From: Jens Axboe Date: Fri, 25 Jan 2008 11:44:44 +0000 (+0100) Subject: __bio_clone: don't calculate hw/phys segment counts X-Git-Tag: v2.6.25-rc1~1171^2~1 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5d84070ee0a433620c57e85dac7f82faaec5fbb3;p=linux-2.6 __bio_clone: don't calculate hw/phys segment counts If the users sets a new ->bi_bdev on the bio after __bio_clone() has returned it, the "segment counts valid" flag still remains even though it may be different with the new target. So don't calculate segment counts in __bio_clone(). Signed-off-by: Jens Axboe --- diff --git a/fs/bio.c b/fs/bio.c index d59ddbf796..242e409dab 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -248,11 +248,13 @@ inline int bio_hw_segments(struct request_queue *q, struct bio *bio) */ void __bio_clone(struct bio *bio, struct bio *bio_src) { - struct request_queue *q = bdev_get_queue(bio_src->bi_bdev); - memcpy(bio->bi_io_vec, bio_src->bi_io_vec, bio_src->bi_max_vecs * sizeof(struct bio_vec)); + /* + * most users will be overriding ->bi_bdev with a new target, + * so we don't set nor calculate new physical/hw segment counts here + */ bio->bi_sector = bio_src->bi_sector; bio->bi_bdev = bio_src->bi_bdev; bio->bi_flags |= 1 << BIO_CLONED; @@ -260,8 +262,6 @@ void __bio_clone(struct bio *bio, struct bio *bio_src) bio->bi_vcnt = bio_src->bi_vcnt; bio->bi_size = bio_src->bi_size; bio->bi_idx = bio_src->bi_idx; - bio_phys_segments(q, bio); - bio_hw_segments(q, bio); } /**