xref: /linux/arch/x86/kernel/cpu/hypervisor.c (revision 70d1d98934e723b9e463283a542b88f4f009ae82)
1 /*
2  * Common hypervisor code
3  *
4  * Copyright (C) 2008, VMware, Inc.
5  * Author : Alok N Kataria <akataria@vmware.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but
13  * WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
15  * NON INFRINGEMENT.  See the GNU General Public License for more
16  * details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21  *
22  */
23 
24 #include <linux/init.h>
25 #include <linux/export.h>
26 #include <asm/processor.h>
27 #include <asm/hypervisor.h>
28 
29 static const __initconst struct hypervisor_x86 * const hypervisors[] =
30 {
31 #ifdef CONFIG_XEN_PV
32 	&x86_hyper_xen_pv,
33 #endif
34 #ifdef CONFIG_XEN_PVHVM
35 	&x86_hyper_xen_hvm,
36 #endif
37 	&x86_hyper_vmware,
38 	&x86_hyper_ms_hyperv,
39 #ifdef CONFIG_KVM_GUEST
40 	&x86_hyper_kvm,
41 #endif
42 #ifdef CONFIG_JAILHOUSE_GUEST
43 	&x86_hyper_jailhouse,
44 #endif
45 #ifdef CONFIG_ACRN_GUEST
46 	&x86_hyper_acrn,
47 #endif
48 #ifdef CONFIG_BHYVE_GUEST
49 	&x86_hyper_bhyve,
50 #endif
51 };
52 
53 enum x86_hypervisor_type x86_hyper_type;
54 EXPORT_SYMBOL(x86_hyper_type);
55 
56 bool __initdata nopv;
57 static __init int parse_nopv(char *arg)
58 {
59 	nopv = true;
60 	return 0;
61 }
62 early_param("nopv", parse_nopv);
63 
64 static inline const struct hypervisor_x86 * __init
65 detect_hypervisor_vendor(void)
66 {
67 	const struct hypervisor_x86 *h = NULL, * const *p;
68 	uint32_t pri, max_pri = 0;
69 
70 	for (p = hypervisors; p < hypervisors + ARRAY_SIZE(hypervisors); p++) {
71 		if (unlikely(nopv) && !(*p)->ignore_nopv)
72 			continue;
73 
74 		pri = (*p)->detect();
75 		if (pri > max_pri) {
76 			max_pri = pri;
77 			h = *p;
78 		}
79 	}
80 
81 	if (h)
82 		pr_info("Hypervisor detected: %s\n", h->name);
83 
84 	return h;
85 }
86 
87 static void __init copy_array(const void *src, void *target, unsigned int size)
88 {
89 	unsigned int i, n = size / sizeof(void *);
90 	const void * const *from = (const void * const *)src;
91 	const void **to = (const void **)target;
92 
93 	for (i = 0; i < n; i++)
94 		if (from[i])
95 			to[i] = from[i];
96 }
97 
98 void __init init_hypervisor_platform(void)
99 {
100 	const struct hypervisor_x86 *h;
101 
102 	h = detect_hypervisor_vendor();
103 
104 	if (!h)
105 		return;
106 
107 	copy_array(&h->init, &x86_init.hyper, sizeof(h->init));
108 	copy_array(&h->runtime, &x86_platform.hyper, sizeof(h->runtime));
109 
110 	x86_hyper_type = h->type;
111 	x86_init.hyper.init_platform();
112 }
113