1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ucall support. A ucall is a "hypercall to userspace".
4  *
5  * Copyright (C) 2021 Western Digital Corporation or its affiliates.
6  */
7 
8 #include <linux/kvm.h>
9 
10 #include "kvm_util.h"
11 #include "processor.h"
12 #include "sbi.h"
13 
ucall_arch_get_ucall(struct kvm_vcpu * vcpu)14 void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)
15 {
16 	struct kvm_run *run = vcpu->run;
17 
18 	if (run->exit_reason == KVM_EXIT_RISCV_SBI &&
19 	    run->riscv_sbi.extension_id == KVM_RISCV_SELFTESTS_SBI_EXT) {
20 		switch (run->riscv_sbi.function_id) {
21 		case KVM_RISCV_SELFTESTS_SBI_UCALL:
22 			return (void *)run->riscv_sbi.args[0];
23 		case KVM_RISCV_SELFTESTS_SBI_UNEXP:
24 			vcpu_dump(stderr, vcpu, 2);
25 			TEST_ASSERT(0, "Unexpected trap taken by guest");
26 			break;
27 		default:
28 			break;
29 		}
30 	}
31 	return NULL;
32 }
33