From patchwork Thu Jun 20 16:12:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11007285 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4B74C14DB for ; Thu, 20 Jun 2019 16:14:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E32328756 for ; Thu, 20 Jun 2019 16:14:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 326E22228E; Thu, 20 Jun 2019 16:14:16 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C0F5228756 for ; Thu, 20 Jun 2019 16:14:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732418AbfFTQOO (ORCPT ); Thu, 20 Jun 2019 12:14:14 -0400 Received: from ale.deltatee.com ([207.54.116.67]:59490 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732175AbfFTQM6 (ORCPT ); Thu, 20 Jun 2019 12:12:58 -0400 Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hdzgA-00046T-NQ; Thu, 20 Jun 2019 10:12:57 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1hdzg4-0005wT-V5; Thu, 20 Jun 2019 10:12:44 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org Cc: Jens Axboe , Christoph Hellwig , Bjorn Helgaas , Dan Williams , Sagi Grimberg , Keith Busch , Jason Gunthorpe , Stephen Bates , Logan Gunthorpe Date: Thu, 20 Jun 2019 10:12:24 -0600 Message-Id: <20190620161240.22738-13-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190620161240.22738-1-logang@deltatee.com> References: <20190620161240.22738-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-rdma@vger.kernel.org, axboe@kernel.dk, hch@lst.de, bhelgaas@google.com, dan.j.williams@intel.com, sagi@grimberg.me, kbusch@kernel.org, jgg@ziepe.ca, sbates@raithlin.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [RFC PATCH 12/28] block: Create helper for bvec_should_split() X-SA-Exim-Version: 4.2.1 (built Tue, 02 Aug 2016 21:08:31 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP In order to support dma-direct bios, blk_bio_segment_split() will need to operate on both bio_vecs and dma_vecs. In order to do this, the code inside bio_for_each_bvec() is moved into a generic helper called bvec_should_split(). Signed-off-by: Logan Gunthorpe --- block/blk-merge.c | 86 +++++++++++++++++++++++++---------------------- 1 file changed, 46 insertions(+), 40 deletions(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index 414e61a714bf..d9e89c0ad40d 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -212,6 +212,48 @@ struct blk_segment_split_ctx { const unsigned max_segs; }; +static bool bvec_should_split(struct request_queue *q, struct bio_vec *bv, + struct blk_segment_split_ctx *ctx) +{ + /* + * If the queue doesn't support SG gaps and adding this + * offset would create a gap, disallow it. + */ + if (ctx->prv_valid && bvec_gap_to_prev(q, &ctx->bvprv, bv->bv_offset)) + return true; + + if (ctx->sectors + (bv->bv_len >> 9) > ctx->max_sectors) { + /* + * Consider this a new segment if we're splitting in + * the middle of this vector. + */ + if (ctx->nsegs < ctx->max_segs && + ctx->sectors < ctx->max_sectors) { + /* split in the middle of bvec */ + bv->bv_len = (ctx->max_sectors - ctx->sectors) << 9; + bvec_split_segs(q, bv, &ctx->nsegs, + &ctx->sectors, ctx->max_segs); + } + return true; + } + + if (ctx->nsegs == ctx->max_segs) + return true; + + ctx->bvprv = *bv; + ctx->prv_valid = true; + + if (bv->bv_offset + bv->bv_len <= PAGE_SIZE) { + ctx->nsegs++; + ctx->sectors += bv->bv_len >> 9; + } else if (bvec_split_segs(q, bv, &ctx->nsegs, &ctx->sectors, + ctx->max_segs)) { + return true; + } + + return false; +} + static struct bio *blk_bio_segment_split(struct request_queue *q, struct bio *bio, struct bio_set *bs, @@ -219,7 +261,7 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, { struct bio_vec bv; struct bvec_iter iter; - bool do_split = true; + bool do_split = false; struct bio *new = NULL; struct blk_segment_split_ctx ctx = { @@ -228,47 +270,11 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, }; bio_for_each_bvec(bv, bio, iter) { - /* - * If the queue doesn't support SG gaps and adding this - * offset would create a gap, disallow it. - */ - if (ctx.prv_valid && bvec_gap_to_prev(q, &ctx.bvprv, - bv.bv_offset)) - goto split; - - if (ctx.sectors + (bv.bv_len >> 9) > ctx.max_sectors) { - /* - * Consider this a new segment if we're splitting in - * the middle of this vector. - */ - if (ctx.nsegs < ctx.max_segs && - ctx.sectors < ctx.max_sectors) { - /* split in the middle of bvec */ - bv.bv_len = - (ctx.max_sectors - ctx.sectors) << 9; - bvec_split_segs(q, &bv, &ctx.nsegs, - &ctx.sectors, ctx.max_segs); - } - goto split; - } - - if (ctx.nsegs == ctx.max_segs) - goto split; - - ctx.bvprv = bv; - ctx.prv_valid = true; - - if (bv.bv_offset + bv.bv_len <= PAGE_SIZE) { - ctx.nsegs++; - ctx.sectors += bv.bv_len >> 9; - } else if (bvec_split_segs(q, &bv, &ctx.nsegs, &ctx.sectors, - ctx.max_segs)) { - goto split; - } + do_split = bvec_should_split(q, &bv, &ctx); + if (do_split) + break; } - do_split = false; -split: *segs = ctx.nsegs; if (do_split) {