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_bo.h> 35 #include <drm/ttm/ttm_device.h> 36 #include <drm/ttm/ttm_tt.h> 37 #include <drm/ttm/ttm_placement.h> 38 39 #include "ttm_module.h" 40 #include "ttm_bo_internal.h" 41 42 /* 43 * ttm_global_mutex - protecting the global state 44 */ 45 static DEFINE_MUTEX(ttm_global_mutex); 46 static unsigned ttm_glob_use_count; 47 struct ttm_global ttm_glob; 48 EXPORT_SYMBOL(ttm_glob); 49 50 struct dentry *ttm_debugfs_root; 51 52 static void ttm_global_release(void) 53 { 54 struct ttm_global *glob = &ttm_glob; 55 56 mutex_lock(&ttm_global_mutex); 57 if (--ttm_glob_use_count > 0) 58 goto out; 59 60 ttm_pool_mgr_fini(); 61 debugfs_remove(ttm_debugfs_root); 62 63 __free_page(glob->dummy_read_page); 64 memset(glob, 0, sizeof(*glob)); 65 out: 66 mutex_unlock(&ttm_global_mutex); 67 } 68 69 static int ttm_global_init(void) 70 { 71 struct ttm_global *glob = &ttm_glob; 72 unsigned long num_pages, num_dma32; 73 struct sysinfo si; 74 int ret = 0; 75 76 mutex_lock(&ttm_global_mutex); 77 if (++ttm_glob_use_count > 1) 78 goto out; 79 80 si_meminfo(&si); 81 82 ttm_debugfs_root = debugfs_create_dir("ttm", NULL); 83 if (IS_ERR(ttm_debugfs_root)) { 84 ttm_debugfs_root = NULL; 85 } 86 87 /* Limit the number of pages in the pool to about 50% of the total 88 * system memory. 89 */ 90 num_pages = ((u64)si.totalram * si.mem_unit) >> PAGE_SHIFT; 91 num_pages /= 2; 92 93 /* But for DMA32 we limit ourself to only use 2GiB maximum. */ 94 num_dma32 = (u64)(si.totalram - si.totalhigh) * si.mem_unit 95 >> PAGE_SHIFT; 96 num_dma32 = min(num_dma32, 2UL << (30 - PAGE_SHIFT)); 97 98 ttm_pool_mgr_init(num_pages); 99 ttm_tt_mgr_init(num_pages, num_dma32); 100 101 glob->dummy_read_page = alloc_page(__GFP_ZERO | GFP_DMA32 | 102 __GFP_NOWARN); 103 104 /* Retry without GFP_DMA32 for platforms DMA32 is not available */ 105 if (unlikely(glob->dummy_read_page == NULL)) { 106 glob->dummy_read_page = alloc_page(__GFP_ZERO); 107 if (unlikely(glob->dummy_read_page == NULL)) { 108 ret = -ENOMEM; 109 goto out; 110 } 111 pr_warn("Using GFP_DMA32 fallback for dummy_read_page\n"); 112 } 113 114 INIT_LIST_HEAD(&glob->device_list); 115 atomic_set(&glob->bo_count, 0); 116 117 debugfs_create_atomic_t("buffer_objects", 0444, ttm_debugfs_root, 118 &glob->bo_count); 119 out: 120 if (ret && ttm_debugfs_root) 121 debugfs_remove(ttm_debugfs_root); 122 if (ret) 123 --ttm_glob_use_count; 124 mutex_unlock(&ttm_global_mutex); 125 return ret; 126 } 127 128 /** 129 * ttm_device_prepare_hibernation - move GTT BOs to shmem for hibernation. 130 * 131 * @bdev: A pointer to a struct ttm_device to prepare hibernation for. 132 * 133 * Return: 0 on success, negative number on failure. 134 */ 135 int ttm_device_prepare_hibernation(struct ttm_device *bdev) 136 { 137 struct ttm_operation_ctx ctx = { 138 .interruptible = false, 139 .no_wait_gpu = false, 140 }; 141 int ret; 142 143 do { 144 ret = ttm_device_swapout(bdev, &ctx, GFP_KERNEL); 145 } while (ret > 0); 146 return ret; 147 } 148 EXPORT_SYMBOL(ttm_device_prepare_hibernation); 149 150 /* 151 * A buffer object shrink method that tries to swap out the first 152 * buffer object on the global::swap_lru list. 153 */ 154 int ttm_global_swapout(struct ttm_operation_ctx *ctx, gfp_t gfp_flags) 155 { 156 struct ttm_global *glob = &ttm_glob; 157 struct ttm_device *bdev; 158 int ret = 0; 159 160 mutex_lock(&ttm_global_mutex); 161 list_for_each_entry(bdev, &glob->device_list, device_list) { 162 ret = ttm_device_swapout(bdev, ctx, gfp_flags); 163 if (ret > 0) { 164 list_move_tail(&bdev->device_list, &glob->device_list); 165 break; 166 } 167 } 168 mutex_unlock(&ttm_global_mutex); 169 return ret; 170 } 171 172 int ttm_device_swapout(struct ttm_device *bdev, struct ttm_operation_ctx *ctx, 173 gfp_t gfp_flags) 174 { 175 struct ttm_resource_manager *man; 176 unsigned i; 177 s64 lret; 178 179 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 180 man = ttm_manager_type(bdev, i); 181 if (!man || !man->use_tt) 182 continue; 183 184 lret = ttm_bo_swapout(bdev, ctx, man, gfp_flags, 1); 185 /* Can be both positive (num_pages) and negative (error) */ 186 if (lret) 187 return lret; 188 } 189 return 0; 190 } 191 EXPORT_SYMBOL(ttm_device_swapout); 192 193 /** 194 * ttm_device_init 195 * 196 * @bdev: A pointer to a struct ttm_device to initialize. 197 * @funcs: Function table for the device. 198 * @dev: The core kernel device pointer for DMA mappings and allocations. 199 * @mapping: The address space to use for this bo. 200 * @vma_manager: A pointer to a vma manager. 201 * @use_dma_alloc: If coherent DMA allocation API should be used. 202 * @use_dma32: If we should use GFP_DMA32 for device memory allocations. 203 * 204 * Initializes a struct ttm_device: 205 * Returns: 206 * !0: Failure. 207 */ 208 int 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 bool use_dma_alloc, bool use_dma32) 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->funcs = funcs; 231 232 ttm_sys_man_init(bdev); 233 234 if (dev) 235 nid = dev_to_node(dev); 236 else 237 nid = NUMA_NO_NODE; 238 239 ttm_pool_init(&bdev->pool, dev, nid, use_dma_alloc, use_dma32); 240 241 bdev->vma_manager = vma_manager; 242 spin_lock_init(&bdev->lru_lock); 243 INIT_LIST_HEAD(&bdev->unevictable); 244 bdev->dev_mapping = mapping; 245 mutex_lock(&ttm_global_mutex); 246 list_add_tail(&bdev->device_list, &glob->device_list); 247 mutex_unlock(&ttm_global_mutex); 248 249 return 0; 250 } 251 EXPORT_SYMBOL(ttm_device_init); 252 253 void ttm_device_fini(struct ttm_device *bdev) 254 { 255 struct ttm_resource_manager *man; 256 unsigned i; 257 258 mutex_lock(&ttm_global_mutex); 259 list_del(&bdev->device_list); 260 mutex_unlock(&ttm_global_mutex); 261 262 drain_workqueue(bdev->wq); 263 destroy_workqueue(bdev->wq); 264 265 man = ttm_manager_type(bdev, TTM_PL_SYSTEM); 266 ttm_resource_manager_set_used(man, false); 267 ttm_set_driver_manager(bdev, TTM_PL_SYSTEM, NULL); 268 269 spin_lock(&bdev->lru_lock); 270 for (i = 0; i < TTM_MAX_BO_PRIORITY; ++i) 271 if (list_empty(&man->lru[0])) 272 pr_debug("Swap list %d was clean\n", i); 273 spin_unlock(&bdev->lru_lock); 274 275 ttm_pool_fini(&bdev->pool); 276 ttm_global_release(); 277 } 278 EXPORT_SYMBOL(ttm_device_fini); 279 280 static void ttm_device_clear_lru_dma_mappings(struct ttm_device *bdev, 281 struct list_head *list) 282 { 283 struct ttm_resource *res; 284 285 spin_lock(&bdev->lru_lock); 286 while ((res = ttm_lru_first_res_or_null(list))) { 287 struct ttm_buffer_object *bo = res->bo; 288 289 /* Take ref against racing releases once lru_lock is unlocked */ 290 if (!ttm_bo_get_unless_zero(bo)) 291 continue; 292 293 list_del_init(&bo->resource->lru.link); 294 spin_unlock(&bdev->lru_lock); 295 296 if (bo->ttm) 297 ttm_tt_unpopulate(bo->bdev, bo->ttm); 298 299 ttm_bo_put(bo); 300 spin_lock(&bdev->lru_lock); 301 } 302 spin_unlock(&bdev->lru_lock); 303 } 304 305 void ttm_device_clear_dma_mappings(struct ttm_device *bdev) 306 { 307 struct ttm_resource_manager *man; 308 unsigned int i, j; 309 310 ttm_device_clear_lru_dma_mappings(bdev, &bdev->unevictable); 311 312 for (i = TTM_PL_SYSTEM; i < TTM_NUM_MEM_TYPES; ++i) { 313 man = ttm_manager_type(bdev, i); 314 if (!man || !man->use_tt) 315 continue; 316 317 for (j = 0; j < TTM_MAX_BO_PRIORITY; ++j) 318 ttm_device_clear_lru_dma_mappings(bdev, &man->lru[j]); 319 } 320 } 321 EXPORT_SYMBOL(ttm_device_clear_dma_mappings); 322