From patchwork Tue Jun 3 13:56:28 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Courbot X-Patchwork-Id: 4288971 Return-Path: X-Original-To: patchwork-dri-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 5EB0C9F333 for ; Tue, 3 Jun 2014 14:24:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 824E120279 for ; Tue, 3 Jun 2014 14:24:19 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by mail.kernel.org (Postfix) with ESMTP id 3D6A920259 for ; Tue, 3 Jun 2014 14:24:18 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 62EF66E3CE; Tue, 3 Jun 2014 07:24:16 -0700 (PDT) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org X-Greylist: delayed 1470 seconds by postgrey-1.34 at gabe; Tue, 03 Jun 2014 07:24:15 PDT Received: from mail.gnurou.org (gnurou.org [207.192.72.5]) by gabe.freedesktop.org (Postfix) with ESMTP id 53E106E3CE; Tue, 3 Jun 2014 07:24:15 -0700 (PDT) Received: from localhost.localdomain (softbank126010191003.bbtec.net [126.10.191.3]) by mail.gnurou.org (Postfix) with ESMTPSA id 87393167E15; Tue, 3 Jun 2014 23:00:08 +0900 (JST) From: Alexandre Courbot To: Ben Skeggs , Thierry Reding Subject: [PATCH] drm/nouveau/vm: fix mapping of SG pages list Date: Tue, 3 Jun 2014 22:56:28 +0900 Message-Id: <1401803788-21494-1-git-send-email-acourbot@nvidia.com> X-Mailer: git-send-email 2.0.0 Cc: gnurou@gmail.com, nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-tegra@vger.kernel.org X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Spam-Status: No, score=-4.8 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP SG pages lists (not to be confused with scatterlists) are a list of 4KB memory pages used to define a nouveau_mem. Mapping them to a VM that does not use 4KB apertures resulted in each subsequent 4KB physical page being mapped into a larger VM aperture, thus creating an incorrect, overlapping mapping. This patch fixes this issue by detecting when such mappings occur and by skipping the required number of pages in the list to ensure a correct linear mapping. Signed-off-by: Alexandre Courbot --- Ben, how does this look? This issue has been highlighted by the GK20A RAM driver which makes use of nouveau_mem::pages to provide system memory. The mapping overlap resulted in rendering issues for buffers that were bigger than 1 big VM page. I believe this is the correct way to fix this, and this way of building nouveau_mem instances is not much used in the driver anyway, but you know better. :) drivers/gpu/drm/nouveau/core/subdev/vm/base.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/nouveau/core/subdev/vm/base.c b/drivers/gpu/drm/nouveau/core/subdev/vm/base.c index 7dd680f..db35e8d 100644 --- a/drivers/gpu/drm/nouveau/core/subdev/vm/base.c +++ b/drivers/gpu/drm/nouveau/core/subdev/vm/base.c @@ -152,13 +152,18 @@ nouveau_vm_map_sg(struct nouveau_vma *vma, u64 delta, u64 length, end = (pte + num); if (unlikely(end >= max)) end = max; - len = end - pte; + + /* + * Map pages >4KB one by one so we can fix the list pointer + * as to not map intermediate pages to the next PTE + */ + len = bits ? 1 : end - pte; vmm->map_sg(vma, pgt, mem, pte, len, list); num -= len; pte += len; - list += len; + list += len << bits; if (unlikely(end >= max)) { pde++; pte = 0;