int kvm_riscv_vcpu_sbi_ecall()

in kvm/vcpu_sbi.c [114:170]

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

int kvm_riscv_vcpu_sbi_ecall(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
	int ret = 1;
	bool next_sepc = true;
	bool userspace_exit = false;
	struct kvm_cpu_context *cp = &vcpu->arch.guest_context;
	const struct kvm_vcpu_sbi_extension *sbi_ext;
	struct kvm_cpu_trap utrap = { 0 };
	unsigned long out_val = 0;
	bool ext_is_v01 = false;

	sbi_ext = kvm_vcpu_sbi_find_ext(cp->a7);
	if (sbi_ext && sbi_ext->handler) {
#ifdef CONFIG_RISCV_SBI_V01
		if (cp->a7 >= SBI_EXT_0_1_SET_TIMER &&
		    cp->a7 <= SBI_EXT_0_1_SHUTDOWN)
			ext_is_v01 = true;
#endif
		ret = sbi_ext->handler(vcpu, run, &out_val, &utrap, &userspace_exit);
	} else {
		/* Return error for unsupported SBI calls */
		cp->a0 = SBI_ERR_NOT_SUPPORTED;
		goto ecall_done;
	}

	/* Handle special error cases i.e trap, exit or userspace forward */
	if (utrap.scause) {
		/* No need to increment sepc or exit ioctl loop */
		ret = 1;
		utrap.sepc = cp->sepc;
		kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
		next_sepc = false;
		goto ecall_done;
	}

	/* Exit ioctl loop or Propagate the error code the guest */
	if (userspace_exit) {
		next_sepc = false;
		ret = 0;
	} else {
		/**
		 * SBI extension handler always returns an Linux error code. Convert
		 * it to the SBI specific error code that can be propagated the SBI
		 * caller.
		 */
		ret = kvm_linux_err_map_sbi(ret);
		cp->a0 = ret;
		ret = 1;
	}
ecall_done:
	if (next_sepc)
		cp->sepc += 4;
	if (!ext_is_v01)
		cp->a1 = out_val;

	return ret;
}