From patchwork Wed Nov 17 21:54:04 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12625519 X-Patchwork-Delegate: bhelgaas@google.com 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31CAEC433EF for ; Wed, 17 Nov 2021 21:55:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 20CD961BE5 for ; Wed, 17 Nov 2021 21:55:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241144AbhKQV6H (ORCPT ); Wed, 17 Nov 2021 16:58:07 -0500 Received: from ale.deltatee.com ([204.191.154.188]:58808 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240888AbhKQV5Y (ORCPT ); Wed, 17 Nov 2021 16:57:24 -0500 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=sIc/9Jpqra/LKYpNc8AVq+YZr9rqCBlMcxeI5w63K9Y=; b=qAabCTSl24l5BPvqCkqk+aNO4/ l35sVoSDBpDSDJegtE06JXOxgptVuWcQMTEEDcHsf/4NUk1ro2yykE8tjlzom72mEdysLMvuAgtbk ZIwgZV926G/lls+vdnSCqpFNiddcie5w4eYAYXjAlPhN9KwlMFD/REUCWD1/Y1q2ZVF9+ZcyQx1Oa /9TWPeQqZwLldM3CCv1ewJqp2oSn+FS8HZOy019zMRBJDPKUBd1lgp+ARI37C0vqIf3g+SEoXX1IM o5AdWxaEKpA5xfkKjzbcuAqzS9I3fzsRYWRZQwdJI1cbLKFcSqF7ZgjmSLkO1miMCsmGDBy/hmwts +kTYNZ8g==; 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 1mnSso-000Zo5-Mj; Wed, 17 Nov 2021 14:54:23 -0700 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.94.2) (envelope-from ) id 1mnSsk-0000zw-TA; Wed, 17 Nov 2021 14:54:18 -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 , Logan Gunthorpe Date: Wed, 17 Nov 2021 14:54:04 -0700 Message-Id: <20211117215410.3695-18-logang@deltatee.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20211117215410.3695-1-logang@deltatee.com> References: <20211117215410.3695-1-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, jhubbard@nvidia.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, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v4 17/23] block: 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) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org 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. Add a helper to determine if zone device pages are mergeable and use this helper in page_is_mergeable(). Signed-off-by: Logan Gunthorpe --- block/bio.c | 2 ++ include/linux/mm.h | 23 +++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/block/bio.c b/block/bio.c index 15ab0d6d1c06..f4e2e30d7a24 100644 --- a/block/bio.c +++ b/block/bio.c @@ -803,6 +803,8 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return false; if (xen_domain() && !xen_biovec_phys_mergeable(bv, page)) return false; + if (!zone_device_pages_are_mergeable(bv->bv_page, page)) + return false; *same_page = ((vec_end_addr & PAGE_MASK) == page_addr); if (*same_page) diff --git a/include/linux/mm.h b/include/linux/mm.h index 65cb27cebbab..3367d936b256 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1118,6 +1118,24 @@ static inline bool is_zone_device_page(const struct page *page) { return page_zonenum(page) == ZONE_DEVICE; } + +/* + * 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. + */ +static inline bool zone_device_pages_are_mergeable(const struct page *a, + const struct page *b) +{ + if (is_zone_device_page(a) != is_zone_device_page(b)) + return false; + if (!is_zone_device_page(a)) + return true; + return a->pgmap == b->pgmap; +} extern void memmap_init_zone_device(struct zone *, unsigned long, unsigned long, struct dev_pagemap *); #else @@ -1125,6 +1143,11 @@ static inline bool is_zone_device_page(const struct page *page) { return false; } +static inline bool zone_device_pages_are_mergeable(const struct page *a, + const struct page *b) +{ + return true; +} #endif static inline bool is_zone_movable_page(const struct page *page)