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
29static 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};
49
50enum x86_hypervisor_type x86_hyper_type;
51EXPORT_SYMBOL(x86_hyper_type);
52
53bool __initdata nopv;
54static __init int parse_nopv(char *arg)
55{
56 nopv = true;
57 return 0;
58}
59early_param("nopv", parse_nopv);
60
61static inline const struct hypervisor_x86 * __init
62detect_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 if (unlikely(nopv) && !(*p)->ignore_nopv)
69 continue;
70
71 pri = (*p)->detect();
72 if (pri > max_pri) {
73 max_pri = pri;
74 h = *p;
75 }
76 }
77
78 if (h)
79 pr_info("Hypervisor detected: %s\n", h->name);
80
81 return h;
82}
83
84static void __init copy_array(const void *src, void *target, unsigned int size)
85{
86 unsigned int i, n = size / sizeof(void *);
87 const void * const *from = (const void * const *)src;
88 const void **to = (const void **)target;
89
90 for (i = 0; i < n; i++)
91 if (from[i])
92 to[i] = from[i];
93}
94
95void __init init_hypervisor_platform(void)
96{
97 const struct hypervisor_x86 *h;
98
99 h = detect_hypervisor_vendor();
100
101 if (!h)
102 return;
103
104 copy_array(src: &h->init, target: &x86_init.hyper, size: sizeof(h->init));
105 copy_array(src: &h->runtime, target: &x86_platform.hyper, size: sizeof(h->runtime));
106
107 x86_hyper_type = h->type;
108 x86_init.hyper.init_platform();
109}
110

source code of linux/arch/x86/kernel/cpu/hypervisor.c