git.oblomov.eu Git - linux-2.6/blob - 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_bit.h"
  22 #include "xfs_log.h"
  23 #include "xfs_inum.h"
  24 #include "xfs_trans.h"
  25 #include "xfs_sb.h"
  26 #include "xfs_ag.h"
  27 #include "xfs_dir2.h"
  28 #include "xfs_dmapi.h"
  29 #include "xfs_mount.h"
  30 #include "xfs_bmap_btree.h"
  31 #include "xfs_alloc_btree.h"
  32 #include "xfs_ialloc_btree.h"
  33 #include "xfs_dir2_sf.h"
  34 #include "xfs_attr_sf.h"
  35 #include "xfs_dinode.h"
  36 #include "xfs_inode.h"
  37 #include "xfs_btree.h"
  38 #include "xfs_btree_trace.h"
  39 #include "xfs_ialloc.h"
  40 #include "xfs_alloc.h"
  41 #include "xfs_error.h"
  42
  43
  44 STATIC struct xfs_btree_cur *
  45 xfs_allocbt_dup_cursor(
  46         struct xfs_btree_cur    *cur)
  47 {
  48         return xfs_allocbt_init_cursor(cur->bc_mp, cur->bc_tp,
  49                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
  50                         cur->bc_btnum);
  51 }
  52
  53 STATIC void
  54 xfs_allocbt_set_root(
  55         struct xfs_btree_cur    *cur,
  56         union xfs_btree_ptr     *ptr,
  57         int                     inc)
  58 {
  59         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  60         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
  61         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
  62         int                     btnum = cur->bc_btnum;
  63
  64         ASSERT(ptr->s != 0);
  65
  66         agf->agf_roots[btnum] = ptr->s;
  67         be32_add_cpu(&agf->agf_levels[btnum], inc);
  68         cur->bc_mp->m_perag[seqno].pagf_levels[btnum] += inc;
  69
  70         xfs_alloc_log_agf(cur->bc_tp, agbp, XFS_AGF_ROOTS | XFS_AGF_LEVELS);
  71 }
  72
  73 STATIC int
  74 xfs_allocbt_alloc_block(
  75         struct xfs_btree_cur    *cur,
  76         union xfs_btree_ptr     *start,
  77         union xfs_btree_ptr     *new,
  78         int                     length,
  79         int                     *stat)
  80 {
  81         int                     error;
  82         xfs_agblock_t           bno;
  83
  84         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  85
  86         /* Allocate the new block from the freelist. If we can't, give up.  */
  87         error = xfs_alloc_get_freelist(cur->bc_tp, cur->bc_private.a.agbp,
  88                                        &bno, 1);
  89         if (error) {
  90                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
  91                 return error;
  92         }
  93
  94         if (bno == NULLAGBLOCK) {
  95                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
  96                 *stat = 0;
  97                 return 0;
  98         }
  99
 100         xfs_trans_agbtree_delta(cur->bc_tp, 1);
 101         new->s = cpu_to_be32(bno);
 102
 103         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 104         *stat = 1;
 105         return 0;
 106 }
 107
 108 STATIC int
 109 xfs_allocbt_free_block(
 110         struct xfs_btree_cur    *cur,
 111         struct xfs_buf          *bp)
 112 {
 113         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
 114         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 115         xfs_agblock_t           bno;
 116         int                     error;
 117
 118         bno = xfs_daddr_to_agbno(cur->bc_mp, XFS_BUF_ADDR(bp));
 119         error = xfs_alloc_put_freelist(cur->bc_tp, agbp, NULL, bno, 1);
 120         if (error)
 121                 return error;
 122
 123         /*
 124          * Since blocks move to the free list without the coordination used in
 125          * xfs_bmap_finish, we can't allow block to be available for
 126          * reallocation and non-transaction writing (user data) until we know
 127          * that the transaction that moved it to the free list is permanently
 128          * on disk. We track the blocks by declaring these blocks as "busy";
 129          * the busy list is maintained on a per-ag basis and each transaction
 130          * records which entries should be removed when the iclog commits to
 131          * disk. If a busy block is allocated, the iclog is pushed up to the
 132          * LSN that freed the block.
 133          */
 134         xfs_alloc_mark_busy(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1);
 135         xfs_trans_agbtree_delta(cur->bc_tp, -1);
 136         return 0;
 137 }
 138
 139 /*
 140  * Update the longest extent in the AGF
 141  */
 142 STATIC void
 143 xfs_allocbt_update_lastrec(
 144         struct xfs_btree_cur    *cur,
 145         struct xfs_btree_block  *block,
 146         union xfs_btree_rec     *rec,
 147         int                     ptr,
 148         int                     reason)
 149 {
 150         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 151         xfs_agnumber_t          seqno = be32_to_cpu(agf->agf_seqno);
 152         __be32                  len;
 153         int                     numrecs;
 154
 155         ASSERT(cur->bc_btnum == XFS_BTNUM_CNT);
 156
 157         switch (reason) {
 158         case LASTREC_UPDATE:
 159                 /*
 160                  * If this is the last leaf block and it's the last record,
 161                  * then update the size of the longest extent in the AG.
 162                  */
 163                 if (ptr != xfs_btree_get_numrecs(block))
 164                         return;
 165                 len = rec->alloc.ar_blockcount;
 166                 break;
 167         case LASTREC_INSREC:
 168                 if (be32_to_cpu(rec->alloc.ar_blockcount) <=
 169                     be32_to_cpu(agf->agf_longest))
 170                         return;
 171                 len = rec->alloc.ar_blockcount;
 172                 break;
 173         case LASTREC_DELREC:
 174                 numrecs = xfs_btree_get_numrecs(block);
 175                 if (ptr <= numrecs)
 176                         return;
 177                 ASSERT(ptr == numrecs + 1);
 178
 179                 if (numrecs) {
 180                         xfs_alloc_rec_t *rrp;
 181
 182                         rrp = XFS_ALLOC_REC_ADDR(cur->bc_mp, block, numrecs);
 183                         len = rrp->ar_blockcount;
 184                 } else {
 185                         len = 0;
 186                 }
 187
 188                 break;
 189         default:
 190                 ASSERT(0);
 191                 return;
 192         }
 193
 194         agf->agf_longest = len;
 195         cur->bc_mp->m_perag[seqno].pagf_longest = be32_to_cpu(len);
 196         xfs_alloc_log_agf(cur->bc_tp, cur->bc_private.a.agbp, XFS_AGF_LONGEST);
 197 }
 198
 199 STATIC int
 200 xfs_allocbt_get_minrecs(
 201         struct xfs_btree_cur    *cur,
 202         int                     level)
 203 {
 204         return cur->bc_mp->m_alloc_mnr[level != 0];
 205 }
 206
 207 STATIC int
 208 xfs_allocbt_get_maxrecs(
 209         struct xfs_btree_cur    *cur,
 210         int                     level)
 211 {
 212         return cur->bc_mp->m_alloc_mxr[level != 0];
 213 }
 214
 215 STATIC void
 216 xfs_allocbt_init_key_from_rec(
 217         union xfs_btree_key     *key,
 218         union xfs_btree_rec     *rec)
 219 {
 220         ASSERT(rec->alloc.ar_startblock != 0);
 221
 222         key->alloc.ar_startblock = rec->alloc.ar_startblock;
 223         key->alloc.ar_blockcount = rec->alloc.ar_blockcount;
 224 }
 225
 226 STATIC void
 227 xfs_allocbt_init_rec_from_key(
 228         union xfs_btree_key     *key,
 229         union xfs_btree_rec     *rec)
 230 {
 231         ASSERT(key->alloc.ar_startblock != 0);
 232
 233         rec->alloc.ar_startblock = key->alloc.ar_startblock;
 234         rec->alloc.ar_blockcount = key->alloc.ar_blockcount;
 235 }
 236
 237 STATIC void
 238 xfs_allocbt_init_rec_from_cur(
 239         struct xfs_btree_cur    *cur,
 240         union xfs_btree_rec     *rec)
 241 {
 242         ASSERT(cur->bc_rec.a.ar_startblock != 0);
 243
 244         rec->alloc.ar_startblock = cpu_to_be32(cur->bc_rec.a.ar_startblock);
 245         rec->alloc.ar_blockcount = cpu_to_be32(cur->bc_rec.a.ar_blockcount);
 246 }
 247
 248 STATIC void
 249 xfs_allocbt_init_ptr_from_cur(
 250         struct xfs_btree_cur    *cur,
 251         union xfs_btree_ptr     *ptr)
 252 {
 253         struct xfs_agf          *agf = XFS_BUF_TO_AGF(cur->bc_private.a.agbp);
 254
 255         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agf->agf_seqno));
 256         ASSERT(agf->agf_roots[cur->bc_btnum] != 0);
 257
 258         ptr->s = agf->agf_roots[cur->bc_btnum];
 259 }
 260
 261 STATIC __int64_t
 262 xfs_allocbt_key_diff(
 263         struct xfs_btree_cur    *cur,
 264         union xfs_btree_key     *key)
 265 {
 266         xfs_alloc_rec_incore_t  *rec = &cur->bc_rec.a;
 267         xfs_alloc_key_t         *kp = &key->alloc;
 268         __int64_t               diff;
 269
 270         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 271                 return (__int64_t)be32_to_cpu(kp->ar_startblock) -
 272                                 rec->ar_startblock;
 273         }
 274
 275         diff = (__int64_t)be32_to_cpu(kp->ar_blockcount) - rec->ar_blockcount;
 276         if (diff)
 277                 return diff;
 278
 279         return (__int64_t)be32_to_cpu(kp->ar_startblock) - rec->ar_startblock;
 280 }
 281
 282 STATIC int
 283 xfs_allocbt_kill_root(
 284         struct xfs_btree_cur    *cur,
 285         struct xfs_buf          *bp,
 286         int                     level,
 287         union xfs_btree_ptr     *newroot)
 288 {
 289         int                     error;
 290
 291         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
 292         XFS_BTREE_STATS_INC(cur, killroot);
 293
 294         /*
 295          * Update the root pointer, decreasing the level by 1 and then
 296          * free the old root.
 297          */
 298         xfs_allocbt_set_root(cur, newroot, -1);
 299         error = xfs_allocbt_free_block(cur, bp);
 300         if (error) {
 301                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 302                 return error;
 303         }
 304
 305         XFS_BTREE_STATS_INC(cur, free);
 306
 307         xfs_btree_setbuf(cur, level, NULL);
 308         cur->bc_nlevels--;
 309
 310         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 311         return 0;
 312 }
 313
 314 #ifdef DEBUG
 315 STATIC int
 316 xfs_allocbt_keys_inorder(
 317         struct xfs_btree_cur    *cur,
 318         union xfs_btree_key     *k1,
 319         union xfs_btree_key     *k2)
 320 {
 321         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 322                 return be32_to_cpu(k1->alloc.ar_startblock) <
 323                        be32_to_cpu(k2->alloc.ar_startblock);
 324         } else {
 325                 return be32_to_cpu(k1->alloc.ar_blockcount) <
 326                         be32_to_cpu(k2->alloc.ar_blockcount) ||
 327                         (k1->alloc.ar_blockcount == k2->alloc.ar_blockcount &&
 328                          be32_to_cpu(k1->alloc.ar_startblock) <
 329                          be32_to_cpu(k2->alloc.ar_startblock));
 330         }
 331 }
 332
 333 STATIC int
 334 xfs_allocbt_recs_inorder(
 335         struct xfs_btree_cur    *cur,
 336         union xfs_btree_rec     *r1,
 337         union xfs_btree_rec     *r2)
 338 {
 339         if (cur->bc_btnum == XFS_BTNUM_BNO) {
 340                 return be32_to_cpu(r1->alloc.ar_startblock) +
 341                         be32_to_cpu(r1->alloc.ar_blockcount) <=
 342                         be32_to_cpu(r2->alloc.ar_startblock);
 343         } else {
 344                 return be32_to_cpu(r1->alloc.ar_blockcount) <
 345                         be32_to_cpu(r2->alloc.ar_blockcount) ||
 346                         (r1->alloc.ar_blockcount == r2->alloc.ar_blockcount &&
 347                          be32_to_cpu(r1->alloc.ar_startblock) <
 348                          be32_to_cpu(r2->alloc.ar_startblock));
 349         }
 350 }
 351 #endif  /* DEBUG */
 352
 353 #ifdef XFS_BTREE_TRACE
 354 ktrace_t        *xfs_allocbt_trace_buf;
 355
 356 STATIC void
 357 xfs_allocbt_trace_enter(
 358         struct xfs_btree_cur    *cur,
 359         const char              *func,
 360         char                    *s,
 361         int                     type,
 362         int                     line,
 363         __psunsigned_t          a0,
 364         __psunsigned_t          a1,
 365         __psunsigned_t          a2,
 366         __psunsigned_t          a3,
 367         __psunsigned_t          a4,
 368         __psunsigned_t          a5,
 369         __psunsigned_t          a6,
 370         __psunsigned_t          a7,
 371         __psunsigned_t          a8,
 372         __psunsigned_t          a9,
 373         __psunsigned_t          a10)
 374 {
 375         ktrace_enter(xfs_allocbt_trace_buf, (void *)(__psint_t)type,
 376                 (void *)func, (void *)s, NULL, (void *)cur,
 377                 (void *)a0, (void *)a1, (void *)a2, (void *)a3,
 378                 (void *)a4, (void *)a5, (void *)a6, (void *)a7,
 379                 (void *)a8, (void *)a9, (void *)a10);
 380 }
 381
 382 STATIC void
 383 xfs_allocbt_trace_cursor(
 384         struct xfs_btree_cur    *cur,
 385         __uint32_t              *s0,
 386         __uint64_t              *l0,
 387         __uint64_t              *l1)
 388 {
 389         *s0 = cur->bc_private.a.agno;
 390         *l0 = cur->bc_rec.a.ar_startblock;
 391         *l1 = cur->bc_rec.a.ar_blockcount;
 392 }
 393
 394 STATIC void
 395 xfs_allocbt_trace_key(
 396         struct xfs_btree_cur    *cur,
 397         union xfs_btree_key     *key,
 398         __uint64_t              *l0,
 399         __uint64_t              *l1)
 400 {
 401         *l0 = be32_to_cpu(key->alloc.ar_startblock);
 402         *l1 = be32_to_cpu(key->alloc.ar_blockcount);
 403 }
 404
 405 STATIC void
 406 xfs_allocbt_trace_record(
 407         struct xfs_btree_cur    *cur,
 408         union xfs_btree_rec     *rec,
 409         __uint64_t              *l0,
 410         __uint64_t              *l1,
 411         __uint64_t              *l2)
 412 {
 413         *l0 = be32_to_cpu(rec->alloc.ar_startblock);
 414         *l1 = be32_to_cpu(rec->alloc.ar_blockcount);
 415         *l2 = 0;
 416 }
 417 #endif /* XFS_BTREE_TRACE */
 418
 419 static const struct xfs_btree_ops xfs_allocbt_ops = {
 420         .rec_len                = sizeof(xfs_alloc_rec_t),
 421         .key_len                = sizeof(xfs_alloc_key_t),
 422
 423         .dup_cursor             = xfs_allocbt_dup_cursor,
 424         .set_root               = xfs_allocbt_set_root,
 425         .kill_root              = xfs_allocbt_kill_root,
 426         .alloc_block            = xfs_allocbt_alloc_block,
 427         .free_block             = xfs_allocbt_free_block,
 428         .update_lastrec         = xfs_allocbt_update_lastrec,
 429         .get_minrecs            = xfs_allocbt_get_minrecs,
 430         .get_maxrecs            = xfs_allocbt_get_maxrecs,
 431         .init_key_from_rec      = xfs_allocbt_init_key_from_rec,
 432         .init_rec_from_key      = xfs_allocbt_init_rec_from_key,
 433         .init_rec_from_cur      = xfs_allocbt_init_rec_from_cur,
 434         .init_ptr_from_cur      = xfs_allocbt_init_ptr_from_cur,
 435         .key_diff               = xfs_allocbt_key_diff,
 436
 437 #ifdef DEBUG
 438         .keys_inorder           = xfs_allocbt_keys_inorder,
 439         .recs_inorder           = xfs_allocbt_recs_inorder,
 440 #endif
 441
 442 #ifdef XFS_BTREE_TRACE
 443         .trace_enter            = xfs_allocbt_trace_enter,
 444         .trace_cursor           = xfs_allocbt_trace_cursor,
 445         .trace_key              = xfs_allocbt_trace_key,
 446         .trace_record           = xfs_allocbt_trace_record,
 447 #endif
 448 };
 449
 450 /*
 451  * Allocate a new allocation btree cursor.
 452  */
 453 struct xfs_btree_cur *                  /* new alloc btree cursor */
 454 xfs_allocbt_init_cursor(
 455         struct xfs_mount        *mp,            /* file system mount point */
 456         struct xfs_trans        *tp,            /* transaction pointer */
 457         struct xfs_buf          *agbp,          /* buffer for agf structure */
 458         xfs_agnumber_t          agno,           /* allocation group number */
 459         xfs_btnum_t             btnum)          /* btree identifier */
 460 {
 461         struct xfs_agf          *agf = XFS_BUF_TO_AGF(agbp);
 462         struct xfs_btree_cur    *cur;
 463
 464         ASSERT(btnum == XFS_BTNUM_BNO || btnum == XFS_BTNUM_CNT);
 465
 466         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 467
 468         cur->bc_tp = tp;
 469         cur->bc_mp = mp;
 470         cur->bc_nlevels = be32_to_cpu(agf->agf_levels[btnum]);
 471         cur->bc_btnum = btnum;
 472         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 473
 474         cur->bc_ops = &xfs_allocbt_ops;
 475         if (btnum == XFS_BTNUM_CNT)
 476                 cur->bc_flags = XFS_BTREE_LASTREC_UPDATE;
 477
 478         cur->bc_private.a.agbp = agbp;
 479         cur->bc_private.a.agno = agno;
 480
 481         return cur;
 482 }
 483
 484 /*
 485  * Calculate number of records in an alloc btree block.
 486  */
 487 int
 488 xfs_allocbt_maxrecs(
 489         struct xfs_mount        *mp,
 490         int                     blocklen,
 491         int                     leaf)
 492 {
 493         blocklen -= XFS_ALLOC_BLOCK_LEN(mp);
 494
 495         if (leaf)
 496                 return blocklen / sizeof(xfs_alloc_rec_t);
 497         return blocklen / (sizeof(xfs_alloc_key_t) + sizeof(xfs_alloc_ptr_t));
 498 }