iommu/vt-d: Reserve a domain id for FL and PT modes (3b33d4ab) · Commits · 戴 / test

Vt-d spec rev3.0 (section 6.2.3.1) requires that each pasid entry for first-level or pass-through translation should be programmed with a domain id different from those used for second-level or nested translation. It is recommended that software could use a same domain id for all first-only and pass-through translations. This reserves a domain id for first-level and pass-through translations. Cc: Ashok Raj <ashok.raj@intel.com> Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> Cc: Kevin Tian <kevin.tian@intel.com> Cc: Liu Yi L <yi.l.liu@intel.com> Cc: Sanjay Kumar <sanjay.k.kumar@intel.com> Signed-off-by:

Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by:

Joerg Roedel <jroedel@suse.de>

drivers/iommu/intel-iommu.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -1621,6 +1621,16 @@ static int iommu_init_domains(struct intel_iommu *iommu)
		*/
		set_bit(0, iommu->domain_ids);

		/*
		* Vt-d spec rev3.0 (section 6.2.3.1) requires that each pasid
		* entry for first-level or pass-through translation modes should
		* be programmed with a domain id different from those used for
		* second-level or nested translation. We reserve a domain id for
		* this purpose.
		*/
		if (sm_supported(iommu))
		set_bit(FLPT_DEFAULT_DID, iommu->domain_ids);

		return 0;
		}

drivers/iommu/intel-pasid.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -17,6 +17,12 @@
		#define PDE_PFN_MASK PAGE_MASK
		#define PASID_PDE_SHIFT 6

		/*
		* Domain ID reserved for pasid entries programmed for first-level
		* only and pass-through transfer modes.
		*/
		#define FLPT_DEFAULT_DID 1

		struct pasid_dir_entry {
		u64 val;
		};

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