From 34fe7c05400663e01e23cddd1fea68bb7a2b3d29 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 8 Feb 2017 14:46:48 +0100 Subject: block: enumify ELEVATOR_*_MERGE Switch these constants to an enum, and make let the compiler ensure that all callers of blk_try_merge and elv_merge handle all potential values. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 35 +++++++++++++++++------------------ 1 file changed, 17 insertions(+), 18 deletions(-) (limited to 'block/blk-mq-sched.c') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index ee455e7cf9d8..72d0d8361175 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -238,30 +238,29 @@ bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio, struct request **merged_request) { struct request *rq; - int ret; - ret = elv_merge(q, &rq, bio); - if (ret == ELEVATOR_BACK_MERGE) { + switch (elv_merge(q, &rq, bio)) { + case ELEVATOR_BACK_MERGE: if (!blk_mq_sched_allow_merge(q, rq, bio)) return false; - if (bio_attempt_back_merge(q, rq, bio)) { - *merged_request = attempt_back_merge(q, rq); - if (!*merged_request) - elv_merged_request(q, rq, ret); - return true; - } - } else if (ret == ELEVATOR_FRONT_MERGE) { + if (!bio_attempt_back_merge(q, rq, bio)) + return false; + *merged_request = attempt_back_merge(q, rq); + if (!*merged_request) + elv_merged_request(q, rq, ELEVATOR_BACK_MERGE); + return true; + case ELEVATOR_FRONT_MERGE: if (!blk_mq_sched_allow_merge(q, rq, bio)) return false; - if (bio_attempt_front_merge(q, rq, bio)) { - *merged_request = attempt_front_merge(q, rq); - if (!*merged_request) - elv_merged_request(q, rq, ret); - return true; - } + if (!bio_attempt_front_merge(q, rq, bio)) + return false; + *merged_request = attempt_front_merge(q, rq); + if (!*merged_request) + elv_merged_request(q, rq, ELEVATOR_FRONT_MERGE); + return true; + default: + return false; } - - return false; } EXPORT_SYMBOL_GPL(blk_mq_sched_try_merge); -- cgit