On Mon, Oct 04, 2021 at 06:48:40PM +0100, Marc Zyngier wrote:
> Plumb in the hypercall interface to allow a guest to discover,
> enroll, map and unmap MMIO regions.
>
> Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
> ---
> arch/arm64/kvm/hypercalls.c | 28 ++++++++++++++++++++++++++++
> include/linux/arm-smccc.h | 28 ++++++++++++++++++++++++++++
> 2 files changed, 56 insertions(+)
>
> diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
> index 30da78f72b3b..c39aab55ecae 100644
> --- a/arch/arm64/kvm/hypercalls.c
> +++ b/arch/arm64/kvm/hypercalls.c
> @@ -5,6 +5,7 @@
> #include <linux/kvm_host.h>
>
> #include <asm/kvm_emulate.h>
> +#include <asm/kvm_mmu.h>
>
> #include <kvm/arm_hypercalls.h>
> #include <kvm/arm_psci.h>
> @@ -129,10 +130,37 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu)
> case ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID:
> val[0] = BIT(ARM_SMCCC_KVM_FUNC_FEATURES);
> val[0] |= BIT(ARM_SMCCC_KVM_FUNC_PTP);
> + /* Only advertise MMIO guard to 64bit guests */
> + if (!vcpu_mode_is_32bit(vcpu)) {
> + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_MMIO_GUARD_INFO);
> + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_MMIO_GUARD_ENROLL);
> + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_MMIO_GUARD_MAP);
> + val[0] |= BIT(ARM_SMCCC_KVM_FUNC_MMIO_GUARD_UNMAP);
> + }
> break;
> case ARM_SMCCC_VENDOR_HYP_KVM_PTP_FUNC_ID:
> kvm_ptp_get_time(vcpu, val);
> break;
> + case ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_INFO_FUNC_ID:
> + if (!vcpu_mode_is_32bit(vcpu))
> + val[0] = PAGE_SIZE;
> + break;
> + case ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_ENROLL_FUNC_ID:
> + if (!vcpu_mode_is_32bit(vcpu)) {
> + set_bit(KVM_ARCH_FLAG_MMIO_GUARD, &vcpu->kvm->arch.flags);
> + val[0] = SMCCC_RET_SUCCESS;
> + }
> + break;
> + case ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_MAP_FUNC_ID:
> + if (!vcpu_mode_is_32bit(vcpu) &&
> + kvm_install_ioguard_page(vcpu, vcpu_get_reg(vcpu, 1)))
> + val[0] = SMCCC_RET_SUCCESS;
> + break;
> + case ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_UNMAP_FUNC_ID:
> + if (!vcpu_mode_is_32bit(vcpu) &&
> + kvm_remove_ioguard_page(vcpu, vcpu_get_reg(vcpu, 1)))
> + val[0] = SMCCC_RET_SUCCESS;
> + break;
Since these are all ARM_SMCCC_SMC_64 calls, can we do some sort of
refactoring first, similar to Oliver's "KVM: arm64: Clean up SMC64 PSCI
filtering for AArch32 guests", which would avoid the need for all the
!vcpu_mode_is_32bit's?
> case ARM_SMCCC_TRNG_VERSION:
> case ARM_SMCCC_TRNG_FEATURES:
> case ARM_SMCCC_TRNG_GET_UUID:
> diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h
> index 7d1cabe15262..4aab2078d8d3 100644
> --- a/include/linux/arm-smccc.h
> +++ b/include/linux/arm-smccc.h
> @@ -107,6 +107,10 @@
> /* KVM "vendor specific" services */
> #define ARM_SMCCC_KVM_FUNC_FEATURES 0
> #define ARM_SMCCC_KVM_FUNC_PTP 1
> +#define ARM_SMCCC_KVM_FUNC_MMIO_GUARD_INFO 2
> +#define ARM_SMCCC_KVM_FUNC_MMIO_GUARD_ENROLL 3
> +#define ARM_SMCCC_KVM_FUNC_MMIO_GUARD_MAP 4
> +#define ARM_SMCCC_KVM_FUNC_MMIO_GUARD_UNMAP 5
> #define ARM_SMCCC_KVM_FUNC_FEATURES_2 127
> #define ARM_SMCCC_KVM_NUM_FUNCS 128
>
> @@ -133,6 +137,30 @@
> #define KVM_PTP_VIRT_COUNTER 0
> #define KVM_PTP_PHYS_COUNTER 1
>
> +#define ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_INFO_FUNC_ID \
> + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
> + ARM_SMCCC_SMC_64, \
> + ARM_SMCCC_OWNER_VENDOR_HYP, \
> + ARM_SMCCC_KVM_FUNC_MMIO_GUARD_INFO)
> +
> +#define ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_ENROLL_FUNC_ID \
> + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
> + ARM_SMCCC_SMC_64, \
> + ARM_SMCCC_OWNER_VENDOR_HYP, \
> + ARM_SMCCC_KVM_FUNC_MMIO_GUARD_ENROLL)
> +
> +#define ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_MAP_FUNC_ID \
> + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
> + ARM_SMCCC_SMC_64, \
> + ARM_SMCCC_OWNER_VENDOR_HYP, \
> + ARM_SMCCC_KVM_FUNC_MMIO_GUARD_MAP)
> +
> +#define ARM_SMCCC_VENDOR_HYP_KVM_MMIO_GUARD_UNMAP_FUNC_ID \
> + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
> + ARM_SMCCC_SMC_64, \
> + ARM_SMCCC_OWNER_VENDOR_HYP, \
> + ARM_SMCCC_KVM_FUNC_MMIO_GUARD_UNMAP)
> +
> /* Paravirtualised time calls (defined by ARM DEN0057A) */
> #define ARM_SMCCC_HV_PV_TIME_FEATURES \
> ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \
> --
> 2.30.2
>
Besides the refactoring suggestion,
Reviewed-by: Andrew Jones <drjones@xxxxxxxxxx>
Thanks,
drew
