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 | 1 +
arch/arm64/include/uapi/asm/kvm.h | 4 ++++
arch/arm64/kvm/hypercalls.c | 24 ++++++++++++++++++++++++
arch/arm64/kvm/pvtime.c | 3 +++
include/kvm/arm_hypercalls.h | 3 +++
5 files changed, 35 insertions(+)
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 1546a2f973ef..e8e540bd1fe5 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -113,6 +113,7 @@ struct hvc_reg_desc {
bool fw_reg_bmap_enabled;
struct hvc_fw_reg_bmap hvc_std_bmap;
+ struct hvc_fw_reg_bmap hvc_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 d6e099ed14ef..5890cbcd6385 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -285,6 +285,10 @@ struct kvm_arm_copy_mte_tags {
#define KVM_REG_ARM_STD_BIT_TRNG_V1_0 BIT(0)
#define KVM_REG_ARM_STD_BMAP_BIT_MAX 0 /* Last valid bit */
+#define KVM_REG_ARM_STD_HYP_BMAP KVM_REG_ARM_FW_REG(4)
+#define KVM_REG_ARM_STD_HYP_BIT_PV_TIME BIT(0)
+#define KVM_REG_ARM_STD_HYP_BMAP_BIT_MAX 0 /* Last valid bit */
+
/* SVE registers */
#define KVM_REG_ARM64_SVE (0x15 << KVM_REG_ARM_COPROC_SHIFT)
diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
index f5df7bc61146..b3320adc068c 100644
--- a/arch/arm64/kvm/hypercalls.c
+++ b/arch/arm64/kvm/hypercalls.c
@@ -84,6 +84,10 @@ bool kvm_hvc_call_supported(struct kvm_vcpu *vcpu, u32 func_id)
case ARM_SMCCC_TRNG_RND64:
return kvm_arm_fw_reg_feat_enabled(&hvc_desc->hvc_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(&hvc_desc->hvc_std_hyp_bmap,
+ KVM_REG_ARM_STD_HYP_BIT_PV_TIME);
default:
/* By default, allow the services that aren't listed here */
return true;
@@ -109,6 +113,9 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
break;
case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:
feature = smccc_get_arg1(vcpu);
+ if (!kvm_hvc_call_supported(vcpu, feature))
+ break;
+
switch (feature) {
case ARM_SMCCC_ARCH_WORKAROUND_1:
switch (arm64_get_spectre_v2_state()) {
@@ -194,6 +201,7 @@ static const u64 fw_reg_ids[] = {
static const u64 fw_reg_bmap_ids[] = {
KVM_REG_ARM_STD_BMAP,
+ KVM_REG_ARM_STD_HYP_BMAP,
};
static void kvm_arm_fw_reg_init_hvc(struct hvc_reg_desc *hvc_desc,
@@ -212,6 +220,8 @@ void kvm_arm_init_hypercalls(struct kvm *kvm)
kvm_arm_fw_reg_init_hvc(hvc_desc, &hvc_desc->hvc_std_bmap,
KVM_REG_ARM_STD_BMAP, ARM_SMCCC_STD_FEATURES);
+ kvm_arm_fw_reg_init_hvc(hvc_desc, &hvc_desc->hvc_std_hyp_bmap,
+ KVM_REG_ARM_STD_HYP_BMAP, ARM_SMCCC_STD_HYP_FEATURES);
}
static void kvm_arm_fw_reg_sanitize(struct hvc_fw_reg_bmap *fw_reg_bmap)
@@ -259,6 +269,7 @@ void kvm_arm_sanitize_fw_regs(struct kvm *kvm)
goto out;
kvm_arm_fw_reg_sanitize(&hvc_desc->hvc_std_bmap);
+ kvm_arm_fw_reg_sanitize(&hvc_desc->hvc_std_hyp_bmap);
out:
spin_unlock(&hvc_desc->lock);
@@ -310,6 +321,9 @@ static int kvm_arm_fw_reg_set_bmap(struct kvm *kvm,
case KVM_REG_ARM_STD_BMAP:
fw_reg_features = ARM_SMCCC_STD_FEATURES;
break;
+ case KVM_REG_ARM_STD_HYP_BMAP:
+ fw_reg_features = ARM_SMCCC_STD_HYP_FEATURES;
+ break;
default:
ret = -EINVAL;
goto out;
@@ -432,6 +446,13 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
if (ret)
return ret;
+ break;
+ case KVM_REG_ARM_STD_HYP_BMAP:
+ ret = kvm_arm_fw_reg_get_bmap(kvm,
+ &hvc_desc->hvc_std_hyp_bmap, &val);
+ if (ret)
+ return ret;
+
break;
default:
return -ENOENT;
@@ -523,6 +544,9 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg)
return 0;
case KVM_REG_ARM_STD_BMAP:
return kvm_arm_fw_reg_set_bmap(kvm, &hvc_desc->hvc_std_bmap, val);
+ case KVM_REG_ARM_STD_HYP_BMAP:
+ return kvm_arm_fw_reg_set_bmap(kvm,
+ &hvc_desc->hvc_std_hyp_bmap, val);
default:
return -ENOENT;
}
diff --git a/arch/arm64/kvm/pvtime.c b/arch/arm64/kvm/pvtime.c
index 78a09f7a6637..4fa436dbd0b7 100644
--- a/arch/arm64/kvm/pvtime.c
+++ b/arch/arm64/kvm/pvtime.c
@@ -37,6 +37,9 @@ long kvm_hypercall_pv_features(struct kvm_vcpu *vcpu)
u32 feature = smccc_get_arg1(vcpu);
long val = SMCCC_RET_NOT_SUPPORTED;
+ if (!kvm_hvc_call_supported(vcpu, feature))
+ return val;
+
switch (feature) {
case ARM_SMCCC_HV_PV_TIME_FEATURES:
case ARM_SMCCC_HV_PV_TIME_ST:
diff --git a/include/kvm/arm_hypercalls.h b/include/kvm/arm_hypercalls.h
index 8c6300d1cbaf..77c30e335f44 100644
--- a/include/kvm/arm_hypercalls.h
+++ b/include/kvm/arm_hypercalls.h
@@ -9,6 +9,9 @@
#define ARM_SMCCC_STD_FEATURES \
GENMASK_ULL(KVM_REG_ARM_STD_BMAP_BIT_MAX, 0)
+#define 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)
--
2.34.0.rc1.387.gb447b232ab-goog
