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_types.h"
  21 #include "xfs_log.h"
  22 #include "xfs_trans.h"
  23 #include "xfs_sb.h"
  24 #include "xfs_ag.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_bmap_btree.h"
  27 #include "xfs_alloc_btree.h"
  28 #include "xfs_ialloc_btree.h"
  29 #include "xfs_dinode.h"
  30 #include "xfs_inode.h"
  31 #include "xfs_btree.h"
  32 #include "xfs_alloc.h"
  33 #include "xfs_extent_busy.h"
  34 #include "xfs_error.h"
  35 #include "xfs_trace.h"
  36 #include "xfs_cksum.h"
  37
  38
  39 STATIC struct xfs_btree_cur *
  40 xfs_allocbt_dup_cursor(
  41         struct xfs_btree_cur    *cur)
  42 {
  43         return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
  44                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
  45                         cur->bc_btnum);
  46 }
  47
  48 STATIC void
  49 xfs_allocbt_set_root(
  50         struct xfs_btree_cur    *cur,
  51         union xfs_btree_ptr     *ptr,
  52         int                     inc)
  53 {
  54         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  55         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
  56         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
  57         int                     btnum = cur->bc_btnum;
  58         struct xfs_perag        *pag = xfs_perag_get(cur->bc_mp, seqno);
  59
  60         ASSERT(ptr->s != 0);
  61
  62         agf->agf_roots[btnum] = ptr->s;
  63         be32_add_cpu(&agf->agf_levels[btnum], inc);
  64         pag->pagf_levels[btnum] += inc;
  65         xfs_perag_put(pag);
  66
  67         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
  68 }
  69
  70 STATIC int
  71 xfs_allocbt_alloc_block(
  72         struct xfs_btree_cur    *cur,
  73         union xfs_btree_ptr     *start,
  74         union xfs_btree_ptr     *new,
  75         int                     length,
  76         int                     *stat)
  77 {
  78         int                     error;
  79         xfs_agblock_t           bno;
  80
  81         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  82
  83         /* Allocate the new block from the freelist. If we can't, give up.  */
  84         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  85                                        &bno, 1);
  86         if (error) {
  87                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  88                 return error;
  89         }
  90
  91         if (bno == NULLAGBLOCK) {
  92                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  93                 *stat = 0;
  94                 return 0;
  95         }
  96
  97         xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
  98
  99         xfs_trans_agbtree_delta(cur->bc_tp, 1);
 100         new->s = cpu_to_be32(bno);
 101
 102         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 103         *stat = 1;
 104         return 0;
 105 }
 106
 107 STATIC int
 108 xfs_allocbt_free_block(
 109         struct xfs_btree_cur    *cur,
 110         struct xfs_buf          *bp)
 111 {
 112         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
 113         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 114         xfs_agblock_t           bno;
 115         int                     error;
 116
 117         bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
 118         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
 119         if (error)
 120                 return error;
 121
 122         xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
 123                               XFS_EXTENT_BUSY_SKIP_DISCARD);
 124         xfs_trans_agbtree_delta(cur->bc_tp, -1);
 125
 126         xfs_trans_binval(cur->bc_tp, bp);
 127         return 0;
 128 }
 129
 130 /*
 131  * Update the longest extent in the AGF
 132  */
 133 STATIC void
 134 xfs_allocbt_update_lastrec(
 135         struct xfs_btree_cur    *cur,
 136         struct xfs_btree_block  *block,
 137         union xfs_btree_rec     *rec,
 138         int                     ptr,
 139         int                     reason)
 140 {
 141         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 142         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 143         struct xfs_perag        *pag;
 144         __be32                  len;
 145         int                     numrecs;
 146
 147         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 148
 149         switch (reason) {
 150         case LASTREC_UPDATE:
 151                 /*
 152                  * If this is the last leaf block and it's the last record,
 153                  * then update the size of the longest extent in the AG.
 154                  */
 155                 if (ptr != xfs_btree_get_numrecs(block))
 156                         return;
 157                 len = rec->alloc.ar_blockcount;
 158                 break;
 159         case LASTREC_INSREC:
 160                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 161                     be32_to_cpu(agf->agf_longest))
 162                         return;
 163                 len = rec->alloc.ar_blockcount;
 164                 break;
 165         case LASTREC_DELREC:
 166                 numrecs = xfs_btree_get_numrecs(block);
 167                 if (ptr <= numrecs)
 168                         return;
 169                 ASSERT(ptr == numrecs + 1);
 170
 171                 if (numrecs) {
 172                         xfs_alloc_rec_t *rrp;
 173
 174                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 175                         len = rrp->ar_blockcount;
 176                 } else {
 177                         len = 0;
 178                 }
 179
 180                 break;
 181         default:
 182                 ASSERT(0);
 183                 return;
 184         }
 185
 186         agf->agf_longest = len;
 187         pag = xfs_perag_get(cur->bc_mp, seqno);
 188         pag->pagf_longest = be32_to_cpu(len);
 189         xfs_perag_put(pag);
 190         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 191 }
 192
 193 STATIC int
 194 xfs_allocbt_get_minrecs(
 195         struct xfs_btree_cur    *cur,
 196         int                     level)
 197 {
 198         return cur->bc_mp->m_alloc_mnr[level != 0];
 199 }
 200
 201 STATIC int
 202 xfs_allocbt_get_maxrecs(
 203         struct xfs_btree_cur    *cur,
 204         int                     level)
 205 {
 206         return cur->bc_mp->m_alloc_mxr[level != 0];
 207 }
 208
 209 STATIC void
 210 xfs_allocbt_init_key_from_rec(
 211         union xfs_btree_key     *key,
 212         union xfs_btree_rec     *rec)
 213 {
 214         ASSERT(rec->alloc.ar_startblock != 0);
 215
 216         key->alloc.ar_startblock = rec->alloc.ar_startblock;
 217         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 218 }
 219
 220 STATIC void
 221 xfs_allocbt_init_rec_from_key(
 222         union xfs_btree_key     *key,
 223         union xfs_btree_rec     *rec)
 224 {
 225         ASSERT(key->alloc.ar_startblock != 0);
 226
 227         rec->alloc.ar_startblock = key->alloc.ar_startblock;
 228         rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
 229 }
 230
 231 STATIC void
 232 xfs_allocbt_init_rec_from_cur(
 233         struct xfs_btree_cur    *cur,
 234         union xfs_btree_rec     *rec)
 235 {
 236         ASSERT(cur->bc_rec.a.ar_startblock != 0);
 237
 238         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 239         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 240 }
 241
 242 STATIC void
 243 xfs_allocbt_init_ptr_from_cur(
 244         struct xfs_btree_cur    *cur,
 245         union xfs_btree_ptr     *ptr)
 246 {
 247         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 248
 249         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 250         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 251
 252         ptr->s = agf->agf_roots[cur->bc_btnum];
 253 }
 254
 255 STATIC __int64_t
 256 xfs_allocbt_key_diff(
 257         struct xfs_btree_cur    *cur,
 258         union xfs_btree_key     *key)
 259 {
 260         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 261         xfs_alloc_key_t         *kp = &key->alloc;
 262         __int64_t               diff;
 263
 264         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 265                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 266                                 rec->ar_startblock;
 267         }
 268
 269         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 270         if (diff)
 271                 return diff;
 272
 273         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 274 }
 275
 276 static bool
 277 xfs_allocbt_verify(
 278         struct xfs_buf          *bp)
 279 {
 280         struct xfs_mount        *mp = bp->b_target->bt_mount;
 281         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 282         struct xfs_perag        *pag = bp->b_pag;
 283         unsigned int            level;
 284
 285         /*
 286          * magic number and level verification
 287          *
 288          * During growfs operations, we can't verify the exact level or owner as
 289          * the perag is not fully initialised and hence not attached to the
 290          * buffer.  In this case, check against the maximum tree depth.
 291          *
 292          * Similarly, during log recovery we will have a perag structure
 293          * attached, but the agf information will not yet have been initialised
 294          * from the on disk AGF. Again, we can only check against maximum limits
 295          * in this case.
 296          */
 297         level = be16_to_cpu(block->bb_level);
 298         switch (block->bb_magic) {
 299         case cpu_to_be32(XFS_ABTB_CRC_MAGIC):
 300                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 301                         return false;
 302                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 303                         return false;
 304                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 305                         return false;
 306                 if (pag &&
 307                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 308                         return false;
 309                 /* fall through */
 310         case cpu_to_be32(XFS_ABTB_MAGIC):
 311                 if (pag && pag->pagf_init) {
 312                         if (level >= pag->pagf_levels[XFS_BTNUM_BNOi])
 313                                 return false;
 314                 } else if (level >= mp->m_ag_maxlevels)
 315                         return false;
 316                 break;
 317         case cpu_to_be32(XFS_ABTC_CRC_MAGIC):
 318                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 319                         return false;
 320                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 321                         return false;
 322                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 323                         return false;
 324                 if (pag &&
 325                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 326                         return false;
 327                 /* fall through */
 328         case cpu_to_be32(XFS_ABTC_MAGIC):
 329                 if (pag && pag->pagf_init) {
 330                         if (level >= pag->pagf_levels[XFS_BTNUM_CNTi])
 331                                 return false;
 332                 } else if (level >= mp->m_ag_maxlevels)
 333                         return false;
 334                 break;
 335         default:
 336                 return false;
 337         }
 338
 339         /* numrecs verification */
 340         if (be16_to_cpu(block->bb_numrecs) > mp->m_alloc_mxr[level != 0])
 341                 return false;
 342
 343         /* sibling pointer verification */
 344         if (!block->bb_u.s.bb_leftsib ||
 345             (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
 346              block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
 347                 return false;
 348         if (!block->bb_u.s.bb_rightsib ||
 349             (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
 350              block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
 351                 return false;
 352
 353         return true;
 354 }
 355
 356 static void
 357 xfs_allocbt_read_verify(
 358         struct xfs_buf  *bp)
 359 {
 360         if (!(xfs_btree_sblock_verify_crc(bp) &&
 361               xfs_allocbt_verify(bp))) {
 362                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 363                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW,
 364                                      bp->b_target->bt_mount, bp->b_addr);
 365                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 366         }
 367 }
 368
 369 static void
 370 xfs_allocbt_write_verify(
 371         struct xfs_buf  *bp)
 372 {
 373         if (!xfs_allocbt_verify(bp)) {
 374                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 375                 XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW,
 376                                      bp->b_target->bt_mount, bp->b_addr);
 377                 xfs_buf_ioerror(bp, EFSCORRUPTED);
 378         }
 379         xfs_btree_sblock_calc_crc(bp);
 380
 381 }
 382
 383 const struct xfs_buf_ops xfs_allocbt_buf_ops = {
 384         .verify_read = xfs_allocbt_read_verify,
 385         .verify_write = xfs_allocbt_write_verify,
 386 };
 387
 388
 389 #if defined(DEBUG) || defined(XFS_WARN)
 390 STATIC int
 391 xfs_allocbt_keys_inorder(
 392         struct xfs_btree_cur    *cur,
 393         union xfs_btree_key     *k1,
 394         union xfs_btree_key     *k2)
 395 {
 396         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 397                 return be32_to_cpu(k1->alloc.ar_startblock) <
 398                        be32_to_cpu(k2->alloc.ar_startblock);
 399         } else {
 400                 return be32_to_cpu(k1->alloc.ar_blockcount) <
 401                         be32_to_cpu(k2->alloc.ar_blockcount) ||
 402                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 403                          be32_to_cpu(k1->alloc.ar_startblock) <
 404                          be32_to_cpu(k2->alloc.ar_startblock));
 405         }
 406 }
 407
 408 STATIC int
 409 xfs_allocbt_recs_inorder(
 410         struct xfs_btree_cur    *cur,
 411         union xfs_btree_rec     *r1,
 412         union xfs_btree_rec     *r2)
 413 {
 414         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 415                 return be32_to_cpu(r1->alloc.ar_startblock) +
 416                         be32_to_cpu(r1->alloc.ar_blockcount) <=
 417                         be32_to_cpu(r2->alloc.ar_startblock);
 418         } else {
 419                 return be32_to_cpu(r1->alloc.ar_blockcount) <
 420                         be32_to_cpu(r2->alloc.ar_blockcount) ||
 421                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 422                          be32_to_cpu(r1->alloc.ar_startblock) <
 423                          be32_to_cpu(r2->alloc.ar_startblock));
 424         }
 425 }
 426 #endif  /* DEBUG */
 427
 428 static const struct xfs_btree_ops xfs_allocbt_ops = {
 429         .rec_len                = sizeof(xfs_alloc_rec_t),
 430         .key_len                = sizeof(xfs_alloc_key_t),
 431
 432         .dup_cursor             = xfs_allocbt_dup_cursor,
 433         .set_root               = xfs_allocbt_set_root,
 434         .alloc_block            = xfs_allocbt_alloc_block,
 435         .free_block             = xfs_allocbt_free_block,
 436         .update_lastrec         = xfs_allocbt_update_lastrec,
 437         .get_minrecs            = xfs_allocbt_get_minrecs,
 438         .get_maxrecs            = xfs_allocbt_get_maxrecs,
 439         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 440         .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
 441         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 442         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 443         .key_diff               = xfs_allocbt_key_diff,
 444         .buf_ops                = &xfs_allocbt_buf_ops,
 445 #if defined(DEBUG) || defined(XFS_WARN)
 446         .keys_inorder           = xfs_allocbt_keys_inorder,
 447         .recs_inorder           = xfs_allocbt_recs_inorder,
 448 #endif
 449 };
 450
 451 /*
 452  * Allocate a new allocation btree cursor.
 453  */
 454 struct xfs_btree_cur *                  /* new alloc btree cursor */
 455 xfs_allocbt_init_cursor(
 456         struct xfs_mount        *mp,            /* file system mount point */
 457         struct xfs_trans        *tp,            /* transaction pointer */
 458         struct xfs_buf          *agbp,          /* buffer for agf structure */
 459         xfs_agnumber_t          agno,           /* allocation group number */
 460         xfs_btnum_t             btnum)          /* btree identifier */
 461 {
 462         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 463         struct xfs_btree_cur    *cur;
 464
 465         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 466
 467         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 468
 469         cur->bc_tp = tp;
 470         cur->bc_mp = mp;
 471         cur->bc_btnum = btnum;
 472         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 473         cur->bc_ops = &xfs_allocbt_ops;
 474
 475         if (btnum == XFS_BTNUM_CNT) {
 476                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
 477                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 478         } else {
 479                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
 480         }
 481
 482         cur->bc_private.a.agbp = agbp;
 483         cur->bc_private.a.agno = agno;
 484
 485         if (xfs_sb_version_hascrc(&mp->m_sb))
 486                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 487
 488         return cur;
 489 }
 490
 491 /*
 492  * Calculate number of records in an alloc btree block.
 493  */
 494 int
 495 xfs_allocbt_maxrecs(
 496         struct xfs_mount        *mp,
 497         int                     blocklen,
 498         int                     leaf)
 499 {
 500         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 501
 502         if (leaf)
 503                 return blocklen / sizeof(xfs_alloc_rec_t);
 504         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 505 }