block: remove the bi_phys_segments field in struct bio

We only need the number of segments in the blk-mq submission path.
Remove the field from struct bio, and return it from a variant of
blk_queue_split instead of that it can passed as an argument to
those functions that need the value.

This also means we stop recounting segments except for cloning
and partial segments.

To keep the number of arguments in this how path down remove
pointless struct request_queue arguments from any of the functions
that had it and grew a nr_segs argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 1 insertions, 14 deletions

diff --git a/block/bio.c b/block/bio.c
index 4bcdcd3f63f4..ad9c3aa9bf7d 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -558,14 +558,6 @@ void bio_put(struct bio *bio)
 }
 EXPORT_SYMBOL(bio_put);
 
-int bio_phys_segments(struct request_queue *q, struct bio *bio)
-{
-	if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
-		blk_recount_segments(q, bio);
-
-	return bio->bi_phys_segments;
-}
-
 /**
  * 	__bio_clone_fast - clone a bio that shares the original bio's biovec
  * 	@bio: destination bio
@@ -739,7 +731,7 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
 	if (bio_full(bio))
 		return 0;
 
-	if (bio->bi_phys_segments >= queue_max_segments(q))
+	if (bio->bi_vcnt >= queue_max_segments(q))
 		return 0;
 
 	bvec = &bio->bi_io_vec[bio->bi_vcnt];
@@ -749,8 +741,6 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio,
 	bio->bi_vcnt++;
  done:
 	bio->bi_iter.bi_size += len;
-	bio->bi_phys_segments = bio->bi_vcnt;
-	bio_set_flag(bio, BIO_SEG_VALID);
 	return len;
 }
 
@@ -1909,10 +1899,7 @@ void bio_trim(struct bio *bio, int offset, int size)
 	if (offset == 0 && size == bio->bi_iter.bi_size)
 		return;
 
-	bio_clear_flag(bio, BIO_SEG_VALID);
-
 	bio_advance(bio, offset << 9);
-
 	bio->bi_iter.bi_size = size;
 
 	if (bio_integrity(bio))