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_dir2.h"
#include "xfs_alloc.h"
#include "xfs_dmapi.h"
#include "xfs_quota.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_dir2_sf.h"
#include "xfs_attr_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_ialloc.h"
#include "xfs_itable.h"
#include "xfs_bmap.h"
#include "xfs_btree.h"
#include "xfs_rtalloc.h"
#include "xfs_error.h"
#include "xfs_rw.h"
#include "xfs_attr.h"
#include "xfs_buf_item.h"
#include "xfs_utils.h"
#include "xfs_qm.h"
#include "xfs_trace.h"

#ifdef DEBUG
# define qdprintk(s, args...)	cmn_err(CE_DEBUG, s, ## args)
#else
# define qdprintk(s, args...)	do { } while (0)
#endif

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 |= XFS_QMOPT_UQUOTA;
		flags |= (XFS_UQUOTA_CHKD | XFS_UQUOTA_ENFD);
		inactivate_flags |= XFS_UQUOTA_ACTIVE;
	}
	if (flags & XFS_GQUOTA_ACCT) {
		dqtype |= XFS_QMOPT_GQUOTA;
		flags |= (XFS_OQUOTA_CHKD | XFS_OQUOTA_ENFD);
		inactivate_flags |= XFS_GQUOTA_ACTIVE;
	} else if (flags & XFS_PQUOTA_ACCT) {
		dqtype |= XFS_QMOPT_PQUOTA;
		flags |= (XFS_OQUOTA_CHKD | XFS_OQUOTA_ENFD);
		inactivate_flags |= XFS_PQUOTA_ACTIVE;
	}

	/*
	 * Nothing to do?  Don't complain. This happens when we're just
	 * turning off quota enforcement.
	 */
	if ((mp->m_qflags & flags) == 0)
		goto out_unlock;

	/*
	 * Write the LI_QUOTAOFF log record, and do SB changes atomically,
	 * and synchronously. If we fail to write, we should abort the
	 * operation as it cannot be recovered safely if we crash.
	 */
	error = xfs_qm_log_quotaoff(mp, &qoffstart, flags);
	if (error)
		goto out_unlock;

	/*
	 * Next we clear the XFS_MOUNT_*DQ_ACTIVE bit(s) in the mount struct
	 * to take care of the race between dqget and quotaoff. We don't take
	 * any special locks to reset these bits. All processes need to check
	 * these bits *after* taking inode lock(s) to see if the particular
	 * quota type is in the process of being turned off. If *ACTIVE, it is
	 * guaranteed that all dquot structures and all quotainode ptrs will all
	 * stay valid as long as that inode is kept locked.
	 *
	 * There is no turning back after this.
	 */
	mp->m_qflags &= ~inactivate_flags;

	/*
	 * Give back all the dquot reference(s) held by inodes.
	 * Here we go thru every single incore inode in this file system, and
	 * do a dqrele on the i_udquot/i_gdquot that it may have.
	 * Essentially, as long as somebody has an inode locked, this guarantees
	 * that quotas will not be turned off. This is handy because in a
	 * transaction once we lock the inode(s) and check for quotaon, we can
	 * depend on the quota inodes (and other things) being valid as long as
	 * we keep the lock(s).
	 */
	xfs_qm_dqrele_all_inodes(mp, flags);

	/*
	 * Next we make the changes in the quota flag in the mount struct.
	 * This isn't protected by a particular lock directly, because we
	 * don't want to take a mrlock everytime we depend on quotas being on.
	 */
	mp->m_qflags &= ~(flags);

	/*
	 * Go through all the dquots of this file system and purge them,
	 * according to what was turned off. We may not be able to get rid
	 * of all dquots, because dquots can have temporary references that
	 * are not attached to inodes. eg. xfs_setattr, xfs_create.
	 * So, if we couldn't purge all the dquots from the filesystem,
	 * we can't get rid of the incore data structures.
	 */
	while ((nculprits = xfs_qm_dqpurge_all(mp, dqtype)))
		delay(10 * nculprits);

	/*
	 * Transactions that had started before ACTIVE state bit was cleared
	 * could have logged many dquots, so they'd have higher LSNs than
	 * the first QUOTAOFF log record does. If we happen to crash when
	 * the tail of the log has gone past the QUOTAOFF record, but
	 * before the last dquot modification, those dquots __will__
	 * recover, and that's not good.
	 *
	 * So, we have QUOTAOFF start and end logitems; the start
	 * logitem won't get overwritten until the end logitem appears...
	 */
	error = xfs_qm_log_quotaoff_end(mp, qoffstart, flags);
	if (error) {
		/* We're screwed now. Shutdown is the only option. */
		xfs_force_shutdown(mp, SHUTDOWN_CORRUPT_INCORE);
		goto out_unlock;
	}

	/*
	 * If quotas is completely disabled, close shop.
	 */
	if (((flags & XFS_MOUNT_QUOTA_ALL) == XFS_MOUNT_QUOTA_SET1) ||
	    ((flags & XFS_MOUNT_QUOTA_ALL) == XFS_MOUNT_QUOTA_SET2)) {
		mutex_unlock(&q->qi_quotaofflock);
		xfs_qm_destroy_quotainfo(mp);
		return (0);
	}

	/*
	 * Release our quotainode references if we don't need them anymore.
	 */
	if ((dqtype & XFS_QMOPT_UQUOTA) && q->qi_uquotaip) {
		IRELE(q->qi_uquotaip);
		q->qi_uquotaip = NULL;
	}
	if ((dqtype & (XFS_QMOPT_GQUOTA|XFS_QMOPT_PQUOTA)) && q->qi_gquotaip) {
		IRELE(q->qi_gquotaip);
		q->qi_gquotaip = NULL;
	}

out_unlock:
	mutex_unlock(&q->qi_quotaofflock);
	return error;
}

int
xfs_qm_scall_trunc_qfiles(
	xfs_mount_t	*mp,
	uint		flags)
{
	int		error = 0, error2 = 0;
	xfs_inode_t	*qip;

	if (!xfs_sb_version_hasquota(&mp->m_sb) || flags == 0) {
		qdprintk("qtrunc flags=%x m_qflags=%x\n", flags, mp->m_qflags);
		return XFS_ERROR(EINVAL);
	}

	if ((flags & XFS_DQ_USER) && mp->m_sb.sb_uquotino != NULLFSINO) {
		error = xfs_iget(mp, NULL, mp->m_sb.sb_uquotino, 0, 0, &qip);
		if (!error) {
			error = xfs_truncate_file(mp, qip);
			IRELE(qip);
		}
	}

	if ((flags & (XFS_DQ_GROUP|XFS_DQ_PROJ)) &&
	    mp->m_sb.sb_gquotino != NULLFSINO) {
		error2 = xfs_iget(mp, NULL, mp->m_sb.sb_gquotino, 0, 0, &qip);
		if (!error2) {
			error2 = xfs_truncate_file(mp, qip);
			IRELE(qip);
		}
	}

	return error ? error : error2;
}


/*
 * Switch on (a given) quota enforcement for a filesystem.  This takes
 * effect immediately.
 * (Switching on quota accounting must be done at mount time.)
 */
int
xfs_qm_scall_quotaon(
	xfs_mount_t	*mp,
	uint		flags)
{
	int		error;
	uint		qf;
	uint		accflags;
	__int64_t	sbflags;

	flags &= (XFS_ALL_QUOTA_ACCT | XFS_ALL_QUOTA_ENFD);
	/*
	 * Switching on quota accounting must be done at mount time.
	 */
	accflags = flags & XFS_ALL_QUOTA_ACCT;
	flags &= ~(XFS_ALL_QUOTA_ACCT);

	sbflags = 0;

	if (flags == 0) {
		qdprintk("quotaon: zero flags, m_qflags=%x\n", mp->m_qflags);
		return XFS_ERROR(EINVAL);
	}

	/* No fs can turn on quotas with a delayed effect */
	ASSERT((flags & XFS_ALL_QUOTA_ACCT) == 0);

	/*
	 * Can't enforce without accounting. We check the superblock
	 * qflags here instead of m_qflags because rootfs can have
	 * quota acct on ondisk without m_qflags' knowing.
	 */
	if (((flags & XFS_UQUOTA_ACCT) == 0 &&
	    (mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT) == 0 &&
	    (flags & XFS_UQUOTA_ENFD))
	    ||
	    ((flags & XFS_PQUOTA_ACCT) == 0 &&
	    (mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT) == 0 &&
	    (flags & XFS_GQUOTA_ACCT) == 0 &&
	    (mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT) == 0 &&
	    (flags & XFS_OQUOTA_ENFD))) {
		qdprintk("Can't enforce without acct, flags=%x sbflags=%x\n",
			flags, mp->m_sb.sb_qflags);
		return XFS_ERROR(EINVAL);
	}
	/*
	 * If everything's upto-date incore, then don't waste time.
	 */
	if ((mp->m_qflags & flags) == flags)
		return XFS_ERROR(EEXIST);

	/*
	 * Change sb_qflags on disk but not incore mp->qflags
	 * if this is the root filesystem.
	 */
	spin_lock(&mp->m_sb_lock);
	qf = mp->m_sb.sb_qflags;
	mp->m_sb.sb_qflags = qf | flags;
	spin_unlock(&mp->m_sb_lock);

	/*
	 * There's nothing to change if it's the same.
	 */
	if ((qf & flags) == flags && sbflags == 0)
		return XFS_ERROR(EEXIST);
	sbflags |= XFS_SB_QFLAGS;

	if ((error = xfs_qm_write_sb_changes(mp, sbflags)))
		return (error);
	/*
	 * If we aren't trying to switch on quota enforcement, we are done.
	 */
	if  (((mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT) !=
	     (mp->m_qflags & XFS_UQUOTA_ACCT)) ||
	     ((mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT) !=
	     (mp->m_qflags & XFS_PQUOTA_ACCT)) ||
	     ((mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT) !=
	     (mp->m_qflags & XFS_GQUOTA_ACCT)) ||
	    (flags & XFS_ALL_QUOTA_ENFD) == 0)
		return (0);

	if (! XFS_IS_QUOTA_RUNNING(mp))
		return XFS_ERROR(ESRCH);

	/*
	 * Switch on quota enforcement in core.
	 */
	mutex_lock(&mp->m_quotainfo->qi_quotaofflock);
	mp->m_qflags |= (flags & XFS_ALL_QUOTA_ENFD);
	mutex_unlock(&mp->m_quotainfo->qi_quotaofflock);

	return (0);
}


/*
 * Return quota status information, such as uquota-off, enforcements, etc.
 */
int
xfs_qm_scall_getqstat(
	struct xfs_mount	*mp,
	struct fs_quota_stat	*out)
{
	struct xfs_quotainfo	*q = mp->m_quotainfo;
	struct xfs_inode	*uip, *gip;
	boolean_t		tempuqip, tempgqip;

	uip = gip = NULL;
	tempuqip = tempgqip = B_FALSE;
	memset(out, 0, sizeof(fs_quota_stat_t));

	out->qs_version = FS_QSTAT_VERSION;
	if (!xfs_sb_version_hasquota(&mp->m_sb)) {
		out->qs_uquota.qfs_ino = NULLFSINO;
		out->qs_gquota.qfs_ino = NULLFSINO;
		return (0);
	}
	out->qs_flags = (__uint16_t) xfs_qm_export_flags(mp->m_qflags &
							(XFS_ALL_QUOTA_ACCT|
							 XFS_ALL_QUOTA_ENFD));
	out->qs_pad = 0;
	out->qs_uquota.qfs_ino = mp->m_sb.sb_uquotino;
	out->qs_gquota.qfs_ino = mp->m_sb.sb_gquotino;

	if (q) {
		uip = q->qi_uquotaip;
		gip = q->qi_gquotaip;
	}
	if (!uip && mp->m_sb.sb_uquotino != NULLFSINO) {
		if (xfs_iget(mp, NULL, mp->m_sb.sb_uquotino,
					0, 0, &uip) == 0)
			tempuqip = B_TRUE;
	}
	if (!gip && mp->m_sb.sb_gquotino != NULLFSINO) {
		if (xfs_iget(mp, NULL, mp->m_sb.sb_gquotino,
					0, 0, &gip) == 0)
			tempgqip = B_TRUE;
	}
	if (uip) {
		out->qs_uquota.qfs_nblks = uip->i_d.di_nblocks;
		out->qs_uquota.qfs_nextents = uip->i_d.di_nextents;
		if (tempuqip)
			IRELE(uip);
	}
	if (gip) {
		out->qs_gquota.qfs_nblks = gip->i_d.di_nblocks;
		out->qs_gquota.qfs_nextents = gip->i_d.di_nextents;
		if (tempgqip)
			IRELE(gip);
	}
	if (q) {
		out->qs_incoredqs = q->qi_dquots;
		out->qs_btimelimit = q->qi_btimelimit;
		out->qs_itimelimit = q->qi_itimelimit;
		out->qs_rtbtimelimit = q->qi_rtbtimelimit;
		out->qs_bwarnlimit = q->qi_bwarnlimit;
		out->qs_iwarnlimit = q->qi_iwarnlimit;
	}
	return 0;
}

#define XFS_DQ_MASK \
	(FS_DQ_LIMIT_MASK | FS_DQ_TIMER_MASK | FS_DQ_WARNS_MASK)

/*
 * Adjust quota limits, and start/stop timers accordingly.
 */
int
xfs_qm_scall_setqlim(
	xfs_mount_t		*mp,
	xfs_dqid_t		id,
	uint			type,
	fs_disk_quota_t		*newlim)
{
	struct xfs_quotainfo	*q = mp->m_quotainfo;
	xfs_disk_dquot_t	*ddq;
	xfs_dquot_t		*dqp;
	xfs_trans_t		*tp;
	int			error;
	xfs_qcnt_t		hard, soft;

	if (newlim->d_fieldmask & ~XFS_DQ_MASK)
		return EINVAL;
	if ((newlim->d_fieldmask & XFS_DQ_MASK) == 0)
		return 0;

	tp = xfs_trans_alloc(mp, XFS_TRANS_QM_SETQLIM);
	if ((error = xfs_trans_reserve(tp, 0, sizeof(xfs_disk_dquot_t) + 128,
				      0, 0, XFS_DEFAULT_LOG_COUNT))) {
		xfs_trans_cancel(tp, 0);
		return (error);
	}

	/*
	 * We don't want to race with a quotaoff so take the quotaoff lock.
	 * (We don't hold an inode lock, so there's nothing else to stop
	 * a quotaoff from happening). (XXXThis doesn't currently happen
	 * because we take the vfslock before calling xfs_qm_sysent).
	 */
	mutex_lock(&q->qi_quotaofflock);

	/*
	 * Get the dquot (locked), and join it to the transaction.
	 * Allocate the dquot if this doesn't exist.
	 */
	if ((error = xfs_qm_dqget(mp, NULL, id, type, XFS_QMOPT_DQALLOC, &dqp))) {
		xfs_trans_cancel(tp, XFS_TRANS_ABORT);
		ASSERT(error != ENOENT);
		goto out_unlock;
	}
	xfs_trans_dqjoin(tp, dqp);
	ddq = &dqp->q_core;

	/*
	 * Make sure that hardlimits are >= soft limits before changing.
	 */
	hard = (newlim->d_fieldmask & FS_DQ_BHARD) ?
		(xfs_qcnt_t) XFS_BB_TO_FSB(mp, newlim->d_blk_hardlimit) :
			be64_to_cpu(ddq->d_blk_hardlimit);
	soft = (newlim->d_fieldmask & FS_DQ_BSOFT) ?
		(xfs_qcnt_t) XFS_BB_TO_FSB(mp, newlim->d_blk_softlimit) :
			be64_to_cpu(ddq->d_blk_softlimit);
	if (hard == 0 || hard >= soft) {
		ddq->d_blk_hardlimit = cpu_to_be64(hard);
		ddq->d_blk_softlimit = cpu_to_be64(soft);
		if (id == 0) {
			q->qi_bhardlimit = hard;
			q->qi_bsoftlimit = soft;
		}
	} else {
		qdprintk("blkhard %Ld < blksoft %Ld\n", hard, soft);
	}
	hard = (newlim->d_fieldmask & FS_DQ_RTBHARD) ?
		(xfs_qcnt_t) XFS_BB_TO_FSB(mp, newlim->d_rtb_hardlimit) :
			be64_to_cpu(ddq->d_rtb_hardlimit);
	soft = (newlim->d_fieldmask & FS_DQ_RTBSOFT) ?
		(xfs_qcnt_t) XFS_BB_TO_FSB(mp, newlim->d_rtb_softlimit) :
			be64_to_cpu(ddq->d_rtb_softlimit);
	if (hard == 0 || hard >= soft) {
		ddq->d_rtb_hardlimit = cpu_to_be64(hard);
		ddq->d_rtb_softlimit = cpu_to_be64(soft);
		if (id == 0) {
			q->qi_rtbhardlimit = hard;
			q->qi_rtbsoftlimit = soft;
		}
	} else {
		qdprintk("rtbhard %Ld < rtbsoft %Ld\n", hard, soft);
	}

	hard = (newlim->d_fieldmask & FS_DQ_IHARD) ?
		(xfs_qcnt_t) newlim->d_ino_hardlimit :
			be64_to_cpu(ddq->d_ino_hardlimit);
	soft = (newlim->d_fieldmask & FS_DQ_ISOFT) ?
		(xfs_qcnt_t) newlim->d_ino_softlimit :
			be64_to_cpu(ddq->d_ino_softlimit);
	if (hard == 0 || hard >= soft) {
		ddq->d_ino_hardlimit = cpu_to_be64(hard);
		ddq->d_ino_softlimit = cpu_to_be64(soft);
		if (id == 0) {
			q->qi_ihardlimit = hard;
			q->qi_isoftlimit = soft;
		}
	} else {
		qdprintk("ihard %Ld < isoft %Ld\n", hard, soft);
	}

	/*
	 * Update warnings counter(s) if requested
	 */
	if (newlim->d_fieldmask & FS_DQ_BWARNS)
		ddq->d_bwarns = cpu_to_be16(newlim->d_bwarns);
	if (newlim->d_fieldmask & FS_DQ_IWARNS)
		ddq->d_iwarns = cpu_to_be16(newlim->d_iwarns);
	if (newlim->d_fieldmask & FS_DQ_RTBWARNS)
		ddq->d_rtbwarns = cpu_to_be16(newlim->d_rtbwarns);

	if (id == 0) {
		/*
		 * Timelimits for the super user set the relative time
		 * the other users can be over quota for this file system.
		 * If it is zero a default is used.  Ditto for the default
		 * soft and hard limit values (already done, above), and
		 * for warnings.
		 */
		if (newlim->d_fieldmask & FS_DQ_BTIMER) {
			q->qi_btimelimit = newlim->d_btimer;
			ddq->d_btimer = cpu_to_be32(newlim->d_btimer);
		}
		if (newlim->d_fieldmask & FS_DQ_ITIMER) {
			q->qi_itimelimit = newlim->d_itimer;
			ddq->d_itimer = cpu_to_be32(newlim->d_itimer);
		}
		if (newlim->d_fieldmask & FS_DQ_RTBTIMER) {
			q->qi_rtbtimelimit = newlim->d_rtbtimer;
			ddq->d_rtbtimer = cpu_to_be32(newlim->d_rtbtimer);
		}
		if (newlim->d_fieldmask & FS_DQ_BWARNS)
			q->qi_bwarnlimit = newlim->d_bwarns;
		if (newlim->d_fieldmask & FS_DQ_IWARNS)
			q->qi_iwarnlimit = newlim->d_iwarns;
		if (newlim->d_fieldmask & FS_DQ_RTBWARNS)
			q->qi_rtbwarnlimit = newlim->d_rtbwarns;
	} else {
		/*
		 * If the user is now over quota, start the timelimit.
		 * The user will not be 'warned'.
		 * Note that we keep the timers ticking, whether enforcement
		 * is on or off. We don't really want to bother with iterating
		 * over all ondisk dquots and turning the timers on/off.
		 */
		xfs_qm_adjust_dqtimers(mp, ddq);
	}
	dqp->dq_flags |= XFS_DQ_DIRTY;
	xfs_trans_log_dquot(tp, dqp);

	error = xfs_trans_commit(tp, 0);
	xfs_qm_dqprint(dqp);
	xfs_qm_dqrele(dqp);

 out_unlock:
	mutex_unlock(&q->qi_quotaofflock);
	return error;
}

int
xfs_qm_scall_getquota(
	xfs_mount_t	*mp,
	xfs_dqid_t	id,
	uint		type,
	fs_disk_quota_t *out)
{
	xfs_dquot_t	*dqp;
	int		error;

	/*
	 * Try to get the dquot. We don't want it allocated on disk, so
	 * we aren't passing the XFS_QMOPT_DOALLOC flag. If it doesn't
	 * exist, we'll get ENOENT back.
	 */
	if ((error = xfs_qm_dqget(mp, NULL, id, type, 0, &dqp))) {
		return (error);
	}

	/*
	 * If everything's NULL, this dquot doesn't quite exist as far as
	 * our utility programs are concerned.
	 */
	if (XFS_IS_DQUOT_UNINITIALIZED(dqp)) {
		xfs_qm_dqput(dqp);
		return XFS_ERROR(ENOENT);
	}
	/* xfs_qm_dqprint(dqp); */
	/*
	 * Convert the disk dquot to the exportable format
	 */
	xfs_qm_export_dquot(mp, &dqp->q_core, out);
	xfs_qm_dqput(dqp);
	return (error ? XFS_ERROR(EFAULT) : 0);
}


STATIC int
xfs_qm_log_quotaoff_end(
	xfs_mount_t		*mp,
	xfs_qoff_logitem_t	*startqoff,
	uint			flags)
{
	xfs_trans_t		*tp;
	int			error;
	xfs_qoff_logitem_t	*qoffi;

	tp = xfs_trans_alloc(mp, XFS_TRANS_QM_QUOTAOFF_END);

	if ((error = xfs_trans_reserve(tp, 0, sizeof(xfs_qoff_logitem_t) * 2,
				      0, 0, XFS_DEFAULT_LOG_COUNT))) {
		xfs_trans_cancel(tp, 0);
		return (error);
	}

	qoffi = xfs_trans_get_qoff_item(tp, startqoff,
					flags & XFS_ALL_QUOTA_ACCT);
	xfs_trans_log_quotaoff_item(tp, qoffi);

	/*
	 * We have to make sure that the transaction is secure on disk before we
	 * return and actually stop quota accounting. So, make it synchronous.
	 * We don't care about quotoff's performance.
	 */
	xfs_trans_set_sync(tp);
	error = xfs_trans_commit(tp, 0);
	return (error);
}


STATIC int
xfs_qm_log_quotaoff(
	xfs_mount_t	       *mp,
	xfs_qoff_logitem_t     **qoffstartp,
	uint		       flags)
{
	xfs_trans_t	       *tp;
	int			error;
	xfs_qoff_logitem_t     *qoffi=NULL;
	uint			oldsbqflag=0;

	tp = xfs_trans_alloc(mp, XFS_TRANS_QM_QUOTAOFF);
	if ((error = xfs_trans_reserve(tp, 0,
				      sizeof(xfs_qoff_logitem_t) * 2 +
				      mp->m_sb.sb_sectsize + 128,
				      0,
				      0,
				      XFS_DEFAULT_LOG_COUNT))) {
		goto error0;
	}

	qoffi = xfs_trans_get_qoff_item(tp, NULL, flags & XFS_ALL_QUOTA_ACCT);
	xfs_trans_log_quotaoff_item(tp, qoffi);

	spin_lock(&mp->m_sb_lock);
	oldsbqflag = mp->m_sb.sb_qflags;
	mp->m_sb.sb_qflags = (mp->m_qflags & ~(flags)) & XFS_MOUNT_QUOTA_ALL;
	spin_unlock(&mp->m_sb_lock);

	xfs_mod_sb(tp, XFS_SB_QFLAGS);

	/*
	 * We have to make sure that the transaction is secure on disk before we
	 * return and actually stop quota accounting. So, make it synchronous.
	 * We don't care about quotoff's performance.
	 */
	xfs_trans_set_sync(tp);
	error = xfs_trans_commit(tp, 0);

error0:
	if (error) {
		xfs_trans_cancel(tp, 0);
		/*
		 * No one else is modifying sb_qflags, so this is OK.
		 * We still hold the quotaofflock.
		 */
		spin_lock(&mp->m_sb_lock);
		mp->m_sb.sb_qflags = oldsbqflag;
		spin_unlock(&mp->m_sb_lock);
	}
	*qoffstartp = qoffi;
	return (error);
}


/*
 * Translate an internal style on-disk-dquot to the exportable format.
 * The main differences are that the counters/limits are all in Basic
 * Blocks (BBs) instead of the internal FSBs, and all on-disk data has
 * to be converted to the native endianness.
 */
STATIC void
xfs_qm_export_dquot(
	xfs_mount_t		*mp,
	xfs_disk_dquot_t	*src,
	struct fs_disk_quota	*dst)
{
	memset(dst, 0, sizeof(*dst));
	dst->d_version = FS_DQUOT_VERSION;  /* different from src->d_version */
	dst->d_flags = xfs_qm_export_qtype_flags(src->d_flags);
	dst->d_id = be32_to_cpu(src->d_id);
	dst->d_blk_hardlimit =
		XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_blk_hardlimit));
	dst->d_blk_softlimit =
		XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_blk_softlimit));
	dst->d_ino_hardlimit = be64_to_cpu(src->d_ino_hardlimit);
	dst->d_ino_softlimit = be64_to_cpu(src->d_ino_softlimit);
	dst->d_bcount = XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_bcount));
	dst->d_icount = be64_to_cpu(src->d_icount);
	dst->d_btimer = be32_to_cpu(src->d_btimer);
	dst->d_itimer = be32_to_cpu(src->d_itimer);
	dst->d_iwarns = be16_to_cpu(src->d_iwarns);
	dst->d_bwarns = be16_to_cpu(src->d_bwarns);
	dst->d_rtb_hardlimit =
		XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_rtb_hardlimit));
	dst->d_rtb_softlimit =
		XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_rtb_softlimit));
	dst->d_rtbcount = XFS_FSB_TO_BB(mp, be64_to_cpu(src->d_rtbcount));
	dst->d_rtbtimer = be32_to_cpu(src->d_rtbtimer);
	dst->d_rtbwarns = be16_to_cpu(src->d_rtbwarns);

	/*
	 * Internally, we don't reset all the timers when quota enforcement
	 * gets turned off. No need to confuse the user level code,
	 * so return zeroes in that case.
	 */
	if ((!XFS_IS_UQUOTA_ENFORCED(mp) && src->d_flags == XFS_DQ_USER) ||
	    (!XFS_IS_OQUOTA_ENFORCED(mp) &&
			(src->d_flags & (XFS_DQ_PROJ | XFS_DQ_GROUP)))) {
		dst->d_btimer = 0;
		dst->d_itimer = 0;
		dst->d_rtbtimer = 0;
	}

#ifdef DEBUG
	if (((XFS_IS_UQUOTA_ENFORCED(mp) && dst->d_flags == XFS_USER_QUOTA) ||
	     (XFS_IS_OQUOTA_ENFORCED(mp) &&
			(dst->d_flags & (XFS_PROJ_QUOTA | XFS_GROUP_QUOTA)))) &&
	    dst->d_id != 0) {
		if (((int) dst->d_bcount >= (int) dst->d_blk_softlimit) &&
		    (dst->d_blk_softlimit > 0)) {
			ASSERT(dst->d_btimer != 0);
		}
		if (((int) dst->d_icount >= (int) dst->d_ino_softlimit) &&
		    (dst->d_ino_softlimit > 0)) {
			ASSERT(dst->d_itimer != 0);
		}
	}
#endif
}

STATIC uint
xfs_qm_export_qtype_flags(
	uint flags)
{
	/*
	 * Can't be more than one, or none.
	 */
	ASSERT((flags & (XFS_PROJ_QUOTA | XFS_USER_QUOTA)) !=
		(XFS_PROJ_QUOTA | XFS_USER_QUOTA));
	ASSERT((flags & (XFS_PROJ_QUOTA | XFS_GROUP_QUOTA)) !=
		(XFS_PROJ_QUOTA | XFS_GROUP_QUOTA));
	ASSERT((flags & (XFS_USER_QUOTA | XFS_GROUP_QUOTA)) !=
		(XFS_USER_QUOTA | XFS_GROUP_QUOTA));
	ASSERT((flags & (XFS_PROJ_QUOTA|XFS_USER_QUOTA|XFS_GROUP_QUOTA)) != 0);

	return (flags & XFS_DQ_USER) ?
		XFS_USER_QUOTA : (flags & XFS_DQ_PROJ) ?
			XFS_PROJ_QUOTA : XFS_GROUP_QUOTA;
}

STATIC uint
xfs_qm_export_flags(
	uint flags)
{
	uint uflags;

	uflags = 0;
	if (flags & XFS_UQUOTA_ACCT)
		uflags |= XFS_QUOTA_UDQ_ACCT;
	if (flags & XFS_PQUOTA_ACCT)
		uflags |= XFS_QUOTA_PDQ_ACCT;
	if (flags & XFS_GQUOTA_ACCT)
		uflags |= XFS_QUOTA_GDQ_ACCT;
	if (flags & XFS_UQUOTA_ENFD)
		uflags |= XFS_QUOTA_UDQ_ENFD;
	if (flags & (XFS_OQUOTA_ENFD)) {
		uflags |= (flags & XFS_GQUOTA_ACCT) ?
			XFS_QUOTA_GDQ_ENFD : XFS_QUOTA_PDQ_ENFD;
	}
	return (uflags);
}


STATIC int
xfs_dqrele_inode(
	struct xfs_inode	*ip,
	struct xfs_perag	*pag,
	int			flags)
{
	int			error;

	/* skip quota inodes */
	if (ip == ip->i_mount->m_quotainfo->qi_uquotaip ||
	    ip == ip->i_mount->m_quotainfo->qi_gquotaip) {
		ASSERT(ip->i_udquot == NULL);
		ASSERT(ip->i_gdquot == NULL);
		read_unlock(&pag->pag_ici_lock);
		return 0;
	}

	error = xfs_sync_inode_valid(ip, pag);
	if (error)
		return error;

	xfs_ilock(ip, XFS_ILOCK_EXCL);
	if ((flags & XFS_UQUOTA_ACCT) && ip->i_udquot) {
		xfs_qm_dqrele(ip->i_udquot);
		ip->i_udquot = NULL;
	}
	if (flags & (XFS_PQUOTA_ACCT|XFS_GQUOTA_ACCT) && ip->i_gdquot) {
		xfs_qm_dqrele(ip->i_gdquot);
		ip->i_gdquot = NULL;
	}
	xfs_iput(ip, XFS_ILOCK_EXCL);

	return 0;
}


/*
 * Go thru all the inodes in the file system, releasing their dquots.
 *
 * Note that the mount structure gets modified to indicate that quotas are off
 * AFTER this, in the case of quotaoff.
 */
void
xfs_qm_dqrele_all_inodes(
	struct xfs_mount *mp,
	uint		 flags)
{
	ASSERT(mp->m_quotainfo);
	xfs_inode_ag_iterator(mp, xfs_dqrele_inode, flags,
				XFS_ICI_NO_TAG, 0, NULL);
}

/*------------------------------------------------------------------------*/
#ifdef DEBUG
/*
 * This contains all the test functions for XFS disk quotas.
 * Currently it does a quota accounting check. ie. it walks through
 * all inodes in the file system, calculating the dquot accounting fields,
 * and prints out any inconsistencies.
 */
xfs_dqhash_t *qmtest_udqtab;
xfs_dqhash_t *qmtest_gdqtab;
int	      qmtest_hashmask;
int	      qmtest_nfails;
struct mutex  qcheck_lock;

#define DQTEST_HASHVAL(mp, id) (((__psunsigned_t)(mp) + \
				 (__psunsigned_t)(id)) & \
				(qmtest_hashmask - 1))

#define DQTEST_HASH(mp, id, type)   ((type & XFS_DQ_USER) ? \
				     (qmtest_udqtab + \
				      DQTEST_HASHVAL(mp, id)) : \
				     (qmtest_gdqtab + \
				      DQTEST_HASHVAL(mp, id)))

#define DQTEST_LIST_PRINT(l, NXT, title) \
{ \
	  xfs_dqtest_t	*dqp; int i = 0;\
	  cmn_err(CE_DEBUG, "%s (#%d)", title, (int) (l)->qh_nelems); \
	  for (dqp = (xfs_dqtest_t *)(l)->qh_next; dqp != NULL; \
	       dqp = (xfs_dqtest_t *)dqp->NXT) { \
		cmn_err(CE_DEBUG, "  %d. \"%d (%s)\"  bcnt = %d, icnt = %d", \
			 ++i, dqp->d_id, DQFLAGTO_TYPESTR(dqp),	     \
			 dqp->d_bcount, dqp->d_icount); } \
}

typedef struct dqtest {
	uint		 dq_flags;	/* various flags (XFS_DQ_*) */
	struct list_head q_hashlist;
	xfs_dqhash_t	*q_hash;	/* the hashchain header */
	xfs_mount_t	*q_mount;	/* filesystem this relates to */
	xfs_dqid_t	d_id;		/* user id or group id */
	xfs_qcnt_t	d_bcount;	/* # disk blocks owned by the user */
	xfs_qcnt_t	d_icount;	/* # inodes owned by the user */
} xfs_dqtest_t;

STATIC void
xfs_qm_hashinsert(xfs_dqhash_t *h, xfs_dqtest_t *dqp)
{
	list_add(&dqp->q_hashlist, &h->qh_list);
	h->qh_version++;
	h->qh_nelems++;
}
STATIC void
xfs_qm_dqtest_print(
	xfs_dqtest_t	*d)
{
	cmn_err(CE_DEBUG, "-----------DQTEST DQUOT----------------");
	cmn_err(CE_DEBUG, "---- dquot ID = %d", d->d_id);
	cmn_err(CE_DEBUG, "---- fs       = 0x%p", d->q_mount);
	cmn_err(CE_DEBUG, "---- bcount   = %Lu (0x%x)",
		d->d_bcount, (int)d->d_bcount);
	cmn_err(CE_DEBUG, "---- icount   = %Lu (0x%x)",
		d->d_icount, (int)d->d_icount);
	cmn_err(CE_DEBUG, "---------------------------");
}

STATIC void
xfs_qm_dqtest_failed(
	xfs_dqtest_t	*d,
	xfs_dquot_t	*dqp,
	char		*reason,
	xfs_qcnt_t	a,
	xfs_qcnt_t	b,
	int		error)
{
	qmtest_nfails++;
	if (error)
		cmn_err(CE_DEBUG, "quotacheck failed id=%d, err=%d\nreason: %s",
		       d->d_id, error, reason);
	else
		cmn_err(CE_DEBUG, "quotacheck failed id=%d (%s) [%d != %d]",
		       d->d_id, reason, (int)a, (int)b);
	xfs_qm_dqtest_print(d);
	if (dqp)
		xfs_qm_dqprint(dqp);
}

STATIC int
xfs_dqtest_cmp2(
	xfs_dqtest_t	*d,
	xfs_dquot_t	*dqp)
{
	int err = 0;
	if (be64_to_cpu(dqp->q_core.d_icount) != d->d_icount) {
		xfs_qm_dqtest_failed(d, dqp, "icount mismatch",
			be64_to_cpu(dqp->q_core.d_icount),
			d->d_icount, 0);
		err++;
	}
	if (be64_to_cpu(dqp->q_core.d_bcount) != d->d_bcount) {
		xfs_qm_dqtest_failed(d, dqp, "bcount mismatch",
			be64_to_cpu(dqp->q_core.d_bcount),
			d->d_bcount, 0);
		err++;
	}
	if (dqp->q_core.d_blk_softlimit &&
	    be64_to_cpu(dqp->q_core.d_bcount) >=
	    be64_to_cpu(dqp->q_core.d_blk_softlimit)) {
		if (!dqp->q_core.d_btimer && dqp->q_core.d_id) {
			cmn_err(CE_DEBUG,
				"%d [%s] [0x%p] BLK TIMER NOT STARTED",
				d->d_id, DQFLAGTO_TYPESTR(d), d->q_mount);
			err++;
		}
	}
	if (dqp->q_core.d_ino_softlimit &&
	    be64_to_cpu(dqp->q_core.d_icount) >=
	    be64_to_cpu(dqp->q_core.d_ino_softlimit)) {
		if (!dqp->q_core.d_itimer && dqp->q_core.d_id) {
			cmn_err(CE_DEBUG,
				"%d [%s] [0x%p] INO TIMER NOT STARTED",
				d->d_id, DQFLAGTO_TYPESTR(d), d->q_mount);
			err++;
		}
	}
#ifdef QUOTADEBUG
	if (!err) {
		cmn_err(CE_DEBUG, "%d [%s] [0x%p] qchecked",
			d->d_id, DQFLAGTO_TYPESTR(d), d->q_mount);
	}
#endif
	return (err);
}

STATIC void
xfs_dqtest_cmp(
	xfs_dqtest_t	*d)
{
	xfs_dquot_t	*dqp;
	int		error;

	/* xfs_qm_dqtest_print(d); */
	if ((error = xfs_qm_dqget(d->q_mount, NULL, d->d_id, d->dq_flags, 0,
				 &dqp))) {
		xfs_qm_dqtest_failed(d, NULL, "dqget failed", 0, 0, error);
		return;
	}
	xfs_dqtest_cmp2(d, dqp);
	xfs_qm_dqput(dqp);
}

STATIC int
xfs_qm_internalqcheck_dqget(
	xfs_mount_t	*mp,
	xfs_dqid_t	id,
	uint		type,
	xfs_dqtest_t	**O_dq)
{
	xfs_dqtest_t	*d;
	xfs_dqhash_t	*h;

	h = DQTEST_HASH(mp, id, type);
	list_for_each_entry(d, &h->qh_list, q_hashlist) {
		if (d->d_id == id && mp == d->q_mount) {
			*O_dq = d;
			return (0);
		}
	}
	d = kmem_zalloc(sizeof(xfs_dqtest_t), KM_SLEEP);
	d->dq_flags = type;
	d->d_id = id;
	d->q_mount = mp;
	d->q_hash = h;
	INIT_LIST_HEAD(&d->q_hashlist);
	xfs_qm_hashinsert(h, d);
	*O_dq = d;
	return (0);
}

STATIC void
xfs_qm_internalqcheck_get_dquots(
	xfs_mount_t	*mp,
	xfs_dqid_t	uid,
	xfs_dqid_t	projid,
	xfs_dqid_t	gid,
	xfs_dqtest_t	**ud,
	xfs_dqtest_t	**gd)
{
	if (XFS_IS_UQUOTA_ON(mp))
		xfs_qm_internalqcheck_dqget(mp, uid, XFS_DQ_USER, ud);
	if (XFS_IS_GQUOTA_ON(mp))
		xfs_qm_internalqcheck_dqget(mp, gid, XFS_DQ_GROUP, gd);
	else if (XFS_IS_PQUOTA_ON(mp))
		xfs_qm_internalqcheck_dqget(mp, projid, XFS_DQ_PROJ, gd);
}


STATIC void
xfs_qm_internalqcheck_dqadjust(
	xfs_inode_t		*ip,
	xfs_dqtest_t		*d)
{
	d->d_icount++;
	d->d_bcount += (xfs_qcnt_t)ip->i_d.di_nblocks;
}

STATIC int
xfs_qm_internalqcheck_adjust(
	xfs_mount_t	*mp,		/* mount point for filesystem */
	xfs_ino_t	ino,		/* inode number to get data for */
	void		__user *buffer,	/* not used */
	int		ubsize,		/* not used */
	int		*ubused,	/* not used */
	int		*res)		/* bulkstat result code */
{
	xfs_inode_t		*ip;
	xfs_dqtest_t		*ud, *gd;
	uint			lock_flags;
	boolean_t		ipreleased;
	int			error;

	ASSERT(XFS_IS_QUOTA_RUNNING(mp));

	if (ino == mp->m_sb.sb_uquotino || ino == mp->m_sb.sb_gquotino) {
		*res = BULKSTAT_RV_NOTHING;
		qdprintk("internalqcheck: ino=%llu, uqino=%llu, gqino=%llu\n",
			(unsigned long long) ino,
			(unsigned long long) mp->m_sb.sb_uquotino,
			(unsigned long long) mp->m_sb.sb_gquotino);
		return XFS_ERROR(EINVAL);
	}
	ipreleased = B_FALSE;
 again:
	lock_flags = XFS_ILOCK_SHARED;
	if ((error = xfs_iget(mp, NULL, ino, 0, lock_flags, &ip))) {
		*res = BULKSTAT_RV_NOTHING;
		return (error);
	}

	/*
	 * This inode can have blocks after eof which can get released
	 * when we send it to inactive. Since we don't check the dquot
	 * until the after all our calculations are done, we must get rid
	 * of those now.
	 */
	if (! ipreleased) {
		xfs_iput(ip, lock_flags);
		ipreleased = B_TRUE;
		goto again;
	}
	xfs_qm_internalqcheck_get_dquots(mp,
					(xfs_dqid_t) ip->i_d.di_uid,
					(xfs_dqid_t) ip->i_d.di_projid,
					(xfs_dqid_t) ip->i_d.di_gid,
					&ud, &gd);
	if (XFS_IS_UQUOTA_ON(mp)) {
		ASSERT(ud);
		xfs_qm_internalqcheck_dqadjust(ip, ud);
	}
	if (XFS_IS_OQUOTA_ON(mp)) {
		ASSERT(gd);
		xfs_qm_internalqcheck_dqadjust(ip, gd);
	}
	xfs_iput(ip, lock_flags);
	*res = BULKSTAT_RV_DIDONE;
	return (0);
}


/* PRIVATE, debugging */
int
xfs_qm_internalqcheck(
	xfs_mount_t	*mp)
{
	xfs_ino_t	lastino;
	int		done, count;
	int		i;
	int		error;

	lastino = 0;
	qmtest_hashmask = 32;
	count = 5;
	done = 0;
	qmtest_nfails = 0;

	if (! XFS_IS_QUOTA_ON(mp))
		return XFS_ERROR(ESRCH);

	xfs_log_force(mp, XFS_LOG_SYNC);
	XFS_bflush(mp->m_ddev_targp);
	xfs_log_force(mp, XFS_LOG_SYNC);
	XFS_bflush(mp->m_ddev_targp);

	mutex_lock(&qcheck_lock);
	/* There should be absolutely no quota activity while this
	   is going on. */
	qmtest_udqtab = kmem_zalloc(qmtest_hashmask *
				    sizeof(xfs_dqhash_t), KM_SLEEP);
	qmtest_gdqtab = kmem_zalloc(qmtest_hashmask *
				    sizeof(xfs_dqhash_t), KM_SLEEP);
	do {
		/*
		 * Iterate thru all the inodes in the file system,
		 * adjusting the corresponding dquot counters
		 */
		error = xfs_bulkstat(mp, &lastino, &count,
				 xfs_qm_internalqcheck_adjust,
				 0, NULL, &done);
		if (error) {
			cmn_err(CE_DEBUG, "Bulkstat returned error 0x%x", error);
			break;
		}
	} while (!done);

	cmn_err(CE_DEBUG, "Checking results against system dquots");
	for (i = 0; i < qmtest_hashmask; i++) {
		xfs_dqtest_t	*d, *n;
		xfs_dqhash_t	*h;

		h = &qmtest_udqtab[i];
		list_for_each_entry_safe(d, n, &h->qh_list, q_hashlist) {
			xfs_dqtest_cmp(d);
			kmem_free(d);
		}
		h = &qmtest_gdqtab[i];
		list_for_each_entry_safe(d, n, &h->qh_list, q_hashlist) {
			xfs_dqtest_cmp(d);
			kmem_free(d);
		}
	}

	if (qmtest_nfails) {
		cmn_err(CE_DEBUG, "******** quotacheck failed  ********");
		cmn_err(CE_DEBUG, "failures = %d", qmtest_nfails);
	} else {
		cmn_err(CE_DEBUG, "******** quotacheck successful! ********");
	}
	kmem_free(qmtest_udqtab);
	kmem_free(qmtest_gdqtab);
	mutex_unlock(&qcheck_lock);
	return (qmtest_nfails);
}

#endif /* DEBUG */