1 /*
2 * Copyright (C) 2001 MandrakeSoft S.A.
3 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
4 *
5 * MandrakeSoft S.A.
6 * 43, rue d'Aboukir
7 * 75002 Paris - France
8 * http://www.linux-mandrake.com/
9 * http://www.mandrakesoft.com/
10 *
11 * This library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation; either
14 * version 2 of the License, or (at your option) any later version.
15 *
16 * This library is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this library; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 *
25 * Yunhong Jiang <yunhong.jiang@intel.com>
26 * Yaozu (Eddie) Dong <eddie.dong@intel.com>
27 * Based on Xen 3.1 code.
28 */
29
30 #include <linux/kvm_host.h>
31 #include <linux/kvm.h>
32 #include <linux/mm.h>
33 #include <linux/highmem.h>
34 #include <linux/smp.h>
35 #include <linux/hrtimer.h>
36 #include <linux/io.h>
37 #include <linux/slab.h>
38 #include <asm/processor.h>
39 #include <asm/page.h>
40 #include <asm/current.h>
41 #include <trace/events/kvm.h>
42
43 #include "ioapic.h"
44 #include "lapic.h"
45 #include "irq.h"
46
47 #if 0
48 #define ioapic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg)
49 #else
50 #define ioapic_debug(fmt, arg...)
51 #endif
52 static int ioapic_deliver(struct kvm_ioapic *vioapic, int irq);
53
ioapic_read_indirect(struct kvm_ioapic * ioapic,unsigned long addr,unsigned long length)54 static unsigned long ioapic_read_indirect(struct kvm_ioapic *ioapic,
55 unsigned long addr,
56 unsigned long length)
57 {
58 unsigned long result = 0;
59
60 switch (ioapic->ioregsel) {
61 case IOAPIC_REG_VERSION:
62 result = ((((IOAPIC_NUM_PINS - 1) & 0xff) << 16)
63 | (IOAPIC_VERSION_ID & 0xff));
64 break;
65
66 case IOAPIC_REG_APIC_ID:
67 case IOAPIC_REG_ARB_ID:
68 result = ((ioapic->id & 0xf) << 24);
69 break;
70
71 default:
72 {
73 u32 redir_index = (ioapic->ioregsel - 0x10) >> 1;
74 u64 redir_content;
75
76 ASSERT(redir_index < IOAPIC_NUM_PINS);
77
78 redir_content = ioapic->redirtbl[redir_index].bits;
79 result = (ioapic->ioregsel & 0x1) ?
80 (redir_content >> 32) & 0xffffffff :
81 redir_content & 0xffffffff;
82 break;
83 }
84 }
85
86 return result;
87 }
88
ioapic_service(struct kvm_ioapic * ioapic,unsigned int idx)89 static int ioapic_service(struct kvm_ioapic *ioapic, unsigned int idx)
90 {
91 union kvm_ioapic_redirect_entry *pent;
92 int injected = -1;
93
94 pent = &ioapic->redirtbl[idx];
95
96 if (!pent->fields.mask) {
97 injected = ioapic_deliver(ioapic, idx);
98 if (injected && pent->fields.trig_mode == IOAPIC_LEVEL_TRIG)
99 pent->fields.remote_irr = 1;
100 }
101
102 return injected;
103 }
104
update_handled_vectors(struct kvm_ioapic * ioapic)105 static void update_handled_vectors(struct kvm_ioapic *ioapic)
106 {
107 DECLARE_BITMAP(handled_vectors, 256);
108 int i;
109
110 memset(handled_vectors, 0, sizeof(handled_vectors));
111 for (i = 0; i < IOAPIC_NUM_PINS; ++i)
112 __set_bit(ioapic->redirtbl[i].fields.vector, handled_vectors);
113 memcpy(ioapic->handled_vectors, handled_vectors,
114 sizeof(handled_vectors));
115 smp_wmb();
116 }
117
ioapic_write_indirect(struct kvm_ioapic * ioapic,u32 val)118 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
119 {
120 unsigned index;
121 bool mask_before, mask_after;
122 union kvm_ioapic_redirect_entry *e;
123
124 switch (ioapic->ioregsel) {
125 case IOAPIC_REG_VERSION:
126 /* Writes are ignored. */
127 break;
128
129 case IOAPIC_REG_APIC_ID:
130 ioapic->id = (val >> 24) & 0xf;
131 break;
132
133 case IOAPIC_REG_ARB_ID:
134 break;
135
136 default:
137 index = (ioapic->ioregsel - 0x10) >> 1;
138
139 ioapic_debug("change redir index %x val %x\n", index, val);
140 if (index >= IOAPIC_NUM_PINS)
141 return;
142 e = &ioapic->redirtbl[index];
143 mask_before = e->fields.mask;
144 if (ioapic->ioregsel & 1) {
145 e->bits &= 0xffffffff;
146 e->bits |= (u64) val << 32;
147 } else {
148 e->bits &= ~0xffffffffULL;
149 e->bits |= (u32) val;
150 e->fields.remote_irr = 0;
151 }
152 update_handled_vectors(ioapic);
153 mask_after = e->fields.mask;
154 if (mask_before != mask_after)
155 kvm_fire_mask_notifiers(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index, mask_after);
156 if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
157 && ioapic->irr & (1 << index))
158 ioapic_service(ioapic, index);
159 break;
160 }
161 }
162
ioapic_deliver(struct kvm_ioapic * ioapic,int irq)163 static int ioapic_deliver(struct kvm_ioapic *ioapic, int irq)
164 {
165 union kvm_ioapic_redirect_entry *entry = &ioapic->redirtbl[irq];
166 struct kvm_lapic_irq irqe;
167
168 ioapic_debug("dest=%x dest_mode=%x delivery_mode=%x "
169 "vector=%x trig_mode=%x\n",
170 entry->fields.dest, entry->fields.dest_mode,
171 entry->fields.delivery_mode, entry->fields.vector,
172 entry->fields.trig_mode);
173
174 irqe.dest_id = entry->fields.dest_id;
175 irqe.vector = entry->fields.vector;
176 irqe.dest_mode = entry->fields.dest_mode;
177 irqe.trig_mode = entry->fields.trig_mode;
178 irqe.delivery_mode = entry->fields.delivery_mode << 8;
179 irqe.level = 1;
180 irqe.shorthand = 0;
181
182 #ifdef CONFIG_X86
183 /* Always delivery PIT interrupt to vcpu 0 */
184 if (irq == 0) {
185 irqe.dest_mode = 0; /* Physical mode. */
186 /* need to read apic_id from apic regiest since
187 * it can be rewritten */
188 irqe.dest_id = ioapic->kvm->bsp_vcpu->vcpu_id;
189 }
190 #endif
191 return kvm_irq_delivery_to_apic(ioapic->kvm, NULL, &irqe);
192 }
193
kvm_ioapic_set_irq(struct kvm_ioapic * ioapic,int irq,int level)194 int kvm_ioapic_set_irq(struct kvm_ioapic *ioapic, int irq, int level)
195 {
196 u32 old_irr;
197 u32 mask = 1 << irq;
198 union kvm_ioapic_redirect_entry entry;
199 int ret = 1;
200
201 spin_lock(&ioapic->lock);
202 old_irr = ioapic->irr;
203 if (irq >= 0 && irq < IOAPIC_NUM_PINS) {
204 entry = ioapic->redirtbl[irq];
205 level ^= entry.fields.polarity;
206 if (!level)
207 ioapic->irr &= ~mask;
208 else {
209 int edge = (entry.fields.trig_mode == IOAPIC_EDGE_TRIG);
210 ioapic->irr |= mask;
211 if ((edge && old_irr != ioapic->irr) ||
212 (!edge && !entry.fields.remote_irr))
213 ret = ioapic_service(ioapic, irq);
214 else
215 ret = 0; /* report coalesced interrupt */
216 }
217 trace_kvm_ioapic_set_irq(entry.bits, irq, ret == 0);
218 }
219 spin_unlock(&ioapic->lock);
220
221 return ret;
222 }
223
__kvm_ioapic_update_eoi(struct kvm_ioapic * ioapic,int vector,int trigger_mode)224 static void __kvm_ioapic_update_eoi(struct kvm_ioapic *ioapic, int vector,
225 int trigger_mode)
226 {
227 int i;
228
229 for (i = 0; i < IOAPIC_NUM_PINS; i++) {
230 union kvm_ioapic_redirect_entry *ent = &ioapic->redirtbl[i];
231
232 if (ent->fields.vector != vector)
233 continue;
234
235 /*
236 * We are dropping lock while calling ack notifiers because ack
237 * notifier callbacks for assigned devices call into IOAPIC
238 * recursively. Since remote_irr is cleared only after call
239 * to notifiers if the same vector will be delivered while lock
240 * is dropped it will be put into irr and will be delivered
241 * after ack notifier returns.
242 */
243 spin_unlock(&ioapic->lock);
244 kvm_notify_acked_irq(ioapic->kvm, KVM_IRQCHIP_IOAPIC, i);
245 spin_lock(&ioapic->lock);
246
247 if (trigger_mode != IOAPIC_LEVEL_TRIG)
248 continue;
249
250 ASSERT(ent->fields.trig_mode == IOAPIC_LEVEL_TRIG);
251 ent->fields.remote_irr = 0;
252 if (!ent->fields.mask && (ioapic->irr & (1 << i)))
253 ioapic_service(ioapic, i);
254 }
255 }
256
kvm_ioapic_update_eoi(struct kvm * kvm,int vector,int trigger_mode)257 void kvm_ioapic_update_eoi(struct kvm *kvm, int vector, int trigger_mode)
258 {
259 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
260
261 smp_rmb();
262 if (!test_bit(vector, ioapic->handled_vectors))
263 return;
264 spin_lock(&ioapic->lock);
265 __kvm_ioapic_update_eoi(ioapic, vector, trigger_mode);
266 spin_unlock(&ioapic->lock);
267 }
268
to_ioapic(struct kvm_io_device * dev)269 static inline struct kvm_ioapic *to_ioapic(struct kvm_io_device *dev)
270 {
271 return container_of(dev, struct kvm_ioapic, dev);
272 }
273
ioapic_in_range(struct kvm_ioapic * ioapic,gpa_t addr)274 static inline int ioapic_in_range(struct kvm_ioapic *ioapic, gpa_t addr)
275 {
276 return ((addr >= ioapic->base_address &&
277 (addr < ioapic->base_address + IOAPIC_MEM_LENGTH)));
278 }
279
ioapic_mmio_read(struct kvm_io_device * this,gpa_t addr,int len,void * val)280 static int ioapic_mmio_read(struct kvm_io_device *this, gpa_t addr, int len,
281 void *val)
282 {
283 struct kvm_ioapic *ioapic = to_ioapic(this);
284 u32 result;
285 if (!ioapic_in_range(ioapic, addr))
286 return -EOPNOTSUPP;
287
288 ioapic_debug("addr %lx\n", (unsigned long)addr);
289 ASSERT(!(addr & 0xf)); /* check alignment */
290
291 addr &= 0xff;
292 spin_lock(&ioapic->lock);
293 switch (addr) {
294 case IOAPIC_REG_SELECT:
295 result = ioapic->ioregsel;
296 break;
297
298 case IOAPIC_REG_WINDOW:
299 result = ioapic_read_indirect(ioapic, addr, len);
300 break;
301
302 default:
303 result = 0;
304 break;
305 }
306 spin_unlock(&ioapic->lock);
307
308 switch (len) {
309 case 8:
310 *(u64 *) val = result;
311 break;
312 case 1:
313 case 2:
314 case 4:
315 memcpy(val, (char *)&result, len);
316 break;
317 default:
318 printk(KERN_WARNING "ioapic: wrong length %d\n", len);
319 }
320 return 0;
321 }
322
ioapic_mmio_write(struct kvm_io_device * this,gpa_t addr,int len,const void * val)323 static int ioapic_mmio_write(struct kvm_io_device *this, gpa_t addr, int len,
324 const void *val)
325 {
326 struct kvm_ioapic *ioapic = to_ioapic(this);
327 u32 data;
328 if (!ioapic_in_range(ioapic, addr))
329 return -EOPNOTSUPP;
330
331 ioapic_debug("ioapic_mmio_write addr=%p len=%d val=%p\n",
332 (void*)addr, len, val);
333 ASSERT(!(addr & 0xf)); /* check alignment */
334
335 if (len == 4 || len == 8)
336 data = *(u32 *) val;
337 else {
338 printk(KERN_WARNING "ioapic: Unsupported size %d\n", len);
339 return 0;
340 }
341
342 addr &= 0xff;
343 spin_lock(&ioapic->lock);
344 switch (addr) {
345 case IOAPIC_REG_SELECT:
346 ioapic->ioregsel = data;
347 break;
348
349 case IOAPIC_REG_WINDOW:
350 ioapic_write_indirect(ioapic, data);
351 break;
352 #ifdef CONFIG_IA64
353 case IOAPIC_REG_EOI:
354 __kvm_ioapic_update_eoi(ioapic, data, IOAPIC_LEVEL_TRIG);
355 break;
356 #endif
357
358 default:
359 break;
360 }
361 spin_unlock(&ioapic->lock);
362 return 0;
363 }
364
kvm_ioapic_reset(struct kvm_ioapic * ioapic)365 void kvm_ioapic_reset(struct kvm_ioapic *ioapic)
366 {
367 int i;
368
369 for (i = 0; i < IOAPIC_NUM_PINS; i++)
370 ioapic->redirtbl[i].fields.mask = 1;
371 ioapic->base_address = IOAPIC_DEFAULT_BASE_ADDRESS;
372 ioapic->ioregsel = 0;
373 ioapic->irr = 0;
374 ioapic->id = 0;
375 update_handled_vectors(ioapic);
376 }
377
378 static const struct kvm_io_device_ops ioapic_mmio_ops = {
379 .read = ioapic_mmio_read,
380 .write = ioapic_mmio_write,
381 };
382
kvm_ioapic_init(struct kvm * kvm)383 int kvm_ioapic_init(struct kvm *kvm)
384 {
385 struct kvm_ioapic *ioapic;
386 int ret;
387
388 ioapic = kzalloc(sizeof(struct kvm_ioapic), GFP_KERNEL);
389 if (!ioapic)
390 return -ENOMEM;
391 spin_lock_init(&ioapic->lock);
392 kvm->arch.vioapic = ioapic;
393 kvm_ioapic_reset(ioapic);
394 kvm_iodevice_init(&ioapic->dev, &ioapic_mmio_ops);
395 ioapic->kvm = kvm;
396 mutex_lock(&kvm->slots_lock);
397 ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
398 mutex_unlock(&kvm->slots_lock);
399 if (ret < 0) {
400 kvm->arch.vioapic = NULL;
401 kfree(ioapic);
402 }
403
404 return ret;
405 }
406
kvm_ioapic_destroy(struct kvm * kvm)407 void kvm_ioapic_destroy(struct kvm *kvm)
408 {
409 struct kvm_ioapic *ioapic = kvm->arch.vioapic;
410
411 if (ioapic) {
412 kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &ioapic->dev);
413 kvm->arch.vioapic = NULL;
414 kfree(ioapic);
415 }
416 }
417
kvm_get_ioapic(struct kvm * kvm,struct kvm_ioapic_state * state)418 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
419 {
420 struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
421 if (!ioapic)
422 return -EINVAL;
423
424 spin_lock(&ioapic->lock);
425 memcpy(state, ioapic, sizeof(struct kvm_ioapic_state));
426 spin_unlock(&ioapic->lock);
427 return 0;
428 }
429
kvm_set_ioapic(struct kvm * kvm,struct kvm_ioapic_state * state)430 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
431 {
432 struct kvm_ioapic *ioapic = ioapic_irqchip(kvm);
433 if (!ioapic)
434 return -EINVAL;
435
436 spin_lock(&ioapic->lock);
437 memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
438 update_handled_vectors(ioapic);
439 spin_unlock(&ioapic->lock);
440 return 0;
441 }
442