From patchwork Wed Nov 23 20:57:36 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 628163 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 495BFC433FE for ; Wed, 23 Nov 2022 20:58:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235823AbiKWU63 (ORCPT ); Wed, 23 Nov 2022 15:58:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52566 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239268AbiKWU6M (ORCPT ); Wed, 23 Nov 2022 15:58:12 -0500 Received: from mail-pj1-f47.google.com (mail-pj1-f47.google.com [209.85.216.47]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 89AACF02D; Wed, 23 Nov 2022 12:58:11 -0800 (PST) Received: by mail-pj1-f47.google.com with SMTP id x13-20020a17090a46cd00b00218f611b6e9so1276941pjg.1; Wed, 23 Nov 2022 12:58:11 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=pLbbN/1qbe+HxyJXe7G2OJd9lUGhOuHPJTNebNcpj5I=; b=0Ew7oUNov/C4LPwoR9i4zEM32v5rTM+Kb3ZOMqune2amhErCLPYrRunEBFQpD/qJA2 91cEprlK1FvCzPRWihL65fLWvzuBWr/CpmtDOpDbPWf4WSfUpq/GST+7FhB4OT7LTUdS mhhv2ikBmzN4KBei14EjjyAQrDDGjhmwh1/9NhAKPjYuptYgo+elRGQcjd1HB3cvx8X7 t+MDc5De5WIihrk4Ylf3u+EC+AeohBau3fv5HX4mra43l/zcuiXeWtTEX4wEjc2TwKoA 900jtQ8E+cH/Zz/TT7D7qrqmcFznADIQgy0yPdTBmXzddPHqi7ZDUCknOVolMMDUF7+/ nVog== X-Gm-Message-State: ANoB5pkwd/y3b6W2jybUvhfCvtWjDSI+9daB1NZ1ogOg/jhnrgJEVERq +OejhYBWKNI9mEwSGMW5MVg= X-Google-Smtp-Source: AA0mqf6Jl8uOa4Rz1+yh5/7zZycqw7TPxBJCyJ7DCDV8obZokSAlOtp2ltoe5u1/pUfxbhCMra5Pqw== X-Received: by 2002:a17:902:ea91:b0:186:880c:1680 with SMTP id x17-20020a170902ea9100b00186880c1680mr12576845plb.164.1669237090934; Wed, 23 Nov 2022 12:58:10 -0800 (PST) Received: from bvanassche-glaptop2.roam.corp.google.com ([2601:642:4c02:686d:4311:4764:eee7:ac6d]) by smtp.gmail.com with ESMTPSA id i89-20020a17090a3de200b0020b2082e0acsm1858809pjc.0.2022.11.23.12.58.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Nov 2022 12:58:10 -0800 (PST) From: Bart Van Assche To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, Christoph Hellwig , Adrian Hunter , Avri Altman , Bart Van Assche , Ming Lei , Keith Busch Subject: [PATCH v2 4/8] block: Add support for filesystem requests and small segments Date: Wed, 23 Nov 2022 12:57:36 -0800 Message-Id: <20221123205740.463185-5-bvanassche@acm.org> X-Mailer: git-send-email 2.38.1.584.g0f3c55d4c2-goog In-Reply-To: <20221123205740.463185-1-bvanassche@acm.org> References: <20221123205740.463185-1-bvanassche@acm.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Add support in the bio splitting code and also in the bio submission code for bios with segments smaller than the page size. Cc: Christoph Hellwig Cc: Ming Lei Cc: Keith Busch Signed-off-by: Bart Van Assche --- block/blk-merge.c | 6 ++++-- block/blk-mq.c | 2 ++ block/blk.h | 3 ++- 3 files changed, 8 insertions(+), 3 deletions(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index 35a8f75cc45d..7badfbed09fc 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -294,7 +294,8 @@ static struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim, if (nsegs < lim->max_segments && bytes + bv.bv_len <= max_bytes && bv.bv_offset + bv.bv_len <= PAGE_SIZE) { - nsegs++; + /* single-page bvec optimization */ + nsegs += blk_segments(lim, bv.bv_len); bytes += bv.bv_len; } else { if (bvec_split_segs(lim, &bv, &nsegs, &bytes, @@ -531,7 +532,8 @@ static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio, __blk_segment_map_sg_merge(q, &bvec, &bvprv, sg)) goto next_bvec; - if (bvec.bv_offset + bvec.bv_len <= PAGE_SIZE) + if (bvec.bv_offset + bvec.bv_len <= PAGE_SIZE && + bvec.bv_len <= q->limits.max_segment_size) nsegs += __blk_bvec_map_sg(bvec, sglist, sg); else nsegs += blk_bvec_map_sg(q, &bvec, sglist, sg); diff --git a/block/blk-mq.c b/block/blk-mq.c index f72164429446..1560e4f76f2d 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2953,6 +2953,8 @@ void blk_mq_submit_bio(struct bio *bio) bio = blk_queue_bounce(bio, q); if (bio_may_exceed_limits(bio, &q->limits)) bio = __bio_split_to_limits(bio, &q->limits, &nr_segs); + else if (bio->bi_vcnt == 1) + nr_segs = blk_segments(&q->limits, bio->bi_io_vec[0].bv_len); if (!bio_integrity_prep(bio)) return; diff --git a/block/blk.h b/block/blk.h index fb486eff3eef..c45f86b74b1d 100644 --- a/block/blk.h +++ b/block/blk.h @@ -320,7 +320,7 @@ static inline bool bio_may_exceed_limits(struct bio *bio, } /* - * All drivers must accept single-segments bios that are <= PAGE_SIZE. + * Check whether bio splitting should be performed. * This is a quick and dirty check that relies on the fact that * bi_io_vec[0] is always valid if a bio has data. The check might * lead to occasional false negatives when bios are cloned, but compared @@ -328,6 +328,7 @@ static inline bool bio_may_exceed_limits(struct bio *bio, * doesn't matter anyway. */ return lim->chunk_sectors || bio->bi_vcnt != 1 || + bio->bi_io_vec->bv_len > lim->max_segment_size || bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE; }