fs/xfs/libxfs/xfs_ialloc_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_bit.h"
  25 #include "xfs_mount.h"
  26 #include "xfs_inode.h"
  27 #include "xfs_btree.h"
  28 #include "xfs_ialloc.h"
  29 #include "xfs_ialloc_btree.h"
  30 #include "xfs_alloc.h"
  31 #include "xfs_error.h"
  32 #include "xfs_trace.h"
  33 #include "xfs_cksum.h"
  34 #include "xfs_trans.h"
  35
  36
  37 STATIC int
  38 xfs_inobt_get_minrecs(
  39         struct xfs_btree_cur    *cur,
  40         int                     level)
  41 {
  42         return cur->bc_mp->m_inobt_mnr[level != 0];
  43 }
  44
  45 STATIC struct xfs_btree_cur *
  46 xfs_inobt_dup_cursor(
  47         struct xfs_btree_cur    *cur)
  48 {
  49         return xfs_inobt_init_cursor(cur->bc_mp, cur->bc_tp,
  50                         cur->bc_private.a.agbp, cur->bc_private.a.agno,
  51                         cur->bc_btnum);
  52 }
  53
  54 STATIC void
  55 xfs_inobt_set_root(
  56         struct xfs_btree_cur    *cur,
  57         union xfs_btree_ptr     *nptr,
  58         int                     inc)    /* level change */
  59 {
  60         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  61         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
  62
  63         agi->agi_root = nptr->s;
  64         be32_add_cpu(&agi->agi_level, inc);
  65         xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
  66 }
  67
  68 STATIC void
  69 xfs_finobt_set_root(
  70         struct xfs_btree_cur    *cur,
  71         union xfs_btree_ptr     *nptr,
  72         int                     inc)    /* level change */
  73 {
  74         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  75         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
  76
  77         agi->agi_free_root = nptr->s;
  78         be32_add_cpu(&agi->agi_free_level, inc);
  79         xfs_ialloc_log_agi(cur->bc_tp, agbp,
  80                            XFS_AGI_FREE_ROOT | XFS_AGI_FREE_LEVEL);
  81 }
  82
  83 STATIC int
  84 xfs_inobt_alloc_block(
  85         struct xfs_btree_cur    *cur,
  86         union xfs_btree_ptr     *start,
  87         union xfs_btree_ptr     *new,
  88         int                     *stat)
  89 {
  90         xfs_alloc_arg_t         args;           /* block allocation args */
  91         int                     error;          /* error return value */
  92         xfs_agblock_t           sbno = be32_to_cpu(start->s);
  93
  94         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  95
  96         memset(&args, 0, sizeof(args));
  97         args.tp = cur->bc_tp;
  98         args.mp = cur->bc_mp;
  99         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
 100         args.minlen = 1;
 101         args.maxlen = 1;
 102         args.prod = 1;
 103         args.type = XFS_ALLOCTYPE_NEAR_BNO;
 104
 105         error = xfs_alloc_vextent(&args);
 106         if (error) {
 107                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 108                 return error;
 109         }
 110         if (args.fsbno == NULLFSBLOCK) {
 111                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 112                 *stat = 0;
 113                 return 0;
 114         }
 115         ASSERT(args.len == 1);
 116         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 117
 118         new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
 119         *stat = 1;
 120         return 0;
 121 }
 122
 123 STATIC int
 124 xfs_inobt_free_block(
 125         struct xfs_btree_cur    *cur,
 126         struct xfs_buf          *bp)
 127 {
 128         xfs_fsblock_t           fsbno;
 129         int                     error;
 130
 131         fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
 132         error = xfs_free_extent(cur->bc_tp, fsbno, 1);
 133         if (error)
 134                 return error;
 135
 136         xfs_trans_binval(cur->bc_tp, bp);
 137         return error;
 138 }
 139
 140 STATIC int
 141 xfs_inobt_get_maxrecs(
 142         struct xfs_btree_cur    *cur,
 143         int                     level)
 144 {
 145         return cur->bc_mp->m_inobt_mxr[level != 0];
 146 }
 147
 148 STATIC void
 149 xfs_inobt_init_key_from_rec(
 150         union xfs_btree_key     *key,
 151         union xfs_btree_rec     *rec)
 152 {
 153         key->inobt.ir_startino = rec->inobt.ir_startino;
 154 }
 155
 156 STATIC void
 157 xfs_inobt_init_rec_from_key(
 158         union xfs_btree_key     *key,
 159         union xfs_btree_rec     *rec)
 160 {
 161         rec->inobt.ir_startino = key->inobt.ir_startino;
 162 }
 163
 164 STATIC void
 165 xfs_inobt_init_rec_from_cur(
 166         struct xfs_btree_cur    *cur,
 167         union xfs_btree_rec     *rec)
 168 {
 169         rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
 170         if (xfs_sb_version_hassparseinodes(&cur->bc_mp->m_sb)) {
 171                 rec->inobt.ir_u.sp.ir_holemask =
 172                                         cpu_to_be16(cur->bc_rec.i.ir_holemask);
 173                 rec->inobt.ir_u.sp.ir_count = cur->bc_rec.i.ir_count;
 174                 rec->inobt.ir_u.sp.ir_freecount = cur->bc_rec.i.ir_freecount;
 175         } else {
 176                 /* ir_holemask/ir_count not supported on-disk */
 177                 rec->inobt.ir_u.f.ir_freecount =
 178                                         cpu_to_be32(cur->bc_rec.i.ir_freecount);
 179         }
 180         rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
 181 }
 182
 183 /*
 184  * initial value of ptr for lookup
 185  */
 186 STATIC void
 187 xfs_inobt_init_ptr_from_cur(
 188         struct xfs_btree_cur    *cur,
 189         union xfs_btree_ptr     *ptr)
 190 {
 191         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
 192
 193         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
 194
 195         ptr->s = agi->agi_root;
 196 }
 197
 198 STATIC void
 199 xfs_finobt_init_ptr_from_cur(
 200         struct xfs_btree_cur    *cur,
 201         union xfs_btree_ptr     *ptr)
 202 {
 203         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
 204
 205         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
 206         ptr->s = agi->agi_free_root;
 207 }
 208
 209 STATIC __int64_t
 210 xfs_inobt_key_diff(
 211         struct xfs_btree_cur    *cur,
 212         union xfs_btree_key     *key)
 213 {
 214         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
 215                           cur->bc_rec.i.ir_startino;
 216 }
 217
 218 static int
 219 xfs_inobt_verify(
 220         struct xfs_buf          *bp)
 221 {
 222         struct xfs_mount        *mp = bp->b_target->bt_mount;
 223         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 224         struct xfs_perag        *pag = bp->b_pag;
 225         unsigned int            level;
 226
 227         /*
 228          * During growfs operations, we can't verify the exact owner as the
 229          * perag is not fully initialised and hence not attached to the buffer.
 230          *
 231          * Similarly, during log recovery we will have a perag structure
 232          * attached, but the agi information will not yet have been initialised
 233          * from the on disk AGI. We don't currently use any of this information,
 234          * but beware of the landmine (i.e. need to check pag->pagi_init) if we
 235          * ever do.
 236          */
 237         switch (block->bb_magic) {
 238         case cpu_to_be32(XFS_IBT_CRC_MAGIC):
 239         case cpu_to_be32(XFS_FIBT_CRC_MAGIC):
 240                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 241                         return false;
 242                 if (!uuid_equal(&block->bb_u.s.bb_uuid, &mp->m_sb.sb_uuid))
 243                         return false;
 244                 if (block->bb_u.s.bb_blkno != cpu_to_be64(bp->b_bn))
 245                         return false;
 246                 if (pag &&
 247                     be32_to_cpu(block->bb_u.s.bb_owner) != pag->pag_agno)
 248                         return false;
 249                 /* fall through */
 250         case cpu_to_be32(XFS_IBT_MAGIC):
 251         case cpu_to_be32(XFS_FIBT_MAGIC):
 252                 break;
 253         default:
 254                 return 0;
 255         }
 256
 257         /* numrecs and level verification */
 258         level = be16_to_cpu(block->bb_level);
 259         if (level >= mp->m_in_maxlevels)
 260                 return false;
 261         if (be16_to_cpu(block->bb_numrecs) > mp->m_inobt_mxr[level != 0])
 262                 return false;
 263
 264         /* sibling pointer verification */
 265         if (!block->bb_u.s.bb_leftsib ||
 266             (be32_to_cpu(block->bb_u.s.bb_leftsib) >= mp->m_sb.sb_agblocks &&
 267              block->bb_u.s.bb_leftsib != cpu_to_be32(NULLAGBLOCK)))
 268                 return false;
 269         if (!block->bb_u.s.bb_rightsib ||
 270             (be32_to_cpu(block->bb_u.s.bb_rightsib) >= mp->m_sb.sb_agblocks &&
 271              block->bb_u.s.bb_rightsib != cpu_to_be32(NULLAGBLOCK)))
 272                 return false;
 273
 274         return true;
 275 }
 276
 277 static void
 278 xfs_inobt_read_verify(
 279         struct xfs_buf  *bp)
 280 {
 281         if (!xfs_btree_sblock_verify_crc(bp))
 282                 xfs_buf_ioerror(bp, -EFSBADCRC);
 283         else if (!xfs_inobt_verify(bp))
 284                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 285
 286         if (bp->b_error) {
 287                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 288                 xfs_verifier_error(bp);
 289         }
 290 }
 291
 292 static void
 293 xfs_inobt_write_verify(
 294         struct xfs_buf  *bp)
 295 {
 296         if (!xfs_inobt_verify(bp)) {
 297                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 298                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 299                 xfs_verifier_error(bp);
 300                 return;
 301         }
 302         xfs_btree_sblock_calc_crc(bp);
 303
 304 }
 305
 306 const struct xfs_buf_ops xfs_inobt_buf_ops = {
 307         .verify_read = xfs_inobt_read_verify,
 308         .verify_write = xfs_inobt_write_verify,
 309 };
 310
 311 #if defined(DEBUG) || defined(XFS_WARN)
 312 STATIC int
 313 xfs_inobt_keys_inorder(
 314         struct xfs_btree_cur    *cur,
 315         union xfs_btree_key     *k1,
 316         union xfs_btree_key     *k2)
 317 {
 318         return be32_to_cpu(k1->inobt.ir_startino) <
 319                 be32_to_cpu(k2->inobt.ir_startino);
 320 }
 321
 322 STATIC int
 323 xfs_inobt_recs_inorder(
 324         struct xfs_btree_cur    *cur,
 325         union xfs_btree_rec     *r1,
 326         union xfs_btree_rec     *r2)
 327 {
 328         return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
 329                 be32_to_cpu(r2->inobt.ir_startino);
 330 }
 331 #endif  /* DEBUG */
 332
 333 static const struct xfs_btree_ops xfs_inobt_ops = {
 334         .rec_len                = sizeof(xfs_inobt_rec_t),
 335         .key_len                = sizeof(xfs_inobt_key_t),
 336
 337         .dup_cursor             = xfs_inobt_dup_cursor,
 338         .set_root               = xfs_inobt_set_root,
 339         .alloc_block            = xfs_inobt_alloc_block,
 340         .free_block             = xfs_inobt_free_block,
 341         .get_minrecs            = xfs_inobt_get_minrecs,
 342         .get_maxrecs            = xfs_inobt_get_maxrecs,
 343         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
 344         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
 345         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
 346         .init_ptr_from_cur      = xfs_inobt_init_ptr_from_cur,
 347         .key_diff               = xfs_inobt_key_diff,
 348         .buf_ops                = &xfs_inobt_buf_ops,
 349 #if defined(DEBUG) || defined(XFS_WARN)
 350         .keys_inorder           = xfs_inobt_keys_inorder,
 351         .recs_inorder           = xfs_inobt_recs_inorder,
 352 #endif
 353 };
 354
 355 static const struct xfs_btree_ops xfs_finobt_ops = {
 356         .rec_len                = sizeof(xfs_inobt_rec_t),
 357         .key_len                = sizeof(xfs_inobt_key_t),
 358
 359         .dup_cursor             = xfs_inobt_dup_cursor,
 360         .set_root               = xfs_finobt_set_root,
 361         .alloc_block            = xfs_inobt_alloc_block,
 362         .free_block             = xfs_inobt_free_block,
 363         .get_minrecs            = xfs_inobt_get_minrecs,
 364         .get_maxrecs            = xfs_inobt_get_maxrecs,
 365         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
 366         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
 367         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
 368         .init_ptr_from_cur      = xfs_finobt_init_ptr_from_cur,
 369         .key_diff               = xfs_inobt_key_diff,
 370         .buf_ops                = &xfs_inobt_buf_ops,
 371 #if defined(DEBUG) || defined(XFS_WARN)
 372         .keys_inorder           = xfs_inobt_keys_inorder,
 373         .recs_inorder           = xfs_inobt_recs_inorder,
 374 #endif
 375 };
 376
 377 /*
 378  * Allocate a new inode btree cursor.
 379  */
 380 struct xfs_btree_cur *                          /* new inode btree cursor */
 381 xfs_inobt_init_cursor(
 382         struct xfs_mount        *mp,            /* file system mount point */
 383         struct xfs_trans        *tp,            /* transaction pointer */
 384         struct xfs_buf          *agbp,          /* buffer for agi structure */
 385         xfs_agnumber_t          agno,           /* allocation group number */
 386         xfs_btnum_t             btnum)          /* ialloc or free ino btree */
 387 {
 388         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
 389         struct xfs_btree_cur    *cur;
 390
 391         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 392
 393         cur->bc_tp = tp;
 394         cur->bc_mp = mp;
 395         cur->bc_btnum = btnum;
 396         if (btnum == XFS_BTNUM_INO) {
 397                 cur->bc_nlevels = be32_to_cpu(agi->agi_level);
 398                 cur->bc_ops = &xfs_inobt_ops;
 399         } else {
 400                 cur->bc_nlevels = be32_to_cpu(agi->agi_free_level);
 401                 cur->bc_ops = &xfs_finobt_ops;
 402         }
 403
 404         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 405
 406         if (xfs_sb_version_hascrc(&mp->m_sb))
 407                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 408
 409         cur->bc_private.a.agbp = agbp;
 410         cur->bc_private.a.agno = agno;
 411
 412         return cur;
 413 }
 414
 415 /*
 416  * Calculate number of records in an inobt btree block.
 417  */
 418 int
 419 xfs_inobt_maxrecs(
 420         struct xfs_mount        *mp,
 421         int                     blocklen,
 422         int                     leaf)
 423 {
 424         blocklen -= XFS_INOBT_BLOCK_LEN(mp);
 425
 426         if (leaf)
 427                 return blocklen / sizeof(xfs_inobt_rec_t);
 428         return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
 429 }
 430
 431 /*
 432  * Convert the inode record holemask to an inode allocation bitmap. The inode
 433  * allocation bitmap is inode granularity and specifies whether an inode is
 434  * physically allocated on disk (not whether the inode is considered allocated
 435  * or free by the fs).
 436  *
 437  * A bit value of 1 means the inode is allocated, a value of 0 means it is free.
 438  */
 439 uint64_t
 440 xfs_inobt_irec_to_allocmask(
 441         struct xfs_inobt_rec_incore     *rec)
 442 {
 443         uint64_t                        bitmap = 0;
 444         uint64_t                        inodespbit;
 445         int                             nextbit;
 446         uint                            allocbitmap;
 447
 448         /*
 449          * The holemask has 16-bits for a 64 inode record. Therefore each
 450          * holemask bit represents multiple inodes. Create a mask of bits to set
 451          * in the allocmask for each holemask bit.
 452          */
 453         inodespbit = (1 << XFS_INODES_PER_HOLEMASK_BIT) - 1;
 454
 455         /*
 456          * Allocated inodes are represented by 0 bits in holemask. Invert the 0
 457          * bits to 1 and convert to a uint so we can use xfs_next_bit(). Mask
 458          * anything beyond the 16 holemask bits since this casts to a larger
 459          * type.
 460          */
 461         allocbitmap = ~rec->ir_holemask & ((1 << XFS_INOBT_HOLEMASK_BITS) - 1);
 462
 463         /*
 464          * allocbitmap is the inverted holemask so every set bit represents
 465          * allocated inodes. To expand from 16-bit holemask granularity to
 466          * 64-bit (e.g., bit-per-inode), set inodespbit bits in the target
 467          * bitmap for every holemask bit.
 468          */
 469         nextbit = xfs_next_bit(&allocbitmap, 1, 0);
 470         while (nextbit != -1) {
 471                 ASSERT(nextbit < (sizeof(rec->ir_holemask) * NBBY));
 472
 473                 bitmap |= (inodespbit <<
 474                            (nextbit * XFS_INODES_PER_HOLEMASK_BIT));
 475
 476                 nextbit = xfs_next_bit(&allocbitmap, 1, nextbit + 1);
 477         }
 478
 479         return bitmap;
 480 }
 481
 482 #if defined(DEBUG) || defined(XFS_WARN)
 483 /*
 484  * Verify that an in-core inode record has a valid inode count.
 485  */
 486 int
 487 xfs_inobt_rec_check_count(
 488         struct xfs_mount                *mp,
 489         struct xfs_inobt_rec_incore     *rec)
 490 {
 491         int                             inocount = 0;
 492         int                             nextbit = 0;
 493         uint64_t                        allocbmap;
 494         int                             wordsz;
 495
 496         wordsz = sizeof(allocbmap) / sizeof(unsigned int);
 497         allocbmap = xfs_inobt_irec_to_allocmask(rec);
 498
 499         nextbit = xfs_next_bit((uint *) &allocbmap, wordsz, nextbit);
 500         while (nextbit != -1) {
 501                 inocount++;
 502                 nextbit = xfs_next_bit((uint *) &allocbmap, wordsz,
 503                                        nextbit + 1);
 504         }
 505
 506         if (inocount != rec->ir_count)
 507                 return -EFSCORRUPTED;
 508
 509         return 0;
 510 }
 511 #endif  /* DEBUG */