Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec/ocfs2:
  ocfs2: ocfs2_write_begin_nolock() should handle len=0
  ocfs2: invalidate dentry if its dentry_lock isn't initialized.

fs/ocfs2/aops.c

@@ -1747,8 +1747,8 @@ int ocfs2_write_begin_nolock(struct address_space *mapping,
 	 * we know zeros will only be needed in the first and/or last cluster.
 	 */
 	if (clusters_to_alloc || extents_to_split ||
-	    wc->w_desc[0].c_needs_zero ||
-	    wc->w_desc[wc->w_clen - 1].c_needs_zero)
+	    (wc->w_clen && (wc->w_desc[0].c_needs_zero ||
+			    wc->w_desc[wc->w_clen - 1].c_needs_zero)))
 		cluster_of_pages = 1;
 	else
 		cluster_of_pages = 0;

fs/ocfs2/dcache.c

@@ -85,6 +85,17 @@ static int ocfs2_dentry_revalidate(struct dentry *dentry,
 		goto bail;
 	}
 
+	/*
+	 * If the last lookup failed to create dentry lock, let us
+	 * redo it.
+	 */
+	if (!dentry->d_fsdata) {
+		mlog(0, "Inode %llu doesn't have dentry lock, "
+		     "returning false\n",
+		     (unsigned long long)OCFS2_I(inode)->ip_blkno);
+		goto bail;
+	}
+
 	ret = 1;
 
 bail: