fs/xfs/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 #include "xfs_fs.h"
  20 #include "xfs_shared.h"
  21 #include "xfs_format.h"
  22 #include "xfs_log_format.h"
  23 #include "xfs_trans_resv.h"
  24 #include "xfs_sb.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                     *stat)
  73 {
  74         int                     error;
  75         xfs_agblock_t           bno;
  76
  77         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  78
  79         /* Allocate the new block from the freelist. If we can't, give up.  */
  80         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  81                                        &bno, 1);
  82         if (error) {
  83                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  84                 return error;
  85         }
  86
  87         if (bno == NULLAGBLOCK) {
  88                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  89                 *stat = 0;
  90                 return 0;
  91         }
  92
  93         xfs_extent_busy_reuse(cur->bc_mp, cur->bc_private.a.agno, bno, 1, false);
  94
  95         xfs_trans_agbtree_delta(cur->bc_tp, 1);
  96         new->s = cpu_to_be32(bno);
  97
  98         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  99         *stat = 1;
 100         return 0;
 101 }
 102
 103 STATIC int
 104 xfs_allocbt_free_block(
 105         struct xfs_btree_cur    *cur,
 106         struct xfs_buf          *bp)
 107 {
 108         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
 109         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 110         xfs_agblock_t           bno;
 111         int                     error;
 112
 113         bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
 114         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
 115         if (error)
 116                 return error;
 117
 118         xfs_extent_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
 119                               XFS_EXTENT_BUSY_SKIP_DISCARD);
 120         xfs_trans_agbtree_delta(cur->bc_tp, -1);
 121         return 0;
 122 }
 123
 124 /*
 125  * Update the longest extent in the AGF
 126  */
 127 STATIC void
 128 xfs_allocbt_update_lastrec(
 129         struct xfs_btree_cur    *cur,
 130         struct xfs_btree_block  *block,
 131         union xfs_btree_rec     *rec,
 132         int                     ptr,
 133         int                     reason)
 134 {
 135         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 136         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 137         struct xfs_perag        *pag;
 138         __be32                  len;
 139         int                     numrecs;
 140
 141         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 142
 143         switch (reason) {
 144         case LASTREC_UPDATE:
 145                 /*
 146                  * If this is the last leaf block and it's the last record,
 147                  * then update the size of the longest extent in the AG.
 148                  */
 149                 if (ptr != xfs_btree_get_numrecs(block))
 150                         return;
 151                 len = rec->alloc.ar_blockcount;
 152                 break;
 153         case LASTREC_INSREC:
 154                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 155                     be32_to_cpu(agf->agf_longest))
 156                         return;
 157                 len = rec->alloc.ar_blockcount;
 158                 break;
 159         case LASTREC_DELREC:
 160                 numrecs = xfs_btree_get_numrecs(block);
 161                 if (ptr <= numrecs)
 162                         return;
 163                 ASSERT(ptr == numrecs + 1);
 164
 165                 if (numrecs) {
 166                         xfs_alloc_rec_t *rrp;
 167
 168                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 169                         len = rrp->ar_blockcount;
 170                 } else {
 171                         len = 0;
 172                 }
 173
 174                 break;
 175         default:
 176                 ASSERT(0);
 177                 return;
 178         }
 179
 180         agf->agf_longest = len;
 181         pag = xfs_perag_get(cur->bc_mp, seqno);
 182         pag->pagf_longest = be32_to_cpu(len);
 183         xfs_perag_put(pag);
 184         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 185 }
 186
 187 STATIC int
 188 xfs_allocbt_get_minrecs(
 189         struct xfs_btree_cur    *cur,
 190         int                     level)
 191 {
 192         return cur->bc_mp->m_alloc_mnr[level != 0];
 193 }
 194
 195 STATIC int
 196 xfs_allocbt_get_maxrecs(
 197         struct xfs_btree_cur    *cur,
 198         int                     level)
 199 {
 200         return cur->bc_mp->m_alloc_mxr[level != 0];
 201 }
 202
 203 STATIC void
 204 xfs_allocbt_init_key_from_rec(
 205         union xfs_btree_key     *key,
 206         union xfs_btree_rec     *rec)
 207 {
 208         ASSERT(rec->alloc.ar_startblock != 0);
 209
 210         key->alloc.ar_startblock = rec->alloc.ar_startblock;
 211         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 212 }
 213
 214 STATIC void
 215 xfs_allocbt_init_rec_from_cur(
 216         struct xfs_btree_cur    *cur,
 217         union xfs_btree_rec     *rec)
 218 {
 219         ASSERT(cur->bc_rec.a.ar_startblock != 0);
 220
 221         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 222         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 223 }
 224
 225 STATIC void
 226 xfs_allocbt_init_ptr_from_cur(
 227         struct xfs_btree_cur    *cur,
 228         union xfs_btree_ptr     *ptr)
 229 {
 230         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 231
 232         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 233         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 234
 235         ptr->s = agf->agf_roots[cur->bc_btnum];
 236 }
 237
 238 STATIC __int64_t
 239 xfs_allocbt_key_diff(
 240         struct xfs_btree_cur    *cur,
 241         union xfs_btree_key     *key)
 242 {
 243         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 244         xfs_alloc_key_t         *kp = &key->alloc;
 245         __int64_t               diff;
 246
 247         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 248                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 249                                 rec->ar_startblock;
 250         }
 251
 252         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 253         if (diff)
 254                 return diff;
 255
 256         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 257 }
 258
 259 static bool
 260 xfs_allocbt_verify(
 261         struct xfs_buf          *bp)
 262 {
 263         struct xfs_mount        *mp = bp->b_target->bt_mount;
 264         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 265         struct xfs_perag        *pag = bp->b_pag;
 266         unsigned int            level;
 267
 268         /*
 269          * magic number and level verification
 270          *
 271          * During growfs operations, we can't verify the exact level or owner as
 272          * the perag is not fully initialised and hence not attached to the
 273          * buffer.  In this case, check against the maximum tree depth.
 274          *
 275          * Similarly, during log recovery we will have a perag structure
 276          * attached, but the agf information will not yet have been initialised
 277          * from the on disk AGF. Again, we can only check against maximum limits
 278          * in this case.
 279          */
 280         level = be16_to_cpu(block->bb_level);
 281         switch (block->bb_magic) {
 282         case cpu_to_be32(XFS_ABTB_CRC_MAGIC):
 283                 if (!xfs_btree_sblock_v5hdr_verify(bp))
 284                         return false;
 285                 /* fall through */
 286         case cpu_to_be32(XFS_ABTB_MAGIC):
 287                 if (pag && pag->pagf_init) {
 288                         if (level >= pag->pagf_levels[XFS_BTNUM_BNOi])
 289                                 return false;
 290                 } else if (level >= mp->m_ag_maxlevels)
 291                         return false;
 292                 break;
 293         case cpu_to_be32(XFS_ABTC_CRC_MAGIC):
 294                 if (!xfs_btree_sblock_v5hdr_verify(bp))
 295                         return false;
 296                 /* fall through */
 297         case cpu_to_be32(XFS_ABTC_MAGIC):
 298                 if (pag && pag->pagf_init) {
 299                         if (level >= pag->pagf_levels[XFS_BTNUM_CNTi])
 300                                 return false;
 301                 } else if (level >= mp->m_ag_maxlevels)
 302                         return false;
 303                 break;
 304         default:
 305                 return false;
 306         }
 307
 308         return xfs_btree_sblock_verify(bp, mp->m_alloc_mxr[level != 0]);
 309 }
 310
 311 static void
 312 xfs_allocbt_read_verify(
 313         struct xfs_buf  *bp)
 314 {
 315         if (!xfs_btree_sblock_verify_crc(bp))
 316                 xfs_buf_ioerror(bp, -EFSBADCRC);
 317         else if (!xfs_allocbt_verify(bp))
 318                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 319
 320         if (bp->b_error) {
 321                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 322                 xfs_verifier_error(bp);
 323         }
 324 }
 325
 326 static void
 327 xfs_allocbt_write_verify(
 328         struct xfs_buf  *bp)
 329 {
 330         if (!xfs_allocbt_verify(bp)) {
 331                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 332                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 333                 xfs_verifier_error(bp);
 334                 return;
 335         }
 336         xfs_btree_sblock_calc_crc(bp);
 337
 338 }
 339
 340 const struct xfs_buf_ops xfs_allocbt_buf_ops = {
 341         .name = "xfs_allocbt",
 342         .verify_read = xfs_allocbt_read_verify,
 343         .verify_write = xfs_allocbt_write_verify,
 344 };
 345
 346
 347 #if defined(DEBUG) || defined(XFS_WARN)
 348 STATIC int
 349 xfs_allocbt_keys_inorder(
 350         struct xfs_btree_cur    *cur,
 351         union xfs_btree_key     *k1,
 352         union xfs_btree_key     *k2)
 353 {
 354         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 355                 return be32_to_cpu(k1->alloc.ar_startblock) <
 356                        be32_to_cpu(k2->alloc.ar_startblock);
 357         } else {
 358                 return be32_to_cpu(k1->alloc.ar_blockcount) <
 359                         be32_to_cpu(k2->alloc.ar_blockcount) ||
 360                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 361                          be32_to_cpu(k1->alloc.ar_startblock) <
 362                          be32_to_cpu(k2->alloc.ar_startblock));
 363         }
 364 }
 365
 366 STATIC int
 367 xfs_allocbt_recs_inorder(
 368         struct xfs_btree_cur    *cur,
 369         union xfs_btree_rec     *r1,
 370         union xfs_btree_rec     *r2)
 371 {
 372         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 373                 return be32_to_cpu(r1->alloc.ar_startblock) +
 374                         be32_to_cpu(r1->alloc.ar_blockcount) <=
 375                         be32_to_cpu(r2->alloc.ar_startblock);
 376         } else {
 377                 return be32_to_cpu(r1->alloc.ar_blockcount) <
 378                         be32_to_cpu(r2->alloc.ar_blockcount) ||
 379                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 380                          be32_to_cpu(r1->alloc.ar_startblock) <
 381                          be32_to_cpu(r2->alloc.ar_startblock));
 382         }
 383 }
 384 #endif  /* DEBUG */
 385
 386 static const struct xfs_btree_ops xfs_allocbt_ops = {
 387         .rec_len                = sizeof(xfs_alloc_rec_t),
 388         .key_len                = sizeof(xfs_alloc_key_t),
 389
 390         .dup_cursor             = xfs_allocbt_dup_cursor,
 391         .set_root               = xfs_allocbt_set_root,
 392         .alloc_block            = xfs_allocbt_alloc_block,
 393         .free_block             = xfs_allocbt_free_block,
 394         .update_lastrec         = xfs_allocbt_update_lastrec,
 395         .get_minrecs            = xfs_allocbt_get_minrecs,
 396         .get_maxrecs            = xfs_allocbt_get_maxrecs,
 397         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 398         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 399         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 400         .key_diff               = xfs_allocbt_key_diff,
 401         .buf_ops                = &xfs_allocbt_buf_ops,
 402 #if defined(DEBUG) || defined(XFS_WARN)
 403         .keys_inorder           = xfs_allocbt_keys_inorder,
 404         .recs_inorder           = xfs_allocbt_recs_inorder,
 405 #endif
 406 };
 407
 408 /*
 409  * Allocate a new allocation btree cursor.
 410  */
 411 struct xfs_btree_cur *                  /* new alloc btree cursor */
 412 xfs_allocbt_init_cursor(
 413         struct xfs_mount        *mp,            /* file system mount point */
 414         struct xfs_trans        *tp,            /* transaction pointer */
 415         struct xfs_buf          *agbp,          /* buffer for agf structure */
 416         xfs_agnumber_t          agno,           /* allocation group number */
 417         xfs_btnum_t             btnum)          /* btree identifier */
 418 {
 419         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 420         struct xfs_btree_cur    *cur;
 421
 422         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 423
 424         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
 425
 426         cur->bc_tp = tp;
 427         cur->bc_mp = mp;
 428         cur->bc_btnum = btnum;
 429         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 430         cur->bc_ops = &xfs_allocbt_ops;
 431
 432         if (btnum == XFS_BTNUM_CNT) {
 433                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]);
 434                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 435         } else {
 436                 cur->bc_nlevels = be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]);
 437         }
 438
 439         cur->bc_private.a.agbp = agbp;
 440         cur->bc_private.a.agno = agno;
 441
 442         if (xfs_sb_version_hascrc(&mp->m_sb))
 443                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 444
 445         return cur;
 446 }
 447
 448 /*
 449  * Calculate number of records in an alloc btree block.
 450  */
 451 int
 452 xfs_allocbt_maxrecs(
 453         struct xfs_mount        *mp,
 454         int                     blocklen,
 455         int                     leaf)
 456 {
 457         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 458
 459         if (leaf)
 460                 return blocklen / sizeof(xfs_alloc_rec_t);
 461         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 462 }