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
41struct 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
81struct 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
87struct nouveau_ivmm {
88 struct nouveau_svmm *svmm;
89 u64 inst;
90 struct list_head head;
91};
92
93static struct nouveau_ivmm *
94nouveau_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
109int
110nouveau_svmm_bind(struct drm_device *dev, void *data,
111 struct drm_file *file_priv)
112{
113 struct nouveau_cli *cli = nouveau_cli(fpriv: 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, start_addr: addr, end_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(drm: cli->drm, svmm: cli->svm.svmm, vma, start: addr,
187 end: 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. */
205void
206nouveau_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(svm: svmm->vmm->cli->drm->svm, inst);
212 if (ivmm) {
213 list_del(entry: &ivmm->head);
214 kfree(objp: ivmm);
215 }
216 mutex_unlock(lock: &svmm->vmm->cli->drm->svm->mutex);
217 }
218}
219
220/* Link channel instance to SVMM. */
221int
222nouveau_svmm_join(struct nouveau_svmm *svmm, u64 inst)
223{
224 struct nouveau_ivmm *ivmm;
225 if (svmm) {
226 if (!(ivmm = kmalloc(size: 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(new: &ivmm->head, head: &svmm->vmm->cli->drm->svm->inst);
233 mutex_unlock(lock: &svmm->vmm->cli->drm->svm->mutex);
234 }
235 return 0;
236}
237
238/* Invalidate SVMM address-range on GPU. */
239void
240nouveau_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
251static int
252nouveau_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(range: 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 limit: svmm->unmanaged.limit);
281 }
282 start = svmm->unmanaged.limit;
283 }
284
285 nouveau_svmm_invalidate(svmm, start, limit);
286
287out:
288 mutex_unlock(lock: &svmm->mutex);
289 return 0;
290}
291
292static void nouveau_svmm_free_notifier(struct mmu_notifier *mn)
293{
294 kfree(container_of(mn, struct nouveau_svmm, notifier));
295}
296
297static 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
302void
303nouveau_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(lock: &svmm->mutex);
310 mmu_notifier_put(subscription: &svmm->notifier);
311 *psvmm = NULL;
312 }
313}
314
315int
316nouveau_svmm_init(struct drm_device *dev, void *data,
317 struct drm_file *file_priv)
318{
319 struct nouveau_cli *cli = nouveau_cli(fpriv: 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(size: 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(subscription: &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(lock: &cli->mutex);
369 return 0;
370
371out_mm_unlock:
372 mmap_write_unlock(current->mm);
373out_free:
374 mutex_unlock(lock: &cli->mutex);
375 kfree(objp: svmm);
376 return ret;
377}
378
379/* Issue fault replay for GPU to retry accesses that faulted previously. */
380static void
381nouveau_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 */
395static void
396nouveau_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
410static void
411nouveau_svm_fault_cancel_fault(struct nouveau_svm *svm,
412 struct nouveau_svm_fault *fault)
413{
414 nouveau_svm_fault_cancel(svm, inst: fault->inst,
415 hub: fault->hub,
416 gpc: fault->gpc,
417 client: fault->client);
418}
419
420static int
421nouveau_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
438static int
439nouveau_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(fault: fa->access) -
449 nouveau_svm_fault_priority(fault: fb->access);
450}
451
452static void
453nouveau_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(size: 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
501struct svm_notifier {
502 struct mmu_interval_notifier notifier;
503 struct nouveau_svmm *svmm;
504};
505
506static 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(lock: &sn->svmm->mutex))
527 return false;
528 mmu_interval_set_seq(interval_sub: mni, cur_seq);
529 mutex_unlock(lock: &sn->svmm->mutex);
530 return true;
531}
532
533static const struct mmu_interval_notifier_ops nouveau_svm_mni_ops = {
534 .invalidate = nouveau_svm_range_invalidate,
535};
536
537static 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(hmm_pfn: 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(hmm_pfn: range->hmm_pfns[0])) {
565 unsigned long addr = args->p.addr;
566
567 args->p.page = hmm_pfn_to_map_order(hmm_pfn: 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
585static 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 page *page;
594 unsigned long start = args->p.addr;
595 unsigned long notifier_seq;
596 int ret = 0;
597
598 ret = mmu_interval_notifier_insert(interval_sub: &notifier->notifier, mm,
599 start: args->p.addr, length: args->p.size,
600 ops: &nouveau_svm_mni_ops);
601 if (ret)
602 return ret;
603
604 while (true) {
605 if (time_after(jiffies, timeout)) {
606 ret = -EBUSY;
607 goto out;
608 }
609
610 notifier_seq = mmu_interval_read_begin(interval_sub: &notifier->notifier);
611 mmap_read_lock(mm);
612 ret = make_device_exclusive_range(mm, start, end: start + PAGE_SIZE,
613 pages: &page, arg: drm->dev);
614 mmap_read_unlock(mm);
615 if (ret <= 0 || !page) {
616 ret = -EINVAL;
617 goto out;
618 }
619
620 mutex_lock(&svmm->mutex);
621 if (!mmu_interval_read_retry(interval_sub: &notifier->notifier,
622 seq: notifier_seq))
623 break;
624 mutex_unlock(lock: &svmm->mutex);
625 }
626
627 /* Map the page on the GPU. */
628 args->p.page = 12;
629 args->p.size = PAGE_SIZE;
630 args->p.addr = start;
631 args->p.phys[0] = page_to_phys(page) |
632 NVIF_VMM_PFNMAP_V0_V |
633 NVIF_VMM_PFNMAP_V0_W |
634 NVIF_VMM_PFNMAP_V0_A |
635 NVIF_VMM_PFNMAP_V0_HOST;
636
637 ret = nvif_object_ioctl(&svmm->vmm->vmm.object, args, size, NULL);
638 mutex_unlock(lock: &svmm->mutex);
639
640 unlock_page(page);
641 put_page(page);
642
643out:
644 mmu_interval_notifier_remove(interval_sub: &notifier->notifier);
645 return ret;
646}
647
648static int nouveau_range_fault(struct nouveau_svmm *svmm,
649 struct nouveau_drm *drm,
650 struct nouveau_pfnmap_args *args, u32 size,
651 unsigned long hmm_flags,
652 struct svm_notifier *notifier)
653{
654 unsigned long timeout =
655 jiffies + msecs_to_jiffies(HMM_RANGE_DEFAULT_TIMEOUT);
656 /* Have HMM fault pages within the fault window to the GPU. */
657 unsigned long hmm_pfns[1];
658 struct hmm_range range = {
659 .notifier = &notifier->notifier,
660 .default_flags = hmm_flags,
661 .hmm_pfns = hmm_pfns,
662 .dev_private_owner = drm->dev,
663 };
664 struct mm_struct *mm = svmm->notifier.mm;
665 int ret;
666
667 ret = mmu_interval_notifier_insert(interval_sub: &notifier->notifier, mm,
668 start: args->p.addr, length: args->p.size,
669 ops: &nouveau_svm_mni_ops);
670 if (ret)
671 return ret;
672
673 range.start = notifier->notifier.interval_tree.start;
674 range.end = notifier->notifier.interval_tree.last + 1;
675
676 while (true) {
677 if (time_after(jiffies, timeout)) {
678 ret = -EBUSY;
679 goto out;
680 }
681
682 range.notifier_seq = mmu_interval_read_begin(interval_sub: range.notifier);
683 mmap_read_lock(mm);
684 ret = hmm_range_fault(range: &range);
685 mmap_read_unlock(mm);
686 if (ret) {
687 if (ret == -EBUSY)
688 continue;
689 goto out;
690 }
691
692 mutex_lock(&svmm->mutex);
693 if (mmu_interval_read_retry(interval_sub: range.notifier,
694 seq: range.notifier_seq)) {
695 mutex_unlock(lock: &svmm->mutex);
696 continue;
697 }
698 break;
699 }
700
701 nouveau_hmm_convert_pfn(drm, range: &range, args);
702
703 ret = nvif_object_ioctl(&svmm->vmm->vmm.object, args, size, NULL);
704 mutex_unlock(lock: &svmm->mutex);
705
706out:
707 mmu_interval_notifier_remove(interval_sub: &notifier->notifier);
708
709 return ret;
710}
711
712static void
713nouveau_svm_fault(struct work_struct *work)
714{
715 struct nouveau_svm_fault_buffer *buffer = container_of(work, typeof(*buffer), work);
716 struct nouveau_svm *svm = container_of(buffer, typeof(*svm), buffer[buffer->id]);
717 struct nvif_object *device = &svm->drm->client.device.object;
718 struct nouveau_svmm *svmm;
719 struct {
720 struct nouveau_pfnmap_args i;
721 u64 phys[1];
722 } args;
723 unsigned long hmm_flags;
724 u64 inst, start, limit;
725 int fi, fn;
726 int replay = 0, atomic = 0, ret;
727
728 /* Parse available fault buffer entries into a cache, and update
729 * the GET pointer so HW can reuse the entries.
730 */
731 SVM_DBG(svm, "fault handler");
732 if (buffer->get == buffer->put) {
733 buffer->put = nvif_rd32(device, buffer->putaddr);
734 buffer->get = nvif_rd32(device, buffer->getaddr);
735 if (buffer->get == buffer->put)
736 return;
737 }
738 buffer->fault_nr = 0;
739
740 SVM_DBG(svm, "get %08x put %08x", buffer->get, buffer->put);
741 while (buffer->get != buffer->put) {
742 nouveau_svm_fault_cache(svm, buffer, offset: buffer->get * 0x20);
743 if (++buffer->get == buffer->entries)
744 buffer->get = 0;
745 }
746 nvif_wr32(device, buffer->getaddr, buffer->get);
747 SVM_DBG(svm, "%d fault(s) pending", buffer->fault_nr);
748
749 /* Sort parsed faults by instance pointer to prevent unnecessary
750 * instance to SVMM translations, followed by address and access
751 * type to reduce the amount of work when handling the faults.
752 */
753 sort(base: buffer->fault, num: buffer->fault_nr, size: sizeof(*buffer->fault),
754 cmp_func: nouveau_svm_fault_cmp, NULL);
755
756 /* Lookup SVMM structure for each unique instance pointer. */
757 mutex_lock(&svm->mutex);
758 for (fi = 0, svmm = NULL; fi < buffer->fault_nr; fi++) {
759 if (!svmm || buffer->fault[fi]->inst != inst) {
760 struct nouveau_ivmm *ivmm =
761 nouveau_ivmm_find(svm, inst: buffer->fault[fi]->inst);
762 svmm = ivmm ? ivmm->svmm : NULL;
763 inst = buffer->fault[fi]->inst;
764 SVM_DBG(svm, "inst %016llx -> svm-%p", inst, svmm);
765 }
766 buffer->fault[fi]->svmm = svmm;
767 }
768 mutex_unlock(lock: &svm->mutex);
769
770 /* Process list of faults. */
771 args.i.i.version = 0;
772 args.i.i.type = NVIF_IOCTL_V0_MTHD;
773 args.i.m.version = 0;
774 args.i.m.method = NVIF_VMM_V0_PFNMAP;
775 args.i.p.version = 0;
776
777 for (fi = 0; fn = fi + 1, fi < buffer->fault_nr; fi = fn) {
778 struct svm_notifier notifier;
779 struct mm_struct *mm;
780
781 /* Cancel any faults from non-SVM channels. */
782 if (!(svmm = buffer->fault[fi]->svmm)) {
783 nouveau_svm_fault_cancel_fault(svm, fault: buffer->fault[fi]);
784 continue;
785 }
786 SVMM_DBG(svmm, "addr %016llx", buffer->fault[fi]->addr);
787
788 /* We try and group handling of faults within a small
789 * window into a single update.
790 */
791 start = buffer->fault[fi]->addr;
792 limit = start + PAGE_SIZE;
793 if (start < svmm->unmanaged.limit)
794 limit = min_t(u64, limit, svmm->unmanaged.start);
795
796 /*
797 * Prepare the GPU-side update of all pages within the
798 * fault window, determining required pages and access
799 * permissions based on pending faults.
800 */
801 args.i.p.addr = start;
802 args.i.p.page = PAGE_SHIFT;
803 args.i.p.size = PAGE_SIZE;
804 /*
805 * Determine required permissions based on GPU fault
806 * access flags.
807 */
808 switch (buffer->fault[fi]->access) {
809 case 0: /* READ. */
810 hmm_flags = HMM_PFN_REQ_FAULT;
811 break;
812 case 2: /* ATOMIC. */
813 atomic = true;
814 break;
815 case 3: /* PREFETCH. */
816 hmm_flags = 0;
817 break;
818 default:
819 hmm_flags = HMM_PFN_REQ_FAULT | HMM_PFN_REQ_WRITE;
820 break;
821 }
822
823 mm = svmm->notifier.mm;
824 if (!mmget_not_zero(mm)) {
825 nouveau_svm_fault_cancel_fault(svm, fault: buffer->fault[fi]);
826 continue;
827 }
828
829 notifier.svmm = svmm;
830 if (atomic)
831 ret = nouveau_atomic_range_fault(svmm, drm: svm->drm,
832 args: &args.i, size: sizeof(args),
833 notifier: &notifier);
834 else
835 ret = nouveau_range_fault(svmm, drm: svm->drm, args: &args.i,
836 size: sizeof(args), hmm_flags,
837 notifier: &notifier);
838 mmput(mm);
839
840 limit = args.i.p.addr + args.i.p.size;
841 for (fn = fi; ++fn < buffer->fault_nr; ) {
842 /* It's okay to skip over duplicate addresses from the
843 * same SVMM as faults are ordered by access type such
844 * that only the first one needs to be handled.
845 *
846 * ie. WRITE faults appear first, thus any handling of
847 * pending READ faults will already be satisfied.
848 * But if a large page is mapped, make sure subsequent
849 * fault addresses have sufficient access permission.
850 */
851 if (buffer->fault[fn]->svmm != svmm ||
852 buffer->fault[fn]->addr >= limit ||
853 (buffer->fault[fi]->access == FAULT_ACCESS_READ &&
854 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_V)) ||
855 (buffer->fault[fi]->access != FAULT_ACCESS_READ &&
856 buffer->fault[fi]->access != FAULT_ACCESS_PREFETCH &&
857 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_W)) ||
858 (buffer->fault[fi]->access != FAULT_ACCESS_READ &&
859 buffer->fault[fi]->access != FAULT_ACCESS_WRITE &&
860 buffer->fault[fi]->access != FAULT_ACCESS_PREFETCH &&
861 !(args.phys[0] & NVIF_VMM_PFNMAP_V0_A)))
862 break;
863 }
864
865 /* If handling failed completely, cancel all faults. */
866 if (ret) {
867 while (fi < fn) {
868 struct nouveau_svm_fault *fault =
869 buffer->fault[fi++];
870
871 nouveau_svm_fault_cancel_fault(svm, fault);
872 }
873 } else
874 replay++;
875 }
876
877 /* Issue fault replay to the GPU. */
878 if (replay)
879 nouveau_svm_fault_replay(svm);
880}
881
882static int
883nouveau_svm_event(struct nvif_event *event, void *argv, u32 argc)
884{
885 struct nouveau_svm_fault_buffer *buffer = container_of(event, typeof(*buffer), notify);
886
887 schedule_work(work: &buffer->work);
888 return NVIF_EVENT_KEEP;
889}
890
891static struct nouveau_pfnmap_args *
892nouveau_pfns_to_args(void *pfns)
893{
894 return container_of(pfns, struct nouveau_pfnmap_args, p.phys);
895}
896
897u64 *
898nouveau_pfns_alloc(unsigned long npages)
899{
900 struct nouveau_pfnmap_args *args;
901
902 args = kzalloc(struct_size(args, p.phys, npages), GFP_KERNEL);
903 if (!args)
904 return NULL;
905
906 args->i.type = NVIF_IOCTL_V0_MTHD;
907 args->m.method = NVIF_VMM_V0_PFNMAP;
908 args->p.page = PAGE_SHIFT;
909
910 return args->p.phys;
911}
912
913void
914nouveau_pfns_free(u64 *pfns)
915{
916 struct nouveau_pfnmap_args *args = nouveau_pfns_to_args(pfns);
917
918 kfree(objp: args);
919}
920
921void
922nouveau_pfns_map(struct nouveau_svmm *svmm, struct mm_struct *mm,
923 unsigned long addr, u64 *pfns, unsigned long npages)
924{
925 struct nouveau_pfnmap_args *args = nouveau_pfns_to_args(pfns);
926
927 args->p.addr = addr;
928 args->p.size = npages << PAGE_SHIFT;
929
930 mutex_lock(&svmm->mutex);
931
932 nvif_object_ioctl(&svmm->vmm->vmm.object, args,
933 struct_size(args, p.phys, npages), NULL);
934
935 mutex_unlock(lock: &svmm->mutex);
936}
937
938static void
939nouveau_svm_fault_buffer_fini(struct nouveau_svm *svm, int id)
940{
941 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
942
943 nvif_event_block(&buffer->notify);
944 flush_work(work: &buffer->work);
945}
946
947static int
948nouveau_svm_fault_buffer_init(struct nouveau_svm *svm, int id)
949{
950 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
951 struct nvif_object *device = &svm->drm->client.device.object;
952
953 buffer->get = nvif_rd32(device, buffer->getaddr);
954 buffer->put = nvif_rd32(device, buffer->putaddr);
955 SVM_DBG(svm, "get %08x put %08x (init)", buffer->get, buffer->put);
956
957 return nvif_event_allow(&buffer->notify);
958}
959
960static void
961nouveau_svm_fault_buffer_dtor(struct nouveau_svm *svm, int id)
962{
963 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
964 int i;
965
966 if (!nvif_object_constructed(&buffer->object))
967 return;
968
969 nouveau_svm_fault_buffer_fini(svm, id);
970
971 if (buffer->fault) {
972 for (i = 0; buffer->fault[i] && i < buffer->entries; i++)
973 kfree(objp: buffer->fault[i]);
974 kvfree(addr: buffer->fault);
975 }
976
977 nvif_event_dtor(&buffer->notify);
978 nvif_object_dtor(&buffer->object);
979}
980
981static int
982nouveau_svm_fault_buffer_ctor(struct nouveau_svm *svm, s32 oclass, int id)
983{
984 struct nouveau_svm_fault_buffer *buffer = &svm->buffer[id];
985 struct nouveau_drm *drm = svm->drm;
986 struct nvif_object *device = &drm->client.device.object;
987 struct nvif_clb069_v0 args = {};
988 int ret;
989
990 buffer->id = id;
991
992 ret = nvif_object_ctor(device, "svmFaultBuffer", 0, oclass, &args,
993 sizeof(args), &buffer->object);
994 if (ret < 0) {
995 SVM_ERR(svm, "Fault buffer allocation failed: %d", ret);
996 return ret;
997 }
998
999 nvif_object_map(&buffer->object, NULL, 0);
1000 buffer->entries = args.entries;
1001 buffer->getaddr = args.get;
1002 buffer->putaddr = args.put;
1003 INIT_WORK(&buffer->work, nouveau_svm_fault);
1004
1005 ret = nvif_event_ctor(&buffer->object, "svmFault", id, nouveau_svm_event, true, NULL, 0,
1006 &buffer->notify);
1007 if (ret)
1008 return ret;
1009
1010 buffer->fault = kvcalloc(n: buffer->entries, size: sizeof(*buffer->fault), GFP_KERNEL);
1011 if (!buffer->fault)
1012 return -ENOMEM;
1013
1014 return nouveau_svm_fault_buffer_init(svm, id);
1015}
1016
1017void
1018nouveau_svm_resume(struct nouveau_drm *drm)
1019{
1020 struct nouveau_svm *svm = drm->svm;
1021 if (svm)
1022 nouveau_svm_fault_buffer_init(svm, id: 0);
1023}
1024
1025void
1026nouveau_svm_suspend(struct nouveau_drm *drm)
1027{
1028 struct nouveau_svm *svm = drm->svm;
1029 if (svm)
1030 nouveau_svm_fault_buffer_fini(svm, id: 0);
1031}
1032
1033void
1034nouveau_svm_fini(struct nouveau_drm *drm)
1035{
1036 struct nouveau_svm *svm = drm->svm;
1037 if (svm) {
1038 nouveau_svm_fault_buffer_dtor(svm, id: 0);
1039 kfree(objp: drm->svm);
1040 drm->svm = NULL;
1041 }
1042}
1043
1044void
1045nouveau_svm_init(struct nouveau_drm *drm)
1046{
1047 static const struct nvif_mclass buffers[] = {
1048 { VOLTA_FAULT_BUFFER_A, 0 },
1049 { MAXWELL_FAULT_BUFFER_A, 0 },
1050 {}
1051 };
1052 struct nouveau_svm *svm;
1053 int ret;
1054
1055 /* Disable on Volta and newer until channel recovery is fixed,
1056 * otherwise clients will have a trivial way to trash the GPU
1057 * for everyone.
1058 */
1059 if (drm->client.device.info.family > NV_DEVICE_INFO_V0_PASCAL)
1060 return;
1061
1062 drm->svm = svm = kzalloc(struct_size(drm->svm, buffer, 1), GFP_KERNEL);
1063 if (!drm->svm)
1064 return;
1065
1066 drm->svm->drm = drm;
1067 mutex_init(&drm->svm->mutex);
1068 INIT_LIST_HEAD(list: &drm->svm->inst);
1069
1070 ret = nvif_mclass(&drm->client.device.object, buffers);
1071 if (ret < 0) {
1072 SVM_DBG(svm, "No supported fault buffer class");
1073 nouveau_svm_fini(drm);
1074 return;
1075 }
1076
1077 ret = nouveau_svm_fault_buffer_ctor(svm, oclass: buffers[ret].oclass, id: 0);
1078 if (ret) {
1079 nouveau_svm_fini(drm);
1080 return;
1081 }
1082
1083 SVM_DBG(svm, "Initialised");
1084}
1085

source code of linux/drivers/gpu/drm/nouveau/nouveau_svm.c