[PATCH v20 26/30] LoongArch: KVM: Implement kvm exception vector

[Tianrui Zhao]

Implement kvm exception vector, using _kvm_fault_tables array to save
the handle function pointer and it is used when vcpu handle exit.

Reviewed-by: Bibo Mao <maobibo@xxxxxxxxxxx>
Signed-off-by: Tianrui Zhao <zhaotianrui@xxxxxxxxxxx>
---
 arch/loongarch/kvm/exit.c | 46 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c
index f9c7951261..a6df2b56ed 100644
--- a/arch/loongarch/kvm/exit.c
+++ b/arch/loongarch/kvm/exit.c
@@ -654,3 +654,49 @@ static int _kvm_handle_fpu_disabled(struct kvm_vcpu *vcpu)
 	kvm_own_fpu(vcpu);
 	return RESUME_GUEST;
 }
+
+/*
+ * Loongarch KVM callback handling for not implemented guest exiting
+ */
+static int _kvm_fault_ni(struct kvm_vcpu *vcpu)
+{
+	unsigned long estat, badv;
+	unsigned int exccode, inst;
+
+	/*
+	 *  Fetch the instruction.
+	 */
+	badv = vcpu->arch.badv;
+	estat = vcpu->arch.host_estat;
+	exccode = (estat & CSR_ESTAT_EXC) >> CSR_ESTAT_EXC_SHIFT;
+	inst = vcpu->arch.badi;
+	kvm_err("Exccode: %d PC=%#lx inst=0x%08x BadVaddr=%#lx estat=%#lx\n",
+			exccode, vcpu->arch.pc, inst, badv, read_gcsr_estat());
+	kvm_arch_vcpu_dump_regs(vcpu);
+	vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+
+	return RESUME_HOST;
+}
+
+static exit_handle_fn _kvm_fault_tables[EXCCODE_INT_START] = {
+	[EXCCODE_TLBL]			= _kvm_handle_read_fault,
+	[EXCCODE_TLBI]			= _kvm_handle_read_fault,
+	[EXCCODE_TLBS]			= _kvm_handle_write_fault,
+	[EXCCODE_TLBM]			= _kvm_handle_write_fault,
+	[EXCCODE_FPDIS]			= _kvm_handle_fpu_disabled,
+	[EXCCODE_GSPR]			= _kvm_handle_gspr,
+};
+
+void _kvm_init_fault(void)
+{
+	int i;
+
+	for (i = 0; i < EXCCODE_INT_START; i++)
+		if (!_kvm_fault_tables[i])
+			_kvm_fault_tables[i] = _kvm_fault_ni;
+}
+
+int _kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)
+{
+	return _kvm_fault_tables[fault](vcpu);
+}
-- 
2.27.0