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=-2.2 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=unavailable 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 0EC21C04EB8 for ; Wed, 12 Dec 2018 09:09:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BF28820849 for ; Wed, 12 Dec 2018 09:09:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="Hl3KljdR" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BF28820849 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-media-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726851AbeLLJJc (ORCPT ); Wed, 12 Dec 2018 04:09:32 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:60872 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726813AbeLLJJa (ORCPT ); Wed, 12 Dec 2018 04:09:30 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=MEuYYn3BaHHXkDWWKQAaU7ww1MsDEvyrrWt5TN+W4o8=; b=Hl3KljdRZsYgBumVPEtjQwwjy sTQwVLYUOc5dJWFbFGPIqiUNdFxzmENBAfbrZHbOliwAGFkSaCGGjEUoRY/FI19mP5nchlk5oOkCy 0XW/Kv7LAsCDdYIEe88mWuoEJb7h23yo0KP1guVuxK2z92/VFfIGbfWochRU7nhswZUzGToPFWync 8Hq5VLwlvTk1vYYpAo6Tn5mUFo2MtPiHDRaYOMevV3wsZHUT9hsgnVKMbQXZ6Vs3V5/xUWZ/Dq9SD lXVx/lJulafcv+9I4vAcMVdq/kg/oNqf1fX23zydTQSf2dZrKSL/v50z4WXKqzVCw7ioXy8oytTFc NZFscB8bQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gX0W5-00085H-6f; Wed, 12 Dec 2018 09:09:17 +0000 Date: Wed, 12 Dec 2018 01:09:17 -0800 From: Christoph Hellwig To: Tomasz Figa Cc: Christoph Hellwig , Laurent Pinchart , "Matwey V. Kornilov" , Linux Media Mailing List , Linux Kernel Mailing List , "Matwey V. Kornilov" , Alan Stern , Ezequiel Garcia , hdegoede@redhat.com, Hans Verkuil , Mauro Carvalho Chehab , rostedt@goodmis.org, mingo@redhat.com, Mike Isely , Bhumika Goyal , Colin King , Kieran Bingham , keiichiw@chromium.org Subject: Re: [PATCH v5 2/2] media: usb: pwc: Don't use coherent DMA buffers for ISO transfer Message-ID: <20181212090917.GA30598@infradead.org> References: <20180821170629.18408-1-matwey@sai.msu.ru> <20180821170629.18408-3-matwey@sai.msu.ru> <2213616.rQm4DhIJ7U@avalon> <20181207152502.GA30455@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Wed, Dec 12, 2018 at 05:57:02PM +0900, Tomasz Figa wrote: > How about dma_sync_sg_*()? I'd expect some drivers to export/import > such memory via sg, since that's the typical way of describing memory > in DMA-buf. The way it is implemented dma_sync_sg_* would just work, however there really should be no need to have sglists for buffers created by this API. > Sounds good to me. Thanks for working on this. I'd be happy to be on > CC and help with review when you post the patches later. The patches were already posted here: https://lists.linuxfoundation.org/pipermail/iommu/2018-December/031982.html