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R. Silva" , Ankit Agrawal , Yishai Hadas , Shameer Kolothum , Kevin Tian , Alex Williamson , Krishnakant Jaju , Matt Ochs , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, iommu@lists.linux.dev, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, kvm@vger.kernel.org, linux-hardening@vger.kernel.org, Alex Mastro , Nicolin Chen References: <20251111-dmabuf-vfio-v8-0-fd9aa5df478f@nvidia.com> <20251111-dmabuf-vfio-v8-6-fd9aa5df478f@nvidia.com> <8a11b605-6ac7-48ac-8f27-22df7072e4ad@amd.com> <20251119134245.GD18335@unreal> <6714dc49-6b5c-4d58-9a43-95bb95873a97@amd.com> <20251119145007.GJ18335@unreal> <26d7ecab-33ed-4aab-82d5-954b0d1d1718@amd.com> <20251119163326.GL18335@unreal> Content-Language: en-US From: =?UTF-8?Q?Christian_K=C3=B6nig?= In-Reply-To: <20251119163326.GL18335@unreal> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: FR4P281CA0132.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:b9::10) To PH7PR12MB5685.namprd12.prod.outlook.com (2603:10b6:510:13c::22) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR12MB5685:EE_|CH3PR12MB8850:EE_ X-MS-Office365-Filtering-Correlation-Id: 4cfe9733-553b-41e2-48bc-08de2802e1e5 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|7416014|376014; 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We already have overloaded the term *mapping* with something completely different. >>>>> >>>>> This function performs DMA mapping, so what name do you suggest instead of dma_buf_map()? >>>> >>>> Something like dma_buf_phys_vec_to_sg_table(). I'm not good at naming either. >>> >>> Can I call it simply dma_buf_mapping() as I plan to put that function in dma_buf_mapping.c >>> file per-your request. >> >> No, just completely drop the term "mapping" here. This is about phys_vector to sg_table conversion and nothing else. > > In order to progress, I renamed these functions to be > dma_buf_phys_vec_to_sgt() and dma_buf_free_sgt(), and put everything in dma_buf_mapping.c file. Yeah, the problem is I even thought more about it and came to the conclusion that this is still not sufficient for an rb or an Ack-by. A core concept of DMA-buf is that the exporter takes care of all the mappings and not the framework. Calling pci_p2pdma_bus_addr_map(), dma_map_phys() or dma_map_phys() from DMA-buf code is extremely questionable. That should really be inside VFIO and not DMA-buf code, so to move forward I strongly suggest to either move that into VFIO or the DMA API directly. Regards, Christian. > > Thanks