From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-f197.google.com (mail-qt0-f197.google.com [209.85.216.197]) by kanga.kvack.org (Postfix) with ESMTP id B808E6B04A8 for ; Tue, 8 Aug 2017 04:51:22 -0400 (EDT) Received: by mail-qt0-f197.google.com with SMTP id 6so12687517qts.7 for ; Tue, 08 Aug 2017 01:51:22 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id r21si758326qte.305.2017.08.08.01.51.21 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Aug 2017 01:51:21 -0700 (PDT) From: Ming Lei Subject: [PATCH v3 26/49] block: introduce bvec_for_each_sp_bvec() Date: Tue, 8 Aug 2017 16:45:25 +0800 Message-Id: <20170808084548.18963-27-ming.lei@redhat.com> In-Reply-To: <20170808084548.18963-1-ming.lei@redhat.com> References: <20170808084548.18963-1-ming.lei@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei This helper can be used to iterate each singlepage bvec from one multipage bvec. Signed-off-by: Ming Lei --- include/linux/bvec.h | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index c1ec0945451a..23d3abdf057c 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -224,4 +224,18 @@ static inline bool bvec_iter_advance_mp(const struct bio_vec *bv, .bi_bvec_done = 0, \ } +/* + * This helper iterates over the multipage bvec of @mp_bvec and + * returns each singlepage bvec via @sp_bvl. + */ +#define __bvec_for_each_sp_bvec(sp_bvl, mp_bvec, iter, start) \ + for (iter = start, \ + (iter).bi_size = (mp_bvec)->bv_len - (iter).bi_bvec_done; \ + (iter).bi_size && \ + ((sp_bvl = bvec_iter_bvec((mp_bvec), (iter))), 1); \ + bvec_iter_advance((mp_bvec), &(iter), (sp_bvl).bv_len)) + +#define bvec_for_each_sp_bvec(sp_bvl, mp_bvec, iter) \ + __bvec_for_each_sp_bvec(sp_bvl, mp_bvec, iter, BVEC_ITER_ALL_INIT) + #endif /* __LINUX_BVEC_ITER_H */ -- 2.9.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org