From 428fd6788d4d0e0d390de9fb4486be3c1187310d Mon Sep 17 00:00:00 2001 From: Raghavendra Rao Ananta Date: Mon, 2 May 2022 23:38:47 +0000 Subject: [PATCH] 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 Reviewed-by: Gavin Shan [maz: tidy-up bitmap values] Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220502233853.1233742-4-rananta@google.com --- arch/arm64/include/asm/kvm_host.h | 2 ++ arch/arm64/include/uapi/asm/kvm.h | 7 +++++++ arch/arm64/kvm/hypercalls.c | 23 ++++++++++++++++++++--- 3 files changed, 29 insertions(+), 3 deletions(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index fef597a..281dfcf 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 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 { diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index b0be5ec..7ff5a2c 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -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 diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 22f3a91..c43f78c 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -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; -- 2.7.4