From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0B1DEC7618F for ; Tue, 16 Jul 2019 21:45:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC510206C2 for ; Tue, 16 Jul 2019 21:45:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="d0XRWLaf" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731021AbfGPVpA (ORCPT ); Tue, 16 Jul 2019 17:45:00 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:45380 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726794AbfGPVpA (ORCPT ); Tue, 16 Jul 2019 17:45:00 -0400 Received: by mail-pg1-f194.google.com with SMTP id o13so10061286pgp.12 for ; Tue, 16 Jul 2019 14:45:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=4drR0FDgR1qKvDPf6ArOgp5GWnRtGoeeH0ezG721TC0=; b=d0XRWLafSldOVujZRpCkAu9+YwaiUggcPzRRQGuqpuKlW6jllCs6aNRjoFTQhxg4W6 z7ImjRNh5QmIhLrvG3LhZo0PIw8SLsbPLLxFxaZOy4h7hkmlvhGkc1vtL4Gsa4mkCHz1 zJ+OWNjBPEuKNabEYJEFz46fx9LgdzRJWPcElIRSmJJG5lufLlzetP7GPCAmZHS6V2xl 2mxK1+ye+N5ayG7/d9N0ag+WZAL7AAonPq26ki8Ch07dIWP/z73zocHpTVI4WSb32Wj/ 4Wly/viUTLx9SnnoMfTR1xsYZJ0YcZ3G/B7jx6HPwUu0T3GhkwGGo8T1bQV9zgTEmpzR PxIA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=4drR0FDgR1qKvDPf6ArOgp5GWnRtGoeeH0ezG721TC0=; b=GkLdWQ+9PlYWKwIUMSKBuGyX4ndPaGsZLjiO6yh11XdlPXiBhTvG+VtG1CJ7NE4igk 4Wsoa0rd9ArwtUpJq4HeBu12EB3YkjghHD4q9fEz9D0x7Ht76Au/Pn/ikDni7josRik7 obxRoHZoT9IuDmybm3EZZg/8H1EtEJU7LpApvHB8UoENRg+nzfskgr76GkMiQ79nF39c LwjdILSoP0FCZPxHso24R7h+HfI3wPegF/kcFKELqjMgjkH7Q6jdoB7LiD5GbREvB4uM y6M2PLwlsIuPzVRT9C7kgpNngoGGEHpNJmdWR8Rv/yP6MblHrIZvUZM4wjssX+AI586e 6dzw== X-Gm-Message-State: APjAAAUAEzGNvrKn6JhP7VYel+uuhB/yqkCcEuvecSIiChn6gZ4XO1eZ D0NR7Ieqb6HMj+plbpHtfcs1pXIKtVg= X-Google-Smtp-Source: APXvYqxiDio1TWrmNR0NEynX+8QmbTFyvAzkbSoW72UZvLkMfedCjFiKOzRrZlV77GO0V2OJitoyeQ== X-Received: by 2002:a17:90a:5887:: with SMTP id j7mr39000839pji.136.1563313499680; Tue, 16 Jul 2019 14:44:59 -0700 (PDT) Received: from localhost ([100.118.89.203]) by smtp.gmail.com with ESMTPSA id 135sm20978687pfb.137.2019.07.16.14.44.58 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 16 Jul 2019 14:44:59 -0700 (PDT) From: Rob Clark To: dri-devel@lists.freedesktop.org Cc: Chris Wilson , Intel Graphics Development , Rob Clark , David Airlie , Daniel Vetter , Emil Velikov , Eric Anholt , Eric Biggers , Deepak Sharma , linux-kernel@vger.kernel.org Subject: [PATCH v3 3/3] drm/vgem: use normal cached mmap'ings Date: Tue, 16 Jul 2019 14:37:42 -0700 Message-Id: <20190716213746.4670-3-robdclark@gmail.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190716213746.4670-1-robdclark@gmail.com> References: <20190716213746.4670-1-robdclark@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rob Clark Since there is no real device associated with VGEM, it is impossible to end up with appropriate dev->dma_ops, meaning that we have no way to invalidate the shmem pages allocated by VGEM. So, at least on platforms without drm_cflush_pages(), we end up with corruption when cache lines from previous usage of VGEM bo pages get evicted to memory. The only sane option is to use cached mappings. Signed-off-by: Rob Clark --- v3: rebased on drm-tip drivers/gpu/drm/vgem/vgem_drv.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/drivers/gpu/drm/vgem/vgem_drv.c b/drivers/gpu/drm/vgem/vgem_drv.c index e7d12e93b1f0..84262e2bd7f7 100644 --- a/drivers/gpu/drm/vgem/vgem_drv.c +++ b/drivers/gpu/drm/vgem/vgem_drv.c @@ -259,9 +259,6 @@ static int vgem_mmap(struct file *filp, struct vm_area_struct *vma) if (ret) return ret; - /* Keep the WC mmaping set by drm_gem_mmap() but our pages - * are ordinary and not special. - */ vma->vm_flags = flags | VM_DONTEXPAND | VM_DONTDUMP; return 0; } @@ -310,17 +307,17 @@ static void vgem_unpin_pages(struct drm_vgem_gem_object *bo) static int vgem_prime_pin(struct drm_gem_object *obj, struct device *dev) { struct drm_vgem_gem_object *bo = to_vgem_bo(obj); - long n_pages = obj->size >> PAGE_SHIFT; + long i, n_pages = obj->size >> PAGE_SHIFT; struct page **pages; pages = vgem_pin_pages(bo); if (IS_ERR(pages)) return PTR_ERR(pages); - /* Flush the object from the CPU cache so that importers can rely - * on coherent indirect access via the exported dma-address. - */ - drm_clflush_pages(pages, n_pages); + for (i = 0; i < n_pages; i++) { + dma_sync_single_for_device(dev, page_to_phys(pages[i]), + PAGE_SIZE, DMA_BIDIRECTIONAL); + } return 0; } @@ -328,6 +325,13 @@ static int vgem_prime_pin(struct drm_gem_object *obj, struct device *dev) static void vgem_prime_unpin(struct drm_gem_object *obj, struct device *dev) { struct drm_vgem_gem_object *bo = to_vgem_bo(obj); + long i, n_pages = obj->size >> PAGE_SHIFT; + struct page **pages = bo->pages; + + for (i = 0; i < n_pages; i++) { + dma_sync_single_for_cpu(dev, page_to_phys(pages[i]), + PAGE_SIZE, DMA_BIDIRECTIONAL); + } vgem_unpin_pages(bo); } @@ -382,7 +386,7 @@ static void *vgem_prime_vmap(struct drm_gem_object *obj) if (IS_ERR(pages)) return NULL; - return vmap(pages, n_pages, 0, pgprot_writecombine(PAGE_KERNEL)); + return vmap(pages, n_pages, 0, PAGE_KERNEL); } static void vgem_prime_vunmap(struct drm_gem_object *obj, void *vaddr) @@ -411,7 +415,7 @@ static int vgem_prime_mmap(struct drm_gem_object *obj, fput(vma->vm_file); vma->vm_file = get_file(obj->filp); vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; - vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); return 0; } -- 2.21.0