KVM: switch irq injection/acking data structures to irq_lock
[pandora-kernel.git] / virt / kvm / irq_comm.c
1 /*
2  * irq_comm.c: Common 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/kvm_host.h>
23
24 #include <asm/msidef.h>
25 #ifdef CONFIG_IA64
26 #include <asm/iosapic.h>
27 #endif
28
29 #include "irq.h"
30
31 #include "ioapic.h"
32
33 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
34                            struct kvm *kvm, int level)
35 {
36 #ifdef CONFIG_X86
37         return kvm_pic_set_irq(pic_irqchip(kvm), e->irqchip.pin, level);
38 #else
39         return -1;
40 #endif
41 }
42
43 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
44                               struct kvm *kvm, int level)
45 {
46         return kvm_ioapic_set_irq(kvm->arch.vioapic, e->irqchip.pin, level);
47 }
48
49 inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
50 {
51 #ifdef CONFIG_IA64
52         return irq->delivery_mode ==
53                 (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
54 #else
55         return irq->delivery_mode == APIC_DM_LOWEST;
56 #endif
57 }
58
59 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
60                 struct kvm_lapic_irq *irq)
61 {
62         int i, r = -1;
63         struct kvm_vcpu *vcpu, *lowest = NULL;
64
65         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
66
67         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
68                         kvm_is_dm_lowest_prio(irq))
69                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
70
71         for (i = 0; i < KVM_MAX_VCPUS; i++) {
72                 vcpu = kvm->vcpus[i];
73
74                 if (!vcpu || !kvm_apic_present(vcpu))
75                         continue;
76
77                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
78                                         irq->dest_id, irq->dest_mode))
79                         continue;
80
81                 if (!kvm_is_dm_lowest_prio(irq)) {
82                         if (r < 0)
83                                 r = 0;
84                         r += kvm_apic_set_irq(vcpu, irq);
85                 } else {
86                         if (!lowest)
87                                 lowest = vcpu;
88                         else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
89                                 lowest = vcpu;
90                 }
91         }
92
93         if (lowest)
94                 r = kvm_apic_set_irq(lowest, irq);
95
96         return r;
97 }
98
99 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
100                        struct kvm *kvm, int level)
101 {
102         struct kvm_lapic_irq irq;
103
104         irq.dest_id = (e->msi.address_lo &
105                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
106         irq.vector = (e->msi.data &
107                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
108         irq.dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
109         irq.trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
110         irq.delivery_mode = e->msi.data & 0x700;
111         irq.level = 1;
112         irq.shorthand = 0;
113
114         /* TODO Deal with RH bit of MSI message address */
115         return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
116 }
117
118 /* This should be called with the kvm->irq_lock mutex held
119  * Return value:
120  *  < 0   Interrupt was ignored (masked or not delivered for other reasons)
121  *  = 0   Interrupt was coalesced (previous irq is still pending)
122  *  > 0   Number of CPUs interrupt was delivered to
123  */
124 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
125 {
126         struct kvm_kernel_irq_routing_entry *e;
127         unsigned long *irq_state, sig_level;
128         int ret = -1;
129
130         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
131
132         if (irq < KVM_IOAPIC_NUM_PINS) {
133                 irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
134
135                 /* Logical OR for level trig interrupt */
136                 if (level)
137                         set_bit(irq_source_id, irq_state);
138                 else
139                         clear_bit(irq_source_id, irq_state);
140                 sig_level = !!(*irq_state);
141         } else /* Deal with MSI/MSI-X */
142                 sig_level = 1;
143
144         /* Not possible to detect if the guest uses the PIC or the
145          * IOAPIC.  So set the bit in both. The guest will ignore
146          * writes to the unused one.
147          */
148         list_for_each_entry(e, &kvm->irq_routing, link)
149                 if (e->gsi == irq) {
150                         int r = e->set(e, kvm, sig_level);
151                         if (r < 0)
152                                 continue;
153
154                         ret = r + ((ret < 0) ? 0 : ret);
155                 }
156         return ret;
157 }
158
159 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
160 {
161         struct kvm_kernel_irq_routing_entry *e;
162         struct kvm_irq_ack_notifier *kian;
163         struct hlist_node *n;
164         unsigned gsi = pin;
165
166         list_for_each_entry(e, &kvm->irq_routing, link)
167                 if (e->type == KVM_IRQ_ROUTING_IRQCHIP &&
168                     e->irqchip.irqchip == irqchip &&
169                     e->irqchip.pin == pin) {
170                         gsi = e->gsi;
171                         break;
172                 }
173
174         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
175                 if (kian->gsi == gsi)
176                         kian->irq_acked(kian);
177 }
178
179 void kvm_register_irq_ack_notifier(struct kvm *kvm,
180                                    struct kvm_irq_ack_notifier *kian)
181 {
182         mutex_lock(&kvm->irq_lock);
183         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
184         mutex_unlock(&kvm->irq_lock);
185 }
186
187 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
188                                     struct kvm_irq_ack_notifier *kian)
189 {
190         mutex_lock(&kvm->irq_lock);
191         hlist_del_init(&kian->link);
192         mutex_unlock(&kvm->irq_lock);
193 }
194
195 int kvm_request_irq_source_id(struct kvm *kvm)
196 {
197         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
198         int irq_source_id;
199
200         mutex_lock(&kvm->irq_lock);
201         irq_source_id = find_first_zero_bit(bitmap,
202                                 sizeof(kvm->arch.irq_sources_bitmap));
203
204         if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
205                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
206                 return -EFAULT;
207         }
208
209         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
210         set_bit(irq_source_id, bitmap);
211         mutex_unlock(&kvm->irq_lock);
212
213         return irq_source_id;
214 }
215
216 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
217 {
218         int i;
219
220         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
221
222         mutex_lock(&kvm->irq_lock);
223         if (irq_source_id < 0 ||
224             irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
225                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
226                 return;
227         }
228         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
229                 clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
230         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
231         mutex_unlock(&kvm->irq_lock);
232 }
233
234 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
235                                     struct kvm_irq_mask_notifier *kimn)
236 {
237         mutex_lock(&kvm->irq_lock);
238         kimn->irq = irq;
239         hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
240         mutex_unlock(&kvm->irq_lock);
241 }
242
243 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
244                                       struct kvm_irq_mask_notifier *kimn)
245 {
246         mutex_lock(&kvm->irq_lock);
247         hlist_del(&kimn->link);
248         mutex_unlock(&kvm->irq_lock);
249 }
250
251 void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
252 {
253         struct kvm_irq_mask_notifier *kimn;
254         struct hlist_node *n;
255
256         WARN_ON(!mutex_is_locked(&kvm->irq_lock));
257
258         hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
259                 if (kimn->irq == irq)
260                         kimn->func(kimn, mask);
261 }
262
263 static void __kvm_free_irq_routing(struct list_head *irq_routing)
264 {
265         struct kvm_kernel_irq_routing_entry *e, *n;
266
267         list_for_each_entry_safe(e, n, irq_routing, link)
268                 kfree(e);
269 }
270
271 void kvm_free_irq_routing(struct kvm *kvm)
272 {
273         mutex_lock(&kvm->irq_lock);
274         __kvm_free_irq_routing(&kvm->irq_routing);
275         mutex_unlock(&kvm->irq_lock);
276 }
277
278 static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
279                                const struct kvm_irq_routing_entry *ue)
280 {
281         int r = -EINVAL;
282         int delta;
283
284         e->gsi = ue->gsi;
285         e->type = ue->type;
286         switch (ue->type) {
287         case KVM_IRQ_ROUTING_IRQCHIP:
288                 delta = 0;
289                 switch (ue->u.irqchip.irqchip) {
290                 case KVM_IRQCHIP_PIC_MASTER:
291                         e->set = kvm_set_pic_irq;
292                         break;
293                 case KVM_IRQCHIP_PIC_SLAVE:
294                         e->set = kvm_set_pic_irq;
295                         delta = 8;
296                         break;
297                 case KVM_IRQCHIP_IOAPIC:
298                         e->set = kvm_set_ioapic_irq;
299                         break;
300                 default:
301                         goto out;
302                 }
303                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
304                 e->irqchip.pin = ue->u.irqchip.pin + delta;
305                 break;
306         case KVM_IRQ_ROUTING_MSI:
307                 e->set = kvm_set_msi;
308                 e->msi.address_lo = ue->u.msi.address_lo;
309                 e->msi.address_hi = ue->u.msi.address_hi;
310                 e->msi.data = ue->u.msi.data;
311                 break;
312         default:
313                 goto out;
314         }
315         r = 0;
316 out:
317         return r;
318 }
319
320
321 int kvm_set_irq_routing(struct kvm *kvm,
322                         const struct kvm_irq_routing_entry *ue,
323                         unsigned nr,
324                         unsigned flags)
325 {
326         struct list_head irq_list = LIST_HEAD_INIT(irq_list);
327         struct list_head tmp = LIST_HEAD_INIT(tmp);
328         struct kvm_kernel_irq_routing_entry *e = NULL;
329         unsigned i;
330         int r;
331
332         for (i = 0; i < nr; ++i) {
333                 r = -EINVAL;
334                 if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
335                         goto out;
336                 if (ue->flags)
337                         goto out;
338                 r = -ENOMEM;
339                 e = kzalloc(sizeof(*e), GFP_KERNEL);
340                 if (!e)
341                         goto out;
342                 r = setup_routing_entry(e, ue);
343                 if (r)
344                         goto out;
345                 ++ue;
346                 list_add(&e->link, &irq_list);
347                 e = NULL;
348         }
349
350         mutex_lock(&kvm->irq_lock);
351         list_splice(&kvm->irq_routing, &tmp);
352         INIT_LIST_HEAD(&kvm->irq_routing);
353         list_splice(&irq_list, &kvm->irq_routing);
354         INIT_LIST_HEAD(&irq_list);
355         list_splice(&tmp, &irq_list);
356         mutex_unlock(&kvm->irq_lock);
357
358         r = 0;
359
360 out:
361         kfree(e);
362         __kvm_free_irq_routing(&irq_list);
363         return r;
364 }
365
366 #define IOAPIC_ROUTING_ENTRY(irq) \
367         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
368           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
369 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
370
371 #ifdef CONFIG_X86
372 #  define PIC_ROUTING_ENTRY(irq) \
373         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
374           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
375 #  define ROUTING_ENTRY2(irq) \
376         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
377 #else
378 #  define ROUTING_ENTRY2(irq) \
379         IOAPIC_ROUTING_ENTRY(irq)
380 #endif
381
382 static const struct kvm_irq_routing_entry default_routing[] = {
383         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
384         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
385         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
386         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
387         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
388         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
389         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
390         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
391         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
392         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
393         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
394         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
395 #ifdef CONFIG_IA64
396         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
397         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
398         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
399         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
400         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
401         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
402         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
403         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
404         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
405         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
406         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
407         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
408 #endif
409 };
410
411 int kvm_setup_default_irq_routing(struct kvm *kvm)
412 {
413         return kvm_set_irq_routing(kvm, default_routing,
414                                    ARRAY_SIZE(default_routing), 0);
415 }