From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964907Ab2CTVXO (ORCPT ); Tue, 20 Mar 2012 17:23:14 -0400 Received: from mail-wi0-f178.google.com ([209.85.212.178]:55693 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753832Ab2CTVXM (ORCPT ); Tue, 20 Mar 2012 17:23:12 -0400 Date: Tue, 20 Mar 2012 22:23:51 +0100 From: Daniel Vetter To: linaro-mm-sig@lists.linaro.org, LKML , DRI Development , linux-media@vger.kernel.org Cc: Daniel Vetter Subject: Re: [PATCH] [RFC] dma-buf: mmap support Message-ID: <20120320212013.GA22215@phenom.ffwll.local> Mail-Followup-To: linaro-mm-sig@lists.linaro.org, LKML , DRI Development , linux-media@vger.kernel.org References: <1332276785-1440-1-git-send-email-daniel.vetter@ffwll.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1332276785-1440-1-git-send-email-daniel.vetter@ffwll.ch> X-Operating-System: Linux phenom 3.2.0-1-amd64 User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 20, 2012 at 09:53:05PM +0100, Daniel Vetter wrote: > Note taht this dma-buf mmap patch does _not_ support every possible > insanity an existing subsystem could pull of with mmap: Because it > does not allow to intercept pagefaults and shoot down ptes importing > subsystems can't add some magic of their own at these points (e.g. to > automatically synchronize with outstanding rendering or set up some > special resources). I've done a cursory read through a few mmap > implementions of various subsytems and I'm hopeful that we can avoid > this (and the complexity it'd bring with it). To clarify: This concerns the importer. The exporter is of course still free to do whatever it pleases. But the goal of this exercise is that importing subsystems can still offer an identical userspace interfaces for buffers imported through dma-buf and native ones, hence why I've mentioned it. -Daniel -- Daniel Vetter Mail: daniel@ffwll.ch Mobile: +41 (0)79 365 57 48