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/mm.h>
31
32#include <drm/ttm/ttm_bo.h>
33#include <drm/ttm/ttm_device.h>
34#include <drm/ttm/ttm_tt.h>
35#include <drm/ttm/ttm_placement.h>
36
37#include "ttm_module.h"
38
39/*
40 * ttm_global_mutex - protecting the global state
41 */
42static DEFINE_MUTEX(ttm_global_mutex);
43static unsigned ttm_glob_use_count;
44struct ttm_global ttm_glob;
45EXPORT_SYMBOL(ttm_glob);
46
47struct dentry *ttm_debugfs_root;
48
49static void ttm_global_release(void)
50{
51 struct ttm_global *glob = &ttm_glob;
52
53 mutex_lock(&ttm_global_mutex);
54 if (--ttm_glob_use_count > 0)
55 goto out;
56
57 ttm_pool_mgr_fini();
58 debugfs_remove(dentry: ttm_debugfs_root);
59
60 __free_page(glob->dummy_read_page);
61 memset(glob, 0, sizeof(*glob));
62out:
63 mutex_unlock(lock: &ttm_global_mutex);
64}
65
66static int ttm_global_init(void)
67{
68 struct ttm_global *glob = &ttm_glob;
69 unsigned long num_pages, num_dma32;
70 struct sysinfo si;
71 int ret = 0;
72
73 mutex_lock(&ttm_global_mutex);
74 if (++ttm_glob_use_count > 1)
75 goto out;
76
77 si_meminfo(val: &si);
78
79 ttm_debugfs_root = debugfs_create_dir(name: "ttm", NULL);
80 if (IS_ERR(ptr: ttm_debugfs_root)) {
81 ttm_debugfs_root = NULL;
82 }
83
84 /* Limit the number of pages in the pool to about 50% of the total
85 * system memory.
86 */
87 num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
88 num_pages /= 2;
89
90 /* But for DMA32 we limit ourself to only use 2GiB maximum. */
91 num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
92 >> PAGE_SHIFT;
93 num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
94
95 ttm_pool_mgr_init(num_pages);
96 ttm_tt_mgr_init(num_pages, num_dma32_pages: num_dma32);
97
98 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
99 __GFP_NOWARN);
100
101 /* Retry without GFP_DMA32 for platforms DMA32 is not available */
102 if (unlikely(glob->dummy_read_page == NULL)) {
103 glob->dummy_read_page = alloc_page(__GFP_ZERO);
104 if (unlikely(glob->dummy_read_page == NULL)) {
105 ret = -ENOMEM;
106 goto out;
107 }
108 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
109 }
110
111 INIT_LIST_HEAD(list: &glob->device_list);
112 atomic_set(v: &glob->bo_count, i: 0);
113
114 debugfs_create_atomic_t(name: "buffer_objects", mode: 0444, parent: ttm_debugfs_root,
115 value: &glob->bo_count);
116out:
117 if (ret && ttm_debugfs_root)
118 debugfs_remove(dentry: ttm_debugfs_root);
119 if (ret)
120 --ttm_glob_use_count;
121 mutex_unlock(lock: &ttm_global_mutex);
122 return ret;
123}
124
125/*
126 * A buffer object shrink method that tries to swap out the first
127 * buffer object on the global::swap_lru list.
128 */
129int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
130{
131 struct ttm_global *glob = &ttm_glob;
132 struct ttm_device *bdev;
133 int ret = 0;
134
135 mutex_lock(&ttm_global_mutex);
136 list_for_each_entry(bdev, &glob->device_list, device_list) {
137 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
138 if (ret > 0) {
139 list_move_tail(list: &bdev->device_list, head: &glob->device_list);
140 break;
141 }
142 }
143 mutex_unlock(lock: &ttm_global_mutex);
144 return ret;
145}
146
147int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
148 gfp_t gfp_flags)
149{
150 struct ttm_resource_cursor cursor;
151 struct ttm_resource_manager *man;
152 struct ttm_resource *res;
153 unsigned i;
154 int ret;
155
156 spin_lock(lock: &bdev->lru_lock);
157 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
158 man = ttm_manager_type(bdev, mem_type: i);
159 if (!man || !man->use_tt)
160 continue;
161
162 ttm_resource_manager_for_each_res(man, &cursor, res) {
163 struct ttm_buffer_object *bo = res->bo;
164 uint32_t num_pages;
165
166 if (!bo || bo->resource != res)
167 continue;
168
169 num_pages = PFN_UP(bo->base.size);
170 ret = ttm_bo_swapout(bo, ctx, gfp_flags);
171 /* ttm_bo_swapout has dropped the lru_lock */
172 if (!ret)
173 return num_pages;
174 if (ret != -EBUSY)
175 return ret;
176 }
177 }
178 spin_unlock(lock: &bdev->lru_lock);
179 return 0;
180}
181EXPORT_SYMBOL(ttm_device_swapout);
182
183/**
184 * ttm_device_init
185 *
186 * @bdev: A pointer to a struct ttm_device to initialize.
187 * @funcs: Function table for the device.
188 * @dev: The core kernel device pointer for DMA mappings and allocations.
189 * @mapping: The address space to use for this bo.
190 * @vma_manager: A pointer to a vma manager.
191 * @use_dma_alloc: If coherent DMA allocation API should be used.
192 * @use_dma32: If we should use GFP_DMA32 for device memory allocations.
193 *
194 * Initializes a struct ttm_device:
195 * Returns:
196 * !0: Failure.
197 */
198int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
199 struct device *dev, struct address_space *mapping,
200 struct drm_vma_offset_manager *vma_manager,
201 bool use_dma_alloc, bool use_dma32)
202{
203 struct ttm_global *glob = &ttm_glob;
204 int ret, nid;
205
206 if (WARN_ON(vma_manager == NULL))
207 return -EINVAL;
208
209 ret = ttm_global_init();
210 if (ret)
211 return ret;
212
213 bdev->wq = alloc_workqueue(fmt: "ttm",
214 flags: WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, max_active: 16);
215 if (!bdev->wq) {
216 ttm_global_release();
217 return -ENOMEM;
218 }
219
220 bdev->funcs = funcs;
221
222 ttm_sys_man_init(bdev);
223
224 if (dev)
225 nid = dev_to_node(dev);
226 else
227 nid = NUMA_NO_NODE;
228
229 ttm_pool_init(pool: &bdev->pool, dev, nid, use_dma_alloc, use_dma32);
230
231 bdev->vma_manager = vma_manager;
232 spin_lock_init(&bdev->lru_lock);
233 INIT_LIST_HEAD(list: &bdev->pinned);
234 bdev->dev_mapping = mapping;
235 mutex_lock(&ttm_global_mutex);
236 list_add_tail(new: &bdev->device_list, head: &glob->device_list);
237 mutex_unlock(lock: &ttm_global_mutex);
238
239 return 0;
240}
241EXPORT_SYMBOL(ttm_device_init);
242
243void ttm_device_fini(struct ttm_device *bdev)
244{
245 struct ttm_resource_manager *man;
246 unsigned i;
247
248 mutex_lock(&ttm_global_mutex);
249 list_del(entry: &bdev->device_list);
250 mutex_unlock(lock: &ttm_global_mutex);
251
252 drain_workqueue(wq: bdev->wq);
253 destroy_workqueue(wq: bdev->wq);
254
255 man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
256 ttm_resource_manager_set_used(man, used: false);
257 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
258
259 spin_lock(lock: &bdev->lru_lock);
260 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
261 if (list_empty(head: &man->lru[0]))
262 pr_debug("Swap list %d was clean\n", i);
263 spin_unlock(lock: &bdev->lru_lock);
264
265 ttm_pool_fini(pool: &bdev->pool);
266 ttm_global_release();
267}
268EXPORT_SYMBOL(ttm_device_fini);
269
270static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
271 struct list_head *list)
272{
273 struct ttm_resource *res;
274
275 spin_lock(lock: &bdev->lru_lock);
276 while ((res = list_first_entry_or_null(list, typeof(*res), lru))) {
277 struct ttm_buffer_object *bo = res->bo;
278
279 /* Take ref against racing releases once lru_lock is unlocked */
280 if (!ttm_bo_get_unless_zero(bo))
281 continue;
282
283 list_del_init(entry: &res->lru);
284 spin_unlock(lock: &bdev->lru_lock);
285
286 if (bo->ttm)
287 ttm_tt_unpopulate(bdev: bo->bdev, ttm: bo->ttm);
288
289 ttm_bo_put(bo);
290 spin_lock(lock: &bdev->lru_lock);
291 }
292 spin_unlock(lock: &bdev->lru_lock);
293}
294
295void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
296{
297 struct ttm_resource_manager *man;
298 unsigned int i, j;
299
300 ttm_device_clear_lru_dma_mappings(bdev, list: &bdev->pinned);
301
302 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
303 man = ttm_manager_type(bdev, mem_type: i);
304 if (!man || !man->use_tt)
305 continue;
306
307 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
308 ttm_device_clear_lru_dma_mappings(bdev, list: &man->lru[j]);
309 }
310}
311EXPORT_SYMBOL(ttm_device_clear_dma_mappings);
312

source code of linux/drivers/gpu/drm/ttm/ttm_device.c