1 files changed, 28 insertions, 14 deletions

diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index 4a9726aa191f..ed089118c171 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -50,6 +50,7 @@
 #include <linux/freezer.h>
 #include <linux/quota.h>
 #include <linux/dqblk_xfs.h>
+#include <linux/lockref.h>
 
 #include "gfs2.h"
 #include "incore.h"
@@ -148,7 +149,8 @@ static int qd_alloc(struct gfs2_sbd *sdp, struct kqid qid,
         if (!qd)
                 return -ENOMEM;
 
-        atomic_set(&qd->qd_count, 1);
+        qd->qd_lockref.count = 1;
+        spin_lock_init(&qd->qd_lockref.lock);
         qd->qd_id = qid;
         qd->qd_slot = -1;
         INIT_LIST_HEAD(&qd->qd_reclaim);
@@ -180,13 +182,12 @@ static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
                 spin_lock(&qd_lru_lock);
                 list_for_each_entry(qd, &sdp->sd_quota_list, qd_list) {
                         if (qid_eq(qd->qd_id, qid)) {
-                                if (!atomic_read(&qd->qd_count) &&
-                                    !list_empty(&qd->qd_reclaim)) {
+                                lockref_get(&qd->qd_lockref);
+                                if (!list_empty(&qd->qd_reclaim)) {
                                         /* Remove it from reclaim list */
                                         list_del_init(&qd->qd_reclaim);
                                         atomic_dec(&qd_lru_count);
                                 }
-                                atomic_inc(&qd->qd_count);
                                 found = 1;
                                 break;
                         }
@@ -222,18 +223,24 @@ static int qd_get(struct gfs2_sbd *sdp, struct kqid qid,
 static void qd_hold(struct gfs2_quota_data *qd)
 {
         struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd;
-        gfs2_assert(sdp, atomic_read(&qd->qd_count));
-        atomic_inc(&qd->qd_count);
+        gfs2_assert(sdp, !__lockref_is_dead(&qd->qd_lockref));
+        lockref_get(&qd->qd_lockref);
 }
 
 static void qd_put(struct gfs2_quota_data *qd)
 {
-        if (atomic_dec_and_lock(&qd->qd_count, &qd_lru_lock)) {
+        spin_lock(&qd_lru_lock);
+
+        if (!lockref_put_or_lock(&qd->qd_lockref)) {
+
                 /* Add to the reclaim list */
                 list_add_tail(&qd->qd_reclaim, &qd_lru_list);
                 atomic_inc(&qd_lru_count);
-                spin_unlock(&qd_lru_lock);
+
+                spin_unlock(&qd->qd_lockref.lock);
         }
+
+        spin_unlock(&qd_lru_lock);
 }
 
 static int slot_get(struct gfs2_quota_data *qd)
@@ -394,8 +401,8 @@ static int qd_check_sync(struct gfs2_sbd *sdp, struct gfs2_quota_data *qd,
         list_move_tail(&qd->qd_list, &sdp->sd_quota_list);
 
         set_bit(QDF_LOCKED, &qd->qd_flags);
-        gfs2_assert_warn(sdp, atomic_read(&qd->qd_count));
-        atomic_inc(&qd->qd_count);
+        gfs2_assert_warn(sdp, !__lockref_is_dead(&qd->qd_lockref));
+        lockref_get(&qd->qd_lockref);
         qd->qd_change_sync = qd->qd_change;
         gfs2_assert_warn(sdp, qd->qd_slot_count);
         qd->qd_slot_count++;
@@ -1303,15 +1310,22 @@ void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
         while (!list_empty(head)) {
                 qd = list_entry(head->prev, struct gfs2_quota_data, qd_list);
 
-                if (atomic_read(&qd->qd_count) > 1 ||
-                    (atomic_read(&qd->qd_count) &&
-                     !test_bit(QDF_CHANGE, &qd->qd_flags))) {
+                /*
+                 * To be removed in due course... we should be able to
+                 * ensure that all refs to the qd have done by this point
+                 * so that this rather odd test is not required
+                 */
+                spin_lock(&qd->qd_lockref.lock);
+                if (qd->qd_lockref.count > 1 ||
+                    (qd->qd_lockref.count && !test_bit(QDF_CHANGE, &qd->qd_flags))) {
+                        spin_unlock(&qd->qd_lockref.lock);
                         list_move(&qd->qd_list, head);
                         spin_unlock(&qd_lru_lock);
                         schedule();
                         spin_lock(&qd_lru_lock);
                         continue;
                 }
+                spin_unlock(&qd->qd_lockref.lock);
 
                 list_del(&qd->qd_list);
                 /* Also remove if this qd exists in the reclaim list */
@@ -1322,7 +1336,7 @@ void gfs2_quota_cleanup(struct gfs2_sbd *sdp)
                 atomic_dec(&sdp->sd_quota_count);
                 spin_unlock(&qd_lru_lock);
 
-                if (!atomic_read(&qd->qd_count)) {
+                if (!qd->qd_lockref.count) {
                         gfs2_assert_warn(sdp, !qd->qd_change);
                         gfs2_assert_warn(sdp, !qd->qd_slot_count);
                 } else