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