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 __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(&glob->device_list); 112 atomic_set(&glob->bo_count, 0); 113 114 debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root, 115 &glob->bo_count); 116 out: 117 if (ret && ttm_debugfs_root) 118 debugfs_remove(ttm_debugfs_root); 119 if (ret) 120 --ttm_glob_use_count; 121 mutex_unlock(&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 */ 129 int 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(&bdev->device_list, &glob->device_list); 140 break; 141 } 142 } 143 mutex_unlock(&ttm_global_mutex); 144 return ret; 145 } 146 147 int 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(&bdev->lru_lock); 157 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 158 man = ttm_manager_type(bdev, 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(&bdev->lru_lock); 179 return 0; 180 } 181 EXPORT_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 */ 198 int 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("ttm", 214 WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_UNBOUND, 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(&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(&bdev->pinned); 234 bdev->dev_mapping = mapping; 235 mutex_lock(&ttm_global_mutex); 236 list_add_tail(&bdev->device_list, &glob->device_list); 237 mutex_unlock(&ttm_global_mutex); 238 239 return 0; 240 } 241 EXPORT_SYMBOL(ttm_device_init); 242 243 void 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(&bdev->device_list); 250 mutex_unlock(&ttm_global_mutex); 251 252 drain_workqueue(bdev->wq); 253 destroy_workqueue(bdev->wq); 254 255 man = ttm_manager_type(bdev, TTM_PL_SYSTEM); 256 ttm_resource_manager_set_used(man, false); 257 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL); 258 259 spin_lock(&bdev->lru_lock); 260 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) 261 if (list_empty(&man->lru[0])) 262 pr_debug("Swap list %d was clean\n", i); 263 spin_unlock(&bdev->lru_lock); 264 265 ttm_pool_fini(&bdev->pool); 266 ttm_global_release(); 267 } 268 EXPORT_SYMBOL(ttm_device_fini); 269 270 static 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(&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(&res->lru); 284 spin_unlock(&bdev->lru_lock); 285 286 if (bo->ttm) 287 ttm_tt_unpopulate(bo->bdev, bo->ttm); 288 289 ttm_bo_put(bo); 290 spin_lock(&bdev->lru_lock); 291 } 292 spin_unlock(&bdev->lru_lock); 293 } 294 295 void 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, &bdev->pinned); 301 302 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 303 man = ttm_manager_type(bdev, 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, &man->lru[j]); 309 } 310 } 311 EXPORT_SYMBOL(ttm_device_clear_dma_mappings); 312