KVM: Add irq ack notifier list
[linux-2.6.git] / arch / x86 / kvm / irq.c
1 /*
2  * irq.c: API for in kernel interrupt controller
3  * Copyright (c) 2007, Intel Corporation.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms and conditions of the GNU General Public License,
7  * version 2, as published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
16  * Place - Suite 330, Boston, MA 02111-1307 USA.
17  * Authors:
18  *   Yaozu (Eddie) Dong <Eddie.dong@intel.com>
19  *
20  */
21
22 #include <linux/module.h>
23 #include <linux/kvm_host.h>
24
25 #include "irq.h"
26 #include "i8254.h"
27
28 /*
29  * check if there are pending timer events
30  * to be processed.
31  */
32 int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
33 {
34         int ret;
35
36         ret = pit_has_pending_timer(vcpu);
37         ret |= apic_has_pending_timer(vcpu);
38
39         return ret;
40 }
41 EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
42
43 /*
44  * check if there is pending interrupt without
45  * intack.
46  */
47 int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
48 {
49         struct kvm_pic *s;
50
51         if (kvm_apic_has_interrupt(v) == -1) {  /* LAPIC */
52                 if (kvm_apic_accept_pic_intr(v)) {
53                         s = pic_irqchip(v->kvm);        /* PIC */
54                         return s->output;
55                 } else
56                         return 0;
57         }
58         return 1;
59 }
60 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
61
62 /*
63  * Read pending interrupt vector and intack.
64  */
65 int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
66 {
67         struct kvm_pic *s;
68         int vector;
69
70         vector = kvm_get_apic_interrupt(v);     /* APIC */
71         if (vector == -1) {
72                 if (kvm_apic_accept_pic_intr(v)) {
73                         s = pic_irqchip(v->kvm);
74                         s->output = 0;          /* PIC */
75                         vector = kvm_pic_read_irq(s);
76                 }
77         }
78         return vector;
79 }
80 EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
81
82 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
83 {
84         kvm_inject_apic_timer_irqs(vcpu);
85         kvm_inject_pit_timer_irqs(vcpu);
86         /* TODO: PIT, RTC etc. */
87 }
88 EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
89
90 void kvm_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
91 {
92         kvm_apic_timer_intr_post(vcpu, vec);
93         kvm_pit_timer_intr_post(vcpu, vec);
94         /* TODO: PIT, RTC etc. */
95 }
96 EXPORT_SYMBOL_GPL(kvm_timer_intr_post);
97
98 void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
99 {
100         __kvm_migrate_apic_timer(vcpu);
101         __kvm_migrate_pit_timer(vcpu);
102 }
103
104 /* This should be called with the kvm->lock mutex held */
105 void kvm_set_irq(struct kvm *kvm, int irq, int level)
106 {
107         /* Not possible to detect if the guest uses the PIC or the
108          * IOAPIC.  So set the bit in both. The guest will ignore
109          * writes to the unused one.
110          */
111         kvm_ioapic_set_irq(kvm->arch.vioapic, irq, level);
112         kvm_pic_set_irq(pic_irqchip(kvm), irq, level);
113 }
114
115 void kvm_notify_acked_irq(struct kvm *kvm, unsigned gsi)
116 {
117         struct kvm_irq_ack_notifier *kian;
118         struct hlist_node *n;
119
120         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
121                 if (kian->gsi == gsi)
122                         kian->irq_acked(kian);
123 }
124
125 void kvm_register_irq_ack_notifier(struct kvm *kvm,
126                                    struct kvm_irq_ack_notifier *kian)
127 {
128         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
129 }
130
131 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
132                                      struct kvm_irq_ack_notifier *kian)
133 {
134         hlist_del(&kian->link);
135 }