tools/testing/selftests/kvm/lib/riscv/ucall.c

   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
  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 }