Re: [PATCH 1/4] iommu/vt-d: Implement set device pasid op for default domain

From: Baolu Lu
Date: Mon Mar 06 2023 - 21:18:59 EST


On 3/7/23 1:41 AM, Jason Gunthorpe wrote:
On Mon, Mar 06, 2023 at 09:36:26AM -0800, Jacob Pan wrote:

It seems like all this is doing is flushing the PRI queue.
A domain should have a dedicated flag unrelated to the type if it is
using PRI and all PRI using domains should have the PRI queue flushed
here, using the same code as flushing the PRI for a RID attachment.
Yes, or if the teardown op is domain-specific, then it works too?
That could only sense if we end up creating a PRI domain type too..

Right now PRI is messy because it doesn't really work with unmanaged
domains and that is something that will have to get fixed sort of
soonish

Once PRI is a proper thing then "SVA" is just a PRI domain that has a
non-managed from-the-mm page table pointer.

Most of the driver code marked svm should entirely disappear.

Agreed.

There is also another code consolidation we discussed earlier, that is
moving mmu_notifier_register/unregister to drivers/iommu/iommu-sva.c.
It's common for all SVA-capable iommu drivers.

With PRI domain and mm_notifier addressed, we could safely remove the
switch here. SVA domain will be nothing special. :-)

Best regards,
baolu