diff options
Diffstat (limited to 'block/elevator.c')
| -rw-r--r-- | block/elevator.c | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/block/elevator.c b/block/elevator.c index 9ad5ccc4c5ee..923a9139106c 100644 --- a/block/elevator.c +++ b/block/elevator.c @@ -154,7 +154,7 @@ static struct elevator_type *elevator_get(const char *name) spin_unlock(&elv_list_lock); - sprintf(elv, "%s-iosched", name); + snprintf(elv, sizeof(elv), "%s-iosched", name); request_module("%s", elv); spin_lock(&elv_list_lock); @@ -242,9 +242,11 @@ int elevator_init(struct request_queue *q, char *name) { struct elevator_type *e = NULL; struct elevator_queue *eq; - int ret = 0; void *data; + if (unlikely(q->elevator)) + return 0; + INIT_LIST_HEAD(&q->queue_head); q->last_merge = NULL; q->end_sector = 0; @@ -284,7 +286,7 @@ int elevator_init(struct request_queue *q, char *name) } elevator_attach(q, eq, data); - return ret; + return 0; } EXPORT_SYMBOL(elevator_init); @@ -474,6 +476,15 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio) int ret; /* + * Levels of merges: + * nomerges: No merges at all attempted + * noxmerges: Only simple one-hit cache try + * merges: All merge tries attempted + */ + if (blk_queue_nomerges(q)) + return ELEVATOR_NO_MERGE; + + /* * First try one-hit cache. */ if (q->last_merge) { @@ -484,7 +495,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio) } } - if (blk_queue_nomerges(q)) + if (blk_queue_noxmerges(q)) return ELEVATOR_NO_MERGE; /* @@ -530,6 +541,15 @@ void elv_merge_requests(struct request_queue *q, struct request *rq, q->last_merge = rq; } +void elv_bio_merged(struct request_queue *q, struct request *rq, + struct bio *bio) +{ + struct elevator_queue *e = q->elevator; + + if (e->ops->elevator_bio_merged_fn) + e->ops->elevator_bio_merged_fn(q, rq, bio); +} + void elv_requeue_request(struct request_queue *q, struct request *rq) { /* @@ -883,7 +903,7 @@ elv_attr_store(struct kobject *kobj, struct attribute *attr, return error; } -static struct sysfs_ops elv_sysfs_ops = { +static const struct sysfs_ops elv_sysfs_ops = { .show = elv_attr_show, .store = elv_attr_store, }; @@ -912,6 +932,7 @@ int elv_register_queue(struct request_queue *q) } return error; } +EXPORT_SYMBOL(elv_register_queue); static void __elv_unregister_queue(struct elevator_queue *e) { @@ -924,6 +945,7 @@ void elv_unregister_queue(struct request_queue *q) if (q) __elv_unregister_queue(q->elevator); } +EXPORT_SYMBOL(elv_unregister_queue); void elv_register(struct elevator_type *e) { @@ -1077,7 +1099,7 @@ ssize_t elv_iosched_show(struct request_queue *q, char *name) struct elevator_type *__e; int len = 0; - if (!q->elevator) + if (!q->elevator || !blk_queue_stackable(q)) return sprintf(name, "none\n"); elv = e->elevator_type; |