diff options
| -rw-r--r-- | drivers/vfio/vfio_iommu_type1.c | 21 | ||||
| -rw-r--r-- | include/uapi/linux/vfio.h | 5 |
2 files changed, 26 insertions, 0 deletions
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 8c7bb9b..1f90344 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -867,6 +867,23 @@ static void vfio_iommu_type1_release(void *iommu_data) kfree(iommu); } +static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu) +{ + struct vfio_domain *domain; + int ret = 1; + + mutex_lock(&iommu->lock); + list_for_each_entry(domain, &iommu->domain_list, next) { + if (!(domain->prot & IOMMU_CACHE)) { + ret = 0; + break; + } + } + mutex_unlock(&iommu->lock); + + return ret; +} + static long vfio_iommu_type1_ioctl(void *iommu_data, unsigned int cmd, unsigned long arg) { @@ -878,6 +895,10 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, case VFIO_TYPE1_IOMMU: case VFIO_TYPE1v2_IOMMU: return 1; + case VFIO_DMA_CC_IOMMU: + if (!iommu) + return 0; + return vfio_domains_have_iommu_cache(iommu); default: return 0; } diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 460fdf2..cb9023d 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -24,6 +24,11 @@ #define VFIO_TYPE1_IOMMU 1 #define VFIO_SPAPR_TCE_IOMMU 2 #define VFIO_TYPE1v2_IOMMU 3 +/* + * IOMMU enforces DMA cache coherence (ex. PCIe NoSnoop stripping). This + * capability is subject to change as groups are added or removed. + */ +#define VFIO_DMA_CC_IOMMU 4 /* * The IOCTL interface is designed for extensibility by embedding the |
