block: add BLK_MQ_POLL_CLASSIC for hybrid poll and return EINVAL for unexpected value

For q->poll_nsec == -1, means doing classic poll, not hybrid poll.
We introduce a new flag BLK_MQ_POLL_CLASSIC to replace -1, which
may make code much easier to read.

Additionally, since val is an int obtained with kstrtoint(), val can be
a negative value other than -1, so return -EINVAL for that case.

Thanks to Damien Le Moal for some good suggestion.

Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Yufen Yu 2019-03-18 22:44:41 +08:00 committed by Jens Axboe
parent 9496c015ed
commit 29ece8b435
3 changed files with 12 additions and 7 deletions

View file

@ -50,6 +50,9 @@ struct blk_stat_callback;
/* Must be consistent with blk_mq_poll_stats_bkt() */
#define BLK_MQ_POLL_STATS_BKTS 16
/* Doing classic polling */
#define BLK_MQ_POLL_CLASSIC -1
/*
* Maximum number of blkcg policies allowed to be registered concurrently.
* Defined here to simplify include dependency.