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 #include <linux/sched.h>
  32 #include <linux/highmem.h>
  33 #include <linux/pagemap.h>
  34 #include <linux/shmem_fs.h>
  35 #include <linux/file.h>
  36 #include <linux/swap.h>
  37 #include <linux/slab.h>
  38 #include <linux/export.h>
  39 #include "drm_cache.h"
  40 #include "drm_mem_util.h"
  41 #include "ttm/ttm_module.h"
  42 #include "ttm/ttm_bo_driver.h"
  43 #include "ttm/ttm_placement.h"
  44 #include "ttm/ttm_page_alloc.h"
  45
  46 /**
  47  * Allocates storage for pointers to the pages that back the ttm.
  48  */
  49 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
  50 {
  51         ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(*ttm->pages));
  52         ttm->dma_address = drm_calloc_large(ttm->num_pages,
  53                                             sizeof(*ttm->dma_address));
  54 }
  55
  56 static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
  57 {
  58         drm_free_large(ttm->pages);
  59         ttm->pages = NULL;
  60         drm_free_large(ttm->dma_address);
  61         ttm->dma_address = NULL;
  62 }
  63
  64 #ifdef CONFIG_X86
  65 static inline int ttm_tt_set_page_caching(struct page *p,
  66                                           enum ttm_caching_state c_old,
  67                                           enum ttm_caching_state c_new)
  68 {
  69         int ret = 0;
  70
  71         if (PageHighMem(p))
  72                 return 0;
  73
  74         if (c_old != tt_cached) {
  75                 /* p isn't in the default caching state, set it to
  76                  * writeback first to free its current memtype. */
  77
  78                 ret = set_pages_wb(p, 1);
  79                 if (ret)
  80                         return ret;
  81         }
  82
  83         if (c_new == tt_wc)
  84                 ret = set_memory_wc((unsigned long) page_address(p), 1);
  85         else if (c_new == tt_uncached)
  86                 ret = set_pages_uc(p, 1);
  87
  88         return ret;
  89 }
  90 #else /* CONFIG_X86 */
  91 static inline int ttm_tt_set_page_caching(struct page *p,
  92                                           enum ttm_caching_state c_old,
  93                                           enum ttm_caching_state c_new)
  94 {
  95         return 0;
  96 }
  97 #endif /* CONFIG_X86 */
  98
  99 /*
 100  * Change caching policy for the linear kernel map
 101  * for range of pages in a ttm.
 102  */
 103
 104 static int ttm_tt_set_caching(struct ttm_tt *ttm,
 105                               enum ttm_caching_state c_state)
 106 {
 107         int i, j;
 108         struct page *cur_page;
 109         int ret;
 110
 111         if (ttm->caching_state == c_state)
 112                 return 0;
 113
 114         if (ttm->state == tt_unpopulated) {
 115                 /* Change caching but don't populate */
 116                 ttm->caching_state = c_state;
 117                 return 0;
 118         }
 119
 120         if (ttm->caching_state == tt_cached)
 121                 drm_clflush_pages(ttm->pages, ttm->num_pages);
 122
 123         for (i = 0; i < ttm->num_pages; ++i) {
 124                 cur_page = ttm->pages[i];
 125                 if (likely(cur_page != NULL)) {
 126                         ret = ttm_tt_set_page_caching(cur_page,
 127                                                       ttm->caching_state,
 128                                                       c_state);
 129                         if (unlikely(ret != 0))
 130                                 goto out_err;
 131                 }
 132         }
 133
 134         ttm->caching_state = c_state;
 135
 136         return 0;
 137
 138 out_err:
 139         for (j = 0; j < i; ++j) {
 140                 cur_page = ttm->pages[j];
 141                 if (likely(cur_page != NULL)) {
 142                         (void)ttm_tt_set_page_caching(cur_page, c_state,
 143                                                       ttm->caching_state);
 144                 }
 145         }
 146
 147         return ret;
 148 }
 149
 150 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
 151 {
 152         enum ttm_caching_state state;
 153
 154         if (placement & TTM_PL_FLAG_WC)
 155                 state = tt_wc;
 156         else if (placement & TTM_PL_FLAG_UNCACHED)
 157                 state = tt_uncached;
 158         else
 159                 state = tt_cached;
 160
 161         return ttm_tt_set_caching(ttm, state);
 162 }
 163 EXPORT_SYMBOL(ttm_tt_set_placement_caching);
 164
 165 void ttm_tt_destroy(struct ttm_tt *ttm)
 166 {
 167         if (unlikely(ttm == NULL))
 168                 return;
 169
 170         if (ttm->state == tt_bound) {
 171                 ttm_tt_unbind(ttm);
 172         }
 173
 174         if (likely(ttm->pages != NULL)) {
 175                 ttm->bdev->driver->ttm_tt_unpopulate(ttm);
 176                 ttm_tt_free_page_directory(ttm);
 177         }
 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
 199         ttm_tt_alloc_page_directory(ttm);
 200         if (!ttm->pages || !ttm->dma_address) {
 201                 ttm_tt_destroy(ttm);
 202                 printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
 203                 return -ENOMEM;
 204         }
 205         return 0;
 206 }
 207 EXPORT_SYMBOL(ttm_tt_init);
 208
 209 void ttm_tt_unbind(struct ttm_tt *ttm)
 210 {
 211         int ret;
 212
 213         if (ttm->state == tt_bound) {
 214                 ret = ttm->func->unbind(ttm);
 215                 BUG_ON(ret);
 216                 ttm->state = tt_unbound;
 217         }
 218 }
 219
 220 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 221 {
 222         int ret = 0;
 223
 224         if (!ttm)
 225                 return -EINVAL;
 226
 227         if (ttm->state == tt_bound)
 228                 return 0;
 229
 230         ret = ttm->bdev->driver->ttm_tt_populate(ttm);
 231         if (ret)
 232                 return ret;
 233
 234         ret = ttm->func->bind(ttm, bo_mem);
 235         if (unlikely(ret != 0))
 236                 return ret;
 237
 238         ttm->state = tt_bound;
 239
 240         return 0;
 241 }
 242 EXPORT_SYMBOL(ttm_tt_bind);
 243
 244 int ttm_tt_swapin(struct ttm_tt *ttm)
 245 {
 246         struct address_space *swap_space;
 247         struct file *swap_storage;
 248         struct page *from_page;
 249         struct page *to_page;
 250         void *from_virtual;
 251         void *to_virtual;
 252         int i;
 253         int ret = -ENOMEM;
 254
 255         swap_storage = ttm->swap_storage;
 256         BUG_ON(swap_storage == NULL);
 257
 258         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 259
 260         for (i = 0; i < ttm->num_pages; ++i) {
 261                 from_page = shmem_read_mapping_page(swap_space, i);
 262                 if (IS_ERR(from_page)) {
 263                         ret = PTR_ERR(from_page);
 264                         goto out_err;
 265                 }
 266                 to_page = ttm->pages[i];
 267                 if (unlikely(to_page == NULL))
 268                         goto out_err;
 269
 270                 preempt_disable();
 271                 from_virtual = kmap_atomic(from_page, KM_USER0);
 272                 to_virtual = kmap_atomic(to_page, KM_USER1);
 273                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 274                 kunmap_atomic(to_virtual, KM_USER1);
 275                 kunmap_atomic(from_virtual, KM_USER0);
 276                 preempt_enable();
 277                 page_cache_release(from_page);
 278         }
 279
 280         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
 281                 fput(swap_storage);
 282         ttm->swap_storage = NULL;
 283         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 284
 285         return 0;
 286 out_err:
 287         return ret;
 288 }
 289
 290 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 291 {
 292         struct address_space *swap_space;
 293         struct file *swap_storage;
 294         struct page *from_page;
 295         struct page *to_page;
 296         void *from_virtual;
 297         void *to_virtual;
 298         int i;
 299         int ret = -ENOMEM;
 300
 301         BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
 302         BUG_ON(ttm->caching_state != tt_cached);
 303
 304         if (!persistent_swap_storage) {
 305                 swap_storage = shmem_file_setup("ttm swap",
 306                                                 ttm->num_pages << PAGE_SHIFT,
 307                                                 0);
 308                 if (unlikely(IS_ERR(swap_storage))) {
 309                         printk(KERN_ERR "Failed allocating swap storage.\n");
 310                         return PTR_ERR(swap_storage);
 311                 }
 312         } else
 313                 swap_storage = persistent_swap_storage;
 314
 315         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 316
 317         for (i = 0; i < ttm->num_pages; ++i) {
 318                 from_page = ttm->pages[i];
 319                 if (unlikely(from_page == NULL))
 320                         continue;
 321                 to_page = shmem_read_mapping_page(swap_space, i);
 322                 if (unlikely(IS_ERR(to_page))) {
 323                         ret = PTR_ERR(to_page);
 324                         goto out_err;
 325                 }
 326                 preempt_disable();
 327                 from_virtual = kmap_atomic(from_page, KM_USER0);
 328                 to_virtual = kmap_atomic(to_page, KM_USER1);
 329                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 330                 kunmap_atomic(to_virtual, KM_USER1);
 331                 kunmap_atomic(from_virtual, KM_USER0);
 332                 preempt_enable();
 333                 set_page_dirty(to_page);
 334                 mark_page_accessed(to_page);
 335                 page_cache_release(to_page);
 336         }
 337
 338         ttm->bdev->driver->ttm_tt_unpopulate(ttm);
 339         ttm->swap_storage = swap_storage;
 340         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 341         if (persistent_swap_storage)
 342                 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
 343
 344         return 0;
 345 out_err:
 346         if (!persistent_swap_storage)
 347                 fput(swap_storage);
 348
 349         return ret;
 350 }