Messages in this thread | | | Date | Tue, 31 May 2022 13:03:09 -0300 | From | Jason Gunthorpe <> | Subject | Re: [PATCH v4 1/6] iommu: Add a per domain PASID for DMA API |
| |
On Tue, May 31, 2022 at 08:45:28PM +0800, Baolu Lu wrote:
> My understanding is that device driver owns its PASID policy.
I'm not sure this is actually useful, the core code should provide the allocator as I can't think of any device that actually needs a special allocator.
> If ENQCMD is supported on the device, the PASIDs should be allocated > through ioasid_alloc(). Otherwise, the whole PASID pool is managed > by the device driver.
This is OK only if we know in-advance that the device needs a global PASID. ENQCMD is one reason, maybe there are others down the road.
Better to make this core code policy.
Jason
| |