diff options
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 15 | ||||
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 13 | ||||
| -rw-r--r-- | drivers/iommu/intel/iommu.c | 5 | ||||
| -rw-r--r-- | include/linux/dma-iommu.h | 2 |
4 files changed, 24 insertions, 11 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 04545725f187..835f810f2f26 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -1869,13 +1869,6 @@ bypassed by not enabling DMAR with this option. In this case, gfx device will use physical address for DMA. - forcedac [X86-64] - With this option iommu will not optimize to look - for io virtual address below 32-bit forcing dual - address cycle on pci bus for cards supporting greater - than 32-bit addressing. The default is to look - for translation below 32-bit and if not available - then look in the higher range. strict [Default Off] With this option on every unmap_single operation will result in a hardware IOTLB flush operation as opposed @@ -1964,6 +1957,14 @@ nobypass [PPC/POWERNV] Disable IOMMU bypass, using IOMMU for PCI devices. + iommu.forcedac= [ARM64, X86] Control IOVA allocation for PCI devices. + Format: { "0" | "1" } + 0 - Try to allocate a 32-bit DMA address first, before + falling back to the full range if needed. + 1 - Allocate directly from the full usable range, + forcing Dual Address Cycle for PCI cards supporting + greater than 32-bit addressing. + iommu.strict= [ARM64] Configure TLB invalidation behaviour Format: { "0" | "1" } 0 - Lazy mode. diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index af765c813cc8..fdd095e1fa52 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -52,6 +52,17 @@ struct iommu_dma_cookie { }; static DEFINE_STATIC_KEY_FALSE(iommu_deferred_attach_enabled); +bool iommu_dma_forcedac __read_mostly; + +static int __init iommu_dma_forcedac_setup(char *str) +{ + int ret = kstrtobool(str, &iommu_dma_forcedac); + + if (!ret && iommu_dma_forcedac) + pr_info("Forcing DAC for PCI devices\n"); + return ret; +} +early_param("iommu.forcedac", iommu_dma_forcedac_setup); void iommu_dma_free_cpu_cached_iovas(unsigned int cpu, struct iommu_domain *domain) @@ -444,7 +455,7 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain, dma_limit = min(dma_limit, (u64)domain->geometry.aperture_end); /* Try to get PCI devices a SAC address */ - if (dma_limit > DMA_BIT_MASK(32) && dev_is_pci(dev)) + if (dma_limit > DMA_BIT_MASK(32) && !iommu_dma_forcedac && dev_is_pci(dev)) iova = alloc_iova_fast(iovad, iova_len, DMA_BIT_MASK(32) >> shift, false); diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index ee0932307d64..1c32522220bc 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -360,7 +360,6 @@ int intel_iommu_enabled = 0; EXPORT_SYMBOL_GPL(intel_iommu_enabled); static int dmar_map_gfx = 1; -static int dmar_forcedac; static int intel_iommu_strict; static int intel_iommu_superpage = 1; static int iommu_identity_mapping; @@ -451,8 +450,8 @@ static int __init intel_iommu_setup(char *str) dmar_map_gfx = 0; pr_info("Disable GFX device mapping\n"); } else if (!strncmp(str, "forcedac", 8)) { - pr_info("Forcing DAC for PCI devices\n"); - dmar_forcedac = 1; + pr_warn("intel_iommu=forcedac deprecated; use iommu.forcedac instead\n"); + iommu_dma_forcedac = true; } else if (!strncmp(str, "strict", 6)) { pr_info("Disable batched IOTLB flush\n"); intel_iommu_strict = 1; diff --git a/include/linux/dma-iommu.h b/include/linux/dma-iommu.h index 706b68d1359b..13d1f4c14d7b 100644 --- a/include/linux/dma-iommu.h +++ b/include/linux/dma-iommu.h @@ -40,6 +40,8 @@ void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list); void iommu_dma_free_cpu_cached_iovas(unsigned int cpu, struct iommu_domain *domain); +extern bool iommu_dma_forcedac; + #else /* CONFIG_IOMMU_DMA */ struct iommu_domain; |