1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */
2
3 /*
4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
5 * Copyright 2020 Advanced Micro Devices, Inc.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the "Software"),
9 * to deal in the Software without restriction, including without limitation
10 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
11 * and/or sell copies of the Software, and to permit persons to whom the
12 * Software is furnished to do so, subject to the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
21 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
22 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
23 * OTHER DEALINGS IN THE SOFTWARE.
24 *
25 * Authors: Christian König
26 */
27
28 #define pr_fmt(fmt) "[TTM DEVICE] " fmt
29
30 #include <linux/debugfs.h>
31 #include <linux/mm.h>
32
33 #include <drm/ttm/ttm_bo.h>
34 #include <drm/ttm/ttm_device.h>
35 #include <drm/ttm/ttm_tt.h>
36 #include <drm/ttm/ttm_placement.h>
37
38 #include "ttm_module.h"
39
40 /*
41 * ttm_global_mutex - protecting the global state
42 */
43 static DEFINE_MUTEX(ttm_global_mutex);
44 static unsigned ttm_glob_use_count;
45 struct ttm_global ttm_glob;
46 EXPORT_SYMBOL(ttm_glob);
47
48 struct dentry *ttm_debugfs_root;
49
ttm_global_release(void)50 static void ttm_global_release(void)
51 {
52 struct ttm_global *glob = &ttm_glob;
53
54 mutex_lock(&ttm_global_mutex);
55 if (--ttm_glob_use_count > 0)
56 goto out;
57
58 ttm_pool_mgr_fini();
59 debugfs_remove(ttm_debugfs_root);
60
61 __free_page(glob->dummy_read_page);
62 memset(glob, 0, sizeof(*glob));
63 out:
64 mutex_unlock(&ttm_global_mutex);
65 }
66
ttm_global_init(void)67 static int ttm_global_init(void)
68 {
69 struct ttm_global *glob = &ttm_glob;
70 unsigned long num_pages, num_dma32;
71 struct sysinfo si;
72 int ret = 0;
73
74 mutex_lock(&ttm_global_mutex);
75 if (++ttm_glob_use_count > 1)
76 goto out;
77
78 si_meminfo(&si);
79
80 ttm_debugfs_root = debugfs_create_dir("ttm", NULL);
81 if (IS_ERR(ttm_debugfs_root)) {
82 ttm_debugfs_root = NULL;
83 }
84
85 /* Limit the number of pages in the pool to about 50% of the total
86 * system memory.
87 */
88 num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
89 num_pages /= 2;
90
91 /* But for DMA32 we limit ourself to only use 2GiB maximum. */
92 num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
93 >> PAGE_SHIFT;
94 num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
95
96 ttm_pool_mgr_init(num_pages);
97 ttm_tt_mgr_init(num_pages, num_dma32);
98
99 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
100 __GFP_NOWARN);
101
102 /* Retry without GFP_DMA32 for platforms DMA32 is not available */
103 if (unlikely(glob->dummy_read_page == NULL)) {
104 glob->dummy_read_page = alloc_page(__GFP_ZERO);
105 if (unlikely(glob->dummy_read_page == NULL)) {
106 ret = -ENOMEM;
107 goto out;
108 }
109 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
110 }
111
112 INIT_LIST_HEAD(&glob->device_list);
113 atomic_set(&glob->bo_count, 0);
114
115 debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root,
116 &glob->bo_count);
117 out:
118 if (ret && ttm_debugfs_root)
119 debugfs_remove(ttm_debugfs_root);
120 if (ret)
121 --ttm_glob_use_count;
122 mutex_unlock(&ttm_global_mutex);
123 return ret;
124 }
125
126 /*
127 * A buffer object shrink method that tries to swap out the first
128 * buffer object on the global::swap_lru list.
129 */
ttm_global_swapout(struct ttm_operation_ctx * ctx,gfp_t gfp_flags)130 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
131 {
132 struct ttm_global *glob = &ttm_glob;
133 struct ttm_device *bdev;
134 int ret = 0;
135
136 mutex_lock(&ttm_global_mutex);
137 list_for_each_entry(bdev, &glob->device_list, device_list) {
138 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
139 if (ret > 0) {
140 list_move_tail(&bdev->device_list, &glob->device_list);
141 break;
142 }
143 }
144 mutex_unlock(&ttm_global_mutex);
145 return ret;
146 }
147
ttm_device_swapout(struct ttm_device * bdev,struct ttm_operation_ctx * ctx,gfp_t gfp_flags)148 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
149 gfp_t gfp_flags)
150 {
151 struct ttm_resource_manager *man;
152 unsigned i;
153 s64 lret;
154
155 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
156 man = ttm_manager_type(bdev, i);
157 if (!man || !man->use_tt)
158 continue;
159
160 lret = ttm_bo_swapout(bdev, ctx, man, gfp_flags, 1);
161 /* Can be both positive (num_pages) and negative (error) */
162 if (lret)
163 return lret;
164 }
165 return 0;
166 }
167 EXPORT_SYMBOL(ttm_device_swapout);
168
169 /**
170 * ttm_device_init
171 *
172 * @bdev: A pointer to a struct ttm_device to initialize.
173 * @funcs: Function table for the device.
174 * @dev: The core kernel device pointer for DMA mappings and allocations.
175 * @mapping: The address space to use for this bo.
176 * @vma_manager: A pointer to a vma manager.
177 * @use_dma_alloc: If coherent DMA allocation API should be used.
178 * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
179 *
180 * Initializes a struct ttm_device:
181 * Returns:
182 * !0: Failure.
183 */
ttm_device_init(struct ttm_device * bdev,const struct ttm_device_funcs * funcs,struct device * dev,struct address_space * mapping,struct drm_vma_offset_manager * vma_manager,bool use_dma_alloc,bool use_dma32)184 int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
185 struct device *dev, struct address_space *mapping,
186 struct drm_vma_offset_manager *vma_manager,
187 bool use_dma_alloc, bool use_dma32)
188 {
189 struct ttm_global *glob = &ttm_glob;
190 int ret, nid;
191
192 if (WARN_ON(vma_manager == NULL))
193 return -EINVAL;
194
195 ret = ttm_global_init();
196 if (ret)
197 return ret;
198
199 bdev->wq = alloc_workqueue("ttm",
200 WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16);
201 if (!bdev->wq) {
202 ttm_global_release();
203 return -ENOMEM;
204 }
205
206 bdev->funcs = funcs;
207
208 ttm_sys_man_init(bdev);
209
210 if (dev)
211 nid = dev_to_node(dev);
212 else
213 nid = NUMA_NO_NODE;
214
215 ttm_pool_init(&bdev->pool, dev, nid, use_dma_alloc, use_dma32);
216
217 bdev->vma_manager = vma_manager;
218 spin_lock_init(&bdev->lru_lock);
219 INIT_LIST_HEAD(&bdev->pinned);
220 bdev->dev_mapping = mapping;
221 mutex_lock(&ttm_global_mutex);
222 list_add_tail(&bdev->device_list, &glob->device_list);
223 mutex_unlock(&ttm_global_mutex);
224
225 return 0;
226 }
227 EXPORT_SYMBOL(ttm_device_init);
228
ttm_device_fini(struct ttm_device * bdev)229 void ttm_device_fini(struct ttm_device *bdev)
230 {
231 struct ttm_resource_manager *man;
232 unsigned i;
233
234 mutex_lock(&ttm_global_mutex);
235 list_del(&bdev->device_list);
236 mutex_unlock(&ttm_global_mutex);
237
238 drain_workqueue(bdev->wq);
239 destroy_workqueue(bdev->wq);
240
241 man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
242 ttm_resource_manager_set_used(man, false);
243 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
244
245 spin_lock(&bdev->lru_lock);
246 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
247 if (list_empty(&man->lru[0]))
248 pr_debug("Swap list %d was clean\n", i);
249 spin_unlock(&bdev->lru_lock);
250
251 ttm_pool_fini(&bdev->pool);
252 ttm_global_release();
253 }
254 EXPORT_SYMBOL(ttm_device_fini);
255
ttm_device_clear_lru_dma_mappings(struct ttm_device * bdev,struct list_head * list)256 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
257 struct list_head *list)
258 {
259 struct ttm_resource *res;
260
261 spin_lock(&bdev->lru_lock);
262 while ((res = ttm_lru_first_res_or_null(list))) {
263 struct ttm_buffer_object *bo = res->bo;
264
265 /* Take ref against racing releases once lru_lock is unlocked */
266 if (!ttm_bo_get_unless_zero(bo))
267 continue;
268
269 list_del_init(&bo->resource->lru.link);
270 spin_unlock(&bdev->lru_lock);
271
272 if (bo->ttm)
273 ttm_tt_unpopulate(bo->bdev, bo->ttm);
274
275 ttm_bo_put(bo);
276 spin_lock(&bdev->lru_lock);
277 }
278 spin_unlock(&bdev->lru_lock);
279 }
280
ttm_device_clear_dma_mappings(struct ttm_device * bdev)281 void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
282 {
283 struct ttm_resource_manager *man;
284 unsigned int i, j;
285
286 ttm_device_clear_lru_dma_mappings(bdev, &bdev->pinned);
287
288 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
289 man = ttm_manager_type(bdev, i);
290 if (!man || !man->use_tt)
291 continue;
292
293 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
294 ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]);
295 }
296 }
297 EXPORT_SYMBOL(ttm_device_clear_dma_mappings);
298