- 根目录:
- fs
- xfs
- xfs_sb.c
/*
* 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_ag.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_dinode.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.
*/
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);
}
/*
* 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 (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 XFS_ERROR(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 XFS_ERROR(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 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_notice(mp, "SB sanity check failed");
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)
{
/*
* 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;
}
}
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;
/*
* 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(from))
return;
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;
}
/*
* 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 ((*fields & XFS_SB_GQUOTINO) &&
(from->sb_qflags & XFS_GQUOTA_ACCT))
to->sb_gquotino = cpu_to_be64(from->sb_gquotino);
else if ((*fields & XFS_SB_PQUOTINO) &&
(from->sb_qflags & XFS_PQUOTA_ACCT))
to->sb_gquotino = cpu_to_be64(from->sb_pquotino);
*fields &= ~(XFS_SB_PQUOTINO | XFS_SB_GQUOTINO);
}
/*
* 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.
*
* 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_verify_cksum(bp->b_addr, BBTOB(bp->b_length),
offsetof(struct xfs_sb, sb_crc))) {
/* Only fail bad secondaries on a known V5 filesystem */
if (bp->b_bn == XFS_SB_DADDR ||
xfs_sb_version_hascrc(&mp->m_sb)) {
error = EFSCORRUPTED;
goto out_error;
}
}
}
error = xfs_sb_verify(bp, true);
out_error:
if (error) {
if (error == EFSCORRUPTED)
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, 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_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);
}