Initial import

1 files changed, 1939 insertions, 0 deletions

diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
new file mode 100644
index 000000000..5538468c7
--- /dev/null
+++ b/fs/xfs/xfs_qm.c
@@ -0,0 +1,1939 @@
+/*
+ * Copyright (c) 2000-2005 Silicon Graphics, Inc.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_sb.h"
+#include "xfs_mount.h"
+#include "xfs_inode.h"
+#include "xfs_ialloc.h"
+#include "xfs_itable.h"
+#include "xfs_quota.h"
+#include "xfs_error.h"
+#include "xfs_bmap.h"
+#include "xfs_bmap_btree.h"
+#include "xfs_trans.h"
+#include "xfs_trans_space.h"
+#include "xfs_qm.h"
+#include "xfs_trace.h"
+#include "xfs_icache.h"
+#include "xfs_cksum.h"
+
+/*
+ * The global quota manager. There is only one of these for the entire
+ * system, _not_ one per file system. XQM keeps track of the overall
+ * quota functionality, including maintaining the freelist and hash
+ * tables of dquots.
+ */
+STATIC int	xfs_qm_init_quotainos(xfs_mount_t *);
+STATIC int	xfs_qm_init_quotainfo(xfs_mount_t *);
+
+
+STATIC void	xfs_qm_dqfree_one(struct xfs_dquot *dqp);
+/*
+ * We use the batch lookup interface to iterate over the dquots as it
+ * currently is the only interface into the radix tree code that allows
+ * fuzzy lookups instead of exact matches.  Holding the lock over multiple
+ * operations is fine as all callers are used either during mount/umount
+ * or quotaoff.
+ */
+#define XFS_DQ_LOOKUP_BATCH	32
+
+STATIC int
+xfs_qm_dquot_walk(
+	struct xfs_mount	*mp,
+	int			type,
+	int			(*execute)(struct xfs_dquot *dqp, void *data),
+	void			*data)
+{
+	struct xfs_quotainfo	*qi = mp->m_quotainfo;
+	struct radix_tree_root	*tree = xfs_dquot_tree(qi, type);
+	uint32_t		next_index;
+	int			last_error = 0;
+	int			skipped;
+	int			nr_found;
+
+restart:
+	skipped = 0;
+	next_index = 0;
+	nr_found = 0;
+
+	while (1) {
+		struct xfs_dquot *batch[XFS_DQ_LOOKUP_BATCH];
+		int		error = 0;
+		int		i;
+
+		mutex_lock(&qi->qi_tree_lock);
+		nr_found = radix_tree_gang_lookup(tree, (void **)batch,
+					next_index, XFS_DQ_LOOKUP_BATCH);
+		if (!nr_found) {
+			mutex_unlock(&qi->qi_tree_lock);
+			break;
+		}
+
+		for (i = 0; i < nr_found; i++) {
+			struct xfs_dquot *dqp = batch[i];
+
+			next_index = be32_to_cpu(dqp->q_core.d_id) + 1;
+
+			error = execute(batch[i], data);
+			if (error == -EAGAIN) {
+				skipped++;
+				continue;
+			}
+			if (error && last_error != -EFSCORRUPTED)
+				last_error = error;
+		}
+
+		mutex_unlock(&qi->qi_tree_lock);
+
+		/* bail out if the filesystem is corrupted.  */
+		if (last_error == -EFSCORRUPTED) {
+			skipped = 0;
+			break;
+		}
+	}
+
+	if (skipped) {
+		delay(1);
+		goto restart;
+	}
+
+	return last_error;
+}
+
+
+/*
+ * Purge a dquot from all tracking data structures and free it.
+ */
+STATIC int
+xfs_qm_dqpurge(
+	struct xfs_dquot	*dqp,
+	void			*data)
+{
+	struct xfs_mount	*mp = dqp->q_mount;
+	struct xfs_quotainfo	*qi = mp->m_quotainfo;
+
+	xfs_dqlock(dqp);
+	if ((dqp->dq_flags & XFS_DQ_FREEING) || dqp->q_nrefs != 0) {
+		xfs_dqunlock(dqp);
+		return -EAGAIN;
+	}
+
+	dqp->dq_flags |= XFS_DQ_FREEING;
+
+	xfs_dqflock(dqp);
+
+	/*
+	 * If we are turning this type of quotas off, we don't care
+	 * about the dirty metadata sitting in this dquot. OTOH, if
+	 * we're unmounting, we do care, so we flush it and wait.
+	 */
+	if (XFS_DQ_IS_DIRTY(dqp)) {
+		struct xfs_buf	*bp = NULL;
+		int		error;
+
+		/*
+		 * We don't care about getting disk errors here. We need
+		 * to purge this dquot anyway, so we go ahead regardless.
+		 */
+		error = xfs_qm_dqflush(dqp, &bp);
+		if (error) {
+			xfs_warn(mp, "%s: dquot %p flush failed",
+				__func__, dqp);
+		} else {
+			error = xfs_bwrite(bp);
+			xfs_buf_relse(bp);
+		}
+		xfs_dqflock(dqp);
+	}
+
+	ASSERT(atomic_read(&dqp->q_pincount) == 0);
+	ASSERT(XFS_FORCED_SHUTDOWN(mp) ||
+	       !(dqp->q_logitem.qli_item.li_flags & XFS_LI_IN_AIL));
+
+	xfs_dqfunlock(dqp);
+	xfs_dqunlock(dqp);
+
+	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags),
+			  be32_to_cpu(dqp->q_core.d_id));
+	qi->qi_dquots--;
+
+	/*
+	 * We move dquots to the freelist as soon as their reference count
+	 * hits zero, so it really should be on the freelist here.
+	 */
+	ASSERT(!list_empty(&dqp->q_lru));
+	list_lru_del(&qi->qi_lru, &dqp->q_lru);
+	XFS_STATS_DEC(xs_qm_dquot_unused);
+
+	xfs_qm_dqdestroy(dqp);
+	return 0;
+}
+
+/*
+ * Purge the dquot cache.
+ */
+void
+xfs_qm_dqpurge_all(
+	struct xfs_mount	*mp,
+	uint			flags)
+{
+	if (flags & XFS_QMOPT_UQUOTA)
+		xfs_qm_dquot_walk(mp, XFS_DQ_USER, xfs_qm_dqpurge, NULL);
+	if (flags & XFS_QMOPT_GQUOTA)
+		xfs_qm_dquot_walk(mp, XFS_DQ_GROUP, xfs_qm_dqpurge, NULL);
+	if (flags & XFS_QMOPT_PQUOTA)
+		xfs_qm_dquot_walk(mp, XFS_DQ_PROJ, xfs_qm_dqpurge, NULL);
+}
+
+/*
+ * Just destroy the quotainfo structure.
+ */
+void
+xfs_qm_unmount(
+	struct xfs_mount	*mp)
+{
+	if (mp->m_quotainfo) {
+		xfs_qm_dqpurge_all(mp, XFS_QMOPT_QUOTALL);
+		xfs_qm_destroy_quotainfo(mp);
+	}
+}
+
+/*
+ * Called from the vfsops layer.
+ */
+void
+xfs_qm_unmount_quotas(
+	xfs_mount_t	*mp)
+{
+	/*
+	 * Release the dquots that root inode, et al might be holding,
+	 * before we flush quotas and blow away the quotainfo structure.
+	 */
+	ASSERT(mp->m_rootip);
+	xfs_qm_dqdetach(mp->m_rootip);
+	if (mp->m_rbmip)
+		xfs_qm_dqdetach(mp->m_rbmip);
+	if (mp->m_rsumip)
+		xfs_qm_dqdetach(mp->m_rsumip);
+
+	/*
+	 * Release the quota inodes.
+	 */
+	if (mp->m_quotainfo) {
+		if (mp->m_quotainfo->qi_uquotaip) {
+			IRELE(mp->m_quotainfo->qi_uquotaip);
+			mp->m_quotainfo->qi_uquotaip = NULL;
+		}
+		if (mp->m_quotainfo->qi_gquotaip) {
+			IRELE(mp->m_quotainfo->qi_gquotaip);
+			mp->m_quotainfo->qi_gquotaip = NULL;
+		}
+		if (mp->m_quotainfo->qi_pquotaip) {
+			IRELE(mp->m_quotainfo->qi_pquotaip);
+			mp->m_quotainfo->qi_pquotaip = NULL;
+		}
+	}
+}
+
+STATIC int
+xfs_qm_dqattach_one(
+	xfs_inode_t	*ip,
+	xfs_dqid_t	id,
+	uint		type,
+	uint		doalloc,
+	xfs_dquot_t	**IO_idqpp)
+{
+	xfs_dquot_t	*dqp;
+	int		error;
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+	error = 0;
+
+	/*
+	 * See if we already have it in the inode itself. IO_idqpp is &i_udquot
+	 * or &i_gdquot. This made the code look weird, but made the logic a lot
+	 * simpler.
+	 */
+	dqp = *IO_idqpp;
+	if (dqp) {
+		trace_xfs_dqattach_found(dqp);
+		return 0;
+	}
+
+	/*
+	 * Find the dquot from somewhere. This bumps the reference count of
+	 * dquot and returns it locked.  This can return ENOENT if dquot didn't
+	 * exist on disk and we didn't ask it to allocate; ESRCH if quotas got
+	 * turned off suddenly.
+	 */
+	error = xfs_qm_dqget(ip->i_mount, ip, id, type,
+			     doalloc | XFS_QMOPT_DOWARN, &dqp);
+	if (error)
+		return error;
+
+	trace_xfs_dqattach_get(dqp);
+
+	/*
+	 * dqget may have dropped and re-acquired the ilock, but it guarantees
+	 * that the dquot returned is the one that should go in the inode.
+	 */
+	*IO_idqpp = dqp;
+	xfs_dqunlock(dqp);
+	return 0;
+}
+
+static bool
+xfs_qm_need_dqattach(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+
+	if (!XFS_IS_QUOTA_RUNNING(mp))
+		return false;
+	if (!XFS_IS_QUOTA_ON(mp))
+		return false;
+	if (!XFS_NOT_DQATTACHED(mp, ip))
+		return false;
+	if (xfs_is_quota_inode(&mp->m_sb, ip->i_ino))
+		return false;
+	return true;
+}
+
+/*
+ * Given a locked inode, attach dquot(s) to it, taking U/G/P-QUOTAON
+ * into account.
+ * If XFS_QMOPT_DQALLOC, the dquot(s) will be allocated if needed.
+ * Inode may get unlocked and relocked in here, and the caller must deal with
+ * the consequences.
+ */
+int
+xfs_qm_dqattach_locked(
+	xfs_inode_t	*ip,
+	uint		flags)
+{
+	xfs_mount_t	*mp = ip->i_mount;
+	int		error = 0;
+
+	if (!xfs_qm_need_dqattach(ip))
+		return 0;
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+
+	if (XFS_IS_UQUOTA_ON(mp) && !ip->i_udquot) {
+		error = xfs_qm_dqattach_one(ip, ip->i_d.di_uid, XFS_DQ_USER,
+						flags & XFS_QMOPT_DQALLOC,
+						&ip->i_udquot);
+		if (error)
+			goto done;
+		ASSERT(ip->i_udquot);
+	}
+
+	if (XFS_IS_GQUOTA_ON(mp) && !ip->i_gdquot) {
+		error = xfs_qm_dqattach_one(ip, ip->i_d.di_gid, XFS_DQ_GROUP,
+						flags & XFS_QMOPT_DQALLOC,
+						&ip->i_gdquot);
+		if (error)
+			goto done;
+		ASSERT(ip->i_gdquot);
+	}
+
+	if (XFS_IS_PQUOTA_ON(mp) && !ip->i_pdquot) {
+		error = xfs_qm_dqattach_one(ip, xfs_get_projid(ip), XFS_DQ_PROJ,
+						flags & XFS_QMOPT_DQALLOC,
+						&ip->i_pdquot);
+		if (error)
+			goto done;
+		ASSERT(ip->i_pdquot);
+	}
+
+done:
+	/*
+	 * Don't worry about the dquots that we may have attached before any
+	 * error - they'll get detached later if it has not already been done.
+	 */
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+	return error;
+}
+
+int
+xfs_qm_dqattach(
+	struct xfs_inode	*ip,
+	uint			flags)
+{
+	int			error;
+
+	if (!xfs_qm_need_dqattach(ip))
+		return 0;
+
+	xfs_ilock(ip, XFS_ILOCK_EXCL);
+	error = xfs_qm_dqattach_locked(ip, flags);
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+
+	return error;
+}
+
+/*
+ * Release dquots (and their references) if any.
+ * The inode should be locked EXCL except when this's called by
+ * xfs_ireclaim.
+ */
+void
+xfs_qm_dqdetach(
+	xfs_inode_t	*ip)
+{
+	if (!(ip->i_udquot || ip->i_gdquot || ip->i_pdquot))
+		return;
+
+	trace_xfs_dquot_dqdetach(ip);
+
+	ASSERT(!xfs_is_quota_inode(&ip->i_mount->m_sb, ip->i_ino));
+	if (ip->i_udquot) {
+		xfs_qm_dqrele(ip->i_udquot);
+		ip->i_udquot = NULL;
+	}
+	if (ip->i_gdquot) {
+		xfs_qm_dqrele(ip->i_gdquot);
+		ip->i_gdquot = NULL;
+	}
+	if (ip->i_pdquot) {
+		xfs_qm_dqrele(ip->i_pdquot);
+		ip->i_pdquot = NULL;
+	}
+}
+
+struct xfs_qm_isolate {
+	struct list_head	buffers;
+	struct list_head	dispose;
+};
+
+static enum lru_status
+xfs_qm_dquot_isolate(
+	struct list_head	*item,
+	struct list_lru_one	*lru,
+	spinlock_t		*lru_lock,
+	void			*arg)
+		__releases(lru_lock) __acquires(lru_lock)
+{
+	struct xfs_dquot	*dqp = container_of(item,
+						struct xfs_dquot, q_lru);
+	struct xfs_qm_isolate	*isol = arg;
+
+	if (!xfs_dqlock_nowait(dqp))
+		goto out_miss_busy;
+
+	/*
+	 * This dquot has acquired a reference in the meantime remove it from
+	 * the freelist and try again.
+	 */
+	if (dqp->q_nrefs) {
+		xfs_dqunlock(dqp);
+		XFS_STATS_INC(xs_qm_dqwants);
+
+		trace_xfs_dqreclaim_want(dqp);
+		list_lru_isolate(lru, &dqp->q_lru);
+		XFS_STATS_DEC(xs_qm_dquot_unused);
+		return LRU_REMOVED;
+	}
+
+	/*
+	 * If the dquot is dirty, flush it. If it's already being flushed, just
+	 * skip it so there is time for the IO to complete before we try to
+	 * reclaim it again on the next LRU pass.
+	 */
+	if (!xfs_dqflock_nowait(dqp)) {
+		xfs_dqunlock(dqp);
+		goto out_miss_busy;
+	}
+
+	if (XFS_DQ_IS_DIRTY(dqp)) {
+		struct xfs_buf	*bp = NULL;
+		int		error;
+
+		trace_xfs_dqreclaim_dirty(dqp);
+
+		/* we have to drop the LRU lock to flush the dquot */
+		spin_unlock(lru_lock);
+
+		error = xfs_qm_dqflush(dqp, &bp);
+		if (error) {
+			xfs_warn(dqp->q_mount, "%s: dquot %p flush failed",
+				 __func__, dqp);
+			goto out_unlock_dirty;
+		}
+
+		xfs_buf_delwri_queue(bp, &isol->buffers);
+		xfs_buf_relse(bp);
+		goto out_unlock_dirty;
+	}
+	xfs_dqfunlock(dqp);
+
+	/*
+	 * Prevent lookups now that we are past the point of no return.
+	 */
+	dqp->dq_flags |= XFS_DQ_FREEING;
+	xfs_dqunlock(dqp);
+
+	ASSERT(dqp->q_nrefs == 0);
+	list_lru_isolate_move(lru, &dqp->q_lru, &isol->dispose);
+	XFS_STATS_DEC(xs_qm_dquot_unused);
+	trace_xfs_dqreclaim_done(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaims);
+	return LRU_REMOVED;
+
+out_miss_busy:
+	trace_xfs_dqreclaim_busy(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaim_misses);
+	return LRU_SKIP;
+
+out_unlock_dirty:
+	trace_xfs_dqreclaim_busy(dqp);
+	XFS_STATS_INC(xs_qm_dqreclaim_misses);
+	xfs_dqunlock(dqp);
+	spin_lock(lru_lock);
+	return LRU_RETRY;
+}
+
+static unsigned long
+xfs_qm_shrink_scan(
+	struct shrinker		*shrink,
+	struct shrink_control	*sc)
+{
+	struct xfs_quotainfo	*qi = container_of(shrink,
+					struct xfs_quotainfo, qi_shrinker);
+	struct xfs_qm_isolate	isol;
+	unsigned long		freed;
+	int			error;
+
+	if ((sc->gfp_mask & (__GFP_FS|__GFP_WAIT)) != (__GFP_FS|__GFP_WAIT))
+		return 0;
+
+	INIT_LIST_HEAD(&isol.buffers);
+	INIT_LIST_HEAD(&isol.dispose);
+
+	freed = list_lru_shrink_walk(&qi->qi_lru, sc,
+				     xfs_qm_dquot_isolate, &isol);
+
+	error = xfs_buf_delwri_submit(&isol.buffers);
+	if (error)
+		xfs_warn(NULL, "%s: dquot reclaim failed", __func__);
+
+	while (!list_empty(&isol.dispose)) {
+		struct xfs_dquot	*dqp;
+
+		dqp = list_first_entry(&isol.dispose, struct xfs_dquot, q_lru);
+		list_del_init(&dqp->q_lru);
+		xfs_qm_dqfree_one(dqp);
+	}
+
+	return freed;
+}
+
+static unsigned long
+xfs_qm_shrink_count(
+	struct shrinker		*shrink,
+	struct shrink_control	*sc)
+{
+	struct xfs_quotainfo	*qi = container_of(shrink,
+					struct xfs_quotainfo, qi_shrinker);
+
+	return list_lru_shrink_count(&qi->qi_lru, sc);
+}
+
+/*
+ * This initializes all the quota information that's kept in the
+ * mount structure
+ */
+STATIC int
+xfs_qm_init_quotainfo(
+	xfs_mount_t	*mp)
+{
+	xfs_quotainfo_t *qinf;
+	int		error;
+	xfs_dquot_t	*dqp;
+
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	qinf = mp->m_quotainfo = kmem_zalloc(sizeof(xfs_quotainfo_t), KM_SLEEP);
+
+	error = list_lru_init(&qinf->qi_lru);
+	if (error)
+		goto out_free_qinf;
+
+	/*
+	 * See if quotainodes are setup, and if not, allocate them,
+	 * and change the superblock accordingly.
+	 */
+	error = xfs_qm_init_quotainos(mp);
+	if (error)
+		goto out_free_lru;
+
+	INIT_RADIX_TREE(&qinf->qi_uquota_tree, GFP_NOFS);
+	INIT_RADIX_TREE(&qinf->qi_gquota_tree, GFP_NOFS);
+	INIT_RADIX_TREE(&qinf->qi_pquota_tree, GFP_NOFS);
+	mutex_init(&qinf->qi_tree_lock);
+
+	/* mutex used to serialize quotaoffs */
+	mutex_init(&qinf->qi_quotaofflock);
+
+	/* Precalc some constants */
+	qinf->qi_dqchunklen = XFS_FSB_TO_BB(mp, XFS_DQUOT_CLUSTER_SIZE_FSB);
+	qinf->qi_dqperchunk = xfs_calc_dquots_per_chunk(qinf->qi_dqchunklen);
+
+	mp->m_qflags |= (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_CHKD);
+
+	/*
+	 * We try to get the limits from the superuser's limits fields.
+	 * This is quite hacky, but it is standard quota practice.
+	 *
+	 * We look at the USR dquot with id == 0 first, but if user quotas
+	 * are not enabled we goto the GRP dquot with id == 0.
+	 * We don't really care to keep separate default limits for user
+	 * and group quotas, at least not at this point.
+	 *
+	 * Since we may not have done a quotacheck by this point, just read
+	 * the dquot without attaching it to any hashtables or lists.
+	 */
+	error = xfs_qm_dqread(mp, 0,
+			XFS_IS_UQUOTA_RUNNING(mp) ? XFS_DQ_USER :
+			 (XFS_IS_GQUOTA_RUNNING(mp) ? XFS_DQ_GROUP :
+			  XFS_DQ_PROJ),
+			XFS_QMOPT_DOWARN, &dqp);
+	if (!error) {
+		xfs_disk_dquot_t	*ddqp = &dqp->q_core;
+
+		/*
+		 * The warnings and timers set the grace period given to
+		 * a user or group before he or she can not perform any
+		 * more writing. If it is zero, a default is used.
+		 */
+		qinf->qi_btimelimit = ddqp->d_btimer ?
+			be32_to_cpu(ddqp->d_btimer) : XFS_QM_BTIMELIMIT;
+		qinf->qi_itimelimit = ddqp->d_itimer ?
+			be32_to_cpu(ddqp->d_itimer) : XFS_QM_ITIMELIMIT;
+		qinf->qi_rtbtimelimit = ddqp->d_rtbtimer ?
+			be32_to_cpu(ddqp->d_rtbtimer) : XFS_QM_RTBTIMELIMIT;
+		qinf->qi_bwarnlimit = ddqp->d_bwarns ?
+			be16_to_cpu(ddqp->d_bwarns) : XFS_QM_BWARNLIMIT;
+		qinf->qi_iwarnlimit = ddqp->d_iwarns ?
+			be16_to_cpu(ddqp->d_iwarns) : XFS_QM_IWARNLIMIT;
+		qinf->qi_rtbwarnlimit = ddqp->d_rtbwarns ?
+			be16_to_cpu(ddqp->d_rtbwarns) : XFS_QM_RTBWARNLIMIT;
+		qinf->qi_bhardlimit = be64_to_cpu(ddqp->d_blk_hardlimit);
+		qinf->qi_bsoftlimit = be64_to_cpu(ddqp->d_blk_softlimit);
+		qinf->qi_ihardlimit = be64_to_cpu(ddqp->d_ino_hardlimit);
+		qinf->qi_isoftlimit = be64_to_cpu(ddqp->d_ino_softlimit);
+		qinf->qi_rtbhardlimit = be64_to_cpu(ddqp->d_rtb_hardlimit);
+		qinf->qi_rtbsoftlimit = be64_to_cpu(ddqp->d_rtb_softlimit);
+
+		xfs_qm_dqdestroy(dqp);
+	} else {
+		qinf->qi_btimelimit = XFS_QM_BTIMELIMIT;
+		qinf->qi_itimelimit = XFS_QM_ITIMELIMIT;
+		qinf->qi_rtbtimelimit = XFS_QM_RTBTIMELIMIT;
+		qinf->qi_bwarnlimit = XFS_QM_BWARNLIMIT;
+		qinf->qi_iwarnlimit = XFS_QM_IWARNLIMIT;
+		qinf->qi_rtbwarnlimit = XFS_QM_RTBWARNLIMIT;
+	}
+
+	qinf->qi_shrinker.count_objects = xfs_qm_shrink_count;
+	qinf->qi_shrinker.scan_objects = xfs_qm_shrink_scan;
+	qinf->qi_shrinker.seeks = DEFAULT_SEEKS;
+	qinf->qi_shrinker.flags = SHRINKER_NUMA_AWARE;
+	register_shrinker(&qinf->qi_shrinker);
+	return 0;
+
+out_free_lru:
+	list_lru_destroy(&qinf->qi_lru);
+out_free_qinf:
+	kmem_free(qinf);
+	mp->m_quotainfo = NULL;
+	return error;
+}
+
+
+/*
+ * Gets called when unmounting a filesystem or when all quotas get
+ * turned off.
+ * This purges the quota inodes, destroys locks and frees itself.
+ */
+void
+xfs_qm_destroy_quotainfo(
+	xfs_mount_t	*mp)
+{
+	xfs_quotainfo_t *qi;
+
+	qi = mp->m_quotainfo;
+	ASSERT(qi != NULL);
+
+	unregister_shrinker(&qi->qi_shrinker);
+	list_lru_destroy(&qi->qi_lru);
+
+	if (qi->qi_uquotaip) {
+		IRELE(qi->qi_uquotaip);
+		qi->qi_uquotaip = NULL; /* paranoia */
+	}
+	if (qi->qi_gquotaip) {
+		IRELE(qi->qi_gquotaip);
+		qi->qi_gquotaip = NULL;
+	}
+	if (qi->qi_pquotaip) {
+		IRELE(qi->qi_pquotaip);
+		qi->qi_pquotaip = NULL;
+	}
+	mutex_destroy(&qi->qi_quotaofflock);
+	kmem_free(qi);
+	mp->m_quotainfo = NULL;
+}
+
+/*
+ * Create an inode and return with a reference already taken, but unlocked
+ * This is how we create quota inodes
+ */
+STATIC int
+xfs_qm_qino_alloc(
+	xfs_mount_t	*mp,
+	xfs_inode_t	**ip,
+	uint		flags)
+{
+	xfs_trans_t	*tp;
+	int		error;
+	int		committed;
+	bool		need_alloc = true;
+
+	*ip = NULL;
+	/*
+	 * With superblock that doesn't have separate pquotino, we
+	 * share an inode between gquota and pquota. If the on-disk
+	 * superblock has GQUOTA and the filesystem is now mounted
+	 * with PQUOTA, just use sb_gquotino for sb_pquotino and
+	 * vice-versa.
+	 */
+	if (!xfs_sb_version_has_pquotino(&mp->m_sb) &&
+			(flags & (XFS_QMOPT_PQUOTA|XFS_QMOPT_GQUOTA))) {
+		xfs_ino_t ino = NULLFSINO;
+
+		if ((flags & XFS_QMOPT_PQUOTA) &&
+			     (mp->m_sb.sb_gquotino != NULLFSINO)) {
+			ino = mp->m_sb.sb_gquotino;
+			ASSERT(mp->m_sb.sb_pquotino == NULLFSINO);
+		} else if ((flags & XFS_QMOPT_GQUOTA) &&
+			     (mp->m_sb.sb_pquotino != NULLFSINO)) {
+			ino = mp->m_sb.sb_pquotino;
+			ASSERT(mp->m_sb.sb_gquotino == NULLFSINO);
+		}
+		if (ino != NULLFSINO) {
+			error = xfs_iget(mp, NULL, ino, 0, 0, ip);
+			if (error)
+				return error;
+			mp->m_sb.sb_gquotino = NULLFSINO;
+			mp->m_sb.sb_pquotino = NULLFSINO;
+			need_alloc = false;
+		}
+	}
+
+	tp = xfs_trans_alloc(mp, XFS_TRANS_QM_QINOCREATE);
+	error = xfs_trans_reserve(tp, &M_RES(mp)->tr_create,
+				  XFS_QM_QINOCREATE_SPACE_RES(mp), 0);
+	if (error) {
+		xfs_trans_cancel(tp, 0);
+		return error;
+	}
+
+	if (need_alloc) {
+		error = xfs_dir_ialloc(&tp, NULL, S_IFREG, 1, 0, 0, 1, ip,
+								&committed);
+		if (error) {
+			xfs_trans_cancel(tp, XFS_TRANS_RELEASE_LOG_RES |
+					 XFS_TRANS_ABORT);
+			return error;
+		}
+	}
+
+	/*
+	 * Make the changes in the superblock, and log those too.
+	 * sbfields arg may contain fields other than *QUOTINO;
+	 * VERSIONNUM for example.
+	 */
+	spin_lock(&mp->m_sb_lock);
+	if (flags & XFS_QMOPT_SBVERSION) {
+		ASSERT(!xfs_sb_version_hasquota(&mp->m_sb));
+
+		xfs_sb_version_addquota(&mp->m_sb);
+		mp->m_sb.sb_uquotino = NULLFSINO;
+		mp->m_sb.sb_gquotino = NULLFSINO;
+		mp->m_sb.sb_pquotino = NULLFSINO;
+
+		/* qflags will get updated fully _after_ quotacheck */
+		mp->m_sb.sb_qflags = mp->m_qflags & XFS_ALL_QUOTA_ACCT;
+	}
+	if (flags & XFS_QMOPT_UQUOTA)
+		mp->m_sb.sb_uquotino = (*ip)->i_ino;
+	else if (flags & XFS_QMOPT_GQUOTA)
+		mp->m_sb.sb_gquotino = (*ip)->i_ino;
+	else
+		mp->m_sb.sb_pquotino = (*ip)->i_ino;
+	spin_unlock(&mp->m_sb_lock);
+	xfs_log_sb(tp);
+
+	error = xfs_trans_commit(tp, XFS_TRANS_RELEASE_LOG_RES);
+	if (error) {
+		ASSERT(XFS_FORCED_SHUTDOWN(mp));
+		xfs_alert(mp, "%s failed (error %d)!", __func__, error);
+	}
+	if (need_alloc)
+		xfs_finish_inode_setup(*ip);
+	return error;
+}
+
+
+STATIC void
+xfs_qm_reset_dqcounts(
+	xfs_mount_t	*mp,
+	xfs_buf_t	*bp,
+	xfs_dqid_t	id,
+	uint		type)
+{
+	struct xfs_dqblk	*dqb;
+	int			j;
+
+	trace_xfs_reset_dqcounts(bp, _RET_IP_);
+
+	/*
+	 * Reset all counters and timers. They'll be
+	 * started afresh by xfs_qm_quotacheck.
+	 */
+#ifdef DEBUG
+	j = XFS_FSB_TO_B(mp, XFS_DQUOT_CLUSTER_SIZE_FSB);
+	do_div(j, sizeof(xfs_dqblk_t));
+	ASSERT(mp->m_quotainfo->qi_dqperchunk == j);
+#endif
+	dqb = bp->b_addr;
+	for (j = 0; j < mp->m_quotainfo->qi_dqperchunk; j++) {
+		struct xfs_disk_dquot	*ddq;
+
+		ddq = (struct xfs_disk_dquot *)&dqb[j];
+
+		/*
+		 * Do a sanity check, and if needed, repair the dqblk. Don't
+		 * output any warnings because it's perfectly possible to
+		 * find uninitialised dquot blks. See comment in xfs_dqcheck.
+		 */
+		xfs_dqcheck(mp, ddq, id+j, type, XFS_QMOPT_DQREPAIR,
+			    "xfs_quotacheck");
+		/*
+		 * Reset type in case we are reusing group quota file for
+		 * project quotas or vice versa
+		 */
+		ddq->d_flags = type;
+		ddq->d_bcount = 0;
+		ddq->d_icount = 0;
+		ddq->d_rtbcount = 0;
+		ddq->d_btimer = 0;
+		ddq->d_itimer = 0;
+		ddq->d_rtbtimer = 0;
+		ddq->d_bwarns = 0;
+		ddq->d_iwarns = 0;
+		ddq->d_rtbwarns = 0;
+
+		if (xfs_sb_version_hascrc(&mp->m_sb)) {
+			xfs_update_cksum((char *)&dqb[j],
+					 sizeof(struct xfs_dqblk),
+					 XFS_DQUOT_CRC_OFF);
+		}
+	}
+}
+
+STATIC int
+xfs_qm_dqiter_bufs(
+	struct xfs_mount	*mp,
+	xfs_dqid_t		firstid,
+	xfs_fsblock_t		bno,
+	xfs_filblks_t		blkcnt,
+	uint			flags,
+	struct list_head	*buffer_list)
+{
+	struct xfs_buf		*bp;
+	int			error;
+	int			type;
+
+	ASSERT(blkcnt > 0);
+	type = flags & XFS_QMOPT_UQUOTA ? XFS_DQ_USER :
+		(flags & XFS_QMOPT_PQUOTA ? XFS_DQ_PROJ : XFS_DQ_GROUP);
+	error = 0;
+
+	/*
+	 * Blkcnt arg can be a very big number, and might even be
+	 * larger than the log itself. So, we have to break it up into
+	 * manageable-sized transactions.
+	 * Note that we don't start a permanent transaction here; we might
+	 * not be able to get a log reservation for the whole thing up front,
+	 * and we don't really care to either, because we just discard
+	 * everything if we were to crash in the middle of this loop.
+	 */
+	while (blkcnt--) {
+		error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
+			      XFS_FSB_TO_DADDR(mp, bno),
+			      mp->m_quotainfo->qi_dqchunklen, 0, &bp,
+			      &xfs_dquot_buf_ops);
+
+		/*
+		 * CRC and validation errors will return a EFSCORRUPTED here. If
+		 * this occurs, re-read without CRC validation so that we can
+		 * repair the damage via xfs_qm_reset_dqcounts(). This process
+		 * will leave a trace in the log indicating corruption has
+		 * been detected.
+		 */
+		if (error == -EFSCORRUPTED) {
+			error = xfs_trans_read_buf(mp, NULL, mp->m_ddev_targp,
+				      XFS_FSB_TO_DADDR(mp, bno),
+				      mp->m_quotainfo->qi_dqchunklen, 0, &bp,
+				      NULL);
+		}
+
+		if (error)
+			break;
+
+		/*
+		 * A corrupt buffer might not have a verifier attached, so
+		 * make sure we have the correct one attached before writeback
+		 * occurs.
+		 */
+		bp->b_ops = &xfs_dquot_buf_ops;
+		xfs_qm_reset_dqcounts(mp, bp, firstid, type);
+		xfs_buf_delwri_queue(bp, buffer_list);
+		xfs_buf_relse(bp);
+
+		/* goto the next block. */
+		bno++;
+		firstid += mp->m_quotainfo->qi_dqperchunk;
+	}
+
+	return error;
+}
+
+/*
+ * Iterate over all allocated USR/GRP/PRJ dquots in the system, calling a
+ * caller supplied function for every chunk of dquots that we find.
+ */
+STATIC int
+xfs_qm_dqiterate(
+	struct xfs_mount	*mp,
+	struct xfs_inode	*qip,
+	uint			flags,
+	struct list_head	*buffer_list)
+{
+	struct xfs_bmbt_irec	*map;
+	int			i, nmaps;	/* number of map entries */
+	int			error;		/* return value */
+	xfs_fileoff_t		lblkno;
+	xfs_filblks_t		maxlblkcnt;
+	xfs_dqid_t		firstid;
+	xfs_fsblock_t		rablkno;
+	xfs_filblks_t		rablkcnt;
+
+	error = 0;
+	/*
+	 * This looks racy, but we can't keep an inode lock across a
+	 * trans_reserve. But, this gets called during quotacheck, and that
+	 * happens only at mount time which is single threaded.
+	 */
+	if (qip->i_d.di_nblocks == 0)
+		return 0;
+
+	map = kmem_alloc(XFS_DQITER_MAP_SIZE * sizeof(*map), KM_SLEEP);
+
+	lblkno = 0;
+	maxlblkcnt = XFS_B_TO_FSB(mp, mp->m_super->s_maxbytes);
+	do {
+		uint		lock_mode;
+
+		nmaps = XFS_DQITER_MAP_SIZE;
+		/*
+		 * We aren't changing the inode itself. Just changing
+		 * some of its data. No new blocks are added here, and
+		 * the inode is never added to the transaction.
+		 */
+		lock_mode = xfs_ilock_data_map_shared(qip);
+		error = xfs_bmapi_read(qip, lblkno, maxlblkcnt - lblkno,
+				       map, &nmaps, 0);
+		xfs_iunlock(qip, lock_mode);
+		if (error)
+			break;
+
+		ASSERT(nmaps <= XFS_DQITER_MAP_SIZE);
+		for (i = 0; i < nmaps; i++) {
+			ASSERT(map[i].br_startblock != DELAYSTARTBLOCK);
+			ASSERT(map[i].br_blockcount);
+
+
+			lblkno += map[i].br_blockcount;
+
+			if (map[i].br_startblock == HOLESTARTBLOCK)
+				continue;
+
+			firstid = (xfs_dqid_t) map[i].br_startoff *
+				mp->m_quotainfo->qi_dqperchunk;
+			/*
+			 * Do a read-ahead on the next extent.
+			 */
+			if ((i+1 < nmaps) &&
+			    (map[i+1].br_startblock != HOLESTARTBLOCK)) {
+				rablkcnt =  map[i+1].br_blockcount;
+				rablkno = map[i+1].br_startblock;
+				while (rablkcnt--) {
+					xfs_buf_readahead(mp->m_ddev_targp,
+					       XFS_FSB_TO_DADDR(mp, rablkno),
+					       mp->m_quotainfo->qi_dqchunklen,
+					       &xfs_dquot_buf_ops);
+					rablkno++;
+				}
+			}
+			/*
+			 * Iterate thru all the blks in the extent and
+			 * reset the counters of all the dquots inside them.
+			 */
+			error = xfs_qm_dqiter_bufs(mp, firstid,
+						   map[i].br_startblock,
+						   map[i].br_blockcount,
+						   flags, buffer_list);
+			if (error)
+				goto out;
+		}
+	} while (nmaps > 0);
+
+out:
+	kmem_free(map);
+	return error;
+}
+
+/*
+ * Called by dqusage_adjust in doing a quotacheck.
+ *
+ * Given the inode, and a dquot id this updates both the incore dqout as well
+ * as the buffer copy. This is so that once the quotacheck is done, we can
+ * just log all the buffers, as opposed to logging numerous updates to
+ * individual dquots.
+ */
+STATIC int
+xfs_qm_quotacheck_dqadjust(
+	struct xfs_inode	*ip,
+	xfs_dqid_t		id,
+	uint			type,
+	xfs_qcnt_t		nblks,
+	xfs_qcnt_t		rtblks)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_dquot	*dqp;
+	int			error;
+
+	error = xfs_qm_dqget(mp, ip, id, type,
+			     XFS_QMOPT_DQALLOC | XFS_QMOPT_DOWARN, &dqp);
+	if (error) {
+		/*
+		 * Shouldn't be able to turn off quotas here.
+		 */
+		ASSERT(error != -ESRCH);
+		ASSERT(error != -ENOENT);
+		return error;
+	}
+
+	trace_xfs_dqadjust(dqp);
+
+	/*
+	 * Adjust the inode count and the block count to reflect this inode's
+	 * resource usage.
+	 */
+	be64_add_cpu(&dqp->q_core.d_icount, 1);
+	dqp->q_res_icount++;
+	if (nblks) {
+		be64_add_cpu(&dqp->q_core.d_bcount, nblks);
+		dqp->q_res_bcount += nblks;
+	}
+	if (rtblks) {
+		be64_add_cpu(&dqp->q_core.d_rtbcount, rtblks);
+		dqp->q_res_rtbcount += rtblks;
+	}
+
+	/*
+	 * Set default limits, adjust timers (since we changed usages)
+	 *
+	 * There are no timers for the default values set in the root dquot.
+	 */
+	if (dqp->q_core.d_id) {
+		xfs_qm_adjust_dqlimits(mp, dqp);
+		xfs_qm_adjust_dqtimers(mp, &dqp->q_core);
+	}
+
+	dqp->dq_flags |= XFS_DQ_DIRTY;
+	xfs_qm_dqput(dqp);
+	return 0;
+}
+
+STATIC int
+xfs_qm_get_rtblks(
+	xfs_inode_t	*ip,
+	xfs_qcnt_t	*O_rtblks)
+{
+	xfs_filblks_t	rtblks;			/* total rt blks */
+	xfs_extnum_t	idx;			/* extent record index */
+	xfs_ifork_t	*ifp;			/* inode fork pointer */
+	xfs_extnum_t	nextents;		/* number of extent entries */
+	int		error;
+
+	ASSERT(XFS_IS_REALTIME_INODE(ip));
+	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
+	if (!(ifp->if_flags & XFS_IFEXTENTS)) {
+		if ((error = xfs_iread_extents(NULL, ip, XFS_DATA_FORK)))
+			return error;
+	}
+	rtblks = 0;
+	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
+	for (idx = 0; idx < nextents; idx++)
+		rtblks += xfs_bmbt_get_blockcount(xfs_iext_get_ext(ifp, idx));
+	*O_rtblks = (xfs_qcnt_t)rtblks;
+	return 0;
+}
+
+/*
+ * callback routine supplied to bulkstat(). Given an inumber, find its
+ * dquots and update them to account for resources taken by that inode.
+ */
+/* ARGSUSED */
+STATIC int
+xfs_qm_dqusage_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)		/* result code value */
+{
+	xfs_inode_t	*ip;
+	xfs_qcnt_t	nblks, rtblks = 0;
+	int		error;
+
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	/*
+	 * rootino must have its resources accounted for, not so with the quota
+	 * inodes.
+	 */
+	if (xfs_is_quota_inode(&mp->m_sb, ino)) {
+		*res = BULKSTAT_RV_NOTHING;
+		return -EINVAL;
+	}
+
+	/*
+	 * We don't _need_ to take the ilock EXCL. However, the xfs_qm_dqget
+	 * interface expects the inode to be exclusively locked because that's
+	 * the case in all other instances. It's OK that we do this because
+	 * quotacheck is done only at mount time.
+	 */
+	error = xfs_iget(mp, NULL, ino, 0, XFS_ILOCK_EXCL, &ip);
+	if (error) {
+		*res = BULKSTAT_RV_NOTHING;
+		return error;
+	}
+
+	ASSERT(ip->i_delayed_blks == 0);
+
+	if (XFS_IS_REALTIME_INODE(ip)) {
+		/*
+		 * Walk thru the extent list and count the realtime blocks.
+		 */
+		error = xfs_qm_get_rtblks(ip, &rtblks);
+		if (error)
+			goto error0;
+	}
+
+	nblks = (xfs_qcnt_t)ip->i_d.di_nblocks - rtblks;
+
+	/*
+	 * Add the (disk blocks and inode) resources occupied by this
+	 * inode to its dquots. We do this adjustment in the incore dquot,
+	 * and also copy the changes to its buffer.
+	 * We don't care about putting these changes in a transaction
+	 * envelope because if we crash in the middle of a 'quotacheck'
+	 * we have to start from the beginning anyway.
+	 * Once we're done, we'll log all the dquot bufs.
+	 *
+	 * The *QUOTA_ON checks below may look pretty racy, but quotachecks
+	 * and quotaoffs don't race. (Quotachecks happen at mount time only).
+	 */
+	if (XFS_IS_UQUOTA_ON(mp)) {
+		error = xfs_qm_quotacheck_dqadjust(ip, ip->i_d.di_uid,
+						   XFS_DQ_USER, nblks, rtblks);
+		if (error)
+			goto error0;
+	}
+
+	if (XFS_IS_GQUOTA_ON(mp)) {
+		error = xfs_qm_quotacheck_dqadjust(ip, ip->i_d.di_gid,
+						   XFS_DQ_GROUP, nblks, rtblks);
+		if (error)
+			goto error0;
+	}
+
+	if (XFS_IS_PQUOTA_ON(mp)) {
+		error = xfs_qm_quotacheck_dqadjust(ip, xfs_get_projid(ip),
+						   XFS_DQ_PROJ, nblks, rtblks);
+		if (error)
+			goto error0;
+	}
+
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	IRELE(ip);
+	*res = BULKSTAT_RV_DIDONE;
+	return 0;
+
+error0:
+	xfs_iunlock(ip, XFS_ILOCK_EXCL);
+	IRELE(ip);
+	*res = BULKSTAT_RV_GIVEUP;
+	return error;
+}
+
+STATIC int
+xfs_qm_flush_one(
+	struct xfs_dquot	*dqp,
+	void			*data)
+{
+	struct list_head	*buffer_list = data;
+	struct xfs_buf		*bp = NULL;
+	int			error = 0;
+
+	xfs_dqlock(dqp);
+	if (dqp->dq_flags & XFS_DQ_FREEING)
+		goto out_unlock;
+	if (!XFS_DQ_IS_DIRTY(dqp))
+		goto out_unlock;
+
+	xfs_dqflock(dqp);
+	error = xfs_qm_dqflush(dqp, &bp);
+	if (error)
+		goto out_unlock;
+
+	xfs_buf_delwri_queue(bp, buffer_list);
+	xfs_buf_relse(bp);
+out_unlock:
+	xfs_dqunlock(dqp);
+	return error;
+}
+
+/*
+ * Walk thru all the filesystem inodes and construct a consistent view
+ * of the disk quota world. If the quotacheck fails, disable quotas.
+ */
+STATIC int
+xfs_qm_quotacheck(
+	xfs_mount_t	*mp)
+{
+	int			done, count, error, error2;
+	xfs_ino_t		lastino;
+	size_t			structsz;
+	uint			flags;
+	LIST_HEAD		(buffer_list);
+	struct xfs_inode	*uip = mp->m_quotainfo->qi_uquotaip;
+	struct xfs_inode	*gip = mp->m_quotainfo->qi_gquotaip;
+	struct xfs_inode	*pip = mp->m_quotainfo->qi_pquotaip;
+
+	count = INT_MAX;
+	structsz = 1;
+	lastino = 0;
+	flags = 0;
+
+	ASSERT(uip || gip || pip);
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	xfs_notice(mp, "Quotacheck needed: Please wait.");
+
+	/*
+	 * First we go thru all the dquots on disk, USR and GRP/PRJ, and reset
+	 * their counters to zero. We need a clean slate.
+	 * We don't log our changes till later.
+	 */
+	if (uip) {
+		error = xfs_qm_dqiterate(mp, uip, XFS_QMOPT_UQUOTA,
+					 &buffer_list);
+		if (error)
+			goto error_return;
+		flags |= XFS_UQUOTA_CHKD;
+	}
+
+	if (gip) {
+		error = xfs_qm_dqiterate(mp, gip, XFS_QMOPT_GQUOTA,
+					 &buffer_list);
+		if (error)
+			goto error_return;
+		flags |= XFS_GQUOTA_CHKD;
+	}
+
+	if (pip) {
+		error = xfs_qm_dqiterate(mp, pip, XFS_QMOPT_PQUOTA,
+					 &buffer_list);
+		if (error)
+			goto error_return;
+		flags |= XFS_PQUOTA_CHKD;
+	}
+
+	do {
+		/*
+		 * Iterate thru all the inodes in the file system,
+		 * adjusting the corresponding dquot counters in core.
+		 */
+		error = xfs_bulkstat(mp, &lastino, &count,
+				     xfs_qm_dqusage_adjust,
+				     structsz, NULL, &done);
+		if (error)
+			break;
+
+	} while (!done);
+
+	/*
+	 * We've made all the changes that we need to make incore.  Flush them
+	 * down to disk buffers if everything was updated successfully.
+	 */
+	if (XFS_IS_UQUOTA_ON(mp)) {
+		error = xfs_qm_dquot_walk(mp, XFS_DQ_USER, xfs_qm_flush_one,
+					  &buffer_list);
+	}
+	if (XFS_IS_GQUOTA_ON(mp)) {
+		error2 = xfs_qm_dquot_walk(mp, XFS_DQ_GROUP, xfs_qm_flush_one,
+					   &buffer_list);
+		if (!error)
+			error = error2;
+	}
+	if (XFS_IS_PQUOTA_ON(mp)) {
+		error2 = xfs_qm_dquot_walk(mp, XFS_DQ_PROJ, xfs_qm_flush_one,
+					   &buffer_list);
+		if (!error)
+			error = error2;
+	}
+
+	error2 = xfs_buf_delwri_submit(&buffer_list);
+	if (!error)
+		error = error2;
+
+	/*
+	 * We can get this error if we couldn't do a dquot allocation inside
+	 * xfs_qm_dqusage_adjust (via bulkstat). We don't care about the
+	 * dirty dquots that might be cached, we just want to get rid of them
+	 * and turn quotaoff. The dquots won't be attached to any of the inodes
+	 * at this point (because we intentionally didn't in dqget_noattach).
+	 */
+	if (error) {
+		xfs_qm_dqpurge_all(mp, XFS_QMOPT_QUOTALL);
+		goto error_return;
+	}
+
+	/*
+	 * If one type of quotas is off, then it will lose its
+	 * quotachecked status, since we won't be doing accounting for
+	 * that type anymore.
+	 */
+	mp->m_qflags &= ~XFS_ALL_QUOTA_CHKD;
+	mp->m_qflags |= flags;
+
+ error_return:
+	while (!list_empty(&buffer_list)) {
+		struct xfs_buf *bp =
+			list_first_entry(&buffer_list, struct xfs_buf, b_list);
+		list_del_init(&bp->b_list);
+		xfs_buf_relse(bp);
+	}
+
+	if (error) {
+		xfs_warn(mp,
+	"Quotacheck: Unsuccessful (Error %d): Disabling quotas.",
+			error);
+		/*
+		 * We must turn off quotas.
+		 */
+		ASSERT(mp->m_quotainfo != NULL);
+		xfs_qm_destroy_quotainfo(mp);
+		if (xfs_mount_reset_sbqflags(mp)) {
+			xfs_warn(mp,
+				"Quotacheck: Failed to reset quota flags.");
+		}
+	} else
+		xfs_notice(mp, "Quotacheck: Done.");
+	return error;
+}
+
+/*
+ * This is called from xfs_mountfs to start quotas and initialize all
+ * necessary data structures like quotainfo.  This is also responsible for
+ * running a quotacheck as necessary.  We are guaranteed that the superblock
+ * is consistently read in at this point.
+ *
+ * If we fail here, the mount will continue with quota turned off. We don't
+ * need to inidicate success or failure at all.
+ */
+void
+xfs_qm_mount_quotas(
+	struct xfs_mount	*mp)
+{
+	int			error = 0;
+	uint			sbf;
+
+	/*
+	 * If quotas on realtime volumes is not supported, we disable
+	 * quotas immediately.
+	 */
+	if (mp->m_sb.sb_rextents) {
+		xfs_notice(mp, "Cannot turn on quotas for realtime filesystem");
+		mp->m_qflags = 0;
+		goto write_changes;
+	}
+
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	/*
+	 * Allocate the quotainfo structure inside the mount struct, and
+	 * create quotainode(s), and change/rev superblock if necessary.
+	 */
+	error = xfs_qm_init_quotainfo(mp);
+	if (error) {
+		/*
+		 * We must turn off quotas.
+		 */
+		ASSERT(mp->m_quotainfo == NULL);
+		mp->m_qflags = 0;
+		goto write_changes;
+	}
+	/*
+	 * If any of the quotas are not consistent, do a quotacheck.
+	 */
+	if (XFS_QM_NEED_QUOTACHECK(mp)) {
+		error = xfs_qm_quotacheck(mp);
+		if (error) {
+			/* Quotacheck failed and disabled quotas. */
+			return;
+		}
+	}
+	/*
+	 * If one type of quotas is off, then it will lose its
+	 * quotachecked status, since we won't be doing accounting for
+	 * that type anymore.
+	 */
+	if (!XFS_IS_UQUOTA_ON(mp))
+		mp->m_qflags &= ~XFS_UQUOTA_CHKD;
+	if (!XFS_IS_GQUOTA_ON(mp))
+		mp->m_qflags &= ~XFS_GQUOTA_CHKD;
+	if (!XFS_IS_PQUOTA_ON(mp))
+		mp->m_qflags &= ~XFS_PQUOTA_CHKD;
+
+ write_changes:
+	/*
+	 * We actually don't have to acquire the m_sb_lock at all.
+	 * This can only be called from mount, and that's single threaded. XXX
+	 */
+	spin_lock(&mp->m_sb_lock);
+	sbf = mp->m_sb.sb_qflags;
+	mp->m_sb.sb_qflags = mp->m_qflags & XFS_MOUNT_QUOTA_ALL;
+	spin_unlock(&mp->m_sb_lock);
+
+	if (sbf != (mp->m_qflags & XFS_MOUNT_QUOTA_ALL)) {
+		if (xfs_sync_sb(mp, false)) {
+			/*
+			 * We could only have been turning quotas off.
+			 * We aren't in very good shape actually because
+			 * the incore structures are convinced that quotas are
+			 * off, but the on disk superblock doesn't know that !
+			 */
+			ASSERT(!(XFS_IS_QUOTA_RUNNING(mp)));
+			xfs_alert(mp, "%s: Superblock update failed!",
+				__func__);
+		}
+	}
+
+	if (error) {
+		xfs_warn(mp, "Failed to initialize disk quotas.");
+		return;
+	}
+}
+
+/*
+ * This is called after the superblock has been read in and we're ready to
+ * iget the quota inodes.
+ */
+STATIC int
+xfs_qm_init_quotainos(
+	xfs_mount_t	*mp)
+{
+	struct xfs_inode	*uip = NULL;
+	struct xfs_inode	*gip = NULL;
+	struct xfs_inode	*pip = NULL;
+	int			error;
+	uint			flags = 0;
+
+	ASSERT(mp->m_quotainfo);
+
+	/*
+	 * Get the uquota and gquota inodes
+	 */
+	if (xfs_sb_version_hasquota(&mp->m_sb)) {
+		if (XFS_IS_UQUOTA_ON(mp) &&
+		    mp->m_sb.sb_uquotino != NULLFSINO) {
+			ASSERT(mp->m_sb.sb_uquotino > 0);
+			error = xfs_iget(mp, NULL, mp->m_sb.sb_uquotino,
+					     0, 0, &uip);
+			if (error)
+				return error;
+		}
+		if (XFS_IS_GQUOTA_ON(mp) &&
+		    mp->m_sb.sb_gquotino != NULLFSINO) {
+			ASSERT(mp->m_sb.sb_gquotino > 0);
+			error = xfs_iget(mp, NULL, mp->m_sb.sb_gquotino,
+					     0, 0, &gip);
+			if (error)
+				goto error_rele;
+		}
+		if (XFS_IS_PQUOTA_ON(mp) &&
+		    mp->m_sb.sb_pquotino != NULLFSINO) {
+			ASSERT(mp->m_sb.sb_pquotino > 0);
+			error = xfs_iget(mp, NULL, mp->m_sb.sb_pquotino,
+					     0, 0, &pip);
+			if (error)
+				goto error_rele;
+		}
+	} else {
+		flags |= XFS_QMOPT_SBVERSION;
+	}
+
+	/*
+	 * Create the three inodes, if they don't exist already. The changes
+	 * made above will get added to a transaction and logged in one of
+	 * the qino_alloc calls below.  If the device is readonly,
+	 * temporarily switch to read-write to do this.
+	 */
+	if (XFS_IS_UQUOTA_ON(mp) && uip == NULL) {
+		error = xfs_qm_qino_alloc(mp, &uip,
+					      flags | XFS_QMOPT_UQUOTA);
+		if (error)
+			goto error_rele;
+
+		flags &= ~XFS_QMOPT_SBVERSION;
+	}
+	if (XFS_IS_GQUOTA_ON(mp) && gip == NULL) {
+		error = xfs_qm_qino_alloc(mp, &gip,
+					  flags | XFS_QMOPT_GQUOTA);
+		if (error)
+			goto error_rele;
+
+		flags &= ~XFS_QMOPT_SBVERSION;
+	}
+	if (XFS_IS_PQUOTA_ON(mp) && pip == NULL) {
+		error = xfs_qm_qino_alloc(mp, &pip,
+					  flags | XFS_QMOPT_PQUOTA);
+		if (error)
+			goto error_rele;
+	}
+
+	mp->m_quotainfo->qi_uquotaip = uip;
+	mp->m_quotainfo->qi_gquotaip = gip;
+	mp->m_quotainfo->qi_pquotaip = pip;
+
+	return 0;
+
+error_rele:
+	if (uip)
+		IRELE(uip);
+	if (gip)
+		IRELE(gip);
+	if (pip)
+		IRELE(pip);
+	return error;
+}
+
+STATIC void
+xfs_qm_dqfree_one(
+	struct xfs_dquot	*dqp)
+{
+	struct xfs_mount	*mp = dqp->q_mount;
+	struct xfs_quotainfo	*qi = mp->m_quotainfo;
+
+	mutex_lock(&qi->qi_tree_lock);
+	radix_tree_delete(xfs_dquot_tree(qi, dqp->q_core.d_flags),
+			  be32_to_cpu(dqp->q_core.d_id));
+
+	qi->qi_dquots--;
+	mutex_unlock(&qi->qi_tree_lock);
+
+	xfs_qm_dqdestroy(dqp);
+}
+
+/* --------------- utility functions for vnodeops ---------------- */
+
+
+/*
+ * Given an inode, a uid, gid and prid make sure that we have
+ * allocated relevant dquot(s) on disk, and that we won't exceed inode
+ * quotas by creating this file.
+ * This also attaches dquot(s) to the given inode after locking it,
+ * and returns the dquots corresponding to the uid and/or gid.
+ *
+ * in	: inode (unlocked)
+ * out	: udquot, gdquot with references taken and unlocked
+ */
+int
+xfs_qm_vop_dqalloc(
+	struct xfs_inode	*ip,
+	xfs_dqid_t		uid,
+	xfs_dqid_t		gid,
+	prid_t			prid,
+	uint			flags,
+	struct xfs_dquot	**O_udqpp,
+	struct xfs_dquot	**O_gdqpp,
+	struct xfs_dquot	**O_pdqpp)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	struct xfs_dquot	*uq = NULL;
+	struct xfs_dquot	*gq = NULL;
+	struct xfs_dquot	*pq = NULL;
+	int			error;
+	uint			lockflags;
+
+	if (!XFS_IS_QUOTA_RUNNING(mp) || !XFS_IS_QUOTA_ON(mp))
+		return 0;
+
+	lockflags = XFS_ILOCK_EXCL;
+	xfs_ilock(ip, lockflags);
+
+	if ((flags & XFS_QMOPT_INHERIT) && XFS_INHERIT_GID(ip))
+		gid = ip->i_d.di_gid;
+
+	/*
+	 * Attach the dquot(s) to this inode, doing a dquot allocation
+	 * if necessary. The dquot(s) will not be locked.
+	 */
+	if (XFS_NOT_DQATTACHED(mp, ip)) {
+		error = xfs_qm_dqattach_locked(ip, XFS_QMOPT_DQALLOC);
+		if (error) {
+			xfs_iunlock(ip, lockflags);
+			return error;
+		}
+	}
+
+	if ((flags & XFS_QMOPT_UQUOTA) && XFS_IS_UQUOTA_ON(mp)) {
+		if (ip->i_d.di_uid != uid) {
+			/*
+			 * What we need is the dquot that has this uid, and
+			 * if we send the inode to dqget, the uid of the inode
+			 * takes priority over what's sent in the uid argument.
+			 * We must unlock inode here before calling dqget if
+			 * we're not sending the inode, because otherwise
+			 * we'll deadlock by doing trans_reserve while
+			 * holding ilock.
+			 */
+			xfs_iunlock(ip, lockflags);
+			error = xfs_qm_dqget(mp, NULL, uid,
+						 XFS_DQ_USER,
+						 XFS_QMOPT_DQALLOC |
+						 XFS_QMOPT_DOWARN,
+						 &uq);
+			if (error) {
+				ASSERT(error != -ENOENT);
+				return error;
+			}
+			/*
+			 * Get the ilock in the right order.
+			 */
+			xfs_dqunlock(uq);
+			lockflags = XFS_ILOCK_SHARED;
+			xfs_ilock(ip, lockflags);
+		} else {
+			/*
+			 * Take an extra reference, because we'll return
+			 * this to caller
+			 */
+			ASSERT(ip->i_udquot);
+			uq = xfs_qm_dqhold(ip->i_udquot);
+		}
+	}
+	if ((flags & XFS_QMOPT_GQUOTA) && XFS_IS_GQUOTA_ON(mp)) {
+		if (ip->i_d.di_gid != gid) {
+			xfs_iunlock(ip, lockflags);
+			error = xfs_qm_dqget(mp, NULL, gid,
+						 XFS_DQ_GROUP,
+						 XFS_QMOPT_DQALLOC |
+						 XFS_QMOPT_DOWARN,
+						 &gq);
+			if (error) {
+				ASSERT(error != -ENOENT);
+				goto error_rele;
+			}
+			xfs_dqunlock(gq);
+			lockflags = XFS_ILOCK_SHARED;
+			xfs_ilock(ip, lockflags);
+		} else {
+			ASSERT(ip->i_gdquot);
+			gq = xfs_qm_dqhold(ip->i_gdquot);
+		}
+	}
+	if ((flags & XFS_QMOPT_PQUOTA) && XFS_IS_PQUOTA_ON(mp)) {
+		if (xfs_get_projid(ip) != prid) {
+			xfs_iunlock(ip, lockflags);
+			error = xfs_qm_dqget(mp, NULL, (xfs_dqid_t)prid,
+						 XFS_DQ_PROJ,
+						 XFS_QMOPT_DQALLOC |
+						 XFS_QMOPT_DOWARN,
+						 &pq);
+			if (error) {
+				ASSERT(error != -ENOENT);
+				goto error_rele;
+			}
+			xfs_dqunlock(pq);
+			lockflags = XFS_ILOCK_SHARED;
+			xfs_ilock(ip, lockflags);
+		} else {
+			ASSERT(ip->i_pdquot);
+			pq = xfs_qm_dqhold(ip->i_pdquot);
+		}
+	}
+	if (uq)
+		trace_xfs_dquot_dqalloc(ip);
+
+	xfs_iunlock(ip, lockflags);
+	if (O_udqpp)
+		*O_udqpp = uq;
+	else
+		xfs_qm_dqrele(uq);
+	if (O_gdqpp)
+		*O_gdqpp = gq;
+	else
+		xfs_qm_dqrele(gq);
+	if (O_pdqpp)
+		*O_pdqpp = pq;
+	else
+		xfs_qm_dqrele(pq);
+	return 0;
+
+error_rele:
+	xfs_qm_dqrele(gq);
+	xfs_qm_dqrele(uq);
+	return error;
+}
+
+/*
+ * Actually transfer ownership, and do dquot modifications.
+ * These were already reserved.
+ */
+xfs_dquot_t *
+xfs_qm_vop_chown(
+	xfs_trans_t	*tp,
+	xfs_inode_t	*ip,
+	xfs_dquot_t	**IO_olddq,
+	xfs_dquot_t	*newdq)
+{
+	xfs_dquot_t	*prevdq;
+	uint		bfield = XFS_IS_REALTIME_INODE(ip) ?
+				 XFS_TRANS_DQ_RTBCOUNT : XFS_TRANS_DQ_BCOUNT;
+
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+	ASSERT(XFS_IS_QUOTA_RUNNING(ip->i_mount));
+
+	/* old dquot */
+	prevdq = *IO_olddq;
+	ASSERT(prevdq);
+	ASSERT(prevdq != newdq);
+
+	xfs_trans_mod_dquot(tp, prevdq, bfield, -(ip->i_d.di_nblocks));
+	xfs_trans_mod_dquot(tp, prevdq, XFS_TRANS_DQ_ICOUNT, -1);
+
+	/* the sparkling new dquot */
+	xfs_trans_mod_dquot(tp, newdq, bfield, ip->i_d.di_nblocks);
+	xfs_trans_mod_dquot(tp, newdq, XFS_TRANS_DQ_ICOUNT, 1);
+
+	/*
+	 * Take an extra reference, because the inode is going to keep
+	 * this dquot pointer even after the trans_commit.
+	 */
+	*IO_olddq = xfs_qm_dqhold(newdq);
+
+	return prevdq;
+}
+
+/*
+ * Quota reservations for setattr(AT_UID|AT_GID|AT_PROJID).
+ */
+int
+xfs_qm_vop_chown_reserve(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip,
+	struct xfs_dquot	*udqp,
+	struct xfs_dquot	*gdqp,
+	struct xfs_dquot	*pdqp,
+	uint			flags)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+	uint			delblks, blkflags, prjflags = 0;
+	struct xfs_dquot	*udq_unres = NULL;
+	struct xfs_dquot	*gdq_unres = NULL;
+	struct xfs_dquot	*pdq_unres = NULL;
+	struct xfs_dquot	*udq_delblks = NULL;
+	struct xfs_dquot	*gdq_delblks = NULL;
+	struct xfs_dquot	*pdq_delblks = NULL;
+	int			error;
+
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	delblks = ip->i_delayed_blks;
+	blkflags = XFS_IS_REALTIME_INODE(ip) ?
+			XFS_QMOPT_RES_RTBLKS : XFS_QMOPT_RES_REGBLKS;
+
+	if (XFS_IS_UQUOTA_ON(mp) && udqp &&
+	    ip->i_d.di_uid != be32_to_cpu(udqp->q_core.d_id)) {
+		udq_delblks = udqp;
+		/*
+		 * If there are delayed allocation blocks, then we have to
+		 * unreserve those from the old dquot, and add them to the
+		 * new dquot.
+		 */
+		if (delblks) {
+			ASSERT(ip->i_udquot);
+			udq_unres = ip->i_udquot;
+		}
+	}
+	if (XFS_IS_GQUOTA_ON(ip->i_mount) && gdqp &&
+	    ip->i_d.di_gid != be32_to_cpu(gdqp->q_core.d_id)) {
+		gdq_delblks = gdqp;
+		if (delblks) {
+			ASSERT(ip->i_gdquot);
+			gdq_unres = ip->i_gdquot;
+		}
+	}
+
+	if (XFS_IS_PQUOTA_ON(ip->i_mount) && pdqp &&
+	    xfs_get_projid(ip) != be32_to_cpu(pdqp->q_core.d_id)) {
+		prjflags = XFS_QMOPT_ENOSPC;
+		pdq_delblks = pdqp;
+		if (delblks) {
+			ASSERT(ip->i_pdquot);
+			pdq_unres = ip->i_pdquot;
+		}
+	}
+
+	error = xfs_trans_reserve_quota_bydquots(tp, ip->i_mount,
+				udq_delblks, gdq_delblks, pdq_delblks,
+				ip->i_d.di_nblocks, 1,
+				flags | blkflags | prjflags);
+	if (error)
+		return error;
+
+	/*
+	 * Do the delayed blks reservations/unreservations now. Since, these
+	 * are done without the help of a transaction, if a reservation fails
+	 * its previous reservations won't be automatically undone by trans
+	 * code. So, we have to do it manually here.
+	 */
+	if (delblks) {
+		/*
+		 * Do the reservations first. Unreservation can't fail.
+		 */
+		ASSERT(udq_delblks || gdq_delblks || pdq_delblks);
+		ASSERT(udq_unres || gdq_unres || pdq_unres);
+		error = xfs_trans_reserve_quota_bydquots(NULL, ip->i_mount,
+			    udq_delblks, gdq_delblks, pdq_delblks,
+			    (xfs_qcnt_t)delblks, 0,
+			    flags | blkflags | prjflags);
+		if (error)
+			return error;
+		xfs_trans_reserve_quota_bydquots(NULL, ip->i_mount,
+				udq_unres, gdq_unres, pdq_unres,
+				-((xfs_qcnt_t)delblks), 0, blkflags);
+	}
+
+	return 0;
+}
+
+int
+xfs_qm_vop_rename_dqattach(
+	struct xfs_inode	**i_tab)
+{
+	struct xfs_mount	*mp = i_tab[0]->i_mount;
+	int			i;
+
+	if (!XFS_IS_QUOTA_RUNNING(mp) || !XFS_IS_QUOTA_ON(mp))
+		return 0;
+
+	for (i = 0; (i < 4 && i_tab[i]); i++) {
+		struct xfs_inode	*ip = i_tab[i];
+		int			error;
+
+		/*
+		 * Watch out for duplicate entries in the table.
+		 */
+		if (i == 0 || ip != i_tab[i-1]) {
+			if (XFS_NOT_DQATTACHED(mp, ip)) {
+				error = xfs_qm_dqattach(ip, 0);
+				if (error)
+					return error;
+			}
+		}
+	}
+	return 0;
+}
+
+void
+xfs_qm_vop_create_dqattach(
+	struct xfs_trans	*tp,
+	struct xfs_inode	*ip,
+	struct xfs_dquot	*udqp,
+	struct xfs_dquot	*gdqp,
+	struct xfs_dquot	*pdqp)
+{
+	struct xfs_mount	*mp = tp->t_mountp;
+
+	if (!XFS_IS_QUOTA_RUNNING(mp) || !XFS_IS_QUOTA_ON(mp))
+		return;
+
+	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
+	ASSERT(XFS_IS_QUOTA_RUNNING(mp));
+
+	if (udqp && XFS_IS_UQUOTA_ON(mp)) {
+		ASSERT(ip->i_udquot == NULL);
+		ASSERT(ip->i_d.di_uid == be32_to_cpu(udqp->q_core.d_id));
+
+		ip->i_udquot = xfs_qm_dqhold(udqp);
+		xfs_trans_mod_dquot(tp, udqp, XFS_TRANS_DQ_ICOUNT, 1);
+	}
+	if (gdqp && XFS_IS_GQUOTA_ON(mp)) {
+		ASSERT(ip->i_gdquot == NULL);
+		ASSERT(ip->i_d.di_gid == be32_to_cpu(gdqp->q_core.d_id));
+		ip->i_gdquot = xfs_qm_dqhold(gdqp);
+		xfs_trans_mod_dquot(tp, gdqp, XFS_TRANS_DQ_ICOUNT, 1);
+	}
+	if (pdqp && XFS_IS_PQUOTA_ON(mp)) {
+		ASSERT(ip->i_pdquot == NULL);
+		ASSERT(xfs_get_projid(ip) == be32_to_cpu(pdqp->q_core.d_id));
+
+		ip->i_pdquot = xfs_qm_dqhold(pdqp);
+		xfs_trans_mod_dquot(tp, pdqp, XFS_TRANS_DQ_ICOUNT, 1);
+	}
+}
+