/*
 *  linux/fs/ext3/super.c
 *
 * Copyright (C) 1992, 1993, 1994, 1995
 * Remy Card (card@masi.ibp.fr)
 * Laboratoire MASI - Institut Blaise Pascal
 * Universite Pierre et Marie Curie (Paris VI)
 *
 *  from
 *
 *  linux/fs/minix/inode.c
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  Big-endian to little-endian byte-swapping/bitmaps by
 *        David S. Miller (davem@caip.rutgers.edu), 1995
 */

#include <linux/module.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/jbd.h>
#include <linux/ext3_fs.h>
#include <linux/ext3_jbd.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/parser.h>
#include <linux/smp_lock.h>
#include <linux/buffer_head.h>
#include <linux/exportfs.h>
#include <linux/vfs.h>
#include <linux/random.h>
#include <linux/mount.h>
#include <linux/namei.h>
#include <linux/quotaops.h>
#include <linux/seq_file.h>
#include <linux/log2.h>

#include <asm/uaccess.h>

#include "xattr.h"
#include "acl.h"
#include "namei.h"

static int ext3_load_journal(struct super_block *, struct ext3_super_block *,
			     unsigned long journal_devnum);
static int ext3_create_journal(struct super_block *, struct ext3_super_block *,
			       unsigned int);
static void ext3_commit_super (struct super_block * sb,
			       struct ext3_super_block * es,
			       int sync);
static void ext3_mark_recovery_complete(struct super_block * sb,
					struct ext3_super_block * es);
static void ext3_clear_journal_err(struct super_block * sb,
				   struct ext3_super_block * es);
static int ext3_sync_fs(struct super_block *sb, int wait);
static const char *ext3_decode_error(struct super_block * sb, int errno,
				     char nbuf[16]);
static int ext3_remount (struct super_block * sb, int * flags, char * data);
static int ext3_statfs (struct dentry * dentry, struct kstatfs * buf);
static void ext3_unlockfs(struct super_block *sb);
static void ext3_write_super (struct super_block * sb);
static void ext3_write_super_lockfs(struct super_block *sb);

/*
 * Wrappers for journal_start/end.
 *
 * The only special thing we need to do here is to make sure that all
 * journal_end calls result in the superblock being marked dirty, so
 * that sync() will call the filesystem's write_super callback if
 * appropriate.
 */
handle_t *ext3_journal_start_sb(struct super_block *sb, int nblocks)
{
	journal_t *journal;

	if (sb->s_flags & MS_RDONLY)
		return ERR_PTR(-EROFS);

	/* Special case here: if the journal has aborted behind our
	 * backs (eg. EIO in the commit thread), then we still need to
	 * take the FS itself readonly cleanly. */
	journal = EXT3_SB(sb)->s_journal;
	if (is_journal_aborted(journal)) {
		ext3_abort(sb, __FUNCTION__,
			   "Detected aborted journal");
		return ERR_PTR(-EROFS);
	}

	return journal_start(journal, nblocks);
}

/*
 * The only special thing we need to do here is to make sure that all
 * journal_stop calls result in the superblock being marked dirty, so
 * that sync() will call the filesystem's write_super callback if
 * appropriate.
 */
int __ext3_journal_stop(const char *where, handle_t *handle)
{
	struct super_block *sb;
	int err;
	int rc;

	sb = handle->h_transaction->t_journal->j_private;
	err = handle->h_err;
	rc = journal_stop(handle);

	if (!err)
		err = rc;
	if (err)
		__ext3_std_error(sb, where, err);
	return err;
}

void ext3_journal_abort_handle(const char *caller, const char *err_fn,
		struct buffer_head *bh, handle_t *handle, int err)
{
	char nbuf[16];
	const char *errstr = ext3_decode_error(NULL, err, nbuf);

	if (bh)
		BUFFER_TRACE(bh, "abort");

	if (!handle->h_err)
		handle->h_err = err;

	if (is_handle_aborted(handle))
		return;

	printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
	       caller, errstr, err_fn);

	journal_abort_handle(handle);
}

/* Deal with the reporting of failure conditions on a filesystem such as
 * inconsistencies detected or read IO failures.
 *
 * On ext2, we can store the error state of the filesystem in the
 * superblock.  That is not possible on ext3, because we may have other
 * write ordering constraints on the superblock which prevent us from
 * writing it out straight away; and given that the journal is about to
 * be aborted, we can't rely on the current, or future, transactions to
 * write out the superblock safely.
 *
 * We'll just use the journal_abort() error code to record an error in
 * the journal instead.  On recovery, the journal will compain about
 * that error until we've noted it down and cleared it.
 */

static void ext3_handle_error(struct super_block *sb)
{
	struct ext3_super_block *es = EXT3_SB(sb)->s_es;

	EXT3_SB(sb)->s_mount_state |= EXT3_ERROR_FS;
	es->s_state |= cpu_to_le16(EXT3_ERROR_FS);

	if (sb->s_flags & MS_RDONLY)
		return;

	if (!test_opt (sb, ERRORS_CONT)) {
		journal_t *journal = EXT3_SB(sb)->s_journal;

		EXT3_SB(sb)->s_mount_opt |= EXT3_MOUNT_ABORT;
		if (journal)
			journal_abort(journal, -EIO);
	}
	if (test_opt (sb, ERRORS_RO)) {
		printk (KERN_CRIT "Remounting filesystem read-only\n");
		sb->s_flags |= MS_RDONLY;
	}
	ext3_commit_super(sb, es, 1);
	if (test_opt(sb, ERRORS_PANIC))
		panic("EXT3-fs (device %s): panic forced after error\n",
			sb->s_id);
}

void ext3_error (struct super_block * sb, const char * function,
		 const char * fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	printk(KERN_CRIT "EXT3-fs error (device %s): %s: ",sb->s_id, function);
	vprintk(fmt, args);
	printk("\n");
	va_end(args);

	ext3_handle_error(sb);
}

static const char *ext3_decode_error(struct super_block * sb, int errno,
				     char nbuf[16])
{
	char *errstr = NULL;

	switch (errno) {
	case -EIO:
		errstr = "IO failure";
		break;
	case -ENOMEM:
		errstr = "Out of memory";
		break;
	case -EROFS:
		if (!sb || EXT3_SB(sb)->s_journal->j_flags & JFS_ABORT)
			errstr = "Journal has aborted";
		else
			errstr = "Readonly filesystem";
		break;
	default:
		/* If the caller passed in an extra buffer for unknown
		 * errors, textualise them now.  Else we just return
		 * NULL. */
		if (nbuf) {
			/* Check for truncated error codes... */
			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
				errstr = nbuf;
		}
		break;
	}

	return errstr;
}

/* __ext3_std_error decodes expected errors from journaling functions
 * automatically and invokes the appropriate error response.  */

void __ext3_std_error (struct super_block * sb, const char * function,
		       int errno)
{
	char nbuf[16];
	const char *errstr;

	/* Special case: if the error is EROFS, and we're not already
	 * inside a transaction, then there's really no point in logging
	 * an error. */
	if (errno == -EROFS && journal_current_handle() == NULL &&
	    (sb->s_flags & MS_RDONLY))
		return;

	errstr = ext3_decode_error(sb, errno, nbuf);
	printk (KERN_CRIT "EXT3-fs error (device %s) in %s: %s\n",
		sb->s_id, function, errstr);

	ext3_handle_error(sb);
}

/*
 * ext3_abort is a much stronger failure handler than ext3_error.  The
 * abort function may be used to deal with unrecoverable failures such
 * as journal IO errors or ENOMEM at a critical moment in log management.
 *
 * We unconditionally force the filesystem into an ABORT|READONLY state,
 * unless the error response on the fs has been set to panic in which
 * case we take the easy way out and panic immediately.
 */

void ext3_abort (struct super_block * sb, const char * function,
		 const char * fmt, ...)
{
	va_list args;

	printk (KERN_CRIT "ext3_abort called.\n");

	va_start(args, fmt);
	printk(KERN_CRIT "EXT3-fs error (device %s): %s: ",sb->s_id, function);
	vprintk(fmt, args);
	printk("\n");
	va_end(args);

	if (test_opt(sb, ERRORS_PANIC))
		panic("EXT3-fs panic from previous error\n");

	if (sb->s_flags & MS_RDONLY)
		return;

	printk(KERN_CRIT "Remounting filesystem read-only\n");
	EXT3_SB(sb)->s_mount_state |= EXT3_ERROR_FS;
	sb->s_flags |= MS_RDONLY;
	EXT3_SB(sb)->s_mount_opt |= EXT3_MOUNT_ABORT;
	journal_abort(EXT3_SB(sb)->s_journal, -EIO);
}

void ext3_warning (struct super_block * sb, const char * function,
		   const char * fmt, ...)
{
	va_list args;

	va_start(args, fmt);
	printk(KERN_WARNING "EXT3-fs warning (device %s): %s: ",
	       sb->s_id, function);
	vprintk(fmt, args);
	printk("\n");
	va_end(args);
}

void ext3_update_dynamic_rev(struct super_block *sb)
{
	struct ext3_super_block *es = EXT3_SB(sb)->s_es;

	if (le32_to_cpu(es->s_rev_level) > EXT3_GOOD_OLD_REV)
		return;

	ext3_warning(sb, __FUNCTION__,
		     "updating to rev %d because of new feature flag, "
		     "running e2fsck is recommended",
		     EXT3_DYNAMIC_REV);

	es->s_first_ino = cpu_to_le32(EXT3_GOOD_OLD_FIRST_INO);
	es->s_inode_size = cpu_to_le16(EXT3_GOOD_OLD_INODE_SIZE);
	es->s_rev_level = cpu_to_le32(EXT3_DYNAMIC_REV);
	/* leave es->s_feature_*compat flags alone */
	/* es->s_uuid will be set by e2fsck if empty */

	/*
	 * The rest of the superblock fields should be zero, and if not it
	 * means they are likely already in use, so leave them alone.  We
	 * can leave it up to e2fsck to clean up any inconsistencies there.
	 */
}

/*
 * Open the external journal device
 */
static struct block_device *ext3_blkdev_get(dev_t dev)
{
	struct block_device *bdev;
	char b[BDEVNAME_SIZE];

	bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
	if (IS_ERR(bdev))
		goto fail;
	return bdev;

fail:
	printk(KERN_ERR "EXT3: failed to open journal device %s: %ld\n",
			__bdevname(dev, b), PTR_ERR(bdev));
	return NULL;
}

/*
 * Release the journal device
 */
static int ext3_blkdev_put(struct block_device *bdev)
{
	bd_release(bdev);
	return blkdev_put(bdev);
}

static int ext3_blkdev_remove(struct ext3_sb_info *sbi)
{
	struct block_device *bdev;
	int ret = -ENODEV;

	bdev = sbi->journal_bdev;
	if (bdev) {
		ret = ext3_blkdev_put(bdev);
		sbi->journal_bdev = NULL;
	}
	return ret;
}

static inline struct inode *orphan_list_entry(struct list_head *l)
{
	return &list_entry(l, struct ext3_inode_info, i_orphan)->vfs_inode;
}

static void dump_orphan_list(struct super_block *sb, struct ext3_sb_info *sbi)
{
	struct list_head *l;

	printk(KERN_ERR "sb orphan head is %d\n",
	       le32_to_cpu(sbi->s_es->s_last_orphan));

	printk(KERN_ERR "sb_info orphan list:\n");
	list_for_each(l, &sbi->s_orphan) {
		struct inode *inode = orphan_list_entry(l);
		printk(KERN_ERR "  "
		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
		       inode->i_sb->s_id, inode->i_ino, inode,
		       inode->i_mode, inode->i_nlink,
		       NEXT_ORPHAN(inode));
	}
}

static void ext3_put_super (struct super_block * sb)
{
	struct ext3_sb_info *sbi = EXT3_SB(sb);
	struct ext3_super_block *es = sbi->s_es;
	int i;

	ext3_xattr_put_super(sb);
	journal_destroy(sbi->s_journal);
	if (!(sb->s_flags & MS_RDONLY)) {
		EXT3_CLEAR_INCOMPAT_FEATURE(sb, EXT3_FEATURE_INCOMPAT_RECOVER);
		es->s_state = cpu_to_le16(sbi->s_mount_state);
		BUFFER_TRACE(sbi->s_sbh, "marking dirty");
		mark_buffer_dirty(sbi->s_sbh);
		ext3_commit_super(sb, es, 1);
	}

	for (i = 0; i < sbi->s_gdb_count; i++)
		brelse(sbi->s_group_desc[i]);
	kfree(sbi->s_group_desc);
	percpu_counter_destroy(&sbi->s_freeblocks_counter);
	percpu_counter_destroy(&sbi->s_freeinodes_counter);
	percpu_counter_destroy(&sbi->s_dirs_counter);
	brelse(sbi->s_sbh);
#ifdef CONFIG_QUOTA
	for (i = 0; i < MAXQUOTAS; i++)
		kfree(sbi->s_qf_names[i]);
#endif

	/* Debugging code just in case the in-memory inode orphan list
	 * isn't empty.  The on-disk one can be non-empty if we've
	 * detected an error and taken the fs readonly, but the
	 * in-memory list had better be clean by this point. */
	if (!list_empty(&sbi->s_orphan))
		dump_orphan_list(sb, sbi);
	J_ASSERT(list_empty(&sbi->s_orphan));

	invalidate_bdev(sb->s_bdev);
	if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
		/*
		 * Invalidate the journal device's buffers.  We don't want them
		 * floating about in memory - the physical journal device may
		 * hotswapped, and it breaks the `ro-after' testing code.
		 */
		sync_blockdev(sbi->journal_bdev);
		invalidate_bdev(sbi->journal_bdev);
		ext3_blkdev_remove(sbi);
	}
	sb->s_fs_info = NULL;
	kfree(sbi);
	return;
}

static struct kmem_cache *ext3_inode_cachep;

/*
 * Called inside transaction, so use GFP_NOFS
 */
static struct inode *ext3_alloc_inode(struct super_block *sb)
{
	struct ext3_inode_info *ei;

	ei = kmem_cache_alloc(ext3_inode_cachep, GFP_NOFS);
	if (!ei)
		return NULL;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
	ei->i_acl = EXT3_ACL_NOT_CACHED;
	ei->i_default_acl = EXT3_ACL_NOT_CACHED;
#endif
	ei->i_block_alloc_info = NULL;
	ei->vfs_inode.i_version = 1;
	return &ei->vfs_inode;
}

static void ext3_destroy_inode(struct inode *inode)
{
	if (!list_empty(&(EXT3_I(inode)->i_orphan))) {
		printk("EXT3 Inode %p: orphan list check failed!\n",
			EXT3_I(inode));
		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
				EXT3_I(inode), sizeof(struct ext3_inode_info),
				false);
		dump_stack();
	}
	kmem_cache_free(ext3_inode_cachep, EXT3_I(inode));
}

static void init_once(struct kmem_cache * cachep, void *foo)
{
	struct ext3_inode_info *ei = (struct ext3_inode_info *) foo;

	INIT_LIST_HEAD(&ei->i_orphan);
#ifdef CONFIG_EXT3_FS_XATTR
	init_rwsem(&ei->xattr_sem);
#endif
	mutex_init(&ei->truncate_mutex);
	inode_init_once(&ei->vfs_inode);
}

static int init_inodecache(void)
{
	ext3_inode_cachep = kmem_cache_create("ext3_inode_cache",
					     sizeof(struct ext3_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD),
					     init_once);
	if (ext3_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static void destroy_inodecache(void)
{
	kmem_cache_destroy(ext3_inode_cachep);
}

static void ext3_clear_inode(struct inode *inode)
{
	struct ext3_block_alloc_info *rsv = EXT3_I(inode)->i_block_alloc_info;
#ifdef CONFIG_EXT3_FS_POSIX_ACL
	if (EXT3_I(inode)->i_acl &&
			EXT3_I(inode)->i_acl != EXT3_ACL_NOT_CACHED) {
		posix_acl_release(EXT3_I(inode)->i_acl);
		EXT3_I(inode)->i_acl = EXT3_ACL_NOT_CACHED;
	}
	if (EXT3_I(inode)->i_default_acl &&
			EXT3_I(inode)->i_default_acl != EXT3_ACL_NOT_CACHED) {
		posix_acl_release(EXT3_I(inode)->i_default_acl);
		EXT3_I(inode)->i_default_acl = EXT3_ACL_NOT_CACHED;
	}
#endif
	ext3_discard_reservation(inode);
	EXT3_I(inode)->i_block_alloc_info = NULL;
	if (unlikely(rsv))
		kfree(rsv);
}

static inline void ext3_show_quota_options(struct seq_file *seq, struct super_block *sb)
{
#if defined(CONFIG_QUOTA)
	struct ext3_sb_info *sbi = EXT3_SB(sb);

	if (sbi->s_jquota_fmt)
		seq_printf(seq, ",jqfmt=%s",
		(sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold": "vfsv0");

	if (sbi->s_qf_names[USRQUOTA])
		seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);

	if (sbi->s_qf_names[GRPQUOTA])
		seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);

	if (sbi->s_mount_opt & EXT3_MOUNT_USRQUOTA)
		seq_puts(seq, ",usrquota");

	if (sbi->s_mount_opt & EXT3_MOUNT_GRPQUOTA)
		seq_puts(seq, ",grpquota");
#endif
}

/*
 * Show an option if
 *  - it's set to a non-default value OR
 *  - if the per-sb default is different from the global default
 */
static int ext3_show_options(struct seq_file *seq, struct vfsmount *vfs)
{
	struct super_block *sb = vfs->mnt_sb;
	struct ext3_sb_info *sbi = EXT3_SB(sb);
	struct ext3_super_block *es = sbi->s_es;
	unsigned long def_mount_opts;

	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);

	if (sbi->s_sb_block != 1)
		seq_printf(seq, ",sb=%lu", sbi->s_sb_block);
	if (test_opt(sb, MINIX_DF))
		seq_puts(seq, ",minixdf");
	if (test_opt(sb, GRPID))
		seq_puts(seq, ",grpid");
	if (!test_opt(sb, GRPID) && (def_mount_opts & EXT3_DEFM_BSDGROUPS))
		seq_puts(seq, ",nogrpid");
	if (sbi->s_resuid != EXT3_DEF_RESUID ||
	    le16_to_cpu(es->s_def_resuid) != EXT3_DEF_RESUID) {
		seq_printf(seq, ",resuid=%u", sbi->s_resuid);
	}
	if (sbi->s_resgid != EXT3_DEF_RESGID ||
	    le16_to_cpu(es->s_def_resgid) != EXT3_DEF_RESGID) {
		seq_printf(seq, ",resgid=%u", sbi->s_resgid);
	}
	if (test_opt(sb, ERRORS_CONT)) {
		int def_errors = le16_to_cpu(es->s_errors);

		if (def_errors == EXT3_ERRORS_PANIC ||
		    def_errors == EXT3_ERRORS_RO) {
			seq_puts(seq, ",errors=continue");
		}
	}
	if (test_opt(sb, ERRORS_RO))
		seq_puts(seq, ",errors=remount-ro");
	if (test_opt(sb, ERRORS_PANIC))
		seq_puts(seq, ",errors=panic");
	if (test_opt(sb, NO_UID32))
		seq_puts(seq, ",nouid32");
	if (test_opt(sb, DEBUG))
		seq_puts(seq, ",debug");
	if (test_opt(sb, OLDALLOC))
		seq_puts(seq, ",oldalloc");
#ifdef CONFIG_EXT3_FS_XATTR
	if (test_opt(sb, XATTR_USER))
		seq_puts(seq, ",user_xattr");
	if (!test_opt(sb, XATTR_USER) &&
	    (def_mount_opts & EXT3_DEFM_XATTR_USER)) {
		seq_puts(seq, ",nouser_xattr");
	}
#endif
#ifdef CONFIG_EXT3_FS_POSIX_ACL
	if (test_opt(sb, POSIX_ACL))
		seq_puts(seq, ",acl");
	if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT3_DEFM_ACL))
		seq_puts(seq, ",noacl");
#endif
	if (!test_opt(sb, RESERVATION))
		seq_puts(seq, ",noreservation");
	if (sbi->s_commit_interval) {
		seq_printf(seq, ",commit=%u",
			   (unsigned) (sbi->s_commit_interval / HZ));
	}
	if (test_opt(sb, BARRIER))
		seq_puts(seq, ",barrier=1");
	if (test_opt(sb, NOBH))
		seq_puts(seq, ",nobh");

	if (test_opt(sb, DATA_FLAGS) == EXT3_MOUNT_JOURNAL_DATA)
		seq_puts(seq, ",data=journal");
	else if (test_opt(sb, DATA_FLAGS) == EXT3_MOUNT_ORDERED_DATA)
		seq_puts(seq, ",data=ordered");
	else if (test_opt(sb, DATA_FLAGS) == EXT3_MOUNT_WRITEBACK_DATA)
		seq_puts(seq, ",data=writeback");

	ext3_show_quota_options(seq, sb);

	return 0;
}


static struct inode *ext3_nfs_get_inode(struct super_block *sb,
		u64 ino, u32 generation)
{
	struct inode *inode;

	if (ino < EXT3_FIRST_INO(sb) && ino != EXT3_ROOT_INO)
		return ERR_PTR(-ESTALE);
	if (ino > le32_to_cpu(EXT3_SB(sb)->s_es->s_inodes_count))
		return ERR_PTR(-ESTALE);

	/* iget isn't really right if the inode is currently unallocated!!
	 *
	 * ext3_read_inode will return a bad_inode if the inode had been
	 * deleted, so we should be safe.
	 *
	 * Currently we don't know the generation for parent directory, so
	 * a generation of 0 means "accept any"
	 */
	inode = iget(sb, ino);
	if (inode == NULL)
		return ERR_PTR(-ENOMEM);
	if (is_bad_inode(inode) ||
	    (generation && inode->i_generation != generation)) {
		iput(inode);
		return ERR_PTR(-ESTALE);
	}

	return inode;
}

static struct dentry *ext3_fh_to_dentry(struct super_block *sb, struct fid *fid,
		int fh_len, int fh_type)
{
	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
				    ext3_nfs_get_inode);
}

static struct dentry *ext3_fh_to_parent(struct super_block *sb, struct fid *fid,
		int fh_len, int fh_type)
{
	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
				    ext3_nfs_get_inode);
}

#ifdef CONFIG_QUOTA
#define QTYPE2NAME(t) ((t)==USRQUOTA?"user":"group")
#define QTYPE2MOPT(on, t) ((t)==USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))

static int ext3_dquot_initialize(struct inode *inode, int type);
static int ext3_dquot_drop(struct inode *inode);
static int ext3_write_dquot(struct dquot *dquot);
static int ext3_acquire_dquot(struct dquot *dquot);
static int ext3_release_dquot(struct dquot *dquot);
static int ext3_mark_dquot_dirty(struct dquot *dquot);
static int ext3_write_info(struct super_block *sb, int type);
static int ext3_quota_on(struct super_block *sb, int type, int format_id, char *path);
static int ext3_quota_on_mount(struct super_block *sb, int type);
static ssize_t ext3_quota_read(struct super_block *sb, int type, char *data,
			       size_t len, loff_t off);
static ssize_t ext3_quota_write(struct super_block *sb, int type,
				const char *data, size_t len, loff_t off);

static struct dquot_operations ext3_quota_operations = {
	.initialize	= ext3_dquot_initialize,
	.drop		= ext3_dquot_drop,
	.alloc_space	= dquot_alloc_space,
	.alloc_inode	= dquot_alloc_inode,
	.free_space	= dquot_free_space,
	.free_inode	= dquot_free_inode,
	.transfer	= dquot_transfer,
	.write_dquot	= ext3_write_dquot,
	.acquire_dquot	= ext3_acquire_dquot,
	.release_dquot	= ext3_release_dquot,
	.mark_dirty	= ext3_mark_dquot_dirty,
	.write_info	= ext3_write_info
};

static struct quotactl_ops ext3_qctl_operations = {
	.quota_on	= ext3_quota_on,
	.quota_off	= vfs_quota_off,
	.quota_sync	= vfs_quota_sync,
	.get_info	= vfs_get_dqinfo,
	.set_info	= vfs_set_dqinfo,
	.get_dqblk	= vfs_get_dqblk,
	.set_dqblk	= vfs_set_dqblk
};
#endif

static const struct super_operations ext3_sops = {
	.alloc_inode	= ext3_alloc_inode,
	.destroy_inode	= ext3_destroy_inode,
	.read_inode	= ext3_read_inode,
	.write_inode	= ext3_write_inode,
	.dirty_inode	= ext3_dirty_inode,
	.delete_inode	= ext3_delete_inode,
	.put_super	= ext3_put_super,
	.write_super	= ext3_write_super,
	.sync_fs	= ext3_sync_fs,
	.write_super_lockfs = ext3_write_super_lockfs,
	.unlockfs	= ext3_unlockfs,
	.statfs		= ext3_statfs,
	.remount_fs	= ext3_remount,
	.clear_inode	= ext3_clear_inode,
	.show_options	= ext3_show_options,
#ifdef CONFIG_QUOTA
	.quota_read	= ext3_quota_read,
	.quota_write	= ext3_quota_write,
#endif
};

static const struct export_operations ext3_export_ops = {
	.fh_to_dentry = ext3_fh_to_dentry,
	.fh_to_parent = ext3_fh_to_parent,
	.get_parent = ext3_get_parent,
};

enum {
	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
	Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov,
	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
	Opt_reservation, Opt_noreservation, Opt_noload, Opt_nobh, Opt_bh,
	Opt_commit, Opt_journal_update, Opt_journal_inum, Opt_journal_dev,
	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
	Opt_ignore, Opt_barrier, Opt_err, Opt_resize, Opt_usrquota,
	Opt_grpquota
};

static match_table_t tokens = {
	{Opt_bsd_df, "bsddf"},
	{Opt_minix_df, "minixdf"},
	{Opt_grpid, "grpid"},
	{Opt_grpid, "bsdgroups"},
	{Opt_nogrpid, "nogrpid"},
	{Opt_nogrpid, "sysvgroups"},
	{Opt_resgid, "resgid=%u"},
	{Opt_resuid, "resuid=%u"},
	{Opt_sb, "sb=%u"},
	{Opt_err_cont, "errors=continue"},
	{Opt_err_panic, "errors=panic"},
	{Opt_err_ro, "errors=remount-ro"},
	{Opt_nouid32, "nouid32"},
	{Opt_nocheck, "nocheck"},
	{Opt_nocheck, "check=none"},
	{Opt_debug, "debug"},
	{Opt_oldalloc, "oldalloc"},
	{Opt_orlov, "orlov"},
	{Opt_user_xattr, "user_xattr"},
	{Opt_nouser_xattr, "nouser_xattr"},
	{Opt_acl, "acl"},
	{Opt_noacl, "noacl"},
	{Opt_reservation, "reservation"},
	{Opt_noreservation, "noreservation"},
	{Opt_noload, "noload"},
	{Opt_nobh, "nobh"},
	{Opt_bh, "bh"},
	{Opt_commit, "commit=%u"},
	{Opt_journal_update, "journal=update"},
	{Opt_journal_inum, "journal=%u"},
	{Opt_journal_dev, "journal_dev=%u"},
	{Opt_abort, "abort"},
	{Opt_data_journal, "data=journal"},
	{Opt_data_ordered, "data=ordered"},
	{Opt_data_writeback, "data=writeback"},
	{Opt_offusrjquota, "usrjquota="},
	{Opt_usrjquota, "usrjquota=%s"},
	{Opt_offgrpjquota, "grpjquota="},
	{Opt_grpjquota, "grpjquota=%s"},
	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
	{Opt_grpquota, "grpquota"},
	{Opt_noquota, "noquota"},
	{Opt_quota, "quota"},
	{Opt_usrquota, "usrquota"},
	{Opt_barrier, "barrier=%u"},
	{Opt_err, NULL},
	{Opt_resize, "resize"},
};

static ext3_fsblk_t get_sb_block(void **data)
{
	ext3_fsblk_t	sb_block;
	char		*options = (char *) *data;

	if (!options || strncmp(options, "sb=", 3) != 0)
		return 1;	/* Default location */
	options += 3;
	/*todo: use simple_strtoll with >32bit ext3 */
	sb_block = simple_strtoul(options, &options, 0);
	if (*options && *options != ',') {
		printk("EXT3-fs: Invalid sb specification: %s\n",
		       (char *) *data);
		return 1;
	}
	if (*options == ',')
		options++;
	*data = (void *) options;
	return sb_block;
}

static int parse_options (char *options, struct super_block *sb,
			  unsigned int *inum, unsigned long *journal_devnum,
			  ext3_fsblk_t *n_blocks_count, int is_remount)
{
	struct ext3_sb_info *sbi = EXT3_SB(sb);
	char * p;
	substring_t args[MAX_OPT_ARGS];
	int data_opt = 0;
	int option;
#ifdef CONFIG_QUOTA
	int qtype;
	char *qname;
#endif

	if (!options)
		return 1;

	while ((p = strsep (&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case Opt_bsd_df:
			clear_opt (sbi->s_mount_opt, MINIX_DF);
			break;
		case Opt_minix_df:
			set_opt (sbi->s_mount_opt, MINIX_DF);
			break;
		case Opt_grpid:
			set_opt (sbi->s_mount_opt, GRPID);
			break;
		case Opt_nogrpid:
			clear_opt (sbi->s_mount_opt, GRPID);
			break;
		case Opt_resuid:
			if (match_int(&args[0], &option))
				return 0;
			sbi->s_resuid = option;
			break;
		case Opt_resgid:
			if (match_int(&args[0], &option))
				return 0;
			sbi->s_resgid = option;
			break;
		case Opt_sb:
			/* handled by get_sb_block() instead of here */
			/* *sb_block = match_int(&args[0]); */
			break;
		case Opt_err_panic:
			clear_opt (sbi->s_mount_opt, ERRORS_CONT);
			clear_opt (sbi->s_mount_opt, ERRORS_RO);
			set_opt (sbi->s_mount_opt, ERRORS_PANIC);
			break;
		case Opt_err_ro:
			clear_opt (sbi->s_mount_opt, ERRORS_CONT);
			clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
			set_opt (sbi->s_mount_opt, ERRORS_RO);
			break;
		case Opt_err_cont:
			clear_opt (sbi->s_mount_opt, ERRORS_RO);
			clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
			set_opt (sbi->s_mount_opt, ERRORS_CONT);
			break;
		case Opt_nouid32:
			set_opt (sbi->s_mount_opt, NO_UID32);
			break;
		case Opt_nocheck:
			clear_opt (sbi->s_mount_opt, CHECK);
			break;
		case Opt_debug:
			set_opt (sbi->s_mount_opt, DEBUG);
			break;
		case Opt_oldalloc:
			set_opt (sbi->s_mount_opt, OLDALLOC);
			break;
		case Opt_orlov:
			clear_opt (sbi->s_mount_opt, OLDALLOC);
			break;
#ifdef CONFIG_EXT3_FS_XATTR
		case Opt_user_xattr:
			set_opt (sbi->s_mount_opt, XATTR_USER);
			break;
		case Opt_nouser_xattr:
			clear_opt (sbi->s_mount_opt, XATTR_USER);
			break;
#else
		case Opt_user_xattr:
		case Opt_nouser_xattr:
			printk("EXT3 (no)user_xattr options not supported\n");
			break;
#endif
#ifdef CONFIG_EXT3_FS_POSIX_ACL
		case Opt_acl:
			set_opt(sbi->s_mount_opt, POSIX_ACL);
			break;
		case Opt_noacl:
			clear_opt(sbi->s_mount_opt, POSIX_ACL);
			break;
#else
		case Opt_acl:
		case Opt_noacl:
			printk("EXT3 (no)acl options not supported\n");
			break;
#endif
		case Opt_reservation:
			set_opt(sbi->s_mount_opt, RESERVATION);
			break;
		case Opt_noreservation:
			clear_opt(sbi->s_mount_opt, RESERVATION);
			break;
		case Opt_journal_update:
			/* @@@ FIXME */
			/* Eventually we will want to be able to create
			   a journal file here.  For now, only allow the
			   user to specify an existing inode to be the
			   journal file. */
			if (is_remount) {
				printk(KERN_ERR "EXT3-fs: cannot specify "
				       "journal on remount\n");
				return 0;
			}
			set_opt (sbi->s_mount_opt, UPDATE_JOURNAL);
			break;
		case Opt_journal_inum:
			if (is_remount) {
				printk(KERN_ERR "EXT3-fs: cannot specify "
				       "journal on remount\n");
				return 0;
			}
			if (match_int(&args[0], &option))
				return 0;
			*inum = option;
			break;
		case Opt_journal_dev:
			if (is_remount) {
				printk(KERN_ERR "EXT3-fs: cannot specify "
				       "journal on remount\n");
				return 0;
			}
			if (match_int(&args[0], &option))
				return 0;
			*journal_devnum = option;
			break;
		case Opt_noload:
			set_opt (sbi->s_mount_opt, NOLOAD);
			break;
		case Opt_commit:
			if (match_int(&args[0], &option))
				return 0;
			if (option < 0)
				return 0;
			if (option == 0)
				option = JBD_DEFAULT_MAX_COMMIT_AGE;
			sbi->s_commit_interval = HZ * option;
			break;
		case Opt_data_journal:
			data_opt = EXT3_MOUNT_JOURNAL_DATA;
			goto datacheck;
		case Opt_data_ordered:
			data_opt = EXT3_MOUNT_ORDERED_DATA;
			goto datacheck;
		case Opt_data_writeback:
			data_opt = EXT3_MOUNT_WRITEBACK_DATA;
		datacheck:
			if (is_remount) {
				if ((sbi->s_mount_opt & EXT3_MOUNT_DATA_FLAGS)
						!= data_opt) {
					printk(KERN_ERR
						"EXT3-fs: cannot change data "
						"mode on remount\n");
					return 0;
				}
			} else {
				sbi->s_mount_opt &= ~EXT3_MOUNT_DATA_FLAGS;
				sbi->s_mount_opt |= data_opt;
			}
			break;
#ifdef CONFIG_QUOTA
		case Opt_usrjquota:
			qtype = USRQUOTA;
			goto set_qf_name;
		case Opt_grpjquota:
			qtype = GRPQUOTA;
set_qf_name:
			if (sb_any_quota_enabled(sb)) {
				printk(KERN_ERR
					"EXT3-fs: Cannot change journalled "
					"quota options when quota turned on.\n");
				return 0;
			}
			qname = match_strdup(&args[0]);
			if (!qname) {
				printk(KERN_ERR
					"EXT3-fs: not enough memory for "
					"storing quotafile name.\n");
				return 0;
			}
			if (sbi->s_qf_names[qtype] &&
			    strcmp(sbi->s_qf_names[qtype], qname)) {
				printk(KERN_ERR
					"EXT3-fs: %s quota file already "
					"specified.\n", QTYPE2NAME(qtype));
				kfree(qname);
				return 0;
			}
			sbi->s_qf_names[qtype] = qname;
			if (strchr(sbi->s_qf_names[qtype], '/')) {
				printk(KERN_ERR
					"EXT3-fs: quotafile must be on "
					"filesystem root.\n");
				kfree(sbi->s_qf_names[qtype]);
				sbi->s_qf_names[qtype] = NULL;
				return 0;
			}