fs/xfs/xfs_alloc_btree.c

   1 /*
   2  * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
   3  * All Rights Reserved.
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public License as
   7  * published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it would be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write the Free Software Foundation,
  16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  17  */
  18 #include "xfs.h"
  19 #include "xfs_fs.h"
  20 #include "xfs_format.h"
  21 #include "xfs_log_format.h"
  22 #include "xfs_trans_resv.h"
  23 #include "xfs_sb.h"
  24 #include "xfs_ag.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_btree.h"
  27 #include "xfs_alloc_btree.h"
  28 #include "xfs_alloc.h"
  29 #include "xfs_extent_busy.h"
  30 #include "xfs_error.h"
  31 #include "xfs_trace.h"
  32 #include "xfs_cksum.h"
  33 #include "xfs_trans.h"
  34
  35
  36 STATIC struct xfs_btree_cur *
  37 xfs_allocbt_dup_cursor(
  38         struct xfs_btree_cur    *cur)
  39 {
  40         return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
  41                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
  42                         cur->bc_btnum);
  43 }
  44
  45 STATIC void
  46 xfs_allocbt_set_root(
  47         struct xfs_btree_cur    *cur,
  48         union xfs_btree_ptr     *ptr,
  49         int                     inc)
  50 {
  51         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  52         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
  53         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
  54         int                     btnum = cur->bc_btnum;
  55         struct xfs_perag        *pag = xfs_perag_get(cur->bc_mp, seqno);
  56
  57         ASSERT(ptr->s != 0);
  58
  59         agf->agf_roots[btnum] = ptr->s;
  60         be32_add_cpu(&agf->agf_levels[btnum], inc);
  61         pag->pagf_levels[btnum] += inc;
  62         xfs_perag_put(pag);
  63
  64         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
  65 }
  66
  67 STATIC int
  68 xfs_allocbt_alloc_block(
  69         struct xfs_btree_cur    *cur,
  70         union xfs_btree_ptr     *start,
  71         union xfs_btree_ptr     *new,
  72         int                     length,
  73         int                     *stat)
  74 {
  75         int                     error;
  76         xfs_agblock_t           bno;
  77
  78         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  79
  80         /* Allocate the new block from the freelist. If we can't, give up.  */
  81         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  82                                        &bno, 1);
  83         if (error) {
  84                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  85                 return error;
  86         }
  87
  88         if (bno == NULLAGBLOCK) {
  89                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  90                 *stat = 0;
  91                 return 0;
  92         }
  93
  94         xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
  95
  96         xfs_trans_agbtree_delta(cur->bc_tp, 1);
  97         new->s = cpu_to_be32(bno);
  98
  99         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 100         *stat = 1;
 101         return 0;
 102 }
 103
 104 STATIC int
 105 xfs_allocbt_free_block(
 106         struct xfs_btree_cur    *cur,
 107         struct xfs_buf          *bp)
 108 {
 109         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
 110         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 111         xfs_agblock_t           bno;
 112         int                     error;
 113
 114         bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
 115         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
 116         if (error)
 117                 return error;
 118
 119         xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
 120                               XFS_EXTENT_BUSY_SKIP_DISCARD);
 121         xfs_trans_agbtree_delta(cur->bc_tp, -1);
 122
 123         xfs_trans_binval(cur->bc_tp, bp);
 124         return 0;
 125 }
 126
 127 /*
 128  * Update the longest extent in the AGF
 129  */
 130 STATIC void
 131 xfs_allocbt_update_lastrec(
 132         struct xfs_btree_cur    *cur,
 133         struct xfs_btree_block  *block,
 134         union xfs_btree_rec     *rec,
 135         int                     ptr,
 136         int                     reason)
 137 {
 138         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 139         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 140         struct xfs_perag        *pag;
 141         __be32                  len;
 142         int                     numrecs;
 143
 144         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 145
 146         switch (reason) {
 147         case LASTREC_UPDATE:
 148                 /*
 149                  * If this is the last leaf block and it's the last record,
 150                  * then update the size of the longest extent in the AG.
 151                  */
 152                 if (ptr != xfs_btree_get_numrecs(block))
 153                         return;
 154                 len = rec->alloc.ar_blockcount;
 155                 break;
 156         case LASTREC_INSREC:
 157                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 158                     be32_to_cpu(agf->agf_longest))
 159                         return;
 160                 len = rec->alloc.ar_blockcount;
 161                 break;
 162         case LASTREC_DELREC:
 163                 numrecs = xfs_btree_get_numrecs(block);
 164                 if (ptr <= numrecs)
 165                         return;
 166                 ASSERT(ptr == numrecs + 1);
 167
 168                 if (numrecs) {
 169                         xfs_alloc_rec_t *rrp;
 170
 171                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 172                         len = rrp->ar_blockcount;
 173                 } else {
 174                         len = 0;
 175                 }
 176
 177                 break;
 178         default:
 179                 ASSERT(0);
 180                 return;
 181         }
 182
 183         agf->agf_longest = len;
 184         pag = xfs_perag_get(cur->bc_mp, seqno);
 185         pag->pagf_longest = be32_to_cpu(len);
 186         xfs_perag_put(pag);
 187         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 188 }
 189
 190 STATIC int
 191 xfs_allocbt_get_minrecs(
 192         struct xfs_btree_cur    *cur,
 193         int                     level)
 194 {
 195         return cur->bc_mp->m_alloc_mnr[level != 0];
 196 }
 197
 198 STATIC int
 199 xfs_allocbt_get_maxrecs(
 200         struct xfs_btree_cur    *cur,
 201         int                     level)
 202 {
 203         return cur->bc_mp->m_alloc_mxr[level != 0];
 204 }
 205
 206 STATIC void
 207 xfs_allocbt_init_key_from_rec(
 208         union xfs_btree_key     *key,
 209         union xfs_btree_rec     *rec)
 210 {
 211         ASSERT(rec->alloc.ar_startblock != 0);
 212
 213         key->alloc.ar_startblock = rec->alloc.ar_startblock;
 214         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 215 }
 216
 217 STATIC void
 218 xfs_allocbt_init_rec_from_key(
 219         union xfs_btree_key     *key,
 220         union xfs_btree_rec     *rec)
 221 {
 222         ASSERT(key->alloc.ar_startblock != 0);
 223
 224         rec->alloc.ar_startblock = key->alloc.ar_startblock;
 225         rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
 226 }
 227
 228 STATIC void
 229 xfs_allocbt_init_rec_from_cur(
 230         struct xfs_btree_cur    *cur,
 231         union xfs_btree_rec     *rec)
 232 {
 233         ASSERT(cur->bc_rec.a.ar_startblock != 0);
 234
 235         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 236         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 237 }
 238
 239 STATIC void
 240 xfs_allocbt_init_ptr_from_cur(
 241         struct xfs_btree_cur    *cur,
 242         union xfs_btree_ptr     *ptr)
 243 {
 244         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 245
 246         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 247         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 248
 249         ptr->s = agf->agf_roots[cur->bc_btnum];
 250 }
 251
 252 STATIC __int64_t
 253 xfs_allocbt_key_diff(
 254         struct xfs_btree_cur    *cur,
 255         union xfs_btree_key     *key)
 256 {
 257         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 258         xfs_alloc_key_t         *kp = &key->alloc;
 259         __int64_t               diff;
 260
 261         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 262                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 263                                 rec->ar_startblock;
 264         }
 265
 266         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 267         if (diff)
 268                 return diff;
 269
 270         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 271 }
 272
 273 static bool
 274 xfs_allocbt_verify(
 275         struct xfs_buf          *bp)
 276 {
 277         struct xfs_mount        *mp = bp->b_target->bt_mount;
 278         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 279         struct xfs_perag        *pag = bp->b_pag;
 280         unsigned int            level;
 281
 282         /*
 283          * magic number and level verification
 284          *
 285          * During growfs operations, we can't verify the exact level or owner as
 286          * the perag is not fully initialised and hence not attached to the
 287          * buffer.  In this case, check against the maximum tree depth.
 288          *
 289          * Similarly, during log recovery we will have a perag structure
 290          * attached, but the agf information will not yet have been initialised
 291          * from the on disk AGF. Again, we can only check against maximum limits
 292          * in this case.
 293          */
 294         level = be16_to_cpu(block->bb_level);
 295         switch (block->bb_magic) {
 296         case cpu_to_be32(XFS_ABTB_CRC_MAGIC):
 297                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 298                         return false;
 299                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 300                         return false;
 301                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 302                         return false;
 303                 if (pag &&
 304                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 305                         return false;
 306                 /* fall through */
 307         case cpu_to_be32(XFS_ABTB_MAGIC):
 308                 if (pag && pag->pagf_init) {
 309                         if (level >= pag->pagf_levels[XFS_BTNUM_BNOi])
 310                                 return false;
 311                 } else if (level >= mp->m_ag_maxlevels)
 312                         return false;
 313                 break;
 314         case cpu_to_be32(XFS_ABTC_CRC_MAGIC):
 315                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 316                         return false;
 317                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 318                         return false;
 319                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 320                         return false;
 321                 if (pag &&
 322                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 323                         return false;
 324                 /* fall through */
 325         case cpu_to_be32(XFS_ABTC_MAGIC):
 326                 if (pag && pag->pagf_init) {
 327                         if (level >= pag->pagf_levels[XFS_BTNUM_CNTi])
 328                                 return false;
 329                 } else if (level >= mp->m_ag_maxlevels)
 330                         return false;
 331                 break;
 332         default:
 333                 return false;
 334         }
 335
 336         /* numrecs verification */
 337         if (be16_to_cpu(block->bb_numrecs) > mp->m_alloc_mxr[level != 0])
 338                 return false;
 339
 340         /* sibling pointer verification */
 341         if (!block->bb_u.s.bb_leftsib ||
 342             (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
 343              block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
 344                 return false;
 345         if (!block->bb_u.s.bb_rightsib ||
 346             (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
 347              block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
 348                 return false;
 349
 350         return true;
 351 }
 352
 353 static void
 354 xfs_allocbt_read_verify(
 355         struct xfs_buf  *bp)
 356 {
 357         if (!(xfs_btree_sblock_verify_crc(bp) &&
 358               xfs_allocbt_verify(bp))) {
 359                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 360                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW,
 361                                      bp->b_target->bt_mount, bp->b_addr);
 362                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 363         }
 364 }
 365
 366 static void
 367 xfs_allocbt_write_verify(
 368         struct xfs_buf  *bp)
 369 {
 370         if (!xfs_allocbt_verify(bp)) {
 371                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 372                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW,
 373                                      bp->b_target->bt_mount, bp->b_addr);
 374                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 375         }
 376         xfs_btree_sblock_calc_crc(bp);
 377
 378 }
 379
 380 const struct xfs_buf_ops xfs_allocbt_buf_ops = {
 381         .verify_read = xfs_allocbt_read_verify,
 382         .verify_write = xfs_allocbt_write_verify,
 383 };
 384
 385
 386 #if defined(DEBUG) || defined(XFS_WARN)
 387 STATIC int
 388 xfs_allocbt_keys_inorder(
 389         struct xfs_btree_cur    *cur,
 390         union xfs_btree_key     *k1,
 391         union xfs_btree_key     *k2)
 392 {
 393         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 394                 return be32_to_cpu(k1->alloc.ar_startblock) <
 395                        be32_to_cpu(k2->alloc.ar_startblock);
 396         } else {
 397                 return be32_to_cpu(k1->alloc.ar_blockcount) <
 398                         be32_to_cpu(k2->alloc.ar_blockcount) ||
 399                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 400                          be32_to_cpu(k1->alloc.ar_startblock) <
 401                          be32_to_cpu(k2->alloc.ar_startblock));
 402         }
 403 }
 404
 405 STATIC int
 406 xfs_allocbt_recs_inorder(
 407         struct xfs_btree_cur    *cur,
 408         union xfs_btree_rec     *r1,
 409         union xfs_btree_rec     *r2)
 410 {
 411         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 412                 return be32_to_cpu(r1->alloc.ar_startblock) +
 413                         be32_to_cpu(r1->alloc.ar_blockcount) <=
 414                         be32_to_cpu(r2->alloc.ar_startblock);
 415         } else {
 416                 return be32_to_cpu(r1->alloc.ar_blockcount) <
 417                         be32_to_cpu(r2->alloc.ar_blockcount) ||
 418                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 419                          be32_to_cpu(r1->alloc.ar_startblock) <
 420                          be32_to_cpu(r2->alloc.ar_startblock));
 421         }
 422 }
 423 #endif  /* DEBUG */
 424
 425 static const struct xfs_btree_ops xfs_allocbt_ops = {
 426         .rec_len                = sizeof(xfs_alloc_rec_t),
 427         .key_len                = sizeof(xfs_alloc_key_t),
 428
 429         .dup_cursor             = xfs_allocbt_dup_cursor,
 430         .set_root               = xfs_allocbt_set_root,
 431         .alloc_block            = xfs_allocbt_alloc_block,
 432         .free_block             = xfs_allocbt_free_block,
 433         .update_lastrec         = xfs_allocbt_update_lastrec,
 434         .get_minrecs            = xfs_allocbt_get_minrecs,
 435         .get_maxrecs            = xfs_allocbt_get_maxrecs,
 436         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 437         .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
 438         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 439         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 440         .key_diff               = xfs_allocbt_key_diff,
 441         .buf_ops                = &xfs_allocbt_buf_ops,
 442 #if defined(DEBUG) || defined(XFS_WARN)
 443         .keys_inorder           = xfs_allocbt_keys_inorder,
 444         .recs_inorder           = xfs_allocbt_recs_inorder,
 445 #endif
 446 };
 447
 448 /*
 449  * Allocate a new allocation btree cursor.
 450  */
 451 struct xfs_btree_cur *                  /* new alloc btree cursor */
 452 xfs_allocbt_init_cursor(
 453         struct xfs_mount        *mp,            /* file system mount point */
 454         struct xfs_trans        *tp,            /* transaction pointer */
 455         struct xfs_buf          *agbp,          /* buffer for agf structure */
 456         xfs_agnumber_t          agno,           /* allocation group number */
 457         xfs_btnum_t             btnum)          /* btree identifier */
 458 {
 459         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 460         struct xfs_btree_cur    *cur;
 461
 462         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 463
 464         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 465
 466         cur->bc_tp = tp;
 467         cur->bc_mp = mp;
 468         cur->bc_btnum = btnum;
 469         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 470         cur->bc_ops = &xfs_allocbt_ops;
 471
 472         if (btnum == XFS_BTNUM_CNT) {
 473                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
 474                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 475         } else {
 476                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
 477         }
 478
 479         cur->bc_private.a.agbp = agbp;
 480         cur->bc_private.a.agno = agno;
 481
 482         if (xfs_sb_version_hascrc(&mp->m_sb))
 483                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 484
 485         return cur;
 486 }
 487
 488 /*
 489  * Calculate number of records in an alloc btree block.
 490  */
 491 int
 492 xfs_allocbt_maxrecs(
 493         struct xfs_mount        *mp,
 494         int                     blocklen,
 495         int                     leaf)
 496 {
 497         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 498
 499         if (leaf)
 500                 return blocklen / sizeof(xfs_alloc_rec_t);
 501         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 502 }