LXR linux/drivers/gpu/drm/ttm/ttm

   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 */
  53static 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
  59static 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
  69static 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 */
  95static 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
 108static 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
 142out_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
 154int 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}
 167EXPORT_SYMBOL(ttm_tt_set_placement_caching);
 168
 169void 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
 187int 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}
 208EXPORT_SYMBOL(ttm_tt_init);
 209
 210void ttm_tt_fini(struct ttm_tt *ttm)
 211{
 212        kvfree(ttm->pages);
 213        ttm->pages = NULL;
 214}
 215EXPORT_SYMBOL(ttm_tt_fini);
 216
 217int 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}
 241EXPORT_SYMBOL(ttm_dma_tt_init);
 242
 243void 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}
 251EXPORT_SYMBOL(ttm_dma_tt_fini);
 252
 253void 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
 264int 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}
 286EXPORT_SYMBOL(ttm_tt_bind);
 287
 288int 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;
 322out_err:
 323        return ret;
 324}
 325
 326int 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;
 373out_err:
 374        if (!persistent_swap_storage)
 375                fput(swap_storage);
 376
 377        return ret;
 378}
 379
 380static 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
 394void 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