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Diffstat (limited to 'fs/xfs/libxfs/xfs_sb.c')
-rw-r--r--fs/xfs/libxfs/xfs_sb.c803
1 files changed, 803 insertions, 0 deletions
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
new file mode 100644
index 000000000..dc4bfc5d8
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -0,0 +1,803 @@
+/*
+ * 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_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_sb.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+#include "xfs_ialloc.h"
+#include "xfs_alloc.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+#include "xfs_trans.h"
+#include "xfs_buf_item.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_alloc_btree.h"
+#include "xfs_ialloc_btree.h"
+
+/*
+ * Physical superblock buffer manipulations. Shared with libxfs in userspace.
+ */
+
+/*
+ * 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 (sbp->sb_magicnum != XFS_SB_MAGIC) {
+ xfs_warn(mp, "bad magic number");
+ return -EWRONGFS;
+ }
+
+
+ if (!xfs_sb_good_version(sbp)) {
+ xfs_warn(mp, "bad version");
+ return -EWRONGFS;
+ }
+
+ /*
+ * 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) {
+ 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 -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 -EINVAL;
+ }
+ }
+
+ if (xfs_sb_version_has_pquotino(sbp)) {
+ if (sbp->sb_qflags & (XFS_OQUOTA_ENFD | XFS_OQUOTA_CHKD)) {
+ xfs_notice(mp,
+ "Version 5 of Super block has XFS_OQUOTA bits.");
+ return -EFSCORRUPTED;
+ }
+ } else if (sbp->sb_qflags & (XFS_PQUOTA_ENFD | XFS_GQUOTA_ENFD |
+ XFS_PQUOTA_CHKD | XFS_GQUOTA_CHKD)) {
+ xfs_notice(mp,
+"Superblock earlier than Version 5 has XFS_[PQ]UOTA_{ENFD|CHKD} bits.");
+ return -EFSCORRUPTED;
+ }
+
+ 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 -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 -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_dirblklog > XFS_MAX_BLOCKSIZE_LOG ||
+ 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_logsunit > XLOG_MAX_RECORD_BSIZE ||
+ sbp->sb_inopblock != howmany(sbp->sb_blocksize,sbp->sb_inodesize) ||
+ (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) ||
+ sbp->sb_shared_vn != 0)) {
+ xfs_notice(mp, "SB sanity check failed");
+ return -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 -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 -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 -EFBIG;
+ }
+
+ if (check_inprogress && sbp->sb_inprogress) {
+ xfs_warn(mp, "Offline file system operation in progress!");
+ return -EFSCORRUPTED;
+ }
+ return 0;
+}
+
+void
+xfs_sb_quota_from_disk(struct xfs_sb *sbp)
+{
+ /*
+ * older mkfs doesn't initialize quota inodes to NULLFSINO. This
+ * leads to in-core values having two different values for a quota
+ * inode to be invalid: 0 and NULLFSINO. Change it to a single value
+ * NULLFSINO.
+ *
+ * Note that this change affect only the in-core values. These
+ * values are not written back to disk unless any quota information
+ * is written to the disk. Even in that case, sb_pquotino field is
+ * not written to disk unless the superblock supports pquotino.
+ */
+ if (sbp->sb_uquotino == 0)
+ sbp->sb_uquotino = NULLFSINO;
+ if (sbp->sb_gquotino == 0)
+ sbp->sb_gquotino = NULLFSINO;
+ if (sbp->sb_pquotino == 0)
+ sbp->sb_pquotino = NULLFSINO;
+
+ /*
+ * We need to do these manipilations only if we are working
+ * with an older version of on-disk superblock.
+ */
+ if (xfs_sb_version_has_pquotino(sbp))
+ return;
+
+ 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);
+
+ if (sbp->sb_qflags & XFS_PQUOTA_ACCT) {
+ /*
+ * In older version of superblock, on-disk superblock only
+ * has sb_gquotino, and in-core superblock has both sb_gquotino
+ * and sb_pquotino. But, only one of them is supported at any
+ * point of time. So, if PQUOTA is set in disk superblock,
+ * copy over sb_gquotino to sb_pquotino.
+ */
+ sbp->sb_pquotino = sbp->sb_gquotino;
+ sbp->sb_gquotino = NULLFSINO;
+ }
+}
+
+static void
+__xfs_sb_from_disk(
+ struct xfs_sb *to,
+ xfs_dsb_t *from,
+ bool convert_xquota)
+{
+ 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);
+ /* crc is only used on disk, not in memory; just init to 0 here. */
+ to->sb_crc = 0;
+ to->sb_pad = 0;
+ to->sb_pquotino = be64_to_cpu(from->sb_pquotino);
+ to->sb_lsn = be64_to_cpu(from->sb_lsn);
+ /* Convert on-disk flags to in-memory flags? */
+ if (convert_xquota)
+ xfs_sb_quota_from_disk(to);
+}
+
+void
+xfs_sb_from_disk(
+ struct xfs_sb *to,
+ xfs_dsb_t *from)
+{
+ __xfs_sb_from_disk(to, from, true);
+}
+
+static void
+xfs_sb_quota_to_disk(
+ struct xfs_dsb *to,
+ struct xfs_sb *from)
+{
+ __uint16_t qflags = from->sb_qflags;
+
+ to->sb_uquotino = cpu_to_be64(from->sb_uquotino);
+ if (xfs_sb_version_has_pquotino(from)) {
+ to->sb_qflags = cpu_to_be16(from->sb_qflags);
+ to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
+ to->sb_pquotino = cpu_to_be64(from->sb_pquotino);
+ return;
+ }
+
+ /*
+ * 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);
+
+ /*
+ * GQUOTINO and PQUOTINO cannot be used together in versions
+ * of superblock that do not have pquotino. from->sb_flags
+ * tells us which quota is active and should be copied to
+ * disk. If neither are active, we should NULL the inode.
+ *
+ * In all cases, the separate pquotino must remain 0 because it
+ * it beyond the "end" of the valid non-pquotino superblock.
+ */
+ if (from->sb_qflags & XFS_GQUOTA_ACCT)
+ to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
+ else if (from->sb_qflags & XFS_PQUOTA_ACCT)
+ to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
+ else {
+ /*
+ * We can't rely on just the fields being logged to tell us
+ * that it is safe to write NULLFSINO - we should only do that
+ * if quotas are not actually enabled. Hence only write
+ * NULLFSINO if both in-core quota inodes are NULL.
+ */
+ if (from->sb_gquotino == NULLFSINO &&
+ from->sb_pquotino == NULLFSINO)
+ to->sb_gquotino = cpu_to_be64(NULLFSINO);
+ }
+
+ to->sb_pquotino = 0;
+}
+
+void
+xfs_sb_to_disk(
+ struct xfs_dsb *to,
+ struct xfs_sb *from)
+{
+ xfs_sb_quota_to_disk(to, from);
+
+ to->sb_magicnum = cpu_to_be32(from->sb_magicnum);
+ to->sb_blocksize = cpu_to_be32(from->sb_blocksize);
+ to->sb_dblocks = cpu_to_be64(from->sb_dblocks);
+ to->sb_rblocks = cpu_to_be64(from->sb_rblocks);
+ to->sb_rextents = cpu_to_be64(from->sb_rextents);
+ memcpy(&to->sb_uuid, &from->sb_uuid, sizeof(to->sb_uuid));
+ to->sb_logstart = cpu_to_be64(from->sb_logstart);
+ to->sb_rootino = cpu_to_be64(from->sb_rootino);
+ to->sb_rbmino = cpu_to_be64(from->sb_rbmino);
+ to->sb_rsumino = cpu_to_be64(from->sb_rsumino);
+ to->sb_rextsize = cpu_to_be32(from->sb_rextsize);
+ to->sb_agblocks = cpu_to_be32(from->sb_agblocks);
+ to->sb_agcount = cpu_to_be32(from->sb_agcount);
+ to->sb_rbmblocks = cpu_to_be32(from->sb_rbmblocks);
+ to->sb_logblocks = cpu_to_be32(from->sb_logblocks);
+ to->sb_versionnum = cpu_to_be16(from->sb_versionnum);
+ to->sb_sectsize = cpu_to_be16(from->sb_sectsize);
+ to->sb_inodesize = cpu_to_be16(from->sb_inodesize);
+ to->sb_inopblock = cpu_to_be16(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 = cpu_to_be64(from->sb_icount);
+ to->sb_ifree = cpu_to_be64(from->sb_ifree);
+ to->sb_fdblocks = cpu_to_be64(from->sb_fdblocks);
+ to->sb_frextents = cpu_to_be64(from->sb_frextents);
+
+ to->sb_flags = from->sb_flags;
+ to->sb_shared_vn = from->sb_shared_vn;
+ to->sb_inoalignmt = cpu_to_be32(from->sb_inoalignmt);
+ to->sb_unit = cpu_to_be32(from->sb_unit);
+ to->sb_width = cpu_to_be32(from->sb_width);
+ to->sb_dirblklog = from->sb_dirblklog;
+ to->sb_logsectlog = from->sb_logsectlog;
+ to->sb_logsectsize = cpu_to_be16(from->sb_logsectsize);
+ to->sb_logsunit = cpu_to_be32(from->sb_logsunit);
+
+ /*
+ * We need to ensure that bad_features2 always matches features2.
+ * Hence we enforce that here rather than having to remember to do it
+ * everywhere else that updates features2.
+ */
+ from->sb_bad_features2 = from->sb_features2;
+ to->sb_features2 = cpu_to_be32(from->sb_features2);
+ to->sb_bad_features2 = cpu_to_be32(from->sb_bad_features2);
+
+ if (xfs_sb_version_hascrc(from)) {
+ to->sb_features_compat = cpu_to_be32(from->sb_features_compat);
+ to->sb_features_ro_compat =
+ cpu_to_be32(from->sb_features_ro_compat);
+ to->sb_features_incompat =
+ cpu_to_be32(from->sb_features_incompat);
+ to->sb_features_log_incompat =
+ cpu_to_be32(from->sb_features_log_incompat);
+ to->sb_pad = 0;
+ to->sb_lsn = cpu_to_be64(from->sb_lsn);
+ }
+}
+
+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;
+
+ /*
+ * Use call variant which doesn't convert quota flags from disk
+ * format, because xfs_mount_validate_sb checks the on-disk flags.
+ */
+ __xfs_sb_from_disk(&sb, XFS_BUF_TO_SBP(bp), false);
+
+ /*
+ * 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.
+ *
+ * However, past bugs (i.e. in growfs) left non-zeroed regions beyond the
+ * last field in V4 secondary superblocks. So for secondary superblocks,
+ * we are more forgiving, and ignore CRC failures if the primary doesn't
+ * indicate that the fs version is V5.
+ */
+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_buf_verify_cksum(bp, XFS_SB_CRC_OFF)) {
+ /* Only fail bad secondaries on a known V5 filesystem */
+ if (bp->b_bn == XFS_SB_DADDR ||
+ xfs_sb_version_hascrc(&mp->m_sb)) {
+ error = -EFSBADCRC;
+ goto out_error;
+ }
+ }
+ }
+ error = xfs_sb_verify(bp, true);
+
+out_error:
+ if (error) {
+ xfs_buf_ioerror(bp, error);
+ if (error == -EFSCORRUPTED || error == -EFSBADCRC)
+ xfs_verifier_error(bp);
+ }
+}
+
+/*
+ * 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, then 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_buf_ioerror(bp, error);
+ xfs_verifier_error(bp);
+ 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_buf_update_cksum(bp, XFS_SB_CRC_OFF);
+}
+
+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);
+
+ xfs_reinit_percpu_counters(mp);
+
+ return 0;
+}
+
+/*
+ * xfs_log_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_log_sb(
+ struct xfs_trans *tp)
+{
+ struct xfs_mount *mp = tp->t_mountp;
+ struct xfs_buf *bp = xfs_trans_getsb(tp, mp, 0);
+
+ mp->m_sb.sb_icount = percpu_counter_sum(&mp->m_icount);
+ mp->m_sb.sb_ifree = percpu_counter_sum(&mp->m_ifree);
+ mp->m_sb.sb_fdblocks = percpu_counter_sum(&mp->m_fdblocks);
+
+ xfs_sb_to_disk(XFS_BUF_TO_SBP(bp), &mp->m_sb);
+ xfs_trans_buf_set_type(tp, bp, XFS_BLFT_SB_BUF);
+ xfs_trans_log_buf(tp, bp, 0, sizeof(struct xfs_dsb));
+}
+
+/*
+ * xfs_sync_sb
+ *
+ * Sync the superblock to disk.
+ *
+ * Note that the caller is responsible for checking the frozen state of the
+ * filesystem. This procedure uses the non-blocking transaction allocator and
+ * thus will allow modifications to a frozen fs. This is required because this
+ * code can be called during the process of freezing where use of the high-level
+ * allocator would deadlock.
+ */
+int
+xfs_sync_sb(
+ struct xfs_mount *mp,
+ bool wait)
+{
+ struct xfs_trans *tp;
+ int error;
+
+ tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_CHANGE, KM_SLEEP);
+ error = xfs_trans_reserve(tp, &M_RES(mp)->tr_sb, 0, 0);
+ if (error) {
+ xfs_trans_cancel(tp, 0);
+ return error;
+ }
+
+ xfs_log_sb(tp);
+ if (wait)
+ xfs_trans_set_sync(tp);
+ return xfs_trans_commit(tp, 0);
+}