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>
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 5968591..4223270 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -360,8 +360,8 @@ static ssize_t queue_poll_delay_show(struct request_queue *q, char *page)
{
int val;
- if (q->poll_nsec == -1)
- val = -1;
+ if (q->poll_nsec == BLK_MQ_POLL_CLASSIC)
+ val = BLK_MQ_POLL_CLASSIC;
else
val = q->poll_nsec / 1000;
@@ -380,10 +380,12 @@ static ssize_t queue_poll_delay_store(struct request_queue *q, const char *page,
if (err < 0)
return err;
- if (val == -1)
- q->poll_nsec = -1;
- else
+ if (val == BLK_MQ_POLL_CLASSIC)
+ q->poll_nsec = BLK_MQ_POLL_CLASSIC;
+ else if (val >= 0)
q->poll_nsec = val * 1000;
+ else
+ return -EINVAL;
return count;
}