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
  40         ASSERT(ptr->s != 0);
  41
  42         agf->agf_roots[btnum] = ptr->s;
  43         be32_add_cpu(&agf->agf_levels[btnum], inc);
  44         cur->bc_mp->m_perag[seqno].pagf_levels[btnum] += inc;
  45
  46         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
  47 }
  48
  49 STATIC int
  50 xfs_allocbt_alloc_block(
  51         struct xfs_btree_cur    *cur,
  52         union xfs_btree_ptr     *start,
  53         union xfs_btree_ptr     *new,
  54         int                     length,
  55         int                     *stat)
  56 {
  57         int                     error;
  58         xfs_agblock_t           bno;
  59
  60         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  61
  62         /* Allocate the new block from the freelist. If we can't, give up.  */
  63         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  64                                        &bno, 1);
  65         if (error) {
  66                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  67                 return error;
  68         }
  69
  70         if (bno == NULLAGBLOCK) {
  71                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  72                 *stat = 0;
  73                 return 0;
  74         }
  75
  76         xfs_trans_agbtree_delta(cur->bc_tp, 1);
  77         new->s = cpu_to_be32(bno);
  78
  79         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  80         *stat = 1;
  81         return 0;
  82 }
  83
  84 STATIC int
  85 xfs_allocbt_free_block(
  86         struct xfs_btree_cur    *cur,
  87         struct xfs_buf          *bp)
  88 {
  89         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  90         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
  91         xfs_agblock_t           bno;
  92         int                     error;
  93
  94         bno = XFS_DADDR_TO_AGBNO(cur->bc_mp, XFS_BUF_ADDR(bp));
  95         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
  96         if (error)
  97                 return error;
  98
  99         /*
 100          * Since blocks move to the free list without the coordination used in
 101          * xfs_bmap_finish, we can't allow block to be available for
 102          * reallocation and non-transaction writing (user data) until we know
 103          * that the transaction that moved it to the free list is permanently
 104          * on disk. We track the blocks by declaring these blocks as "busy";
 105          * the busy list is maintained on a per-ag basis and each transaction
 106          * records which entries should be removed when the iclog commits to
 107          * disk. If a busy block is allocated, the iclog is pushed up to the
 108          * LSN that freed the block.
 109          */
 110         xfs_alloc_mark_busy(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1);
 111         xfs_trans_agbtree_delta(cur->bc_tp, -1);
 112         return 0;
 113 }
 114
 115 /*
 116  * Update the longest extent in the AGF
 117  */
 118 STATIC void
 119 xfs_allocbt_update_lastrec(
 120         struct xfs_btree_cur    *cur,
 121         struct xfs_btree_block  *block,
 122         union xfs_btree_rec     *rec,
 123         int                     ptr,
 124         int                     reason)
 125 {
 126         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 127         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 128         __be32                  len;
 129         int                     numrecs;
 130
 131         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 132
 133         switch (reason) {
 134         case LASTREC_UPDATE:
 135                 /*
 136                  * If this is the last leaf block and it's the last record,
 137                  * then update the size of the longest extent in the AG.
 138                  */
 139                 if (ptr != xfs_btree_get_numrecs(block))
 140                         return;
 141                 len = rec->alloc.ar_blockcount;
 142                 break;
 143         case LASTREC_INSREC:
 144                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 145                     be32_to_cpu(agf->agf_longest))
 146                         return;
 147                 len = rec->alloc.ar_blockcount;
 148                 break;
 149         case LASTREC_DELREC:
 150                 numrecs = xfs_btree_get_numrecs(block);
 151                 if (ptr <= numrecs)
 152                         return;
 153                 ASSERT(ptr == numrecs + 1);
 154
 155                 if (numrecs) {
 156                         xfs_alloc_rec_t *rrp;
 157
 158                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 159                         len = rrp->ar_blockcount;
 160                 } else {
 161                         len = 0;
 162                 }
 163
 164                 break;
 165         default:
 166                 ASSERT(0);
 167                 return;
 168         }
 169
 170         agf->agf_longest = len;
 171         cur->bc_mp->m_perag[seqno].pagf_longest = be32_to_cpu(len);
 172         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 173 }
 174
 175 STATIC int
 176 xfs_allocbt_get_minrecs(
 177         struct xfs_btree_cur    *cur,
 178         int                     level)
 179 {
 180         return cur->bc_mp->m_alloc_mnr[level != 0];
 181 }
 182
 183 STATIC int
 184 xfs_allocbt_get_maxrecs(
 185         struct xfs_btree_cur    *cur,
 186         int                     level)
 187 {
 188         return cur->bc_mp->m_alloc_mxr[level != 0];
 189 }
 190
 191 STATIC void
 192 xfs_allocbt_init_key_from_rec(
 193         union xfs_btree_key     *key,
 194         union xfs_btree_rec     *rec)
 195 {
 196         ASSERT(rec->alloc.ar_startblock != 0);
 197
 198         key->alloc.ar_startblock = rec->alloc.ar_startblock;
 199         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 200 }
 201
 202 STATIC void
 203 xfs_allocbt_init_rec_from_key(
 204         union xfs_btree_key     *key,
 205         union xfs_btree_rec     *rec)
 206 {
 207         ASSERT(key->alloc.ar_startblock != 0);
 208
 209         rec->alloc.ar_startblock = key->alloc.ar_startblock;
 210         rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
 211 }
 212
 213 STATIC void
 214 xfs_allocbt_init_rec_from_cur(
 215         struct xfs_btree_cur    *cur,
 216         union xfs_btree_rec     *rec)
 217 {
 218         ASSERT(cur->bc_rec.a.ar_startblock != 0);
 219
 220         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 221         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 222 }
 223
 224 STATIC void
 225 xfs_allocbt_init_ptr_from_cur(
 226         struct xfs_btree_cur    *cur,
 227         union xfs_btree_ptr     *ptr)
 228 {
 229         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 230
 231         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 232         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 233
 234         ptr->s = agf->agf_roots[cur->bc_btnum];
 235 }
 236
 237 STATIC __int64_t
 238 xfs_allocbt_key_diff(
 239         struct xfs_btree_cur    *cur,
 240         union xfs_btree_key     *key)
 241 {
 242         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 243         xfs_alloc_key_t         *kp = &key->alloc;
 244         __int64_t               diff;
 245
 246         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 247                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 248                                 rec->ar_startblock;
 249         }
 250
 251         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 252         if (diff)
 253                 return diff;
 254
 255         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 256 }
 257
 258 STATIC int
 259 xfs_allocbt_kill_root(
 260         struct xfs_btree_cur    *cur,
 261         struct xfs_buf          *bp,
 262         int                     level,
 263         union xfs_btree_ptr     *newroot)
 264 {
 265         int                     error;
 266
 267         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
 268         XFS_BTREE_STATS_INC(cur, killroot);
 269
 270         /*
 271          * Update the root pointer, decreasing the level by 1 and then
 272          * free the old root.
 273          */
 274         xfs_allocbt_set_root(cur, newroot, -1);
 275         error = xfs_allocbt_free_block(cur, bp);
 276         if (error) {
 277                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 278                 return error;
 279         }
 280
 281         XFS_BTREE_STATS_INC(cur, free);
 282
 283         xfs_btree_setbuf(cur, level, NULL);
 284         cur->bc_nlevels--;
 285
 286         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 287         return 0;
 288 }
 289
 290 #ifdef DEBUG
 291 STATIC int
 292 xfs_allocbt_keys_inorder(
 293         struct xfs_btree_cur    *cur,
 294         union xfs_btree_key     *k1,
 295         union xfs_btree_key     *k2)
 296 {
 297         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 298                 return be32_to_cpu(k1->alloc.ar_startblock) <
 299                        be32_to_cpu(k2->alloc.ar_startblock);
 300         } else {
 301                 return be32_to_cpu(k1->alloc.ar_blockcount) <
 302                         be32_to_cpu(k2->alloc.ar_blockcount) ||
 303                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 304                          be32_to_cpu(k1->alloc.ar_startblock) <
 305                          be32_to_cpu(k2->alloc.ar_startblock));
 306         }
 307 }
 308
 309 STATIC int
 310 xfs_allocbt_recs_inorder(
 311         struct xfs_btree_cur    *cur,
 312         union xfs_btree_rec     *r1,
 313         union xfs_btree_rec     *r2)
 314 {
 315         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 316                 return be32_to_cpu(r1->alloc.ar_startblock) +
 317                         be32_to_cpu(r1->alloc.ar_blockcount) <=
 318                         be32_to_cpu(r2->alloc.ar_startblock);
 319         } else {
 320                 return be32_to_cpu(r1->alloc.ar_blockcount) <
 321                         be32_to_cpu(r2->alloc.ar_blockcount) ||
 322                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 323                          be32_to_cpu(r1->alloc.ar_startblock) <
 324                          be32_to_cpu(r2->alloc.ar_startblock));
 325         }
 326 }
 327 #endif  /* DEBUG */
 328
 329 #ifdef XFS_BTREE_TRACE
 330 ktrace_t        *xfs_allocbt_trace_buf;
 331
 332 STATIC void
 333 xfs_allocbt_trace_enter(
 334         struct xfs_btree_cur    *cur,
 335         const char              *func,
 336         char                    *s,
 337         int                     type,
 338         int                     line,
 339         __psunsigned_t          a0,
 340         __psunsigned_t          a1,
 341         __psunsigned_t          a2,
 342         __psunsigned_t          a3,
 343         __psunsigned_t          a4,
 344         __psunsigned_t          a5,
 345         __psunsigned_t          a6,
 346         __psunsigned_t          a7,
 347         __psunsigned_t          a8,
 348         __psunsigned_t          a9,
 349         __psunsigned_t          a10)
 350 {
 351         ktrace_enter(xfs_allocbt_trace_buf, (void *)(__psint_t)type,
 352                 (void *)func, (void *)s, NULL, (void *)cur,
 353                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
 354                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
 355                 (void *)a8, (void *)a9, (void *)a10);
 356 }
 357
 358 STATIC void
 359 xfs_allocbt_trace_cursor(
 360         struct xfs_btree_cur    *cur,
 361         __uint32_t              *s0,
 362         __uint64_t              *l0,
 363         __uint64_t              *l1)
 364 {
 365         *s0 = cur->bc_private.a.agno;
 366         *l0 = cur->bc_rec.a.ar_startblock;
 367         *l1 = cur->bc_rec.a.ar_blockcount;
 368 }
 369
 370 STATIC void
 371 xfs_allocbt_trace_key(
 372         struct xfs_btree_cur    *cur,
 373         union xfs_btree_key     *key,
 374         __uint64_t              *l0,
 375         __uint64_t              *l1)
 376 {
 377         *l0 = be32_to_cpu(key->alloc.ar_startblock);
 378         *l1 = be32_to_cpu(key->alloc.ar_blockcount);
 379 }
 380
 381 STATIC void
 382 xfs_allocbt_trace_record(
 383         struct xfs_btree_cur    *cur,
 384         union xfs_btree_rec     *rec,
 385         __uint64_t              *l0,
 386         __uint64_t              *l1,
 387         __uint64_t              *l2)
 388 {
 389         *l0 = be32_to_cpu(rec->alloc.ar_startblock);
 390         *l1 = be32_to_cpu(rec->alloc.ar_blockcount);
 391         *l2 = 0;
 392 }
 393 #endif /* XFS_BTREE_TRACE */
 394
 395 static const struct xfs_btree_ops xfs_allocbt_ops = {
 396         .rec_len                = sizeof(xfs_alloc_rec_t),
 397         .key_len                = sizeof(xfs_alloc_key_t),
 398
 399         .dup_cursor             = xfs_allocbt_dup_cursor,
 400         .set_root               = xfs_allocbt_set_root,
 401         .kill_root              = xfs_allocbt_kill_root,
 402         .alloc_block            = xfs_allocbt_alloc_block,
 403         .free_block             = xfs_allocbt_free_block,
 404         .update_lastrec         = xfs_allocbt_update_lastrec,
 405         .get_minrecs            = xfs_allocbt_get_minrecs,
 406         .get_maxrecs            = xfs_allocbt_get_maxrecs,
 407         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 408         .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
 409         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 410         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 411         .key_diff               = xfs_allocbt_key_diff,
 412
 413 #ifdef DEBUG
 414         .keys_inorder           = xfs_allocbt_keys_inorder,
 415         .recs_inorder           = xfs_allocbt_recs_inorder,
 416 #endif
 417
 418 #ifdef XFS_BTREE_TRACE
 419         .trace_enter            = xfs_allocbt_trace_enter,
 420         .trace_cursor           = xfs_allocbt_trace_cursor,
 421         .trace_key              = xfs_allocbt_trace_key,
 422         .trace_record           = xfs_allocbt_trace_record,
 423 #endif
 424 };
 425
 426 /*
 427  * Allocate a new allocation btree cursor.
 428  */
 429 struct xfs_btree_cur *                  /* new alloc btree cursor */
 430 xfs_allocbt_init_cursor(
 431         struct xfs_mount        *mp,            /* file system mount point */
 432         struct xfs_trans        *tp,            /* transaction pointer */
 433         struct xfs_buf          *agbp,          /* buffer for agf structure */
 434         xfs_agnumber_t          agno,           /* allocation group number */
 435         xfs_btnum_t             btnum)          /* btree identifier */
 436 {
 437         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 438         struct xfs_btree_cur    *cur;
 439
 440         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 441
 442         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 443
 444         cur->bc_tp = tp;
 445         cur->bc_mp = mp;
 446         cur->bc_nlevels = be32_to_cpu(agf->agf_levels[btnum]);
 447         cur->bc_btnum = btnum;
 448         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 449
 450         cur->bc_ops = &xfs_allocbt_ops;
 451         if (btnum == XFS_BTNUM_CNT)
 452                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 453
 454         cur->bc_private.a.agbp = agbp;
 455         cur->bc_private.a.agno = agno;
 456
 457         return cur;
 458 }
 459
 460 /*
 461  * Calculate number of records in an alloc btree block.
 462  */
 463 int
 464 xfs_allocbt_maxrecs(
 465         struct xfs_mount        *mp,
 466         int                     blocklen,
 467         int                     leaf)
 468 {
 469         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 470
 471         if (leaf)
 472                 return blocklen / sizeof(xfs_alloc_rec_t);
 473         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 474 }