Add IOMMU_DOMAIN_EXTERNAL for externally managed domains that move or attach devices to another VM address space provisioned by an external owner, such as a type 1 hypervisor.
This is not a paging domain and is not sysfs-selectable as a default domain type. It requires external owner context, such as a vIOMMU. PV IOMMU drivers are expected to use it when moving a device to a guest VM with an already-created S2 IOPT. Assisted-by: GPT-5.6 Sol Signed-off-by: Jacob Pan <[email protected]> --- drivers/iommu/iommu.c | 2 ++ include/linux/iommu.h | 9 +++++++++ 2 files changed, 11 insertions(+) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index cd1bca7ede9a..d0bd3ef00379 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -220,6 +220,8 @@ static const char *iommu_domain_type_str(unsigned int t) return "Translated"; case IOMMU_DOMAIN_PLATFORM: return "Platform"; + case IOMMU_DOMAIN_EXTERNAL: + return "External"; default: return "Unknown"; } diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ac43b8b93f14..ede77b90f0fd 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -188,6 +188,7 @@ enum iommu_domain_cookie_type { #define __IOMMU_DOMAIN_NESTED (1U << 6) /* User-managed address space nested on a stage-2 translation */ +#define __IOMMU_DOMAIN_EXTERNAL (1U << 7) /* Externally managed translation */ #define IOMMU_DOMAIN_ALLOC_FLAGS ~__IOMMU_DOMAIN_DMA_FQ /* @@ -207,6 +208,13 @@ enum iommu_domain_cookie_type { * represented by mm_struct's. * IOMMU_DOMAIN_PLATFORM - Legacy domain for drivers that do their own * dma_api stuff. Do not use in new drivers. + * IOMMU_DOMAIN_EXTERNAL - Externally managed domain for moving/attaching + * devices to another VM address space + * provisioned by the external owner, such as + * a type 1 hypervisor. This is not a + * sysfs-selectable default domain type; it + * requires external owner context such as a + * vIOMMU. */ #define IOMMU_DOMAIN_BLOCKED (0U) #define IOMMU_DOMAIN_IDENTITY (__IOMMU_DOMAIN_PT) @@ -219,6 +227,7 @@ enum iommu_domain_cookie_type { #define IOMMU_DOMAIN_SVA (__IOMMU_DOMAIN_SVA) #define IOMMU_DOMAIN_PLATFORM (__IOMMU_DOMAIN_PLATFORM) #define IOMMU_DOMAIN_NESTED (__IOMMU_DOMAIN_NESTED) +#define IOMMU_DOMAIN_EXTERNAL (__IOMMU_DOMAIN_EXTERNAL) struct iommu_domain { unsigned type; -- 2.43.0
