From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 733841D5AC6; Wed, 30 Jul 2025 09:32:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753867941; cv=none; b=OCL9xLG4stSMrw3wBxnVDZ/UVwopXcDT1TqOOzG3+OScIh3daA4RS/2CdtibhaTtLxlRxt2I+cIuwIlAnrj0L8pTszcjRPCqn3LS393+vW4MSwax+DGI3XmRwZ4A7Q/JDPIRGki8IDujjJg5hXEsRrJ6ZZAct9FBtyccKDHgl1o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753867941; c=relaxed/simple; bh=4W4puONHgBcGHwoNV0CY3xma0bboz0RMz11XR/y9JNQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gxfu9Lc2X1BBXbid2aO32/1hbmawJS8Fv17vl5f5u2d2hcge84XIraU8CHirLywwLbgqHzp1IqUGsmoKxXybA/nqkc+vPnOI1x46w/nvAY57d+KfcwIY8txgPo2jM0TFoFRskLIUiN24E3Ba7nOvzk4FxLmY5d3vI2OkTEwQo1A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=re3qBfXG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="re3qBfXG" 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> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250729201351.GA82395@nvidia.com> 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