From: Jason Gunthorpe jgg@nvidia.com Sent: Wednesday, September 20, 2023 9:05 PM
On Wed, Sep 20, 2023 at 01:28:41PM +0800, Baolu Lu wrote:
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 5db283c17e0d..491bcde1ff96 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4074,6 +4074,25 @@ static struct iommu_domain
*intel_iommu_domain_alloc(unsigned type)
return NULL; } +static struct iommu_domain * +intel_iommu_domain_alloc_user(struct device *dev, u32 flags) +{
- struct iommu_domain *domain;
- struct intel_iommu *iommu;
- iommu = device_to_iommu(dev, NULL, NULL);
- if (!iommu)
return ERR_PTR(-ENODEV);- if ((flags & IOMMU_HWPT_ALLOC_NEST_PARENT) && !ecap_nest(iommu-
ecap))
return ERR_PTR(-EOPNOTSUPP);There is a check missing for supported flags
if (flags & (~IOMMU_HWPT_ALLOC_NEST_PARENT)) return ERR_PTR(-EOPNOTSUPP);
Well, the iommufd has such check. But I also noticed your another reply to Weijiang. So your preference is to do the flags validation in iommu driver instead of iommufd. Isn't it?
- domain = iommu_domain_alloc(dev->bus);
No need to bounce between core and driver. Just,
intel_iommu_domain_alloc(IOMMU_DOMAIN_UNMANAGED);
and fully initialize it before return.
If you are going to do that then intel_iommu_domain_alloc() should fully initialize the domain, not here.
I've also considered what Baolu described, but it requires to do some extra initialization which is duplicated with iommu_domain_alloc(). So I chose this simple way.
Regards, Yi Liu