1 /*
2 * Copyright 2014 Advanced Micro Devices, Inc.
3 * All Rights Reserved.
4 *
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:
12 *
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.
20 *
21 * The above copyright notice and this permission notice (including the
22 * next paragraph) shall be included in all copies or substantial portions
23 * of the Software.
24 *
25 */
26 /*
27 * Authors:
28 * Christian König <christian.koenig@amd.com>
29 */
30
31 #include <linux/firmware.h>
32 #include <linux/module.h>
33 #include <linux/mmu_notifier.h>
34 #include <drm/drmP.h>
35 #include <drm/drm.h>
36
37 #include "amdgpu.h"
38
39 struct amdgpu_mn {
40 /* constant after initialisation */
41 struct amdgpu_device *adev;
42 struct mm_struct *mm;
43 struct mmu_notifier mn;
44
45 /* only used on destruction */
46 struct work_struct work;
47
48 /* protected by adev->mn_lock */
49 struct hlist_node node;
50
51 /* objects protected by lock */
52 struct mutex lock;
53 struct rb_root objects;
54 };
55
56 struct amdgpu_mn_node {
57 struct interval_tree_node it;
58 struct list_head bos;
59 };
60
61 /**
62 * amdgpu_mn_destroy - destroy the rmn
63 *
64 * @work: previously sheduled work item
65 *
66 * Lazy destroys the notifier from a work item
67 */
amdgpu_mn_destroy(struct work_struct * work)68 static void amdgpu_mn_destroy(struct work_struct *work)
69 {
70 struct amdgpu_mn *rmn = container_of(work, struct amdgpu_mn, work);
71 struct amdgpu_device *adev = rmn->adev;
72 struct amdgpu_mn_node *node, *next_node;
73 struct amdgpu_bo *bo, *next_bo;
74
75 mutex_lock(&adev->mn_lock);
76 mutex_lock(&rmn->lock);
77 hash_del(&rmn->node);
78 rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
79 it.rb) {
80 list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
81 bo->mn = NULL;
82 list_del_init(&bo->mn_list);
83 }
84 kfree(node);
85 }
86 mutex_unlock(&rmn->lock);
87 mutex_unlock(&adev->mn_lock);
88 mmu_notifier_unregister_no_release(&rmn->mn, rmn->mm);
89 kfree(rmn);
90 }
91
92 /**
93 * amdgpu_mn_release - callback to notify about mm destruction
94 *
95 * @mn: our notifier
96 * @mn: the mm this callback is about
97 *
98 * Shedule a work item to lazy destroy our notifier.
99 */
amdgpu_mn_release(struct mmu_notifier * mn,struct mm_struct * mm)100 static void amdgpu_mn_release(struct mmu_notifier *mn,
101 struct mm_struct *mm)
102 {
103 struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
104 INIT_WORK(&rmn->work, amdgpu_mn_destroy);
105 schedule_work(&rmn->work);
106 }
107
108 /**
109 * amdgpu_mn_invalidate_node - unmap all BOs of a node
110 *
111 * @node: the node with the BOs to unmap
112 *
113 * We block for all BOs and unmap them by move them
114 * into system domain again.
115 */
amdgpu_mn_invalidate_node(struct amdgpu_mn_node * node,unsigned long start,unsigned long end)116 static void amdgpu_mn_invalidate_node(struct amdgpu_mn_node *node,
117 unsigned long start,
118 unsigned long end)
119 {
120 struct amdgpu_bo *bo;
121 long r;
122
123 list_for_each_entry(bo, &node->bos, mn_list) {
124
125 if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start, end))
126 continue;
127
128 r = amdgpu_bo_reserve(bo, true);
129 if (r) {
130 DRM_ERROR("(%ld) failed to reserve user bo\n", r);
131 continue;
132 }
133
134 r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
135 true, false, MAX_SCHEDULE_TIMEOUT);
136 if (r <= 0)
137 DRM_ERROR("(%ld) failed to wait for user bo\n", r);
138
139 amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
140 r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
141 if (r)
142 DRM_ERROR("(%ld) failed to validate user bo\n", r);
143
144 amdgpu_bo_unreserve(bo);
145 }
146 }
147
148 /**
149 * amdgpu_mn_invalidate_page - callback to notify about mm change
150 *
151 * @mn: our notifier
152 * @mn: the mm this callback is about
153 * @address: address of invalidate page
154 *
155 * Invalidation of a single page. Blocks for all BOs mapping it
156 * and unmap them by move them into system domain again.
157 */
amdgpu_mn_invalidate_page(struct mmu_notifier * mn,struct mm_struct * mm,unsigned long address)158 static void amdgpu_mn_invalidate_page(struct mmu_notifier *mn,
159 struct mm_struct *mm,
160 unsigned long address)
161 {
162 struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
163 struct interval_tree_node *it;
164
165 mutex_lock(&rmn->lock);
166
167 it = interval_tree_iter_first(&rmn->objects, address, address);
168 if (it) {
169 struct amdgpu_mn_node *node;
170
171 node = container_of(it, struct amdgpu_mn_node, it);
172 amdgpu_mn_invalidate_node(node, address, address);
173 }
174
175 mutex_unlock(&rmn->lock);
176 }
177
178 /**
179 * amdgpu_mn_invalidate_range_start - callback to notify about mm change
180 *
181 * @mn: our notifier
182 * @mn: the mm this callback is about
183 * @start: start of updated range
184 * @end: end of updated range
185 *
186 * We block for all BOs between start and end to be idle and
187 * unmap them by move them into system domain again.
188 */
amdgpu_mn_invalidate_range_start(struct mmu_notifier * mn,struct mm_struct * mm,unsigned long start,unsigned long end)189 static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
190 struct mm_struct *mm,
191 unsigned long start,
192 unsigned long end)
193 {
194 struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
195 struct interval_tree_node *it;
196
197 /* notification is exclusive, but interval is inclusive */
198 end -= 1;
199
200 mutex_lock(&rmn->lock);
201
202 it = interval_tree_iter_first(&rmn->objects, start, end);
203 while (it) {
204 struct amdgpu_mn_node *node;
205
206 node = container_of(it, struct amdgpu_mn_node, it);
207 it = interval_tree_iter_next(it, start, end);
208
209 amdgpu_mn_invalidate_node(node, start, end);
210 }
211
212 mutex_unlock(&rmn->lock);
213 }
214
215 static const struct mmu_notifier_ops amdgpu_mn_ops = {
216 .release = amdgpu_mn_release,
217 .invalidate_page = amdgpu_mn_invalidate_page,
218 .invalidate_range_start = amdgpu_mn_invalidate_range_start,
219 };
220
221 /**
222 * amdgpu_mn_get - create notifier context
223 *
224 * @adev: amdgpu device pointer
225 *
226 * Creates a notifier context for current->mm.
227 */
amdgpu_mn_get(struct amdgpu_device * adev)228 static struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev)
229 {
230 struct mm_struct *mm = current->mm;
231 struct amdgpu_mn *rmn;
232 int r;
233
234 mutex_lock(&adev->mn_lock);
235 if (down_write_killable(&mm->mmap_sem)) {
236 mutex_unlock(&adev->mn_lock);
237 return ERR_PTR(-EINTR);
238 }
239
240 hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
241 if (rmn->mm == mm)
242 goto release_locks;
243
244 rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
245 if (!rmn) {
246 rmn = ERR_PTR(-ENOMEM);
247 goto release_locks;
248 }
249
250 rmn->adev = adev;
251 rmn->mm = mm;
252 rmn->mn.ops = &amdgpu_mn_ops;
253 mutex_init(&rmn->lock);
254 rmn->objects = RB_ROOT;
255
256 r = __mmu_notifier_register(&rmn->mn, mm);
257 if (r)
258 goto free_rmn;
259
260 hash_add(adev->mn_hash, &rmn->node, (unsigned long)mm);
261
262 release_locks:
263 up_write(&mm->mmap_sem);
264 mutex_unlock(&adev->mn_lock);
265
266 return rmn;
267
268 free_rmn:
269 up_write(&mm->mmap_sem);
270 mutex_unlock(&adev->mn_lock);
271 kfree(rmn);
272
273 return ERR_PTR(r);
274 }
275
276 /**
277 * amdgpu_mn_register - register a BO for notifier updates
278 *
279 * @bo: amdgpu buffer object
280 * @addr: userptr addr we should monitor
281 *
282 * Registers an MMU notifier for the given BO at the specified address.
283 * Returns 0 on success, -ERRNO if anything goes wrong.
284 */
amdgpu_mn_register(struct amdgpu_bo * bo,unsigned long addr)285 int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
286 {
287 unsigned long end = addr + amdgpu_bo_size(bo) - 1;
288 struct amdgpu_device *adev = bo->adev;
289 struct amdgpu_mn *rmn;
290 struct amdgpu_mn_node *node = NULL;
291 struct list_head bos;
292 struct interval_tree_node *it;
293
294 rmn = amdgpu_mn_get(adev);
295 if (IS_ERR(rmn))
296 return PTR_ERR(rmn);
297
298 INIT_LIST_HEAD(&bos);
299
300 mutex_lock(&rmn->lock);
301
302 while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
303 kfree(node);
304 node = container_of(it, struct amdgpu_mn_node, it);
305 interval_tree_remove(&node->it, &rmn->objects);
306 addr = min(it->start, addr);
307 end = max(it->last, end);
308 list_splice(&node->bos, &bos);
309 }
310
311 if (!node) {
312 node = kmalloc(sizeof(struct amdgpu_mn_node), GFP_KERNEL);
313 if (!node) {
314 mutex_unlock(&rmn->lock);
315 return -ENOMEM;
316 }
317 }
318
319 bo->mn = rmn;
320
321 node->it.start = addr;
322 node->it.last = end;
323 INIT_LIST_HEAD(&node->bos);
324 list_splice(&bos, &node->bos);
325 list_add(&bo->mn_list, &node->bos);
326
327 interval_tree_insert(&node->it, &rmn->objects);
328
329 mutex_unlock(&rmn->lock);
330
331 return 0;
332 }
333
334 /**
335 * amdgpu_mn_unregister - unregister a BO for notifier updates
336 *
337 * @bo: amdgpu buffer object
338 *
339 * Remove any registration of MMU notifier updates from the buffer object.
340 */
amdgpu_mn_unregister(struct amdgpu_bo * bo)341 void amdgpu_mn_unregister(struct amdgpu_bo *bo)
342 {
343 struct amdgpu_device *adev = bo->adev;
344 struct amdgpu_mn *rmn;
345 struct list_head *head;
346
347 mutex_lock(&adev->mn_lock);
348
349 rmn = bo->mn;
350 if (rmn == NULL) {
351 mutex_unlock(&adev->mn_lock);
352 return;
353 }
354
355 mutex_lock(&rmn->lock);
356
357 /* save the next list entry for later */
358 head = bo->mn_list.next;
359
360 bo->mn = NULL;
361 list_del(&bo->mn_list);
362
363 if (list_empty(head)) {
364 struct amdgpu_mn_node *node;
365 node = container_of(head, struct amdgpu_mn_node, bos);
366 interval_tree_remove(&node->it, &rmn->objects);
367 kfree(node);
368 }
369
370 mutex_unlock(&rmn->lock);
371 mutex_unlock(&adev->mn_lock);
372 }
373