1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Hyper-V specific functions.
4 *
5 * Copyright (C) 2021, Red Hat Inc.
6 */
7 #include <stdint.h>
8 #include "processor.h"
9 #include "hyperv.h"
10
kvm_get_supported_hv_cpuid(void)11 const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void)
12 {
13 static struct kvm_cpuid2 *cpuid;
14 int kvm_fd;
15
16 if (cpuid)
17 return cpuid;
18
19 cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
20 kvm_fd = open_kvm_dev_path_or_exit();
21
22 kvm_ioctl(kvm_fd, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
23
24 close(kvm_fd);
25 return cpuid;
26 }
27
vcpu_set_hv_cpuid(struct kvm_vcpu * vcpu)28 void vcpu_set_hv_cpuid(struct kvm_vcpu *vcpu)
29 {
30 static struct kvm_cpuid2 *cpuid_full;
31 const struct kvm_cpuid2 *cpuid_sys, *cpuid_hv;
32 int i, nent = 0;
33
34 if (!cpuid_full) {
35 cpuid_sys = kvm_get_supported_cpuid();
36 cpuid_hv = kvm_get_supported_hv_cpuid();
37
38 cpuid_full = allocate_kvm_cpuid2(cpuid_sys->nent + cpuid_hv->nent);
39 if (!cpuid_full) {
40 perror("malloc");
41 abort();
42 }
43
44 /* Need to skip KVM CPUID leaves 0x400000xx */
45 for (i = 0; i < cpuid_sys->nent; i++) {
46 if (cpuid_sys->entries[i].function >= 0x40000000 &&
47 cpuid_sys->entries[i].function < 0x40000100)
48 continue;
49 cpuid_full->entries[nent] = cpuid_sys->entries[i];
50 nent++;
51 }
52
53 memcpy(&cpuid_full->entries[nent], cpuid_hv->entries,
54 cpuid_hv->nent * sizeof(struct kvm_cpuid_entry2));
55 cpuid_full->nent = nent + cpuid_hv->nent;
56 }
57
58 vcpu_init_cpuid(vcpu, cpuid_full);
59 }
60
vcpu_get_supported_hv_cpuid(struct kvm_vcpu * vcpu)61 const struct kvm_cpuid2 *vcpu_get_supported_hv_cpuid(struct kvm_vcpu *vcpu)
62 {
63 struct kvm_cpuid2 *cpuid = allocate_kvm_cpuid2(MAX_NR_CPUID_ENTRIES);
64
65 vcpu_ioctl(vcpu, KVM_GET_SUPPORTED_HV_CPUID, cpuid);
66
67 return cpuid;
68 }
69
kvm_hv_cpu_has(struct kvm_x86_cpu_feature feature)70 bool kvm_hv_cpu_has(struct kvm_x86_cpu_feature feature)
71 {
72 if (!kvm_has_cap(KVM_CAP_SYS_HYPERV_CPUID))
73 return false;
74
75 return kvm_cpuid_has(kvm_get_supported_hv_cpuid(), feature);
76 }
77
vcpu_alloc_hyperv_test_pages(struct kvm_vm * vm,vm_vaddr_t * p_hv_pages_gva)78 struct hyperv_test_pages *vcpu_alloc_hyperv_test_pages(struct kvm_vm *vm,
79 vm_vaddr_t *p_hv_pages_gva)
80 {
81 vm_vaddr_t hv_pages_gva = vm_vaddr_alloc_page(vm);
82 struct hyperv_test_pages *hv = addr_gva2hva(vm, hv_pages_gva);
83
84 /* Setup of a region of guest memory for the VP Assist page. */
85 hv->vp_assist = (void *)vm_vaddr_alloc_page(vm);
86 hv->vp_assist_hva = addr_gva2hva(vm, (uintptr_t)hv->vp_assist);
87 hv->vp_assist_gpa = addr_gva2gpa(vm, (uintptr_t)hv->vp_assist);
88
89 /* Setup of a region of guest memory for the partition assist page. */
90 hv->partition_assist = (void *)vm_vaddr_alloc_page(vm);
91 hv->partition_assist_hva = addr_gva2hva(vm, (uintptr_t)hv->partition_assist);
92 hv->partition_assist_gpa = addr_gva2gpa(vm, (uintptr_t)hv->partition_assist);
93
94 /* Setup of a region of guest memory for the enlightened VMCS. */
95 hv->enlightened_vmcs = (void *)vm_vaddr_alloc_page(vm);
96 hv->enlightened_vmcs_hva = addr_gva2hva(vm, (uintptr_t)hv->enlightened_vmcs);
97 hv->enlightened_vmcs_gpa = addr_gva2gpa(vm, (uintptr_t)hv->enlightened_vmcs);
98
99 *p_hv_pages_gva = hv_pages_gva;
100 return hv;
101 }
102
enable_vp_assist(uint64_t vp_assist_pa,void * vp_assist)103 int enable_vp_assist(uint64_t vp_assist_pa, void *vp_assist)
104 {
105 uint64_t val = (vp_assist_pa & HV_X64_MSR_VP_ASSIST_PAGE_ADDRESS_MASK) |
106 HV_X64_MSR_VP_ASSIST_PAGE_ENABLE;
107
108 wrmsr(HV_X64_MSR_VP_ASSIST_PAGE, val);
109
110 current_vp_assist = vp_assist;
111
112 return 0;
113 }
114