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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A0978C433EF for ; Tue, 9 Nov 2021 14:25:38 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (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 5500161053 for ; Tue, 9 Nov 2021 14:25:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 5500161053 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 0D60780CF7; Tue, 9 Nov 2021 14:25:38 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id VboTGU0KemRq; Tue, 9 Nov 2021 14:25:37 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp1.osuosl.org (Postfix) with ESMTPS id 0E4ED80F13; Tue, 9 Nov 2021 14:25:37 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id DCC0EC0012; Tue, 9 Nov 2021 14:25:36 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 25519C000E for ; Tue, 9 Nov 2021 14:25:36 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 05D8D40332 for ; Tue, 9 Nov 2021 14:25:36 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id u5__stszB080 for ; Tue, 9 Nov 2021 14:25:35 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by smtp4.osuosl.org (Postfix) with ESMTPS id 6FD3F400AA for ; Tue, 9 Nov 2021 14:25:35 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 73FF167373; Tue, 9 Nov 2021 15:25:32 +0100 (CET) Date: Tue, 9 Nov 2021 15:25:32 +0100 From: Christoph Hellwig To: Robin Murphy Subject: Re: [PATCH 05/10] dma-direct: factor out a helper for DMA_ATTR_NO_KERNEL_MAPPING allocations Message-ID: <20211109142532.GD23489@lst.de> References: <20211021090611.488281-1-hch@lst.de> <20211021090611.488281-6-hch@lst.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Cc: iommu@lists.linux-foundation.org, Christoph Hellwig , David Rientjes 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 Thu, Nov 04, 2021 at 12:36:16PM +0000, Robin Murphy wrote: >> - *dma_handle = phys_to_dma_direct(dev, page_to_phys(page)); >> - /* return the page pointer as the opaque cookie */ >> - return page; >> - } >> + !force_dma_unencrypted(dev) && !is_swiotlb_for_alloc(dev)) > > Hmm, does force_dma_unencrypted() actually matter if the caller doesn't > want to access the buffer itself? Presumably any subsequent mmap() to > userspace would still do the right thing? Well, force_dma_unencrypted is a bit misnamed I think. It is mostly used to force bounce buffering for protected guest schemes. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu