KVM: arm64: Add standard hypervisor firmware register

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@google.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
[maz: tidy-up bitmap values]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220502233853.1233742-4-rananta@google.com
This commit is contained in:
Raghavendra Rao Ananta 2022-05-02 23:38:47 +00:00 committed by Marc Zyngier
parent 05714cab7d
commit 428fd6788d
3 changed files with 29 additions and 3 deletions

View File

@ -105,9 +105,11 @@ struct kvm_arch_memory_slot {
* struct kvm_smccc_features: Descriptor of 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 {
unsigned long std_bmap;
unsigned long std_hyp_bmap;
};
struct kvm_arch {

View File

@ -345,6 +345,13 @@ enum {
KVM_REG_ARM_STD_BMAP_BIT_COUNT,
};
#define KVM_REG_ARM_STD_HYP_BMAP KVM_REG_ARM_FW_FEAT_BMAP_REG(1)
enum {
KVM_REG_ARM_STD_HYP_BIT_PV_TIME = 0,
KVM_REG_ARM_STD_HYP_BMAP_BIT_COUNT,
};
/* Device Control API: ARM VGIC */
#define KVM_DEV_ARM_VGIC_GRP_ADDR 0
#define KVM_DEV_ARM_VGIC_GRP_DIST_REGS 1

View File

@ -11,6 +11,8 @@
#define KVM_ARM_SMCCC_STD_FEATURES \
GENMASK(KVM_REG_ARM_STD_BMAP_BIT_COUNT - 1, 0)
#define KVM_ARM_SMCCC_STD_HYP_FEATURES \
GENMASK(KVM_REG_ARM_STD_HYP_BMAP_BIT_COUNT - 1, 0)
static void kvm_ptp_get_time(struct kvm_vcpu *vcpu, u64 *val)
{
@ -71,8 +73,6 @@ static bool kvm_hvc_call_default_allowed(u32 func_id)
*/
case ARM_SMCCC_VERSION_FUNC_ID:
case ARM_SMCCC_ARCH_FEATURES_FUNC_ID:
case ARM_SMCCC_HV_PV_TIME_FEATURES:
case ARM_SMCCC_HV_PV_TIME_ST:
case ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID:
case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:
case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:
@ -106,6 +106,10 @@ static bool kvm_hvc_call_allowed(struct kvm_vcpu *vcpu, u32 func_id)
case ARM_SMCCC_TRNG_RND64:
return test_bit(KVM_REG_ARM_STD_BIT_TRNG_V1_0,
&smccc_feat->std_bmap);
case ARM_SMCCC_HV_PV_TIME_FEATURES:
case ARM_SMCCC_HV_PV_TIME_ST:
return test_bit(KVM_REG_ARM_STD_HYP_BIT_PV_TIME,
&smccc_feat->std_hyp_bmap);
default:
return kvm_hvc_call_default_allowed(func_id);
}
@ -113,6 +117,7 @@ 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;
@ -176,7 +181,9 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
}
break;
case ARM_SMCCC_HV_PV_TIME_FEATURES:
val[0] = SMCCC_RET_SUCCESS;
if (test_bit(KVM_REG_ARM_STD_HYP_BIT_PV_TIME,
&smccc_feat->std_hyp_bmap))
val[0] = SMCCC_RET_SUCCESS;
break;
}
break;
@ -222,6 +229,7 @@ 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)
@ -229,6 +237,7 @@ 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)
@ -317,6 +326,9 @@ 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;
}
@ -339,6 +351,10 @@ 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;
}
@ -439,6 +455,7 @@ 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;