Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / virt / kvm / ioapic.c
1 /*
2  *  Copyright (C) 2001  MandrakeSoft S.A.
3  *
4  *    MandrakeSoft S.A.
5  *    43, rue d'Aboukir
6  *    75002 Paris - France
7  *    http://www.linux-mandrake.com/
8  *    http://www.mandrakesoft.com/
9  *
10  *  This library is free software; you can redistribute it and/or
11  *  modify it under the terms of the GNU Lesser General Public
12  *  License as published by the Free Software Foundation; either
13  *  version 2 of the License, or (at your option) any later version.
14  *
15  *  This library is distributed in the hope that it will be useful,
16  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  Lesser General Public License for more details.
19  *
20  *  You should have received a copy of the GNU Lesser General Public
21  *  License along with this library; if not, write to the Free Software
22  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
23  *
24  *  Yunhong Jiang <yunhong.jiang@intel.com>
25  *  Yaozu (Eddie) Dong <eddie.dong@intel.com>
26  *  Based on Xen 3.1 code.
27  */
28
29 #include <linux/kvm_host.h>
30 #include <linux/kvm.h>
31 #include <linux/mm.h>
32 #include <linux/highmem.h>
33 #include <linux/smp.h>
34 #include <linux/hrtimer.h>
35 #include <linux/io.h>
36 #include <asm/processor.h>
37 #include <asm/page.h>
38 #include <asm/current.h>
39 #include <trace/events/kvm.h>
40
41 #include "ioapic.h"
42 #include "lapic.h"
43 #include "irq.h"
44
45 #if 0
46 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
47 #else
48 #define ioapic_debug(fmt, arg...)
49 #endif
50 static int ioapic_deliver(struct kvm_ioapic *vioapic, int irq);
51
52 static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
53                                           unsigned long addr,
54                                           unsigned long length)
55 {
56         unsigned long result = 0;
57
58         switch (ioapic->ioregsel) {
59         case IOAPIC_REG_VERSION:
60                 result = ((((IOAPIC_NUM_PINS - 1) & 0xff) << 16)
61                           | (IOAPIC_VERSION_ID & 0xff));
62                 break;
63
64         case IOAPIC_REG_APIC_ID:
65         case IOAPIC_REG_ARB_ID:
66                 result = ((ioapic->id & 0xf) << 24);
67                 break;
68
69         default:
70                 {
71                         u32 redir_index = (ioapic->ioregsel - 0x10) >> 1;
72                         u64 redir_content;
73
74                         ASSERT(redir_index < IOAPIC_NUM_PINS);
75
76                         redir_content = ioapic->redirtbl[redir_index].bits;
77                         result = (ioapic->ioregsel & 0x1) ?
78                             (redir_content >> 32) & 0xffffffff :
79                             redir_content & 0xffffffff;
80                         break;
81                 }
82         }
83
84         return result;
85 }
86
87 static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
88 {
89         union kvm_ioapic_redirect_entry *pent;
90         int injected = -1;
91
92         pent = &ioapic->redirtbl[idx];
93
94         if (!pent->fields.mask) {
95                 injected = ioapic_deliver(ioapic, idx);
96                 if (injected && pent->fields.trig_mode == IOAPIC_LEVEL_TRIG)
97                         pent->fields.remote_irr = 1;
98         }
99
100         return injected;
101 }
102
103 static void update_handled_vectors(struct kvm_ioapic *ioapic)
104 {
105         DECLARE_BITMAP(handled_vectors, 256);
106         int i;
107
108         memset(handled_vectors, 0, sizeof(handled_vectors));
109         for (i = 0; i < IOAPIC_NUM_PINS; ++i)
110                 __set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
111         memcpy(ioapic->handled_vectors, handled_vectors,
112                sizeof(handled_vectors));
113         smp_wmb();
114 }
115
116 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
117 {
118         unsigned index;
119         bool mask_before, mask_after;
120         union kvm_ioapic_redirect_entry *e;
121
122         switch (ioapic->ioregsel) {
123         case IOAPIC_REG_VERSION:
124                 /* Writes are ignored. */
125                 break;
126
127         case IOAPIC_REG_APIC_ID:
128                 ioapic->id = (val >> 24) & 0xf;
129                 break;
130
131         case IOAPIC_REG_ARB_ID:
132                 break;
133
134         default:
135                 index = (ioapic->ioregsel - 0x10) >> 1;
136
137                 ioapic_debug("change redir index %x val %x\n", index, val);
138                 if (index >= IOAPIC_NUM_PINS)
139                         return;
140                 e = &ioapic->redirtbl[index];
141                 mask_before = e->fields.mask;
142                 if (ioapic->ioregsel & 1) {
143                         e->bits &= 0xffffffff;
144                         e->bits |= (u64) val << 32;
145                 } else {
146                         e->bits &= ~0xffffffffULL;
147                         e->bits |= (u32) val;
148                         e->fields.remote_irr = 0;
149                 }
150                 update_handled_vectors(ioapic);
151                 mask_after = e->fields.mask;
152                 if (mask_before != mask_after)
153                         kvm_fire_mask_notifiers(ioapic->kvm, index, mask_after);
154                 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
155                     && ioapic->irr & (1 << index))
156                         ioapic_service(ioapic, index);
157                 break;
158         }
159 }
160
161 static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
162 {
163         union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
164         struct kvm_lapic_irq irqe;
165
166         ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
167                      "vector=%x trig_mode=%x\n",
168                      entry->fields.dest, entry->fields.dest_mode,
169                      entry->fields.delivery_mode, entry->fields.vector,
170                      entry->fields.trig_mode);
171
172         irqe.dest_id = entry->fields.dest_id;
173         irqe.vector = entry->fields.vector;
174         irqe.dest_mode = entry->fields.dest_mode;
175         irqe.trig_mode = entry->fields.trig_mode;
176         irqe.delivery_mode = entry->fields.delivery_mode << 8;
177         irqe.level = 1;
178         irqe.shorthand = 0;
179
180 #ifdef CONFIG_X86
181         /* Always delivery PIT interrupt to vcpu 0 */
182         if (irq == 0) {
183                 irqe.dest_mode = 0; /* Physical mode. */
184                 /* need to read apic_id from apic regiest since
185                  * it can be rewritten */
186                 irqe.dest_id = ioapic->kvm->bsp_vcpu->vcpu_id;
187         }
188 #endif
189         return kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe);
190 }
191
192 int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
193 {
194         u32 old_irr = ioapic->irr;
195         u32 mask = 1 << irq;
196         union kvm_ioapic_redirect_entry entry;
197         int ret = 1;
198
199         mutex_lock(&ioapic->lock);
200         if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
201                 entry = ioapic->redirtbl[irq];
202                 level ^= entry.fields.polarity;
203                 if (!level)
204                         ioapic->irr &= ~mask;
205                 else {
206                         int edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
207                         ioapic->irr |= mask;
208                         if ((edge && old_irr != ioapic->irr) ||
209                             (!edge && !entry.fields.remote_irr))
210                                 ret = ioapic_service(ioapic, irq);
211                         else
212                                 ret = 0; /* report coalesced interrupt */
213                 }
214                 trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
215         }
216         mutex_unlock(&ioapic->lock);
217
218         return ret;
219 }
220
221 static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int vector,
222                                      int trigger_mode)
223 {
224         int i;
225
226         for (i = 0; i < IOAPIC_NUM_PINS; i++) {
227                 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
228
229                 if (ent->fields.vector != vector)
230                         continue;
231
232                 /*
233                  * We are dropping lock while calling ack notifiers because ack
234                  * notifier callbacks for assigned devices call into IOAPIC
235                  * recursively. Since remote_irr is cleared only after call
236                  * to notifiers if the same vector will be delivered while lock
237                  * is dropped it will be put into irr and will be delivered
238                  * after ack notifier returns.
239                  */
240                 mutex_unlock(&ioapic->lock);
241                 kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
242                 mutex_lock(&ioapic->lock);
243
244                 if (trigger_mode != IOAPIC_LEVEL_TRIG)
245                         continue;
246
247                 ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
248                 ent->fields.remote_irr = 0;
249                 if (!ent->fields.mask && (ioapic->irr & (1 << i)))
250                         ioapic_service(ioapic, i);
251         }
252 }
253
254 void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
255 {
256         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
257
258         smp_rmb();
259         if (!test_bit(vector, ioapic->handled_vectors))
260                 return;
261         mutex_lock(&ioapic->lock);
262         __kvm_ioapic_update_eoi(ioapic, vector, trigger_mode);
263         mutex_unlock(&ioapic->lock);
264 }
265
266 static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
267 {
268         return container_of(dev, struct kvm_ioapic, dev);
269 }
270
271 static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
272 {
273         return ((addr >= ioapic->base_address &&
274                  (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
275 }
276
277 static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
278                             void *val)
279 {
280         struct kvm_ioapic *ioapic = to_ioapic(this);
281         u32 result;
282         if (!ioapic_in_range(ioapic, addr))
283                 return -EOPNOTSUPP;
284
285         ioapic_debug("addr %lx\n", (unsigned long)addr);
286         ASSERT(!(addr & 0xf));  /* check alignment */
287
288         addr &= 0xff;
289         mutex_lock(&ioapic->lock);
290         switch (addr) {
291         case IOAPIC_REG_SELECT:
292                 result = ioapic->ioregsel;
293                 break;
294
295         case IOAPIC_REG_WINDOW:
296                 result = ioapic_read_indirect(ioapic, addr, len);
297                 break;
298
299         default:
300                 result = 0;
301                 break;
302         }
303         mutex_unlock(&ioapic->lock);
304
305         switch (len) {
306         case 8:
307                 *(u64 *) val = result;
308                 break;
309         case 1:
310         case 2:
311         case 4:
312                 memcpy(val, (char *)&result, len);
313                 break;
314         default:
315                 printk(KERN_WARNING "ioapic: wrong length %d\n", len);
316         }
317         return 0;
318 }
319
320 static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
321                              const void *val)
322 {
323         struct kvm_ioapic *ioapic = to_ioapic(this);
324         u32 data;
325         if (!ioapic_in_range(ioapic, addr))
326                 return -EOPNOTSUPP;
327
328         ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
329                      (void*)addr, len, val);
330         ASSERT(!(addr & 0xf));  /* check alignment */
331
332         if (len == 4 || len == 8)
333                 data = *(u32 *) val;
334         else {
335                 printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
336                 return 0;
337         }
338
339         addr &= 0xff;
340         mutex_lock(&ioapic->lock);
341         switch (addr) {
342         case IOAPIC_REG_SELECT:
343                 ioapic->ioregsel = data;
344                 break;
345
346         case IOAPIC_REG_WINDOW:
347                 ioapic_write_indirect(ioapic, data);
348                 break;
349 #ifdef  CONFIG_IA64
350         case IOAPIC_REG_EOI:
351                 __kvm_ioapic_update_eoi(ioapic, data, IOAPIC_LEVEL_TRIG);
352                 break;
353 #endif
354
355         default:
356                 break;
357         }
358         mutex_unlock(&ioapic->lock);
359         return 0;
360 }
361
362 void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
363 {
364         int i;
365
366         for (i = 0; i < IOAPIC_NUM_PINS; i++)
367                 ioapic->redirtbl[i].fields.mask = 1;
368         ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
369         ioapic->ioregsel = 0;
370         ioapic->irr = 0;
371         ioapic->id = 0;
372         update_handled_vectors(ioapic);
373 }
374
375 static const struct kvm_io_device_ops ioapic_mmio_ops = {
376         .read     = ioapic_mmio_read,
377         .write    = ioapic_mmio_write,
378 };
379
380 int kvm_ioapic_init(struct kvm *kvm)
381 {
382         struct kvm_ioapic *ioapic;
383         int ret;
384
385         ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
386         if (!ioapic)
387                 return -ENOMEM;
388         mutex_init(&ioapic->lock);
389         kvm->arch.vioapic = ioapic;
390         kvm_ioapic_reset(ioapic);
391         kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
392         ioapic->kvm = kvm;
393         mutex_lock(&kvm->slots_lock);
394         ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
395         mutex_unlock(&kvm->slots_lock);
396         if (ret < 0) {
397                 kvm->arch.vioapic = NULL;
398                 kfree(ioapic);
399         }
400
401         return ret;
402 }
403
404 void kvm_ioapic_destroy(struct kvm *kvm)
405 {
406         struct kvm_ioapic *ioapic = kvm->arch.vioapic;
407
408         if (ioapic) {
409                 kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
410                 kvm->arch.vioapic = NULL;
411                 kfree(ioapic);
412         }
413 }
414
415 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
416 {
417         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
418         if (!ioapic)
419                 return -EINVAL;
420
421         mutex_lock(&ioapic->lock);
422         memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
423         mutex_unlock(&ioapic->lock);
424         return 0;
425 }
426
427 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
428 {
429         struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
430         if (!ioapic)
431                 return -EINVAL;
432
433         mutex_lock(&ioapic->lock);
434         memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
435         update_handled_vectors(ioapic);
436         mutex_unlock(&ioapic->lock);
437         return 0;
438 }