KVM: use 'writable' as a hint to map writable pfn
[linux-3.10.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  * Copyright 2010 Red Hat, Inc. and/or its affiliates.
21  */
22
23 #include <linux/kvm_host.h>
24 #include <linux/slab.h>
25 #include <trace/events/kvm.h>
26
27 #include <asm/msidef.h>
28 #ifdef CONFIG_IA64
29 #include <asm/iosapic.h>
30 #endif
31
32 #include "irq.h"
33
34 #include "ioapic.h"
35
36 static int kvm_set_pic_irq(struct kvm_kernel_irq_routing_entry *e,
37                            struct kvm *kvm, int irq_source_id, int level)
38 {
39 #ifdef CONFIG_X86
40         struct kvm_pic *pic = pic_irqchip(kvm);
41         return kvm_pic_set_irq(pic, e->irqchip.pin, irq_source_id, level);
42 #else
43         return -1;
44 #endif
45 }
46
47 static int kvm_set_ioapic_irq(struct kvm_kernel_irq_routing_entry *e,
48                               struct kvm *kvm, int irq_source_id, int level)
49 {
50         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
51         return kvm_ioapic_set_irq(ioapic, e->irqchip.pin, irq_source_id, level);
52 }
53
54 inline static bool kvm_is_dm_lowest_prio(struct kvm_lapic_irq *irq)
55 {
56 #ifdef CONFIG_IA64
57         return irq->delivery_mode ==
58                 (IOSAPIC_LOWEST_PRIORITY << IOSAPIC_DELIVERY_SHIFT);
59 #else
60         return irq->delivery_mode == APIC_DM_LOWEST;
61 #endif
62 }
63
64 int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
65                 struct kvm_lapic_irq *irq)
66 {
67         int i, r = -1;
68         struct kvm_vcpu *vcpu, *lowest = NULL;
69
70         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
71                         kvm_is_dm_lowest_prio(irq))
72                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
73
74         kvm_for_each_vcpu(i, vcpu, kvm) {
75                 if (!kvm_apic_present(vcpu))
76                         continue;
77
78                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
79                                         irq->dest_id, irq->dest_mode))
80                         continue;
81
82                 if (!kvm_is_dm_lowest_prio(irq)) {
83                         if (r < 0)
84                                 r = 0;
85                         r += kvm_apic_set_irq(vcpu, irq);
86                 } else if (kvm_lapic_enabled(vcpu)) {
87                         if (!lowest)
88                                 lowest = vcpu;
89                         else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
90                                 lowest = vcpu;
91                 }
92         }
93
94         if (lowest)
95                 r = kvm_apic_set_irq(lowest, irq);
96
97         return r;
98 }
99
100 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
101                 struct kvm *kvm, int irq_source_id, int level)
102 {
103         struct kvm_lapic_irq irq;
104
105         if (!level)
106                 return -1;
107
108         trace_kvm_msi_set_irq(e->msi.address_lo, e->msi.data);
109
110         irq.dest_id = (e->msi.address_lo &
111                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
112         irq.vector = (e->msi.data &
113                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
114         irq.dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
115         irq.trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
116         irq.delivery_mode = e->msi.data & 0x700;
117         irq.level = 1;
118         irq.shorthand = 0;
119
120         /* TODO Deal with RH bit of MSI message address */
121         return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
122 }
123
124 int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi)
125 {
126         struct kvm_kernel_irq_routing_entry route;
127
128         if (!irqchip_in_kernel(kvm) || msi->flags != 0)
129                 return -EINVAL;
130
131         route.msi.address_lo = msi->address_lo;
132         route.msi.address_hi = msi->address_hi;
133         route.msi.data = msi->data;
134
135         return kvm_set_msi(&route, kvm, KVM_USERSPACE_IRQ_SOURCE_ID, 1);
136 }
137
138 /*
139  * Return value:
140  *  < 0   Interrupt was ignored (masked or not delivered for other reasons)
141  *  = 0   Interrupt was coalesced (previous irq is still pending)
142  *  > 0   Number of CPUs interrupt was delivered to
143  */
144 int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level)
145 {
146         struct kvm_kernel_irq_routing_entry *e, irq_set[KVM_NR_IRQCHIPS];
147         int ret = -1, i = 0;
148         struct kvm_irq_routing_table *irq_rt;
149         struct hlist_node *n;
150
151         trace_kvm_set_irq(irq, level, irq_source_id);
152
153         /* Not possible to detect if the guest uses the PIC or the
154          * IOAPIC.  So set the bit in both. The guest will ignore
155          * writes to the unused one.
156          */
157         rcu_read_lock();
158         irq_rt = rcu_dereference(kvm->irq_routing);
159         if (irq < irq_rt->nr_rt_entries)
160                 hlist_for_each_entry(e, n, &irq_rt->map[irq], link)
161                         irq_set[i++] = *e;
162         rcu_read_unlock();
163
164         while(i--) {
165                 int r;
166                 r = irq_set[i].set(&irq_set[i], kvm, irq_source_id, level);
167                 if (r < 0)
168                         continue;
169
170                 ret = r + ((ret < 0) ? 0 : ret);
171         }
172
173         return ret;
174 }
175
176 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
177 {
178         struct kvm_irq_ack_notifier *kian;
179         struct hlist_node *n;
180         int gsi;
181
182         trace_kvm_ack_irq(irqchip, pin);
183
184         rcu_read_lock();
185         gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
186         if (gsi != -1)
187                 hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
188                                          link)
189                         if (kian->gsi == gsi)
190                                 kian->irq_acked(kian);
191         rcu_read_unlock();
192 }
193
194 void kvm_register_irq_ack_notifier(struct kvm *kvm,
195                                    struct kvm_irq_ack_notifier *kian)
196 {
197         mutex_lock(&kvm->irq_lock);
198         hlist_add_head_rcu(&kian->link, &kvm->irq_ack_notifier_list);
199         mutex_unlock(&kvm->irq_lock);
200 }
201
202 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
203                                     struct kvm_irq_ack_notifier *kian)
204 {
205         mutex_lock(&kvm->irq_lock);
206         hlist_del_init_rcu(&kian->link);
207         mutex_unlock(&kvm->irq_lock);
208         synchronize_rcu();
209 }
210
211 int kvm_request_irq_source_id(struct kvm *kvm)
212 {
213         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
214         int irq_source_id;
215
216         mutex_lock(&kvm->irq_lock);
217         irq_source_id = find_first_zero_bit(bitmap, BITS_PER_LONG);
218
219         if (irq_source_id >= BITS_PER_LONG) {
220                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
221                 irq_source_id = -EFAULT;
222                 goto unlock;
223         }
224
225         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
226         set_bit(irq_source_id, bitmap);
227 unlock:
228         mutex_unlock(&kvm->irq_lock);
229
230         return irq_source_id;
231 }
232
233 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
234 {
235         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
236
237         mutex_lock(&kvm->irq_lock);
238         if (irq_source_id < 0 ||
239             irq_source_id >= BITS_PER_LONG) {
240                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
241                 goto unlock;
242         }
243         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
244         if (!irqchip_in_kernel(kvm))
245                 goto unlock;
246
247         kvm_ioapic_clear_all(kvm->arch.vioapic, irq_source_id);
248 #ifdef CONFIG_X86
249         kvm_pic_clear_all(pic_irqchip(kvm), irq_source_id);
250 #endif
251 unlock:
252         mutex_unlock(&kvm->irq_lock);
253 }
254
255 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
256                                     struct kvm_irq_mask_notifier *kimn)
257 {
258         mutex_lock(&kvm->irq_lock);
259         kimn->irq = irq;
260         hlist_add_head_rcu(&kimn->link, &kvm->mask_notifier_list);
261         mutex_unlock(&kvm->irq_lock);
262 }
263
264 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
265                                       struct kvm_irq_mask_notifier *kimn)
266 {
267         mutex_lock(&kvm->irq_lock);
268         hlist_del_rcu(&kimn->link);
269         mutex_unlock(&kvm->irq_lock);
270         synchronize_rcu();
271 }
272
273 void kvm_fire_mask_notifiers(struct kvm *kvm, unsigned irqchip, unsigned pin,
274                              bool mask)
275 {
276         struct kvm_irq_mask_notifier *kimn;
277         struct hlist_node *n;
278         int gsi;
279
280         rcu_read_lock();
281         gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
282         if (gsi != -1)
283                 hlist_for_each_entry_rcu(kimn, n, &kvm->mask_notifier_list, link)
284                         if (kimn->irq == gsi)
285                                 kimn->func(kimn, mask);
286         rcu_read_unlock();
287 }
288
289 void kvm_free_irq_routing(struct kvm *kvm)
290 {
291         /* Called only during vm destruction. Nobody can use the pointer
292            at this stage */
293         kfree(kvm->irq_routing);
294 }
295
296 static int setup_routing_entry(struct kvm_irq_routing_table *rt,
297                                struct kvm_kernel_irq_routing_entry *e,
298                                const struct kvm_irq_routing_entry *ue)
299 {
300         int r = -EINVAL;
301         int delta;
302         unsigned max_pin;
303         struct kvm_kernel_irq_routing_entry *ei;
304         struct hlist_node *n;
305
306         /*
307          * Do not allow GSI to be mapped to the same irqchip more than once.
308          * Allow only one to one mapping between GSI and MSI.
309          */
310         hlist_for_each_entry(ei, n, &rt->map[ue->gsi], link)
311                 if (ei->type == KVM_IRQ_ROUTING_MSI ||
312                     ue->type == KVM_IRQ_ROUTING_MSI ||
313                     ue->u.irqchip.irqchip == ei->irqchip.irqchip)
314                         return r;
315
316         e->gsi = ue->gsi;
317         e->type = ue->type;
318         switch (ue->type) {
319         case KVM_IRQ_ROUTING_IRQCHIP:
320                 delta = 0;
321                 switch (ue->u.irqchip.irqchip) {
322                 case KVM_IRQCHIP_PIC_MASTER:
323                         e->set = kvm_set_pic_irq;
324                         max_pin = PIC_NUM_PINS;
325                         break;
326                 case KVM_IRQCHIP_PIC_SLAVE:
327                         e->set = kvm_set_pic_irq;
328                         max_pin = PIC_NUM_PINS;
329                         delta = 8;
330                         break;
331                 case KVM_IRQCHIP_IOAPIC:
332                         max_pin = KVM_IOAPIC_NUM_PINS;
333                         e->set = kvm_set_ioapic_irq;
334                         break;
335                 default:
336                         goto out;
337                 }
338                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
339                 e->irqchip.pin = ue->u.irqchip.pin + delta;
340                 if (e->irqchip.pin >= max_pin)
341                         goto out;
342                 rt->chip[ue->u.irqchip.irqchip][e->irqchip.pin] = ue->gsi;
343                 break;
344         case KVM_IRQ_ROUTING_MSI:
345                 e->set = kvm_set_msi;
346                 e->msi.address_lo = ue->u.msi.address_lo;
347                 e->msi.address_hi = ue->u.msi.address_hi;
348                 e->msi.data = ue->u.msi.data;
349                 break;
350         default:
351                 goto out;
352         }
353
354         hlist_add_head(&e->link, &rt->map[e->gsi]);
355         r = 0;
356 out:
357         return r;
358 }
359
360
361 int kvm_set_irq_routing(struct kvm *kvm,
362                         const struct kvm_irq_routing_entry *ue,
363                         unsigned nr,
364                         unsigned flags)
365 {
366         struct kvm_irq_routing_table *new, *old;
367         u32 i, j, nr_rt_entries = 0;
368         int r;
369
370         for (i = 0; i < nr; ++i) {
371                 if (ue[i].gsi >= KVM_MAX_IRQ_ROUTES)
372                         return -EINVAL;
373                 nr_rt_entries = max(nr_rt_entries, ue[i].gsi);
374         }
375
376         nr_rt_entries += 1;
377
378         new = kzalloc(sizeof(*new) + (nr_rt_entries * sizeof(struct hlist_head))
379                       + (nr * sizeof(struct kvm_kernel_irq_routing_entry)),
380                       GFP_KERNEL);
381
382         if (!new)
383                 return -ENOMEM;
384
385         new->rt_entries = (void *)&new->map[nr_rt_entries];
386
387         new->nr_rt_entries = nr_rt_entries;
388         for (i = 0; i < 3; i++)
389                 for (j = 0; j < KVM_IOAPIC_NUM_PINS; j++)
390                         new->chip[i][j] = -1;
391
392         for (i = 0; i < nr; ++i) {
393                 r = -EINVAL;
394                 if (ue->flags)
395                         goto out;
396                 r = setup_routing_entry(new, &new->rt_entries[i], ue);
397                 if (r)
398                         goto out;
399                 ++ue;
400         }
401
402         mutex_lock(&kvm->irq_lock);
403         old = kvm->irq_routing;
404         kvm_irq_routing_update(kvm, new);
405         mutex_unlock(&kvm->irq_lock);
406
407         synchronize_rcu();
408
409         new = old;
410         r = 0;
411
412 out:
413         kfree(new);
414         return r;
415 }
416
417 #define IOAPIC_ROUTING_ENTRY(irq) \
418         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
419           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
420 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
421
422 #ifdef CONFIG_X86
423 #  define PIC_ROUTING_ENTRY(irq) \
424         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
425           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
426 #  define ROUTING_ENTRY2(irq) \
427         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
428 #else
429 #  define ROUTING_ENTRY2(irq) \
430         IOAPIC_ROUTING_ENTRY(irq)
431 #endif
432
433 static const struct kvm_irq_routing_entry default_routing[] = {
434         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
435         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
436         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
437         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
438         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
439         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
440         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
441         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
442         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
443         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
444         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
445         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
446 #ifdef CONFIG_IA64
447         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
448         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
449         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
450         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
451         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
452         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
453         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
454         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
455         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
456         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
457         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
458         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
459 #endif
460 };
461
462 int kvm_setup_default_irq_routing(struct kvm *kvm)
463 {
464         return kvm_set_irq_routing(kvm, default_routing,
465                                    ARRAY_SIZE(default_routing), 0);
466 }