kernel/arch/x86/kvm/irq.c

   1 /*
   2  * irq.c: API for in kernel interrupt controller
   3  * Copyright (c) 2007, Intel Corporation.
   4  * Copyright 2009 Red Hat, Inc. and/or its affiliates.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along with
  16  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  17  * Place - Suite 330, Boston, MA 02111-1307 USA.
  18  * Authors:
  19  *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
  20  *
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/kvm_host.h>
  25
  26 #include "irq.h"
  27 #include "i8254.h"
  28 #include "x86.h"
  29
  30 /*
  31  * check if there are pending timer events
  32  * to be processed.
  33  */
  34 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
  35 {
  36         return apic_has_pending_timer(vcpu);
  37 }
  38 EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
  39
  40 /*
  41  * check if there is pending interrupt from
  42  * non-APIC source without intack.
  43  */
  44 static int kvm_cpu_has_extint(struct kvm_vcpu *v)
  45 {
  46         if (kvm_apic_accept_pic_intr(v))
  47                 return pic_irqchip(v->kvm)->output;     /* PIC */
  48         else
  49                 return 0;
  50 }
  51
  52 /*
  53  * check if there is injectable interrupt:
  54  * when virtual interrupt delivery enabled,
  55  * interrupt from apic will handled by hardware,
  56  * we don't need to check it here.
  57  */
  58 int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
  59 {
  60         if (!irqchip_in_kernel(v->kvm))
  61                 return v->arch.interrupt.pending;
  62
  63         if (kvm_cpu_has_extint(v))
  64                 return 1;
  65
  66         if (kvm_apic_vid_enabled(v->kvm))
  67                 return 0;
  68
  69         return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
  70 }
  71
  72 /*
  73  * check if there is pending interrupt without
  74  * intack.
  75  */
  76 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
  77 {
  78         if (!irqchip_in_kernel(v->kvm))
  79                 return v->arch.interrupt.pending;
  80
  81         if (kvm_cpu_has_extint(v))
  82                 return 1;
  83
  84         return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
  85 }
  86 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
  87
  88 /*
  89  * Read pending interrupt(from non-APIC source)
  90  * vector and intack.
  91  */
  92 static int kvm_cpu_get_extint(struct kvm_vcpu *v)
  93 {
  94         if (kvm_cpu_has_extint(v))
  95                 return kvm_pic_read_irq(v->kvm); /* PIC */
  96         return -1;
  97 }
  98
  99 /*
 100  * Read pending interrupt vector and intack.
 101  */
 102 int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
 103 {
 104         int vector;
 105
 106         if (!irqchip_in_kernel(v->kvm))
 107                 return v->arch.interrupt.nr;
 108
 109         vector = kvm_cpu_get_extint(v);
 110
 111         if (vector != -1)
 112                 return vector;                  /* PIC */
 113
 114         return kvm_get_apic_interrupt(v);       /* APIC */
 115 }
 116 EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
 117
 118 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
 119 {
 120         kvm_inject_apic_timer_irqs(vcpu);
 121         /* TODO: PIT, RTC etc. */
 122 }
 123 EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
 124
 125 void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
 126 {
 127         __kvm_migrate_apic_timer(vcpu);
 128         __kvm_migrate_pit_timer(vcpu);
 129 }