drivers/gpu/drm/drm_mm.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., 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
  29 /*
  30  * Generic simple memory manager implementation. Intended to be used as a base
  31  * class implementation for more advanced memory managers.
  32  *
  33  * Note that the algorithm used is quite simple and there might be substantial
  34  * performance gains if a smarter free list is implemented. Currently it is just an
  35  * unordered stack of free regions. This could easily be improved if an RB-tree
  36  * is used instead. At least if we expect heavy fragmentation.
  37  *
  38  * Aligned allocations can also see improvement.
  39  *
  40  * Authors:
  41  * Thomas Hellström <thomas-at-tungstengraphics-dot-com>
  42  */
  43
  44 #include <drm/drmP.h>
  45 #include <drm/drm_mm.h>
  46 #include <linux/slab.h>
  47 #include <linux/seq_file.h>
  48 #include <linux/export.h>
  49
  50 #define MM_UNUSED_TARGET 4
  51
  52 static struct drm_mm_node *drm_mm_kmalloc(struct drm_mm *mm, int atomic)
  53 {
  54         struct drm_mm_node *child;
  55
  56         if (atomic)
  57                 child = kzalloc(sizeof(*child), GFP_ATOMIC);
  58         else
  59                 child = kzalloc(sizeof(*child), GFP_KERNEL);
  60
  61         if (unlikely(child == NULL)) {
  62                 spin_lock(&mm->unused_lock);
  63                 if (list_empty(&mm->unused_nodes))
  64                         child = NULL;
  65                 else {
  66                         child =
  67                             list_entry(mm->unused_nodes.next,
  68                                        struct drm_mm_node, node_list);
  69                         list_del(&child->node_list);
  70                         --mm->num_unused;
  71                 }
  72                 spin_unlock(&mm->unused_lock);
  73         }
  74         return child;
  75 }
  76
  77 /* drm_mm_pre_get() - pre allocate drm_mm_node structure
  78  * drm_mm:      memory manager struct we are pre-allocating for
  79  *
  80  * Returns 0 on success or -ENOMEM if allocation fails.
  81  */
  82 int drm_mm_pre_get(struct drm_mm *mm)
  83 {
  84         struct drm_mm_node *node;
  85
  86         spin_lock(&mm->unused_lock);
  87         while (mm->num_unused < MM_UNUSED_TARGET) {
  88                 spin_unlock(&mm->unused_lock);
  89                 node = kzalloc(sizeof(*node), GFP_KERNEL);
  90                 spin_lock(&mm->unused_lock);
  91
  92                 if (unlikely(node == NULL)) {
  93                         int ret = (mm->num_unused < 2) ? -ENOMEM : 0;
  94                         spin_unlock(&mm->unused_lock);
  95                         return ret;
  96                 }
  97                 ++mm->num_unused;
  98                 list_add_tail(&node->node_list, &mm->unused_nodes);
  99         }
 100         spin_unlock(&mm->unused_lock);
 101         return 0;
 102 }
 103 EXPORT_SYMBOL(drm_mm_pre_get);
 104
 105 static inline unsigned long drm_mm_hole_node_start(struct drm_mm_node *hole_node)
 106 {
 107         return hole_node->start + hole_node->size;
 108 }
 109
 110 static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node)
 111 {
 112         struct drm_mm_node *next_node =
 113                 list_entry(hole_node->node_list.next, struct drm_mm_node,
 114                            node_list);
 115
 116         return next_node->start;
 117 }
 118
 119 static void drm_mm_insert_helper(struct drm_mm_node *hole_node,
 120                                  struct drm_mm_node *node,
 121                                  unsigned long size, unsigned alignment,
 122                                  unsigned long color)
 123 {
 124         struct drm_mm *mm = hole_node->mm;
 125         unsigned long hole_start = drm_mm_hole_node_start(hole_node);
 126         unsigned long hole_end = drm_mm_hole_node_end(hole_node);
 127         unsigned long adj_start = hole_start;
 128         unsigned long adj_end = hole_end;
 129
 130         BUG_ON(!hole_node->hole_follows || node->allocated);
 131
 132         if (mm->color_adjust)
 133                 mm->color_adjust(hole_node, color, &adj_start, &adj_end);
 134
 135         if (alignment) {
 136                 unsigned tmp = adj_start % alignment;
 137                 if (tmp)
 138                         adj_start += alignment - tmp;
 139         }
 140
 141         if (adj_start == hole_start) {
 142                 hole_node->hole_follows = 0;
 143                 list_del(&hole_node->hole_stack);
 144         }
 145
 146         node->start = adj_start;
 147         node->size = size;
 148         node->mm = mm;
 149         node->color = color;
 150         node->allocated = 1;
 151
 152         INIT_LIST_HEAD(&node->hole_stack);
 153         list_add(&node->node_list, &hole_node->node_list);
 154
 155         BUG_ON(node->start + node->size > adj_end);
 156
 157         node->hole_follows = 0;
 158         if (node->start + node->size < hole_end) {
 159                 list_add(&node->hole_stack, &mm->hole_stack);
 160                 node->hole_follows = 1;
 161         }
 162 }
 163
 164 struct drm_mm_node *drm_mm_get_block_generic(struct drm_mm_node *hole_node,
 165                                              unsigned long size,
 166                                              unsigned alignment,
 167                                              unsigned long color,
 168                                              int atomic)
 169 {
 170         struct drm_mm_node *node;
 171
 172         node = drm_mm_kmalloc(hole_node->mm, atomic);
 173         if (unlikely(node == NULL))
 174                 return NULL;
 175
 176         drm_mm_insert_helper(hole_node, node, size, alignment, color);
 177
 178         return node;
 179 }
 180 EXPORT_SYMBOL(drm_mm_get_block_generic);
 181
 182 /**
 183  * Search for free space and insert a preallocated memory node. Returns
 184  * -ENOSPC if no suitable free area is available. The preallocated memory node
 185  * must be cleared.
 186  */
 187 int drm_mm_insert_node(struct drm_mm *mm, struct drm_mm_node *node,
 188                        unsigned long size, unsigned alignment)
 189 {
 190         struct drm_mm_node *hole_node;
 191
 192         hole_node = drm_mm_search_free(mm, size, alignment, false);
 193         if (!hole_node)
 194                 return -ENOSPC;
 195
 196         drm_mm_insert_helper(hole_node, node, size, alignment, 0);
 197
 198         return 0;
 199 }
 200 EXPORT_SYMBOL(drm_mm_insert_node);
 201
 202 static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node,
 203                                        struct drm_mm_node *node,
 204                                        unsigned long size, unsigned alignment,
 205                                        unsigned long color,
 206                                        unsigned long start, unsigned long end)
 207 {
 208         struct drm_mm *mm = hole_node->mm;
 209         unsigned long hole_start = drm_mm_hole_node_start(hole_node);
 210         unsigned long hole_end = drm_mm_hole_node_end(hole_node);
 211         unsigned long adj_start = hole_start;
 212         unsigned long adj_end = hole_end;
 213
 214         BUG_ON(!hole_node->hole_follows || node->allocated);
 215
 216         if (mm->color_adjust)
 217                 mm->color_adjust(hole_node, color, &adj_start, &adj_end);
 218
 219         if (adj_start < start)
 220                 adj_start = start;
 221
 222         if (alignment) {
 223                 unsigned tmp = adj_start % alignment;
 224                 if (tmp)
 225                         adj_start += alignment - tmp;
 226         }
 227
 228         if (adj_start == hole_start) {
 229                 hole_node->hole_follows = 0;
 230                 list_del(&hole_node->hole_stack);
 231         }
 232
 233         node->start = adj_start;
 234         node->size = size;
 235         node->mm = mm;
 236         node->color = color;
 237         node->allocated = 1;
 238
 239         INIT_LIST_HEAD(&node->hole_stack);
 240         list_add(&node->node_list, &hole_node->node_list);
 241
 242         BUG_ON(node->start + node->size > adj_end);
 243         BUG_ON(node->start + node->size > end);
 244
 245         node->hole_follows = 0;
 246         if (node->start + node->size < hole_end) {
 247                 list_add(&node->hole_stack, &mm->hole_stack);
 248                 node->hole_follows = 1;
 249         }
 250 }
 251
 252 struct drm_mm_node *drm_mm_get_block_range_generic(struct drm_mm_node *hole_node,
 253                                                 unsigned long size,
 254                                                 unsigned alignment,
 255                                                 unsigned long color,
 256                                                 unsigned long start,
 257                                                 unsigned long end,
 258                                                 int atomic)
 259 {
 260         struct drm_mm_node *node;
 261
 262         node = drm_mm_kmalloc(hole_node->mm, atomic);
 263         if (unlikely(node == NULL))
 264                 return NULL;
 265
 266         drm_mm_insert_helper_range(hole_node, node, size, alignment, color,
 267                                    start, end);
 268
 269         return node;
 270 }
 271 EXPORT_SYMBOL(drm_mm_get_block_range_generic);
 272
 273 /**
 274  * Search for free space and insert a preallocated memory node. Returns
 275  * -ENOSPC if no suitable free area is available. This is for range
 276  * restricted allocations. The preallocated memory node must be cleared.
 277  */
 278 int drm_mm_insert_node_in_range(struct drm_mm *mm, struct drm_mm_node *node,
 279                                 unsigned long size, unsigned alignment,
 280                                 unsigned long start, unsigned long end)
 281 {
 282         struct drm_mm_node *hole_node;
 283
 284         hole_node = drm_mm_search_free_in_range(mm, size, alignment,
 285                                                 start, end, false);
 286         if (!hole_node)
 287                 return -ENOSPC;
 288
 289         drm_mm_insert_helper_range(hole_node, node, size, alignment, 0,
 290                                    start, end);
 291
 292         return 0;
 293 }
 294 EXPORT_SYMBOL(drm_mm_insert_node_in_range);
 295
 296 /**
 297  * Remove a memory node from the allocator.
 298  */
 299 void drm_mm_remove_node(struct drm_mm_node *node)
 300 {
 301         struct drm_mm *mm = node->mm;
 302         struct drm_mm_node *prev_node;
 303
 304         BUG_ON(node->scanned_block || node->scanned_prev_free
 305                                    || node->scanned_next_free);
 306
 307         prev_node =
 308             list_entry(node->node_list.prev, struct drm_mm_node, node_list);
 309
 310         if (node->hole_follows) {
 311                 BUG_ON(drm_mm_hole_node_start(node)
 312                                 == drm_mm_hole_node_end(node));
 313                 list_del(&node->hole_stack);
 314         } else
 315                 BUG_ON(drm_mm_hole_node_start(node)
 316                                 != drm_mm_hole_node_end(node));
 317
 318         if (!prev_node->hole_follows) {
 319                 prev_node->hole_follows = 1;
 320                 list_add(&prev_node->hole_stack, &mm->hole_stack);
 321         } else
 322                 list_move(&prev_node->hole_stack, &mm->hole_stack);
 323
 324         list_del(&node->node_list);
 325         node->allocated = 0;
 326 }
 327 EXPORT_SYMBOL(drm_mm_remove_node);
 328
 329 /*
 330  * Remove a memory node from the allocator and free the allocated struct
 331  * drm_mm_node. Only to be used on a struct drm_mm_node obtained by one of the
 332  * drm_mm_get_block functions.
 333  */
 334 void drm_mm_put_block(struct drm_mm_node *node)
 335 {
 336
 337         struct drm_mm *mm = node->mm;
 338
 339         drm_mm_remove_node(node);
 340
 341         spin_lock(&mm->unused_lock);
 342         if (mm->num_unused < MM_UNUSED_TARGET) {
 343                 list_add(&node->node_list, &mm->unused_nodes);
 344                 ++mm->num_unused;
 345         } else
 346                 kfree(node);
 347         spin_unlock(&mm->unused_lock);
 348 }
 349 EXPORT_SYMBOL(drm_mm_put_block);
 350
 351 static int check_free_hole(unsigned long start, unsigned long end,
 352                            unsigned long size, unsigned alignment)
 353 {
 354         if (end - start < size)
 355                 return 0;
 356
 357         if (alignment) {
 358                 unsigned tmp = start % alignment;
 359                 if (tmp)
 360                         start += alignment - tmp;
 361         }
 362
 363         return end >= start + size;
 364 }
 365
 366 struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm,
 367                                                unsigned long size,
 368                                                unsigned alignment,
 369                                                unsigned long color,
 370                                                bool best_match)
 371 {
 372         struct drm_mm_node *entry;
 373         struct drm_mm_node *best;
 374         unsigned long best_size;
 375
 376         BUG_ON(mm->scanned_blocks);
 377
 378         best = NULL;
 379         best_size = ~0UL;
 380
 381         list_for_each_entry(entry, &mm->hole_stack, hole_stack) {
 382                 unsigned long adj_start = drm_mm_hole_node_start(entry);
 383                 unsigned long adj_end = drm_mm_hole_node_end(entry);
 384
 385                 if (mm->color_adjust) {
 386                         mm->color_adjust(entry, color, &adj_start, &adj_end);
 387                         if (adj_end <= adj_start)
 388                                 continue;
 389                 }
 390
 391                 BUG_ON(!entry->hole_follows);
 392                 if (!check_free_hole(adj_start, adj_end, size, alignment))
 393                         continue;
 394
 395                 if (!best_match)
 396                         return entry;
 397
 398                 if (entry->size < best_size) {
 399                         best = entry;
 400                         best_size = entry->size;
 401                 }
 402         }
 403
 404         return best;
 405 }
 406 EXPORT_SYMBOL(drm_mm_search_free_generic);
 407
 408 struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm,
 409                                                         unsigned long size,
 410                                                         unsigned alignment,
 411                                                         unsigned long color,
 412                                                         unsigned long start,
 413                                                         unsigned long end,
 414                                                         bool best_match)
 415 {
 416         struct drm_mm_node *entry;
 417         struct drm_mm_node *best;
 418         unsigned long best_size;
 419
 420         BUG_ON(mm->scanned_blocks);
 421
 422         best = NULL;
 423         best_size = ~0UL;
 424
 425         list_for_each_entry(entry, &mm->hole_stack, hole_stack) {
 426                 unsigned long adj_start = drm_mm_hole_node_start(entry) < start ?
 427                         start : drm_mm_hole_node_start(entry);
 428                 unsigned long adj_end = drm_mm_hole_node_end(entry) > end ?
 429                         end : drm_mm_hole_node_end(entry);
 430
 431                 BUG_ON(!entry->hole_follows);
 432
 433                 if (mm->color_adjust) {
 434                         mm->color_adjust(entry, color, &adj_start, &adj_end);
 435                         if (adj_end <= adj_start)
 436                                 continue;
 437                 }
 438
 439                 if (!check_free_hole(adj_start, adj_end, size, alignment))
 440                         continue;
 441
 442                 if (!best_match)
 443                         return entry;
 444
 445                 if (entry->size < best_size) {
 446                         best = entry;
 447                         best_size = entry->size;
 448                 }
 449         }
 450
 451         return best;
 452 }
 453 EXPORT_SYMBOL(drm_mm_search_free_in_range_generic);
 454
 455 /**
 456  * Moves an allocation. To be used with embedded struct drm_mm_node.
 457  */
 458 void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new)
 459 {
 460         list_replace(&old->node_list, &new->node_list);
 461         list_replace(&old->hole_stack, &new->hole_stack);
 462         new->hole_follows = old->hole_follows;
 463         new->mm = old->mm;
 464         new->start = old->start;
 465         new->size = old->size;
 466         new->color = old->color;
 467
 468         old->allocated = 0;
 469         new->allocated = 1;
 470 }
 471 EXPORT_SYMBOL(drm_mm_replace_node);
 472
 473 /**
 474  * Initializa lru scanning.
 475  *
 476  * This simply sets up the scanning routines with the parameters for the desired
 477  * hole.
 478  *
 479  * Warning: As long as the scan list is non-empty, no other operations than
 480  * adding/removing nodes to/from the scan list are allowed.
 481  */
 482 void drm_mm_init_scan(struct drm_mm *mm,
 483                       unsigned long size,
 484                       unsigned alignment,
 485                       unsigned long color)
 486 {
 487         mm->scan_color = color;
 488         mm->scan_alignment = alignment;
 489         mm->scan_size = size;
 490         mm->scanned_blocks = 0;
 491         mm->scan_hit_start = 0;
 492         mm->scan_hit_size = 0;
 493         mm->scan_check_range = 0;
 494         mm->prev_scanned_node = NULL;
 495 }
 496 EXPORT_SYMBOL(drm_mm_init_scan);
 497
 498 /**
 499  * Initializa lru scanning.
 500  *
 501  * This simply sets up the scanning routines with the parameters for the desired
 502  * hole. This version is for range-restricted scans.
 503  *
 504  * Warning: As long as the scan list is non-empty, no other operations than
 505  * adding/removing nodes to/from the scan list are allowed.
 506  */
 507 void drm_mm_init_scan_with_range(struct drm_mm *mm,
 508                                  unsigned long size,
 509                                  unsigned alignment,
 510                                  unsigned long color,
 511                                  unsigned long start,
 512                                  unsigned long end)
 513 {
 514         mm->scan_color = color;
 515         mm->scan_alignment = alignment;
 516         mm->scan_size = size;
 517         mm->scanned_blocks = 0;
 518         mm->scan_hit_start = 0;
 519         mm->scan_hit_size = 0;
 520         mm->scan_start = start;
 521         mm->scan_end = end;
 522         mm->scan_check_range = 1;
 523         mm->prev_scanned_node = NULL;
 524 }
 525 EXPORT_SYMBOL(drm_mm_init_scan_with_range);
 526
 527 /**
 528  * Add a node to the scan list that might be freed to make space for the desired
 529  * hole.
 530  *
 531  * Returns non-zero, if a hole has been found, zero otherwise.
 532  */
 533 int drm_mm_scan_add_block(struct drm_mm_node *node)
 534 {
 535         struct drm_mm *mm = node->mm;
 536         struct drm_mm_node *prev_node;
 537         unsigned long hole_start, hole_end;
 538         unsigned long adj_start;
 539         unsigned long adj_end;
 540
 541         mm->scanned_blocks++;
 542
 543         BUG_ON(node->scanned_block);
 544         node->scanned_block = 1;
 545
 546         prev_node = list_entry(node->node_list.prev, struct drm_mm_node,
 547                                node_list);
 548
 549         node->scanned_preceeds_hole = prev_node->hole_follows;
 550         prev_node->hole_follows = 1;
 551         list_del(&node->node_list);
 552         node->node_list.prev = &prev_node->node_list;
 553         node->node_list.next = &mm->prev_scanned_node->node_list;
 554         mm->prev_scanned_node = node;
 555
 556         hole_start = drm_mm_hole_node_start(prev_node);
 557         hole_end = drm_mm_hole_node_end(prev_node);
 558
 559         adj_start = hole_start;
 560         adj_end = hole_end;
 561
 562         if (mm->color_adjust)
 563                 mm->color_adjust(prev_node, mm->scan_color, &adj_start, &adj_end);
 564
 565         if (mm->scan_check_range) {
 566                 if (adj_start < mm->scan_start)
 567                         adj_start = mm->scan_start;
 568                 if (adj_end > mm->scan_end)
 569                         adj_end = mm->scan_end;
 570         }
 571
 572         if (check_free_hole(adj_start, adj_end,
 573                             mm->scan_size, mm->scan_alignment)) {
 574                 mm->scan_hit_start = hole_start;
 575                 mm->scan_hit_size = hole_end;
 576
 577                 return 1;
 578         }
 579
 580         return 0;
 581 }
 582 EXPORT_SYMBOL(drm_mm_scan_add_block);
 583
 584 /**
 585  * Remove a node from the scan list.
 586  *
 587  * Nodes _must_ be removed in the exact same order from the scan list as they
 588  * have been added, otherwise the internal state of the memory manager will be
 589  * corrupted.
 590  *
 591  * When the scan list is empty, the selected memory nodes can be freed. An
 592  * immediately following drm_mm_search_free with best_match = 0 will then return
 593  * the just freed block (because its at the top of the free_stack list).
 594  *
 595  * Returns one if this block should be evicted, zero otherwise. Will always
 596  * return zero when no hole has been found.
 597  */
 598 int drm_mm_scan_remove_block(struct drm_mm_node *node)
 599 {
 600         struct drm_mm *mm = node->mm;
 601         struct drm_mm_node *prev_node;
 602
 603         mm->scanned_blocks--;
 604
 605         BUG_ON(!node->scanned_block);
 606         node->scanned_block = 0;
 607
 608         prev_node = list_entry(node->node_list.prev, struct drm_mm_node,
 609                                node_list);
 610
 611         prev_node->hole_follows = node->scanned_preceeds_hole;
 612         INIT_LIST_HEAD(&node->node_list);
 613         list_add(&node->node_list, &prev_node->node_list);
 614
 615         /* Only need to check for containement because start&size for the
 616          * complete resulting free block (not just the desired part) is
 617          * stored. */
 618         if (node->start >= mm->scan_hit_start &&
 619             node->start + node->size
 620                         <= mm->scan_hit_start + mm->scan_hit_size) {
 621                 return 1;
 622         }
 623
 624         return 0;
 625 }
 626 EXPORT_SYMBOL(drm_mm_scan_remove_block);
 627
 628 int drm_mm_clean(struct drm_mm * mm)
 629 {
 630         struct list_head *head = &mm->head_node.node_list;
 631
 632         return (head->next->next == head);
 633 }
 634 EXPORT_SYMBOL(drm_mm_clean);
 635
 636 int drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size)
 637 {
 638         INIT_LIST_HEAD(&mm->hole_stack);
 639         INIT_LIST_HEAD(&mm->unused_nodes);
 640         mm->num_unused = 0;
 641         mm->scanned_blocks = 0;
 642         spin_lock_init(&mm->unused_lock);
 643
 644         /* Clever trick to avoid a special case in the free hole tracking. */
 645         INIT_LIST_HEAD(&mm->head_node.node_list);
 646         INIT_LIST_HEAD(&mm->head_node.hole_stack);
 647         mm->head_node.hole_follows = 1;
 648         mm->head_node.scanned_block = 0;
 649         mm->head_node.scanned_prev_free = 0;
 650         mm->head_node.scanned_next_free = 0;
 651         mm->head_node.mm = mm;
 652         mm->head_node.start = start + size;
 653         mm->head_node.size = start - mm->head_node.start;
 654         list_add_tail(&mm->head_node.hole_stack, &mm->hole_stack);
 655
 656         mm->color_adjust = NULL;
 657
 658         return 0;
 659 }
 660 EXPORT_SYMBOL(drm_mm_init);
 661
 662 void drm_mm_takedown(struct drm_mm * mm)
 663 {
 664         struct drm_mm_node *entry, *next;
 665
 666         if (!list_empty(&mm->head_node.node_list)) {
 667                 DRM_ERROR("Memory manager not clean. Delaying takedown\n");
 668                 return;
 669         }
 670
 671         spin_lock(&mm->unused_lock);
 672         list_for_each_entry_safe(entry, next, &mm->unused_nodes, node_list) {
 673                 list_del(&entry->node_list);
 674                 kfree(entry);
 675                 --mm->num_unused;
 676         }
 677         spin_unlock(&mm->unused_lock);
 678
 679         BUG_ON(mm->num_unused != 0);
 680 }
 681 EXPORT_SYMBOL(drm_mm_takedown);
 682
 683 void drm_mm_debug_table(struct drm_mm *mm, const char *prefix)
 684 {
 685         struct drm_mm_node *entry;
 686         unsigned long total_used = 0, total_free = 0, total = 0;
 687         unsigned long hole_start, hole_end, hole_size;
 688
 689         hole_start = drm_mm_hole_node_start(&mm->head_node);
 690         hole_end = drm_mm_hole_node_end(&mm->head_node);
 691         hole_size = hole_end - hole_start;
 692         if (hole_size)
 693                 printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: free\n",
 694                         prefix, hole_start, hole_end,
 695                         hole_size);
 696         total_free += hole_size;
 697
 698         drm_mm_for_each_node(entry, mm) {
 699                 printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: used\n",
 700                         prefix, entry->start, entry->start + entry->size,
 701                         entry->size);
 702                 total_used += entry->size;
 703
 704                 if (entry->hole_follows) {
 705                         hole_start = drm_mm_hole_node_start(entry);
 706                         hole_end = drm_mm_hole_node_end(entry);
 707                         hole_size = hole_end - hole_start;
 708                         printk(KERN_DEBUG "%s 0x%08lx-0x%08lx: %8lu: free\n",
 709                                 prefix, hole_start, hole_end,
 710                                 hole_size);
 711                         total_free += hole_size;
 712                 }
 713         }
 714         total = total_free + total_used;
 715
 716         printk(KERN_DEBUG "%s total: %lu, used %lu free %lu\n", prefix, total,
 717                 total_used, total_free);
 718 }
 719 EXPORT_SYMBOL(drm_mm_debug_table);
 720
 721 #if defined(CONFIG_DEBUG_FS)
 722 int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm)
 723 {
 724         struct drm_mm_node *entry;
 725         unsigned long total_used = 0, total_free = 0, total = 0;
 726         unsigned long hole_start, hole_end, hole_size;
 727
 728         hole_start = drm_mm_hole_node_start(&mm->head_node);
 729         hole_end = drm_mm_hole_node_end(&mm->head_node);
 730         hole_size = hole_end - hole_start;
 731         if (hole_size)
 732                 seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: free\n",
 733                                 hole_start, hole_end, hole_size);
 734         total_free += hole_size;
 735
 736         drm_mm_for_each_node(entry, mm) {
 737                 seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: used\n",
 738                                 entry->start, entry->start + entry->size,
 739                                 entry->size);
 740                 total_used += entry->size;
 741                 if (entry->hole_follows) {
 742                         hole_start = drm_mm_hole_node_start(entry);
 743                         hole_end = drm_mm_hole_node_end(entry);
 744                         hole_size = hole_end - hole_start;
 745                         seq_printf(m, "0x%08lx-0x%08lx: 0x%08lx: free\n",
 746                                         hole_start, hole_end, hole_size);
 747                         total_free += hole_size;
 748                 }
 749         }
 750         total = total_free + total_used;
 751
 752         seq_printf(m, "total: %lu, used %lu free %lu\n", total, total_used, total_free);
 753         return 0;
 754 }
 755 EXPORT_SYMBOL(drm_mm_dump_table);
 756 #endif