arch/x86/kernel/cpu/hypervisor.c

   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
  32         &x86_hyper_xen_pv,
  33         &x86_hyper_xen_hvm,
  34 #endif
  35         &x86_hyper_vmware,
  36         &x86_hyper_ms_hyperv,
  37 #ifdef CONFIG_KVM_GUEST
  38         &x86_hyper_kvm,
  39 #endif
  40 };
  41
  42 const struct hypervisor_x86 *x86_hyper;
  43 EXPORT_SYMBOL(x86_hyper);
  44
  45 static inline void __init
  46 detect_hypervisor_vendor(void)
  47 {
  48         const struct hypervisor_x86 *h, * const *p;
  49         uint32_t pri, max_pri = 0;
  50
  51         for (p = hypervisors; p < hypervisors + ARRAY_SIZE(hypervisors); p++) {
  52                 h = *p;
  53                 pri = h->detect();
  54                 if (pri != 0 && pri > max_pri) {
  55                         max_pri = pri;
  56                         x86_hyper = h;
  57                 }
  58         }
  59
  60         if (max_pri)
  61                 pr_info("Hypervisor detected: %s\n", x86_hyper->name);
  62 }
  63
  64 void init_hypervisor(struct cpuinfo_x86 *c)
  65 {
  66         if (x86_hyper && x86_hyper->set_cpu_features)
  67                 x86_hyper->set_cpu_features(c);
  68 }
  69
  70 void __init init_hypervisor_platform(void)
  71 {
  72
  73         detect_hypervisor_vendor();
  74
  75         if (!x86_hyper)
  76                 return;
  77
  78         init_hypervisor(&boot_cpu_data);
  79
  80         if (x86_hyper->init_platform)
  81                 x86_hyper->init_platform();
  82 }
  83
  84 bool __init hypervisor_x2apic_available(void)
  85 {
  86         return x86_hyper                   &&
  87                x86_hyper->x2apic_available &&
  88                x86_hyper->x2apic_available();
  89 }
  90
  91 void hypervisor_pin_vcpu(int cpu)
  92 {
  93         if (!x86_hyper)
  94                 return;
  95
  96         if (x86_hyper->pin_vcpu)
  97                 x86_hyper->pin_vcpu(cpu);
  98         else
  99                 WARN_ONCE(1, "vcpu pinning requested but not supported!\n");
 100 }