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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?uiQ2rlnFLT7dJLg9vxrZrNnUHrcNf2Z8aXuh48wc7OxC2k0lh5avwbsdSu2b?= =?us-ascii?Q?/24rxDA4oO5IhJDl5yyEREhUcr5/42dsG63IUuqkyTKCAf37P2b1/IQI+VCW?= =?us-ascii?Q?rXtEJy10fXFELDOt7ed61iINtQJXAv6b+qNMxOQXw7wqieMErwqEjGBXivST?= =?us-ascii?Q?6N55Y9utH9MAjn+aEeU8HAz2F2BQ2e242tCmsahVL2DcEl1X/Vi/fXeefZSy?= =?us-ascii?Q?pSz+GsAnNy1iZES7HEkVmT+CJXChHVnsMgR+VKAmETH6DLLsCOoxgQJgY6yv?= =?us-ascii?Q?YtPF+ggGmqxE0Ej/cltiRW7MIgr0xC1AWrgxChB7cl1VxrmXf1ZF1l22r0IR?= =?us-ascii?Q?8PBeOeTlXSyMmH3b7DSm14M8Is9xsKH55gWlzbfEoCvyZB8myFgrDu15iLhu?= =?us-ascii?Q?rkrZ3Gd51qju3ihZfM462LSCpXQT+dPVKSDpg2roQE8Zl41AOLuwSwLspw5C?= =?us-ascii?Q?T2m0tIUFQU5mJyt6ttLX7XkBR1jVojnCUVerF8yQDIGjo6vLqbsUEaocXjKR?= =?us-ascii?Q?bxfE/KzMM4me2azFZG73dOWa+yDp8JcRzF95Ub5zpM6COABmrxJSxvPkFhnh?= =?us-ascii?Q?WhjAlgOO5ESYqZoieez2XAzU/LMpV5BO5aF0OUoySUu38e/arrX65R+K3WkA?= =?us-ascii?Q?yYxlFo926FcS+Z9dShpFnI15vw29aFo36nXCEUbu6WqT1OJgWsWkf2+LjWEs?= =?us-ascii?Q?6T5wXT7h3d7Eil7k0ycSxrh+MYRF1lMgvM7L5sldfekmS1NouY1+ln5mqSCf?= =?us-ascii?Q?98w4pz9l/gr/IM8vgMnuy0Ft6zaoBsN+H4zETBhjFBgKWoVO1D70PozUbQ6Q?= =?us-ascii?Q?s2GFZBCIDBmJqTgO4zXUtN23dTxtS9KEApHdmknnIfo4kMtBpo8FvSLzwF1o?= =?us-ascii?Q?FBI5ilgZxKZ3HObL6glPzr/tbUqCRpiRU2QgCOTuj+xfMy779y5P0VbyzoJl?= =?us-ascii?Q?c8TkeekH+z9DFATYGG1inxbk3LQ9XbP5Yo5V8hdXEKAwzG5G3cXGW0NaZQMS?= =?us-ascii?Q?59g9zTUZJbNRBmPRcjWVStq3LRsQKlQPssVGhAJCkAra7dHgfRdQsQ4GFSEV?= =?us-ascii?Q?GxboMcvvbk7m8/LEU2AmBxW0HyhSw/yWIOWWFonUX8RqRoNUT5y9Hkic7MNI?= =?us-ascii?Q?alJxcX+hHZuFjNKIQeEmxTn0ussJGSVh5oGY/psic9Pw6hBZdqzsD/HGzwoX?= =?us-ascii?Q?rJDliIbo1Gl2qszjm7+hhipLPt16Wgnr2ShjwogRFivXQCC/CibXliZCqFz6?= =?us-ascii?Q?c6cbo3xjjj4NIL+ffB1VR+chg9D6T8bXs1Sr3W581sVf3k6a49QgJCUpYxH1?= =?us-ascii?Q?JTSL0y+iVn/tygp8VHQPUtjIEYMv7yKYbbhUSVjh9NFybgytcdtaKVXeX1nT?= =?us-ascii?Q?UrRRdmqjTuVP8u5X/llT+p+rPQo9x6WyQs50Xd4PNlJhSiK46qEaZ/ZsQRdt?= =?us-ascii?Q?WzHIjdT3OzL+16T+cNNpBuw4UQqn3ghqbQ3RV1N+ZxFRMomUr/hP/8KfS3R2?= =?us-ascii?Q?5cW5FTO1IyikRlSU+wXSuFO/ryXyjnOlO8DVDnjgPSasL0/L9QKwKZSHRJda?= =?us-ascii?Q?b+ff1pJxjzusL9paLPM=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f5e512f2-1f99-4108-b6b3-08ddcd40857c X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jul 2025 19:05:15.9272 (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: DNBLRbleK40FGh2k8TFQC8W8ccHWZ0ii31199y9cf0Pk4w+l1bvxqaYV40vAkEk4 X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ5PPF75EAF8F39 On Fri, Jul 25, 2025 at 10:30:46AM -0600, Logan Gunthorpe wrote: > > > On 2025-07-24 02:13, Leon Romanovsky wrote: > > 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. > > > > VFIO PCI code is built as module. There is no way to access PCI p2p code > > without exporting functions in it. > > The solution that would make more sense to me would be for either > dma_iova_try_alloc() or another helper in dma-iommu.c to handle the > P2PDMA case. This has nothing to do with dma-iommu.c, the decisions here still need to be made even if dma-iommu.c is not compiled in. It could be exported from the main dma code, but I think it would just be a 1 line wrapper around the existing function? I'd rather rename the functions and leave them in the p2pdma.c files... Jason