1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Copyright 2014-2022 Advanced Micro Devices, Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 */
23
24#include <linux/mm_types.h>
25#include <linux/slab.h>
26#include <linux/types.h>
27#include <linux/sched/signal.h>
28#include <linux/sched/mm.h>
29#include <linux/uaccess.h>
30#include <linux/mman.h>
31#include <linux/memory.h>
32#include "kfd_priv.h"
33#include "kfd_events.h"
34#include <linux/device.h>
35
36/*
37 * Wrapper around wait_queue_entry_t
38 */
39struct kfd_event_waiter {
40 wait_queue_entry_t wait;
41 struct kfd_event *event; /* Event to wait for */
42 bool activated; /* Becomes true when event is signaled */
43 bool event_age_enabled; /* set to true when last_event_age is non-zero */
44};
45
46/*
47 * Each signal event needs a 64-bit signal slot where the signaler will write
48 * a 1 before sending an interrupt. (This is needed because some interrupts
49 * do not contain enough spare data bits to identify an event.)
50 * We get whole pages and map them to the process VA.
51 * Individual signal events use their event_id as slot index.
52 */
53struct kfd_signal_page {
54 uint64_t *kernel_address;
55 uint64_t __user *user_address;
56 bool need_to_free_pages;
57};
58
59static uint64_t *page_slots(struct kfd_signal_page *page)
60{
61 return page->kernel_address;
62}
63
64static struct kfd_signal_page *allocate_signal_page(struct kfd_process *p)
65{
66 void *backing_store;
67 struct kfd_signal_page *page;
68
69 page = kzalloc(size: sizeof(*page), GFP_KERNEL);
70 if (!page)
71 return NULL;
72
73 backing_store = (void *) __get_free_pages(GFP_KERNEL,
74 order: get_order(KFD_SIGNAL_EVENT_LIMIT * 8));
75 if (!backing_store)
76 goto fail_alloc_signal_store;
77
78 /* Initialize all events to unsignaled */
79 memset(backing_store, (uint8_t) UNSIGNALED_EVENT_SLOT,
80 KFD_SIGNAL_EVENT_LIMIT * 8);
81
82 page->kernel_address = backing_store;
83 page->need_to_free_pages = true;
84 pr_debug("Allocated new event signal page at %p, for process %p\n",
85 page, p);
86
87 return page;
88
89fail_alloc_signal_store:
90 kfree(objp: page);
91 return NULL;
92}
93
94static int allocate_event_notification_slot(struct kfd_process *p,
95 struct kfd_event *ev,
96 const int *restore_id)
97{
98 int id;
99
100 if (!p->signal_page) {
101 p->signal_page = allocate_signal_page(p);
102 if (!p->signal_page)
103 return -ENOMEM;
104 /* Oldest user mode expects 256 event slots */
105 p->signal_mapped_size = 256*8;
106 }
107
108 if (restore_id) {
109 id = idr_alloc(&p->event_idr, ptr: ev, start: *restore_id, end: *restore_id + 1,
110 GFP_KERNEL);
111 } else {
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, ptr: ev, start: 0, end: p->signal_mapped_size / 8,
119 GFP_KERNEL);
120 }
121 if (id < 0)
122 return id;
123
124 ev->event_id = id;
125 page_slots(page: p->signal_page)[id] = UNSIGNALED_EVENT_SLOT;
126
127 return 0;
128}
129
130/*
131 * Assumes that p->event_mutex or rcu_readlock is held and of course that p is
132 * not going away.
133 */
134static struct kfd_event *lookup_event_by_id(struct kfd_process *p, uint32_t id)
135{
136 return idr_find(&p->event_idr, id);
137}
138
139/**
140 * lookup_signaled_event_by_partial_id - Lookup signaled event from partial ID
141 * @p: Pointer to struct kfd_process
142 * @id: ID to look up
143 * @bits: Number of valid bits in @id
144 *
145 * Finds the first signaled event with a matching partial ID. If no
146 * matching signaled event is found, returns NULL. In that case the
147 * caller should assume that the partial ID is invalid and do an
148 * exhaustive search of all siglaned events.
149 *
150 * If multiple events with the same partial ID signal at the same
151 * time, they will be found one interrupt at a time, not necessarily
152 * in the same order the interrupts occurred. As long as the number of
153 * interrupts is correct, all signaled events will be seen by the
154 * driver.
155 */
156static struct kfd_event *lookup_signaled_event_by_partial_id(
157 struct kfd_process *p, uint32_t id, uint32_t bits)
158{
159 struct kfd_event *ev;
160
161 if (!p->signal_page || id >= KFD_SIGNAL_EVENT_LIMIT)
162 return NULL;
163
164 /* Fast path for the common case that @id is not a partial ID
165 * and we only need a single lookup.
166 */
167 if (bits > 31 || (1U << bits) >= KFD_SIGNAL_EVENT_LIMIT) {
168 if (page_slots(page: p->signal_page)[id] == UNSIGNALED_EVENT_SLOT)
169 return NULL;
170
171 return idr_find(&p->event_idr, id);
172 }
173
174 /* General case for partial IDs: Iterate over all matching IDs
175 * and find the first one that has signaled.
176 */
177 for (ev = NULL; id < KFD_SIGNAL_EVENT_LIMIT && !ev; id += 1U << bits) {
178 if (page_slots(page: p->signal_page)[id] == UNSIGNALED_EVENT_SLOT)
179 continue;
180
181 ev = idr_find(&p->event_idr, id);
182 }
183
184 return ev;
185}
186
187static int create_signal_event(struct file *devkfd, struct kfd_process *p,
188 struct kfd_event *ev, const int *restore_id)
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_debug("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, restore_id);
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
217static int create_other_event(struct kfd_process *p, struct kfd_event *ev, const int *restore_id)
218{
219 int id;
220
221 if (restore_id)
222 id = idr_alloc(&p->event_idr, ptr: ev, start: *restore_id, end: *restore_id + 1,
223 GFP_KERNEL);
224 else
225 /* Cast KFD_LAST_NONSIGNAL_EVENT to uint32_t. This allows an
226 * intentional integer overflow to -1 without a compiler
227 * warning. idr_alloc treats a negative value as "maximum
228 * signed integer".
229 */
230 id = idr_alloc(&p->event_idr, ptr: ev, KFD_FIRST_NONSIGNAL_EVENT_ID,
231 end: (uint32_t)KFD_LAST_NONSIGNAL_EVENT_ID + 1,
232 GFP_KERNEL);
233
234 if (id < 0)
235 return id;
236 ev->event_id = id;
237
238 return 0;
239}
240
241int kfd_event_init_process(struct kfd_process *p)
242{
243 int id;
244
245 mutex_init(&p->event_mutex);
246 idr_init(idr: &p->event_idr);
247 p->signal_page = NULL;
248 p->signal_event_count = 1;
249 /* Allocate event ID 0. It is used for a fast path to ignore bogus events
250 * that are sent by the CP without a context ID
251 */
252 id = idr_alloc(&p->event_idr, NULL, start: 0, end: 1, GFP_KERNEL);
253 if (id < 0) {
254 idr_destroy(&p->event_idr);
255 mutex_destroy(lock: &p->event_mutex);
256 return id;
257 }
258 return 0;
259}
260
261static void destroy_event(struct kfd_process *p, struct kfd_event *ev)
262{
263 struct kfd_event_waiter *waiter;
264
265 /* Wake up pending waiters. They will return failure */
266 spin_lock(lock: &ev->lock);
267 list_for_each_entry(waiter, &ev->wq.head, wait.entry)
268 WRITE_ONCE(waiter->event, NULL);
269 wake_up_all(&ev->wq);
270 spin_unlock(lock: &ev->lock);
271
272 if (ev->type == KFD_EVENT_TYPE_SIGNAL ||
273 ev->type == KFD_EVENT_TYPE_DEBUG)
274 p->signal_event_count--;
275
276 idr_remove(&p->event_idr, id: ev->event_id);
277 kfree_rcu(ev, rcu);
278}
279
280static void destroy_events(struct kfd_process *p)
281{
282 struct kfd_event *ev;
283 uint32_t id;
284
285 idr_for_each_entry(&p->event_idr, ev, id)
286 if (ev)
287 destroy_event(p, ev);
288 idr_destroy(&p->event_idr);
289 mutex_destroy(lock: &p->event_mutex);
290}
291
292/*
293 * We assume that the process is being destroyed and there is no need to
294 * unmap the pages or keep bookkeeping data in order.
295 */
296static void shutdown_signal_page(struct kfd_process *p)
297{
298 struct kfd_signal_page *page = p->signal_page;
299
300 if (page) {
301 if (page->need_to_free_pages)
302 free_pages(addr: (unsigned long)page->kernel_address,
303 order: get_order(KFD_SIGNAL_EVENT_LIMIT * 8));
304 kfree(objp: page);
305 }
306}
307
308void kfd_event_free_process(struct kfd_process *p)
309{
310 destroy_events(p);
311 shutdown_signal_page(p);
312}
313
314static bool event_can_be_gpu_signaled(const struct kfd_event *ev)
315{
316 return ev->type == KFD_EVENT_TYPE_SIGNAL ||
317 ev->type == KFD_EVENT_TYPE_DEBUG;
318}
319
320static bool event_can_be_cpu_signaled(const struct kfd_event *ev)
321{
322 return ev->type == KFD_EVENT_TYPE_SIGNAL;
323}
324
325static int kfd_event_page_set(struct kfd_process *p, void *kernel_address,
326 uint64_t size, uint64_t user_handle)
327{
328 struct kfd_signal_page *page;
329
330 if (p->signal_page)
331 return -EBUSY;
332
333 page = kzalloc(size: sizeof(*page), GFP_KERNEL);
334 if (!page)
335 return -ENOMEM;
336
337 /* Initialize all events to unsignaled */
338 memset(kernel_address, (uint8_t) UNSIGNALED_EVENT_SLOT,
339 KFD_SIGNAL_EVENT_LIMIT * 8);
340
341 page->kernel_address = kernel_address;
342
343 p->signal_page = page;
344 p->signal_mapped_size = size;
345 p->signal_handle = user_handle;
346 return 0;
347}
348
349int kfd_kmap_event_page(struct kfd_process *p, uint64_t event_page_offset)
350{
351 struct kfd_node *kfd;
352 struct kfd_process_device *pdd;
353 void *mem, *kern_addr;
354 uint64_t size;
355 int err = 0;
356
357 if (p->signal_page) {
358 pr_err("Event page is already set\n");
359 return -EINVAL;
360 }
361
362 pdd = kfd_process_device_data_by_id(process: p, GET_GPU_ID(event_page_offset));
363 if (!pdd) {
364 pr_err("Getting device by id failed in %s\n", __func__);
365 return -EINVAL;
366 }
367 kfd = pdd->dev;
368
369 pdd = kfd_bind_process_to_device(dev: kfd, p);
370 if (IS_ERR(ptr: pdd))
371 return PTR_ERR(ptr: pdd);
372
373 mem = kfd_process_device_translate_handle(p: pdd,
374 GET_IDR_HANDLE(event_page_offset));
375 if (!mem) {
376 pr_err("Can't find BO, offset is 0x%llx\n", event_page_offset);
377 return -EINVAL;
378 }
379
380 err = amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel(mem, kptr: &kern_addr, size: &size);
381 if (err) {
382 pr_err("Failed to map event page to kernel\n");
383 return err;
384 }
385
386 err = kfd_event_page_set(p, kernel_address: kern_addr, size, user_handle: event_page_offset);
387 if (err) {
388 pr_err("Failed to set event page\n");
389 amdgpu_amdkfd_gpuvm_unmap_gtt_bo_from_kernel(mem);
390 return err;
391 }
392 return err;
393}
394
395int kfd_event_create(struct file *devkfd, struct kfd_process *p,
396 uint32_t event_type, bool auto_reset, uint32_t node_id,
397 uint32_t *event_id, uint32_t *event_trigger_data,
398 uint64_t *event_page_offset, uint32_t *event_slot_index)
399{
400 int ret = 0;
401 struct kfd_event *ev = kzalloc(size: sizeof(*ev), GFP_KERNEL);
402
403 if (!ev)
404 return -ENOMEM;
405
406 ev->type = event_type;
407 ev->auto_reset = auto_reset;
408 ev->signaled = false;
409
410 spin_lock_init(&ev->lock);
411 init_waitqueue_head(&ev->wq);
412
413 *event_page_offset = 0;
414
415 mutex_lock(&p->event_mutex);
416
417 switch (event_type) {
418 case KFD_EVENT_TYPE_SIGNAL:
419 case KFD_EVENT_TYPE_DEBUG:
420 ret = create_signal_event(devkfd, p, ev, NULL);
421 if (!ret) {
422 *event_page_offset = KFD_MMAP_TYPE_EVENTS;
423 *event_slot_index = ev->event_id;
424 }
425 break;
426 default:
427 ret = create_other_event(p, ev, NULL);
428 break;
429 }
430
431 if (!ret) {
432 *event_id = ev->event_id;
433 *event_trigger_data = ev->event_id;
434 ev->event_age = 1;
435 } else {
436 kfree(objp: ev);
437 }
438
439 mutex_unlock(lock: &p->event_mutex);
440
441 return ret;
442}
443
444int kfd_criu_restore_event(struct file *devkfd,
445 struct kfd_process *p,
446 uint8_t __user *user_priv_ptr,
447 uint64_t *priv_data_offset,
448 uint64_t max_priv_data_size)
449{
450 struct kfd_criu_event_priv_data *ev_priv;
451 struct kfd_event *ev = NULL;
452 int ret = 0;
453
454 ev_priv = kmalloc(size: sizeof(*ev_priv), GFP_KERNEL);
455 if (!ev_priv)
456 return -ENOMEM;
457
458 ev = kzalloc(size: sizeof(*ev), GFP_KERNEL);
459 if (!ev) {
460 ret = -ENOMEM;
461 goto exit;
462 }
463
464 if (*priv_data_offset + sizeof(*ev_priv) > max_priv_data_size) {
465 ret = -EINVAL;
466 goto exit;
467 }
468
469 ret = copy_from_user(to: ev_priv, from: user_priv_ptr + *priv_data_offset, n: sizeof(*ev_priv));
470 if (ret) {
471 ret = -EFAULT;
472 goto exit;
473 }
474 *priv_data_offset += sizeof(*ev_priv);
475
476 if (ev_priv->user_handle) {
477 ret = kfd_kmap_event_page(p, event_page_offset: ev_priv->user_handle);
478 if (ret)
479 goto exit;
480 }
481
482 ev->type = ev_priv->type;
483 ev->auto_reset = ev_priv->auto_reset;
484 ev->signaled = ev_priv->signaled;
485
486 spin_lock_init(&ev->lock);
487 init_waitqueue_head(&ev->wq);
488
489 mutex_lock(&p->event_mutex);
490 switch (ev->type) {
491 case KFD_EVENT_TYPE_SIGNAL:
492 case KFD_EVENT_TYPE_DEBUG:
493 ret = create_signal_event(devkfd, p, ev, restore_id: &ev_priv->event_id);
494 break;
495 case KFD_EVENT_TYPE_MEMORY:
496 memcpy(&ev->memory_exception_data,
497 &ev_priv->memory_exception_data,
498 sizeof(struct kfd_hsa_memory_exception_data));
499
500 ret = create_other_event(p, ev, restore_id: &ev_priv->event_id);
501 break;
502 case KFD_EVENT_TYPE_HW_EXCEPTION:
503 memcpy(&ev->hw_exception_data,
504 &ev_priv->hw_exception_data,
505 sizeof(struct kfd_hsa_hw_exception_data));
506
507 ret = create_other_event(p, ev, restore_id: &ev_priv->event_id);
508 break;
509 }
510 mutex_unlock(lock: &p->event_mutex);
511
512exit:
513 if (ret)
514 kfree(objp: ev);
515
516 kfree(objp: ev_priv);
517
518 return ret;
519}
520
521int kfd_criu_checkpoint_events(struct kfd_process *p,
522 uint8_t __user *user_priv_data,
523 uint64_t *priv_data_offset)
524{
525 struct kfd_criu_event_priv_data *ev_privs;
526 int i = 0;
527 int ret = 0;
528 struct kfd_event *ev;
529 uint32_t ev_id;
530
531 uint32_t num_events = kfd_get_num_events(p);
532
533 if (!num_events)
534 return 0;
535
536 ev_privs = kvzalloc(size: num_events * sizeof(*ev_privs), GFP_KERNEL);
537 if (!ev_privs)
538 return -ENOMEM;
539
540
541 idr_for_each_entry(&p->event_idr, ev, ev_id) {
542 struct kfd_criu_event_priv_data *ev_priv;
543
544 /*
545 * Currently, all events have same size of private_data, but the current ioctl's
546 * and CRIU plugin supports private_data of variable sizes
547 */
548 ev_priv = &ev_privs[i];
549
550 ev_priv->object_type = KFD_CRIU_OBJECT_TYPE_EVENT;
551
552 /* We store the user_handle with the first event */
553 if (i == 0 && p->signal_page)
554 ev_priv->user_handle = p->signal_handle;
555
556 ev_priv->event_id = ev->event_id;
557 ev_priv->auto_reset = ev->auto_reset;
558 ev_priv->type = ev->type;
559 ev_priv->signaled = ev->signaled;
560
561 if (ev_priv->type == KFD_EVENT_TYPE_MEMORY)
562 memcpy(&ev_priv->memory_exception_data,
563 &ev->memory_exception_data,
564 sizeof(struct kfd_hsa_memory_exception_data));
565 else if (ev_priv->type == KFD_EVENT_TYPE_HW_EXCEPTION)
566 memcpy(&ev_priv->hw_exception_data,
567 &ev->hw_exception_data,
568 sizeof(struct kfd_hsa_hw_exception_data));
569
570 pr_debug("Checkpointed event[%d] id = 0x%08x auto_reset = %x type = %x signaled = %x\n",
571 i,
572 ev_priv->event_id,
573 ev_priv->auto_reset,
574 ev_priv->type,
575 ev_priv->signaled);
576 i++;
577 }
578
579 ret = copy_to_user(to: user_priv_data + *priv_data_offset,
580 from: ev_privs, n: num_events * sizeof(*ev_privs));
581 if (ret) {
582 pr_err("Failed to copy events priv to user\n");
583 ret = -EFAULT;
584 }
585
586 *priv_data_offset += num_events * sizeof(*ev_privs);
587
588 kvfree(addr: ev_privs);
589 return ret;
590}
591
592int kfd_get_num_events(struct kfd_process *p)
593{
594 struct kfd_event *ev;
595 uint32_t id;
596 u32 num_events = 0;
597
598 idr_for_each_entry(&p->event_idr, ev, id)
599 num_events++;
600
601 return num_events;
602}
603
604/* Assumes that p is current. */
605int kfd_event_destroy(struct kfd_process *p, uint32_t event_id)
606{
607 struct kfd_event *ev;
608 int ret = 0;
609
610 mutex_lock(&p->event_mutex);
611
612 ev = lookup_event_by_id(p, id: event_id);
613
614 if (ev)
615 destroy_event(p, ev);
616 else
617 ret = -EINVAL;
618
619 mutex_unlock(lock: &p->event_mutex);
620 return ret;
621}
622
623static void set_event(struct kfd_event *ev)
624{
625 struct kfd_event_waiter *waiter;
626
627 /* Auto reset if the list is non-empty and we're waking
628 * someone. waitqueue_active is safe here because we're
629 * protected by the ev->lock, which is also held when
630 * updating the wait queues in kfd_wait_on_events.
631 */
632 ev->signaled = !ev->auto_reset || !waitqueue_active(wq_head: &ev->wq);
633 if (!(++ev->event_age)) {
634 /* Never wrap back to reserved/default event age 0/1 */
635 ev->event_age = 2;
636 WARN_ONCE(1, "event_age wrap back!");
637 }
638
639 list_for_each_entry(waiter, &ev->wq.head, wait.entry)
640 WRITE_ONCE(waiter->activated, true);
641
642 wake_up_all(&ev->wq);
643}
644
645/* Assumes that p is current. */
646int kfd_set_event(struct kfd_process *p, uint32_t event_id)
647{
648 int ret = 0;
649 struct kfd_event *ev;
650
651 rcu_read_lock();
652
653 ev = lookup_event_by_id(p, id: event_id);
654 if (!ev) {
655 ret = -EINVAL;
656 goto unlock_rcu;
657 }
658 spin_lock(lock: &ev->lock);
659
660 if (event_can_be_cpu_signaled(ev))
661 set_event(ev);
662 else
663 ret = -EINVAL;
664
665 spin_unlock(lock: &ev->lock);
666unlock_rcu:
667 rcu_read_unlock();
668 return ret;
669}
670
671static void reset_event(struct kfd_event *ev)
672{
673 ev->signaled = false;
674}
675
676/* Assumes that p is current. */
677int kfd_reset_event(struct kfd_process *p, uint32_t event_id)
678{
679 int ret = 0;
680 struct kfd_event *ev;
681
682 rcu_read_lock();
683
684 ev = lookup_event_by_id(p, id: event_id);
685 if (!ev) {
686 ret = -EINVAL;
687 goto unlock_rcu;
688 }
689 spin_lock(lock: &ev->lock);
690
691 if (event_can_be_cpu_signaled(ev))
692 reset_event(ev);
693 else
694 ret = -EINVAL;
695
696 spin_unlock(lock: &ev->lock);
697unlock_rcu:
698 rcu_read_unlock();
699 return ret;
700
701}
702
703static void acknowledge_signal(struct kfd_process *p, struct kfd_event *ev)
704{
705 WRITE_ONCE(page_slots(p->signal_page)[ev->event_id], UNSIGNALED_EVENT_SLOT);
706}
707
708static void set_event_from_interrupt(struct kfd_process *p,
709 struct kfd_event *ev)
710{
711 if (ev && event_can_be_gpu_signaled(ev)) {
712 acknowledge_signal(p, ev);
713 spin_lock(lock: &ev->lock);
714 set_event(ev);
715 spin_unlock(lock: &ev->lock);
716 }
717}
718
719void kfd_signal_event_interrupt(u32 pasid, uint32_t partial_id,
720 uint32_t valid_id_bits)
721{
722 struct kfd_event *ev = NULL;
723
724 /*
725 * Because we are called from arbitrary context (workqueue) as opposed
726 * to process context, kfd_process could attempt to exit while we are
727 * running so the lookup function increments the process ref count.
728 */
729 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
730
731 if (!p)
732 return; /* Presumably process exited. */
733
734 rcu_read_lock();
735
736 if (valid_id_bits)
737 ev = lookup_signaled_event_by_partial_id(p, id: partial_id,
738 bits: valid_id_bits);
739 if (ev) {
740 set_event_from_interrupt(p, ev);
741 } else if (p->signal_page) {
742 /*
743 * Partial ID lookup failed. Assume that the event ID
744 * in the interrupt payload was invalid and do an
745 * exhaustive search of signaled events.
746 */
747 uint64_t *slots = page_slots(page: p->signal_page);
748 uint32_t id;
749
750 if (valid_id_bits)
751 pr_debug_ratelimited("Partial ID invalid: %u (%u valid bits)\n",
752 partial_id, valid_id_bits);
753
754 if (p->signal_event_count < KFD_SIGNAL_EVENT_LIMIT / 64) {
755 /* With relatively few events, it's faster to
756 * iterate over the event IDR
757 */
758 idr_for_each_entry(&p->event_idr, ev, id) {
759 if (id >= KFD_SIGNAL_EVENT_LIMIT)
760 break;
761
762 if (READ_ONCE(slots[id]) != UNSIGNALED_EVENT_SLOT)
763 set_event_from_interrupt(p, ev);
764 }
765 } else {
766 /* With relatively many events, it's faster to
767 * iterate over the signal slots and lookup
768 * only signaled events from the IDR.
769 */
770 for (id = 1; id < KFD_SIGNAL_EVENT_LIMIT; id++)
771 if (READ_ONCE(slots[id]) != UNSIGNALED_EVENT_SLOT) {
772 ev = lookup_event_by_id(p, id);
773 set_event_from_interrupt(p, ev);
774 }
775 }
776 }
777
778 rcu_read_unlock();
779 kfd_unref_process(p);
780}
781
782static struct kfd_event_waiter *alloc_event_waiters(uint32_t num_events)
783{
784 struct kfd_event_waiter *event_waiters;
785 uint32_t i;
786
787 event_waiters = kcalloc(n: num_events, size: sizeof(struct kfd_event_waiter),
788 GFP_KERNEL);
789 if (!event_waiters)
790 return NULL;
791
792 for (i = 0; i < num_events; i++)
793 init_wait(&event_waiters[i].wait);
794
795 return event_waiters;
796}
797
798static int init_event_waiter(struct kfd_process *p,
799 struct kfd_event_waiter *waiter,
800 struct kfd_event_data *event_data)
801{
802 struct kfd_event *ev = lookup_event_by_id(p, id: event_data->event_id);
803
804 if (!ev)
805 return -EINVAL;
806
807 spin_lock(lock: &ev->lock);
808 waiter->event = ev;
809 waiter->activated = ev->signaled;
810 ev->signaled = ev->signaled && !ev->auto_reset;
811
812 /* last_event_age = 0 reserved for backward compatible */
813 if (waiter->event->type == KFD_EVENT_TYPE_SIGNAL &&
814 event_data->signal_event_data.last_event_age) {
815 waiter->event_age_enabled = true;
816 if (ev->event_age != event_data->signal_event_data.last_event_age)
817 waiter->activated = true;
818 }
819
820 if (!waiter->activated)
821 add_wait_queue(wq_head: &ev->wq, wq_entry: &waiter->wait);
822 spin_unlock(lock: &ev->lock);
823
824 return 0;
825}
826
827/* test_event_condition - Test condition of events being waited for
828 * @all: Return completion only if all events have signaled
829 * @num_events: Number of events to wait for
830 * @event_waiters: Array of event waiters, one per event
831 *
832 * Returns KFD_IOC_WAIT_RESULT_COMPLETE if all (or one) event(s) have
833 * signaled. Returns KFD_IOC_WAIT_RESULT_TIMEOUT if no (or not all)
834 * events have signaled. Returns KFD_IOC_WAIT_RESULT_FAIL if any of
835 * the events have been destroyed.
836 */
837static uint32_t test_event_condition(bool all, uint32_t num_events,
838 struct kfd_event_waiter *event_waiters)
839{
840 uint32_t i;
841 uint32_t activated_count = 0;
842
843 for (i = 0; i < num_events; i++) {
844 if (!READ_ONCE(event_waiters[i].event))
845 return KFD_IOC_WAIT_RESULT_FAIL;
846
847 if (READ_ONCE(event_waiters[i].activated)) {
848 if (!all)
849 return KFD_IOC_WAIT_RESULT_COMPLETE;
850
851 activated_count++;
852 }
853 }
854
855 return activated_count == num_events ?
856 KFD_IOC_WAIT_RESULT_COMPLETE : KFD_IOC_WAIT_RESULT_TIMEOUT;
857}
858
859/*
860 * Copy event specific data, if defined.
861 * Currently only memory exception events have additional data to copy to user
862 */
863static int copy_signaled_event_data(uint32_t num_events,
864 struct kfd_event_waiter *event_waiters,
865 struct kfd_event_data __user *data)
866{
867 void *src;
868 void __user *dst;
869 struct kfd_event_waiter *waiter;
870 struct kfd_event *event;
871 uint32_t i, size = 0;
872
873 for (i = 0; i < num_events; i++) {
874 waiter = &event_waiters[i];
875 event = waiter->event;
876 if (!event)
877 return -EINVAL; /* event was destroyed */
878 if (waiter->activated) {
879 if (event->type == KFD_EVENT_TYPE_MEMORY) {
880 dst = &data[i].memory_exception_data;
881 src = &event->memory_exception_data;
882 size = sizeof(struct kfd_hsa_memory_exception_data);
883 } else if (event->type == KFD_EVENT_TYPE_SIGNAL &&
884 waiter->event_age_enabled) {
885 dst = &data[i].signal_event_data.last_event_age;
886 src = &event->event_age;
887 size = sizeof(u64);
888 }
889 if (size && copy_to_user(to: dst, from: src, n: size))
890 return -EFAULT;
891 }
892 }
893
894 return 0;
895}
896
897static long user_timeout_to_jiffies(uint32_t user_timeout_ms)
898{
899 if (user_timeout_ms == KFD_EVENT_TIMEOUT_IMMEDIATE)
900 return 0;
901
902 if (user_timeout_ms == KFD_EVENT_TIMEOUT_INFINITE)
903 return MAX_SCHEDULE_TIMEOUT;
904
905 /*
906 * msecs_to_jiffies interprets all values above 2^31-1 as infinite,
907 * but we consider them finite.
908 * This hack is wrong, but nobody is likely to notice.
909 */
910 user_timeout_ms = min_t(uint32_t, user_timeout_ms, 0x7FFFFFFF);
911
912 return msecs_to_jiffies(m: user_timeout_ms) + 1;
913}
914
915static void free_waiters(uint32_t num_events, struct kfd_event_waiter *waiters,
916 bool undo_auto_reset)
917{
918 uint32_t i;
919
920 for (i = 0; i < num_events; i++)
921 if (waiters[i].event) {
922 spin_lock(lock: &waiters[i].event->lock);
923 remove_wait_queue(wq_head: &waiters[i].event->wq,
924 wq_entry: &waiters[i].wait);
925 if (undo_auto_reset && waiters[i].activated &&
926 waiters[i].event && waiters[i].event->auto_reset)
927 set_event(waiters[i].event);
928 spin_unlock(lock: &waiters[i].event->lock);
929 }
930
931 kfree(objp: waiters);
932}
933
934int kfd_wait_on_events(struct kfd_process *p,
935 uint32_t num_events, void __user *data,
936 bool all, uint32_t *user_timeout_ms,
937 uint32_t *wait_result)
938{
939 struct kfd_event_data __user *events =
940 (struct kfd_event_data __user *) data;
941 uint32_t i;
942 int ret = 0;
943
944 struct kfd_event_waiter *event_waiters = NULL;
945 long timeout = user_timeout_to_jiffies(user_timeout_ms: *user_timeout_ms);
946
947 event_waiters = alloc_event_waiters(num_events);
948 if (!event_waiters) {
949 ret = -ENOMEM;
950 goto out;
951 }
952
953 /* Use p->event_mutex here to protect against concurrent creation and
954 * destruction of events while we initialize event_waiters.
955 */
956 mutex_lock(&p->event_mutex);
957
958 for (i = 0; i < num_events; i++) {
959 struct kfd_event_data event_data;
960
961 if (copy_from_user(to: &event_data, from: &events[i],
962 n: sizeof(struct kfd_event_data))) {
963 ret = -EFAULT;
964 goto out_unlock;
965 }
966
967 ret = init_event_waiter(p, waiter: &event_waiters[i], event_data: &event_data);
968 if (ret)
969 goto out_unlock;
970 }
971
972 /* Check condition once. */
973 *wait_result = test_event_condition(all, num_events, event_waiters);
974 if (*wait_result == KFD_IOC_WAIT_RESULT_COMPLETE) {
975 ret = copy_signaled_event_data(num_events,
976 event_waiters, data: events);
977 goto out_unlock;
978 } else if (WARN_ON(*wait_result == KFD_IOC_WAIT_RESULT_FAIL)) {
979 /* This should not happen. Events shouldn't be
980 * destroyed while we're holding the event_mutex
981 */
982 goto out_unlock;
983 }
984
985 mutex_unlock(lock: &p->event_mutex);
986
987 while (true) {
988 if (fatal_signal_pending(current)) {
989 ret = -EINTR;
990 break;
991 }
992
993 if (signal_pending(current)) {
994 ret = -ERESTARTSYS;
995 if (*user_timeout_ms != KFD_EVENT_TIMEOUT_IMMEDIATE &&
996 *user_timeout_ms != KFD_EVENT_TIMEOUT_INFINITE)
997 *user_timeout_ms = jiffies_to_msecs(
998 max(0l, timeout-1));
999 break;
1000 }
1001
1002 /* Set task state to interruptible sleep before
1003 * checking wake-up conditions. A concurrent wake-up
1004 * will put the task back into runnable state. In that
1005 * case schedule_timeout will not put the task to
1006 * sleep and we'll get a chance to re-check the
1007 * updated conditions almost immediately. Otherwise,
1008 * this race condition would lead to a soft hang or a
1009 * very long sleep.
1010 */
1011 set_current_state(TASK_INTERRUPTIBLE);
1012
1013 *wait_result = test_event_condition(all, num_events,
1014 event_waiters);
1015 if (*wait_result != KFD_IOC_WAIT_RESULT_TIMEOUT)
1016 break;
1017
1018 if (timeout <= 0)
1019 break;
1020
1021 timeout = schedule_timeout(timeout);
1022 }
1023 __set_current_state(TASK_RUNNING);
1024
1025 mutex_lock(&p->event_mutex);
1026 /* copy_signaled_event_data may sleep. So this has to happen
1027 * after the task state is set back to RUNNING.
1028 *
1029 * The event may also have been destroyed after signaling. So
1030 * copy_signaled_event_data also must confirm that the event
1031 * still exists. Therefore this must be under the p->event_mutex
1032 * which is also held when events are destroyed.
1033 */
1034 if (!ret && *wait_result == KFD_IOC_WAIT_RESULT_COMPLETE)
1035 ret = copy_signaled_event_data(num_events,
1036 event_waiters, data: events);
1037
1038out_unlock:
1039 free_waiters(num_events, waiters: event_waiters, undo_auto_reset: ret == -ERESTARTSYS);
1040 mutex_unlock(lock: &p->event_mutex);
1041out:
1042 if (ret)
1043 *wait_result = KFD_IOC_WAIT_RESULT_FAIL;
1044 else if (*wait_result == KFD_IOC_WAIT_RESULT_FAIL)
1045 ret = -EIO;
1046
1047 return ret;
1048}
1049
1050int kfd_event_mmap(struct kfd_process *p, struct vm_area_struct *vma)
1051{
1052 unsigned long pfn;
1053 struct kfd_signal_page *page;
1054 int ret;
1055
1056 /* check required size doesn't exceed the allocated size */
1057 if (get_order(KFD_SIGNAL_EVENT_LIMIT * 8) <
1058 get_order(size: vma->vm_end - vma->vm_start)) {
1059 pr_err("Event page mmap requested illegal size\n");
1060 return -EINVAL;
1061 }
1062
1063 page = p->signal_page;
1064 if (!page) {
1065 /* Probably KFD bug, but mmap is user-accessible. */
1066 pr_debug("Signal page could not be found\n");
1067 return -EINVAL;
1068 }
1069
1070 pfn = __pa(page->kernel_address);
1071 pfn >>= PAGE_SHIFT;
1072
1073 vm_flags_set(vma, VM_IO | VM_DONTCOPY | VM_DONTEXPAND | VM_NORESERVE
1074 | VM_DONTDUMP | VM_PFNMAP);
1075
1076 pr_debug("Mapping signal page\n");
1077 pr_debug(" start user address == 0x%08lx\n", vma->vm_start);
1078 pr_debug(" end user address == 0x%08lx\n", vma->vm_end);
1079 pr_debug(" pfn == 0x%016lX\n", pfn);
1080 pr_debug(" vm_flags == 0x%08lX\n", vma->vm_flags);
1081 pr_debug(" size == 0x%08lX\n",
1082 vma->vm_end - vma->vm_start);
1083
1084 page->user_address = (uint64_t __user *)vma->vm_start;
1085
1086 /* mapping the page to user process */
1087 ret = remap_pfn_range(vma, addr: vma->vm_start, pfn,
1088 size: vma->vm_end - vma->vm_start, vma->vm_page_prot);
1089 if (!ret)
1090 p->signal_mapped_size = vma->vm_end - vma->vm_start;
1091
1092 return ret;
1093}
1094
1095/*
1096 * Assumes that p is not going away.
1097 */
1098static void lookup_events_by_type_and_signal(struct kfd_process *p,
1099 int type, void *event_data)
1100{
1101 struct kfd_hsa_memory_exception_data *ev_data;
1102 struct kfd_event *ev;
1103 uint32_t id;
1104 bool send_signal = true;
1105
1106 ev_data = (struct kfd_hsa_memory_exception_data *) event_data;
1107
1108 rcu_read_lock();
1109
1110 id = KFD_FIRST_NONSIGNAL_EVENT_ID;
1111 idr_for_each_entry_continue(&p->event_idr, ev, id)
1112 if (ev->type == type) {
1113 send_signal = false;
1114 dev_dbg(kfd_device,
1115 "Event found: id %X type %d",
1116 ev->event_id, ev->type);
1117 spin_lock(lock: &ev->lock);
1118 set_event(ev);
1119 if (ev->type == KFD_EVENT_TYPE_MEMORY && ev_data)
1120 ev->memory_exception_data = *ev_data;
1121 spin_unlock(lock: &ev->lock);
1122 }
1123
1124 if (type == KFD_EVENT_TYPE_MEMORY) {
1125 dev_warn(kfd_device,
1126 "Sending SIGSEGV to process %d (pasid 0x%x)",
1127 p->lead_thread->pid, p->pasid);
1128 send_sig(SIGSEGV, p->lead_thread, 0);
1129 }
1130
1131 /* Send SIGTERM no event of type "type" has been found*/
1132 if (send_signal) {
1133 if (send_sigterm) {
1134 dev_warn(kfd_device,
1135 "Sending SIGTERM to process %d (pasid 0x%x)",
1136 p->lead_thread->pid, p->pasid);
1137 send_sig(SIGTERM, p->lead_thread, 0);
1138 } else {
1139 dev_err(kfd_device,
1140 "Process %d (pasid 0x%x) got unhandled exception",
1141 p->lead_thread->pid, p->pasid);
1142 }
1143 }
1144
1145 rcu_read_unlock();
1146}
1147
1148void kfd_signal_hw_exception_event(u32 pasid)
1149{
1150 /*
1151 * Because we are called from arbitrary context (workqueue) as opposed
1152 * to process context, kfd_process could attempt to exit while we are
1153 * running so the lookup function increments the process ref count.
1154 */
1155 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
1156
1157 if (!p)
1158 return; /* Presumably process exited. */
1159
1160 lookup_events_by_type_and_signal(p, KFD_EVENT_TYPE_HW_EXCEPTION, NULL);
1161 kfd_unref_process(p);
1162}
1163
1164void kfd_signal_vm_fault_event(struct kfd_node *dev, u32 pasid,
1165 struct kfd_vm_fault_info *info,
1166 struct kfd_hsa_memory_exception_data *data)
1167{
1168 struct kfd_event *ev;
1169 uint32_t id;
1170 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
1171 struct kfd_hsa_memory_exception_data memory_exception_data;
1172 int user_gpu_id;
1173
1174 if (!p)
1175 return; /* Presumably process exited. */
1176
1177 user_gpu_id = kfd_process_get_user_gpu_id(p, actual_gpu_id: dev->id);
1178 if (unlikely(user_gpu_id == -EINVAL)) {
1179 WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
1180 return;
1181 }
1182
1183 /* SoC15 chips and onwards will pass in data from now on. */
1184 if (!data) {
1185 memset(&memory_exception_data, 0, sizeof(memory_exception_data));
1186 memory_exception_data.gpu_id = user_gpu_id;
1187 memory_exception_data.failure.imprecise = true;
1188
1189 /* Set failure reason */
1190 if (info) {
1191 memory_exception_data.va = (info->page_addr) <<
1192 PAGE_SHIFT;
1193 memory_exception_data.failure.NotPresent =
1194 info->prot_valid ? 1 : 0;
1195 memory_exception_data.failure.NoExecute =
1196 info->prot_exec ? 1 : 0;
1197 memory_exception_data.failure.ReadOnly =
1198 info->prot_write ? 1 : 0;
1199 memory_exception_data.failure.imprecise = 0;
1200 }
1201 }
1202
1203 rcu_read_lock();
1204
1205 id = KFD_FIRST_NONSIGNAL_EVENT_ID;
1206 idr_for_each_entry_continue(&p->event_idr, ev, id)
1207 if (ev->type == KFD_EVENT_TYPE_MEMORY) {
1208 spin_lock(lock: &ev->lock);
1209 ev->memory_exception_data = data ? *data :
1210 memory_exception_data;
1211 set_event(ev);
1212 spin_unlock(lock: &ev->lock);
1213 }
1214
1215 rcu_read_unlock();
1216 kfd_unref_process(p);
1217}
1218
1219void kfd_signal_reset_event(struct kfd_node *dev)
1220{
1221 struct kfd_hsa_hw_exception_data hw_exception_data;
1222 struct kfd_hsa_memory_exception_data memory_exception_data;
1223 struct kfd_process *p;
1224 struct kfd_event *ev;
1225 unsigned int temp;
1226 uint32_t id, idx;
1227 int reset_cause = atomic_read(v: &dev->sram_ecc_flag) ?
1228 KFD_HW_EXCEPTION_ECC :
1229 KFD_HW_EXCEPTION_GPU_HANG;
1230
1231 /* Whole gpu reset caused by GPU hang and memory is lost */
1232 memset(&hw_exception_data, 0, sizeof(hw_exception_data));
1233 hw_exception_data.memory_lost = 1;
1234 hw_exception_data.reset_cause = reset_cause;
1235
1236 memset(&memory_exception_data, 0, sizeof(memory_exception_data));
1237 memory_exception_data.ErrorType = KFD_MEM_ERR_SRAM_ECC;
1238 memory_exception_data.failure.imprecise = true;
1239
1240 idx = srcu_read_lock(ssp: &kfd_processes_srcu);
1241 hash_for_each_rcu(kfd_processes_table, temp, p, kfd_processes) {
1242 int user_gpu_id = kfd_process_get_user_gpu_id(p, actual_gpu_id: dev->id);
1243
1244 if (unlikely(user_gpu_id == -EINVAL)) {
1245 WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
1246 continue;
1247 }
1248
1249 rcu_read_lock();
1250
1251 id = KFD_FIRST_NONSIGNAL_EVENT_ID;
1252 idr_for_each_entry_continue(&p->event_idr, ev, id) {
1253 if (ev->type == KFD_EVENT_TYPE_HW_EXCEPTION) {
1254 spin_lock(lock: &ev->lock);
1255 ev->hw_exception_data = hw_exception_data;
1256 ev->hw_exception_data.gpu_id = user_gpu_id;
1257 set_event(ev);
1258 spin_unlock(lock: &ev->lock);
1259 }
1260 if (ev->type == KFD_EVENT_TYPE_MEMORY &&
1261 reset_cause == KFD_HW_EXCEPTION_ECC) {
1262 spin_lock(lock: &ev->lock);
1263 ev->memory_exception_data = memory_exception_data;
1264 ev->memory_exception_data.gpu_id = user_gpu_id;
1265 set_event(ev);
1266 spin_unlock(lock: &ev->lock);
1267 }
1268 }
1269
1270 rcu_read_unlock();
1271 }
1272 srcu_read_unlock(ssp: &kfd_processes_srcu, idx);
1273}
1274
1275void kfd_signal_poison_consumed_event(struct kfd_node *dev, u32 pasid)
1276{
1277 struct kfd_process *p = kfd_lookup_process_by_pasid(pasid);
1278 struct kfd_hsa_memory_exception_data memory_exception_data;
1279 struct kfd_hsa_hw_exception_data hw_exception_data;
1280 struct kfd_event *ev;
1281 uint32_t id = KFD_FIRST_NONSIGNAL_EVENT_ID;
1282 int user_gpu_id;
1283
1284 if (!p)
1285 return; /* Presumably process exited. */
1286
1287 user_gpu_id = kfd_process_get_user_gpu_id(p, actual_gpu_id: dev->id);
1288 if (unlikely(user_gpu_id == -EINVAL)) {
1289 WARN_ONCE(1, "Could not get user_gpu_id from dev->id:%x\n", dev->id);
1290 return;
1291 }
1292
1293 memset(&hw_exception_data, 0, sizeof(hw_exception_data));
1294 hw_exception_data.gpu_id = user_gpu_id;
1295 hw_exception_data.memory_lost = 1;
1296 hw_exception_data.reset_cause = KFD_HW_EXCEPTION_ECC;
1297
1298 memset(&memory_exception_data, 0, sizeof(memory_exception_data));
1299 memory_exception_data.ErrorType = KFD_MEM_ERR_POISON_CONSUMED;
1300 memory_exception_data.gpu_id = user_gpu_id;
1301 memory_exception_data.failure.imprecise = true;
1302
1303 rcu_read_lock();
1304
1305 idr_for_each_entry_continue(&p->event_idr, ev, id) {
1306 if (ev->type == KFD_EVENT_TYPE_HW_EXCEPTION) {
1307 spin_lock(lock: &ev->lock);
1308 ev->hw_exception_data = hw_exception_data;
1309 set_event(ev);
1310 spin_unlock(lock: &ev->lock);
1311 }
1312
1313 if (ev->type == KFD_EVENT_TYPE_MEMORY) {
1314 spin_lock(lock: &ev->lock);
1315 ev->memory_exception_data = memory_exception_data;
1316 set_event(ev);
1317 spin_unlock(lock: &ev->lock);
1318 }
1319 }
1320
1321 rcu_read_unlock();
1322
1323 /* user application will handle SIGBUS signal */
1324 send_sig(SIGBUS, p->lead_thread, 0);
1325
1326 kfd_unref_process(p);
1327}
1328

source code of linux/drivers/gpu/drm/amd/amdkfd/kfd_events.c