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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?MUHa+37NxYHshW2CgFBL7bTORYnxCKmJ4Gpj5A84Xz6PXWITK7SOr3wOYEUc?= =?us-ascii?Q?632TgHet37FM2p8rZQT7kK1VzwsVbCiRfZYM+Zmk8viqFTIzbZr+ok3j28bw?= =?us-ascii?Q?W+kKTzJQ4P4L6ss8qEARX0l0CL1x27XaNfYL3IU1DAIOk4ojzzYRoynFzkdP?= =?us-ascii?Q?WLK+SBvcv0PEA5hSW7SvN4RLtxziv8g6lq0kW3BdA4QavP6i2/jj4JpVfauE?= =?us-ascii?Q?/GnN+G8LA0H5AtnZGiobrgQZjYfm6K5De0fwkBuZxKl+dF2k+tGY+VxGs1/t?= =?us-ascii?Q?W5tFWoGiw+QZjRTAVZJIQVxjAH7w/+/DAJPEECY2/bYBoTo3Lrq9JIZXXKgB?= =?us-ascii?Q?Y6WVc9PQB5kYpiFaDs4crCNCpaG5QfYfMsRgpv6LhtqXDioOvs/GyrtIucrL?= =?us-ascii?Q?FvI53Jr7N6VqgF7wMHnMYZ5LCfI+qTZqFXGhxHOuNDt2rKrAQPSYr2XC0OPE?= =?us-ascii?Q?QdVNHpdOXk3HqAtQmn7zGKccbNYujv0etpbtURZjzP/rM/4naN0Mnf6u/g/Y?= =?us-ascii?Q?RttE9svX6/YlP22u1PCJox2x7sXla706p3d23Wkdy7TYbIWohFvs8h+Ef8jK?= =?us-ascii?Q?EUzF3S8kAaZqtLpuYtXMaL6Z5A2+XxXoV2ZObaMzIT3cypLxjiSj8bcUwG1D?= =?us-ascii?Q?y7SxdJJeMgLDJftfUn6N9LLi7fSrMELXB7okVjY25b0i56n+X3JSqFKkcBlZ?= =?us-ascii?Q?Qqep420FbTeZH/AtL582DjXL4JSmkEc8tpvcp1XmdtLoubAPcz08a2Gv6Guk?= =?us-ascii?Q?T2djz5CqDfFYld0WdM4MA42reSkW1uXnO0EMb1Z0JvYH4PRu9cU28j8fnWsc?= =?us-ascii?Q?riGgfXsK/b/r1pg7/hrz6WIthNGbqF1kPa7tvZfgQrlAQ0RAxNfgveTmp4oZ?= =?us-ascii?Q?VY/PFPpnBNpaZv7xNzHGyc15qflD8KtqoIss8GyfT2sak3Onzplhq4l9ihD9?= =?us-ascii?Q?Q1xfqx7MGO9CneJMUXlb/BSBI3+dbrx86W8Qtc+civScwaTQGmSIjEqlRkyG?= =?us-ascii?Q?XVnztY0xkqibrzZup0plQvZYa8buN+7ZaLHZlOe054hbr/NqDDjVrdv/Gx40?= =?us-ascii?Q?vZbiE7UsahS7F9qlRIBvqsYXKDyEs74HpZbwNxU3QSblkduJoQR6UtqHkqdj?= =?us-ascii?Q?AghvfG45wjVye2lEft7p5jWtKfpBafDAuVAV0joPkaiEe+diovqvTF82LsRA?= =?us-ascii?Q?famfs19CRtH1Dks0cdQNj5Rkm92Ju/8tQEJxSkgmv13EHkpcaCpm+LLIBwLm?= =?us-ascii?Q?Ixl1W8cx6kwp/+CuDjBebBU1UWERIGJK+6JBz1IOsnWfbcfo0tu/ALTtrhac?= =?us-ascii?Q?weyAGfXqdQAF1dIT3nYb+W95FSd6x7GWECefeJQNo6ht9rB4YtkJ6Z9wApjD?= =?us-ascii?Q?ZAeKCLPGhg+BoXziBM30fhRLJPhEW7TDzbJDbRHi4QSOdFyeGsN9YIR4nLta?= =?us-ascii?Q?P9If8vJTRXDu/7XDhAcA4rbWV9chi6hNosprNzNT3RKtWmXDzyjd1Q9CFPw1?= =?us-ascii?Q?5Qkxg+41FTj8H1hrRHnq6L5D4RvdMD2zUuWLQGrdE1uchvwJPGTlC886VTpI?= =?us-ascii?Q?nuCtWsxZLGX5jqi5Oms=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 1bfd248c-30c1-4162-59f8-08ddcd403102 X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jul 2025 19:02:54.2622 (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: uBVs5CwUSAmFbaf1zeb4wikMR1WlTDRnk4lKj3IIeixv79h+RgRWMppJ2Jn0Gm1a X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ5PPF75EAF8F39 On Thu, Jul 24, 2025 at 10:03:13AM +0200, Christoph Hellwig wrote: > On Wed, Jul 23, 2025 at 04:00:06PM +0300, Leon Romanovsky wrote: > > From: Leon Romanovsky > > > > Export the pci_p2pdma_map_type() function to allow external modules > > and subsystems to determine the appropriate mapping type for P2PDMA > > transfers between a provider and target device. > > External modules have no business doing this. So what's the plan? Today the new DMA API broadly has the pattern: switch (pci_p2pdma_state(p2pdma_state, dev, page)) { [..] if (dma_use_iova(state)) { ret = dma_iova_link(dev, state, paddr, offset, [..] } else { dma_addr = dma_map_page(dev, page, 0, map->dma_entry_size, [..] You can't fully use the new API flow without calling pci_p2pdma_state(), which is also not exported today. Is the idea the full new DMA API flow should not be available to modules? We did export dma_iova_link(). Otherwise, the p2p step needs two functions - a struct page-full and a struct page-less version, and they need to be exported. The names here are not so good, it would be nicer to have them be a dma_* prefixed function since they are used with the other dma_ functions. Jason