From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03B6FC43441 for ; Thu, 15 Nov 2018 08:56:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CAD48223CB for ; Thu, 15 Nov 2018 08:56:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CAD48223CB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388067AbeKOTCx (ORCPT ); Thu, 15 Nov 2018 14:02:53 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49292 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728699AbeKOTCw (ORCPT ); Thu, 15 Nov 2018 14:02:52 -0500 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0C7F23099F9E; Thu, 15 Nov 2018 08:55:58 +0000 (UTC) Received: from localhost (ovpn-8-23.pek2.redhat.com [10.72.8.23]) by smtp.corp.redhat.com (Postfix) with ESMTP id EC3145D9D1; Thu, 15 Nov 2018 08:55:48 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ming Lei , Dave Chinner , Kent Overstreet , Mike Snitzer , dm-devel@redhat.com, Alexander Viro , linux-fsdevel@vger.kernel.org, Shaohua Li , linux-raid@vger.kernel.org, linux-erofs@lists.ozlabs.org, David Sterba , linux-btrfs@vger.kernel.org, "Darrick J . Wong" , linux-xfs@vger.kernel.org, Gao Xiang , Christoph Hellwig , Theodore Ts'o , linux-ext4@vger.kernel.org, Coly Li , linux-bcache@vger.kernel.org, Boaz Harrosh , Bob Peterson , cluster-devel@redhat.com Subject: [PATCH V10 10/19] block: loop: pass multi-page bvec to iov_iter Date: Thu, 15 Nov 2018 16:52:57 +0800 Message-Id: <20181115085306.9910-11-ming.lei@redhat.com> In-Reply-To: <20181115085306.9910-1-ming.lei@redhat.com> References: <20181115085306.9910-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Thu, 15 Nov 2018 08:55:58 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org iov_iter is implemented with bvec itererator, so it is safe to pass multipage bvec to it, and this way is much more efficient than passing one page in each bvec. Cc: Dave Chinner Cc: Kent Overstreet Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Alexander Viro Cc: linux-fsdevel@vger.kernel.org Cc: Shaohua Li Cc: linux-raid@vger.kernel.org Cc: linux-erofs@lists.ozlabs.org Cc: David Sterba Cc: linux-btrfs@vger.kernel.org Cc: Darrick J. Wong Cc: linux-xfs@vger.kernel.org Cc: Gao Xiang Cc: Christoph Hellwig Cc: Theodore Ts'o Cc: linux-ext4@vger.kernel.org Cc: Coly Li Cc: linux-bcache@vger.kernel.org Cc: Boaz Harrosh Cc: Bob Peterson Cc: cluster-devel@redhat.com Signed-off-by: Ming Lei --- drivers/block/loop.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index bf6bc35aaf88..a3fd418ec637 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -515,16 +515,16 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, struct bio *bio = rq->bio; struct file *file = lo->lo_backing_file; unsigned int offset; - int segments = 0; + int nr_bvec = 0; int ret; if (rq->bio != rq->biotail) { - struct req_iterator iter; + struct bvec_iter iter; struct bio_vec tmp; __rq_for_each_bio(bio, rq) - segments += bio_segments(bio); - bvec = kmalloc_array(segments, sizeof(struct bio_vec), + nr_bvec += bio_bvecs(bio); + bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec), GFP_NOIO); if (!bvec) return -EIO; @@ -533,13 +533,14 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, /* * The bios of the request may be started from the middle of * the 'bvec' because of bio splitting, so we can't directly - * copy bio->bi_iov_vec to new bvec. The rq_for_each_segment + * copy bio->bi_iov_vec to new bvec. The bio_for_each_bvec * API will take care of all details for us. */ - rq_for_each_segment(tmp, rq, iter) { - *bvec = tmp; - bvec++; - } + __rq_for_each_bio(bio, rq) + bio_for_each_bvec(tmp, bio, iter) { + *bvec = tmp; + bvec++; + } bvec = cmd->bvec; offset = 0; } else { @@ -550,11 +551,11 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, */ offset = bio->bi_iter.bi_bvec_done; bvec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); - segments = bio_segments(bio); + nr_bvec = bio_bvecs(bio); } atomic_set(&cmd->ref, 2); - iov_iter_bvec(&iter, rw, bvec, segments, blk_rq_bytes(rq)); + iov_iter_bvec(&iter, rw, bvec, nr_bvec, blk_rq_bytes(rq)); iter.iov_offset = offset; cmd->iocb.ki_pos = pos; -- 2.9.5