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1// SPDX-License-Identifier: GPL-2.02/*3 * ucall support. A ucall is a "hypercall to userspace".4 *5 * Copyright (C) 2018, Red Hat, Inc.6 */7#include "kvm_util.h"8 9vm_vaddr_t *ucall_exit_mmio_addr;10 11void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)12{13 vm_vaddr_t mmio_gva = vm_vaddr_unused_gap(vm, vm->page_size, KVM_UTIL_MIN_VADDR);14 15 virt_map(vm, mmio_gva, mmio_gpa, 1);16 17 vm->ucall_mmio_addr = mmio_gpa;18 19 write_guest_global(vm, ucall_exit_mmio_addr, (vm_vaddr_t *)mmio_gva);20}21 22void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)23{24 struct kvm_run *run = vcpu->run;25 26 if (run->exit_reason == KVM_EXIT_MMIO &&27 run->mmio.phys_addr == vcpu->vm->ucall_mmio_addr) {28 TEST_ASSERT(run->mmio.is_write && run->mmio.len == sizeof(uint64_t),29 "Unexpected ucall exit mmio address access");30 return (void *)(*((uint64_t *)run->mmio.data));31 }32 33 return NULL;34}35