NVIDIA implementation needs to link its Virtual Interface to a VMID, before a device gets attached to the corresponding iommu domain. One way to ensure that is to allocate a VMID from impl side and to pass it down to virtual machine hypervisor so that later it can set it back to passthrough devices' iommu domains calling newly added arm_smmu_set/get_nesting_vmid() functions. This patch adds a pair of helpers to allocate and free VMID in the bitmap. Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 10 ++++++++++ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 +++ 2 files changed, 13 insertions(+) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index c0ae117711fa..497d55ec659b 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2032,6 +2032,16 @@ static void arm_smmu_bitmap_free(unsigned long *map, int idx) clear_bit(idx, map); } +int arm_smmu_vmid_alloc(struct arm_smmu_device *smmu) +{ + return arm_smmu_bitmap_alloc(smmu->vmid_map, smmu->vmid_bits); +} + +void arm_smmu_vmid_free(struct arm_smmu_device *smmu, u16 vmid) +{ + arm_smmu_bitmap_free(smmu->vmid_map, vmid); +} + static void arm_smmu_domain_free(struct iommu_domain *domain) { struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain); diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index ea2c61d52df8..20463d17fd9f 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -749,6 +749,9 @@ bool arm_smmu_free_asid(struct arm_smmu_ctx_desc *cd); int arm_smmu_atc_inv_domain(struct arm_smmu_domain *smmu_domain, int ssid, unsigned long iova, size_t size); +int arm_smmu_vmid_alloc(struct arm_smmu_device *smmu); +void arm_smmu_vmid_free(struct arm_smmu_device *smmu, u16 vmid); + #ifdef CONFIG_ARM_SMMU_V3_SVA bool arm_smmu_sva_supported(struct arm_smmu_device *smmu); bool arm_smmu_master_sva_supported(struct arm_smmu_master *master); -- 2.17.1