1 files changed, 42 insertions, 10 deletions

diff --git a/fs/ocfs2/dcache.c b/fs/ocfs2/dcache.c
index b4957c7d9fe2..6d80ecc7834f 100644
--- a/fs/ocfs2/dcache.c
+++ b/fs/ocfs2/dcache.c
@@ -40,22 +40,45 @@
 #include "inode.h"
 #include "super.h"
 
+void ocfs2_dentry_attach_gen(struct dentry *dentry)
+{
+	unsigned long gen =
+		OCFS2_I(dentry->d_parent->d_inode)->ip_dir_lock_gen;
+	BUG_ON(dentry->d_inode);
+	dentry->d_fsdata = (void *)gen;
+}
+
 
 static int ocfs2_dentry_revalidate(struct dentry *dentry,
 				   struct nameidata *nd)
 {
-	struct inode *inode = dentry->d_inode;
+	struct inode *inode;
 	int ret = 0;    /* if all else fails, just return false */
-	struct ocfs2_super *osb = OCFS2_SB(dentry->d_sb);
+	struct ocfs2_super *osb;
+
+	if (nd->flags & LOOKUP_RCU)
+		return -ECHILD;
+
+	inode = dentry->d_inode;
+	osb = OCFS2_SB(dentry->d_sb);
 
 	mlog_entry("(0x%p, '%.*s')\n", dentry,
 		   dentry->d_name.len, dentry->d_name.name);
 
-	/* Never trust a negative dentry - force a new lookup. */
+	/* For a negative dentry -
+	 * check the generation number of the parent and compare with the
+	 * one stored in the inode.
+	 */
 	if (inode == NULL) {
-		mlog(0, "negative dentry: %.*s\n", dentry->d_name.len,
-		     dentry->d_name.name);
-		goto bail;
+		unsigned long gen = (unsigned long) dentry->d_fsdata;
+		unsigned long pgen =
+			OCFS2_I(dentry->d_parent->d_inode)->ip_dir_lock_gen;
+		mlog(0, "negative dentry: %.*s parent gen: %lu "
+			"dentry gen: %lu\n",
+			dentry->d_name.len, dentry->d_name.name, pgen, gen);
+		if (gen != pgen)
+			goto bail;
+		goto valid;
 	}
 
 	BUG_ON(!osb);
@@ -96,6 +119,7 @@ static int ocfs2_dentry_revalidate(struct dentry *dentry,
 		goto bail;
 	}
 
+valid:
 	ret = 1;
 
 bail:
@@ -151,23 +175,25 @@ struct dentry *ocfs2_find_local_alias(struct inode *inode,
 	struct list_head *p;
 	struct dentry *dentry = NULL;
 
-	spin_lock(&dcache_lock);
-
+	spin_lock(&inode->i_lock);
 	list_for_each(p, &inode->i_dentry) {
 		dentry = list_entry(p, struct dentry, d_alias);
 
+		spin_lock(&dentry->d_lock);
 		if (ocfs2_match_dentry(dentry, parent_blkno, skip_unhashed)) {
 			mlog(0, "dentry found: %.*s\n",
 			     dentry->d_name.len, dentry->d_name.name);
 
-			dget_locked(dentry);
+			dget_dlock(dentry);
+			spin_unlock(&dentry->d_lock);
 			break;
 		}
+		spin_unlock(&dentry->d_lock);
 
 		dentry = NULL;
 	}
 
-	spin_unlock(&dcache_lock);
+	spin_unlock(&inode->i_lock);
 
 	return dentry;
 }
@@ -227,6 +253,12 @@ int ocfs2_dentry_attach_lock(struct dentry *dentry,
 	if (!inode)
 		return 0;
 
+	if (!dentry->d_inode && dentry->d_fsdata) {
+		/* Converting a negative dentry to positive
+		   Clear dentry->d_fsdata */
+		dentry->d_fsdata = dl = NULL;
+	}
+
 	if (dl) {
 		mlog_bug_on_msg(dl->dl_parent_blkno != parent_blkno,
 				" \"%.*s\": old parent: %llu, new: %llu\n",