/*
* 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_defer.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"
#include "xfs_log.h"
#include "xfs_rmap_btree.h"
#include "xfs_bmap.h"
#include "xfs_refcount_btree.h"
#include "xfs_da_format.h"
#include "xfs_da_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)
{
uint32_t agcount = 0;
uint32_t rem;
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.",
(sbp->sb_features_compat &
XFS_SB_FEAT_COMPAT_UNKNOWN));
xfs_warn(mp,
"Using a more recent kernel is recommended.");
}