git.oblomov.eu Git - linux-2.6/blob - 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/version.h>
  32 #include <linux/vmalloc.h>
  33 #include <linux/sched.h>
  34 #include <linux/highmem.h>
  35 #include <linux/pagemap.h>
  36 #include <linux/file.h>
  37 #include <linux/swap.h>
  38 #include "ttm/ttm_module.h"
  39 #include "ttm/ttm_bo_driver.h"
  40 #include "ttm/ttm_placement.h"
  41
  42 static int ttm_tt_swapin(struct ttm_tt *ttm);
  43
  44 #if defined(CONFIG_X86)
  45 static void ttm_tt_clflush_page(struct page *page)
  46 {
  47         uint8_t *page_virtual;
  48         unsigned int i;
  49
  50         if (unlikely(page == NULL))
  51                 return;
  52
  53         page_virtual = kmap_atomic(page, KM_USER0);
  54
  55         for (i = 0; i < PAGE_SIZE; i += boot_cpu_data.x86_clflush_size)
  56                 clflush(page_virtual + i);
  57
  58         kunmap_atomic(page_virtual, KM_USER0);
  59 }
  60
  61 static void ttm_tt_cache_flush_clflush(struct page *pages[],
  62                                        unsigned long num_pages)
  63 {
  64         unsigned long i;
  65
  66         mb();
  67         for (i = 0; i < num_pages; ++i)
  68                 ttm_tt_clflush_page(*pages++);
  69         mb();
  70 }
  71 #else
  72 static void ttm_tt_ipi_handler(void *null)
  73 {
  74         ;
  75 }
  76 #endif
  77
  78 void ttm_tt_cache_flush(struct page *pages[], unsigned long num_pages)
  79 {
  80
  81 #if defined(CONFIG_X86)
  82         if (cpu_has_clflush) {
  83                 ttm_tt_cache_flush_clflush(pages, num_pages);
  84                 return;
  85         }
  86 #else
  87         if (on_each_cpu(ttm_tt_ipi_handler, NULL, 1) != 0)
  88                 printk(KERN_ERR TTM_PFX
  89                        "Timed out waiting for drm cache flush.\n");
  90 #endif
  91 }
  92
  93 /**
  94  * Allocates storage for pointers to the pages that back the ttm.
  95  *
  96  * Uses kmalloc if possible. Otherwise falls back to vmalloc.
  97  */
  98 static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
  99 {
 100         unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
 101         ttm->pages = NULL;
 102
 103         if (size <= PAGE_SIZE)
 104                 ttm->pages = kzalloc(size, GFP_KERNEL);
 105
 106         if (!ttm->pages) {
 107                 ttm->pages = vmalloc_user(size);
 108                 if (ttm->pages)
 109                         ttm->page_flags |= TTM_PAGE_FLAG_VMALLOC;
 110         }
 111 }
 112
 113 static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
 114 {
 115         if (ttm->page_flags & TTM_PAGE_FLAG_VMALLOC) {
 116                 vfree(ttm->pages);
 117                 ttm->page_flags &= ~TTM_PAGE_FLAG_VMALLOC;
 118         } else {
 119                 kfree(ttm->pages);
 120         }
 121         ttm->pages = NULL;
 122 }
 123
 124 static struct page *ttm_tt_alloc_page(unsigned page_flags)
 125 {
 126         if (page_flags & TTM_PAGE_FLAG_ZERO_ALLOC)
 127                 return alloc_page(GFP_HIGHUSER | __GFP_ZERO);
 128
 129         return alloc_page(GFP_HIGHUSER);
 130 }
 131
 132 static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
 133 {
 134         int write;
 135         int dirty;
 136         struct page *page;
 137         int i;
 138         struct ttm_backend *be = ttm->be;
 139
 140         BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER));
 141         write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0);
 142         dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0);
 143
 144         if (be)
 145                 be->func->clear(be);
 146
 147         for (i = 0; i < ttm->num_pages; ++i) {
 148                 page = ttm->pages[i];
 149                 if (page == NULL)
 150                         continue;
 151
 152                 if (page == ttm->dummy_read_page) {
 153                         BUG_ON(write);
 154                         continue;
 155                 }
 156
 157                 if (write && dirty && !PageReserved(page))
 158                         set_page_dirty_lock(page);
 159
 160                 ttm->pages[i] = NULL;
 161                 ttm_mem_global_free(ttm->bdev->mem_glob, PAGE_SIZE, false);
 162                 put_page(page);
 163         }
 164         ttm->state = tt_unpopulated;
 165         ttm->first_himem_page = ttm->num_pages;
 166         ttm->last_lomem_page = -1;
 167 }
 168
 169 static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index)
 170 {
 171         struct page *p;
 172         struct ttm_bo_device *bdev = ttm->bdev;
 173         struct ttm_mem_global *mem_glob = bdev->mem_glob;
 174         int ret;
 175
 176         while (NULL == (p = ttm->pages[index])) {
 177                 p = ttm_tt_alloc_page(ttm->page_flags);
 178
 179                 if (!p)
 180                         return NULL;
 181
 182                 if (PageHighMem(p)) {
 183                         ret =
 184                             ttm_mem_global_alloc(mem_glob, PAGE_SIZE,
 185                                                  false, false, true);
 186                         if (unlikely(ret != 0))
 187                                 goto out_err;
 188                         ttm->pages[--ttm->first_himem_page] = p;
 189                 } else {
 190                         ret =
 191                             ttm_mem_global_alloc(mem_glob, PAGE_SIZE,
 192                                                  false, false, false);
 193                         if (unlikely(ret != 0))
 194                                 goto out_err;
 195                         ttm->pages[++ttm->last_lomem_page] = p;
 196                 }
 197         }
 198         return p;
 199 out_err:
 200         put_page(p);
 201         return NULL;
 202 }
 203
 204 struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index)
 205 {
 206         int ret;
 207
 208         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
 209                 ret = ttm_tt_swapin(ttm);
 210                 if (unlikely(ret != 0))
 211                         return NULL;
 212         }
 213         return __ttm_tt_get_page(ttm, index);
 214 }
 215
 216 int ttm_tt_populate(struct ttm_tt *ttm)
 217 {
 218         struct page *page;
 219         unsigned long i;
 220         struct ttm_backend *be;
 221         int ret;
 222
 223         if (ttm->state != tt_unpopulated)
 224                 return 0;
 225
 226         if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
 227                 ret = ttm_tt_swapin(ttm);
 228                 if (unlikely(ret != 0))
 229                         return ret;
 230         }
 231
 232         be = ttm->be;
 233
 234         for (i = 0; i < ttm->num_pages; ++i) {
 235                 page = __ttm_tt_get_page(ttm, i);
 236                 if (!page)
 237                         return -ENOMEM;
 238         }
 239
 240         be->func->populate(be, ttm->num_pages, ttm->pages,
 241                            ttm->dummy_read_page);
 242         ttm->state = tt_unbound;
 243         return 0;
 244 }
 245
 246 #ifdef CONFIG_X86
 247 static inline int ttm_tt_set_page_caching(struct page *p,
 248                                           enum ttm_caching_state c_state)
 249 {
 250         if (PageHighMem(p))
 251                 return 0;
 252
 253         switch (c_state) {
 254         case tt_cached:
 255                 return set_pages_wb(p, 1);
 256         case tt_wc:
 257             return set_memory_wc((unsigned long) page_address(p), 1);
 258         default:
 259                 return set_pages_uc(p, 1);
 260         }
 261 }
 262 #else /* CONFIG_X86 */
 263 static inline int ttm_tt_set_page_caching(struct page *p,
 264                                           enum ttm_caching_state c_state)
 265 {
 266         return 0;
 267 }
 268 #endif /* CONFIG_X86 */
 269
 270 /*
 271  * Change caching policy for the linear kernel map
 272  * for range of pages in a ttm.
 273  */
 274
 275 static int ttm_tt_set_caching(struct ttm_tt *ttm,
 276                               enum ttm_caching_state c_state)
 277 {
 278         int i, j;
 279         struct page *cur_page;
 280         int ret;
 281
 282         if (ttm->caching_state == c_state)
 283                 return 0;
 284
 285         if (c_state != tt_cached) {
 286                 ret = ttm_tt_populate(ttm);
 287                 if (unlikely(ret != 0))
 288                         return ret;
 289         }
 290
 291         if (ttm->caching_state == tt_cached)
 292                 ttm_tt_cache_flush(ttm->pages, ttm->num_pages);
 293
 294         for (i = 0; i < ttm->num_pages; ++i) {
 295                 cur_page = ttm->pages[i];
 296                 if (likely(cur_page != NULL)) {
 297                         ret = ttm_tt_set_page_caching(cur_page, c_state);
 298                         if (unlikely(ret != 0))
 299                                 goto out_err;
 300                 }
 301         }
 302
 303         ttm->caching_state = c_state;
 304
 305         return 0;
 306
 307 out_err:
 308         for (j = 0; j < i; ++j) {
 309                 cur_page = ttm->pages[j];
 310                 if (likely(cur_page != NULL)) {
 311                         (void)ttm_tt_set_page_caching(cur_page,
 312                                                       ttm->caching_state);
 313                 }
 314         }
 315
 316         return ret;
 317 }
 318
 319 int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
 320 {
 321         enum ttm_caching_state state;
 322
 323         if (placement & TTM_PL_FLAG_WC)
 324                 state = tt_wc;
 325         else if (placement & TTM_PL_FLAG_UNCACHED)
 326                 state = tt_uncached;
 327         else
 328                 state = tt_cached;
 329
 330         return ttm_tt_set_caching(ttm, state);
 331 }
 332
 333 static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
 334 {
 335         int i;
 336         struct page *cur_page;
 337         struct ttm_backend *be = ttm->be;
 338
 339         if (be)
 340                 be->func->clear(be);
 341         (void)ttm_tt_set_caching(ttm, tt_cached);
 342         for (i = 0; i < ttm->num_pages; ++i) {
 343                 cur_page = ttm->pages[i];
 344                 ttm->pages[i] = NULL;
 345                 if (cur_page) {
 346                         if (page_count(cur_page) != 1)
 347                                 printk(KERN_ERR TTM_PFX
 348                                        "Erroneous page count. "
 349                                        "Leaking pages.\n");
 350                         ttm_mem_global_free(ttm->bdev->mem_glob, PAGE_SIZE,
 351                                             PageHighMem(cur_page));
 352                         __free_page(cur_page);
 353                 }
 354         }
 355         ttm->state = tt_unpopulated;
 356         ttm->first_himem_page = ttm->num_pages;
 357         ttm->last_lomem_page = -1;
 358 }
 359
 360 void ttm_tt_destroy(struct ttm_tt *ttm)
 361 {
 362         struct ttm_backend *be;
 363
 364         if (unlikely(ttm == NULL))
 365                 return;
 366
 367         be = ttm->be;
 368         if (likely(be != NULL)) {
 369                 be->func->destroy(be);
 370                 ttm->be = NULL;
 371         }
 372
 373         if (likely(ttm->pages != NULL)) {
 374                 if (ttm->page_flags & TTM_PAGE_FLAG_USER)
 375                         ttm_tt_free_user_pages(ttm);
 376                 else
 377                         ttm_tt_free_alloced_pages(ttm);
 378
 379                 ttm_tt_free_page_directory(ttm);
 380         }
 381
 382         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) &&
 383             ttm->swap_storage)
 384                 fput(ttm->swap_storage);
 385
 386         kfree(ttm);
 387 }
 388
 389 int ttm_tt_set_user(struct ttm_tt *ttm,
 390                     struct task_struct *tsk,
 391                     unsigned long start, unsigned long num_pages)
 392 {
 393         struct mm_struct *mm = tsk->mm;
 394         int ret;
 395         int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
 396         struct ttm_mem_global *mem_glob = ttm->bdev->mem_glob;
 397
 398         BUG_ON(num_pages != ttm->num_pages);
 399         BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);
 400
 401         /**
 402          * Account user pages as lowmem pages for now.
 403          */
 404
 405         ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE,
 406                                    false, false, false);
 407         if (unlikely(ret != 0))
 408                 return ret;
 409
 410         down_read(&mm->mmap_sem);
 411         ret = get_user_pages(tsk, mm, start, num_pages,
 412                              write, 0, ttm->pages, NULL);
 413         up_read(&mm->mmap_sem);
 414
 415         if (ret != num_pages && write) {
 416                 ttm_tt_free_user_pages(ttm);
 417                 ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE, false);
 418                 return -ENOMEM;
 419         }
 420
 421         ttm->tsk = tsk;
 422         ttm->start = start;
 423         ttm->state = tt_unbound;
 424
 425         return 0;
 426 }
 427
 428 struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size,
 429                              uint32_t page_flags, struct page *dummy_read_page)
 430 {
 431         struct ttm_bo_driver *bo_driver = bdev->driver;
 432         struct ttm_tt *ttm;
 433
 434         if (!bo_driver)
 435                 return NULL;
 436
 437         ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
 438         if (!ttm)
 439                 return NULL;
 440
 441         ttm->bdev = bdev;
 442
 443         ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
 444         ttm->first_himem_page = ttm->num_pages;
 445         ttm->last_lomem_page = -1;
 446         ttm->caching_state = tt_cached;
 447         ttm->page_flags = page_flags;
 448
 449         ttm->dummy_read_page = dummy_read_page;
 450
 451         ttm_tt_alloc_page_directory(ttm);
 452         if (!ttm->pages) {
 453                 ttm_tt_destroy(ttm);
 454                 printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
 455                 return NULL;
 456         }
 457         ttm->be = bo_driver->create_ttm_backend_entry(bdev);
 458         if (!ttm->be) {
 459                 ttm_tt_destroy(ttm);
 460                 printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
 461                 return NULL;
 462         }
 463         ttm->state = tt_unpopulated;
 464         return ttm;
 465 }
 466
 467 void ttm_tt_unbind(struct ttm_tt *ttm)
 468 {
 469         int ret;
 470         struct ttm_backend *be = ttm->be;
 471
 472         if (ttm->state == tt_bound) {
 473                 ret = be->func->unbind(be);
 474                 BUG_ON(ret);
 475                 ttm->state = tt_unbound;
 476         }
 477 }
 478
 479 int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
 480 {
 481         int ret = 0;
 482         struct ttm_backend *be;
 483
 484         if (!ttm)
 485                 return -EINVAL;
 486
 487         if (ttm->state == tt_bound)
 488                 return 0;
 489
 490         be = ttm->be;
 491
 492         ret = ttm_tt_populate(ttm);
 493         if (ret)
 494                 return ret;
 495
 496         ret = be->func->bind(be, bo_mem);
 497         if (ret) {
 498                 printk(KERN_ERR TTM_PFX "Couldn't bind backend.\n");
 499                 return ret;
 500         }
 501
 502         ttm->state = tt_bound;
 503
 504         if (ttm->page_flags & TTM_PAGE_FLAG_USER)
 505                 ttm->page_flags |= TTM_PAGE_FLAG_USER_DIRTY;
 506         return 0;
 507 }
 508 EXPORT_SYMBOL(ttm_tt_bind);
 509
 510 static int ttm_tt_swapin(struct ttm_tt *ttm)
 511 {
 512         struct address_space *swap_space;
 513         struct file *swap_storage;
 514         struct page *from_page;
 515         struct page *to_page;
 516         void *from_virtual;
 517         void *to_virtual;
 518         int i;
 519         int ret;
 520
 521         if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
 522                 ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start,
 523                                       ttm->num_pages);
 524                 if (unlikely(ret != 0))
 525                         return ret;
 526
 527                 ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 528                 return 0;
 529         }
 530
 531         swap_storage = ttm->swap_storage;
 532         BUG_ON(swap_storage == NULL);
 533
 534         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 535
 536         for (i = 0; i < ttm->num_pages; ++i) {
 537                 from_page = read_mapping_page(swap_space, i, NULL);
 538                 if (IS_ERR(from_page))
 539                         goto out_err;
 540                 to_page = __ttm_tt_get_page(ttm, i);
 541                 if (unlikely(to_page == NULL))
 542                         goto out_err;
 543
 544                 preempt_disable();
 545                 from_virtual = kmap_atomic(from_page, KM_USER0);
 546                 to_virtual = kmap_atomic(to_page, KM_USER1);
 547                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 548                 kunmap_atomic(to_virtual, KM_USER1);
 549                 kunmap_atomic(from_virtual, KM_USER0);
 550                 preempt_enable();
 551                 page_cache_release(from_page);
 552         }
 553
 554         if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP))
 555                 fput(swap_storage);
 556         ttm->swap_storage = NULL;
 557         ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
 558
 559         return 0;
 560 out_err:
 561         ttm_tt_free_alloced_pages(ttm);
 562         return -ENOMEM;
 563 }
 564
 565 int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistant_swap_storage)
 566 {
 567         struct address_space *swap_space;
 568         struct file *swap_storage;
 569         struct page *from_page;
 570         struct page *to_page;
 571         void *from_virtual;
 572         void *to_virtual;
 573         int i;
 574
 575         BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
 576         BUG_ON(ttm->caching_state != tt_cached);
 577
 578         /*
 579          * For user buffers, just unpin the pages, as there should be
 580          * vma references.
 581          */
 582
 583         if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
 584                 ttm_tt_free_user_pages(ttm);
 585                 ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 586                 ttm->swap_storage = NULL;
 587                 return 0;
 588         }
 589
 590         if (!persistant_swap_storage) {
 591                 swap_storage = shmem_file_setup("ttm swap",
 592                                                 ttm->num_pages << PAGE_SHIFT,
 593                                                 0);
 594                 if (unlikely(IS_ERR(swap_storage))) {
 595                         printk(KERN_ERR "Failed allocating swap storage.\n");
 596                         return -ENOMEM;
 597                 }
 598         } else
 599                 swap_storage = persistant_swap_storage;
 600
 601         swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
 602
 603         for (i = 0; i < ttm->num_pages; ++i) {
 604                 from_page = ttm->pages[i];
 605                 if (unlikely(from_page == NULL))
 606                         continue;
 607                 to_page = read_mapping_page(swap_space, i, NULL);
 608                 if (unlikely(to_page == NULL))
 609                         goto out_err;
 610
 611                 preempt_disable();
 612                 from_virtual = kmap_atomic(from_page, KM_USER0);
 613                 to_virtual = kmap_atomic(to_page, KM_USER1);
 614                 memcpy(to_virtual, from_virtual, PAGE_SIZE);
 615                 kunmap_atomic(to_virtual, KM_USER1);
 616                 kunmap_atomic(from_virtual, KM_USER0);
 617                 preempt_enable();
 618                 set_page_dirty(to_page);
 619                 mark_page_accessed(to_page);
 620                 page_cache_release(to_page);
 621         }
 622
 623         ttm_tt_free_alloced_pages(ttm);
 624         ttm->swap_storage = swap_storage;
 625         ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 626         if (persistant_swap_storage)
 627                 ttm->page_flags |= TTM_PAGE_FLAG_PERSISTANT_SWAP;
 628
 629         return 0;
 630 out_err:
 631         if (!persistant_swap_storage)
 632                 fput(swap_storage);
 633
 634         return -ENOMEM;
 635 }