drivers/gpu/drm/ttm/ttm_tt.c

   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_cache.h"
  42 #include "drm_mem_util.h"
  43 #include "ttm/ttm_module.h"
  44 #include "ttm/ttm_bo_driver.h"
  45 #include "ttm/ttm_placement.h"
  46 #include "ttm/ttm_page_alloc.h"
  47
  48 /**
  49  * Allocates storage for pointers to the pages that back the ttm.
  50  */
  51 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
  52 {
  53         ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
  54 }
  55
  56 static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
  57 {
  58         ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages, sizeof(void*));
  59         ttm->dma_address = drm_calloc_large(ttm->ttm.num_pages,
  60                                             sizeof(*ttm->dma_address));
  61 }
  62
  63 #ifdef CONFIG_X86
  64 static inline int ttm_tt_set_page_caching(struct page *p,
  65                                           enum ttm_caching_state c_old,
  66                                           enum ttm_caching_state c_new)
  67 {
  68         int ret = 0;
  69
  70         if (PageHighMem(p))
  71                 return 0;
  72
  73         if (c_old != tt_cached) {
  74                 /* p isn't in the default caching state, set it to
  75                  * writeback first to free its current memtype. */
  76
  77                 ret = set_pages_wb(p, 1);
  78                 if (ret)
  79                         return ret;
  80         }
  81
  82         if (c_new == tt_wc)
  83                 ret = set_memory_wc((unsigned long) page_address(p), 1);
  84         else if (c_new == tt_uncached)
  85                 ret = set_pages_uc(p, 1);
  86
  87         return ret;
  88 }
  89 #else /* CONFIG_X86 */
  90 static inline int ttm_tt_set_page_caching(struct page *p,
  91                                           enum ttm_caching_state c_old,
  92                                           enum ttm_caching_state c_new)
  93 {
  94         return 0;
  95 }
  96 #endif /* CONFIG_X86 */
  97
  98 /*
  99  * Change caching policy for the linear kernel map
 100  * for range of pages in a ttm.
 101  */
 102
 103 static int ttm_tt_set_caching(struct ttm_tt *ttm,
 104                               enum ttm_caching_state c_state)
 105 {
 106         int i, j;
 107         struct page *cur_page;
 108         int ret;
 109
 110         if (ttm->caching_state == c_state)
 111                 return 0;
 112
 113         if (ttm->state == tt_unpopulated) {
 114                 /* Change caching but don't populate */
 115                 ttm->caching_state = c_state;
 116                 return 0;
 117         }
 118
 119         if (ttm->caching_state == tt_cached)
 120                 drm_clflush_pages(ttm->pages, ttm->num_pages);
 121
 122         for (i = 0; i < ttm->num_pages; ++i) {
 123                 cur_page = ttm->pages[i];
 124                 if (likely(cur_page != NULL)) {
 125                         ret = ttm_tt_set_page_caching(cur_page,
 126                                                       ttm->caching_state,
 127                                                       c_state);
 128                         if (unlikely(ret != 0))
 129                                 goto out_err;
 130                 }
 131         }
 132
 133         ttm->caching_state = c_state;
 134
 135         return 0;
 136
 137 out_err:
 138         for (j = 0; j < i; ++j) {
 139                 cur_page = ttm->pages[j];
 140                 if (likely(cur_page != NULL)) {
 141                         (void)ttm_tt_set_page_caching(cur_page, c_state,
 142                                                       ttm->caching_state);
 143                 }
 144         }
 145
 146         return ret;
 147 }
 148
 149 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
 150 {
 151         enum ttm_caching_state state;
 152
 153         if (placement & TTM_PL_FLAG_WC)
 154                 state = tt_wc;
 155         else if (placement & TTM_PL_FLAG_UNCACHED)
 156                 state = tt_uncached;
 157         else
 158                 state = tt_cached;
 159
 160         return ttm_tt_set_caching(ttm, state);
 161 }
 162 EXPORT_SYMBOL(ttm_tt_set_placement_caching);
 163
 164 void ttm_tt_destroy(struct ttm_tt *ttm)
 165 {
 166         if (unlikely(ttm == NULL))
 167                 return;
 168
 169         if (ttm->state == tt_bound) {
 170                 ttm_tt_unbind(ttm);
 171         }
 172
 173         if (likely(ttm->pages != NULL)) {
 174                 ttm->bdev->driver->ttm_tt_unpopulate(ttm);
 175         }
 176
 177         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
 178             ttm->swap_storage)
 179                 fput(ttm->swap_storage);
 180
 181         ttm->swap_storage = NULL;
 182         ttm->func->destroy(ttm);
 183 }
 184
 185 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
 186                 unsigned long size, uint32_t page_flags,
 187                 struct page *dummy_read_page)
 188 {
 189         ttm->bdev = bdev;
 190         ttm->glob = bdev->glob;
 191         ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 192         ttm->caching_state = tt_cached;
 193         ttm->page_flags = page_flags;
 194         ttm->dummy_read_page = dummy_read_page;
 195         ttm->state = tt_unpopulated;
 196         ttm->swap_storage = NULL;
 197
 198         ttm_tt_alloc_page_directory(ttm);
 199         if (!ttm->pages) {
 200                 ttm_tt_destroy(ttm);
 201                 pr_err("Failed allocating page table\n");
 202                 return -ENOMEM;
 203         }
 204         return 0;
 205 }
 206 EXPORT_SYMBOL(ttm_tt_init);
 207
 208 void ttm_tt_fini(struct ttm_tt *ttm)
 209 {
 210         drm_free_large(ttm->pages);
 211         ttm->pages = NULL;
 212 }
 213 EXPORT_SYMBOL(ttm_tt_fini);
 214
 215 int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
 216                 unsigned long size, uint32_t page_flags,
 217                 struct page *dummy_read_page)
 218 {
 219         struct ttm_tt *ttm = &ttm_dma->ttm;
 220
 221         ttm->bdev = bdev;
 222         ttm->glob = bdev->glob;
 223         ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 224         ttm->caching_state = tt_cached;
 225         ttm->page_flags = page_flags;
 226         ttm->dummy_read_page = dummy_read_page;
 227         ttm->state = tt_unpopulated;
 228         ttm->swap_storage = NULL;
 229
 230         INIT_LIST_HEAD(&ttm_dma->pages_list);
 231         ttm_dma_tt_alloc_page_directory(ttm_dma);
 232         if (!ttm->pages || !ttm_dma->dma_address) {
 233                 ttm_tt_destroy(ttm);
 234                 pr_err("Failed allocating page table\n");
 235                 return -ENOMEM;
 236         }
 237         return 0;
 238 }
 239 EXPORT_SYMBOL(ttm_dma_tt_init);
 240
 241 void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
 242 {
 243         struct ttm_tt *ttm = &ttm_dma->ttm;
 244
 245         drm_free_large(ttm->pages);
 246         ttm->pages = NULL;
 247         drm_free_large(ttm_dma->dma_address);
 248         ttm_dma->dma_address = NULL;
 249 }
 250 EXPORT_SYMBOL(ttm_dma_tt_fini);
 251
 252 void ttm_tt_unbind(struct ttm_tt *ttm)
 253 {
 254         int ret;
 255
 256         if (ttm->state == tt_bound) {
 257                 ret = ttm->func->unbind(ttm);
 258                 BUG_ON(ret);
 259                 ttm->state = tt_unbound;
 260         }
 261 }
 262
 263 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 264 {
 265         int ret = 0;
 266
 267         if (!ttm)
 268                 return -EINVAL;
 269
 270         if (ttm->state == tt_bound)
 271                 return 0;
 272
 273         ret = ttm->bdev->driver->ttm_tt_populate(ttm);
 274         if (ret)
 275                 return ret;
 276
 277         ret = ttm->func->bind(ttm, bo_mem);
 278         if (unlikely(ret != 0))
 279                 return ret;
 280
 281         ttm->state = tt_bound;
 282
 283         return 0;
 284 }
 285 EXPORT_SYMBOL(ttm_tt_bind);
 286
 287 int ttm_tt_swapin(struct ttm_tt *ttm)
 288 {
 289         struct address_space *swap_space;
 290         struct file *swap_storage;
 291         struct page *from_page;
 292         struct page *to_page;
 293         void *from_virtual;
 294         void *to_virtual;
 295         int i;
 296         int ret = -ENOMEM;
 297
 298         swap_storage = ttm->swap_storage;
 299         BUG_ON(swap_storage == NULL);
 300
 301         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 302
 303         for (i = 0; i < ttm->num_pages; ++i) {
 304                 from_page = shmem_read_mapping_page(swap_space, i);
 305                 if (IS_ERR(from_page)) {
 306                         ret = PTR_ERR(from_page);
 307                         goto out_err;
 308                 }
 309                 to_page = ttm->pages[i];
 310                 if (unlikely(to_page == NULL))
 311                         goto out_err;
 312
 313                 preempt_disable();
 314                 from_virtual = kmap_atomic(from_page);
 315                 to_virtual = kmap_atomic(to_page);
 316                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 317                 kunmap_atomic(to_virtual);
 318                 kunmap_atomic(from_virtual);
 319                 preempt_enable();
 320                 page_cache_release(from_page);
 321         }
 322
 323         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
 324                 fput(swap_storage);
 325         ttm->swap_storage = NULL;
 326         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 327
 328         return 0;
 329 out_err:
 330         return ret;
 331 }
 332
 333 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 334 {
 335         struct address_space *swap_space;
 336         struct file *swap_storage;
 337         struct page *from_page;
 338         struct page *to_page;
 339         void *from_virtual;
 340         void *to_virtual;
 341         int i;
 342         int ret = -ENOMEM;
 343
 344         BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
 345         BUG_ON(ttm->caching_state != tt_cached);
 346
 347         if (!persistent_swap_storage) {
 348                 swap_storage = shmem_file_setup("ttm swap",
 349                                                 ttm->num_pages << PAGE_SHIFT,
 350                                                 0);
 351                 if (unlikely(IS_ERR(swap_storage))) {
 352                         pr_err("Failed allocating swap storage\n");
 353                         return PTR_ERR(swap_storage);
 354                 }
 355         } else
 356                 swap_storage = persistent_swap_storage;
 357
 358         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 359
 360         for (i = 0; i < ttm->num_pages; ++i) {
 361                 from_page = ttm->pages[i];
 362                 if (unlikely(from_page == NULL))
 363                         continue;
 364                 to_page = shmem_read_mapping_page(swap_space, i);
 365                 if (unlikely(IS_ERR(to_page))) {
 366                         ret = PTR_ERR(to_page);
 367                         goto out_err;
 368                 }
 369                 preempt_disable();
 370                 from_virtual = kmap_atomic(from_page);
 371                 to_virtual = kmap_atomic(to_page);
 372                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 373                 kunmap_atomic(to_virtual);
 374                 kunmap_atomic(from_virtual);
 375                 preempt_enable();
 376                 set_page_dirty(to_page);
 377                 mark_page_accessed(to_page);
 378                 page_cache_release(to_page);
 379         }
 380
 381         ttm->bdev->driver->ttm_tt_unpopulate(ttm);
 382         ttm->swap_storage = swap_storage;
 383         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 384         if (persistent_swap_storage)
 385                 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
 386
 387         return 0;
 388 out_err:
 389         if (!persistent_swap_storage)
 390                 fput(swap_storage);
 391
 392         return ret;
 393 }