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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?fWNdcw9W4sgedUT49hbWKPRTTUXg/xcymYILa5t5DDcl+/9My1s2znn87onm?= =?us-ascii?Q?eUNfqLgOiIka9t9KsT9AHVsuPEdU1+i0e6546ALgkbq2WR9NkKUGwjKXmFRX?= =?us-ascii?Q?B5G14Cv/jgeepwQOCNderAiDXiVGzL2UPtyTZBcGZrwqMRbLNOST7MMLmqb8?= =?us-ascii?Q?iiW6MyGvwzMlxHn73ZxBicUEVCOE6dMJdLlL+yDu49q/kQvxntBwj5XNqxOE?= =?us-ascii?Q?9tdxnt74XkTJAhGLH/J7Uwik408lkp7BvCheu7q6AapEtMMW1VSrogCYUAGZ?= =?us-ascii?Q?725uLeupFB3OYf5QEXMMnjUEFLr6wfSQBAi7O6IzHU8vCKlf7nhmjRd3aATu?= =?us-ascii?Q?CRGZSMfCHmhoATB0J4cw6p17AjTXRRpinlX6B0OwIVtCr/W9z8P2fQCv9v7Q?= =?us-ascii?Q?syR5kNpqsKfXth8uGpUIwCKxhwrnXpZJnJgHYm3YIdlhOodTdhQf7lrn36mZ?= =?us-ascii?Q?uxb7kUu3LcPIaqa8gVdG9Gpj0JOkbqK1M3Uunz5VKkaSaID92KCkiLo9VvHm?= =?us-ascii?Q?4s9RHouaGazcgLe9UTqq7gtOpPBLQ9cQuyc4wUO1ZzfuphvViz/zjESsWx+Q?= =?us-ascii?Q?zFRMGbQ1kosPXy+vWWCVHklLA/L9EgLuvz+iQrb4ypwEFCJhszX65ors/XE6?= =?us-ascii?Q?Id76IdPXNwzdtYVFBSuN8xb3sXBOyYrauS42raAFpcmR9NuMtoGbdxfbTQod?= =?us-ascii?Q?hzbUQwmd/di9n0ISgCctCNvzueEDbvMFz6MoY01hnVl1pPz/MUnM51u7czjz?= =?us-ascii?Q?DCgFXUaeThBkc8Jqte554DQQdLEzJaQxhCJ6PG+F5RbqxUQ/vg+W0Y9M/hZQ?= =?us-ascii?Q?fr0Sxh0QN7MIj09ntFFXB3mtPwXaH7Wl++X98Cu1gpuAb5KLW+u1SoLJ7yk0?= =?us-ascii?Q?W+CXPdwhTv4pKGh5+VnhoBdDn172qAWjrClY4gml3rBhvfECDItM3PuIYfi3?= =?us-ascii?Q?TUv4yQIwRV44+aOald2Js4/lztVSwkfN2Vbqe3qUu/kKpWQin2LStJZkK5vK?= =?us-ascii?Q?2IQJluG3txmfRPAU0C04HYwg1vHZtx3n+dkNQtNp3RQMyrhPNg76Nc5Qla+v?= =?us-ascii?Q?NjjshBo4NRfP+xkDkU+28vLoV+sda7rHjpNFjo6TbGFOlN4mliNajy9mf1I0?= =?us-ascii?Q?VoqbK9M0YLdODjxmWrIha6MNArpNEyvECWmL1UlWb4GY7Z9rWKy+PtZztQEn?= =?us-ascii?Q?Tx6oen/f76Rlcy4TbnLj1aRPvLkMW9AF1LkNeoizENjWohxje/VRpf/Zw+gs?= =?us-ascii?Q?/PFYxYPFjQ1neR9P8nmaX4o+LwrQ886icvRsIWyyM4qPd53QTJ5Imp8Cjqwi?= =?us-ascii?Q?ZfG2FzzgqbYPj44Z27V9t1seT8IgA2rpf25XxgZvbgtNhzHKxBzG6W9n1Y6m?= =?us-ascii?Q?tRh+8x9ZCSHNLNk0i0soIUtKrNdp2rjxB48nmcJWdYuG6h4BWmtfFA+l/FMQ?= =?us-ascii?Q?Av8XF0n69HL+pMmKMJG0xqEo/dvgAg1pIiKOSwOyAxlX3izNhy4hS86tQ4ac?= =?us-ascii?Q?LE+HgB+f2d8M4qUSNPCgq66BIoUSaSpZ0nFcU8+G/IRQuRLYicQCydNlR8yu?= =?us-ascii?Q?4CHim3dllJrwgtANgh3liEdsKimgdeDcu67TNIl3gelA9ubbALnpi/xqwCWt?= =?us-ascii?Q?g3b0gfdZ53ma/KCeJkCqzpF5RDG0YcXAJmEsYZ4zvd8jDwwyRgnUDZCJU2C0?= =?us-ascii?Q?XEtQ+bd9UJN9nZQaHaldNg0Q89WlDdT+YUYZkB9DzOvgIjK3?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 10eef92b-8f3a-45ca-5e4b-08deb0ea4906 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 May 2026 12:22:22.9631 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Ya8KYugCy1i/qJqIcJZb+lBgJonUpGuoXRkPLUnigGwNRPZfFUKcJCV2GqW3xP3a X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS2PR12MB9823 On Wed, May 13, 2026 at 03:53:43PM +0800, Baolu Lu wrote: > > #define IOMMU_IOAS_MAP _IO(IOMMUFD_TYPE, IOMMUFD_CMD_IOAS_MAP) > > +/** > > + * struct iommu_ioas_noiommu_get_pa - ioctl(IOMMU_IOAS_NOIOMMU_GET_PA) > > + * @size: sizeof(struct iommu_ioas_noiommu_get_pa) > > + * @flags: Reserved, must be 0 for now > > + * @ioas_id: IOAS ID to query IOVA to PA mapping from > > + * @__reserved: Must be 0 > > + * @iova: IOVA to query > > + * @out_length: Number of bytes contiguous physical address starting from phys > > Nit: Instead of making this behavior mandatory, would it be valuable to > allocate a bit in @flags to toggle this behavior? For extremely large > mappings (e.g., several GBs of contiguous hugepages), the loop to > determine the contiguous physical addresses might take a long time. A > very long scan could theoretically delay userspace DMA setup. If we are worrying about that then a iova/length pair would be appropriate such that out_len doesn't exceed the length. Right now it stops at the area boundary IIRC. Jason