1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * reservations.c 4 * 5 * Allocation reservations implementation 6 * 7 * Some code borrowed from fs/ext3/balloc.c and is: 8 * 9 * Copyright (C) 1992, 1993, 1994, 1995 10 * Remy Card (card@masi.ibp.fr) 11 * Laboratoire MASI - Institut Blaise Pascal 12 * Universite Pierre et Marie Curie (Paris VI) 13 * 14 * The rest is copyright (C) 2010 Novell. All rights reserved. 15 */ 16 17#include <linux/fs.h> 18#include <linux/types.h> 19#include <linux/highmem.h> 20#include <linux/bitops.h> 21#include <linux/list.h> 22 23#include <cluster/masklog.h> 24 25#include "ocfs2.h" 26#include "ocfs2_trace.h" 27 28#ifdef CONFIG_OCFS2_DEBUG_FS 29#define OCFS2_CHECK_RESERVATIONS 30#endif 31 32static DEFINE_SPINLOCK(resv_lock); 33 34int ocfs2_dir_resv_allowed(struct ocfs2_super *osb) 35{ 36 return (osb->osb_resv_level && osb->osb_dir_resv_level); 37} 38 39static unsigned int ocfs2_resv_window_bits(struct ocfs2_reservation_map *resmap, 40 struct ocfs2_alloc_reservation *resv) 41{ 42 struct ocfs2_super *osb = resmap->m_osb; 43 unsigned int bits; 44 45 if (!(resv->r_flags & OCFS2_RESV_FLAG_DIR)) { 46 /* 8, 16, 32, 64, 128, 256, 512, 1024 */ 47 bits = 4 << osb->osb_resv_level; 48 } else { 49 bits = 4 << osb->osb_dir_resv_level; 50 } 51 return bits; 52} 53 54static inline unsigned int ocfs2_resv_end(struct ocfs2_alloc_reservation *resv) 55{ 56 if (resv->r_len) 57 return resv->r_start + resv->r_len - 1; 58 return resv->r_start; 59} 60 61static inline int ocfs2_resv_empty(struct ocfs2_alloc_reservation *resv) 62{ 63 return !!(resv->r_len == 0); 64} 65 66static inline int ocfs2_resmap_disabled(struct ocfs2_reservation_map *resmap) 67{ 68 if (resmap->m_osb->osb_resv_level == 0) 69 return 1; 70 return 0; 71} 72 73static void ocfs2_dump_resv(struct ocfs2_reservation_map *resmap) 74{ 75 struct ocfs2_super *osb = resmap->m_osb; 76 struct rb_node *node; 77 struct ocfs2_alloc_reservation *resv; 78 int i = 0; 79 80 mlog(ML_NOTICE, "Dumping resmap for device %s. Bitmap length: %u\n", 81 osb->dev_str, resmap->m_bitmap_len); 82 83 node = rb_first(&resmap->m_reservations); 84 while (node) { 85 resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node); 86 87 mlog(ML_NOTICE, "start: %u\tend: %u\tlen: %u\tlast_start: %u" 88 "\tlast_len: %u\n", resv->r_start, 89 ocfs2_resv_end(resv), resv->r_len, resv->r_last_start, 90 resv->r_last_len); 91 92 node = rb_next(node); 93 i++; 94 } 95 96 mlog(ML_NOTICE, "%d reservations found. LRU follows\n", i); 97 98 i = 0; 99 list_for_each_entry(resv, &resmap->m_lru, r_lru) { 100 mlog(ML_NOTICE, "LRU(%d) start: %u\tend: %u\tlen: %u\t" 101 "last_start: %u\tlast_len: %u\n", i, resv->r_start, 102 ocfs2_resv_end(resv), resv->r_len, resv->r_last_start, 103 resv->r_last_len); 104 105 i++; 106 } 107} 108 109#ifdef OCFS2_CHECK_RESERVATIONS 110static int ocfs2_validate_resmap_bits(struct ocfs2_reservation_map *resmap, 111 int i, 112 struct ocfs2_alloc_reservation *resv) 113{ 114 char *disk_bitmap = resmap->m_disk_bitmap; 115 unsigned int start = resv->r_start; 116 unsigned int end = ocfs2_resv_end(resv); 117 118 while (start <= end) { 119 if (ocfs2_test_bit(start, disk_bitmap)) { 120 mlog(ML_ERROR, 121 "reservation %d covers an allocated area " 122 "starting at bit %u!\n", i, start); 123 return 1; 124 } 125 126 start++; 127 } 128 return 0; 129} 130 131static void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap) 132{ 133 unsigned int off = 0; 134 int i = 0; 135 struct rb_node *node; 136 struct ocfs2_alloc_reservation *resv; 137 138 node = rb_first(&resmap->m_reservations); 139 while (node) { 140 resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node); 141 142 if (i > 0 && resv->r_start <= off) { 143 mlog(ML_ERROR, "reservation %d has bad start off!\n", 144 i); 145 goto bad; 146 } 147 148 if (resv->r_len == 0) { 149 mlog(ML_ERROR, "reservation %d has no length!\n", 150 i); 151 goto bad; 152 } 153 154 if (resv->r_start > ocfs2_resv_end(resv)) { 155 mlog(ML_ERROR, "reservation %d has invalid range!\n", 156 i); 157 goto bad; 158 } 159 160 if (ocfs2_resv_end(resv) >= resmap->m_bitmap_len) { 161 mlog(ML_ERROR, "reservation %d extends past bitmap!\n", 162 i); 163 goto bad; 164 } 165 166 if (ocfs2_validate_resmap_bits(resmap, i, resv)) 167 goto bad; 168 169 off = ocfs2_resv_end(resv); 170 node = rb_next(node); 171 172 i++; 173 } 174 return; 175 176bad: 177 ocfs2_dump_resv(resmap); 178 BUG(); 179} 180#else 181static inline void ocfs2_check_resmap(struct ocfs2_reservation_map *resmap) 182{ 183 184} 185#endif 186 187void ocfs2_resv_init_once(struct ocfs2_alloc_reservation *resv) 188{ 189 memset(resv, 0, sizeof(*resv)); 190 INIT_LIST_HEAD(&resv->r_lru); 191} 192 193void ocfs2_resv_set_type(struct ocfs2_alloc_reservation *resv, 194 unsigned int flags) 195{ 196 BUG_ON(flags & ~OCFS2_RESV_TYPES); 197 198 resv->r_flags |= flags; 199} 200 201void ocfs2_resmap_init(struct ocfs2_super *osb, 202 struct ocfs2_reservation_map *resmap) 203{ 204 memset(resmap, 0, sizeof(*resmap)); 205 206 resmap->m_osb = osb; 207 resmap->m_reservations = RB_ROOT; 208 /* m_bitmap_len is initialized to zero by the above memset. */ 209 INIT_LIST_HEAD(&resmap->m_lru); 210} 211 212static void ocfs2_resv_mark_lru(struct ocfs2_reservation_map *resmap, 213 struct ocfs2_alloc_reservation *resv) 214{ 215 assert_spin_locked(&resv_lock); 216 217 if (!list_empty(&resv->r_lru)) 218 list_del_init(&resv->r_lru); 219 220 list_add_tail(&resv->r_lru, &resmap->m_lru); 221} 222 223static void __ocfs2_resv_trunc(struct ocfs2_alloc_reservation *resv) 224{ 225 resv->r_len = 0; 226 resv->r_start = 0; 227} 228 229static void ocfs2_resv_remove(struct ocfs2_reservation_map *resmap, 230 struct ocfs2_alloc_reservation *resv) 231{ 232 if (resv->r_flags & OCFS2_RESV_FLAG_INUSE) { 233 list_del_init(&resv->r_lru); 234 rb_erase(&resv->r_node, &resmap->m_reservations); 235 resv->r_flags &= ~OCFS2_RESV_FLAG_INUSE; 236 } 237} 238 239static void __ocfs2_resv_discard(struct ocfs2_reservation_map *resmap, 240 struct ocfs2_alloc_reservation *resv) 241{ 242 assert_spin_locked(&resv_lock); 243 244 __ocfs2_resv_trunc(resv); 245 /* 246 * last_len and last_start no longer make sense if 247 * we're changing the range of our allocations. 248 */ 249 resv->r_last_len = resv->r_last_start = 0; 250 251 ocfs2_resv_remove(resmap, resv); 252} 253 254/* does nothing if 'resv' is null */ 255void ocfs2_resv_discard(struct ocfs2_reservation_map *resmap, 256 struct ocfs2_alloc_reservation *resv) 257{ 258 if (resv) { 259 spin_lock(&resv_lock); 260 __ocfs2_resv_discard(resmap, resv); 261 spin_unlock(&resv_lock); 262 } 263} 264 265static void ocfs2_resmap_clear_all_resv(struct ocfs2_reservation_map *resmap) 266{ 267 struct rb_node *node; 268 struct ocfs2_alloc_reservation *resv; 269 270 assert_spin_locked(&resv_lock); 271 272 while ((node = rb_last(&resmap->m_reservations)) != NULL) { 273 resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node); 274 275 __ocfs2_resv_discard(resmap, resv); 276 } 277} 278 279void ocfs2_resmap_restart(struct ocfs2_reservation_map *resmap, 280 unsigned int clen, char *disk_bitmap) 281{ 282 if (ocfs2_resmap_disabled(resmap)) 283 return; 284 285 spin_lock(&resv_lock); 286 287 ocfs2_resmap_clear_all_resv(resmap); 288 resmap->m_bitmap_len = clen; 289 resmap->m_disk_bitmap = disk_bitmap; 290 291 spin_unlock(&resv_lock); 292} 293 294void ocfs2_resmap_uninit(struct ocfs2_reservation_map *resmap) 295{ 296 /* Does nothing for now. Keep this around for API symmetry */ 297} 298 299static void ocfs2_resv_insert(struct ocfs2_reservation_map *resmap, 300 struct ocfs2_alloc_reservation *new) 301{ 302 struct rb_root *root = &resmap->m_reservations; 303 struct rb_node *parent = NULL; 304 struct rb_node **p = &root->rb_node; 305 struct ocfs2_alloc_reservation *tmp; 306 307 assert_spin_locked(&resv_lock); 308 309 trace_ocfs2_resv_insert(new->r_start, new->r_len); 310 311 while (*p) { 312 parent = *p; 313 314 tmp = rb_entry(parent, struct ocfs2_alloc_reservation, r_node); 315 316 if (new->r_start < tmp->r_start) { 317 p = &(*p)->rb_left; 318 319 /* 320 * This is a good place to check for 321 * overlapping reservations. 322 */ 323 BUG_ON(ocfs2_resv_end(new) >= tmp->r_start); 324 } else if (new->r_start > ocfs2_resv_end(tmp)) { 325 p = &(*p)->rb_right; 326 } else { 327 /* This should never happen! */ 328 mlog(ML_ERROR, "Duplicate reservation window!\n"); 329 BUG(); 330 } 331 } 332 333 rb_link_node(&new->r_node, parent, p); 334 rb_insert_color(&new->r_node, root); 335 new->r_flags |= OCFS2_RESV_FLAG_INUSE; 336 337 ocfs2_resv_mark_lru(resmap, new); 338 339 ocfs2_check_resmap(resmap); 340} 341 342/** 343 * ocfs2_find_resv_lhs() - find the window which contains goal 344 * @resmap: reservation map to search 345 * @goal: which bit to search for 346 * 347 * If a window containing that goal is not found, we return the window 348 * which comes before goal. Returns NULL on empty rbtree or no window 349 * before goal. 350 */ 351static struct ocfs2_alloc_reservation * 352ocfs2_find_resv_lhs(struct ocfs2_reservation_map *resmap, unsigned int goal) 353{ 354 struct ocfs2_alloc_reservation *resv = NULL; 355 struct ocfs2_alloc_reservation *prev_resv = NULL; 356 struct rb_node *node = resmap->m_reservations.rb_node; 357 358 assert_spin_locked(&resv_lock); 359 360 if (!node) 361 return NULL; 362 363 node = rb_first(&resmap->m_reservations); 364 while (node) { 365 resv = rb_entry(node, struct ocfs2_alloc_reservation, r_node); 366 367 if (resv->r_start <= goal && ocfs2_resv_end(resv) >= goal) 368 break; 369 370 /* Check if we overshot the reservation just before goal? */ 371 if (resv->r_start > goal) { 372 resv = prev_resv; 373 break; 374 } 375 376 prev_resv = resv; 377 node = rb_next(node); 378 } 379 380 return resv; 381} 382 383/* 384 * We are given a range within the bitmap, which corresponds to a gap 385 * inside the reservations tree (search_start, search_len). The range 386 * can be anything from the whole bitmap, to a gap between 387 * reservations. 388 * 389 * The start value of *rstart is insignificant. 390 * 391 * This function searches the bitmap range starting at search_start 392 * with length search_len for a set of contiguous free bits. We try 393 * to find up to 'wanted' bits, but can sometimes return less. 394 * 395 * Returns the length of allocation, 0 if no free bits are found. 396 * 397 * *cstart and *clen will also be populated with the result. 398 */ 399static int ocfs2_resmap_find_free_bits(struct ocfs2_reservation_map *resmap, 400 unsigned int wanted, 401 unsigned int search_start, 402 unsigned int search_len, 403 unsigned int *rstart, 404 unsigned int *rlen) 405{ 406 void *bitmap = resmap->m_disk_bitmap; 407 unsigned int best_start, best_len = 0; 408 int offset, start, found; 409 410 trace_ocfs2_resmap_find_free_bits_begin(search_start, search_len, 411 wanted, resmap->m_bitmap_len); 412 413 found = best_start = best_len = 0; 414 415 start = search_start; 416 while ((offset = ocfs2_find_next_zero_bit(bitmap, resmap->m_bitmap_len, 417 start)) != -1) { 418 /* Search reached end of the region */ 419 if (offset >= (search_start + search_len)) 420 break; 421 422 if (offset == start) { 423 /* we found a zero */ 424 found++; 425 /* move start to the next bit to test */ 426 start++; 427 } else { 428 /* got a zero after some ones */ 429 found = 1; 430 start = offset + 1; 431 } 432 if (found > best_len) { 433 best_len = found; 434 best_start = start - found; 435 } 436 437 if (found >= wanted) 438 break; 439 } 440 441 if (best_len == 0) 442 return 0; 443 444 if (best_len >= wanted) 445 best_len = wanted; 446 447 *rlen = best_len; 448 *rstart = best_start; 449 450 trace_ocfs2_resmap_find_free_bits_end(best_start, best_len); 451 452 return *rlen; 453} 454 455static void __ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap, 456 struct ocfs2_alloc_reservation *resv, 457 unsigned int goal, unsigned int wanted) 458{ 459 struct rb_root *root = &resmap->m_reservations; 460 unsigned int gap_start, gap_end, gap_len; 461 struct ocfs2_alloc_reservation *prev_resv, *next_resv; 462 struct rb_node *prev, *next; 463 unsigned int cstart, clen; 464 unsigned int best_start = 0, best_len = 0; 465 466 /* 467 * Nasty cases to consider: 468 * 469 * - rbtree is empty 470 * - our window should be first in all reservations 471 * - our window should be last in all reservations 472 * - need to make sure we don't go past end of bitmap 473 */ 474 trace_ocfs2_resv_find_window_begin(resv->r_start, ocfs2_resv_end(resv), 475 goal, wanted, RB_EMPTY_ROOT(root)); 476 477 assert_spin_locked(&resv_lock); 478 479 if (RB_EMPTY_ROOT(root)) { 480 /* 481 * Easiest case - empty tree. We can just take 482 * whatever window of free bits we want. 483 */ 484 clen = ocfs2_resmap_find_free_bits(resmap, wanted, goal, 485 resmap->m_bitmap_len - goal, 486 &cstart, &clen); 487 488 /* 489 * This should never happen - the local alloc window 490 * will always have free bits when we're called. 491 */ 492 BUG_ON(goal == 0 && clen == 0); 493 494 if (clen == 0) 495 return; 496 497 resv->r_start = cstart; 498 resv->r_len = clen; 499 500 ocfs2_resv_insert(resmap, resv); 501 return; 502 } 503 504 prev_resv = ocfs2_find_resv_lhs(resmap, goal); 505 506 if (prev_resv == NULL) { 507 /* 508 * A NULL here means that the search code couldn't 509 * find a window that starts before goal. 510 * 511 * However, we can take the first window after goal, 512 * which is also by definition, the leftmost window in 513 * the entire tree. If we can find free bits in the 514 * gap between goal and the LHS window, then the 515 * reservation can safely be placed there. 516 * 517 * Otherwise we fall back to a linear search, checking 518 * the gaps in between windows for a place to 519 * allocate. 520 */ 521 522 next = rb_first(root); 523 next_resv = rb_entry(next, struct ocfs2_alloc_reservation, 524 r_node); 525 526 /* 527 * The search should never return such a window. (see 528 * comment above 529 */ 530 if (next_resv->r_start <= goal) { 531 mlog(ML_ERROR, "goal: %u next_resv: start %u len %u\n", 532 goal, next_resv->r_start, next_resv->r_len); 533 ocfs2_dump_resv(resmap); 534 BUG(); 535 } 536 537 clen = ocfs2_resmap_find_free_bits(resmap, wanted, goal, 538 next_resv->r_start - goal, 539 &cstart, &clen); 540 if (clen) { 541 best_len = clen; 542 best_start = cstart; 543 if (best_len == wanted) 544 goto out_insert; 545 } 546 547 prev_resv = next_resv; 548 next_resv = NULL; 549 } 550 551 trace_ocfs2_resv_find_window_prev(prev_resv->r_start, 552 ocfs2_resv_end(prev_resv)); 553 554 prev = &prev_resv->r_node; 555 556 /* Now we do a linear search for a window, starting at 'prev_rsv' */ 557 while (1) { 558 next = rb_next(prev); 559 if (next) { 560 next_resv = rb_entry(next, 561 struct ocfs2_alloc_reservation, 562 r_node); 563 564 gap_start = ocfs2_resv_end(prev_resv) + 1; 565 gap_end = next_resv->r_start - 1; 566 gap_len = gap_end - gap_start + 1; 567 } else { 568 /* 569 * We're at the rightmost edge of the 570 * tree. See if a reservation between this 571 * window and the end of the bitmap will work. 572 */ 573 gap_start = ocfs2_resv_end(prev_resv) + 1; 574 gap_len = resmap->m_bitmap_len - gap_start; 575 gap_end = resmap->m_bitmap_len - 1; 576 } 577 578 trace_ocfs2_resv_find_window_next(next ? next_resv->r_start: -1, 579 next ? ocfs2_resv_end(next_resv) : -1); 580 /* 581 * No need to check this gap if we have already found 582 * a larger region of free bits. 583 */ 584 if (gap_len <= best_len) 585 goto next_resv; 586 587 clen = ocfs2_resmap_find_free_bits(resmap, wanted, gap_start, 588 gap_len, &cstart, &clen); 589 if (clen == wanted) { 590 best_len = clen; 591 best_start = cstart; 592 goto out_insert; 593 } else if (clen > best_len) { 594 best_len = clen; 595 best_start = cstart; 596 } 597 598next_resv: 599 if (!next) 600 break; 601 602 prev = next; 603 prev_resv = rb_entry(prev, struct ocfs2_alloc_reservation, 604 r_node); 605 } 606 607out_insert: 608 if (best_len) { 609 resv->r_start = best_start; 610 resv->r_len = best_len; 611 ocfs2_resv_insert(resmap, resv); 612 } 613} 614 615static void ocfs2_cannibalize_resv(struct ocfs2_reservation_map *resmap, 616 struct ocfs2_alloc_reservation *resv, 617 unsigned int wanted) 618{ 619 struct ocfs2_alloc_reservation *lru_resv; 620 int tmpwindow = !!(resv->r_flags & OCFS2_RESV_FLAG_TMP); 621 unsigned int min_bits; 622 623 if (!tmpwindow) 624 min_bits = ocfs2_resv_window_bits(resmap, resv) >> 1; 625 else 626 min_bits = wanted; /* We at know the temp window will use all 627 * of these bits */ 628 629 /* 630 * Take the first reservation off the LRU as our 'target'. We 631 * don't try to be smart about it. There might be a case for 632 * searching based on size but I don't have enough data to be 633 * sure. --Mark (3/16/2010) 634 */ 635 lru_resv = list_first_entry(&resmap->m_lru, 636 struct ocfs2_alloc_reservation, r_lru); 637 638 trace_ocfs2_cannibalize_resv_begin(lru_resv->r_start, 639 lru_resv->r_len, 640 ocfs2_resv_end(lru_resv)); 641 642 /* 643 * Cannibalize (some or all) of the target reservation and 644 * feed it to the current window. 645 */ 646 if (lru_resv->r_len <= min_bits) { 647 /* 648 * Discard completely if size is less than or equal to a 649 * reasonable threshold - 50% of window bits for non temporary 650 * windows. 651 */ 652 resv->r_start = lru_resv->r_start; 653 resv->r_len = lru_resv->r_len; 654 655 __ocfs2_resv_discard(resmap, lru_resv); 656 } else { 657 unsigned int shrink; 658 if (tmpwindow) 659 shrink = min_bits; 660 else 661 shrink = lru_resv->r_len / 2; 662 663 lru_resv->r_len -= shrink; 664 665 resv->r_start = ocfs2_resv_end(lru_resv) + 1; 666 resv->r_len = shrink; 667 } 668 669 trace_ocfs2_cannibalize_resv_end(resv->r_start, ocfs2_resv_end(resv), 670 resv->r_len, resv->r_last_start, 671 resv->r_last_len); 672 673 ocfs2_resv_insert(resmap, resv); 674} 675 676static void ocfs2_resv_find_window(struct ocfs2_reservation_map *resmap, 677 struct ocfs2_alloc_reservation *resv, 678 unsigned int wanted) 679{ 680 unsigned int goal = 0; 681 682 BUG_ON(!ocfs2_resv_empty(resv)); 683 684 /* 685 * Begin by trying to get a window as close to the previous 686 * one as possible. Using the most recent allocation as a 687 * start goal makes sense. 688 */ 689 if (resv->r_last_len) { 690 goal = resv->r_last_start + resv->r_last_len; 691 if (goal >= resmap->m_bitmap_len) 692 goal = 0; 693 } 694 695 __ocfs2_resv_find_window(resmap, resv, goal, wanted); 696 697 /* Search from last alloc didn't work, try once more from beginning. */ 698 if (ocfs2_resv_empty(resv) && goal != 0) 699 __ocfs2_resv_find_window(resmap, resv, 0, wanted); 700 701 if (ocfs2_resv_empty(resv)) { 702 /* 703 * Still empty? Pull oldest one off the LRU, remove it from 704 * tree, put this one in it's place. 705 */ 706 ocfs2_cannibalize_resv(resmap, resv, wanted); 707 } 708 709 BUG_ON(ocfs2_resv_empty(resv)); 710} 711 712int ocfs2_resmap_resv_bits(struct ocfs2_reservation_map *resmap, 713 struct ocfs2_alloc_reservation *resv, 714 int *cstart, int *clen) 715{ 716 if (resv == NULL || ocfs2_resmap_disabled(resmap)) 717 return -ENOSPC; 718 719 spin_lock(&resv_lock); 720 721 if (ocfs2_resv_empty(resv)) { 722 /* 723 * We don't want to over-allocate for temporary 724 * windows. Otherwise, we run the risk of fragmenting the 725 * allocation space. 726 */ 727 unsigned int wanted = ocfs2_resv_window_bits(resmap, resv); 728 729 if ((resv->r_flags & OCFS2_RESV_FLAG_TMP) || wanted < *clen) 730 wanted = *clen; 731 732 /* 733 * Try to get a window here. If it works, we must fall 734 * through and test the bitmap . This avoids some 735 * ping-ponging of windows due to non-reserved space 736 * being allocation before we initialize a window for 737 * that inode. 738 */ 739 ocfs2_resv_find_window(resmap, resv, wanted); 740 trace_ocfs2_resmap_resv_bits(resv->r_start, resv->r_len); 741 } 742 743 BUG_ON(ocfs2_resv_empty(resv)); 744 745 *cstart = resv->r_start; 746 *clen = resv->r_len; 747 748 spin_unlock(&resv_lock); 749 return 0; 750} 751 752static void 753 ocfs2_adjust_resv_from_alloc(struct ocfs2_reservation_map *resmap, 754 struct ocfs2_alloc_reservation *resv, 755 unsigned int start, unsigned int end) 756{ 757 unsigned int rhs = 0; 758 unsigned int old_end = ocfs2_resv_end(resv); 759 760 BUG_ON(start != resv->r_start || old_end < end); 761 762 /* 763 * Completely used? We can remove it then. 764 */ 765 if (old_end == end) { 766 __ocfs2_resv_discard(resmap, resv); 767 return; 768 } 769 770 rhs = old_end - end; 771 772 /* 773 * This should have been trapped above. 774 */ 775 BUG_ON(rhs == 0); 776 777 resv->r_start = end + 1; 778 resv->r_len = old_end - resv->r_start + 1; 779} 780 781void ocfs2_resmap_claimed_bits(struct ocfs2_reservation_map *resmap, 782 struct ocfs2_alloc_reservation *resv, 783 u32 cstart, u32 clen) 784{ 785 unsigned int cend = cstart + clen - 1; 786 787 if (resmap == NULL || ocfs2_resmap_disabled(resmap)) 788 return; 789 790 if (resv == NULL) 791 return; 792 793 BUG_ON(cstart != resv->r_start); 794 795 spin_lock(&resv_lock); 796 797 trace_ocfs2_resmap_claimed_bits_begin(cstart, cend, clen, resv->r_start, 798 ocfs2_resv_end(resv), resv->r_len, 799 resv->r_last_start, 800 resv->r_last_len); 801 802 BUG_ON(cstart < resv->r_start); 803 BUG_ON(cstart > ocfs2_resv_end(resv)); 804 BUG_ON(cend > ocfs2_resv_end(resv)); 805 806 ocfs2_adjust_resv_from_alloc(resmap, resv, cstart, cend); 807 resv->r_last_start = cstart; 808 resv->r_last_len = clen; 809 810 /* 811 * May have been discarded above from 812 * ocfs2_adjust_resv_from_alloc(). 813 */ 814 if (!ocfs2_resv_empty(resv)) 815 ocfs2_resv_mark_lru(resmap, resv); 816 817 trace_ocfs2_resmap_claimed_bits_end(resv->r_start, ocfs2_resv_end(resv), 818 resv->r_len, resv->r_last_start, 819 resv->r_last_len); 820 821 ocfs2_check_resmap(resmap); 822 823 spin_unlock(&resv_lock); 824} 825