int kvm_riscv_vcpu_mmio_return()

in kvm/vcpu_exit.c [601:652]

• 44 lines of code
• 7 McCabe index (conditional complexity)

int kvm_riscv_vcpu_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	u8 data8;
	u16 data16;
	u32 data32;
	u64 data64;
	ulong insn;
	int len, shift;

	if (vcpu->arch.mmio_decode.return_handled)
		return 0;

	vcpu->arch.mmio_decode.return_handled = 1;
	insn = vcpu->arch.mmio_decode.insn;

	if (run->mmio.is_write)
		goto done;

	len = vcpu->arch.mmio_decode.len;
	shift = vcpu->arch.mmio_decode.shift;

	switch (len) {
	case 1:
		data8 = *((u8 *)run->mmio.data);
		SET_RD(insn, &vcpu->arch.guest_context,
			(ulong)data8 << shift >> shift);
		break;
	case 2:
		data16 = *((u16 *)run->mmio.data);
		SET_RD(insn, &vcpu->arch.guest_context,
			(ulong)data16 << shift >> shift);
		break;
	case 4:
		data32 = *((u32 *)run->mmio.data);
		SET_RD(insn, &vcpu->arch.guest_context,
			(ulong)data32 << shift >> shift);
		break;
	case 8:
		data64 = *((u64 *)run->mmio.data);
		SET_RD(insn, &vcpu->arch.guest_context,
			(ulong)data64 << shift >> shift);
		break;
	default:
		return -EOPNOTSUPP;
	}

done:
	/* Move to next instruction */
	vcpu->arch.guest_context.sepc += vcpu->arch.mmio_decode.insn_len;

	return 0;
}