new helper: mount_bdev()

... and switch of the obvious get_sb_bdev() users to ->mount()

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

1 files changed, 21 insertions, 7 deletions

diff --git a/fs/super.c b/fs/super.c
index 00a2c9662b55..40989e9a2606 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -762,10 +762,9 @@ static int test_bdev_super(struct super_block *s, void *data)
         return (void *)s->s_bdev == data;
 }
 
-int get_sb_bdev(struct file_system_type *fs_type,
+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),
-        struct vfsmount *mnt)
+        int (*fill_super)(struct super_block *, void *, int))
 {
         struct block_device *bdev;
         struct super_block *s;
@@ -777,7 +776,7 @@ int get_sb_bdev(struct file_system_type *fs_type,
 
         bdev = open_bdev_exclusive(dev_name, mode, fs_type);
         if (IS_ERR(bdev))
-                return PTR_ERR(bdev);
+                return ERR_CAST(bdev);
 
         /*
          * once the super is inserted into the list by sget, s_umount
@@ -829,15 +828,30 @@ int get_sb_bdev(struct file_system_type *fs_type,
                 bdev->bd_super = s;
         }
 
-        simple_set_mnt(mnt, s);
-        return 0;
+        return dget(s->s_root);
 
 error_s:
         error = PTR_ERR(s);
 error_bdev:
         close_bdev_exclusive(bdev, mode);
 error:
-        return error;
+        return ERR_PTR(error);
+}
+EXPORT_SYMBOL(mount_bdev);
+
+int get_sb_bdev(struct file_system_type *fs_type,
+        int flags, const char *dev_name, void *data,
+        int (*fill_super)(struct super_block *, void *, int),
+        struct vfsmount *mnt)
+{
+        struct dentry *root;
+
+        root = mount_bdev(fs_type, flags, dev_name, data, fill_super);
+        if (IS_ERR(root))
+                return PTR_ERR(root);
+        mnt->mnt_root = root;
+        mnt->mnt_sb = root->d_sb;
+        return 0;
 }
 
 EXPORT_SYMBOL(get_sb_bdev);