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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 653ACC87FC9 for ; Wed, 30 Jul 2025 09:32:23 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9C13910E0C9; Wed, 30 Jul 2025 09:32:22 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="re3qBfXG"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6C51510E0C9 for ; Wed, 30 Jul 2025 09:32:21 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 1CC2445B43; Wed, 30 Jul 2025 09:32:21 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3B5ABC4CEE7; Wed, 30 Jul 2025 09:32:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1753867941; bh=4W4puONHgBcGHwoNV0CY3xma0bboz0RMz11XR/y9JNQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=re3qBfXG4XyZtA/RqPxafo444qv+5COTZZvAJcsIAudJvNJ5GRUrGxzmLMht7qn04 hwCyO3Hzt2ruEpZEzwjjG5TqM57jCt7NS/wTLq9A4i30flu1luxSTT3gmO7ssNsvS2 Lb5pXFUz6XiBnwlYG8HhanlHIjmJFWfrePje/Dln8nbnfZZITOpG3X+Mc4VYGCgMtY LtRFBtuou9BEeShW+H/gLAcqTOk0FFSJQaVIa0Z6ohVZeUE9/L2qylX3UiuRgQ91sw bEWg/OKcbPZyTRB/9hC19ZqDyhbFiEikEPzuwYdJ2SVd4jtrfVeKeJap5nBj7dN4c4 1MrJJzfkPtKTQ== Date: Wed, 30 Jul 2025 12:32:15 +0300 From: Leon Romanovsky To: Jason Gunthorpe Cc: Robin Murphy , Alex Williamson , Christoph Hellwig , Andrew Morton , Bjorn Helgaas , Christian =?iso-8859-1?Q?K=F6nig?= , dri-devel@lists.freedesktop.org, iommu@lists.linux.dev, Jens Axboe , =?iso-8859-1?B?Suly9G1l?= Glisse , Joerg Roedel , kvm@vger.kernel.org, linaro-mm-sig@lists.linaro.org, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linux-pci@vger.kernel.org, Logan Gunthorpe , Marek Szyprowski , Sumit Semwal , Vivek Kasireddy , Will Deacon Subject: Re: [PATCH 10/10] vfio/pci: Add dma-buf export support for MMIO regions Message-ID: <20250730093215.GP402218@unreal> References: <8f912671-f1d9-4f73-9c1d-e39938bfc09f@arm.com> <20250729201351.GA82395@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250729201351.GA82395@nvidia.com> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, Jul 29, 2025 at 05:13:51PM -0300, Jason Gunthorpe wrote: > On Tue, Jul 29, 2025 at 08:44:21PM +0100, Robin Murphy wrote: > > > In this case with just one single > > contiguous mapping, it is clearly objectively worse to have to bounce in and > > out of the IOMMU layer 3 separate times and store a dma_map_state, > > The non-contiguous mappings are comming back, it was in earlier drafts > of this. Regardless, the point is to show how to use the general API > that we would want to bring into the DRM drivers that don't have > contiguity even though VFIO is a bit special. Yes, we will see comeback of DMA ranges in v2. Thanks