diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 038e104b922c..840831d5d2ad 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2266,6 +2266,12 @@ static int amd_iommu_def_domain_type(struct device *dev) return 0; } +static bool amd_iommu_enforce_cache_coherency(struct iommu_domain *domain) +{ + /* IOMMU_PTE_FC is always set */ + return true; +} + const struct iommu_ops amd_iommu_ops = { .capable = amd_iommu_capable, .domain_alloc = amd_iommu_domain_alloc, @@ -2288,6 +2294,7 @@ const struct iommu_ops amd_iommu_ops = { .flush_iotlb_all = amd_iommu_flush_iotlb_all, .iotlb_sync = amd_iommu_iotlb_sync, .free = amd_iommu_domain_free, + .enforce_cache_coherency = amd_iommu_enforce_cache_coherency, } }; diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 0edf6084dc14..161199f62270 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4422,7 +4422,8 @@ static int intel_iommu_map(struct iommu_domain *domain, prot |= DMA_PTE_READ; if (iommu_prot & IOMMU_WRITE) prot |= DMA_PTE_WRITE; - if ((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping) + if (((iommu_prot & IOMMU_CACHE) && dmar_domain->iommu_snooping) || + dmar_domain->force_snooping) prot |= DMA_PTE_SNP; max_addr = iova + size; @@ -4545,6 +4546,16 @@ static phys_addr_t intel_iommu_iova_to_phys(struct iommu_domain *domain, return phys; } +static bool intel_iommu_enforce_cache_coherency(struct iommu_domain *domain) +{ + struct dmar_domain *dmar_domain = to_dmar_domain(domain); + + if (!dmar_domain->iommu_snooping) + return false; + dmar_domain->force_snooping = true; + return true; +} + static bool intel_iommu_capable(enum iommu_cap cap) { if (cap == IOMMU_CAP_CACHE_COHERENCY) @@ -4900,6 +4911,7 @@ const struct iommu_ops intel_iommu_ops = { .iotlb_sync = intel_iommu_tlb_sync, .iova_to_phys = intel_iommu_iova_to_phys, .free = intel_iommu_domain_free, + .enforce_cache_coherency = intel_iommu_enforce_cache_coherency, } }; diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index 2f9891cb3d00..4c2baf2446c2 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -540,6 +540,7 @@ struct dmar_domain { u8 has_iotlb_device: 1; u8 iommu_coherency: 1; /* indicate coherency of iommu access */ u8 iommu_snooping: 1; /* indicate snooping control feature */ + u8 force_snooping : 1; /* Create IOPTEs with snoop control */ struct list_head devices; /* all devices' list */ struct iova_domain iovad; /* iova's that belong to this domain */ diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 4123693ae319..c7ad6b10e261 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -274,6 +274,9 @@ struct iommu_ops { * @iotlb_sync: Flush all queued ranges from the hardware TLBs and empty flush * queue * @iova_to_phys: translate iova to physical address + * @enforce_cache_coherency: Prevent any kind of DMA from bypassing IOMMU_CACHE, + * including no-snoop TLPs on PCIe or other platform + * specific mechanisms. * @enable_nesting: Enable nesting * @set_pgtable_quirks: Set io page table quirks (IO_PGTABLE_QUIRK_*) * @free: Release the domain after use. @@ -302,6 +305,7 @@ struct iommu_domain_ops { phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova); + bool (*enforce_cache_coherency)(struct iommu_domain *domain); int (*enable_nesting)(struct iommu_domain *domain); int (*set_pgtable_quirks)(struct iommu_domain *domain, unsigned long quirks);