xref: /linux/drivers/gpu/drm/radeon/radeon_mn.c (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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  */
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  */
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  */
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 			r = radeon_bo_reserve(bo, true);
146 			if (r) {
147 				DRM_ERROR("(%ld) failed to reserve user bo\n", r);
148 				continue;
149 			}
150 
151 			r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
152 				true, false, MAX_SCHEDULE_TIMEOUT);
153 			if (r <= 0)
154 				DRM_ERROR("(%ld) failed to wait for user bo\n", r);
155 
156 			radeon_ttm_placement_from_domain(bo, RADEON_GEM_DOMAIN_CPU);
157 			r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
158 			if (r)
159 				DRM_ERROR("(%ld) failed to validate user bo\n", r);
160 
161 			radeon_bo_unreserve(bo);
162 		}
163 	}
164 
165 	mutex_unlock(&rmn->lock);
166 }
167 
168 static const struct mmu_notifier_ops radeon_mn_ops = {
169 	.release = radeon_mn_release,
170 	.invalidate_range_start = radeon_mn_invalidate_range_start,
171 };
172 
173 /**
174  * radeon_mn_get - create notifier context
175  *
176  * @rdev: radeon device pointer
177  *
178  * Creates a notifier context for current->mm.
179  */
180 static struct radeon_mn *radeon_mn_get(struct radeon_device *rdev)
181 {
182 	struct mm_struct *mm = current->mm;
183 	struct radeon_mn *rmn;
184 	int r;
185 
186 	down_write(&mm->mmap_sem);
187 	mutex_lock(&rdev->mn_lock);
188 
189 	hash_for_each_possible(rdev->mn_hash, rmn, node, (unsigned long)mm)
190 		if (rmn->mm == mm)
191 			goto release_locks;
192 
193 	rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
194 	if (!rmn) {
195 		rmn = ERR_PTR(-ENOMEM);
196 		goto release_locks;
197 	}
198 
199 	rmn->rdev = rdev;
200 	rmn->mm = mm;
201 	rmn->mn.ops = &radeon_mn_ops;
202 	mutex_init(&rmn->lock);
203 	rmn->objects = RB_ROOT;
204 
205 	r = __mmu_notifier_register(&rmn->mn, mm);
206 	if (r)
207 		goto free_rmn;
208 
209 	hash_add(rdev->mn_hash, &rmn->node, (unsigned long)mm);
210 
211 release_locks:
212 	mutex_unlock(&rdev->mn_lock);
213 	up_write(&mm->mmap_sem);
214 
215 	return rmn;
216 
217 free_rmn:
218 	mutex_unlock(&rdev->mn_lock);
219 	up_write(&mm->mmap_sem);
220 	kfree(rmn);
221 
222 	return ERR_PTR(r);
223 }
224 
225 /**
226  * radeon_mn_register - register a BO for notifier updates
227  *
228  * @bo: radeon buffer object
229  * @addr: userptr addr we should monitor
230  *
231  * Registers an MMU notifier for the given BO at the specified address.
232  * Returns 0 on success, -ERRNO if anything goes wrong.
233  */
234 int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
235 {
236 	unsigned long end = addr + radeon_bo_size(bo) - 1;
237 	struct radeon_device *rdev = bo->rdev;
238 	struct radeon_mn *rmn;
239 	struct radeon_mn_node *node = NULL;
240 	struct list_head bos;
241 	struct interval_tree_node *it;
242 
243 	rmn = radeon_mn_get(rdev);
244 	if (IS_ERR(rmn))
245 		return PTR_ERR(rmn);
246 
247 	INIT_LIST_HEAD(&bos);
248 
249 	mutex_lock(&rmn->lock);
250 
251 	while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
252 		kfree(node);
253 		node = container_of(it, struct radeon_mn_node, it);
254 		interval_tree_remove(&node->it, &rmn->objects);
255 		addr = min(it->start, addr);
256 		end = max(it->last, end);
257 		list_splice(&node->bos, &bos);
258 	}
259 
260 	if (!node) {
261 		node = kmalloc(sizeof(struct radeon_mn_node), GFP_KERNEL);
262 		if (!node) {
263 			mutex_unlock(&rmn->lock);
264 			return -ENOMEM;
265 		}
266 	}
267 
268 	bo->mn = rmn;
269 
270 	node->it.start = addr;
271 	node->it.last = end;
272 	INIT_LIST_HEAD(&node->bos);
273 	list_splice(&bos, &node->bos);
274 	list_add(&bo->mn_list, &node->bos);
275 
276 	interval_tree_insert(&node->it, &rmn->objects);
277 
278 	mutex_unlock(&rmn->lock);
279 
280 	return 0;
281 }
282 
283 /**
284  * radeon_mn_unregister - unregister a BO for notifier updates
285  *
286  * @bo: radeon buffer object
287  *
288  * Remove any registration of MMU notifier updates from the buffer object.
289  */
290 void radeon_mn_unregister(struct radeon_bo *bo)
291 {
292 	struct radeon_device *rdev = bo->rdev;
293 	struct radeon_mn *rmn;
294 	struct list_head *head;
295 
296 	mutex_lock(&rdev->mn_lock);
297 	rmn = bo->mn;
298 	if (rmn == NULL) {
299 		mutex_unlock(&rdev->mn_lock);
300 		return;
301 	}
302 
303 	mutex_lock(&rmn->lock);
304 	/* save the next list entry for later */
305 	head = bo->mn_list.next;
306 
307 	bo->mn = NULL;
308 	list_del(&bo->mn_list);
309 
310 	if (list_empty(head)) {
311 		struct radeon_mn_node *node;
312 		node = container_of(head, struct radeon_mn_node, bos);
313 		interval_tree_remove(&node->it, &rmn->objects);
314 		kfree(node);
315 	}
316 
317 	mutex_unlock(&rmn->lock);
318 	mutex_unlock(&rdev->mn_lock);
319 }
320