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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?jdNZg78XP2T9TUtHO4FrQOYHXwTm5pXMXy4+gH+6XrSX7+gSRUdR6SOGtYEH?= =?us-ascii?Q?HBth39Oc9aLRJBNWgk7O8lPEICHVy+pfoNIpyct5Rj3WezAlVOXAvl4iRCzg?= =?us-ascii?Q?VRcyxl9TvcvDq4wWiG56ZTJlx7IDlObxlQ9JuyPvdbibioMEpVIfgfJGHkB/?= =?us-ascii?Q?B5MPYLJACoNIJH3MHSn0DW2KwM+6yeEyfC9LQ4PqD9PeN7fmLX3u/JSRbXIy?= =?us-ascii?Q?NAXdRpAs3wuONAvSTzn+75geHNCvqxmuFmZLoEz/AqX61KOtRvg93Ee78uND?= =?us-ascii?Q?peUCkwk8Oy09PptlLWkstUOcVdOS4my9pSfWso3H/0IROqZIFLkKoDoNkwcv?= =?us-ascii?Q?kILYeC7kNf+VH6z19s6jkr1t2zH4PtxftHk+sUqKCeX4wQV7ZJ8w6+ko2CqB?= =?us-ascii?Q?iEXLEDSYPg85+Njc5Kaw6p7ej/9nB5LQvS3L9gSNVGzPX7fiPT0jfn+sbDwA?= =?us-ascii?Q?zDo1NrvIGE8yJgrURQyQGI8NGl/gmac6MSrfKEyE2wYOwuihBg+52zpOsKDT?= =?us-ascii?Q?zVPQGuknFn6xhw0ULIhgilBdsMTevgwlb8qik+1gJ43vwHxDHCa2Anp9iHQk?= =?us-ascii?Q?TJLSt9NQ1qSa8R2ssZqykd9si9z9ihI5/MiAuuMbmYKUqklCS2wrGtcSAl9t?= =?us-ascii?Q?f7B56uwj1x2ObZAI4STPBh9GoCG0cjFA0CDbaCzesWcfTbERSpM84j599A3A?= =?us-ascii?Q?7/pOpboO/5AzqdZXmgN3iusPK4ZsGs3PawOZNUKRjdOoMirfvjsNjGaAu3e9?= =?us-ascii?Q?mHR5nsa+ehX36f5u+5vBZKoaCd7cliPg1DxHMnaRcEKCzF/+WOoA7I23qLG9?= =?us-ascii?Q?WWME2fMxQsO5zwF5c0bzvTXVO6Hi2XAQfd98biDYJK17A7m5+17+VtkU5337?= =?us-ascii?Q?YjFKF/V5Pq6THGrsvVlUSNoNyIG/X0vgCedtyw+iebNuNTKeWWOyklAbORXt?= =?us-ascii?Q?2JUO+pW6trCpPpIAfhnlNn4EQ8nX8WAiUMIdLmvdkP5pQpAQ2ATG30U5vkJI?= =?us-ascii?Q?MhRMHPJ1FVQgx7yYaRYurqh8qUxc8NDRXR1mXSAO19NQo+k9y1rbWR+JlkLG?= =?us-ascii?Q?FuzY4iQ4QiaZwAIKT2jv0ZXztWs+nnlZ2aIG7UdiTK++Sl77Fx1AvE65Amt+?= =?us-ascii?Q?Y1875MWrBCt+Wn7UE95WSo+fXxDYboAE+E8BZ++FSd91hEpKBaTazy5qHd5F?= =?us-ascii?Q?GvYxoLDevzvJgY7AqRGDY6RqRTMaSAgYOTnWAXVJEqiXjStCFQ2xk2mhoZ/9?= =?us-ascii?Q?4O3blNpfVskby8PNMgxF4LDXhmAmGIZ97qQgKAQhEvx9H7K+lpUR9d5i4ctY?= =?us-ascii?Q?UMUIVKh1YqIgWJ7ftzcTNKMbIvuAu44IA5qQLDK357xwY6CzE+ywzliWXGJm?= =?us-ascii?Q?L6KnQLr6kD1VXrLjSmlzT9MhabxD2MryJs7/a9RtUr/RmwVnntoTXxdp1NJG?= =?us-ascii?Q?IZzy0C2fDKu4I01dJA/qvtIZRvPDzy/WptVch3Jg08J+u7E1GsZKopGv3DLM?= =?us-ascii?Q?lCw0VQ+/cSQbw0BhTD4bvNTf8wfDSAMKWNhgcNrXutwByTrAMqSyv26wVxme?= =?us-ascii?Q?1DqU5O6tlVCU/VrZBMg=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: ac16ca3a-0c04-4c85-d3ef-08dde64601de X-MS-Exchange-CrossTenant-AuthSource: CH3PR12MB8659.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Aug 2025 15:17:31.2708 (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: PZwuEXlW337UFGaRmTgrOOZ86hQJ0hssTlhNBI9xQ+44PM8OwEdLJrn8oa/w6/tN X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB9342 On Tue, Aug 19, 2025 at 08:36:53PM +0300, Leon Romanovsky wrote: > From: Leon Romanovsky > > Extend base DMA page API to handle MMIO flow and follow > existing dma_map_resource() implementation to rely on dma_map_direct() > only to take DMA direct path. I would reword this a little bit too dma-mapping: implement DMA_ATTR_MMIO for dma_(un)map_page_attrs() Make dma_map_page_attrs() and dma_map_page_attrs() respect DMA_ATTR_MMIO. DMA_ATR_MMIO makes the functions behave the same as dma_(un)map_resource(): - No swiotlb is possible - Legacy dma_ops arches use ops->map_resource() - No kmsan - No arch_dma_map_phys_direct() The prior patches have made the internl funtions called here support DMA_ATTR_MMIO. This is also preparation for turning dma_map_resource() into an inline calling dma_map_phys(DMA_ATTR_MMIO) to consolidate the flows. > @@ -166,14 +167,25 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, > return DMA_MAPPING_ERROR; > > if (dma_map_direct(dev, ops) || > - arch_dma_map_phys_direct(dev, phys + size)) > + (!is_mmio && arch_dma_map_phys_direct(dev, phys + size))) > addr = dma_direct_map_phys(dev, phys, size, dir, attrs); PPC is the only user of arch_dma_map_phys_direct() and it looks like it should be called on MMIO memory. Seems like another inconsistency with map_resource. I'd leave it like the above though for this series. > else if (use_dma_iommu(dev)) > addr = iommu_dma_map_phys(dev, phys, size, dir, attrs); > - else > + else if (is_mmio) { > + if (!ops->map_resource) > + return DMA_MAPPING_ERROR; Probably written like: if (ops->map_resource) addr = ops->map_resource(dev, phys, size, dir, attrs); else addr = DMA_MAPPING_ERROR; As I think some of the design here is to run the trace even on the failure path? Otherwise looks OK Reviewed-by: Jason Gunthorpe Jason