From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 457DE6B002D for ; Sun, 27 Nov 2011 01:59:34 -0500 (EST) Received: by ywm14 with SMTP id 14so4652310ywm.14 for ; Sat, 26 Nov 2011 22:59:30 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: <1318325033-32688-1-git-send-email-sumit.semwal@ti.com> <1318325033-32688-2-git-send-email-sumit.semwal@ti.com> Date: Sun, 27 Nov 2011 00:59:30 -0600 Message-ID: Subject: Re: [Linaro-mm-sig] [RFC 1/2] dma-buf: Introduce dma buffer sharing mechanism From: Rob Clark Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org List-ID: To: Daniel Vetter Cc: Dave Airlie , Sumit Semwal , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, linux@arm.linux.org.uk, arnd@arndb.de, jesse.barker@linaro.org On Sat, Nov 26, 2011 at 8:00 AM, Daniel Vetter wrote: > On Fri, Nov 25, 2011 at 17:28, Dave Airlie wrote: >> I've rebuilt my PRIME interface on top of dmabuf to see how it would wor= k, >> >> I've got primed gears running again on top, but I expect all my object >> lifetime and memory ownership rules need fixing up (i.e. leaks like a >> sieve). >> >> http://cgit.freedesktop.org/~airlied/linux/log/?h=3Ddrm-prime-dmabuf >> >> has the i915/nouveau patches for the kernel to produce the prime interfa= ce. > > I've noticed that your implementations for get_scatterlist (at least > for the i915 driver) doesn't return the sg table mapped into the > device address space. I've checked and the documentation makes it > clear that this should be the case (and we really need this to support > certain insane hw), but the get/put_scatterlist names are a bit > misleading. Proposal: > > - use struct sg_table instead of scatterlist like you've already done > in you branch. Simply more consistent with the dma api. yup > - rename get/put_scatterlist into map/unmap for consistency with all > the map/unmap dma api functions. The attachement would then serve as > the abstract cookie to the backing storage, similar to how struct page > * works as an abstract cookie for dma_map/unmap_page. The only special > thing is that struct device * parameter because that's already part of > the attachment. yup > - add new wrapper functions dma_buf_map_attachment and > dma_buf_unmap_attachement to hide all the pointer/vtable-chasing that > we currently expose to users of this interface. I thought that was one of the earlier comments on the initial dmabuf patch, but either way: yup BR, -R > Comments? > > Cheers, Daniel > -- > Daniel Vetter > daniel.vetter@ffwll.ch - +41 (0) 79 364 57 48 - http://blog.ffwll.ch > -- > To unsubscribe from this list: send the line "unsubscribe linux-media" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at =A0http://vger.kernel.org/majordomo-info.html > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org