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 <drm/drm_cache.h> 38 #include <drm/ttm/ttm_bo_driver.h> 39 40 #include "ttm_module.h" 41 42 static unsigned long ttm_pages_limit; 43 44 MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages"); 45 module_param_named(pages_limit, ttm_pages_limit, ulong, 0644); 46 47 static unsigned long ttm_dma32_pages_limit; 48 49 MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages"); 50 module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644); 51 52 static atomic_long_t ttm_pages_allocated; 53 static atomic_long_t ttm_dma32_pages_allocated; 54 55 /* 56 * Allocates a ttm structure for the given BO. 57 */ 58 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc) 59 { 60 struct ttm_device *bdev = bo->bdev; 61 uint32_t page_flags = 0; 62 63 dma_resv_assert_held(bo->base.resv); 64 65 if (bo->ttm) 66 return 0; 67 68 switch (bo->type) { 69 case ttm_bo_type_device: 70 if (zero_alloc) 71 page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC; 72 break; 73 case ttm_bo_type_kernel: 74 break; 75 case ttm_bo_type_sg: 76 page_flags |= TTM_PAGE_FLAG_SG; 77 break; 78 default: 79 pr_err("Illegal buffer object type\n"); 80 return -EINVAL; 81 } 82 83 bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags); 84 if (unlikely(bo->ttm == NULL)) 85 return -ENOMEM; 86 87 return 0; 88 } 89 90 /* 91 * Allocates storage for pointers to the pages that back the ttm. 92 */ 93 static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm) 94 { 95 ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*), 96 GFP_KERNEL | __GFP_ZERO); 97 if (!ttm->pages) 98 return -ENOMEM; 99 ttm->orders = kvmalloc_array(ttm->num_pages, 100 sizeof(unsigned long), 101 GFP_KERNEL | __GFP_ZERO); 102 if (!ttm->orders) 103 return -ENOMEM; 104 return 0; 105 } 106 107 static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm) 108 { 109 ttm->pages = kvmalloc_array(ttm->num_pages, 110 sizeof(*ttm->pages) + 111 sizeof(*ttm->dma_address), 112 GFP_KERNEL | __GFP_ZERO); 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 = kvmalloc_array(ttm->num_pages, 129 sizeof(*ttm->dma_address), 130 GFP_KERNEL | __GFP_ZERO); 131 if (!ttm->dma_address) 132 return -ENOMEM; 133 return 0; 134 } 135 136 void ttm_tt_destroy_common(struct ttm_device *bdev, struct ttm_tt *ttm) 137 { 138 ttm_tt_unpopulate(bdev, ttm); 139 140 if (ttm->swap_storage) 141 uao_detach(ttm->swap_storage); 142 143 ttm->swap_storage = NULL; 144 } 145 EXPORT_SYMBOL(ttm_tt_destroy_common); 146 147 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm) 148 { 149 bdev->funcs->ttm_tt_destroy(bdev, ttm); 150 } 151 152 static void ttm_tt_init_fields(struct ttm_tt *ttm, 153 struct ttm_buffer_object *bo, 154 uint32_t page_flags, 155 enum ttm_caching caching) 156 { 157 ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT; 158 ttm->caching = ttm_cached; 159 ttm->page_flags = page_flags; 160 ttm->dma_address = NULL; 161 ttm->swap_storage = NULL; 162 ttm->sg = bo->sg; 163 ttm->caching = caching; 164 } 165 166 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo, 167 uint32_t page_flags, enum ttm_caching caching) 168 { 169 ttm_tt_init_fields(ttm, bo, page_flags, caching); 170 171 if (ttm_tt_alloc_page_directory(ttm)) { 172 pr_err("Failed allocating page table\n"); 173 return -ENOMEM; 174 } 175 return 0; 176 } 177 EXPORT_SYMBOL(ttm_tt_init); 178 179 void ttm_tt_fini(struct ttm_tt *ttm) 180 { 181 if (ttm->pages) 182 kvfree(ttm->pages); 183 else 184 kvfree(ttm->dma_address); 185 kvfree(ttm->orders); 186 ttm->pages = NULL; 187 ttm->dma_address = NULL; 188 ttm->orders = NULL; 189 190 bus_dmamap_destroy(ttm->dmat, ttm->map); 191 km_free(ttm->segs, round_page(ttm->num_pages * 192 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero); 193 } 194 EXPORT_SYMBOL(ttm_tt_fini); 195 196 int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo, 197 uint32_t page_flags, enum ttm_caching caching) 198 { 199 int ret; 200 int flags = BUS_DMA_WAITOK; 201 202 ttm_tt_init_fields(ttm, bo, page_flags, caching); 203 204 if (page_flags & TTM_PAGE_FLAG_SG) 205 ret = ttm_sg_tt_alloc_page_directory(ttm); 206 else 207 ret = ttm_dma_tt_alloc_page_directory(ttm); 208 if (ret) { 209 pr_err("Failed allocating page table\n"); 210 return -ENOMEM; 211 } 212 213 ttm->segs = km_alloc(round_page(ttm->num_pages * 214 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero, &kd_waitok); 215 216 ttm->dmat = bo->bdev->dmat; 217 218 if (bo->bdev->pool.use_dma32 == false) 219 flags |= BUS_DMA_64BIT; 220 if (bus_dmamap_create(ttm->dmat, ttm->num_pages << PAGE_SHIFT, 221 ttm->num_pages, ttm->num_pages << PAGE_SHIFT, 0, flags, 222 &ttm->map)) { 223 km_free(ttm->segs, round_page(ttm->num_pages * 224 sizeof(bus_dma_segment_t)), &kv_any, &kp_zero); 225 if (ttm->pages) { 226 kvfree(ttm->pages); 227 kvfree(ttm->orders); 228 } else 229 kvfree(ttm->dma_address); 230 ttm->pages = NULL; 231 ttm->orders = NULL; 232 ttm->dma_address = NULL; 233 pr_err("Failed allocating page table\n"); 234 return -ENOMEM; 235 } 236 237 return 0; 238 } 239 EXPORT_SYMBOL(ttm_sg_tt_init); 240 241 int ttm_tt_swapin(struct ttm_tt *ttm) 242 { 243 struct uvm_object *swap_storage; 244 struct vm_page *from_page; 245 struct vm_page *to_page; 246 struct pglist plist; 247 int i, ret; 248 249 swap_storage = ttm->swap_storage; 250 BUG_ON(swap_storage == NULL); 251 252 TAILQ_INIT(&plist); 253 if (uvm_obj_wire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT, 254 &plist)) { 255 ret = -ENOMEM; 256 goto out_err; 257 } 258 259 from_page = TAILQ_FIRST(&plist); 260 for (i = 0; i < ttm->num_pages; ++i) { 261 to_page = ttm->pages[i]; 262 if (unlikely(to_page == NULL)) { 263 ret = -ENOMEM; 264 goto out_err; 265 } 266 267 uvm_pagecopy(from_page, to_page); 268 from_page = TAILQ_NEXT(from_page, pageq); 269 } 270 271 uvm_obj_unwire(swap_storage, 0, ttm->num_pages << PAGE_SHIFT); 272 273 uao_detach(swap_storage); 274 ttm->swap_storage = NULL; 275 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; 276 277 return 0; 278 279 out_err: 280 return ret; 281 } 282 283 /** 284 * ttm_tt_swapout - swap out tt object 285 * 286 * @bdev: TTM device structure. 287 * @ttm: The struct ttm_tt. 288 * @gfp_flags: Flags to use for memory allocation. 289 * 290 * Swapout a TT object to a shmem_file, return number of pages swapped out or 291 * negative error code. 292 */ 293 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm, 294 gfp_t gfp_flags) 295 { 296 STUB(); 297 return -ENOSYS; 298 #ifdef notyet 299 loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT; 300 struct uvm_object *swap_storage; 301 struct vm_page *from_page; 302 struct vm_page *to_page; 303 int i, ret; 304 305 swap_storage = uao_create(size, 0); 306 #ifdef notyet 307 if (IS_ERR(swap_storage)) { 308 pr_err("Failed allocating swap storage\n"); 309 return PTR_ERR(swap_storage); 310 } 311 #endif 312 313 for (i = 0; i < ttm->num_pages; ++i) { 314 from_page = ttm->pages[i]; 315 if (unlikely(from_page == NULL)) 316 continue; 317 318 to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags); 319 if (IS_ERR(to_page)) { 320 ret = PTR_ERR(to_page); 321 goto out_err; 322 } 323 copy_highpage(to_page, from_page); 324 set_page_dirty(to_page); 325 mark_page_accessed(to_page); 326 put_page(to_page); 327 } 328 329 ttm_tt_unpopulate(bdev, ttm); 330 ttm->swap_storage = swap_storage; 331 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; 332 333 return ttm->num_pages; 334 335 out_err: 336 uao_detach(swap_storage); 337 338 return ret; 339 #endif 340 } 341 342 static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm) 343 { 344 #ifdef __linux__ 345 pgoff_t i; 346 347 if (ttm->page_flags & TTM_PAGE_FLAG_SG) 348 return; 349 350 for (i = 0; i < ttm->num_pages; ++i) 351 ttm->pages[i]->mapping = bdev->dev_mapping; 352 #endif 353 } 354 355 int ttm_tt_populate(struct ttm_device *bdev, 356 struct ttm_tt *ttm, struct ttm_operation_ctx *ctx) 357 { 358 int ret; 359 360 if (!ttm) 361 return -EINVAL; 362 363 if (ttm_tt_is_populated(ttm)) 364 return 0; 365 366 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) { 367 atomic_long_add(ttm->num_pages, &ttm_pages_allocated); 368 if (bdev->pool.use_dma32) 369 atomic_long_add(ttm->num_pages, 370 &ttm_dma32_pages_allocated); 371 } 372 373 while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit || 374 atomic_long_read(&ttm_dma32_pages_allocated) > 375 ttm_dma32_pages_limit) { 376 377 ret = ttm_global_swapout(ctx, GFP_KERNEL); 378 if (ret == 0) 379 break; 380 if (ret < 0) 381 goto error; 382 } 383 384 if (bdev->funcs->ttm_tt_populate) 385 ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx); 386 else 387 ret = ttm_pool_alloc(&bdev->pool, ttm, ctx); 388 if (ret) 389 goto error; 390 391 ttm_tt_add_mapping(bdev, ttm); 392 ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED; 393 if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) { 394 ret = ttm_tt_swapin(ttm); 395 if (unlikely(ret != 0)) { 396 ttm_tt_unpopulate(bdev, ttm); 397 return ret; 398 } 399 } 400 401 return 0; 402 403 error: 404 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) { 405 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated); 406 if (bdev->pool.use_dma32) 407 atomic_long_sub(ttm->num_pages, 408 &ttm_dma32_pages_allocated); 409 } 410 return ret; 411 } 412 EXPORT_SYMBOL(ttm_tt_populate); 413 414 static void ttm_tt_clear_mapping(struct ttm_tt *ttm) 415 { 416 int i; 417 struct vm_page *page; 418 419 if (ttm->page_flags & TTM_PAGE_FLAG_SG) 420 return; 421 422 for (i = 0; i < ttm->num_pages; ++i) { 423 page = ttm->pages[i]; 424 if (unlikely(page == NULL)) 425 continue; 426 pmap_page_protect(page, PROT_NONE); 427 } 428 } 429 430 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm) 431 { 432 if (!ttm_tt_is_populated(ttm)) 433 return; 434 435 ttm_tt_clear_mapping(ttm); 436 if (bdev->funcs->ttm_tt_unpopulate) 437 bdev->funcs->ttm_tt_unpopulate(bdev, ttm); 438 else 439 ttm_pool_free(&bdev->pool, ttm); 440 441 if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) { 442 atomic_long_sub(ttm->num_pages, &ttm_pages_allocated); 443 if (bdev->pool.use_dma32) 444 atomic_long_sub(ttm->num_pages, 445 &ttm_dma32_pages_allocated); 446 } 447 448 ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED; 449 } 450 451 #ifdef CONFIG_DEBUG_FS 452 453 /* Test the shrinker functions and dump the result */ 454 static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data) 455 { 456 struct ttm_operation_ctx ctx = { false, false }; 457 458 seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL)); 459 return 0; 460 } 461 DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink); 462 463 #endif 464 465 466 /* 467 * ttm_tt_mgr_init - register with the MM shrinker 468 * 469 * Register with the MM shrinker for swapping out BOs. 470 */ 471 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages) 472 { 473 #ifdef CONFIG_DEBUG_FS 474 debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL, 475 &ttm_tt_debugfs_shrink_fops); 476 #endif 477 478 if (!ttm_pages_limit) 479 ttm_pages_limit = num_pages; 480 481 if (!ttm_dma32_pages_limit) 482 ttm_dma32_pages_limit = num_dma32_pages; 483 } 484 485 static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter, 486 struct dma_buf_map *dmap, 487 pgoff_t i, bus_space_tag_t bst) 488 { 489 struct ttm_kmap_iter_tt *iter_tt = 490 container_of(iter, typeof(*iter_tt), base); 491 492 #ifdef __linux__ 493 dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i], 494 iter_tt->prot)); 495 #else 496 dma_buf_map_set_vaddr(dmap, kmap_atomic_prot(iter_tt->tt->pages[i], 497 iter_tt->prot)); 498 #endif 499 } 500 501 static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter, 502 struct dma_buf_map *map, bus_space_tag_t bst) 503 { 504 #ifdef __linux__ 505 kunmap_local(map->vaddr); 506 #else 507 kunmap_atomic(map->vaddr); 508 #endif 509 } 510 511 static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = { 512 .map_local = ttm_kmap_iter_tt_map_local, 513 .unmap_local = ttm_kmap_iter_tt_unmap_local, 514 .maps_tt = true, 515 }; 516 517 /** 518 * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt 519 * @iter_tt: The struct ttm_kmap_iter_tt to initialize. 520 * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource. 521 * 522 * Return: Pointer to the embedded struct ttm_kmap_iter. 523 */ 524 struct ttm_kmap_iter * 525 ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt, 526 struct ttm_tt *tt) 527 { 528 iter_tt->base.ops = &ttm_kmap_iter_tt_ops; 529 iter_tt->tt = tt; 530 if (tt) 531 iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL); 532 else 533 iter_tt->prot = PAGE_KERNEL; 534 535 return &iter_tt->base; 536 } 537 EXPORT_SYMBOL(ttm_kmap_iter_tt_init); 538