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

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