mnt, const char *path);
 void generic_shutdown_super(struct super_block *sb);
+#ifdef CONFIG_BLOCK
 void kill_block_super(struct super_block *sb);
+#else
+static inline void kill_block_super(struct super_block *sb)
+{
+	BUG();
+}
+#endif
 void kill_anon_super(struct super_block *sb);
 void kill_litter_super(struct super_block *sb);
 void deactivate_super(struct super_block *sb);