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