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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 1400EC64E7B for ; Tue, 1 Dec 2020 14:49:26 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 380A1204EA for ; Tue, 1 Dec 2020 14:49:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 380A1204EA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id E9A06841B3; Tue, 1 Dec 2020 14:49:24 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id xup-ido_ltma; Tue, 1 Dec 2020 14:49:23 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by fraxinus.osuosl.org (Postfix) with ESMTP id B524481B69; Tue, 1 Dec 2020 14:49:23 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 98AF4C0859; Tue, 1 Dec 2020 14:49:23 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id B94FBC0052 for ; Tue, 1 Dec 2020 14:49:22 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id A630287591 for ; Tue, 1 Dec 2020 14:49:22 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id G5dyvN2eNkXc for ; Tue, 1 Dec 2020 14:49:21 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by hemlock.osuosl.org (Postfix) with ESMTPS id 6732587582 for ; Tue, 1 Dec 2020 14:49:21 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 8C8EB67373; Tue, 1 Dec 2020 15:49:16 +0100 (CET) Date: Tue, 1 Dec 2020 15:49:16 +0100 From: Christoph Hellwig To: Sergey Senozhatsky Subject: Re: [PATCH v3 5/6] media: uvcvideo: Use dma_alloc_noncontiguos API Message-ID: <20201201144916.GA14682@lst.de> References: <20201125221917.150463-1-ribalda@chromium.org> <20201130083410.GD32234@lst.de> <20201201033658.GE3723071@google.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201201033658.GE3723071@google.com> User-Agent: Mutt/1.5.17 (2007-11-01) Cc: Sergey Senozhatsky , Linux Media Mailing List , Linux Doc Mailing List , Linux Kernel Mailing List , IOMMU DRIVERS , Ricardo Ribalda , Mauro Carvalho Chehab , Robin Murphy , Christoph Hellwig X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Tue, Dec 01, 2020 at 12:36:58PM +0900, Sergey Senozhatsky wrote: > Not that I have any sound experience in this area, but the helper > probably won't hurt. Do you also plan to add vmap() to that helper > or dma_alloc_noncontiguous()/sg_alloc_table_from_pages() only? Yes, I think adding the vmap is useful, and it probably makes sense to do that unconditionally. I'd also include the fallback to dma_alloc_pages when the noncontig version isn't supported in the helper. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu