X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fxfs%2Fxfs_mru_cache.c;h=afee7eb243234824a44a8ad9b91fc23200fdc6ea;hb=76a67ec6fb79ff3570dcb5342142c16098299911;hp=dc64630e870ea324bf28dab9dcebd20500bb20b8;hpb=ba74d0cba51dcaa99e4dc2e4fb62e6e13abbf703;p=safe%2Fjmp%2Flinux-2.6

diff --git a/fs/xfs/xfs_mru_cache.c b/fs/xfs/xfs_mru_cache.c
index dc64630..afee7eb 100644
--- a/fs/xfs/xfs_mru_cache.c
+++ b/fs/xfs/xfs_mru_cache.c
@@ -225,10 +225,14 @@ _xfs_mru_cache_list_insert(
  * list need to be deleted.  For each element this involves removing it from the
  * data store, removing it from the reap list, calling the client's free
  * function and deleting the element from the element zone.
+ *
+ * We get called holding the mru->lock, which we drop and then reacquire.
+ * Sparse need special help with this to tell it we know what we are doing.
  */
 STATIC void
 _xfs_mru_cache_clear_reap_list(
-	xfs_mru_cache_t		*mru)
+	xfs_mru_cache_t		*mru) __releases(mru->lock) __acquires(mru->lock)
+
 {
 	xfs_mru_cache_elem_t	*elem, *next;
 	struct list_head	tmp;
@@ -303,15 +307,18 @@ xfs_mru_cache_init(void)
 	xfs_mru_elem_zone = kmem_zone_init(sizeof(xfs_mru_cache_elem_t),
 	                                 "xfs_mru_cache_elem");
 	if (!xfs_mru_elem_zone)
-		return ENOMEM;
+		goto out;
 
 	xfs_mru_reap_wq = create_singlethread_workqueue("xfs_mru_cache");
-	if (!xfs_mru_reap_wq) {
-		kmem_zone_destroy(xfs_mru_elem_zone);
-		return ENOMEM;
-	}
+	if (!xfs_mru_reap_wq)
+		goto out_destroy_mru_elem_zone;
 
 	return 0;
+
+ out_destroy_mru_elem_zone:
+	kmem_zone_destroy(xfs_mru_elem_zone);
+ out:
+	return -ENOMEM;
 }
 
 void
@@ -368,7 +375,7 @@ xfs_mru_cache_create(
 	 */
 	INIT_RADIX_TREE(&mru->store, GFP_ATOMIC);
 	INIT_LIST_HEAD(&mru->reap_list);
-	spinlock_init(&mru->lock, "xfs_mru_cache");
+	spin_lock_init(&mru->lock);
 	INIT_DELAYED_WORK(&mru->work, _xfs_mru_cache_reap);
 
 	mru->grp_time  = grp_time;
@@ -378,9 +385,9 @@ xfs_mru_cache_create(
 
 exit:
 	if (err && mru && mru->lists)
-		kmem_free(mru->lists, mru->grp_count * sizeof(*mru->lists));
+		kmem_free(mru->lists);
 	if (err && mru)
-		kmem_free(mru, sizeof(*mru));
+		kmem_free(mru);
 
 	return err;
 }
@@ -420,8 +427,8 @@ xfs_mru_cache_destroy(
 
 	xfs_mru_cache_flush(mru);
 
-	kmem_free(mru->lists, mru->grp_count * sizeof(*mru->lists));
-	kmem_free(mru, sizeof(*mru));
+	kmem_free(mru->lists);
+	kmem_free(mru);
 }
 
 /*
@@ -528,6 +535,10 @@ xfs_mru_cache_delete(
  *
  * If the element isn't found, this function returns NULL and the spinlock is
  * released.  xfs_mru_cache_done() should NOT be called when this occurs.
+ *
+ * Because sparse isn't smart enough to know about conditional lock return
+ * status, we need to help it get it right by annotating the path that does
+ * not release the lock.
  */
 void *
 xfs_mru_cache_lookup(
@@ -545,8 +556,8 @@ xfs_mru_cache_lookup(
 	if (elem) {
 		list_del(&elem->list_node);
 		_xfs_mru_cache_list_insert(mru, elem);
-	}
-	else
+		__release(mru_lock); /* help sparse not be stupid */
+	} else
 		spin_unlock(&mru->lock);
 
 	return elem ? elem->value : NULL;
@@ -575,6 +586,8 @@ xfs_mru_cache_peek(
 	elem = radix_tree_lookup(&mru->store, key);
 	if (!elem)
 		spin_unlock(&mru->lock);
+	else
+		__release(mru_lock); /* help sparse not be stupid */
 
 	return elem ? elem->value : NULL;
 }
@@ -586,7 +599,7 @@ xfs_mru_cache_peek(
  */
 void
 xfs_mru_cache_done(
-	xfs_mru_cache_t	*mru)
+	xfs_mru_cache_t	*mru) __releases(mru->lock)
 {
 	spin_unlock(&mru->lock);
 }