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Date: Mon, 27 Dec 2010 18:46:41 -0500
From: "J. Bruce Fields" <bfields@fieldses.org>
To: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Nick Piggin <npiggin@kernel.dk>, linux-nfs@vger.kernel.org,
	linux-fsdevel@vger.kernel.org
Subject: [PATCH] fs/dcache: allow __d_obtain_alias() to return unhashed
	dentries
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diff --git a/fs/dcache.c b/fs/dcache.c
index 5ed93cd..5c014a5 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1135,6 +1135,28 @@ static inline struct hlist_head *d_hash(struct dentry *parent,
 	return dentry_hashtable + (hash & D_HASHMASK);
 }
 
+static struct dentry * __d_find_any_alias(struct inode *inode)
+{
+	struct dentry *alias;
+
+	if (list_empty(&inode->i_dentry))
+		return NULL;
+	alias = list_first_entry(&inode->i_dentry, struct dentry, d_alias);
+	__dget_locked(alias);
+	return alias;
+}
+
+static struct dentry * d_find_any_alias(struct inode *inode)
+{
+	struct dentry *de;
+
+	spin_lock(&dcache_lock);
+	de = __d_find_any_alias(inode);
+	spin_unlock(&dcache_lock);
+	return de;
+}
+
+
 /**
  * d_obtain_alias - find or allocate a dentry for a given inode
  * @inode: inode to allocate the dentry for
@@ -1164,7 +1186,7 @@ struct dentry *d_obtain_alias(struct inode *inode)
 	if (IS_ERR(inode))
 		return ERR_CAST(inode);
 
-	res = d_find_alias(inode);
+	res = d_find_any_alias(inode);
 	if (res)
 		goto out_iput;
 
@@ -1176,7 +1198,7 @@ struct dentry *d_obtain_alias(struct inode *inode)
 	tmp->d_parent = tmp; /* make sure dput doesn't croak */
 
 	spin_lock(&dcache_lock);
-	res = __d_find_alias(inode, 0);
+	res = __d_find_any_alias(inode);
 	if (res) {
 		spin_unlock(&dcache_lock);
 		dput(tmp);