new helper: ihold()

Clones an existing reference to inode; caller must already hold one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index f1ef97d..f7dbc06 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -2285,7 +2285,7 @@
 			goto slashes;
 		inode = dentry->d_inode;
 		if (inode)
-			atomic_inc(&inode->i_count);
+			ihold(inode);
 		error = mnt_want_write(nd.path.mnt);
 		if (error)
 			goto exit2;