1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (c) 2014 Red Hat, Inc. 4 * All Rights Reserved. 5 */ 6 #include "xfs.h" 7 #include "xfs_fs.h" 8 #include "xfs_shared.h" 9 #include "xfs_format.h" 10 #include "xfs_log_format.h" 11 #include "xfs_trans_resv.h" 12 #include "xfs_sb.h" 13 #include "xfs_mount.h" 14 #include "xfs_trans.h" 15 #include "xfs_alloc.h" 16 #include "xfs_btree.h" 17 #include "xfs_btree_staging.h" 18 #include "xfs_rmap.h" 19 #include "xfs_rmap_btree.h" 20 #include "xfs_trace.h" 21 #include "xfs_error.h" 22 #include "xfs_extent_busy.h" 23 #include "xfs_ag_resv.h" 24 25 /* 26 * Reverse map btree. 27 * 28 * This is a per-ag tree used to track the owner(s) of a given extent. With 29 * reflink it is possible for there to be multiple owners, which is a departure 30 * from classic XFS. Owner records for data extents are inserted when the 31 * extent is mapped and removed when an extent is unmapped. Owner records for 32 * all other block types (i.e. metadata) are inserted when an extent is 33 * allocated and removed when an extent is freed. There can only be one owner 34 * of a metadata extent, usually an inode or some other metadata structure like 35 * an AG btree. 36 * 37 * The rmap btree is part of the free space management, so blocks for the tree 38 * are sourced from the agfl. Hence we need transaction reservation support for 39 * this tree so that the freelist is always large enough. This also impacts on 40 * the minimum space we need to leave free in the AG. 41 * 42 * The tree is ordered by [ag block, owner, offset]. This is a large key size, 43 * but it is the only way to enforce unique keys when a block can be owned by 44 * multiple files at any offset. There's no need to order/search by extent 45 * size for online updating/management of the tree. It is intended that most 46 * reverse lookups will be to find the owner(s) of a particular block, or to 47 * try to recover tree and file data from corrupt primary metadata. 48 */ 49 50 static struct xfs_btree_cur * 51 xfs_rmapbt_dup_cursor( 52 struct xfs_btree_cur *cur) 53 { 54 return xfs_rmapbt_init_cursor(cur->bc_mp, cur->bc_tp, 55 cur->bc_ag.agbp, cur->bc_ag.agno); 56 } 57 58 STATIC void 59 xfs_rmapbt_set_root( 60 struct xfs_btree_cur *cur, 61 union xfs_btree_ptr *ptr, 62 int inc) 63 { 64 struct xfs_buf *agbp = cur->bc_ag.agbp; 65 struct xfs_agf *agf = agbp->b_addr; 66 xfs_agnumber_t seqno = be32_to_cpu(agf->agf_seqno); 67 int btnum = cur->bc_btnum; 68 struct xfs_perag *pag = xfs_perag_get(cur->bc_mp, seqno); 69 70 ASSERT(ptr->s != 0); 71 72 agf->agf_roots[btnum] = ptr->s; 73 be32_add_cpu(&agf->agf_levels[btnum], inc); 74 pag->pagf_levels[btnum] += inc; 75 xfs_perag_put(pag); 76 77 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS); 78 } 79 80 STATIC int 81 xfs_rmapbt_alloc_block( 82 struct xfs_btree_cur *cur, 83 union xfs_btree_ptr *start, 84 union xfs_btree_ptr *new, 85 int *stat) 86 { 87 struct xfs_buf *agbp = cur->bc_ag.agbp; 88 struct xfs_agf *agf = agbp->b_addr; 89 int error; 90 xfs_agblock_t bno; 91 92 /* Allocate the new block from the freelist. If we can't, give up. */ 93 error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_ag.agbp, 94 &bno, 1); 95 if (error) 96 return error; 97 98 trace_xfs_rmapbt_alloc_block(cur->bc_mp, cur->bc_ag.agno, 99 bno, 1); 100 if (bno == NULLAGBLOCK) { 101 *stat = 0; 102 return 0; 103 } 104 105 xfs_extent_busy_reuse(cur->bc_mp, cur->bc_ag.agno, bno, 1, 106 false); 107 108 xfs_trans_agbtree_delta(cur->bc_tp, 1); 109 new->s = cpu_to_be32(bno); 110 be32_add_cpu(&agf->agf_rmap_blocks, 1); 111 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS); 112 113 xfs_ag_resv_rmapbt_alloc(cur->bc_mp, cur->bc_ag.agno); 114 115 *stat = 1; 116 return 0; 117 } 118 119 STATIC int 120 xfs_rmapbt_free_block( 121 struct xfs_btree_cur *cur, 122 struct xfs_buf *bp) 123 { 124 struct xfs_buf *agbp = cur->bc_ag.agbp; 125 struct xfs_agf *agf = agbp->b_addr; 126 xfs_agblock_t bno; 127 int error; 128 129 bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp)); 130 trace_xfs_rmapbt_free_block(cur->bc_mp, cur->bc_ag.agno, 131 bno, 1); 132 be32_add_cpu(&agf->agf_rmap_blocks, -1); 133 xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_RMAP_BLOCKS); 134 error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1); 135 if (error) 136 return error; 137 138 xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1, 139 XFS_EXTENT_BUSY_SKIP_DISCARD); 140 xfs_trans_agbtree_delta(cur->bc_tp, -1); 141 142 xfs_ag_resv_rmapbt_free(cur->bc_mp, cur->bc_ag.agno); 143 144 return 0; 145 } 146 147 STATIC int 148 xfs_rmapbt_get_minrecs( 149 struct xfs_btree_cur *cur, 150 int level) 151 { 152 return cur->bc_mp->m_rmap_mnr[level != 0]; 153 } 154 155 STATIC int 156 xfs_rmapbt_get_maxrecs( 157 struct xfs_btree_cur *cur, 158 int level) 159 { 160 return cur->bc_mp->m_rmap_mxr[level != 0]; 161 } 162 163 STATIC void 164 xfs_rmapbt_init_key_from_rec( 165 union xfs_btree_key *key, 166 union xfs_btree_rec *rec) 167 { 168 key->rmap.rm_startblock = rec->rmap.rm_startblock; 169 key->rmap.rm_owner = rec->rmap.rm_owner; 170 key->rmap.rm_offset = rec->rmap.rm_offset; 171 } 172 173 /* 174 * The high key for a reverse mapping record can be computed by shifting 175 * the startblock and offset to the highest value that would still map 176 * to that record. In practice this means that we add blockcount-1 to 177 * the startblock for all records, and if the record is for a data/attr 178 * fork mapping, we add blockcount-1 to the offset too. 179 */ 180 STATIC void 181 xfs_rmapbt_init_high_key_from_rec( 182 union xfs_btree_key *key, 183 union xfs_btree_rec *rec) 184 { 185 uint64_t off; 186 int adj; 187 188 adj = be32_to_cpu(rec->rmap.rm_blockcount) - 1; 189 190 key->rmap.rm_startblock = rec->rmap.rm_startblock; 191 be32_add_cpu(&key->rmap.rm_startblock, adj); 192 key->rmap.rm_owner = rec->rmap.rm_owner; 193 key->rmap.rm_offset = rec->rmap.rm_offset; 194 if (XFS_RMAP_NON_INODE_OWNER(be64_to_cpu(rec->rmap.rm_owner)) || 195 XFS_RMAP_IS_BMBT_BLOCK(be64_to_cpu(rec->rmap.rm_offset))) 196 return; 197 off = be64_to_cpu(key->rmap.rm_offset); 198 off = (XFS_RMAP_OFF(off) + adj) | (off & ~XFS_RMAP_OFF_MASK); 199 key->rmap.rm_offset = cpu_to_be64(off); 200 } 201 202 STATIC void 203 xfs_rmapbt_init_rec_from_cur( 204 struct xfs_btree_cur *cur, 205 union xfs_btree_rec *rec) 206 { 207 rec->rmap.rm_startblock = cpu_to_be32(cur->bc_rec.r.rm_startblock); 208 rec->rmap.rm_blockcount = cpu_to_be32(cur->bc_rec.r.rm_blockcount); 209 rec->rmap.rm_owner = cpu_to_be64(cur->bc_rec.r.rm_owner); 210 rec->rmap.rm_offset = cpu_to_be64( 211 xfs_rmap_irec_offset_pack(&cur->bc_rec.r)); 212 } 213 214 STATIC void 215 xfs_rmapbt_init_ptr_from_cur( 216 struct xfs_btree_cur *cur, 217 union xfs_btree_ptr *ptr) 218 { 219 struct xfs_agf *agf = cur->bc_ag.agbp->b_addr; 220 221 ASSERT(cur->bc_ag.agno == be32_to_cpu(agf->agf_seqno)); 222 223 ptr->s = agf->agf_roots[cur->bc_btnum]; 224 } 225 226 STATIC int64_t 227 xfs_rmapbt_key_diff( 228 struct xfs_btree_cur *cur, 229 union xfs_btree_key *key) 230 { 231 struct xfs_rmap_irec *rec = &cur->bc_rec.r; 232 struct xfs_rmap_key *kp = &key->rmap; 233 __u64 x, y; 234 int64_t d; 235 236 d = (int64_t)be32_to_cpu(kp->rm_startblock) - rec->rm_startblock; 237 if (d) 238 return d; 239 240 x = be64_to_cpu(kp->rm_owner); 241 y = rec->rm_owner; 242 if (x > y) 243 return 1; 244 else if (y > x) 245 return -1; 246 247 x = XFS_RMAP_OFF(be64_to_cpu(kp->rm_offset)); 248 y = rec->rm_offset; 249 if (x > y) 250 return 1; 251 else if (y > x) 252 return -1; 253 return 0; 254 } 255 256 STATIC int64_t 257 xfs_rmapbt_diff_two_keys( 258 struct xfs_btree_cur *cur, 259 union xfs_btree_key *k1, 260 union xfs_btree_key *k2) 261 { 262 struct xfs_rmap_key *kp1 = &k1->rmap; 263 struct xfs_rmap_key *kp2 = &k2->rmap; 264 int64_t d; 265 __u64 x, y; 266 267 d = (int64_t)be32_to_cpu(kp1->rm_startblock) - 268 be32_to_cpu(kp2->rm_startblock); 269 if (d) 270 return d; 271 272 x = be64_to_cpu(kp1->rm_owner); 273 y = be64_to_cpu(kp2->rm_owner); 274 if (x > y) 275 return 1; 276 else if (y > x) 277 return -1; 278 279 x = XFS_RMAP_OFF(be64_to_cpu(kp1->rm_offset)); 280 y = XFS_RMAP_OFF(be64_to_cpu(kp2->rm_offset)); 281 if (x > y) 282 return 1; 283 else if (y > x) 284 return -1; 285 return 0; 286 } 287 288 static xfs_failaddr_t 289 xfs_rmapbt_verify( 290 struct xfs_buf *bp) 291 { 292 struct xfs_mount *mp = bp->b_mount; 293 struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp); 294 struct xfs_perag *pag = bp->b_pag; 295 xfs_failaddr_t fa; 296 unsigned int level; 297 298 /* 299 * magic number and level verification 300 * 301 * During growfs operations, we can't verify the exact level or owner as 302 * the perag is not fully initialised and hence not attached to the 303 * buffer. In this case, check against the maximum tree depth. 304 * 305 * Similarly, during log recovery we will have a perag structure 306 * attached, but the agf information will not yet have been initialised 307 * from the on disk AGF. Again, we can only check against maximum limits 308 * in this case. 309 */ 310 if (!xfs_verify_magic(bp, block->bb_magic)) 311 return __this_address; 312 313 if (!xfs_sb_version_hasrmapbt(&mp->m_sb)) 314 return __this_address; 315 fa = xfs_btree_sblock_v5hdr_verify(bp); 316 if (fa) 317 return fa; 318 319 level = be16_to_cpu(block->bb_level); 320 if (pag && pag->pagf_init) { 321 if (level >= pag->pagf_levels[XFS_BTNUM_RMAPi]) 322 return __this_address; 323 } else if (level >= mp->m_rmap_maxlevels) 324 return __this_address; 325 326 return xfs_btree_sblock_verify(bp, mp->m_rmap_mxr[level != 0]); 327 } 328 329 static void 330 xfs_rmapbt_read_verify( 331 struct xfs_buf *bp) 332 { 333 xfs_failaddr_t fa; 334 335 if (!xfs_btree_sblock_verify_crc(bp)) 336 xfs_verifier_error(bp, -EFSBADCRC, __this_address); 337 else { 338 fa = xfs_rmapbt_verify(bp); 339 if (fa) 340 xfs_verifier_error(bp, -EFSCORRUPTED, fa); 341 } 342 343 if (bp->b_error) 344 trace_xfs_btree_corrupt(bp, _RET_IP_); 345 } 346 347 static void 348 xfs_rmapbt_write_verify( 349 struct xfs_buf *bp) 350 { 351 xfs_failaddr_t fa; 352 353 fa = xfs_rmapbt_verify(bp); 354 if (fa) { 355 trace_xfs_btree_corrupt(bp, _RET_IP_); 356 xfs_verifier_error(bp, -EFSCORRUPTED, fa); 357 return; 358 } 359 xfs_btree_sblock_calc_crc(bp); 360 361 } 362 363 const struct xfs_buf_ops xfs_rmapbt_buf_ops = { 364 .name = "xfs_rmapbt", 365 .magic = { 0, cpu_to_be32(XFS_RMAP_CRC_MAGIC) }, 366 .verify_read = xfs_rmapbt_read_verify, 367 .verify_write = xfs_rmapbt_write_verify, 368 .verify_struct = xfs_rmapbt_verify, 369 }; 370 371 STATIC int 372 xfs_rmapbt_keys_inorder( 373 struct xfs_btree_cur *cur, 374 union xfs_btree_key *k1, 375 union xfs_btree_key *k2) 376 { 377 uint32_t x; 378 uint32_t y; 379 uint64_t a; 380 uint64_t b; 381 382 x = be32_to_cpu(k1->rmap.rm_startblock); 383 y = be32_to_cpu(k2->rmap.rm_startblock); 384 if (x < y) 385 return 1; 386 else if (x > y) 387 return 0; 388 a = be64_to_cpu(k1->rmap.rm_owner); 389 b = be64_to_cpu(k2->rmap.rm_owner); 390 if (a < b) 391 return 1; 392 else if (a > b) 393 return 0; 394 a = XFS_RMAP_OFF(be64_to_cpu(k1->rmap.rm_offset)); 395 b = XFS_RMAP_OFF(be64_to_cpu(k2->rmap.rm_offset)); 396 if (a <= b) 397 return 1; 398 return 0; 399 } 400 401 STATIC int 402 xfs_rmapbt_recs_inorder( 403 struct xfs_btree_cur *cur, 404 union xfs_btree_rec *r1, 405 union xfs_btree_rec *r2) 406 { 407 uint32_t x; 408 uint32_t y; 409 uint64_t a; 410 uint64_t b; 411 412 x = be32_to_cpu(r1->rmap.rm_startblock); 413 y = be32_to_cpu(r2->rmap.rm_startblock); 414 if (x < y) 415 return 1; 416 else if (x > y) 417 return 0; 418 a = be64_to_cpu(r1->rmap.rm_owner); 419 b = be64_to_cpu(r2->rmap.rm_owner); 420 if (a < b) 421 return 1; 422 else if (a > b) 423 return 0; 424 a = XFS_RMAP_OFF(be64_to_cpu(r1->rmap.rm_offset)); 425 b = XFS_RMAP_OFF(be64_to_cpu(r2->rmap.rm_offset)); 426 if (a <= b) 427 return 1; 428 return 0; 429 } 430 431 static const struct xfs_btree_ops xfs_rmapbt_ops = { 432 .rec_len = sizeof(struct xfs_rmap_rec), 433 .key_len = 2 * sizeof(struct xfs_rmap_key), 434 435 .dup_cursor = xfs_rmapbt_dup_cursor, 436 .set_root = xfs_rmapbt_set_root, 437 .alloc_block = xfs_rmapbt_alloc_block, 438 .free_block = xfs_rmapbt_free_block, 439 .get_minrecs = xfs_rmapbt_get_minrecs, 440 .get_maxrecs = xfs_rmapbt_get_maxrecs, 441 .init_key_from_rec = xfs_rmapbt_init_key_from_rec, 442 .init_high_key_from_rec = xfs_rmapbt_init_high_key_from_rec, 443 .init_rec_from_cur = xfs_rmapbt_init_rec_from_cur, 444 .init_ptr_from_cur = xfs_rmapbt_init_ptr_from_cur, 445 .key_diff = xfs_rmapbt_key_diff, 446 .buf_ops = &xfs_rmapbt_buf_ops, 447 .diff_two_keys = xfs_rmapbt_diff_two_keys, 448 .keys_inorder = xfs_rmapbt_keys_inorder, 449 .recs_inorder = xfs_rmapbt_recs_inorder, 450 }; 451 452 static struct xfs_btree_cur * 453 xfs_rmapbt_init_common( 454 struct xfs_mount *mp, 455 struct xfs_trans *tp, 456 xfs_agnumber_t agno) 457 { 458 struct xfs_btree_cur *cur; 459 460 cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS); 461 cur->bc_tp = tp; 462 cur->bc_mp = mp; 463 /* Overlapping btree; 2 keys per pointer. */ 464 cur->bc_btnum = XFS_BTNUM_RMAP; 465 cur->bc_flags = XFS_BTREE_CRC_BLOCKS | XFS_BTREE_OVERLAPPING; 466 cur->bc_blocklog = mp->m_sb.sb_blocklog; 467 cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_rmap_2); 468 cur->bc_ag.agno = agno; 469 cur->bc_ops = &xfs_rmapbt_ops; 470 471 return cur; 472 } 473 474 /* Create a new reverse mapping btree cursor. */ 475 struct xfs_btree_cur * 476 xfs_rmapbt_init_cursor( 477 struct xfs_mount *mp, 478 struct xfs_trans *tp, 479 struct xfs_buf *agbp, 480 xfs_agnumber_t agno) 481 { 482 struct xfs_agf *agf = agbp->b_addr; 483 struct xfs_btree_cur *cur; 484 485 cur = xfs_rmapbt_init_common(mp, tp, agno); 486 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]); 487 cur->bc_ag.agbp = agbp; 488 return cur; 489 } 490 491 /* Create a new reverse mapping btree cursor with a fake root for staging. */ 492 struct xfs_btree_cur * 493 xfs_rmapbt_stage_cursor( 494 struct xfs_mount *mp, 495 struct xbtree_afakeroot *afake, 496 xfs_agnumber_t agno) 497 { 498 struct xfs_btree_cur *cur; 499 500 cur = xfs_rmapbt_init_common(mp, NULL, agno); 501 xfs_btree_stage_afakeroot(cur, afake); 502 return cur; 503 } 504 505 /* 506 * Install a new reverse mapping btree root. Caller is responsible for 507 * invalidating and freeing the old btree blocks. 508 */ 509 void 510 xfs_rmapbt_commit_staged_btree( 511 struct xfs_btree_cur *cur, 512 struct xfs_trans *tp, 513 struct xfs_buf *agbp) 514 { 515 struct xfs_agf *agf = agbp->b_addr; 516 struct xbtree_afakeroot *afake = cur->bc_ag.afake; 517 518 ASSERT(cur->bc_flags & XFS_BTREE_STAGING); 519 520 agf->agf_roots[cur->bc_btnum] = cpu_to_be32(afake->af_root); 521 agf->agf_levels[cur->bc_btnum] = cpu_to_be32(afake->af_levels); 522 agf->agf_rmap_blocks = cpu_to_be32(afake->af_blocks); 523 xfs_alloc_log_agf(tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS | 524 XFS_AGF_RMAP_BLOCKS); 525 xfs_btree_commit_afakeroot(cur, tp, agbp, &xfs_rmapbt_ops); 526 } 527 528 /* 529 * Calculate number of records in an rmap btree block. 530 */ 531 int 532 xfs_rmapbt_maxrecs( 533 int blocklen, 534 int leaf) 535 { 536 blocklen -= XFS_RMAP_BLOCK_LEN; 537 538 if (leaf) 539 return blocklen / sizeof(struct xfs_rmap_rec); 540 return blocklen / 541 (2 * sizeof(struct xfs_rmap_key) + sizeof(xfs_rmap_ptr_t)); 542 } 543 544 /* Compute the maximum height of an rmap btree. */ 545 void 546 xfs_rmapbt_compute_maxlevels( 547 struct xfs_mount *mp) 548 { 549 /* 550 * On a non-reflink filesystem, the maximum number of rmap 551 * records is the number of blocks in the AG, hence the max 552 * rmapbt height is log_$maxrecs($agblocks). However, with 553 * reflink each AG block can have up to 2^32 (per the refcount 554 * record format) owners, which means that theoretically we 555 * could face up to 2^64 rmap records. 556 * 557 * That effectively means that the max rmapbt height must be 558 * XFS_BTREE_MAXLEVELS. "Fortunately" we'll run out of AG 559 * blocks to feed the rmapbt long before the rmapbt reaches 560 * maximum height. The reflink code uses ag_resv_critical to 561 * disallow reflinking when less than 10% of the per-AG metadata 562 * block reservation since the fallback is a regular file copy. 563 */ 564 if (xfs_sb_version_hasreflink(&mp->m_sb)) 565 mp->m_rmap_maxlevels = XFS_BTREE_MAXLEVELS; 566 else 567 mp->m_rmap_maxlevels = xfs_btree_compute_maxlevels( 568 mp->m_rmap_mnr, mp->m_sb.sb_agblocks); 569 } 570 571 /* Calculate the refcount btree size for some records. */ 572 xfs_extlen_t 573 xfs_rmapbt_calc_size( 574 struct xfs_mount *mp, 575 unsigned long long len) 576 { 577 return xfs_btree_calc_size(mp->m_rmap_mnr, len); 578 } 579 580 /* 581 * Calculate the maximum refcount btree size. 582 */ 583 xfs_extlen_t 584 xfs_rmapbt_max_size( 585 struct xfs_mount *mp, 586 xfs_agblock_t agblocks) 587 { 588 /* Bail out if we're uninitialized, which can happen in mkfs. */ 589 if (mp->m_rmap_mxr[0] == 0) 590 return 0; 591 592 return xfs_rmapbt_calc_size(mp, agblocks); 593 } 594 595 /* 596 * Figure out how many blocks to reserve and how many are used by this btree. 597 */ 598 int 599 xfs_rmapbt_calc_reserves( 600 struct xfs_mount *mp, 601 struct xfs_trans *tp, 602 xfs_agnumber_t agno, 603 xfs_extlen_t *ask, 604 xfs_extlen_t *used) 605 { 606 struct xfs_buf *agbp; 607 struct xfs_agf *agf; 608 xfs_agblock_t agblocks; 609 xfs_extlen_t tree_len; 610 int error; 611 612 if (!xfs_sb_version_hasrmapbt(&mp->m_sb)) 613 return 0; 614 615 error = xfs_alloc_read_agf(mp, tp, agno, 0, &agbp); 616 if (error) 617 return error; 618 619 agf = agbp->b_addr; 620 agblocks = be32_to_cpu(agf->agf_length); 621 tree_len = be32_to_cpu(agf->agf_rmap_blocks); 622 xfs_trans_brelse(tp, agbp); 623 624 /* 625 * The log is permanently allocated, so the space it occupies will 626 * never be available for the kinds of things that would require btree 627 * expansion. We therefore can pretend the space isn't there. 628 */ 629 if (mp->m_sb.sb_logstart && 630 XFS_FSB_TO_AGNO(mp, mp->m_sb.sb_logstart) == agno) 631 agblocks -= mp->m_sb.sb_logblocks; 632 633 /* Reserve 1% of the AG or enough for 1 block per record. */ 634 *ask += max(agblocks / 100, xfs_rmapbt_max_size(mp, agblocks)); 635 *used += tree_len; 636 637 return error; 638 } 639