Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:58694 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726112AbeKZNLy (ORCPT ); Mon, 26 Nov 2018 08:11:54 -0500 From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , Omar Sandoval , Sagi Grimberg , Dave Chinner , Kent Overstreet , Mike Snitzer , dm-devel@redhat.com, Alexander Viro , linux-fsdevel@vger.kernel.org, Shaohua Li , linux-raid@vger.kernel.org, David Sterba , linux-btrfs@vger.kernel.org, "Darrick J . Wong" , linux-xfs@vger.kernel.org, Gao Xiang , Christoph Hellwig , linux-ext4@vger.kernel.org, Coly Li , linux-bcache@vger.kernel.org, Boaz Harrosh , Bob Peterson , cluster-devel@redhat.com, Ming Lei Subject: [PATCH V12 08/20] block: introduce bio_for_each_bvec() and rq_for_each_bvec() Date: Mon, 26 Nov 2018 10:17:08 +0800 Message-Id: <20181126021720.19471-9-ming.lei@redhat.com> In-Reply-To: <20181126021720.19471-1-ming.lei@redhat.com> References: <20181126021720.19471-1-ming.lei@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: bio_for_each_bvec() is used for iterating over multi-page bvec for bio split & merge code. rq_for_each_bvec() can be used for drivers which may handle the multi-page bvec directly, so far loop is one perfect use case. Reviewed-by: Omar Sandoval Signed-off-by: Ming Lei --- include/linux/bio.h | 10 ++++++++++ include/linux/blkdev.h | 4 ++++ include/linux/bvec.h | 7 +++++++ 3 files changed, 21 insertions(+) diff --git a/include/linux/bio.h b/include/linux/bio.h index 6a0ff02f4d1c..46fd0e03233b 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -156,6 +156,16 @@ static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, #define bio_for_each_segment(bvl, bio, iter) \ __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) +#define __bio_for_each_bvec(bvl, bio, iter, start) \ + for (iter = (start); \ + (iter).bi_size && \ + ((bvl = bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ + bio_advance_iter((bio), &(iter), (bvl).bv_len)) + +/* iterate over multi-page bvec */ +#define bio_for_each_bvec(bvl, bio, iter) \ + __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) + #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) static inline unsigned bio_segments(struct bio *bio) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 399a7a415609..fa263de3f1d1 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -799,6 +799,10 @@ struct req_iterator { __rq_for_each_bio(_iter.bio, _rq) \ bio_for_each_segment(bvl, _iter.bio, _iter.iter) +#define rq_for_each_bvec(bvl, _rq, _iter) \ + __rq_for_each_bio(_iter.bio, _rq) \ + bio_for_each_bvec(bvl, _iter.bio, _iter.iter) + #define rq_iter_last(bvec, _iter) \ (_iter.bio->bi_next == NULL && \ bio_iter_last(bvec, _iter.iter)) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index babc6316c117..d441486db605 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -65,6 +65,13 @@ struct bvec_iter { #define bvec_iter_page_idx(bvec, iter) \ (bvec_iter_offset((bvec), (iter)) / PAGE_SIZE) +#define bvec_iter_bvec(bvec, iter) \ +((struct bio_vec) { \ + .bv_page = bvec_iter_page((bvec), (iter)), \ + .bv_len = bvec_iter_len((bvec), (iter)), \ + .bv_offset = bvec_iter_offset((bvec), (iter)), \ +}) + /* For building single-page bvec(segment) in flight */ #define segment_iter_offset(bvec, iter) \ (bvec_iter_offset((bvec), (iter)) % PAGE_SIZE) -- 2.9.5