1 // SPDX-License-Identifier: GPL-2.0
3 * ucall support. A ucall is a "hypercall to userspace".
5 * Copyright (C) 2021 Western Digital Corporation or its affiliates.
11 #include "processor.h"
13 void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)
17 struct sbiret sbi_ecall(int ext, int fid, unsigned long arg0,
18 unsigned long arg1, unsigned long arg2,
19 unsigned long arg3, unsigned long arg4,
22 register uintptr_t a0 asm ("a0") = (uintptr_t)(arg0);
23 register uintptr_t a1 asm ("a1") = (uintptr_t)(arg1);
24 register uintptr_t a2 asm ("a2") = (uintptr_t)(arg2);
25 register uintptr_t a3 asm ("a3") = (uintptr_t)(arg3);
26 register uintptr_t a4 asm ("a4") = (uintptr_t)(arg4);
27 register uintptr_t a5 asm ("a5") = (uintptr_t)(arg5);
28 register uintptr_t a6 asm ("a6") = (uintptr_t)(fid);
29 register uintptr_t a7 asm ("a7") = (uintptr_t)(ext);
34 : "+r" (a0), "+r" (a1)
35 : "r" (a2), "r" (a3), "r" (a4), "r" (a5), "r" (a6), "r" (a7)
43 void ucall_arch_do_ucall(vm_vaddr_t uc)
45 sbi_ecall(KVM_RISCV_SELFTESTS_SBI_EXT,
46 KVM_RISCV_SELFTESTS_SBI_UCALL,
50 void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)
52 struct kvm_run *run = vcpu->run;
54 if (run->exit_reason == KVM_EXIT_RISCV_SBI &&
55 run->riscv_sbi.extension_id == KVM_RISCV_SELFTESTS_SBI_EXT) {
56 switch (run->riscv_sbi.function_id) {
57 case KVM_RISCV_SELFTESTS_SBI_UCALL:
58 return (void *)run->riscv_sbi.args[0];
59 case KVM_RISCV_SELFTESTS_SBI_UNEXP:
60 vcpu_dump(stderr, vcpu, 2);
61 TEST_ASSERT(0, "Unexpected trap taken by guest");