block: remove the per-bio/request write hint

With the NVMe support for this gone, there are no consumers of these hints
left, so remove them.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220304175556.407719-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

7 files changed, 0 insertions, 46 deletions

diff --git a/block/bio.c b/block/bio.c
index 151cace2dbe1..3c57b3ba727d 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -257,7 +257,6 @@ void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table,
 	bio->bi_opf = opf;
 	bio->bi_flags = 0;
 	bio->bi_ioprio = 0;
-	bio->bi_write_hint = 0;
 	bio->bi_status = 0;
 	bio->bi_iter.bi_sector = 0;
 	bio->bi_iter.bi_size = 0;
@@ -737,7 +736,6 @@ static int __bio_clone(struct bio *bio, struct bio *bio_src, gfp_t gfp)
 	    bio_flagged(bio_src, BIO_REMAPPED))
 		bio_set_flag(bio, BIO_REMAPPED);
 	bio->bi_ioprio = bio_src->bi_ioprio;
-	bio->bi_write_hint = bio_src->bi_write_hint;
 	bio->bi_iter = bio_src->bi_iter;
 
 	bio_clone_blkg_association(bio, bio_src);
diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index 18c8eafe20b9..7c854584b52b 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -170,7 +170,6 @@ static struct bio *blk_crypto_fallback_clone_bio(struct bio *bio_src)
 		bio_set_flag(bio, BIO_REMAPPED);
 	bio->bi_opf		= bio_src->bi_opf;
 	bio->bi_ioprio		= bio_src->bi_ioprio;
-	bio->bi_write_hint	= bio_src->bi_write_hint;
 	bio->bi_iter.bi_sector	= bio_src->bi_iter.bi_sector;
 	bio->bi_iter.bi_size	= bio_src->bi_iter.bi_size;
 
diff --git a/block/blk-merge.c b/block/blk-merge.c
index f5255991b773..0e871d4e7cb8 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -782,13 +782,6 @@ static struct request *attempt_merge(struct request_queue *q,
 	    !blk_write_same_mergeable(req->bio, next->bio))
 		return NULL;
 
-	/*
-	 * Don't allow merge of different write hints, or for a hint with
-	 * non-hint IO.
-	 */
-	if (req->write_hint != next->write_hint)
-		return NULL;
-
 	if (req->ioprio != next->ioprio)
 		return NULL;
 
@@ -915,13 +908,6 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
 	    !blk_write_same_mergeable(rq->bio, bio))
 		return false;
 
-	/*
-	 * Don't allow merge of different write hints, or for a hint with
-	 * non-hint IO.
-	 */
-	if (rq->write_hint != bio->bi_write_hint)
-		return false;
-
 	if (rq->ioprio != bio_prio(bio))
 		return false;
 
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 3a790eb4995c..c2904c75c160 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -183,35 +183,11 @@ inval:
 	return count;
 }
 
-static int queue_write_hint_show(void *data, struct seq_file *m)
-{
-	struct request_queue *q = data;
-	int i;
-
-	for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
-		seq_printf(m, "hint%d: %llu\n", i, q->write_hints[i]);
-
-	return 0;
-}
-
-static ssize_t queue_write_hint_store(void *data, const char __user *buf,
-				      size_t count, loff_t *ppos)
-{
-	struct request_queue *q = data;
-	int i;
-
-	for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
-		q->write_hints[i] = 0;
-
-	return count;
-}
-
 static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = {
 	{ "poll_stat", 0400, queue_poll_stat_show },
 	{ "requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops },
 	{ "pm_only", 0600, queue_pm_only_show, NULL },
 	{ "state", 0600, queue_state_show, queue_state_write },
-	{ "write_hints", 0600, queue_write_hint_show, queue_write_hint_store },
 	{ "zone_wlock", 0400, queue_zone_wlock_show, NULL },
 	{ },
 };
diff --git a/block/blk-mq.c b/block/blk-mq.c
index f1b067d06ab5..64d5c2edb817 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2406,7 +2406,6 @@ static void blk_mq_bio_to_request(struct request *rq, struct bio *bio,
 		rq->cmd_flags |= REQ_FAILFAST_MASK;
 
 	rq->__sector = bio->bi_iter.bi_sector;
-	rq->write_hint = bio->bi_write_hint;
 	blk_rq_bio_prep(rq, bio, nr_segs);
 
 	/* This can't fail, since GFP_NOIO includes __GFP_DIRECT_RECLAIM. */
diff --git a/block/bounce.c b/block/bounce.c
index 3d50d19cde72..9db1256d57d5 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -169,7 +169,6 @@ static struct bio *bounce_clone_bio(struct bio *bio_src)
 	if (bio_flagged(bio_src, BIO_REMAPPED))
 		bio_set_flag(bio, BIO_REMAPPED);
 	bio->bi_ioprio		= bio_src->bi_ioprio;
-	bio->bi_write_hint	= bio_src->bi_write_hint;
 	bio->bi_iter.bi_sector	= bio_src->bi_iter.bi_sector;
 	bio->bi_iter.bi_size	= bio_src->bi_iter.bi_size;
 
diff --git a/block/fops.c b/block/fops.c
index 7ccc4ff109ce..1c732b72de72 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -83,7 +83,6 @@ static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb,
 		bio_init(&bio, bdev, vecs, nr_pages, dio_bio_write_op(iocb));
 	}
 	bio.bi_iter.bi_sector = pos >> SECTOR_SHIFT;
-	bio.bi_write_hint = iocb->ki_hint;
 	bio.bi_private = current;
 	bio.bi_end_io = blkdev_bio_end_io_simple;
 	bio.bi_ioprio = iocb->ki_ioprio;
@@ -225,7 +224,6 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
 
 	for (;;) {
 		bio->bi_iter.bi_sector = pos >> SECTOR_SHIFT;
-		bio->bi_write_hint = iocb->ki_hint;
 		bio->bi_private = dio;
 		bio->bi_end_io = blkdev_bio_end_io;
 		bio->bi_ioprio = iocb->ki_ioprio;
@@ -327,7 +325,6 @@ static ssize_t __blkdev_direct_IO_async(struct kiocb *iocb,
 	dio->flags = 0;
 	dio->iocb = iocb;
 	bio->bi_iter.bi_sector = pos >> SECTOR_SHIFT;
-	bio->bi_write_hint = iocb->ki_hint;
 	bio->bi_end_io = blkdev_bio_end_io_async;
 	bio->bi_ioprio = iocb->ki_ioprio;