Signed-off-by: Li kunyu <likunyu10@163.com>
---
v2: Fix the use of 'split' in the 'bio_set_flag' function to 'bio'

 block/bio.c               |  2 ++
 block/blk-iolatency.c     | 34 ++++++++++++++++++++++++++++++++++
 block/blk-merge.c         |  7 ++++++-
 block/blk-rq-qos.h        | 11 +++++++++++
 include/linux/blk_types.h |  2 ++
 5 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/block/bio.c b/block/bio.c
index b8972dba68a0..7740701afc7f 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1733,6 +1733,8 @@ static inline bool bio_remaining_done(struct bio *bio)
 		return true;
 	}
 
+	rq_qos_done_split_bio(bio);
+
 	return false;
 }
 
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index 53e8dd2dfa8a..ba5870bf14c5 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -632,6 +632,39 @@ static void blkcg_iolatency_done_bio(struct rq_qos *rqos, struct bio *bio)
 	}
 }
 
+static void blkcg_iolatency_done_split_bio(struct rq_qos *rqos, struct bio *bio)
+{
+	struct blkcg_gq *blkg;
+	struct rq_wait *rqw;
+	struct iolatency_grp *iolat;
+	int inflight = 0;
+
+	blkg = bio->bi_blkg;
+	if (!blkg || !bio_flagged(bio, BIO_QOS_CHAIN_CHILD))
+		return;
+
+	iolat = blkg_to_lat(bio->bi_blkg);
+	if (!iolat)
+		return;
+
+	if (!iolat->blkiolat->enabled)
+		return;
+
+	while (blkg && blkg->parent) {
+		iolat = blkg_to_lat(blkg);
+		if (!iolat) {
+			blkg = blkg->parent;
+			continue;
+		}
+		rqw = &iolat->rq_wait;
+
+		inflight = atomic_dec_return(&rqw->inflight);
+		WARN_ON_ONCE(inflight < 0);
+
+		blkg = blkg->parent;
+	}
+}
+
 static void blkcg_iolatency_exit(struct rq_qos *rqos)
 {
 	struct blk_iolatency *blkiolat = BLKIOLATENCY(rqos);
@@ -645,6 +678,7 @@ static void blkcg_iolatency_exit(struct rq_qos *rqos)
 static const struct rq_qos_ops blkcg_iolatency_ops = {
 	.throttle = blkcg_iolatency_throttle,
 	.done_bio = blkcg_iolatency_done_bio,
+	.done_split_bio = blkcg_iolatency_done_split_bio,
 	.exit = blkcg_iolatency_exit,
 };
 
diff --git a/block/blk-merge.c b/block/blk-merge.c
index fcf09325b22e..84373e3e1bbe 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -151,8 +151,13 @@ static struct bio *bio_submit_split(struct bio *bio, int split_sectors)
 	if (split_sectors) {
 		bio = bio_submit_split_bioset(bio, split_sectors,
 				&bio->bi_bdev->bd_disk->bio_split);
-		if (bio)
+		if (bio) {
 			bio->bi_opf |= REQ_NOMERGE;
+			/* Fix the issue where the inflight statistics
+			 * of the chained bio in the QoS are incorrect.
+			 */
+			bio_set_flag(bio, BIO_QOS_CHAIN_CHILD);
+		}
 	}
 
 	return bio;
diff --git a/block/blk-rq-qos.h b/block/blk-rq-qos.h
index a747a504fe42..496a27b9d412 100644
--- a/block/blk-rq-qos.h
+++ b/block/blk-rq-qos.h
@@ -45,6 +45,7 @@ struct rq_qos_ops {
 	void (*cleanup)(struct rq_qos *, struct bio *);
 	void (*queue_depth_changed)(struct rq_qos *);
 	void (*exit)(struct rq_qos *);
+	void (*done_split_bio)(struct rq_qos *, struct bio *);
 	const struct blk_mq_debugfs_attr *debugfs_attrs;
 };
 
@@ -108,6 +109,7 @@ void __rq_qos_throttle(struct rq_qos *rqos, struct bio *bio);
 void __rq_qos_track(struct rq_qos *rqos, struct request *rq, struct bio *bio);
 void __rq_qos_merge(struct rq_qos *rqos, struct request *rq, struct bio *bio);
 void __rq_qos_done_bio(struct rq_qos *rqos, struct bio *bio);
+void __rq_qos_done_split_bio(struct rq_qos *rqos, struct bio *bio);
 void __rq_qos_queue_depth_changed(struct rq_qos *rqos);
 
 static inline void rq_qos_cleanup(struct request_queue *q, struct bio *bio)
@@ -157,6 +159,15 @@ static inline void rq_qos_done_bio(struct bio *bio)
 		__rq_qos_done_bio(q->rq_qos, bio);
 }
 
+static inline void rq_qos_done_split_bio(struct bio *bio)
+{
+	if (bio->bi_bdev && bio_flagged(bio, BIO_QOS_CHAIN_CHILD)) {
+		struct request_queue *q = bdev_get_queue(bio->bi_bdev);
+		if (q->rq_qos)
+			__rq_qos_done_split_bio(q->rq_qos, bio);
+	}
+}
+
 static inline void rq_qos_throttle(struct request_queue *q, struct bio *bio)
 {
 	if (test_bit(QUEUE_FLAG_QOS_ENABLED, &q->queue_flags) && q->rq_qos) {
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 8808ee76e73c..63fee89ecc14 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -322,6 +322,8 @@ enum {
 	BIO_REMAPPED,
 	BIO_ZONE_WRITE_PLUGGING, /* bio handled through zone write plugging */
 	BIO_EMULATES_ZONE_APPEND, /* bio emulates a zone append operation */
+	BIO_QOS_CHAIN_CHILD,    /* chained bio child, used for segmenting out
+				* the bio */
 	BIO_FLAG_LAST
 };
 
-- 
2.47.3