2 * Copyright 2014 Advanced Micro Devices, Inc.
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sub license, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
16 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
17 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
18 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
19 * USE OR OTHER DEALINGS IN THE SOFTWARE.
21 * The above copyright notice and this permission notice (including the
22 * next paragraph) shall be included in all copies or substantial portions
28 * Christian König <christian.koenig@amd.com>
34 * For coherent userptr handling registers an MMU notifier to inform the driver
35 * about updates on the page tables of a process.
37 * When somebody tries to invalidate the page tables we block the update until
38 * all operations on the pages in question are completed, then those pages are
39 * marked as accessed and also dirty if it wasn't a read only access.
41 * New command submissions using the userptrs in question are delayed until all
42 * page table invalidation are completed and we once more see a coherent process
46 #include <linux/firmware.h>
47 #include <linux/module.h>
48 #include <linux/mmu_notifier.h>
49 #include <linux/interval_tree.h>
54 #include "amdgpu_amdkfd.h"
59 * @adev: amdgpu device pointer
60 * @mm: process address space
61 * @mn: MMU notifier structure
62 * @type: type of MMU notifier
63 * @work: destruction work item
64 * @node: hash table node to find structure by adev and mn
65 * @lock: rw semaphore protecting the notifier nodes
66 * @objects: interval tree containing amdgpu_mn_nodes
67 * @read_lock: mutex for recursive locking of @lock
68 * @recursion: depth of recursion
70 * Data for each amdgpu device and process address space.
73 /* constant after initialisation */
74 struct amdgpu_device
*adev
;
76 struct mmu_notifier mn
;
77 enum amdgpu_mn_type type
;
79 /* only used on destruction */
80 struct work_struct work
;
82 /* protected by adev->mn_lock */
83 struct hlist_node node
;
85 /* objects protected by lock */
86 struct rw_semaphore lock
;
87 struct rb_root_cached objects
;
88 struct mutex read_lock
;
93 * struct amdgpu_mn_node
95 * @it: interval node defining start-last of the affected address range
96 * @bos: list of all BOs in the affected address range
98 * Manages all BOs which are affected of a certain range of address space.
100 struct amdgpu_mn_node
{
101 struct interval_tree_node it
;
102 struct list_head bos
;
106 * amdgpu_mn_destroy - destroy the MMU notifier
108 * @work: previously sheduled work item
110 * Lazy destroys the notifier from a work item
112 static void amdgpu_mn_destroy(struct work_struct
*work
)
114 struct amdgpu_mn
*amn
= container_of(work
, struct amdgpu_mn
, work
);
115 struct amdgpu_device
*adev
= amn
->adev
;
116 struct amdgpu_mn_node
*node
, *next_node
;
117 struct amdgpu_bo
*bo
, *next_bo
;
119 mutex_lock(&adev
->mn_lock
);
120 down_write(&amn
->lock
);
121 hash_del(&amn
->node
);
122 rbtree_postorder_for_each_entry_safe(node
, next_node
,
123 &amn
->objects
.rb_root
, it
.rb
) {
124 list_for_each_entry_safe(bo
, next_bo
, &node
->bos
, mn_list
) {
126 list_del_init(&bo
->mn_list
);
130 up_write(&amn
->lock
);
131 mutex_unlock(&adev
->mn_lock
);
132 mmu_notifier_unregister_no_release(&amn
->mn
, amn
->mm
);
137 * amdgpu_mn_release - callback to notify about mm destruction
140 * @mm: the mm this callback is about
142 * Shedule a work item to lazy destroy our notifier.
144 static void amdgpu_mn_release(struct mmu_notifier
*mn
,
145 struct mm_struct
*mm
)
147 struct amdgpu_mn
*amn
= container_of(mn
, struct amdgpu_mn
, mn
);
149 INIT_WORK(&amn
->work
, amdgpu_mn_destroy
);
150 schedule_work(&amn
->work
);
155 * amdgpu_mn_lock - take the write side lock for this notifier
159 void amdgpu_mn_lock(struct amdgpu_mn
*mn
)
162 down_write(&mn
->lock
);
166 * amdgpu_mn_unlock - drop the write side lock for this notifier
170 void amdgpu_mn_unlock(struct amdgpu_mn
*mn
)
177 * amdgpu_mn_read_lock - take the read side lock for this notifier
181 static int amdgpu_mn_read_lock(struct amdgpu_mn
*amn
, bool blockable
)
184 mutex_lock(&amn
->read_lock
);
185 else if (!mutex_trylock(&amn
->read_lock
))
188 if (atomic_inc_return(&amn
->recursion
) == 1)
189 down_read_non_owner(&amn
->lock
);
190 mutex_unlock(&amn
->read_lock
);
196 * amdgpu_mn_read_unlock - drop the read side lock for this notifier
200 static void amdgpu_mn_read_unlock(struct amdgpu_mn
*amn
)
202 if (atomic_dec_return(&amn
->recursion
) == 0)
203 up_read_non_owner(&amn
->lock
);
207 * amdgpu_mn_invalidate_node - unmap all BOs of a node
209 * @node: the node with the BOs to unmap
210 * @start: start of address range affected
211 * @end: end of address range affected
213 * Block for operations on BOs to finish and mark pages as accessed and
216 static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node
*node
,
220 struct amdgpu_bo
*bo
;
223 list_for_each_entry(bo
, &node
->bos
, mn_list
) {
225 if (!amdgpu_ttm_tt_affect_userptr(bo
->tbo
.ttm
, start
, end
))
228 r
= reservation_object_wait_timeout_rcu(bo
->tbo
.resv
,
229 true, false, MAX_SCHEDULE_TIMEOUT
);
231 DRM_ERROR("(%ld) failed to wait for user bo\n", r
);
233 amdgpu_ttm_tt_mark_user_pages(bo
->tbo
.ttm
);
238 * amdgpu_mn_invalidate_range_start_gfx - callback to notify about mm change
241 * @range: mmu notifier context
243 * Block for operations on BOs to finish and mark pages as accessed and
246 static int amdgpu_mn_invalidate_range_start_gfx(struct mmu_notifier
*mn
,
247 const struct mmu_notifier_range
*range
)
249 struct amdgpu_mn
*amn
= container_of(mn
, struct amdgpu_mn
, mn
);
250 struct interval_tree_node
*it
;
253 /* notification is exclusive, but interval is inclusive */
254 end
= range
->end
- 1;
256 /* TODO we should be able to split locking for interval tree and
257 * amdgpu_mn_invalidate_node
259 if (amdgpu_mn_read_lock(amn
, range
->blockable
))
262 it
= interval_tree_iter_first(&amn
->objects
, range
->start
, end
);
264 struct amdgpu_mn_node
*node
;
266 if (!range
->blockable
) {
267 amdgpu_mn_read_unlock(amn
);
271 node
= container_of(it
, struct amdgpu_mn_node
, it
);
272 it
= interval_tree_iter_next(it
, range
->start
, end
);
274 amdgpu_mn_invalidate_node(node
, range
->start
, end
);
281 * amdgpu_mn_invalidate_range_start_hsa - callback to notify about mm change
284 * @mm: the mm this callback is about
285 * @start: start of updated range
286 * @end: end of updated range
288 * We temporarily evict all BOs between start and end. This
289 * necessitates evicting all user-mode queues of the process. The BOs
290 * are restorted in amdgpu_mn_invalidate_range_end_hsa.
292 static int amdgpu_mn_invalidate_range_start_hsa(struct mmu_notifier
*mn
,
293 const struct mmu_notifier_range
*range
)
295 struct amdgpu_mn
*amn
= container_of(mn
, struct amdgpu_mn
, mn
);
296 struct interval_tree_node
*it
;
299 /* notification is exclusive, but interval is inclusive */
300 end
= range
->end
- 1;
302 if (amdgpu_mn_read_lock(amn
, range
->blockable
))
305 it
= interval_tree_iter_first(&amn
->objects
, range
->start
, end
);
307 struct amdgpu_mn_node
*node
;
308 struct amdgpu_bo
*bo
;
310 if (!range
->blockable
) {
311 amdgpu_mn_read_unlock(amn
);
315 node
= container_of(it
, struct amdgpu_mn_node
, it
);
316 it
= interval_tree_iter_next(it
, range
->start
, end
);
318 list_for_each_entry(bo
, &node
->bos
, mn_list
) {
319 struct kgd_mem
*mem
= bo
->kfd_bo
;
321 if (amdgpu_ttm_tt_affect_userptr(bo
->tbo
.ttm
,
324 amdgpu_amdkfd_evict_userptr(mem
, range
->mm
);
332 * amdgpu_mn_invalidate_range_end - callback to notify about mm change
335 * @mm: the mm this callback is about
336 * @start: start of updated range
337 * @end: end of updated range
339 * Release the lock again to allow new command submissions.
341 static void amdgpu_mn_invalidate_range_end(struct mmu_notifier
*mn
,
342 const struct mmu_notifier_range
*range
)
344 struct amdgpu_mn
*amn
= container_of(mn
, struct amdgpu_mn
, mn
);
346 amdgpu_mn_read_unlock(amn
);
349 static const struct mmu_notifier_ops amdgpu_mn_ops
[] = {
350 [AMDGPU_MN_TYPE_GFX
] = {
351 .release
= amdgpu_mn_release
,
352 .invalidate_range_start
= amdgpu_mn_invalidate_range_start_gfx
,
353 .invalidate_range_end
= amdgpu_mn_invalidate_range_end
,
355 [AMDGPU_MN_TYPE_HSA
] = {
356 .release
= amdgpu_mn_release
,
357 .invalidate_range_start
= amdgpu_mn_invalidate_range_start_hsa
,
358 .invalidate_range_end
= amdgpu_mn_invalidate_range_end
,
362 /* Low bits of any reasonable mm pointer will be unused due to struct
363 * alignment. Use these bits to make a unique key from the mm pointer
366 #define AMDGPU_MN_KEY(mm, type) ((unsigned long)(mm) + (type))
369 * amdgpu_mn_get - create notifier context
371 * @adev: amdgpu device pointer
372 * @type: type of MMU notifier context
374 * Creates a notifier context for current->mm.
376 struct amdgpu_mn
*amdgpu_mn_get(struct amdgpu_device
*adev
,
377 enum amdgpu_mn_type type
)
379 struct mm_struct
*mm
= current
->mm
;
380 struct amdgpu_mn
*amn
;
381 unsigned long key
= AMDGPU_MN_KEY(mm
, type
);
384 mutex_lock(&adev
->mn_lock
);
385 if (down_write_killable(&mm
->mmap_sem
)) {
386 mutex_unlock(&adev
->mn_lock
);
387 return ERR_PTR(-EINTR
);
390 hash_for_each_possible(adev
->mn_hash
, amn
, node
, key
)
391 if (AMDGPU_MN_KEY(amn
->mm
, amn
->type
) == key
)
394 amn
= kzalloc(sizeof(*amn
), GFP_KERNEL
);
396 amn
= ERR_PTR(-ENOMEM
);
402 init_rwsem(&amn
->lock
);
404 amn
->mn
.ops
= &amdgpu_mn_ops
[type
];
405 amn
->objects
= RB_ROOT_CACHED
;
406 mutex_init(&amn
->read_lock
);
407 atomic_set(&amn
->recursion
, 0);
409 r
= __mmu_notifier_register(&amn
->mn
, mm
);
413 hash_add(adev
->mn_hash
, &amn
->node
, AMDGPU_MN_KEY(mm
, type
));
416 up_write(&mm
->mmap_sem
);
417 mutex_unlock(&adev
->mn_lock
);
422 up_write(&mm
->mmap_sem
);
423 mutex_unlock(&adev
->mn_lock
);
430 * amdgpu_mn_register - register a BO for notifier updates
432 * @bo: amdgpu buffer object
433 * @addr: userptr addr we should monitor
435 * Registers an MMU notifier for the given BO at the specified address.
436 * Returns 0 on success, -ERRNO if anything goes wrong.
438 int amdgpu_mn_register(struct amdgpu_bo
*bo
, unsigned long addr
)
440 unsigned long end
= addr
+ amdgpu_bo_size(bo
) - 1;
441 struct amdgpu_device
*adev
= amdgpu_ttm_adev(bo
->tbo
.bdev
);
442 enum amdgpu_mn_type type
=
443 bo
->kfd_bo
? AMDGPU_MN_TYPE_HSA
: AMDGPU_MN_TYPE_GFX
;
444 struct amdgpu_mn
*amn
;
445 struct amdgpu_mn_node
*node
= NULL
, *new_node
;
446 struct list_head bos
;
447 struct interval_tree_node
*it
;
449 amn
= amdgpu_mn_get(adev
, type
);
453 new_node
= kmalloc(sizeof(*new_node
), GFP_KERNEL
);
457 INIT_LIST_HEAD(&bos
);
459 down_write(&amn
->lock
);
461 while ((it
= interval_tree_iter_first(&amn
->objects
, addr
, end
))) {
463 node
= container_of(it
, struct amdgpu_mn_node
, it
);
464 interval_tree_remove(&node
->it
, &amn
->objects
);
465 addr
= min(it
->start
, addr
);
466 end
= max(it
->last
, end
);
467 list_splice(&node
->bos
, &bos
);
477 node
->it
.start
= addr
;
479 INIT_LIST_HEAD(&node
->bos
);
480 list_splice(&bos
, &node
->bos
);
481 list_add(&bo
->mn_list
, &node
->bos
);
483 interval_tree_insert(&node
->it
, &amn
->objects
);
485 up_write(&amn
->lock
);
491 * amdgpu_mn_unregister - unregister a BO for notifier updates
493 * @bo: amdgpu buffer object
495 * Remove any registration of MMU notifier updates from the buffer object.
497 void amdgpu_mn_unregister(struct amdgpu_bo
*bo
)
499 struct amdgpu_device
*adev
= amdgpu_ttm_adev(bo
->tbo
.bdev
);
500 struct amdgpu_mn
*amn
;
501 struct list_head
*head
;
503 mutex_lock(&adev
->mn_lock
);
507 mutex_unlock(&adev
->mn_lock
);
511 down_write(&amn
->lock
);
513 /* save the next list entry for later */
514 head
= bo
->mn_list
.next
;
517 list_del_init(&bo
->mn_list
);
519 if (list_empty(head
)) {
520 struct amdgpu_mn_node
*node
;
522 node
= container_of(head
, struct amdgpu_mn_node
, bos
);
523 interval_tree_remove(&node
->it
, &amn
->objects
);
527 up_write(&amn
->lock
);
528 mutex_unlock(&adev
->mn_lock
);