X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=block%2Felevator.c;h=8cd5775acd7a2d4c1111acb0f823a57a46819dc0;hb=64b7d96167977850f4a24e52dd0a76b03c6542cf;hp=446aea2a3cfbd17e6ff8d15fc0b069785d196e7f;hpb=0b776eb5426752d4e53354ac89e3710d857e09a7;p=linux-2.6

diff --git a/block/elevator.c b/block/elevator.c
index 446aea2a3c..8cd5775acd 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -185,9 +185,7 @@ static elevator_t *elevator_alloc(struct request_queue *q,
 
 	eq->ops = &e->ops;
 	eq->elevator_type = e;
-	kobject_init(&eq->kobj);
-	kobject_set_name(&eq->kobj, "%s", "iosched");
-	eq->kobj.ktype = &elv_ktype;
+	kobject_init(&eq->kobj, &elv_ktype);
 	mutex_init(&eq->sysfs_lock);
 
 	eq->hash = kmalloc_node(sizeof(struct hlist_head) * ELV_HASH_ENTRIES,
@@ -743,7 +741,21 @@ struct request *elv_next_request(struct request_queue *q)
 			q->boundary_rq = NULL;
 		}
 
-		if ((rq->cmd_flags & REQ_DONTPREP) || !q->prep_rq_fn)
+		if (rq->cmd_flags & REQ_DONTPREP)
+			break;
+
+		if (q->dma_drain_size && rq->data_len) {
+			/*
+			 * make sure space for the drain appears we
+			 * know we can do this because max_hw_segments
+			 * has been adjusted to be one fewer than the
+			 * device can handle
+			 */
+			rq->nr_phys_segments++;
+			rq->nr_hw_segments++;
+		}
+
+		if (!q->prep_rq_fn)
 			break;
 
 		ret = q->prep_rq_fn(q, rq);
@@ -756,6 +768,16 @@ struct request *elv_next_request(struct request_queue *q)
 			 * avoid resource deadlock.  REQ_STARTED will
 			 * prevent other fs requests from passing this one.
 			 */
+			if (q->dma_drain_size && rq->data_len &&
+			    !(rq->cmd_flags & REQ_DONTPREP)) {
+				/*
+				 * remove the space for the drain we added
+				 * so that we don't add it again
+				 */
+				--rq->nr_phys_segments;
+				--rq->nr_hw_segments;
+			}
+
 			rq = NULL;
 			break;
 		} else if (ret == BLKPREP_KILL) {
@@ -931,9 +953,7 @@ int elv_register_queue(struct request_queue *q)
 	elevator_t *e = q->elevator;
 	int error;
 
-	e->kobj.parent = &q->kobj;
-
-	error = kobject_add(&e->kobj);
+	error = kobject_add(&e->kobj, &q->kobj, "%s", "iosched");
 	if (!error) {
 		struct elv_fs_entry *attr = e->elevator_type->elevator_attrs;
 		if (attr) {
@@ -960,7 +980,7 @@ void elv_unregister_queue(struct request_queue *q)
 		__elv_unregister_queue(q->elevator);
 }
 
-int elv_register(struct elevator_type *e)
+void elv_register(struct elevator_type *e)
 {
 	char *def = "";
 
@@ -975,7 +995,6 @@ int elv_register(struct elevator_type *e)
 				def = " (default)";
 
 	printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name, def);
-	return 0;
 }
 EXPORT_SYMBOL_GPL(elv_register);