Re: [PATCH 6/6] iommu/vt-d: Add domain_alloc_user op

On 9/19/23 5:25 PM, Yi Liu wrote:

This adds the domain_alloc_user op implementation. It supports allocating domains to be used as parent under nested translation.

Documentation/process/submitting-patches.rst:

Describe your changes in imperative mood, e.g. "make xyzzy do frotz" instead of "[This patch] makes xyzzy do frotz" or "[I] changed xyzzy to do frotz", as if you are giving orders to the codebase to change its behaviour.

So how about,

Add the domain_alloc_user callback to support allocating domains used as parent under nested translation.

?

Signed-off-by: Yi Liu yi.l.liu@intel.com

drivers/iommu/intel/iommu.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)

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);
  

• 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 (!domain)

• domain = ERR_PTR(-ENOMEM);
  

• return domain;

+}

• static void intel_iommu_domain_free(struct iommu_domain *domain) { if (domain != &si_domain->domain && domain != &blocking_domain)

@@ -4807,6 +4826,7 @@ const struct iommu_ops intel_iommu_ops = { .capable = intel_iommu_capable, .hw_info = intel_iommu_hw_info, .domain_alloc = intel_iommu_domain_alloc,

• .domain_alloc_user = intel_iommu_domain_alloc_user, .probe_device = intel_iommu_probe_device, .probe_finalize = intel_iommu_probe_finalize, .release_device = intel_iommu_release_device,

Best regards, baolu