1 /* $NetBSD: kfd_events.c,v 1.3 2021/12/18 23:44:59 riastradh Exp $ */ 2 3 /* 4 * Copyright 2014 Advanced Micro Devices, Inc. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the "Software"), 8 * to deal in the Software without restriction, including without limitation 9 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 10 * and/or sell copies of the Software, and to permit persons to whom the 11 * Software is furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 22 * OTHER DEALINGS IN THE SOFTWARE. 23 */ 24 25 #include <sys/cdefs.h> 26 __KERNEL_RCSID(0, "$NetBSD: kfd_events.c,v 1.3 2021/12/18 23:44:59 riastradh Exp $"); 27 28 #include <linux/mm_types.h> 29 #include <linux/slab.h> 30 #include <linux/types.h> 31 #include <linux/sched/signal.h> 32 #include <linux/sched/mm.h> 33 #include <linux/uaccess.h> 34 #include <linux/mman.h> 35 #include <linux/memory.h> 36 #include "kfd_priv.h" 37 #include "kfd_events.h" 38 #include "kfd_iommu.h" 39 #include <linux/device.h> 40 41 /* 42 * Wrapper around wait_queue_entry_t 43 */ 44 struct kfd_event_waiter { 45 wait_queue_entry_t wait; 46 struct kfd_event *event; /* Event to wait for */ 47 bool activated; /* Becomes true when event is signaled */ 48 }; 49 50 /* 51 * Each signal event needs a 64-bit signal slot where the signaler will write 52 * a 1 before sending an interrupt. (This is needed because some interrupts 53 * do not contain enough spare data bits to identify an event.) 54 * We get whole pages and map them to the process VA. 55 * Individual signal events use their event_id as slot index. 56 */ 57 struct kfd_signal_page { 58 uint64_t *kernel_address; 59 uint64_t __user *user_address; 60 bool need_to_free_pages; 61 }; 62 63 64 static uint64_t *page_slots(struct kfd_signal_page *page) 65 { 66 return page->kernel_address; 67 } 68 69 static struct kfd_signal_page *allocate_signal_page(struct kfd_process *p) 70 { 71 void *backing_store; 72 struct kfd_signal_page *page; 73 74 page = kzalloc(sizeof(*page), GFP_KERNEL); 75 if (!page) 76 return NULL; 77 78 backing_store = (void *) __get_free_pages(GFP_KERNEL, 79 get_order(KFD_SIGNAL_EVENT_LIMIT * 8)); 80 if (!backing_store) 81 goto fail_alloc_signal_store; 82 83 /* Initialize all events to unsignaled */ 84 memset(backing_store, (uint8_t) UNSIGNALED_EVENT_SLOT, 85 KFD_SIGNAL_EVENT_LIMIT * 8); 86 87 page->kernel_address = backing_store; 88 page->need_to_free_pages = true; 89 pr_debug("Allocated new event signal page at %p, for process %p\n", 90 page, p); 91 92 return page; 93 94 fail_alloc_signal_store: 95 kfree(page); 96 return NULL; 97 } 98 99 static int allocate_event_notification_slot(struct kfd_process *p, 100 struct kfd_event *ev) 101 { 102 int id; 103 104 if (!p->signal_page) { 105 p->signal_page = allocate_signal_page(p); 106 if (!p->signal_page) 107 return -ENOMEM; 108 /* Oldest user mode expects 256 event slots */ 109 p->signal_mapped_size = 256*8; 110 } 111 112 /* 113 * Compatibility with old user mode: Only use signal slots 114 * user mode has mapped, may be less than 115 * KFD_SIGNAL_EVENT_LIMIT. This also allows future increase 116 * of the event limit without breaking user mode. 117 */ 118 id = idr_alloc(&p->event_idr, ev, 0, p->signal_mapped_size / 8, 119 GFP_KERNEL); 120 if (id < 0) 121 return id; 122 123 ev->event_id = id; 124 page_slots(p->signal_page)[id] = UNSIGNALED_EVENT_SLOT; 125 126 return 0; 127 } 128 129 /* 130 * Assumes that p->event_mutex is held and of course that p is not going 131 * away (current or locked). 132 */ 133 static struct kfd_event *lookup_event_by_id(struct kfd_process *p, uint32_t id) 134 { 135 return idr_find(&p->event_idr, id); 136 } 137 138 /** 139 * lookup_signaled_event_by_partial_id - Lookup signaled event from partial ID 140 * @p: Pointer to struct kfd_process 141 * @id: ID to look up 142 * @bits: Number of valid bits in @id 143 * 144 * Finds the first signaled event with a matching partial ID. If no 145 * matching signaled event is found, returns NULL. In that case the 146 * caller should assume that the partial ID is invalid and do an 147 * exhaustive search of all siglaned events. 148 * 149 * If multiple events with the same partial ID signal at the same 150 * time, they will be found one interrupt at a time, not necessarily 151 * in the same order the interrupts occurred. As long as the number of 152 * interrupts is correct, all signaled events will be seen by the 153 * driver. 154 */ 155 static struct kfd_event *lookup_signaled_event_by_partial_id( 156 struct kfd_process *p, uint32_t id, uint32_t bits) 157 { 158 struct kfd_event *ev; 159 160 if (!p->signal_page || id >= KFD_SIGNAL_EVENT_LIMIT) 161 return NULL; 162 163 /* Fast path for the common case that @id is not a partial ID 164 * and we only need a single lookup. 165 */ 166 if (bits > 31 || (1U << bits) >= KFD_SIGNAL_EVENT_LIMIT) { 167 if (page_slots(p->signal_page)[id] == UNSIGNALED_EVENT_SLOT) 168 return NULL; 169 170 return idr_find(&p->event_idr, id); 171 } 172 173 /* General case for partial IDs: Iterate over all matching IDs 174 * and find the first one that has signaled. 175 */ 176 for (ev = NULL; id < KFD_SIGNAL_EVENT_LIMIT && !ev; id += 1U << bits) { 177 if (page_slots(p->signal_page)[id] == UNSIGNALED_EVENT_SLOT) 178 continue; 179 180 ev = idr_find(&p->event_idr, id); 181 } 182 183 return ev; 184 } 185 186 static int create_signal_event(struct file *devkfd, 187 struct kfd_process *p, 188 struct kfd_event *ev) 189 { 190 int ret; 191 192 if (p->signal_mapped_size && 193 p->signal_event_count == p->signal_mapped_size / 8) { 194 if (!p->signal_event_limit_reached) { 195 pr_warn("Signal event wasn't created because limit was reached\n"); 196 p->signal_event_limit_reached = true; 197 } 198 return -ENOSPC; 199 } 200 201 ret = allocate_event_notification_slot(p, ev); 202 if (ret) { 203 pr_warn("Signal event wasn't created because out of kernel memory\n"); 204 return ret; 205 } 206 207 p->signal_event_count++; 208 209 ev->user_signal_address = &p->signal_page->user_address[ev->event_id]; 210 pr_debug("Signal event number %zu created with id %d, address %p\n", 211 p->signal_event_count, ev->event_id, 212 ev->user_signal_address); 213 214 return 0; 215 } 216 217 static int create_other_event(struct kfd_process *p, struct kfd_event *ev) 218 { 219 /* Cast KFD_LAST_NONSIGNAL_EVENT to uint32_t. This allows an 220 * intentional integer overflow to -1 without a compiler 221 * warning. idr_alloc treats a negative value as "maximum 222 * signed integer". 223 */ 224 int id = idr_alloc(&p->event_idr, ev, KFD_FIRST_NONSIGNAL_EVENT_ID, 225 (uint32_t)KFD_LAST_NONSIGNAL_EVENT_ID + 1, 226 GFP_KERNEL); 227 228 if (id < 0) 229 return id; 230 ev->event_id = id; 231 232 return 0; 233 } 234 235 void kfd_event_init_process(struct kfd_process *p) 236 { 237 mutex_init(&p->event_mutex); 238 idr_init(&p->event_idr); 239 p->signal_page = NULL; 240 p->signal_event_count = 0; 241 } 242 243 static void destroy_event(struct kfd_process *p, struct kfd_event *ev) 244 { 245 struct kfd_event_waiter *waiter; 246 247 /* Wake up pending waiters. They will return failure */ 248 list_for_each_entry(waiter, &ev->wq.head, wait.entry) 249 waiter->event = NULL; 250 wake_up_all(&ev->wq); 251 252 if (ev->type == KFD_EVENT_TYPE_SIGNAL || 253 ev->type == KFD_EVENT_TYPE_DEBUG) 254 p->signal_event_count--; 255 256 idr_remove(&p->event_idr, ev->event_id); 257 kfree(ev); 258 } 259 260 static void destroy_events(struct kfd_process *p) 261 { 262 struct kfd_event *ev; 263 uint32_t id; 264 265 idr_for_each_entry(&p->event_idr, ev, id) 266 destroy_event(p, ev); 267 idr_destroy(&p->event_idr); 268 } 269 270 /* 271 * We assume that the process is being destroyed and there is no need to 272 * unmap the pages or keep bookkeeping data in order. 273 */ 274 static void shutdown_signal_page(struct kfd_process *p) 275 { 276 struct kfd_signal_page *page = p->signal_page; 277 278 if (page) { 279 if (page->need_to_free_pages) 280 free_pages((unsigned long)page->kernel_address, 281 get_order(KFD_SIGNAL_EVENT_LIMIT * 8)); 282 kfree(page); 283 } 284 } 285 286 void kfd_event_free_process(struct kfd_process *p) 287 { 288 destroy_events(p); 289 shutdown_signal_page(p); 290 } 291 292 static bool event_can_be_gpu_signaled(const struct kfd_event *ev) 293 { 294 return ev->type == KFD_EVENT_TYPE_SIGNAL || 295 ev->type == KFD_EVENT_TYPE_DEBUG; 296 } 297 298 static bool event_can_be_cpu_signaled(const struct kfd_event *ev) 299 { 300 return ev->type == KFD_EVENT_TYPE_SIGNAL; 301 } 302 303 int kfd_event_page_set(struct kfd_process *p, void *kernel_address, 304 uint64_t size) 305 { 306 struct kfd_signal_page *page; 307 308 if (p->signal_page) 309 return -EBUSY; 310 311 page = kzalloc(sizeof(*page), GFP_KERNEL); 312 if (!page) 313 return -ENOMEM; 314 315 /* Initialize all events to unsignaled */ 316 memset(kernel_address, (uint8_t) UNSIGNALED_EVENT_SLOT, 317 KFD_SIGNAL_EVENT_LIMIT * 8); 318 319 page->kernel_address = kernel_address; 320 321 p->signal_page = page; 322 p->signal_mapped_size = size; 323 324 return 0; 325 } 326 327 int kfd_event_create(struct file *devkfd, struct kfd_process *p, 328 uint32_t event_type, bool auto_reset, uint32_t node_id, 329 uint32_t *event_id, uint32_t *event_trigger_data, 330 uint64_t *event_page_offset, uint32_t *event_slot_index) 331 { 332 int ret = 0; 333 struct kfd_event *ev = kzalloc(sizeof(*ev), GFP_KERNEL); 334 335 if (!ev) 336 return -ENOMEM; 337 338 ev->type = event_type; 339 ev->auto_reset = auto_reset; 340 ev->signaled = false; 341 342 init_waitqueue_head(&ev->wq); 343 344 *event_page_offset = 0; 345 346 mutex_lock(&p->event_mutex); 347 348 switch (event_type) { 349 case KFD_EVENT_TYPE_SIGNAL: 350 case KFD_EVENT_TYPE_DEBUG: 351 ret = create_signal_event(devkfd, p, ev); 352 if (!ret) { 353 *event_page_offset = KFD_MMAP_TYPE_EVENTS; 354 *event_slot_index = ev->event_id; 355 } 356 break; 357 default: 358 ret = create_other_event(p, ev); 359 break; 360 } 361 362 if (!ret) { 363 *event_id = ev->event_id; 364 *event_trigger_data = ev->event_id; 365 } else { 366 kfree(ev); 367 } 368 369 mutex_unlock(&p->event_mutex); 370 371 return ret; 372 } 373 374 /* Assumes that p is current. */ 375 int kfd_event_destroy(struct kfd_process *p, uint32_t event_id) 376 { 377 struct kfd_event *ev; 378 int ret = 0; 379 380 mutex_lock(&p->event_mutex); 381 382 ev = lookup_event_by_id(p, event_id); 383 384 if (ev) 385 destroy_event(p, ev); 386 else 387 ret = -EINVAL; 388 389 mutex_unlock(&p->event_mutex); 390 return ret; 391 } 392 393 static void set_event(struct kfd_event *ev) 394 { 395 struct kfd_event_waiter *waiter; 396 397 /* Auto reset if the list is non-empty and we're waking 398 * someone. waitqueue_active is safe here because we're 399 * protected by the p->event_mutex, which is also held when 400 * updating the wait queues in kfd_wait_on_events. 401 */ 402 ev->signaled = !ev->auto_reset || !waitqueue_active(&ev->wq); 403 404 list_for_each_entry(waiter, &ev->wq.head, wait.entry) 405 waiter->activated = true; 406 407 wake_up_all(&ev->wq); 408 } 409 410 /* Assumes that p is current. */ 411 int kfd_set_event(struct kfd_process *p, uint32_t event_id) 412 { 413 int ret = 0; 414 struct kfd_event *ev; 415 416 mutex_lock(&p->event_mutex); 417 418 ev = lookup_event_by_id(p, event_id); 419 420 if (ev && event_can_be_cpu_signaled(ev)) 421 set_event(ev); 422 else 423 ret = -EINVAL; 424 425 mutex_unlock(&p->event_mutex); 426 return ret; 427 } 428 429 static void reset_event(struct kfd_event *ev) 430 { 431 ev->signaled = false; 432 } 433 434 /* Assumes that p is current. */ 435 int kfd_reset_event(struct kfd_process *p, uint32_t event_id) 436 { 437 int ret = 0; 438 struct kfd_event *ev; 439 440 mutex_lock(&p->event_mutex); 441 442 ev = lookup_event_by_id(p, event_id); 443 444 if (ev && event_can_be_cpu_signaled(ev)) 445 reset_event(ev); 446 else 447 ret = -EINVAL; 448 449 mutex_unlock(&p->event_mutex); 450 return ret; 451 452 } 453 454 static void acknowledge_signal(struct kfd_process *p, struct kfd_event *ev) 455 { 456 page_slots(p->signal_page)[ev->event_id] = UNSIGNALED_EVENT_SLOT; 457 } 458 459 static void set_event_from_interrupt(struct kfd_process *p, 460 struct kfd_event *ev) 461 { 462 if (ev && event_can_be_gpu_signaled(ev)) { 463 acknowledge_signal(p, ev); 464 set_event(ev); 465 } 466 } 467 468 void kfd_signal_event_interrupt(unsigned int pasid, uint32_t partial_id, 469 uint32_t valid_id_bits) 470 { 471 struct kfd_event *ev = NULL; 472 473 /* 474 * Because we are called from arbitrary context (workqueue) as opposed 475 * to process context, kfd_process could attempt to exit while we are 476 * running so the lookup function increments the process ref count. 477 */ 478 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid); 479 480 if (!p) 481 return; /* Presumably process exited. */ 482 483 mutex_lock(&p->event_mutex); 484 485 if (valid_id_bits) 486 ev = lookup_signaled_event_by_partial_id(p, partial_id, 487 valid_id_bits); 488 if (ev) { 489 set_event_from_interrupt(p, ev); 490 } else if (p->signal_page) { 491 /* 492 * Partial ID lookup failed. Assume that the event ID 493 * in the interrupt payload was invalid and do an 494 * exhaustive search of signaled events. 495 */ 496 uint64_t *slots = page_slots(p->signal_page); 497 uint32_t id; 498 499 if (valid_id_bits) 500 pr_debug_ratelimited("Partial ID invalid: %u (%u valid bits)\n", 501 partial_id, valid_id_bits); 502 503 if (p->signal_event_count < KFD_SIGNAL_EVENT_LIMIT / 64) { 504 /* With relatively few events, it's faster to 505 * iterate over the event IDR 506 */ 507 idr_for_each_entry(&p->event_idr, ev, id) { 508 if (id >= KFD_SIGNAL_EVENT_LIMIT) 509 break; 510 511 if (slots[id] != UNSIGNALED_EVENT_SLOT) 512 set_event_from_interrupt(p, ev); 513 } 514 } else { 515 /* With relatively many events, it's faster to 516 * iterate over the signal slots and lookup 517 * only signaled events from the IDR. 518 */ 519 for (id = 0; id < KFD_SIGNAL_EVENT_LIMIT; id++) 520 if (slots[id] != UNSIGNALED_EVENT_SLOT) { 521 ev = lookup_event_by_id(p, id); 522 set_event_from_interrupt(p, ev); 523 } 524 } 525 } 526 527 mutex_unlock(&p->event_mutex); 528 kfd_unref_process(p); 529 } 530 531 static struct kfd_event_waiter *alloc_event_waiters(uint32_t num_events) 532 { 533 struct kfd_event_waiter *event_waiters; 534 uint32_t i; 535 536 event_waiters = kmalloc_array(num_events, 537 sizeof(struct kfd_event_waiter), 538 GFP_KERNEL); 539 540 for (i = 0; (event_waiters) && (i < num_events) ; i++) { 541 init_wait(&event_waiters[i].wait); 542 event_waiters[i].activated = false; 543 } 544 545 return event_waiters; 546 } 547 548 static int init_event_waiter_get_status(struct kfd_process *p, 549 struct kfd_event_waiter *waiter, 550 uint32_t event_id) 551 { 552 struct kfd_event *ev = lookup_event_by_id(p, event_id); 553 554 if (!ev) 555 return -EINVAL; 556 557 waiter->event = ev; 558 waiter->activated = ev->signaled; 559 ev->signaled = ev->signaled && !ev->auto_reset; 560 561 return 0; 562 } 563 564 static void init_event_waiter_add_to_waitlist(struct kfd_event_waiter *waiter) 565 { 566 struct kfd_event *ev = waiter->event; 567 568 /* Only add to the wait list if we actually need to 569 * wait on this event. 570 */ 571 if (!waiter->activated) 572 add_wait_queue(&ev->wq, &waiter->wait); 573 } 574 575 /* test_event_condition - Test condition of events being waited for 576 * @all: Return completion only if all events have signaled 577 * @num_events: Number of events to wait for 578 * @event_waiters: Array of event waiters, one per event 579 * 580 * Returns KFD_IOC_WAIT_RESULT_COMPLETE if all (or one) event(s) have 581 * signaled. Returns KFD_IOC_WAIT_RESULT_TIMEOUT if no (or not all) 582 * events have signaled. Returns KFD_IOC_WAIT_RESULT_FAIL if any of 583 * the events have been destroyed. 584 */ 585 static uint32_t test_event_condition(bool all, uint32_t num_events, 586 struct kfd_event_waiter *event_waiters) 587 { 588 uint32_t i; 589 uint32_t activated_count = 0; 590 591 for (i = 0; i < num_events; i++) { 592 if (!event_waiters[i].event) 593 return KFD_IOC_WAIT_RESULT_FAIL; 594 595 if (event_waiters[i].activated) { 596 if (!all) 597 return KFD_IOC_WAIT_RESULT_COMPLETE; 598 599 activated_count++; 600 } 601 } 602 603 return activated_count == num_events ? 604 KFD_IOC_WAIT_RESULT_COMPLETE : KFD_IOC_WAIT_RESULT_TIMEOUT; 605 } 606 607 /* 608 * Copy event specific data, if defined. 609 * Currently only memory exception events have additional data to copy to user 610 */ 611 static int copy_signaled_event_data(uint32_t num_events, 612 struct kfd_event_waiter *event_waiters, 613 struct kfd_event_data __user *data) 614 { 615 struct kfd_hsa_memory_exception_data *src; 616 struct kfd_hsa_memory_exception_data __user *dst; 617 struct kfd_event_waiter *waiter; 618 struct kfd_event *event; 619 uint32_t i; 620 621 for (i = 0; i < num_events; i++) { 622 waiter = &event_waiters[i]; 623 event = waiter->event; 624 if (waiter->activated && event->type == KFD_EVENT_TYPE_MEMORY) { 625 dst = &data[i].memory_exception_data; 626 src = &event->memory_exception_data; 627 if (copy_to_user(dst, src, 628 sizeof(struct kfd_hsa_memory_exception_data))) 629 return -EFAULT; 630 } 631 } 632 633 return 0; 634 635 } 636 637 638 639 static long user_timeout_to_jiffies(uint32_t user_timeout_ms) 640 { 641 if (user_timeout_ms == KFD_EVENT_TIMEOUT_IMMEDIATE) 642 return 0; 643 644 if (user_timeout_ms == KFD_EVENT_TIMEOUT_INFINITE) 645 return MAX_SCHEDULE_TIMEOUT; 646 647 /* 648 * msecs_to_jiffies interprets all values above 2^31-1 as infinite, 649 * but we consider them finite. 650 * This hack is wrong, but nobody is likely to notice. 651 */ 652 user_timeout_ms = min_t(uint32_t, user_timeout_ms, 0x7FFFFFFF); 653 654 return msecs_to_jiffies(user_timeout_ms) + 1; 655 } 656 657 static void free_waiters(uint32_t num_events, struct kfd_event_waiter *waiters) 658 { 659 uint32_t i; 660 661 for (i = 0; i < num_events; i++) 662 if (waiters[i].event) 663 remove_wait_queue(&waiters[i].event->wq, 664 &waiters[i].wait); 665 666 kfree(waiters); 667 } 668 669 int kfd_wait_on_events(struct kfd_process *p, 670 uint32_t num_events, void __user *data, 671 bool all, uint32_t user_timeout_ms, 672 uint32_t *wait_result) 673 { 674 struct kfd_event_data __user *events = 675 (struct kfd_event_data __user *) data; 676 uint32_t i; 677 int ret = 0; 678 679 struct kfd_event_waiter *event_waiters = NULL; 680 long timeout = user_timeout_to_jiffies(user_timeout_ms); 681 682 event_waiters = alloc_event_waiters(num_events); 683 if (!event_waiters) { 684 ret = -ENOMEM; 685 goto out; 686 } 687 688 mutex_lock(&p->event_mutex); 689 690 for (i = 0; i < num_events; i++) { 691 struct kfd_event_data event_data; 692 693 if (copy_from_user(&event_data, &events[i], 694 sizeof(struct kfd_event_data))) { 695 ret = -EFAULT; 696 goto out_unlock; 697 } 698 699 ret = init_event_waiter_get_status(p, &event_waiters[i], 700 event_data.event_id); 701 if (ret) 702 goto out_unlock; 703 } 704 705 /* Check condition once. */ 706 *wait_result = test_event_condition(all, num_events, event_waiters); 707 if (*wait_result == KFD_IOC_WAIT_RESULT_COMPLETE) { 708 ret = copy_signaled_event_data(num_events, 709 event_waiters, events); 710 goto out_unlock; 711 } else if (WARN_ON(*wait_result == KFD_IOC_WAIT_RESULT_FAIL)) { 712 /* This should not happen. Events shouldn't be 713 * destroyed while we're holding the event_mutex 714 */ 715 goto out_unlock; 716 } 717 718 /* Add to wait lists if we need to wait. */ 719 for (i = 0; i < num_events; i++) 720 init_event_waiter_add_to_waitlist(&event_waiters[i]); 721 722 mutex_unlock(&p->event_mutex); 723 724 while (true) { 725 if (fatal_signal_pending(current)) { 726 ret = -EINTR; 727 break; 728 } 729 730 if (signal_pending(current)) { 731 /* 732 * This is wrong when a nonzero, non-infinite timeout 733 * is specified. We need to use 734 * ERESTARTSYS_RESTARTBLOCK, but struct restart_block 735 * contains a union with data for each user and it's 736 * in generic kernel code that I don't want to 737 * touch yet. 738 */ 739 ret = -ERESTARTSYS; 740 break; 741 } 742 743 /* Set task state to interruptible sleep before 744 * checking wake-up conditions. A concurrent wake-up 745 * will put the task back into runnable state. In that 746 * case schedule_timeout will not put the task to 747 * sleep and we'll get a chance to re-check the 748 * updated conditions almost immediately. Otherwise, 749 * this race condition would lead to a soft hang or a 750 * very long sleep. 751 */ 752 set_current_state(TASK_INTERRUPTIBLE); 753 754 *wait_result = test_event_condition(all, num_events, 755 event_waiters); 756 if (*wait_result != KFD_IOC_WAIT_RESULT_TIMEOUT) 757 break; 758 759 if (timeout <= 0) 760 break; 761 762 timeout = schedule_timeout(timeout); 763 } 764 __set_current_state(TASK_RUNNING); 765 766 /* copy_signaled_event_data may sleep. So this has to happen 767 * after the task state is set back to RUNNING. 768 */ 769 if (!ret && *wait_result == KFD_IOC_WAIT_RESULT_COMPLETE) 770 ret = copy_signaled_event_data(num_events, 771 event_waiters, events); 772 773 mutex_lock(&p->event_mutex); 774 out_unlock: 775 free_waiters(num_events, event_waiters); 776 mutex_unlock(&p->event_mutex); 777 out: 778 if (ret) 779 *wait_result = KFD_IOC_WAIT_RESULT_FAIL; 780 else if (*wait_result == KFD_IOC_WAIT_RESULT_FAIL) 781 ret = -EIO; 782 783 return ret; 784 } 785 786 int kfd_event_mmap(struct kfd_process *p, struct vm_area_struct *vma) 787 { 788 unsigned long pfn; 789 struct kfd_signal_page *page; 790 int ret; 791 792 /* check required size doesn't exceed the allocated size */ 793 if (get_order(KFD_SIGNAL_EVENT_LIMIT * 8) < 794 get_order(vma->vm_end - vma->vm_start)) { 795 pr_err("Event page mmap requested illegal size\n"); 796 return -EINVAL; 797 } 798 799 page = p->signal_page; 800 if (!page) { 801 /* Probably KFD bug, but mmap is user-accessible. */ 802 pr_debug("Signal page could not be found\n"); 803 return -EINVAL; 804 } 805 806 pfn = __pa(page->kernel_address); 807 pfn >>= PAGE_SHIFT; 808 809 vma->vm_flags |= VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_NORESERVE 810 | VM_DONTDUMP | VM_PFNMAP; 811 812 pr_debug("Mapping signal page\n"); 813 pr_debug(" start user address == 0x%08lx\n", vma->vm_start); 814 pr_debug(" end user address == 0x%08lx\n", vma->vm_end); 815 pr_debug(" pfn == 0x%016lX\n", pfn); 816 pr_debug(" vm_flags == 0x%08lX\n", vma->vm_flags); 817 pr_debug(" size == 0x%08lX\n", 818 vma->vm_end - vma->vm_start); 819 820 page->user_address = (uint64_t __user *)vma->vm_start; 821 822 /* mapping the page to user process */ 823 ret = remap_pfn_range(vma, vma->vm_start, pfn, 824 vma->vm_end - vma->vm_start, vma->vm_page_prot); 825 if (!ret) 826 p->signal_mapped_size = vma->vm_end - vma->vm_start; 827 828 return ret; 829 } 830 831 /* 832 * Assumes that p->event_mutex is held and of course 833 * that p is not going away (current or locked). 834 */ 835 static void lookup_events_by_type_and_signal(struct kfd_process *p, 836 int type, void *event_data) 837 { 838 struct kfd_hsa_memory_exception_data *ev_data; 839 struct kfd_event *ev; 840 uint32_t id; 841 bool send_signal = true; 842 843 ev_data = (struct kfd_hsa_memory_exception_data *) event_data; 844 845 id = KFD_FIRST_NONSIGNAL_EVENT_ID; 846 idr_for_each_entry_continue(&p->event_idr, ev, id) 847 if (ev->type == type) { 848 send_signal = false; 849 dev_dbg(kfd_device, 850 "Event found: id %X type %d", 851 ev->event_id, ev->type); 852 set_event(ev); 853 if (ev->type == KFD_EVENT_TYPE_MEMORY && ev_data) 854 ev->memory_exception_data = *ev_data; 855 } 856 857 if (type == KFD_EVENT_TYPE_MEMORY) { 858 dev_warn(kfd_device, 859 "Sending SIGSEGV to process %d (pasid 0x%x)", 860 p->lead_thread->pid, p->pasid); 861 send_sig(SIGSEGV, p->lead_thread, 0); 862 } 863 864 /* Send SIGTERM no event of type "type" has been found*/ 865 if (send_signal) { 866 if (send_sigterm) { 867 dev_warn(kfd_device, 868 "Sending SIGTERM to process %d (pasid 0x%x)", 869 p->lead_thread->pid, p->pasid); 870 send_sig(SIGTERM, p->lead_thread, 0); 871 } else { 872 dev_err(kfd_device, 873 "Process %d (pasid 0x%x) got unhandled exception", 874 p->lead_thread->pid, p->pasid); 875 } 876 } 877 } 878 879 #ifdef KFD_SUPPORT_IOMMU_V2 880 void kfd_signal_iommu_event(struct kfd_dev *dev, unsigned int pasid, 881 unsigned long address, bool is_write_requested, 882 bool is_execute_requested) 883 { 884 struct kfd_hsa_memory_exception_data memory_exception_data; 885 struct vm_area_struct *vma; 886 887 /* 888 * Because we are called from arbitrary context (workqueue) as opposed 889 * to process context, kfd_process could attempt to exit while we are 890 * running so the lookup function increments the process ref count. 891 */ 892 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid); 893 struct mm_struct *mm; 894 895 if (!p) 896 return; /* Presumably process exited. */ 897 898 /* Take a safe reference to the mm_struct, which may otherwise 899 * disappear even while the kfd_process is still referenced. 900 */ 901 mm = get_task_mm(p->lead_thread); 902 if (!mm) { 903 kfd_unref_process(p); 904 return; /* Process is exiting */ 905 } 906 907 memset(&memory_exception_data, 0, sizeof(memory_exception_data)); 908 909 down_read(&mm->mmap_sem); 910 vma = find_vma(mm, address); 911 912 memory_exception_data.gpu_id = dev->id; 913 memory_exception_data.va = address; 914 /* Set failure reason */ 915 memory_exception_data.failure.NotPresent = 1; 916 memory_exception_data.failure.NoExecute = 0; 917 memory_exception_data.failure.ReadOnly = 0; 918 if (vma && address >= vma->vm_start) { 919 memory_exception_data.failure.NotPresent = 0; 920 921 if (is_write_requested && !(vma->vm_flags & VM_WRITE)) 922 memory_exception_data.failure.ReadOnly = 1; 923 else 924 memory_exception_data.failure.ReadOnly = 0; 925 926 if (is_execute_requested && !(vma->vm_flags & VM_EXEC)) 927 memory_exception_data.failure.NoExecute = 1; 928 else 929 memory_exception_data.failure.NoExecute = 0; 930 } 931 932 up_read(&mm->mmap_sem); 933 mmput(mm); 934 935 pr_debug("notpresent %d, noexecute %d, readonly %d\n", 936 memory_exception_data.failure.NotPresent, 937 memory_exception_data.failure.NoExecute, 938 memory_exception_data.failure.ReadOnly); 939 940 /* Workaround on Raven to not kill the process when memory is freed 941 * before IOMMU is able to finish processing all the excessive PPRs 942 */ 943 if (dev->device_info->asic_family != CHIP_RAVEN && 944 dev->device_info->asic_family != CHIP_RENOIR) { 945 mutex_lock(&p->event_mutex); 946 947 /* Lookup events by type and signal them */ 948 lookup_events_by_type_and_signal(p, KFD_EVENT_TYPE_MEMORY, 949 &memory_exception_data); 950 951 mutex_unlock(&p->event_mutex); 952 } 953 954 kfd_unref_process(p); 955 } 956 #endif /* KFD_SUPPORT_IOMMU_V2 */ 957 958 void kfd_signal_hw_exception_event(unsigned int pasid) 959 { 960 /* 961 * Because we are called from arbitrary context (workqueue) as opposed 962 * to process context, kfd_process could attempt to exit while we are 963 * running so the lookup function increments the process ref count. 964 */ 965 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid); 966 967 if (!p) 968 return; /* Presumably process exited. */ 969 970 mutex_lock(&p->event_mutex); 971 972 /* Lookup events by type and signal them */ 973 lookup_events_by_type_and_signal(p, KFD_EVENT_TYPE_HW_EXCEPTION, NULL); 974 975 mutex_unlock(&p->event_mutex); 976 kfd_unref_process(p); 977 } 978 979 void kfd_signal_vm_fault_event(struct kfd_dev *dev, unsigned int pasid, 980 struct kfd_vm_fault_info *info) 981 { 982 struct kfd_event *ev; 983 uint32_t id; 984 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid); 985 struct kfd_hsa_memory_exception_data memory_exception_data; 986 987 if (!p) 988 return; /* Presumably process exited. */ 989 memset(&memory_exception_data, 0, sizeof(memory_exception_data)); 990 memory_exception_data.gpu_id = dev->id; 991 memory_exception_data.failure.imprecise = true; 992 /* Set failure reason */ 993 if (info) { 994 memory_exception_data.va = (info->page_addr) << PAGE_SHIFT; 995 memory_exception_data.failure.NotPresent = 996 info->prot_valid ? 1 : 0; 997 memory_exception_data.failure.NoExecute = 998 info->prot_exec ? 1 : 0; 999 memory_exception_data.failure.ReadOnly = 1000 info->prot_write ? 1 : 0; 1001 memory_exception_data.failure.imprecise = 0; 1002 } 1003 mutex_lock(&p->event_mutex); 1004 1005 id = KFD_FIRST_NONSIGNAL_EVENT_ID; 1006 idr_for_each_entry_continue(&p->event_idr, ev, id) 1007 if (ev->type == KFD_EVENT_TYPE_MEMORY) { 1008 ev->memory_exception_data = memory_exception_data; 1009 set_event(ev); 1010 } 1011 1012 mutex_unlock(&p->event_mutex); 1013 kfd_unref_process(p); 1014 } 1015 1016 void kfd_signal_reset_event(struct kfd_dev *dev) 1017 { 1018 struct kfd_hsa_hw_exception_data hw_exception_data; 1019 struct kfd_hsa_memory_exception_data memory_exception_data; 1020 struct kfd_process *p; 1021 struct kfd_event *ev; 1022 unsigned int temp; 1023 uint32_t id, idx; 1024 int reset_cause = atomic_read(&dev->sram_ecc_flag) ? 1025 KFD_HW_EXCEPTION_ECC : 1026 KFD_HW_EXCEPTION_GPU_HANG; 1027 1028 /* Whole gpu reset caused by GPU hang and memory is lost */ 1029 memset(&hw_exception_data, 0, sizeof(hw_exception_data)); 1030 hw_exception_data.gpu_id = dev->id; 1031 hw_exception_data.memory_lost = 1; 1032 hw_exception_data.reset_cause = reset_cause; 1033 1034 memset(&memory_exception_data, 0, sizeof(memory_exception_data)); 1035 memory_exception_data.ErrorType = KFD_MEM_ERR_SRAM_ECC; 1036 memory_exception_data.gpu_id = dev->id; 1037 memory_exception_data.failure.imprecise = true; 1038 1039 idx = srcu_read_lock(&kfd_processes_srcu); 1040 hash_for_each_rcu(kfd_processes_table, temp, p, kfd_processes) { 1041 mutex_lock(&p->event_mutex); 1042 id = KFD_FIRST_NONSIGNAL_EVENT_ID; 1043 idr_for_each_entry_continue(&p->event_idr, ev, id) { 1044 if (ev->type == KFD_EVENT_TYPE_HW_EXCEPTION) { 1045 ev->hw_exception_data = hw_exception_data; 1046 set_event(ev); 1047 } 1048 if (ev->type == KFD_EVENT_TYPE_MEMORY && 1049 reset_cause == KFD_HW_EXCEPTION_ECC) { 1050 ev->memory_exception_data = memory_exception_data; 1051 set_event(ev); 1052 } 1053 } 1054 mutex_unlock(&p->event_mutex); 1055 } 1056 srcu_read_unlock(&kfd_processes_srcu, idx); 1057 } 1058
Indexes created Sun Sep 21 18:09:52 GMT 2025