linux/fs/xfs/libxfs/xfs_sb.c
<<
>>
Prefs
   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_inode.h"
  28#include "xfs_ialloc.h"
  29#include "xfs_alloc.h"
  30#include "xfs_error.h"
  31#include "xfs_trace.h"
  32#include "xfs_cksum.h"
  33#include "xfs_trans.h"
  34#include "xfs_buf_item.h"
  35#include "xfs_bmap_btree.h"
  36#include "xfs_alloc_btree.h"
  37#include "xfs_ialloc_btree.h"
  38
  39/*
  40 * Physical superblock buffer manipulations. Shared with libxfs in userspace.
  41 */
  42
  43static const struct {
  44        short offset;
  45        short type;     /* 0 = integer
  46                         * 1 = binary / string (no translation)
  47                         */
  48} xfs_sb_info[] = {
  49        { offsetof(xfs_sb_t, sb_magicnum),      0 },
  50        { offsetof(xfs_sb_t, sb_blocksize),     0 },
  51        { offsetof(xfs_sb_t, sb_dblocks),       0 },
  52        { offsetof(xfs_sb_t, sb_rblocks),       0 },
  53        { offsetof(xfs_sb_t, sb_rextents),      0 },
  54        { offsetof(xfs_sb_t, sb_uuid),          1 },
  55        { offsetof(xfs_sb_t, sb_logstart),      0 },
  56        { offsetof(xfs_sb_t, sb_rootino),       0 },
  57        { offsetof(xfs_sb_t, sb_rbmino),        0 },
  58        { offsetof(xfs_sb_t, sb_rsumino),       0 },
  59        { offsetof(xfs_sb_t, sb_rextsize),      0 },
  60        { offsetof(xfs_sb_t, sb_agblocks),      0 },
  61        { offsetof(xfs_sb_t, sb_agcount),       0 },
  62        { offsetof(xfs_sb_t, sb_rbmblocks),     0 },
  63        { offsetof(xfs_sb_t, sb_logblocks),     0 },
  64        { offsetof(xfs_sb_t, sb_versionnum),    0 },
  65        { offsetof(xfs_sb_t, sb_sectsize),      0 },
  66        { offsetof(xfs_sb_t, sb_inodesize),     0 },
  67        { offsetof(xfs_sb_t, sb_inopblock),     0 },
  68        { offsetof(xfs_sb_t, sb_fname[0]),      1 },
  69        { offsetof(xfs_sb_t, sb_blocklog),      0 },
  70        { offsetof(xfs_sb_t, sb_sectlog),       0 },
  71        { offsetof(xfs_sb_t, sb_inodelog),      0 },
  72        { offsetof(xfs_sb_t, sb_inopblog),      0 },
  73        { offsetof(xfs_sb_t, sb_agblklog),      0 },
  74        { offsetof(xfs_sb_t, sb_rextslog),      0 },
  75        { offsetof(xfs_sb_t, sb_inprogress),    0 },
  76        { offsetof(xfs_sb_t, sb_imax_pct),      0 },
  77        { offsetof(xfs_sb_t, sb_icount),        0 },
  78        { offsetof(xfs_sb_t, sb_ifree),         0 },
  79        { offsetof(xfs_sb_t, sb_fdblocks),      0 },
  80        { offsetof(xfs_sb_t, sb_frextents),     0 },
  81        { offsetof(xfs_sb_t, sb_uquotino),      0 },
  82        { offsetof(xfs_sb_t, sb_gquotino),      0 },
  83        { offsetof(xfs_sb_t, sb_qflags),        0 },
  84        { offsetof(xfs_sb_t, sb_flags),         0 },
  85        { offsetof(xfs_sb_t, sb_shared_vn),     0 },
  86        { offsetof(xfs_sb_t, sb_inoalignmt),    0 },
  87        { offsetof(xfs_sb_t, sb_unit),          0 },
  88        { offsetof(xfs_sb_t, sb_width),         0 },
  89        { offsetof(xfs_sb_t, sb_dirblklog),     0 },
  90        { offsetof(xfs_sb_t, sb_logsectlog),    0 },
  91        { offsetof(xfs_sb_t, sb_logsectsize),   0 },
  92        { offsetof(xfs_sb_t, sb_logsunit),      0 },
  93        { offsetof(xfs_sb_t, sb_features2),     0 },
  94        { offsetof(xfs_sb_t, sb_bad_features2), 0 },
  95        { offsetof(xfs_sb_t, sb_features_compat),       0 },
  96        { offsetof(xfs_sb_t, sb_features_ro_compat),    0 },
  97        { offsetof(xfs_sb_t, sb_features_incompat),     0 },
  98        { offsetof(xfs_sb_t, sb_features_log_incompat), 0 },
  99        { offsetof(xfs_sb_t, sb_crc),           0 },
 100        { offsetof(xfs_sb_t, sb_pad),           0 },
 101        { offsetof(xfs_sb_t, sb_pquotino),      0 },
 102        { offsetof(xfs_sb_t, sb_lsn),           0 },
 103        { sizeof(xfs_sb_t),                     0 }
 104};
 105
 106/*
 107 * Reference counting access wrappers to the perag structures.
 108 * Because we never free per-ag structures, the only thing we
 109 * have to protect against changes is the tree structure itself.
 110 */
 111struct xfs_perag *
 112xfs_perag_get(
 113        struct xfs_mount        *mp,
 114        xfs_agnumber_t          agno)
 115{
 116        struct xfs_perag        *pag;
 117        int                     ref = 0;
 118
 119        rcu_read_lock();
 120        pag = radix_tree_lookup(&mp->m_perag_tree, agno);
 121        if (pag) {
 122                ASSERT(atomic_read(&pag->pag_ref) >= 0);
 123                ref = atomic_inc_return(&pag->pag_ref);
 124        }
 125        rcu_read_unlock();
 126        trace_xfs_perag_get(mp, agno, ref, _RET_IP_);
 127        return pag;
 128}
 129
 130/*
 131 * search from @first to find the next perag with the given tag set.
 132 */
 133struct xfs_perag *
 134xfs_perag_get_tag(
 135        struct xfs_mount        *mp,
 136        xfs_agnumber_t          first,
 137        int                     tag)
 138{
 139        struct xfs_perag        *pag;
 140        int                     found;
 141        int                     ref;
 142
 143        rcu_read_lock();
 144        found = radix_tree_gang_lookup_tag(&mp->m_perag_tree,
 145                                        (void **)&pag, first, 1, tag);
 146        if (found <= 0) {
 147                rcu_read_unlock();
 148                return NULL;
 149        }
 150        ref = atomic_inc_return(&pag->pag_ref);
 151        rcu_read_unlock();
 152        trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_);
 153        return pag;
 154}
 155
 156void
 157xfs_perag_put(
 158        struct xfs_perag        *pag)
 159{
 160        int     ref;
 161
 162        ASSERT(atomic_read(&pag->pag_ref) > 0);
 163        ref = atomic_dec_return(&pag->pag_ref);
 164        trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_);
 165}
 166
 167/*
 168 * Check the validity of the SB found.
 169 */
 170STATIC int
 171xfs_mount_validate_sb(
 172        xfs_mount_t     *mp,
 173        xfs_sb_t        *sbp,
 174        bool            check_inprogress,
 175        bool            check_version)
 176{
 177
 178        /*
 179         * If the log device and data device have the
 180         * same device number, the log is internal.
 181         * Consequently, the sb_logstart should be non-zero.  If
 182         * we have a zero sb_logstart in this case, we may be trying to mount
 183         * a volume filesystem in a non-volume manner.
 184         */
 185        if (sbp->sb_magicnum != XFS_SB_MAGIC) {
 186                xfs_warn(mp, "bad magic number");
 187                return -EWRONGFS;
 188        }
 189
 190
 191        if (!xfs_sb_good_version(sbp)) {
 192                xfs_warn(mp, "bad version");
 193                return -EWRONGFS;
 194        }
 195
 196        /*
 197         * Version 5 superblock feature mask validation. Reject combinations the
 198         * kernel cannot support up front before checking anything else. For
 199         * write validation, we don't need to check feature masks.
 200         */
 201        if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) {
 202                if (xfs_sb_has_compat_feature(sbp,
 203                                        XFS_SB_FEAT_COMPAT_UNKNOWN)) {
 204                        xfs_warn(mp,
 205"Superblock has unknown compatible features (0x%x) enabled.\n"
 206"Using a more recent kernel is recommended.",
 207                                (sbp->sb_features_compat &
 208                                                XFS_SB_FEAT_COMPAT_UNKNOWN));
 209                }
 210
 211                if (xfs_sb_has_ro_compat_feature(sbp,
 212                                        XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
 213                        xfs_alert(mp,
 214"Superblock has unknown read-only compatible features (0x%x) enabled.",
 215                                (sbp->sb_features_ro_compat &
 216                                                XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
 217                        if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
 218                                xfs_warn(mp,
 219"Attempted to mount read-only compatible filesystem read-write.\n"
 220"Filesystem can only be safely mounted read only.");
 221                                return -EINVAL;
 222                        }
 223                }
 224                if (xfs_sb_has_incompat_feature(sbp,
 225                                        XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
 226                        xfs_warn(mp,
 227"Superblock has unknown incompatible features (0x%x) enabled.\n"
 228"Filesystem can not be safely mounted by this kernel.",
 229                                (sbp->sb_features_incompat &
 230                                                XFS_SB_FEAT_INCOMPAT_UNKNOWN));
 231                        return -EINVAL;
 232                }
 233        }
 234
 235        if (xfs_sb_version_has_pquotino(sbp)) {
 236                if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) {
 237                        xfs_notice(mp,
 238                           "Version 5 of Super block has XFS_OQUOTA bits.");
 239                        return -EFSCORRUPTED;
 240                }
 241        } else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
 242                                XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) {
 243                        xfs_notice(mp,
 244"Superblock earlier than Version 5 has XFS_[PQ]UOTA_{ENFD|CHKD} bits.");
 245                        return -EFSCORRUPTED;
 246        }
 247
 248        if (unlikely(
 249            sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
 250                xfs_warn(mp,
 251                "filesystem is marked as having an external log; "
 252                "specify logdev on the mount command line.");
 253                return -EINVAL;
 254        }
 255
 256        if (unlikely(
 257            sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
 258                xfs_warn(mp,
 259                "filesystem is marked as having an internal log; "
 260                "do not specify logdev on the mount command line.");
 261                return -EINVAL;
 262        }
 263
 264        /*
 265         * More sanity checking.  Most of these were stolen directly from
 266         * xfs_repair.
 267         */
 268        if (unlikely(
 269            sbp->sb_agcount <= 0                                        ||
 270            sbp->sb_sectsize < XFS_MIN_SECTORSIZE                       ||
 271            sbp->sb_sectsize > XFS_MAX_SECTORSIZE                       ||
 272            sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG                    ||
 273            sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG                    ||
 274            sbp->sb_sectsize != (1 << sbp->sb_sectlog)                  ||
 275            sbp->sb_blocksize < XFS_MIN_BLOCKSIZE                       ||
 276            sbp->sb_blocksize > XFS_MAX_BLOCKSIZE                       ||
 277            sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG                    ||
 278            sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG                    ||
 279            sbp->sb_blocksize != (1 << sbp->sb_blocklog)                ||
 280            sbp->sb_dirblklog > XFS_MAX_BLOCKSIZE_LOG                   ||
 281            sbp->sb_inodesize < XFS_DINODE_MIN_SIZE                     ||
 282            sbp->sb_inodesize > XFS_DINODE_MAX_SIZE                     ||
 283            sbp->sb_inodelog < XFS_DINODE_MIN_LOG                       ||
 284            sbp->sb_inodelog > XFS_DINODE_MAX_LOG                       ||
 285            sbp->sb_inodesize != (1 << sbp->sb_inodelog)                ||
 286            sbp->sb_logsunit > XLOG_MAX_RECORD_BSIZE                    ||
 287            sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) ||
 288            (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog)   ||
 289            (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE)  ||
 290            (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE)  ||
 291            (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */)    ||
 292            sbp->sb_dblocks == 0                                        ||
 293            sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp)                      ||
 294            sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp)                      ||
 295            sbp->sb_shared_vn != 0)) {
 296                xfs_notice(mp, "SB sanity check failed");
 297                return -EFSCORRUPTED;
 298        }
 299
 300        /*
 301         * Until this is fixed only page-sized or smaller data blocks work.
 302         */
 303        if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
 304                xfs_warn(mp,
 305                "File system with blocksize %d bytes. "
 306                "Only pagesize (%ld) or less will currently work.",
 307                                sbp->sb_blocksize, PAGE_SIZE);
 308                return -ENOSYS;
 309        }
 310
 311        /*
 312         * Currently only very few inode sizes are supported.
 313         */
 314        switch (sbp->sb_inodesize) {
 315        case 256:
 316        case 512:
 317        case 1024:
 318        case 2048:
 319                break;
 320        default:
 321                xfs_warn(mp, "inode size of %d bytes not supported",
 322                                sbp->sb_inodesize);
 323                return -ENOSYS;
 324        }
 325
 326        if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
 327            xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
 328                xfs_warn(mp,
 329                "file system too large to be mounted on this system.");
 330                return -EFBIG;
 331        }
 332
 333        if (check_inprogress && sbp->sb_inprogress) {
 334                xfs_warn(mp, "Offline file system operation in progress!");
 335                return -EFSCORRUPTED;
 336        }
 337        return 0;
 338}
 339
 340void
 341xfs_sb_quota_from_disk(struct xfs_sb *sbp)
 342{
 343        /*
 344         * older mkfs doesn't initialize quota inodes to NULLFSINO. This
 345         * leads to in-core values having two different values for a quota
 346         * inode to be invalid: 0 and NULLFSINO. Change it to a single value
 347         * NULLFSINO.
 348         *
 349         * Note that this change affect only the in-core values. These
 350         * values are not written back to disk unless any quota information
 351         * is written to the disk. Even in that case, sb_pquotino field is
 352         * not written to disk unless the superblock supports pquotino.
 353         */
 354        if (sbp->sb_uquotino == 0)
 355                sbp->sb_uquotino = NULLFSINO;
 356        if (sbp->sb_gquotino == 0)
 357                sbp->sb_gquotino = NULLFSINO;
 358        if (sbp->sb_pquotino == 0)
 359                sbp->sb_pquotino = NULLFSINO;
 360
 361        /*
 362         * We need to do these manipilations only if we are working
 363         * with an older version of on-disk superblock.
 364         */
 365        if (xfs_sb_version_has_pquotino(sbp))
 366                return;
 367
 368        if (sbp->sb_qflags & XFS_OQUOTA_ENFD)
 369                sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
 370                                        XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD;
 371        if (sbp->sb_qflags & XFS_OQUOTA_CHKD)
 372                sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
 373                                        XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD;
 374        sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD);
 375
 376        if (sbp->sb_qflags & XFS_PQUOTA_ACCT)  {
 377                /*
 378                 * In older version of superblock, on-disk superblock only
 379                 * has sb_gquotino, and in-core superblock has both sb_gquotino
 380                 * and sb_pquotino. But, only one of them is supported at any
 381                 * point of time. So, if PQUOTA is set in disk superblock,
 382                 * copy over sb_gquotino to sb_pquotino.
 383                 */
 384                sbp->sb_pquotino = sbp->sb_gquotino;
 385                sbp->sb_gquotino = NULLFSINO;
 386        }
 387}
 388
 389static void
 390__xfs_sb_from_disk(
 391        struct xfs_sb   *to,
 392        xfs_dsb_t       *from,
 393        bool            convert_xquota)
 394{
 395        to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
 396        to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
 397        to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
 398        to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
 399        to->sb_rextents = be64_to_cpu(from->sb_rextents);
 400        memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
 401        to->sb_logstart = be64_to_cpu(from->sb_logstart);
 402        to->sb_rootino = be64_to_cpu(from->sb_rootino);
 403        to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
 404        to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
 405        to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
 406        to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
 407        to->sb_agcount = be32_to_cpu(from->sb_agcount);
 408        to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
 409        to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
 410        to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
 411        to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
 412        to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
 413        to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
 414        memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
 415        to->sb_blocklog = from->sb_blocklog;
 416        to->sb_sectlog = from->sb_sectlog;
 417        to->sb_inodelog = from->sb_inodelog;
 418        to->sb_inopblog = from->sb_inopblog;
 419        to->sb_agblklog = from->sb_agblklog;
 420        to->sb_rextslog = from->sb_rextslog;
 421        to->sb_inprogress = from->sb_inprogress;
 422        to->sb_imax_pct = from->sb_imax_pct;
 423        to->sb_icount = be64_to_cpu(from->sb_icount);
 424        to->sb_ifree = be64_to_cpu(from->sb_ifree);
 425        to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
 426        to->sb_frextents = be64_to_cpu(from->sb_frextents);
 427        to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
 428        to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
 429        to->sb_qflags = be16_to_cpu(from->sb_qflags);
 430        to->sb_flags = from->sb_flags;
 431        to->sb_shared_vn = from->sb_shared_vn;
 432        to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
 433        to->sb_unit = be32_to_cpu(from->sb_unit);
 434        to->sb_width = be32_to_cpu(from->sb_width);
 435        to->sb_dirblklog = from->sb_dirblklog;
 436        to->sb_logsectlog = from->sb_logsectlog;
 437        to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
 438        to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
 439        to->sb_features2 = be32_to_cpu(from->sb_features2);
 440        to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
 441        to->sb_features_compat = be32_to_cpu(from->sb_features_compat);
 442        to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat);
 443        to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat);
 444        to->sb_features_log_incompat =
 445                                be32_to_cpu(from->sb_features_log_incompat);
 446        /* crc is only used on disk, not in memory; just init to 0 here. */
 447        to->sb_crc = 0;
 448        to->sb_pad = 0;
 449        to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
 450        to->sb_lsn = be64_to_cpu(from->sb_lsn);
 451        /* Convert on-disk flags to in-memory flags? */
 452        if (convert_xquota)
 453                xfs_sb_quota_from_disk(to);
 454}
 455
 456void
 457xfs_sb_from_disk(
 458        struct xfs_sb   *to,
 459        xfs_dsb_t       *from)
 460{
 461        __xfs_sb_from_disk(to, from, true);
 462}
 463
 464static inline void
 465xfs_sb_quota_to_disk(
 466        xfs_dsb_t       *to,
 467        xfs_sb_t        *from,
 468        __int64_t       *fields)
 469{
 470        __uint16_t      qflags = from->sb_qflags;
 471
 472        /*
 473         * We need to do these manipilations only if we are working
 474         * with an older version of on-disk superblock.
 475         */
 476        if (xfs_sb_version_has_pquotino(from))
 477                return;
 478
 479        if (*fields & XFS_SB_QFLAGS) {
 480                /*
 481                 * The in-core version of sb_qflags do not have
 482                 * XFS_OQUOTA_* flags, whereas the on-disk version
 483                 * does.  So, convert incore XFS_{PG}QUOTA_* flags
 484                 * to on-disk XFS_OQUOTA_* flags.
 485                 */
 486                qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD |
 487                                XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD);
 488
 489                if (from->sb_qflags &
 490                                (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD))
 491                        qflags |= XFS_OQUOTA_ENFD;
 492                if (from->sb_qflags &
 493                                (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))
 494                        qflags |= XFS_OQUOTA_CHKD;
 495                to->sb_qflags = cpu_to_be16(qflags);
 496                *fields &= ~XFS_SB_QFLAGS;
 497        }
 498
 499        /*
 500         * GQUOTINO and PQUOTINO cannot be used together in versions of
 501         * superblock that do not have pquotino. from->sb_flags tells us which
 502         * quota is active and should be copied to disk. If neither are active,
 503         * make sure we write NULLFSINO to the sb_gquotino field as a quota
 504         * inode value of "0" is invalid when the XFS_SB_VERSION_QUOTA feature
 505         * bit is set.
 506         *
 507         * Note that we don't need to handle the sb_uquotino or sb_pquotino here
 508         * as they do not require any translation. Hence the main sb field loop
 509         * will write them appropriately from the in-core superblock.
 510         */
 511        if ((*fields & XFS_SB_GQUOTINO) &&
 512                                (from->sb_qflags & XFS_GQUOTA_ACCT))
 513                to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
 514        else if ((*fields & XFS_SB_PQUOTINO) &&
 515                                (from->sb_qflags & XFS_PQUOTA_ACCT))
 516                to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
 517        else {
 518                /*
 519                 * We can't rely on just the fields being logged to tell us
 520                 * that it is safe to write NULLFSINO - we should only do that
 521                 * if quotas are not actually enabled. Hence only write
 522                 * NULLFSINO if both in-core quota inodes are NULL.
 523                 */
 524                if (from->sb_gquotino == NULLFSINO &&
 525                    from->sb_pquotino == NULLFSINO)
 526                        to->sb_gquotino = cpu_to_be64(NULLFSINO);
 527        }
 528
 529        *fields &= ~(XFS_SB_PQUOTINO | XFS_SB_GQUOTINO);
 530}
 531
 532/*
 533 * Copy in core superblock to ondisk one.
 534 *
 535 * The fields argument is mask of superblock fields to copy.
 536 */
 537void
 538xfs_sb_to_disk(
 539        xfs_dsb_t       *to,
 540        xfs_sb_t        *from,
 541        __int64_t       fields)
 542{
 543        xfs_caddr_t     to_ptr = (xfs_caddr_t)to;
 544        xfs_caddr_t     from_ptr = (xfs_caddr_t)from;
 545        xfs_sb_field_t  f;
 546        int             first;
 547        int             size;
 548
 549        ASSERT(fields);
 550        if (!fields)
 551                return;
 552
 553        /* We should never write the crc here, it's updated in the IO path */
 554        fields &= ~XFS_SB_CRC;
 555
 556        xfs_sb_quota_to_disk(to, from, &fields);
 557        while (fields) {
 558                f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
 559                first = xfs_sb_info[f].offset;
 560                size = xfs_sb_info[f + 1].offset - first;
 561
 562                ASSERT(xfs_sb_info[f].type == 0 || xfs_sb_info[f].type == 1);
 563
 564                if (size == 1 || xfs_sb_info[f].type == 1) {
 565                        memcpy(to_ptr + first, from_ptr + first, size);
 566                } else {
 567                        switch (size) {
 568                        case 2:
 569                                *(__be16 *)(to_ptr + first) =
 570                                      cpu_to_be16(*(__u16 *)(from_ptr + first));
 571                                break;
 572                        case 4:
 573                                *(__be32 *)(to_ptr + first) =
 574                                      cpu_to_be32(*(__u32 *)(from_ptr + first));
 575                                break;
 576                        case 8:
 577                                *(__be64 *)(to_ptr + first) =
 578                                      cpu_to_be64(*(__u64 *)(from_ptr + first));
 579                                break;
 580                        default:
 581                                ASSERT(0);
 582                        }
 583                }
 584
 585                fields &= ~(1LL << f);
 586        }
 587}
 588
 589static int
 590xfs_sb_verify(
 591        struct xfs_buf  *bp,
 592        bool            check_version)
 593{
 594        struct xfs_mount *mp = bp->b_target->bt_mount;
 595        struct xfs_sb   sb;
 596
 597        /*
 598         * Use call variant which doesn't convert quota flags from disk 
 599         * format, because xfs_mount_validate_sb checks the on-disk flags.
 600         */
 601        __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false);
 602
 603        /*
 604         * Only check the in progress field for the primary superblock as
 605         * mkfs.xfs doesn't clear it from secondary superblocks.
 606         */
 607        return xfs_mount_validate_sb(mp, &sb, bp->b_bn == XFS_SB_DADDR,
 608                                     check_version);
 609}
 610
 611/*
 612 * If the superblock has the CRC feature bit set or the CRC field is non-null,
 613 * check that the CRC is valid.  We check the CRC field is non-null because a
 614 * single bit error could clear the feature bit and unused parts of the
 615 * superblock are supposed to be zero. Hence a non-null crc field indicates that
 616 * we've potentially lost a feature bit and we should check it anyway.
 617 *
 618 * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the
 619 * last field in V4 secondary superblocks.  So for secondary superblocks,
 620 * we are more forgiving, and ignore CRC failures if the primary doesn't
 621 * indicate that the fs version is V5.
 622 */
 623static void
 624xfs_sb_read_verify(
 625        struct xfs_buf  *bp)
 626{
 627        struct xfs_mount *mp = bp->b_target->bt_mount;
 628        struct xfs_dsb  *dsb = XFS_BUF_TO_SBP(bp);
 629        int             error;
 630
 631        /*
 632         * open code the version check to avoid needing to convert the entire
 633         * superblock from disk order just to check the version number
 634         */
 635        if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) &&
 636            (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) ==
 637                                                XFS_SB_VERSION_5) ||
 638             dsb->sb_crc != 0)) {
 639
 640                if (!xfs_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) {
 641                        /* Only fail bad secondaries on a known V5 filesystem */
 642                        if (bp->b_bn == XFS_SB_DADDR ||
 643                            xfs_sb_version_hascrc(&mp->m_sb)) {
 644                                error = -EFSBADCRC;
 645                                goto out_error;
 646                        }
 647                }
 648        }
 649        error = xfs_sb_verify(bp, true);
 650
 651out_error:
 652        if (error) {
 653                xfs_buf_ioerror(bp, error);
 654                if (error == -EFSCORRUPTED || error == -EFSBADCRC)
 655                        xfs_verifier_error(bp);
 656        }
 657}
 658
 659/*
 660 * We may be probed for a filesystem match, so we may not want to emit
 661 * messages when the superblock buffer is not actually an XFS superblock.
 662 * If we find an XFS superblock, then run a normal, noisy mount because we are
 663 * really going to mount it and want to know about errors.
 664 */
 665static void
 666xfs_sb_quiet_read_verify(
 667        struct xfs_buf  *bp)
 668{
 669        struct xfs_dsb  *dsb = XFS_BUF_TO_SBP(bp);
 670
 671        if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) {
 672                /* XFS filesystem, verify noisily! */
 673                xfs_sb_read_verify(bp);
 674                return;
 675        }
 676        /* quietly fail */
 677        xfs_buf_ioerror(bp, -EWRONGFS);
 678}
 679
 680static void
 681xfs_sb_write_verify(
 682        struct xfs_buf          *bp)
 683{
 684        struct xfs_mount        *mp = bp->b_target->bt_mount;
 685        struct xfs_buf_log_item *bip = bp->b_fspriv;
 686        int                     error;
 687
 688        error = xfs_sb_verify(bp, false);
 689        if (error) {
 690                xfs_buf_ioerror(bp, error);
 691                xfs_verifier_error(bp);
 692                return;
 693        }
 694
 695        if (!xfs_sb_version_hascrc(&mp->m_sb))
 696                return;
 697
 698        if (bip)
 699                XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
 700
 701        xfs_buf_update_cksum(bp, XFS_SB_CRC_OFF);
 702}
 703
 704const struct xfs_buf_ops xfs_sb_buf_ops = {
 705        .verify_read = xfs_sb_read_verify,
 706        .verify_write = xfs_sb_write_verify,
 707};
 708
 709const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
 710        .verify_read = xfs_sb_quiet_read_verify,
 711        .verify_write = xfs_sb_write_verify,
 712};
 713
 714/*
 715 * xfs_mount_common
 716 *
 717 * Mount initialization code establishing various mount
 718 * fields from the superblock associated with the given
 719 * mount structure
 720 */
 721void
 722xfs_sb_mount_common(
 723        struct xfs_mount *mp,
 724        struct xfs_sb   *sbp)
 725{
 726        mp->m_agfrotor = mp->m_agirotor = 0;
 727        spin_lock_init(&mp->m_agirotor_lock);
 728        mp->m_maxagi = mp->m_sb.sb_agcount;
 729        mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
 730        mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
 731        mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
 732        mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
 733        mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
 734        mp->m_blockmask = sbp->sb_blocksize - 1;
 735        mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
 736        mp->m_blockwmask = mp->m_blockwsize - 1;
 737
 738        mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1);
 739        mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0);
 740        mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2;
 741        mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2;
 742
 743        mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
 744        mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
 745        mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2;
 746        mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2;
 747
 748        mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1);
 749        mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0);
 750        mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
 751        mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;
 752
 753        mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
 754        mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
 755                                        sbp->sb_inopblock);
 756        mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
 757}
 758
 759/*
 760 * xfs_initialize_perag_data
 761 *
 762 * Read in each per-ag structure so we can count up the number of
 763 * allocated inodes, free inodes and used filesystem blocks as this
 764 * information is no longer persistent in the superblock. Once we have
 765 * this information, write it into the in-core superblock structure.
 766 */
 767int
 768xfs_initialize_perag_data(
 769        struct xfs_mount *mp,
 770        xfs_agnumber_t  agcount)
 771{
 772        xfs_agnumber_t  index;
 773        xfs_perag_t     *pag;
 774        xfs_sb_t        *sbp = &mp->m_sb;
 775        uint64_t        ifree = 0;
 776        uint64_t        ialloc = 0;
 777        uint64_t        bfree = 0;
 778        uint64_t        bfreelst = 0;
 779        uint64_t        btree = 0;
 780        int             error;
 781
 782        for (index = 0; index < agcount; index++) {
 783                /*
 784                 * read the agf, then the agi. This gets us
 785                 * all the information we need and populates the
 786                 * per-ag structures for us.
 787                 */
 788                error = xfs_alloc_pagf_init(mp, NULL, index, 0);
 789                if (error)
 790                        return error;
 791
 792                error = xfs_ialloc_pagi_init(mp, NULL, index);
 793                if (error)
 794                        return error;
 795                pag = xfs_perag_get(mp, index);
 796                ifree += pag->pagi_freecount;
 797                ialloc += pag->pagi_count;
 798                bfree += pag->pagf_freeblks;
 799                bfreelst += pag->pagf_flcount;
 800                btree += pag->pagf_btreeblks;
 801                xfs_perag_put(pag);
 802        }
 803        /*
 804         * Overwrite incore superblock counters with just-read data
 805         */
 806        spin_lock(&mp->m_sb_lock);
 807        sbp->sb_ifree = ifree;
 808        sbp->sb_icount = ialloc;
 809        sbp->sb_fdblocks = bfree + bfreelst + btree;
 810        spin_unlock(&mp->m_sb_lock);
 811
 812        /* Fixup the per-cpu counters as well. */
 813        xfs_icsb_reinit_counters(mp);
 814
 815        return 0;
 816}
 817
 818/*
 819 * xfs_mod_sb() can be used to copy arbitrary changes to the
 820 * in-core superblock into the superblock buffer to be logged.
 821 * It does not provide the higher level of locking that is
 822 * needed to protect the in-core superblock from concurrent
 823 * access.
 824 */
 825void
 826xfs_mod_sb(xfs_trans_t *tp, __int64_t fields)
 827{
 828        xfs_buf_t       *bp;
 829        int             first;
 830        int             last;
 831        xfs_mount_t     *mp;
 832        xfs_sb_field_t  f;
 833
 834        ASSERT(fields);
 835        if (!fields)
 836                return;
 837        mp = tp->t_mountp;
 838        bp = xfs_trans_getsb(tp, mp, 0);
 839        first = sizeof(xfs_sb_t);
 840        last = 0;
 841
 842        /* translate/copy */
 843
 844        xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, fields);
 845
 846        /* find modified range */
 847        f = (xfs_sb_field_t)xfs_highbit64((__uint64_t)fields);
 848        ASSERT((1LL << f) & XFS_SB_MOD_BITS);
 849        last = xfs_sb_info[f + 1].offset - 1;
 850
 851        f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
 852        ASSERT((1LL << f) & XFS_SB_MOD_BITS);
 853        first = xfs_sb_info[f].offset;
 854
 855        xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
 856        xfs_trans_log_buf(tp, bp, first, last);
 857}
 858