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/export.h>
32#include <linux/mm.h>
33
34#include <drm/ttm/ttm_allocation.h>
35#include <drm/ttm/ttm_bo.h>
36#include <drm/ttm/ttm_device.h>
37#include <drm/ttm/ttm_tt.h>
38#include <drm/ttm/ttm_placement.h>
39
40#include "ttm_module.h"
41#include "ttm_bo_internal.h"
42
43/*
44 * ttm_global_mutex - protecting the global state
45 */
46static DEFINE_MUTEX(ttm_global_mutex);
47static unsigned ttm_glob_use_count;
48struct ttm_global ttm_glob;
49EXPORT_SYMBOL(ttm_glob);
50
51struct dentry *ttm_debugfs_root;
52
53static void ttm_global_release(void)
54{
55 struct ttm_global *glob = &ttm_glob;
56
57 mutex_lock(&ttm_global_mutex);
58 if (--ttm_glob_use_count > 0)
59 goto out;
60
61 ttm_pool_mgr_fini();
62 debugfs_remove(dentry: ttm_debugfs_root);
63
64 __free_page(glob->dummy_read_page);
65 memset(glob, 0, sizeof(*glob));
66out:
67 mutex_unlock(lock: &ttm_global_mutex);
68}
69
70static int ttm_global_init(void)
71{
72 struct ttm_global *glob = &ttm_glob;
73 unsigned long num_pages, num_dma32;
74 struct sysinfo si;
75 int ret = 0;
76
77 mutex_lock(&ttm_global_mutex);
78 if (++ttm_glob_use_count > 1)
79 goto out;
80
81 si_meminfo(val: &si);
82
83 ttm_debugfs_root = debugfs_create_dir(name: "ttm", NULL);
84 if (IS_ERR(ptr: ttm_debugfs_root)) {
85 ttm_debugfs_root = NULL;
86 }
87
88 /* Limit the number of pages in the pool to about 50% of the total
89 * system memory.
90 */
91 num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT;
92 num_pages /= 2;
93
94 /* But for DMA32 we limit ourself to only use 2GiB maximum. */
95 num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit
96 >> PAGE_SHIFT;
97 num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT));
98
99 ttm_pool_mgr_init(num_pages);
100 ttm_tt_mgr_init(num_pages, num_dma32_pages: num_dma32);
101
102 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 |
103 __GFP_NOWARN);
104
105 /* Retry without GFP_DMA32 for platforms DMA32 is not available */
106 if (unlikely(glob->dummy_read_page == NULL)) {
107 glob->dummy_read_page = alloc_page(__GFP_ZERO);
108 if (unlikely(glob->dummy_read_page == NULL)) {
109 ret = -ENOMEM;
110 goto out;
111 }
112 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n");
113 }
114
115 INIT_LIST_HEAD(list: &glob->device_list);
116 atomic_set(v: &glob->bo_count, i: 0);
117
118 debugfs_create_atomic_t(name: "buffer_objects", mode: 0444, parent: ttm_debugfs_root,
119 value: &glob->bo_count);
120out:
121 if (ret && ttm_debugfs_root)
122 debugfs_remove(dentry: ttm_debugfs_root);
123 if (ret)
124 --ttm_glob_use_count;
125 mutex_unlock(lock: &ttm_global_mutex);
126 return ret;
127}
128
129/**
130 * ttm_device_prepare_hibernation - move GTT BOs to shmem for hibernation.
131 *
132 * @bdev: A pointer to a struct ttm_device to prepare hibernation for.
133 *
134 * Return: 0 on success, negative number on failure.
135 */
136int ttm_device_prepare_hibernation(struct ttm_device *bdev)
137{
138 struct ttm_operation_ctx ctx = {
139 .interruptible = false,
140 .no_wait_gpu = false,
141 };
142 int ret;
143
144 do {
145 ret = ttm_device_swapout(bdev, ctx: &ctx, GFP_KERNEL);
146 } while (ret > 0);
147 return ret;
148}
149EXPORT_SYMBOL(ttm_device_prepare_hibernation);
150
151/*
152 * A buffer object shrink method that tries to swap out the first
153 * buffer object on the global::swap_lru list.
154 */
155int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags)
156{
157 struct ttm_global *glob = &ttm_glob;
158 struct ttm_device *bdev;
159 int ret = 0;
160
161 mutex_lock(&ttm_global_mutex);
162 list_for_each_entry(bdev, &glob->device_list, device_list) {
163 ret = ttm_device_swapout(bdev, ctx, gfp_flags);
164 if (ret > 0) {
165 list_move_tail(list: &bdev->device_list, head: &glob->device_list);
166 break;
167 }
168 }
169 mutex_unlock(lock: &ttm_global_mutex);
170 return ret;
171}
172
173int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx,
174 gfp_t gfp_flags)
175{
176 struct ttm_resource_manager *man;
177 unsigned i;
178 s64 lret;
179
180 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
181 man = ttm_manager_type(bdev, mem_type: i);
182 if (!man || !man->use_tt)
183 continue;
184
185 lret = ttm_bo_swapout(bdev, ctx, man, gfp_flags, target: 1);
186 /* Can be both positive (num_pages) and negative (error) */
187 if (lret)
188 return lret;
189 }
190 return 0;
191}
192EXPORT_SYMBOL(ttm_device_swapout);
193
194/**
195 * ttm_device_init
196 *
197 * @bdev: A pointer to a struct ttm_device to initialize.
198 * @funcs: Function table for the device.
199 * @dev: The core kernel device pointer for DMA mappings and allocations.
200 * @mapping: The address space to use for this bo.
201 * @vma_manager: A pointer to a vma manager.
202 * @alloc_flags: TTM_ALLOCATION_* flags.
203 *
204 * Initializes a struct ttm_device:
205 * Returns:
206 * !0: Failure.
207 */
208int ttm_device_init(struct ttm_device *bdev, const struct ttm_device_funcs *funcs,
209 struct device *dev, struct address_space *mapping,
210 struct drm_vma_offset_manager *vma_manager,
211 unsigned int alloc_flags)
212{
213 struct ttm_global *glob = &ttm_glob;
214 int ret, nid;
215
216 if (WARN_ON(vma_manager == NULL))
217 return -EINVAL;
218
219 ret = ttm_global_init();
220 if (ret)
221 return ret;
222
223 bdev->wq = alloc_workqueue("ttm",
224 WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 16);
225 if (!bdev->wq) {
226 ttm_global_release();
227 return -ENOMEM;
228 }
229
230 bdev->alloc_flags = alloc_flags;
231 bdev->funcs = funcs;
232
233 ttm_sys_man_init(bdev);
234
235 if (dev)
236 nid = dev_to_node(dev);
237 else
238 nid = NUMA_NO_NODE;
239
240 ttm_pool_init(pool: &bdev->pool, dev, nid, alloc_flags);
241
242 bdev->vma_manager = vma_manager;
243 spin_lock_init(&bdev->lru_lock);
244 INIT_LIST_HEAD(list: &bdev->unevictable);
245 bdev->dev_mapping = mapping;
246 mutex_lock(&ttm_global_mutex);
247 list_add_tail(new: &bdev->device_list, head: &glob->device_list);
248 mutex_unlock(lock: &ttm_global_mutex);
249
250 return 0;
251}
252EXPORT_SYMBOL(ttm_device_init);
253
254void ttm_device_fini(struct ttm_device *bdev)
255{
256 struct ttm_resource_manager *man;
257 unsigned i;
258
259 mutex_lock(&ttm_global_mutex);
260 list_del(entry: &bdev->device_list);
261 mutex_unlock(lock: &ttm_global_mutex);
262
263 drain_workqueue(wq: bdev->wq);
264 destroy_workqueue(wq: bdev->wq);
265
266 man = ttm_manager_type(bdev, TTM_PL_SYSTEM);
267 ttm_resource_manager_set_used(man, used: false);
268 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL);
269
270 spin_lock(lock: &bdev->lru_lock);
271 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i)
272 if (list_empty(head: &man->lru[0]))
273 pr_debug("Swap list %d was clean\n", i);
274 spin_unlock(lock: &bdev->lru_lock);
275
276 ttm_pool_fini(pool: &bdev->pool);
277 ttm_global_release();
278}
279EXPORT_SYMBOL(ttm_device_fini);
280
281static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev,
282 struct list_head *list)
283{
284 struct ttm_resource *res;
285
286 spin_lock(lock: &bdev->lru_lock);
287 while ((res = ttm_lru_first_res_or_null(head: list))) {
288 struct ttm_buffer_object *bo = res->bo;
289
290 /* Take ref against racing releases once lru_lock is unlocked */
291 if (!ttm_bo_get_unless_zero(bo))
292 continue;
293
294 list_del_init(entry: &bo->resource->lru.link);
295 spin_unlock(lock: &bdev->lru_lock);
296
297 if (bo->ttm)
298 ttm_tt_unpopulate(bdev: bo->bdev, ttm: bo->ttm);
299
300 ttm_bo_put(bo);
301 spin_lock(lock: &bdev->lru_lock);
302 }
303 spin_unlock(lock: &bdev->lru_lock);
304}
305
306void ttm_device_clear_dma_mappings(struct ttm_device *bdev)
307{
308 struct ttm_resource_manager *man;
309 unsigned int i, j;
310
311 ttm_device_clear_lru_dma_mappings(bdev, list: &bdev->unevictable);
312
313 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) {
314 man = ttm_manager_type(bdev, mem_type: i);
315 if (!man || !man->use_tt)
316 continue;
317
318 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j)
319 ttm_device_clear_lru_dma_mappings(bdev, list: &man->lru[j]);
320 }
321}
322EXPORT_SYMBOL(ttm_device_clear_dma_mappings);
323

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