Introduce the firmware register to hold the standard hypervisor
service calls (owner value 5) as a bitmap. The bitmap represents
the features that'll be enabled for the guest, as configured by
the user-space. Currently, this includes support only for
Paravirtualized time, represented by bit-0.
Signed-off-by: Raghavendra Rao Ananta <rananta@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 2 ++
arch/arm64/include/uapi/asm/kvm.h | 3 +++
arch/arm64/kvm/hypercalls.c | 21 ++++++++++++++++++---
include/kvm/arm_hypercalls.h | 4 ++++
4 files changed, 27 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 6e663383d7b4..20165242ebd9 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -105,9 +105,11 @@ struct kvm_arch_memory_slot {
* struct kvm_smccc_features: Descriptor the hypercall services exposed to the guests
*
* @std_bmap: Bitmap of standard secure service calls
+ * @std_hyp_bmap: Bitmap of standard hypervisor service calls
*/
struct kvm_smccc_features {
u64 std_bmap;
+ u64 std_hyp_bmap;
};
struct kvm_arch {
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 56e4bc58a355..67353bf4e69d 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -341,6 +341,9 @@ struct kvm_arm_copy_mte_tags {
#define KVM_REG_ARM_STD_BMAP KVM_REG_ARM_FW_FEAT_BMAP_REG(0)
#define KVM_REG_ARM_STD_BIT_TRNG_V1_0 BIT(0)
+#define KVM_REG_ARM_STD_HYP_BMAP KVM_REG_ARM_FW_FEAT_BMAP_REG(1)
+#define KVM_REG_ARM_STD_HYP_BIT_PV_TIME BIT(0)
+
/* Device Control API: ARM VGIC */
#define KVM_DEV_ARM_VGIC_GRP_ADDR 0
#define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1
diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
index cf04b5ee5f56..64ae6c7e7145 100644
--- a/arch/arm64/kvm/hypercalls.c
+++ b/arch/arm64/kvm/hypercalls.c
@@ -65,8 +65,6 @@ static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val)
static const u32 hvc_func_default_allowed_list[] = {
ARM_SMCCC_VERSION_FUNC_ID,
ARM_SMCCC_ARCH_FEATURES_FUNC_ID,
- ARM_SMCCC_HV_PV_TIME_FEATURES,
- ARM_SMCCC_HV_PV_TIME_ST,
ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID,
ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID,
ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID,
@@ -100,6 +98,10 @@ static bool kvm_hvc_call_allowed(struct kvm_vcpu *vcpu, u32 func_id)
case ARM_SMCCC_TRNG_RND64:
return kvm_arm_fw_reg_feat_enabled(smccc_feat->std_bmap,
KVM_REG_ARM_STD_BIT_TRNG_V1_0);
+ case ARM_SMCCC_HV_PV_TIME_FEATURES:
+ case ARM_SMCCC_HV_PV_TIME_ST:
+ return kvm_arm_fw_reg_feat_enabled(smccc_feat->std_hyp_bmap,
+ KVM_REG_ARM_STD_HYP_BIT_PV_TIME);
default:
return kvm_hvc_call_default_allowed(vcpu, func_id);
}
@@ -107,6 +109,7 @@ static bool kvm_hvc_call_allowed(struct kvm_vcpu *vcpu, u32 func_id)
int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
{
+ struct kvm_smccc_features *smccc_feat = &vcpu->kvm->arch.smccc_feat;
u32 func_id = smccc_get_function(vcpu);
u64 val[4] = {SMCCC_RET_NOT_SUPPORTED};
u32 feature;
@@ -170,7 +173,9 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
}
break;
case ARM_SMCCC_HV_PV_TIME_FEATURES:
- val[0] = SMCCC_RET_SUCCESS;
+ if (kvm_arm_fw_reg_feat_enabled(smccc_feat->std_hyp_bmap,
+ KVM_REG_ARM_STD_HYP_BIT_PV_TIME))
+ val[0] = SMCCC_RET_SUCCESS;
break;
}
break;
@@ -216,6 +221,7 @@ static const u64 kvm_arm_fw_reg_ids[] = {
KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2,
KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_3,
KVM_REG_ARM_STD_BMAP,
+ KVM_REG_ARM_STD_HYP_BMAP,
};
void kvm_arm_init_hypercalls(struct kvm *kvm)
@@ -223,6 +229,7 @@ void kvm_arm_init_hypercalls(struct kvm *kvm)
struct kvm_smccc_features *smccc_feat = &kvm->arch.smccc_feat;
smccc_feat->std_bmap = KVM_ARM_SMCCC_STD_FEATURES;
+ smccc_feat->std_hyp_bmap = KVM_ARM_SMCCC_STD_HYP_FEATURES;
}
int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
@@ -312,6 +319,9 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
case KVM_REG_ARM_STD_BMAP:
val = READ_ONCE(smccc_feat->std_bmap);
break;
+ case KVM_REG_ARM_STD_HYP_BMAP:
+ val = READ_ONCE(smccc_feat->std_hyp_bmap);
+ break;
default:
return -ENOENT;
}
@@ -334,6 +344,10 @@ static int kvm_arm_set_fw_reg_bmap(struct kvm_vcpu *vcpu, u64 reg_id, u64 val)
fw_reg_bmap = &smccc_feat->std_bmap;
fw_reg_features = KVM_ARM_SMCCC_STD_FEATURES;
break;
+ case KVM_REG_ARM_STD_HYP_BMAP:
+ fw_reg_bmap = &smccc_feat->std_hyp_bmap;
+ fw_reg_features = KVM_ARM_SMCCC_STD_HYP_FEATURES;
+ break;
default:
return -ENOENT;
}
@@ -438,6 +452,7 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return 0;
case KVM_REG_ARM_STD_BMAP:
+ case KVM_REG_ARM_STD_HYP_BMAP:
return kvm_arm_set_fw_reg_bmap(vcpu, reg->id, val);
default:
return -ENOENT;
diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h
index fd3ff350ee9d..b0915d8c5b81 100644
--- a/include/kvm/arm_hypercalls.h
+++ b/include/kvm/arm_hypercalls.h
@@ -8,10 +8,14 @@
/* Last valid bits of the bitmapped firmware registers */
#define KVM_REG_ARM_STD_BMAP_BIT_MAX 0
+#define KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX 0
#define KVM_ARM_SMCCC_STD_FEATURES \
GENMASK_ULL(KVM_REG_ARM_STD_BMAP_BIT_MAX, 0)
+#define KVM_ARM_SMCCC_STD_HYP_FEATURES \
+ GENMASK_ULL(KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX, 0)
+
int kvm_hvc_call_handler(struct kvm_vcpu *vcpu);
static inline u32 smccc_get_function(struct kvm_vcpu *vcpu)
--
2.35.1.1094.g7c7d902a7c-goog
