vfs: remove unused have_submounts() function

Now that path_has_submounts() has been added have_submounts() is no
longer used so remove it.

Link: http://lkml.kernel.org/r/20161011053428.27645.12310.stgit@pluto.themaw.net
Signed-off-by: Ian Kent <raven@themaw.net>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/dcache.c

@@ -1273,39 +1273,6 @@ rename_retry:
 	goto again;
 }
 
-/*
- * Search for at least 1 mount point in the dentry's subdirs.
- * We descend to the next level whenever the d_subdirs
- * list is non-empty and continue searching.
- */
-
-static enum d_walk_ret check_mount(void *data, struct dentry *dentry)
-{
-	int *ret = data;
-	if (d_mountpoint(dentry)) {
-		*ret = 1;
-		return D_WALK_QUIT;
-	}
-	return D_WALK_CONTINUE;
-}
-
-/**
- * have_submounts - check for mounts over a dentry
- * @parent: dentry to check.
- *
- * Return true if the parent or its subdirectories contain
- * a mount point
- */
-int have_submounts(struct dentry *parent)
-{
-	int ret = 0;
-
-	d_walk(parent, &ret, check_mount, NULL);
-
-	return ret;
-}
-EXPORT_SYMBOL(have_submounts);
-
 struct check_mount {
 	struct vfsmount *mnt;
 	unsigned int mounted;

include/linux/dcache.h

@@ -254,7 +254,6 @@ extern struct dentry *d_find_alias(struct inode *);
 extern void d_prune_aliases(struct inode *);
 
 /* test whether we have any submounts in a subdir tree */
-extern int have_submounts(struct dentry *);
 extern int path_has_submounts(const struct path *);
 
 /*