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 38 #include "ioapic.h" 39 #include "irq.h" 40 #include "i8254.h" 41 #include "x86.h" 42 43 #ifndef CONFIG_X86_64 44 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) 45 #else 46 #define mod_64(x, y) ((x) % (y)) 47 #endif 48 49 #define RW_STATE_LSB 1 50 #define RW_STATE_MSB 2 51 #define RW_STATE_WORD0 3 52 #define RW_STATE_WORD1 4 53 54 static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val) 55 { 56 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 57 58 switch (c->mode) { 59 default: 60 case 0: 61 case 4: 62 /* XXX: just disable/enable counting */ 63 break; 64 case 1: 65 case 2: 66 case 3: 67 case 5: 68 /* Restart counting on rising edge. */ 69 if (c->gate < val) 70 c->count_load_time = ktime_get(); 71 break; 72 } 73 74 c->gate = val; 75 } 76 77 static int pit_get_gate(struct kvm_pit *pit, int channel) 78 { 79 return pit->pit_state.channels[channel].gate; 80 } 81 82 static s64 __kpit_elapsed(struct kvm_pit *pit) 83 { 84 s64 elapsed; 85 ktime_t remaining; 86 struct kvm_kpit_state *ps = &pit->pit_state; 87 88 if (!ps->period) 89 return 0; 90 91 /* 92 * The Counter does not stop when it reaches zero. In 93 * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to 94 * the highest count, either FFFF hex for binary counting 95 * or 9999 for BCD counting, and continues counting. 96 * Modes 2 and 3 are periodic; the Counter reloads 97 * itself with the initial count and continues counting 98 * from there. 99 */ 100 remaining = hrtimer_get_remaining(&ps->timer); 101 elapsed = ps->period - ktime_to_ns(remaining); 102 103 return elapsed; 104 } 105 106 static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c, 107 int channel) 108 { 109 if (channel == 0) 110 return __kpit_elapsed(pit); 111 112 return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); 113 } 114 115 static int pit_get_count(struct kvm_pit *pit, int channel) 116 { 117 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 118 s64 d, t; 119 int counter; 120 121 t = kpit_elapsed(pit, c, channel); 122 d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC); 123 124 switch (c->mode) { 125 case 0: 126 case 1: 127 case 4: 128 case 5: 129 counter = (c->count - d) & 0xffff; 130 break; 131 case 3: 132 /* XXX: may be incorrect for odd counts */ 133 counter = c->count - (mod_64((2 * d), c->count)); 134 break; 135 default: 136 counter = c->count - mod_64(d, c->count); 137 break; 138 } 139 return counter; 140 } 141 142 static int pit_get_out(struct kvm_pit *pit, int channel) 143 { 144 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 145 s64 d, t; 146 int out; 147 148 t = kpit_elapsed(pit, c, channel); 149 d = mul_u64_u32_div(t, KVM_PIT_FREQ, NSEC_PER_SEC); 150 151 switch (c->mode) { 152 default: 153 case 0: 154 out = (d >= c->count); 155 break; 156 case 1: 157 out = (d < c->count); 158 break; 159 case 2: 160 out = ((mod_64(d, c->count) == 0) && (d != 0)); 161 break; 162 case 3: 163 out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); 164 break; 165 case 4: 166 case 5: 167 out = (d == c->count); 168 break; 169 } 170 171 return out; 172 } 173 174 static void pit_latch_count(struct kvm_pit *pit, int channel) 175 { 176 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 177 178 if (!c->count_latched) { 179 c->latched_count = pit_get_count(pit, channel); 180 c->count_latched = c->rw_mode; 181 } 182 } 183 184 static void pit_latch_status(struct kvm_pit *pit, int channel) 185 { 186 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 187 188 if (!c->status_latched) { 189 /* TODO: Return NULL COUNT (bit 6). */ 190 c->status = ((pit_get_out(pit, channel) << 7) | 191 (c->rw_mode << 4) | 192 (c->mode << 1) | 193 c->bcd); 194 c->status_latched = 1; 195 } 196 } 197 198 static inline struct kvm_pit *pit_state_to_pit(struct kvm_kpit_state *ps) 199 { 200 return container_of(ps, struct kvm_pit, pit_state); 201 } 202 203 static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 204 { 205 struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, 206 irq_ack_notifier); 207 struct kvm_pit *pit = pit_state_to_pit(ps); 208 209 atomic_set(&ps->irq_ack, 1); 210 /* irq_ack should be set before pending is read. Order accesses with 211 * inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work. 212 */ 213 smp_mb(); 214 if (atomic_dec_if_positive(&ps->pending) > 0) 215 queue_kthread_work(&pit->worker, &pit->expired); 216 } 217 218 void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 219 { 220 struct kvm_pit *pit = vcpu->kvm->arch.vpit; 221 struct hrtimer *timer; 222 223 if (!kvm_vcpu_is_bsp(vcpu) || !pit) 224 return; 225 226 timer = &pit->pit_state.timer; 227 mutex_lock(&pit->pit_state.lock); 228 if (hrtimer_cancel(timer)) 229 hrtimer_start_expires(timer, HRTIMER_MODE_ABS); 230 mutex_unlock(&pit->pit_state.lock); 231 } 232 233 static void destroy_pit_timer(struct kvm_pit *pit) 234 { 235 hrtimer_cancel(&pit->pit_state.timer); 236 flush_kthread_work(&pit->expired); 237 } 238 239 static void pit_do_work(struct kthread_work *work) 240 { 241 struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); 242 struct kvm *kvm = pit->kvm; 243 struct kvm_vcpu *vcpu; 244 int i; 245 struct kvm_kpit_state *ps = &pit->pit_state; 246 247 if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0)) 248 return; 249 250 kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false); 251 kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false); 252 253 /* 254 * Provides NMI watchdog support via Virtual Wire mode. 255 * The route is: PIT -> LVT0 in NMI mode. 256 * 257 * Note: Our Virtual Wire implementation does not follow 258 * the MP specification. We propagate a PIT interrupt to all 259 * VCPUs and only when LVT0 is in NMI mode. The interrupt can 260 * also be simultaneously delivered through PIC and IOAPIC. 261 */ 262 if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0) 263 kvm_for_each_vcpu(i, vcpu, kvm) 264 kvm_apic_nmi_wd_deliver(vcpu); 265 } 266 267 static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 268 { 269 struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer); 270 struct kvm_pit *pt = pit_state_to_pit(ps); 271 272 if (atomic_read(&ps->reinject)) 273 atomic_inc(&ps->pending); 274 275 queue_kthread_work(&pt->worker, &pt->expired); 276 277 if (ps->is_periodic) { 278 hrtimer_add_expires_ns(&ps->timer, ps->period); 279 return HRTIMER_RESTART; 280 } else 281 return HRTIMER_NORESTART; 282 } 283 284 static inline void kvm_pit_reset_reinject(struct kvm_pit *pit) 285 { 286 atomic_set(&pit->pit_state.pending, 0); 287 atomic_set(&pit->pit_state.irq_ack, 1); 288 } 289 290 void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject) 291 { 292 struct kvm_kpit_state *ps = &pit->pit_state; 293 struct kvm *kvm = pit->kvm; 294 295 if (atomic_read(&ps->reinject) == reinject) 296 return; 297 298 if (reinject) { 299 /* The initial state is preserved while ps->reinject == 0. */ 300 kvm_pit_reset_reinject(pit); 301 kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 302 kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 303 } else { 304 kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 305 kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 306 } 307 308 atomic_set(&ps->reinject, reinject); 309 } 310 311 static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period) 312 { 313 struct kvm_kpit_state *ps = &pit->pit_state; 314 struct kvm *kvm = pit->kvm; 315 s64 interval; 316 317 if (!ioapic_in_kernel(kvm) || 318 ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) 319 return; 320 321 interval = mul_u64_u32_div(val, NSEC_PER_SEC, KVM_PIT_FREQ); 322 323 pr_debug("create pit timer, interval is %llu nsec\n", interval); 324 325 /* TODO The new value only affected after the retriggered */ 326 hrtimer_cancel(&ps->timer); 327 flush_kthread_work(&pit->expired); 328 ps->period = interval; 329 ps->is_periodic = is_period; 330 331 kvm_pit_reset_reinject(pit); 332 333 /* 334 * Do not allow the guest to program periodic timers with small 335 * interval, since the hrtimers are not throttled by the host 336 * scheduler. 337 */ 338 if (ps->is_periodic) { 339 s64 min_period = min_timer_period_us * 1000LL; 340 341 if (ps->period < min_period) { 342 pr_info_ratelimited( 343 "kvm: requested %lld ns " 344 "i8254 timer period limited to %lld ns\n", 345 ps->period, min_period); 346 ps->period = min_period; 347 } 348 } 349 350 hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), 351 HRTIMER_MODE_ABS); 352 } 353 354 static void pit_load_count(struct kvm_pit *pit, int channel, u32 val) 355 { 356 struct kvm_kpit_state *ps = &pit->pit_state; 357 358 pr_debug("load_count val is %d, channel is %d\n", val, channel); 359 360 /* 361 * The largest possible initial count is 0; this is equivalent 362 * to 216 for binary counting and 104 for BCD counting. 363 */ 364 if (val == 0) 365 val = 0x10000; 366 367 ps->channels[channel].count = val; 368 369 if (channel != 0) { 370 ps->channels[channel].count_load_time = ktime_get(); 371 return; 372 } 373 374 /* Two types of timer 375 * mode 1 is one shot, mode 2 is period, otherwise del timer */ 376 switch (ps->channels[0].mode) { 377 case 0: 378 case 1: 379 /* FIXME: enhance mode 4 precision */ 380 case 4: 381 create_pit_timer(pit, val, 0); 382 break; 383 case 2: 384 case 3: 385 create_pit_timer(pit, val, 1); 386 break; 387 default: 388 destroy_pit_timer(pit); 389 } 390 } 391 392 void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val, 393 int hpet_legacy_start) 394 { 395 u8 saved_mode; 396 397 WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock)); 398 399 if (hpet_legacy_start) { 400 /* save existing mode for later reenablement */ 401 WARN_ON(channel != 0); 402 saved_mode = pit->pit_state.channels[0].mode; 403 pit->pit_state.channels[0].mode = 0xff; /* disable timer */ 404 pit_load_count(pit, channel, val); 405 pit->pit_state.channels[0].mode = saved_mode; 406 } else { 407 pit_load_count(pit, channel, val); 408 } 409 } 410 411 static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev) 412 { 413 return container_of(dev, struct kvm_pit, dev); 414 } 415 416 static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev) 417 { 418 return container_of(dev, struct kvm_pit, speaker_dev); 419 } 420 421 static inline int pit_in_range(gpa_t addr) 422 { 423 return ((addr >= KVM_PIT_BASE_ADDRESS) && 424 (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH)); 425 } 426 427 static int pit_ioport_write(struct kvm_vcpu *vcpu, 428 struct kvm_io_device *this, 429 gpa_t addr, int len, const void *data) 430 { 431 struct kvm_pit *pit = dev_to_pit(this); 432 struct kvm_kpit_state *pit_state = &pit->pit_state; 433 int channel, access; 434 struct kvm_kpit_channel_state *s; 435 u32 val = *(u32 *) data; 436 if (!pit_in_range(addr)) 437 return -EOPNOTSUPP; 438 439 val &= 0xff; 440 addr &= KVM_PIT_CHANNEL_MASK; 441 442 mutex_lock(&pit_state->lock); 443 444 if (val != 0) 445 pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n", 446 (unsigned int)addr, len, val); 447 448 if (addr == 3) { 449 channel = val >> 6; 450 if (channel == 3) { 451 /* Read-Back Command. */ 452 for (channel = 0; channel < 3; channel++) { 453 s = &pit_state->channels[channel]; 454 if (val & (2 << channel)) { 455 if (!(val & 0x20)) 456 pit_latch_count(pit, channel); 457 if (!(val & 0x10)) 458 pit_latch_status(pit, channel); 459 } 460 } 461 } else { 462 /* Select Counter <channel>. */ 463 s = &pit_state->channels[channel]; 464 access = (val >> 4) & KVM_PIT_CHANNEL_MASK; 465 if (access == 0) { 466 pit_latch_count(pit, channel); 467 } else { 468 s->rw_mode = access; 469 s->read_state = access; 470 s->write_state = access; 471 s->mode = (val >> 1) & 7; 472 if (s->mode > 5) 473 s->mode -= 4; 474 s->bcd = val & 1; 475 } 476 } 477 } else { 478 /* Write Count. */ 479 s = &pit_state->channels[addr]; 480 switch (s->write_state) { 481 default: 482 case RW_STATE_LSB: 483 pit_load_count(pit, addr, val); 484 break; 485 case RW_STATE_MSB: 486 pit_load_count(pit, addr, val << 8); 487 break; 488 case RW_STATE_WORD0: 489 s->write_latch = val; 490 s->write_state = RW_STATE_WORD1; 491 break; 492 case RW_STATE_WORD1: 493 pit_load_count(pit, addr, s->write_latch | (val << 8)); 494 s->write_state = RW_STATE_WORD0; 495 break; 496 } 497 } 498 499 mutex_unlock(&pit_state->lock); 500 return 0; 501 } 502 503 static int pit_ioport_read(struct kvm_vcpu *vcpu, 504 struct kvm_io_device *this, 505 gpa_t addr, int len, void *data) 506 { 507 struct kvm_pit *pit = dev_to_pit(this); 508 struct kvm_kpit_state *pit_state = &pit->pit_state; 509 int ret, count; 510 struct kvm_kpit_channel_state *s; 511 if (!pit_in_range(addr)) 512 return -EOPNOTSUPP; 513 514 addr &= KVM_PIT_CHANNEL_MASK; 515 if (addr == 3) 516 return 0; 517 518 s = &pit_state->channels[addr]; 519 520 mutex_lock(&pit_state->lock); 521 522 if (s->status_latched) { 523 s->status_latched = 0; 524 ret = s->status; 525 } else if (s->count_latched) { 526 switch (s->count_latched) { 527 default: 528 case RW_STATE_LSB: 529 ret = s->latched_count & 0xff; 530 s->count_latched = 0; 531 break; 532 case RW_STATE_MSB: 533 ret = s->latched_count >> 8; 534 s->count_latched = 0; 535 break; 536 case RW_STATE_WORD0: 537 ret = s->latched_count & 0xff; 538 s->count_latched = RW_STATE_MSB; 539 break; 540 } 541 } else { 542 switch (s->read_state) { 543 default: 544 case RW_STATE_LSB: 545 count = pit_get_count(pit, addr); 546 ret = count & 0xff; 547 break; 548 case RW_STATE_MSB: 549 count = pit_get_count(pit, addr); 550 ret = (count >> 8) & 0xff; 551 break; 552 case RW_STATE_WORD0: 553 count = pit_get_count(pit, addr); 554 ret = count & 0xff; 555 s->read_state = RW_STATE_WORD1; 556 break; 557 case RW_STATE_WORD1: 558 count = pit_get_count(pit, addr); 559 ret = (count >> 8) & 0xff; 560 s->read_state = RW_STATE_WORD0; 561 break; 562 } 563 } 564 565 if (len > sizeof(ret)) 566 len = sizeof(ret); 567 memcpy(data, (char *)&ret, len); 568 569 mutex_unlock(&pit_state->lock); 570 return 0; 571 } 572 573 static int speaker_ioport_write(struct kvm_vcpu *vcpu, 574 struct kvm_io_device *this, 575 gpa_t addr, int len, const void *data) 576 { 577 struct kvm_pit *pit = speaker_to_pit(this); 578 struct kvm_kpit_state *pit_state = &pit->pit_state; 579 u32 val = *(u32 *) data; 580 if (addr != KVM_SPEAKER_BASE_ADDRESS) 581 return -EOPNOTSUPP; 582 583 mutex_lock(&pit_state->lock); 584 pit_state->speaker_data_on = (val >> 1) & 1; 585 pit_set_gate(pit, 2, val & 1); 586 mutex_unlock(&pit_state->lock); 587 return 0; 588 } 589 590 static int speaker_ioport_read(struct kvm_vcpu *vcpu, 591 struct kvm_io_device *this, 592 gpa_t addr, int len, void *data) 593 { 594 struct kvm_pit *pit = speaker_to_pit(this); 595 struct kvm_kpit_state *pit_state = &pit->pit_state; 596 unsigned int refresh_clock; 597 int ret; 598 if (addr != KVM_SPEAKER_BASE_ADDRESS) 599 return -EOPNOTSUPP; 600 601 /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */ 602 refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1; 603 604 mutex_lock(&pit_state->lock); 605 ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(pit, 2) | 606 (pit_get_out(pit, 2) << 5) | (refresh_clock << 4)); 607 if (len > sizeof(ret)) 608 len = sizeof(ret); 609 memcpy(data, (char *)&ret, len); 610 mutex_unlock(&pit_state->lock); 611 return 0; 612 } 613 614 static void kvm_pit_reset(struct kvm_pit *pit) 615 { 616 int i; 617 struct kvm_kpit_channel_state *c; 618 619 pit->pit_state.flags = 0; 620 for (i = 0; i < 3; i++) { 621 c = &pit->pit_state.channels[i]; 622 c->mode = 0xff; 623 c->gate = (i != 2); 624 pit_load_count(pit, i, 0); 625 } 626 627 kvm_pit_reset_reinject(pit); 628 } 629 630 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) 631 { 632 struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); 633 634 if (!mask) 635 kvm_pit_reset_reinject(pit); 636 } 637 638 static const struct kvm_io_device_ops pit_dev_ops = { 639 .read = pit_ioport_read, 640 .write = pit_ioport_write, 641 }; 642 643 static const struct kvm_io_device_ops speaker_dev_ops = { 644 .read = speaker_ioport_read, 645 .write = speaker_ioport_write, 646 }; 647 648 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 649 { 650 struct kvm_pit *pit; 651 struct kvm_kpit_state *pit_state; 652 struct pid *pid; 653 pid_t pid_nr; 654 int ret; 655 656 pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); 657 if (!pit) 658 return NULL; 659 660 pit->irq_source_id = kvm_request_irq_source_id(kvm); 661 if (pit->irq_source_id < 0) 662 goto fail_request; 663 664 mutex_init(&pit->pit_state.lock); 665 666 pid = get_pid(task_tgid(current)); 667 pid_nr = pid_vnr(pid); 668 put_pid(pid); 669 670 init_kthread_worker(&pit->worker); 671 pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker, 672 "kvm-pit/%d", pid_nr); 673 if (IS_ERR(pit->worker_task)) 674 goto fail_kthread; 675 676 init_kthread_work(&pit->expired, pit_do_work); 677 678 pit->kvm = kvm; 679 680 pit_state = &pit->pit_state; 681 hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 682 pit_state->timer.function = pit_timer_fn; 683 684 pit_state->irq_ack_notifier.gsi = 0; 685 pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; 686 pit->mask_notifier.func = pit_mask_notifer; 687 688 kvm_pit_reset(pit); 689 690 kvm_pit_set_reinject(pit, true); 691 692 mutex_lock(&kvm->slots_lock); 693 kvm_iodevice_init(&pit->dev, &pit_dev_ops); 694 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, 695 KVM_PIT_MEM_LENGTH, &pit->dev); 696 if (ret < 0) 697 goto fail_register_pit; 698 699 if (flags & KVM_PIT_SPEAKER_DUMMY) { 700 kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); 701 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 702 KVM_SPEAKER_BASE_ADDRESS, 4, 703 &pit->speaker_dev); 704 if (ret < 0) 705 goto fail_register_speaker; 706 } 707 mutex_unlock(&kvm->slots_lock); 708 709 return pit; 710 711 fail_register_speaker: 712 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 713 fail_register_pit: 714 mutex_unlock(&kvm->slots_lock); 715 kvm_pit_set_reinject(pit, false); 716 kthread_stop(pit->worker_task); 717 fail_kthread: 718 kvm_free_irq_source_id(kvm, pit->irq_source_id); 719 fail_request: 720 kfree(pit); 721 return NULL; 722 } 723 724 void kvm_free_pit(struct kvm *kvm) 725 { 726 struct kvm_pit *pit = kvm->arch.vpit; 727 728 if (pit) { 729 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 730 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev); 731 kvm_pit_set_reinject(pit, false); 732 hrtimer_cancel(&pit->pit_state.timer); 733 flush_kthread_work(&pit->expired); 734 kthread_stop(pit->worker_task); 735 kvm_free_irq_source_id(kvm, pit->irq_source_id); 736 kfree(pit); 737 } 738 } 739