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 "libxfs_priv.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_trace.h"
  32 #include "xfs_cksum.h"
  33 #include "xfs_trans.h"
  34
  35
  36 STATIC int
  37 xfs_inobt_get_minrecs(
  38         struct xfs_btree_cur    *cur,
  39         int                     level)
  40 {
  41         return cur->bc_mp->m_inobt_mnr[level != 0];
  42 }
  43
  44 STATIC struct xfs_btree_cur *
  45 xfs_inobt_dup_cursor(
  46         struct xfs_btree_cur    *cur)
  47 {
  48         return xfs_inobt_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_inobt_set_root(
  55         struct xfs_btree_cur    *cur,
  56         union xfs_btree_ptr     *nptr,
  57         int                     inc)    /* level change */
  58 {
  59         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  60         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
  61
  62         agi->agi_root = nptr->s;
  63         be32_add_cpu(&agi->agi_level, inc);
  64         xfs_ialloc_log_agi(cur->bc_tp, agbp, XFS_AGI_ROOT | XFS_AGI_LEVEL);
  65 }
  66
  67 STATIC void
  68 xfs_finobt_set_root(
  69         struct xfs_btree_cur    *cur,
  70         union xfs_btree_ptr     *nptr,
  71         int                     inc)    /* level change */
  72 {
  73         struct xfs_buf          *agbp = cur->bc_private.a.agbp;
  74         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
  75
  76         agi->agi_free_root = nptr->s;
  77         be32_add_cpu(&agi->agi_free_level, inc);
  78         xfs_ialloc_log_agi(cur->bc_tp, agbp,
  79                            XFS_AGI_FREE_ROOT | XFS_AGI_FREE_LEVEL);
  80 }
  81
  82 STATIC int
  83 xfs_inobt_alloc_block(
  84         struct xfs_btree_cur    *cur,
  85         union xfs_btree_ptr     *start,
  86         union xfs_btree_ptr     *new,
  87         int                     *stat)
  88 {
  89         xfs_alloc_arg_t         args;           /* block allocation args */
  90         int                     error;          /* error return value */
  91         xfs_agblock_t           sbno = be32_to_cpu(start->s);
  92
  93         XFS_BTREE_TRACE_CURSOR(cur, XBT_ENTRY);
  94
  95         memset(&args, 0, sizeof(args));
  96         args.tp = cur->bc_tp;
  97         args.mp = cur->bc_mp;
  98         args.fsbno = XFS_AGB_TO_FSB(args.mp, cur->bc_private.a.agno, sbno);
  99         args.minlen = 1;
 100         args.maxlen = 1;
 101         args.prod = 1;
 102         args.type = XFS_ALLOCTYPE_NEAR_BNO;
 103
 104         error = xfs_alloc_vextent(&args);
 105         if (error) {
 106                 XFS_BTREE_TRACE_CURSOR(cur, XBT_ERROR);
 107                 return error;
 108         }
 109         if (args.fsbno == NULLFSBLOCK) {
 110                 XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 111                 *stat = 0;
 112                 return 0;
 113         }
 114         ASSERT(args.len == 1);
 115         XFS_BTREE_TRACE_CURSOR(cur, XBT_EXIT);
 116
 117         new->s = cpu_to_be32(XFS_FSB_TO_AGBNO(args.mp, args.fsbno));
 118         *stat = 1;
 119         return 0;
 120 }
 121
 122 STATIC int
 123 xfs_inobt_free_block(
 124         struct xfs_btree_cur    *cur,
 125         struct xfs_buf          *bp)
 126 {
 127         xfs_fsblock_t           fsbno;
 128         int                     error;
 129
 130         fsbno = XFS_DADDR_TO_FSB(cur->bc_mp, XFS_BUF_ADDR(bp));
 131         error = xfs_free_extent(cur->bc_tp, fsbno, 1);
 132         if (error)
 133                 return error;
 134
 135         xfs_trans_binval(cur->bc_tp, bp);
 136         return error;
 137 }
 138
 139 STATIC int
 140 xfs_inobt_get_maxrecs(
 141         struct xfs_btree_cur    *cur,
 142         int                     level)
 143 {
 144         return cur->bc_mp->m_inobt_mxr[level != 0];
 145 }
 146
 147 STATIC void
 148 xfs_inobt_init_key_from_rec(
 149         union xfs_btree_key     *key,
 150         union xfs_btree_rec     *rec)
 151 {
 152         key->inobt.ir_startino = rec->inobt.ir_startino;
 153 }
 154
 155 STATIC void
 156 xfs_inobt_init_rec_from_key(
 157         union xfs_btree_key     *key,
 158         union xfs_btree_rec     *rec)
 159 {
 160         rec->inobt.ir_startino = key->inobt.ir_startino;
 161 }
 162
 163 STATIC void
 164 xfs_inobt_init_rec_from_cur(
 165         struct xfs_btree_cur    *cur,
 166         union xfs_btree_rec     *rec)
 167 {
 168         rec->inobt.ir_startino = cpu_to_be32(cur->bc_rec.i.ir_startino);
 169         if (xfs_sb_version_hassparseinodes(&cur->bc_mp->m_sb)) {
 170                 rec->inobt.ir_u.sp.ir_holemask =
 171                                         cpu_to_be16(cur->bc_rec.i.ir_holemask);
 172                 rec->inobt.ir_u.sp.ir_count = cur->bc_rec.i.ir_count;
 173                 rec->inobt.ir_u.sp.ir_freecount = cur->bc_rec.i.ir_freecount;
 174         } else {
 175                 /* ir_holemask/ir_count not supported on-disk */
 176                 rec->inobt.ir_u.f.ir_freecount =
 177                                         cpu_to_be32(cur->bc_rec.i.ir_freecount);
 178         }
 179         rec->inobt.ir_free = cpu_to_be64(cur->bc_rec.i.ir_free);
 180 }
 181
 182 /*
 183  * initial value of ptr for lookup
 184  */
 185 STATIC void
 186 xfs_inobt_init_ptr_from_cur(
 187         struct xfs_btree_cur    *cur,
 188         union xfs_btree_ptr     *ptr)
 189 {
 190         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
 191
 192         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
 193
 194         ptr->s = agi->agi_root;
 195 }
 196
 197 STATIC void
 198 xfs_finobt_init_ptr_from_cur(
 199         struct xfs_btree_cur    *cur,
 200         union xfs_btree_ptr     *ptr)
 201 {
 202         struct xfs_agi          *agi = XFS_BUF_TO_AGI(cur->bc_private.a.agbp);
 203
 204         ASSERT(cur->bc_private.a.agno == be32_to_cpu(agi->agi_seqno));
 205         ptr->s = agi->agi_free_root;
 206 }
 207
 208 STATIC __int64_t
 209 xfs_inobt_key_diff(
 210         struct xfs_btree_cur    *cur,
 211         union xfs_btree_key     *key)
 212 {
 213         return (__int64_t)be32_to_cpu(key->inobt.ir_startino) -
 214                           cur->bc_rec.i.ir_startino;
 215 }
 216
 217 static int
 218 xfs_inobt_verify(
 219         struct xfs_buf          *bp)
 220 {
 221         struct xfs_mount        *mp = bp->b_target->bt_mount;
 222         struct xfs_btree_block  *block = XFS_BUF_TO_BLOCK(bp);
 223         unsigned int            level;
 224
 225         /*
 226          * During growfs operations, we can't verify the exact owner as the
 227          * perag is not fully initialised and hence not attached to the buffer.
 228          *
 229          * Similarly, during log recovery we will have a perag structure
 230          * attached, but the agi information will not yet have been initialised
 231          * from the on disk AGI. We don't currently use any of this information,
 232          * but beware of the landmine (i.e. need to check pag->pagi_init) if we
 233          * ever do.
 234          */
 235         switch (block->bb_magic) {
 236         case cpu_to_be32(XFS_IBT_CRC_MAGIC):
 237         case cpu_to_be32(XFS_FIBT_CRC_MAGIC):
 238                 if (!xfs_sb_version_hascrc(&mp->m_sb))
 239                         return false;
 240                 if (!xfs_btree_sblock_v5hdr_verify(bp))
 241                         return false;
 242                 /* fall through */
 243         case cpu_to_be32(XFS_IBT_MAGIC):
 244         case cpu_to_be32(XFS_FIBT_MAGIC):
 245                 break;
 246         default:
 247                 return 0;
 248         }
 249
 250         /* level verification */
 251         level = be16_to_cpu(block->bb_level);
 252         if (level >= mp->m_in_maxlevels)
 253                 return false;
 254
 255         return xfs_btree_sblock_verify(bp, mp->m_inobt_mxr[level != 0]);
 256 }
 257
 258 static void
 259 xfs_inobt_read_verify(
 260         struct xfs_buf  *bp)
 261 {
 262         if (!xfs_btree_sblock_verify_crc(bp))
 263                 xfs_buf_ioerror(bp, -EFSBADCRC);
 264         else if (!xfs_inobt_verify(bp))
 265                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 266
 267         if (bp->b_error) {
 268                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 269                 xfs_verifier_error(bp);
 270         }
 271 }
 272
 273 static void
 274 xfs_inobt_write_verify(
 275         struct xfs_buf  *bp)
 276 {
 277         if (!xfs_inobt_verify(bp)) {
 278                 trace_xfs_btree_corrupt(bp, _RET_IP_);
 279                 xfs_buf_ioerror(bp, -EFSCORRUPTED);
 280                 xfs_verifier_error(bp);
 281                 return;
 282         }
 283         xfs_btree_sblock_calc_crc(bp);
 284
 285 }
 286
 287 const struct xfs_buf_ops xfs_inobt_buf_ops = {
 288         .name = "xfs_inobt",
 289         .verify_read = xfs_inobt_read_verify,
 290         .verify_write = xfs_inobt_write_verify,
 291 };
 292
 293 #if defined(DEBUG) || defined(XFS_WARN)
 294 STATIC int
 295 xfs_inobt_keys_inorder(
 296         struct xfs_btree_cur    *cur,
 297         union xfs_btree_key     *k1,
 298         union xfs_btree_key     *k2)
 299 {
 300         return be32_to_cpu(k1->inobt.ir_startino) <
 301                 be32_to_cpu(k2->inobt.ir_startino);
 302 }
 303
 304 STATIC int
 305 xfs_inobt_recs_inorder(
 306         struct xfs_btree_cur    *cur,
 307         union xfs_btree_rec     *r1,
 308         union xfs_btree_rec     *r2)
 309 {
 310         return be32_to_cpu(r1->inobt.ir_startino) + XFS_INODES_PER_CHUNK <=
 311                 be32_to_cpu(r2->inobt.ir_startino);
 312 }
 313 #endif  /* DEBUG */
 314
 315 static const struct xfs_btree_ops xfs_inobt_ops = {
 316         .rec_len                = sizeof(xfs_inobt_rec_t),
 317         .key_len                = sizeof(xfs_inobt_key_t),
 318
 319         .dup_cursor             = xfs_inobt_dup_cursor,
 320         .set_root               = xfs_inobt_set_root,
 321         .alloc_block            = xfs_inobt_alloc_block,
 322         .free_block             = xfs_inobt_free_block,
 323         .get_minrecs            = xfs_inobt_get_minrecs,
 324         .get_maxrecs            = xfs_inobt_get_maxrecs,
 325         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
 326         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
 327         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
 328         .init_ptr_from_cur      = xfs_inobt_init_ptr_from_cur,
 329         .key_diff               = xfs_inobt_key_diff,
 330         .buf_ops                = &xfs_inobt_buf_ops,
 331 #if defined(DEBUG) || defined(XFS_WARN)
 332         .keys_inorder           = xfs_inobt_keys_inorder,
 333         .recs_inorder           = xfs_inobt_recs_inorder,
 334 #endif
 335 };
 336
 337 static const struct xfs_btree_ops xfs_finobt_ops = {
 338         .rec_len                = sizeof(xfs_inobt_rec_t),
 339         .key_len                = sizeof(xfs_inobt_key_t),
 340
 341         .dup_cursor             = xfs_inobt_dup_cursor,
 342         .set_root               = xfs_finobt_set_root,
 343         .alloc_block            = xfs_inobt_alloc_block,
 344         .free_block             = xfs_inobt_free_block,
 345         .get_minrecs            = xfs_inobt_get_minrecs,
 346         .get_maxrecs            = xfs_inobt_get_maxrecs,
 347         .init_key_from_rec      = xfs_inobt_init_key_from_rec,
 348         .init_rec_from_key      = xfs_inobt_init_rec_from_key,
 349         .init_rec_from_cur      = xfs_inobt_init_rec_from_cur,
 350         .init_ptr_from_cur      = xfs_finobt_init_ptr_from_cur,
 351         .key_diff               = xfs_inobt_key_diff,
 352         .buf_ops                = &xfs_inobt_buf_ops,
 353 #if defined(DEBUG) || defined(XFS_WARN)
 354         .keys_inorder           = xfs_inobt_keys_inorder,
 355         .recs_inorder           = xfs_inobt_recs_inorder,
 356 #endif
 357 };
 358
 359 /*
 360  * Allocate a new inode btree cursor.
 361  */
 362 struct xfs_btree_cur *                          /* new inode btree cursor */
 363 xfs_inobt_init_cursor(
 364         struct xfs_mount        *mp,            /* file system mount point */
 365         struct xfs_trans        *tp,            /* transaction pointer */
 366         struct xfs_buf          *agbp,          /* buffer for agi structure */
 367         xfs_agnumber_t          agno,           /* allocation group number */
 368         xfs_btnum_t             btnum)          /* ialloc or free ino btree */
 369 {
 370         struct xfs_agi          *agi = XFS_BUF_TO_AGI(agbp);
 371         struct xfs_btree_cur    *cur;
 372
 373         cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_SLEEP);
 374
 375         cur->bc_tp = tp;
 376         cur->bc_mp = mp;
 377         cur->bc_btnum = btnum;
 378         if (btnum == XFS_BTNUM_INO) {
 379                 cur->bc_nlevels = be32_to_cpu(agi->agi_level);
 380                 cur->bc_ops = &xfs_inobt_ops;
 381         } else {
 382                 cur->bc_nlevels = be32_to_cpu(agi->agi_free_level);
 383                 cur->bc_ops = &xfs_finobt_ops;
 384         }
 385
 386         cur->bc_blocklog = mp->m_sb.sb_blocklog;
 387
 388         if (xfs_sb_version_hascrc(&mp->m_sb))
 389                 cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
 390
 391         cur->bc_private.a.agbp = agbp;
 392         cur->bc_private.a.agno = agno;
 393
 394         return cur;
 395 }
 396
 397 /*
 398  * Calculate number of records in an inobt btree block.
 399  */
 400 int
 401 xfs_inobt_maxrecs(
 402         struct xfs_mount        *mp,
 403         int                     blocklen,
 404         int                     leaf)
 405 {
 406         blocklen -= XFS_INOBT_BLOCK_LEN(mp);
 407
 408         if (leaf)
 409                 return blocklen / sizeof(xfs_inobt_rec_t);
 410         return blocklen / (sizeof(xfs_inobt_key_t) + sizeof(xfs_inobt_ptr_t));
 411 }
 412
 413 /*
 414  * Convert the inode record holemask to an inode allocation bitmap. The inode
 415  * allocation bitmap is inode granularity and specifies whether an inode is
 416  * physically allocated on disk (not whether the inode is considered allocated
 417  * or free by the fs).
 418  *
 419  * A bit value of 1 means the inode is allocated, a value of 0 means it is free.
 420  */
 421 uint64_t
 422 xfs_inobt_irec_to_allocmask(
 423         struct xfs_inobt_rec_incore     *rec)
 424 {
 425         uint64_t                        bitmap = 0;
 426         uint64_t                        inodespbit;
 427         int                             nextbit;
 428         uint                            allocbitmap;
 429
 430         /*
 431          * The holemask has 16-bits for a 64 inode record. Therefore each
 432          * holemask bit represents multiple inodes. Create a mask of bits to set
 433          * in the allocmask for each holemask bit.
 434          */
 435         inodespbit = (1 << XFS_INODES_PER_HOLEMASK_BIT) - 1;
 436
 437         /*
 438          * Allocated inodes are represented by 0 bits in holemask. Invert the 0
 439          * bits to 1 and convert to a uint so we can use xfs_next_bit(). Mask
 440          * anything beyond the 16 holemask bits since this casts to a larger
 441          * type.
 442          */
 443         allocbitmap = ~rec->ir_holemask & ((1 << XFS_INOBT_HOLEMASK_BITS) - 1);
 444
 445         /*
 446          * allocbitmap is the inverted holemask so every set bit represents
 447          * allocated inodes. To expand from 16-bit holemask granularity to
 448          * 64-bit (e.g., bit-per-inode), set inodespbit bits in the target
 449          * bitmap for every holemask bit.
 450          */
 451         nextbit = xfs_next_bit(&allocbitmap, 1, 0);
 452         while (nextbit != -1) {
 453                 ASSERT(nextbit < (sizeof(rec->ir_holemask) * NBBY));
 454
 455                 bitmap |= (inodespbit <<
 456                            (nextbit * XFS_INODES_PER_HOLEMASK_BIT));
 457
 458                 nextbit = xfs_next_bit(&allocbitmap, 1, nextbit + 1);
 459         }
 460
 461         return bitmap;
 462 }
 463
 464 #if defined(DEBUG) || defined(XFS_WARN)
 465 /*
 466  * Verify that an in-core inode record has a valid inode count.
 467  */
 468 int
 469 xfs_inobt_rec_check_count(
 470         struct xfs_mount                *mp,
 471         struct xfs_inobt_rec_incore     *rec)
 472 {
 473         int                             inocount = 0;
 474         int                             nextbit = 0;
 475         uint64_t                        allocbmap;
 476         int                             wordsz;
 477
 478         wordsz = sizeof(allocbmap) / sizeof(unsigned int);
 479         allocbmap = xfs_inobt_irec_to_allocmask(rec);
 480
 481         nextbit = xfs_next_bit((uint *) &allocbmap, wordsz, nextbit);
 482         while (nextbit != -1) {
 483                 inocount++;
 484                 nextbit = xfs_next_bit((uint *) &allocbmap, wordsz,
 485                                        nextbit + 1);
 486         }
 487
 488         if (inocount != rec->ir_count)
 489                 return -EFSCORRUPTED;
 490
 491         return 0;
 492 }
 493 #endif  /* DEBUG */