Revert "blk-mq: put driver tag when this request is completed"

This reverts commits the following commits:

	37f4a24c2469a10a4c16c641671bd766e276cf9f
	723bf178f158abd1ce6069cb049581b3cb003aab
	36a3df5a4574d5ddf59804fcd0c4e9654c514d9a

The last one is the culprit, but we have to go a bit deeper to get this
to revert cleanly. There's been a report that this breaks some MMC
setups [1], and also causes an issue with swap [2]. Until this can be
figured out, revert the offending commits.

[1] https://lore.kernel.org/linux-block/57fb09b1-54ba-f3aa-f82c-d709b0e6b281@samsung.com/
[2] https://lore.kernel.org/linux-block/20200702043721.GA1087@lca.pw/

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 20 insertions, 0 deletions

diff --git a/block/blk-mq.h b/block/blk-mq.h
index 3661e821d460..863a2f3346d4 100644
--- a/block/blk-mq.h
+++ b/block/blk-mq.h
@@ -193,6 +193,26 @@ static inline bool blk_mq_get_dispatch_budget(struct request_queue *q)
 	return true;
 }
 
+static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
+					   struct request *rq)
+{
+	blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
+	rq->tag = BLK_MQ_NO_TAG;
+
+	if (rq->rq_flags & RQF_MQ_INFLIGHT) {
+		rq->rq_flags &= ~RQF_MQ_INFLIGHT;
+		atomic_dec(&hctx->nr_active);
+	}
+}
+
+static inline void blk_mq_put_driver_tag(struct request *rq)
+{
+	if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
+		return;
+
+	__blk_mq_put_driver_tag(rq->mq_hctx, rq);
+}
+
 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
 {
 	int cpu;