[PATCH v4 06/13] KVM: arm64: Add standard hypervisor firmware register
Raghavendra Rao Ananta
rananta at google.com
Mon Mar 14 17:23:27 PDT 2022
On Mon, Mar 14, 2022 at 12:45 PM Oliver Upton <oupton at google.com> wrote:
>
> On Thu, Feb 24, 2022 at 05:25:52PM +0000, Raghavendra Rao Ananta wrote:
> > 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.
> >
> > The register is also added to the kvm_arm_vm_scope_fw_regs[] list
> > as it maintains its state per-VM.
> >
> > Signed-off-by: Raghavendra Rao Ananta <rananta at google.com>
> > ---
> > arch/arm64/include/asm/kvm_host.h | 2 ++
> > arch/arm64/include/uapi/asm/kvm.h | 4 ++++
> > arch/arm64/kvm/guest.c | 1 +
> > arch/arm64/kvm/hypercalls.c | 20 +++++++++++++++++++-
> > include/kvm/arm_hypercalls.h | 3 +++
> > 5 files changed, 29 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> > index 1909ced3208f..318148b69279 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_hvc_desc: KVM ARM64 hypercall descriptor
> > *
> > * @hvc_std_bmap: Bitmap of standard secure service calls
> > + * @hvc_std_hyp_bmap: Bitmap of standard hypervisor service calls
> > */
> > struct kvm_hvc_desc {
> > u64 hvc_std_bmap;
> > + u64 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 2decc30d6b84..9a2caead7359 100644
> > --- a/arch/arm64/include/uapi/asm/kvm.h
> > +++ b/arch/arm64/include/uapi/asm/kvm.h
> > @@ -295,6 +295,10 @@ 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_BMAP_REG(1)
> > +#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/guest.c b/arch/arm64/kvm/guest.c
> > index d66e6c742bbe..c42426d6137e 100644
> > --- a/arch/arm64/kvm/guest.c
> > +++ b/arch/arm64/kvm/guest.c
> > @@ -66,6 +66,7 @@ static const u64 kvm_arm_vm_scope_fw_regs[] = {
> > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1,
> > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2,
> > KVM_REG_ARM_STD_BMAP,
> > + KVM_REG_ARM_STD_HYP_BMAP,
> > };
> >
> > /**
> > diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
> > index 48c126c3da72..ebc0cc26cf2e 100644
> > --- a/arch/arm64/kvm/hypercalls.c
> > +++ b/arch/arm64/kvm/hypercalls.c
> > @@ -75,6 +75,10 @@ static 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;
> > @@ -83,6 +87,7 @@ static bool kvm_hvc_call_supported(struct kvm_vcpu *vcpu, u32 func_id)
> >
> > int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
> > {
> > + struct kvm_hvc_desc *hvc_desc = &vcpu->kvm->arch.hvc_desc;
> > u32 func_id = smccc_get_function(vcpu);
> > u64 val[4] = {SMCCC_RET_NOT_SUPPORTED};
> > u32 feature;
> > @@ -134,7 +139,10 @@ 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(
> > + hvc_desc->hvc_std_hyp_bmap,
>
> It is probably OK to keep this parameter on the line above (just stay
> under 100 characters a line).
>
Will rearrange this in the next series. Thanks.
Regards,
Raghavendra
> > + KVM_REG_ARM_STD_HYP_BIT_PV_TIME))
> > + val[0] = SMCCC_RET_SUCCESS;
> > break;
> > }
> > break;
> > @@ -179,6 +187,7 @@ static const u64 kvm_arm_fw_reg_ids[] = {
> > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1,
> > KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2,
> > KVM_REG_ARM_STD_BMAP,
> > + KVM_REG_ARM_STD_HYP_BMAP,
> > };
> >
> > void kvm_arm_init_hypercalls(struct kvm *kvm)
> > @@ -186,6 +195,7 @@ void kvm_arm_init_hypercalls(struct kvm *kvm)
> > struct kvm_hvc_desc *hvc_desc = &kvm->arch.hvc_desc;
> >
> > hvc_desc->hvc_std_bmap = ARM_SMCCC_STD_FEATURES;
> > + hvc_desc->hvc_std_hyp_bmap = ARM_SMCCC_STD_HYP_FEATURES;
> > }
> >
> > int kvm_arm_get_fw_num_regs(struct kvm_vcpu *vcpu)
> > @@ -272,6 +282,9 @@ 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(hvc_desc->hvc_std_bmap);
> > break;
> > + case KVM_REG_ARM_STD_HYP_BMAP:
> > + val = READ_ONCE(hvc_desc->hvc_std_hyp_bmap);
> > + break;
> > default:
> > return -ENOENT;
> > }
> > @@ -294,6 +307,10 @@ static int kvm_arm_set_fw_reg_bmap(struct kvm_vcpu *vcpu, u64 reg_id, u64 val)
> > fw_reg_bmap = &hvc_desc->hvc_std_bmap;
> > fw_reg_features = ARM_SMCCC_STD_FEATURES;
> > break;
> > + case KVM_REG_ARM_STD_HYP_BMAP:
> > + fw_reg_bmap = &hvc_desc->hvc_std_hyp_bmap;
> > + fw_reg_features = ARM_SMCCC_STD_HYP_FEATURES;
> > + break;
> > default:
> > return -ENOENT;
> > }
> > @@ -398,6 +415,7 @@ 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 64d30b452809..a1cb6e839c74 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)
> > --
> > 2.35.1.473.g83b2b277ed-goog
> >
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