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 */ 42 static DEFINE_MUTEX(ttm_global_mutex); 43 static unsigned ttm_glob_use_count; 44 struct ttm_global ttm_glob; 45 EXPORT_SYMBOL(ttm_glob); 46 47 struct dentry *ttm_debugfs_root; 48 49 static 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(ttm_debugfs_root); 59 60 __free_page(glob->dummy_read_page); 61 memset(glob, 0, sizeof(*glob)); 62 out: 63 mutex_unlock(&ttm_global_mutex); 64 } 65 66 static 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(&si); 78 79 ttm_debugfs_root = debugfs_create_dir("ttm", NULL); 80 if (IS_ERR(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); 97 98 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32); 99 100 if (unlikely(glob->dummy_read_page == NULL)) { 101 ret = -ENOMEM; 102 goto out; 103 } 104 105 INIT_LIST_HEAD(&glob->device_list); 106 atomic_set(&glob->bo_count, 0); 107 108 debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root, 109 &glob->bo_count); 110 out: 111 if (ret && ttm_debugfs_root) 112 debugfs_remove(ttm_debugfs_root); 113 if (ret) 114 --ttm_glob_use_count; 115 mutex_unlock(&ttm_global_mutex); 116 return ret; 117 } 118 119 /* 120 * A buffer object shrink method that tries to swap out the first 121 * buffer object on the global::swap_lru list. 122 */ 123 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags) 124 { 125 struct ttm_global *glob = &ttm_glob; 126 struct ttm_device *bdev; 127 int ret = 0; 128 129 mutex_lock(&ttm_global_mutex); 130 list_for_each_entry(bdev, &glob->device_list, device_list) { 131 ret = ttm_device_swapout(bdev, ctx, gfp_flags); 132 if (ret > 0) { 133 list_move_tail(&bdev->device_list, &glob->device_list); 134 break; 135 } 136 } 137 mutex_unlock(&ttm_global_mutex); 138 return ret; 139 } 140 141 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx, 142 gfp_t gfp_flags) 143 { 144 struct ttm_resource_cursor cursor; 145 struct ttm_resource_manager *man; 146 struct ttm_resource *res; 147 unsigned i; 148 int ret; 149 150 spin_lock(&bdev->lru_lock); 151 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 152 man = ttm_manager_type(bdev, i); 153 if (!man || !man->use_tt) 154 continue; 155 156 ttm_resource_manager_for_each_res(man, &cursor, res) { 157 struct ttm_buffer_object *bo = res->bo; 158 uint32_t num_pages; 159 160 if (!bo || bo->resource != res) 161 continue; 162 163 num_pages = PFN_UP(bo->base.size); 164 ret = ttm_bo_swapout(bo, ctx, gfp_flags); 165 /* ttm_bo_swapout has dropped the lru_lock */ 166 if (!ret) 167 return num_pages; 168 if (ret != -EBUSY) 169 return ret; 170 } 171 } 172 spin_unlock(&bdev->lru_lock); 173 return 0; 174 } 175 EXPORT_SYMBOL(ttm_device_swapout); 176 177 /** 178 * ttm_device_init 179 * 180 * @bdev: A pointer to a struct ttm_device to initialize. 181 * @funcs: Function table for the device. 182 * @dev: The core kernel device pointer for DMA mappings and allocations. 183 * @mapping: The address space to use for this bo. 184 * @vma_manager: A pointer to a vma manager. 185 * @use_dma_alloc: If coherent DMA allocation API should be used. 186 * @use_dma32: If we should use GFP_DMA32 for device memory allocations. 187 * 188 * Initializes a struct ttm_device: 189 * Returns: 190 * !0: Failure. 191 */ 192 int ttm_device_init(struct ttm_device *bdev, struct ttm_device_funcs *funcs, 193 struct device *dev, struct address_space *mapping, 194 struct drm_vma_offset_manager *vma_manager, 195 bool use_dma_alloc, bool use_dma32) 196 { 197 struct ttm_global *glob = &ttm_glob; 198 int ret; 199 200 if (WARN_ON(vma_manager == NULL)) 201 return -EINVAL; 202 203 ret = ttm_global_init(); 204 if (ret) 205 return ret; 206 207 bdev->wq = alloc_workqueue("ttm", WQ_MEM_RECLAIM | WQ_HIGHPRI, 16); 208 if (!bdev->wq) { 209 ttm_global_release(); 210 return -ENOMEM; 211 } 212 213 bdev->funcs = funcs; 214 215 ttm_sys_man_init(bdev); 216 ttm_pool_init(&bdev->pool, dev, use_dma_alloc, use_dma32); 217 218 bdev->vma_manager = vma_manager; 219 spin_lock_init(&bdev->lru_lock); 220 INIT_LIST_HEAD(&bdev->pinned); 221 bdev->dev_mapping = mapping; 222 mutex_lock(&ttm_global_mutex); 223 list_add_tail(&bdev->device_list, &glob->device_list); 224 mutex_unlock(&ttm_global_mutex); 225 226 return 0; 227 } 228 EXPORT_SYMBOL(ttm_device_init); 229 230 void ttm_device_fini(struct ttm_device *bdev) 231 { 232 struct ttm_resource_manager *man; 233 unsigned i; 234 235 man = ttm_manager_type(bdev, TTM_PL_SYSTEM); 236 ttm_resource_manager_set_used(man, false); 237 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL); 238 239 mutex_lock(&ttm_global_mutex); 240 list_del(&bdev->device_list); 241 mutex_unlock(&ttm_global_mutex); 242 243 drain_workqueue(bdev->wq); 244 destroy_workqueue(bdev->wq); 245 246 spin_lock(&bdev->lru_lock); 247 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) 248 if (list_empty(&man->lru[0])) 249 pr_debug("Swap list %d was clean\n", i); 250 spin_unlock(&bdev->lru_lock); 251 252 ttm_pool_fini(&bdev->pool); 253 ttm_global_release(); 254 } 255 EXPORT_SYMBOL(ttm_device_fini); 256 257 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev, 258 struct list_head *list) 259 { 260 struct ttm_resource *res; 261 262 spin_lock(&bdev->lru_lock); 263 while ((res = list_first_entry_or_null(list, typeof(*res), lru))) { 264 struct ttm_buffer_object *bo = res->bo; 265 266 /* Take ref against racing releases once lru_lock is unlocked */ 267 if (!ttm_bo_get_unless_zero(bo)) 268 continue; 269 270 list_del_init(&res->lru); 271 spin_unlock(&bdev->lru_lock); 272 273 if (bo->ttm) 274 ttm_tt_unpopulate(bo->bdev, bo->ttm); 275 276 ttm_bo_put(bo); 277 spin_lock(&bdev->lru_lock); 278 } 279 spin_unlock(&bdev->lru_lock); 280 } 281 282 void ttm_device_clear_dma_mappings(struct ttm_device *bdev) 283 { 284 struct ttm_resource_manager *man; 285 unsigned int i, j; 286 287 ttm_device_clear_lru_dma_mappings(bdev, &bdev->pinned); 288 289 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 290 man = ttm_manager_type(bdev, i); 291 if (!man || !man->use_tt) 292 continue; 293 294 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) 295 ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]); 296 } 297 } 298 EXPORT_SYMBOL(ttm_device_clear_dma_mappings); 299