[PATCH 4/6] KVM: PPC: Book3S HV: Add one-reg interface for DEXCR register

[Shivaprasad G Bhat <sbhat@linux.ibm.com>]

The patch adds a one-reg register identifier which can be used to
read and set the DEXCR for the guest during enter/exit with
KVM_REG_PPC_DEXCR. The specific SPR KVM API documentation
too updated.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
---
 Documentation/virt/kvm/api.rst            |    1 +
 arch/powerpc/include/uapi/asm/kvm.h       |    1 +
 arch/powerpc/kvm/book3s_hv.c              |    6 ++++++
 tools/arch/powerpc/include/uapi/asm/kvm.h |    1 +
 4 files changed, 9 insertions(+)

diff --git a/Documentation/virt/kvm/api.rst b/Documentation/virt/kvm/api.rst
index a71d91978d9e..81077c654281 100644
--- a/Documentation/virt/kvm/api.rst
+++ b/Documentation/virt/kvm/api.rst
@@ -2441,6 +2441,7 @@ registers, find a list below:
   PPC     KVM_REG_PPC_PTCR                64
   PPC     KVM_REG_PPC_DAWR1               64
   PPC     KVM_REG_PPC_DAWRX1              64
+  PPC     KVM_REG_PPC_DEXCR               64
   PPC     KVM_REG_PPC_TM_GPR0             64
   ...
   PPC     KVM_REG_PPC_TM_GPR31            64
diff --git a/arch/powerpc/include/uapi/asm/kvm.h b/arch/powerpc/include/uapi/asm/kvm.h
index 1691297a766a..fcb947f65667 100644
--- a/arch/powerpc/include/uapi/asm/kvm.h
+++ b/arch/powerpc/include/uapi/asm/kvm.h
@@ -645,6 +645,7 @@ struct kvm_ppc_cpu_char {
 #define KVM_REG_PPC_SIER3	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc3)
 #define KVM_REG_PPC_DAWR1	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc4)
 #define KVM_REG_PPC_DAWRX1	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc5)
+#define KVM_REG_PPC_DEXCR	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc6)
 
 /* Transactional Memory checkpointed state:
  * This is all GPRs, all VSX regs and a subset of SPRs
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index b576781d58d5..1294c6839d37 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2349,6 +2349,9 @@ static int kvmppc_get_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
 	case KVM_REG_PPC_DAWRX1:
 		*val = get_reg_val(id, kvmppc_get_dawrx1_hv(vcpu));
 		break;
+	case KVM_REG_PPC_DEXCR:
+		*val = get_reg_val(id, kvmppc_get_dexcr_hv(vcpu));
+		break;
 	case KVM_REG_PPC_CIABR:
 		*val = get_reg_val(id, kvmppc_get_ciabr_hv(vcpu));
 		break;
@@ -2592,6 +2595,9 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
 	case KVM_REG_PPC_DAWRX1:
 		kvmppc_set_dawrx1_hv(vcpu, set_reg_val(id, *val) & ~DAWRX_HYP);
 		break;
+	case KVM_REG_PPC_DEXCR:
+		kvmppc_set_dexcr_hv(vcpu, set_reg_val(id, *val));
+		break;
 	case KVM_REG_PPC_CIABR:
 		kvmppc_set_ciabr_hv(vcpu, set_reg_val(id, *val));
 		/* Don't allow setting breakpoints in hypervisor code */
diff --git a/tools/arch/powerpc/include/uapi/asm/kvm.h b/tools/arch/powerpc/include/uapi/asm/kvm.h
index 1691297a766a..fcb947f65667 100644
--- a/tools/arch/powerpc/include/uapi/asm/kvm.h
+++ b/tools/arch/powerpc/include/uapi/asm/kvm.h
@@ -645,6 +645,7 @@ struct kvm_ppc_cpu_char {
 #define KVM_REG_PPC_SIER3	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc3)
 #define KVM_REG_PPC_DAWR1	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc4)
 #define KVM_REG_PPC_DAWRX1	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc5)
+#define KVM_REG_PPC_DEXCR	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xc6)
 
 /* Transactional Memory checkpointed state:
  * This is all GPRs, all VSX regs and a subset of SPRs