From patchwork Thu Jun 20 16:12:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11007261 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 3CD6514DB for ; Thu, 20 Jun 2019 16:14:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 303A828742 for ; Thu, 20 Jun 2019 16:14:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 24ED0287B4; Thu, 20 Jun 2019 16:14:03 +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=unavailable 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 8A96B28742 for ; Thu, 20 Jun 2019 16:14:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732222AbfFTQNC (ORCPT ); Thu, 20 Jun 2019 12:13:02 -0400 Received: from ale.deltatee.com ([207.54.116.67]:59544 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732211AbfFTQNB (ORCPT ); Thu, 20 Jun 2019 12:13:01 -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 1hdzg6-00046S-68; Thu, 20 Jun 2019 10:12:59 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.89) (envelope-from ) id 1hdzg4-0005wQ-RP; 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 10:12:23 -0600 Message-Id: <20190620161240.22738-12-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 11/28] block: Create blk_segment_split_ctx 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-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@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() needs to be moved into a generic helper. Step one to do this is to put some of the variables used inside the loop into a context structure so we don't need to pass a dozen variables to this new function. Signed-off-by: Logan Gunthorpe --- block/blk-merge.c | 55 ++++++++++++++++++++++++++++++----------------- 1 file changed, 35 insertions(+), 20 deletions(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index 3581c7ac3c1b..414e61a714bf 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -201,63 +201,78 @@ static bool bvec_split_segs(struct request_queue *q, struct bio_vec *bv, sectors, max_segs); } +struct blk_segment_split_ctx { + unsigned nsegs; + unsigned sectors; + + bool prv_valid; + struct bio_vec bvprv; + + const unsigned max_sectors; + const unsigned max_segs; +}; + static struct bio *blk_bio_segment_split(struct request_queue *q, struct bio *bio, struct bio_set *bs, unsigned *segs) { - struct bio_vec bv, bvprv, *bvprvp = NULL; + struct bio_vec bv; struct bvec_iter iter; - unsigned nsegs = 0, sectors = 0; bool do_split = true; struct bio *new = NULL; - const unsigned max_sectors = get_max_io_size(q, bio); - const unsigned max_segs = queue_max_segments(q); + + struct blk_segment_split_ctx ctx = { + .max_sectors = get_max_io_size(q, bio), + .max_segs = queue_max_segments(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 (bvprvp && bvec_gap_to_prev(q, bvprvp, bv.bv_offset)) + if (ctx.prv_valid && bvec_gap_to_prev(q, &ctx.bvprv, + bv.bv_offset)) goto split; - if (sectors + (bv.bv_len >> 9) > max_sectors) { + 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 (nsegs < max_segs && - sectors < max_sectors) { + if (ctx.nsegs < ctx.max_segs && + ctx.sectors < ctx.max_sectors) { /* split in the middle of bvec */ - bv.bv_len = (max_sectors - sectors) << 9; - bvec_split_segs(q, &bv, &nsegs, - §ors, max_segs); + bv.bv_len = + (ctx.max_sectors - ctx.sectors) << 9; + bvec_split_segs(q, &bv, &ctx.nsegs, + &ctx.sectors, ctx.max_segs); } goto split; } - if (nsegs == max_segs) + if (ctx.nsegs == ctx.max_segs) goto split; - bvprv = bv; - bvprvp = &bvprv; + ctx.bvprv = bv; + ctx.prv_valid = true; if (bv.bv_offset + bv.bv_len <= PAGE_SIZE) { - nsegs++; - sectors += bv.bv_len >> 9; - } else if (bvec_split_segs(q, &bv, &nsegs, §ors, - max_segs)) { + 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 = false; split: - *segs = nsegs; + *segs = ctx.nsegs; if (do_split) { - new = bio_split(bio, sectors, GFP_NOIO, bs); + new = bio_split(bio, ctx.sectors, GFP_NOIO, bs); if (new) bio = new; }