xref: /linux/tools/testing/selftests/kvm/lib/x86_64/hyperv.c (revision 55d0969c451159cff86949b38c39171cab962069)
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 
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 
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 
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 
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 
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 
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