Commit 3aef9ca6 authored by Jacob Pan's avatar Jacob Pan Committed by Joerg Roedel

iommu/vt-d: Use a helper function to skip agaw for SL

An Intel iommu domain uses 5-level page table by default. If the iommu
that the domain tries to attach supports less page levels, the top level
page tables should be skipped. Add a helper to do this so that it could
be used in other places.
Signed-off-by: default avatarJacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarEric Auger <eric.auger@redhat.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20200516062101.29541-3-baolu.lu@linux.intel.comSigned-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent 3db9983e
......@@ -499,6 +499,25 @@ int intel_pasid_setup_first_level(struct intel_iommu *iommu,
return 0;
}
/*
* Skip top levels of page tables for iommu which has less agaw
* than default. Unnecessary for PT mode.
*/
static inline int iommu_skip_agaw(struct dmar_domain *domain,
struct intel_iommu *iommu,
struct dma_pte **pgd)
{
int agaw;
for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) {
*pgd = phys_to_virt(dma_pte_addr(*pgd));
if (!dma_pte_present(*pgd))
return -EINVAL;
}
return agaw;
}
/*
* Set up the scalable mode pasid entry for second only translation type.
*/
......@@ -522,18 +541,12 @@ int intel_pasid_setup_second_level(struct intel_iommu *iommu,
return -EINVAL;
}
/*
* Skip top levels of page tables for iommu which has less agaw
* than default. Unnecessary for PT mode.
*/
pgd = domain->pgd;
for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) {
pgd = phys_to_virt(dma_pte_addr(pgd));
if (!dma_pte_present(pgd)) {
agaw = iommu_skip_agaw(domain, iommu, &pgd);
if (agaw < 0) {
dev_err(dev, "Invalid domain page table\n");
return -EINVAL;
}
}
pgd_val = virt_to_phys(pgd);
did = domain->iommu_did[iommu->seq_id];
......
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