Re: [PATCH] block: Simplify the bio cloning implementation
From: Ming Lei <hidden>
Date: 2018-06-27 01:13:00
On Tue, Jun 26, 2018 at 03:26:24PM -0700, Bart Van Assche wrote:
quoted hunk ↗ jump to hunk
There is no good reason to use different code paths for different request operations. Hence remove the switch/case statement from bio_clone_bioset(). Signed-off-by: Bart Van Assche <redacted> Cc: Christoph Hellwig <hch@lst.de> Cc: Ming Lei <redacted> --- block/bio.c | 15 ++------------- 1 file changed, 2 insertions(+), 13 deletions(-)diff --git a/block/bio.c b/block/bio.c index f7e3d88bd0b6..4c27cc9ea55e 100644 --- a/block/bio.c +++ b/block/bio.c@@ -691,19 +691,8 @@ struct bio *bio_clone_bioset(struct bio *bio_src, gfp_t gfp_mask, bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector; bio->bi_iter.bi_size = bio_src->bi_iter.bi_size; - switch (bio_op(bio)) { - case REQ_OP_DISCARD: - case REQ_OP_SECURE_ERASE: - case REQ_OP_WRITE_ZEROES: - break; - case REQ_OP_WRITE_SAME: - bio->bi_io_vec[bio->bi_vcnt++] = bio_src->bi_io_vec[0]; - break; - default: - bio_for_each_segment(bv, bio_src, iter) - bio->bi_io_vec[bio->bi_vcnt++] = bv; - break; - } + bio_for_each_segment(bv, bio_src, iter) + bio->bi_io_vec[bio->bi_vcnt++] = bv;
The above change may not be correct for WRITE_SAME, since bio_src->bi_iter.bi_size should be the actual bytes to write by drive. Also Christoph has killed bio_clone_bioset() already, and I think that is correct thing to do, see: https://marc.info/?l=linux-block&m=152938432207215&w=2 Thanks, Ming