[PATCH v7 17/22] KVM: arm64: Expose SDEI capbility and service

[Gavin Shan <gshan@redhat.com>]

The SDEI functionality is ready and lets exposes the capability
and service.

  * KVM_CAP_ARM_SDEI

  * KVM_REG_ARM_STD_BIT_SDEI in pseudo-firmware bitmap register
    KVM_REG_ARM_STD_BMAP

  * The events for software signaled one (0x0) and Async PF (0x1)
    are exposed.

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 Documentation/virt/kvm/api.rst            | 11 +++++++++++
 Documentation/virt/kvm/arm/hypercalls.rst |  4 ++++
 arch/arm64/include/asm/kvm_sdei.h         |  2 ++
 arch/arm64/include/uapi/asm/kvm.h         |  1 +
 arch/arm64/kvm/arm.c                      |  1 +
 arch/arm64/kvm/hypercalls.c               |  4 ++++
 include/uapi/linux/kvm.h                  |  1 +
 7 files changed, 24 insertions(+)

diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index 11e00a46c610..011ec0987d71 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -7956,6 +7956,17 @@ should adjust CPUID leaf 0xA to reflect that the PMU is disabled.
 When enabled, KVM will exit to userspace with KVM_EXIT_SYSTEM_EVENT of
 type KVM_SYSTEM_EVENT_SUSPEND to process the guest suspend request.
 
+8.37 KVM_CAP_ARM_SDEI
+---------------------
+
+:Capability: KVM_CAP_ARM_SDEI
+:Architectures: arm64
+:Type: vm
+
+This capability indicates that the SDEI virtual service is supported
+in the host. A VMM can check whether the service is available to enable
+it.
+
 9. Known KVM API problems
 =========================
 
diff --git a/Documentation/virt/kvm/arm/hypercalls.rst b/Documentation/virt/kvm/arm/hypercalls.rst
index 3e23084644ba..8b8159988934 100644
--- a/Documentation/virt/kvm/arm/hypercalls.rst
+++ b/Documentation/virt/kvm/arm/hypercalls.rst
@@ -106,6 +106,10 @@ The pseudo-firmware bitmap register are as follows:
       The bit represents the services offered under v1.0 of ARM True Random
       Number Generator (TRNG) specification, ARM DEN0098.
 
+    Bit-1: KVM_REG_ARM_STD_BIT_SDEI:
+      The bit represents the services offered under v1.1 of ARM Software
+      Delegated Exception Interface (SDEI) specification, ARM DEN0054C.
+
 * KVM_REG_ARM_STD_HYP_BMAP:
     Controls the bitmap of the ARM Standard Hypervisor Service Calls.
 
diff --git a/arch/arm64/include/asm/kvm_sdei.h b/arch/arm64/include/asm/kvm_sdei.h
index a1e960943515..a68d40137a88 100644
--- a/arch/arm64/include/asm/kvm_sdei.h
+++ b/arch/arm64/include/asm/kvm_sdei.h
@@ -15,6 +15,8 @@
 #include <linux/bits.h>
 
 enum {
+	KVM_SDEI_EVENT_SW_SIGNALED = 0,
+	KVM_SDEI_EVENT_ASYNC_PF,
 	KVM_NR_SDEI_EVENTS,
 };
 
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index 3bb134355874..cc3251381960 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -344,6 +344,7 @@ struct kvm_arm_copy_mte_tags {
 
 enum {
 	KVM_REG_ARM_STD_BIT_TRNG_V1_0	= 0,
+	KVM_REG_ARM_STD_BIT_SDEI,
 #ifdef __KERNEL__
 	KVM_REG_ARM_STD_BMAP_BIT_COUNT,
 #endif
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 06cb5e38634e..15ead92ad26d 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -217,6 +217,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 	case KVM_CAP_VCPU_ATTRIBUTES:
 	case KVM_CAP_PTP_KVM:
 	case KVM_CAP_ARM_SYSTEM_SUSPEND:
+	case KVM_CAP_ARM_SDEI:
 		r = 1;
 		break;
 	case KVM_CAP_SET_GUEST_DEBUG2:
diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c
index 88561ac47301..aaa5197ffe83 100644
--- a/arch/arm64/kvm/hypercalls.c
+++ b/arch/arm64/kvm/hypercalls.c
@@ -99,6 +99,10 @@ static bool kvm_hvc_call_allowed(struct kvm_vcpu *vcpu, u32 func)
 	struct kvm_smccc_features *smccc_feat = &vcpu->kvm->arch.smccc_feat;
 
 	switch (func) {
+	case SDEI_1_0_FN(ARM_SMCCC_STANDARD_SDEI_START - 0x20) ...
+	     SDEI_1_0_FN(ARM_SMCCC_STANDARD_SDEI_END - 0x20):
+		return test_bit(KVM_REG_ARM_STD_BIT_SDEI,
+				&smccc_feat->std_bmap);
 	case ARM_SMCCC_TRNG_VERSION:
 	case ARM_SMCCC_TRNG_FEATURES:
 	case ARM_SMCCC_TRNG_GET_UUID:
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 5088bd9f1922..65622bcaeec3 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1157,6 +1157,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_VM_TSC_CONTROL 214
 #define KVM_CAP_SYSTEM_EVENT_DATA 215
 #define KVM_CAP_ARM_SYSTEM_SUSPEND 216
+#define KVM_CAP_ARM_SDEI 217
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
2.23.0