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 /* Compute with 96 bit intermediate result: (a*b)/c */ 55 static u64 muldiv64(u64 a, u32 b, u32 c) 56 { 57 union { 58 u64 ll; 59 struct { 60 u32 low, high; 61 } l; 62 } u, res; 63 u64 rl, rh; 64 65 u.ll = a; 66 rl = (u64)u.l.low * (u64)b; 67 rh = (u64)u.l.high * (u64)b; 68 rh += (rl >> 32); 69 res.l.high = div64_u64(rh, c); 70 res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c); 71 return res.ll; 72 } 73 74 static void pit_set_gate(struct kvm_pit *pit, int channel, u32 val) 75 { 76 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 77 78 switch (c->mode) { 79 default: 80 case 0: 81 case 4: 82 /* XXX: just disable/enable counting */ 83 break; 84 case 1: 85 case 2: 86 case 3: 87 case 5: 88 /* Restart counting on rising edge. */ 89 if (c->gate < val) 90 c->count_load_time = ktime_get(); 91 break; 92 } 93 94 c->gate = val; 95 } 96 97 static int pit_get_gate(struct kvm_pit *pit, int channel) 98 { 99 return pit->pit_state.channels[channel].gate; 100 } 101 102 static s64 __kpit_elapsed(struct kvm_pit *pit) 103 { 104 s64 elapsed; 105 ktime_t remaining; 106 struct kvm_kpit_state *ps = &pit->pit_state; 107 108 if (!ps->period) 109 return 0; 110 111 /* 112 * The Counter does not stop when it reaches zero. In 113 * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to 114 * the highest count, either FFFF hex for binary counting 115 * or 9999 for BCD counting, and continues counting. 116 * Modes 2 and 3 are periodic; the Counter reloads 117 * itself with the initial count and continues counting 118 * from there. 119 */ 120 remaining = hrtimer_get_remaining(&ps->timer); 121 elapsed = ps->period - ktime_to_ns(remaining); 122 123 return elapsed; 124 } 125 126 static s64 kpit_elapsed(struct kvm_pit *pit, struct kvm_kpit_channel_state *c, 127 int channel) 128 { 129 if (channel == 0) 130 return __kpit_elapsed(pit); 131 132 return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); 133 } 134 135 static int pit_get_count(struct kvm_pit *pit, int channel) 136 { 137 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 138 s64 d, t; 139 int counter; 140 141 t = kpit_elapsed(pit, c, channel); 142 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 143 144 switch (c->mode) { 145 case 0: 146 case 1: 147 case 4: 148 case 5: 149 counter = (c->count - d) & 0xffff; 150 break; 151 case 3: 152 /* XXX: may be incorrect for odd counts */ 153 counter = c->count - (mod_64((2 * d), c->count)); 154 break; 155 default: 156 counter = c->count - mod_64(d, c->count); 157 break; 158 } 159 return counter; 160 } 161 162 static int pit_get_out(struct kvm_pit *pit, int channel) 163 { 164 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 165 s64 d, t; 166 int out; 167 168 t = kpit_elapsed(pit, c, channel); 169 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 170 171 switch (c->mode) { 172 default: 173 case 0: 174 out = (d >= c->count); 175 break; 176 case 1: 177 out = (d < c->count); 178 break; 179 case 2: 180 out = ((mod_64(d, c->count) == 0) && (d != 0)); 181 break; 182 case 3: 183 out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); 184 break; 185 case 4: 186 case 5: 187 out = (d == c->count); 188 break; 189 } 190 191 return out; 192 } 193 194 static void pit_latch_count(struct kvm_pit *pit, int channel) 195 { 196 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 197 198 if (!c->count_latched) { 199 c->latched_count = pit_get_count(pit, channel); 200 c->count_latched = c->rw_mode; 201 } 202 } 203 204 static void pit_latch_status(struct kvm_pit *pit, int channel) 205 { 206 struct kvm_kpit_channel_state *c = &pit->pit_state.channels[channel]; 207 208 if (!c->status_latched) { 209 /* TODO: Return NULL COUNT (bit 6). */ 210 c->status = ((pit_get_out(pit, channel) << 7) | 211 (c->rw_mode << 4) | 212 (c->mode << 1) | 213 c->bcd); 214 c->status_latched = 1; 215 } 216 } 217 218 static inline struct kvm_pit *pit_state_to_pit(struct kvm_kpit_state *ps) 219 { 220 return container_of(ps, struct kvm_pit, pit_state); 221 } 222 223 static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 224 { 225 struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, 226 irq_ack_notifier); 227 struct kvm_pit *pit = pit_state_to_pit(ps); 228 229 atomic_set(&ps->irq_ack, 1); 230 /* irq_ack should be set before pending is read. Order accesses with 231 * inc(pending) in pit_timer_fn and xchg(irq_ack, 0) in pit_do_work. 232 */ 233 smp_mb(); 234 if (atomic_dec_if_positive(&ps->pending) > 0) 235 queue_kthread_work(&pit->worker, &pit->expired); 236 } 237 238 void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 239 { 240 struct kvm_pit *pit = vcpu->kvm->arch.vpit; 241 struct hrtimer *timer; 242 243 if (!kvm_vcpu_is_bsp(vcpu) || !pit) 244 return; 245 246 timer = &pit->pit_state.timer; 247 mutex_lock(&pit->pit_state.lock); 248 if (hrtimer_cancel(timer)) 249 hrtimer_start_expires(timer, HRTIMER_MODE_ABS); 250 mutex_unlock(&pit->pit_state.lock); 251 } 252 253 static void destroy_pit_timer(struct kvm_pit *pit) 254 { 255 hrtimer_cancel(&pit->pit_state.timer); 256 flush_kthread_work(&pit->expired); 257 } 258 259 static void pit_do_work(struct kthread_work *work) 260 { 261 struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); 262 struct kvm *kvm = pit->kvm; 263 struct kvm_vcpu *vcpu; 264 int i; 265 struct kvm_kpit_state *ps = &pit->pit_state; 266 267 if (atomic_read(&ps->reinject) && !atomic_xchg(&ps->irq_ack, 0)) 268 return; 269 270 kvm_set_irq(kvm, pit->irq_source_id, 0, 1, false); 271 kvm_set_irq(kvm, pit->irq_source_id, 0, 0, false); 272 273 /* 274 * Provides NMI watchdog support via Virtual Wire mode. 275 * The route is: PIT -> LVT0 in NMI mode. 276 * 277 * Note: Our Virtual Wire implementation does not follow 278 * the MP specification. We propagate a PIT interrupt to all 279 * VCPUs and only when LVT0 is in NMI mode. The interrupt can 280 * also be simultaneously delivered through PIC and IOAPIC. 281 */ 282 if (atomic_read(&kvm->arch.vapics_in_nmi_mode) > 0) 283 kvm_for_each_vcpu(i, vcpu, kvm) 284 kvm_apic_nmi_wd_deliver(vcpu); 285 } 286 287 static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 288 { 289 struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer); 290 struct kvm_pit *pt = pit_state_to_pit(ps); 291 292 if (atomic_read(&ps->reinject)) 293 atomic_inc(&ps->pending); 294 295 queue_kthread_work(&pt->worker, &pt->expired); 296 297 if (ps->is_periodic) { 298 hrtimer_add_expires_ns(&ps->timer, ps->period); 299 return HRTIMER_RESTART; 300 } else 301 return HRTIMER_NORESTART; 302 } 303 304 static inline void kvm_pit_reset_reinject(struct kvm_pit *pit) 305 { 306 atomic_set(&pit->pit_state.pending, 0); 307 atomic_set(&pit->pit_state.irq_ack, 1); 308 } 309 310 void kvm_pit_set_reinject(struct kvm_pit *pit, bool reinject) 311 { 312 struct kvm_kpit_state *ps = &pit->pit_state; 313 struct kvm *kvm = pit->kvm; 314 315 if (atomic_read(&ps->reinject) == reinject) 316 return; 317 318 if (reinject) { 319 /* The initial state is preserved while ps->reinject == 0. */ 320 kvm_pit_reset_reinject(pit); 321 kvm_register_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 322 kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 323 } else { 324 kvm_unregister_irq_ack_notifier(kvm, &ps->irq_ack_notifier); 325 kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 326 } 327 328 atomic_set(&ps->reinject, reinject); 329 } 330 331 static void create_pit_timer(struct kvm_pit *pit, u32 val, int is_period) 332 { 333 struct kvm_kpit_state *ps = &pit->pit_state; 334 struct kvm *kvm = pit->kvm; 335 s64 interval; 336 337 if (!ioapic_in_kernel(kvm) || 338 ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) 339 return; 340 341 interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ); 342 343 pr_debug("create pit timer, interval is %llu nsec\n", interval); 344 345 /* TODO The new value only affected after the retriggered */ 346 hrtimer_cancel(&ps->timer); 347 flush_kthread_work(&pit->expired); 348 ps->period = interval; 349 ps->is_periodic = is_period; 350 351 kvm_pit_reset_reinject(pit); 352 353 /* 354 * Do not allow the guest to program periodic timers with small 355 * interval, since the hrtimers are not throttled by the host 356 * scheduler. 357 */ 358 if (ps->is_periodic) { 359 s64 min_period = min_timer_period_us * 1000LL; 360 361 if (ps->period < min_period) { 362 pr_info_ratelimited( 363 "kvm: requested %lld ns " 364 "i8254 timer period limited to %lld ns\n", 365 ps->period, min_period); 366 ps->period = min_period; 367 } 368 } 369 370 hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), 371 HRTIMER_MODE_ABS); 372 } 373 374 static void pit_load_count(struct kvm_pit *pit, int channel, u32 val) 375 { 376 struct kvm_kpit_state *ps = &pit->pit_state; 377 378 pr_debug("load_count val is %d, channel is %d\n", val, channel); 379 380 /* 381 * The largest possible initial count is 0; this is equivalent 382 * to 216 for binary counting and 104 for BCD counting. 383 */ 384 if (val == 0) 385 val = 0x10000; 386 387 ps->channels[channel].count = val; 388 389 if (channel != 0) { 390 ps->channels[channel].count_load_time = ktime_get(); 391 return; 392 } 393 394 /* Two types of timer 395 * mode 1 is one shot, mode 2 is period, otherwise del timer */ 396 switch (ps->channels[0].mode) { 397 case 0: 398 case 1: 399 /* FIXME: enhance mode 4 precision */ 400 case 4: 401 create_pit_timer(pit, val, 0); 402 break; 403 case 2: 404 case 3: 405 create_pit_timer(pit, val, 1); 406 break; 407 default: 408 destroy_pit_timer(pit); 409 } 410 } 411 412 void kvm_pit_load_count(struct kvm_pit *pit, int channel, u32 val, 413 int hpet_legacy_start) 414 { 415 u8 saved_mode; 416 417 WARN_ON_ONCE(!mutex_is_locked(&pit->pit_state.lock)); 418 419 if (hpet_legacy_start) { 420 /* save existing mode for later reenablement */ 421 WARN_ON(channel != 0); 422 saved_mode = pit->pit_state.channels[0].mode; 423 pit->pit_state.channels[0].mode = 0xff; /* disable timer */ 424 pit_load_count(pit, channel, val); 425 pit->pit_state.channels[0].mode = saved_mode; 426 } else { 427 pit_load_count(pit, channel, val); 428 } 429 } 430 431 static inline struct kvm_pit *dev_to_pit(struct kvm_io_device *dev) 432 { 433 return container_of(dev, struct kvm_pit, dev); 434 } 435 436 static inline struct kvm_pit *speaker_to_pit(struct kvm_io_device *dev) 437 { 438 return container_of(dev, struct kvm_pit, speaker_dev); 439 } 440 441 static inline int pit_in_range(gpa_t addr) 442 { 443 return ((addr >= KVM_PIT_BASE_ADDRESS) && 444 (addr < KVM_PIT_BASE_ADDRESS + KVM_PIT_MEM_LENGTH)); 445 } 446 447 static int pit_ioport_write(struct kvm_vcpu *vcpu, 448 struct kvm_io_device *this, 449 gpa_t addr, int len, const void *data) 450 { 451 struct kvm_pit *pit = dev_to_pit(this); 452 struct kvm_kpit_state *pit_state = &pit->pit_state; 453 int channel, access; 454 struct kvm_kpit_channel_state *s; 455 u32 val = *(u32 *) data; 456 if (!pit_in_range(addr)) 457 return -EOPNOTSUPP; 458 459 val &= 0xff; 460 addr &= KVM_PIT_CHANNEL_MASK; 461 462 mutex_lock(&pit_state->lock); 463 464 if (val != 0) 465 pr_debug("write addr is 0x%x, len is %d, val is 0x%x\n", 466 (unsigned int)addr, len, val); 467 468 if (addr == 3) { 469 channel = val >> 6; 470 if (channel == 3) { 471 /* Read-Back Command. */ 472 for (channel = 0; channel < 3; channel++) { 473 s = &pit_state->channels[channel]; 474 if (val & (2 << channel)) { 475 if (!(val & 0x20)) 476 pit_latch_count(pit, channel); 477 if (!(val & 0x10)) 478 pit_latch_status(pit, channel); 479 } 480 } 481 } else { 482 /* Select Counter <channel>. */ 483 s = &pit_state->channels[channel]; 484 access = (val >> 4) & KVM_PIT_CHANNEL_MASK; 485 if (access == 0) { 486 pit_latch_count(pit, channel); 487 } else { 488 s->rw_mode = access; 489 s->read_state = access; 490 s->write_state = access; 491 s->mode = (val >> 1) & 7; 492 if (s->mode > 5) 493 s->mode -= 4; 494 s->bcd = val & 1; 495 } 496 } 497 } else { 498 /* Write Count. */ 499 s = &pit_state->channels[addr]; 500 switch (s->write_state) { 501 default: 502 case RW_STATE_LSB: 503 pit_load_count(pit, addr, val); 504 break; 505 case RW_STATE_MSB: 506 pit_load_count(pit, addr, val << 8); 507 break; 508 case RW_STATE_WORD0: 509 s->write_latch = val; 510 s->write_state = RW_STATE_WORD1; 511 break; 512 case RW_STATE_WORD1: 513 pit_load_count(pit, addr, s->write_latch | (val << 8)); 514 s->write_state = RW_STATE_WORD0; 515 break; 516 } 517 } 518 519 mutex_unlock(&pit_state->lock); 520 return 0; 521 } 522 523 static int pit_ioport_read(struct kvm_vcpu *vcpu, 524 struct kvm_io_device *this, 525 gpa_t addr, int len, void *data) 526 { 527 struct kvm_pit *pit = dev_to_pit(this); 528 struct kvm_kpit_state *pit_state = &pit->pit_state; 529 int ret, count; 530 struct kvm_kpit_channel_state *s; 531 if (!pit_in_range(addr)) 532 return -EOPNOTSUPP; 533 534 addr &= KVM_PIT_CHANNEL_MASK; 535 if (addr == 3) 536 return 0; 537 538 s = &pit_state->channels[addr]; 539 540 mutex_lock(&pit_state->lock); 541 542 if (s->status_latched) { 543 s->status_latched = 0; 544 ret = s->status; 545 } else if (s->count_latched) { 546 switch (s->count_latched) { 547 default: 548 case RW_STATE_LSB: 549 ret = s->latched_count & 0xff; 550 s->count_latched = 0; 551 break; 552 case RW_STATE_MSB: 553 ret = s->latched_count >> 8; 554 s->count_latched = 0; 555 break; 556 case RW_STATE_WORD0: 557 ret = s->latched_count & 0xff; 558 s->count_latched = RW_STATE_MSB; 559 break; 560 } 561 } else { 562 switch (s->read_state) { 563 default: 564 case RW_STATE_LSB: 565 count = pit_get_count(pit, addr); 566 ret = count & 0xff; 567 break; 568 case RW_STATE_MSB: 569 count = pit_get_count(pit, addr); 570 ret = (count >> 8) & 0xff; 571 break; 572 case RW_STATE_WORD0: 573 count = pit_get_count(pit, addr); 574 ret = count & 0xff; 575 s->read_state = RW_STATE_WORD1; 576 break; 577 case RW_STATE_WORD1: 578 count = pit_get_count(pit, addr); 579 ret = (count >> 8) & 0xff; 580 s->read_state = RW_STATE_WORD0; 581 break; 582 } 583 } 584 585 if (len > sizeof(ret)) 586 len = sizeof(ret); 587 memcpy(data, (char *)&ret, len); 588 589 mutex_unlock(&pit_state->lock); 590 return 0; 591 } 592 593 static int speaker_ioport_write(struct kvm_vcpu *vcpu, 594 struct kvm_io_device *this, 595 gpa_t addr, int len, const void *data) 596 { 597 struct kvm_pit *pit = speaker_to_pit(this); 598 struct kvm_kpit_state *pit_state = &pit->pit_state; 599 u32 val = *(u32 *) data; 600 if (addr != KVM_SPEAKER_BASE_ADDRESS) 601 return -EOPNOTSUPP; 602 603 mutex_lock(&pit_state->lock); 604 pit_state->speaker_data_on = (val >> 1) & 1; 605 pit_set_gate(pit, 2, val & 1); 606 mutex_unlock(&pit_state->lock); 607 return 0; 608 } 609 610 static int speaker_ioport_read(struct kvm_vcpu *vcpu, 611 struct kvm_io_device *this, 612 gpa_t addr, int len, void *data) 613 { 614 struct kvm_pit *pit = speaker_to_pit(this); 615 struct kvm_kpit_state *pit_state = &pit->pit_state; 616 unsigned int refresh_clock; 617 int ret; 618 if (addr != KVM_SPEAKER_BASE_ADDRESS) 619 return -EOPNOTSUPP; 620 621 /* Refresh clock toggles at about 15us. We approximate as 2^14ns. */ 622 refresh_clock = ((unsigned int)ktime_to_ns(ktime_get()) >> 14) & 1; 623 624 mutex_lock(&pit_state->lock); 625 ret = ((pit_state->speaker_data_on << 1) | pit_get_gate(pit, 2) | 626 (pit_get_out(pit, 2) << 5) | (refresh_clock << 4)); 627 if (len > sizeof(ret)) 628 len = sizeof(ret); 629 memcpy(data, (char *)&ret, len); 630 mutex_unlock(&pit_state->lock); 631 return 0; 632 } 633 634 static void kvm_pit_reset(struct kvm_pit *pit) 635 { 636 int i; 637 struct kvm_kpit_channel_state *c; 638 639 pit->pit_state.flags = 0; 640 for (i = 0; i < 3; i++) { 641 c = &pit->pit_state.channels[i]; 642 c->mode = 0xff; 643 c->gate = (i != 2); 644 pit_load_count(pit, i, 0); 645 } 646 647 kvm_pit_reset_reinject(pit); 648 } 649 650 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) 651 { 652 struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); 653 654 if (!mask) 655 kvm_pit_reset_reinject(pit); 656 } 657 658 static const struct kvm_io_device_ops pit_dev_ops = { 659 .read = pit_ioport_read, 660 .write = pit_ioport_write, 661 }; 662 663 static const struct kvm_io_device_ops speaker_dev_ops = { 664 .read = speaker_ioport_read, 665 .write = speaker_ioport_write, 666 }; 667 668 /* Caller must hold slots_lock */ 669 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 670 { 671 struct kvm_pit *pit; 672 struct kvm_kpit_state *pit_state; 673 struct pid *pid; 674 pid_t pid_nr; 675 int ret; 676 677 pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); 678 if (!pit) 679 return NULL; 680 681 pit->irq_source_id = kvm_request_irq_source_id(kvm); 682 if (pit->irq_source_id < 0) 683 goto fail_request; 684 685 mutex_init(&pit->pit_state.lock); 686 687 pid = get_pid(task_tgid(current)); 688 pid_nr = pid_vnr(pid); 689 put_pid(pid); 690 691 init_kthread_worker(&pit->worker); 692 pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker, 693 "kvm-pit/%d", pid_nr); 694 if (IS_ERR(pit->worker_task)) 695 goto fail_kthread; 696 697 init_kthread_work(&pit->expired, pit_do_work); 698 699 pit->kvm = kvm; 700 701 pit_state = &pit->pit_state; 702 hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 703 pit_state->timer.function = pit_timer_fn; 704 705 pit_state->irq_ack_notifier.gsi = 0; 706 pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; 707 pit->mask_notifier.func = pit_mask_notifer; 708 709 kvm_pit_reset(pit); 710 711 kvm_pit_set_reinject(pit, true); 712 713 kvm_iodevice_init(&pit->dev, &pit_dev_ops); 714 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, 715 KVM_PIT_MEM_LENGTH, &pit->dev); 716 if (ret < 0) 717 goto fail_register_pit; 718 719 if (flags & KVM_PIT_SPEAKER_DUMMY) { 720 kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); 721 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 722 KVM_SPEAKER_BASE_ADDRESS, 4, 723 &pit->speaker_dev); 724 if (ret < 0) 725 goto fail_register_speaker; 726 } 727 728 return pit; 729 730 fail_register_speaker: 731 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 732 fail_register_pit: 733 kvm_pit_set_reinject(pit, false); 734 kthread_stop(pit->worker_task); 735 fail_kthread: 736 kvm_free_irq_source_id(kvm, pit->irq_source_id); 737 fail_request: 738 kfree(pit); 739 return NULL; 740 } 741 742 void kvm_free_pit(struct kvm *kvm) 743 { 744 struct kvm_pit *pit = kvm->arch.vpit; 745 746 if (pit) { 747 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 748 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->speaker_dev); 749 kvm_pit_set_reinject(pit, false); 750 hrtimer_cancel(&pit->pit_state.timer); 751 flush_kthread_work(&pit->expired); 752 kthread_stop(pit->worker_task); 753 kvm_free_irq_source_id(kvm, pit->irq_source_id); 754 kfree(pit); 755 } 756 } 757