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Tsirkin" , Miguel Ojeda , Robin Murphy , rust-for-linux@vger.kernel.org, Sagi Grimberg , Stefano Stabellini , Steven Rostedt , virtualization@lists.linux.dev, Will Deacon , xen-devel@lists.xenproject.org Subject: Re: [PATCH v4 01/16] dma-mapping: introduce new DMA attribute to indicate MMIO memory Message-ID: <20250828130329.GA9469@nvidia.com> References: <08e044a00a872932e106f7e27449a8eab2690dbc.1755624249.git.leon@kernel.org> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <08e044a00a872932e106f7e27449a8eab2690dbc.1755624249.git.leon@kernel.org> X-ClientProxiedBy: YT4PR01CA0331.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:10a::27) To CH3PR12MB8659.namprd12.prod.outlook.com (2603:10b6:610:17c::13) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH3PR12MB8659:EE_|CY1PR12MB9583:EE_ X-MS-Office365-Filtering-Correlation-Id: 2e8ce38d-1495-4e9c-fbd5-08dde633497c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|7416014|1800799024|376014|366016; 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'branching when processing generic containers like bio_vec by the callers' Many of the existing dma_map_resource() users already know the thing is MMIO and don't have branching.. > Signed-off-by: Leon Romanovsky > --- > Documentation/core-api/dma-attributes.rst | 18 ++++++++++++++++++ > include/linux/dma-mapping.h | 20 ++++++++++++++++++++ > include/trace/events/dma.h | 3 ++- > rust/kernel/dma.rs | 3 +++ > 4 files changed, 43 insertions(+), 1 deletion(-) Reviewed-by: Jason Gunthorpe Jason