xref: /openbmc/linux/drivers/gpu/drm/radeon/radeon_mn.c (revision d9e32672)
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 
35 #include <drm/drm.h>
36 
37 #include "radeon.h"
38 
39 struct radeon_mn {
40 	struct mmu_notifier	mn;
41 
42 	/* objects protected by lock */
43 	struct mutex		lock;
44 	struct rb_root_cached	objects;
45 };
46 
47 struct radeon_mn_node {
48 	struct interval_tree_node	it;
49 	struct list_head		bos;
50 };
51 
52 /**
53  * radeon_mn_invalidate_range_start - callback to notify about mm change
54  *
55  * @mn: our notifier
56  * @mn: the mm this callback is about
57  * @start: start of updated range
58  * @end: end of updated range
59  *
60  * We block for all BOs between start and end to be idle and
61  * unmap them by move them into system domain again.
62  */
63 static int radeon_mn_invalidate_range_start(struct mmu_notifier *mn,
64 				const struct mmu_notifier_range *range)
65 {
66 	struct radeon_mn *rmn = container_of(mn, struct radeon_mn, mn);
67 	struct ttm_operation_ctx ctx = { false, false };
68 	struct interval_tree_node *it;
69 	unsigned long end;
70 	int ret = 0;
71 
72 	/* notification is exclusive, but interval is inclusive */
73 	end = range->end - 1;
74 
75 	/* TODO we should be able to split locking for interval tree and
76 	 * the tear down.
77 	 */
78 	if (mmu_notifier_range_blockable(range))
79 		mutex_lock(&rmn->lock);
80 	else if (!mutex_trylock(&rmn->lock))
81 		return -EAGAIN;
82 
83 	it = interval_tree_iter_first(&rmn->objects, range->start, end);
84 	while (it) {
85 		struct radeon_mn_node *node;
86 		struct radeon_bo *bo;
87 		long r;
88 
89 		if (!mmu_notifier_range_blockable(range)) {
90 			ret = -EAGAIN;
91 			goto out_unlock;
92 		}
93 
94 		node = container_of(it, struct radeon_mn_node, it);
95 		it = interval_tree_iter_next(it, range->start, end);
96 
97 		list_for_each_entry(bo, &node->bos, mn_list) {
98 
99 			if (!bo->tbo.ttm || bo->tbo.ttm->state != tt_bound)
100 				continue;
101 
102 			r = radeon_bo_reserve(bo, true);
103 			if (r) {
104 				DRM_ERROR("(%ld) failed to reserve user bo\n", r);
105 				continue;
106 			}
107 
108 			r = dma_resv_wait_timeout_rcu(bo->tbo.base.resv,
109 				true, false, MAX_SCHEDULE_TIMEOUT);
110 			if (r <= 0)
111 				DRM_ERROR("(%ld) failed to wait for user bo\n", r);
112 
113 			radeon_ttm_placement_from_domain(bo, RADEON_GEM_DOMAIN_CPU);
114 			r = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
115 			if (r)
116 				DRM_ERROR("(%ld) failed to validate user bo\n", r);
117 
118 			radeon_bo_unreserve(bo);
119 		}
120 	}
121 
122 out_unlock:
123 	mutex_unlock(&rmn->lock);
124 
125 	return ret;
126 }
127 
128 static void radeon_mn_release(struct mmu_notifier *mn, struct mm_struct *mm)
129 {
130 	struct mmu_notifier_range range = {
131 		.mm = mm,
132 		.start = 0,
133 		.end = ULONG_MAX,
134 		.flags = 0,
135 		.event = MMU_NOTIFY_UNMAP,
136 	};
137 
138 	radeon_mn_invalidate_range_start(mn, &range);
139 }
140 
141 static struct mmu_notifier *radeon_mn_alloc_notifier(struct mm_struct *mm)
142 {
143 	struct radeon_mn *rmn;
144 
145 	rmn = kzalloc(sizeof(*rmn), GFP_KERNEL);
146 	if (!rmn)
147 		return ERR_PTR(-ENOMEM);
148 
149 	mutex_init(&rmn->lock);
150 	rmn->objects = RB_ROOT_CACHED;
151 	return &rmn->mn;
152 }
153 
154 static void radeon_mn_free_notifier(struct mmu_notifier *mn)
155 {
156 	kfree(container_of(mn, struct radeon_mn, mn));
157 }
158 
159 static const struct mmu_notifier_ops radeon_mn_ops = {
160 	.release = radeon_mn_release,
161 	.invalidate_range_start = radeon_mn_invalidate_range_start,
162 	.alloc_notifier = radeon_mn_alloc_notifier,
163 	.free_notifier = radeon_mn_free_notifier,
164 };
165 
166 /**
167  * radeon_mn_register - register a BO for notifier updates
168  *
169  * @bo: radeon buffer object
170  * @addr: userptr addr we should monitor
171  *
172  * Registers an MMU notifier for the given BO at the specified address.
173  * Returns 0 on success, -ERRNO if anything goes wrong.
174  */
175 int radeon_mn_register(struct radeon_bo *bo, unsigned long addr)
176 {
177 	unsigned long end = addr + radeon_bo_size(bo) - 1;
178 	struct mmu_notifier *mn;
179 	struct radeon_mn *rmn;
180 	struct radeon_mn_node *node = NULL;
181 	struct list_head bos;
182 	struct interval_tree_node *it;
183 
184 	mn = mmu_notifier_get(&radeon_mn_ops, current->mm);
185 	if (IS_ERR(mn))
186 		return PTR_ERR(mn);
187 	rmn = container_of(mn, struct radeon_mn, mn);
188 
189 	INIT_LIST_HEAD(&bos);
190 
191 	mutex_lock(&rmn->lock);
192 
193 	while ((it = interval_tree_iter_first(&rmn->objects, addr, end))) {
194 		kfree(node);
195 		node = container_of(it, struct radeon_mn_node, it);
196 		interval_tree_remove(&node->it, &rmn->objects);
197 		addr = min(it->start, addr);
198 		end = max(it->last, end);
199 		list_splice(&node->bos, &bos);
200 	}
201 
202 	if (!node) {
203 		node = kmalloc(sizeof(struct radeon_mn_node), GFP_KERNEL);
204 		if (!node) {
205 			mutex_unlock(&rmn->lock);
206 			return -ENOMEM;
207 		}
208 	}
209 
210 	bo->mn = rmn;
211 
212 	node->it.start = addr;
213 	node->it.last = end;
214 	INIT_LIST_HEAD(&node->bos);
215 	list_splice(&bos, &node->bos);
216 	list_add(&bo->mn_list, &node->bos);
217 
218 	interval_tree_insert(&node->it, &rmn->objects);
219 
220 	mutex_unlock(&rmn->lock);
221 
222 	return 0;
223 }
224 
225 /**
226  * radeon_mn_unregister - unregister a BO for notifier updates
227  *
228  * @bo: radeon buffer object
229  *
230  * Remove any registration of MMU notifier updates from the buffer object.
231  */
232 void radeon_mn_unregister(struct radeon_bo *bo)
233 {
234 	struct radeon_mn *rmn = bo->mn;
235 	struct list_head *head;
236 
237 	if (!rmn)
238 		return;
239 
240 	mutex_lock(&rmn->lock);
241 	/* save the next list entry for later */
242 	head = bo->mn_list.next;
243 
244 	list_del(&bo->mn_list);
245 
246 	if (list_empty(head)) {
247 		struct radeon_mn_node *node;
248 		node = container_of(head, struct radeon_mn_node, bos);
249 		interval_tree_remove(&node->it, &rmn->objects);
250 		kfree(node);
251 	}
252 
253 	mutex_unlock(&rmn->lock);
254 
255 	mmu_notifier_put(&rmn->mn);
256 	bo->mn = NULL;
257 }
258