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 "irq.h" 39 #include "i8254.h" 40 41 #ifndef CONFIG_X86_64 42 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y)) 43 #else 44 #define mod_64(x, y) ((x) % (y)) 45 #endif 46 47 #define RW_STATE_LSB 1 48 #define RW_STATE_MSB 2 49 #define RW_STATE_WORD0 3 50 #define RW_STATE_WORD1 4 51 52 /* Compute with 96 bit intermediate result: (a*b)/c */ 53 static u64 muldiv64(u64 a, u32 b, u32 c) 54 { 55 union { 56 u64 ll; 57 struct { 58 u32 low, high; 59 } l; 60 } u, res; 61 u64 rl, rh; 62 63 u.ll = a; 64 rl = (u64)u.l.low * (u64)b; 65 rh = (u64)u.l.high * (u64)b; 66 rh += (rl >> 32); 67 res.l.high = div64_u64(rh, c); 68 res.l.low = div64_u64(((mod_64(rh, c) << 32) + (rl & 0xffffffff)), c); 69 return res.ll; 70 } 71 72 static void pit_set_gate(struct kvm *kvm, int channel, u32 val) 73 { 74 struct kvm_kpit_channel_state *c = 75 &kvm->arch.vpit->pit_state.channels[channel]; 76 77 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 78 79 switch (c->mode) { 80 default: 81 case 0: 82 case 4: 83 /* XXX: just disable/enable counting */ 84 break; 85 case 1: 86 case 2: 87 case 3: 88 case 5: 89 /* Restart counting on rising edge. */ 90 if (c->gate < val) 91 c->count_load_time = ktime_get(); 92 break; 93 } 94 95 c->gate = val; 96 } 97 98 static int pit_get_gate(struct kvm *kvm, int channel) 99 { 100 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 101 102 return kvm->arch.vpit->pit_state.channels[channel].gate; 103 } 104 105 static s64 __kpit_elapsed(struct kvm *kvm) 106 { 107 s64 elapsed; 108 ktime_t remaining; 109 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 110 111 if (!ps->period) 112 return 0; 113 114 /* 115 * The Counter does not stop when it reaches zero. In 116 * Modes 0, 1, 4, and 5 the Counter ``wraps around'' to 117 * the highest count, either FFFF hex for binary counting 118 * or 9999 for BCD counting, and continues counting. 119 * Modes 2 and 3 are periodic; the Counter reloads 120 * itself with the initial count and continues counting 121 * from there. 122 */ 123 remaining = hrtimer_get_remaining(&ps->timer); 124 elapsed = ps->period - ktime_to_ns(remaining); 125 elapsed = mod_64(elapsed, ps->period); 126 127 return elapsed; 128 } 129 130 static s64 kpit_elapsed(struct kvm *kvm, struct kvm_kpit_channel_state *c, 131 int channel) 132 { 133 if (channel == 0) 134 return __kpit_elapsed(kvm); 135 136 return ktime_to_ns(ktime_sub(ktime_get(), c->count_load_time)); 137 } 138 139 static int pit_get_count(struct kvm *kvm, int channel) 140 { 141 struct kvm_kpit_channel_state *c = 142 &kvm->arch.vpit->pit_state.channels[channel]; 143 s64 d, t; 144 int counter; 145 146 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 147 148 t = kpit_elapsed(kvm, c, channel); 149 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 150 151 switch (c->mode) { 152 case 0: 153 case 1: 154 case 4: 155 case 5: 156 counter = (c->count - d) & 0xffff; 157 break; 158 case 3: 159 /* XXX: may be incorrect for odd counts */ 160 counter = c->count - (mod_64((2 * d), c->count)); 161 break; 162 default: 163 counter = c->count - mod_64(d, c->count); 164 break; 165 } 166 return counter; 167 } 168 169 static int pit_get_out(struct kvm *kvm, int channel) 170 { 171 struct kvm_kpit_channel_state *c = 172 &kvm->arch.vpit->pit_state.channels[channel]; 173 s64 d, t; 174 int out; 175 176 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 177 178 t = kpit_elapsed(kvm, c, channel); 179 d = muldiv64(t, KVM_PIT_FREQ, NSEC_PER_SEC); 180 181 switch (c->mode) { 182 default: 183 case 0: 184 out = (d >= c->count); 185 break; 186 case 1: 187 out = (d < c->count); 188 break; 189 case 2: 190 out = ((mod_64(d, c->count) == 0) && (d != 0)); 191 break; 192 case 3: 193 out = (mod_64(d, c->count) < ((c->count + 1) >> 1)); 194 break; 195 case 4: 196 case 5: 197 out = (d == c->count); 198 break; 199 } 200 201 return out; 202 } 203 204 static void pit_latch_count(struct kvm *kvm, int channel) 205 { 206 struct kvm_kpit_channel_state *c = 207 &kvm->arch.vpit->pit_state.channels[channel]; 208 209 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 210 211 if (!c->count_latched) { 212 c->latched_count = pit_get_count(kvm, channel); 213 c->count_latched = c->rw_mode; 214 } 215 } 216 217 static void pit_latch_status(struct kvm *kvm, int channel) 218 { 219 struct kvm_kpit_channel_state *c = 220 &kvm->arch.vpit->pit_state.channels[channel]; 221 222 WARN_ON(!mutex_is_locked(&kvm->arch.vpit->pit_state.lock)); 223 224 if (!c->status_latched) { 225 /* TODO: Return NULL COUNT (bit 6). */ 226 c->status = ((pit_get_out(kvm, channel) << 7) | 227 (c->rw_mode << 4) | 228 (c->mode << 1) | 229 c->bcd); 230 c->status_latched = 1; 231 } 232 } 233 234 static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) 235 { 236 struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, 237 irq_ack_notifier); 238 int value; 239 240 spin_lock(&ps->inject_lock); 241 value = atomic_dec_return(&ps->pending); 242 if (value < 0) 243 /* spurious acks can be generated if, for example, the 244 * PIC is being reset. Handle it gracefully here 245 */ 246 atomic_inc(&ps->pending); 247 else if (value > 0) 248 /* in this case, we had multiple outstanding pit interrupts 249 * that we needed to inject. Reinject 250 */ 251 queue_kthread_work(&ps->pit->worker, &ps->pit->expired); 252 ps->irq_ack = 1; 253 spin_unlock(&ps->inject_lock); 254 } 255 256 void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) 257 { 258 struct kvm_pit *pit = vcpu->kvm->arch.vpit; 259 struct hrtimer *timer; 260 261 if (!kvm_vcpu_is_bsp(vcpu) || !pit) 262 return; 263 264 timer = &pit->pit_state.timer; 265 if (hrtimer_cancel(timer)) 266 hrtimer_start_expires(timer, HRTIMER_MODE_ABS); 267 } 268 269 static void destroy_pit_timer(struct kvm_pit *pit) 270 { 271 hrtimer_cancel(&pit->pit_state.timer); 272 flush_kthread_work(&pit->expired); 273 } 274 275 static void pit_do_work(struct kthread_work *work) 276 { 277 struct kvm_pit *pit = container_of(work, struct kvm_pit, expired); 278 struct kvm *kvm = pit->kvm; 279 struct kvm_vcpu *vcpu; 280 int i; 281 struct kvm_kpit_state *ps = &pit->pit_state; 282 int inject = 0; 283 284 /* Try to inject pending interrupts when 285 * last one has been acked. 286 */ 287 spin_lock(&ps->inject_lock); 288 if (ps->irq_ack) { 289 ps->irq_ack = 0; 290 inject = 1; 291 } 292 spin_unlock(&ps->inject_lock); 293 if (inject) { 294 kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1); 295 kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0); 296 297 /* 298 * Provides NMI watchdog support via Virtual Wire mode. 299 * The route is: PIT -> PIC -> LVT0 in NMI mode. 300 * 301 * Note: Our Virtual Wire implementation is simplified, only 302 * propagating PIT interrupts to all VCPUs when they have set 303 * LVT0 to NMI delivery. Other PIC interrupts are just sent to 304 * VCPU0, and only if its LVT0 is in EXTINT mode. 305 */ 306 if (kvm->arch.vapics_in_nmi_mode > 0) 307 kvm_for_each_vcpu(i, vcpu, kvm) 308 kvm_apic_nmi_wd_deliver(vcpu); 309 } 310 } 311 312 static enum hrtimer_restart pit_timer_fn(struct hrtimer *data) 313 { 314 struct kvm_kpit_state *ps = container_of(data, struct kvm_kpit_state, timer); 315 struct kvm_pit *pt = ps->kvm->arch.vpit; 316 317 if (ps->reinject || !atomic_read(&ps->pending)) { 318 atomic_inc(&ps->pending); 319 queue_kthread_work(&pt->worker, &pt->expired); 320 } 321 322 if (ps->is_periodic) { 323 hrtimer_add_expires_ns(&ps->timer, ps->period); 324 return HRTIMER_RESTART; 325 } else 326 return HRTIMER_NORESTART; 327 } 328 329 static void create_pit_timer(struct kvm *kvm, u32 val, int is_period) 330 { 331 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 332 s64 interval; 333 334 if (!irqchip_in_kernel(kvm) || ps->flags & KVM_PIT_FLAGS_HPET_LEGACY) 335 return; 336 337 interval = muldiv64(val, NSEC_PER_SEC, KVM_PIT_FREQ); 338 339 pr_debug("create pit timer, interval is %llu nsec\n", interval); 340 341 /* TODO The new value only affected after the retriggered */ 342 hrtimer_cancel(&ps->timer); 343 flush_kthread_work(&ps->pit->expired); 344 ps->period = interval; 345 ps->is_periodic = is_period; 346 347 ps->timer.function = pit_timer_fn; 348 ps->kvm = ps->pit->kvm; 349 350 atomic_set(&ps->pending, 0); 351 ps->irq_ack = 1; 352 353 hrtimer_start(&ps->timer, ktime_add_ns(ktime_get(), interval), 354 HRTIMER_MODE_ABS); 355 } 356 357 static void pit_load_count(struct kvm *kvm, int channel, u32 val) 358 { 359 struct kvm_kpit_state *ps = &kvm->arch.vpit->pit_state; 360 361 WARN_ON(!mutex_is_locked(&ps->lock)); 362 363 pr_debug("load_count val is %d, channel is %d\n", val, channel); 364 365 /* 366 * The largest possible initial count is 0; this is equivalent 367 * to 216 for binary counting and 104 for BCD counting. 368 */ 369 if (val == 0) 370 val = 0x10000; 371 372 ps->channels[channel].count = val; 373 374 if (channel != 0) { 375 ps->channels[channel].count_load_time = ktime_get(); 376 return; 377 } 378 379 /* Two types of timer 380 * mode 1 is one shot, mode 2 is period, otherwise del timer */ 381 switch (ps->channels[0].mode) { 382 case 0: 383 case 1: 384 /* FIXME: enhance mode 4 precision */ 385 case 4: 386 create_pit_timer(kvm, val, 0); 387 break; 388 case 2: 389 case 3: 390 create_pit_timer(kvm, val, 1); 391 break; 392 default: 393 destroy_pit_timer(kvm->arch.vpit); 394 } 395 } 396 397 void kvm_pit_load_count(struct kvm *kvm, int channel, u32 val, int hpet_legacy_start) 398 { 399 u8 saved_mode; 400 if (hpet_legacy_start) { 401 /* save existing mode for later reenablement */ 402 saved_mode = kvm->arch.vpit->pit_state.channels[0].mode; 403 kvm->arch.vpit->pit_state.channels[0].mode = 0xff; /* disable timer */ 404 pit_load_count(kvm, channel, val); 405 kvm->arch.vpit->pit_state.channels[0].mode = saved_mode; 406 } else { 407 pit_load_count(kvm, 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_io_device *this, 428 gpa_t addr, int len, const void *data) 429 { 430 struct kvm_pit *pit = dev_to_pit(this); 431 struct kvm_kpit_state *pit_state = &pit->pit_state; 432 struct kvm *kvm = pit->kvm; 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(kvm, channel); 457 if (!(val & 0x10)) 458 pit_latch_status(kvm, 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(kvm, 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(kvm, addr, val); 484 break; 485 case RW_STATE_MSB: 486 pit_load_count(kvm, 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(kvm, 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_io_device *this, 504 gpa_t addr, int len, void *data) 505 { 506 struct kvm_pit *pit = dev_to_pit(this); 507 struct kvm_kpit_state *pit_state = &pit->pit_state; 508 struct kvm *kvm = pit->kvm; 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(kvm, addr); 546 ret = count & 0xff; 547 break; 548 case RW_STATE_MSB: 549 count = pit_get_count(kvm, addr); 550 ret = (count >> 8) & 0xff; 551 break; 552 case RW_STATE_WORD0: 553 count = pit_get_count(kvm, addr); 554 ret = count & 0xff; 555 s->read_state = RW_STATE_WORD1; 556 break; 557 case RW_STATE_WORD1: 558 count = pit_get_count(kvm, 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_io_device *this, 574 gpa_t addr, int len, const void *data) 575 { 576 struct kvm_pit *pit = speaker_to_pit(this); 577 struct kvm_kpit_state *pit_state = &pit->pit_state; 578 struct kvm *kvm = pit->kvm; 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(kvm, 2, val & 1); 586 mutex_unlock(&pit_state->lock); 587 return 0; 588 } 589 590 static int speaker_ioport_read(struct kvm_io_device *this, 591 gpa_t addr, int len, void *data) 592 { 593 struct kvm_pit *pit = speaker_to_pit(this); 594 struct kvm_kpit_state *pit_state = &pit->pit_state; 595 struct kvm *kvm = pit->kvm; 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(kvm, 2) | 606 (pit_get_out(kvm, 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 void kvm_pit_reset(struct kvm_pit *pit) 615 { 616 int i; 617 struct kvm_kpit_channel_state *c; 618 619 mutex_lock(&pit->pit_state.lock); 620 pit->pit_state.flags = 0; 621 for (i = 0; i < 3; i++) { 622 c = &pit->pit_state.channels[i]; 623 c->mode = 0xff; 624 c->gate = (i != 2); 625 pit_load_count(pit->kvm, i, 0); 626 } 627 mutex_unlock(&pit->pit_state.lock); 628 629 atomic_set(&pit->pit_state.pending, 0); 630 pit->pit_state.irq_ack = 1; 631 } 632 633 static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) 634 { 635 struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); 636 637 if (!mask) { 638 atomic_set(&pit->pit_state.pending, 0); 639 pit->pit_state.irq_ack = 1; 640 } 641 } 642 643 static const struct kvm_io_device_ops pit_dev_ops = { 644 .read = pit_ioport_read, 645 .write = pit_ioport_write, 646 }; 647 648 static const struct kvm_io_device_ops speaker_dev_ops = { 649 .read = speaker_ioport_read, 650 .write = speaker_ioport_write, 651 }; 652 653 /* Caller must hold slots_lock */ 654 struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) 655 { 656 struct kvm_pit *pit; 657 struct kvm_kpit_state *pit_state; 658 struct pid *pid; 659 pid_t pid_nr; 660 int ret; 661 662 pit = kzalloc(sizeof(struct kvm_pit), GFP_KERNEL); 663 if (!pit) 664 return NULL; 665 666 pit->irq_source_id = kvm_request_irq_source_id(kvm); 667 if (pit->irq_source_id < 0) { 668 kfree(pit); 669 return NULL; 670 } 671 672 mutex_init(&pit->pit_state.lock); 673 mutex_lock(&pit->pit_state.lock); 674 spin_lock_init(&pit->pit_state.inject_lock); 675 676 pid = get_pid(task_tgid(current)); 677 pid_nr = pid_vnr(pid); 678 put_pid(pid); 679 680 init_kthread_worker(&pit->worker); 681 pit->worker_task = kthread_run(kthread_worker_fn, &pit->worker, 682 "kvm-pit/%d", pid_nr); 683 if (IS_ERR(pit->worker_task)) { 684 mutex_unlock(&pit->pit_state.lock); 685 kvm_free_irq_source_id(kvm, pit->irq_source_id); 686 kfree(pit); 687 return NULL; 688 } 689 init_kthread_work(&pit->expired, pit_do_work); 690 691 kvm->arch.vpit = pit; 692 pit->kvm = kvm; 693 694 pit_state = &pit->pit_state; 695 pit_state->pit = pit; 696 hrtimer_init(&pit_state->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); 697 pit_state->irq_ack_notifier.gsi = 0; 698 pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; 699 kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier); 700 pit_state->reinject = true; 701 mutex_unlock(&pit->pit_state.lock); 702 703 kvm_pit_reset(pit); 704 705 pit->mask_notifier.func = pit_mask_notifer; 706 kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 707 708 kvm_iodevice_init(&pit->dev, &pit_dev_ops); 709 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, KVM_PIT_BASE_ADDRESS, 710 KVM_PIT_MEM_LENGTH, &pit->dev); 711 if (ret < 0) 712 goto fail; 713 714 if (flags & KVM_PIT_SPEAKER_DUMMY) { 715 kvm_iodevice_init(&pit->speaker_dev, &speaker_dev_ops); 716 ret = kvm_io_bus_register_dev(kvm, KVM_PIO_BUS, 717 KVM_SPEAKER_BASE_ADDRESS, 4, 718 &pit->speaker_dev); 719 if (ret < 0) 720 goto fail_unregister; 721 } 722 723 return pit; 724 725 fail_unregister: 726 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &pit->dev); 727 728 fail: 729 kvm_unregister_irq_mask_notifier(kvm, 0, &pit->mask_notifier); 730 kvm_unregister_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier); 731 kvm_free_irq_source_id(kvm, pit->irq_source_id); 732 kthread_stop(pit->worker_task); 733 kfree(pit); 734 return NULL; 735 } 736 737 void kvm_free_pit(struct kvm *kvm) 738 { 739 struct hrtimer *timer; 740 741 if (kvm->arch.vpit) { 742 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &kvm->arch.vpit->dev); 743 kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, 744 &kvm->arch.vpit->speaker_dev); 745 kvm_unregister_irq_mask_notifier(kvm, 0, 746 &kvm->arch.vpit->mask_notifier); 747 kvm_unregister_irq_ack_notifier(kvm, 748 &kvm->arch.vpit->pit_state.irq_ack_notifier); 749 mutex_lock(&kvm->arch.vpit->pit_state.lock); 750 timer = &kvm->arch.vpit->pit_state.timer; 751 hrtimer_cancel(timer); 752 flush_kthread_work(&kvm->arch.vpit->expired); 753 kthread_stop(kvm->arch.vpit->worker_task); 754 kvm_free_irq_source_id(kvm, kvm->arch.vpit->irq_source_id); 755 mutex_unlock(&kvm->arch.vpit->pit_state.lock); 756 kfree(kvm->arch.vpit); 757 } 758 } 759