split __lookup_mnt() in two functions
Instead of passing the direction as argument (and checking it on every
step through the hash chain), just have separate __lookup_mnt() and
__lookup_mnt_last(). And use the standard iterators...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namespace.c b/fs/namespace.c
index 5cbe8ce..500202c 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -548,29 +548,33 @@
}
/*
- * find the first or last mount at @dentry on vfsmount @mnt depending on
- * @dir. If @dir is set return the first mount else return the last mount.
+ * find the first mount at @dentry on vfsmount @mnt.
* vfsmount_lock must be held for read or write.
*/
-struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry,
- int dir)
+struct mount *__lookup_mnt(struct vfsmount *mnt, struct dentry *dentry)
{
struct list_head *head = mount_hashtable + hash(mnt, dentry);
- struct list_head *tmp = head;
- struct mount *p, *found = NULL;
+ struct mount *p;
- for (;;) {
- tmp = dir ? tmp->next : tmp->prev;
- p = NULL;
- if (tmp == head)
- break;
- p = list_entry(tmp, struct mount, mnt_hash);
- if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry) {
- found = p;
- break;
- }
- }
- return found;
+ list_for_each_entry(p, head, mnt_hash)
+ if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry)
+ return p;
+ return NULL;
+}
+
+/*
+ * find the last mount at @dentry on vfsmount @mnt.
+ * vfsmount_lock must be held for read or write.
+ */
+struct mount *__lookup_mnt_last(struct vfsmount *mnt, struct dentry *dentry)
+{
+ struct list_head *head = mount_hashtable + hash(mnt, dentry);
+ struct mount *p;
+
+ list_for_each_entry_reverse(p, head, mnt_hash)
+ if (&p->mnt_parent->mnt == mnt && p->mnt_mountpoint == dentry)
+ return p;
+ return NULL;
}
/*
@@ -594,7 +598,7 @@
struct mount *child_mnt;
br_read_lock(&vfsmount_lock);
- child_mnt = __lookup_mnt(path->mnt, path->dentry, 1);
+ child_mnt = __lookup_mnt(path->mnt, path->dentry);
if (child_mnt) {
mnt_add_count(child_mnt, 1);
br_read_unlock(&vfsmount_lock);