diff options
Diffstat (limited to 'drivers/thunderbolt/domain.c')
| -rw-r--r-- | drivers/thunderbolt/domain.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c index 93e562f18d40..7416bdbd8576 100644 --- a/drivers/thunderbolt/domain.c +++ b/drivers/thunderbolt/domain.c @@ -7,7 +7,9 @@ */ #include <linux/device.h> +#include <linux/dmar.h> #include <linux/idr.h> +#include <linux/iommu.h> #include <linux/module.h> #include <linux/pm_runtime.h> #include <linux/slab.h> @@ -236,6 +238,20 @@ err_free_str: } static DEVICE_ATTR_RW(boot_acl); +static ssize_t iommu_dma_protection_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + /* + * Kernel DMA protection is a feature where Thunderbolt security is + * handled natively using IOMMU. It is enabled when IOMMU is + * enabled and ACPI DMAR table has DMAR_PLATFORM_OPT_IN set. + */ + return sprintf(buf, "%d\n", + iommu_present(&pci_bus_type) && dmar_platform_optin()); +} +static DEVICE_ATTR_RO(iommu_dma_protection); + static ssize_t security_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -251,6 +267,7 @@ static DEVICE_ATTR_RO(security); static struct attribute *domain_attrs[] = { &dev_attr_boot_acl.attr, + &dev_attr_iommu_dma_protection.attr, &dev_attr_security.attr, NULL, }; |