X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?p=pandora-kernel.git;a=blobdiff_plain;f=block%2Felevator.c;h=536be740ba4e6443f4ecb3501b4d45631385e4e6;hp=487dd3da8853971d9bcb77cf6ecf51eb39faedf3;hb=847641d7db15ac3f18b3d4aa05479812abdf397a;hpb=63c422afe3739b68bec0b5c42807d1450c951caf

diff --git a/block/elevator.c b/block/elevator.c
index 487dd3da8853..536be740ba4e 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -50,6 +50,21 @@ static const int elv_hash_shift = 6;
 #define rq_hash_key(rq)		((rq)->sector + (rq)->nr_sectors)
 #define ELV_ON_HASH(rq)		(!hlist_unhashed(&(rq)->hash))
 
+/*
+ * Query io scheduler to see if the current process issuing bio may be
+ * merged with rq.
+ */
+static int elv_iosched_allow_merge(struct request *rq, struct bio *bio)
+{
+	request_queue_t *q = rq->q;
+	elevator_t *e = q->elevator;
+
+	if (e->ops->elevator_allow_merge_fn)
+		return e->ops->elevator_allow_merge_fn(q, rq, bio);
+
+	return 1;
+}
+
 /*
  * can we safely merge with this request?
  */
@@ -65,12 +80,15 @@ inline int elv_rq_merge_ok(struct request *rq, struct bio *bio)
 		return 0;
 
 	/*
-	 * same device and no special stuff set, merge is ok
+	 * must be same device and not a special request
 	 */
-	if (rq->rq_disk == bio->bi_bdev->bd_disk && !rq->special)
-		return 1;
+	if (rq->rq_disk != bio->bi_bdev->bd_disk || rq->special)
+		return 0;
 
-	return 0;
+	if (!elv_iosched_allow_merge(rq, bio))
+		return 0;
+
+	return 1;
 }
 EXPORT_SYMBOL(elv_rq_merge_ok);
 
@@ -93,21 +111,18 @@ static inline int elv_try_merge(struct request *__rq, struct bio *bio)
 
 static struct elevator_type *elevator_find(const char *name)
 {
-	struct elevator_type *e = NULL;
+	struct elevator_type *e;
 	struct list_head *entry;
 
 	list_for_each(entry, &elv_list) {
-		struct elevator_type *__e;
 
-		__e = list_entry(entry, struct elevator_type, list);
+		e = list_entry(entry, struct elevator_type, list);
 
-		if (!strcmp(__e->elevator_name, name)) {
-			e = __e;
-			break;
-		}
+		if (!strcmp(e->elevator_name, name))
+			return e;
 	}
 
-	return e;
+	return NULL;
 }
 
 static void elevator_put(struct elevator_type *e)
@@ -132,7 +147,7 @@ static struct elevator_type *elevator_get(const char *name)
 
 static void *elevator_init_queue(request_queue_t *q, struct elevator_queue *eq)
 {
-	return eq->ops->elevator_init_fn(q, eq);
+	return eq->ops->elevator_init_fn(q);
 }
 
 static void elevator_attach(request_queue_t *q, struct elevator_queue *eq,
@@ -813,7 +828,7 @@ void elv_put_request(request_queue_t *q, struct request *rq)
 	elevator_t *e = q->elevator;
 
 	if (e->ops->elevator_put_req_fn)
-		e->ops->elevator_put_req_fn(q, rq);
+		e->ops->elevator_put_req_fn(rq);
 }
 
 int elv_may_queue(request_queue_t *q, int rw)
@@ -1088,7 +1103,7 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name)
 	struct list_head *entry;
 	int len = 0;
 
-	spin_lock_irq(q->queue_lock);
+	spin_lock_irq(&elv_list_lock);
 	list_for_each(entry, &elv_list) {
 		struct elevator_type *__e;
 
@@ -1098,7 +1113,7 @@ ssize_t elv_iosched_show(request_queue_t *q, char *name)
 		else
 			len += sprintf(name+len, "%s ", __e->elevator_name);
 	}
-	spin_unlock_irq(q->queue_lock);
+	spin_unlock_irq(&elv_list_lock);
 
 	len += sprintf(len+name, "\n");
 	return len;