quota: Move quota files into separate directory

Quota subsystem has more and more files. It's time to create a dir for it.

Signed-off-by: Jan Kara <jack@suse.cz>

10 files changed, 4367 insertions, 0 deletions

diff --git a/fs/quota/Kconfig b/fs/quota/Kconfig
new file mode 100644
index 00000000000..d9750d86fde
--- /dev/null
+++ b/fs/quota/Kconfig
@@ -0,0 +1,59 @@
+#
+#  Quota configuration
+#
+
+config QUOTA
+	bool "Quota support"
+	help
+	  If you say Y here, you will be able to set per user limits for disk
+	  usage (also called disk quotas). Currently, it works for the
+	  ext2, ext3, and reiserfs file system. ext3 also supports journalled
+	  quotas for which you don't need to run quotacheck(8) after an unclean
+	  shutdown.
+	  For further details, read the Quota mini-HOWTO, available from
+	  <http://www.tldp.org/docs.html#howto>, or the documentation provided
+	  with the quota tools. Probably the quota support is only useful for
+	  multi user systems. If unsure, say N.
+
+config QUOTA_NETLINK_INTERFACE
+	bool "Report quota messages through netlink interface"
+	depends on QUOTA && NET
+	help
+	  If you say Y here, quota warnings (about exceeding softlimit, reaching
+	  hardlimit, etc.) will be reported through netlink interface. If unsure,
+	  say Y.
+
+config PRINT_QUOTA_WARNING
+	bool "Print quota warnings to console (OBSOLETE)"
+	depends on QUOTA
+	default y
+	help
+	  If you say Y here, quota warnings (about exceeding softlimit, reaching
+	  hardlimit, etc.) will be printed to the process' controlling terminal.
+	  Note that this behavior is currently deprecated and may go away in
+	  future. Please use notification via netlink socket instead.
+
+# Generic support for tree structured quota files. Seleted when needed.
+config QUOTA_TREE
+	 tristate
+
+config QFMT_V1
+	tristate "Old quota format support"
+	depends on QUOTA
+	help
+	  This quota format was (is) used by kernels earlier than 2.4.22. If
+	  you have quota working and you don't want to convert to new quota
+	  format say Y here.
+
+config QFMT_V2
+	tristate "Quota format v2 support"
+	depends on QUOTA
+	select QUOTA_TREE
+	help
+	  This quota format allows using quotas with 32-bit UIDs/GIDs. If you
+	  need this functionality say Y here.
+
+config QUOTACTL
+	bool
+	depends on XFS_QUOTA || QUOTA
+	default y
diff --git a/fs/quota/Makefile b/fs/quota/Makefile
new file mode 100644
index 00000000000..385a0831cc9
--- /dev/null
+++ b/fs/quota/Makefile
@@ -0,0 +1,14 @@
+#
+# Makefile for the Linux filesystems.
+#
+# 14 Sep 2000, Christoph Hellwig <hch@infradead.org>
+# Rewritten to use lists instead of if-statements.
+#
+
+obj-y :=
+
+obj-$(CONFIG_QUOTA)		+= dquot.o
+obj-$(CONFIG_QFMT_V1)		+= quota_v1.o
+obj-$(CONFIG_QFMT_V2)		+= quota_v2.o
+obj-$(CONFIG_QUOTA_TREE)	+= quota_tree.o
+obj-$(CONFIG_QUOTACTL)		+= quota.o
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
new file mode 100644
index 00000000000..28aa1466760
--- /dev/null
+++ b/fs/quota/dquot.c
@@ -0,0 +1,2564 @@
+/*
+ * Implementation of the diskquota system for the LINUX operating system. QUOTA
+ * is implemented using the BSD system call interface as the means of
+ * communication with the user level. This file contains the generic routines
+ * called by the different filesystems on allocation of an inode or block.
+ * These routines take care of the administration needed to have a consistent
+ * diskquota tracking system. The ideas of both user and group quotas are based
+ * on the Melbourne quota system as used on BSD derived systems. The internal
+ * implementation is based on one of the several variants of the LINUX
+ * inode-subsystem with added complexity of the diskquota system.
+ * 
+ * Author:	Marco van Wieringen <mvw@planets.elm.net>
+ *
+ * Fixes:   Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
+ *
+ *		Revised list management to avoid races
+ *		-- Bill Hawes, <whawes@star.net>, 9/98
+ *
+ *		Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
+ *		As the consequence the locking was moved from dquot_decr_...(),
+ *		dquot_incr_...() to calling functions.
+ *		invalidate_dquots() now writes modified dquots.
+ *		Serialized quota_off() and quota_on() for mount point.
+ *		Fixed a few bugs in grow_dquots().
+ *		Fixed deadlock in write_dquot() - we no longer account quotas on
+ *		quota files
+ *		remove_dquot_ref() moved to inode.c - it now traverses through inodes
+ *		add_dquot_ref() restarts after blocking
+ *		Added check for bogus uid and fixed check for group in quotactl.
+ *		Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
+ *
+ *		Used struct list_head instead of own list struct
+ *		Invalidation of referenced dquots is no longer possible
+ *		Improved free_dquots list management
+ *		Quota and i_blocks are now updated in one place to avoid races
+ *		Warnings are now delayed so we won't block in critical section
+ *		Write updated not to require dquot lock
+ *		Jan Kara, <jack@suse.cz>, 9/2000
+ *
+ *		Added dynamic quota structure allocation
+ *		Jan Kara <jack@suse.cz> 12/2000
+ *
+ *		Rewritten quota interface. Implemented new quota format and
+ *		formats registering.
+ *		Jan Kara, <jack@suse.cz>, 2001,2002
+ *
+ *		New SMP locking.
+ *		Jan Kara, <jack@suse.cz>, 10/2002
+ *
+ *		Added journalled quota support, fix lock inversion problems
+ *		Jan Kara, <jack@suse.cz>, 2003,2004
+ *
+ * (C) Copyright 1994 - 1997 Marco van Wieringen 
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/mm.h>
+#include <linux/time.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/stat.h>
+#include <linux/tty.h>
+#include <linux/file.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/proc_fs.h>
+#include <linux/security.h>
+#include <linux/kmod.h>
+#include <linux/namei.h>
+#include <linux/buffer_head.h>
+#include <linux/capability.h>
+#include <linux/quotaops.h>
+#include <linux/writeback.h> /* for inode_lock, oddly enough.. */
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+#include <net/netlink.h>
+#include <net/genetlink.h>
+#endif
+
+#include <asm/uaccess.h>
+
+#define __DQUOT_PARANOIA
+
+/*
+ * There are three quota SMP locks. dq_list_lock protects all lists with quotas
+ * and quota formats, dqstats structure containing statistics about the lists
+ * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
+ * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
+ * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
+ * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
+ * modifications of quota state (on quotaon and quotaoff) and readers who care
+ * about latest values take it as well.
+ *
+ * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
+ *   dq_list_lock > dq_state_lock
+ *
+ * Note that some things (eg. sb pointer, type, id) doesn't change during
+ * the life of the dquot structure and so needn't to be protected by a lock
+ *
+ * Any operation working on dquots via inode pointers must hold dqptr_sem.  If
+ * operation is just reading pointers from inode (or not using them at all) the
+ * read lock is enough. If pointers are altered function must hold write lock
+ * (these locking rules also apply for S_NOQUOTA flag in the inode - note that
+ * for altering the flag i_mutex is also needed).
+ *
+ * Each dquot has its dq_lock mutex. Locked dquots might not be referenced
+ * from inodes (dquot_alloc_space() and such don't check the dq_lock).
+ * Currently dquot is locked only when it is being read to memory (or space for
+ * it is being allocated) on the first dqget() and when it is being released on
+ * the last dqput(). The allocation and release oparations are serialized by
+ * the dq_lock and by checking the use count in dquot_release().  Write
+ * operations on dquots don't hold dq_lock as they copy data under dq_data_lock
+ * spinlock to internal buffers before writing.
+ *
+ * Lock ordering (including related VFS locks) is the following:
+ *   i_mutex > dqonoff_sem > journal_lock > dqptr_sem > dquot->dq_lock >
+ *   dqio_mutex
+ * The lock ordering of dqptr_sem imposed by quota code is only dqonoff_sem >
+ * dqptr_sem. But filesystem has to count with the fact that functions such as
+ * dquot_alloc_space() acquire dqptr_sem and they usually have to be called
+ * from inside a transaction to keep filesystem consistency after a crash. Also
+ * filesystems usually want to do some IO on dquot from ->mark_dirty which is
+ * called with dqptr_sem held.
+ * i_mutex on quota files is special (it's below dqio_mutex)
+ */
+
+static DEFINE_SPINLOCK(dq_list_lock);
+static DEFINE_SPINLOCK(dq_state_lock);
+DEFINE_SPINLOCK(dq_data_lock);
+EXPORT_SYMBOL(dq_data_lock);
+
+static char *quotatypes[] = INITQFNAMES;
+static struct quota_format_type *quota_formats;	/* List of registered formats */
+static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
+
+/* SLAB cache for dquot structures */
+static struct kmem_cache *dquot_cachep;
+
+int register_quota_format(struct quota_format_type *fmt)
+{
+	spin_lock(&dq_list_lock);
+	fmt->qf_next = quota_formats;
+	quota_formats = fmt;
+	spin_unlock(&dq_list_lock);
+	return 0;
+}
+EXPORT_SYMBOL(register_quota_format);
+
+void unregister_quota_format(struct quota_format_type *fmt)
+{
+	struct quota_format_type **actqf;
+
+	spin_lock(&dq_list_lock);
+	for (actqf = &quota_formats; *actqf && *actqf != fmt; actqf = &(*actqf)->qf_next);
+	if (*actqf)
+		*actqf = (*actqf)->qf_next;
+	spin_unlock(&dq_list_lock);
+}
+EXPORT_SYMBOL(unregister_quota_format);
+
+static struct quota_format_type *find_quota_format(int id)
+{
+	struct quota_format_type *actqf;
+
+	spin_lock(&dq_list_lock);
+	for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
+	if (!actqf || !try_module_get(actqf->qf_owner)) {
+		int qm;
+
+		spin_unlock(&dq_list_lock);
+		
+		for (qm = 0; module_names[qm].qm_fmt_id && module_names[qm].qm_fmt_id != id; qm++);
+		if (!module_names[qm].qm_fmt_id || request_module(module_names[qm].qm_mod_name))
+			return NULL;
+
+		spin_lock(&dq_list_lock);
+		for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id; actqf = actqf->qf_next);
+		if (actqf && !try_module_get(actqf->qf_owner))
+			actqf = NULL;
+	}
+	spin_unlock(&dq_list_lock);
+	return actqf;
+}
+
+static void put_quota_format(struct quota_format_type *fmt)
+{
+	module_put(fmt->qf_owner);
+}
+
+/*
+ * Dquot List Management:
+ * The quota code uses three lists for dquot management: the inuse_list,
+ * free_dquots, and dquot_hash[] array. A single dquot structure may be
+ * on all three lists, depending on its current state.
+ *
+ * All dquots are placed to the end of inuse_list when first created, and this
+ * list is used for invalidate operation, which must look at every dquot.
+ *
+ * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
+ * and this list is searched whenever we need an available dquot.  Dquots are
+ * removed from the list as soon as they are used again, and
+ * dqstats.free_dquots gives the number of dquots on the list. When
+ * dquot is invalidated it's completely released from memory.
+ *
+ * Dquots with a specific identity (device, type and id) are placed on
+ * one of the dquot_hash[] hash chains. The provides an efficient search
+ * mechanism to locate a specific dquot.
+ */
+
+static LIST_HEAD(inuse_list);
+static LIST_HEAD(free_dquots);
+static unsigned int dq_hash_bits, dq_hash_mask;
+static struct hlist_head *dquot_hash;
+
+struct dqstats dqstats;
+EXPORT_SYMBOL(dqstats);
+
+static inline unsigned int
+hashfn(const struct super_block *sb, unsigned int id, int type)
+{
+	unsigned long tmp;
+
+	tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
+	return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
+}
+
+/*
+ * Following list functions expect dq_list_lock to be held
+ */
+static inline void insert_dquot_hash(struct dquot *dquot)
+{
+	struct hlist_head *head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id, dquot->dq_type);
+	hlist_add_head(&dquot->dq_hash, head);
+}
+
+static inline void remove_dquot_hash(struct dquot *dquot)
+{
+	hlist_del_init(&dquot->dq_hash);
+}
+
+static inline struct dquot *find_dquot(unsigned int hashent, struct super_block *sb, unsigned int id, int type)
+{
+	struct hlist_node *node;
+	struct dquot *dquot;
+
+	hlist_for_each (node, dquot_hash+hashent) {
+		dquot = hlist_entry(node, struct dquot, dq_hash);
+		if (dquot->dq_sb == sb && dquot->dq_id == id && dquot->dq_type == type)
+			return dquot;
+	}
+	return NODQUOT;
+}
+
+/* Add a dquot to the tail of the free list */
+static inline void put_dquot_last(struct dquot *dquot)
+{
+	list_add_tail(&dquot->dq_free, &free_dquots);
+	dqstats.free_dquots++;
+}
+
+static inline void remove_free_dquot(struct dquot *dquot)
+{
+	if (list_empty(&dquot->dq_free))
+		return;
+	list_del_init(&dquot->dq_free);
+	dqstats.free_dquots--;
+}
+
+static inline void put_inuse(struct dquot *dquot)
+{
+	/* We add to the back of inuse list so we don't have to restart
+	 * when traversing this list and we block */
+	list_add_tail(&dquot->dq_inuse, &inuse_list);
+	dqstats.allocated_dquots++;
+}
+
+static inline void remove_inuse(struct dquot *dquot)
+{
+	dqstats.allocated_dquots--;
+	list_del(&dquot->dq_inuse);
+}
+/*
+ * End of list functions needing dq_list_lock
+ */
+
+static void wait_on_dquot(struct dquot *dquot)
+{
+	mutex_lock(&dquot->dq_lock);
+	mutex_unlock(&dquot->dq_lock);
+}
+
+static inline int dquot_dirty(struct dquot *dquot)
+{
+	return test_bit(DQ_MOD_B, &dquot->dq_flags);
+}
+
+static inline int mark_dquot_dirty(struct dquot *dquot)
+{
+	return dquot->dq_sb->dq_op->mark_dirty(dquot);
+}
+
+int dquot_mark_dquot_dirty(struct dquot *dquot)
+{
+	spin_lock(&dq_list_lock);
+	if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags))
+		list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
+				info[dquot->dq_type].dqi_dirty_list);
+	spin_unlock(&dq_list_lock);
+	return 0;
+}
+EXPORT_SYMBOL(dquot_mark_dquot_dirty);
+
+/* This function needs dq_list_lock */
+static inline int clear_dquot_dirty(struct dquot *dquot)
+{
+	if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags))
+		return 0;
+	list_del_init(&dquot->dq_dirty);
+	return 1;
+}
+
+void mark_info_dirty(struct super_block *sb, int type)
+{
+	set_bit(DQF_INFO_DIRTY_B, &sb_dqopt(sb)->info[type].dqi_flags);
+}
+EXPORT_SYMBOL(mark_info_dirty);
+
+/*
+ *	Read dquot from disk and alloc space for it
+ */
+
+int dquot_acquire(struct dquot *dquot)
+{
+	int ret = 0, ret2 = 0;
+	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+	mutex_lock(&dquot->dq_lock);
+	mutex_lock(&dqopt->dqio_mutex);
+	if (!test_bit(DQ_READ_B, &dquot->dq_flags))
+		ret = dqopt->ops[dquot->dq_type]->read_dqblk(dquot);
+	if (ret < 0)
+		goto out_iolock;
+	set_bit(DQ_READ_B, &dquot->dq_flags);
+	/* Instantiate dquot if needed */
+	if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
+		ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
+		/* Write the info if needed */
+		if (info_dirty(&dqopt->info[dquot->dq_type]))
+			ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
+		if (ret < 0)
+			goto out_iolock;
+		if (ret2 < 0) {
+			ret = ret2;
+			goto out_iolock;
+		}
+	}
+	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
+out_iolock:
+	mutex_unlock(&dqopt->dqio_mutex);
+	mutex_unlock(&dquot->dq_lock);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_acquire);
+
+/*
+ *	Write dquot to disk
+ */
+int dquot_commit(struct dquot *dquot)
+{
+	int ret = 0, ret2 = 0;
+	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+	mutex_lock(&dqopt->dqio_mutex);
+	spin_lock(&dq_list_lock);
+	if (!clear_dquot_dirty(dquot)) {
+		spin_unlock(&dq_list_lock);
+		goto out_sem;
+	}
+	spin_unlock(&dq_list_lock);
+	/* Inactive dquot can be only if there was error during read/init
+	 * => we have better not writing it */
+	if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+		ret = dqopt->ops[dquot->dq_type]->commit_dqblk(dquot);
+		if (info_dirty(&dqopt->info[dquot->dq_type]))
+			ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
+		if (ret >= 0)
+			ret = ret2;
+	}
+out_sem:
+	mutex_unlock(&dqopt->dqio_mutex);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_commit);
+
+/*
+ *	Release dquot
+ */
+int dquot_release(struct dquot *dquot)
+{
+	int ret = 0, ret2 = 0;
+	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+
+	mutex_lock(&dquot->dq_lock);
+	/* Check whether we are not racing with some other dqget() */
+	if (atomic_read(&dquot->dq_count) > 1)
+		goto out_dqlock;
+	mutex_lock(&dqopt->dqio_mutex);
+	if (dqopt->ops[dquot->dq_type]->release_dqblk) {
+		ret = dqopt->ops[dquot->dq_type]->release_dqblk(dquot);
+		/* Write the info */
+		if (info_dirty(&dqopt->info[dquot->dq_type]))
+			ret2 = dqopt->ops[dquot->dq_type]->write_file_info(dquot->dq_sb, dquot->dq_type);
+		if (ret >= 0)
+			ret = ret2;
+	}
+	clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
+	mutex_unlock(&dqopt->dqio_mutex);
+out_dqlock:
+	mutex_unlock(&dquot->dq_lock);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_release);
+
+void dquot_destroy(struct dquot *dquot)
+{
+	kmem_cache_free(dquot_cachep, dquot);
+}
+EXPORT_SYMBOL(dquot_destroy);
+
+static inline void do_destroy_dquot(struct dquot *dquot)
+{
+	dquot->dq_sb->dq_op->destroy_dquot(dquot);
+}
+
+/* Invalidate all dquots on the list. Note that this function is called after
+ * quota is disabled and pointers from inodes removed so there cannot be new
+ * quota users. There can still be some users of quotas due to inodes being
+ * just deleted or pruned by prune_icache() (those are not attached to any
+ * list) or parallel quotactl call. We have to wait for such users.
+ */
+static void invalidate_dquots(struct super_block *sb, int type)
+{
+	struct dquot *dquot, *tmp;
+
+restart:
+	spin_lock(&dq_list_lock);
+	list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
+		if (dquot->dq_sb != sb)
+			continue;
+		if (dquot->dq_type != type)
+			continue;
+		/* Wait for dquot users */
+		if (atomic_read(&dquot->dq_count)) {
+			DEFINE_WAIT(wait);
+
+			atomic_inc(&dquot->dq_count);
+			prepare_to_wait(&dquot->dq_wait_unused, &wait,
+					TASK_UNINTERRUPTIBLE);
+			spin_unlock(&dq_list_lock);
+			/* Once dqput() wakes us up, we know it's time to free
+			 * the dquot.
+			 * IMPORTANT: we rely on the fact that there is always
+			 * at most one process waiting for dquot to free.
+			 * Otherwise dq_count would be > 1 and we would never
+			 * wake up.
+			 */
+			if (atomic_read(&dquot->dq_count) > 1)
+				schedule();
+			finish_wait(&dquot->dq_wait_unused, &wait);
+			dqput(dquot);
+			/* At this moment dquot() need not exist (it could be
+			 * reclaimed by prune_dqcache(). Hence we must
+			 * restart. */
+			goto restart;
+		}
+		/*
+		 * Quota now has no users and it has been written on last
+		 * dqput()
+		 */
+		remove_dquot_hash(dquot);
+		remove_free_dquot(dquot);
+		remove_inuse(dquot);
+		do_destroy_dquot(dquot);
+	}
+	spin_unlock(&dq_list_lock);
+}
+
+/* Call callback for every active dquot on given filesystem */
+int dquot_scan_active(struct super_block *sb,
+		      int (*fn)(struct dquot *dquot, unsigned long priv),
+		      unsigned long priv)
+{
+	struct dquot *dquot, *old_dquot = NULL;
+	int ret = 0;
+
+	mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+	spin_lock(&dq_list_lock);
+	list_for_each_entry(dquot, &inuse_list, dq_inuse) {
+		if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
+			continue;
+		if (dquot->dq_sb != sb)
+			continue;
+		/* Now we have active dquot so we can just increase use count */
+		atomic_inc(&dquot->dq_count);
+		dqstats.lookups++;
+		spin_unlock(&dq_list_lock);
+		dqput(old_dquot);
+		old_dquot = dquot;
+		ret = fn(dquot, priv);
+		if (ret < 0)
+			goto out;
+		spin_lock(&dq_list_lock);
+		/* We are safe to continue now because our dquot could not
+		 * be moved out of the inuse list while we hold the reference */
+	}
+	spin_unlock(&dq_list_lock);
+out:
+	dqput(old_dquot);
+	mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_scan_active);
+
+int vfs_quota_sync(struct super_block *sb, int type)
+{
+	struct list_head *dirty;
+	struct dquot *dquot;
+	struct quota_info *dqopt = sb_dqopt(sb);
+	int cnt;
+
+	mutex_lock(&dqopt->dqonoff_mutex);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (type != -1 && cnt != type)
+			continue;
+		if (!sb_has_quota_active(sb, cnt))
+			continue;
+		spin_lock(&dq_list_lock);
+		dirty = &dqopt->info[cnt].dqi_dirty_list;
+		while (!list_empty(dirty)) {
+			dquot = list_first_entry(dirty, struct dquot, dq_dirty);
+			/* Dirty and inactive can be only bad dquot... */
+			if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+				clear_dquot_dirty(dquot);
+				continue;
+			}
+			/* Now we have active dquot from which someone is
+ 			 * holding reference so we can safely just increase
+			 * use count */
+			atomic_inc(&dquot->dq_count);
+			dqstats.lookups++;
+			spin_unlock(&dq_list_lock);
+			sb->dq_op->write_dquot(dquot);
+			dqput(dquot);
+			spin_lock(&dq_list_lock);
+		}
+		spin_unlock(&dq_list_lock);
+	}
+
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
+		    && info_dirty(&dqopt->info[cnt]))
+			sb->dq_op->write_info(sb, cnt);
+	spin_lock(&dq_list_lock);
+	dqstats.syncs++;
+	spin_unlock(&dq_list_lock);
+	mutex_unlock(&dqopt->dqonoff_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL(vfs_quota_sync);
+
+/* Free unused dquots from cache */
+static void prune_dqcache(int count)
+{
+	struct list_head *head;
+	struct dquot *dquot;
+
+	head = free_dquots.prev;
+	while (head != &free_dquots && count) {
+		dquot = list_entry(head, struct dquot, dq_free);
+		remove_dquot_hash(dquot);
+		remove_free_dquot(dquot);
+		remove_inuse(dquot);
+		do_destroy_dquot(dquot);
+		count--;
+		head = free_dquots.prev;
+	}
+}
+
+/*
+ * This is called from kswapd when we think we need some
+ * more memory
+ */
+
+static int shrink_dqcache_memory(int nr, gfp_t gfp_mask)
+{
+	if (nr) {
+		spin_lock(&dq_list_lock);
+		prune_dqcache(nr);
+		spin_unlock(&dq_list_lock);
+	}
+	return (dqstats.free_dquots / 100) * sysctl_vfs_cache_pressure;
+}
+
+static struct shrinker dqcache_shrinker = {
+	.shrink = shrink_dqcache_memory,
+	.seeks = DEFAULT_SEEKS,
+};
+
+/*
+ * Put reference to dquot
+ * NOTE: If you change this function please check whether dqput_blocks() works right...
+ */
+void dqput(struct dquot *dquot)
+{
+	int ret;
+
+	if (!dquot)
+		return;
+#ifdef __DQUOT_PARANOIA
+	if (!atomic_read(&dquot->dq_count)) {
+		printk("VFS: dqput: trying to free free dquot\n");
+		printk("VFS: device %s, dquot of %s %d\n",
+			dquot->dq_sb->s_id,
+			quotatypes[dquot->dq_type],
+			dquot->dq_id);
+		BUG();
+	}
+#endif
+	
+	spin_lock(&dq_list_lock);
+	dqstats.drops++;
+	spin_unlock(&dq_list_lock);
+we_slept:
+	spin_lock(&dq_list_lock);
+	if (atomic_read(&dquot->dq_count) > 1) {
+		/* We have more than one user... nothing to do */
+		atomic_dec(&dquot->dq_count);
+		/* Releasing dquot during quotaoff phase? */
+		if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_type) &&
+		    atomic_read(&dquot->dq_count) == 1)
+			wake_up(&dquot->dq_wait_unused);
+		spin_unlock(&dq_list_lock);
+		return;
+	}
+	/* Need to release dquot? */
+	if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && dquot_dirty(dquot)) {
+		spin_unlock(&dq_list_lock);
+		/* Commit dquot before releasing */
+		ret = dquot->dq_sb->dq_op->write_dquot(dquot);
+		if (ret < 0) {
+			printk(KERN_ERR "VFS: cannot write quota structure on "
+				"device %s (error %d). Quota may get out of "
+				"sync!\n", dquot->dq_sb->s_id, ret);
+			/*
+			 * We clear dirty bit anyway, so that we avoid
+			 * infinite loop here
+			 */
+			spin_lock(&dq_list_lock);
+			clear_dquot_dirty(dquot);
+			spin_unlock(&dq_list_lock);
+		}
+		goto we_slept;
+	}
+	/* Clear flag in case dquot was inactive (something bad happened) */
+	clear_dquot_dirty(dquot);
+	if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
+		spin_unlock(&dq_list_lock);
+		dquot->dq_sb->dq_op->release_dquot(dquot);
+		goto we_slept;
+	}
+	atomic_dec(&dquot->dq_count);
+#ifdef __DQUOT_PARANOIA
+	/* sanity check */
+	BUG_ON(!list_empty(&dquot->dq_free));
+#endif
+	put_dquot_last(dquot);
+	spin_unlock(&dq_list_lock);
+}
+EXPORT_SYMBOL(dqput);
+
+struct dquot *dquot_alloc(struct super_block *sb, int type)
+{
+	return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
+}
+EXPORT_SYMBOL(dquot_alloc);
+
+static struct dquot *get_empty_dquot(struct super_block *sb, int type)
+{
+	struct dquot *dquot;
+
+	dquot = sb->dq_op->alloc_dquot(sb, type);
+	if(!dquot)
+		return NODQUOT;
+
+	mutex_init(&dquot->dq_lock);
+	INIT_LIST_HEAD(&dquot->dq_free);
+	INIT_LIST_HEAD(&dquot->dq_inuse);
+	INIT_HLIST_NODE(&dquot->dq_hash);
+	INIT_LIST_HEAD(&dquot->dq_dirty);
+	init_waitqueue_head(&dquot->dq_wait_unused);
+	dquot->dq_sb = sb;
+	dquot->dq_type = type;
+	atomic_set(&dquot->dq_count, 1);
+
+	return dquot;
+}
+
+/*
+ * Get reference to dquot
+ *
+ * Locking is slightly tricky here. We are guarded from parallel quotaoff()
+ * destroying our dquot by:
+ *   a) checking for quota flags under dq_list_lock and
+ *   b) getting a reference to dquot before we release dq_list_lock
+ */
+struct dquot *dqget(struct super_block *sb, unsigned int id, int type)
+{
+	unsigned int hashent = hashfn(sb, id, type);
+	struct dquot *dquot = NODQUOT, *empty = NODQUOT;
+
+        if (!sb_has_quota_active(sb, type))
+		return NODQUOT;
+we_slept:
+	spin_lock(&dq_list_lock);
+	spin_lock(&dq_state_lock);
+	if (!sb_has_quota_active(sb, type)) {
+		spin_unlock(&dq_state_lock);
+		spin_unlock(&dq_list_lock);
+		goto out;
+	}
+	spin_unlock(&dq_state_lock);
+
+	if ((dquot = find_dquot(hashent, sb, id, type)) == NODQUOT) {
+		if (empty == NODQUOT) {
+			spin_unlock(&dq_list_lock);
+			if ((empty = get_empty_dquot(sb, type)) == NODQUOT)
+				schedule();	/* Try to wait for a moment... */
+			goto we_slept;
+		}
+		dquot = empty;
+		empty = NODQUOT;
+		dquot->dq_id = id;
+		/* all dquots go on the inuse_list */
+		put_inuse(dquot);
+		/* hash it first so it can be found */
+		insert_dquot_hash(dquot);
+		dqstats.lookups++;
+		spin_unlock(&dq_list_lock);
+	} else {
+		if (!atomic_read(&dquot->dq_count))
+			remove_free_dquot(dquot);
+		atomic_inc(&dquot->dq_count);
+		dqstats.cache_hits++;
+		dqstats.lookups++;
+		spin_unlock(&dq_list_lock);
+	}
+	/* Wait for dq_lock - after this we know that either dquot_release() is already
+	 * finished or it will be canceled due to dq_count > 1 test */
+	wait_on_dquot(dquot);
+	/* Read the dquot and instantiate it (everything done only if needed) */
+	if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && sb->dq_op->acquire_dquot(dquot) < 0) {
+		dqput(dquot);
+		dquot = NODQUOT;
+		goto out;
+	}
+#ifdef __DQUOT_PARANOIA
+	BUG_ON(!dquot->dq_sb);	/* Has somebody invalidated entry under us? */
+#endif
+out:
+	if (empty)
+		do_destroy_dquot(empty);
+
+	return dquot;
+}
+EXPORT_SYMBOL(dqget);
+
+static int dqinit_needed(struct inode *inode, int type)
+{
+	int cnt;
+
+	if (IS_NOQUOTA(inode))
+		return 0;
+	if (type != -1)
+		return inode->i_dquot[type] == NODQUOT;
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (inode->i_dquot[cnt] == NODQUOT)
+			return 1;
+	return 0;
+}
+
+/* This routine is guarded by dqonoff_mutex mutex */
+static void add_dquot_ref(struct super_block *sb, int type)
+{
+	struct inode *inode, *old_inode = NULL;
+
+	spin_lock(&inode_lock);
+	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
+		if (!atomic_read(&inode->i_writecount))
+			continue;
+		if (!dqinit_needed(inode, type))
+			continue;
+		if (inode->i_state & (I_FREEING|I_WILL_FREE))
+			continue;
+
+		__iget(inode);
+		spin_unlock(&inode_lock);
+
+		iput(old_inode);
+		sb->dq_op->initialize(inode, type);
+		/* We hold a reference to 'inode' so it couldn't have been
+		 * removed from s_inodes list while we dropped the inode_lock.
+		 * We cannot iput the inode now as we can be holding the last
+		 * reference and we cannot iput it under inode_lock. So we
+		 * keep the reference and iput it later. */
+		old_inode = inode;
+		spin_lock(&inode_lock);
+	}
+	spin_unlock(&inode_lock);
+	iput(old_inode);
+}
+
+/* Return 0 if dqput() won't block (note that 1 doesn't necessarily mean blocking) */
+static inline int dqput_blocks(struct dquot *dquot)
+{
+	if (atomic_read(&dquot->dq_count) <= 1)
+		return 1;
+	return 0;
+}
+
+/* Remove references to dquots from inode - add dquot to list for freeing if needed */
+/* We can't race with anybody because we hold dqptr_sem for writing... */
+static int remove_inode_dquot_ref(struct inode *inode, int type,
+				  struct list_head *tofree_head)
+{
+	struct dquot *dquot = inode->i_dquot[type];
+
+	inode->i_dquot[type] = NODQUOT;
+	if (dquot != NODQUOT) {
+		if (dqput_blocks(dquot)) {
+#ifdef __DQUOT_PARANOIA
+			if (atomic_read(&dquot->dq_count) != 1)
+				printk(KERN_WARNING "VFS: Adding dquot with dq_count %d to dispose list.\n", atomic_read(&dquot->dq_count));
+#endif
+			spin_lock(&dq_list_lock);
+			list_add(&dquot->dq_free, tofree_head);	/* As dquot must have currently users it can't be on the free list... */
+			spin_unlock(&dq_list_lock);
+			return 1;
+		}
+		else
+			dqput(dquot);   /* We have guaranteed we won't block */
+	}
+	return 0;
+}
+
+/* Free list of dquots - called from inode.c */
+/* dquots are removed from inodes, no new references can be got so we are the only ones holding reference */
+static void put_dquot_list(struct list_head *tofree_head)
+{
+	struct list_head *act_head;
+	struct dquot *dquot;
+
+	act_head = tofree_head->next;
+	/* So now we have dquots on the list... Just free them */
+	while (act_head != tofree_head) {
+		dquot = list_entry(act_head, struct dquot, dq_free);
+		act_head = act_head->next;
+		list_del_init(&dquot->dq_free);	/* Remove dquot from the list so we won't have problems... */
+		dqput(dquot);
+	}
+}
+
+static void remove_dquot_ref(struct super_block *sb, int type,
+		struct list_head *tofree_head)
+{
+	struct inode *inode;
+
+	spin_lock(&inode_lock);
+	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
+		if (!IS_NOQUOTA(inode))
+			remove_inode_dquot_ref(inode, type, tofree_head);
+	}
+	spin_unlock(&inode_lock);
+}
+
+/* Gather all references from inodes and drop them */
+static void drop_dquot_ref(struct super_block *sb, int type)
+{
+	LIST_HEAD(tofree_head);
+
+	if (sb->dq_op) {
+		down_write(&sb_dqopt(sb)->dqptr_sem);
+		remove_dquot_ref(sb, type, &tofree_head);
+		up_write(&sb_dqopt(sb)->dqptr_sem);
+		put_dquot_list(&tofree_head);
+	}
+}
+
+static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
+{
+	dquot->dq_dqb.dqb_curinodes += number;
+}
+
+static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
+{
+	dquot->dq_dqb.dqb_curspace += number;
+}
+
+static inline void dquot_resv_space(struct dquot *dquot, qsize_t number)
+{
+	dquot->dq_dqb.dqb_rsvspace += number;
+}
+
+/*
+ * Claim reserved quota space
+ */
+static void dquot_claim_reserved_space(struct dquot *dquot,
+						qsize_t number)
+{
+	WARN_ON(dquot->dq_dqb.dqb_rsvspace < number);
+	dquot->dq_dqb.dqb_curspace += number;
+	dquot->dq_dqb.dqb_rsvspace -= number;
+}
+
+static inline
+void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
+{
+	dquot->dq_dqb.dqb_rsvspace -= number;
+}
+
+static inline void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
+{
+	if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
+	    dquot->dq_dqb.dqb_curinodes >= number)
+		dquot->dq_dqb.dqb_curinodes -= number;
+	else
+		dquot->dq_dqb.dqb_curinodes = 0;
+	if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
+		dquot->dq_dqb.dqb_itime = (time_t) 0;
+	clear_bit(DQ_INODES_B, &dquot->dq_flags);
+}
+
+static inline void dquot_decr_space(struct dquot *dquot, qsize_t number)
+{
+	if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
+	    dquot->dq_dqb.dqb_curspace >= number)
+		dquot->dq_dqb.dqb_curspace -= number;
+	else
+		dquot->dq_dqb.dqb_curspace = 0;
+	if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
+		dquot->dq_dqb.dqb_btime = (time_t) 0;
+	clear_bit(DQ_BLKS_B, &dquot->dq_flags);
+}
+
+static int warning_issued(struct dquot *dquot, const int warntype)
+{
+	int flag = (warntype == QUOTA_NL_BHARDWARN ||
+		warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
+		((warntype == QUOTA_NL_IHARDWARN ||
+		warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
+
+	if (!flag)
+		return 0;
+	return test_and_set_bit(flag, &dquot->dq_flags);
+}
+
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+static int flag_print_warnings = 1;
+
+static inline int need_print_warning(struct dquot *dquot)
+{
+	if (!flag_print_warnings)
+		return 0;
+
+	switch (dquot->dq_type) {
+		case USRQUOTA:
+			return current_fsuid() == dquot->dq_id;
+		case GRPQUOTA:
+			return in_group_p(dquot->dq_id);
+	}
+	return 0;
+}
+
+/* Print warning to user which exceeded quota */
+static void print_warning(struct dquot *dquot, const int warntype)
+{
+	char *msg = NULL;
+	struct tty_struct *tty;
+
+	if (warntype == QUOTA_NL_IHARDBELOW ||
+	    warntype == QUOTA_NL_ISOFTBELOW ||
+	    warntype == QUOTA_NL_BHARDBELOW ||
+	    warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(dquot))
+		return;
+
+	tty = get_current_tty();
+	if (!tty)
+		return;
+	tty_write_message(tty, dquot->dq_sb->s_id);
+	if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
+		tty_write_message(tty, ": warning, ");
+	else
+		tty_write_message(tty, ": write failed, ");
+	tty_write_message(tty, quotatypes[dquot->dq_type]);
+	switch (warntype) {
+		case QUOTA_NL_IHARDWARN:
+			msg = " file limit reached.\r\n";
+			break;
+		case QUOTA_NL_ISOFTLONGWARN:
+			msg = " file quota exceeded too long.\r\n";
+			break;
+		case QUOTA_NL_ISOFTWARN:
+			msg = " file quota exceeded.\r\n";
+			break;
+		case QUOTA_NL_BHARDWARN:
+			msg = " block limit reached.\r\n";
+			break;
+		case QUOTA_NL_BSOFTLONGWARN:
+			msg = " block quota exceeded too long.\r\n";
+			break;
+		case QUOTA_NL_BSOFTWARN:
+			msg = " block quota exceeded.\r\n";
+			break;
+	}
+	tty_write_message(tty, msg);
+	tty_kref_put(tty);
+}
+#endif
+
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+
+/* Netlink family structure for quota */
+static struct genl_family quota_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = 0,
+	.name = "VFS_DQUOT",
+	.version = 1,
+	.maxattr = QUOTA_NL_A_MAX,
+};
+
+/* Send warning to userspace about user which exceeded quota */
+static void send_warning(const struct dquot *dquot, const char warntype)
+{
+	static atomic_t seq;
+	struct sk_buff *skb;
+	void *msg_head;
+	int ret;
+	int msg_size = 4 * nla_total_size(sizeof(u32)) +
+		       2 * nla_total_size(sizeof(u64));
+
+	/* We have to allocate using GFP_NOFS as we are called from a
+	 * filesystem performing write and thus further recursion into
+	 * the fs to free some data could cause deadlocks. */
+	skb = genlmsg_new(msg_size, GFP_NOFS);
+	if (!skb) {
+		printk(KERN_ERR
+		  "VFS: Not enough memory to send quota warning.\n");
+		return;
+	}
+	msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
+			&quota_genl_family, 0, QUOTA_NL_C_WARNING);
+	if (!msg_head) {
+		printk(KERN_ERR
+		  "VFS: Cannot store netlink header in quota warning.\n");
+		goto err_out;
+	}
+	ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, dquot->dq_type);
+	if (ret)
+		goto attr_err_out;
+	ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, dquot->dq_id);
+	if (ret)
+		goto attr_err_out;
+	ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
+	if (ret)
+		goto attr_err_out;
+	ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR,
+		MAJOR(dquot->dq_sb->s_dev));
+	if (ret)
+		goto attr_err_out;
+	ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR,
+		MINOR(dquot->dq_sb->s_dev));
+	if (ret)
+		goto attr_err_out;
+	ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
+	if (ret)
+		goto attr_err_out;
+	genlmsg_end(skb, msg_head);
+
+	ret = genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
+	if (ret < 0 && ret != -ESRCH)
+		printk(KERN_ERR
+			"VFS: Failed to send notification message: %d\n", ret);
+	return;
+attr_err_out:
+	printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
+err_out:
+	kfree_skb(skb);
+}
+#endif
+/*
+ * Write warnings to the console and send warning messages over netlink.
+ *
+ * Note that this function can sleep.
+ */
+static inline void flush_warnings(struct dquot * const *dquots, char *warntype)
+{
+	int i;
+
+	for (i = 0; i < MAXQUOTAS; i++)
+		if (dquots[i] != NODQUOT && warntype[i] != QUOTA_NL_NOWARN &&
+		    !warning_issued(dquots[i], warntype[i])) {
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+			print_warning(dquots[i], warntype[i]);
+#endif
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+			send_warning(dquots[i], warntype[i]);
+#endif
+		}
+}
+
+static inline char ignore_hardlimit(struct dquot *dquot)
+{
+	struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
+
+	return capable(CAP_SYS_RESOURCE) &&
+	    (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD || !(info->dqi_flags & V1_DQF_RSQUASH));
+}
+
+/* needs dq_data_lock */
+static int check_idq(struct dquot *dquot, qsize_t inodes, char *warntype)
+{
+	*warntype = QUOTA_NL_NOWARN;
+	if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) ||
+	    test_bit(DQ_FAKE_B, &dquot->dq_flags))
+		return QUOTA_OK;
+
+	if (dquot->dq_dqb.dqb_ihardlimit &&
+	   (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_ihardlimit &&
+            !ignore_hardlimit(dquot)) {
+		*warntype = QUOTA_NL_IHARDWARN;
+		return NO_QUOTA;
+	}
+
+	if (dquot->dq_dqb.dqb_isoftlimit &&
+	   (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
+	    dquot->dq_dqb.dqb_itime && get_seconds() >= dquot->dq_dqb.dqb_itime &&
+            !ignore_hardlimit(dquot)) {
+		*warntype = QUOTA_NL_ISOFTLONGWARN;
+		return NO_QUOTA;
+	}
+
+	if (dquot->dq_dqb.dqb_isoftlimit &&
+	   (dquot->dq_dqb.dqb_curinodes + inodes) > dquot->dq_dqb.dqb_isoftlimit &&
+	    dquot->dq_dqb.dqb_itime == 0) {
+		*warntype = QUOTA_NL_ISOFTWARN;
+		dquot->dq_dqb.dqb_itime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_igrace;
+	}
+
+	return QUOTA_OK;
+}
+
+/* needs dq_data_lock */
+static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc, char *warntype)
+{
+	qsize_t tspace;
+
+	*warntype = QUOTA_NL_NOWARN;
+	if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type) ||
+	    test_bit(DQ_FAKE_B, &dquot->dq_flags))
+		return QUOTA_OK;
+
+	tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
+		+ space;
+
+	if (dquot->dq_dqb.dqb_bhardlimit &&
+	    tspace > dquot->dq_dqb.dqb_bhardlimit &&
+            !ignore_hardlimit(dquot)) {
+		if (!prealloc)
+			*warntype = QUOTA_NL_BHARDWARN;
+		return NO_QUOTA;
+	}
+
+	if (dquot->dq_dqb.dqb_bsoftlimit &&
+	    tspace > dquot->dq_dqb.dqb_bsoftlimit &&
+	    dquot->dq_dqb.dqb_btime && get_seconds() >= dquot->dq_dqb.dqb_btime &&
+            !ignore_hardlimit(dquot)) {
+		if (!prealloc)
+			*warntype = QUOTA_NL_BSOFTLONGWARN;
+		return NO_QUOTA;
+	}
+
+	if (dquot->dq_dqb.dqb_bsoftlimit &&
+	    tspace > dquot->dq_dqb.dqb_bsoftlimit &&
+	    dquot->dq_dqb.dqb_btime == 0) {
+		if (!prealloc) {
+			*warntype = QUOTA_NL_BSOFTWARN;
+			dquot->dq_dqb.dqb_btime = get_seconds() + sb_dqopt(dquot->dq_sb)->info[dquot->dq_type].dqi_bgrace;
+		}
+		else
+			/*
+			 * We don't allow preallocation to exceed softlimit so exceeding will
+			 * be always printed
+			 */
+			return NO_QUOTA;
+	}
+
+	return QUOTA_OK;
+}
+
+static int info_idq_free(struct dquot *dquot, qsize_t inodes)
+{
+	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
+	    dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
+	    !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_type))
+		return QUOTA_NL_NOWARN;
+
+	if (dquot->dq_dqb.dqb_curinodes - inodes <= dquot->dq_dqb.dqb_isoftlimit)
+		return QUOTA_NL_ISOFTBELOW;
+	if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
+	    dquot->dq_dqb.dqb_curinodes - inodes < dquot->dq_dqb.dqb_ihardlimit)
+		return QUOTA_NL_IHARDBELOW;
+	return QUOTA_NL_NOWARN;
+}
+
+static int info_bdq_free(struct dquot *dquot, qsize_t space)
+{
+	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
+	    dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
+		return QUOTA_NL_NOWARN;
+
+	if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
+		return QUOTA_NL_BSOFTBELOW;
+	if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
+	    dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
+		return QUOTA_NL_BHARDBELOW;
+	return QUOTA_NL_NOWARN;
+}
+/*
+ *	Initialize quota pointers in inode
+ *	We do things in a bit complicated way but by that we avoid calling
+ *	dqget() and thus filesystem callbacks under dqptr_sem.
+ */
+int dquot_initialize(struct inode *inode, int type)
+{
+	unsigned int id = 0;
+	int cnt, ret = 0;
+	struct dquot *got[MAXQUOTAS] = { NODQUOT, NODQUOT };
+	struct super_block *sb = inode->i_sb;
+
+	/* First test before acquiring mutex - solves deadlocks when we
+         * re-enter the quota code and are already holding the mutex */
+	if (IS_NOQUOTA(inode))
+		return 0;
+
+	/* First get references to structures we might need. */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (type != -1 && cnt != type)
+			continue;
+		switch (cnt) {
+		case USRQUOTA:
+			id = inode->i_uid;
+			break;
+		case GRPQUOTA:
+			id = inode->i_gid;
+			break;
+		}
+		got[cnt] = dqget(sb, id, cnt);
+	}
+
+	down_write(&sb_dqopt(sb)->dqptr_sem);
+	/* Having dqptr_sem we know NOQUOTA flags can't be altered... */
+	if (IS_NOQUOTA(inode))
+		goto out_err;
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (type != -1 && cnt != type)
+			continue;
+		/* Avoid races with quotaoff() */
+		if (!sb_has_quota_active(sb, cnt))
+			continue;
+		if (inode->i_dquot[cnt] == NODQUOT) {
+			inode->i_dquot[cnt] = got[cnt];
+			got[cnt] = NODQUOT;
+		}
+	}
+out_err:
+	up_write(&sb_dqopt(sb)->dqptr_sem);
+	/* Drop unused references */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		dqput(got[cnt]);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_initialize);
+
+/*
+ * 	Release all quotas referenced by inode
+ */
+int dquot_drop(struct inode *inode)
+{
+	int cnt;
+	struct dquot *put[MAXQUOTAS];
+
+	down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		put[cnt] = inode->i_dquot[cnt];
+		inode->i_dquot[cnt] = NODQUOT;
+	}
+	up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		dqput(put[cnt]);
+	return 0;
+}
+EXPORT_SYMBOL(dquot_drop);
+
+/* Wrapper to remove references to quota structures from inode */
+void vfs_dq_drop(struct inode *inode)
+{
+	/* Here we can get arbitrary inode from clear_inode() so we have
+	 * to be careful. OTOH we don't need locking as quota operations
+	 * are allowed to change only at mount time */
+	if (!IS_NOQUOTA(inode) && inode->i_sb && inode->i_sb->dq_op
+	    && inode->i_sb->dq_op->drop) {
+		int cnt;
+		/* Test before calling to rule out calls from proc and such
+                 * where we are not allowed to block. Note that this is
+		 * actually reliable test even without the lock - the caller
+		 * must assure that nobody can come after the DQUOT_DROP and
+		 * add quota pointers back anyway */
+		for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+			if (inode->i_dquot[cnt] != NODQUOT)
+				break;
+		if (cnt < MAXQUOTAS)
+			inode->i_sb->dq_op->drop(inode);
+	}
+}
+EXPORT_SYMBOL(vfs_dq_drop);
+
+/*
+ * Following four functions update i_blocks+i_bytes fields and
+ * quota information (together with appropriate checks)
+ * NOTE: We absolutely rely on the fact that caller dirties
+ * the inode (usually macros in quotaops.h care about this) and
+ * holds a handle for the current transaction so that dquot write and
+ * inode write go into the same transaction.
+ */
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int __dquot_alloc_space(struct inode *inode, qsize_t number,
+			int warn, int reserve)
+{
+	int cnt, ret = QUOTA_OK;
+	char warntype[MAXQUOTAS];
+
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		warntype[cnt] = QUOTA_NL_NOWARN;
+
+	spin_lock(&dq_data_lock);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		if (check_bdq(inode->i_dquot[cnt], number, warn, warntype+cnt)
+		    == NO_QUOTA) {
+			ret = NO_QUOTA;
+			goto out_unlock;
+		}
+	}
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		if (reserve)
+			dquot_resv_space(inode->i_dquot[cnt], number);
+		else
+			dquot_incr_space(inode->i_dquot[cnt], number);
+	}
+	if (!reserve)
+		inode_add_bytes(inode, number);
+out_unlock:
+	spin_unlock(&dq_data_lock);
+	flush_warnings(inode->i_dquot, warntype);
+	return ret;
+}
+
+int dquot_alloc_space(struct inode *inode, qsize_t number, int warn)
+{
+	int cnt, ret = QUOTA_OK;
+
+	/*
+	 * First test before acquiring mutex - solves deadlocks when we
+	 * re-enter the quota code and are already holding the mutex
+	 */
+	if (IS_NOQUOTA(inode)) {
+		inode_add_bytes(inode, number);
+		goto out;
+	}
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	if (IS_NOQUOTA(inode)) {
+		inode_add_bytes(inode, number);
+		goto out_unlock;
+	}
+
+	ret = __dquot_alloc_space(inode, number, warn, 0);
+	if (ret == NO_QUOTA)
+		goto out_unlock;
+
+	/* Dirtify all the dquots - this can block when journalling */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (inode->i_dquot[cnt])
+			mark_dquot_dirty(inode->i_dquot[cnt]);
+out_unlock:
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+	return ret;
+}
+EXPORT_SYMBOL(dquot_alloc_space);
+
+int dquot_reserve_space(struct inode *inode, qsize_t number, int warn)
+{
+	int ret = QUOTA_OK;
+
+	if (IS_NOQUOTA(inode))
+		goto out;
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	if (IS_NOQUOTA(inode))
+		goto out_unlock;
+
+	ret = __dquot_alloc_space(inode, number, warn, 1);
+out_unlock:
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+	return ret;
+}
+EXPORT_SYMBOL(dquot_reserve_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_alloc_inode(const struct inode *inode, qsize_t number)
+{
+	int cnt, ret = NO_QUOTA;
+	char warntype[MAXQUOTAS];
+
+	/* First test before acquiring mutex - solves deadlocks when we
+         * re-enter the quota code and are already holding the mutex */
+	if (IS_NOQUOTA(inode))
+		return QUOTA_OK;
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		warntype[cnt] = QUOTA_NL_NOWARN;
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	if (IS_NOQUOTA(inode)) {
+		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+		return QUOTA_OK;
+	}
+	spin_lock(&dq_data_lock);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		if (check_idq(inode->i_dquot[cnt], number, warntype+cnt) == NO_QUOTA)
+			goto warn_put_all;
+	}
+
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		dquot_incr_inodes(inode->i_dquot[cnt], number);
+	}
+	ret = QUOTA_OK;
+warn_put_all:
+	spin_unlock(&dq_data_lock);
+	if (ret == QUOTA_OK)
+		/* Dirtify all the dquots - this can block when journalling */
+		for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+			if (inode->i_dquot[cnt])
+				mark_dquot_dirty(inode->i_dquot[cnt]);
+	flush_warnings(inode->i_dquot, warntype);
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_alloc_inode);
+
+int dquot_claim_space(struct inode *inode, qsize_t number)
+{
+	int cnt;
+	int ret = QUOTA_OK;
+
+	if (IS_NOQUOTA(inode)) {
+		inode_add_bytes(inode, number);
+		goto out;
+	}
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	if (IS_NOQUOTA(inode))	{
+		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+		inode_add_bytes(inode, number);
+		goto out;
+	}
+
+	spin_lock(&dq_data_lock);
+	/* Claim reserved quotas to allocated quotas */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] != NODQUOT)
+			dquot_claim_reserved_space(inode->i_dquot[cnt],
+							number);
+	}
+	/* Update inode bytes */
+	inode_add_bytes(inode, number);
+	spin_unlock(&dq_data_lock);
+	/* Dirtify all the dquots - this can block when journalling */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (inode->i_dquot[cnt])
+			mark_dquot_dirty(inode->i_dquot[cnt]);
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+	return ret;
+}
+EXPORT_SYMBOL(dquot_claim_space);
+
+/*
+ * Release reserved quota space
+ */
+void dquot_release_reserved_space(struct inode *inode, qsize_t number)
+{
+	int cnt;
+
+	if (IS_NOQUOTA(inode))
+		goto out;
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	if (IS_NOQUOTA(inode))
+		goto out_unlock;
+
+	spin_lock(&dq_data_lock);
+	/* Release reserved dquots */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] != NODQUOT)
+			dquot_free_reserved_space(inode->i_dquot[cnt], number);
+	}
+	spin_unlock(&dq_data_lock);
+
+out_unlock:
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+out:
+	return;
+}
+EXPORT_SYMBOL(dquot_release_reserved_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_free_space(struct inode *inode, qsize_t number)
+{
+	unsigned int cnt;
+	char warntype[MAXQUOTAS];
+
+	/* First test before acquiring mutex - solves deadlocks when we
+         * re-enter the quota code and are already holding the mutex */
+	if (IS_NOQUOTA(inode)) {
+out_sub:
+		inode_sub_bytes(inode, number);
+		return QUOTA_OK;
+	}
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	/* Now recheck reliably when holding dqptr_sem */
+	if (IS_NOQUOTA(inode)) {
+		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+		goto out_sub;
+	}
+	spin_lock(&dq_data_lock);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		warntype[cnt] = info_bdq_free(inode->i_dquot[cnt], number);
+		dquot_decr_space(inode->i_dquot[cnt], number);
+	}
+	inode_sub_bytes(inode, number);
+	spin_unlock(&dq_data_lock);
+	/* Dirtify all the dquots - this can block when journalling */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (inode->i_dquot[cnt])
+			mark_dquot_dirty(inode->i_dquot[cnt]);
+	flush_warnings(inode->i_dquot, warntype);
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	return QUOTA_OK;
+}
+EXPORT_SYMBOL(dquot_free_space);
+
+/*
+ * This operation can block, but only after everything is updated
+ */
+int dquot_free_inode(const struct inode *inode, qsize_t number)
+{
+	unsigned int cnt;
+	char warntype[MAXQUOTAS];
+
+	/* First test before acquiring mutex - solves deadlocks when we
+         * re-enter the quota code and are already holding the mutex */
+	if (IS_NOQUOTA(inode))
+		return QUOTA_OK;
+
+	down_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	/* Now recheck reliably when holding dqptr_sem */
+	if (IS_NOQUOTA(inode)) {
+		up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+		return QUOTA_OK;
+	}
+	spin_lock(&dq_data_lock);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (inode->i_dquot[cnt] == NODQUOT)
+			continue;
+		warntype[cnt] = info_idq_free(inode->i_dquot[cnt], number);
+		dquot_decr_inodes(inode->i_dquot[cnt], number);
+	}
+	spin_unlock(&dq_data_lock);
+	/* Dirtify all the dquots - this can block when journalling */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (inode->i_dquot[cnt])
+			mark_dquot_dirty(inode->i_dquot[cnt]);
+	flush_warnings(inode->i_dquot, warntype);
+	up_read(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	return QUOTA_OK;
+}
+EXPORT_SYMBOL(dquot_free_inode);
+
+/*
+ * call back function, get reserved quota space from underlying fs
+ */
+qsize_t dquot_get_reserved_space(struct inode *inode)
+{
+	qsize_t reserved_space = 0;
+
+	if (sb_any_quota_active(inode->i_sb) &&
+	    inode->i_sb->dq_op->get_reserved_space)
+		reserved_space = inode->i_sb->dq_op->get_reserved_space(inode);
+	return reserved_space;
+}
+
+/*
+ * Transfer the number of inode and blocks from one diskquota to an other.
+ *
+ * This operation can block, but only after everything is updated
+ * A transaction must be started when entering this function.
+ */
+int dquot_transfer(struct inode *inode, struct iattr *iattr)
+{
+	qsize_t space, cur_space;
+	qsize_t rsv_space = 0;
+	struct dquot *transfer_from[MAXQUOTAS];
+	struct dquot *transfer_to[MAXQUOTAS];
+	int cnt, ret = QUOTA_OK;
+	int chuid = iattr->ia_valid & ATTR_UID && inode->i_uid != iattr->ia_uid,
+	    chgid = iattr->ia_valid & ATTR_GID && inode->i_gid != iattr->ia_gid;
+	char warntype_to[MAXQUOTAS];
+	char warntype_from_inodes[MAXQUOTAS], warntype_from_space[MAXQUOTAS];
+
+	/* First test before acquiring mutex - solves deadlocks when we
+         * re-enter the quota code and are already holding the mutex */
+	if (IS_NOQUOTA(inode))
+		return QUOTA_OK;
+	/* Initialize the arrays */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		transfer_from[cnt] = NODQUOT;
+		transfer_to[cnt] = NODQUOT;
+		warntype_to[cnt] = QUOTA_NL_NOWARN;
+		switch (cnt) {
+			case USRQUOTA:
+				if (!chuid)
+					continue;
+				transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_uid, cnt);
+				break;
+			case GRPQUOTA:
+				if (!chgid)
+					continue;
+				transfer_to[cnt] = dqget(inode->i_sb, iattr->ia_gid, cnt);
+				break;
+		}
+	}
+
+	down_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	/* Now recheck reliably when holding dqptr_sem */
+	if (IS_NOQUOTA(inode)) {	/* File without quota accounting? */
+		up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+		goto put_all;
+	}
+	spin_lock(&dq_data_lock);
+	cur_space = inode_get_bytes(inode);
+	rsv_space = dquot_get_reserved_space(inode);
+	space = cur_space + rsv_space;
+	/* Build the transfer_from list and check the limits */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (transfer_to[cnt] == NODQUOT)
+			continue;
+		transfer_from[cnt] = inode->i_dquot[cnt];
+		if (check_idq(transfer_to[cnt], 1, warntype_to + cnt) ==
+		    NO_QUOTA || check_bdq(transfer_to[cnt], space, 0,
+		    warntype_to + cnt) == NO_QUOTA)
+			goto over_quota;
+	}
+
+	/*
+	 * Finally perform the needed transfer from transfer_from to transfer_to
+	 */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		/*
+		 * Skip changes for same uid or gid or for turned off quota-type.
+		 */
+		if (transfer_to[cnt] == NODQUOT)
+			continue;
+
+		/* Due to IO error we might not have transfer_from[] structure */
+		if (transfer_from[cnt]) {
+			warntype_from_inodes[cnt] =
+				info_idq_free(transfer_from[cnt], 1);
+			warntype_from_space[cnt] =
+				info_bdq_free(transfer_from[cnt], space);
+			dquot_decr_inodes(transfer_from[cnt], 1);
+			dquot_decr_space(transfer_from[cnt], cur_space);
+			dquot_free_reserved_space(transfer_from[cnt],
+						  rsv_space);
+		}
+
+		dquot_incr_inodes(transfer_to[cnt], 1);
+		dquot_incr_space(transfer_to[cnt], cur_space);
+		dquot_resv_space(transfer_to[cnt], rsv_space);
+
+		inode->i_dquot[cnt] = transfer_to[cnt];
+	}
+	spin_unlock(&dq_data_lock);
+	up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+
+	/* Dirtify all the dquots - this can block when journalling */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (transfer_from[cnt])
+			mark_dquot_dirty(transfer_from[cnt]);
+		if (transfer_to[cnt]) {
+			mark_dquot_dirty(transfer_to[cnt]);
+			/* The reference we got is transferred to the inode */
+			transfer_to[cnt] = NODQUOT;
+		}
+	}
+warn_put_all:
+	flush_warnings(transfer_to, warntype_to);
+	flush_warnings(transfer_from, warntype_from_inodes);
+	flush_warnings(transfer_from, warntype_from_space);
+put_all:
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		dqput(transfer_from[cnt]);
+		dqput(transfer_to[cnt]);
+	}
+	return ret;
+over_quota:
+	spin_unlock(&dq_data_lock);
+	up_write(&sb_dqopt(inode->i_sb)->dqptr_sem);
+	/* Clear dquot pointers we don't want to dqput() */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		transfer_from[cnt] = NODQUOT;
+	ret = NO_QUOTA;
+	goto warn_put_all;
+}
+EXPORT_SYMBOL(dquot_transfer);
+
+/* Wrapper for transferring ownership of an inode */
+int vfs_dq_transfer(struct inode *inode, struct iattr *iattr)
+{
+	if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
+		vfs_dq_init(inode);
+		if (inode->i_sb->dq_op->transfer(inode, iattr) == NO_QUOTA)
+			return 1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(vfs_dq_transfer);
+
+/*
+ * Write info of quota file to disk
+ */
+int dquot_commit_info(struct super_block *sb, int type)
+{
+	int ret;
+	struct quota_info *dqopt = sb_dqopt(sb);
+
+	mutex_lock(&dqopt->dqio_mutex);
+	ret = dqopt->ops[type]->write_file_info(sb, type);
+	mutex_unlock(&dqopt->dqio_mutex);
+	return ret;
+}
+EXPORT_SYMBOL(dquot_commit_info);
+
+/*
+ * Definitions of diskquota operations.
+ */
+struct dquot_operations dquot_operations = {
+	.initialize	= dquot_initialize,
+	.drop		= 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	= dquot_commit,
+	.acquire_dquot	= dquot_acquire,
+	.release_dquot	= dquot_release,
+	.mark_dirty	= dquot_mark_dquot_dirty,
+	.write_info	= dquot_commit_info,
+	.alloc_dquot	= dquot_alloc,
+	.destroy_dquot	= dquot_destroy,
+};
+
+/*
+ * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
+ */
+int vfs_quota_disable(struct super_block *sb, int type, unsigned int flags)
+{
+	int cnt, ret = 0;
+	struct quota_info *dqopt = sb_dqopt(sb);
+	struct inode *toputinode[MAXQUOTAS];
+
+	/* Cannot turn off usage accounting without turning off limits, or
+	 * suspend quotas and simultaneously turn quotas off. */
+	if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
+	    || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
+	    DQUOT_USAGE_ENABLED)))
+		return -EINVAL;
+
+	/* We need to serialize quota_off() for device */
+	mutex_lock(&dqopt->dqonoff_mutex);
+
+	/*
+	 * Skip everything if there's nothing to do. We have to do this because
+	 * sometimes we are called when fill_super() failed and calling
+	 * sync_fs() in such cases does no good.
+	 */
+	if (!sb_any_quota_loaded(sb)) {
+		mutex_unlock(&dqopt->dqonoff_mutex);
+		return 0;
+	}
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		toputinode[cnt] = NULL;
+		if (type != -1 && cnt != type)
+			continue;
+		if (!sb_has_quota_loaded(sb, cnt))
+			continue;
+
+		if (flags & DQUOT_SUSPENDED) {
+			spin_lock(&dq_state_lock);
+			dqopt->flags |=
+				dquot_state_flag(DQUOT_SUSPENDED, cnt);
+			spin_unlock(&dq_state_lock);
+		} else {
+			spin_lock(&dq_state_lock);
+			dqopt->flags &= ~dquot_state_flag(flags, cnt);
+			/* Turning off suspended quotas? */
+			if (!sb_has_quota_loaded(sb, cnt) &&
+			    sb_has_quota_suspended(sb, cnt)) {
+				dqopt->flags &=	~dquot_state_flag(
+							DQUOT_SUSPENDED, cnt);
+				spin_unlock(&dq_state_lock);
+				iput(dqopt->files[cnt]);
+				dqopt->files[cnt] = NULL;
+				continue;
+			}
+			spin_unlock(&dq_state_lock);
+		}
+
+		/* We still have to keep quota loaded? */
+		if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
+			continue;
+
+		/* Note: these are blocking operations */
+		drop_dquot_ref(sb, cnt);
+		invalidate_dquots(sb, cnt);
+		/*
+		 * Now all dquots should be invalidated, all writes done so we should be only
+		 * users of the info. No locks needed.
+		 */
+		if (info_dirty(&dqopt->info[cnt]))
+			sb->dq_op->write_info(sb, cnt);
+		if (dqopt->ops[cnt]->free_file_info)
+			dqopt->ops[cnt]->free_file_info(sb, cnt);
+		put_quota_format(dqopt->info[cnt].dqi_format);
+
+		toputinode[cnt] = dqopt->files[cnt];
+		if (!sb_has_quota_loaded(sb, cnt))
+			dqopt->files[cnt] = NULL;
+		dqopt->info[cnt].dqi_flags = 0;
+		dqopt->info[cnt].dqi_igrace = 0;
+		dqopt->info[cnt].dqi_bgrace = 0;
+		dqopt->ops[cnt] = NULL;
+	}
+	mutex_unlock(&dqopt->dqonoff_mutex);
+
+	/* Skip syncing and setting flags if quota files are hidden */
+	if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
+		goto put_inodes;
+
+	/* Sync the superblock so that buffers with quota data are written to
+	 * disk (and so userspace sees correct data afterwards). */
+	if (sb->s_op->sync_fs)
+		sb->s_op->sync_fs(sb, 1);
+	sync_blockdev(sb->s_bdev);
+	/* Now the quota files are just ordinary files and we can set the
+	 * inode flags back. Moreover we discard the pagecache so that
+	 * userspace sees the writes we did bypassing the pagecache. We
+	 * must also discard the blockdev buffers so that we see the
+	 * changes done by userspace on the next quotaon() */
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (toputinode[cnt]) {
+			mutex_lock(&dqopt->dqonoff_mutex);
+			/* If quota was reenabled in the meantime, we have
+			 * nothing to do */
+			if (!sb_has_quota_loaded(sb, cnt)) {
+				mutex_lock_nested(&toputinode[cnt]->i_mutex, I_MUTEX_QUOTA);
+				toputinode[cnt]->i_flags &= ~(S_IMMUTABLE |
+				  S_NOATIME | S_NOQUOTA);
+				truncate_inode_pages(&toputinode[cnt]->i_data, 0);
+				mutex_unlock(&toputinode[cnt]->i_mutex);
+				mark_inode_dirty(toputinode[cnt]);
+			}
+			mutex_unlock(&dqopt->dqonoff_mutex);
+		}
+	if (sb->s_bdev)
+		invalidate_bdev(sb->s_bdev);
+put_inodes:
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
+		if (toputinode[cnt]) {
+			/* On remount RO, we keep the inode pointer so that we
+			 * can reenable quota on the subsequent remount RW. We
+			 * have to check 'flags' variable and not use sb_has_
+			 * function because another quotaon / quotaoff could
+			 * change global state before we got here. We refuse
+			 * to suspend quotas when there is pending delete on
+			 * the quota file... */
+			if (!(flags & DQUOT_SUSPENDED))
+				iput(toputinode[cnt]);
+			else if (!toputinode[cnt]->i_nlink)
+				ret = -EBUSY;
+		}
+	return ret;
+}
+EXPORT_SYMBOL(vfs_quota_disable);
+
+int vfs_quota_off(struct super_block *sb, int type, int remount)
+{
+	return vfs_quota_disable(sb, type, remount ? DQUOT_SUSPENDED :
+				 (DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED));
+}
+EXPORT_SYMBOL(vfs_quota_off);
+/*
+ *	Turn quotas on on a device
+ */
+
+/*
+ * Helper function to turn quotas on when we already have the inode of
+ * quota file and no quota information is loaded.
+ */
+static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
+	unsigned int flags)
+{
+	struct quota_format_type *fmt = find_quota_format(format_id);
+	struct super_block *sb = inode->i_sb;
+	struct quota_info *dqopt = sb_dqopt(sb);
+	int error;
+	int oldflags = -1;
+
+	if (!fmt)
+		return -ESRCH;
+	if (!S_ISREG(inode->i_mode)) {
+		error = -EACCES;
+		goto out_fmt;
+	}
+	if (IS_RDONLY(inode)) {
+		error = -EROFS;
+		goto out_fmt;
+	}
+	if (!sb->s_op->quota_write || !sb->s_op->quota_read) {
+		error = -EINVAL;
+		goto out_fmt;
+	}
+	/* Usage always has to be set... */
+	if (!(flags & DQUOT_USAGE_ENABLED)) {
+		error = -EINVAL;
+		goto out_fmt;
+	}
+
+	if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
+		/* As we bypass the pagecache we must now flush the inode so
+		 * that we see all the changes from userspace... */
+		write_inode_now(inode, 1);
+		/* And now flush the block cache so that kernel sees the
+		 * changes */
+		invalidate_bdev(sb->s_bdev);
+	}
+	mutex_lock(&inode->i_mutex);
+	mutex_lock(&dqopt->dqonoff_mutex);
+	if (sb_has_quota_loaded(sb, type)) {
+		error = -EBUSY;
+		goto out_lock;
+	}
+
+	if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
+		/* We don't want quota and atime on quota files (deadlocks
+		 * possible) Also nobody should write to the file - we use
+		 * special IO operations which ignore the immutable bit. */
+		down_write(&dqopt->dqptr_sem);
+		oldflags = inode->i_flags & (S_NOATIME | S_IMMUTABLE | S_NOQUOTA);
+		inode->i_flags |= S_NOQUOTA | S_NOATIME | S_IMMUTABLE;
+		up_write(&dqopt->dqptr_sem);
+		sb->dq_op->drop(inode);
+	}
+
+	error = -EIO;
+	dqopt->files[type] = igrab(inode);
+	if (!dqopt->files[type])
+		goto out_lock;
+	error = -EINVAL;
+	if (!fmt->qf_ops->check_quota_file(sb, type))
+		goto out_file_init;
+
+	dqopt->ops[type] = fmt->qf_ops;
+	dqopt->info[type].dqi_format = fmt;
+	dqopt->info[type].dqi_fmt_id = format_id;
+	INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
+	mutex_lock(&dqopt->dqio_mutex);
+	if ((error = dqopt->ops[type]->read_file_info(sb, type)) < 0) {
+		mutex_unlock(&dqopt->dqio_mutex);
+		goto out_file_init;
+	}
+	mutex_unlock(&dqopt->dqio_mutex);
+	mutex_unlock(&inode->i_mutex);
+	spin_lock(&dq_state_lock);
+	dqopt->flags |= dquot_state_flag(flags, type);
+	spin_unlock(&dq_state_lock);
+
+	add_dquot_ref(sb, type);
+	mutex_unlock(&dqopt->dqonoff_mutex);
+
+	return 0;
+
+out_file_init:
+	dqopt->files[type] = NULL;
+	iput(inode);
+out_lock:
+	mutex_unlock(&dqopt->dqonoff_mutex);
+	if (oldflags != -1) {
+		down_write(&dqopt->dqptr_sem);
+		/* Set the flags back (in the case of accidental quotaon()
+		 * on a wrong file we don't want to mess up the flags) */
+		inode->i_flags &= ~(S_NOATIME | S_NOQUOTA | S_IMMUTABLE);
+		inode->i_flags |= oldflags;
+		up_write(&dqopt->dqptr_sem);
+	}
+	mutex_unlock(&inode->i_mutex);
+out_fmt:
+	put_quota_format(fmt);
+
+	return error; 
+}
+
+/* Reenable quotas on remount RW */
+static int vfs_quota_on_remount(struct super_block *sb, int type)
+{
+	struct quota_info *dqopt = sb_dqopt(sb);
+	struct inode *inode;
+	int ret;
+	unsigned int flags;
+
+	mutex_lock(&dqopt->dqonoff_mutex);
+	if (!sb_has_quota_suspended(sb, type)) {
+		mutex_unlock(&dqopt->dqonoff_mutex);
+		return 0;
+	}
+	inode = dqopt->files[type];
+	dqopt->files[type] = NULL;
+	spin_lock(&dq_state_lock);
+	flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
+						DQUOT_LIMITS_ENABLED, type);
+	dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, type);
+	spin_unlock(&dq_state_lock);
+	mutex_unlock(&dqopt->dqonoff_mutex);
+
+	flags = dquot_generic_flag(flags, type);
+	ret = vfs_load_quota_inode(inode, type, dqopt->info[type].dqi_fmt_id,
+				   flags);
+	iput(inode);
+
+	return ret;
+}
+
+int vfs_quota_on_path(struct super_block *sb, int type, int format_id,
+		      struct path *path)
+{
+	int error = security_quota_on(path->dentry);
+	if (error)
+		return error;
+	/* Quota file not on the same filesystem? */
+	if (path->mnt->mnt_sb != sb)
+		error = -EXDEV;
+	else
+		error = vfs_load_quota_inode(path->dentry->d_inode, type,
+					     format_id, DQUOT_USAGE_ENABLED |
+					     DQUOT_LIMITS_ENABLED);
+	return error;
+}
+EXPORT_SYMBOL(vfs_quota_on_path);
+
+int vfs_quota_on(struct super_block *sb, int type, int format_id, char *name,
+		 int remount)
+{
+	struct path path;
+	int error;
+
+	if (remount)
+		return vfs_quota_on_remount(sb, type);
+
+	error = kern_path(name, LOOKUP_FOLLOW, &path);
+	if (!error) {
+		error = vfs_quota_on_path(sb, type, format_id, &path);
+		path_put(&path);
+	}
+	return error;
+}
+EXPORT_SYMBOL(vfs_quota_on);
+
+/*
+ * More powerful function for turning on quotas allowing setting
+ * of individual quota flags
+ */
+int vfs_quota_enable(struct inode *inode, int type, int format_id,
+		unsigned int flags)
+{
+	int ret = 0;
+	struct super_block *sb = inode->i_sb;
+	struct quota_info *dqopt = sb_dqopt(sb);
+
+	/* Just unsuspend quotas? */
+	if (flags & DQUOT_SUSPENDED)
+		return vfs_quota_on_remount(sb, type);
+	if (!flags)
+		return 0;
+	/* Just updating flags needed? */
+	if (sb_has_quota_loaded(sb, type)) {
+		mutex_lock(&dqopt->dqonoff_mutex);
+		/* Now do a reliable test... */
+		if (!sb_has_quota_loaded(sb, type)) {
+			mutex_unlock(&dqopt->dqonoff_mutex);
+			goto load_quota;
+		}
+		if (flags & DQUOT_USAGE_ENABLED &&
+		    sb_has_quota_usage_enabled(sb, type)) {
+			ret = -EBUSY;
+			goto out_lock;
+		}
+		if (flags & DQUOT_LIMITS_ENABLED &&
+		    sb_has_quota_limits_enabled(sb, type)) {
+			ret = -EBUSY;
+			goto out_lock;
+		}
+		spin_lock(&dq_state_lock);
+		sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
+		spin_unlock(&dq_state_lock);
+out_lock:
+		mutex_unlock(&dqopt->dqonoff_mutex);
+		return ret;
+	}
+
+load_quota:
+	return vfs_load_quota_inode(inode, type, format_id, flags);
+}
+EXPORT_SYMBOL(vfs_quota_enable);
+
+/*
+ * This function is used when filesystem needs to initialize quotas
+ * during mount time.
+ */
+int vfs_quota_on_mount(struct super_block *sb, char *qf_name,
+		int format_id, int type)
+{
+	struct dentry *dentry;
+	int error;
+
+	dentry = lookup_one_len(qf_name, sb->s_root, strlen(qf_name));
+	if (IS_ERR(dentry))
+		return PTR_ERR(dentry);
+
+	if (!dentry->d_inode) {
+		error = -ENOENT;
+		goto out;
+	}
+
+	error = security_quota_on(dentry);
+	if (!error)
+		error = vfs_load_quota_inode(dentry->d_inode, type, format_id,
+				DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
+
+out:
+	dput(dentry);
+	return error;
+}
+EXPORT_SYMBOL(vfs_quota_on_mount);
+
+/* Wrapper to turn on quotas when remounting rw */
+int vfs_dq_quota_on_remount(struct super_block *sb)
+{
+	int cnt;
+	int ret = 0, err;
+
+	if (!sb->s_qcop || !sb->s_qcop->quota_on)
+		return -ENOSYS;
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		err = sb->s_qcop->quota_on(sb, cnt, 0, NULL, 1);
+		if (err < 0 && !ret)
+			ret = err;
+	}
+	return ret;
+}
+EXPORT_SYMBOL(vfs_dq_quota_on_remount);
+
+static inline qsize_t qbtos(qsize_t blocks)
+{
+	return blocks << QIF_DQBLKSIZE_BITS;
+}
+
+static inline qsize_t stoqb(qsize_t space)
+{
+	return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
+}
+
+/* Generic routine for getting common part of quota structure */
+static void do_get_dqblk(struct dquot *dquot, struct if_dqblk *di)
+{
+	struct mem_dqblk *dm = &dquot->dq_dqb;
+
+	spin_lock(&dq_data_lock);
+	di->dqb_bhardlimit = stoqb(dm->dqb_bhardlimit);
+	di->dqb_bsoftlimit = stoqb(dm->dqb_bsoftlimit);
+	di->dqb_curspace = dm->dqb_curspace + dm->dqb_rsvspace;
+	di->dqb_ihardlimit = dm->dqb_ihardlimit;
+	di->dqb_isoftlimit = dm->dqb_isoftlimit;
+	di->dqb_curinodes = dm->dqb_curinodes;
+	di->dqb_btime = dm->dqb_btime;
+	di->dqb_itime = dm->dqb_itime;
+	di->dqb_valid = QIF_ALL;
+	spin_unlock(&dq_data_lock);
+}
+
+int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
+{
+	struct dquot *dquot;
+
+	dquot = dqget(sb, id, type);
+	if (dquot == NODQUOT)
+		return -ESRCH;
+	do_get_dqblk(dquot, di);
+	dqput(dquot);
+
+	return 0;
+}
+EXPORT_SYMBOL(vfs_get_dqblk);
+
+/* Generic routine for setting common part of quota structure */
+static int do_set_dqblk(struct dquot *dquot, struct if_dqblk *di)
+{
+	struct mem_dqblk *dm = &dquot->dq_dqb;
+	int check_blim = 0, check_ilim = 0;
+	struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_type];
+
+	if ((di->dqb_valid & QIF_BLIMITS &&
+	     (di->dqb_bhardlimit > dqi->dqi_maxblimit ||
+	      di->dqb_bsoftlimit > dqi->dqi_maxblimit)) ||
+	    (di->dqb_valid & QIF_ILIMITS &&
+	     (di->dqb_ihardlimit > dqi->dqi_maxilimit ||
+	      di->dqb_isoftlimit > dqi->dqi_maxilimit)))
+		return -ERANGE;
+
+	spin_lock(&dq_data_lock);
+	if (di->dqb_valid & QIF_SPACE) {
+		dm->dqb_curspace = di->dqb_curspace - dm->dqb_rsvspace;
+		check_blim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
+	}
+	if (di->dqb_valid & QIF_BLIMITS) {
+		dm->dqb_bsoftlimit = qbtos(di->dqb_bsoftlimit);
+		dm->dqb_bhardlimit = qbtos(di->dqb_bhardlimit);
+		check_blim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
+	}
+	if (di->dqb_valid & QIF_INODES) {
+		dm->dqb_curinodes = di->dqb_curinodes;
+		check_ilim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
+	}
+	if (di->dqb_valid & QIF_ILIMITS) {
+		dm->dqb_isoftlimit = di->dqb_isoftlimit;
+		dm->dqb_ihardlimit = di->dqb_ihardlimit;
+		check_ilim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
+	}
+	if (di->dqb_valid & QIF_BTIME) {
+		dm->dqb_btime = di->dqb_btime;
+		check_blim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
+	}
+	if (di->dqb_valid & QIF_ITIME) {
+		dm->dqb_itime = di->dqb_itime;
+		check_ilim = 1;
+		__set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
+	}
+
+	if (check_blim) {
+		if (!dm->dqb_bsoftlimit || dm->dqb_curspace < dm->dqb_bsoftlimit) {
+			dm->dqb_btime = 0;
+			clear_bit(DQ_BLKS_B, &dquot->dq_flags);
+		}
+		else if (!(di->dqb_valid & QIF_BTIME))	/* Set grace only if user hasn't provided his own... */
+			dm->dqb_btime = get_seconds() + dqi->dqi_bgrace;
+	}
+	if (check_ilim) {
+		if (!dm->dqb_isoftlimit || dm->dqb_curinodes < dm->dqb_isoftlimit) {
+			dm->dqb_itime = 0;
+			clear_bit(DQ_INODES_B, &dquot->dq_flags);
+		}
+		else if (!(di->dqb_valid & QIF_ITIME))	/* Set grace only if user hasn't provided his own... */
+			dm->dqb_itime = get_seconds() + dqi->dqi_igrace;
+	}
+	if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit || dm->dqb_isoftlimit)
+		clear_bit(DQ_FAKE_B, &dquot->dq_flags);
+	else
+		set_bit(DQ_FAKE_B, &dquot->dq_flags);
+	spin_unlock(&dq_data_lock);
+	mark_dquot_dirty(dquot);
+
+	return 0;
+}
+
+int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di)
+{
+	struct dquot *dquot;
+	int rc;
+
+	dquot = dqget(sb, id, type);
+	if (!dquot) {
+		rc = -ESRCH;
+		goto out;
+	}
+	rc = do_set_dqblk(dquot, di);
+	dqput(dquot);
+out:
+	return rc;
+}
+EXPORT_SYMBOL(vfs_set_dqblk);
+
+/* Generic routine for getting common part of quota file information */
+int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
+{
+	struct mem_dqinfo *mi;
+  
+	mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+	if (!sb_has_quota_active(sb, type)) {
+		mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+		return -ESRCH;
+	}
+	mi = sb_dqopt(sb)->info + type;
+	spin_lock(&dq_data_lock);
+	ii->dqi_bgrace = mi->dqi_bgrace;
+	ii->dqi_igrace = mi->dqi_igrace;
+	ii->dqi_flags = mi->dqi_flags & DQF_MASK;
+	ii->dqi_valid = IIF_ALL;
+	spin_unlock(&dq_data_lock);
+	mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+	return 0;
+}
+EXPORT_SYMBOL(vfs_get_dqinfo);
+
+/* Generic routine for setting common part of quota file information */
+int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii)
+{
+	struct mem_dqinfo *mi;
+	int err = 0;
+
+	mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+	if (!sb_has_quota_active(sb, type)) {
+		err = -ESRCH;
+		goto out;
+	}
+	mi = sb_dqopt(sb)->info + type;
+	spin_lock(&dq_data_lock);
+	if (ii->dqi_valid & IIF_BGRACE)
+		mi->dqi_bgrace = ii->dqi_bgrace;
+	if (ii->dqi_valid & IIF_IGRACE)
+		mi->dqi_igrace = ii->dqi_igrace;
+	if (ii->dqi_valid & IIF_FLAGS)
+		mi->dqi_flags = (mi->dqi_flags & ~DQF_MASK) | (ii->dqi_flags & DQF_MASK);
+	spin_unlock(&dq_data_lock);
+	mark_info_dirty(sb, type);
+	/* Force write to disk */
+	sb->dq_op->write_info(sb, type);
+out:
+	mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+	return err;
+}
+EXPORT_SYMBOL(vfs_set_dqinfo);
+
+struct quotactl_ops vfs_quotactl_ops = {
+	.quota_on	= vfs_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
+};
+
+static ctl_table fs_dqstats_table[] = {
+	{
+		.ctl_name	= FS_DQ_LOOKUPS,
+		.procname	= "lookups",
+		.data		= &dqstats.lookups,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_DROPS,
+		.procname	= "drops",
+		.data		= &dqstats.drops,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_READS,
+		.procname	= "reads",
+		.data		= &dqstats.reads,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_WRITES,
+		.procname	= "writes",
+		.data		= &dqstats.writes,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_CACHE_HITS,
+		.procname	= "cache_hits",
+		.data		= &dqstats.cache_hits,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_ALLOCATED,
+		.procname	= "allocated_dquots",
+		.data		= &dqstats.allocated_dquots,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_FREE,
+		.procname	= "free_dquots",
+		.data		= &dqstats.free_dquots,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+	{
+		.ctl_name	= FS_DQ_SYNCS,
+		.procname	= "syncs",
+		.data		= &dqstats.syncs,
+		.maxlen		= sizeof(int),
+		.mode		= 0444,
+		.proc_handler	= &proc_dointvec,
+	},
+#ifdef CONFIG_PRINT_QUOTA_WARNING
+	{
+		.ctl_name	= FS_DQ_WARNINGS,
+		.procname	= "warnings",
+		.data		= &flag_print_warnings,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec,
+	},
+#endif
+	{ .ctl_name = 0 },
+};
+
+static ctl_table fs_table[] = {
+	{
+		.ctl_name	= FS_DQSTATS,
+		.procname	= "quota",
+		.mode		= 0555,
+		.child		= fs_dqstats_table,
+	},
+	{ .ctl_name = 0 },
+};
+
+static ctl_table sys_table[] = {
+	{
+		.ctl_name	= CTL_FS,
+		.procname	= "fs",
+		.mode		= 0555,
+		.child		= fs_table,
+	},
+	{ .ctl_name = 0 },
+};
+
+static int __init dquot_init(void)
+{
+	int i;
+	unsigned long nr_hash, order;
+
+	printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
+
+	register_sysctl_table(sys_table);
+
+	dquot_cachep = kmem_cache_create("dquot",
+			sizeof(struct dquot), sizeof(unsigned long) * 4,
+			(SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
+				SLAB_MEM_SPREAD|SLAB_PANIC),
+			NULL);
+
+	order = 0;
+	dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
+	if (!dquot_hash)
+		panic("Cannot create dquot hash table");
+
+	/* Find power-of-two hlist_heads which can fit into allocation */
+	nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
+	dq_hash_bits = 0;
+	do {
+		dq_hash_bits++;
+	} while (nr_hash >> dq_hash_bits);
+	dq_hash_bits--;
+
+	nr_hash = 1UL << dq_hash_bits;
+	dq_hash_mask = nr_hash - 1;
+	for (i = 0; i < nr_hash; i++)
+		INIT_HLIST_HEAD(dquot_hash + i);
+
+	printk("Dquot-cache hash table entries: %ld (order %ld, %ld bytes)\n",
+			nr_hash, order, (PAGE_SIZE << order));
+
+	register_shrinker(&dqcache_shrinker);
+
+#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
+	if (genl_register_family(&quota_genl_family) != 0)
+		printk(KERN_ERR "VFS: Failed to create quota netlink interface.\n");
+#endif
+
+	return 0;
+}
+module_init(dquot_init);
diff --git a/fs/quota/quota.c b/fs/quota/quota.c
new file mode 100644
index 00000000000..d76ada914f9
--- /dev/null
+++ b/fs/quota/quota.c
@@ -0,0 +1,513 @@
+/*
+ * Quota code necessary even when VFS quota support is not compiled
+ * into the kernel.  The interesting stuff is over in dquot.c, here
+ * we have symbols for initial quotactl(2) handling, the sysctl(2)
+ * variables, etc - things needed even when quota support disabled.
+ */
+
+#include <linux/fs.h>
+#include <linux/namei.h>
+#include <linux/slab.h>
+#include <asm/current.h>
+#include <asm/uaccess.h>
+#include <linux/compat.h>
+#include <linux/kernel.h>
+#include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/buffer_head.h>
+#include <linux/capability.h>
+#include <linux/quotaops.h>
+#include <linux/types.h>
+
+/* Check validity of generic quotactl commands */
+static int generic_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
+{
+	if (type >= MAXQUOTAS)
+		return -EINVAL;
+	if (!sb && cmd != Q_SYNC)
+		return -ENODEV;
+	/* Is operation supported? */
+	if (sb && !sb->s_qcop)
+		return -ENOSYS;
+
+	switch (cmd) {
+		case Q_GETFMT:
+			break;
+		case Q_QUOTAON:
+			if (!sb->s_qcop->quota_on)
+				return -ENOSYS;
+			break;
+		case Q_QUOTAOFF:
+			if (!sb->s_qcop->quota_off)
+				return -ENOSYS;
+			break;
+		case Q_SETINFO:
+			if (!sb->s_qcop->set_info)
+				return -ENOSYS;
+			break;
+		case Q_GETINFO:
+			if (!sb->s_qcop->get_info)
+				return -ENOSYS;
+			break;
+		case Q_SETQUOTA:
+			if (!sb->s_qcop->set_dqblk)
+				return -ENOSYS;
+			break;
+		case Q_GETQUOTA:
+			if (!sb->s_qcop->get_dqblk)
+				return -ENOSYS;
+			break;
+		case Q_SYNC:
+			if (sb && !sb->s_qcop->quota_sync)
+				return -ENOSYS;
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	/* Is quota turned on for commands which need it? */
+	switch (cmd) {
+		case Q_GETFMT:
+		case Q_GETINFO:
+		case Q_SETINFO:
+		case Q_SETQUOTA:
+		case Q_GETQUOTA:
+			/* This is just informative test so we are satisfied without a lock */
+			if (!sb_has_quota_active(sb, type))
+				return -ESRCH;
+	}
+
+	/* Check privileges */
+	if (cmd == Q_GETQUOTA) {
+		if (((type == USRQUOTA && current_euid() != id) ||
+		     (type == GRPQUOTA && !in_egroup_p(id))) &&
+		    !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+	}
+	else if (cmd != Q_GETFMT && cmd != Q_SYNC && cmd != Q_GETINFO)
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+
+	return 0;
+}
+
+/* Check validity of XFS Quota Manager commands */
+static int xqm_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
+{
+	if (type >= XQM_MAXQUOTAS)
+		return -EINVAL;
+	if (!sb)
+		return -ENODEV;
+	if (!sb->s_qcop)
+		return -ENOSYS;
+
+	switch (cmd) {
+		case Q_XQUOTAON:
+		case Q_XQUOTAOFF:
+		case Q_XQUOTARM:
+			if (!sb->s_qcop->set_xstate)
+				return -ENOSYS;
+			break;
+		case Q_XGETQSTAT:
+			if (!sb->s_qcop->get_xstate)
+				return -ENOSYS;
+			break;
+		case Q_XSETQLIM:
+			if (!sb->s_qcop->set_xquota)
+				return -ENOSYS;
+			break;
+		case Q_XGETQUOTA:
+			if (!sb->s_qcop->get_xquota)
+				return -ENOSYS;
+			break;
+		case Q_XQUOTASYNC:
+			if (!sb->s_qcop->quota_sync)
+				return -ENOSYS;
+			break;
+		default:
+			return -EINVAL;
+	}
+
+	/* Check privileges */
+	if (cmd == Q_XGETQUOTA) {
+		if (((type == XQM_USRQUOTA && current_euid() != id) ||
+		     (type == XQM_GRPQUOTA && !in_egroup_p(id))) &&
+		     !capable(CAP_SYS_ADMIN))
+			return -EPERM;
+	} else if (cmd != Q_XGETQSTAT && cmd != Q_XQUOTASYNC) {
+		if (!capable(CAP_SYS_ADMIN))
+			return -EPERM;
+	}
+
+	return 0;
+}
+
+static int check_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
+{
+	int error;
+
+	if (XQM_COMMAND(cmd))
+		error = xqm_quotactl_valid(sb, type, cmd, id);
+	else
+		error = generic_quotactl_valid(sb, type, cmd, id);
+	if (!error)
+		error = security_quotactl(cmd, type, id, sb);
+	return error;
+}
+
+static void quota_sync_sb(struct super_block *sb, int type)
+{
+	int cnt;
+
+	sb->s_qcop->quota_sync(sb, type);
+
+	if (sb_dqopt(sb)->flags & DQUOT_QUOTA_SYS_FILE)
+		return;
+	/* This is not very clever (and fast) but currently I don't know about
+	 * any other simple way of getting quota data to disk and we must get
+	 * them there for userspace to be visible... */
+	if (sb->s_op->sync_fs)
+		sb->s_op->sync_fs(sb, 1);
+	sync_blockdev(sb->s_bdev);
+
+	/*
+	 * Now when everything is written we can discard the pagecache so
+	 * that userspace sees the changes.
+	 */
+	mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
+	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+		if (type != -1 && cnt != type)
+			continue;
+		if (!sb_has_quota_active(sb, cnt))
+			continue;
+		mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, I_MUTEX_QUOTA);
+		truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0);
+		mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex);
+	}
+	mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
+}
+
+void sync_dquots(struct super_block *sb, int type)
+{
+	int cnt;
+
+	if (sb) {
+		if (sb->s_qcop->quota_sync)
+			quota_sync_sb(sb, type);
+		return;
+	}
+
+	spin_lock(&sb_lock);
+restart:
+	list_for_each_entry(sb, &super_blocks, s_list) {
+		/* This test just improves performance so it needn't be reliable... */
+		for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+			if (type != -1 && type != cnt)
+				continue;
+			if (!sb_has_quota_active(sb, cnt))
+				continue;
+			if (!info_dirty(&sb_dqopt(sb)->info[cnt]) &&
+			    list_empty(&sb_dqopt(sb)->info[cnt].dqi_dirty_list))
+				continue;
+			break;
+		}
+		if (cnt == MAXQUOTAS)
+			continue;
+		sb->s_count++;
+		spin_unlock(&sb_lock);
+		down_read(&sb->s_umount);
+		if (sb->s_root && sb->s_qcop->quota_sync)
+			quota_sync_sb(sb, type);
+		up_read(&sb->s_umount);
+		spin_lock(&sb_lock);
+		if (__put_super_and_need_restart(sb))
+			goto restart;
+	}
+	spin_unlock(&sb_lock);
+}
+
+/* Copy parameters and call proper function */
+static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, void __user *addr)
+{
+	int ret;
+
+	switch (cmd) {
+		case Q_QUOTAON: {
+			char *pathname;
+
+			if (IS_ERR(pathname = getname(addr)))
+				return PTR_ERR(pathname);
+			ret = sb->s_qcop->quota_on(sb, type, id, pathname, 0);
+			putname(pathname);
+			return ret;
+		}
+		case Q_QUOTAOFF:
+			return sb->s_qcop->quota_off(sb, type, 0);
+
+		case Q_GETFMT: {
+			__u32 fmt;
+
+			down_read(&sb_dqopt(sb)->dqptr_sem);
+			if (!sb_has_quota_active(sb, type)) {
+				up_read(&sb_dqopt(sb)->dqptr_sem);
+				return -ESRCH;
+			}
+			fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
+			up_read(&sb_dqopt(sb)->dqptr_sem);
+			if (copy_to_user(addr, &fmt, sizeof(fmt)))
+				return -EFAULT;
+			return 0;
+		}
+		case Q_GETINFO: {
+			struct if_dqinfo info;
+
+			if ((ret = sb->s_qcop->get_info(sb, type, &info)))
+				return ret;
+			if (copy_to_user(addr, &info, sizeof(info)))
+				return -EFAULT;
+			return 0;
+		}
+		case Q_SETINFO: {
+			struct if_dqinfo info;
+
+			if (copy_from_user(&info, addr, sizeof(info)))
+				return -EFAULT;
+			return sb->s_qcop->set_info(sb, type, &info);
+		}
+		case Q_GETQUOTA: {
+			struct if_dqblk idq;
+
+			if ((ret = sb->s_qcop->get_dqblk(sb, type, id, &idq)))
+				return ret;
+			if (copy_to_user(addr, &idq, sizeof(idq)))
+				return -EFAULT;
+			return 0;
+		}
+		case Q_SETQUOTA: {
+			struct if_dqblk idq;
+
+			if (copy_from_user(&idq, addr, sizeof(idq)))
+				return -EFAULT;
+			return sb->s_qcop->set_dqblk(sb, type, id, &idq);
+		}
+		case Q_SYNC:
+			sync_dquots(sb, type);
+			return 0;
+
+		case Q_XQUOTAON:
+		case Q_XQUOTAOFF:
+		case Q_XQUOTARM: {
+			__u32 flags;
+
+			if (copy_from_user(&flags, addr, sizeof(flags)))
+				return -EFAULT;
+			return sb->s_qcop->set_xstate(sb, flags, cmd);
+		}
+		case Q_XGETQSTAT: {
+			struct fs_quota_stat fqs;
+		
+			if ((ret = sb->s_qcop->get_xstate(sb, &fqs)))
+				return ret;
+			if (copy_to_user(addr, &fqs, sizeof(fqs)))
+				return -EFAULT;
+			return 0;
+		}
+		case Q_XSETQLIM: {
+			struct fs_disk_quota fdq;
+
+			if (copy_from_user(&fdq, addr, sizeof(fdq)))
+				return -EFAULT;
+		       return sb->s_qcop->set_xquota(sb, type, id, &fdq);
+		}
+		case Q_XGETQUOTA: {
+			struct fs_disk_quota fdq;
+
+			if ((ret = sb->s_qcop->get_xquota(sb, type, id, &fdq)))
+				return ret;
+			if (copy_to_user(addr, &fdq, sizeof(fdq)))
+				return -EFAULT;
+			return 0;
+		}
+		case Q_XQUOTASYNC:
+			return sb->s_qcop->quota_sync(sb, type);
+		/* We never reach here unless validity check is broken */
+		default:
+			BUG();
+	}
+	return 0;
+}
+
+/*
+ * look up a superblock on which quota ops will be performed
+ * - use the name of a block device to find the superblock thereon
+ */
+static inline struct super_block *quotactl_block(const char __user *special)
+{
+#ifdef CONFIG_BLOCK
+	struct block_device *bdev;
+	struct super_block *sb;
+	char *tmp = getname(special);
+
+	if (IS_ERR(tmp))
+		return ERR_CAST(tmp);
+	bdev = lookup_bdev(tmp);
+	putname(tmp);
+	if (IS_ERR(bdev))
+		return ERR_CAST(bdev);
+	sb = get_super(bdev);
+	bdput(bdev);
+	if (!sb)
+		return ERR_PTR(-ENODEV);
+
+	return sb;
+#else
+	return ERR_PTR(-ENODEV);
+#endif
+}
+
+/*
+ * This is the system call interface. This communicates with
+ * the user-level programs. Currently this only supports diskquota
+ * calls. Maybe we need to add the process quotas etc. in the future,
+ * but we probably should use rlimits for that.
+ */
+SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
+		qid_t, id, void __user *, addr)
+{
+	uint cmds, type;
+	struct super_block *sb = NULL;
+	int ret;
+
+	cmds = cmd >> SUBCMDSHIFT;
+	type = cmd & SUBCMDMASK;
+
+	if (cmds != Q_SYNC || special) {
+		sb = quotactl_block(special);
+		if (IS_ERR(sb))
+			return PTR_ERR(sb);
+	}
+
+	ret = check_quotactl_valid(sb, type, cmds, id);
+	if (ret >= 0)
+		ret = do_quotactl(sb, type, cmds, id, addr);
+	if (sb)
+		drop_super(sb);
+
+	return ret;
+}
+
+#if defined(CONFIG_COMPAT_FOR_U64_ALIGNMENT)
+/*
+ * This code works only for 32 bit quota tools over 64 bit OS (x86_64, ia64)
+ * and is necessary due to alignment problems.
+ */
+struct compat_if_dqblk {
+	compat_u64 dqb_bhardlimit;
+	compat_u64 dqb_bsoftlimit;
+	compat_u64 dqb_curspace;
+	compat_u64 dqb_ihardlimit;
+	compat_u64 dqb_isoftlimit;
+	compat_u64 dqb_curinodes;
+	compat_u64 dqb_btime;
+	compat_u64 dqb_itime;
+	compat_uint_t dqb_valid;
+};
+
+/* XFS structures */
+struct compat_fs_qfilestat {
+	compat_u64 dqb_bhardlimit;
+	compat_u64 qfs_nblks;
+	compat_uint_t qfs_nextents;
+};
+
+struct compat_fs_quota_stat {
+	__s8		qs_version;
+	__u16		qs_flags;
+	__s8		qs_pad;
+	struct compat_fs_qfilestat	qs_uquota;
+	struct compat_fs_qfilestat	qs_gquota;
+	compat_uint_t	qs_incoredqs;
+	compat_int_t	qs_btimelimit;
+	compat_int_t	qs_itimelimit;
+	compat_int_t	qs_rtbtimelimit;
+	__u16		qs_bwarnlimit;
+	__u16		qs_iwarnlimit;
+};
+
+asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
+						qid_t id, void __user *addr)
+{
+	unsigned int cmds;
+	struct if_dqblk __user *dqblk;
+	struct compat_if_dqblk __user *compat_dqblk;
+	struct fs_quota_stat __user *fsqstat;
+	struct compat_fs_quota_stat __user *compat_fsqstat;
+	compat_uint_t data;
+	u16 xdata;
+	long ret;
+
+	cmds = cmd >> SUBCMDSHIFT;
+
+	switch (cmds) {
+	case Q_GETQUOTA:
+		dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
+		compat_dqblk = addr;
+		ret = sys_quotactl(cmd, special, id, dqblk);
+		if (ret)
+			break;
+		if (copy_in_user(compat_dqblk, dqblk, sizeof(*compat_dqblk)) ||
+			get_user(data, &dqblk->dqb_valid) ||
+			put_user(data, &compat_dqblk->dqb_valid))
+			ret = -EFAULT;
+		break;
+	case Q_SETQUOTA:
+		dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
+		compat_dqblk = addr;
+		ret = -EFAULT;
+		if (copy_in_user(dqblk, compat_dqblk, sizeof(*compat_dqblk)) ||
+			get_user(data, &compat_dqblk->dqb_valid) ||
+			put_user(data, &dqblk->dqb_valid))
+			break;
+		ret = sys_quotactl(cmd, special, id, dqblk);
+		break;
+	case Q_XGETQSTAT:
+		fsqstat = compat_alloc_user_space(sizeof(struct fs_quota_stat));
+		compat_fsqstat = addr;
+		ret = sys_quotactl(cmd, special, id, fsqstat);
+		if (ret)
+			break;
+		ret = -EFAULT;
+		/* Copying qs_version, qs_flags, qs_pad */
+		if (copy_in_user(compat_fsqstat, fsqstat,
+			offsetof(struct compat_fs_quota_stat, qs_uquota)))
+			break;
+		/* Copying qs_uquota */
+		if (copy_in_user(&compat_fsqstat->qs_uquota,
+			&fsqstat->qs_uquota,
+			sizeof(compat_fsqstat->qs_uquota)) ||
+			get_user(data, &fsqstat->qs_uquota.qfs_nextents) ||
+			put_user(data, &compat_fsqstat->qs_uquota.qfs_nextents))
+			break;
+		/* Copying qs_gquota */
+		if (copy_in_user(&compat_fsqstat->qs_gquota,
+			&fsqstat->qs_gquota,
+			sizeof(compat_fsqstat->qs_gquota)) ||
+			get_user(data, &fsqstat->qs_gquota.qfs_nextents) ||
+			put_user(data, &compat_fsqstat->qs_gquota.qfs_nextents))
+			break;
+		/* Copying the rest */
+		if (copy_in_user(&compat_fsqstat->qs_incoredqs,
+			&fsqstat->qs_incoredqs,
+			sizeof(struct compat_fs_quota_stat) -
+			offsetof(struct compat_fs_quota_stat, qs_incoredqs)) ||
+			get_user(xdata, &fsqstat->qs_iwarnlimit) ||
+			put_user(xdata, &compat_fsqstat->qs_iwarnlimit))
+			break;
+		ret = 0;
+		break;
+	default:
+		ret = sys_quotactl(cmd, special, id, addr);
+	}
+	return ret;
+}
+#endif
diff --git a/fs/quota/quota_tree.c b/fs/quota/quota_tree.c
new file mode 100644
index 00000000000..953404c95b1
--- /dev/null
+++ b/fs/quota/quota_tree.c
@@ -0,0 +1,645 @@
+/*
+ *	vfsv0 quota IO operations on file
+ */
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/dqblk_v2.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/quotaops.h>
+
+#include <asm/byteorder.h>
+
+#include "quota_tree.h"
+
+MODULE_AUTHOR("Jan Kara");
+MODULE_DESCRIPTION("Quota trie support");
+MODULE_LICENSE("GPL");
+
+#define __QUOTA_QT_PARANOIA
+
+typedef char *dqbuf_t;
+
+static int get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth)
+{
+	unsigned int epb = info->dqi_usable_bs >> 2;
+
+	depth = info->dqi_qtree_depth - depth - 1;
+	while (depth--)
+		id /= epb;
+	return id % epb;
+}
+
+/* Number of entries in one blocks */
+static inline int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info)
+{
+	return (info->dqi_usable_bs - sizeof(struct qt_disk_dqdbheader))
+	       / info->dqi_entry_size;
+}
+
+static dqbuf_t getdqbuf(size_t size)
+{
+	dqbuf_t buf = kmalloc(size, GFP_NOFS);
+	if (!buf)
+		printk(KERN_WARNING "VFS: Not enough memory for quota buffers.\n");
+	return buf;
+}
+
+static inline void freedqbuf(dqbuf_t buf)
+{
+	kfree(buf);
+}
+
+static inline ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, dqbuf_t buf)
+{
+	struct super_block *sb = info->dqi_sb;
+
+	memset(buf, 0, info->dqi_usable_bs);
+	return sb->s_op->quota_read(sb, info->dqi_type, (char *)buf,
+	       info->dqi_usable_bs, blk << info->dqi_blocksize_bits);
+}
+
+static inline ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, dqbuf_t buf)
+{
+	struct super_block *sb = info->dqi_sb;
+
+	return sb->s_op->quota_write(sb, info->dqi_type, (char *)buf,
+	       info->dqi_usable_bs, blk << info->dqi_blocksize_bits);
+}
+
+/* Remove empty block from list and return it */
+static int get_free_dqblk(struct qtree_mem_dqinfo *info)
+{
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
+	int ret, blk;
+
+	if (!buf)
+		return -ENOMEM;
+	if (info->dqi_free_blk) {
+		blk = info->dqi_free_blk;
+		ret = read_blk(info, blk, buf);
+		if (ret < 0)
+			goto out_buf;
+		info->dqi_free_blk = le32_to_cpu(dh->dqdh_next_free);
+	}
+	else {
+		memset(buf, 0, info->dqi_usable_bs);
+		/* Assure block allocation... */
+		ret = write_blk(info, info->dqi_blocks, buf);
+		if (ret < 0)
+			goto out_buf;
+		blk = info->dqi_blocks++;
+	}
+	mark_info_dirty(info->dqi_sb, info->dqi_type);
+	ret = blk;
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Insert empty block to the list */
+static int put_free_dqblk(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk)
+{
+	struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
+	int err;
+
+	dh->dqdh_next_free = cpu_to_le32(info->dqi_free_blk);
+	dh->dqdh_prev_free = cpu_to_le32(0);
+	dh->dqdh_entries = cpu_to_le16(0);
+	err = write_blk(info, blk, buf);
+	if (err < 0)
+		return err;
+	info->dqi_free_blk = blk;
+	mark_info_dirty(info->dqi_sb, info->dqi_type);
+	return 0;
+}
+
+/* Remove given block from the list of blocks with free entries */
+static int remove_free_dqentry(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk)
+{
+	dqbuf_t tmpbuf = getdqbuf(info->dqi_usable_bs);
+	struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
+	uint nextblk = le32_to_cpu(dh->dqdh_next_free);
+	uint prevblk = le32_to_cpu(dh->dqdh_prev_free);
+	int err;
+
+	if (!tmpbuf)
+		return -ENOMEM;
+	if (nextblk) {
+		err = read_blk(info, nextblk, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+		((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free =
+							dh->dqdh_prev_free;
+		err = write_blk(info, nextblk, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+	}
+	if (prevblk) {
+		err = read_blk(info, prevblk, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+		((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_next_free =
+							dh->dqdh_next_free;
+		err = write_blk(info, prevblk, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+	} else {
+		info->dqi_free_entry = nextblk;
+		mark_info_dirty(info->dqi_sb, info->dqi_type);
+	}
+	freedqbuf(tmpbuf);
+	dh->dqdh_next_free = dh->dqdh_prev_free = cpu_to_le32(0);
+	/* No matter whether write succeeds block is out of list */
+	if (write_blk(info, blk, buf) < 0)
+		printk(KERN_ERR "VFS: Can't write block (%u) with free entries.\n", blk);
+	return 0;
+out_buf:
+	freedqbuf(tmpbuf);
+	return err;
+}
+
+/* Insert given block to the beginning of list with free entries */
+static int insert_free_dqentry(struct qtree_mem_dqinfo *info, dqbuf_t buf, uint blk)
+{
+	dqbuf_t tmpbuf = getdqbuf(info->dqi_usable_bs);
+	struct qt_disk_dqdbheader *dh = (struct qt_disk_dqdbheader *)buf;
+	int err;
+
+	if (!tmpbuf)
+		return -ENOMEM;
+	dh->dqdh_next_free = cpu_to_le32(info->dqi_free_entry);
+	dh->dqdh_prev_free = cpu_to_le32(0);
+	err = write_blk(info, blk, buf);
+	if (err < 0)
+		goto out_buf;
+	if (info->dqi_free_entry) {
+		err = read_blk(info, info->dqi_free_entry, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+		((struct qt_disk_dqdbheader *)tmpbuf)->dqdh_prev_free =
+							cpu_to_le32(blk);
+		err = write_blk(info, info->dqi_free_entry, tmpbuf);
+		if (err < 0)
+			goto out_buf;
+	}
+	freedqbuf(tmpbuf);
+	info->dqi_free_entry = blk;
+	mark_info_dirty(info->dqi_sb, info->dqi_type);
+	return 0;
+out_buf:
+	freedqbuf(tmpbuf);
+	return err;
+}
+
+/* Is the entry in the block free? */
+int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk)
+{
+	int i;
+
+	for (i = 0; i < info->dqi_entry_size; i++)
+		if (disk[i])
+			return 0;
+	return 1;
+}
+EXPORT_SYMBOL(qtree_entry_unused);
+
+/* Find space for dquot */
+static uint find_free_dqentry(struct qtree_mem_dqinfo *info,
+			      struct dquot *dquot, int *err)
+{
+	uint blk, i;
+	struct qt_disk_dqdbheader *dh;
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	char *ddquot;
+
+	*err = 0;
+	if (!buf) {
+		*err = -ENOMEM;
+		return 0;
+	}
+	dh = (struct qt_disk_dqdbheader *)buf;
+	if (info->dqi_free_entry) {
+		blk = info->dqi_free_entry;
+		*err = read_blk(info, blk, buf);
+		if (*err < 0)
+			goto out_buf;
+	} else {
+		blk = get_free_dqblk(info);
+		if ((int)blk < 0) {
+			*err = blk;
+			freedqbuf(buf);
+			return 0;
+		}
+		memset(buf, 0, info->dqi_usable_bs);
+		/* This is enough as block is already zeroed and entry list is empty... */
+		info->dqi_free_entry = blk;
+		mark_info_dirty(dquot->dq_sb, dquot->dq_type);
+	}
+	/* Block will be full? */
+	if (le16_to_cpu(dh->dqdh_entries) + 1 >= qtree_dqstr_in_blk(info)) {
+		*err = remove_free_dqentry(info, buf, blk);
+		if (*err < 0) {
+			printk(KERN_ERR "VFS: find_free_dqentry(): Can't "
+			       "remove block (%u) from entry free list.\n",
+			       blk);
+			goto out_buf;
+		}
+	}
+	le16_add_cpu(&dh->dqdh_entries, 1);
+	/* Find free structure in block */
+	for (i = 0, ddquot = ((char *)buf) + sizeof(struct qt_disk_dqdbheader);
+	     i < qtree_dqstr_in_blk(info) && !qtree_entry_unused(info, ddquot);
+	     i++, ddquot += info->dqi_entry_size);
+#ifdef __QUOTA_QT_PARANOIA
+	if (i == qtree_dqstr_in_blk(info)) {
+		printk(KERN_ERR "VFS: find_free_dqentry(): Data block full "
+				"but it shouldn't.\n");
+		*err = -EIO;
+		goto out_buf;
+	}
+#endif
+	*err = write_blk(info, blk, buf);
+	if (*err < 0) {
+		printk(KERN_ERR "VFS: find_free_dqentry(): Can't write quota "
+				"data block %u.\n", blk);
+		goto out_buf;
+	}
+	dquot->dq_off = (blk << info->dqi_blocksize_bits) +
+			sizeof(struct qt_disk_dqdbheader) +
+			i * info->dqi_entry_size;
+	freedqbuf(buf);
+	return blk;
+out_buf:
+	freedqbuf(buf);
+	return 0;
+}
+
+/* Insert reference to structure into the trie */
+static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
+			  uint *treeblk, int depth)
+{
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	int ret = 0, newson = 0, newact = 0;
+	__le32 *ref;
+	uint newblk;
+
+	if (!buf)
+		return -ENOMEM;
+	if (!*treeblk) {
+		ret = get_free_dqblk(info);
+		if (ret < 0)
+			goto out_buf;
+		*treeblk = ret;
+		memset(buf, 0, info->dqi_usable_bs);
+		newact = 1;
+	} else {
+		ret = read_blk(info, *treeblk, buf);
+		if (ret < 0) {
+			printk(KERN_ERR "VFS: Can't read tree quota block "
+					"%u.\n", *treeblk);
+			goto out_buf;
+		}
+	}
+	ref = (__le32 *)buf;
+	newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
+	if (!newblk)
+		newson = 1;
+	if (depth == info->dqi_qtree_depth - 1) {
+#ifdef __QUOTA_QT_PARANOIA
+		if (newblk) {
+			printk(KERN_ERR "VFS: Inserting already present quota "
+					"entry (block %u).\n",
+			       le32_to_cpu(ref[get_index(info,
+						dquot->dq_id, depth)]));
+			ret = -EIO;
+			goto out_buf;
+		}
+#endif
+		newblk = find_free_dqentry(info, dquot, &ret);
+	} else {
+		ret = do_insert_tree(info, dquot, &newblk, depth+1);
+	}
+	if (newson && ret >= 0) {
+		ref[get_index(info, dquot->dq_id, depth)] =
+							cpu_to_le32(newblk);
+		ret = write_blk(info, *treeblk, buf);
+	} else if (newact && ret < 0) {
+		put_free_dqblk(info, buf, *treeblk);
+	}
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Wrapper for inserting quota structure into tree */
+static inline int dq_insert_tree(struct qtree_mem_dqinfo *info,
+				 struct dquot *dquot)
+{
+	int tmp = QT_TREEOFF;
+	return do_insert_tree(info, dquot, &tmp, 0);
+}
+
+/*
+ *	We don't have to be afraid of deadlocks as we never have quotas on quota files...
+ */
+int qtree_write_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
+{
+	int type = dquot->dq_type;
+	struct super_block *sb = dquot->dq_sb;
+	ssize_t ret;
+	dqbuf_t ddquot = getdqbuf(info->dqi_entry_size);
+
+	if (!ddquot)
+		return -ENOMEM;
+
+	/* dq_off is guarded by dqio_mutex */
+	if (!dquot->dq_off) {
+		ret = dq_insert_tree(info, dquot);
+		if (ret < 0) {
+			printk(KERN_ERR "VFS: Error %zd occurred while "
+					"creating quota.\n", ret);
+			freedqbuf(ddquot);
+			return ret;
+		}
+	}
+	spin_lock(&dq_data_lock);
+	info->dqi_ops->mem2disk_dqblk(ddquot, dquot);
+	spin_unlock(&dq_data_lock);
+	ret = sb->s_op->quota_write(sb, type, (char *)ddquot,
+					info->dqi_entry_size, dquot->dq_off);
+	if (ret != info->dqi_entry_size) {
+		printk(KERN_WARNING "VFS: dquota write failed on dev %s\n",
+		       sb->s_id);
+		if (ret >= 0)
+			ret = -ENOSPC;
+	} else {
+		ret = 0;
+	}
+	dqstats.writes++;
+	freedqbuf(ddquot);
+
+	return ret;
+}
+EXPORT_SYMBOL(qtree_write_dquot);
+
+/* Free dquot entry in data block */
+static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot,
+			uint blk)
+{
+	struct qt_disk_dqdbheader *dh;
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	int ret = 0;
+
+	if (!buf)
+		return -ENOMEM;
+	if (dquot->dq_off >> info->dqi_blocksize_bits != blk) {
+		printk(KERN_ERR "VFS: Quota structure has offset to other "
+		  "block (%u) than it should (%u).\n", blk,
+		  (uint)(dquot->dq_off >> info->dqi_blocksize_bits));
+		goto out_buf;
+	}
+	ret = read_blk(info, blk, buf);
+	if (ret < 0) {
+		printk(KERN_ERR "VFS: Can't read quota data block %u\n", blk);
+		goto out_buf;
+	}
+	dh = (struct qt_disk_dqdbheader *)buf;
+	le16_add_cpu(&dh->dqdh_entries, -1);
+	if (!le16_to_cpu(dh->dqdh_entries)) {	/* Block got free? */
+		ret = remove_free_dqentry(info, buf, blk);
+		if (ret >= 0)
+			ret = put_free_dqblk(info, buf, blk);
+		if (ret < 0) {
+			printk(KERN_ERR "VFS: Can't move quota data block (%u) "
+			  "to free list.\n", blk);
+			goto out_buf;
+		}
+	} else {
+		memset(buf +
+		       (dquot->dq_off & ((1 << info->dqi_blocksize_bits) - 1)),
+		       0, info->dqi_entry_size);
+		if (le16_to_cpu(dh->dqdh_entries) ==
+		    qtree_dqstr_in_blk(info) - 1) {
+			/* Insert will write block itself */
+			ret = insert_free_dqentry(info, buf, blk);
+			if (ret < 0) {
+				printk(KERN_ERR "VFS: Can't insert quota data "
+				       "block (%u) to free entry list.\n", blk);
+				goto out_buf;
+			}
+		} else {
+			ret = write_blk(info, blk, buf);
+			if (ret < 0) {
+				printk(KERN_ERR "VFS: Can't write quota data "
+				  "block %u\n", blk);
+				goto out_buf;
+			}
+		}
+	}
+	dquot->dq_off = 0;	/* Quota is now unattached */
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Remove reference to dquot from tree */
+static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
+		       uint *blk, int depth)
+{
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	int ret = 0;
+	uint newblk;
+	__le32 *ref = (__le32 *)buf;
+
+	if (!buf)
+		return -ENOMEM;
+	ret = read_blk(info, *blk, buf);
+	if (ret < 0) {
+		printk(KERN_ERR "VFS: Can't read quota data block %u\n", *blk);
+		goto out_buf;
+	}
+	newblk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
+	if (depth == info->dqi_qtree_depth - 1) {
+		ret = free_dqentry(info, dquot, newblk);
+		newblk = 0;
+	} else {
+		ret = remove_tree(info, dquot, &newblk, depth+1);
+	}
+	if (ret >= 0 && !newblk) {
+		int i;
+		ref[get_index(info, dquot->dq_id, depth)] = cpu_to_le32(0);
+		/* Block got empty? */
+		for (i = 0;
+		     i < (info->dqi_usable_bs >> 2) && !ref[i];
+		     i++);
+		/* Don't put the root block into the free block list */
+		if (i == (info->dqi_usable_bs >> 2)
+		    && *blk != QT_TREEOFF) {
+			put_free_dqblk(info, buf, *blk);
+			*blk = 0;
+		} else {
+			ret = write_blk(info, *blk, buf);
+			if (ret < 0)
+				printk(KERN_ERR "VFS: Can't write quota tree "
+				  "block %u.\n", *blk);
+		}
+	}
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Delete dquot from tree */
+int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
+{
+	uint tmp = QT_TREEOFF;
+
+	if (!dquot->dq_off)	/* Even not allocated? */
+		return 0;
+	return remove_tree(info, dquot, &tmp, 0);
+}
+EXPORT_SYMBOL(qtree_delete_dquot);
+
+/* Find entry in block */
+static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info,
+				 struct dquot *dquot, uint blk)
+{
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	loff_t ret = 0;
+	int i;
+	char *ddquot;
+
+	if (!buf)
+		return -ENOMEM;
+	ret = read_blk(info, blk, buf);
+	if (ret < 0) {
+		printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk);
+		goto out_buf;
+	}
+	for (i = 0, ddquot = ((char *)buf) + sizeof(struct qt_disk_dqdbheader);
+	     i < qtree_dqstr_in_blk(info) && !info->dqi_ops->is_id(ddquot, dquot);
+	     i++, ddquot += info->dqi_entry_size);
+	if (i == qtree_dqstr_in_blk(info)) {
+		printk(KERN_ERR "VFS: Quota for id %u referenced "
+		  "but not present.\n", dquot->dq_id);
+		ret = -EIO;
+		goto out_buf;
+	} else {
+		ret = (blk << info->dqi_blocksize_bits) + sizeof(struct
+		  qt_disk_dqdbheader) + i * info->dqi_entry_size;
+	}
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Find entry for given id in the tree */
+static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info,
+				struct dquot *dquot, uint blk, int depth)
+{
+	dqbuf_t buf = getdqbuf(info->dqi_usable_bs);
+	loff_t ret = 0;
+	__le32 *ref = (__le32 *)buf;
+
+	if (!buf)
+		return -ENOMEM;
+	ret = read_blk(info, blk, buf);
+	if (ret < 0) {
+		printk(KERN_ERR "VFS: Can't read quota tree block %u.\n", blk);
+		goto out_buf;
+	}
+	ret = 0;
+	blk = le32_to_cpu(ref[get_index(info, dquot->dq_id, depth)]);
+	if (!blk)	/* No reference? */
+		goto out_buf;
+	if (depth < info->dqi_qtree_depth - 1)
+		ret = find_tree_dqentry(info, dquot, blk, depth+1);
+	else
+		ret = find_block_dqentry(info, dquot, blk);
+out_buf:
+	freedqbuf(buf);
+	return ret;
+}
+
+/* Find entry for given id in the tree - wrapper function */
+static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info,
+				  struct dquot *dquot)
+{
+	return find_tree_dqentry(info, dquot, QT_TREEOFF, 0);
+}
+
+int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
+{
+	int type = dquot->dq_type;
+	struct super_block *sb = dquot->dq_sb;
+	loff_t offset;
+	dqbuf_t ddquot;
+	int ret = 0;
+
+#ifdef __QUOTA_QT_PARANOIA
+	/* Invalidated quota? */
+	if (!sb_dqopt(dquot->dq_sb)->files[type]) {
+		printk(KERN_ERR "VFS: Quota invalidated while reading!\n");
+		return -EIO;
+	}
+#endif
+	/* Do we know offset of the dquot entry in the quota file? */
+	if (!dquot->dq_off) {
+		offset = find_dqentry(info, dquot);
+		if (offset <= 0) {	/* Entry not present? */
+			if (offset < 0)
+				printk(KERN_ERR "VFS: Can't read quota "
+				  "structure for id %u.\n", dquot->dq_id);
+			dquot->dq_off = 0;
+			set_bit(DQ_FAKE_B, &dquot->dq_flags);
+			memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk));
+			ret = offset;
+			goto out;
+		}
+		dquot->dq_off = offset;
+	}
+	ddquot = getdqbuf(info->dqi_entry_size);
+	if (!ddquot)
+		return -ENOMEM;
+	ret = sb->s_op->quota_read(sb, type, (char *)ddquot,
+				   info->dqi_entry_size, dquot->dq_off);
+	if (ret != info->dqi_entry_size) {
+		if (ret >= 0)
+			ret = -EIO;
+		printk(KERN_ERR "VFS: Error while reading quota "
+				"structure for id %u.\n", dquot->dq_id);
+		set_bit(DQ_FAKE_B, &dquot->dq_flags);
+		memset(&dquot->dq_dqb, 0, sizeof(struct mem_dqblk));
+		freedqbuf(ddquot);
+		goto out;
+	}
+	spin_lock(&dq_data_lock);
+	info->dqi_ops->disk2mem_dqblk(dquot, ddquot);
+	if (!dquot->dq_dqb.dqb_bhardlimit &&
+	    !dquot->dq_dqb.dqb_bsoftlimit &&
+	    !dquot->dq_dqb.dqb_ihardlimit &&
+	    !dquot->dq_dqb.dqb_isoftlimit)
+		set_bit(DQ_FAKE_B, &dquot->dq_flags);
+	spin_unlock(&dq_data_lock);
+	freedqbuf(ddquot);
+out:
+	dqstats.reads++;
+	return ret;
+}
+EXPORT_SYMBOL(qtree_read_dquot);
+
+/* Check whether dquot should not be deleted. We know we are
+ * the only one operating on dquot (thanks to dq_lock) */
+int qtree_release_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
+{
+	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) && !(dquot->dq_dqb.dqb_curinodes | dquot->dq_dqb.dqb_curspace))
+		return qtree_delete_dquot(info, dquot);
+	return 0;
+}
+EXPORT_SYMBOL(qtree_release_dquot);
diff --git a/fs/quota/quota_tree.h b/fs/quota/quota_tree.h
new file mode 100644
index 00000000000..a1ab8db81a5
--- /dev/null
+++ b/fs/quota/quota_tree.h
@@ -0,0 +1,25 @@
+/*
+ *	Definitions of structures for vfsv0 quota format
+ */
+
+#ifndef _LINUX_QUOTA_TREE_H
+#define _LINUX_QUOTA_TREE_H
+
+#include <linux/types.h>
+#include <linux/quota.h>
+
+/*
+ *  Structure of header of block with quota structures. It is padded to 16 bytes so
+ *  there will be space for exactly 21 quota-entries in a block
+ */
+struct qt_disk_dqdbheader {
+	__le32 dqdh_next_free;	/* Number of next block with free entry */
+	__le32 dqdh_prev_free;	/* Number of previous block with free entry */
+	__le16 dqdh_entries;	/* Number of valid entries in block */
+	__le16 dqdh_pad1;
+	__le32 dqdh_pad2;
+};
+
+#define QT_TREEOFF	1		/* Offset of tree in file in blocks */
+
+#endif /* _LINUX_QUOTAIO_TREE_H */
diff --git a/fs/quota/quota_v1.c b/fs/quota/quota_v1.c
new file mode 100644
index 00000000000..b4af1c69ad1
--- /dev/null
+++ b/fs/quota/quota_v1.c
@@ -0,0 +1,218 @@
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/quota.h>
+#include <linux/quotaops.h>
+#include <linux/dqblk_v1.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/byteorder.h>
+
+#include "quotaio_v1.h"
+
+MODULE_AUTHOR("Jan Kara");
+MODULE_DESCRIPTION("Old quota format support");
+MODULE_LICENSE("GPL");
+
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v1_stoqb(qsize_t space)
+{
+	return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v1_qbtos(qsize_t blocks)
+{
+	return blocks << QUOTABLOCK_BITS;
+}
+
+static void v1_disk2mem_dqblk(struct mem_dqblk *m, struct v1_disk_dqblk *d)
+{
+	m->dqb_ihardlimit = d->dqb_ihardlimit;
+	m->dqb_isoftlimit = d->dqb_isoftlimit;
+	m->dqb_curinodes = d->dqb_curinodes;
+	m->dqb_bhardlimit = v1_qbtos(d->dqb_bhardlimit);
+	m->dqb_bsoftlimit = v1_qbtos(d->dqb_bsoftlimit);
+	m->dqb_curspace = v1_qbtos(d->dqb_curblocks);
+	m->dqb_itime = d->dqb_itime;
+	m->dqb_btime = d->dqb_btime;
+}
+
+static void v1_mem2disk_dqblk(struct v1_disk_dqblk *d, struct mem_dqblk *m)
+{
+	d->dqb_ihardlimit = m->dqb_ihardlimit;
+	d->dqb_isoftlimit = m->dqb_isoftlimit;
+	d->dqb_curinodes = m->dqb_curinodes;
+	d->dqb_bhardlimit = v1_stoqb(m->dqb_bhardlimit);
+	d->dqb_bsoftlimit = v1_stoqb(m->dqb_bsoftlimit);
+	d->dqb_curblocks = v1_stoqb(m->dqb_curspace);
+	d->dqb_itime = m->dqb_itime;
+	d->dqb_btime = m->dqb_btime;
+}
+
+static int v1_read_dqblk(struct dquot *dquot)
+{
+	int type = dquot->dq_type;
+	struct v1_disk_dqblk dqblk;
+
+	if (!sb_dqopt(dquot->dq_sb)->files[type])
+		return -EINVAL;
+
+	/* Set structure to 0s in case read fails/is after end of file */
+	memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
+	dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
+
+	v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
+	if (dquot->dq_dqb.dqb_bhardlimit == 0 && dquot->dq_dqb.dqb_bsoftlimit == 0 &&
+	    dquot->dq_dqb.dqb_ihardlimit == 0 && dquot->dq_dqb.dqb_isoftlimit == 0)
+		set_bit(DQ_FAKE_B, &dquot->dq_flags);
+	dqstats.reads++;
+
+	return 0;
+}
+
+static int v1_commit_dqblk(struct dquot *dquot)
+{
+	short type = dquot->dq_type;
+	ssize_t ret;
+	struct v1_disk_dqblk dqblk;
+
+	v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
+	if (dquot->dq_id == 0) {
+		dqblk.dqb_btime = sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
+		dqblk.dqb_itime = sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
+	}
+	ret = 0;
+	if (sb_dqopt(dquot->dq_sb)->files[type])
+		ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type, (char *)&dqblk,
+					sizeof(struct v1_disk_dqblk), v1_dqoff(dquot->dq_id));
+	if (ret != sizeof(struct v1_disk_dqblk)) {
+		printk(KERN_WARNING "VFS: dquota write failed on dev %s\n",
+			dquot->dq_sb->s_id);
+		if (ret >= 0)
+			ret = -EIO;
+		goto out;
+	}
+	ret = 0;
+
+out:
+	dqstats.writes++;
+
+	return ret;
+}
+
+/* Magics of new quota format */
+#define V2_INITQMAGICS {\
+	0xd9c01f11,     /* USRQUOTA */\
+	0xd9c01927      /* GRPQUOTA */\
+}
+
+/* Header of new quota format */
+struct v2_disk_dqheader {
+	__le32 dqh_magic;        /* Magic number identifying file */
+	__le32 dqh_version;      /* File version */
+};
+
+static int v1_check_quota_file(struct super_block *sb, int type)
+{
+	struct inode *inode = sb_dqopt(sb)->files[type];
+	ulong blocks;
+	size_t off; 
+	struct v2_disk_dqheader dqhead;
+	ssize_t size;
+	loff_t isize;
+	static const uint quota_magics[] = V2_INITQMAGICS;
+
+	isize = i_size_read(inode);
+	if (!isize)
+		return 0;
+	blocks = isize >> BLOCK_SIZE_BITS;
+	off = isize & (BLOCK_SIZE - 1);
+	if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) % sizeof(struct v1_disk_dqblk))
+		return 0;
+	/* Doublecheck whether we didn't get file with new format - with old quotactl() this could happen */
+	size = sb->s_op->quota_read(sb, type, (char *)&dqhead, sizeof(struct v2_disk_dqheader), 0);
+	if (size != sizeof(struct v2_disk_dqheader))
+		return 1;	/* Probably not new format */
+	if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
+		return 1;	/* Definitely not new format */
+	printk(KERN_INFO "VFS: %s: Refusing to turn on old quota format on given file. It probably contains newer quota format.\n", sb->s_id);
+        return 0;		/* Seems like a new format file -> refuse it */
+}
+
+static int v1_read_file_info(struct super_block *sb, int type)
+{
+	struct quota_info *dqopt = sb_dqopt(sb);
+	struct v1_disk_dqblk dqblk;
+	int ret;
+
+	if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk, sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
+		if (ret >= 0)
+			ret = -EIO;
+		goto out;
+	}
+	ret = 0;
+	/* limits are stored as unsigned 32-bit data */
+	dqopt->info[type].dqi_maxblimit = 0xffffffff;
+	dqopt->info[type].dqi_maxilimit = 0xffffffff;
+	dqopt->info[type].dqi_igrace = dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
+	dqopt->info[type].dqi_bgrace = dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
+out:
+	return ret;
+}
+
+static int v1_write_file_info(struct super_block *sb, int type)
+{
+	struct quota_info *dqopt = sb_dqopt(sb);
+	struct v1_disk_dqblk dqblk;
+	int ret;
+
+	dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
+	if ((ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
+	    sizeof(struct v1_disk_dqblk), v1_dqoff(0))) != sizeof(struct v1_disk_dqblk)) {
+		if (ret >= 0)
+			ret = -EIO;
+		goto out;
+	}
+	dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
+	dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
+	ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
+	      sizeof(struct v1_disk_dqblk), v1_dqoff(0));
+	if (ret == sizeof(struct v1_disk_dqblk))
+		ret = 0;
+	else if (ret > 0)
+		ret = -EIO;
+out:
+	return ret;
+}
+
+static struct quota_format_ops v1_format_ops = {
+	.check_quota_file	= v1_check_quota_file,
+	.read_file_info		= v1_read_file_info,
+	.write_file_info	= v1_write_file_info,
+	.free_file_info		= NULL,
+	.read_dqblk		= v1_read_dqblk,
+	.commit_dqblk		= v1_commit_dqblk,
+};
+
+static struct quota_format_type v1_quota_format = {
+	.qf_fmt_id	= QFMT_VFS_OLD,
+	.qf_ops		= &v1_format_ops,
+	.qf_owner	= THIS_MODULE
+};
+
+static int __init init_v1_quota_format(void)
+{
+        return register_quota_format(&v1_quota_format);
+}
+
+static void __exit exit_v1_quota_format(void)
+{
+        unregister_quota_format(&v1_quota_format);
+}
+
+module_init(init_v1_quota_format);
+module_exit(exit_v1_quota_format);
+
diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c
new file mode 100644
index 00000000000..b618b563635
--- /dev/null
+++ b/fs/quota/quota_v2.c
@@ -0,0 +1,236 @@
+/*
+ *	vfsv0 quota IO operations on file
+ */
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/dqblk_v2.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/quotaops.h>
+
+#include <asm/byteorder.h>
+
+#include "quota_tree.h"
+#include "quotaio_v2.h"
+
+MODULE_AUTHOR("Jan Kara");
+MODULE_DESCRIPTION("Quota format v2 support");
+MODULE_LICENSE("GPL");
+
+#define __QUOTA_V2_PARANOIA
+
+static void v2_mem2diskdqb(void *dp, struct dquot *dquot);
+static void v2_disk2memdqb(struct dquot *dquot, void *dp);
+static int v2_is_id(void *dp, struct dquot *dquot);
+
+static struct qtree_fmt_operations v2_qtree_ops = {
+	.mem2disk_dqblk = v2_mem2diskdqb,
+	.disk2mem_dqblk = v2_disk2memdqb,
+	.is_id = v2_is_id,
+};
+
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v2_stoqb(qsize_t space)
+{
+	return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v2_qbtos(qsize_t blocks)
+{
+	return blocks << QUOTABLOCK_BITS;
+}
+
+/* Check whether given file is really vfsv0 quotafile */
+static int v2_check_quota_file(struct super_block *sb, int type)
+{
+	struct v2_disk_dqheader dqhead;
+	ssize_t size;
+	static const uint quota_magics[] = V2_INITQMAGICS;
+	static const uint quota_versions[] = V2_INITQVERSIONS;
+ 
+	size = sb->s_op->quota_read(sb, type, (char *)&dqhead, sizeof(struct v2_disk_dqheader), 0);
+	if (size != sizeof(struct v2_disk_dqheader)) {
+		printk("quota_v2: failed read expected=%zd got=%zd\n",
+			sizeof(struct v2_disk_dqheader), size);
+		return 0;
+	}
+	if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
+	    le32_to_cpu(dqhead.dqh_version) != quota_versions[type])
+		return 0;
+	return 1;
+}
+
+/* Read information header from quota file */
+static int v2_read_file_info(struct super_block *sb, int type)
+{
+	struct v2_disk_dqinfo dinfo;
+	struct mem_dqinfo *info = sb_dqinfo(sb, type);
+	struct qtree_mem_dqinfo *qinfo;
+	ssize_t size;
+
+	size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
+	       sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
+	if (size != sizeof(struct v2_disk_dqinfo)) {
+		printk(KERN_WARNING "Can't read info structure on device %s.\n",
+			sb->s_id);
+		return -1;
+	}
+	info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
+	if (!info->dqi_priv) {
+		printk(KERN_WARNING
+		       "Not enough memory for quota information structure.\n");
+		return -1;
+	}
+	qinfo = info->dqi_priv;
+	/* limits are stored as unsigned 32-bit data */
+	info->dqi_maxblimit = 0xffffffff;
+	info->dqi_maxilimit = 0xffffffff;
+	info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
+	info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
+	info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
+	qinfo->dqi_sb = sb;
+	qinfo->dqi_type = type;
+	qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
+	qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
+	qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
+	qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
+	qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
+	qinfo->dqi_qtree_depth = qtree_depth(qinfo);
+	qinfo->dqi_entry_size = sizeof(struct v2_disk_dqblk);
+	qinfo->dqi_ops = &v2_qtree_ops;
+	return 0;
+}
+
+/* Write information header to quota file */
+static int v2_write_file_info(struct super_block *sb, int type)
+{
+	struct v2_disk_dqinfo dinfo;
+	struct mem_dqinfo *info = sb_dqinfo(sb, type);
+	struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
+	ssize_t size;
+
+	spin_lock(&dq_data_lock);
+	info->dqi_flags &= ~DQF_INFO_DIRTY;
+	dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
+	dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
+	dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
+	spin_unlock(&dq_data_lock);
+	dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
+	dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
+	dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
+	size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
+	       sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
+	if (size != sizeof(struct v2_disk_dqinfo)) {
+		printk(KERN_WARNING "Can't write info structure on device %s.\n",
+			sb->s_id);
+		return -1;
+	}
+	return 0;
+}
+
+static void v2_disk2memdqb(struct dquot *dquot, void *dp)
+{
+	struct v2_disk_dqblk *d = dp, empty;
+	struct mem_dqblk *m = &dquot->dq_dqb;
+
+	m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
+	m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
+	m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
+	m->dqb_itime = le64_to_cpu(d->dqb_itime);
+	m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
+	m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
+	m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
+	m->dqb_btime = le64_to_cpu(d->dqb_btime);
+	/* We need to escape back all-zero structure */
+	memset(&empty, 0, sizeof(struct v2_disk_dqblk));
+	empty.dqb_itime = cpu_to_le64(1);
+	if (!memcmp(&empty, dp, sizeof(struct v2_disk_dqblk)))
+		m->dqb_itime = 0;
+}
+
+static void v2_mem2diskdqb(void *dp, struct dquot *dquot)
+{
+	struct v2_disk_dqblk *d = dp;
+	struct mem_dqblk *m = &dquot->dq_dqb;
+	struct qtree_mem_dqinfo *info =
+			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
+
+	d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
+	d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
+	d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
+	d->dqb_itime = cpu_to_le64(m->dqb_itime);
+	d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
+	d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
+	d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
+	d->dqb_btime = cpu_to_le64(m->dqb_btime);
+	d->dqb_id = cpu_to_le32(dquot->dq_id);
+	if (qtree_entry_unused(info, dp))
+		d->dqb_itime = cpu_to_le64(1);
+}
+
+static int v2_is_id(void *dp, struct dquot *dquot)
+{
+	struct v2_disk_dqblk *d = dp;
+	struct qtree_mem_dqinfo *info =
+			sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
+
+	if (qtree_entry_unused(info, dp))
+		return 0;
+	return le32_to_cpu(d->dqb_id) == dquot->dq_id;
+}
+
+static int v2_read_dquot(struct dquot *dquot)
+{
+	return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_write_dquot(struct dquot *dquot)
+{
+	return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_release_dquot(struct dquot *dquot)
+{
+	return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_free_file_info(struct super_block *sb, int type)
+{
+	kfree(sb_dqinfo(sb, type)->dqi_priv);
+	return 0;
+}
+
+static struct quota_format_ops v2_format_ops = {
+	.check_quota_file	= v2_check_quota_file,
+	.read_file_info		= v2_read_file_info,
+	.write_file_info	= v2_write_file_info,
+	.free_file_info		= v2_free_file_info,
+	.read_dqblk		= v2_read_dquot,
+	.commit_dqblk		= v2_write_dquot,
+	.release_dqblk		= v2_release_dquot,
+};
+
+static struct quota_format_type v2_quota_format = {
+	.qf_fmt_id	= QFMT_VFS_V0,
+	.qf_ops		= &v2_format_ops,
+	.qf_owner	= THIS_MODULE
+};
+
+static int __init init_v2_quota_format(void)
+{
+	return register_quota_format(&v2_quota_format);
+}
+
+static void __exit exit_v2_quota_format(void)
+{
+	unregister_quota_format(&v2_quota_format);
+}
+
+module_init(init_v2_quota_format);
+module_exit(exit_v2_quota_format);
diff --git a/fs/quota/quotaio_v1.h b/fs/quota/quotaio_v1.h
new file mode 100644
index 00000000000..746654b5de7
--- /dev/null
+++ b/fs/quota/quotaio_v1.h
@@ -0,0 +1,33 @@
+#ifndef _LINUX_QUOTAIO_V1_H
+#define _LINUX_QUOTAIO_V1_H
+
+#include <linux/types.h>
+
+/*
+ * The following constants define the amount of time given a user
+ * before the soft limits are treated as hard limits (usually resulting
+ * in an allocation failure). The timer is started when the user crosses
+ * their soft limit, it is reset when they go below their soft limit.
+ */
+#define MAX_IQ_TIME  604800	/* (7*24*60*60) 1 week */
+#define MAX_DQ_TIME  604800	/* (7*24*60*60) 1 week */
+
+/*
+ * The following structure defines the format of the disk quota file
+ * (as it appears on disk) - the file is an array of these structures
+ * indexed by user or group number.
+ */
+struct v1_disk_dqblk {
+	__u32 dqb_bhardlimit;	/* absolute limit on disk blks alloc */
+	__u32 dqb_bsoftlimit;	/* preferred limit on disk blks */
+	__u32 dqb_curblocks;	/* current block count */
+	__u32 dqb_ihardlimit;	/* absolute limit on allocated inodes */
+	__u32 dqb_isoftlimit;	/* preferred inode limit */
+	__u32 dqb_curinodes;	/* current # allocated inodes */
+	time_t dqb_btime;	/* time limit for excessive disk use */
+	time_t dqb_itime;	/* time limit for excessive inode use */
+};
+
+#define v1_dqoff(UID)      ((loff_t)((UID) * sizeof (struct v1_disk_dqblk)))
+
+#endif	/* _LINUX_QUOTAIO_V1_H */
diff --git a/fs/quota/quotaio_v2.h b/fs/quota/quotaio_v2.h
new file mode 100644
index 00000000000..530fe580685
--- /dev/null
+++ b/fs/quota/quotaio_v2.h
@@ -0,0 +1,60 @@
+/*
+ *	Definitions of structures for vfsv0 quota format
+ */
+
+#ifndef _LINUX_QUOTAIO_V2_H
+#define _LINUX_QUOTAIO_V2_H
+
+#include <linux/types.h>
+#include <linux/quota.h>
+
+/*
+ * Definitions of magics and versions of current quota files
+ */
+#define V2_INITQMAGICS {\
+	0xd9c01f11,	/* USRQUOTA */\
+	0xd9c01927	/* GRPQUOTA */\
+}
+
+#define V2_INITQVERSIONS {\
+	0,		/* USRQUOTA */\
+	0		/* GRPQUOTA */\
+}
+
+/* First generic header */
+struct v2_disk_dqheader {
+	__le32 dqh_magic;	/* Magic number identifying file */
+	__le32 dqh_version;	/* File version */
+};
+
+/*
+ * The following structure defines the format of the disk quota file
+ * (as it appears on disk) - the file is a radix tree whose leaves point
+ * to blocks of these structures.
+ */
+struct v2_disk_dqblk {
+	__le32 dqb_id;		/* id this quota applies to */
+	__le32 dqb_ihardlimit;	/* absolute limit on allocated inodes */
+	__le32 dqb_isoftlimit;	/* preferred inode limit */
+	__le32 dqb_curinodes;	/* current # allocated inodes */
+	__le32 dqb_bhardlimit;	/* absolute limit on disk space (in QUOTABLOCK_SIZE) */
+	__le32 dqb_bsoftlimit;	/* preferred limit on disk space (in QUOTABLOCK_SIZE) */
+	__le64 dqb_curspace;	/* current space occupied (in bytes) */
+	__le64 dqb_btime;	/* time limit for excessive disk use */
+	__le64 dqb_itime;	/* time limit for excessive inode use */
+};
+
+/* Header with type and version specific information */
+struct v2_disk_dqinfo {
+	__le32 dqi_bgrace;	/* Time before block soft limit becomes hard limit */
+	__le32 dqi_igrace;	/* Time before inode soft limit becomes hard limit */
+	__le32 dqi_flags;	/* Flags for quotafile (DQF_*) */
+	__le32 dqi_blocks;	/* Number of blocks in file */
+	__le32 dqi_free_blk;	/* Number of first free block in the list */
+	__le32 dqi_free_entry;	/* Number of block with at least one free entry */
+};
+
+#define V2_DQINFOOFF	sizeof(struct v2_disk_dqheader)	/* Offset of info header in file */
+#define V2_DQBLKSIZE_BITS 10				/* Size of leaf block in tree */
+
+#endif /* _LINUX_QUOTAIO_V2_H */