Re: [PATCH v5 6/9] iommufd: Fault-capable hwpt attach/detach/replace

From: Jason Gunthorpe
Date: Tue May 07 2024 - 20:18:48 EST


On Tue, Apr 30, 2024 at 10:57:07PM +0800, Lu Baolu wrote:
> diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c
> index 13125c0feecb..6357229bf3b4 100644
> --- a/drivers/iommu/iommufd/fault.c
> +++ b/drivers/iommu/iommufd/fault.c
> @@ -15,6 +15,124 @@
> #include "../iommu-priv.h"
> #include "iommufd_private.h"
>
> +static int iommufd_fault_iopf_enable(struct iommufd_device *idev)
> +{
> + int ret;
> +
> + if (idev->iopf_enabled)
> + return 0;
> +
> + ret = iommu_dev_enable_feature(idev->dev, IOMMU_DEV_FEAT_IOPF);
> + if (ret)
> + return ret;
> +
> + idev->iopf_enabled = true;
> +
> + return 0;
> +}

I would greatly prefer we remove this from the drivers :\ I guess it
is Ok for now

Doesn't this need a counter? We can have many fault capable PASIDs?
That will get changed in the PASID series?

Jason