fs/xfs/libxfs/xfs_sb.c

   1 /*
   2  * Copyright (c) 2000-2005 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_sb.h"
  26 #include "xfs_mount.h"
  27 #include "xfs_defer.h"
  28 #include "xfs_inode.h"
  29 #include "xfs_ialloc.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 #include "xfs_buf_item.h"
  36 #include "xfs_bmap_btree.h"
  37 #include "xfs_alloc_btree.h"
  38 #include "xfs_ialloc_btree.h"
  39 #include "xfs_log.h"
  40 #include "xfs_rmap_btree.h"
  41
  42 /*
  43  * Physical superblock buffer manipulations. Shared with libxfs in userspace.
  44  */
  45
  46 /*
  47  * Reference counting access wrappers to the perag structures.
  48  * Because we never free per-ag structures, the only thing we
  49  * have to protect against changes is the tree structure itself.
  50  */
  51 struct xfs_perag *
  52 xfs_perag_get(
  53         struct xfs_mount        *mp,
  54         xfs_agnumber_t          agno)
  55 {
  56         struct xfs_perag        *pag;
  57         int                     ref = 0;
  58
  59         rcu_read_lock();
  60         pag = radix_tree_lookup(&mp->m_perag_tree, agno);
  61         if (pag) {
  62                 ASSERT(atomic_read(&pag->pag_ref) >= 0);
  63                 ref = atomic_inc_return(&pag->pag_ref);
  64         }
  65         rcu_read_unlock();
  66         trace_xfs_perag_get(mp, agno, ref, _RET_IP_);
  67         return pag;
  68 }
  69
  70 /*
  71  * search from @first to find the next perag with the given tag set.
  72  */
  73 struct xfs_perag *
  74 xfs_perag_get_tag(
  75         struct xfs_mount        *mp,
  76         xfs_agnumber_t          first,
  77         int                     tag)
  78 {
  79         struct xfs_perag        *pag;
  80         int                     found;
  81         int                     ref;
  82
  83         rcu_read_lock();
  84         found = radix_tree_gang_lookup_tag(&mp->m_perag_tree,
  85                                         (void **)&pag, first, 1, tag);
  86         if (found <= 0) {
  87                 rcu_read_unlock();
  88                 return NULL;
  89         }
  90         ref = atomic_inc_return(&pag->pag_ref);
  91         rcu_read_unlock();
  92         trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_);
  93         return pag;
  94 }
  95
  96 void
  97 xfs_perag_put(
  98         struct xfs_perag        *pag)
  99 {
 100         int     ref;
 101
 102         ASSERT(atomic_read(&pag->pag_ref) > 0);
 103         ref = atomic_dec_return(&pag->pag_ref);
 104         trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_);
 105 }
 106
 107 /*
 108  * Check the validity of the SB found.
 109  */
 110 STATIC int
 111 xfs_mount_validate_sb(
 112         xfs_mount_t     *mp,
 113         xfs_sb_t        *sbp,
 114         bool            check_inprogress,
 115         bool            check_version)
 116 {
 117         if (sbp->sb_magicnum != XFS_SB_MAGIC) {
 118                 xfs_warn(mp, "bad magic number");
 119                 return -EWRONGFS;
 120         }
 121
 122
 123         if (!xfs_sb_good_version(sbp)) {
 124                 xfs_warn(mp, "bad version");
 125                 return -EWRONGFS;
 126         }
 127
 128         /*
 129          * Version 5 superblock feature mask validation. Reject combinations the
 130          * kernel cannot support up front before checking anything else. For
 131          * write validation, we don't need to check feature masks.
 132          */
 133         if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) {
 134                 if (xfs_sb_has_compat_feature(sbp,
 135                                         XFS_SB_FEAT_COMPAT_UNKNOWN)) {
 136                         xfs_warn(mp,
 137 "Superblock has unknown compatible features (0x%x) enabled.",
 138                                 (sbp->sb_features_compat &
 139                                                 XFS_SB_FEAT_COMPAT_UNKNOWN));
 140                         xfs_warn(mp,
 141 "Using a more recent kernel is recommended.");
 142                 }
 143
 144                 if (xfs_sb_has_ro_compat_feature(sbp,
 145                                         XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
 146                         xfs_alert(mp,
 147 "Superblock has unknown read-only compatible features (0x%x) enabled.",
 148                                 (sbp->sb_features_ro_compat &
 149                                                 XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
 150                         if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
 151                                 xfs_warn(mp,
 152 "Attempted to mount read-only compatible filesystem read-write.");
 153                                 xfs_warn(mp,
 154 "Filesystem can only be safely mounted read only.");
 155
 156                                 return -EINVAL;
 157                         }
 158                 }
 159                 if (xfs_sb_has_incompat_feature(sbp,
 160                                         XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
 161                         xfs_warn(mp,
 162 "Superblock has unknown incompatible features (0x%x) enabled.",
 163                                 (sbp->sb_features_incompat &
 164                                                 XFS_SB_FEAT_INCOMPAT_UNKNOWN));
 165                         xfs_warn(mp,
 166 "Filesystem can not be safely mounted by this kernel.");
 167                         return -EINVAL;
 168                 }
 169         } else if (xfs_sb_version_hascrc(sbp)) {
 170                 /*
 171                  * We can't read verify the sb LSN because the read verifier is
 172                  * called before the log is allocated and processed. We know the
 173                  * log is set up before write verifier (!check_version) calls,
 174                  * so just check it here.
 175                  */
 176                 if (!xfs_log_check_lsn(mp, sbp->sb_lsn))
 177                         return -EFSCORRUPTED;
 178         }
 179
 180         if (xfs_sb_version_has_pquotino(sbp)) {
 181                 if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) {
 182                         xfs_notice(mp,
 183                            "Version 5 of Super block has XFS_OQUOTA bits.");
 184                         return -EFSCORRUPTED;
 185                 }
 186         } else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
 187                                 XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) {
 188                         xfs_notice(mp,
 189 "Superblock earlier than Version 5 has XFS_[PQ]UOTA_{ENFD|CHKD} bits.");
 190                         return -EFSCORRUPTED;
 191         }
 192
 193         /*
 194          * Full inode chunks must be aligned to inode chunk size when
 195          * sparse inodes are enabled to support the sparse chunk
 196          * allocation algorithm and prevent overlapping inode records.
 197          */
 198         if (xfs_sb_version_hassparseinodes(sbp)) {
 199                 uint32_t        align;
 200
 201                 align = XFS_INODES_PER_CHUNK * sbp->sb_inodesize
 202                                 >> sbp->sb_blocklog;
 203                 if (sbp->sb_inoalignmt != align) {
 204                         xfs_warn(mp,
 205 "Inode block alignment (%u) must match chunk size (%u) for sparse inodes.",
 206                                  sbp->sb_inoalignmt, align);
 207                         return -EINVAL;
 208                 }
 209         }
 210
 211         if (unlikely(
 212             sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
 213                 xfs_warn(mp,
 214                 "filesystem is marked as having an external log; "
 215                 "specify logdev on the mount command line.");
 216                 return -EINVAL;
 217         }
 218
 219         if (unlikely(
 220             sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
 221                 xfs_warn(mp,
 222                 "filesystem is marked as having an internal log; "
 223                 "do not specify logdev on the mount command line.");
 224                 return -EINVAL;
 225         }
 226
 227         /*
 228          * More sanity checking.  Most of these were stolen directly from
 229          * xfs_repair.
 230          */
 231         if (unlikely(
 232             sbp->sb_agcount <= 0                                        ||
 233             sbp->sb_sectsize < XFS_MIN_SECTORSIZE                       ||
 234             sbp->sb_sectsize > XFS_MAX_SECTORSIZE                       ||
 235             sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG                    ||
 236             sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG                    ||
 237             sbp->sb_sectsize != (1 << sbp->sb_sectlog)                  ||
 238             sbp->sb_blocksize < XFS_MIN_BLOCKSIZE                       ||
 239             sbp->sb_blocksize > XFS_MAX_BLOCKSIZE                       ||
 240             sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG                    ||
 241             sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG                    ||
 242             sbp->sb_blocksize != (1 << sbp->sb_blocklog)                ||
 243             sbp->sb_dirblklog > XFS_MAX_BLOCKSIZE_LOG                   ||
 244             sbp->sb_inodesize < XFS_DINODE_MIN_SIZE                     ||
 245             sbp->sb_inodesize > XFS_DINODE_MAX_SIZE                     ||
 246             sbp->sb_inodelog < XFS_DINODE_MIN_LOG                       ||
 247             sbp->sb_inodelog > XFS_DINODE_MAX_LOG                       ||
 248             sbp->sb_inodesize != (1 << sbp->sb_inodelog)                ||
 249             sbp->sb_logsunit > XLOG_MAX_RECORD_BSIZE                    ||
 250             sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) ||
 251             (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog)   ||
 252             (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE)  ||
 253             (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)  ||
 254             (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */)    ||
 255             sbp->sb_dblocks == 0                                        ||
 256             sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp)                      ||
 257             sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp)                      ||
 258             sbp->sb_shared_vn != 0)) {
 259                 xfs_notice(mp, "SB sanity check failed");
 260                 return -EFSCORRUPTED;
 261         }
 262
 263         /*
 264          * Until this is fixed only page-sized or smaller data blocks work.
 265          */
 266         if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
 267                 xfs_warn(mp,
 268                 "File system with blocksize %d bytes. "
 269                 "Only pagesize (%ld) or less will currently work.",
 270                                 sbp->sb_blocksize, PAGE_SIZE);
 271                 return -ENOSYS;
 272         }
 273
 274         /*
 275          * Currently only very few inode sizes are supported.
 276          */
 277         switch (sbp->sb_inodesize) {
 278         case 256:
 279         case 512:
 280         case 1024:
 281         case 2048:
 282                 break;
 283         default:
 284                 xfs_warn(mp, "inode size of %d bytes not supported",
 285                                 sbp->sb_inodesize);
 286                 return -ENOSYS;
 287         }
 288
 289         if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
 290             xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
 291                 xfs_warn(mp,
 292                 "file system too large to be mounted on this system.");
 293                 return -EFBIG;
 294         }
 295
 296         if (check_inprogress && sbp->sb_inprogress) {
 297                 xfs_warn(mp, "Offline file system operation in progress!");
 298                 return -EFSCORRUPTED;
 299         }
 300         return 0;
 301 }
 302
 303 void
 304 xfs_sb_quota_from_disk(struct xfs_sb *sbp)
 305 {
 306         /*
 307          * older mkfs doesn't initialize quota inodes to NULLFSINO. This
 308          * leads to in-core values having two different values for a quota
 309          * inode to be invalid: 0 and NULLFSINO. Change it to a single value
 310          * NULLFSINO.
 311          *
 312          * Note that this change affect only the in-core values. These
 313          * values are not written back to disk unless any quota information
 314          * is written to the disk. Even in that case, sb_pquotino field is
 315          * not written to disk unless the superblock supports pquotino.
 316          */
 317         if (sbp->sb_uquotino == 0)
 318                 sbp->sb_uquotino = NULLFSINO;
 319         if (sbp->sb_gquotino == 0)
 320                 sbp->sb_gquotino = NULLFSINO;
 321         if (sbp->sb_pquotino == 0)
 322                 sbp->sb_pquotino = NULLFSINO;
 323
 324         /*
 325          * We need to do these manipilations only if we are working
 326          * with an older version of on-disk superblock.
 327          */
 328         if (xfs_sb_version_has_pquotino(sbp))
 329                 return;
 330
 331         if (sbp->sb_qflags & XFS_OQUOTA_ENFD)
 332                 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
 333                                         XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD;
 334         if (sbp->sb_qflags & XFS_OQUOTA_CHKD)
 335                 sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
 336                                         XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD;
 337         sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD);
 338
 339         if (sbp->sb_qflags & XFS_PQUOTA_ACCT)  {
 340                 /*
 341                  * In older version of superblock, on-disk superblock only
 342                  * has sb_gquotino, and in-core superblock has both sb_gquotino
 343                  * and sb_pquotino. But, only one of them is supported at any
 344                  * point of time. So, if PQUOTA is set in disk superblock,
 345                  * copy over sb_gquotino to sb_pquotino.
 346                  */
 347                 sbp->sb_pquotino = sbp->sb_gquotino;
 348                 sbp->sb_gquotino = NULLFSINO;
 349         }
 350 }
 351
 352 static void
 353 __xfs_sb_from_disk(
 354         struct xfs_sb   *to,
 355         xfs_dsb_t       *from,
 356         bool            convert_xquota)
 357 {
 358         to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
 359         to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
 360         to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
 361         to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
 362         to->sb_rextents = be64_to_cpu(from->sb_rextents);
 363         memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
 364         to->sb_logstart = be64_to_cpu(from->sb_logstart);
 365         to->sb_rootino = be64_to_cpu(from->sb_rootino);
 366         to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
 367         to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
 368         to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
 369         to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
 370         to->sb_agcount = be32_to_cpu(from->sb_agcount);
 371         to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
 372         to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
 373         to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
 374         to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
 375         to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
 376         to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
 377         memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
 378         to->sb_blocklog = from->sb_blocklog;
 379         to->sb_sectlog = from->sb_sectlog;
 380         to->sb_inodelog = from->sb_inodelog;
 381         to->sb_inopblog = from->sb_inopblog;
 382         to->sb_agblklog = from->sb_agblklog;
 383         to->sb_rextslog = from->sb_rextslog;
 384         to->sb_inprogress = from->sb_inprogress;
 385         to->sb_imax_pct = from->sb_imax_pct;
 386         to->sb_icount = be64_to_cpu(from->sb_icount);
 387         to->sb_ifree = be64_to_cpu(from->sb_ifree);
 388         to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
 389         to->sb_frextents = be64_to_cpu(from->sb_frextents);
 390         to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
 391         to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
 392         to->sb_qflags = be16_to_cpu(from->sb_qflags);
 393         to->sb_flags = from->sb_flags;
 394         to->sb_shared_vn = from->sb_shared_vn;
 395         to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
 396         to->sb_unit = be32_to_cpu(from->sb_unit);
 397         to->sb_width = be32_to_cpu(from->sb_width);
 398         to->sb_dirblklog = from->sb_dirblklog;
 399         to->sb_logsectlog = from->sb_logsectlog;
 400         to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
 401         to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
 402         to->sb_features2 = be32_to_cpu(from->sb_features2);
 403         to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
 404         to->sb_features_compat = be32_to_cpu(from->sb_features_compat);
 405         to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat);
 406         to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat);
 407         to->sb_features_log_incompat =
 408                                 be32_to_cpu(from->sb_features_log_incompat);
 409         /* crc is only used on disk, not in memory; just init to 0 here. */
 410         to->sb_crc = 0;
 411         to->sb_spino_align = be32_to_cpu(from->sb_spino_align);
 412         to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
 413         to->sb_lsn = be64_to_cpu(from->sb_lsn);
 414         /*
 415          * sb_meta_uuid is only on disk if it differs from sb_uuid and the
 416          * feature flag is set; if not set we keep it only in memory.
 417          */
 418         if (xfs_sb_version_hasmetauuid(to))
 419                 uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid);
 420         else
 421                 uuid_copy(&to->sb_meta_uuid, &from->sb_uuid);
 422         /* Convert on-disk flags to in-memory flags? */
 423         if (convert_xquota)
 424                 xfs_sb_quota_from_disk(to);
 425 }
 426
 427 void
 428 xfs_sb_from_disk(
 429         struct xfs_sb   *to,
 430         xfs_dsb_t       *from)
 431 {
 432         __xfs_sb_from_disk(to, from, true);
 433 }
 434
 435 static void
 436 xfs_sb_quota_to_disk(
 437         struct xfs_dsb  *to,
 438         struct xfs_sb   *from)
 439 {
 440         __uint16_t      qflags = from->sb_qflags;
 441
 442         to->sb_uquotino = cpu_to_be64(from->sb_uquotino);
 443         if (xfs_sb_version_has_pquotino(from)) {
 444                 to->sb_qflags = cpu_to_be16(from->sb_qflags);
 445                 to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
 446                 to->sb_pquotino = cpu_to_be64(from->sb_pquotino);
 447                 return;
 448         }
 449
 450         /*
 451          * The in-core version of sb_qflags do not have XFS_OQUOTA_*
 452          * flags, whereas the on-disk version does.  So, convert incore
 453          * XFS_{PG}QUOTA_* flags to on-disk XFS_OQUOTA_* flags.
 454          */
 455         qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD |
 456                         XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD);
 457
 458         if (from->sb_qflags &
 459                         (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD))
 460                 qflags |= XFS_OQUOTA_ENFD;
 461         if (from->sb_qflags &
 462                         (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))
 463                 qflags |= XFS_OQUOTA_CHKD;
 464         to->sb_qflags = cpu_to_be16(qflags);
 465
 466         /*
 467          * GQUOTINO and PQUOTINO cannot be used together in versions
 468          * of superblock that do not have pquotino. from->sb_flags
 469          * tells us which quota is active and should be copied to
 470          * disk. If neither are active, we should NULL the inode.
 471          *
 472          * In all cases, the separate pquotino must remain 0 because it
 473          * it beyond the "end" of the valid non-pquotino superblock.
 474          */
 475         if (from->sb_qflags & XFS_GQUOTA_ACCT)
 476                 to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
 477         else if (from->sb_qflags & XFS_PQUOTA_ACCT)
 478                 to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
 479         else {
 480                 /*
 481                  * We can't rely on just the fields being logged to tell us
 482                  * that it is safe to write NULLFSINO - we should only do that
 483                  * if quotas are not actually enabled. Hence only write
 484                  * NULLFSINO if both in-core quota inodes are NULL.
 485                  */
 486                 if (from->sb_gquotino == NULLFSINO &&
 487                     from->sb_pquotino == NULLFSINO)
 488                         to->sb_gquotino = cpu_to_be64(NULLFSINO);
 489         }
 490
 491         to->sb_pquotino = 0;
 492 }
 493
 494 void
 495 xfs_sb_to_disk(
 496         struct xfs_dsb  *to,
 497         struct xfs_sb   *from)
 498 {
 499         xfs_sb_quota_to_disk(to, from);
 500
 501         to->sb_magicnum = cpu_to_be32(from->sb_magicnum);
 502         to->sb_blocksize = cpu_to_be32(from->sb_blocksize);
 503         to->sb_dblocks = cpu_to_be64(from->sb_dblocks);
 504         to->sb_rblocks = cpu_to_be64(from->sb_rblocks);
 505         to->sb_rextents = cpu_to_be64(from->sb_rextents);
 506         memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
 507         to->sb_logstart = cpu_to_be64(from->sb_logstart);
 508         to->sb_rootino = cpu_to_be64(from->sb_rootino);
 509         to->sb_rbmino = cpu_to_be64(from->sb_rbmino);
 510         to->sb_rsumino = cpu_to_be64(from->sb_rsumino);
 511         to->sb_rextsize = cpu_to_be32(from->sb_rextsize);
 512         to->sb_agblocks = cpu_to_be32(from->sb_agblocks);
 513         to->sb_agcount = cpu_to_be32(from->sb_agcount);
 514         to->sb_rbmblocks = cpu_to_be32(from->sb_rbmblocks);
 515         to->sb_logblocks = cpu_to_be32(from->sb_logblocks);
 516         to->sb_versionnum = cpu_to_be16(from->sb_versionnum);
 517         to->sb_sectsize = cpu_to_be16(from->sb_sectsize);
 518         to->sb_inodesize = cpu_to_be16(from->sb_inodesize);
 519         to->sb_inopblock = cpu_to_be16(from->sb_inopblock);
 520         memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
 521         to->sb_blocklog = from->sb_blocklog;
 522         to->sb_sectlog = from->sb_sectlog;
 523         to->sb_inodelog = from->sb_inodelog;
 524         to->sb_inopblog = from->sb_inopblog;
 525         to->sb_agblklog = from->sb_agblklog;
 526         to->sb_rextslog = from->sb_rextslog;
 527         to->sb_inprogress = from->sb_inprogress;
 528         to->sb_imax_pct = from->sb_imax_pct;
 529         to->sb_icount = cpu_to_be64(from->sb_icount);
 530         to->sb_ifree = cpu_to_be64(from->sb_ifree);
 531         to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks);
 532         to->sb_frextents = cpu_to_be64(from->sb_frextents);
 533
 534         to->sb_flags = from->sb_flags;
 535         to->sb_shared_vn = from->sb_shared_vn;
 536         to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt);
 537         to->sb_unit = cpu_to_be32(from->sb_unit);
 538         to->sb_width = cpu_to_be32(from->sb_width);
 539         to->sb_dirblklog = from->sb_dirblklog;
 540         to->sb_logsectlog = from->sb_logsectlog;
 541         to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize);
 542         to->sb_logsunit = cpu_to_be32(from->sb_logsunit);
 543
 544         /*
 545          * We need to ensure that bad_features2 always matches features2.
 546          * Hence we enforce that here rather than having to remember to do it
 547          * everywhere else that updates features2.
 548          */
 549         from->sb_bad_features2 = from->sb_features2;
 550         to->sb_features2 = cpu_to_be32(from->sb_features2);
 551         to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2);
 552
 553         if (xfs_sb_version_hascrc(from)) {
 554                 to->sb_features_compat = cpu_to_be32(from->sb_features_compat);
 555                 to->sb_features_ro_compat =
 556                                 cpu_to_be32(from->sb_features_ro_compat);
 557                 to->sb_features_incompat =
 558                                 cpu_to_be32(from->sb_features_incompat);
 559                 to->sb_features_log_incompat =
 560                                 cpu_to_be32(from->sb_features_log_incompat);
 561                 to->sb_spino_align = cpu_to_be32(from->sb_spino_align);
 562                 to->sb_lsn = cpu_to_be64(from->sb_lsn);
 563                 if (xfs_sb_version_hasmetauuid(from))
 564                         uuid_copy(&to->sb_meta_uuid, &from->sb_meta_uuid);
 565         }
 566 }
 567
 568 static int
 569 xfs_sb_verify(
 570         struct xfs_buf  *bp,
 571         bool            check_version)
 572 {
 573         struct xfs_mount *mp = bp->b_target->bt_mount;
 574         struct xfs_sb   sb;
 575
 576         /*
 577          * Use call variant which doesn't convert quota flags from disk
 578          * format, because xfs_mount_validate_sb checks the on-disk flags.
 579          */
 580         __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false);
 581
 582         /*
 583          * Only check the in progress field for the primary superblock as
 584          * mkfs.xfs doesn't clear it from secondary superblocks.
 585          */
 586         return xfs_mount_validate_sb(mp, &sb,
 587                                      bp->b_maps[0].bm_bn == XFS_SB_DADDR,
 588                                      check_version);
 589 }
 590
 591 /*
 592  * If the superblock has the CRC feature bit set or the CRC field is non-null,
 593  * check that the CRC is valid.  We check the CRC field is non-null because a
 594  * single bit error could clear the feature bit and unused parts of the
 595  * superblock are supposed to be zero. Hence a non-null crc field indicates that
 596  * we've potentially lost a feature bit and we should check it anyway.
 597  *
 598  * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the
 599  * last field in V4 secondary superblocks.  So for secondary superblocks,
 600  * we are more forgiving, and ignore CRC failures if the primary doesn't
 601  * indicate that the fs version is V5.
 602  */
 603 static void
 604 xfs_sb_read_verify(
 605         struct xfs_buf  *bp)
 606 {
 607         struct xfs_mount *mp = bp->b_target->bt_mount;
 608         struct xfs_dsb  *dsb = XFS_BUF_TO_SBP(bp);
 609         int             error;
 610
 611         /*
 612          * open code the version check to avoid needing to convert the entire
 613          * superblock from disk order just to check the version number
 614          */
 615         if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) &&
 616             (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) ==
 617                                                 XFS_SB_VERSION_5) ||
 618              dsb->sb_crc != 0)) {
 619
 620                 if (!xfs_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) {
 621                         /* Only fail bad secondaries on a known V5 filesystem */
 622                         if (bp->b_bn == XFS_SB_DADDR ||
 623                             xfs_sb_version_hascrc(&mp->m_sb)) {
 624                                 error = -EFSBADCRC;
 625                                 goto out_error;
 626                         }
 627                 }
 628         }
 629         error = xfs_sb_verify(bp, true);
 630
 631 out_error:
 632         if (error) {
 633                 xfs_buf_ioerror(bp, error);
 634                 if (error == -EFSCORRUPTED || error == -EFSBADCRC)
 635                         xfs_verifier_error(bp);
 636         }
 637 }
 638
 639 /*
 640  * We may be probed for a filesystem match, so we may not want to emit
 641  * messages when the superblock buffer is not actually an XFS superblock.
 642  * If we find an XFS superblock, then run a normal, noisy mount because we are
 643  * really going to mount it and want to know about errors.
 644  */
 645 static void
 646 xfs_sb_quiet_read_verify(
 647         struct xfs_buf  *bp)
 648 {
 649         struct xfs_dsb  *dsb = XFS_BUF_TO_SBP(bp);
 650
 651         if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) {
 652                 /* XFS filesystem, verify noisily! */
 653                 xfs_sb_read_verify(bp);
 654                 return;
 655         }
 656         /* quietly fail */
 657         xfs_buf_ioerror(bp, -EWRONGFS);
 658 }
 659
 660 static void
 661 xfs_sb_write_verify(
 662         struct xfs_buf          *bp)
 663 {
 664         struct xfs_mount        *mp = bp->b_target->bt_mount;
 665         struct xfs_buf_log_item *bip = bp->b_fspriv;
 666         int                     error;
 667
 668         error = xfs_sb_verify(bp, false);
 669         if (error) {
 670                 xfs_buf_ioerror(bp, error);
 671                 xfs_verifier_error(bp);
 672                 return;
 673         }
 674
 675         if (!xfs_sb_version_hascrc(&mp->m_sb))
 676                 return;
 677
 678         if (bip)
 679                 XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
 680
 681         xfs_buf_update_cksum(bp, XFS_SB_CRC_OFF);
 682 }
 683
 684 const struct xfs_buf_ops xfs_sb_buf_ops = {
 685         .name = "xfs_sb",
 686         .verify_read = xfs_sb_read_verify,
 687         .verify_write = xfs_sb_write_verify,
 688 };
 689
 690 const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
 691         .name = "xfs_sb_quiet",
 692         .verify_read = xfs_sb_quiet_read_verify,
 693         .verify_write = xfs_sb_write_verify,
 694 };
 695
 696 /*
 697  * xfs_mount_common
 698  *
 699  * Mount initialization code establishing various mount
 700  * fields from the superblock associated with the given
 701  * mount structure
 702  */
 703 void
 704 xfs_sb_mount_common(
 705         struct xfs_mount *mp,
 706         struct xfs_sb   *sbp)
 707 {
 708         mp->m_agfrotor = mp->m_agirotor = 0;
 709         spin_lock_init(&mp->m_agirotor_lock);
 710         mp->m_maxagi = mp->m_sb.sb_agcount;
 711         mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
 712         mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
 713         mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
 714         mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
 715         mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
 716         mp->m_blockmask = sbp->sb_blocksize - 1;
 717         mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
 718         mp->m_blockwmask = mp->m_blockwsize - 1;
 719
 720         mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1);
 721         mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0);
 722         mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2;
 723         mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2;
 724
 725         mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
 726         mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
 727         mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2;
 728         mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2;
 729
 730         mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1);
 731         mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0);
 732         mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
 733         mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;
 734
 735         mp->m_rmap_mxr[0] = xfs_rmapbt_maxrecs(mp, sbp->sb_blocksize, 1);
 736         mp->m_rmap_mxr[1] = xfs_rmapbt_maxrecs(mp, sbp->sb_blocksize, 0);
 737         mp->m_rmap_mnr[0] = mp->m_rmap_mxr[0] / 2;
 738         mp->m_rmap_mnr[1] = mp->m_rmap_mxr[1] / 2;
 739
 740         mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
 741         mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
 742                                         sbp->sb_inopblock);
 743         mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
 744
 745         if (sbp->sb_spino_align)
 746                 mp->m_ialloc_min_blks = sbp->sb_spino_align;
 747         else
 748                 mp->m_ialloc_min_blks = mp->m_ialloc_blks;
 749         mp->m_alloc_set_aside = xfs_alloc_set_aside(mp);
 750         mp->m_ag_max_usable = xfs_alloc_ag_max_usable(mp);
 751 }
 752
 753 /*
 754  * xfs_initialize_perag_data
 755  *
 756  * Read in each per-ag structure so we can count up the number of
 757  * allocated inodes, free inodes and used filesystem blocks as this
 758  * information is no longer persistent in the superblock. Once we have
 759  * this information, write it into the in-core superblock structure.
 760  */
 761 int
 762 xfs_initialize_perag_data(
 763         struct xfs_mount *mp,
 764         xfs_agnumber_t  agcount)
 765 {
 766         xfs_agnumber_t  index;
 767         xfs_perag_t     *pag;
 768         xfs_sb_t        *sbp = &mp->m_sb;
 769         uint64_t        ifree = 0;
 770         uint64_t        ialloc = 0;
 771         uint64_t        bfree = 0;
 772         uint64_t        bfreelst = 0;
 773         uint64_t        btree = 0;
 774         int             error;
 775
 776         for (index = 0; index < agcount; index++) {
 777                 /*
 778                  * read the agf, then the agi. This gets us
 779                  * all the information we need and populates the
 780                  * per-ag structures for us.
 781                  */
 782                 error = xfs_alloc_pagf_init(mp, NULL, index, 0);
 783                 if (error)
 784                         return error;
 785
 786                 error = xfs_ialloc_pagi_init(mp, NULL, index);
 787                 if (error)
 788                         return error;
 789                 pag = xfs_perag_get(mp, index);
 790                 ifree += pag->pagi_freecount;
 791                 ialloc += pag->pagi_count;
 792                 bfree += pag->pagf_freeblks;
 793                 bfreelst += pag->pagf_flcount;
 794                 btree += pag->pagf_btreeblks;
 795                 xfs_perag_put(pag);
 796         }
 797
 798         /* Overwrite incore superblock counters with just-read data */
 799         spin_lock(&mp->m_sb_lock);
 800         sbp->sb_ifree = ifree;
 801         sbp->sb_icount = ialloc;
 802         sbp->sb_fdblocks = bfree + bfreelst + btree;
 803         spin_unlock(&mp->m_sb_lock);
 804
 805         xfs_reinit_percpu_counters(mp);
 806
 807         return 0;
 808 }
 809
 810 /*
 811  * xfs_log_sb() can be used to copy arbitrary changes to the in-core superblock
 812  * into the superblock buffer to be logged.  It does not provide the higher
 813  * level of locking that is needed to protect the in-core superblock from
 814  * concurrent access.
 815  */
 816 void
 817 xfs_log_sb(
 818         struct xfs_trans        *tp)
 819 {
 820         struct xfs_mount        *mp = tp->t_mountp;
 821         struct xfs_buf          *bp = xfs_trans_getsb(tp, mp, 0);
 822
 823         mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount);
 824         mp->m_sb.sb_ifree = percpu_counter_sum(&mp->m_ifree);
 825         mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks);
 826
 827         xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb);
 828         xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
 829         xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb));
 830 }
 831
 832 /*
 833  * xfs_sync_sb
 834  *
 835  * Sync the superblock to disk.
 836  *
 837  * Note that the caller is responsible for checking the frozen state of the
 838  * filesystem. This procedure uses the non-blocking transaction allocator and
 839  * thus will allow modifications to a frozen fs. This is required because this
 840  * code can be called during the process of freezing where use of the high-level
 841  * allocator would deadlock.
 842  */
 843 int
 844 xfs_sync_sb(
 845         struct xfs_mount        *mp,
 846         bool                    wait)
 847 {
 848         struct xfs_trans        *tp;
 849         int                     error;
 850
 851         error = xfs_trans_alloc(mp, &M_RES(mp)->tr_sb, 0, 0,
 852                         XFS_TRANS_NO_WRITECOUNT, &tp);
 853         if (error)
 854                 return error;
 855
 856         xfs_log_sb(tp);
 857         if (wait)
 858                 xfs_trans_set_sync(tp);
 859         return xfs_trans_commit(tp);
 860 }