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;
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
