[PATCH 20/49] xfs: introduce xfs_sb.c for sharing with libxfs

Dave Chinner
2013-07-19T06:25:56Z

From: Dave Chinner <dchinner@redhat.com>

xfs_mount.c is shared with userspace, but the only functions that
are shared are to do with physical superblock manipulations. This
means that less than 25% of the xfs_mount.c code is actually shared
with userspace. Move all the superblock functions to xfs_sb.c and
share that instead with libxfs.

Note that this will leave all the in-core transaction related
superblock counter modifications in xfs_mount.c as none of that is
shared with userspace. With a few more small changes, xfs_mount.h
won't need to be shared with userspace anymore, either.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
---
fs/xfs/Makefile | 3 +-
fs/xfs/xfs_mount.c | 817 ++++-------------------------------------------------
fs/xfs/xfs_mount.h | 19 +-
fs/xfs/xfs_sb.c | 771 ++++++++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/xfs_sb.h | 20 ++
5 files changed, 848 insertions(+), 782 deletions(-)
create mode 100644 fs/xfs/xfs_sb.c

diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index 20b1d94..fb14461 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -47,6 +47,7 @@ xfs-y += xfs_aops.o \
xfs_iops.o \
xfs_itable.o \
xfs_message.o \
+ xfs_mount.o \
xfs_mru_cache.o \
xfs_rename.o \
xfs_super.o \
@@ -81,7 +82,7 @@ xfs-y += xfs_alloc.o \
xfs_inode_fork.o \
xfs_inode_buf.o \
xfs_log_recover.o \
- xfs_mount.o \
+ xfs_sb.o \
xfs_symlink_remote.o \
xfs_trans_resv.o

diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 5c7272f..c0eafbe 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -61,69 +61,6 @@ STATIC void xfs_icsb_disable_counter(xfs_mount_t *, xfs_sb_field_t);
#define xfs_icsb_balance_counter_locked(mp, a, b) do { } while (0)
#endif

-static const struct {
- short offset;
- short type; /* 0 = integer
- * 1 = binary / string (no translation)
- */
-} xfs_sb_info[] = {
- { offsetof(xfs_sb_t, sb_magicnum), 0 },
- { offsetof(xfs_sb_t, sb_blocksize), 0 },
- { offsetof(xfs_sb_t, sb_dblocks), 0 },
- { offsetof(xfs_sb_t, sb_rblocks), 0 },
- { offsetof(xfs_sb_t, sb_rextents), 0 },
- { offsetof(xfs_sb_t, sb_uuid), 1 },
- { offsetof(xfs_sb_t, sb_logstart), 0 },
- { offsetof(xfs_sb_t, sb_rootino), 0 },
- { offsetof(xfs_sb_t, sb_rbmino), 0 },
- { offsetof(xfs_sb_t, sb_rsumino), 0 },
- { offsetof(xfs_sb_t, sb_rextsize), 0 },
- { offsetof(xfs_sb_t, sb_agblocks), 0 },
- { offsetof(xfs_sb_t, sb_agcount), 0 },
- { offsetof(xfs_sb_t, sb_rbmblocks), 0 },
- { offsetof(xfs_sb_t, sb_logblocks), 0 },
- { offsetof(xfs_sb_t, sb_versionnum), 0 },
- { offsetof(xfs_sb_t, sb_sectsize), 0 },
- { offsetof(xfs_sb_t, sb_inodesize), 0 },
- { offsetof(xfs_sb_t, sb_inopblock), 0 },
- { offsetof(xfs_sb_t, sb_fname[0]), 1 },
- { offsetof(xfs_sb_t, sb_blocklog), 0 },
- { offsetof(xfs_sb_t, sb_sectlog), 0 },
- { offsetof(xfs_sb_t, sb_inodelog), 0 },
- { offsetof(xfs_sb_t, sb_inopblog), 0 },
- { offsetof(xfs_sb_t, sb_agblklog), 0 },
- { offsetof(xfs_sb_t, sb_rextslog), 0 },
- { offsetof(xfs_sb_t, sb_inprogress), 0 },
- { offsetof(xfs_sb_t, sb_imax_pct), 0 },
- { offsetof(xfs_sb_t, sb_icount), 0 },
- { offsetof(xfs_sb_t, sb_ifree), 0 },
- { offsetof(xfs_sb_t, sb_fdblocks), 0 },
- { offsetof(xfs_sb_t, sb_frextents), 0 },
- { offsetof(xfs_sb_t, sb_uquotino), 0 },
- { offsetof(xfs_sb_t, sb_gquotino), 0 },
- { offsetof(xfs_sb_t, sb_qflags), 0 },
- { offsetof(xfs_sb_t, sb_flags), 0 },
- { offsetof(xfs_sb_t, sb_shared_vn), 0 },
- { offsetof(xfs_sb_t, sb_inoalignmt), 0 },
- { offsetof(xfs_sb_t, sb_unit), 0 },
- { offsetof(xfs_sb_t, sb_width), 0 },
- { offsetof(xfs_sb_t, sb_dirblklog), 0 },
- { offsetof(xfs_sb_t, sb_logsectlog), 0 },
- { offsetof(xfs_sb_t, sb_logsectsize),0 },
- { offsetof(xfs_sb_t, sb_logsunit), 0 },
- { offsetof(xfs_sb_t, sb_features2), 0 },
- { offsetof(xfs_sb_t, sb_bad_features2), 0 },
- { offsetof(xfs_sb_t, sb_features_compat), 0 },
- { offsetof(xfs_sb_t, sb_features_ro_compat), 0 },
- { offsetof(xfs_sb_t, sb_features_incompat), 0 },
- { offsetof(xfs_sb_t, sb_features_log_incompat), 0 },
- { offsetof(xfs_sb_t, sb_crc), 0 },
- { offsetof(xfs_sb_t, sb_pad), 0 },
- { offsetof(xfs_sb_t, sb_pquotino), 0 },
- { offsetof(xfs_sb_t, sb_lsn), 0 },
- { sizeof(xfs_sb_t), 0 }
-};
-
static DEFINE_MUTEX(xfs_uuid_table_mutex);
static int xfs_uuid_table_size;
static uuid_t *xfs_uuid_table;
@@ -199,64 +136,6 @@ xfs_uuid_unmount(
}

-/*
- * Reference counting access wrappers to the perag structures.
- * Because we never free per-ag structures, the only thing we
- * have to protect against changes is the tree structure itself.
- */
-struct xfs_perag *
-xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno)
-{
- struct xfs_perag *pag;
- int ref = 0;
-
- rcu_read_lock();
- pag = radix_tree_lookup(&mp->m_perag_tree, agno);
- if (pag) {
- ASSERT(atomic_read(&pag->pag_ref) >= 0);
- ref = atomic_inc_return(&pag->pag_ref);
- }
- rcu_read_unlock();
- trace_xfs_perag_get(mp, agno, ref, _RET_IP_);
- return pag;
-}
-
-/*
- * search from @first to find the next perag with the given tag set.
- */
-struct xfs_perag *
-xfs_perag_get_tag(
- struct xfs_mount *mp,
- xfs_agnumber_t first,
- int tag)
-{
- struct xfs_perag *pag;
- int found;
- int ref;
-
- rcu_read_lock();
- found = radix_tree_gang_lookup_tag(&mp->m_perag_tree,
- (void **)&pag, first, 1, tag);
- if (found <= 0) {
- rcu_read_unlock();
- return NULL;
- }
- ref = atomic_inc_return(&pag->pag_ref);
- rcu_read_unlock();
- trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_);
- return pag;
-}
-
-void
-xfs_perag_put(struct xfs_perag *pag)
-{
- int ref;
-
- ASSERT(atomic_read(&pag->pag_ref) > 0);
- ref = atomic_dec_return(&pag->pag_ref);
- trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_);
-}
-
STATIC void
__xfs_free_perag(
struct rcu_head *head)
@@ -310,180 +189,67 @@ xfs_sb_validate_fsb_count(
}

/*
- * Check the validity of the SB found.
+ * Update alignment values based on mount options and sb values
*/
STATIC int
-xfs_mount_validate_sb(
- xfs_mount_t *mp,
- xfs_sb_t *sbp,
- bool check_inprogress,
- bool check_version)
+xfs_update_alignment(xfs_mount_t *mp)
{
+ struct xfs_sb *sbp = &mp->m_sb;

- /*
- * If the log device and data device have the
- * same device number, the log is internal.
- * Consequently, the sb_logstart should be non-zero. If
- * we have a zero sb_logstart in this case, we may be trying to mount
- * a volume filesystem in a non-volume manner.
- */
- if (sbp->sb_magicnum != XFS_SB_MAGIC) {
- xfs_warn(mp, "bad magic number");
- return XFS_ERROR(EWRONGFS);
- }
-
-
- if (!xfs_sb_good_version(sbp)) {
- xfs_warn(mp, "bad version");
- return XFS_ERROR(EWRONGFS);
- }
-
- if ((sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) &&
- (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
- XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))) {
- xfs_notice(mp,
-"Super block has XFS_OQUOTA bits along with XFS_PQUOTA and/or XFS_GQUOTA bits.\n");
- return XFS_ERROR(EFSCORRUPTED);
- }
-
- /*
- * Version 5 superblock feature mask validation. Reject combinations the
- * kernel cannot support up front before checking anything else. For
- * write validation, we don't need to check feature masks.
- */
- if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) {
- xfs_alert(mp,
-"Version 5 superblock detected. This kernel has EXPERIMENTAL support enabled!\n"
-"Use of these features in this kernel is at your own risk!");
-
- if (xfs_sb_has_compat_feature(sbp,
- XFS_SB_FEAT_COMPAT_UNKNOWN)) {
+ if (mp->m_dalign) {
+ /*
+ * If stripe unit and stripe width are not multiples
+ * of the fs blocksize turn off alignment.
+ */
+ if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
+ (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
xfs_warn(mp,
-"Superblock has unknown compatible features (0x%x) enabled.\n"
-"Using a more recent kernel is recommended.",
- (sbp->sb_features_compat &
- XFS_SB_FEAT_COMPAT_UNKNOWN));
- }
-
- if (xfs_sb_has_ro_compat_feature(sbp,
- XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
- xfs_alert(mp,
-"Superblock has unknown read-only compatible features (0x%x) enabled.",
- (sbp->sb_features_ro_compat &
- XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
- if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
+ "alignment check failed: sunit/swidth vs. blocksize(%d)",
+ sbp->sb_blocksize);
+ return XFS_ERROR(EINVAL);
+ } else {
+ /*
+ * Convert the stripe unit and width to FSBs.
+ */
+ mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
+ if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
xfs_warn(mp,
-"Attempted to mount read-only compatible filesystem read-write.\n"
-"Filesystem can only be safely mounted read only.");
+ "alignment check failed: sunit/swidth vs. agsize(%d)",
+ sbp->sb_agblocks);
+ return XFS_ERROR(EINVAL);
+ } else if (mp->m_dalign) {
+ mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
+ } else {
+ xfs_warn(mp,
+ "alignment check failed: sunit(%d) less than bsize(%d)",
+ mp->m_dalign, sbp->sb_blocksize);
return XFS_ERROR(EINVAL);
}
}
- if (xfs_sb_has_incompat_feature(sbp,
- XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
+
+ /*
+ * Update superblock with new values
+ * and log changes
+ */
+ if (xfs_sb_version_hasdalign(sbp)) {
+ if (sbp->sb_unit != mp->m_dalign) {
+ sbp->sb_unit = mp->m_dalign;
+ mp->m_update_flags |= XFS_SB_UNIT;
+ }
+ if (sbp->sb_width != mp->m_swidth) {
+ sbp->sb_width = mp->m_swidth;
+ mp->m_update_flags |= XFS_SB_WIDTH;
+ }
+ } else {
xfs_warn(mp,
-"Superblock has unknown incompatible features (0x%x) enabled.\n"
-"Filesystem can not be safely mounted by this kernel.",
- (sbp->sb_features_incompat &
- XFS_SB_FEAT_INCOMPAT_UNKNOWN));
+ "cannot change alignment: superblock does not support data alignment");
return XFS_ERROR(EINVAL);
}
+ } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
+ xfs_sb_version_hasdalign(&mp->m_sb)) {
+ mp->m_dalign = sbp->sb_unit;
+ mp->m_swidth = sbp->sb_width;
}
-
- if (unlikely(
- sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
- xfs_warn(mp,
- "filesystem is marked as having an external log; "
- "specify logdev on the mount command line.");
- return XFS_ERROR(EINVAL);
- }
-
- if (unlikely(
- sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
- xfs_warn(mp,
- "filesystem is marked as having an internal log; "
- "do not specify logdev on the mount command line.");
- return XFS_ERROR(EINVAL);
- }
-
- /*
- * More sanity checking. Most of these were stolen directly from
- * xfs_repair.
- */
- if (unlikely(
- sbp->sb_agcount <= 0 ||
- sbp->sb_sectsize < XFS_MIN_SECTORSIZE ||
- sbp->sb_sectsize > XFS_MAX_SECTORSIZE ||
- sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG ||
- sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG ||
- sbp->sb_sectsize != (1 << sbp->sb_sectlog) ||
- sbp->sb_blocksize < XFS_MIN_BLOCKSIZE ||
- sbp->sb_blocksize > XFS_MAX_BLOCKSIZE ||
- sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG ||
- sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG ||
- sbp->sb_blocksize != (1 << sbp->sb_blocklog) ||
- sbp->sb_inodesize < XFS_DINODE_MIN_SIZE ||
- sbp->sb_inodesize > XFS_DINODE_MAX_SIZE ||
- sbp->sb_inodelog < XFS_DINODE_MIN_LOG ||
- sbp->sb_inodelog > XFS_DINODE_MAX_LOG ||
- sbp->sb_inodesize != (1 << sbp->sb_inodelog) ||
- (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) ||
- (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) ||
- (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) ||
- (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) ||
- sbp->sb_dblocks == 0 ||
- sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) ||
- sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp))) {
- XFS_CORRUPTION_ERROR("SB sanity check failed",
- XFS_ERRLEVEL_LOW, mp, sbp);
- return XFS_ERROR(EFSCORRUPTED);
- }
-
- /*
- * Until this is fixed only page-sized or smaller data blocks work.
- */
- if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
- xfs_warn(mp,
- "File system with blocksize %d bytes. "
- "Only pagesize (%ld) or less will currently work.",
- sbp->sb_blocksize, PAGE_SIZE);
- return XFS_ERROR(ENOSYS);
- }
-
- /*
- * Currently only very few inode sizes are supported.
- */
- switch (sbp->sb_inodesize) {
- case 256:
- case 512:
- case 1024:
- case 2048:
- break;
- default:
- xfs_warn(mp, "inode size of %d bytes not supported",
- sbp->sb_inodesize);
- return XFS_ERROR(ENOSYS);
- }
-
- if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
- xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
- xfs_warn(mp,
- "file system too large to be mounted on this system.");
- return XFS_ERROR(EFBIG);
- }
-
- if (check_inprogress && sbp->sb_inprogress) {
- xfs_warn(mp, "Offline file system operation in progress!");
- return XFS_ERROR(EFSCORRUPTED);
- }
-
- /*
- * Version 1 directory format has never worked on Linux.
- */
- if (unlikely(!xfs_sb_version_hasdirv2(sbp))) {
- xfs_warn(mp, "file system using version 1 directory format");
- return XFS_ERROR(ENOSYS);
- }
-
return 0;
}

@@ -571,283 +337,15 @@ out_unwind:
return error;
}

-static void
-xfs_sb_quota_from_disk(struct xfs_sb *sbp)
-{
- if (sbp->sb_qflags & XFS_OQUOTA_ENFD)
- sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
- XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD;
- if (sbp->sb_qflags & XFS_OQUOTA_CHKD)
- sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
- XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD;
- sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD);
-}
-
-void
-xfs_sb_from_disk(
- struct xfs_sb *to,
- xfs_dsb_t *from)
-{
- to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
- to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
- to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
- to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
- to->sb_rextents = be64_to_cpu(from->sb_rextents);
- memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
- to->sb_logstart = be64_to_cpu(from->sb_logstart);
- to->sb_rootino = be64_to_cpu(from->sb_rootino);
- to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
- to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
- to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
- to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
- to->sb_agcount = be32_to_cpu(from->sb_agcount);
- to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
- to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
- to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
- to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
- to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
- to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
- memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
- to->sb_blocklog = from->sb_blocklog;
- to->sb_sectlog = from->sb_sectlog;
- to->sb_inodelog = from->sb_inodelog;
- to->sb_inopblog = from->sb_inopblog;
- to->sb_agblklog = from->sb_agblklog;
- to->sb_rextslog = from->sb_rextslog;
- to->sb_inprogress = from->sb_inprogress;
- to->sb_imax_pct = from->sb_imax_pct;
- to->sb_icount = be64_to_cpu(from->sb_icount);
- to->sb_ifree = be64_to_cpu(from->sb_ifree);
- to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
- to->sb_frextents = be64_to_cpu(from->sb_frextents);
- to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
- to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
- to->sb_qflags = be16_to_cpu(from->sb_qflags);
- to->sb_flags = from->sb_flags;
- to->sb_shared_vn = from->sb_shared_vn;
- to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
- to->sb_unit = be32_to_cpu(from->sb_unit);
- to->sb_width = be32_to_cpu(from->sb_width);
- to->sb_dirblklog = from->sb_dirblklog;
- to->sb_logsectlog = from->sb_logsectlog;
- to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
- to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
- to->sb_features2 = be32_to_cpu(from->sb_features2);
- to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
- to->sb_features_compat = be32_to_cpu(from->sb_features_compat);
- to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat);
- to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat);
- to->sb_features_log_incompat =
- be32_to_cpu(from->sb_features_log_incompat);
- to->sb_pad = 0;
- to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
- to->sb_lsn = be64_to_cpu(from->sb_lsn);
-}
-
-static inline void
-xfs_sb_quota_to_disk(
- xfs_dsb_t *to,
- xfs_sb_t *from,
- __int64_t *fields)
-{
- __uint16_t qflags = from->sb_qflags;
-
- if (*fields & XFS_SB_QFLAGS) {
- /*
- * The in-core version of sb_qflags do not have
- * XFS_OQUOTA_* flags, whereas the on-disk version
- * does. So, convert incore XFS_{PG}QUOTA_* flags
- * to on-disk XFS_OQUOTA_* flags.
- */
- qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD |
- XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD);
-
- if (from->sb_qflags &
- (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD))
- qflags |= XFS_OQUOTA_ENFD;
- if (from->sb_qflags &
- (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))
- qflags |= XFS_OQUOTA_CHKD;
- to->sb_qflags = cpu_to_be16(qflags);
- *fields &= ~XFS_SB_QFLAGS;
- }
-}
-
-/*
- * Copy in core superblock to ondisk one.
- *
- * The fields argument is mask of superblock fields to copy.
- */
-void
-xfs_sb_to_disk(
- xfs_dsb_t *to,
- xfs_sb_t *from,
- __int64_t fields)
-{
- xfs_caddr_t to_ptr = (xfs_caddr_t)to;
- xfs_caddr_t from_ptr = (xfs_caddr_t)from;
- xfs_sb_field_t f;
- int first;
- int size;
-
- ASSERT(fields);
- if (!fields)
- return;
-
- xfs_sb_quota_to_disk(to, from, &fields);
- while (fields) {
- f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
- first = xfs_sb_info[f].offset;
- size = xfs_sb_info[f + 1].offset - first;
-
- ASSERT(xfs_sb_info[f].type == 0 || xfs_sb_info[f].type == 1);
-
- if (size == 1 || xfs_sb_info[f].type == 1) {
- memcpy(to_ptr + first, from_ptr + first, size);
- } else {
- switch (size) {
- case 2:
- *(__be16 *)(to_ptr + first) =
- cpu_to_be16(*(__u16 *)(from_ptr + first));
- break;
- case 4:
- *(__be32 *)(to_ptr + first) =
- cpu_to_be32(*(__u32 *)(from_ptr + first));
- break;
- case 8:
- *(__be64 *)(to_ptr + first) =
- cpu_to_be64(*(__u64 *)(from_ptr + first));
- break;
- default:
- ASSERT(0);
- }
- }
-
- fields &= ~(1LL << f);
- }
-}
-
-static int
-xfs_sb_verify(
- struct xfs_buf *bp,
- bool check_version)
-{
- struct xfs_mount *mp = bp->b_target->bt_mount;
- struct xfs_sb sb;
-
- xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp));
-
- /*
- * Only check the in progress field for the primary superblock as
- * mkfs.xfs doesn't clear it from secondary superblocks.
- */
- return xfs_mount_validate_sb(mp, &sb, bp->b_bn == XFS_SB_DADDR,
- check_version);
-}
-
-/*
- * If the superblock has the CRC feature bit set or the CRC field is non-null,
- * check that the CRC is valid. We check the CRC field is non-null because a
- * single bit error could clear the feature bit and unused parts of the
- * superblock are supposed to be zero. Hence a non-null crc field indicates that
- * we've potentially lost a feature bit and we should check it anyway.
- */
-static void
-xfs_sb_read_verify(
- struct xfs_buf *bp)
-{
- struct xfs_mount *mp = bp->b_target->bt_mount;
- struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp);
- int error;
-
- /*
- * open code the version check to avoid needing to convert the entire
- * superblock from disk order just to check the version number
- */
- if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) &&
- (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) ==
- XFS_SB_VERSION_5) ||
- dsb->sb_crc != 0)) {
-
- if (!xfs_verify_cksum(bp->b_addr, be16_to_cpu(dsb->sb_sectsize),
- offsetof(struct xfs_sb, sb_crc))) {
- error = EFSCORRUPTED;
- goto out_error;
- }
- }
- error = xfs_sb_verify(bp, true);
-
-out_error:
- if (error) {
- XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
- xfs_buf_ioerror(bp, error);
- }
-}
-
-/*
- * We may be probed for a filesystem match, so we may not want to emit
- * messages when the superblock buffer is not actually an XFS superblock.
- * If we find an XFS superblock, the run a normal, noisy mount because we are
- * really going to mount it and want to know about errors.
- */
-static void
-xfs_sb_quiet_read_verify(
- struct xfs_buf *bp)
-{
- struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp);
-
-
- if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) {
- /* XFS filesystem, verify noisily! */
- xfs_sb_read_verify(bp);
- return;
- }
- /* quietly fail */
- xfs_buf_ioerror(bp, EWRONGFS);
-}
-
-static void
-xfs_sb_write_verify(
- struct xfs_buf *bp)
-{
- struct xfs_mount *mp = bp->b_target->bt_mount;
- struct xfs_buf_log_item *bip = bp->b_fspriv;
- int error;
-
- error = xfs_sb_verify(bp, false);
- if (error) {
- XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
- xfs_buf_ioerror(bp, error);
- return;
- }
-
- if (!xfs_sb_version_hascrc(&mp->m_sb))
- return;
-
- if (bip)
- XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
-
- xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
- offsetof(struct xfs_sb, sb_crc));
-}
-
-const struct xfs_buf_ops xfs_sb_buf_ops = {
- .verify_read = xfs_sb_read_verify,
- .verify_write = xfs_sb_write_verify,
-};
-
-static const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
- .verify_read = xfs_sb_quiet_read_verify,
- .verify_write = xfs_sb_write_verify,
-};
-
/*
* xfs_readsb
*
* Does the initial read of the superblock.
*/
int
-xfs_readsb(xfs_mount_t *mp, int flags)
+xfs_readsb(
+ struct xfs_mount *mp,
+ int flags)
{
unsigned int sector_size;
struct xfs_buf *bp;
@@ -886,8 +384,8 @@ reread:
* Initialize the mount structure from the superblock.
*/
xfs_sb_from_disk(&mp->m_sb, XFS_BUF_TO_SBP(bp));
-
xfs_sb_quota_from_disk(&mp->m_sb);
+
/*
* We must be able to do sector-sized and sector-aligned IO.
*/
@@ -924,173 +422,6 @@ release_buf:
return error;
}

-
-/*
- * xfs_mount_common
- *
- * Mount initialization code establishing various mount
- * fields from the superblock associated with the given
- * mount structure
- */
-STATIC void
-xfs_mount_common(xfs_mount_t *mp, xfs_sb_t *sbp)
-{
- mp->m_agfrotor = mp->m_agirotor = 0;
- spin_lock_init(&mp->m_agirotor_lock);
- mp->m_maxagi = mp->m_sb.sb_agcount;
- mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
- mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
- mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
- mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
- mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
- mp->m_blockmask = sbp->sb_blocksize - 1;
- mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
- mp->m_blockwmask = mp->m_blockwsize - 1;
-
- mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1);
- mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0);
- mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2;
- mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2;
-
- mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
- mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
- mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2;
- mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2;
-
- mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1);
- mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0);
- mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
- mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;
-
- mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
- mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
- sbp->sb_inopblock);
- mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
-}
-
-/*
- * xfs_initialize_perag_data
- *
- * Read in each per-ag structure so we can count up the number of
- * allocated inodes, free inodes and used filesystem blocks as this
- * information is no longer persistent in the superblock. Once we have
- * this information, write it into the in-core superblock structure.
- */
-STATIC int
-xfs_initialize_perag_data(xfs_mount_t *mp, xfs_agnumber_t agcount)
-{
- xfs_agnumber_t index;
- xfs_perag_t *pag;
- xfs_sb_t *sbp = &mp->m_sb;
- uint64_t ifree = 0;
- uint64_t ialloc = 0;
- uint64_t bfree = 0;
- uint64_t bfreelst = 0;
- uint64_t btree = 0;
- int error;
-
- for (index = 0; index < agcount; index++) {
- /*
- * read the agf, then the agi. This gets us
- * all the information we need and populates the
- * per-ag structures for us.
- */
- error = xfs_alloc_pagf_init(mp, NULL, index, 0);
- if (error)
- return error;
-
- error = xfs_ialloc_pagi_init(mp, NULL, index);
- if (error)
- return error;
- pag = xfs_perag_get(mp, index);
- ifree += pag->pagi_freecount;
- ialloc += pag->pagi_count;
- bfree += pag->pagf_freeblks;
- bfreelst += pag->pagf_flcount;
- btree += pag->pagf_btreeblks;
- xfs_perag_put(pag);
- }
- /*
- * Overwrite incore superblock counters with just-read data
- */
- spin_lock(&mp->m_sb_lock);
- sbp->sb_ifree = ifree;
- sbp->sb_icount = ialloc;
- sbp->sb_fdblocks = bfree + bfreelst + btree;
- spin_unlock(&mp->m_sb_lock);
-
- /* Fixup the per-cpu counters as well. */
- xfs_icsb_reinit_counters(mp);
-
- return 0;
-}
-
-/*
- * Update alignment values based on mount options and sb values
- */
-STATIC int
-xfs_update_alignment(xfs_mount_t *mp)
-{
- xfs_sb_t *sbp = &(mp->m_sb);
-
- if (mp->m_dalign) {
- /*
- * If stripe unit and stripe width are not multiples
- * of the fs blocksize turn off alignment.
- */
- if ((BBTOB(mp->m_dalign) & mp->m_blockmask) ||
- (BBTOB(mp->m_swidth) & mp->m_blockmask)) {
- xfs_warn(mp,
- "alignment check failed: sunit/swidth vs. blocksize(%d)",
- sbp->sb_blocksize);
- return XFS_ERROR(EINVAL);
- } else {
- /*
- * Convert the stripe unit and width to FSBs.
- */
- mp->m_dalign = XFS_BB_TO_FSBT(mp, mp->m_dalign);
- if (mp->m_dalign && (sbp->sb_agblocks % mp->m_dalign)) {
- xfs_warn(mp,
- "alignment check failed: sunit/swidth vs. agsize(%d)",
- sbp->sb_agblocks);
- return XFS_ERROR(EINVAL);
- } else if (mp->m_dalign) {
- mp->m_swidth = XFS_BB_TO_FSBT(mp, mp->m_swidth);
- } else {
- xfs_warn(mp,
- "alignment check failed: sunit(%d) less than bsize(%d)",
- mp->m_dalign, sbp->sb_blocksize);
- return XFS_ERROR(EINVAL);
- }
- }
-
- /*
- * Update superblock with new values
- * and log changes
- */
- if (xfs_sb_version_hasdalign(sbp)) {
- if (sbp->sb_unit != mp->m_dalign) {
- sbp->sb_unit = mp->m_dalign;
- mp->m_update_flags |= XFS_SB_UNIT;
- }
- if (sbp->sb_width != mp->m_swidth) {
- sbp->sb_width = mp->m_swidth;
- mp->m_update_flags |= XFS_SB_WIDTH;
- }
- } else {
- xfs_warn(mp,
- "cannot change alignment: superblock does not support data alignment");
- return XFS_ERROR(EINVAL);
- }
- } else if ((mp->m_flags & XFS_MOUNT_NOALIGN) != XFS_MOUNT_NOALIGN &&
- xfs_sb_version_hasdalign(&mp->m_sb)) {
- mp->m_dalign = sbp->sb_unit;
- mp->m_swidth = sbp->sb_width;
- }
-
- return 0;
-}
-
/*
* Set the maximum inode count for this filesystem
*/
@@ -1317,7 +648,7 @@ xfs_mountfs(
uint quotaflags = 0;
int error = 0;

- xfs_mount_common(mp, sbp);
+ xfs_sb_mount_common(mp, sbp);

/*
* Check for a mismatched features2 values. Older kernels
@@ -1754,48 +1085,6 @@ xfs_log_sbcount(xfs_mount_t *mp)
}

/*
- * xfs_mod_sb() can be used to copy arbitrary changes to the
- * in-core superblock into the superblock buffer to be logged.
- * It does not provide the higher level of locking that is
- * needed to protect the in-core superblock from concurrent
- * access.
- */
-void
-xfs_mod_sb(xfs_trans_t *tp, __int64_t fields)
-{
- xfs_buf_t *bp;
- int first;
- int last;
- xfs_mount_t *mp;
- xfs_sb_field_t f;
-
- ASSERT(fields);
- if (!fields)
- return;
- mp = tp->t_mountp;
- bp = xfs_trans_getsb(tp, mp, 0);
- first = sizeof(xfs_sb_t);
- last = 0;
-
- /* translate/copy */
-
- xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, fields);
-
- /* find modified range */
- f = (xfs_sb_field_t)xfs_highbit64((__uint64_t)fields);
- ASSERT((1LL << f) & XFS_SB_MOD_BITS);
- last = xfs_sb_info[f + 1].offset - 1;
-
- f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
- ASSERT((1LL << f) & XFS_SB_MOD_BITS);
- first = xfs_sb_info[f].offset;
-
- xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
- xfs_trans_log_buf(tp, bp, first, last);
-}
-
-
-/*
* xfs_mod_incore_sb_unlocked() is a utility routine common used to apply
* a delta to a specified field in the in-core superblock. Simply
* switch on the field indicated and apply the delta to that field.
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 27d0d5c..5488df1 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -292,14 +292,6 @@ xfs_daddr_to_agbno(struct xfs_mount *mp, xfs_daddr_t d)
}

/*
- * perag get/put wrappers for ref counting
- */
-struct xfs_perag *xfs_perag_get(struct xfs_mount *mp, xfs_agnumber_t agno);
-struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *mp, xfs_agnumber_t agno,
- int tag);
-void xfs_perag_put(struct xfs_perag *pag);
-
-/*
* Per-cpu superblock locking functions
*/
#ifdef HAVE_PERCPU_SB
@@ -331,6 +323,8 @@ typedef struct xfs_mod_sb {
extern int xfs_log_sbcount(xfs_mount_t *);
extern __uint64_t xfs_default_resblks(xfs_mount_t *mp);
extern int xfs_mountfs(xfs_mount_t *mp);
+extern int xfs_initialize_perag(xfs_mount_t *mp, xfs_agnumber_t agcount,
+ xfs_agnumber_t *maxagi);

extern void xfs_unmountfs(xfs_mount_t *);
extern int xfs_mod_incore_sb(xfs_mount_t *, xfs_sb_field_t, int64_t, int);
@@ -349,13 +343,4 @@ extern void xfs_set_low_space_thresholds(struct xfs_mount *);

#endif /* __KERNEL__ */

-extern void xfs_sb_calc_crc(struct xfs_buf *);
-extern void xfs_mod_sb(struct xfs_trans *, __int64_t);
-extern int xfs_initialize_perag(struct xfs_mount *, xfs_agnumber_t,
- xfs_agnumber_t *);
-extern void xfs_sb_from_disk(struct xfs_sb *, struct xfs_dsb *);
-extern void xfs_sb_to_disk(struct xfs_dsb *, struct xfs_sb *, __int64_t);
-
-extern const struct xfs_buf_ops xfs_sb_buf_ops;
-
#endif /* __XFS_MOUNT_H__ */
diff --git a/fs/xfs/xfs_sb.c b/fs/xfs/xfs_sb.c
new file mode 100644
index 0000000..e650600
--- /dev/null
+++ b/fs/xfs/xfs_sb.c
@@ -0,0 +1,771 @@
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_format.h"
+#include "xfs_bit.h"
+#include "xfs_log.h"
+#include "xfs_inum.h"
+#include "xfs_trans.h"
+#include "xfs_trans_priv.h"
+#include "xfs_sb.h"
+#include "xfs_ag.h"
+#include "xfs_mount.h"
+#include "xfs_da_btree.h"
+#include "xfs_dir2_format.h"
+#include "xfs_dir2.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_ialloc_btree.h"
+#include "xfs_dinode.h"
+#include "xfs_inode.h"
+#include "xfs_btree.h"
+#include "xfs_ialloc.h"
+#include "xfs_alloc.h"
+#include "xfs_rtalloc.h"
+#include "xfs_bmap.h"
+#include "xfs_error.h"
+#include "xfs_quota.h"
+#include "xfs_fsops.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+#include "xfs_buf_item.h"
+
+/*
+ * Physical superblock buffer manipulations. Shared with libxfs in userspace.
+ */
+
+static const struct {
+ short offset;
+ short type; /* 0 = integer
+ * 1 = binary / string (no translation)
+ */
+} xfs_sb_info[] = {
+ { offsetof(xfs_sb_t, sb_magicnum), 0 },
+ { offsetof(xfs_sb_t, sb_blocksize), 0 },
+ { offsetof(xfs_sb_t, sb_dblocks), 0 },
+ { offsetof(xfs_sb_t, sb_rblocks), 0 },
+ { offsetof(xfs_sb_t, sb_rextents), 0 },
+ { offsetof(xfs_sb_t, sb_uuid), 1 },
+ { offsetof(xfs_sb_t, sb_logstart), 0 },
+ { offsetof(xfs_sb_t, sb_rootino), 0 },
+ { offsetof(xfs_sb_t, sb_rbmino), 0 },
+ { offsetof(xfs_sb_t, sb_rsumino), 0 },
+ { offsetof(xfs_sb_t, sb_rextsize), 0 },
+ { offsetof(xfs_sb_t, sb_agblocks), 0 },
+ { offsetof(xfs_sb_t, sb_agcount), 0 },
+ { offsetof(xfs_sb_t, sb_rbmblocks), 0 },
+ { offsetof(xfs_sb_t, sb_logblocks), 0 },
+ { offsetof(xfs_sb_t, sb_versionnum), 0 },
+ { offsetof(xfs_sb_t, sb_sectsize), 0 },
+ { offsetof(xfs_sb_t, sb_inodesize), 0 },
+ { offsetof(xfs_sb_t, sb_inopblock), 0 },
+ { offsetof(xfs_sb_t, sb_fname[0]), 1 },
+ { offsetof(xfs_sb_t, sb_blocklog), 0 },
+ { offsetof(xfs_sb_t, sb_sectlog), 0 },
+ { offsetof(xfs_sb_t, sb_inodelog), 0 },
+ { offsetof(xfs_sb_t, sb_inopblog), 0 },
+ { offsetof(xfs_sb_t, sb_agblklog), 0 },
+ { offsetof(xfs_sb_t, sb_rextslog), 0 },
+ { offsetof(xfs_sb_t, sb_inprogress), 0 },
+ { offsetof(xfs_sb_t, sb_imax_pct), 0 },
+ { offsetof(xfs_sb_t, sb_icount), 0 },
+ { offsetof(xfs_sb_t, sb_ifree), 0 },
+ { offsetof(xfs_sb_t, sb_fdblocks), 0 },
+ { offsetof(xfs_sb_t, sb_frextents), 0 },
+ { offsetof(xfs_sb_t, sb_uquotino), 0 },
+ { offsetof(xfs_sb_t, sb_gquotino), 0 },
+ { offsetof(xfs_sb_t, sb_qflags), 0 },
+ { offsetof(xfs_sb_t, sb_flags), 0 },
+ { offsetof(xfs_sb_t, sb_shared_vn), 0 },
+ { offsetof(xfs_sb_t, sb_inoalignmt), 0 },
+ { offsetof(xfs_sb_t, sb_unit), 0 },
+ { offsetof(xfs_sb_t, sb_width), 0 },
+ { offsetof(xfs_sb_t, sb_dirblklog), 0 },
+ { offsetof(xfs_sb_t, sb_logsectlog), 0 },
+ { offsetof(xfs_sb_t, sb_logsectsize),0 },
+ { offsetof(xfs_sb_t, sb_logsunit), 0 },
+ { offsetof(xfs_sb_t, sb_features2), 0 },
+ { offsetof(xfs_sb_t, sb_bad_features2), 0 },
+ { offsetof(xfs_sb_t, sb_features_compat), 0 },
+ { offsetof(xfs_sb_t, sb_features_ro_compat), 0 },
+ { offsetof(xfs_sb_t, sb_features_incompat), 0 },
+ { offsetof(xfs_sb_t, sb_features_log_incompat), 0 },
+ { offsetof(xfs_sb_t, sb_crc), 0 },
+ { offsetof(xfs_sb_t, sb_pad), 0 },
+ { offsetof(xfs_sb_t, sb_pquotino), 0 },
+ { offsetof(xfs_sb_t, sb_lsn), 0 },
+ { sizeof(xfs_sb_t), 0 }
+};
+
+/*
+ * Reference counting access wrappers to the perag structures.
+ * Because we never free per-ag structures, the only thing we
+ * have to protect against changes is the tree structure itself.
+ */
+struct xfs_perag *
+xfs_perag_get(
+ struct xfs_mount *mp,
+ xfs_agnumber_t agno)
+{
+ struct xfs_perag *pag;
+ int ref = 0;
+
+ rcu_read_lock();
+ pag = radix_tree_lookup(&mp->m_perag_tree, agno);
+ if (pag) {
+ ASSERT(atomic_read(&pag->pag_ref) >= 0);
+ ref = atomic_inc_return(&pag->pag_ref);
+ }
+ rcu_read_unlock();
+ trace_xfs_perag_get(mp, agno, ref, _RET_IP_);
+ return pag;
+}
+
+/*
+ * search from @first to find the next perag with the given tag set.
+ */
+struct xfs_perag *
+xfs_perag_get_tag(
+ struct xfs_mount *mp,
+ xfs_agnumber_t first,
+ int tag)
+{
+ struct xfs_perag *pag;
+ int found;
+ int ref;
+
+ rcu_read_lock();
+ found = radix_tree_gang_lookup_tag(&mp->m_perag_tree,
+ (void **)&pag, first, 1, tag);
+ if (found <= 0) {
+ rcu_read_unlock();
+ return NULL;
+ }
+ ref = atomic_inc_return(&pag->pag_ref);
+ rcu_read_unlock();
+ trace_xfs_perag_get_tag(mp, pag->pag_agno, ref, _RET_IP_);
+ return pag;
+}
+
+void
+xfs_perag_put(
+ struct xfs_perag *pag)
+{
+ int ref;
+
+ ASSERT(atomic_read(&pag->pag_ref) > 0);
+ ref = atomic_dec_return(&pag->pag_ref);
+ trace_xfs_perag_put(pag->pag_mount, pag->pag_agno, ref, _RET_IP_);
+}
+
+/*
+ * Check the validity of the SB found.
+ */
+STATIC int
+xfs_mount_validate_sb(
+ xfs_mount_t *mp,
+ xfs_sb_t *sbp,
+ bool check_inprogress,
+ bool check_version)
+{
+
+ /*
+ * If the log device and data device have the
+ * same device number, the log is internal.
+ * Consequently, the sb_logstart should be non-zero. If
+ * we have a zero sb_logstart in this case, we may be trying to mount
+ * a volume filesystem in a non-volume manner.
+ */
+ if (sbp->sb_magicnum != XFS_SB_MAGIC) {
+ xfs_warn(mp, "bad magic number");
+ return XFS_ERROR(EWRONGFS);
+ }
+
+
+ if (!xfs_sb_good_version(sbp)) {
+ xfs_warn(mp, "bad version");
+ return XFS_ERROR(EWRONGFS);
+ }
+
+ if ((sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) &&
+ (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
+ XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))) {
+ xfs_notice(mp,
+"Super block has XFS_OQUOTA bits along with XFS_PQUOTA and/or XFS_GQUOTA bits.\n");
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+
+ /*
+ * Version 5 superblock feature mask validation. Reject combinations the
+ * kernel cannot support up front before checking anything else. For
+ * write validation, we don't need to check feature masks.
+ */
+ if (check_version && XFS_SB_VERSION_NUM(sbp) == XFS_SB_VERSION_5) {
+ xfs_alert(mp,
+"Version 5 superblock detected. This kernel has EXPERIMENTAL support enabled!\n"
+"Use of these features in this kernel is at your own risk!");
+
+ if (xfs_sb_has_compat_feature(sbp,
+ XFS_SB_FEAT_COMPAT_UNKNOWN)) {
+ xfs_warn(mp,
+"Superblock has unknown compatible features (0x%x) enabled.\n"
+"Using a more recent kernel is recommended.",
+ (sbp->sb_features_compat &
+ XFS_SB_FEAT_COMPAT_UNKNOWN));
+ }
+
+ if (xfs_sb_has_ro_compat_feature(sbp,
+ XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) {
+ xfs_alert(mp,
+"Superblock has unknown read-only compatible features (0x%x) enabled.",
+ (sbp->sb_features_ro_compat &
+ XFS_SB_FEAT_RO_COMPAT_UNKNOWN));
+ if (!(mp->m_flags & XFS_MOUNT_RDONLY)) {
+ xfs_warn(mp,
+"Attempted to mount read-only compatible filesystem read-write.\n"
+"Filesystem can only be safely mounted read only.");
+ return XFS_ERROR(EINVAL);
+ }
+ }
+ if (xfs_sb_has_incompat_feature(sbp,
+ XFS_SB_FEAT_INCOMPAT_UNKNOWN)) {
+ xfs_warn(mp,
+"Superblock has unknown incompatible features (0x%x) enabled.\n"
+"Filesystem can not be safely mounted by this kernel.",
+ (sbp->sb_features_incompat &
+ XFS_SB_FEAT_INCOMPAT_UNKNOWN));
+ return XFS_ERROR(EINVAL);
+ }
+ }
+
+ if (unlikely(
+ sbp->sb_logstart == 0 && mp->m_logdev_targp == mp->m_ddev_targp)) {
+ xfs_warn(mp,
+ "filesystem is marked as having an external log; "
+ "specify logdev on the mount command line.");
+ return XFS_ERROR(EINVAL);
+ }
+
+ if (unlikely(
+ sbp->sb_logstart != 0 && mp->m_logdev_targp != mp->m_ddev_targp)) {
+ xfs_warn(mp,
+ "filesystem is marked as having an internal log; "
+ "do not specify logdev on the mount command line.");
+ return XFS_ERROR(EINVAL);
+ }
+
+ /*
+ * More sanity checking. Most of these were stolen directly from
+ * xfs_repair.
+ */
+ if (unlikely(
+ sbp->sb_agcount <= 0 ||
+ sbp->sb_sectsize < XFS_MIN_SECTORSIZE ||
+ sbp->sb_sectsize > XFS_MAX_SECTORSIZE ||
+ sbp->sb_sectlog < XFS_MIN_SECTORSIZE_LOG ||
+ sbp->sb_sectlog > XFS_MAX_SECTORSIZE_LOG ||
+ sbp->sb_sectsize != (1 << sbp->sb_sectlog) ||
+ sbp->sb_blocksize < XFS_MIN_BLOCKSIZE ||
+ sbp->sb_blocksize > XFS_MAX_BLOCKSIZE ||
+ sbp->sb_blocklog < XFS_MIN_BLOCKSIZE_LOG ||
+ sbp->sb_blocklog > XFS_MAX_BLOCKSIZE_LOG ||
+ sbp->sb_blocksize != (1 << sbp->sb_blocklog) ||
+ sbp->sb_inodesize < XFS_DINODE_MIN_SIZE ||
+ sbp->sb_inodesize > XFS_DINODE_MAX_SIZE ||
+ sbp->sb_inodelog < XFS_DINODE_MIN_LOG ||
+ sbp->sb_inodelog > XFS_DINODE_MAX_LOG ||
+ sbp->sb_inodesize != (1 << sbp->sb_inodelog) ||
+ (sbp->sb_blocklog - sbp->sb_inodelog != sbp->sb_inopblog) ||
+ (sbp->sb_rextsize * sbp->sb_blocksize > XFS_MAX_RTEXTSIZE) ||
+ (sbp->sb_rextsize * sbp->sb_blocksize < XFS_MIN_RTEXTSIZE) ||
+ (sbp->sb_imax_pct > 100 /* zero sb_imax_pct is valid */) ||
+ sbp->sb_dblocks == 0 ||
+ sbp->sb_dblocks > XFS_MAX_DBLOCKS(sbp) ||
+ sbp->sb_dblocks < XFS_MIN_DBLOCKS(sbp))) {
+ XFS_CORRUPTION_ERROR("SB sanity check failed",
+ XFS_ERRLEVEL_LOW, mp, sbp);
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+
+ /*
+ * Until this is fixed only page-sized or smaller data blocks work.
+ */
+ if (unlikely(sbp->sb_blocksize > PAGE_SIZE)) {
+ xfs_warn(mp,
+ "File system with blocksize %d bytes. "
+ "Only pagesize (%ld) or less will currently work.",
+ sbp->sb_blocksize, PAGE_SIZE);
+ return XFS_ERROR(ENOSYS);
+ }
+
+ /*
+ * Currently only very few inode sizes are supported.
+ */
+ switch (sbp->sb_inodesize) {
+ case 256:
+ case 512:
+ case 1024:
+ case 2048:
+ break;
+ default:
+ xfs_warn(mp, "inode size of %d bytes not supported",
+ sbp->sb_inodesize);
+ return XFS_ERROR(ENOSYS);
+ }
+
+ if (xfs_sb_validate_fsb_count(sbp, sbp->sb_dblocks) ||
+ xfs_sb_validate_fsb_count(sbp, sbp->sb_rblocks)) {
+ xfs_warn(mp,
+ "file system too large to be mounted on this system.");
+ return XFS_ERROR(EFBIG);
+ }
+
+ if (check_inprogress && sbp->sb_inprogress) {
+ xfs_warn(mp, "Offline file system operation in progress!");
+ return XFS_ERROR(EFSCORRUPTED);
+ }
+
+ /*
+ * Version 1 directory format has never worked on Linux.
+ */
+ if (unlikely(!xfs_sb_version_hasdirv2(sbp))) {
+ xfs_warn(mp, "file system using version 1 directory format");
+ return XFS_ERROR(ENOSYS);
+ }
+
+ return 0;
+}
+
+void
+xfs_sb_quota_from_disk(
+ struct xfs_sb *sbp)
+{
+ if (sbp->sb_qflags & XFS_OQUOTA_ENFD) {
+ sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
+ XFS_PQUOTA_ENFD : XFS_GQUOTA_ENFD;
+ }
+ if (sbp->sb_qflags & XFS_OQUOTA_CHKD) {
+ sbp->sb_qflags |= (sbp->sb_qflags & XFS_PQUOTA_ACCT) ?
+ XFS_PQUOTA_CHKD : XFS_GQUOTA_CHKD;
+ }
+ sbp->sb_qflags &= ~(XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD);
+}
+
+void
+xfs_sb_from_disk(
+ struct xfs_sb *to,
+ xfs_dsb_t *from)
+{
+ to->sb_magicnum = be32_to_cpu(from->sb_magicnum);
+ to->sb_blocksize = be32_to_cpu(from->sb_blocksize);
+ to->sb_dblocks = be64_to_cpu(from->sb_dblocks);
+ to->sb_rblocks = be64_to_cpu(from->sb_rblocks);
+ to->sb_rextents = be64_to_cpu(from->sb_rextents);
+ memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
+ to->sb_logstart = be64_to_cpu(from->sb_logstart);
+ to->sb_rootino = be64_to_cpu(from->sb_rootino);
+ to->sb_rbmino = be64_to_cpu(from->sb_rbmino);
+ to->sb_rsumino = be64_to_cpu(from->sb_rsumino);
+ to->sb_rextsize = be32_to_cpu(from->sb_rextsize);
+ to->sb_agblocks = be32_to_cpu(from->sb_agblocks);
+ to->sb_agcount = be32_to_cpu(from->sb_agcount);
+ to->sb_rbmblocks = be32_to_cpu(from->sb_rbmblocks);
+ to->sb_logblocks = be32_to_cpu(from->sb_logblocks);
+ to->sb_versionnum = be16_to_cpu(from->sb_versionnum);
+ to->sb_sectsize = be16_to_cpu(from->sb_sectsize);
+ to->sb_inodesize = be16_to_cpu(from->sb_inodesize);
+ to->sb_inopblock = be16_to_cpu(from->sb_inopblock);
+ memcpy(&to->sb_fname, &from->sb_fname, sizeof(to->sb_fname));
+ to->sb_blocklog = from->sb_blocklog;
+ to->sb_sectlog = from->sb_sectlog;
+ to->sb_inodelog = from->sb_inodelog;
+ to->sb_inopblog = from->sb_inopblog;
+ to->sb_agblklog = from->sb_agblklog;
+ to->sb_rextslog = from->sb_rextslog;
+ to->sb_inprogress = from->sb_inprogress;
+ to->sb_imax_pct = from->sb_imax_pct;
+ to->sb_icount = be64_to_cpu(from->sb_icount);
+ to->sb_ifree = be64_to_cpu(from->sb_ifree);
+ to->sb_fdblocks = be64_to_cpu(from->sb_fdblocks);
+ to->sb_frextents = be64_to_cpu(from->sb_frextents);
+ to->sb_uquotino = be64_to_cpu(from->sb_uquotino);
+ to->sb_gquotino = be64_to_cpu(from->sb_gquotino);
+ to->sb_qflags = be16_to_cpu(from->sb_qflags);
+ to->sb_flags = from->sb_flags;
+ to->sb_shared_vn = from->sb_shared_vn;
+ to->sb_inoalignmt = be32_to_cpu(from->sb_inoalignmt);
+ to->sb_unit = be32_to_cpu(from->sb_unit);
+ to->sb_width = be32_to_cpu(from->sb_width);
+ to->sb_dirblklog = from->sb_dirblklog;
+ to->sb_logsectlog = from->sb_logsectlog;
+ to->sb_logsectsize = be16_to_cpu(from->sb_logsectsize);
+ to->sb_logsunit = be32_to_cpu(from->sb_logsunit);
+ to->sb_features2 = be32_to_cpu(from->sb_features2);
+ to->sb_bad_features2 = be32_to_cpu(from->sb_bad_features2);
+ to->sb_features_compat = be32_to_cpu(from->sb_features_compat);
+ to->sb_features_ro_compat = be32_to_cpu(from->sb_features_ro_compat);
+ to->sb_features_incompat = be32_to_cpu(from->sb_features_incompat);
+ to->sb_features_log_incompat =
+ be32_to_cpu(from->sb_features_log_incompat);
+ to->sb_pad = 0;
+ to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
+ to->sb_lsn = be64_to_cpu(from->sb_lsn);
+}
+
+static void
+xfs_sb_quota_to_disk(
+ xfs_dsb_t *to,
+ xfs_sb_t *from,
+ __int64_t *fields)
+{
+ __uint16_t qflags = from->sb_qflags;
+
+ if (*fields & XFS_SB_QFLAGS) {
+ /*
+ * The in-core version of sb_qflags do not have
+ * XFS_OQUOTA_* flags, whereas the on-disk version
+ * does. So, convert incore XFS_{PG}QUOTA_* flags
+ * to on-disk XFS_OQUOTA_* flags.
+ */
+ qflags &= ~(XFS_PQUOTA_ENFD | XFS_PQUOTA_CHKD |
+ XFS_GQUOTA_ENFD | XFS_GQUOTA_CHKD);
+
+ if (from->sb_qflags &
+ (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD))
+ qflags |= XFS_OQUOTA_ENFD;
+ if (from->sb_qflags &
+ (XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD))
+ qflags |= XFS_OQUOTA_CHKD;
+ to->sb_qflags = cpu_to_be16(qflags);
+ *fields &= ~XFS_SB_QFLAGS;
+ }
+}
+
+/*
+ * Copy in core superblock to ondisk one.
+ *
+ * The fields argument is mask of superblock fields to copy.
+ */
+void
+xfs_sb_to_disk(
+ xfs_dsb_t *to,
+ xfs_sb_t *from,
+ __int64_t fields)
+{
+ xfs_caddr_t to_ptr = (xfs_caddr_t)to;
+ xfs_caddr_t from_ptr = (xfs_caddr_t)from;
+ xfs_sb_field_t f;
+ int first;
+ int size;
+
+ ASSERT(fields);
+ if (!fields)
+ return;
+
+ xfs_sb_quota_to_disk(to, from, &fields);
+ while (fields) {
+ f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
+ first = xfs_sb_info[f].offset;
+ size = xfs_sb_info[f + 1].offset - first;
+
+ ASSERT(xfs_sb_info[f].type == 0 || xfs_sb_info[f].type == 1);
+
+ if (size == 1 || xfs_sb_info[f].type == 1) {
+ memcpy(to_ptr + first, from_ptr + first, size);
+ } else {
+ switch (size) {
+ case 2:
+ *(__be16 *)(to_ptr + first) =
+ cpu_to_be16(*(__u16 *)(from_ptr + first));
+ break;
+ case 4:
+ *(__be32 *)(to_ptr + first) =
+ cpu_to_be32(*(__u32 *)(from_ptr + first));
+ break;
+ case 8:
+ *(__be64 *)(to_ptr + first) =
+ cpu_to_be64(*(__u64 *)(from_ptr + first));
+ break;
+ default:
+ ASSERT(0);
+ }
+ }
+
+ fields &= ~(1LL << f);
+ }
+}
+
+static int
+xfs_sb_verify(
+ struct xfs_buf *bp,
+ bool check_version)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_sb sb;
+
+ xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp));
+
+ /*
+ * Only check the in progress field for the primary superblock as
+ * mkfs.xfs doesn't clear it from secondary superblocks.
+ */
+ return xfs_mount_validate_sb(mp, &sb, bp->b_bn == XFS_SB_DADDR,
+ check_version);
+}
+
+/*
+ * If the superblock has the CRC feature bit set or the CRC field is non-null,
+ * check that the CRC is valid. We check the CRC field is non-null because a
+ * single bit error could clear the feature bit and unused parts of the
+ * superblock are supposed to be zero. Hence a non-null crc field indicates that
+ * we've potentially lost a feature bit and we should check it anyway.
+ */
+static void
+xfs_sb_read_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp);
+ int error;
+
+ /*
+ * open code the version check to avoid needing to convert the entire
+ * superblock from disk order just to check the version number
+ */
+ if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC) &&
+ (((be16_to_cpu(dsb->sb_versionnum) & XFS_SB_VERSION_NUMBITS) ==
+ XFS_SB_VERSION_5) ||
+ dsb->sb_crc != 0)) {
+
+ if (!xfs_verify_cksum(bp->b_addr, be16_to_cpu(dsb->sb_sectsize),
+ offsetof(struct xfs_sb, sb_crc))) {
+ error = EFSCORRUPTED;
+ goto out_error;
+ }
+ }
+ error = xfs_sb_verify(bp, true);
+
+out_error:
+ if (error) {
+ XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
+ xfs_buf_ioerror(bp, error);
+ }
+}
+
+/*
+ * We may be probed for a filesystem match, so we may not want to emit
+ * messages when the superblock buffer is not actually an XFS superblock.
+ * If we find an XFS superblock, the run a normal, noisy mount because we are
+ * really going to mount it and want to know about errors.
+ */
+static void
+xfs_sb_quiet_read_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_dsb *dsb = XFS_BUF_TO_SBP(bp);
+
+
+ if (dsb->sb_magicnum == cpu_to_be32(XFS_SB_MAGIC)) {
+ /* XFS filesystem, verify noisily! */
+ xfs_sb_read_verify(bp);
+ return;
+ }
+ /* quietly fail */
+ xfs_buf_ioerror(bp, EWRONGFS);
+}
+
+static void
+xfs_sb_write_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_buf_log_item *bip = bp->b_fspriv;
+ int error;
+
+ error = xfs_sb_verify(bp, false);
+ if (error) {
+ XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp, bp->b_addr);
+ xfs_buf_ioerror(bp, error);
+ return;
+ }
+
+ if (!xfs_sb_version_hascrc(&mp->m_sb))
+ return;
+
+ if (bip)
+ XFS_BUF_TO_SBP(bp)->sb_lsn = cpu_to_be64(bip->bli_item.li_lsn);
+
+ xfs_update_cksum(bp->b_addr, BBTOB(bp->b_length),
+ offsetof(struct xfs_sb, sb_crc));
+}
+
+const struct xfs_buf_ops xfs_sb_buf_ops = {
+ .verify_read = xfs_sb_read_verify,
+ .verify_write = xfs_sb_write_verify,
+};
+
+const struct xfs_buf_ops xfs_sb_quiet_buf_ops = {
+ .verify_read = xfs_sb_quiet_read_verify,
+ .verify_write = xfs_sb_write_verify,
+};
+
+/*
+ * xfs_mount_common
+ *
+ * Mount initialization code establishing various mount
+ * fields from the superblock associated with the given
+ * mount structure
+ */
+void
+xfs_sb_mount_common(
+ struct xfs_mount *mp,
+ struct xfs_sb *sbp)
+{
+ mp->m_agfrotor = mp->m_agirotor = 0;
+ spin_lock_init(&mp->m_agirotor_lock);
+ mp->m_maxagi = mp->m_sb.sb_agcount;
+ mp->m_blkbit_log = sbp->sb_blocklog + XFS_NBBYLOG;
+ mp->m_blkbb_log = sbp->sb_blocklog - BBSHIFT;
+ mp->m_sectbb_log = sbp->sb_sectlog - BBSHIFT;
+ mp->m_agno_log = xfs_highbit32(sbp->sb_agcount - 1) + 1;
+ mp->m_agino_log = sbp->sb_inopblog + sbp->sb_agblklog;
+ mp->m_blockmask = sbp->sb_blocksize - 1;
+ mp->m_blockwsize = sbp->sb_blocksize >> XFS_WORDLOG;
+ mp->m_blockwmask = mp->m_blockwsize - 1;
+
+ mp->m_alloc_mxr[0] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 1);
+ mp->m_alloc_mxr[1] = xfs_allocbt_maxrecs(mp, sbp->sb_blocksize, 0);
+ mp->m_alloc_mnr[0] = mp->m_alloc_mxr[0] / 2;
+ mp->m_alloc_mnr[1] = mp->m_alloc_mxr[1] / 2;
+
+ mp->m_inobt_mxr[0] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 1);
+ mp->m_inobt_mxr[1] = xfs_inobt_maxrecs(mp, sbp->sb_blocksize, 0);
+ mp->m_inobt_mnr[0] = mp->m_inobt_mxr[0] / 2;
+ mp->m_inobt_mnr[1] = mp->m_inobt_mxr[1] / 2;
+
+ mp->m_bmap_dmxr[0] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 1);
+ mp->m_bmap_dmxr[1] = xfs_bmbt_maxrecs(mp, sbp->sb_blocksize, 0);
+ mp->m_bmap_dmnr[0] = mp->m_bmap_dmxr[0] / 2;
+ mp->m_bmap_dmnr[1] = mp->m_bmap_dmxr[1] / 2;
+
+ mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
+ mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
+ sbp->sb_inopblock);
+ mp->m_ialloc_blks = mp->m_ialloc_inos >> sbp->sb_inopblog;
+}
+
+/*
+ * xfs_initialize_perag_data
+ *
+ * Read in each per-ag structure so we can count up the number of
+ * allocated inodes, free inodes and used filesystem blocks as this
+ * information is no longer persistent in the superblock. Once we have
+ * this information, write it into the in-core superblock structure.
+ */
+int
+xfs_initialize_perag_data(
+ struct xfs_mount *mp,
+ xfs_agnumber_t agcount)
+{
+ xfs_agnumber_t index;
+ xfs_perag_t *pag;
+ xfs_sb_t *sbp = &mp->m_sb;
+ uint64_t ifree = 0;
+ uint64_t ialloc = 0;
+ uint64_t bfree = 0;
+ uint64_t bfreelst = 0;
+ uint64_t btree = 0;
+ int error;
+
+ for (index = 0; index < agcount; index++) {
+ /*
+ * read the agf, then the agi. This gets us
+ * all the information we need and populates the
+ * per-ag structures for us.
+ */
+ error = xfs_alloc_pagf_init(mp, NULL, index, 0);
+ if (error)
+ return error;
+
+ error = xfs_ialloc_pagi_init(mp, NULL, index);
+ if (error)
+ return error;
+ pag = xfs_perag_get(mp, index);
+ ifree += pag->pagi_freecount;
+ ialloc += pag->pagi_count;
+ bfree += pag->pagf_freeblks;
+ bfreelst += pag->pagf_flcount;
+ btree += pag->pagf_btreeblks;
+ xfs_perag_put(pag);
+ }
+ /*
+ * Overwrite incore superblock counters with just-read data
+ */
+ spin_lock(&mp->m_sb_lock);
+ sbp->sb_ifree = ifree;
+ sbp->sb_icount = ialloc;
+ sbp->sb_fdblocks = bfree + bfreelst + btree;
+ spin_unlock(&mp->m_sb_lock);
+
+ /* Fixup the per-cpu counters as well. */
+ xfs_icsb_reinit_counters(mp);
+
+ return 0;
+}
+
+/*
+ * xfs_mod_sb() can be used to copy arbitrary changes to the
+ * in-core superblock into the superblock buffer to be logged.
+ * It does not provide the higher level of locking that is
+ * needed to protect the in-core superblock from concurrent
+ * access.
+ */
+void
+xfs_mod_sb(xfs_trans_t *tp, __int64_t fields)
+{
+ xfs_buf_t *bp;
+ int first;
+ int last;
+ xfs_mount_t *mp;
+ xfs_sb_field_t f;
+
+ ASSERT(fields);
+ if (!fields)
+ return;
+ mp = tp->t_mountp;
+ bp = xfs_trans_getsb(tp, mp, 0);
+ first = sizeof(xfs_sb_t);
+ last = 0;
+
+ /* translate/copy */
+
+ xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb, fields);
+
+ /* find modified range */
+ f = (xfs_sb_field_t)xfs_highbit64((__uint64_t)fields);
+ ASSERT((1LL << f) & XFS_SB_MOD_BITS);
+ last = xfs_sb_info[f + 1].offset - 1;
+
+ f = (xfs_sb_field_t)xfs_lowbit64((__uint64_t)fields);
+ ASSERT((1LL << f) & XFS_SB_MOD_BITS);
+ first = xfs_sb_info[f].offset;
+
+ xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
+ xfs_trans_log_buf(tp, bp, first, last);
+}
diff --git a/fs/xfs/xfs_sb.h b/fs/xfs/xfs_sb.h
index 030f131..dea0373 100644
--- a/fs/xfs/xfs_sb.h
+++ b/fs/xfs/xfs_sb.h
@@ -26,6 +26,7 @@

struct xfs_buf;
struct xfs_mount;
+struct xfs_trans;

#define XFS_SB_MAGIC 0x58465342 /* 'XFSB' */
#define XFS_SB_VERSION_1 1 /* 5.3, 6.0.1, 6.1 */
@@ -667,4 +668,23 @@ xfs_is_quota_inode(struct xfs_sb *sbp, xfs_ino_t ino)
#define XFS_B_TO_FSBT(mp,b) (((__uint64_t)(b)) >> (mp)->m_sb.sb_blocklog)
#define XFS_B_FSB_OFFSET(mp,b) ((b) & (mp)->m_blockmask)

+/*
+ * perag get/put wrappers for ref counting
+ */
+extern struct xfs_perag *xfs_perag_get(struct xfs_mount *, xfs_agnumber_t);
+extern struct xfs_perag *xfs_perag_get_tag(struct xfs_mount *, xfs_agnumber_t,
+ int tag);
+extern void xfs_perag_put(struct xfs_perag *pag);
+extern int xfs_initialize_perag_data(struct xfs_mount *, xfs_agnumber_t);
+
+extern void xfs_sb_calc_crc(struct xfs_buf *);
+extern void xfs_mod_sb(struct xfs_trans *, __int64_t);
+extern void xfs_sb_mount_common(struct xfs_mount *, struct xfs_sb *);
+extern void xfs_sb_from_disk(struct xfs_sb *, struct xfs_dsb *);
+extern void xfs_sb_to_disk(struct xfs_dsb *, struct xfs_sb *, __int64_t);
+extern void xfs_sb_quota_from_disk(struct xfs_sb *sbp);
+
+extern const struct xfs_buf_ops xfs_sb_buf_ops;
+extern const struct xfs_buf_ops xfs_sb_quiet_buf_ops;
+
#endif /* __XFS_SB_H__ */
--
1.8.3.2