1 /*
2 * Copyright 2018 Red Hat Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 */
22 #include "nouveau_svm.h"
23 #include "nouveau_drv.h"
24 #include "nouveau_chan.h"
25 #include "nouveau_dmem.h"
26
27 #include <nvif/event.h>
28 #include <nvif/object.h>
29 #include <nvif/vmm.h>
30
31 #include <nvif/class.h>
32 #include <nvif/clb069.h>
33 #include <nvif/ifc00d.h>
34
35 #include <linux/sched/mm.h>
36 #include <linux/sort.h>
37 #include <linux/hmm.h>
38 #include <linux/memremap.h>
39 #include <linux/rmap.h>
40
41 struct nouveau_svm {
42 struct nouveau_drm *drm;
43 struct mutex mutex;
44 struct list_head inst;
45
46 struct nouveau_svm_fault_buffer {
47 int id;
48 struct nvif_object object;
49 u32 entries;
50 u32 getaddr;
51 u32 putaddr;
52 u32 get;
53 u32 put;
54 struct nvif_event notify;
55 struct work_struct work;
56
57 struct nouveau_svm_fault {
58 u64 inst;
59 u64 addr;
60 u64 time;
61 u32 engine;
62 u8 gpc;
63 u8 hub;
64 u8 access;
65 u8 client;
66 u8 fault;
67 struct nouveau_svmm *svmm;
68 } **fault;
69 int fault_nr;
70 } buffer[];
71 };
72
73 #define FAULT_ACCESS_READ 0
74 #define FAULT_ACCESS_WRITE 1
75 #define FAULT_ACCESS_ATOMIC 2
76 #define FAULT_ACCESS_PREFETCH 3
77
78 #define SVM_DBG(s,f,a...) NV_DEBUG((s)->drm, "svm: "f"\n", ##a)
79 #define SVM_ERR(s,f,a...) NV_WARN((s)->drm, "svm: "f"\n", ##a)
80
81 struct nouveau_pfnmap_args {
82 struct nvif_ioctl_v0 i;
83 struct nvif_ioctl_mthd_v0 m;
84 struct nvif_vmm_pfnmap_v0 p;
85 };
86
87 struct nouveau_ivmm {
88 struct nouveau_svmm *svmm;
89 u64 inst;
90 struct list_head head;
91 };
92
93 static struct nouveau_ivmm *
nouveau_ivmm_find(struct nouveau_svm * svm,u64 inst)94 nouveau_ivmm_find(struct nouveau_svm *svm, u64 inst)
95 {
96 struct nouveau_ivmm *ivmm;
97 list_for_each_entry(ivmm, &svm->inst, head) {
98 if (ivmm->inst == inst)
99 return ivmm;
100 }
101 return NULL;
102 }
103
104 #define SVMM_DBG(s,f,a...) \
105 NV_DEBUG((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)
106 #define SVMM_ERR(s,f,a...) \
107 NV_WARN((s)->vmm->cli->drm, "svm-%p: "f"\n", (s), ##a)
108
109 int
nouveau_svmm_bind(struct drm_device * dev,void * data,struct drm_file * file_priv)110 nouveau_svmm_bind(struct drm_device *dev, void *data,
111 struct drm_file *file_priv)
112 {
113 struct nouveau_cli *cli = nouveau_cli(file_priv);
114 struct drm_nouveau_svm_bind *args = data;
115 unsigned target, cmd;
116 unsigned long addr, end;
117 struct mm_struct *mm;
118
119 args->va_start &= PAGE_MASK;
120 args->va_end = ALIGN(args->va_end, PAGE_SIZE);
121
122 /* Sanity check arguments */
123 if (args->reserved0 || args->reserved1)
124 return -EINVAL;
125 if (args->header & (~NOUVEAU_SVM_BIND_VALID_MASK))
126 return -EINVAL;
127 if (args->va_start >= args->va_end)
128 return -EINVAL;
129
130 cmd = args->header >> NOUVEAU_SVM_BIND_COMMAND_SHIFT;
131 cmd &= NOUVEAU_SVM_BIND_COMMAND_MASK;
132 switch (cmd) {
133 case NOUVEAU_SVM_BIND_COMMAND__MIGRATE:
134 break;
135 default:
136 return -EINVAL;
137 }
138
139 /* FIXME support CPU target ie all target value < GPU_VRAM */
140 target = args->header >> NOUVEAU_SVM_BIND_TARGET_SHIFT;
141 target &= NOUVEAU_SVM_BIND_TARGET_MASK;
142 switch (target) {
143 case NOUVEAU_SVM_BIND_TARGET__GPU_VRAM:
144 break;
145 default:
146 return -EINVAL;
147 }
148
149 /*
150 * FIXME: For now refuse non 0 stride, we need to change the migrate
151 * kernel function to handle stride to avoid to create a mess within
152 * each device driver.
153 */
154 if (args->stride)
155 return -EINVAL;
156
157 /*
158 * Ok we are ask to do something sane, for now we only support migrate
159 * commands but we will add things like memory policy (what to do on
160 * page fault) and maybe some other commands.
161 */
162
163 mm = get_task_mm(current);
164 if (!mm) {
165 return -EINVAL;
166 }
167 mmap_read_lock(mm);
168
169 if (!cli->svm.svmm) {
170 mmap_read_unlock(mm);
171 mmput(mm);
172 return -EINVAL;
173 }
174
175 for (addr = args->va_start, end = args->va_end; addr < end;) {
176 struct vm_area_struct *vma;
177 unsigned long next;
178
179 vma = find_vma_intersection(mm, addr, end);
180 if (!vma)
181 break;
182
183 addr = max(addr, vma->vm_start);
184 next = min(vma->vm_end, end);
185 /* This is a best effort so we ignore errors */
186 nouveau_dmem_migrate_vma(cli->drm, cli->svm.svmm, vma, addr,
187 next);
188 addr = next;
189 }
190
191 /*
192 * FIXME Return the number of page we have migrated, again we need to
193 * update the migrate API to return that information so that we can
194 * report it to user space.
195 */
196 args->result = 0;
197
198 mmap_read_unlock(mm);
199 mmput(mm);
200
201 return 0;
202 }
203
204 /* Unlink channel instance from SVMM. */
205 void
nouveau_svmm_part(struct nouveau_svmm * svmm,u64 inst)206 nouveau_svmm_part(struct nouveau_svmm *svmm, u64 inst)
207 {
208 struct nouveau_ivmm *ivmm;
209 if (svmm) {
210 mutex_lock(&svmm->vmm->cli->drm->svm->mutex);
211 ivmm = nouveau_ivmm_find(svmm->vmm->cli->drm->svm, inst);
212 if (ivmm) {
213 list_del(&ivmm->head);
214 kfree(ivmm);
215 }
216 mutex_unlock(&svmm->vmm->cli->drm->svm->mutex);
217 }
218 }
219
220 /* Link channel instance to SVMM. */
221 int
nouveau_svmm_join(struct nouveau_svmm * svmm,u64 inst)222 nouveau_svmm_join(struct nouveau_svmm *svmm, u64 inst)
223 {
224 struct nouveau_ivmm *ivmm;
225 if (svmm) {
226 if (!(ivmm = kmalloc(sizeof(*ivmm), GFP_KERNEL)))
227 return -ENOMEM;
228 ivmm->svmm = svmm;
229 ivmm->inst = inst;
230
231 mutex_lock(&svmm->vmm->cli->drm->svm->mutex);
232 list_add(&ivmm->head, &svmm->vmm->cli->drm->svm->inst);
233 mutex_unlock(&svmm->vmm->cli->drm->svm->mutex);
234 }
235 return 0;
236 }
237
238 /* Invalidate SVMM address-range on GPU. */
239 void
nouveau_svmm_invalidate(struct nouveau_svmm * svmm,u64 start,u64 limit)240 nouveau_svmm_invalidate(struct nouveau_svmm *svmm, u64 start, u64 limit)
241 {
242 if (limit > start) {
243 nvif_object_mthd(&svmm->vmm->vmm.object, NVIF_VMM_V0_PFNCLR,
244 &(struct nvif_vmm_pfnclr_v0) {
245 .addr = start,
246 .size = limit - start,
247 }, sizeof(struct nvif_vmm_pfnclr_v0));
248 }
249 }
250
251 static int
nouveau_svmm_invalidate_range_start(struct mmu_notifier * mn,const struct mmu_notifier_range * update)252 nouveau_svmm_invalidate_range_start(struct mmu_notifier *mn,
253 const struct mmu_notifier_range *update)
254 {
255 struct nouveau_svmm *svmm =
256 container_of(mn, struct nouveau_svmm, notifier);
257 unsigned long start = update->start;
258 unsigned long limit = update->end;
259
260 if (!mmu_notifier_range_blockable(update))
261 return -EAGAIN;
262
263 SVMM_DBG(svmm, "invalidate %016lx-%016lx", start, limit);
264
265 mutex_lock(&svmm->mutex);
266 if (unlikely(!svmm->vmm))
267 goto out;
268
269 /*
270 * Ignore invalidation callbacks for device private pages since
271 * the invalidation is handled as part of the migration process.
272 */
273 if (update->event == MMU_NOTIFY_MIGRATE &&
274 update->owner == svmm->vmm->cli->drm->dev)
275 goto out;
276
277 if (limit > svmm->unmanaged.start && start < svmm->unmanaged.limit) {
278 if (start < svmm->unmanaged.start) {
279 nouveau_svmm_invalidate(svmm, start,
280 svmm->unmanaged.limit);
281 }
282 start = svmm->unmanaged.limit;
283 }
284
285 nouveau_svmm_invalidate(svmm, start, limit);
286
287 out:
288 mutex_unlock(&svmm->mutex);
289 return 0;
290 }
291
nouveau_svmm_free_notifier(struct mmu_notifier * mn)292 static void nouveau_svmm_free_notifier(struct mmu_notifier *mn)
293 {
294 kfree(container_of(mn, struct nouveau_svmm, notifier));
295 }
296
297 static const struct mmu_notifier_ops nouveau_mn_ops = {
298 .invalidate_range_start = nouveau_svmm_invalidate_range_start,
299 .free_notifier = nouveau_svmm_free_notifier,
300 };
301
302 void
nouveau_svmm_fini(struct nouveau_svmm ** psvmm)303 nouveau_svmm_fini(struct nouveau_svmm **psvmm)
304 {
305 struct nouveau_svmm *svmm = *psvmm;
306 if (svmm) {
307 mutex_lock(&svmm->mutex);
308 svmm->vmm = NULL;
309 mutex_unlock(&svmm->mutex);
310 mmu_notifier_put(&svmm->notifier);
311 *psvmm = NULL;
312 }
313 }
314
315 int
nouveau_svmm_init(struct drm_device * dev,void * data,struct drm_file * file_priv)316 nouveau_svmm_init(struct drm_device *dev, void *data,
317 struct drm_file *file_priv)
318 {
319 struct nouveau_cli *cli = nouveau_cli(file_priv);
320 struct nouveau_svmm *svmm;
321 struct drm_nouveau_svm_init *args = data;
322 int ret;
323
324 /* We need to fail if svm is disabled */
325 if (!cli->drm->svm)
326 return -ENOSYS;
327
328 /* Allocate tracking for SVM-enabled VMM. */
329 if (!(svmm = kzalloc(sizeof(*svmm), GFP_KERNEL)))
330 return -ENOMEM;
331 svmm->vmm = &cli->svm;
332 svmm->unmanaged.start = args->unmanaged_addr;
333 svmm->unmanaged.limit = args->unmanaged_addr + args->unmanaged_size;
334 mutex_init(&svmm->mutex);
335
336 /* Check that SVM isn't already enabled for the client. */
337 mutex_lock(&cli->mutex);
338 if (cli->svm.cli) {
339 ret = -EBUSY;
340 goto out_free;
341 }
342
343 /* Allocate a new GPU VMM that can support SVM (managed by the
344 * client, with replayable faults enabled).
345 *
346 * All future channel/memory allocations will make use of this
347 * VMM instead of the standard one.
348 */
349 ret = nvif_vmm_ctor(&cli->mmu, "svmVmm",
350 cli->vmm.vmm.object.oclass, MANAGED,
351 args->unmanaged_addr, args->unmanaged_size,
352 &(struct gp100_vmm_v0) {
353 .fault_replay = true,
354 }, sizeof(struct gp100_vmm_v0), &cli->svm.vmm);
355 if (ret)
356 goto out_free;
357
358 mmap_write_lock(current->mm);
359 svmm->notifier.ops = &nouveau_mn_ops;
360 ret = __mmu_notifier_register(&svmm->notifier, current->mm);
361 if (ret)
362 goto out_mm_unlock;
363 /* Note, ownership of svmm transfers to mmu_notifier */
364
365 cli->svm.svmm = svmm;
366 cli->svm.cli = cli;
367 mmap_write_unlock(current->mm);
368 mutex_unlock(&cli->mutex);
369 return 0;
370
371 out_mm_unlock:
372 mmap_write_unlock(current->mm);
373 out_free:
374 mutex_unlock(&cli->mutex);
375 kfree(svmm);
376 return ret;
377 }
378
379 /* Issue fault replay for GPU to retry accesses that faulted previously. */
380 static void
nouveau_svm_fault_replay(struct nouveau_svm * svm)381 nouveau_svm_fault_replay(struct nouveau_svm *svm)
382 {
383 SVM_DBG(svm, "replay");
384 WARN_ON(nvif_object_mthd(&svm->drm->client.vmm.vmm.object,
385 GP100_VMM_VN_FAULT_REPLAY,
386 &(struct gp100_vmm_fault_replay_vn) {},
387 sizeof(struct gp100_vmm_fault_replay_vn)));
388 }
389
390 /* Cancel a replayable fault that could not be handled.
391 *
392 * Cancelling the fault will trigger recovery to reset the engine
393 * and kill the offending channel (ie. GPU SIGSEGV).
394 */
395 static void
nouveau_svm_fault_cancel(struct nouveau_svm * svm,u64 inst,u8 hub,u8 gpc,u8 client)396 nouveau_svm_fault_cancel(struct nouveau_svm *svm,
397 u64 inst, u8 hub, u8 gpc, u8 client)
398 {
399 SVM_DBG(svm, "cancel %016llx %d %02x %02x", inst, hub, gpc, client);
400 WARN_ON(nvif_object_mthd(&svm->drm->client.vmm.vmm.object,
401 GP100_VMM_VN_FAULT_CANCEL,
402 &(struct gp100_vmm_fault_cancel_v0) {
403 .hub = hub,
404 .gpc = gpc,
405 .client = client,
406 .inst = inst,
407 }, sizeof(struct gp100_vmm_fault_cancel_v0)));
408 }
409
410 static void
nouveau_svm_fault_cancel_fault(struct nouveau_svm * svm,struct nouveau_svm_fault * fault)411 nouveau_svm_fault_cancel_fault(struct nouveau_svm *svm,
412 struct nouveau_svm_fault *fault)
413 {
414 nouveau_svm_fault_cancel(svm, fault->inst,
415 fault->hub,
416 fault->gpc,
417 fault->client);
418 }
419
420 static int
nouveau_svm_fault_priority(u8 fault)421 nouveau_svm_fault_priority(u8 fault)
422 {
423 switch (fault) {
424 case FAULT_ACCESS_PREFETCH:
425 return 0;
426 case FAULT_ACCESS_READ:
427 return 1;
428 case FAULT_ACCESS_WRITE:
429 return 2;
430 case FAULT_ACCESS_ATOMIC:
431 return 3;
432 default:
433 WARN_ON_ONCE(1);
434 return -1;
435 }
436 }
437
438 static int
nouveau_svm_fault_cmp(const void * a,const void * b)439 nouveau_svm_fault_cmp(const void *a, const void *b)
440 {
441 const struct nouveau_svm_fault *fa = *(struct nouveau_svm_fault **)a;
442 const struct nouveau_svm_fault *fb = *(struct nouveau_svm_fault **)b;
443 int ret;
444 if ((ret = (s64)fa->inst - fb->inst))
445 return ret;
446 if ((ret = (s64)fa->addr - fb->addr))
447 return ret;
448 return nouveau_svm_fault_priority(fa->access) -
449 nouveau_svm_fault_priority(fb->access);
450 }
451
452 static void
nouveau_svm_fault_cache(struct nouveau_svm * svm,struct nouveau_svm_fault_buffer * buffer,u32 offset)453 nouveau_svm_fault_cache(struct nouveau_svm *svm,
454 struct nouveau_svm_fault_buffer *buffer, u32 offset)
455 {
456 struct nvif_object *memory = &buffer->object;
457 const u32 instlo = nvif_rd32(memory, offset + 0x00);
458 const u32 insthi = nvif_rd32(memory, offset + 0x04);
459 const u32 addrlo = nvif_rd32(memory, offset + 0x08);
460 const u32 addrhi = nvif_rd32(memory, offset + 0x0c);
461 const u32 timelo = nvif_rd32(memory, offset + 0x10);
462 const u32 timehi = nvif_rd32(memory, offset + 0x14);
463 const u32 engine = nvif_rd32(memory, offset + 0x18);
464 const u32 info = nvif_rd32(memory, offset + 0x1c);
465 const u64 inst = (u64)insthi << 32 | instlo;
466 const u8 gpc = (info & 0x1f000000) >> 24;
467 const u8 hub = (info & 0x00100000) >> 20;
468 const u8 client = (info & 0x00007f00) >> 8;
469 struct nouveau_svm_fault *fault;
470
471 //XXX: i think we're supposed to spin waiting */
472 if (WARN_ON(!(info & 0x80000000)))
473 return;
474
475 nvif_mask(memory, offset + 0x1c, 0x80000000, 0x00000000);
476
477 if (!buffer->fault[buffer->fault_nr]) {
478 fault = kmalloc(sizeof(*fault), GFP_KERNEL);
479 if (WARN_ON(!fault)) {
480 nouveau_svm_fault_cancel(svm, inst, hub, gpc, client);
481 return;
482 }
483 buffer->fault[buffer->fault_nr] = fault;
484 }
485
486 fault = buffer->fault[buffer->fault_nr++];
487 fault->inst = inst;
488 fault->addr = (u64)addrhi << 32 | addrlo;
489 fault->time = (u64)timehi << 32 | timelo;
490 fault->engine = engine;
491 fault->gpc = gpc;
492 fault->hub = hub;
493 fault->access = (info & 0x000f0000) >> 16;
494 fault->client = client;
495 fault->fault = (info & 0x0000001f);
496
497 SVM_DBG(svm, "fault %016llx %016llx %02x",
498 fault->inst, fault->addr, fault->access);
499 }
500
501 struct svm_notifier {
502 struct mmu_interval_notifier notifier;
503 struct nouveau_svmm *svmm;
504 };
505
nouveau_svm_range_invalidate(struct mmu_interval_notifier * mni,const struct mmu_notifier_range * range,unsigned long cur_seq)506 static bool nouveau_svm_range_invalidate(struct mmu_interval_notifier *mni,
507 const struct mmu_notifier_range *range,
508 unsigned long cur_seq)
509 {
510 struct svm_notifier *sn =
511 container_of(mni, struct svm_notifier, notifier);
512
513 if (range->event == MMU_NOTIFY_EXCLUSIVE &&
514 range->owner == sn->svmm->vmm->cli->drm->dev)
515 return true;
516
517 /*
518 * serializes the update to mni->invalidate_seq done by caller and
519 * prevents invalidation of the PTE from progressing while HW is being
520 * programmed. This is very hacky and only works because the normal
521 * notifier that does invalidation is always called after the range
522 * notifier.
523 */
524 if (mmu_notifier_range_blockable(range))
525 mutex_lock(&sn->svmm->mutex);
526 else if (!mutex_trylock(&sn->svmm->mutex))
527 return false;
528 mmu_interval_set_seq(mni, cur_seq);
529 mutex_unlock(&sn->svmm->mutex);
530 return true;
531 }
532
533 static const struct mmu_interval_notifier_ops nouveau_svm_mni_ops = {
534 .invalidate = nouveau_svm_range_invalidate,
535 };
536
nouveau_hmm_convert_pfn(struct nouveau_drm * drm,struct hmm_range * range,struct nouveau_pfnmap_args * args)537 static void nouveau_hmm_convert_pfn(struct nouveau_drm *drm,
538 struct hmm_range *range,
539 struct nouveau_pfnmap_args *args)
540 {
541 struct page *page;
542
543 /*
544 * The address prepared here is passed through nvif_object_ioctl()
545 * to an eventual DMA map in something like gp100_vmm_pgt_pfn()
546 *
547 * This is all just encoding the internal hmm representation into a
548 * different nouveau internal representation.
549 */
550 if (!(range->hmm_pfns[0] & HMM_PFN_VALID)) {
551 args->p.phys[0] = 0;
552 return;
553 }
554
555 page = hmm_pfn_to_page(range->hmm_pfns[0]);
556 /*
557 * Only map compound pages to the GPU if the CPU is also mapping the
558 * page as a compound page. Otherwise, the PTE protections might not be
559 * consistent (e.g., CPU only maps part of a compound page).
560 * Note that the underlying page might still be larger than the
561 * CPU mapping (e.g., a PUD sized compound page partially mapped with
562 * a PMD sized page table entry).
563 */
564 if (hmm_pfn_to_map_order(range->hmm_pfns[0])) {
565 unsigned long addr = args->p.addr;
566
567 args->p.page = hmm_pfn_to_map_order(range->hmm_pfns[0]) +
568 PAGE_SHIFT;
569 args->p.size = 1UL << args->p.page;
570 args->p.addr &= ~(args->p.size - 1);
571 page -= (addr - args->p.addr) >> PAGE_SHIFT;
572 }
573 if (is_device_private_page(page))
574 args->p.phys[0] = nouveau_dmem_page_addr(page) |
575 NVIF_VMM_PFNMAP_V0_V |
576 NVIF_VMM_PFNMAP_V0_VRAM;
577 else
578 args->p.phys[0] = page_to_phys(page) |
579 NVIF_VMM_PFNMAP_V0_V |
580 NVIF_VMM_PFNMAP_V0_HOST;
581 if (range->hmm_pfns[0] & HMM_PFN_WRITE)
582 args->p.phys[0] |= NVIF_VMM_PFNMAP_V0_W;
583 }
584
nouveau_atomic_range_fault(struct nouveau_svmm * svmm,struct nouveau_drm * drm,struct nouveau_pfnmap_args * args,u32 size,struct svm_notifier * notifier)585 static int nouveau_atomic_range_fault(struct nouveau_svmm *svmm,
586 struct nouveau_drm *drm,
587 struct nouveau_pfnmap_args *args, u32 size,
588 struct svm_notifier *notifier)
589 {
590 unsigned long timeout =
591 jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
592 struct mm_struct *mm = svmm->notifier.mm;
593 struct folio *folio;
594 struct page *page;
595 unsigned long start = args->p.addr;
596 unsigned long notifier_seq;
597 int ret = 0;
598
599 ret = mmu_interval_notifier_insert(¬ifier->notifier, mm,
600 args->p.addr, args->p.size,
601 &nouveau_svm_mni_ops);
602 if (ret)
603 return ret;
604
605 while (true) {
606 if (time_after(jiffies, timeout)) {
607 ret = -EBUSY;
608 goto out;
609 }
610
611 notifier_seq = mmu_interval_read_begin(¬ifier->notifier);
612 mmap_read_lock(mm);
613 ret = make_device_exclusive_range(mm, start, start + PAGE_SIZE,
614 &page, drm->dev);
615 mmap_read_unlock(mm);
616 if (ret <= 0 || !page) {
617 ret = -EINVAL;
618 goto out;
619 }
620 folio = page_folio(page);
621
622 mutex_lock(&svmm->mutex);
623 if (!mmu_interval_read_retry(¬ifier->notifier,
624 notifier_seq))
625 break;
626 mutex_unlock(&svmm->mutex);
627
628 folio_unlock(folio);
629 folio_put(folio);
630 }
631
632 /* Map the page on the GPU. */
633 args->p.page = 12;
634 args->p.size = PAGE_SIZE;
635 args->p.addr = start;
636 args->p.phys[0] = page_to_phys(page) |
637 NVIF_VMM_PFNMAP_V0_V |
638 NVIF_VMM_PFNMAP_V0_W |
639 NVIF_VMM_PFNMAP_V0_A |
640 NVIF_VMM_PFNMAP_V0_HOST;
641
642 ret = nvif_object_ioctl(&svmm->vmm->vmm.object, args, size, NULL);
643 mutex_unlock(&svmm->mutex);
644
645 folio_unlock(folio);
646 folio_put(folio);
647
648 out:
649 mmu_interval_notifier_remove(¬ifier->notifier);
650 return ret;
651 }
652
nouveau_range_fault(struct nouveau_svmm * svmm,struct nouveau_drm * drm,struct nouveau_pfnmap_args * args,u32 size,unsigned long hmm_flags,struct svm_notifier * notifier)653 static int nouveau_range_fault(struct nouveau_svmm *svmm,
654 struct nouveau_drm *drm,
655 struct nouveau_pfnmap_args *args, u32 size,
656 unsigned long hmm_flags,
657 struct svm_notifier *notifier)
658 {
659 unsigned long timeout =
660 jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
661 /* Have HMM fault pages within the fault window to the GPU. */
662 unsigned long hmm_pfns[1];
663 struct hmm_range range = {
664 .notifier = ¬ifier->notifier,
665 .default_flags = hmm_flags,
666 .hmm_pfns = hmm_pfns,
667 .dev_private_owner = drm->dev,
668 };
669 struct mm_struct *mm = svmm->notifier.mm;
670 int ret;
671
672 ret = mmu_interval_notifier_insert(¬ifier->notifier, mm,
673 args->p.addr, args->p.size,
674 &nouveau_svm_mni_ops);
675 if (ret)
676 return ret;
677
678 range.start = notifier->notifier.interval_tree.start;
679 range.end = notifier->notifier.interval_tree.last + 1;
680
681 while (true) {
682 if (time_after(jiffies, timeout)) {
683 ret = -EBUSY;
684 goto out;
685 }
686
687 range.notifier_seq = mmu_interval_read_begin(range.notifier);
688 mmap_read_lock(mm);
689 ret = hmm_range_fault(&range);
690 mmap_read_unlock(mm);
691 if (ret) {
692 if (ret == -EBUSY)
693 continue;
694 goto out;
695 }
696
697 mutex_lock(&svmm->mutex);
698 if (mmu_interval_read_retry(range.notifier,
699 range.notifier_seq)) {
700 mutex_unlock(&svmm->mutex);
701 continue;
702 }
703 break;
704 }
705
706 nouveau_hmm_convert_pfn(drm, &range, args);
707
708 ret = nvif_object_ioctl(&svmm->vmm->vmm.object, args, size, NULL);
709 mutex_unlock(&svmm->mutex);
710
711 out:
712 mmu_interval_notifier_remove(¬ifier->notifier);
713
714 return ret;
715 }
716
717 static void
nouveau_svm_fault(struct work_struct * work)718 nouveau_svm_fault(struct work_struct *work)
719 {
720 struct nouveau_svm_fault_buffer *buffer = container_of(work, typeof(*buffer), work);
721 struct nouveau_svm *svm = container_of(buffer, typeof(*svm), buffer[buffer->id]);
722 struct nvif_object *device = &svm->drm->client.device.object;
723 struct nouveau_svmm *svmm;
724 struct {
725 struct nouveau_pfnmap_args i;
726 u64 phys[1];
727 } args;
728 unsigned long hmm_flags;
729 u64 inst, start, limit;
730 int fi, fn;
731 int replay = 0, atomic = 0, ret;
732
733 /* Parse available fault buffer entries into a cache, and update
734 * the GET pointer so HW can reuse the entries.
735 */
736 SVM_DBG(svm, "fault handler");
737 if (buffer->get == buffer->put) {
738 buffer->put = nvif_rd32(device, buffer->putaddr);
739 buffer->get = nvif_rd32(device, buffer->getaddr);
740 if (buffer->get == buffer->put)
741 return;
742 }
743 buffer->fault_nr = 0;
744
745 SVM_DBG(svm, "get %08x put %08x", buffer->get, buffer->put);
746 while (buffer->get != buffer->put) {
747 nouveau_svm_fault_cache(svm, buffer, buffer->get * 0x20);
748 if (++buffer->get == buffer->entries)
749 buffer->get = 0;
750 }
751 nvif_wr32(device, buffer->getaddr, buffer->get);
752 SVM_DBG(svm, "%d fault(s) pending", buffer->fault_nr);
753
754 /* Sort parsed faults by instance pointer to prevent unnecessary
755 * instance to SVMM translations, followed by address and access
756 * type to reduce the amount of work when handling the faults.
757 */
758 sort(buffer->fault, buffer->fault_nr, sizeof(*buffer->fault),
759 nouveau_svm_fault_cmp, NULL);
760
761 /* Lookup SVMM structure for each unique instance pointer. */
762 mutex_lock(&svm->mutex);
763 for (fi = 0, svmm = NULL; fi < buffer->fault_nr; fi++) {
764 if (!svmm || buffer->fault[fi]->inst != inst) {
765 struct nouveau_ivmm *ivmm =
766 nouveau_ivmm_find(svm, buffer->fault[fi]->inst);
767 svmm = ivmm ? ivmm->svmm : NULL;
768 inst = buffer->fault[fi]->inst;
769 SVM_DBG(svm, "inst %016llx -> svm-%p", inst, svmm);
770 }
771 buffer->fault[fi]->svmm = svmm;
772 }
773 mutex_unlock(&svm->mutex);
774
775 /* Process list of faults. */
776 args.i.i.version = 0;
777 args.i.i.type = NVIF_IOCTL_V0_MTHD;
778 args.i.m.version = 0;
779 args.i.m.method = NVIF_VMM_V0_PFNMAP;
780 args.i.p.version = 0;
781
782 for (fi = 0; fn = fi + 1, fi < buffer->fault_nr; fi = fn) {
783 struct svm_notifier notifier;
784 struct mm_struct *mm;
785
786 /* Cancel any faults from non-SVM channels. */
787 if (!(svmm = buffer->fault[fi]->svmm)) {
788 nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]);
789 continue;
790 }
791 SVMM_DBG(svmm, "addr %016llx", buffer->fault[fi]->addr);
792
793 /* We try and group handling of faults within a small
794 * window into a single update.
795 */
796 start = buffer->fault[fi]->addr;
797 limit = start + PAGE_SIZE;
798 if (start < svmm->unmanaged.limit)
799 limit = min_t(u64, limit, svmm->unmanaged.start);
800
801 /*
802 * Prepare the GPU-side update of all pages within the
803 * fault window, determining required pages and access
804 * permissions based on pending faults.
805 */
806 args.i.p.addr = start;
807 args.i.p.page = PAGE_SHIFT;
808 args.i.p.size = PAGE_SIZE;
809 /*
810 * Determine required permissions based on GPU fault
811 * access flags.
812 */
813 switch (buffer->fault[fi]->access) {
814 case 0: /* READ. */
815 hmm_flags = HMM_PFN_REQ_FAULT;
816 break;
817 case 2: /* ATOMIC. */
818 atomic = true;
819 break;
820 case 3: /* PREFETCH. */
821 hmm_flags = 0;
822 break;
823 default:
824 hmm_flags = HMM_PFN_REQ_FAULT | HMM_PFN_REQ_WRITE;
825 break;
826 }
827
828 mm = svmm->notifier.mm;
829 if (!mmget_not_zero(mm)) {
830 nouveau_svm_fault_cancel_fault(svm, buffer->fault[fi]);
831 continue;
832 }
833
834 notifier.svmm = svmm;
835 if (atomic)
836 ret = nouveau_atomic_range_fault(svmm, svm->drm,
837 &args.i, sizeof(args),
838 ¬ifier);
839 else
840 ret = nouveau_range_fault(svmm, svm->drm, &args.i,
841 sizeof(args), hmm_flags,
842 ¬ifier);
843 mmput(mm);
844
845 limit = args.i.p.addr + args.i.p.size;
846 for (fn = fi; ++fn < buffer->fault_nr; ) {
847 /* It's okay to skip over duplicate addresses from the
848 * same SVMM as faults are ordered by access type such
849 * that only the first one needs to be handled.
850 *
851 * ie. WRITE faults appear first, thus any handling of
852 * pending READ faults will already be satisfied.
853 * But if a large page is mapped, make sure subsequent
854 * fault addresses have sufficient access permission.
855 */
856 if (buffer->fault[fn]->svmm != svmm ||
857 buffer->fault[fn]->addr >= limit ||
858 (buffer->fault[fi]->access == FAULT_ACCESS_READ &&
859 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_V)) ||
860 (buffer->fault[fi]->access != FAULT_ACCESS_READ &&
861 buffer->fault[fi]->access != FAULT_ACCESS_PREFETCH &&
862 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_W)) ||
863 (buffer->fault[fi]->access != FAULT_ACCESS_READ &&
864 buffer->fault[fi]->access != FAULT_ACCESS_WRITE &&
865 buffer->fault[fi]->access != FAULT_ACCESS_PREFETCH &&
866 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_A)))
867 break;
868 }
869
870 /* If handling failed completely, cancel all faults. */
871 if (ret) {
872 while (fi < fn) {
873 struct nouveau_svm_fault *fault =
874 buffer->fault[fi++];
875
876 nouveau_svm_fault_cancel_fault(svm, fault);
877 }
878 } else
879 replay++;
880 }
881
882 /* Issue fault replay to the GPU. */
883 if (replay)
884 nouveau_svm_fault_replay(svm);
885 }
886
887 static int
nouveau_svm_event(struct nvif_event * event,void * argv,u32 argc)888 nouveau_svm_event(struct nvif_event *event, void *argv, u32 argc)
889 {
890 struct nouveau_svm_fault_buffer *buffer = container_of(event, typeof(*buffer), notify);
891
892 schedule_work(&buffer->work);
893 return NVIF_EVENT_KEEP;
894 }
895
896 static struct nouveau_pfnmap_args *
nouveau_pfns_to_args(void * pfns)897 nouveau_pfns_to_args(void *pfns)
898 {
899 return container_of(pfns, struct nouveau_pfnmap_args, p.phys);
900 }
901
902 u64 *
nouveau_pfns_alloc(unsigned long npages)903 nouveau_pfns_alloc(unsigned long npages)
904 {
905 struct nouveau_pfnmap_args *args;
906
907 args = kzalloc(struct_size(args, p.phys, npages), GFP_KERNEL);
908 if (!args)
909 return NULL;
910
911 args->i.type = NVIF_IOCTL_V0_MTHD;
912 args->m.method = NVIF_VMM_V0_PFNMAP;
913 args->p.page = PAGE_SHIFT;
914
915 return args->p.phys;
916 }
917
918 void
nouveau_pfns_free(u64 * pfns)919 nouveau_pfns_free(u64 *pfns)
920 {
921 struct nouveau_pfnmap_args *args = nouveau_pfns_to_args(pfns);
922
923 kfree(args);
924 }
925
926 void
nouveau_pfns_map(struct nouveau_svmm * svmm,struct mm_struct * mm,unsigned long addr,u64 * pfns,unsigned long npages)927 nouveau_pfns_map(struct nouveau_svmm *svmm, struct mm_struct *mm,
928 unsigned long addr, u64 *pfns, unsigned long npages)
929 {
930 struct nouveau_pfnmap_args *args = nouveau_pfns_to_args(pfns);
931
932 args->p.addr = addr;
933 args->p.size = npages << PAGE_SHIFT;
934
935 mutex_lock(&svmm->mutex);
936
937 nvif_object_ioctl(&svmm->vmm->vmm.object, args,
938 struct_size(args, p.phys, npages), NULL);
939
940 mutex_unlock(&svmm->mutex);
941 }
942
943 static void
nouveau_svm_fault_buffer_fini(struct nouveau_svm * svm,int id)944 nouveau_svm_fault_buffer_fini(struct nouveau_svm *svm, int id)
945 {
946 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
947
948 nvif_event_block(&buffer->notify);
949 flush_work(&buffer->work);
950 }
951
952 static int
nouveau_svm_fault_buffer_init(struct nouveau_svm * svm,int id)953 nouveau_svm_fault_buffer_init(struct nouveau_svm *svm, int id)
954 {
955 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
956 struct nvif_object *device = &svm->drm->client.device.object;
957
958 buffer->get = nvif_rd32(device, buffer->getaddr);
959 buffer->put = nvif_rd32(device, buffer->putaddr);
960 SVM_DBG(svm, "get %08x put %08x (init)", buffer->get, buffer->put);
961
962 return nvif_event_allow(&buffer->notify);
963 }
964
965 static void
nouveau_svm_fault_buffer_dtor(struct nouveau_svm * svm,int id)966 nouveau_svm_fault_buffer_dtor(struct nouveau_svm *svm, int id)
967 {
968 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
969 int i;
970
971 if (!nvif_object_constructed(&buffer->object))
972 return;
973
974 nouveau_svm_fault_buffer_fini(svm, id);
975
976 if (buffer->fault) {
977 for (i = 0; buffer->fault[i] && i < buffer->entries; i++)
978 kfree(buffer->fault[i]);
979 kvfree(buffer->fault);
980 }
981
982 nvif_event_dtor(&buffer->notify);
983 nvif_object_dtor(&buffer->object);
984 }
985
986 static int
nouveau_svm_fault_buffer_ctor(struct nouveau_svm * svm,s32 oclass,int id)987 nouveau_svm_fault_buffer_ctor(struct nouveau_svm *svm, s32 oclass, int id)
988 {
989 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
990 struct nouveau_drm *drm = svm->drm;
991 struct nvif_object *device = &drm->client.device.object;
992 struct nvif_clb069_v0 args = {};
993 int ret;
994
995 buffer->id = id;
996
997 ret = nvif_object_ctor(device, "svmFaultBuffer", 0, oclass, &args,
998 sizeof(args), &buffer->object);
999 if (ret < 0) {
1000 SVM_ERR(svm, "Fault buffer allocation failed: %d", ret);
1001 return ret;
1002 }
1003
1004 nvif_object_map(&buffer->object, NULL, 0);
1005 buffer->entries = args.entries;
1006 buffer->getaddr = args.get;
1007 buffer->putaddr = args.put;
1008 INIT_WORK(&buffer->work, nouveau_svm_fault);
1009
1010 ret = nvif_event_ctor(&buffer->object, "svmFault", id, nouveau_svm_event, true, NULL, 0,
1011 &buffer->notify);
1012 if (ret)
1013 return ret;
1014
1015 buffer->fault = kvcalloc(buffer->entries, sizeof(*buffer->fault), GFP_KERNEL);
1016 if (!buffer->fault)
1017 return -ENOMEM;
1018
1019 return nouveau_svm_fault_buffer_init(svm, id);
1020 }
1021
1022 void
nouveau_svm_resume(struct nouveau_drm * drm)1023 nouveau_svm_resume(struct nouveau_drm *drm)
1024 {
1025 struct nouveau_svm *svm = drm->svm;
1026 if (svm)
1027 nouveau_svm_fault_buffer_init(svm, 0);
1028 }
1029
1030 void
nouveau_svm_suspend(struct nouveau_drm * drm)1031 nouveau_svm_suspend(struct nouveau_drm *drm)
1032 {
1033 struct nouveau_svm *svm = drm->svm;
1034 if (svm)
1035 nouveau_svm_fault_buffer_fini(svm, 0);
1036 }
1037
1038 void
nouveau_svm_fini(struct nouveau_drm * drm)1039 nouveau_svm_fini(struct nouveau_drm *drm)
1040 {
1041 struct nouveau_svm *svm = drm->svm;
1042 if (svm) {
1043 nouveau_svm_fault_buffer_dtor(svm, 0);
1044 kfree(drm->svm);
1045 drm->svm = NULL;
1046 }
1047 }
1048
1049 void
nouveau_svm_init(struct nouveau_drm * drm)1050 nouveau_svm_init(struct nouveau_drm *drm)
1051 {
1052 static const struct nvif_mclass buffers[] = {
1053 { VOLTA_FAULT_BUFFER_A, 0 },
1054 { MAXWELL_FAULT_BUFFER_A, 0 },
1055 {}
1056 };
1057 struct nouveau_svm *svm;
1058 int ret;
1059
1060 /* Disable on Volta and newer until channel recovery is fixed,
1061 * otherwise clients will have a trivial way to trash the GPU
1062 * for everyone.
1063 */
1064 if (drm->client.device.info.family > NV_DEVICE_INFO_V0_PASCAL)
1065 return;
1066
1067 drm->svm = svm = kzalloc(struct_size(drm->svm, buffer, 1), GFP_KERNEL);
1068 if (!drm->svm)
1069 return;
1070
1071 drm->svm->drm = drm;
1072 mutex_init(&drm->svm->mutex);
1073 INIT_LIST_HEAD(&drm->svm->inst);
1074
1075 ret = nvif_mclass(&drm->client.device.object, buffers);
1076 if (ret < 0) {
1077 SVM_DBG(svm, "No supported fault buffer class");
1078 nouveau_svm_fini(drm);
1079 return;
1080 }
1081
1082 ret = nouveau_svm_fault_buffer_ctor(svm, buffers[ret].oclass, 0);
1083 if (ret) {
1084 nouveau_svm_fini(drm);
1085 return;
1086 }
1087
1088 SVM_DBG(svm, "Initialised");
1089 }
1090