path: root/fs/xfs/quota/xfs_qm_syscalls.c

/*
 * Copyright (c) 2000-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <linux/capability.h>

#include "xfs.h"
#include "xfs_fs.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_trans.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_alloc.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_inode.h"
#include "xfs_itable.h"
#include "xfs_bmap.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_attr.h"
#include "xfs_buf_item.h"
#include "xfs_utils.h"
#include "xfs_qm.h"
#include "xfs_trace.h"

STATIC int	xfs_qm_log_quotaoff(xfs_mount_t *, xfs_qoff_logitem_t **, uint);
STATIC int	xfs_qm_log_quotaoff_end(xfs_mount_t *, xfs_qoff_logitem_t *,
					uint);
STATIC uint	xfs_qm_export_flags(uint);
STATIC uint	xfs_qm_export_qtype_flags(uint);
STATIC void	xfs_qm_export_dquot(xfs_mount_t *, xfs_disk_dquot_t *,
					fs_disk_quota_t *);


/*
 * Turn off quota accounting and/or enforcement for all udquots and/or
 * gdquots. Called only at unmount time.
 *
 * This assumes that there are no dquots of this file system cached
 * incore, and modifies the ondisk dquot directly. Therefore, for example,
 * it is an error to call this twice, without purging the cache.
 */
int
xfs_qm_scall_quotaoff(
	xfs_mount_t		*mp,
	uint			flags)
{
	struct xfs_quotainfo	*q = mp->m_quotainfo;
	uint			dqtype;
	int			error;
	uint			inactivate_flags;
	xfs_qoff_logitem_t	*qoffstart;
	int			nculprits;

	/*
	 * No file system can have quotas enabled on disk but not in core.
	 * Note that quota utilities (like quotaoff) _expect_
	 * errno == EEXIST here.
	 */
	if ((mp->m_qflags & flags) == 0)
		return XFS_ERROR(EEXIST);
	error = 0;

	flags &= (XFS_ALL_QUOTA_ACCT | XFS_ALL_QUOTA_ENFD);

	/*
	 * We don't want to deal with two quotaoffs messing up each other,
	 * so we're going to serialize it. quotaoff isn't exactly a performance
	 * critical thing.
	 * If quotaoff, then we must be dealing with the root filesystem.
	 */
	ASSERT(q);
	mutex_lock(&q->qi_quotaofflock);

	/*
	 * If we're just turning off quota enforcement, change mp and go.
	 */
	if ((flags & XFS_ALL_QUOTA_ACCT) == 0) {
		mp->m_qflags &= ~(flags);

		spin_lock(&mp->m_sb_lock);
		mp->m_sb.sb_qflags = mp->m_qflags;
		spin_unlock(&mp->m_sb_lock);
		mutex_unlock(&q->qi_quotaofflock);

		/* XXX what to do if error ? Revert back to old vals incore ? */
		error = xfs_qm_write_sb_changes(mp, XFS_SB_QFLAGS);
		return (error);
	}

	dqtype = 0;
	inactivate_flags = 0;
	/*
	 * If accounting is off, we must turn enforcement off, clear the
	 * quota 'CHKD' certificate to make it known that we have to
	 * do a quotacheck the next time this quota is turned on.
	 */
	if (flags & XFS_UQUOTA_ACCT) {
		dqtype