fs/xfs/libxfs/xfs_refcount_btree.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2016 Oracle.  All Rights Reserved.
   4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
   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_mount.h"
  13 #include "xfs_btree.h"
  14 #include "xfs_btree_staging.h"
  15 #include "xfs_refcount_btree.h"
  16 #include "xfs_refcount.h"
  17 #include "xfs_alloc.h"
  18 #include "xfs_error.h"
  19 #include "xfs_trace.h"
  20 #include "xfs_trans.h"
  21 #include "xfs_bit.h"
  22 #include "xfs_rmap.h"
  23 #include "xfs_ag.h"
  24
  25 static struct kmem_cache        *xfs_refcountbt_cur_cache;
  26
  27 static struct xfs_btree_cur *
  28 xfs_refcountbt_dup_cursor(
  29         struct xfs_btree_cur    *cur)
  30 {
  31         return xfs_refcountbt_init_cursor(cur->bc_mp, cur->bc_tp,
  32                         cur->bc_ag.agbp, cur->bc_ag.pag);
  33 }
  34
  35 STATIC void
  36 xfs_refcountbt_set_root(
  37         struct xfs_btree_cur            *cur,
  38         const union xfs_btree_ptr       *ptr,
  39         int                             inc)
  40 {
  41         struct xfs_buf          *agbp = cur->bc_ag.agbp;
  42         struct xfs_agf          *agf = agbp->b_addr;
  43         struct xfs_perag        *pag = agbp->b_pag;
  44
  45         ASSERT(ptr->s != 0);
  46
  47         agf->agf_refcount_root = ptr->s;
  48         be32_add_cpu(&agf->agf_refcount_level, inc);
  49         pag->pagf_refcount_level += inc;
  50
  51         xfs_alloc_log_agf(cur->bc_tp, agbp,
  52                         XFS_AGF_REFCOUNT_ROOT | XFS_AGF_REFCOUNT_LEVEL);
  53 }
  54
  55 STATIC int
  56 xfs_refcountbt_alloc_block(
  57         struct xfs_btree_cur            *cur,
  58         const union xfs_btree_ptr       *start,
  59         union xfs_btree_ptr             *new,
  60         int                             *stat)
  61 {
  62         struct xfs_buf          *agbp = cur->bc_ag.agbp;
  63         struct xfs_agf          *agf = agbp->b_addr;
  64         struct xfs_alloc_arg    args;           /* block allocation args */
  65         int                     error;          /* error return value */
  66
  67         memset(&args, 0, sizeof(args));
  68         args.tp = cur->bc_tp;
  69         args.mp = cur->bc_mp;
  70         args.pag = cur->bc_ag.pag;
  71         args.oinfo = XFS_RMAP_OINFO_REFC;
  72         args.minlen = args.maxlen = args.prod = 1;
  73         args.resv = XFS_AG_RESV_METADATA;
  74
  75         error = xfs_alloc_vextent_near_bno(&args,
  76                         XFS_AGB_TO_FSB(args.mp, args.pag->pag_agno,
  77                                         xfs_refc_block(args.mp)));
  78         if (error)
  79                 goto out_error;
  80         trace_xfs_refcountbt_alloc_block(cur->bc_mp, cur->bc_ag.pag->pag_agno,
  81                         args.agbno, 1);
  82         if (args.fsbno == NULLFSBLOCK) {
  83                 *stat = 0;
  84                 return 0;
  85         }
  86         ASSERT(args.agno == cur->bc_ag.pag->pag_agno);
  87         ASSERT(args.len == 1);
  88
  89         new->s = cpu_to_be32(args.agbno);
  90         be32_add_cpu(&agf->agf_refcount_blocks, 1);
  91         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_REFCOUNT_BLOCKS);
  92
  93         *stat = 1;
  94         return 0;
  95
  96 out_error:
  97         return error;
  98 }
  99
 100 STATIC int
 101 xfs_refcountbt_free_block(
 102         struct xfs_btree_cur    *cur,
 103         struct xfs_buf          *bp)
 104 {
 105         struct xfs_mount        *mp = cur->bc_mp;
 106         struct xfs_buf          *agbp = cur->bc_ag.agbp;
 107         struct xfs_agf          *agf = agbp->b_addr;
 108         xfs_fsblock_t           fsbno = XFS_DADDR_TO_FSB(mp, xfs_buf_daddr(bp));
 109
 110         trace_xfs_refcountbt_free_block(cur->bc_mp, cur->bc_ag.pag->pag_agno,
 111                         XFS_FSB_TO_AGBNO(cur->bc_mp, fsbno), 1);
 112         be32_add_cpu(&agf->agf_refcount_blocks, -1);
 113         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_REFCOUNT_BLOCKS);
 114         return xfs_free_extent_later(cur->bc_tp, fsbno, 1,
 115                         &XFS_RMAP_OINFO_REFC, XFS_AG_RESV_METADATA);
 116 }
 117
 118 STATIC int
 119 xfs_refcountbt_get_minrecs(
 120         struct xfs_btree_cur    *cur,
 121         int                     level)
 122 {
 123         return cur->bc_mp->m_refc_mnr[level != 0];
 124 }
 125
 126 STATIC int
 127 xfs_refcountbt_get_maxrecs(
 128         struct xfs_btree_cur    *cur,
 129         int                     level)
 130 {
 131         return cur->bc_mp->m_refc_mxr[level != 0];
 132 }
 133
 134 STATIC void
 135 xfs_refcountbt_init_key_from_rec(
 136         union xfs_btree_key             *key,
 137         const union xfs_btree_rec       *rec)
 138 {
 139         key->refc.rc_startblock = rec->refc.rc_startblock;
 140 }
 141
 142 STATIC void
 143 xfs_refcountbt_init_high_key_from_rec(
 144         union xfs_btree_key             *key,
 145         const union xfs_btree_rec       *rec)
 146 {
 147         __u32                           x;
 148
 149         x = be32_to_cpu(rec->refc.rc_startblock);
 150         x += be32_to_cpu(rec->refc.rc_blockcount) - 1;
 151         key->refc.rc_startblock = cpu_to_be32(x);
 152 }
 153
 154 STATIC void
 155 xfs_refcountbt_init_rec_from_cur(
 156         struct xfs_btree_cur    *cur,
 157         union xfs_btree_rec     *rec)
 158 {
 159         const struct xfs_refcount_irec *irec = &cur->bc_rec.rc;
 160         uint32_t                start;
 161
 162         start = xfs_refcount_encode_startblock(irec->rc_startblock,
 163                         irec->rc_domain);
 164         rec->refc.rc_startblock = cpu_to_be32(start);
 165         rec->refc.rc_blockcount = cpu_to_be32(cur->bc_rec.rc.rc_blockcount);
 166         rec->refc.rc_refcount = cpu_to_be32(cur->bc_rec.rc.rc_refcount);
 167 }
 168
 169 STATIC void
 170 xfs_refcountbt_init_ptr_from_cur(
 171         struct xfs_btree_cur    *cur,
 172         union xfs_btree_ptr     *ptr)
 173 {
 174         struct xfs_agf          *agf = cur->bc_ag.agbp->b_addr;
 175
 176         ASSERT(cur->bc_ag.pag->pag_agno == be32_to_cpu(agf->agf_seqno));
 177
 178         ptr->s = agf->agf_refcount_root;
 179 }
 180
 181 STATIC int64_t
 182 xfs_refcountbt_key_diff(
 183         struct xfs_btree_cur            *cur,
 184         const union xfs_btree_key       *key)
 185 {
 186         const struct xfs_refcount_key   *kp = &key->refc;
 187         const struct xfs_refcount_irec  *irec = &cur->bc_rec.rc;
 188         uint32_t                        start;
 189
 190         start = xfs_refcount_encode_startblock(irec->rc_startblock,
 191                         irec->rc_domain);
 192         return (int64_t)be32_to_cpu(kp->rc_startblock) - start;
 193 }
 194
 195 STATIC int64_t
 196 xfs_refcountbt_diff_two_keys(
 197         struct xfs_btree_cur            *cur,
 198         const union xfs_btree_key       *k1,
 199         const union xfs_btree_key       *k2,
 200         const union xfs_btree_key       *mask)
 201 {
 202         ASSERT(!mask || mask->refc.rc_startblock);
 203
 204         return (int64_t)be32_to_cpu(k1->refc.rc_startblock) -
 205                         be32_to_cpu(k2->refc.rc_startblock);
 206 }
 207
 208 STATIC xfs_failaddr_t
 209 xfs_refcountbt_verify(
 210         struct xfs_buf          *bp)
 211 {
 212         struct xfs_mount        *mp = bp->b_mount;
 213         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 214         struct xfs_perag        *pag = bp->b_pag;
 215         xfs_failaddr_t          fa;
 216         unsigned int            level;
 217
 218         if (!xfs_verify_magic(bp, block->bb_magic))
 219                 return __this_address;
 220
 221         if (!xfs_has_reflink(mp))
 222                 return __this_address;
 223         fa = xfs_btree_sblock_v5hdr_verify(bp);
 224         if (fa)
 225                 return fa;
 226
 227         level = be16_to_cpu(block->bb_level);
 228         if (pag && xfs_perag_initialised_agf(pag)) {
 229                 if (level >= pag->pagf_refcount_level)
 230                         return __this_address;
 231         } else if (level >= mp->m_refc_maxlevels)
 232                 return __this_address;
 233
 234         return xfs_btree_sblock_verify(bp, mp->m_refc_mxr[level != 0]);
 235 }
 236
 237 STATIC void
 238 xfs_refcountbt_read_verify(
 239         struct xfs_buf  *bp)
 240 {
 241         xfs_failaddr_t  fa;
 242
 243         if (!xfs_btree_sblock_verify_crc(bp))
 244                 xfs_verifier_error(bp, -EFSBADCRC, __this_address);
 245         else {
 246                 fa = xfs_refcountbt_verify(bp);
 247                 if (fa)
 248                         xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 249         }
 250
 251         if (bp->b_error)
 252                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 253 }
 254
 255 STATIC void
 256 xfs_refcountbt_write_verify(
 257         struct xfs_buf  *bp)
 258 {
 259         xfs_failaddr_t  fa;
 260
 261         fa = xfs_refcountbt_verify(bp);
 262         if (fa) {
 263                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 264                 xfs_verifier_error(bp, -EFSCORRUPTED, fa);
 265                 return;
 266         }
 267         xfs_btree_sblock_calc_crc(bp);
 268
 269 }
 270
 271 const struct xfs_buf_ops xfs_refcountbt_buf_ops = {
 272         .name                   = "xfs_refcountbt",
 273         .magic                  = { 0, cpu_to_be32(XFS_REFC_CRC_MAGIC) },
 274         .verify_read            = xfs_refcountbt_read_verify,
 275         .verify_write           = xfs_refcountbt_write_verify,
 276         .verify_struct          = xfs_refcountbt_verify,
 277 };
 278
 279 STATIC int
 280 xfs_refcountbt_keys_inorder(
 281         struct xfs_btree_cur            *cur,
 282         const union xfs_btree_key       *k1,
 283         const union xfs_btree_key       *k2)
 284 {
 285         return be32_to_cpu(k1->refc.rc_startblock) <
 286                be32_to_cpu(k2->refc.rc_startblock);
 287 }
 288
 289 STATIC int
 290 xfs_refcountbt_recs_inorder(
 291         struct xfs_btree_cur            *cur,
 292         const union xfs_btree_rec       *r1,
 293         const union xfs_btree_rec       *r2)
 294 {
 295         return  be32_to_cpu(r1->refc.rc_startblock) +
 296                 be32_to_cpu(r1->refc.rc_blockcount) <=
 297                 be32_to_cpu(r2->refc.rc_startblock);
 298 }
 299
 300 STATIC enum xbtree_key_contig
 301 xfs_refcountbt_keys_contiguous(
 302         struct xfs_btree_cur            *cur,
 303         const union xfs_btree_key       *key1,
 304         const union xfs_btree_key       *key2,
 305         const union xfs_btree_key       *mask)
 306 {
 307         ASSERT(!mask || mask->refc.rc_startblock);
 308
 309         return xbtree_key_contig(be32_to_cpu(key1->refc.rc_startblock),
 310                                  be32_to_cpu(key2->refc.rc_startblock));
 311 }
 312
 313 static const struct xfs_btree_ops xfs_refcountbt_ops = {
 314         .rec_len                = sizeof(struct xfs_refcount_rec),
 315         .key_len                = sizeof(struct xfs_refcount_key),
 316
 317         .dup_cursor             = xfs_refcountbt_dup_cursor,
 318         .set_root               = xfs_refcountbt_set_root,
 319         .alloc_block            = xfs_refcountbt_alloc_block,
 320         .free_block             = xfs_refcountbt_free_block,
 321         .get_minrecs            = xfs_refcountbt_get_minrecs,
 322         .get_maxrecs            = xfs_refcountbt_get_maxrecs,
 323         .init_key_from_rec      = xfs_refcountbt_init_key_from_rec,
 324         .init_high_key_from_rec = xfs_refcountbt_init_high_key_from_rec,
 325         .init_rec_from_cur      = xfs_refcountbt_init_rec_from_cur,
 326         .init_ptr_from_cur      = xfs_refcountbt_init_ptr_from_cur,
 327         .key_diff               = xfs_refcountbt_key_diff,
 328         .buf_ops                = &xfs_refcountbt_buf_ops,
 329         .diff_two_keys          = xfs_refcountbt_diff_two_keys,
 330         .keys_inorder           = xfs_refcountbt_keys_inorder,
 331         .recs_inorder           = xfs_refcountbt_recs_inorder,
 332         .keys_contiguous        = xfs_refcountbt_keys_contiguous,
 333 };
 334
 335 /*
 336  * Initialize a new refcount btree cursor.
 337  */
 338 static struct xfs_btree_cur *
 339 xfs_refcountbt_init_common(
 340         struct xfs_mount        *mp,
 341         struct xfs_trans        *tp,
 342         struct xfs_perag        *pag)
 343 {
 344         struct xfs_btree_cur    *cur;
 345
 346         ASSERT(pag->pag_agno < mp->m_sb.sb_agcount);
 347
 348         cur = xfs_btree_alloc_cursor(mp, tp, XFS_BTNUM_REFC,
 349                         mp->m_refc_maxlevels, xfs_refcountbt_cur_cache);
 350         cur->bc_statoff = XFS_STATS_CALC_INDEX(xs_refcbt_2);
 351
 352         cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 353
 354         cur->bc_ag.pag = xfs_perag_hold(pag);
 355         cur->bc_ag.refc.nr_ops = 0;
 356         cur->bc_ag.refc.shape_changes = 0;
 357         cur->bc_ops = &xfs_refcountbt_ops;
 358         return cur;
 359 }
 360
 361 /* Create a btree cursor. */
 362 struct xfs_btree_cur *
 363 xfs_refcountbt_init_cursor(
 364         struct xfs_mount        *mp,
 365         struct xfs_trans        *tp,
 366         struct xfs_buf          *agbp,
 367         struct xfs_perag        *pag)
 368 {
 369         struct xfs_agf          *agf = agbp->b_addr;
 370         struct xfs_btree_cur    *cur;
 371
 372         cur = xfs_refcountbt_init_common(mp, tp, pag);
 373         cur->bc_nlevels = be32_to_cpu(agf->agf_refcount_level);
 374         cur->bc_ag.agbp = agbp;
 375         return cur;
 376 }
 377
 378 /* Create a btree cursor with a fake root for staging. */
 379 struct xfs_btree_cur *
 380 xfs_refcountbt_stage_cursor(
 381         struct xfs_mount        *mp,
 382         struct xbtree_afakeroot *afake,
 383         struct xfs_perag        *pag)
 384 {
 385         struct xfs_btree_cur    *cur;
 386
 387         cur = xfs_refcountbt_init_common(mp, NULL, pag);
 388         xfs_btree_stage_afakeroot(cur, afake);
 389         return cur;
 390 }
 391
 392 /*
 393  * Swap in the new btree root.  Once we pass this point the newly rebuilt btree
 394  * is in place and we have to kill off all the old btree blocks.
 395  */
 396 void
 397 xfs_refcountbt_commit_staged_btree(
 398         struct xfs_btree_cur    *cur,
 399         struct xfs_trans        *tp,
 400         struct xfs_buf          *agbp)
 401 {
 402         struct xfs_agf          *agf = agbp->b_addr;
 403         struct xbtree_afakeroot *afake = cur->bc_ag.afake;
 404
 405         ASSERT(cur->bc_flags & XFS_BTREE_STAGING);
 406
 407         agf->agf_refcount_root = cpu_to_be32(afake->af_root);
 408         agf->agf_refcount_level = cpu_to_be32(afake->af_levels);
 409         agf->agf_refcount_blocks = cpu_to_be32(afake->af_blocks);
 410         xfs_alloc_log_agf(tp, agbp, XFS_AGF_REFCOUNT_BLOCKS |
 411                                     XFS_AGF_REFCOUNT_ROOT |
 412                                     XFS_AGF_REFCOUNT_LEVEL);
 413         xfs_btree_commit_afakeroot(cur, tp, agbp, &xfs_refcountbt_ops);
 414 }
 415
 416 /* Calculate number of records in a refcount btree block. */
 417 static inline unsigned int
 418 xfs_refcountbt_block_maxrecs(
 419         unsigned int            blocklen,
 420         bool                    leaf)
 421 {
 422         if (leaf)
 423                 return blocklen / sizeof(struct xfs_refcount_rec);
 424         return blocklen / (sizeof(struct xfs_refcount_key) +
 425                            sizeof(xfs_refcount_ptr_t));
 426 }
 427
 428 /*
 429  * Calculate the number of records in a refcount btree block.
 430  */
 431 int
 432 xfs_refcountbt_maxrecs(
 433         int                     blocklen,
 434         bool                    leaf)
 435 {
 436         blocklen -= XFS_REFCOUNT_BLOCK_LEN;
 437         return xfs_refcountbt_block_maxrecs(blocklen, leaf);
 438 }
 439
 440 /* Compute the max possible height of the maximally sized refcount btree. */
 441 unsigned int
 442 xfs_refcountbt_maxlevels_ondisk(void)
 443 {
 444         unsigned int            minrecs[2];
 445         unsigned int            blocklen;
 446
 447         blocklen = XFS_MIN_CRC_BLOCKSIZE - XFS_BTREE_SBLOCK_CRC_LEN;
 448
 449         minrecs[0] = xfs_refcountbt_block_maxrecs(blocklen, true) / 2;
 450         minrecs[1] = xfs_refcountbt_block_maxrecs(blocklen, false) / 2;
 451
 452         return xfs_btree_compute_maxlevels(minrecs, XFS_MAX_CRC_AG_BLOCKS);
 453 }
 454
 455 /* Compute the maximum height of a refcount btree. */
 456 void
 457 xfs_refcountbt_compute_maxlevels(
 458         struct xfs_mount                *mp)
 459 {
 460         if (!xfs_has_reflink(mp)) {
 461                 mp->m_refc_maxlevels = 0;
 462                 return;
 463         }
 464
 465         mp->m_refc_maxlevels = xfs_btree_compute_maxlevels(
 466                         mp->m_refc_mnr, mp->m_sb.sb_agblocks);
 467         ASSERT(mp->m_refc_maxlevels <= xfs_refcountbt_maxlevels_ondisk());
 468 }
 469
 470 /* Calculate the refcount btree size for some records. */
 471 xfs_extlen_t
 472 xfs_refcountbt_calc_size(
 473         struct xfs_mount        *mp,
 474         unsigned long long      len)
 475 {
 476         return xfs_btree_calc_size(mp->m_refc_mnr, len);
 477 }
 478
 479 /*
 480  * Calculate the maximum refcount btree size.
 481  */
 482 xfs_extlen_t
 483 xfs_refcountbt_max_size(
 484         struct xfs_mount        *mp,
 485         xfs_agblock_t           agblocks)
 486 {
 487         /* Bail out if we're uninitialized, which can happen in mkfs. */
 488         if (mp->m_refc_mxr[0] == 0)
 489                 return 0;
 490
 491         return xfs_refcountbt_calc_size(mp, agblocks);
 492 }
 493
 494 /*
 495  * Figure out how many blocks to reserve and how many are used by this btree.
 496  */
 497 int
 498 xfs_refcountbt_calc_reserves(
 499         struct xfs_mount        *mp,
 500         struct xfs_trans        *tp,
 501         struct xfs_perag        *pag,
 502         xfs_extlen_t            *ask,
 503         xfs_extlen_t            *used)
 504 {
 505         struct xfs_buf          *agbp;
 506         struct xfs_agf          *agf;
 507         xfs_agblock_t           agblocks;
 508         xfs_extlen_t            tree_len;
 509         int                     error;
 510
 511         if (!xfs_has_reflink(mp))
 512                 return 0;
 513
 514         error = xfs_alloc_read_agf(pag, tp, 0, &agbp);
 515         if (error)
 516                 return error;
 517
 518         agf = agbp->b_addr;
 519         agblocks = be32_to_cpu(agf->agf_length);
 520         tree_len = be32_to_cpu(agf->agf_refcount_blocks);
 521         xfs_trans_brelse(tp, agbp);
 522
 523         /*
 524          * The log is permanently allocated, so the space it occupies will
 525          * never be available for the kinds of things that would require btree
 526          * expansion.  We therefore can pretend the space isn't there.
 527          */
 528         if (xfs_ag_contains_log(mp, pag->pag_agno))
 529                 agblocks -= mp->m_sb.sb_logblocks;
 530
 531         *ask += xfs_refcountbt_max_size(mp, agblocks);
 532         *used += tree_len;
 533
 534         return error;
 535 }
 536
 537 int __init
 538 xfs_refcountbt_init_cur_cache(void)
 539 {
 540         xfs_refcountbt_cur_cache = kmem_cache_create("xfs_refcbt_cur",
 541                         xfs_btree_cur_sizeof(xfs_refcountbt_maxlevels_ondisk()),
 542                         0, 0, NULL);
 543
 544         if (!xfs_refcountbt_cur_cache)
 545                 return -ENOMEM;
 546         return 0;
 547 }
 548
 549 void
 550 xfs_refcountbt_destroy_cur_cache(void)
 551 {
 552         kmem_cache_destroy(xfs_refcountbt_cur_cache);
 553         xfs_refcountbt_cur_cache = NULL;
 554 }