From 554fc4613ab6eaf61d90bcb039df6b941cb951a2 Mon Sep 17 00:00:00 2001
From: Nick Piggin <npiggin@kernel.dk>
Date: Fri, 7 Jan 2011 17:49:16 +1100
Subject: [PATCH] --- yaml --- r: 226688 b: refs/heads/master c:
 786a5e15b613a9cee4fc9139fc3113a5ab0fde79 h: refs/heads/master v: v3

---
 [refs]            |  2 +-
 trunk/fs/dcache.c | 25 +++++++------------------
 2 files changed, 8 insertions(+), 19 deletions(-)

diff --git a/[refs] b/[refs]
index a463dea003dd..3fa23127a87a 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d3a23e1678a5827c38ed8a465ad91d65e59fa911
+refs/heads/master: 786a5e15b613a9cee4fc9139fc3113a5ab0fde79
diff --git a/trunk/fs/dcache.c b/trunk/fs/dcache.c
index cc2b93802179..9d1a59dfda0b 100644
--- a/trunk/fs/dcache.c
+++ b/trunk/fs/dcache.c
@@ -1483,41 +1483,30 @@ struct dentry *d_hash_and_lookup(struct dentry *dir, struct qstr *name)
 }
 
 /**
- * d_validate - verify dentry provided from insecure source
+ * d_validate - verify dentry provided from insecure source (deprecated)
  * @dentry: The dentry alleged to be valid child of @dparent
  * @dparent: The parent dentry (known to be valid)
  *
  * An insecure source has sent us a dentry, here we verify it and dget() it.
  * This is used by ncpfs in its readdir implementation.
  * Zero is returned in the dentry is invalid.
+ *
+ * This function is slow for big directories, and deprecated, do not use it.
  */
- 
 int d_validate(struct dentry *dentry, struct dentry *dparent)
 {
-	struct hlist_head *base;
-	struct hlist_node *lhp;
-
-	/* Check whether the ptr might be valid at all.. */
-	if (!kmem_ptr_validate(dentry_cache, dentry))
-		goto out;
-
-	if (dentry->d_parent != dparent)
-		goto out;
+	struct dentry *child;
 
 	spin_lock(&dcache_lock);
-	base = d_hash(dparent, dentry->d_name.hash);
-	hlist_for_each(lhp,base) { 
-		/* hlist_for_each_entry_rcu() not required for d_hash list
-		 * as it is parsed under dcache_lock
-		 */
-		if (dentry == hlist_entry(lhp, struct dentry, d_hash)) {
+	list_for_each_entry(child, &dparent->d_subdirs, d_u.d_child) {
+		if (dentry == child) {
 			__dget_locked(dentry);
 			spin_unlock(&dcache_lock);
 			return 1;
 		}
 	}
 	spin_unlock(&dcache_lock);
-out:
+
 	return 0;
 }
 EXPORT_SYMBOL(d_validate);