1 /* SPDX-License-Identifier: GPL-2.0 OR MIT */ 2 /************************************************************************** 3 * 4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 5 * All Rights Reserved. 6 * 7 * Permission is hereby granted, free of charge, to any person obtaining a 8 * copy of this software and associated documentation files (the 9 * "Software"), to deal in the Software without restriction, including 10 * without limitation the rights to use, copy, modify, merge, publish, 11 * distribute, sub license, and/or sell copies of the Software, and to 12 * permit persons to whom the Software is furnished to do so, subject to 13 * the following conditions: 14 * 15 * The above copyright notice and this permission notice (including the 16 * next paragraph) shall be included in all copies or substantial portions 17 * of the Software. 18 * 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 25 * USE OR OTHER DEALINGS IN THE SOFTWARE. 26 * 27 **************************************************************************/ 28 /* 29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> 30 */ 31 32 #define pr_fmt(fmt) "[TTM] " fmt 33 34 #include <linux/sched.h> 35 #include <linux/shmem_fs.h> 36 #include <linux/file.h> 37 #include <linux/module.h> 38 #include <drm/drm_cache.h> 39 #include <drm/ttm/ttm_bo_driver.h> 40 41 #include "ttm_module.h" 42 43 static unsigned long ttm_pages_limit; 44 45 MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages"); 46 module_param_named(pages_limit, ttm_pages_limit, ulong, 0644); 47 48 static unsigned long ttm_dma32_pages_limit; 49 50 MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages"); 51 module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644); 52 53 static atomic_long_t ttm_pages_allocated; 54 static atomic_long_t ttm_dma32_pages_allocated; 55 56 /* 57 * Allocates a ttm structure for the given BO. 58 */ 59 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc) 60 { 61 struct ttm_device *bdev = bo->bdev; 62 uint32_t page_flags = 0; 63 64 dma_resv_assert_held(bo->base.resv); 65 66 if (bo->ttm) 67 return 0; 68 69 switch (bo->type) { 70 case ttm_bo_type_device: 71 if (zero_alloc) 72 page_flags |= TTM_TT_FLAG_ZERO_ALLOC; 73 break; 74 case ttm_bo_type_kernel: 75 break; 76 case ttm_bo_type_sg: 77 page_flags |= TTM_TT_FLAG_EXTERNAL; 78 break; 79 default: 80 pr_err("Illegal buffer object type\n"); 81 return -EINVAL; 82 } 83 84 bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags); 85 if (unlikely(bo->ttm == NULL)) 86 return -ENOMEM; 87 88 WARN_ON(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL_MAPPABLE && 89 !(bo->ttm->page_flags & TTM_TT_FLAG_EXTERNAL)); 90 91 return 0; 92 } 93 94 /* 95 * Allocates storage for pointers to the pages that back the ttm. 96 */ 97 static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm) 98 { 99 ttm->pages = kvcalloc(ttm->num_pages, sizeof(void*), GFP_KERNEL); 100 if (!ttm->pages) 101 return -ENOMEM; 102 ttm->orders = kvmalloc_array(ttm->num_pages, 103 sizeof(unsigned long), GFP_KERNEL | __GFP_ZERO); 104 if (!ttm->orders) 105 return -ENOMEM; 106 return 0; 107 } 108 109 static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm) 110 { 111 ttm->pages = kvcalloc(ttm->num_pages, sizeof(*ttm->pages) + 112 sizeof(*ttm->dma_address), GFP_KERNEL); 113 if (!ttm->pages) 114 return -ENOMEM; 115 116 ttm->dma_address = (void *)(ttm->pages + ttm->num_pages); 117 118 ttm->orders = kvmalloc_array(ttm->num_pages, 119 sizeof(unsigned long), 120 GFP_KERNEL | __GFP_ZERO); 121 if (!ttm->orders) 122 return -ENOMEM; 123 return 0; 124 } 125 126 static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm) 127 { 128 ttm->dma_address = kvcalloc(ttm->num_pages, sizeof(*ttm->dma_address), 129 GFP_KERNEL); 130 if (!ttm->dma_address) 131 return -ENOMEM; 132 133 return 0; 134 } 135 136 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm) 137 { 138 bdev->funcs->ttm_tt_destroy(bdev, ttm); 139 } 140 141 static void ttm_tt_init_fields(struct ttm_tt *ttm, 142 struct ttm_buffer_object *bo, 143 uint32_t page_flags, 144 enum ttm_caching caching, 145 unsigned long extra_pages) 146 { 147 ttm->num_pages = (PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT) + extra_pages; 148 ttm->caching = ttm_cached; 149 ttm->page_flags = page_flags; 150 ttm->dma_address = NULL; 151 ttm->swap_storage = NULL; 152 ttm->sg = bo->sg; 153 ttm->caching = caching; 154 } 155 156 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo, 157 uint32_t page_flags, enum ttm_caching caching, 158 unsigned long extra_pages) 159 { 160 ttm_tt_init_fields(ttm, bo, page_flags, caching, extra_pages); 161 162 if (ttm_tt_alloc_page_directory(ttm)) { 163 pr_err("Failed allocating page table\n"); 164 return -ENOMEM; 165 } 166 return 0; 167 } 168 EXPORT_SYMBOL(ttm_tt_init); 169 170 void ttm_tt_fini(struct ttm_tt *ttm) 171 { 172 WARN_ON(ttm->page_flags & TTM_TT_FLAG_PRIV_POPULATED); 173 174 if (ttm->swap_storage) 175 uao_detach(ttm->swap_storage); 176 ttm->swap_storage = NULL; 177 178 if (ttm->pages) 179 kvfree(ttm->pages); 180 else 181 kvfree(ttm->dma_address); 182 kvfree(ttm->orders); 183 ttm->pages = NULL; 184 ttm->dma_address = NULL; 185 ttm->orders = NULL; 186 187 bus_dmamap_destroy(ttm->dmat, ttm->map); 188 km_free(ttm->segs, round_page(ttm->num_pages * 189 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero); 190 } 191 EXPORT_SYMBOL(ttm_tt_fini); 192 193 int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo, 194 uint32_t page_flags, enum ttm_caching caching) 195 { 196 int ret; 197 int flags = BUS_DMA_WAITOK; 198 199 ttm_tt_init_fields(ttm, bo, page_flags, caching, 0); 200 201 if (page_flags & TTM_TT_FLAG_EXTERNAL) 202 ret = ttm_sg_tt_alloc_page_directory(ttm); 203 else 204 ret = ttm_dma_tt_alloc_page_directory(ttm); 205 if (ret) { 206 pr_err("Failed allocating page table\n"); 207 return -ENOMEM; 208 } 209 210 ttm->segs = km_alloc(round_page(ttm->num_pages * 211 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero, &kd_waitok); 212 213 ttm->dmat = bo->bdev->dmat; 214 215 if (bo->bdev->pool.use_dma32 == false) 216 flags |= BUS_DMA_64BIT; 217 if (bus_dmamap_create(ttm->dmat, ttm->num_pages << PAGE_SHIFT, 218 ttm->num_pages, ttm->num_pages << PAGE_SHIFT, 0, flags, 219 &ttm->map)) { 220 km_free(ttm->segs, round_page(ttm->num_pages * 221 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero); 222 if (ttm->pages) { 223 kvfree(ttm->pages); 224 kvfree(ttm->orders); 225 } else 226 kvfree(ttm->dma_address); 227 ttm->pages = NULL; 228 ttm->orders = NULL; 229 ttm->dma_address = NULL; 230 pr_err("Failed allocating page table\n"); 231 return -ENOMEM; 232 } 233 234 return 0; 235 } 236 EXPORT_SYMBOL(ttm_sg_tt_init); 237 238 int ttm_tt_swapin(struct ttm_tt *ttm) 239 { 240 struct uvm_object *swap_storage; 241 struct vm_page *from_page; 242 struct vm_page *to_page; 243 struct pglist plist; 244 int i, ret; 245 246 swap_storage = ttm->swap_storage; 247 BUG_ON(swap_storage == NULL); 248 249 TAILQ_INIT(&plist); 250 if (uvm_obj_wire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT, 251 &plist)) { 252 ret = -ENOMEM; 253 goto out_err; 254 } 255 256 from_page = TAILQ_FIRST(&plist); 257 for (i = 0; i < ttm->num_pages; ++i) { 258 to_page = ttm->pages[i]; 259 if (unlikely(to_page == NULL)) { 260 ret = -ENOMEM; 261 goto out_err; 262 } 263 264 uvm_pagecopy(from_page, to_page); 265 from_page = TAILQ_NEXT(from_page, pageq); 266 } 267 268 uvm_obj_unwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT); 269 270 uao_detach(swap_storage); 271 ttm->swap_storage = NULL; 272 ttm->page_flags &= ~TTM_TT_FLAG_SWAPPED; 273 274 return 0; 275 276 out_err: 277 return ret; 278 } 279 280 /** 281 * ttm_tt_swapout - swap out tt object 282 * 283 * @bdev: TTM device structure. 284 * @ttm: The struct ttm_tt. 285 * @gfp_flags: Flags to use for memory allocation. 286 * 287 * Swapout a TT object to a shmem_file, return number of pages swapped out or 288 * negative error code. 289 */ 290 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm, 291 gfp_t gfp_flags) 292 { 293 STUB(); 294 return -ENOSYS; 295 #ifdef notyet 296 loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT; 297 struct uvm_object *swap_storage; 298 struct vm_page *from_page; 299 struct vm_page *to_page; 300 int i, ret; 301 302 swap_storage = uao_create(size, 0); 303 #ifdef notyet 304 if (IS_ERR(swap_storage)) { 305 pr_err("Failed allocating swap storage\n"); 306 return PTR_ERR(swap_storage); 307 } 308 #endif 309 310 for (i = 0; i < ttm->num_pages; ++i) { 311 from_page = ttm->pages[i]; 312 if (unlikely(from_page == NULL)) 313 continue; 314 315 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags); 316 if (IS_ERR(to_page)) { 317 ret = PTR_ERR(to_page); 318 goto out_err; 319 } 320 copy_highpage(to_page, from_page); 321 set_page_dirty(to_page); 322 mark_page_accessed(to_page); 323 put_page(to_page); 324 } 325 326 ttm_tt_unpopulate(bdev, ttm); 327 ttm->swap_storage = swap_storage; 328 ttm->page_flags |= TTM_TT_FLAG_SWAPPED; 329 330 return ttm->num_pages; 331 332 out_err: 333 uao_detach(swap_storage); 334 335 return ret; 336 #endif 337 } 338 339 int ttm_tt_populate(struct ttm_device *bdev, 340 struct ttm_tt *ttm, struct ttm_operation_ctx *ctx) 341 { 342 int ret; 343 344 if (!ttm) 345 return -EINVAL; 346 347 if (ttm_tt_is_populated(ttm)) 348 return 0; 349 350 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) { 351 atomic_long_add(ttm->num_pages, &ttm_pages_allocated); 352 if (bdev->pool.use_dma32) 353 atomic_long_add(ttm->num_pages, 354 &ttm_dma32_pages_allocated); 355 } 356 357 while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit || 358 atomic_long_read(&ttm_dma32_pages_allocated) > 359 ttm_dma32_pages_limit) { 360 361 ret = ttm_global_swapout(ctx, GFP_KERNEL); 362 if (ret == 0) 363 break; 364 if (ret < 0) 365 goto error; 366 } 367 368 if (bdev->funcs->ttm_tt_populate) 369 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx); 370 else 371 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx); 372 if (ret) 373 goto error; 374 375 ttm->page_flags |= TTM_TT_FLAG_PRIV_POPULATED; 376 if (unlikely(ttm->page_flags & TTM_TT_FLAG_SWAPPED)) { 377 ret = ttm_tt_swapin(ttm); 378 if (unlikely(ret != 0)) { 379 ttm_tt_unpopulate(bdev, ttm); 380 return ret; 381 } 382 } 383 384 return 0; 385 386 error: 387 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) { 388 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated); 389 if (bdev->pool.use_dma32) 390 atomic_long_sub(ttm->num_pages, 391 &ttm_dma32_pages_allocated); 392 } 393 return ret; 394 } 395 EXPORT_SYMBOL(ttm_tt_populate); 396 397 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) 398 { 399 if (!ttm_tt_is_populated(ttm)) 400 return; 401 402 if (bdev->funcs->ttm_tt_unpopulate) 403 bdev->funcs->ttm_tt_unpopulate(bdev, ttm); 404 else 405 ttm_pool_free(&bdev->pool, ttm); 406 407 if (!(ttm->page_flags & TTM_TT_FLAG_EXTERNAL)) { 408 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated); 409 if (bdev->pool.use_dma32) 410 atomic_long_sub(ttm->num_pages, 411 &ttm_dma32_pages_allocated); 412 } 413 414 ttm->page_flags &= ~TTM_TT_FLAG_PRIV_POPULATED; 415 } 416 417 #ifdef CONFIG_DEBUG_FS 418 419 /* Test the shrinker functions and dump the result */ 420 static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data) 421 { 422 struct ttm_operation_ctx ctx = { false, false }; 423 424 seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL)); 425 return 0; 426 } 427 DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink); 428 429 #endif 430 431 432 /* 433 * ttm_tt_mgr_init - register with the MM shrinker 434 * 435 * Register with the MM shrinker for swapping out BOs. 436 */ 437 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages) 438 { 439 #ifdef CONFIG_DEBUG_FS 440 debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL, 441 &ttm_tt_debugfs_shrink_fops); 442 #endif 443 444 if (!ttm_pages_limit) 445 ttm_pages_limit = num_pages; 446 447 if (!ttm_dma32_pages_limit) 448 ttm_dma32_pages_limit = num_dma32_pages; 449 } 450 451 static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter, 452 struct iosys_map *dmap, 453 pgoff_t i, bus_space_tag_t bst) 454 { 455 struct ttm_kmap_iter_tt *iter_tt = 456 container_of(iter, typeof(*iter_tt), base); 457 458 #ifdef __linux__ 459 iosys_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i], 460 iter_tt->prot)); 461 #else 462 iosys_map_set_vaddr(dmap, kmap_atomic_prot(iter_tt->tt->pages[i], 463 iter_tt->prot)); 464 #endif 465 } 466 467 static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter, 468 struct iosys_map *map, bus_space_tag_t bst) 469 { 470 #ifdef __linux__ 471 kunmap_local(map->vaddr); 472 #else 473 kunmap_atomic(map->vaddr); 474 #endif 475 } 476 477 static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = { 478 .map_local = ttm_kmap_iter_tt_map_local, 479 .unmap_local = ttm_kmap_iter_tt_unmap_local, 480 .maps_tt = true, 481 }; 482 483 /** 484 * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt 485 * @iter_tt: The struct ttm_kmap_iter_tt to initialize. 486 * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource. 487 * 488 * Return: Pointer to the embedded struct ttm_kmap_iter. 489 */ 490 struct ttm_kmap_iter * 491 ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt, 492 struct ttm_tt *tt) 493 { 494 iter_tt->base.ops = &ttm_kmap_iter_tt_ops; 495 iter_tt->tt = tt; 496 if (tt) 497 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL); 498 else 499 iter_tt->prot = PAGE_KERNEL; 500 501 return &iter_tt->base; 502 } 503 EXPORT_SYMBOL(ttm_kmap_iter_tt_init); 504