--- linux-3.0/fs/quota/dquot.c.orig	2013-07-18 09:46:28.000000000 -0400
+++ linux-3.0/fs/quota/dquot.c	2013-07-18 09:49:20.000000000 -0400
@@ -1342,7 +1342,7 @@
 static void __dquot_initialize(struct inode *inode, int type)
 {
 	unsigned int id = 0;
-	int cnt;
+	int cnt, ret = 0, dq_get = 0;
 	struct dquot *got[MAXQUOTAS];
 	struct super_block *sb = inode->i_sb;
 	qsize_t rsv;
@@ -1352,7 +1352,14 @@
 	if (!dquot_active(inode))
 		return;
 
-	/* First get references to structures we might need. */
+	/* In most case, the i_dquot should have been initialized, except
+	 * the newly allocated one. We'd always try to skip the dqget() and
+	 * dqput() calls to avoid unnecessary global lock contention. */
+	if (!(inode->i_state & I_NEW))
+		goto init_idquot;
+
+get_dquots:
+	dq_get = 1;
 	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 		got[cnt] = NULL;
 		if (type != -1 && cnt != type)
@@ -1367,7 +1374,7 @@
 		}
 		got[cnt] = dqget(sb, id, cnt);
 	}
-
+init_idquot:
 	spin_lock(&inode->i_lock);
 	if (IS_NOQUOTA(inode))
 		goto out_err;
@@ -1381,6 +1388,10 @@
 		if (!got[cnt])
 			continue;
 		if (!inode->i_dquot[cnt]) {
+			if (dq_get == 0) {
+				spin_unlock(&inode->i_lock);
+				goto get_dquots;
+			}
 			inode->i_dquot[cnt] = got[cnt];
 			got[cnt] = NULL;
 			/*
@@ -1388,7 +1399,7 @@
 			 * did a write before quota was turned on
 			 */
 			rsv = inode_get_rsv_space(inode);
-			if (unlikely(rsv)) {
+			if (unlikely(rsv) && likely(inode->i_dquot[cnt])) {
 				spin_lock(&dq_data_lock);
 				dquot_resv_space(inode->i_dquot[cnt], rsv);
 				spin_unlock(&dq_data_lock);