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/** 51 * DOC: Overview 52 * 53 * drm_mm provides a simple range allocator. The drivers are free to use the 54 * resource allocator from the linux core if it suits them, the upside of drm_mm 55 * is that it's in the DRM core. Which means that it's easier to extend for 56 * some of the crazier special purpose needs of gpus. 57 * 58 * The main data struct is &drm_mm, allocations are tracked in &drm_mm_node. 59 * Drivers are free to embed either of them into their own suitable 60 * datastructures. drm_mm itself will not do any allocations of its own, so if 61 * drivers choose not to embed nodes they need to still allocate them 62 * themselves. 63 * 64 * The range allocator also supports reservation of preallocated blocks. This is 65 * useful for taking over initial mode setting configurations from the firmware, 66 * where an object needs to be created which exactly matches the firmware's 67 * scanout target. As long as the range is still free it can be inserted anytime 68 * after the allocator is initialized, which helps with avoiding looped 69 * depencies in the driver load sequence. 70 * 71 * drm_mm maintains a stack of most recently freed holes, which of all 72 * simplistic datastructures seems to be a fairly decent approach to clustering 73 * allocations and avoiding too much fragmentation. This means free space 74 * searches are O(num_holes). Given that all the fancy features drm_mm supports 75 * something better would be fairly complex and since gfx thrashing is a fairly 76 * steep cliff not a real concern. Removing a node again is O(1). 77 * 78 * drm_mm supports a few features: Alignment and range restrictions can be 79 * supplied. Further more every &drm_mm_node has a color value (which is just an 80 * opaqua unsigned long) which in conjunction with a driver callback can be used 81 * to implement sophisticated placement restrictions. The i915 DRM driver uses 82 * this to implement guard pages between incompatible caching domains in the 83 * graphics TT. 84 * 85 * Two behaviors are supported for searching and allocating: bottom-up and top-down. 86 * The default is bottom-up. Top-down allocation can be used if the memory area 87 * has different restrictions, or just to reduce fragmentation. 88 * 89 * Finally iteration helpers to walk all nodes and all holes are provided as are 90 * some basic allocator dumpers for debugging. 91 */ 92 93static struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm, 94 u64 size, 95 unsigned alignment, 96 unsigned long color, 97 enum drm_mm_search_flags flags); 98static struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm, 99 u64 size, 100 unsigned alignment, 101 unsigned long color, 102 u64 start, 103 u64 end, 104 enum drm_mm_search_flags flags); 105 106static void drm_mm_insert_helper(struct drm_mm_node *hole_node, 107 struct drm_mm_node *node, 108 u64 size, unsigned alignment, 109 unsigned long color, 110 enum drm_mm_allocator_flags flags) 111{ 112 struct drm_mm *mm = hole_node->mm; 113 u64 hole_start = drm_mm_hole_node_start(hole_node); 114 u64 hole_end = drm_mm_hole_node_end(hole_node); 115 u64 adj_start = hole_start; 116 u64 adj_end = hole_end; 117 118 BUG_ON(node->allocated); 119 120 if (mm->color_adjust) 121 mm->color_adjust(hole_node, color, &adj_start, &adj_end); 122 123 if (flags & DRM_MM_CREATE_TOP) 124 adj_start = adj_end - size; 125 126 if (alignment) { 127 u64 tmp = adj_start; 128 unsigned rem; 129 130 rem = do_div(tmp, alignment); 131 if (rem) { 132 if (flags & DRM_MM_CREATE_TOP) 133 adj_start -= rem; 134 else 135 adj_start += alignment - rem; 136 } 137 } 138 139 BUG_ON(adj_start < hole_start); 140 BUG_ON(adj_end > hole_end); 141 142 if (adj_start == hole_start) { 143 hole_node->hole_follows = 0; 144 list_del(&hole_node->hole_stack); 145 } 146 147 node->start = adj_start; 148 node->size = size; 149 node->mm = mm; 150 node->color = color; 151 node->allocated = 1; 152 153 INIT_LIST_HEAD(&node->hole_stack); 154 list_add(&node->node_list, &hole_node->node_list); 155 156 BUG_ON(node->start + node->size > adj_end); 157 158 node->hole_follows = 0; 159 if (__drm_mm_hole_node_start(node) < hole_end) { 160 list_add(&node->hole_stack, &mm->hole_stack); 161 node->hole_follows = 1; 162 } 163} 164 165/** 166 * drm_mm_reserve_node - insert an pre-initialized node 167 * @mm: drm_mm allocator to insert @node into 168 * @node: drm_mm_node to insert 169 * 170 * This functions inserts an already set-up drm_mm_node into the allocator, 171 * meaning that start, size and color must be set by the caller. This is useful 172 * to initialize the allocator with preallocated objects which must be set-up 173 * before the range allocator can be set-up, e.g. when taking over a firmware 174 * framebuffer. 175 * 176 * Returns: 177 * 0 on success, -ENOSPC if there's no hole where @node is. 178 */ 179int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node) 180{ 181 struct drm_mm_node *hole; 182 u64 end = node->start + node->size; 183 u64 hole_start; 184 u64 hole_end; 185 186 BUG_ON(node == NULL); 187 188 /* Find the relevant hole to add our node to */ 189 drm_mm_for_each_hole(hole, mm, hole_start, hole_end) { 190 if (hole_start > node->start || hole_end < end) 191 continue; 192 193 node->mm = mm; 194 node->allocated = 1; 195 196 INIT_LIST_HEAD(&node->hole_stack); 197 list_add(&node->node_list, &hole->node_list); 198 199 if (node->start == hole_start) { 200 hole->hole_follows = 0; 201 list_del_init(&hole->hole_stack); 202 } 203 204 node->hole_follows = 0; 205 if (end != hole_end) { 206 list_add(&node->hole_stack, &mm->hole_stack); 207 node->hole_follows = 1; 208 } 209 210 return 0; 211 } 212 213 return -ENOSPC; 214} 215EXPORT_SYMBOL(drm_mm_reserve_node); 216 217/** 218 * drm_mm_insert_node_generic - search for space and insert @node 219 * @mm: drm_mm to allocate from 220 * @node: preallocate node to insert 221 * @size: size of the allocation 222 * @alignment: alignment of the allocation 223 * @color: opaque tag value to use for this node 224 * @sflags: flags to fine-tune the allocation search 225 * @aflags: flags to fine-tune the allocation behavior 226 * 227 * The preallocated node must be cleared to 0. 228 * 229 * Returns: 230 * 0 on success, -ENOSPC if there's no suitable hole. 231 */ 232int drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node, 233 u64 size, unsigned alignment, 234 unsigned long color, 235 enum drm_mm_search_flags sflags, 236 enum drm_mm_allocator_flags aflags) 237{ 238 struct drm_mm_node *hole_node; 239 240 hole_node = drm_mm_search_free_generic(mm, size, alignment, 241 color, sflags); 242 if (!hole_node) 243 return -ENOSPC; 244 245 drm_mm_insert_helper(hole_node, node, size, alignment, color, aflags); 246 return 0; 247} 248EXPORT_SYMBOL(drm_mm_insert_node_generic); 249 250static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node, 251 struct drm_mm_node *node, 252 u64 size, unsigned alignment, 253 unsigned long color, 254 u64 start, u64 end, 255 enum drm_mm_allocator_flags flags) 256{ 257 struct drm_mm *mm = hole_node->mm; 258 u64 hole_start = drm_mm_hole_node_start(hole_node); 259 u64 hole_end = drm_mm_hole_node_end(hole_node); 260 u64 adj_start = hole_start; 261 u64 adj_end = hole_end; 262 263 BUG_ON(!hole_node->hole_follows || node->allocated); 264 265 if (adj_start < start) 266 adj_start = start; 267 if (adj_end > end) 268 adj_end = end; 269 270 if (flags & DRM_MM_CREATE_TOP) 271 adj_start = adj_end - size; 272 273 if (mm->color_adjust) 274 mm->color_adjust(hole_node, color, &adj_start, &adj_end); 275 276 if (alignment) { 277 u64 tmp = adj_start; 278 unsigned rem; 279 280 rem = do_div(tmp, alignment); 281 if (rem) { 282 if (flags & DRM_MM_CREATE_TOP) 283 adj_start -= rem; 284 else 285 adj_start += alignment - rem; 286 } 287 } 288 289 if (adj_start == hole_start) { 290 hole_node->hole_follows = 0; 291 list_del(&hole_node->hole_stack); 292 } 293 294 node->start = adj_start; 295 node->size = size; 296 node->mm = mm; 297 node->color = color; 298 node->allocated = 1; 299 300 INIT_LIST_HEAD(&node->hole_stack); 301 list_add(&node->node_list, &hole_node->node_list); 302 303 BUG_ON(node->start < start); 304 BUG_ON(node->start < adj_start); 305 BUG_ON(node->start + node->size > adj_end); 306 BUG_ON(node->start + node->size > end); 307 308 node->hole_follows = 0; 309 if (__drm_mm_hole_node_start(node) < hole_end) { 310 list_add(&node->hole_stack, &mm->hole_stack); 311 node->hole_follows = 1; 312 } 313} 314 315/** 316 * drm_mm_insert_node_in_range_generic - ranged search for space and insert @node 317 * @mm: drm_mm to allocate from 318 * @node: preallocate node to insert 319 * @size: size of the allocation 320 * @alignment: alignment of the allocation 321 * @color: opaque tag value to use for this node 322 * @start: start of the allowed range for this node 323 * @end: end of the allowed range for this node 324 * @sflags: flags to fine-tune the allocation search 325 * @aflags: flags to fine-tune the allocation behavior 326 * 327 * The preallocated node must be cleared to 0. 328 * 329 * Returns: 330 * 0 on success, -ENOSPC if there's no suitable hole. 331 */ 332int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, struct drm_mm_node *node, 333 u64 size, unsigned alignment, 334 unsigned long color, 335 u64 start, u64 end, 336 enum drm_mm_search_flags sflags, 337 enum drm_mm_allocator_flags aflags) 338{ 339 struct drm_mm_node *hole_node; 340 341 hole_node = drm_mm_search_free_in_range_generic(mm, 342 size, alignment, color, 343 start, end, sflags); 344 if (!hole_node) 345 return -ENOSPC; 346 347 drm_mm_insert_helper_range(hole_node, node, 348 size, alignment, color, 349 start, end, aflags); 350 return 0; 351} 352EXPORT_SYMBOL(drm_mm_insert_node_in_range_generic); 353 354/** 355 * drm_mm_remove_node - Remove a memory node from the allocator. 356 * @node: drm_mm_node to remove 357 * 358 * This just removes a node from its drm_mm allocator. The node does not need to 359 * be cleared again before it can be re-inserted into this or any other drm_mm 360 * allocator. It is a bug to call this function on a un-allocated node. 361 */ 362void drm_mm_remove_node(struct drm_mm_node *node) 363{ 364 struct drm_mm *mm = node->mm; 365 struct drm_mm_node *prev_node; 366 367 if (WARN_ON(!node->allocated)) 368 return; 369 370 BUG_ON(node->scanned_block || node->scanned_prev_free 371 || node->scanned_next_free); 372 373 prev_node = 374 list_entry(node->node_list.prev, struct drm_mm_node, node_list); 375 376 if (node->hole_follows) { 377 BUG_ON(__drm_mm_hole_node_start(node) == 378 __drm_mm_hole_node_end(node)); 379 list_del(&node->hole_stack); 380 } else 381 BUG_ON(__drm_mm_hole_node_start(node) != 382 __drm_mm_hole_node_end(node)); 383 384 385 if (!prev_node->hole_follows) { 386 prev_node->hole_follows = 1; 387 list_add(&prev_node->hole_stack, &mm->hole_stack); 388 } else 389 list_move(&prev_node->hole_stack, &mm->hole_stack); 390 391 list_del(&node->node_list); 392 node->allocated = 0; 393} 394EXPORT_SYMBOL(drm_mm_remove_node); 395 396static int check_free_hole(u64 start, u64 end, u64 size, unsigned alignment) 397{ 398 if (end - start < size) 399 return 0; 400 401 if (alignment) { 402 u64 tmp = start; 403 unsigned rem; 404 405 rem = do_div(tmp, alignment); 406 if (rem) 407 start += alignment - rem; 408 } 409 410 return end >= start + size; 411} 412 413static struct drm_mm_node *drm_mm_search_free_generic(const struct drm_mm *mm, 414 u64 size, 415 unsigned alignment, 416 unsigned long color, 417 enum drm_mm_search_flags flags) 418{ 419 struct drm_mm_node *entry; 420 struct drm_mm_node *best; 421 u64 adj_start; 422 u64 adj_end; 423 u64 best_size; 424 425 BUG_ON(mm->scanned_blocks); 426 427 best = NULL; 428 best_size = ~0UL; 429 430 __drm_mm_for_each_hole(entry, mm, adj_start, adj_end, 431 flags & DRM_MM_SEARCH_BELOW) { 432 u64 hole_size = adj_end - adj_start; 433 434 if (mm->color_adjust) { 435 mm->color_adjust(entry, color, &adj_start, &adj_end); 436 if (adj_end <= adj_start) 437 continue; 438 } 439 440 if (!check_free_hole(adj_start, adj_end, size, alignment)) 441 continue; 442 443 if (!(flags & DRM_MM_SEARCH_BEST)) 444 return entry; 445 446 if (hole_size < best_size) { 447 best = entry; 448 best_size = hole_size; 449 } 450 } 451 452 return best; 453} 454 455static struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_mm *mm, 456 u64 size, 457 unsigned alignment, 458 unsigned long color, 459 u64 start, 460 u64 end, 461 enum drm_mm_search_flags flags) 462{ 463 struct drm_mm_node *entry; 464 struct drm_mm_node *best; 465 u64 adj_start; 466 u64 adj_end; 467 u64 best_size; 468 469 BUG_ON(mm->scanned_blocks); 470 471 best = NULL; 472 best_size = ~0UL; 473 474 __drm_mm_for_each_hole(entry, mm, adj_start, adj_end, 475 flags & DRM_MM_SEARCH_BELOW) { 476 u64 hole_size = adj_end - adj_start; 477 478 if (adj_start < start) 479 adj_start = start; 480 if (adj_end > end) 481 adj_end = end; 482 483 if (mm->color_adjust) { 484 mm->color_adjust(entry, color, &adj_start, &adj_end); 485 if (adj_end <= adj_start) 486 continue; 487 } 488 489 if (!check_free_hole(adj_start, adj_end, size, alignment)) 490 continue; 491 492 if (!(flags & DRM_MM_SEARCH_BEST)) 493 return entry; 494 495 if (hole_size < best_size) { 496 best = entry; 497 best_size = hole_size; 498 } 499 } 500 501 return best; 502} 503 504/** 505 * drm_mm_replace_node - move an allocation from @old to @new 506 * @old: drm_mm_node to remove from the allocator 507 * @new: drm_mm_node which should inherit @old's allocation 508 * 509 * This is useful for when drivers embed the drm_mm_node structure and hence 510 * can't move allocations by reassigning pointers. It's a combination of remove 511 * and insert with the guarantee that the allocation start will match. 512 */ 513void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new) 514{ 515 list_replace(&old->node_list, &new->node_list); 516 list_replace(&old->hole_stack, &new->hole_stack); 517 new->hole_follows = old->hole_follows; 518 new->mm = old->mm; 519 new->start = old->start; 520 new->size = old->size; 521 new->color = old->color; 522 523 old->allocated = 0; 524 new->allocated = 1; 525} 526EXPORT_SYMBOL(drm_mm_replace_node); 527 528/** 529 * DOC: lru scan roaster 530 * 531 * Very often GPUs need to have continuous allocations for a given object. When 532 * evicting objects to make space for a new one it is therefore not most 533 * efficient when we simply start to select all objects from the tail of an LRU 534 * until there's a suitable hole: Especially for big objects or nodes that 535 * otherwise have special allocation constraints there's a good chance we evict 536 * lots of (smaller) objects unecessarily. 537 * 538 * The DRM range allocator supports this use-case through the scanning 539 * interfaces. First a scan operation needs to be initialized with 540 * drm_mm_init_scan() or drm_mm_init_scan_with_range(). The the driver adds 541 * objects to the roaster (probably by walking an LRU list, but this can be 542 * freely implemented) until a suitable hole is found or there's no further 543 * evitable object. 544 * 545 * The the driver must walk through all objects again in exactly the reverse 546 * order to restore the allocator state. Note that while the allocator is used 547 * in the scan mode no other operation is allowed. 548 * 549 * Finally the driver evicts all objects selected in the scan. Adding and 550 * removing an object is O(1), and since freeing a node is also O(1) the overall 551 * complexity is O(scanned_objects). So like the free stack which needs to be 552 * walked before a scan operation even begins this is linear in the number of 553 * objects. It doesn't seem to hurt badly. 554 */ 555 556/** 557 * drm_mm_init_scan - initialize lru scanning 558 * @mm: drm_mm to scan 559 * @size: size of the allocation 560 * @alignment: alignment of the allocation 561 * @color: opaque tag value to use for the allocation 562 * 563 * This simply sets up the scanning routines with the parameters for the desired 564 * hole. Note that there's no need to specify allocation flags, since they only 565 * change the place a node is allocated from within a suitable hole. 566 * 567 * Warning: 568 * As long as the scan list is non-empty, no other operations than 569 * adding/removing nodes to/from the scan list are allowed. 570 */ 571void drm_mm_init_scan(struct drm_mm *mm, 572 u64 size, 573 unsigned alignment, 574 unsigned long color) 575{ 576 mm->scan_color = color; 577 mm->scan_alignment = alignment; 578 mm->scan_size = size; 579 mm->scanned_blocks = 0; 580 mm->scan_hit_start = 0; 581 mm->scan_hit_end = 0; 582 mm->scan_check_range = 0; 583 mm->prev_scanned_node = NULL; 584} 585EXPORT_SYMBOL(drm_mm_init_scan); 586 587/** 588 * drm_mm_init_scan - initialize range-restricted lru scanning 589 * @mm: drm_mm to scan 590 * @size: size of the allocation 591 * @alignment: alignment of the allocation 592 * @color: opaque tag value to use for the allocation 593 * @start: start of the allowed range for the allocation 594 * @end: end of the allowed range for the allocation 595 * 596 * This simply sets up the scanning routines with the parameters for the desired 597 * hole. Note that there's no need to specify allocation flags, since they only 598 * change the place a node is allocated from within a suitable hole. 599 * 600 * Warning: 601 * As long as the scan list is non-empty, no other operations than 602 * adding/removing nodes to/from the scan list are allowed. 603 */ 604void drm_mm_init_scan_with_range(struct drm_mm *mm, 605 u64 size, 606 unsigned alignment, 607 unsigned long color, 608 u64 start, 609 u64 end) 610{ 611 mm->scan_color = color; 612 mm->scan_alignment = alignment; 613 mm->scan_size = size; 614 mm->scanned_blocks = 0; 615 mm->scan_hit_start = 0; 616 mm->scan_hit_end = 0; 617 mm->scan_start = start; 618 mm->scan_end = end; 619 mm->scan_check_range = 1; 620 mm->prev_scanned_node = NULL; 621} 622EXPORT_SYMBOL(drm_mm_init_scan_with_range); 623 624/** 625 * drm_mm_scan_add_block - add a node to the scan list 626 * @node: drm_mm_node to add 627 * 628 * Add a node to the scan list that might be freed to make space for the desired 629 * hole. 630 * 631 * Returns: 632 * True if a hole has been found, false otherwise. 633 */ 634bool drm_mm_scan_add_block(struct drm_mm_node *node) 635{ 636 struct drm_mm *mm = node->mm; 637 struct drm_mm_node *prev_node; 638 u64 hole_start, hole_end; 639 u64 adj_start, adj_end; 640 641 mm->scanned_blocks++; 642 643 BUG_ON(node->scanned_block); 644 node->scanned_block = 1; 645 646 prev_node = list_entry(node->node_list.prev, struct drm_mm_node, 647 node_list); 648 649 node->scanned_preceeds_hole = prev_node->hole_follows; 650 prev_node->hole_follows = 1; 651 list_del(&node->node_list); 652 node->node_list.prev = &prev_node->node_list; 653 node->node_list.next = &mm->prev_scanned_node->node_list; 654 mm->prev_scanned_node = node; 655 656 adj_start = hole_start = drm_mm_hole_node_start(prev_node); 657 adj_end = hole_end = drm_mm_hole_node_end(prev_node); 658 659 if (mm->scan_check_range) { 660 if (adj_start < mm->scan_start) 661 adj_start = mm->scan_start; 662 if (adj_end > mm->scan_end) 663 adj_end = mm->scan_end; 664 } 665 666 if (mm->color_adjust) 667 mm->color_adjust(prev_node, mm->scan_color, 668 &adj_start, &adj_end); 669 670 if (check_free_hole(adj_start, adj_end, 671 mm->scan_size, mm->scan_alignment)) { 672 mm->scan_hit_start = hole_start; 673 mm->scan_hit_end = hole_end; 674 return true; 675 } 676 677 return false; 678} 679EXPORT_SYMBOL(drm_mm_scan_add_block); 680 681/** 682 * drm_mm_scan_remove_block - remove a node from the scan list 683 * @node: drm_mm_node to remove 684 * 685 * Nodes _must_ be removed in the exact same order from the scan list as they 686 * have been added, otherwise the internal state of the memory manager will be 687 * corrupted. 688 * 689 * When the scan list is empty, the selected memory nodes can be freed. An 690 * immediately following drm_mm_search_free with !DRM_MM_SEARCH_BEST will then 691 * return the just freed block (because its at the top of the free_stack list). 692 * 693 * Returns: 694 * True if this block should be evicted, false otherwise. Will always 695 * return false when no hole has been found. 696 */ 697bool drm_mm_scan_remove_block(struct drm_mm_node *node) 698{ 699 struct drm_mm *mm = node->mm; 700 struct drm_mm_node *prev_node; 701 702 mm->scanned_blocks--; 703 704 BUG_ON(!node->scanned_block); 705 node->scanned_block = 0; 706 707 prev_node = list_entry(node->node_list.prev, struct drm_mm_node, 708 node_list); 709 710 prev_node->hole_follows = node->scanned_preceeds_hole; 711 list_add(&node->node_list, &prev_node->node_list); 712 713 return (drm_mm_hole_node_end(node) > mm->scan_hit_start && 714 node->start < mm->scan_hit_end); 715} 716EXPORT_SYMBOL(drm_mm_scan_remove_block); 717 718/** 719 * drm_mm_clean - checks whether an allocator is clean 720 * @mm: drm_mm allocator to check 721 * 722 * Returns: 723 * True if the allocator is completely free, false if there's still a node 724 * allocated in it. 725 */ 726bool drm_mm_clean(struct drm_mm * mm) 727{ 728 struct list_head *head = &mm->head_node.node_list; 729 730 return (head->next->next == head); 731} 732EXPORT_SYMBOL(drm_mm_clean); 733 734/** 735 * drm_mm_init - initialize a drm-mm allocator 736 * @mm: the drm_mm structure to initialize 737 * @start: start of the range managed by @mm 738 * @size: end of the range managed by @mm 739 * 740 * Note that @mm must be cleared to 0 before calling this function. 741 */ 742void drm_mm_init(struct drm_mm * mm, u64 start, u64 size) 743{ 744 INIT_LIST_HEAD(&mm->hole_stack); 745 mm->scanned_blocks = 0; 746 747 /* Clever trick to avoid a special case in the free hole tracking. */ 748 INIT_LIST_HEAD(&mm->head_node.node_list); 749 INIT_LIST_HEAD(&mm->head_node.hole_stack); 750 mm->head_node.hole_follows = 1; 751 mm->head_node.scanned_block = 0; 752 mm->head_node.scanned_prev_free = 0; 753 mm->head_node.scanned_next_free = 0; 754 mm->head_node.mm = mm; 755 mm->head_node.start = start + size; 756 mm->head_node.size = start - mm->head_node.start; 757 list_add_tail(&mm->head_node.hole_stack, &mm->hole_stack); 758 759 mm->color_adjust = NULL; 760} 761EXPORT_SYMBOL(drm_mm_init); 762 763/** 764 * drm_mm_takedown - clean up a drm_mm allocator 765 * @mm: drm_mm allocator to clean up 766 * 767 * Note that it is a bug to call this function on an allocator which is not 768 * clean. 769 */ 770void drm_mm_takedown(struct drm_mm * mm) 771{ 772 WARN(!list_empty(&mm->head_node.node_list), 773 "Memory manager not clean during takedown.\n"); 774} 775EXPORT_SYMBOL(drm_mm_takedown); 776 777static u64 drm_mm_debug_hole(struct drm_mm_node *entry, 778 const char *prefix) 779{ 780 u64 hole_start, hole_end, hole_size; 781 782 if (entry->hole_follows) { 783 hole_start = drm_mm_hole_node_start(entry); 784 hole_end = drm_mm_hole_node_end(entry); 785 hole_size = hole_end - hole_start; 786 pr_debug("%s %#llx-%#llx: %llu: free\n", prefix, hole_start, 787 hole_end, hole_size); 788 return hole_size; 789 } 790 791 return 0; 792} 793 794/** 795 * drm_mm_debug_table - dump allocator state to dmesg 796 * @mm: drm_mm allocator to dump 797 * @prefix: prefix to use for dumping to dmesg 798 */ 799void drm_mm_debug_table(struct drm_mm *mm, const char *prefix) 800{ 801 struct drm_mm_node *entry; 802 u64 total_used = 0, total_free = 0, total = 0; 803 804 total_free += drm_mm_debug_hole(&mm->head_node, prefix); 805 806 drm_mm_for_each_node(entry, mm) { 807 pr_debug("%s %#llx-%#llx: %llu: used\n", prefix, entry->start, 808 entry->start + entry->size, entry->size); 809 total_used += entry->size; 810 total_free += drm_mm_debug_hole(entry, prefix); 811 } 812 total = total_free + total_used; 813 814 pr_debug("%s total: %llu, used %llu free %llu\n", prefix, total, 815 total_used, total_free); 816} 817EXPORT_SYMBOL(drm_mm_debug_table); 818 819#if defined(CONFIG_DEBUG_FS) 820static u64 drm_mm_dump_hole(struct seq_file *m, struct drm_mm_node *entry) 821{ 822 u64 hole_start, hole_end, hole_size; 823 824 if (entry->hole_follows) { 825 hole_start = drm_mm_hole_node_start(entry); 826 hole_end = drm_mm_hole_node_end(entry); 827 hole_size = hole_end - hole_start; 828 seq_printf(m, "%#llx-%#llx: %llu: free\n", hole_start, 829 hole_end, hole_size); 830 return hole_size; 831 } 832 833 return 0; 834} 835 836/** 837 * drm_mm_dump_table - dump allocator state to a seq_file 838 * @m: seq_file to dump to 839 * @mm: drm_mm allocator to dump 840 */ 841int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm) 842{ 843 struct drm_mm_node *entry; 844 u64 total_used = 0, total_free = 0, total = 0; 845 846 total_free += drm_mm_dump_hole(m, &mm->head_node); 847 848 drm_mm_for_each_node(entry, mm) { 849 seq_printf(m, "%#016llx-%#016llx: %llu: used\n", entry->start, 850 entry->start + entry->size, entry->size); 851 total_used += entry->size; 852 total_free += drm_mm_dump_hole(m, entry); 853 } 854 total = total_free + total_used; 855 856 seq_printf(m, "total: %llu, used %llu free %llu\n", total, 857 total_used, total_free); 858 return 0; 859} 860EXPORT_SYMBOL(drm_mm_dump_table); 861#endif 862