1 /* 2 * 8253/8254 interval timer emulation 3 * 4 * Copyright (c) 2003-2004 Fabrice Bellard 5 * Copyright (c) 2006 Intel Corporation 6 * Copyright (c) 2007 Keir Fraser, XenSource Inc 7 * Copyright (c) 2008 Intel Corporation 8 * Copyright 2009 Red Hat, Inc. and/or its affiliates. 9 * 10 * Permission is hereby granted, free of charge, to any person obtaining a copy 11 * of this software and associated documentation files (the "Software"), to deal 12 * in the Software without restriction, including without limitation the rights 13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 14 * copies of the Software, and to permit persons to whom the Software is 15 * furnished to do so, subject to the following conditions: 16 * 17 * The above copyright notice and this permission notice shall be included in 18 * all copies or substantial portions of the Software. 19 * 20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 26 * THE SOFTWARE. 27 * 28 * Authors: 29 * Sheng Yang <sheng.yang@intel.com> 30 * Based on QEMU and Xen. 31 */ 32 33 #define pr_fmt(fmt) "pit: " fmt 34 35 #include <linux/kvm_host.h> 36 #include <linux/slab.h> 37 #include <linux/workqueue.h> 38 39 #include "irq.h" 40 #include "i8254.h" 41 42 #ifndef CONFIG_X86_64 43 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) 44 #else 45 #define mod_64(x, y) ((x) % (y)) 46 #endif 47 48 #define RW_STATE_LSB 1 49 #define RW_STATE_MSB 2 50 #define RW_STATE_WORD0 3 51 #define RW_STATE_WORD1 4 52 53 /* Compute with 96 bit intermediate result: (a*b)/c */ 54 static u64 muldiv64(u64 a, u32 b, u32 c) 55 { 56 union { 57 u64 ll; 58 struct { 59 u32 low, high; 60 } l; 61 } u, res; 62 u64 rl, rh; 63 64 u.ll = a; 65 rl = (u64)u.l.low * (u64)b; 66 rh = (u64)u.l.high * (u64)b; 67 rh += (rl >> 32); 68 res.l.high = div64_u64(rh, c); 69 res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c); 70 return res.ll; 71 } 72 73 static void pit_set_gate(struct kvm *kvm, int channel, u32 val) 74 { 75 struct kvm_kpit_channel_state *c = 76 &kvm->arch.vpit->pit_state.channels[channel]; 77 78 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 79 80 switch (c->mode) { 81 default: 82 case 0: 83 case 4: 84 /* XXX: just disable/enable counting */ 85 break; 86 case 1: 87 case 2: 88 case 3: 89 case 5: 90 /* Restart counting on rising edge. */ 91 if (c->gate < val) 92 c->count_load_time = ktime_get(); 93 break; 94 } 95 96 c->gate = val; 97 } 98 99 static int pit_get_gate(struct kvm *kvm, int channel) 100 { 101 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 102 103 return kvm->arch.vpit->pit_state.channels[channel].gate; 104 } 105 106 static s64 __kpit_elapsed(struct kvm *kvm) 107 { 108 s64 elapsed; 109 ktime_t remaining; 110 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 111 112 if (!ps->pit_timer.period) 113 return 0; 114 115 /* 116 * The Counter does not stop when it reaches zero. In 117 * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to 118 * the highest count, either FFFF hex for binary counting 119 * or 9999 for BCD counting, and continues counting. 120 * Modes 2 and 3 are periodic; the Counter reloads 121 * itself with the initial count and continues counting 122 * from there. 123 */ 124 remaining = hrtimer_get_remaining(&ps->pit_timer.timer); 125 elapsed = ps->pit_timer.period - ktime_to_ns(remaining); 126 elapsed = mod_64(elapsed, ps->pit_timer.period); 127 128 return elapsed; 129 } 130 131 static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c, 132 int channel) 133 { 134 if (channel == 0) 135 return __kpit_elapsed(kvm); 136 137 return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); 138 } 139 140 static int pit_get_count(struct kvm *kvm, int channel) 141 { 142 struct kvm_kpit_channel_state *c = 143 &kvm->arch.vpit->pit_state.channels[channel]; 144 s64 d, t; 145 int counter; 146 147 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 148 149 t = kpit_elapsed(kvm, c, channel); 150 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 151 152 switch (c->mode) { 153 case 0: 154 case 1: 155 case 4: 156 case 5: 157 counter = (c->count - d) & 0xffff; 158 break; 159 case 3: 160 /* XXX: may be incorrect for odd counts */ 161 counter = c->count - (mod_64((2 * d), c->count)); 162 break; 163 default: 164 counter = c->count - mod_64(d, c->count); 165 break; 166 } 167 return counter; 168 } 169 170 static int pit_get_out(struct kvm *kvm, int channel) 171 { 172 struct kvm_kpit_channel_state *c = 173 &kvm->arch.vpit->pit_state.channels[channel]; 174 s64 d, t; 175 int out; 176 177 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 178 179 t = kpit_elapsed(kvm, c, channel); 180 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 181 182 switch (c->mode) { 183 default: 184 case 0: 185 out = (d >= c->count); 186 break; 187 case 1: 188 out = (d < c->count); 189 break; 190 case 2: 191 out = ((mod_64(d, c->count) == 0) && (d != 0)); 192 break; 193 case 3: 194 out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); 195 break; 196 case 4: 197 case 5: 198 out = (d == c->count); 199 break; 200 } 201 202 return out; 203 } 204 205 static void pit_latch_count(struct kvm *kvm, int channel) 206 { 207 struct kvm_kpit_channel_state *c = 208 &kvm->arch.vpit->pit_state.channels[channel]; 209 210 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 211 212 if (!c->count_latched) { 213 c->latched_count = pit_get_count(kvm, channel); 214 c->count_latched = c->rw_mode; 215 } 216 } 217 218 static void pit_latch_status(struct kvm *kvm, int channel) 219 { 220 struct kvm_kpit_channel_state *c = 221 &kvm->arch.vpit->pit_state.channels[channel]; 222 223 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 224 225 if (!c->status_latched) { 226 /* TODO: Return NULL COUNT (bit 6). */ 227 c->status = ((pit_get_out(kvm, channel) << 7) | 228 (c->rw_mode << 4) | 229 (c->mode << 1) | 230 c->bcd); 231 c->status_latched = 1; 232 } 233 } 234 235 static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 236 { 237 struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, 238 irq_ack_notifier); 239 int value; 240 241 spin_lock(&ps->inject_lock); 242 value = atomic_dec_return(&ps->pit_timer.pending); 243 if (value < 0) 244 /* spurious acks can be generated if, for example, the 245 * PIC is being reset. Handle it gracefully here 246 */ 247 atomic_inc(&ps->pit_timer.pending); 248 else if (value > 0) 249 /* in this case, we had multiple outstanding pit interrupts 250 * that we needed to inject. Reinject 251 */ 252 queue_work(ps->pit->wq, &ps->pit->expired); 253 ps->irq_ack = 1; 254 spin_unlock(&ps->inject_lock); 255 } 256 257 void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 258 { 259 struct kvm_pit *pit = vcpu->kvm->arch.vpit; 260 struct hrtimer *timer; 261 262 if (!kvm_vcpu_is_bsp(vcpu) || !pit) 263 return; 264 265 timer = &pit->pit_state.pit_timer.timer; 266 if (hrtimer_cancel(timer)) 267 hrtimer_start_expires(timer, HRTIMER_MODE_ABS); 268 } 269 270 static void destroy_pit_timer(struct kvm_pit *pit) 271 { 272 hrtimer_cancel(&pit->pit_state.pit_timer.timer); 273 cancel_work_sync(&pit->expired); 274 } 275 276 static bool kpit_is_periodic(struct kvm_timer *ktimer) 277 { 278 struct kvm_kpit_state *ps = container_of(ktimer, struct kvm_kpit_state, 279 pit_timer); 280 return ps->is_periodic; 281 } 282 283 static struct kvm_timer_ops kpit_ops = { 284 .is_periodic = kpit_is_periodic, 285 }; 286 287 static void pit_do_work(struct work_struct *work) 288 { 289 struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); 290 struct kvm *kvm = pit->kvm; 291 struct kvm_vcpu *vcpu; 292 int i; 293 struct kvm_kpit_state *ps = &pit->pit_state; 294 int inject = 0; 295 296 /* Try to inject pending interrupts when 297 * last one has been acked. 298 */ 299 spin_lock(&ps->inject_lock); 300 if (ps->irq_ack) { 301 ps->irq_ack = 0; 302 inject = 1; 303 } 304 spin_unlock(&ps->inject_lock); 305 if (inject) { 306 kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1); 307 kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0); 308 309 /* 310 * Provides NMI watchdog support via Virtual Wire mode. 311 * The route is: PIT -> PIC -> LVT0 in NMI mode. 312 * 313 * Note: Our Virtual Wire implementation is simplified, only 314 * propagating PIT interrupts to all VCPUs when they have set 315 * LVT0 to NMI delivery. Other PIC interrupts are just sent to 316 * VCPU0, and only if its LVT0 is in EXTINT mode. 317 */ 318 if (kvm->arch.vapics_in_nmi_mode > 0) 319 kvm_for_each_vcpu(i, vcpu, kvm) 320 kvm_apic_nmi_wd_deliver(vcpu); 321 } 322 } 323 324 static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 325 { 326 struct kvm_timer *ktimer = container_of(data, struct kvm_timer, timer); 327 struct kvm_pit *pt = ktimer->kvm->arch.vpit; 328 329 if (ktimer->reinject || !atomic_read(&ktimer->pending)) { 330 atomic_inc(&ktimer->pending); 331 queue_work(pt->wq, &pt->expired); 332 } 333 334 if (ktimer->t_ops->is_periodic(ktimer)) { 335 hrtimer_add_expires_ns(&ktimer->timer, ktimer->period); 336 return HRTIMER_RESTART; 337 } else 338 return HRTIMER_NORESTART; 339 } 340 341 static void create_pit_timer(struct kvm *kvm, u32 val, int is_period) 342 { 343 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 344 struct kvm_timer *pt = &ps->pit_timer; 345 s64 interval; 346 347 if (!irqchip_in_kernel(kvm) || ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) 348 return; 349 350 interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ); 351 352 pr_debug("create pit timer, interval is %llu nsec\n", interval); 353 354 /* TODO The new value only affected after the retriggered */ 355 hrtimer_cancel(&pt->timer); 356 cancel_work_sync(&ps->pit->expired); 357 pt->period = interval; 358 ps->is_periodic = is_period; 359 360 pt->timer.function = pit_timer_fn; 361 pt->t_ops = &kpit_ops; 362 pt->kvm = ps->pit->kvm; 363 364 atomic_set(&pt->pending, 0); 365 ps->irq_ack = 1; 366 367 hrtimer_start(&pt->timer, ktime_add_ns(ktime_get(), interval), 368 HRTIMER_MODE_ABS); 369 } 370 371 static void pit_load_count(struct kvm *kvm, int channel, u32 val) 372 { 373 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 374 375 WARN_ON(!mutex_is_locked(&ps->lock)); 376 377 pr_debug("load_count val is %d, channel is %d\n", val, channel); 378 379 /* 380 * The largest possible initial count is 0; this is equivalent 381 * to 216 for binary counting and 104 for BCD counting. 382 */ 383 if (val == 0) 384 val = 0x10000; 385 386 ps->channels[channel].count = val; 387 388 if (channel != 0) { 389 ps->channels[channel].count_load_time = ktime_get(); 390 return; 391 } 392 393 /* Two types of timer 394 * mode 1 is one shot, mode 2 is period, otherwise del timer */ 395 switch (ps->channels[0].mode) { 396 case 0: 397 case 1: 398 /* FIXME: enhance mode 4 precision */ 399 case 4: 400 create_pit_timer(kvm, val, 0); 401 break; 402 case 2: 403 case 3: 404 create_pit_timer(kvm, val, 1); 405 break; 406 default: 407 destroy_pit_timer(kvm->arch.vpit); 408 } 409 } 410 411 void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start) 412 { 413 u8 saved_mode; 414 if (hpet_legacy_start) { 415 /* save existing mode for later reenablement */ 416 saved_mode = kvm->arch.vpit->pit_state.channels[0].mode; 417 kvm->arch.vpit->pit_state.channels[0].mode = 0xff; /* disable timer */ 418 pit_load_count(kvm, channel, val); 419 kvm->arch.vpit->pit_state.channels[0].mode = saved_mode; 420 } else { 421 pit_load_count(kvm, channel, val); 422 } 423 } 424 425 static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev) 426 { 427 return container_of(dev, struct kvm_pit, dev); 428 } 429 430 static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev) 431 { 432 return container_of(dev, struct kvm_pit, speaker_dev); 433 } 434 435 static inline int pit_in_range(gpa_t addr) 436 { 437 return ((addr >= KVM_PIT_BASE_ADDRESS) && 438 (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH)); 439 } 440 441 static int pit_ioport_write(struct kvm_io_device *this, 442 gpa_t addr, int len, const void *data) 443 { 444 struct kvm_pit *pit = dev_to_pit(this); 445 struct kvm_kpit_state *pit_state = &pit->pit_state; 446 struct kvm *kvm = pit->kvm; 447 int channel, access; 448 struct kvm_kpit_channel_state *s; 449 u32 val = *(u32 *) data; 450 if (!pit_in_range(addr)) 451 return -EOPNOTSUPP; 452 453 val &= 0xff; 454 addr &= KVM_PIT_CHANNEL_MASK; 455 456 mutex_lock(&pit_state->lock); 457 458 if (val != 0) 459 pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n", 460 (unsigned int)addr, len, val); 461 462 if (addr == 3) { 463 channel = val >> 6; 464 if (channel == 3) { 465 /* Read-Back Command. */ 466 for (channel = 0; channel < 3; channel++) { 467 s = &pit_state->channels[channel]; 468 if (val & (2 << channel)) { 469 if (!(val & 0x20)) 470 pit_latch_count(kvm, channel); 471 if (!(val & 0x10)) 472 pit_latch_status(kvm, channel); 473 } 474 } 475 } else { 476 /* Select Counter <channel>. */ 477 s = &pit_state->channels[channel]; 478 access = (val >> 4) & KVM_PIT_CHANNEL_MASK; 479 if (access == 0) { 480 pit_latch_count(kvm, channel); 481 } else { 482 s->rw_mode = access; 483 s->read_state = access; 484 s->write_state = access; 485 s->mode = (val >> 1) & 7; 486 if (s->mode > 5) 487 s->mode -= 4; 488 s->bcd = val & 1; 489 } 490 } 491 } else { 492 /* Write Count. */ 493 s = &pit_state->channels[addr]; 494 switch (s->write_state) { 495 default: 496 case RW_STATE_LSB: 497 pit_load_count(kvm, addr, val); 498 break; 499 case RW_STATE_MSB: 500 pit_load_count(kvm, addr, val << 8); 501 break; 502 case RW_STATE_WORD0: 503 s->write_latch = val; 504 s->write_state = RW_STATE_WORD1; 505 break; 506 case RW_STATE_WORD1: 507 pit_load_count(kvm, addr, s->write_latch | (val << 8)); 508 s->write_state = RW_STATE_WORD0; 509 break; 510 } 511 } 512 513 mutex_unlock(&pit_state->lock); 514 return 0; 515 } 516 517 static int pit_ioport_read(struct kvm_io_device *this, 518 gpa_t addr, int len, void *data) 519 { 520 struct kvm_pit *pit = dev_to_pit(this); 521 struct kvm_kpit_state *pit_state = &pit->pit_state; 522 struct kvm *kvm = pit->kvm; 523 int ret, count; 524 struct kvm_kpit_channel_state *s; 525 if (!pit_in_range(addr)) 526 return -EOPNOTSUPP; 527 528 addr &= KVM_PIT_CHANNEL_MASK; 529 if (addr == 3) 530 return 0; 531 532 s = &pit_state->channels[addr]; 533 534 mutex_lock(&pit_state->lock); 535 536 if (s->status_latched) { 537 s->status_latched = 0; 538 ret = s->status; 539 } else if (s->count_latched) { 540 switch (s->count_latched) { 541 default: 542 case RW_STATE_LSB: 543 ret = s->latched_count & 0xff; 544 s->count_latched = 0; 545 break; 546 case RW_STATE_MSB: 547 ret = s->latched_count >> 8; 548 s->count_latched = 0; 549 break; 550 case RW_STATE_WORD0: 551 ret = s->latched_count & 0xff; 552 s->count_latched = RW_STATE_MSB; 553 break; 554 } 555 } else { 556 switch (s->read_state) { 557 default: 558 case RW_STATE_LSB: 559 count = pit_get_count(kvm, addr); 560 ret = count & 0xff; 561 break; 562 case RW_STATE_MSB: 563 count = pit_get_count(kvm, addr); 564 ret = (count >> 8) & 0xff; 565 break; 566 case RW_STATE_WORD0: 567 count = pit_get_count(kvm, addr); 568 ret = count & 0xff; 569 s->read_state = RW_STATE_WORD1; 570 break; 571 case RW_STATE_WORD1: 572 count = pit_get_count(kvm, addr); 573 ret = (count >> 8) & 0xff; 574 s->read_state = RW_STATE_WORD0; 575 break; 576 } 577 } 578 579 if (len > sizeof(ret)) 580 len = sizeof(ret); 581 memcpy(data, (char *)&ret, len); 582 583 mutex_unlock(&pit_state->lock); 584 return 0; 585 } 586 587 static int speaker_ioport_write(struct kvm_io_device *this, 588 gpa_t addr, int len, const void *data) 589 { 590 struct kvm_pit *pit = speaker_to_pit(this); 591 struct kvm_kpit_state *pit_state = &pit->pit_state; 592 struct kvm *kvm = pit->kvm; 593 u32 val = *(u32 *) data; 594 if (addr != KVM_SPEAKER_BASE_ADDRESS) 595 return -EOPNOTSUPP; 596 597 mutex_lock(&pit_state->lock); 598 pit_state->speaker_data_on = (val >> 1) & 1; 599 pit_set_gate(kvm, 2, val & 1); 600 mutex_unlock(&pit_state->lock); 601 return 0; 602 } 603 604 static int speaker_ioport_read(struct kvm_io_device *this, 605 gpa_t addr, int len, void *data) 606 { 607 struct kvm_pit *pit = speaker_to_pit(this); 608 struct kvm_kpit_state *pit_state = &pit->pit_state; 609 struct kvm *kvm = pit->kvm; 610 unsigned int refresh_clock; 611 int ret; 612 if (addr != KVM_SPEAKER_BASE_ADDRESS) 613 return -EOPNOTSUPP; 614 615 /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */ 616 refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1; 617 618 mutex_lock(&pit_state->lock); 619 ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(kvm, 2) | 620 (pit_get_out(kvm, 2) << 5) | (refresh_clock << 4)); 621 if (len > sizeof(ret)) 622 len = sizeof(ret); 623 memcpy(data, (char *)&ret, len); 624 mutex_unlock(&pit_state->lock); 625 return 0; 626 } 627 628 void kvm_pit_reset(struct kvm_pit *pit) 629 { 630 int i; 631 struct kvm_kpit_channel_state *c; 632 633 mutex_lock(&pit->pit_state.lock); 634 pit->pit_state.flags = 0; 635 for (i = 0; i < 3; i++) { 636 c = &pit->pit_state.channels[i]; 637 c->mode = 0xff; 638 c->gate = (i != 2); 639 pit_load_count(pit->kvm, i, 0); 640 } 641 mutex_unlock(&pit->pit_state.lock); 642 643 atomic_set(&pit->pit_state.pit_timer.pending, 0); 644 pit->pit_state.irq_ack = 1; 645 } 646 647 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) 648 { 649 struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); 650 651 if (!mask) { 652 atomic_set(&pit->pit_state.pit_timer.pending, 0); 653 pit->pit_state.irq_ack = 1; 654 } 655 } 656 657 static const struct kvm_io_device_ops pit_dev_ops = { 658 .read = pit_ioport_read, 659 .write = pit_ioport_write, 660 }; 661 662 static const struct kvm_io_device_ops speaker_dev_ops = { 663 .read = speaker_ioport_read, 664 .write = speaker_ioport_write, 665 }; 666 667 /* Caller must hold slots_lock */ 668 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 669 { 670 struct kvm_pit *pit; 671 struct kvm_kpit_state *pit_state; 672 int ret; 673 674 pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); 675 if (!pit) 676 return NULL; 677 678 pit->irq_source_id = kvm_request_irq_source_id(kvm); 679 if (pit->irq_source_id < 0) { 680 kfree(pit); 681 return NULL; 682 } 683 684 mutex_init(&pit->pit_state.lock); 685 mutex_lock(&pit->pit_state.lock); 686 spin_lock_init(&pit->pit_state.inject_lock); 687 688 pit->wq = create_singlethread_workqueue("kvm-pit-wq"); 689 if (!pit->wq) { 690 mutex_unlock(&pit->pit_state.lock); 691 kvm_free_irq_source_id(kvm, pit->irq_source_id); 692 kfree(pit); 693 return NULL; 694 } 695 INIT_WORK(&pit->expired, pit_do_work); 696 697 kvm->arch.vpit = pit; 698 pit->kvm = kvm; 699 700 pit_state = &pit->pit_state; 701 pit_state->pit = pit; 702 hrtimer_init(&pit_state->pit_timer.timer, 703 CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 704 pit_state->irq_ack_notifier.gsi = 0; 705 pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; 706 kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier); 707 pit_state->pit_timer.reinject = true; 708 mutex_unlock(&pit->pit_state.lock); 709 710 kvm_pit_reset(pit); 711 712 pit->mask_notifier.func = pit_mask_notifer; 713 kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 714 715 kvm_iodevice_init(&pit->dev, &pit_dev_ops); 716 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, 717 KVM_PIT_MEM_LENGTH, &pit->dev); 718 if (ret < 0) 719 goto fail; 720 721 if (flags & KVM_PIT_SPEAKER_DUMMY) { 722 kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); 723 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 724 KVM_SPEAKER_BASE_ADDRESS, 4, 725 &pit->speaker_dev); 726 if (ret < 0) 727 goto fail_unregister; 728 } 729 730 return pit; 731 732 fail_unregister: 733 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 734 735 fail: 736 kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 737 kvm_unregister_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier); 738 kvm_free_irq_source_id(kvm, pit->irq_source_id); 739 destroy_workqueue(pit->wq); 740 kfree(pit); 741 return NULL; 742 } 743 744 void kvm_free_pit(struct kvm *kvm) 745 { 746 struct hrtimer *timer; 747 748 if (kvm->arch.vpit) { 749 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &kvm->arch.vpit->dev); 750 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, 751 &kvm->arch.vpit->speaker_dev); 752 kvm_unregister_irq_mask_notifier(kvm, 0, 753 &kvm->arch.vpit->mask_notifier); 754 kvm_unregister_irq_ack_notifier(kvm, 755 &kvm->arch.vpit->pit_state.irq_ack_notifier); 756 mutex_lock(&kvm->arch.vpit->pit_state.lock); 757 timer = &kvm->arch.vpit->pit_state.pit_timer.timer; 758 hrtimer_cancel(timer); 759 cancel_work_sync(&kvm->arch.vpit->expired); 760 kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id); 761 mutex_unlock(&kvm->arch.vpit->pit_state.lock); 762 destroy_workqueue(kvm->arch.vpit->wq); 763 kfree(kvm->arch.vpit); 764 } 765 } 766