Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
[linux-2.6] / 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         if (irq->dest_mode == 0 && irq->dest_id == 0xff &&
66                         kvm_is_dm_lowest_prio(irq))
67                 printk(KERN_INFO "kvm: apic: phys broadcast and lowest prio\n");
68
69         for (i = 0; i < KVM_MAX_VCPUS; i++) {
70                 vcpu = kvm->vcpus[i];
71
72                 if (!vcpu || !kvm_apic_present(vcpu))
73                         continue;
74
75                 if (!kvm_apic_match_dest(vcpu, src, irq->shorthand,
76                                         irq->dest_id, irq->dest_mode))
77                         continue;
78
79                 if (!kvm_is_dm_lowest_prio(irq)) {
80                         if (r < 0)
81                                 r = 0;
82                         r += kvm_apic_set_irq(vcpu, irq);
83                 } else {
84                         if (!lowest)
85                                 lowest = vcpu;
86                         else if (kvm_apic_compare_prio(vcpu, lowest) < 0)
87                                 lowest = vcpu;
88                 }
89         }
90
91         if (lowest)
92                 r = kvm_apic_set_irq(lowest, irq);
93
94         return r;
95 }
96
97 static int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e,
98                        struct kvm *kvm, int level)
99 {
100         struct kvm_lapic_irq irq;
101
102         irq.dest_id = (e->msi.address_lo &
103                         MSI_ADDR_DEST_ID_MASK) >> MSI_ADDR_DEST_ID_SHIFT;
104         irq.vector = (e->msi.data &
105                         MSI_DATA_VECTOR_MASK) >> MSI_DATA_VECTOR_SHIFT;
106         irq.dest_mode = (1 << MSI_ADDR_DEST_MODE_SHIFT) & e->msi.address_lo;
107         irq.trig_mode = (1 << MSI_DATA_TRIGGER_SHIFT) & e->msi.data;
108         irq.delivery_mode = e->msi.data & 0x700;
109         irq.level = 1;
110         irq.shorthand = 0;
111
112         /* TODO Deal with RH bit of MSI message address */
113         return kvm_irq_delivery_to_apic(kvm, NULL, &irq);
114 }
115
116 /* This should be called with the kvm->lock mutex held
117  * Return value:
118  *  < 0   Interrupt was ignored (masked or not delivered for other reasons)
119  *  = 0   Interrupt was coalesced (previous irq is still pending)
120  *  > 0   Number of CPUs interrupt was delivered to
121  */
122 int kvm_set_irq(struct kvm *kvm, int irq_source_id, int irq, int level)
123 {
124         struct kvm_kernel_irq_routing_entry *e;
125         unsigned long *irq_state, sig_level;
126         int ret = -1;
127
128         if (irq < KVM_IOAPIC_NUM_PINS) {
129                 irq_state = (unsigned long *)&kvm->arch.irq_states[irq];
130
131                 /* Logical OR for level trig interrupt */
132                 if (level)
133                         set_bit(irq_source_id, irq_state);
134                 else
135                         clear_bit(irq_source_id, irq_state);
136                 sig_level = !!(*irq_state);
137         } else /* Deal with MSI/MSI-X */
138                 sig_level = 1;
139
140         /* Not possible to detect if the guest uses the PIC or the
141          * IOAPIC.  So set the bit in both. The guest will ignore
142          * writes to the unused one.
143          */
144         list_for_each_entry(e, &kvm->irq_routing, link)
145                 if (e->gsi == irq) {
146                         int r = e->set(e, kvm, sig_level);
147                         if (r < 0)
148                                 continue;
149
150                         ret = r + ((ret < 0) ? 0 : ret);
151                 }
152         return ret;
153 }
154
155 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
156 {
157         struct kvm_kernel_irq_routing_entry *e;
158         struct kvm_irq_ack_notifier *kian;
159         struct hlist_node *n;
160         unsigned gsi = pin;
161
162         list_for_each_entry(e, &kvm->irq_routing, link)
163                 if (e->irqchip.irqchip == irqchip &&
164                     e->irqchip.pin == pin) {
165                         gsi = e->gsi;
166                         break;
167                 }
168
169         hlist_for_each_entry(kian, n, &kvm->arch.irq_ack_notifier_list, link)
170                 if (kian->gsi == gsi)
171                         kian->irq_acked(kian);
172 }
173
174 void kvm_register_irq_ack_notifier(struct kvm *kvm,
175                                    struct kvm_irq_ack_notifier *kian)
176 {
177         hlist_add_head(&kian->link, &kvm->arch.irq_ack_notifier_list);
178 }
179
180 void kvm_unregister_irq_ack_notifier(struct kvm_irq_ack_notifier *kian)
181 {
182         hlist_del_init(&kian->link);
183 }
184
185 /* The caller must hold kvm->lock mutex */
186 int kvm_request_irq_source_id(struct kvm *kvm)
187 {
188         unsigned long *bitmap = &kvm->arch.irq_sources_bitmap;
189         int irq_source_id = find_first_zero_bit(bitmap,
190                                 sizeof(kvm->arch.irq_sources_bitmap));
191
192         if (irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
193                 printk(KERN_WARNING "kvm: exhaust allocatable IRQ sources!\n");
194                 return -EFAULT;
195         }
196
197         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
198         set_bit(irq_source_id, bitmap);
199
200         return irq_source_id;
201 }
202
203 void kvm_free_irq_source_id(struct kvm *kvm, int irq_source_id)
204 {
205         int i;
206
207         ASSERT(irq_source_id != KVM_USERSPACE_IRQ_SOURCE_ID);
208
209         if (irq_source_id < 0 ||
210             irq_source_id >= sizeof(kvm->arch.irq_sources_bitmap)) {
211                 printk(KERN_ERR "kvm: IRQ source ID out of range!\n");
212                 return;
213         }
214         for (i = 0; i < KVM_IOAPIC_NUM_PINS; i++)
215                 clear_bit(irq_source_id, &kvm->arch.irq_states[i]);
216         clear_bit(irq_source_id, &kvm->arch.irq_sources_bitmap);
217 }
218
219 void kvm_register_irq_mask_notifier(struct kvm *kvm, int irq,
220                                     struct kvm_irq_mask_notifier *kimn)
221 {
222         kimn->irq = irq;
223         hlist_add_head(&kimn->link, &kvm->mask_notifier_list);
224 }
225
226 void kvm_unregister_irq_mask_notifier(struct kvm *kvm, int irq,
227                                       struct kvm_irq_mask_notifier *kimn)
228 {
229         hlist_del(&kimn->link);
230 }
231
232 void kvm_fire_mask_notifiers(struct kvm *kvm, int irq, bool mask)
233 {
234         struct kvm_irq_mask_notifier *kimn;
235         struct hlist_node *n;
236
237         hlist_for_each_entry(kimn, n, &kvm->mask_notifier_list, link)
238                 if (kimn->irq == irq)
239                         kimn->func(kimn, mask);
240 }
241
242 static void __kvm_free_irq_routing(struct list_head *irq_routing)
243 {
244         struct kvm_kernel_irq_routing_entry *e, *n;
245
246         list_for_each_entry_safe(e, n, irq_routing, link)
247                 kfree(e);
248 }
249
250 void kvm_free_irq_routing(struct kvm *kvm)
251 {
252         __kvm_free_irq_routing(&kvm->irq_routing);
253 }
254
255 static int setup_routing_entry(struct kvm_kernel_irq_routing_entry *e,
256                                const struct kvm_irq_routing_entry *ue)
257 {
258         int r = -EINVAL;
259         int delta;
260
261         e->gsi = ue->gsi;
262         switch (ue->type) {
263         case KVM_IRQ_ROUTING_IRQCHIP:
264                 delta = 0;
265                 switch (ue->u.irqchip.irqchip) {
266                 case KVM_IRQCHIP_PIC_MASTER:
267                         e->set = kvm_set_pic_irq;
268                         break;
269                 case KVM_IRQCHIP_PIC_SLAVE:
270                         e->set = kvm_set_pic_irq;
271                         delta = 8;
272                         break;
273                 case KVM_IRQCHIP_IOAPIC:
274                         e->set = kvm_set_ioapic_irq;
275                         break;
276                 default:
277                         goto out;
278                 }
279                 e->irqchip.irqchip = ue->u.irqchip.irqchip;
280                 e->irqchip.pin = ue->u.irqchip.pin + delta;
281                 break;
282         case KVM_IRQ_ROUTING_MSI:
283                 e->set = kvm_set_msi;
284                 e->msi.address_lo = ue->u.msi.address_lo;
285                 e->msi.address_hi = ue->u.msi.address_hi;
286                 e->msi.data = ue->u.msi.data;
287                 break;
288         default:
289                 goto out;
290         }
291         r = 0;
292 out:
293         return r;
294 }
295
296
297 int kvm_set_irq_routing(struct kvm *kvm,
298                         const struct kvm_irq_routing_entry *ue,
299                         unsigned nr,
300                         unsigned flags)
301 {
302         struct list_head irq_list = LIST_HEAD_INIT(irq_list);
303         struct list_head tmp = LIST_HEAD_INIT(tmp);
304         struct kvm_kernel_irq_routing_entry *e = NULL;
305         unsigned i;
306         int r;
307
308         for (i = 0; i < nr; ++i) {
309                 r = -EINVAL;
310                 if (ue->gsi >= KVM_MAX_IRQ_ROUTES)
311                         goto out;
312                 if (ue->flags)
313                         goto out;
314                 r = -ENOMEM;
315                 e = kzalloc(sizeof(*e), GFP_KERNEL);
316                 if (!e)
317                         goto out;
318                 r = setup_routing_entry(e, ue);
319                 if (r)
320                         goto out;
321                 ++ue;
322                 list_add(&e->link, &irq_list);
323                 e = NULL;
324         }
325
326         mutex_lock(&kvm->lock);
327         list_splice(&kvm->irq_routing, &tmp);
328         INIT_LIST_HEAD(&kvm->irq_routing);
329         list_splice(&irq_list, &kvm->irq_routing);
330         INIT_LIST_HEAD(&irq_list);
331         list_splice(&tmp, &irq_list);
332         mutex_unlock(&kvm->lock);
333
334         r = 0;
335
336 out:
337         kfree(e);
338         __kvm_free_irq_routing(&irq_list);
339         return r;
340 }
341
342 #define IOAPIC_ROUTING_ENTRY(irq) \
343         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
344           .u.irqchip.irqchip = KVM_IRQCHIP_IOAPIC, .u.irqchip.pin = (irq) }
345 #define ROUTING_ENTRY1(irq) IOAPIC_ROUTING_ENTRY(irq)
346
347 #ifdef CONFIG_X86
348 #  define PIC_ROUTING_ENTRY(irq) \
349         { .gsi = irq, .type = KVM_IRQ_ROUTING_IRQCHIP,  \
350           .u.irqchip.irqchip = SELECT_PIC(irq), .u.irqchip.pin = (irq) % 8 }
351 #  define ROUTING_ENTRY2(irq) \
352         IOAPIC_ROUTING_ENTRY(irq), PIC_ROUTING_ENTRY(irq)
353 #else
354 #  define ROUTING_ENTRY2(irq) \
355         IOAPIC_ROUTING_ENTRY(irq)
356 #endif
357
358 static const struct kvm_irq_routing_entry default_routing[] = {
359         ROUTING_ENTRY2(0), ROUTING_ENTRY2(1),
360         ROUTING_ENTRY2(2), ROUTING_ENTRY2(3),
361         ROUTING_ENTRY2(4), ROUTING_ENTRY2(5),
362         ROUTING_ENTRY2(6), ROUTING_ENTRY2(7),
363         ROUTING_ENTRY2(8), ROUTING_ENTRY2(9),
364         ROUTING_ENTRY2(10), ROUTING_ENTRY2(11),
365         ROUTING_ENTRY2(12), ROUTING_ENTRY2(13),
366         ROUTING_ENTRY2(14), ROUTING_ENTRY2(15),
367         ROUTING_ENTRY1(16), ROUTING_ENTRY1(17),
368         ROUTING_ENTRY1(18), ROUTING_ENTRY1(19),
369         ROUTING_ENTRY1(20), ROUTING_ENTRY1(21),
370         ROUTING_ENTRY1(22), ROUTING_ENTRY1(23),
371 #ifdef CONFIG_IA64
372         ROUTING_ENTRY1(24), ROUTING_ENTRY1(25),
373         ROUTING_ENTRY1(26), ROUTING_ENTRY1(27),
374         ROUTING_ENTRY1(28), ROUTING_ENTRY1(29),
375         ROUTING_ENTRY1(30), ROUTING_ENTRY1(31),
376         ROUTING_ENTRY1(32), ROUTING_ENTRY1(33),
377         ROUTING_ENTRY1(34), ROUTING_ENTRY1(35),
378         ROUTING_ENTRY1(36), ROUTING_ENTRY1(37),
379         ROUTING_ENTRY1(38), ROUTING_ENTRY1(39),
380         ROUTING_ENTRY1(40), ROUTING_ENTRY1(41),
381         ROUTING_ENTRY1(42), ROUTING_ENTRY1(43),
382         ROUTING_ENTRY1(44), ROUTING_ENTRY1(45),
383         ROUTING_ENTRY1(46), ROUTING_ENTRY1(47),
384 #endif
385 };
386
387 int kvm_setup_default_irq_routing(struct kvm *kvm)
388 {
389         return kvm_set_irq_routing(kvm, default_routing,
390                                    ARRAY_SIZE(default_routing), 0);
391 }