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 "radeon.h"
38
39 struct radeon_mn {
40 /* constant after initialisation */
41 struct radeon_device *rdev;
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 rdev->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 radeon_mn_node {
57 struct interval_tree_node it;
58 struct list_head bos;
59 };
60
61 /**
62 * radeon_mn_destroy - destroy the rmn
63 *
64 * @work: previously sheduled work item
65 *
66 * Lazy destroys the notifier from a work item
67 */
radeon_mn_destroy(struct work_struct * work)68 static void radeon_mn_destroy(struct work_struct *work)
69 {
70 struct radeon_mn *rmn = container_of(work, struct radeon_mn, work);
71 struct radeon_device *rdev = rmn->rdev;
72 struct radeon_mn_node *node, *next_node;
73 struct radeon_bo *bo, *next_bo;
74
75 mutex_lock(&rdev->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
81 interval_tree_remove(&node->it, &rmn->objects);
82 list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
83 bo->mn = NULL;
84 list_del_init(&bo->mn_list);
85 }
86 kfree(node);
87 }
88 mutex_unlock(&rmn->lock);
89 mutex_unlock(&rdev->mn_lock);
90 mmu_notifier_unregister(&rmn->mn, rmn->mm);
91 kfree(rmn);
92 }
93
94 /**
95 * radeon_mn_release - callback to notify about mm destruction
96 *
97 * @mn: our notifier
98 * @mn: the mm this callback is about
99 *
100 * Shedule a work item to lazy destroy our notifier.
101 */
radeon_mn_release(struct mmu_notifier * mn,struct mm_struct * mm)102 static void radeon_mn_release(struct mmu_notifier *mn,
103 struct mm_struct *mm)
104 {
105 struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
106 INIT_WORK(&rmn->work, radeon_mn_destroy);
107 schedule_work(&rmn->work);
108 }
109
110 /**
111 * radeon_mn_invalidate_range_start - callback to notify about mm change
112 *
113 * @mn: our notifier
114 * @mn: the mm this callback is about
115 * @start: start of updated range
116 * @end: end of updated range
117 *
118 * We block for all BOs between start and end to be idle and
119 * unmap them by move them into system domain again.
120 */
radeon_mn_invalidate_range_start(struct mmu_notifier * mn,struct mm_struct * mm,unsigned long start,unsigned long end)121 static void radeon_mn_invalidate_range_start(struct mmu_notifier *mn,
122 struct mm_struct *mm,
123 unsigned long start,
124 unsigned long end)
125 {
126 struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
127 struct interval_tree_node *it;
128
129 /* notification is exclusive, but interval is inclusive */
130 end -= 1;
131
132 mutex_lock(&rmn->lock);
133
134 it = interval_tree_iter_first(&rmn->objects, start, end);
135 while (it) {
136 struct radeon_mn_node *node;
137 struct radeon_bo *bo;
138 long r;
139
140 node = container_of(it, struct radeon_mn_node, it);
141 it = interval_tree_iter_next(it, start, end);
142
143 list_for_each_entry(bo, &node->bos, mn_list) {
144
145 if (!bo->tbo.ttm || bo->tbo.ttm->state != tt_bound)
146 continue;
147
148 r = radeon_bo_reserve(bo, true);
149 if (r) {
150 DRM_ERROR("(%ld) failed to reserve user bo\n", r);
151 continue;
152 }
153
154 r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
155 true, false, MAX_SCHEDULE_TIMEOUT);
156 if (r <= 0)
157 DRM_ERROR("(%ld) failed to wait for user bo\n", r);
158
159 radeon_ttm_placement_from_domain(bo, RADEON_GEM_DOMAIN_CPU);
160 r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
161 if (r)
162 DRM_ERROR("(%ld) failed to validate user bo\n", r);
163
164 radeon_bo_unreserve(bo);
165 }
166 }
167
168 mutex_unlock(&rmn->lock);
169 }
170
171 static const struct mmu_notifier_ops radeon_mn_ops = {
172 .release = radeon_mn_release,
173 .invalidate_range_start = radeon_mn_invalidate_range_start,
174 };
175
176 /**
177 * radeon_mn_get - create notifier context
178 *
179 * @rdev: radeon device pointer
180 *
181 * Creates a notifier context for current->mm.
182 */
radeon_mn_get(struct radeon_device * rdev)183 static struct radeon_mn *radeon_mn_get(struct radeon_device *rdev)
184 {
185 struct mm_struct *mm = current->mm;
186 struct radeon_mn *rmn;
187 int r;
188
189 if (down_write_killable(&mm->mmap_sem))
190 return ERR_PTR(-EINTR);
191
192 mutex_lock(&rdev->mn_lock);
193
194 hash_for_each_possible(rdev->mn_hash, rmn, node, (unsigned long)mm)
195 if (rmn->mm == mm)
196 goto release_locks;
197
198 rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
199 if (!rmn) {
200 rmn = ERR_PTR(-ENOMEM);
201 goto release_locks;
202 }
203
204 rmn->rdev = rdev;
205 rmn->mm = mm;
206 rmn->mn.ops = &radeon_mn_ops;
207 mutex_init(&rmn->lock);
208 rmn->objects = LINUX_RB_ROOT;
209
210 r = __mmu_notifier_register(&rmn->mn, mm);
211 if (r)
212 goto free_rmn;
213
214 hash_add(rdev->mn_hash, &rmn->node, (unsigned long)mm);
215
216 release_locks:
217 mutex_unlock(&rdev->mn_lock);
218 up_write(&mm->mmap_sem);
219
220 return rmn;
221
222 free_rmn:
223 mutex_unlock(&rdev->mn_lock);
224 up_write(&mm->mmap_sem);
225 kfree(rmn);
226
227 return ERR_PTR(r);
228 }
229
230 /**
231 * radeon_mn_register - register a BO for notifier updates
232 *
233 * @bo: radeon buffer object
234 * @addr: userptr addr we should monitor
235 *
236 * Registers an MMU notifier for the given BO at the specified address.
237 * Returns 0 on success, -ERRNO if anything goes wrong.
238 */
radeon_mn_register(struct radeon_bo * bo,unsigned long addr)239 int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
240 {
241 unsigned long end = addr + radeon_bo_size(bo) - 1;
242 struct radeon_device *rdev = bo->rdev;
243 struct radeon_mn *rmn;
244 struct radeon_mn_node *node = NULL;
245 struct list_head bos;
246 struct interval_tree_node *it;
247
248 rmn = radeon_mn_get(rdev);
249 if (IS_ERR(rmn))
250 return PTR_ERR(rmn);
251
252 INIT_LIST_HEAD(&bos);
253
254 mutex_lock(&rmn->lock);
255
256 while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
257 kfree(node);
258 node = container_of(it, struct radeon_mn_node, it);
259 interval_tree_remove(&node->it, &rmn->objects);
260 addr = min(it->start, addr);
261 end = max(it->last, end);
262 list_splice(&node->bos, &bos);
263 }
264
265 if (!node) {
266 node = kmalloc(sizeof(struct radeon_mn_node), M_DRM,
267 GFP_KERNEL);
268 if (!node) {
269 mutex_unlock(&rmn->lock);
270 return -ENOMEM;
271 }
272 }
273
274 bo->mn = rmn;
275
276 node->it.start = addr;
277 node->it.last = end;
278 INIT_LIST_HEAD(&node->bos);
279 list_splice(&bos, &node->bos);
280 list_add(&bo->mn_list, &node->bos);
281
282 interval_tree_insert(&node->it, &rmn->objects);
283
284 mutex_unlock(&rmn->lock);
285
286 return 0;
287 }
288
289 /**
290 * radeon_mn_unregister - unregister a BO for notifier updates
291 *
292 * @bo: radeon buffer object
293 *
294 * Remove any registration of MMU notifier updates from the buffer object.
295 */
radeon_mn_unregister(struct radeon_bo * bo)296 void radeon_mn_unregister(struct radeon_bo *bo)
297 {
298 struct radeon_device *rdev = bo->rdev;
299 struct radeon_mn *rmn;
300 struct list_head *head;
301
302 mutex_lock(&rdev->mn_lock);
303 rmn = bo->mn;
304 if (rmn == NULL) {
305 mutex_unlock(&rdev->mn_lock);
306 return;
307 }
308
309 mutex_lock(&rmn->lock);
310 /* save the next list entry for later */
311 head = bo->mn_list.next;
312
313 bo->mn = NULL;
314 list_del(&bo->mn_list);
315
316 if (list_empty(head)) {
317 struct radeon_mn_node *node;
318 node = container_of(head, struct radeon_mn_node, bos);
319 interval_tree_remove(&node->it, &rmn->objects);
320 kfree(node);
321 }
322
323 mutex_unlock(&rmn->lock);
324 mutex_unlock(&rdev->mn_lock);
325 }
326