/* -*- mode: c; c-basic-offset: 8; -*-
   * vim: noexpandtab sw=8 ts=8 sts=0:
   *
   * super.c
   *
   * load/unload driver, mount/dismount volumes
   *
   * Copyright (C) 2002, 2004 Oracle.  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; either
   * version 2 of the License, or (at your option) any later version.
   *
   * This program is distributed in the hope that it will 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 to the
   * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   * Boston, MA 021110-1307, USA.
   */
  
  #include <linux/module.h>
  #include <linux/fs.h>
  #include <linux/types.h>
  #include <linux/slab.h>
  #include <linux/highmem.h>

  #include <linux/init.h>
  #include <linux/random.h>
  #include <linux/statfs.h>
  #include <linux/moduleparam.h>
  #include <linux/blkdev.h>
  #include <linux/socket.h>
  #include <linux/inet.h>
  #include <linux/parser.h>
  #include <linux/crc32.h>
  #include <linux/debugfs.h>

  #include <linux/mount.h>

  #include <linux/seq_file.h>

  #include <linux/quotaops.h>

  #include <linux/cleancache.h>

  #define CREATE_TRACE_POINTS
  #include "ocfs2_trace.h"

  #include <cluster/masklog.h>
  
  #include "ocfs2.h"
  
  /* this should be the only file to include a version 1 header */
  #include "ocfs1_fs_compat.h"
  
  #include "alloc.h"

  #include "aops.h"

  #include "blockcheck.h"

  #include "dlmglue.h"
  #include "export.h"
  #include "extent_map.h"
  #include "heartbeat.h"
  #include "inode.h"
  #include "journal.h"
  #include "localalloc.h"
  #include "namei.h"
  #include "slot_map.h"
  #include "super.h"
  #include "sysfile.h"
  #include "uptodate.h"
  #include "ver.h"

  #include "xattr.h"

  #include "quota.h"

  #include "refcounttree.h"

  #include "suballoc.h"

  
  #include "buffer_head_io.h"

  static struct kmem_cache *ocfs2_inode_cachep = NULL;

  struct kmem_cache *ocfs2_dquot_cachep;
  struct kmem_cache *ocfs2_qf_chunk_cachep;

  /* OCFS2 needs to schedule several different types of work which

   * require cluster locking, disk I/O, recovery waits, etc. Since these
   * types of work tend to be heavy we avoid using the kernel events
   * workqueue and schedule on our own. */
  struct workqueue_struct *ocfs2_wq = NULL;
  
  static struct dentry *ocfs2_debugfs_root = NULL;
  
  MODULE_AUTHOR("Oracle");
  MODULE_LICENSE("GPL");

  struct mount_options
  {

  	unsigned long	commit_interval;

  	unsigned long	mount_opt;
  	unsigned int	atime_quantum;
  	signed short	slot;

  	int		localalloc_opt;

  	unsigned int	resv_level;

  	int		dir_resv_level;

  	char		cluster_stack[OCFS2_STACK_LABEL_LEN + 1];

  };

  static int ocfs2_parse_options(struct super_block *sb, char *options,

  			       struct mount_options *mopt,

  			       int is_remount);

  static int ocfs2_check_set_options(struct super_block *sb,
  				   struct mount_options *options);

  static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt);

  static void ocfs2_put_super(struct super_block *sb);
  static int ocfs2_mount_volume(struct super_block *sb);
  static int ocfs2_remount(struct super_block *sb, int *flags, char *data);
  static void ocfs2_dismount_volume(struct super_block *sb, int mnt_err);
  static int ocfs2_initialize_mem_caches(void);
  static void ocfs2_free_mem_caches(void);
  static void ocfs2_delete_osb(struct ocfs2_super *osb);

  static int ocfs2_statfs(struct dentry *dentry, struct kstatfs *buf);

  
  static int ocfs2_sync_fs(struct super_block *sb, int wait);
  
  static int ocfs2_init_global_system_inodes(struct ocfs2_super *osb);
  static int ocfs2_init_local_system_inodes(struct ocfs2_super *osb);

  static void ocfs2_release_system_inodes(struct ocfs2_super *osb);

  static int ocfs2_check_volume(struct ocfs2_super *osb);
  static int ocfs2_verify_volume(struct ocfs2_dinode *di,
  			       struct buffer_head *bh,

  			       u32 sectsize,
  			       struct ocfs2_blockcheck_stats *stats);

  static int ocfs2_initialize_super(struct super_block *sb,
  				  struct buffer_head *bh,

  				  int sector_size,
  				  struct ocfs2_blockcheck_stats *stats);

  static int ocfs2_get_sector(struct super_block *sb,
  			    struct buffer_head **bh,
  			    int block,
  			    int sect_size);

  static struct inode *ocfs2_alloc_inode(struct super_block *sb);
  static void ocfs2_destroy_inode(struct inode *inode);

  static int ocfs2_susp_quotas(struct ocfs2_super *osb, int unsuspend);
  static int ocfs2_enable_quotas(struct ocfs2_super *osb);
  static void ocfs2_disable_quotas(struct ocfs2_super *osb);

  static const struct super_operations ocfs2_sops = {

  	.statfs		= ocfs2_statfs,
  	.alloc_inode	= ocfs2_alloc_inode,
  	.destroy_inode	= ocfs2_destroy_inode,
  	.drop_inode	= ocfs2_drop_inode,

  	.evict_inode	= ocfs2_evict_inode,

  	.sync_fs	= ocfs2_sync_fs,

  	.put_super	= ocfs2_put_super,
  	.remount_fs	= ocfs2_remount,

  	.show_options   = ocfs2_show_options,

  	.quota_read	= ocfs2_quota_read,
  	.quota_write	= ocfs2_quota_write,

  };
  
  enum {
  	Opt_barrier,
  	Opt_err_panic,
  	Opt_err_ro,
  	Opt_intr,
  	Opt_nointr,
  	Opt_hb_none,
  	Opt_hb_local,

  	Opt_hb_global,

  	Opt_data_ordered,
  	Opt_data_writeback,

  	Opt_atime_quantum,

  	Opt_slot,

  	Opt_commit,

  	Opt_localalloc,

  	Opt_localflocks,

  	Opt_stack,

  	Opt_user_xattr,
  	Opt_nouser_xattr,

  	Opt_inode64,

  	Opt_acl,
  	Opt_noacl,

  	Opt_usrquota,
  	Opt_grpquota,

  	Opt_coherency_buffered,
  	Opt_coherency_full,

  	Opt_resv_level,

  	Opt_dir_resv_level,

  	Opt_err,
  };

  static const match_table_t tokens = {

  	{Opt_barrier, "barrier=%u"},
  	{Opt_err_panic, "errors=panic"},
  	{Opt_err_ro, "errors=remount-ro"},
  	{Opt_intr, "intr"},
  	{Opt_nointr, "nointr"},
  	{Opt_hb_none, OCFS2_HB_NONE},
  	{Opt_hb_local, OCFS2_HB_LOCAL},

  	{Opt_hb_global, OCFS2_HB_GLOBAL},

  	{Opt_data_ordered, "data=ordered"},
  	{Opt_data_writeback, "data=writeback"},

  	{Opt_atime_quantum, "atime_quantum=%u"},

  	{Opt_slot, "preferred_slot=%u"},

  	{Opt_commit, "commit=%u"},

  	{Opt_localalloc, "localalloc=%d"},

  	{Opt_localflocks, "localflocks"},

  	{Opt_stack, "cluster_stack=%s"},

  	{Opt_user_xattr, "user_xattr"},
  	{Opt_nouser_xattr, "nouser_xattr"},

  	{Opt_inode64, "inode64"},

  	{Opt_acl, "acl"},
  	{Opt_noacl, "noacl"},

  	{Opt_usrquota, "usrquota"},
  	{Opt_grpquota, "grpquota"},

  	{Opt_coherency_buffered, "coherency=buffered"},
  	{Opt_coherency_full, "coherency=full"},

  	{Opt_resv_level, "resv_level=%u"},

  	{Opt_dir_resv_level, "dir_resv_level=%u"},

  	{Opt_err, NULL}
  };

  #ifdef CONFIG_DEBUG_FS
  static int ocfs2_osb_dump(struct ocfs2_super *osb, char *buf, int len)
  {

  	struct ocfs2_cluster_connection *cconn = osb->cconn;
  	struct ocfs2_recovery_map *rm = osb->recovery_map;

  	struct ocfs2_orphan_scan *os = &osb->osb_orphan_scan;
  	int i, out = 0;

  
  	out += snprintf(buf + out, len - out,
  			"%10s => Id: %-s  Uuid: %-s  Gen: 0x%X  Label: %-s
  ",
  			"Device", osb->dev_str, osb->uuid_str,
  			osb->fs_generation, osb->vol_label);
  
  	out += snprintf(buf + out, len - out,
  			"%10s => State: %d  Flags: 0x%lX
  ", "Volume",
  			atomic_read(&osb->vol_state), osb->osb_flags);
  
  	out += snprintf(buf + out, len - out,
  			"%10s => Block: %lu  Cluster: %d
  ", "Sizes",
  			osb->sb->s_blocksize, osb->s_clustersize);
  
  	out += snprintf(buf + out, len - out,
  			"%10s => Compat: 0x%X  Incompat: 0x%X  "
  			"ROcompat: 0x%X
  ",
  			"Features", osb->s_feature_compat,
  			osb->s_feature_incompat, osb->s_feature_ro_compat);
  
  	out += snprintf(buf + out, len - out,
  			"%10s => Opts: 0x%lX  AtimeQuanta: %u
  ", "Mount",
  			osb->s_mount_opt, osb->s_atime_quantum);

  	if (cconn) {
  		out += snprintf(buf + out, len - out,
  				"%10s => Stack: %s  Name: %*s  "
  				"Version: %d.%d
  ", "Cluster",
  				(*osb->osb_cluster_stack == '\0' ?
  				 "o2cb" : osb->osb_cluster_stack),
  				cconn->cc_namelen, cconn->cc_name,
  				cconn->cc_version.pv_major,
  				cconn->cc_version.pv_minor);
  	}

  
  	spin_lock(&osb->dc_task_lock);
  	out += snprintf(buf + out, len - out,
  			"%10s => Pid: %d  Count: %lu  WakeSeq: %lu  "
  			"WorkSeq: %lu
  ", "DownCnvt",

  			(osb->dc_task ?  task_pid_nr(osb->dc_task) : -1),
  			osb->blocked_lock_count, osb->dc_wake_sequence,
  			osb->dc_work_sequence);

  	spin_unlock(&osb->dc_task_lock);
  
  	spin_lock(&osb->osb_lock);
  	out += snprintf(buf + out, len - out, "%10s => Pid: %d  Nodes:",
  			"Recovery",
  			(osb->recovery_thread_task ?
  			 task_pid_nr(osb->recovery_thread_task) : -1));
  	if (rm->rm_used == 0)
  		out += snprintf(buf + out, len - out, " None
  ");
  	else {
  		for (i = 0; i < rm->rm_used; i++)
  			out += snprintf(buf + out, len - out, " %d",
  					rm->rm_entries[i]);
  		out += snprintf(buf + out, len - out, "
  ");
  	}
  	spin_unlock(&osb->osb_lock);
  
  	out += snprintf(buf + out, len - out,
  			"%10s => Pid: %d  Interval: %lu  Needs: %d
  ", "Commit",

  			(osb->commit_task ? task_pid_nr(osb->commit_task) : -1),
  			osb->osb_commit_interval,

  			atomic_read(&osb->needs_checkpoint));
  
  	out += snprintf(buf + out, len - out,

  			"%10s => State: %d  TxnId: %lu  NumTxns: %d
  ",

  			"Journal", osb->journal->j_state,

  			osb->journal->j_trans_id,
  			atomic_read(&osb->journal->j_num_trans));

  
  	out += snprintf(buf + out, len - out,
  			"%10s => GlobalAllocs: %d  LocalAllocs: %d  "
  			"SubAllocs: %d  LAWinMoves: %d  SAExtends: %d
  ",
  			"Stats",
  			atomic_read(&osb->alloc_stats.bitmap_data),
  			atomic_read(&osb->alloc_stats.local_data),
  			atomic_read(&osb->alloc_stats.bg_allocs),
  			atomic_read(&osb->alloc_stats.moves),
  			atomic_read(&osb->alloc_stats.bg_extends));
  
  	out += snprintf(buf + out, len - out,
  			"%10s => State: %u  Descriptor: %llu  Size: %u bits  "
  			"Default: %u bits
  ",
  			"LocalAlloc", osb->local_alloc_state,
  			(unsigned long long)osb->la_last_gd,
  			osb->local_alloc_bits, osb->local_alloc_default_bits);
  
  	spin_lock(&osb->osb_lock);
  	out += snprintf(buf + out, len - out,

  			"%10s => InodeSlot: %d  StolenInodes: %d, "
  			"MetaSlot: %d  StolenMeta: %d
  ", "Steal",

  			osb->s_inode_steal_slot,

  			atomic_read(&osb->s_num_inodes_stolen),
  			osb->s_meta_steal_slot,
  			atomic_read(&osb->s_num_meta_stolen));

  	spin_unlock(&osb->osb_lock);

  	out += snprintf(buf + out, len - out, "OrphanScan => ");
  	out += snprintf(buf + out, len - out, "Local: %u  Global: %u ",
  			os->os_count, os->os_seqno);
  	out += snprintf(buf + out, len - out, " Last Scan: ");
  	if (atomic_read(&os->os_state) == ORPHAN_SCAN_INACTIVE)
  		out += snprintf(buf + out, len - out, "Disabled
  ");
  	else
  		out += snprintf(buf + out, len - out, "%lu seconds ago
  ",
  				(get_seconds() - os->os_scantime.tv_sec));

  	out += snprintf(buf + out, len - out, "%10s => %3s  %10s
  ",
  			"Slots", "Num", "RecoGen");

  	for (i = 0; i < osb->max_slots; ++i) {
  		out += snprintf(buf + out, len - out,
  				"%10s  %c %3d  %10d
  ",
  				" ",
  				(i == osb->slot_num ? '*' : ' '),
  				i, osb->slot_recovery_generations[i]);
  	}
  
  	return out;
  }
  
  static int ocfs2_osb_debug_open(struct inode *inode, struct file *file)
  {
  	struct ocfs2_super *osb = inode->i_private;
  	char *buf = NULL;
  
  	buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
  	if (!buf)
  		goto bail;
  
  	i_size_write(inode, ocfs2_osb_dump(osb, buf, PAGE_SIZE));
  
  	file->private_data = buf;
  
  	return 0;
  bail:
  	return -ENOMEM;
  }
  
  static int ocfs2_debug_release(struct inode *inode, struct file *file)
  {
  	kfree(file->private_data);
  	return 0;
  }
  
  static ssize_t ocfs2_debug_read(struct file *file, char __user *buf,
  				size_t nbytes, loff_t *ppos)
  {
  	return simple_read_from_buffer(buf, nbytes, ppos, file->private_data,
  				       i_size_read(file->f_mapping->host));
  }
  #else
  static int ocfs2_osb_debug_open(struct inode *inode, struct file *file)
  {
  	return 0;
  }
  static int ocfs2_debug_release(struct inode *inode, struct file *file)
  {
  	return 0;
  }
  static ssize_t ocfs2_debug_read(struct file *file, char __user *buf,
  				size_t nbytes, loff_t *ppos)
  {
  	return 0;
  }
  #endif	/* CONFIG_DEBUG_FS */

  static const struct file_operations ocfs2_osb_debug_fops = {

  	.open =		ocfs2_osb_debug_open,
  	.release =	ocfs2_debug_release,
  	.read =		ocfs2_debug_read,
  	.llseek =	generic_file_llseek,
  };

  static int ocfs2_sync_fs(struct super_block *sb, int wait)
  {

  	int status;

  	tid_t target;
  	struct ocfs2_super *osb = OCFS2_SB(sb);

  	if (ocfs2_is_hard_readonly(osb))
  		return -EROFS;
  
  	if (wait) {
  		status = ocfs2_flush_truncate_log(osb);
  		if (status < 0)
  			mlog_errno(status);
  	} else {
  		ocfs2_schedule_truncate_log_flush(osb, 0);
  	}

  	if (jbd2_journal_start_commit(OCFS2_SB(sb)->journal->j_journal,
  				      &target)) {

  		if (wait)

  			jbd2_log_wait_commit(OCFS2_SB(sb)->journal->j_journal,
  					     target);

  	}
  	return 0;
  }

  static int ocfs2_need_system_inode(struct ocfs2_super *osb, int ino)
  {
  	if (!OCFS2_HAS_RO_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_RO_COMPAT_USRQUOTA)
  	    && (ino == USER_QUOTA_SYSTEM_INODE
  		|| ino == LOCAL_USER_QUOTA_SYSTEM_INODE))
  		return 0;
  	if (!OCFS2_HAS_RO_COMPAT_FEATURE(osb->sb, OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)
  	    && (ino == GROUP_QUOTA_SYSTEM_INODE
  		|| ino == LOCAL_GROUP_QUOTA_SYSTEM_INODE))
  		return 0;
  	return 1;
  }

  static int ocfs2_init_global_system_inodes(struct ocfs2_super *osb)
  {
  	struct inode *new = NULL;
  	int status = 0;
  	int i;

  	new = ocfs2_iget(osb, osb->root_blkno, OCFS2_FI_FLAG_SYSFILE, 0);

  	if (IS_ERR(new)) {
  		status = PTR_ERR(new);
  		mlog_errno(status);
  		goto bail;
  	}
  	osb->root_inode = new;

  	new = ocfs2_iget(osb, osb->system_dir_blkno, OCFS2_FI_FLAG_SYSFILE, 0);

  	if (IS_ERR(new)) {
  		status = PTR_ERR(new);
  		mlog_errno(status);
  		goto bail;
  	}
  	osb->sys_root_inode = new;
  
  	for (i = OCFS2_FIRST_ONLINE_SYSTEM_INODE;
  	     i <= OCFS2_LAST_GLOBAL_SYSTEM_INODE; i++) {

  		if (!ocfs2_need_system_inode(osb, i))
  			continue;

  		new = ocfs2_get_system_file_inode(osb, i, osb->slot_num);
  		if (!new) {
  			ocfs2_release_system_inodes(osb);
  			status = -EINVAL;
  			mlog_errno(status);
  			/* FIXME: Should ERROR_RO_FS */
  			mlog(ML_ERROR, "Unable to load system inode %d, "
  			     "possibly corrupt fs?", i);
  			goto bail;
  		}
  		// the array now has one ref, so drop this one
  		iput(new);
  	}
  
  bail:

  	if (status)
  		mlog_errno(status);

  	return status;
  }
  
  static int ocfs2_init_local_system_inodes(struct ocfs2_super *osb)
  {
  	struct inode *new = NULL;
  	int status = 0;
  	int i;

  	for (i = OCFS2_LAST_GLOBAL_SYSTEM_INODE + 1;
  	     i < NUM_SYSTEM_INODES;
  	     i++) {

  		if (!ocfs2_need_system_inode(osb, i))
  			continue;

  		new = ocfs2_get_system_file_inode(osb, i, osb->slot_num);
  		if (!new) {
  			ocfs2_release_system_inodes(osb);
  			status = -EINVAL;
  			mlog(ML_ERROR, "status=%d, sysfile=%d, slot=%d
  ",
  			     status, i, osb->slot_num);
  			goto bail;
  		}
  		/* the array now has one ref, so drop this one */
  		iput(new);
  	}
  
  bail:

  	if (status)
  		mlog_errno(status);

  	return status;
  }

  static void ocfs2_release_system_inodes(struct ocfs2_super *osb)

  {

  	int i;

  	struct inode *inode;

  	for (i = 0; i < NUM_GLOBAL_SYSTEM_INODES; i++) {
  		inode = osb->global_system_inodes[i];

  		if (inode) {
  			iput(inode);

  			osb->global_system_inodes[i] = NULL;

  		}
  	}
  
  	inode = osb->sys_root_inode;
  	if (inode) {
  		iput(inode);
  		osb->sys_root_inode = NULL;
  	}
  
  	inode = osb->root_inode;
  	if (inode) {
  		iput(inode);
  		osb->root_inode = NULL;
  	}

  	if (!osb->local_system_inodes)

  		return;

  
  	for (i = 0; i < NUM_LOCAL_SYSTEM_INODES * osb->max_slots; i++) {
  		if (osb->local_system_inodes[i]) {
  			iput(osb->local_system_inodes[i]);
  			osb->local_system_inodes[i] = NULL;
  		}
  	}
  
  	kfree(osb->local_system_inodes);
  	osb->local_system_inodes = NULL;

  }
  
  /* We're allocating fs objects, use GFP_NOFS */
  static struct inode *ocfs2_alloc_inode(struct super_block *sb)
  {
  	struct ocfs2_inode_info *oi;

  	oi = kmem_cache_alloc(ocfs2_inode_cachep, GFP_NOFS);

  	if (!oi)
  		return NULL;

  	jbd2_journal_init_jbd_inode(&oi->ip_jinode, &oi->vfs_inode);

  	return &oi->vfs_inode;
  }

  static void ocfs2_i_callback(struct rcu_head *head)

  {

  	struct inode *inode = container_of(head, struct inode, i_rcu);
  	INIT_LIST_HEAD(&inode->i_dentry);

  	kmem_cache_free(ocfs2_inode_cachep, OCFS2_I(inode));
  }

  static void ocfs2_destroy_inode(struct inode *inode)
  {
  	call_rcu(&inode->i_rcu, ocfs2_i_callback);
  }

  static unsigned long long ocfs2_max_file_offset(unsigned int bbits,
  						unsigned int cbits)

  {

  	unsigned int bytes = 1 << cbits;
  	unsigned int trim = bytes;
  	unsigned int bitshift = 32;
  
  	/*
  	 * i_size and all block offsets in ocfs2 are always 64 bits
  	 * wide. i_clusters is 32 bits, in cluster-sized units. So on
  	 * 64 bit platforms, cluster size will be the limiting factor.

  	 */
  
  #if BITS_PER_LONG == 32

  # if defined(CONFIG_LBDAF)

  	BUILD_BUG_ON(sizeof(sector_t) != 8);

  	/*
  	 * We might be limited by page cache size.
  	 */
  	if (bytes > PAGE_CACHE_SIZE) {
  		bytes = PAGE_CACHE_SIZE;
  		trim = 1;
  		/*
  		 * Shift by 31 here so that we don't get larger than
  		 * MAX_LFS_FILESIZE
  		 */
  		bitshift = 31;
  	}

  # else

  	/*
  	 * We are limited by the size of sector_t. Use block size, as
  	 * that's what we expose to the VFS.
  	 */
  	bytes = 1 << bbits;
  	trim = 1;
  	bitshift = 31;

  # endif
  #endif

  	/*
  	 * Trim by a whole cluster when we can actually approach the
  	 * on-disk limits. Otherwise we can overflow i_clusters when
  	 * an extent start is at the max offset.
  	 */
  	return (((unsigned long long)bytes) << bitshift) - trim;

  }
  
  static int ocfs2_remount(struct super_block *sb, int *flags, char *data)
  {
  	int incompat_features;
  	int ret = 0;

  	struct mount_options parsed_options;

  	struct ocfs2_super *osb = OCFS2_SB(sb);

  	u32 tmp;

  	if (!ocfs2_parse_options(sb, data, &parsed_options, 1) ||
  	    !ocfs2_check_set_options(sb, &parsed_options)) {

  		ret = -EINVAL;
  		goto out;
  	}

  	tmp = OCFS2_MOUNT_HB_LOCAL | OCFS2_MOUNT_HB_GLOBAL |
  		OCFS2_MOUNT_HB_NONE;
  	if ((osb->s_mount_opt & tmp) != (parsed_options.mount_opt & tmp)) {

  		ret = -EINVAL;
  		mlog(ML_ERROR, "Cannot change heartbeat mode on remount
  ");
  		goto out;
  	}
  
  	if ((osb->s_mount_opt & OCFS2_MOUNT_DATA_WRITEBACK) !=

  	    (parsed_options.mount_opt & OCFS2_MOUNT_DATA_WRITEBACK)) {

  		ret = -EINVAL;
  		mlog(ML_ERROR, "Cannot change data mode on remount
  ");
  		goto out;
  	}

  	/* Probably don't want this on remount; it might
  	 * mess with other nodes */
  	if (!(osb->s_mount_opt & OCFS2_MOUNT_INODE64) &&
  	    (parsed_options.mount_opt & OCFS2_MOUNT_INODE64)) {
  		ret = -EINVAL;
  		mlog(ML_ERROR, "Cannot enable inode64 on remount
  ");
  		goto out;
  	}

  	/* We're going to/from readonly mode. */
  	if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {

  		/* Disable quota accounting before remounting RO */
  		if (*flags & MS_RDONLY) {
  			ret = ocfs2_susp_quotas(osb, 0);
  			if (ret < 0)
  				goto out;
  		}

  		/* Lock here so the check of HARD_RO and the potential
  		 * setting of SOFT_RO is atomic. */
  		spin_lock(&osb->osb_lock);
  		if (osb->osb_flags & OCFS2_OSB_HARD_RO) {
  			mlog(ML_ERROR, "Remount on readonly device is forbidden.
  ");
  			ret = -EROFS;
  			goto unlock_osb;
  		}
  
  		if (*flags & MS_RDONLY) {

  			sb->s_flags |= MS_RDONLY;
  			osb->osb_flags |= OCFS2_OSB_SOFT_RO;
  		} else {

  			if (osb->osb_flags & OCFS2_OSB_ERROR_FS) {
  				mlog(ML_ERROR, "Cannot remount RDWR "
  				     "filesystem due to previous errors.
  ");
  				ret = -EROFS;
  				goto unlock_osb;
  			}
  			incompat_features = OCFS2_HAS_RO_COMPAT_FEATURE(sb, ~OCFS2_FEATURE_RO_COMPAT_SUPP);
  			if (incompat_features) {
  				mlog(ML_ERROR, "Cannot remount RDWR because "
  				     "of unsupported optional features "
  				     "(%x).
  ", incompat_features);
  				ret = -EINVAL;
  				goto unlock_osb;
  			}
  			sb->s_flags &= ~MS_RDONLY;
  			osb->osb_flags &= ~OCFS2_OSB_SOFT_RO;
  		}

  		trace_ocfs2_remount(sb->s_flags, osb->osb_flags, *flags);

  unlock_osb:
  		spin_unlock(&osb->osb_lock);

  		/* Enable quota accounting after remounting RW */
  		if (!ret && !(*flags & MS_RDONLY)) {
  			if (sb_any_quota_suspended(sb))
  				ret = ocfs2_susp_quotas(osb, 1);
  			else
  				ret = ocfs2_enable_quotas(osb);
  			if (ret < 0) {
  				/* Return back changes... */
  				spin_lock(&osb->osb_lock);
  				sb->s_flags |= MS_RDONLY;
  				osb->osb_flags |= OCFS2_OSB_SOFT_RO;
  				spin_unlock(&osb->osb_lock);
  				goto out;
  			}
  		}

  	}
  
  	if (!ret) {

  		/* Only save off the new mount options in case of a successful
  		 * remount. */

  		osb->s_mount_opt = parsed_options.mount_opt;
  		osb->s_atime_quantum = parsed_options.atime_quantum;
  		osb->preferred_slot = parsed_options.slot;

  		if (parsed_options.commit_interval)
  			osb->osb_commit_interval = parsed_options.commit_interval;

  
  		if (!ocfs2_is_hard_readonly(osb))
  			ocfs2_set_journal_params(osb);

  
  		sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
  			((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) ?
  							MS_POSIXACL : 0);

  	}
  out:
  	return ret;
  }
  
  static int ocfs2_sb_probe(struct super_block *sb,
  			  struct buffer_head **bh,

  			  int *sector_size,
  			  struct ocfs2_blockcheck_stats *stats)

  {

  	int status, tmpstat;

  	struct ocfs1_vol_disk_hdr *hdr;
  	struct ocfs2_dinode *di;
  	int blksize;
  
  	*bh = NULL;
  
  	/* may be > 512 */

  	*sector_size = bdev_logical_block_size(sb->s_bdev);

  	if (*sector_size > OCFS2_MAX_BLOCKSIZE) {
  		mlog(ML_ERROR, "Hardware sector size too large: %d (max=%d)
  ",
  		     *sector_size, OCFS2_MAX_BLOCKSIZE);
  		status = -EINVAL;
  		goto bail;
  	}
  
  	/* Can this really happen? */
  	if (*sector_size < OCFS2_MIN_BLOCKSIZE)
  		*sector_size = OCFS2_MIN_BLOCKSIZE;
  
  	/* check block zero for old format */
  	status = ocfs2_get_sector(sb, bh, 0, *sector_size);
  	if (status < 0) {
  		mlog_errno(status);
  		goto bail;
  	}
  	hdr = (struct ocfs1_vol_disk_hdr *) (*bh)->b_data;
  	if (hdr->major_version == OCFS1_MAJOR_VERSION) {
  		mlog(ML_ERROR, "incompatible version: %u.%u
  ",
  		     hdr->major_version, hdr->minor_version);
  		status = -EINVAL;
  	}
  	if (memcmp(hdr->signature, OCFS1_VOLUME_SIGNATURE,
  		   strlen(OCFS1_VOLUME_SIGNATURE)) == 0) {
  		mlog(ML_ERROR, "incompatible volume signature: %8s
  ",
  		     hdr->signature);
  		status = -EINVAL;
  	}
  	brelse(*bh);
  	*bh = NULL;
  	if (status < 0) {
  		mlog(ML_ERROR, "This is an ocfs v1 filesystem which must be "
  		     "upgraded before mounting with ocfs v2
  ");
  		goto bail;
  	}
  
  	/*
  	 * Now check at magic offset for 512, 1024, 2048, 4096
  	 * blocksizes.  4096 is the maximum blocksize because it is
  	 * the minimum clustersize.
  	 */
  	status = -EINVAL;
  	for (blksize = *sector_size;
  	     blksize <= OCFS2_MAX_BLOCKSIZE;
  	     blksize <<= 1) {
  		tmpstat = ocfs2_get_sector(sb, bh,
  					   OCFS2_SUPER_BLOCK_BLKNO,
  					   blksize);
  		if (tmpstat < 0) {
  			status = tmpstat;
  			mlog_errno(status);

  			break;

  		}
  		di = (struct ocfs2_dinode *) (*bh)->b_data;

  		memset(stats, 0, sizeof(struct ocfs2_blockcheck_stats));

  		spin_lock_init(&stats->b_lock);

  		tmpstat = ocfs2_verify_volume(di, *bh, blksize, stats);
  		if (tmpstat < 0) {
  			brelse(*bh);
  			*bh = NULL;
  		}
  		if (tmpstat != -EAGAIN) {
  			status = tmpstat;

  			break;

  		}

  	}
  
  bail:
  	return status;
  }

  static int ocfs2_verify_heartbeat(struct ocfs2_super *osb)
  {

  	u32 hb_enabled = OCFS2_MOUNT_HB_LOCAL | OCFS2_MOUNT_HB_GLOBAL;
  
  	if (osb->s_mount_opt & hb_enabled) {
  		if (ocfs2_mount_local(osb)) {

  			mlog(ML_ERROR, "Cannot heartbeat on a locally "
  			     "mounted device.
  ");
  			return -EINVAL;
  		}

  		if (ocfs2_userspace_stack(osb)) {

  			mlog(ML_ERROR, "Userspace stack expected, but "
  			     "o2cb heartbeat arguments passed to mount
  ");
  			return -EINVAL;
  		}

  		if (((osb->s_mount_opt & OCFS2_MOUNT_HB_GLOBAL) &&
  		     !ocfs2_cluster_o2cb_global_heartbeat(osb)) ||
  		    ((osb->s_mount_opt & OCFS2_MOUNT_HB_LOCAL) &&
  		     ocfs2_cluster_o2cb_global_heartbeat(osb))) {
  			mlog(ML_ERROR, "Mismatching o2cb heartbeat modes
  ");
  			return -EINVAL;
  		}

  	}

  	if (!(osb->s_mount_opt & hb_enabled)) {

  		if (!ocfs2_mount_local(osb) && !ocfs2_is_hard_readonly(osb) &&
  		    !ocfs2_userspace_stack(osb)) {

  			mlog(ML_ERROR, "Heartbeat has to be started to mount "
  			     "a read-write clustered device.
  ");
  			return -EINVAL;
  		}
  	}
  
  	return 0;
  }

  /*
   * If we're using a userspace stack, mount should have passed
   * a name that matches the disk.  If not, mount should not
   * have passed a stack.
   */
  static int ocfs2_verify_userspace_stack(struct ocfs2_super *osb,
  					struct mount_options *mopt)
  {
  	if (!ocfs2_userspace_stack(osb) && mopt->cluster_stack[0]) {
  		mlog(ML_ERROR,
  		     "cluster stack passed to mount, but this filesystem "
  		     "does not support it
  ");
  		return -EINVAL;
  	}
  
  	if (ocfs2_userspace_stack(osb) &&
  	    strncmp(osb->osb_cluster_stack, mopt->cluster_stack,
  		    OCFS2_STACK_LABEL_LEN)) {
  		mlog(ML_ERROR,
  		     "cluster stack passed to mount (\"%s\") does not "
  		     "match the filesystem (\"%s\")
  ",
  		     mopt->cluster_stack,
  		     osb->osb_cluster_stack);
  		return -EINVAL;
  	}
  
  	return 0;
  }

  static int ocfs2_susp_quotas(struct ocfs2_super *osb, int unsuspend)
  {
  	int type;
  	struct super_block *sb = osb->sb;
  	unsigned int feature[MAXQUOTAS] = { OCFS2_FEATURE_RO_COMPAT_USRQUOTA,
  					     OCFS2_FEATURE_RO_COMPAT_GRPQUOTA};
  	int status = 0;
  
  	for (type = 0; type < MAXQUOTAS; type++) {
  		if (!OCFS2_HAS_RO_COMPAT_FEATURE(sb, feature[type]))
  			continue;
  		if (unsuspend)

  			status = dquot_resume(sb, type);

  		else {
  			struct ocfs2_mem_dqinfo *oinfo;
  
  			/* Cancel periodic syncing before suspending */
  			oinfo = sb_dqinfo(sb, type)->dqi_priv;
  			cancel_delayed_work_sync(&oinfo->dqi_sync_work);

  			status = dquot_suspend(sb, type);

  		}

  		if (status < 0)
  			break;
  	}
  	if (status < 0)
  		mlog(ML_ERROR, "Failed to suspend/unsuspend quotas on "
  		     "remount (error = %d).
  ", status);
  	return status;
  }
  
  static int ocfs2_enable_quotas(struct ocfs2_super *osb)
  {
  	struct inode *inode[MAXQUOTAS] = { NULL, NULL };
  	struct super_block *sb = osb->sb;
  	unsigned int feature[MAXQUOTAS] = { OCFS2_FEATURE_RO_COMPAT_USRQUOTA,
  					     OCFS2_FEATURE_RO_COMPAT_GRPQUOTA};
  	unsigned int ino[MAXQUOTAS] = { LOCAL_USER_QUOTA_SYSTEM_INODE,
  					LOCAL_GROUP_QUOTA_SYSTEM_INODE };
  	int status;
  	int type;
  
  	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NEGATIVE_USAGE;
  	for (type = 0; type < MAXQUOTAS; type++) {
  		if (!OCFS2_HAS_RO_COMPAT_FEATURE(sb, feature[type]))
  			continue;
  		inode[type] = ocfs2_get_system_file_inode(osb, ino[type],
  							osb->slot_num);
  		if (!inode[type]) {
  			status = -ENOENT;
  			goto out_quota_off;
  		}

  		status = dquot_enable(inode[type], type, QFMT_OCFS2,
  				      DQUOT_USAGE_ENABLED);

  		if (status < 0)
  			goto out_quota_off;
  	}
  
  	for (type = 0; type < MAXQUOTAS; type++)
  		iput(inode[type]);
  	return 0;
  out_quota_off:
  	ocfs2_disable_quotas(osb);
  	for (type = 0; type < MAXQUOTAS; type++)
  		iput(inode[type]);
  	mlog_errno(status);
  	return status;
  }
  
  static void ocfs2_disable_quotas(struct ocfs2_super *osb)
  {
  	int type;
  	struct inode *inode;
  	struct super_block *sb = osb->sb;

  	struct ocfs2_mem_dqinfo *oinfo;

  
  	/* We mostly ignore errors in this function because there's not much
  	 * we can do when we see them */
  	for (type = 0; type < MAXQUOTAS; type++) {
  		if (!sb_has_quota_loaded(sb, type))
  			continue;

  		/* Cancel periodic syncing before we grab dqonoff_mutex */
  		oinfo = sb_dqinfo(sb, type)->dqi_priv;
  		cancel_delayed_work_sync(&oinfo->dqi_sync_work);

  		inode = igrab(sb->s_dquot.files[type]);
  		/* Turn off quotas. This will remove all dquot structures from
  		 * memory and so they will be automatically synced to global
  		 * quota files */

  		dquot_disable(sb, type, DQUOT_USAGE_ENABLED |
  					DQUOT_LIMITS_ENABLED);

  		if (!inode)
  			continue;
  		iput(inode);
  	}
  }
  
  /* Handle quota on quotactl */

  static int ocfs2_quota_on(struct super_block *sb, int type, int format_id)

  {
  	unsigned int feature[MAXQUOTAS] = { OCFS2_FEATURE_RO_COMPAT_USRQUOTA,
  					     OCFS2_FEATURE_RO_COMPAT_GRPQUOTA};
  
  	if (!OCFS2_HAS_RO_COMPAT_FEATURE(sb, feature[type]))
  		return -EINVAL;

  	return dquot_enable(sb_dqopt(sb)->files[type], type,
  			    format_id, DQUOT_LIMITS_ENABLED);

  }
  
  /* Handle quota off quotactl */

  static int ocfs2_quota_off(struct super_block *sb, int type)

  {

  	return dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);

  }

  static const struct quotactl_ops ocfs2_quotactl_ops = {

  	.quota_on_meta	= ocfs2_quota_on,

  	.quota_off	= ocfs2_quota_off,

  	.quota_sync	= dquot_quota_sync,
  	.get_info	= dquot_get_dqinfo,
  	.set_info	= dquot_set_dqinfo,
  	.get_dqblk	= dquot_get_dqblk,
  	.set_dqblk	= dquot_set_dqblk,

  };

  static int ocfs2_fill_super(struct super_block *sb, void *data, int silent)
  {
  	struct dentry *root;
  	int status, sector_size;

  	struct mount_options parsed_options;

  	struct inode *inode = NULL;
  	struct ocfs2_super *osb = NULL;
  	struct buffer_head *bh = NULL;

  	char nodestr[8];

  	struct ocfs2_blockcheck_stats stats;

  	trace_ocfs2_fill_super(sb, data, silent);

  	if (!ocfs2_parse_options(sb, data, &parsed_options, 0)) {

  		status = -EINVAL;
  		goto read_super_error;
  	}
  
  	/* probe for superblock */

  	status = ocfs2_sb_probe(sb, &bh, &sector_size, &stats);

  	if (status < 0) {
  		mlog(ML_ERROR, "superblock probe failed!
  ");
  		goto read_super_error;
  	}

  	status = ocfs2_initialize_super(sb, bh, sector_size, &stats);

  	osb = OCFS2_SB(sb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto read_super_error;
  	}
  	brelse(bh);
  	bh = NULL;

  	if (!ocfs2_check_set_options(sb, &parsed_options)) {
  		status = -EINVAL;
  		goto read_super_error;
  	}

  	osb->s_mount_opt = parsed_options.mount_opt;
  	osb->s_atime_quantum = parsed_options.atime_quantum;
  	osb->preferred_slot = parsed_options.slot;

  	osb->osb_commit_interval = parsed_options.commit_interval;

  
  	ocfs2_la_set_sizes(osb, parsed_options.localalloc_opt);

  	osb->osb_resv_level = parsed_options.resv_level;

  	osb->osb_dir_resv_level = parsed_options.resv_level;
  	if (parsed_options.dir_resv_level == -1)
  		osb->osb_dir_resv_level = parsed_options.resv_level;
  	else
  		osb->osb_dir_resv_level = parsed_options.dir_resv_level;

  	status = ocfs2_verify_userspace_stack(osb, &parsed_options);
  	if (status)
  		goto read_super_error;

  	sb->s_magic = OCFS2_SUPER_MAGIC;

  	sb->s_flags = (sb->s_flags & ~(MS_POSIXACL | MS_NOSEC)) |

  		((osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);

  	/* Hard readonly mode only if: bdev_read_only, MS_RDONLY,
  	 * heartbeat=none */
  	if (bdev_read_only(sb->s_bdev)) {
  		if (!(sb->s_flags & MS_RDONLY)) {
  			status = -EACCES;
  			mlog(ML_ERROR, "Readonly device detected but readonly "
  			     "mount was not specified.
  ");
  			goto read_super_error;
  		}
  
  		/* You should not be able to start a local heartbeat
  		 * on a readonly device. */
  		if (osb->s_mount_opt & OCFS2_MOUNT_HB_LOCAL) {
  			status = -EROFS;
  			mlog(ML_ERROR, "Local heartbeat specified on readonly "
  			     "device.
  ");
  			goto read_super_error;
  		}
  
  		status = ocfs2_check_journals_nolocks(osb);
  		if (status < 0) {
  			if (status == -EROFS)
  				mlog(ML_ERROR, "Recovery required on readonly "
  				     "file system, but write access is "
  				     "unavailable.
  ");
  			else

  				mlog_errno(status);

  			goto read_super_error;
  		}
  
  		ocfs2_set_ro_flag(osb, 1);

  		printk(KERN_NOTICE "ocfs2: Readonly device (%s) detected. "
  		       "Cluster services will not be used for this mount. "
  		       "Recovery will be skipped.
  ", osb->dev_str);

  	}
  
  	if (!ocfs2_is_hard_readonly(osb)) {

  		if (sb->s_flags & MS_RDONLY)
  			ocfs2_set_ro_flag(osb, 0);
  	}

  	status = ocfs2_verify_heartbeat(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto read_super_error;
  	}

  	osb->osb_debug_root = debugfs_create_dir(osb->uuid_str,
  						 ocfs2_debugfs_root);
  	if (!osb->osb_debug_root) {
  		status = -EINVAL;
  		mlog(ML_ERROR, "Unable to create per-mount debugfs root.
  ");
  		goto read_super_error;
  	}

  	osb->osb_ctxt = debugfs_create_file("fs_state", S_IFREG|S_IRUSR,
  					    osb->osb_debug_root,
  					    osb,
  					    &ocfs2_osb_debug_fops);
  	if (!osb->osb_ctxt) {
  		status = -EINVAL;
  		mlog_errno(status);
  		goto read_super_error;
  	}

  	if (ocfs2_meta_ecc(osb)) {
  		status = ocfs2_blockcheck_stats_debugfs_install(
  						&osb->osb_ecc_stats,
  						osb->osb_debug_root);
  		if (status) {
  			mlog(ML_ERROR,
  			     "Unable to create blockcheck statistics "
  			     "files
  ");
  			goto read_super_error;
  		}
  	}

  	status = ocfs2_mount_volume(sb);
  	if (osb->root_inode)
  		inode = igrab(osb->root_inode);
  
  	if (status < 0)
  		goto read_super_error;
  
  	if (!inode) {
  		status = -EIO;
  		mlog_errno(status);
  		goto read_super_error;
  	}
  
  	root = d_alloc_root(inode);
  	if (!root) {
  		status = -ENOMEM;
  		mlog_errno(status);
  		goto read_super_error;
  	}
  
  	sb->s_root = root;
  
  	ocfs2_complete_mount_recovery(osb);

  	if (ocfs2_mount_local(osb))
  		snprintf(nodestr, sizeof(nodestr), "local");
  	else

  		snprintf(nodestr, sizeof(nodestr), "%u", osb->node_num);

  
  	printk(KERN_INFO "ocfs2: Mounting device (%s) on (node %s, slot %d) "

  	       "with %s data mode.
  ",

  	       osb->dev_str, nodestr, osb->slot_num,

  	       osb->s_mount_opt & OCFS2_MOUNT_DATA_WRITEBACK ? "writeback" :
  	       "ordered");
  
  	atomic_set(&osb->vol_state, VOLUME_MOUNTED);
  	wake_up(&osb->osb_mount_event);

  	/* Now we can initialize quotas because we can afford to wait
  	 * for cluster locks recovery now. That also means that truncation
  	 * log recovery can happen but that waits for proper quota setup */
  	if (!(sb->s_flags & MS_RDONLY)) {
  		status = ocfs2_enable_quotas(osb);
  		if (status < 0) {
  			/* We have to err-out specially here because
  			 * s_root is already set */
  			mlog_errno(status);
  			atomic_set(&osb->vol_state, VOLUME_DISABLED);
  			wake_up(&osb->osb_mount_event);

  			return status;
  		}
  	}
  
  	ocfs2_complete_quota_recovery(osb);
  
  	/* Now we wake up again for processes waiting for quotas */
  	atomic_set(&osb->vol_state, VOLUME_MOUNTED_QUOTAS);
  	wake_up(&osb->osb_mount_event);

  	/* Start this when the mount is almost sure of being successful */

  	ocfs2_orphan_scan_start(osb);

  	return status;
  
  read_super_error:

  	brelse(bh);

  
  	if (inode)
  		iput(inode);
  
  	if (osb) {
  		atomic_set(&osb->vol_state, VOLUME_DISABLED);
  		wake_up(&osb->osb_mount_event);
  		ocfs2_dismount_volume(sb, 1);
  	}

  	if (status)
  		mlog_errno(status);

  	return status;
  }

  static struct dentry *ocfs2_mount(struct file_system_type *fs_type,

  			int flags,
  			const char *dev_name,

  			void *data)

  {

  	return mount_bdev(fs_type, flags, dev_name, data, ocfs2_fill_super);

  }

  static void ocfs2_kill_sb(struct super_block *sb)
  {
  	struct ocfs2_super *osb = OCFS2_SB(sb);

  	/* Failed mount? */
  	if (!osb || atomic_read(&osb->vol_state) == VOLUME_DISABLED)
  		goto out;

  	/* Prevent further queueing of inode drop events */
  	spin_lock(&dentry_list_lock);
  	ocfs2_set_osb_flag(osb, OCFS2_OSB_DROP_DENTRY_LOCK_IMMED);
  	spin_unlock(&dentry_list_lock);
  	/* Wait for work to finish and/or remove it */
  	cancel_work_sync(&osb->dentry_lock_work);

  out:

  	kill_block_super(sb);
  }

  static struct file_system_type ocfs2_fs_type = {
  	.owner          = THIS_MODULE,
  	.name           = "ocfs2",

  	.mount          = ocfs2_mount,

  	.kill_sb        = ocfs2_kill_sb,

  	.fs_flags       = FS_REQUIRES_DEV|FS_RENAME_DOES_D_MOVE,

  	.next           = NULL
  };

  static int ocfs2_check_set_options(struct super_block *sb,
  				   struct mount_options *options)
  {
  	if (options->mount_opt & OCFS2_MOUNT_USRQUOTA &&
  	    !OCFS2_HAS_RO_COMPAT_FEATURE(sb,
  					 OCFS2_FEATURE_RO_COMPAT_USRQUOTA)) {
  		mlog(ML_ERROR, "User quotas were requested, but this "
  		     "filesystem does not have the feature enabled.
  ");
  		return 0;
  	}
  	if (options->mount_opt & OCFS2_MOUNT_GRPQUOTA &&
  	    !OCFS2_HAS_RO_COMPAT_FEATURE(sb,
  					 OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)) {
  		mlog(ML_ERROR, "Group quotas were requested, but this "
  		     "filesystem does not have the feature enabled.
  ");
  		return 0;
  	}
  	if (options->mount_opt & OCFS2_MOUNT_POSIX_ACL &&
  	    !OCFS2_HAS_INCOMPAT_FEATURE(sb, OCFS2_FEATURE_INCOMPAT_XATTR)) {
  		mlog(ML_ERROR, "ACL support requested but extended attributes "
  		     "feature is not enabled
  ");
  		return 0;
  	}
  	/* No ACL setting specified? Use XATTR feature... */
  	if (!(options->mount_opt & (OCFS2_MOUNT_POSIX_ACL |
  				    OCFS2_MOUNT_NO_POSIX_ACL))) {
  		if (OCFS2_HAS_INCOMPAT_FEATURE(sb, OCFS2_FEATURE_INCOMPAT_XATTR))
  			options->mount_opt |= OCFS2_MOUNT_POSIX_ACL;
  		else
  			options->mount_opt |= OCFS2_MOUNT_NO_POSIX_ACL;
  	}
  	return 1;
  }

  static int ocfs2_parse_options(struct super_block *sb,
  			       char *options,

  			       struct mount_options *mopt,

  			       int is_remount)
  {

  	int status, user_stack = 0;

  	char *p;

  	u32 tmp;

  	trace_ocfs2_parse_options(is_remount, options ? options : "(none)");

  	mopt->commit_interval = 0;

  	mopt->mount_opt = OCFS2_MOUNT_NOINTR;

  	mopt->atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;
  	mopt->slot = OCFS2_INVALID_SLOT;

  	mopt->localalloc_opt = -1;

  	mopt->cluster_stack[0] = '\0';

  	mopt->resv_level = OCFS2_DEFAULT_RESV_LEVEL;

  	mopt->dir_resv_level = -1;

  
  	if (!options) {
  		status = 1;
  		goto bail;
  	}
  
  	while ((p = strsep(&options, ",")) != NULL) {
  		int token, option;
  		substring_t args[MAX_OPT_ARGS];
  
  		if (!*p)
  			continue;
  
  		token = match_token(p, tokens, args);
  		switch (token) {
  		case Opt_hb_local:

  			mopt->mount_opt |= OCFS2_MOUNT_HB_LOCAL;

  			break;
  		case Opt_hb_none:

  			mopt->mount_opt |= OCFS2_MOUNT_HB_NONE;
  			break;
  		case Opt_hb_global:
  			mopt->mount_opt |= OCFS2_MOUNT_HB_GLOBAL;

  			break;
  		case Opt_barrier:
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option)

  				mopt->mount_opt |= OCFS2_MOUNT_BARRIER;

  			else

  				mopt->mount_opt &= ~OCFS2_MOUNT_BARRIER;

  			break;
  		case Opt_intr:

  			mopt->mount_opt &= ~OCFS2_MOUNT_NOINTR;

  			break;
  		case Opt_nointr:

  			mopt->mount_opt |= OCFS2_MOUNT_NOINTR;

  			break;
  		case Opt_err_panic:

  			mopt->mount_opt |= OCFS2_MOUNT_ERRORS_PANIC;

  			break;
  		case Opt_err_ro:

  			mopt->mount_opt &= ~OCFS2_MOUNT_ERRORS_PANIC;

  			break;
  		case Opt_data_ordered:

  			mopt->mount_opt &= ~OCFS2_MOUNT_DATA_WRITEBACK;

  			break;
  		case Opt_data_writeback:

  			mopt->mount_opt |= OCFS2_MOUNT_DATA_WRITEBACK;

  			break;

  		case Opt_user_xattr:
  			mopt->mount_opt &= ~OCFS2_MOUNT_NOUSERXATTR;
  			break;
  		case Opt_nouser_xattr:
  			mopt->mount_opt |= OCFS2_MOUNT_NOUSERXATTR;
  			break;

  		case Opt_atime_quantum:
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option >= 0)

  				mopt->atime_quantum = option;

  			break;

  		case Opt_slot:
  			option = 0;
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option)

  				mopt->slot = (s16)option;

  			break;

  		case Opt_commit:
  			option = 0;
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option < 0)
  				return 0;
  			if (option == 0)

  				option = JBD2_DEFAULT_MAX_COMMIT_AGE;

  			mopt->commit_interval = HZ * option;
  			break;

  		case Opt_localalloc:
  			option = 0;
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}

  			if (option >= 0)

  				mopt->localalloc_opt = option;
  			break;

  		case Opt_localflocks:
  			/*
  			 * Changing this during remount could race
  			 * flock() requests, or "unbalance" existing
  			 * ones (e.g., a lock is taken in one mode but
  			 * dropped in the other). If users care enough
  			 * to flip locking modes during remount, we
  			 * could add a "local" flag to individual
  			 * flock structures for proper tracking of
  			 * state.
  			 */
  			if (!is_remount)
  				mopt->mount_opt |= OCFS2_MOUNT_LOCALFLOCKS;
  			break;

  		case Opt_stack:
  			/* Check both that the option we were passed
  			 * is of the right length and that it is a proper
  			 * string of the right length.
  			 */
  			if (((args[0].to - args[0].from) !=
  			     OCFS2_STACK_LABEL_LEN) ||
  			    (strnlen(args[0].from,
  				     OCFS2_STACK_LABEL_LEN) !=
  			     OCFS2_STACK_LABEL_LEN)) {
  				mlog(ML_ERROR,
  				     "Invalid cluster_stack option
  ");
  				status = 0;
  				goto bail;
  			}
  			memcpy(mopt->cluster_stack, args[0].from,
  			       OCFS2_STACK_LABEL_LEN);
  			mopt->cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';

  			/*
  			 * Open code the memcmp here as we don't have
  			 * an osb to pass to
  			 * ocfs2_userspace_stack().
  			 */
  			if (memcmp(mopt->cluster_stack,
  				   OCFS2_CLASSIC_CLUSTER_STACK,
  				   OCFS2_STACK_LABEL_LEN))
  				user_stack = 1;

  			break;

  		case Opt_inode64:
  			mopt->mount_opt |= OCFS2_MOUNT_INODE64;
  			break;

  		case Opt_usrquota:

  			mopt->mount_opt |= OCFS2_MOUNT_USRQUOTA;
  			break;
  		case Opt_grpquota:

  			mopt->mount_opt |= OCFS2_MOUNT_GRPQUOTA;
  			break;

  		case Opt_coherency_buffered:
  			mopt->mount_opt |= OCFS2_MOUNT_COHERENCY_BUFFERED;
  			break;
  		case Opt_coherency_full:
  			mopt->mount_opt &= ~OCFS2_MOUNT_COHERENCY_BUFFERED;
  			break;

  		case Opt_acl:
  			mopt->mount_opt |= OCFS2_MOUNT_POSIX_ACL;

  			mopt->mount_opt &= ~OCFS2_MOUNT_NO_POSIX_ACL;

  			break;
  		case Opt_noacl:

  			mopt->mount_opt |= OCFS2_MOUNT_NO_POSIX_ACL;

  			mopt->mount_opt &= ~OCFS2_MOUNT_POSIX_ACL;
  			break;

  		case Opt_resv_level:
  			if (is_remount)
  				break;
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option >= OCFS2_MIN_RESV_LEVEL &&
  			    option < OCFS2_MAX_RESV_LEVEL)
  				mopt->resv_level = option;
  			break;

  		case Opt_dir_resv_level:
  			if (is_remount)
  				break;
  			if (match_int(&args[0], &option)) {
  				status = 0;
  				goto bail;
  			}
  			if (option >= OCFS2_MIN_RESV_LEVEL &&
  			    option < OCFS2_MAX_RESV_LEVEL)
  				mopt->dir_resv_level = option;
  			break;

  		default:
  			mlog(ML_ERROR,
  			     "Unrecognized mount option \"%s\" "
  			     "or missing value
  ", p);
  			status = 0;
  			goto bail;
  		}
  	}

  	if (user_stack == 0) {
  		/* Ensure only one heartbeat mode */
  		tmp = mopt->mount_opt & (OCFS2_MOUNT_HB_LOCAL |
  					 OCFS2_MOUNT_HB_GLOBAL |
  					 OCFS2_MOUNT_HB_NONE);
  		if (hweight32(tmp) != 1) {
  			mlog(ML_ERROR, "Invalid heartbeat mount options
  ");
  			status = 0;
  			goto bail;
  		}

  	}

  	status = 1;
  
  bail:

  	return status;
  }

  static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
  {
  	struct ocfs2_super *osb = OCFS2_SB(mnt->mnt_sb);
  	unsigned long opts = osb->s_mount_opt;

  	unsigned int local_alloc_megs;

  	if (opts & (OCFS2_MOUNT_HB_LOCAL | OCFS2_MOUNT_HB_GLOBAL)) {
  		seq_printf(s, ",_netdev");
  		if (opts & OCFS2_MOUNT_HB_LOCAL)
  			seq_printf(s, ",%s", OCFS2_HB_LOCAL);
  		else
  			seq_printf(s, ",%s", OCFS2_HB_GLOBAL);
  	} else
  		seq_printf(s, ",%s", OCFS2_HB_NONE);

  
  	if (opts & OCFS2_MOUNT_NOINTR)
  		seq_printf(s, ",nointr");
  
  	if (opts & OCFS2_MOUNT_DATA_WRITEBACK)
  		seq_printf(s, ",data=writeback");
  	else
  		seq_printf(s, ",data=ordered");
  
  	if (opts & OCFS2_MOUNT_BARRIER)
  		seq_printf(s, ",barrier=1");
  
  	if (opts & OCFS2_MOUNT_ERRORS_PANIC)
  		seq_printf(s, ",errors=panic");
  	else
  		seq_printf(s, ",errors=remount-ro");
  
  	if (osb->preferred_slot != OCFS2_INVALID_SLOT)
  		seq_printf(s, ",preferred_slot=%d", osb->preferred_slot);

  	if (!(mnt->mnt_flags & MNT_NOATIME) && !(mnt->mnt_flags & MNT_RELATIME))

  		seq_printf(s, ",atime_quantum=%u", osb->s_atime_quantum);

  	if (osb->osb_commit_interval)
  		seq_printf(s, ",commit=%u",
  			   (unsigned) (osb->osb_commit_interval / HZ));

  	local_alloc_megs = osb->local_alloc_bits >> (20 - osb->s_clustersize_bits);

  	if (local_alloc_megs != ocfs2_la_default_mb(osb))

  		seq_printf(s, ",localalloc=%d", local_alloc_megs);

  	if (opts & OCFS2_MOUNT_LOCALFLOCKS)
  		seq_printf(s, ",localflocks,");

  	if (osb->osb_cluster_stack[0])
  		seq_printf(s, ",cluster_stack=%.*s", OCFS2_STACK_LABEL_LEN,
  			   osb->osb_cluster_stack);

  	if (opts & OCFS2_MOUNT_USRQUOTA)
  		seq_printf(s, ",usrquota");
  	if (opts & OCFS2_MOUNT_GRPQUOTA)
  		seq_printf(s, ",grpquota");

  	if (opts & OCFS2_MOUNT_COHERENCY_BUFFERED)
  		seq_printf(s, ",coherency=buffered");
  	else
  		seq_printf(s, ",coherency=full");

  	if (opts & OCFS2_MOUNT_NOUSERXATTR)
  		seq_printf(s, ",nouser_xattr");
  	else
  		seq_printf(s, ",user_xattr");

  	if (opts & OCFS2_MOUNT_INODE64)
  		seq_printf(s, ",inode64");

  	if (opts & OCFS2_MOUNT_POSIX_ACL)
  		seq_printf(s, ",acl");
  	else
  		seq_printf(s, ",noacl");

  	if (osb->osb_resv_level != OCFS2_DEFAULT_RESV_LEVEL)
  		seq_printf(s, ",resv_level=%d", osb->osb_resv_level);

  	if (osb->osb_dir_resv_level != osb->osb_resv_level)
  		seq_printf(s, ",dir_resv_level=%d", osb->osb_resv_level);

  	return 0;
  }

  wait_queue_head_t ocfs2__ioend_wq[OCFS2_IOEND_WQ_HASH_SZ];

  static int __init ocfs2_init(void)
  {

  	int status, i;

  	ocfs2_print_version();

  	for (i = 0; i < OCFS2_IOEND_WQ_HASH_SZ; i++)
  		init_waitqueue_head(&ocfs2__ioend_wq[i]);

  	status = init_ocfs2_uptodate_cache();
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}
  
  	status = ocfs2_initialize_mem_caches();
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}
  
  	ocfs2_wq = create_singlethread_workqueue("ocfs2_wq");
  	if (!ocfs2_wq) {
  		status = -ENOMEM;
  		goto leave;
  	}

  	ocfs2_debugfs_root = debugfs_create_dir("ocfs2", NULL);
  	if (!ocfs2_debugfs_root) {
  		status = -EFAULT;
  		mlog(ML_ERROR, "Unable to create ocfs2 debugfs root.
  ");
  	}

  	ocfs2_set_locking_protocol();

  	status = register_quota_format(&ocfs2_quota_format);

  leave:
  	if (status < 0) {
  		ocfs2_free_mem_caches();
  		exit_ocfs2_uptodate_cache();

  		mlog_errno(status);

  	}

  	if (status >= 0) {
  		return register_filesystem(&ocfs2_fs_type);
  	} else
  		return -1;
  }
  
  static void __exit ocfs2_exit(void)
  {

  	if (ocfs2_wq) {
  		flush_workqueue(ocfs2_wq);
  		destroy_workqueue(ocfs2_wq);
  	}

  	unregister_quota_format(&ocfs2_quota_format);

  	debugfs_remove(ocfs2_debugfs_root);
  
  	ocfs2_free_mem_caches();
  
  	unregister_filesystem(&ocfs2_fs_type);

  	exit_ocfs2_uptodate_cache();

  }
  
  static void ocfs2_put_super(struct super_block *sb)
  {

  	trace_ocfs2_put_super(sb);

  
  	ocfs2_sync_blockdev(sb);
  	ocfs2_dismount_volume(sb, 0);

  }

  static int ocfs2_statfs(struct dentry *dentry, struct kstatfs *buf)

  {
  	struct ocfs2_super *osb;
  	u32 numbits, freebits;
  	int status;
  	struct ocfs2_dinode *bm_lock;
  	struct buffer_head *bh = NULL;
  	struct inode *inode = NULL;

  	trace_ocfs2_statfs(dentry->d_sb, buf);

  	osb = OCFS2_SB(dentry->d_sb);

  
  	inode = ocfs2_get_system_file_inode(osb,
  					    GLOBAL_BITMAP_SYSTEM_INODE,
  					    OCFS2_INVALID_SLOT);
  	if (!inode) {
  		mlog(ML_ERROR, "failed to get bitmap inode
  ");
  		status = -EIO;
  		goto bail;
  	}

  	status = ocfs2_inode_lock(inode, &bh, 0);

  	if (status < 0) {
  		mlog_errno(status);
  		goto bail;
  	}
  
  	bm_lock = (struct ocfs2_dinode *) bh->b_data;
  
  	numbits = le32_to_cpu(bm_lock->id1.bitmap1.i_total);
  	freebits = numbits - le32_to_cpu(bm_lock->id1.bitmap1.i_used);
  
  	buf->f_type = OCFS2_SUPER_MAGIC;

  	buf->f_bsize = dentry->d_sb->s_blocksize;

  	buf->f_namelen = OCFS2_MAX_FILENAME_LEN;
  	buf->f_blocks = ((sector_t) numbits) *
  			(osb->s_clustersize >> osb->sb->s_blocksize_bits);
  	buf->f_bfree = ((sector_t) freebits) *
  		       (osb->s_clustersize >> osb->sb->s_blocksize_bits);
  	buf->f_bavail = buf->f_bfree;
  	buf->f_files = numbits;
  	buf->f_ffree = freebits;

  	buf->f_fsid.val[0] = crc32_le(0, osb->uuid_str, OCFS2_VOL_UUID_LEN)
  				& 0xFFFFFFFFUL;
  	buf->f_fsid.val[1] = crc32_le(0, osb->uuid_str + OCFS2_VOL_UUID_LEN,
  				OCFS2_VOL_UUID_LEN) & 0xFFFFFFFFUL;

  
  	brelse(bh);

  	ocfs2_inode_unlock(inode, 0);

  	status = 0;
  bail:
  	if (inode)
  		iput(inode);

  	if (status)
  		mlog_errno(status);

  
  	return status;
  }

  static void ocfs2_inode_init_once(void *data)

  {
  	struct ocfs2_inode_info *oi = data;

  	oi->ip_flags = 0;
  	oi->ip_open_count = 0;
  	spin_lock_init(&oi->ip_lock);
  	ocfs2_extent_map_init(&oi->vfs_inode);
  	INIT_LIST_HEAD(&oi->ip_io_markers);

  	oi->ip_dir_start_lookup = 0;

  	atomic_set(&oi->ip_unaligned_aio, 0);

  	init_rwsem(&oi->ip_alloc_sem);

  	init_rwsem(&oi->ip_xattr_sem);

  	mutex_init(&oi->ip_io_mutex);

  	oi->ip_blkno = 0ULL;
  	oi->ip_clusters = 0;

  	ocfs2_resv_init_once(&oi->ip_la_data_resv);

  	ocfs2_lock_res_init_once(&oi->ip_rw_lockres);

  	ocfs2_lock_res_init_once(&oi->ip_inode_lockres);

  	ocfs2_lock_res_init_once(&oi->ip_open_lockres);

  	ocfs2_metadata_cache_init(INODE_CACHE(&oi->vfs_inode),

  				  &ocfs2_inode_caching_ops);

  	inode_init_once(&oi->vfs_inode);

  }
  
  static int ocfs2_initialize_mem_caches(void)
  {
  	ocfs2_inode_cachep = kmem_cache_create("ocfs2_inode_cache",

  				       sizeof(struct ocfs2_inode_info),
  				       0,
  				       (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
  						SLAB_MEM_SPREAD),

  				       ocfs2_inode_init_once);

  	ocfs2_dquot_cachep = kmem_cache_create("ocfs2_dquot_cache",
  					sizeof(struct ocfs2_dquot),
  					0,
  					(SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
  						SLAB_MEM_SPREAD),
  					NULL);
  	ocfs2_qf_chunk_cachep = kmem_cache_create("ocfs2_qf_chunk_cache",
  					sizeof(struct ocfs2_quota_chunk),
  					0,
  					(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
  					NULL);
  	if (!ocfs2_inode_cachep || !ocfs2_dquot_cachep ||
  	    !ocfs2_qf_chunk_cachep) {
  		if (ocfs2_inode_cachep)
  			kmem_cache_destroy(ocfs2_inode_cachep);
  		if (ocfs2_dquot_cachep)
  			kmem_cache_destroy(ocfs2_dquot_cachep);
  		if (ocfs2_qf_chunk_cachep)
  			kmem_cache_destroy(ocfs2_qf_chunk_cachep);

  		return -ENOMEM;

  	}

  	return 0;
  }
  
  static void ocfs2_free_mem_caches(void)
  {
  	if (ocfs2_inode_cachep)
  		kmem_cache_destroy(ocfs2_inode_cachep);

  	ocfs2_inode_cachep = NULL;

  
  	if (ocfs2_dquot_cachep)
  		kmem_cache_destroy(ocfs2_dquot_cachep);
  	ocfs2_dquot_cachep = NULL;
  
  	if (ocfs2_qf_chunk_cachep)
  		kmem_cache_destroy(ocfs2_qf_chunk_cachep);
  	ocfs2_qf_chunk_cachep = NULL;

  }
  
  static int ocfs2_get_sector(struct super_block *sb,
  			    struct buffer_head **bh,
  			    int block,
  			    int sect_size)
  {
  	if (!sb_set_blocksize(sb, sect_size)) {
  		mlog(ML_ERROR, "unable to set blocksize
  ");
  		return -EIO;
  	}
  
  	*bh = sb_getblk(sb, block);
  	if (!*bh) {
  		mlog_errno(-EIO);
  		return -EIO;
  	}
  	lock_buffer(*bh);
  	if (!buffer_dirty(*bh))
  		clear_buffer_uptodate(*bh);
  	unlock_buffer(*bh);
  	ll_rw_block(READ, 1, bh);
  	wait_on_buffer(*bh);

  	if (!buffer_uptodate(*bh)) {
  		mlog_errno(-EIO);
  		brelse(*bh);
  		*bh = NULL;
  		return -EIO;
  	}

  	return 0;
  }

  static int ocfs2_mount_volume(struct super_block *sb)
  {
  	int status = 0;
  	int unlock_super = 0;
  	struct ocfs2_super *osb = OCFS2_SB(sb);

  	if (ocfs2_is_hard_readonly(osb))
  		goto leave;

  	status = ocfs2_dlm_init(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}

  	status = ocfs2_super_lock(osb, 1);
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}
  	unlock_super = 1;
  
  	/* This will load up the node map and add ourselves to it. */
  	status = ocfs2_find_slot(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}

  	/* load all node-local system inodes */
  	status = ocfs2_init_local_system_inodes(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}
  
  	status = ocfs2_check_volume(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto leave;
  	}
  
  	status = ocfs2_truncate_log_init(osb);

  	if (status < 0)

  		mlog_errno(status);

  leave:
  	if (unlock_super)
  		ocfs2_super_unlock(osb, 1);

  	return status;
  }

  static void ocfs2_dismount_volume(struct super_block *sb, int mnt_err)
  {

  	int tmp, hangup_needed = 0;

  	struct ocfs2_super *osb = NULL;

  	char nodestr[8];

  	trace_ocfs2_dismount_volume(sb);

  
  	BUG_ON(!sb);
  	osb = OCFS2_SB(sb);
  	BUG_ON(!osb);

  	debugfs_remove(osb->osb_ctxt);

  	/*
  	 * Flush inode dropping work queue so that deletes are
  	 * performed while the filesystem is still working
  	 */
  	ocfs2_drop_all_dl_inodes(osb);

  	/* Orphan scan should be stopped as early as possible */
  	ocfs2_orphan_scan_stop(osb);

  	ocfs2_disable_quotas(osb);

  	ocfs2_shutdown_local_alloc(osb);
  
  	ocfs2_truncate_log_shutdown(osb);

  	/* This will disable recovery and flush any recovery work. */
  	ocfs2_recovery_exit(osb);

  
  	ocfs2_journal_shutdown(osb);
  
  	ocfs2_sync_blockdev(sb);

  	ocfs2_purge_refcount_trees(osb);

  	/* No cluster connection means we've failed during mount, so skip
  	 * all the steps which depended on that to complete. */
  	if (osb->cconn) {

  		tmp = ocfs2_super_lock(osb, 1);
  		if (tmp < 0) {
  			mlog_errno(tmp);
  			return;
  		}

  	}

  	if (osb->slot_num != OCFS2_INVALID_SLOT)
  		ocfs2_put_slot(osb);

  	if (osb->cconn)

  		ocfs2_super_unlock(osb, 1);

  
  	ocfs2_release_system_inodes(osb);

  	/*

  	 * If we're dismounting due to mount error, mount.ocfs2 will clean
  	 * up heartbeat.  If we're a local mount, there is no heartbeat.
  	 * If we failed before we got a uuid_str yet, we can't stop
  	 * heartbeat.  Otherwise, do it.
  	 */

  	if (!mnt_err && !ocfs2_mount_local(osb) && osb->uuid_str &&
  	    !ocfs2_is_hard_readonly(osb))

  		hangup_needed = 1;
  
  	if (osb->cconn)
  		ocfs2_dlm_shutdown(osb, hangup_needed);

  	ocfs2_blockcheck_stats_debugfs_remove(&osb->osb_ecc_stats);

  	debugfs_remove(osb->osb_debug_root);
  
  	if (hangup_needed)

  		ocfs2_cluster_hangup(osb->uuid_str, strlen(osb->uuid_str));

  
  	atomic_set(&osb->vol_state, VOLUME_DISMOUNTED);

  	if (ocfs2_mount_local(osb))
  		snprintf(nodestr, sizeof(nodestr), "local");
  	else

  		snprintf(nodestr, sizeof(nodestr), "%u", osb->node_num);

  
  	printk(KERN_INFO "ocfs2: Unmounting device (%s) on (node %s)
  ",
  	       osb->dev_str, nodestr);

  
  	ocfs2_delete_osb(osb);
  	kfree(osb);
  	sb->s_dev = 0;
  	sb->s_fs_info = NULL;
  }
  
  static int ocfs2_setup_osb_uuid(struct ocfs2_super *osb, const unsigned char *uuid,
  				unsigned uuid_bytes)
  {
  	int i, ret;
  	char *ptr;
  
  	BUG_ON(uuid_bytes != OCFS2_VOL_UUID_LEN);

  	osb->uuid_str = kzalloc(OCFS2_VOL_UUID_LEN * 2 + 1, GFP_KERNEL);

  	if (osb->uuid_str == NULL)
  		return -ENOMEM;

  	for (i = 0, ptr = osb->uuid_str; i < OCFS2_VOL_UUID_LEN; i++) {
  		/* print with null */
  		ret = snprintf(ptr, 3, "%02X", uuid[i]);
  		if (ret != 2) /* drop super cleans up */
  			return -EINVAL;
  		/* then only advance past the last char */
  		ptr += 2;
  	}
  
  	return 0;
  }

  /* Make sure entire volume is addressable by our journal.  Requires
     osb_clusters_at_boot to be valid and for the journal to have been
     initialized by ocfs2_journal_init(). */
  static int ocfs2_journal_addressable(struct ocfs2_super *osb)
  {
  	int status = 0;
  	u64 max_block =
  		ocfs2_clusters_to_blocks(osb->sb,
  					 osb->osb_clusters_at_boot) - 1;
  
  	/* 32-bit block number is always OK. */
  	if (max_block <= (u32)~0ULL)
  		goto out;
  
  	/* Volume is "huge", so see if our journal is new enough to
  	   support it. */
  	if (!(OCFS2_HAS_COMPAT_FEATURE(osb->sb,
  				       OCFS2_FEATURE_COMPAT_JBD2_SB) &&
  	      jbd2_journal_check_used_features(osb->journal->j_journal, 0, 0,
  					       JBD2_FEATURE_INCOMPAT_64BIT))) {
  		mlog(ML_ERROR, "The journal cannot address the entire volume. "
  		     "Enable the 'block64' journal option with tunefs.ocfs2");
  		status = -EFBIG;
  		goto out;
  	}
  
   out:
  	return status;
  }

  static int ocfs2_initialize_super(struct super_block *sb,
  				  struct buffer_head *bh,

  				  int sector_size,
  				  struct ocfs2_blockcheck_stats *stats)

  {

  	int status;

  	int i, cbits, bbits;
  	struct ocfs2_dinode *di = (struct ocfs2_dinode *)bh->b_data;

  	struct inode *inode = NULL;

  	struct ocfs2_journal *journal;
  	__le32 uuid_net_key;
  	struct ocfs2_super *osb;

  	u64 total_blocks;

  	osb = kzalloc(sizeof(struct ocfs2_super), GFP_KERNEL);

  	if (!osb) {
  		status = -ENOMEM;
  		mlog_errno(status);
  		goto bail;
  	}
  
  	sb->s_fs_info = osb;
  	sb->s_op = &ocfs2_sops;

  	sb->s_d_op = &ocfs2_dentry_ops;

  	sb->s_export_op = &ocfs2_export_ops;

  	sb->s_qcop = &ocfs2_quotactl_ops;
  	sb->dq_op = &ocfs2_quota_operations;

  	sb->s_xattr = ocfs2_xattr_handlers;

  	sb->s_time_gran = 1;

  	sb->s_flags |= MS_NOATIME;
  	/* this is needed to support O_LARGEFILE */

  	cbits = le32_to_cpu(di->id2.i_super.s_clustersize_bits);
  	bbits = le32_to_cpu(di->id2.i_super.s_blocksize_bits);
  	sb->s_maxbytes = ocfs2_max_file_offset(bbits, cbits);

  	osb->osb_dx_mask = (1 << (cbits - bbits)) - 1;
  
  	for (i = 0; i < 3; i++)
  		osb->osb_dx_seed[i] = le32_to_cpu(di->id2.i_super.s_dx_seed[i]);
  	osb->osb_dx_seed[3] = le32_to_cpu(di->id2.i_super.s_uuid_hash);

  	osb->sb = sb;
  	/* Save off for ocfs2_rw_direct */
  	osb->s_sectsize_bits = blksize_bits(sector_size);

  	BUG_ON(!osb->s_sectsize_bits);

  	spin_lock_init(&osb->dc_task_lock);
  	init_waitqueue_head(&osb->dc_event);
  	osb->dc_work_sequence = 0;
  	osb->dc_wake_sequence = 0;

  	INIT_LIST_HEAD(&osb->blocked_lock_list);
  	osb->blocked_lock_count = 0;

  	spin_lock_init(&osb->osb_lock);

  	spin_lock_init(&osb->osb_xattr_lock);

  	ocfs2_init_steal_slots(osb);

  
  	atomic_set(&osb->alloc_stats.moves, 0);
  	atomic_set(&osb->alloc_stats.local_data, 0);
  	atomic_set(&osb->alloc_stats.bitmap_data, 0);
  	atomic_set(&osb->alloc_stats.bg_allocs, 0);
  	atomic_set(&osb->alloc_stats.bg_extends, 0);

  	/* Copy the blockcheck stats from the superblock probe */
  	osb->osb_ecc_stats = *stats;

  	ocfs2_init_node_maps(osb);
  
  	snprintf(osb->dev_str, sizeof(osb->dev_str), "%u,%u",
  		 MAJOR(osb->sb->s_dev), MINOR(osb->sb->s_dev));

  	osb->max_slots = le16_to_cpu(di->id2.i_super.s_max_slots);
  	if (osb->max_slots > OCFS2_MAX_SLOTS || osb->max_slots == 0) {
  		mlog(ML_ERROR, "Invalid number of node slots (%u)
  ",
  		     osb->max_slots);
  		status = -EINVAL;
  		goto bail;
  	}

  	ocfs2_orphan_scan_init(osb);

  	status = ocfs2_recovery_init(osb);
  	if (status) {
  		mlog(ML_ERROR, "Unable to initialize recovery state
  ");
  		mlog_errno(status);
  		goto bail;
  	}

  
  	init_waitqueue_head(&osb->checkpoint_event);
  	atomic_set(&osb->needs_checkpoint, 0);

  	osb->s_atime_quantum = OCFS2_DEFAULT_ATIME_QUANTUM;

  	osb->slot_num = OCFS2_INVALID_SLOT;

  	osb->s_xattr_inline_size = le16_to_cpu(
  					di->id2.i_super.s_xattr_inline_size);

  	osb->local_alloc_state = OCFS2_LA_UNUSED;
  	osb->local_alloc_bh = NULL;

  	INIT_DELAYED_WORK(&osb->la_enable_wq, ocfs2_la_enable_worker);

  	init_waitqueue_head(&osb->osb_mount_event);

  	status = ocfs2_resmap_init(osb, &osb->osb_la_resmap);
  	if (status) {
  		mlog_errno(status);
  		goto bail;
  	}

  	osb->vol_label = kmalloc(OCFS2_MAX_VOL_LABEL_LEN, GFP_KERNEL);
  	if (!osb->vol_label) {
  		mlog(ML_ERROR, "unable to alloc vol label
  ");
  		status = -ENOMEM;
  		goto bail;
  	}

  	osb->slot_recovery_generations =
  		kcalloc(osb->max_slots, sizeof(*osb->slot_recovery_generations),
  			GFP_KERNEL);
  	if (!osb->slot_recovery_generations) {
  		status = -ENOMEM;
  		mlog_errno(status);
  		goto bail;
  	}

  	init_waitqueue_head(&osb->osb_wipe_event);
  	osb->osb_orphan_wipes = kcalloc(osb->max_slots,
  					sizeof(*osb->osb_orphan_wipes),
  					GFP_KERNEL);
  	if (!osb->osb_orphan_wipes) {
  		status = -ENOMEM;
  		mlog_errno(status);
  		goto bail;
  	}

  	osb->osb_rf_lock_tree = RB_ROOT;

  	osb->s_feature_compat =
  		le32_to_cpu(OCFS2_RAW_SB(di)->s_feature_compat);
  	osb->s_feature_ro_compat =
  		le32_to_cpu(OCFS2_RAW_SB(di)->s_feature_ro_compat);
  	osb->s_feature_incompat =
  		le32_to_cpu(OCFS2_RAW_SB(di)->s_feature_incompat);
  
  	if ((i = OCFS2_HAS_INCOMPAT_FEATURE(osb->sb, ~OCFS2_FEATURE_INCOMPAT_SUPP))) {
  		mlog(ML_ERROR, "couldn't mount because of unsupported "
  		     "optional features (%x).
  ", i);
  		status = -EINVAL;
  		goto bail;
  	}
  	if (!(osb->sb->s_flags & MS_RDONLY) &&
  	    (i = OCFS2_HAS_RO_COMPAT_FEATURE(osb->sb, ~OCFS2_FEATURE_RO_COMPAT_SUPP))) {
  		mlog(ML_ERROR, "couldn't mount RDWR because of "
  		     "unsupported optional features (%x).
  ", i);
  		status = -EINVAL;
  		goto bail;
  	}

  	if (ocfs2_clusterinfo_valid(osb)) {
  		osb->osb_stackflags =
  			OCFS2_RAW_SB(di)->s_cluster_info.ci_stackflags;

  		memcpy(osb->osb_cluster_stack,
  		       OCFS2_RAW_SB(di)->s_cluster_info.ci_stack,
  		       OCFS2_STACK_LABEL_LEN);
  		osb->osb_cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';
  		if (strlen(osb->osb_cluster_stack) != OCFS2_STACK_LABEL_LEN) {
  			mlog(ML_ERROR,
  			     "couldn't mount because of an invalid "
  			     "cluster stack label (%s) 
  ",
  			     osb->osb_cluster_stack);
  			status = -EINVAL;
  			goto bail;
  		}
  	} else {
  		/* The empty string is identical with classic tools that
  		 * don't know about s_cluster_info. */
  		osb->osb_cluster_stack[0] = '\0';
  	}

  	get_random_bytes(&osb->s_next_generation, sizeof(u32));
  
  	/* FIXME
  	 * This should be done in ocfs2_journal_init(), but unknown
  	 * ordering issues will cause the filesystem to crash.
  	 * If anyone wants to figure out what part of the code
  	 * refers to osb->journal before ocfs2_journal_init() is run,
  	 * be my guest.
  	 */
  	/* initialize our journal structure */

  	journal = kzalloc(sizeof(struct ocfs2_journal), GFP_KERNEL);

  	if (!journal) {
  		mlog(ML_ERROR, "unable to alloc journal
  ");
  		status = -ENOMEM;
  		goto bail;
  	}
  	osb->journal = journal;
  	journal->j_osb = osb;
  
  	atomic_set(&journal->j_num_trans, 0);
  	init_rwsem(&journal->j_trans_barrier);
  	init_waitqueue_head(&journal->j_checkpointed);
  	spin_lock_init(&journal->j_lock);
  	journal->j_trans_id = (unsigned long) 1;
  	INIT_LIST_HEAD(&journal->j_la_cleanups);

  	INIT_WORK(&journal->j_recovery_work, ocfs2_complete_recovery);

  	journal->j_state = OCFS2_JOURNAL_FREE;

  	INIT_WORK(&osb->dentry_lock_work, ocfs2_drop_dl_inodes);
  	osb->dentry_lock_list = NULL;

  	/* get some pseudo constants for clustersize bits */
  	osb->s_clustersize_bits =
  		le32_to_cpu(di->id2.i_super.s_clustersize_bits);
  	osb->s_clustersize = 1 << osb->s_clustersize_bits;

  
  	if (osb->s_clustersize < OCFS2_MIN_CLUSTERSIZE ||
  	    osb->s_clustersize > OCFS2_MAX_CLUSTERSIZE) {
  		mlog(ML_ERROR, "Volume has invalid cluster size (%d)
  ",
  		     osb->s_clustersize);
  		status = -EINVAL;
  		goto bail;
  	}

  	total_blocks = ocfs2_clusters_to_blocks(osb->sb,
  						le32_to_cpu(di->i_clusters));
  
  	status = generic_check_addressable(osb->sb->s_blocksize_bits,
  					   total_blocks);
  	if (status) {
  		mlog(ML_ERROR, "Volume too large "
  		     "to mount safely on this system");
  		status = -EFBIG;

  		goto bail;
  	}
  
  	if (ocfs2_setup_osb_uuid(osb, di->id2.i_super.s_uuid,
  				 sizeof(di->id2.i_super.s_uuid))) {
  		mlog(ML_ERROR, "Out of memory trying to setup our uuid.
  ");
  		status = -ENOMEM;
  		goto bail;
  	}

  	memcpy(&uuid_net_key, di->id2.i_super.s_uuid, sizeof(uuid_net_key));

  
  	strncpy(osb->vol_label, di->id2.i_super.s_label, 63);
  	osb->vol_label[63] = '\0';
  	osb->root_blkno = le64_to_cpu(di->id2.i_super.s_root_blkno);
  	osb->system_dir_blkno = le64_to_cpu(di->id2.i_super.s_system_dir_blkno);
  	osb->first_cluster_group_blkno =
  		le64_to_cpu(di->id2.i_super.s_first_cluster_group);
  	osb->fs_generation = le32_to_cpu(di->i_fs_generation);

  	osb->uuid_hash = le32_to_cpu(di->id2.i_super.s_uuid_hash);

  	trace_ocfs2_initialize_super(osb->vol_label, osb->uuid_str,
  				     (unsigned long long)osb->root_blkno,
  				     (unsigned long long)osb->system_dir_blkno,
  				     osb->s_clustersize_bits);

  
  	osb->osb_dlm_debug = ocfs2_new_dlm_debug();
  	if (!osb->osb_dlm_debug) {
  		status = -ENOMEM;
  		mlog_errno(status);
  		goto bail;
  	}
  
  	atomic_set(&osb->vol_state, VOLUME_INIT);
  
  	/* load root, system_dir, and all global system inodes */
  	status = ocfs2_init_global_system_inodes(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto bail;
  	}
  
  	/*
  	 * global bitmap
  	 */
  	inode = ocfs2_get_system_file_inode(osb, GLOBAL_BITMAP_SYSTEM_INODE,
  					    OCFS2_INVALID_SLOT);
  	if (!inode) {
  		status = -EINVAL;
  		mlog_errno(status);
  		goto bail;
  	}
  
  	osb->bitmap_blkno = OCFS2_I(inode)->ip_blkno;

  	osb->osb_clusters_at_boot = OCFS2_I(inode)->ip_clusters;

  	iput(inode);

  	osb->bitmap_cpg = ocfs2_group_bitmap_size(sb, 0,
  				 osb->s_feature_incompat) * 8;

  
  	status = ocfs2_init_slot_info(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto bail;
  	}

  	cleancache_init_shared_fs((char *)&di->id2.i_super.s_uuid, sb);

  bail:

  	return status;
  }
  
  /*
   * will return: -EAGAIN if it is ok to keep searching for superblocks
   *              -EINVAL if there is a bad superblock
   *              0 on success
   */
  static int ocfs2_verify_volume(struct ocfs2_dinode *di,
  			       struct buffer_head *bh,

  			       u32 blksz,
  			       struct ocfs2_blockcheck_stats *stats)

  {
  	int status = -EAGAIN;

  	if (memcmp(di->i_signature, OCFS2_SUPER_BLOCK_SIGNATURE,
  		   strlen(OCFS2_SUPER_BLOCK_SIGNATURE)) == 0) {

  		/* We have to do a raw check of the feature here */
  		if (le32_to_cpu(di->id2.i_super.s_feature_incompat) &
  		    OCFS2_FEATURE_INCOMPAT_META_ECC) {
  			status = ocfs2_block_check_validate(bh->b_data,
  							    bh->b_size,

  							    &di->i_check,
  							    stats);

  			if (status)
  				goto out;
  		}

  		status = -EINVAL;
  		if ((1 << le32_to_cpu(di->id2.i_super.s_blocksize_bits)) != blksz) {
  			mlog(ML_ERROR, "found superblock with incorrect block "
  			     "size: found %u, should be %u
  ",
  			     1 << le32_to_cpu(di->id2.i_super.s_blocksize_bits),
  			       blksz);
  		} else if (le16_to_cpu(di->id2.i_super.s_major_rev_level) !=
  			   OCFS2_MAJOR_REV_LEVEL ||
  			   le16_to_cpu(di->id2.i_super.s_minor_rev_level) !=
  			   OCFS2_MINOR_REV_LEVEL) {
  			mlog(ML_ERROR, "found superblock with bad version: "
  			     "found %u.%u, should be %u.%u
  ",
  			     le16_to_cpu(di->id2.i_super.s_major_rev_level),
  			     le16_to_cpu(di->id2.i_super.s_minor_rev_level),
  			     OCFS2_MAJOR_REV_LEVEL,
  			     OCFS2_MINOR_REV_LEVEL);
  		} else if (bh->b_blocknr != le64_to_cpu(di->i_blkno)) {
  			mlog(ML_ERROR, "bad block number on superblock: "

  			     "found %llu, should be %llu
  ",

  			     (unsigned long long)le64_to_cpu(di->i_blkno),

  			     (unsigned long long)bh->b_blocknr);

  		} else if (le32_to_cpu(di->id2.i_super.s_clustersize_bits) < 12 ||
  			    le32_to_cpu(di->id2.i_super.s_clustersize_bits) > 20) {
  			mlog(ML_ERROR, "bad cluster size found: %u
  ",
  			     1 << le32_to_cpu(di->id2.i_super.s_clustersize_bits));
  		} else if (!le64_to_cpu(di->id2.i_super.s_root_blkno)) {
  			mlog(ML_ERROR, "bad root_blkno: 0
  ");
  		} else if (!le64_to_cpu(di->id2.i_super.s_system_dir_blkno)) {
  			mlog(ML_ERROR, "bad system_dir_blkno: 0
  ");
  		} else if (le16_to_cpu(di->id2.i_super.s_max_slots) > OCFS2_MAX_SLOTS) {
  			mlog(ML_ERROR,
  			     "Superblock slots found greater than file system "
  			     "maximum: found %u, max %u
  ",
  			     le16_to_cpu(di->id2.i_super.s_max_slots),
  			     OCFS2_MAX_SLOTS);
  		} else {
  			/* found it! */
  			status = 0;
  		}
  	}

  out:

  	if (status && status != -EAGAIN)
  		mlog_errno(status);

  	return status;
  }
  
  static int ocfs2_check_volume(struct ocfs2_super *osb)
  {

  	int status;

  	int dirty;

  	int local;

  	struct ocfs2_dinode *local_alloc = NULL; /* only used if we
  						  * recover
  						  * ourselves. */

  	/* Init our journal object. */
  	status = ocfs2_journal_init(osb->journal, &dirty);
  	if (status < 0) {
  		mlog(ML_ERROR, "Could not initialize journal!
  ");
  		goto finally;
  	}

  	/* Now that journal has been initialized, check to make sure
  	   entire volume is addressable. */
  	status = ocfs2_journal_addressable(osb);
  	if (status)
  		goto finally;

  	/* If the journal was unmounted cleanly then we don't want to
  	 * recover anything. Otherwise, journal_load will do that
  	 * dirty work for us :) */
  	if (!dirty) {
  		status = ocfs2_journal_wipe(osb->journal, 0);
  		if (status < 0) {
  			mlog_errno(status);
  			goto finally;
  		}
  	} else {

  		printk(KERN_NOTICE "ocfs2: File system on device (%s) was not "
  		       "unmounted cleanly, recovering it.
  ", osb->dev_str);

  	}

  	local = ocfs2_mount_local(osb);

  	/* will play back anything left in the journal. */

  	status = ocfs2_journal_load(osb->journal, local, dirty);

  	if (status < 0) {
  		mlog(ML_ERROR, "ocfs2 journal load failed! %d
  ", status);
  		goto finally;
  	}

  
  	if (dirty) {
  		/* recover my local alloc if we didn't unmount cleanly. */
  		status = ocfs2_begin_local_alloc_recovery(osb,
  							  osb->slot_num,
  							  &local_alloc);
  		if (status < 0) {
  			mlog_errno(status);
  			goto finally;
  		}
  		/* we complete the recovery process after we've marked
  		 * ourselves as mounted. */
  	}

  	status = ocfs2_load_local_alloc(osb);
  	if (status < 0) {
  		mlog_errno(status);
  		goto finally;
  	}
  
  	if (dirty) {
  		/* Recovery will be completed after we've mounted the
  		 * rest of the volume. */
  		osb->dirty = 1;
  		osb->local_alloc_copy = local_alloc;
  		local_alloc = NULL;
  	}
  
  	/* go through each journal, trylock it and if you get the
  	 * lock, and it's marked as dirty, set the bit in the recover
  	 * map and launch a recovery thread for it. */
  	status = ocfs2_mark_dead_nodes(osb);

  	if (status < 0) {
  		mlog_errno(status);
  		goto finally;
  	}
  
  	status = ocfs2_compute_replay_slots(osb);

  	if (status < 0)
  		mlog_errno(status);
  
  finally:
  	if (local_alloc)
  		kfree(local_alloc);

  	if (status)
  		mlog_errno(status);

  	return status;
  }
  
  /*
   * The routine gets called from dismount or close whenever a dismount on
   * volume is requested and the osb open count becomes 1.
   * It will remove the osb from the global list and also free up all the
   * initialized resources and fileobject.
   */
  static void ocfs2_delete_osb(struct ocfs2_super *osb)
  {

  	/* This function assumes that the caller has the main osb resource */

  	ocfs2_free_slot_info(osb);

  	kfree(osb->osb_orphan_wipes);

  	kfree(osb->slot_recovery_generations);

  	/* FIXME
  	 * This belongs in journal shutdown, but because we have to

  	 * allocate osb->journal at the start of ocfs2_initialize_osb(),

  	 * we free it here.
  	 */
  	kfree(osb->journal);
  	if (osb->local_alloc_copy)
  		kfree(osb->local_alloc_copy);
  	kfree(osb->uuid_str);
  	ocfs2_put_dlm_debug(osb->osb_dlm_debug);
  	memset(osb, 0, sizeof(struct ocfs2_super));

  }
  
  /* Put OCFS2 into a readonly state, or (if the user specifies it),
   * panic(). We do not support continue-on-error operation. */
  static void ocfs2_handle_error(struct super_block *sb)
  {
  	struct ocfs2_super *osb = OCFS2_SB(sb);
  
  	if (osb->s_mount_opt & OCFS2_MOUNT_ERRORS_PANIC)
  		panic("OCFS2: (device %s): panic forced after error
  ",
  		      sb->s_id);
  
  	ocfs2_set_osb_flag(osb, OCFS2_OSB_ERROR_FS);
  
  	if (sb->s_flags & MS_RDONLY &&
  	    (ocfs2_is_soft_readonly(osb) ||
  	     ocfs2_is_hard_readonly(osb)))
  		return;
  
  	printk(KERN_CRIT "File system is now read-only due to the potential "
  	       "of on-disk corruption. Please run fsck.ocfs2 once the file "
  	       "system is unmounted.
  ");
  	sb->s_flags |= MS_RDONLY;
  	ocfs2_set_ro_flag(osb, 0);
  }
  
  static char error_buf[1024];
  
  void __ocfs2_error(struct super_block *sb,
  		   const char *function,
  		   const char *fmt, ...)
  {
  	va_list args;
  
  	va_start(args, fmt);

  	vsnprintf(error_buf, sizeof(error_buf), fmt, args);

  	va_end(args);
  
  	/* Not using mlog here because we want to show the actual
  	 * function the error came from. */
  	printk(KERN_CRIT "OCFS2: ERROR (device %s): %s: %s
  ",
  	       sb->s_id, function, error_buf);
  
  	ocfs2_handle_error(sb);
  }
  
  /* Handle critical errors. This is intentionally more drastic than
   * ocfs2_handle_error, so we only use for things like journal errors,
   * etc. */
  void __ocfs2_abort(struct super_block* sb,
  		   const char *function,
  		   const char *fmt, ...)
  {
  	va_list args;
  
  	va_start(args, fmt);

  	vsnprintf(error_buf, sizeof(error_buf), fmt, args);

  	va_end(args);
  
  	printk(KERN_CRIT "OCFS2: abort (device %s): %s: %s
  ",
  	       sb->s_id, function, error_buf);
  
  	/* We don't have the cluster support yet to go straight to
  	 * hard readonly in here. Until then, we want to keep
  	 * ocfs2_abort() so that we can at least mark critical
  	 * errors.
  	 *
  	 * TODO: This should abort the journal and alert other nodes
  	 * that our slot needs recovery. */
  
  	/* Force a panic(). This stinks, but it's better than letting
  	 * things continue without having a proper hard readonly
  	 * here. */

  	if (!ocfs2_mount_local(OCFS2_SB(sb)))
  		OCFS2_SB(sb)->s_mount_opt |= OCFS2_MOUNT_ERRORS_PANIC;

  	ocfs2_handle_error(sb);
  }

  /*
   * Void signal blockers, because in-kernel sigprocmask() only fails
   * when SIG_* is wrong.
   */
  void ocfs2_block_signals(sigset_t *oldset)
  {
  	int rc;
  	sigset_t blocked;
  
  	sigfillset(&blocked);
  	rc = sigprocmask(SIG_BLOCK, &blocked, oldset);
  	BUG_ON(rc);
  }
  
  void ocfs2_unblock_signals(sigset_t *oldset)
  {
  	int rc = sigprocmask(SIG_SETMASK, oldset, NULL);
  	BUG_ON(rc);
  }

  module_init(ocfs2_init);
  module_exit(ocfs2_exit);