From patchwork Fri Jan 28 00:26:09 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12727627 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0B8FC4167E for ; Fri, 28 Jan 2022 00:26:45 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ECBBA8D0001; Thu, 27 Jan 2022 19:26:31 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E7B8D6B0080; Thu, 27 Jan 2022 19:26:31 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C58AE6B0082; Thu, 27 Jan 2022 19:26:31 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0252.hostedemail.com [216.40.44.252]) by kanga.kvack.org (Postfix) with ESMTP id A59686B0080 for ; Thu, 27 Jan 2022 19:26:31 -0500 (EST) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 58A7B8249980 for ; Fri, 28 Jan 2022 00:26:31 +0000 (UTC) X-FDA: 79077804582.21.A737C1E Received: from ale.deltatee.com (ale.deltatee.com [204.191.154.188]) by imf30.hostedemail.com (Postfix) with ESMTP id 8942080003 for ; Fri, 28 Jan 2022 00:26:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-Id:Date:Cc:To:From:content-disposition; bh=UO35KE8YVx2v+yNTFMhmKCQE8ptUbM1lG6ODy8MFD4U=; b=sBbcFg82SAk1otTpMskAScMiG7 RyAKAQkLTz1xmy8xTlaHSy36dHLKBWxmZ36QoMwA4kkP1Jl1psr1WnOOxIkWmE9XtLADFmwdP9Al8 ICSCs2cktw8nLKLELqHswQ/9zbp0P2ctwkft2z7KTrR3Sn8uIMRmhiPnKpbppo9L3h5AIBakUCRp6 ACGKOFIT2MqbGv8JvJsn9xNK3WT0DFPSr3AFe/PofI/wklbT7AxT8jWUom0daiNDBGZ6rcIONs0MR Hx6YbD9XhVp29jfmuXGV9Ri0UA0Ly2AAO8I6iJbJsPYwK+DBu9x+77HhVcbEqqwc0x0ilK1AB7U1m XP4zUiFw==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1nDF5r-005OcV-Sd; Thu, 27 Jan 2022 17:26:25 -0700 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.94.2) (envelope-from ) id 1nDF5p-0001dH-Dg; Thu, 27 Jan 2022 17:26:21 -0700 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org Cc: Stephen Bates , Christoph Hellwig , Dan Williams , Jason Gunthorpe , =?utf-8?q?Christian_K=C3=B6nig?= , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Bjorn Helgaas , Ira Weiny , Robin Murphy , Martin Oliveira , Chaitanya Kulkarni , Ralph Campbell , Logan Gunthorpe Date: Thu, 27 Jan 2022 17:26:09 -0700 Message-Id: <20220128002614.6136-20-logang@deltatee.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220128002614.6136-1-logang@deltatee.com> References: <20220128002614.6136-1-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-mm@kvack.org, iommu@lists.linux-foundation.org, sbates@raithlin.com, hch@lst.de, jgg@ziepe.ca, christian.koenig@amd.com, ddutile@redhat.com, willy@infradead.org, daniel.vetter@ffwll.ch, jason@jlekstrand.net, dave.hansen@linux.intel.com, helgaas@kernel.org, dan.j.williams@intel.com, andrzej.jakowski@intel.com, dave.b.minturn@intel.com, jianxin.xiong@intel.com, ira.weiny@intel.com, robin.murphy@arm.com, martin.oliveira@eideticom.com, ckulkarnilinux@gmail.com, jhubbard@nvidia.com, rcampbell@nvidia.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v5 19/24] lib/scatterlist: add check when merging zone device pages X-SA-Exim-Version: 4.2.1 (built Sat, 13 Feb 2021 17:57:42 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) X-Rspamd-Server: rspam11 X-Rspamd-Queue-Id: 8942080003 X-Stat-Signature: hwto5kmo4dc9xsfao5gkhx7jtsjzc415 Authentication-Results: imf30.hostedemail.com; dkim=pass header.d=deltatee.com header.s=20200525 header.b=sBbcFg82; dmarc=pass (policy=none) header.from=deltatee.com; spf=pass (imf30.hostedemail.com: domain of gunthorp@deltatee.com designates 204.191.154.188 as permitted sender) smtp.mailfrom=gunthorp@deltatee.com X-Rspam-User: nil X-HE-Tag: 1643329589-948783 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Consecutive zone device pages should not be merged into the same sgl or bvec segment with other types of pages or if they belong to different pgmaps. Otherwise getting the pgmap of a given segment is not possible without scanning the entire segment. This helper returns true either if both pages are not zone device pages or both pages are zone device pages with the same pgmap. Factor out the check for page mergability into a pages_are_mergable() helper and add a check with zone_device_pages_are_mergeable(). Signed-off-by: Logan Gunthorpe --- lib/scatterlist.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/lib/scatterlist.c b/lib/scatterlist.c index d5e82e4a57ad..af53a0984f76 100644 --- a/lib/scatterlist.c +++ b/lib/scatterlist.c @@ -410,6 +410,15 @@ static struct scatterlist *get_next_sg(struct sg_append_table *table, return new_sg; } +static bool pages_are_mergeable(struct page *a, struct page *b) +{ + if (page_to_pfn(a) != page_to_pfn(b) + 1) + return false; + if (!zone_device_pages_have_same_pgmap(a, b)) + return false; + return true; +} + /** * sg_alloc_append_table_from_pages - Allocate and initialize an append sg * table from an array of pages @@ -447,6 +456,7 @@ int sg_alloc_append_table_from_pages(struct sg_append_table *sgt_append, unsigned int chunks, cur_page, seg_len, i, prv_len = 0; unsigned int added_nents = 0; struct scatterlist *s = sgt_append->prv; + struct page *last_pg; /* * The algorithm below requires max_segment to be aligned to PAGE_SIZE @@ -460,21 +470,17 @@ int sg_alloc_append_table_from_pages(struct sg_append_table *sgt_append, return -EOPNOTSUPP; if (sgt_append->prv) { - unsigned long paddr = - (page_to_pfn(sg_page(sgt_append->prv)) * PAGE_SIZE + - sgt_append->prv->offset + sgt_append->prv->length) / - PAGE_SIZE; - if (WARN_ON(offset)) return -EINVAL; /* Merge contiguous pages into the last SG */ prv_len = sgt_append->prv->length; - while (n_pages && page_to_pfn(pages[0]) == paddr) { + last_pg = sg_page(sgt_append->prv); + while (n_pages && pages_are_mergeable(last_pg, pages[0])) { if (sgt_append->prv->length + PAGE_SIZE > max_segment) break; sgt_append->prv->length += PAGE_SIZE; - paddr++; + last_pg = pages[0]; pages++; n_pages--; } @@ -488,7 +494,7 @@ int sg_alloc_append_table_from_pages(struct sg_append_table *sgt_append, for (i = 1; i < n_pages; i++) { seg_len += PAGE_SIZE; if (seg_len >= max_segment || - page_to_pfn(pages[i]) != page_to_pfn(pages[i - 1]) + 1) { + !pages_are_mergeable(pages[i], pages[i - 1])) { chunks++; seg_len = 0; } @@ -504,8 +510,7 @@ int sg_alloc_append_table_from_pages(struct sg_append_table *sgt_append, for (j = cur_page + 1; j < n_pages; j++) { seg_len += PAGE_SIZE; if (seg_len >= max_segment || - page_to_pfn(pages[j]) != - page_to_pfn(pages[j - 1]) + 1) + !pages_are_mergeable(pages[j], pages[j - 1])) break; }