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Petersen" , "daniel@iogearbox.net" , Christoph Hellwig , Dan Williams , "jack@suse.com" , Leon Romanovsky Subject: Re: [LSF/MM/BPF TOPIC] [LSF/MM/BPF ATTEND] : Two stage IOMMU DMA mapping operations Message-ID: <20240305130331.GA3662014@nvidia.com> References: <97f385db-42c9-4c04-8fba-9b1ba8ffc525@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <97f385db-42c9-4c04-8fba-9b1ba8ffc525@nvidia.com> X-ClientProxiedBy: MN2PR16CA0045.namprd16.prod.outlook.com (2603:10b6:208:234::14) To DM6PR12MB3849.namprd12.prod.outlook.com (2603:10b6:5:1c7::26) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM6PR12MB3849:EE_|IA1PR12MB6283:EE_ X-MS-Office365-Filtering-Correlation-Id: 761a7a9f-e14a-430f-dd32-08dc3d14a901 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM6PR12MB3849.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(376005);DIR:OUT;SFP:1101; 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Allocates IOVA space. > 2. Actually maps DMA pages to that space. > For example, map scatter-gather list: For clarity, this has come out of last years topic on the "physr" - we agreed to a general direction where instead of adding a parallel DMA API surface for a new scatterlist alternative we'd improve the DMA API so callers can efficiently bring their own data structure. https://lore.kernel.org/linux-rdma/Y8v+qVZ8OmodOCQ9@nvidia.com/ Jason