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block: add a bio_queue_enter helper

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Add a little helper that passes the right nowait flag to blk_queue_enter
based on the bio flag, and terminates the bio with the right error code
if entering the queue fails.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2020-04-28 13:27:56 +02:00 committed by Jens Axboe
parent 0376e9efe1
commit accea322f5
1 changed files with 24 additions and 26 deletions
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50
block/blk-core.c
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@ -440,6 +440,23 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags)
}
}
static inline int bio_queue_enter(struct bio *bio)
{
struct request_queue *q = bio->bi_disk->queue;
bool nowait = bio->bi_opf & REQ_NOWAIT;
int ret;
ret = blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0);
if (unlikely(ret)) {
if (nowait && !blk_queue_dying(q))
bio_wouldblock_error(bio);
else
bio_io_error(bio);
}
return ret;
}
void blk_queue_exit(struct request_queue *q)
{
percpu_ref_put(&q->q_usage_counter);
@ -1049,10 +1066,8 @@ blk_qc_t generic_make_request(struct bio *bio)
current->bio_list = bio_list_on_stack;
do {
struct request_queue *q = bio->bi_disk->queue;
blk_mq_req_flags_t flags = bio->bi_opf & REQ_NOWAIT ?
BLK_MQ_REQ_NOWAIT : 0;
if (likely(blk_queue_enter(q, flags) == 0)) {
if (likely(bio_queue_enter(bio) == 0)) {
struct bio_list lower, same;
/* Create a fresh bio_list for all subordinate requests */
@ -1079,12 +1094,6 @@ blk_qc_t generic_make_request(struct bio *bio)
bio_list_merge(&bio_list_on_stack[0], &lower);
bio_list_merge(&bio_list_on_stack[0], &same);
bio_list_merge(&bio_list_on_stack[0], &bio_list_on_stack[1]);
} else {
if (unlikely(!blk_queue_dying(q) &&
(bio->bi_opf & REQ_NOWAIT)))
bio_wouldblock_error(bio);
else
bio_io_error(bio);
}
bio = bio_list_pop(&bio_list_on_stack[0]);
} while (bio);
@ -1106,30 +1115,19 @@ EXPORT_SYMBOL(generic_make_request);
blk_qc_t direct_make_request(struct bio *bio)
{
struct request_queue *q = bio->bi_disk->queue;
bool nowait = bio->bi_opf & REQ_NOWAIT;
blk_qc_t ret;
if (WARN_ON_ONCE(q->make_request_fn))
goto io_error;
if (WARN_ON_ONCE(q->make_request_fn)) {
bio_io_error(bio);
return BLK_QC_T_NONE;
}
if (!generic_make_request_checks(bio))
return BLK_QC_T_NONE;
if (unlikely(blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0))) {
if (nowait && !blk_queue_dying(q))
goto would_block;
goto io_error;
}
if (unlikely(bio_queue_enter(bio)))
return BLK_QC_T_NONE;
ret = blk_mq_make_request(q, bio);
blk_queue_exit(q);
return ret;
would_block:
bio_wouldblock_error(bio);
return BLK_QC_T_NONE;
io_error:
bio_io_error(bio);
return BLK_QC_T_NONE;
}
EXPORT_SYMBOL_GPL(direct_make_request);