@@ -956,22 +956,8 @@ blk_qc_t generic_make_request(struct bio *bio)
* yet.
*/
struct bio_list bio_list_on_stack[2];
- blk_mq_req_flags_t flags = 0;
- struct request_queue *q = bio->bi_disk->queue;
blk_qc_t ret = BLK_QC_T_NONE;
- if (bio->bi_opf & REQ_NOWAIT)
- flags = BLK_MQ_REQ_NOWAIT;
- if (bio_flagged(bio, BIO_QUEUE_ENTERED))
- blk_queue_enter_live(q);
- else if (blk_queue_enter(q, flags) < 0) {
- if (!blk_queue_dying(q) && (bio->bi_opf & REQ_NOWAIT))
- bio_wouldblock_error(bio);
- else
- bio_io_error(bio);
- return ret;
- }
-
if (!generic_make_request_checks(bio))
goto out;
@@ -1008,22 +994,11 @@ blk_qc_t generic_make_request(struct bio *bio)
bio_list_init(&bio_list_on_stack[0]);
current->bio_list = bio_list_on_stack;
do {
- bool enter_succeeded = true;
-
- if (unlikely(q != bio->bi_disk->queue)) {
- if (q)
- blk_queue_exit(q);
- q = bio->bi_disk->queue;
- flags = 0;
- if (bio->bi_opf & REQ_NOWAIT)
- flags = BLK_MQ_REQ_NOWAIT;
- if (blk_queue_enter(q, flags) < 0) {
- enter_succeeded = false;
- q = NULL;
- }
- }
+ 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 (enter_succeeded) {
+ if (likely(blk_queue_enter(q, flags) == 0)) {
struct bio_list lower, same;
/* Create a fresh bio_list for all subordinate requests */
@@ -1031,6 +1006,8 @@ blk_qc_t generic_make_request(struct bio *bio)
bio_list_init(&bio_list_on_stack[0]);
ret = q->make_request_fn(q, bio);
+ blk_queue_exit(q);
+
/* sort new bios into those for a lower level
* and those for the same level
*/
@@ -1057,8 +1034,6 @@ blk_qc_t generic_make_request(struct bio *bio)
current->bio_list = NULL; /* deactivate */
out:
- if (q)
- blk_queue_exit(q);
return ret;
}
EXPORT_SYMBOL(generic_make_request);
Now a063057d7c73 ("block: Fix a race between request queue removal and the block cgroup controller") has been reverted, and blkcg_exit_queue() won't be called in blk_cleanup_queue() any more. So don't need to protect generic_make_request_checks() with blk_queue_enter(), then the total mess can be cleaned. 37f9579f4c31 ("blk-mq: Avoid that submitting a bio concurrently with device removal triggers a crash") is reverted. Cc: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bvanassche@acm.org> Signed-off-by: Ming Lei <ming.lei@redhat.com> --- block/blk-core.c | 37 ++++++------------------------------- 1 file changed, 6 insertions(+), 31 deletions(-)