nilfs2: see state of root dentry for mount check of snapshots

After applied the patch that unified sb instances, root dentry of
snapshots can be left in dcache even after their trees are unmounted.

The orphan root dentry/inode keeps a root object, and this causes
false positive of nilfs_checkpoint_is_mounted function.

This resolves the issue by having nilfs_checkpoint_is_mounted test
whether the root dentry is busy or not.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

1 files changed, 0 insertions, 21 deletions

diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index 4d6763e28eb5..4cc705a1d135 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -769,24 +769,3 @@ void nilfs_put_root(struct nilfs_root *root)
                 kfree(root);
         }
 }
-
-int nilfs_checkpoint_is_mounted(struct the_nilfs *nilfs, __u64 cno,
-                                int snapshot_mount)
-{
-        struct nilfs_root *root;
-        int ret;
-
-        if (cno < 0 || cno > nilfs->ns_cno)
-                return false;
-
-        if (cno >= nilfs_last_cno(nilfs))
-                return true;    /* protect recent checkpoints */
-
-        ret = false;
-        root = nilfs_lookup_root(nilfs, cno);
-        if (root) {
-                ret = true;
-                nilfs_put_root(root);
-        }
-        return ret;
-}