From patchwork Fri Feb 21 18:25:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 11397175 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E503817F0 for ; Fri, 21 Feb 2020 18:26:55 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B6DF4206DB for ; Fri, 21 Feb 2020 18:26:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BIVZZebD" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B6DF4206DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=deltatee.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Subject:MIME-Version:References: In-Reply-To:Message-Id:Date:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OiPkS1GzV/oIpnIiEO79pTl+p6dRK4kePHGTo/Fte7U=; b=BIVZZebDDo3P3E Qnj9ChmRd5UsEr9DWlhMzhSyP9z7L6h/aWeQuPIU8boUPu7FikbBPdqlRSadmAnS2piNcNRwE8PNu XMbmTSNmtub3y5aHOeAJkZCO28/6PXaDngcBF79OAHf0JOd17CrVa7ubXNfeZnikfC1Gkfz9bUTR+ dlzzCCiRyU9XFCz4QG/2oarq/GIjDCBvkarBPDnduK19T27P4f9hPPU7GFTg8EUwdxNP8dy+9MIx8 Km1cQoCznH+35k217R1NBCI8dsxSdyTSPKhXaCx+Dy9z6i4ZZTiGqWXBe1Dc0hjD7/vywpW16ls7e fQ2AGPzzWGh1bDhEq+ag==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1j5D0o-0004K1-B5; Fri, 21 Feb 2020 18:26:54 +0000 Received: from ale.deltatee.com ([207.54.116.67]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1j5CzO-0002y4-SS for linux-arm-kernel@lists.infradead.org; Fri, 21 Feb 2020 18:25:29 +0000 Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1j5CzA-00057s-B6; Fri, 21 Feb 2020 11:25:25 -0700 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1j5Cz3-0007Nt-Mw; Fri, 21 Feb 2020 11:25:05 -0700 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-mm@kvack.org, Dan Williams , Michal Hocko , David Hildenbrand , Andrew Morton Date: Fri, 21 Feb 2020 11:25:03 -0700 Message-Id: <20200221182503.28317-8-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200221182503.28317-1-logang@deltatee.com> References: <20200221182503.28317-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-mm@kvack.org, dan.j.williams@intel.com, akpm@linux-foundation.org, hch@lst.de, catalin.marinas@arm.com, benh@kernel.crashing.org, tglx@linutronix.de, david@redhat.com, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, mhocko@kernel.org, will@kernel.org, luto@kernel.org, peterz@infradead.org, ebadger@gigaio.com, logang@deltatee.com, jgg@ziepe.ca X-SA-Exim-Mail-From: gunthorp@deltatee.com X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on ale.deltatee.com X-Spam-Level: X-Spam-Status: No, score=-8.7 required=5.0 tests=ALL_TRUSTED,BAYES_00, GREYLIST_ISWHITE,MYRULES_NO_TEXT,SURBL_BLOCKED,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.2 Subject: [PATCH v3 7/7] mm/memremap: Set caching mode for PCI P2PDMA memory to WC X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200221_102527_097660_FC21AECE X-CRM114-Status: GOOD ( 12.03 ) X-Spam-Score: -0.0 (/) X-Spam-Report: SpamAssassin version 3.4.3 on bombadil.infradead.org summary: Content analysis details: (-0.0 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at https://www.dnswl.org/, no trust [207.54.116.67 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 SPF_HELO_PASS SPF: HELO matches SPF record X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eric Badger , Peter Zijlstra , Catalin Marinas , Dave Hansen , Jason Gunthorpe , Logan Gunthorpe , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Benjamin Herrenschmidt , Thomas Gleixner , Will Deacon , Christoph Hellwig Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org PCI BAR IO memory should never be mapped as WB, however prior to this the PAT bits were set WB and it was typically overridden by MTRR registers set by the firmware. Set PCI P2PDMA memory to be WC (writecombining) as the only current user (the NVMe CMB) was originally mapped WC before the P2PDMA code replaced the mapping with devm_memremap_pages(). Future use-cases may need to generalize this by adding flags to select the caching type, as some P2PDMA cases will not want WC. However, those use-cases are not upstream yet and this can be changed when they arrive. Cc: Dan Williams Cc: Christoph Hellwig Cc: Jason Gunthorpe Signed-off-by: Logan Gunthorpe Reviewed-by: Dan Williams --- mm/memremap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/memremap.c b/mm/memremap.c index 06742372a203..8d141c3e3364 100644 --- a/mm/memremap.c +++ b/mm/memremap.c @@ -190,7 +190,10 @@ void *memremap_pages(struct dev_pagemap *pgmap, int nid) } break; case MEMORY_DEVICE_DEVDAX: + need_devmap_managed = false; + break; case MEMORY_DEVICE_PCI_P2PDMA: + params.pgprot = pgprot_writecombine(params.pgprot); need_devmap_managed = false; break; default: