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=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 F0680C2D0A3 for ; Tue, 3 Nov 2020 18:51:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9DC6A216C4 for ; Tue, 3 Nov 2020 18:51:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ZVrkIhH1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729449AbgKCSvL (ORCPT ); Tue, 3 Nov 2020 13:51:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726660AbgKCSvL (ORCPT ); Tue, 3 Nov 2020 13:51:11 -0500 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 45DFFC0613D1 for ; Tue, 3 Nov 2020 10:51:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=GlWsb7PWBsYhiCP9lpzWE6ufMPsuCzixYv4qLK6TTBY=; b=ZVrkIhH1ZF3z5Fr9vfeGkc2TsM ycxrrwTER/1HQIUFQ9zndsrGTpo0NlFPWAtnEUzdz5Ax9MeehO+bPS2WW5a7bblP/v1ZvUHH14xdE DmHObug4yS7Zz0rSWFLupUs6HgMzY6kZqIv8JNW45nWJY6mT6Vjl/46cX6aHxh5TKlMiW3W2xaLnK 9lOlUIZlujViBIZagTJSmTN14fuADVODaBXRefNchb0HnD6obYTSqxd+NI3JKVTFvjyjPyEg57TZj CI3X2J2AD3SJMF+gch0giXHrP6gw672QnbeINQJcwjJZeyCGlo7qBfMv0bNQETOqy6UqReBd8Ay5W iD3fGWHA==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1ka1OU-0005Ms-IT; Tue, 03 Nov 2020 18:50:58 +0000 Date: Tue, 3 Nov 2020 18:50:58 +0000 From: Christoph Hellwig To: Paul Cercueil Cc: David Airlie , Daniel Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , od@zcrc.me, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/5] drm: Add and export function drm_gem_cma_mmap_noncoherent Message-ID: <20201103185058.GA20134@infradead.org> References: <20201102220651.22069-1-paul@crapouillou.net> <20201102220651.22069-4-paul@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201102220651.22069-4-paul@crapouillou.net> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 02, 2020 at 10:06:49PM +0000, Paul Cercueil wrote: > This function can be used by drivers that need to mmap dumb buffers > created with non-coherent backing memory. > > Signed-off-by: Paul Cercueil > --- > drivers/gpu/drm/drm_gem_cma_helper.c | 39 ++++++++++++++++++++++++++++ > include/drm/drm_gem_cma_helper.h | 2 ++ > 2 files changed, 41 insertions(+) > > diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c > index 3bdd67795e20..4ed63f4896bd 100644 > --- a/drivers/gpu/drm/drm_gem_cma_helper.c > +++ b/drivers/gpu/drm/drm_gem_cma_helper.c > @@ -387,6 +387,45 @@ int drm_gem_cma_mmap(struct file *filp, struct vm_area_struct *vma) > } > EXPORT_SYMBOL_GPL(drm_gem_cma_mmap); > > +/** > + * drm_gem_cma_mmap_noncoherent - memory-map a CMA GEM object with > + * non-coherent cache attribute > + * @filp: file object > + * @vma: VMA for the area to be mapped > + * > + * Just like drm_gem_cma_mmap, but for a GEM object backed by non-coherent > + * memory. > + * > + * Returns: > + * 0 on success or a negative error code on failure. > + */ > +int drm_gem_cma_mmap_noncoherent(struct file *filp, struct vm_area_struct *vma) > +{ > + struct drm_gem_cma_object *cma_obj; > + int ret; > + > + ret = drm_gem_mmap(filp, vma); > + if (ret) > + return ret; > + > + cma_obj = to_drm_gem_cma_obj(vma->vm_private_data); > + > + /* > + * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the > + * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map > + * the whole buffer. > + */ > + vma->vm_flags &= ~VM_PFNMAP; > + vma->vm_pgoff = 0; > + vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); > + > + return remap_pfn_range(vma, vma->vm_start, > + cma_obj->paddr >> PAGE_SHIFT, > + vma->vm_end - vma->vm_start, > + vma->vm_page_prot); Per patch 1 cma_obj->paddr is the dma address, while remap_pfn_range expects a physical address. This does not work.