xref: /openbmc/linux/arch/x86/kernel/cpu/hypervisor.c (revision 0d07cf5e)
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 extern const struct hypervisor_x86 x86_hyper_vmware;
30 extern const struct hypervisor_x86 x86_hyper_ms_hyperv;
31 extern const struct hypervisor_x86 x86_hyper_xen_pv;
32 extern const struct hypervisor_x86 x86_hyper_xen_hvm;
33 extern const struct hypervisor_x86 x86_hyper_kvm;
34 extern const struct hypervisor_x86 x86_hyper_jailhouse;
35 extern const struct hypervisor_x86 x86_hyper_acrn;
36 
37 static const __initconst struct hypervisor_x86 * const hypervisors[] =
38 {
39 #ifdef CONFIG_XEN_PV
40 	&x86_hyper_xen_pv,
41 #endif
42 #ifdef CONFIG_XEN_PVHVM
43 	&x86_hyper_xen_hvm,
44 #endif
45 	&x86_hyper_vmware,
46 	&x86_hyper_ms_hyperv,
47 #ifdef CONFIG_KVM_GUEST
48 	&x86_hyper_kvm,
49 #endif
50 #ifdef CONFIG_JAILHOUSE_GUEST
51 	&x86_hyper_jailhouse,
52 #endif
53 #ifdef CONFIG_ACRN_GUEST
54 	&x86_hyper_acrn,
55 #endif
56 };
57 
58 enum x86_hypervisor_type x86_hyper_type;
59 EXPORT_SYMBOL(x86_hyper_type);
60 
61 static inline const struct hypervisor_x86 * __init
62 detect_hypervisor_vendor(void)
63 {
64 	const struct hypervisor_x86 *h = NULL, * const *p;
65 	uint32_t pri, max_pri = 0;
66 
67 	for (p = hypervisors; p < hypervisors + ARRAY_SIZE(hypervisors); p++) {
68 		pri = (*p)->detect();
69 		if (pri > max_pri) {
70 			max_pri = pri;
71 			h = *p;
72 		}
73 	}
74 
75 	if (h)
76 		pr_info("Hypervisor detected: %s\n", h->name);
77 
78 	return h;
79 }
80 
81 static void __init copy_array(const void *src, void *target, unsigned int size)
82 {
83 	unsigned int i, n = size / sizeof(void *);
84 	const void * const *from = (const void * const *)src;
85 	const void **to = (const void **)target;
86 
87 	for (i = 0; i < n; i++)
88 		if (from[i])
89 			to[i] = from[i];
90 }
91 
92 void __init init_hypervisor_platform(void)
93 {
94 	const struct hypervisor_x86 *h;
95 
96 	h = detect_hypervisor_vendor();
97 
98 	if (!h)
99 		return;
100 
101 	copy_array(&h->init, &x86_init.hyper, sizeof(h->init));
102 	copy_array(&h->runtime, &x86_platform.hyper, sizeof(h->runtime));
103 
104 	x86_hyper_type = h->type;
105 	x86_init.hyper.init_platform();
106 }
107