1 /************************************************************************** 2 * 3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL 21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, 22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 24 * USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 /* 28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com> 29 */ 30 31 #define pr_fmt(fmt) "[TTM] " fmt 32 33 #include <linux/sched.h> 34 #include <linux/highmem.h> 35 #include <linux/pagemap.h> 36 #include <linux/shmem_fs.h> 37 #include <linux/file.h> 38 #include <linux/swap.h> 39 #include <linux/slab.h> 40 #include <linux/export.h> 41 #include <drm/drm_cache.h> 42 #include <drm/ttm/ttm_module.h> 43 #include <drm/ttm/ttm_bo_driver.h> 44 #include <drm/ttm/ttm_placement.h> 45 #include <drm/ttm/ttm_page_alloc.h> 46 #ifdef CONFIG_X86 47 #include <asm/set_memory.h> 48 #endif 49 50 /** 51 * Allocates storage for pointers to the pages that back the ttm. 52 */ 53 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm) 54 { 55 ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*), 56 GFP_KERNEL | __GFP_ZERO); 57 } 58 59 static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm) 60 { 61 ttm->ttm.pages = kvmalloc_array(ttm->ttm.num_pages, 62 sizeof(*ttm->ttm.pages) + 63 sizeof(*ttm->dma_address), 64 GFP_KERNEL | __GFP_ZERO); 65 ttm->dma_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages); 66 } 67 68 #ifdef CONFIG_X86 69 static inline int ttm_tt_set_page_caching(struct page *p, 70 enum ttm_caching_state c_old, 71 enum ttm_caching_state c_new) 72 { 73 int ret = 0; 74 75 if (PageHighMem(p)) 76 return 0; 77 78 if (c_old != tt_cached) { 79 /* p isn't in the default caching state, set it to 80 * writeback first to free its current memtype. */ 81 82 ret = set_pages_wb(p, 1); 83 if (ret) 84 return ret; 85 } 86 87 if (c_new == tt_wc) 88 ret = set_memory_wc((unsigned long) page_address(p), 1); 89 else if (c_new == tt_uncached) 90 ret = set_pages_uc(p, 1); 91 92 return ret; 93 } 94 #else /* CONFIG_X86 */ 95 static inline int ttm_tt_set_page_caching(struct page *p, 96 enum ttm_caching_state c_old, 97 enum ttm_caching_state c_new) 98 { 99 return 0; 100 } 101 #endif /* CONFIG_X86 */ 102 103 /* 104 * Change caching policy for the linear kernel map 105 * for range of pages in a ttm. 106 */ 107 108 static int ttm_tt_set_caching(struct ttm_tt *ttm, 109 enum ttm_caching_state c_state) 110 { 111 int i, j; 112 struct page *cur_page; 113 int ret; 114 115 if (ttm->caching_state == c_state) 116 return 0; 117 118 if (ttm->state == tt_unpopulated) { 119 /* Change caching but don't populate */ 120 ttm->caching_state = c_state; 121 return 0; 122 } 123 124 if (ttm->caching_state == tt_cached) 125 drm_clflush_pages(ttm->pages, ttm->num_pages); 126 127 for (i = 0; i < ttm->num_pages; ++i) { 128 cur_page = ttm->pages[i]; 129 if (likely(cur_page != NULL)) { 130 ret = ttm_tt_set_page_caching(cur_page, 131 ttm->caching_state, 132 c_state); 133 if (unlikely(ret != 0)) 134 goto out_err; 135 } 136 } 137 138 ttm->caching_state = c_state; 139 140 return 0; 141 142 out_err: 143 for (j = 0; j < i; ++j) { 144 cur_page = ttm->pages[j]; 145 if (likely(cur_page != NULL)) { 146 (void)ttm_tt_set_page_caching(cur_page, c_state, 147 ttm->caching_state); 148 } 149 } 150 151 return ret; 152 } 153 154 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement) 155 { 156 enum ttm_caching_state state; 157 158 if (placement & TTM_PL_FLAG_WC) 159 state = tt_wc; 160 else if (placement & TTM_PL_FLAG_UNCACHED) 161 state = tt_uncached; 162 else 163 state = tt_cached; 164 165 return ttm_tt_set_caching(ttm, state); 166 } 167 EXPORT_SYMBOL(ttm_tt_set_placement_caching); 168 169 void ttm_tt_destroy(struct ttm_tt *ttm) 170 { 171 if (ttm == NULL) 172 return; 173 174 ttm_tt_unbind(ttm); 175 176 if (ttm->state == tt_unbound) 177 ttm_tt_unpopulate(ttm); 178 179 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) && 180 ttm->swap_storage) 181 fput(ttm->swap_storage); 182 183 ttm->swap_storage = NULL; 184 ttm->func->destroy(ttm); 185 } 186 187 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, 188 unsigned long size, uint32_t page_flags, 189 struct page *dummy_read_page) 190 { 191 ttm->bdev = bdev; 192 ttm->glob = bdev->glob; 193 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 194 ttm->caching_state = tt_cached; 195 ttm->page_flags = page_flags; 196 ttm->dummy_read_page = dummy_read_page; 197 ttm->state = tt_unpopulated; 198 ttm->swap_storage = NULL; 199 200 ttm_tt_alloc_page_directory(ttm); 201 if (!ttm->pages) { 202 ttm_tt_destroy(ttm); 203 pr_err("Failed allocating page table\n"); 204 return -ENOMEM; 205 } 206 return 0; 207 } 208 EXPORT_SYMBOL(ttm_tt_init); 209 210 void ttm_tt_fini(struct ttm_tt *ttm) 211 { 212 kvfree(ttm->pages); 213 ttm->pages = NULL; 214 } 215 EXPORT_SYMBOL(ttm_tt_fini); 216 217 int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev, 218 unsigned long size, uint32_t page_flags, 219 struct page *dummy_read_page) 220 { 221 struct ttm_tt *ttm = &ttm_dma->ttm; 222 223 ttm->bdev = bdev; 224 ttm->glob = bdev->glob; 225 ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 226 ttm->caching_state = tt_cached; 227 ttm->page_flags = page_flags; 228 ttm->dummy_read_page = dummy_read_page; 229 ttm->state = tt_unpopulated; 230 ttm->swap_storage = NULL; 231 232 INIT_LIST_HEAD(&ttm_dma->pages_list); 233 ttm_dma_tt_alloc_page_directory(ttm_dma); 234 if (!ttm->pages) { 235 ttm_tt_destroy(ttm); 236 pr_err("Failed allocating page table\n"); 237 return -ENOMEM; 238 } 239 return 0; 240 } 241 EXPORT_SYMBOL(ttm_dma_tt_init); 242 243 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma) 244 { 245 struct ttm_tt *ttm = &ttm_dma->ttm; 246 247 kvfree(ttm->pages); 248 ttm->pages = NULL; 249 ttm_dma->dma_address = NULL; 250 } 251 EXPORT_SYMBOL(ttm_dma_tt_fini); 252 253 void ttm_tt_unbind(struct ttm_tt *ttm) 254 { 255 int ret; 256 257 if (ttm->state == tt_bound) { 258 ret = ttm->func->unbind(ttm); 259 BUG_ON(ret); 260 ttm->state = tt_unbound; 261 } 262 } 263 264 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem) 265 { 266 int ret = 0; 267 268 if (!ttm) 269 return -EINVAL; 270 271 if (ttm->state == tt_bound) 272 return 0; 273 274 ret = ttm->bdev->driver->ttm_tt_populate(ttm); 275 if (ret) 276 return ret; 277 278 ret = ttm->func->bind(ttm, bo_mem); 279 if (unlikely(ret != 0)) 280 return ret; 281 282 ttm->state = tt_bound; 283 284 return 0; 285 } 286 EXPORT_SYMBOL(ttm_tt_bind); 287 288 int ttm_tt_swapin(struct ttm_tt *ttm) 289 { 290 struct address_space *swap_space; 291 struct file *swap_storage; 292 struct page *from_page; 293 struct page *to_page; 294 int i; 295 int ret = -ENOMEM; 296 297 swap_storage = ttm->swap_storage; 298 BUG_ON(swap_storage == NULL); 299 300 swap_space = swap_storage->f_mapping; 301 302 for (i = 0; i < ttm->num_pages; ++i) { 303 from_page = shmem_read_mapping_page(swap_space, i); 304 if (IS_ERR(from_page)) { 305 ret = PTR_ERR(from_page); 306 goto out_err; 307 } 308 to_page = ttm->pages[i]; 309 if (unlikely(to_page == NULL)) 310 goto out_err; 311 312 copy_highpage(to_page, from_page); 313 put_page(from_page); 314 } 315 316 if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP)) 317 fput(swap_storage); 318 ttm->swap_storage = NULL; 319 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED; 320 321 return 0; 322 out_err: 323 return ret; 324 } 325 326 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage) 327 { 328 struct address_space *swap_space; 329 struct file *swap_storage; 330 struct page *from_page; 331 struct page *to_page; 332 int i; 333 int ret = -ENOMEM; 334 335 BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated); 336 BUG_ON(ttm->caching_state != tt_cached); 337 338 if (!persistent_swap_storage) { 339 swap_storage = shmem_file_setup("ttm swap", 340 ttm->num_pages << PAGE_SHIFT, 341 0); 342 if (IS_ERR(swap_storage)) { 343 pr_err("Failed allocating swap storage\n"); 344 return PTR_ERR(swap_storage); 345 } 346 } else 347 swap_storage = persistent_swap_storage; 348 349 swap_space = swap_storage->f_mapping; 350 351 for (i = 0; i < ttm->num_pages; ++i) { 352 from_page = ttm->pages[i]; 353 if (unlikely(from_page == NULL)) 354 continue; 355 to_page = shmem_read_mapping_page(swap_space, i); 356 if (IS_ERR(to_page)) { 357 ret = PTR_ERR(to_page); 358 goto out_err; 359 } 360 copy_highpage(to_page, from_page); 361 set_page_dirty(to_page); 362 mark_page_accessed(to_page); 363 put_page(to_page); 364 } 365 366 ttm_tt_unpopulate(ttm); 367 ttm->swap_storage = swap_storage; 368 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED; 369 if (persistent_swap_storage) 370 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP; 371 372 return 0; 373 out_err: 374 if (!persistent_swap_storage) 375 fput(swap_storage); 376 377 return ret; 378 } 379 380 static void ttm_tt_clear_mapping(struct ttm_tt *ttm) 381 { 382 pgoff_t i; 383 struct page **page = ttm->pages; 384 385 if (ttm->page_flags & TTM_PAGE_FLAG_SG) 386 return; 387 388 for (i = 0; i < ttm->num_pages; ++i) { 389 (*page)->mapping = NULL; 390 (*page++)->index = 0; 391 } 392 } 393 394 void ttm_tt_unpopulate(struct ttm_tt *ttm) 395 { 396 if (ttm->state == tt_unpopulated) 397 return; 398 399 ttm_tt_clear_mapping(ttm); 400 ttm->bdev->driver->ttm_tt_unpopulate(ttm); 401 } 402