xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/amd/amdgpu/amdgpu_mn.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*	$NetBSD: amdgpu_mn.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $	*/
2 
3 /*
4  * Copyright 2014 Advanced Micro Devices, Inc.
5  * All Rights Reserved.
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a
8  * copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sub license, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
19  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
20  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
21  * USE OR OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * The above copyright notice and this permission notice (including the
24  * next paragraph) shall be included in all copies or substantial portions
25  * of the Software.
26  *
27  */
28 /*
29  * Authors:
30  *    Christian König <christian.koenig@amd.com>
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: amdgpu_mn.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $");
35 
36 #include <linux/firmware.h>
37 #include <linux/module.h>
38 #include <linux/mmu_notifier.h>
39 #include <drm/drmP.h>
40 #include <drm/drm.h>
41 
42 #include "amdgpu.h"
43 
44 struct amdgpu_mn {
45 	/* constant after initialisation */
46 	struct amdgpu_device	*adev;
47 	struct mm_struct	*mm;
48 	struct mmu_notifier	mn;
49 
50 	/* only used on destruction */
51 	struct work_struct	work;
52 
53 	/* protected by adev->mn_lock */
54 	struct hlist_node	node;
55 
56 	/* objects protected by lock */
57 	struct mutex		lock;
58 	struct rb_root		objects;
59 };
60 
61 struct amdgpu_mn_node {
62 	struct interval_tree_node	it;
63 	struct list_head		bos;
64 };
65 
66 /**
67  * amdgpu_mn_destroy - destroy the rmn
68  *
69  * @work: previously sheduled work item
70  *
71  * Lazy destroys the notifier from a work item
72  */
73 static void amdgpu_mn_destroy(struct work_struct *work)
74 {
75 	struct amdgpu_mn *rmn = container_of(work, struct amdgpu_mn, work);
76 	struct amdgpu_device *adev = rmn->adev;
77 	struct amdgpu_mn_node *node, *next_node;
78 	struct amdgpu_bo *bo, *next_bo;
79 
80 	mutex_lock(&adev->mn_lock);
81 	mutex_lock(&rmn->lock);
82 	hash_del(&rmn->node);
83 	rbtree_postorder_for_each_entry_safe(node, next_node, &rmn->objects,
84 					     it.rb) {
85 
86 		interval_tree_remove(&node->it, &rmn->objects);
87 		list_for_each_entry_safe(bo, next_bo, &node->bos, mn_list) {
88 			bo->mn = NULL;
89 			list_del_init(&bo->mn_list);
90 		}
91 		kfree(node);
92 	}
93 	mutex_unlock(&rmn->lock);
94 	mutex_unlock(&adev->mn_lock);
95 	mmu_notifier_unregister(&rmn->mn, rmn->mm);
96 	kfree(rmn);
97 }
98 
99 /**
100  * amdgpu_mn_release - callback to notify about mm destruction
101  *
102  * @mn: our notifier
103  * @mn: the mm this callback is about
104  *
105  * Shedule a work item to lazy destroy our notifier.
106  */
107 static void amdgpu_mn_release(struct mmu_notifier *mn,
108 			      struct mm_struct *mm)
109 {
110 	struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
111 	INIT_WORK(&rmn->work, amdgpu_mn_destroy);
112 	schedule_work(&rmn->work);
113 }
114 
115 /**
116  * amdgpu_mn_invalidate_range_start - callback to notify about mm change
117  *
118  * @mn: our notifier
119  * @mn: the mm this callback is about
120  * @start: start of updated range
121  * @end: end of updated range
122  *
123  * We block for all BOs between start and end to be idle and
124  * unmap them by move them into system domain again.
125  */
126 static void amdgpu_mn_invalidate_range_start(struct mmu_notifier *mn,
127 					     struct mm_struct *mm,
128 					     unsigned long start,
129 					     unsigned long end)
130 {
131 	struct amdgpu_mn *rmn = container_of(mn, struct amdgpu_mn, mn);
132 	struct interval_tree_node *it;
133 
134 	/* notification is exclusive, but interval is inclusive */
135 	end -= 1;
136 
137 	mutex_lock(&rmn->lock);
138 
139 	it = interval_tree_iter_first(&rmn->objects, start, end);
140 	while (it) {
141 		struct amdgpu_mn_node *node;
142 		struct amdgpu_bo *bo;
143 		long r;
144 
145 		node = container_of(it, struct amdgpu_mn_node, it);
146 		it = interval_tree_iter_next(it, start, end);
147 
148 		list_for_each_entry(bo, &node->bos, mn_list) {
149 
150 			if (!amdgpu_ttm_tt_affect_userptr(bo->tbo.ttm, start,
151 							  end))
152 				continue;
153 
154 			r = amdgpu_bo_reserve(bo, true);
155 			if (r) {
156 				DRM_ERROR("(%ld) failed to reserve user bo\n", r);
157 				continue;
158 			}
159 
160 			r = reservation_object_wait_timeout_rcu(bo->tbo.resv,
161 				true, false, MAX_SCHEDULE_TIMEOUT);
162 			if (r <= 0)
163 				DRM_ERROR("(%ld) failed to wait for user bo\n", r);
164 
165 			amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
166 			r = ttm_bo_validate(&bo->tbo, &bo->placement, false, false);
167 			if (r)
168 				DRM_ERROR("(%ld) failed to validate user bo\n", r);
169 
170 			amdgpu_bo_unreserve(bo);
171 		}
172 	}
173 
174 	mutex_unlock(&rmn->lock);
175 }
176 
177 static const struct mmu_notifier_ops amdgpu_mn_ops = {
178 	.release = amdgpu_mn_release,
179 	.invalidate_range_start = amdgpu_mn_invalidate_range_start,
180 };
181 
182 /**
183  * amdgpu_mn_get - create notifier context
184  *
185  * @adev: amdgpu device pointer
186  *
187  * Creates a notifier context for current->mm.
188  */
189 static struct amdgpu_mn *amdgpu_mn_get(struct amdgpu_device *adev)
190 {
191 	struct mm_struct *mm = current->mm;
192 	struct amdgpu_mn *rmn;
193 	int r;
194 
195 	down_write(&mm->mmap_sem);
196 	mutex_lock(&adev->mn_lock);
197 
198 	hash_for_each_possible(adev->mn_hash, rmn, node, (unsigned long)mm)
199 		if (rmn->mm == mm)
200 			goto release_locks;
201 
202 	rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
203 	if (!rmn) {
204 		rmn = ERR_PTR(-ENOMEM);
205 		goto release_locks;
206 	}
207 
208 	rmn->adev = adev;
209 	rmn->mm = mm;
210 	rmn->mn.ops = &amdgpu_mn_ops;
211 	mutex_init(&rmn->lock);
212 	rmn->objects = RB_ROOT;
213 
214 	r = __mmu_notifier_register(&rmn->mn, mm);
215 	if (r)
216 		goto free_rmn;
217 
218 	hash_add(adev->mn_hash, &rmn->node, (unsigned long)mm);
219 
220 release_locks:
221 	mutex_unlock(&adev->mn_lock);
222 	up_write(&mm->mmap_sem);
223 
224 	return rmn;
225 
226 free_rmn:
227 	mutex_unlock(&adev->mn_lock);
228 	up_write(&mm->mmap_sem);
229 	kfree(rmn);
230 
231 	return ERR_PTR(r);
232 }
233 
234 /**
235  * amdgpu_mn_register - register a BO for notifier updates
236  *
237  * @bo: amdgpu buffer object
238  * @addr: userptr addr we should monitor
239  *
240  * Registers an MMU notifier for the given BO at the specified address.
241  * Returns 0 on success, -ERRNO if anything goes wrong.
242  */
243 int amdgpu_mn_register(struct amdgpu_bo *bo, unsigned long addr)
244 {
245 	unsigned long end = addr + amdgpu_bo_size(bo) - 1;
246 	struct amdgpu_device *adev = bo->adev;
247 	struct amdgpu_mn *rmn;
248 	struct amdgpu_mn_node *node = NULL;
249 	struct list_head bos;
250 	struct interval_tree_node *it;
251 
252 	rmn = amdgpu_mn_get(adev);
253 	if (IS_ERR(rmn))
254 		return PTR_ERR(rmn);
255 
256 	INIT_LIST_HEAD(&bos);
257 
258 	mutex_lock(&rmn->lock);
259 
260 	while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
261 		kfree(node);
262 		node = container_of(it, struct amdgpu_mn_node, it);
263 		interval_tree_remove(&node->it, &rmn->objects);
264 		addr = min(it->start, addr);
265 		end = max(it->last, end);
266 		list_splice(&node->bos, &bos);
267 	}
268 
269 	if (!node) {
270 		node = kmalloc(sizeof(struct amdgpu_mn_node), GFP_KERNEL);
271 		if (!node) {
272 			mutex_unlock(&rmn->lock);
273 			return -ENOMEM;
274 		}
275 	}
276 
277 	bo->mn = rmn;
278 
279 	node->it.start = addr;
280 	node->it.last = end;
281 	INIT_LIST_HEAD(&node->bos);
282 	list_splice(&bos, &node->bos);
283 	list_add(&bo->mn_list, &node->bos);
284 
285 	interval_tree_insert(&node->it, &rmn->objects);
286 
287 	mutex_unlock(&rmn->lock);
288 
289 	return 0;
290 }
291 
292 /**
293  * amdgpu_mn_unregister - unregister a BO for notifier updates
294  *
295  * @bo: amdgpu buffer object
296  *
297  * Remove any registration of MMU notifier updates from the buffer object.
298  */
299 void amdgpu_mn_unregister(struct amdgpu_bo *bo)
300 {
301 	struct amdgpu_device *adev = bo->adev;
302 	struct amdgpu_mn *rmn;
303 	struct list_head *head;
304 
305 	mutex_lock(&adev->mn_lock);
306 	rmn = bo->mn;
307 	if (rmn == NULL) {
308 		mutex_unlock(&adev->mn_lock);
309 		return;
310 	}
311 
312 	mutex_lock(&rmn->lock);
313 	/* save the next list entry for later */
314 	head = bo->mn_list.next;
315 
316 	bo->mn = NULL;
317 	list_del(&bo->mn_list);
318 
319 	if (list_empty(head)) {
320 		struct amdgpu_mn_node *node;
321 		node = container_of(head, struct amdgpu_mn_node, bos);
322 		interval_tree_remove(&node->it, &rmn->objects);
323 		kfree(node);
324 	}
325 
326 	mutex_unlock(&rmn->lock);
327 	mutex_unlock(&adev->mn_lock);
328 }
329