// SPDX-License-Identifier: GPL-2.0

  /*
   * 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/sched.h>

  #include <linux/cred.h>

  #include <linux/kmod.h>
  #include <linux/namei.h>

  #include <linux/capability.h>

  #include <linux/quotaops.h>

  #include "../internal.h" /* ugh */

  #include <linux/uaccess.h>

  /*

   * There are five quota SMP locks:
   * * dq_list_lock protects all lists with quotas and quota formats.
   * * dquot->dq_dqb_lock protects data from dq_dqb
   * * inode->i_lock protects inode->i_blocks, i_bytes and also guards
   *   consistency of dquot->dq_dqb with inode->i_blocks, i_bytes so that
   *   dquot_transfer() can stabilize amount it transfers
   * * dq_data_lock protects mem_dqinfo structures and modifications of dquot
   *   pointers in the inode
   * * 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 > dquot->dq_dqb_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
   *

   * Operation accessing dquots via inode pointers are protected by dquot_srcu.
   * Operation of reading pointer needs srcu_read_lock(&dquot_srcu), and
   * synchronize_srcu(&dquot_srcu) is called after clearing pointers from
   * inode and before dropping dquot references to avoid use of dquots after
   * they are freed. dq_data_lock is used to serialize the pointer setting and
   * clearing operations.

   * Special care needs to be taken about S_NOQUOTA inode flag (marking that
   * inode is a quota file). Functions adding pointers from inode to dquots have

   * to check this flag under dq_data_lock and then (if S_NOQUOTA is not set) they
   * have to do all pointer modifications before dropping dq_data_lock. This makes

   * sure they cannot race with quotaon which first sets S_NOQUOTA flag and
   * then drops all pointers to dquots from an inode.

   *

   * Each dquot has its dq_lock mutex.  Dquot is locked when it is being read to
   * memory (or space for it is being allocated) on the first dqget(), when it is
   * being written out, and when it is being released on the last dqput(). The
   * allocation and release operations are serialized by the dq_lock and by
   * checking the use count in dquot_release().

   *
   * Lock ordering (including related VFS locks) is the following:

   *   s_umount > i_mutex > journal_lock > dquot->dq_lock > dqio_sem

   */

  static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
  static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
  __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);

  EXPORT_SYMBOL(dq_data_lock);

  DEFINE_STATIC_SRCU(dquot_srcu);

  static DECLARE_WAIT_QUEUE_HEAD(dquot_ref_wq);

  void __quota_error(struct super_block *sb, const char *func,

  		   const char *fmt, ...)

  {

  	if (printk_ratelimit()) {

  		va_list args;
  		struct va_format vaf;

  		va_start(args, fmt);

  
  		vaf.fmt = fmt;
  		vaf.va = &args;
  
  		printk(KERN_ERR "Quota error (device %s): %s: %pV
  ",
  		       sb->s_id, func, &vaf);

  		va_end(args);
  	}
  }
  EXPORT_SYMBOL(__quota_error);

  #if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING)

  static char *quotatypes[] = INITQFNAMES;

  #endif

  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 four lists for dquot management: the inuse_list,
   * free_dquots, dqi_dirty_list, and dquot_hash[] array. A single dquot
   * structure may be on some of those 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.
   *

   * Dirty dquots are added to the dqi_dirty_list of quota_info when mark
   * dirtied, and this list is searched when writing dirty dquots back to
   * quota file. Note that some filesystems do dirty dquot tracking on their
   * own (e.g. in a journal) and thus don't use dqi_dirty_list.
   *

   * 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 qsize_t inode_get_rsv_space(struct inode *inode);

  static qsize_t __inode_get_rsv_space(struct inode *inode);

  static int __dquot_initialize(struct inode *inode, int type);

  static inline unsigned int

  hashfn(const struct super_block *sb, struct kqid qid)

  {

  	unsigned int id = from_kqid(&init_user_ns, qid);
  	int type = qid.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;

  	head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id);

  	hlist_add_head(&dquot->dq_hash, head);
  }
  
  static inline void remove_dquot_hash(struct dquot *dquot)
  {
  	hlist_del_init(&dquot->dq_hash);
  }

  static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,

  				struct kqid qid)

  {
  	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 && qid_eq(dquot->dq_id, qid))

  			return dquot;
  	}

  	return NULL;

  }
  
  /* 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_inc(DQST_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_dec(DQST_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_inc(DQST_ALLOC_DQUOTS);

  }
  
  static inline void remove_inuse(struct dquot *dquot)
  {

  	dqstats_dec(DQST_ALLOC_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);
  }

  /* Mark dquot dirty in atomic manner, and return it's old dirty flag state */

  int dquot_mark_dquot_dirty(struct dquot *dquot)
  {

  	int ret = 1;

  	if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
  		return 0;

  	if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NOLIST_DIRTY)
  		return test_and_set_bit(DQ_MOD_B, &dquot->dq_flags);

  	/* If quota is dirty already, we don't have to acquire dq_list_lock */
  	if (test_bit(DQ_MOD_B, &dquot->dq_flags))
  		return 1;

  	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_id.type].dqi_dirty_list);

  		ret = 0;
  	}

  	spin_unlock(&dq_list_lock);

  	return ret;

  }

  EXPORT_SYMBOL(dquot_mark_dquot_dirty);

  /* Dirtify all the dquots - this can block when journalling */
  static inline int mark_all_dquot_dirty(struct dquot * const *dquot)
  {
  	int ret, err, cnt;
  
  	ret = err = 0;
  	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
  		if (dquot[cnt])
  			/* Even in case of error we have to continue */
  			ret = mark_dquot_dirty(dquot[cnt]);
  		if (!err)
  			err = ret;
  	}
  	return err;
  }
  
  static inline void dqput_all(struct dquot **dquot)
  {
  	unsigned int cnt;
  
  	for (cnt = 0; cnt < MAXQUOTAS; cnt++)
  		dqput(dquot[cnt]);
  }

  static inline int clear_dquot_dirty(struct dquot *dquot)
  {

  	if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NOLIST_DIRTY)
  		return test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags);

  	spin_lock(&dq_list_lock);
  	if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) {
  		spin_unlock(&dq_list_lock);

  		return 0;

  	}

  	list_del_init(&dquot->dq_dirty);

  	spin_unlock(&dq_list_lock);

  	return 1;
  }
  
  void mark_info_dirty(struct super_block *sb, int type)
  {

  	spin_lock(&dq_data_lock);
  	sb_dqopt(sb)->info[type].dqi_flags |= DQF_INFO_DIRTY;
  	spin_unlock(&dq_data_lock);

  }
  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);

  	if (!test_bit(DQ_READ_B, &dquot->dq_flags)) {

  		ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot);

  		if (ret < 0)
  			goto out_iolock;
  	}

  	/* Make sure flags update is visible after dquot has been filled */
  	smp_mb__before_atomic();

  	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_id.type]->commit_dqblk(dquot);

  		/* Write the info if needed */

  		if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
  			ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
  					dquot->dq_sb, dquot->dq_id.type);

  		}

  		if (ret < 0)
  			goto out_iolock;
  		if (ret2 < 0) {
  			ret = ret2;
  			goto out_iolock;
  		}
  	}

  	/*
  	 * Make sure flags update is visible after on-disk struct has been
  	 * allocated. Paired with smp_rmb() in dqget().
  	 */
  	smp_mb__before_atomic();

  	set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
  out_iolock:

  	mutex_unlock(&dquot->dq_lock);

  	return ret;
  }

  EXPORT_SYMBOL(dquot_acquire);

  
  /*
   *	Write dquot to disk
   */
  int dquot_commit(struct dquot *dquot)
  {

  	int ret = 0;

  	struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);

  	mutex_lock(&dquot->dq_lock);

  	if (!clear_dquot_dirty(dquot))

  		goto out_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_id.type]->commit_dqblk(dquot);

  	else
  		ret = -EIO;

  out_lock:
  	mutex_unlock(&dquot->dq_lock);

  	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 (dquot_is_busy(dquot))

  		goto out_dqlock;

  	if (dqopt->ops[dquot->dq_id.type]->release_dqblk) {
  		ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot);

  		/* Write the info */

  		if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
  			ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
  						dquot->dq_sb, dquot->dq_id.type);

  		}

  		if (ret >= 0)
  			ret = ret2;
  	}
  	clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);

  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_id.type != type)

  			continue;

  		/* Wait for dquot users */
  		if (atomic_read(&dquot->dq_count)) {

  			dqgrab(dquot);

  			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.
  			 */

  			wait_event(dquot_ref_wq,
  				   atomic_read(&dquot->dq_count) == 1);

  			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;

  	WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));

  	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);

  		spin_unlock(&dq_list_lock);
  		dqput(old_dquot);
  		old_dquot = dquot;

  		/*
  		 * ->release_dquot() can be racing with us. Our reference
  		 * protects us from new calls to it so just wait for any
  		 * outstanding call and recheck the DQ_ACTIVE_B after that.
  		 */
  		wait_on_dquot(dquot);
  		if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
  			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);

  	return ret;
  }

  EXPORT_SYMBOL(dquot_scan_active);

  /* Write all dquot structures to quota files */
  int dquot_writeback_dquots(struct super_block *sb, int type)

  {

  	struct list_head dirty;

  	struct dquot *dquot;
  	struct quota_info *dqopt = sb_dqopt(sb);
  	int cnt;

  	int err, ret = 0;

  	WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));

  	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);

  		/* Move list away to avoid livelock. */
  		list_replace_init(&dqopt->info[cnt].dqi_dirty_list, &dirty);
  		while (!list_empty(&dirty)) {
  			dquot = list_first_entry(&dirty, struct dquot,

  						 dq_dirty);

  
  			WARN_ON(!test_bit(DQ_ACTIVE_B, &dquot->dq_flags));

  			/* Now we have active dquot from which someone is
   			 * holding reference so we can safely just increase
  			 * use count */

  			dqgrab(dquot);

  			spin_unlock(&dq_list_lock);

  			err = sb->dq_op->write_dquot(dquot);

  			if (err) {
  				/*
  				 * Clear dirty bit anyway to avoid infinite
  				 * loop here.
  				 */
  				clear_dquot_dirty(dquot);
  				if (!ret)
  					ret = err;
  			}

  			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);

  	dqstats_inc(DQST_SYNCS);

  	return ret;
  }
  EXPORT_SYMBOL(dquot_writeback_dquots);
  
  /* Write all dquot structures to disk and make them visible from userspace */
  int dquot_quota_sync(struct super_block *sb, int type)
  {
  	struct quota_info *dqopt = sb_dqopt(sb);
  	int cnt;
  	int ret;
  
  	ret = dquot_writeback_dquots(sb, type);
  	if (ret)
  		return ret;
  	if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)

  		return 0;
  
  	/* 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.
  	 */

  	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
  		if (type != -1 && cnt != type)
  			continue;
  		if (!sb_has_quota_active(sb, cnt))
  			continue;

  		inode_lock(dqopt->files[cnt]);

  		truncate_inode_pages(&dqopt->files[cnt]->i_data, 0);

  		inode_unlock(dqopt->files[cnt]);

  	}

  	return 0;
  }

  EXPORT_SYMBOL(dquot_quota_sync);

  static unsigned long
  dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)

  {

  	struct dquot *dquot;

  	unsigned long freed = 0;

  	spin_lock(&dq_list_lock);

  	while (!list_empty(&free_dquots) && sc->nr_to_scan) {
  		dquot = list_first_entry(&free_dquots, struct dquot, dq_free);

  		remove_dquot_hash(dquot);
  		remove_free_dquot(dquot);
  		remove_inuse(dquot);

  		do_destroy_dquot(dquot);

  		sc->nr_to_scan--;
  		freed++;

  	}

  	spin_unlock(&dq_list_lock);

  	return freed;

  }

  static unsigned long
  dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)

  {

  	return vfs_pressure_ratio(
  	percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]));

  }

  static struct shrinker dqcache_shrinker = {

  	.count_objects = dqcache_shrink_count,
  	.scan_objects = dqcache_shrink_scan,

  	.seeks = DEFAULT_SEEKS,
  };

  /*
   * Put reference to dquot

   */

  void dqput(struct dquot *dquot)

  {

  	int ret;

  	if (!dquot)
  		return;

  #ifdef CONFIG_QUOTA_DEBUG

  	if (!atomic_read(&dquot->dq_count)) {

  		quota_error(dquot->dq_sb, "trying to free free dquot of %s %d",

  			    quotatypes[dquot->dq_id.type],
  			    from_kqid(&init_user_ns, dquot->dq_id));

  		BUG();
  	}
  #endif

  	dqstats_inc(DQST_DROPS);

  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_id.type) &&

  		    atomic_read(&dquot->dq_count) == 1)

  			wake_up(&dquot_ref_wq);

  		spin_unlock(&dq_list_lock);
  		return;
  	}
  	/* Need to release dquot? */

  	if (dquot_dirty(dquot)) {

  		spin_unlock(&dq_list_lock);
  		/* Commit dquot before releasing */

  		ret = dquot->dq_sb->dq_op->write_dquot(dquot);
  		if (ret < 0) {

  			quota_error(dquot->dq_sb, "Can't write quota structure"
  				    " (error %d). Quota may get out of sync!",
  				    ret);

  			/*
  			 * We clear dirty bit anyway, so that we avoid
  			 * infinite loop here
  			 */

  			clear_dquot_dirty(dquot);

  		}

  		goto we_slept;
  	}

  	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 CONFIG_QUOTA_DEBUG

  	/* 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 NULL;

  	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);
  	dquot->dq_sb = sb;

  	dquot->dq_id = make_kqid_invalid(type);

  	atomic_set(&dquot->dq_count, 1);

  	spin_lock_init(&dquot->dq_dqb_lock);

  
  	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, struct kqid qid)

  {

  	unsigned int hashent = hashfn(sb, qid);

  	struct dquot *dquot, *empty = NULL;

  	if (!qid_has_mapping(sb->s_user_ns, qid))
  		return ERR_PTR(-EINVAL);

          if (!sb_has_quota_active(sb, qid.type))

  		return ERR_PTR(-ESRCH);

  we_slept:
  	spin_lock(&dq_list_lock);

  	spin_lock(&dq_state_lock);

  	if (!sb_has_quota_active(sb, qid.type)) {

  		spin_unlock(&dq_state_lock);
  		spin_unlock(&dq_list_lock);

  		dquot = ERR_PTR(-ESRCH);

  		goto out;
  	}
  	spin_unlock(&dq_state_lock);

  	dquot = find_dquot(hashent, sb, qid);

  	if (!dquot) {
  		if (!empty) {

  			spin_unlock(&dq_list_lock);

  			empty = get_empty_dquot(sb, qid.type);

  			if (!empty)

  				schedule();	/* Try to wait for a moment... */
  			goto we_slept;
  		}
  		dquot = empty;

  		empty = NULL;

  		dquot->dq_id = qid;

  		/* all dquots go on the inuse_list */
  		put_inuse(dquot);
  		/* hash it first so it can be found */
  		insert_dquot_hash(dquot);

  		spin_unlock(&dq_list_lock);

  		dqstats_inc(DQST_LOOKUPS);

  	} else {
  		if (!atomic_read(&dquot->dq_count))
  			remove_free_dquot(dquot);
  		atomic_inc(&dquot->dq_count);

  		spin_unlock(&dq_list_lock);

  		dqstats_inc(DQST_CACHE_HITS);
  		dqstats_inc(DQST_LOOKUPS);

  	}

  	/* 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 / allocate space in quota file */

  	if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
  		int err;
  
  		err = sb->dq_op->acquire_dquot(dquot);
  		if (err < 0) {
  			dqput(dquot);
  			dquot = ERR_PTR(err);
  			goto out;
  		}

  	}

  	/*
  	 * Make sure following reads see filled structure - paired with
  	 * smp_mb__before_atomic() in dquot_acquire().
  	 */
  	smp_rmb();

  #ifdef CONFIG_QUOTA_DEBUG

  	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 inline struct dquot **i_dquot(struct inode *inode)
  {

  	return inode->i_sb->s_op->get_dquots(inode);
  }

  static int dqinit_needed(struct inode *inode, int type)
  {

  	struct dquot * const *dquots;

  	int cnt;
  
  	if (IS_NOQUOTA(inode))
  		return 0;

  
  	dquots = i_dquot(inode);

  	if (type != -1)

  		return !dquots[type];

  	for (cnt = 0; cnt < MAXQUOTAS; cnt++)

  		if (!dquots[cnt])

  			return 1;
  	return 0;
  }

  /* This routine is guarded by s_umount semaphore */

  static int add_dquot_ref(struct super_block *sb, int type)

  {

  	struct inode *inode, *old_inode = NULL;

  #ifdef CONFIG_QUOTA_DEBUG

  	int reserved = 0;

  #endif

  	int err = 0;

  	spin_lock(&sb->s_inode_list_lock);

  	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {

  		spin_lock(&inode->i_lock);
  		if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
  		    !atomic_read(&inode->i_writecount) ||
  		    !dqinit_needed(inode, type)) {
  			spin_unlock(&inode->i_lock);

  			continue;

  		}

  		__iget(inode);

  		spin_unlock(&inode->i_lock);

  		spin_unlock(&sb->s_inode_list_lock);

  #ifdef CONFIG_QUOTA_DEBUG
  		if (unlikely(inode_get_rsv_space(inode) > 0))
  			reserved = 1;
  #endif

  		iput(old_inode);

  		err = __dquot_initialize(inode, type);
  		if (err) {
  			iput(inode);
  			goto out;
  		}

  
  		/*
  		 * We hold a reference to 'inode' so it couldn't have been
  		 * removed from s_inodes list while we dropped the

  		 * s_inode_list_lock. We cannot iput the inode now as we can be

  		 * holding the last reference and we cannot iput it under

  		 * s_inode_list_lock. So we keep the reference and iput it

  		 * later.
  		 */

  		old_inode = inode;

  		cond_resched();

  		spin_lock(&sb->s_inode_list_lock);

  	}

  	spin_unlock(&sb->s_inode_list_lock);

  	iput(old_inode);

  out:

  #ifdef CONFIG_QUOTA_DEBUG

  	if (reserved) {

  		quota_error(sb, "Writes happened before quota was turned on "
  			"thus quota information is probably inconsistent. "
  			"Please run quotacheck(8)");

  	}

  #endif

  	return err;

  }

  /*

   * Remove references to dquots from inode and add dquot to list for freeing

   * if we have the last reference to dquot

   */

  static void remove_inode_dquot_ref(struct inode *inode, int type,
  				   struct list_head *tofree_head)

  {

  	struct dquot **dquots = i_dquot(inode);
  	struct dquot *dquot = dquots[type];

  	if (!dquot)
  		return;

  	dquots[type] = NULL;

  	if (list_empty(&dquot->dq_free)) {
  		/*
  		 * The inode still has reference to dquot so it can't be in the
  		 * free list
  		 */
  		spin_lock(&dq_list_lock);
  		list_add(&dquot->dq_free, tofree_head);
  		spin_unlock(&dq_list_lock);
  	} else {
  		/*
  		 * Dquot is already in a list to put so we won't drop the last
  		 * reference here.
  		 */
  		dqput(dquot);

  	}

  }

  /*
   * Free list of dquots
   * Dquots are removed from inodes and 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;

  	while (act_head != tofree_head) {
  		dquot = list_entry(act_head, struct dquot, dq_free);
  		act_head = act_head->next;

  		/* Remove dquot from the list so we won't have problems... */
  		list_del_init(&dquot->dq_free);

  		dqput(dquot);
  	}
  }

  static void remove_dquot_ref(struct super_block *sb, int type,
  		struct list_head *tofree_head)
  {
  	struct inode *inode;

  #ifdef CONFIG_QUOTA_DEBUG

  	int reserved = 0;

  #endif

  	spin_lock(&sb->s_inode_list_lock);

  	list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {

  		/*
  		 *  We have to scan also I_NEW inodes because they can already
  		 *  have quota pointer initialized. Luckily, we need to touch
  		 *  only quota pointers and these have separate locking

  		 *  (dq_data_lock).

  		 */

  		spin_lock(&dq_data_lock);

  		if (!IS_NOQUOTA(inode)) {

  #ifdef CONFIG_QUOTA_DEBUG

  			if (unlikely(inode_get_rsv_space(inode) > 0))
  				reserved = 1;

  #endif

  			remove_inode_dquot_ref(inode, type, tofree_head);

  		}

  		spin_unlock(&dq_data_lock);

  	}

  	spin_unlock(&sb->s_inode_list_lock);

  #ifdef CONFIG_QUOTA_DEBUG
  	if (reserved) {
  		printk(KERN_WARNING "VFS (%s): Writes happened after quota"
  			" was disabled thus quota information is probably "
  			"inconsistent. Please run quotacheck(8).
  ", sb->s_id);
  	}
  #endif

  }

  /* 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) {

  		remove_dquot_ref(sb, type, &tofree_head);

  		synchronize_srcu(&dquot_srcu);

  		put_dquot_list(&tofree_head);
  	}

  }

  static inline
  void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
  {

  	if (dquot->dq_dqb.dqb_rsvspace >= number)
  		dquot->dq_dqb.dqb_rsvspace -= number;
  	else {
  		WARN_ON_ONCE(1);
  		dquot->dq_dqb.dqb_rsvspace = 0;
  	}

  	if (dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace <=
  	    dquot->dq_dqb.dqb_bsoftlimit)
  		dquot->dq_dqb.dqb_btime = (time64_t) 0;
  	clear_bit(DQ_BLKS_B, &dquot->dq_flags);

  }

  static 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 = (time64_t) 0;

  	clear_bit(DQ_INODES_B, &dquot->dq_flags);
  }

  static 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_rsvspace <=
  	    dquot->dq_dqb.dqb_bsoftlimit)

  		dquot->dq_dqb.dqb_btime = (time64_t) 0;

  	clear_bit(DQ_BLKS_B, &dquot->dq_flags);
  }

  struct dquot_warn {
  	struct super_block *w_sb;

  	struct kqid w_dq_id;

  	short w_type;
  };

  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 int need_print_warning(struct dquot_warn *warn)

  {
  	if (!flag_print_warnings)
  		return 0;

  	switch (warn->w_dq_id.type) {

  		case USRQUOTA:

  			return uid_eq(current_fsuid(), warn->w_dq_id.uid);

  		case GRPQUOTA:

  			return in_group_p(warn->w_dq_id.gid);

  		case PRJQUOTA:
  			return 1;

  	}
  	return 0;
  }

  /* Print warning to user which exceeded quota */

  static void print_warning(struct dquot_warn *warn)

  {
  	char *msg = NULL;

  	struct tty_struct *tty;

  	int warntype = warn->w_type;

  	if (warntype == QUOTA_NL_IHARDBELOW ||
  	    warntype == QUOTA_NL_ISOFTBELOW ||
  	    warntype == QUOTA_NL_BHARDBELOW ||

  	    warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn))

  		return;

  	tty = get_current_tty();
  	if (!tty)

  		return;

  	tty_write_message(tty, warn->w_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[warn->w_dq_id.type]);

  	switch (warntype) {

  		case QUOTA_NL_IHARDWARN:

  			msg = " file limit reached.\r
  ";
  			break;

  		case QUOTA_NL_ISOFTLONGWARN:

  			msg = " file quota exceeded too long.\r
  ";
  			break;

  		case QUOTA_NL_ISOFTWARN:

  			msg = " file quota exceeded.\r
  ";
  			break;

  		case QUOTA_NL_BHARDWARN:

  			msg = " block limit reached.\r
  ";
  			break;

  		case QUOTA_NL_BSOFTLONGWARN:

  			msg = " block quota exceeded too long.\r
  ";
  			break;

  		case QUOTA_NL_BSOFTWARN:

  			msg = " block quota exceeded.\r
  ";
  			break;
  	}

  	tty_write_message(tty, msg);

  	tty_kref_put(tty);

  }

  #endif

  static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot,
  			    int warntype)
  {
  	if (warning_issued(dquot, warntype))
  		return;
  	warn->w_type = warntype;
  	warn->w_sb = dquot->dq_sb;
  	warn->w_dq_id = dquot->dq_id;

  }

  /*
   * Write warnings to the console and send warning messages over netlink.
   *

   * Note that this function can call into tty and networking code.

   */

  static void flush_warnings(struct dquot_warn *warn)

  {
  	int i;

  	for (i = 0; i < MAXQUOTAS; i++) {

  		if (warn[i].w_type == QUOTA_NL_NOWARN)
  			continue;

  #ifdef CONFIG_PRINT_QUOTA_WARNING

  		print_warning(&warn[i]);

  #endif

  		quota_send_warning(warn[i].w_dq_id,

  				   warn[i].w_sb->s_dev, warn[i].w_type);

  	}

  }

  static int ignore_hardlimit(struct dquot *dquot)

  {

  	struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type];

  
  	return capable(CAP_SYS_RESOURCE) &&

  	       (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||

  		!(info->dqi_flags & DQF_ROOT_SQUASH));

  }

  static int dquot_add_inodes(struct dquot *dquot, qsize_t inodes,
  			    struct dquot_warn *warn)

  {

  	qsize_t newinodes;
  	int ret = 0;

  	spin_lock(&dquot->dq_dqb_lock);
  	newinodes = dquot->dq_dqb.dqb_curinodes + inodes;

  	if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) ||

  	    test_bit(DQ_FAKE_B, &dquot->dq_flags))

  		goto add;

  
  	if (dquot->dq_dqb.dqb_ihardlimit &&

  	    newinodes > dquot->dq_dqb.dqb_ihardlimit &&

              !ignore_hardlimit(dquot)) {

  		prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN);

  		ret = -EDQUOT;
  		goto out;

  	}
  
  	if (dquot->dq_dqb.dqb_isoftlimit &&

  	    newinodes > dquot->dq_dqb.dqb_isoftlimit &&
  	    dquot->dq_dqb.dqb_itime &&

  	    ktime_get_real_seconds() >= dquot->dq_dqb.dqb_itime &&

              !ignore_hardlimit(dquot)) {

  		prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN);

  		ret = -EDQUOT;
  		goto out;

  	}
  
  	if (dquot->dq_dqb.dqb_isoftlimit &&

  	    newinodes > dquot->dq_dqb.dqb_isoftlimit &&

  	    dquot->dq_dqb.dqb_itime == 0) {

  		prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN);

  		dquot->dq_dqb.dqb_itime = ktime_get_real_seconds() +

  		    sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace;

  	}

  add:
  	dquot->dq_dqb.dqb_curinodes = newinodes;

  out:
  	spin_unlock(&dquot->dq_dqb_lock);
  	return ret;

  }

  static int dquot_add_space(struct dquot *dquot, qsize_t space,
  			   qsize_t rsv_space, unsigned int flags,
  			   struct dquot_warn *warn)

  {

  	qsize_t tspace;

  	struct super_block *sb = dquot->dq_sb;

  	int ret = 0;

  	spin_lock(&dquot->dq_dqb_lock);

  	if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) ||

  	    test_bit(DQ_FAKE_B, &dquot->dq_flags))

  		goto finish;

  	tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace

  		+ space + rsv_space;

  	if (dquot->dq_dqb.dqb_bhardlimit &&

  	    tspace > dquot->dq_dqb.dqb_bhardlimit &&

              !ignore_hardlimit(dquot)) {

  		if (flags & DQUOT_SPACE_WARN)

  			prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN);

  		ret = -EDQUOT;

  		goto finish;

  	}
  
  	if (dquot->dq_dqb.dqb_bsoftlimit &&

  	    tspace > dquot->dq_dqb.dqb_bsoftlimit &&

  	    dquot->dq_dqb.dqb_btime &&

  	    ktime_get_real_seconds() >= dquot->dq_dqb.dqb_btime &&

              !ignore_hardlimit(dquot)) {

  		if (flags & DQUOT_SPACE_WARN)

  			prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN);

  		ret = -EDQUOT;

  		goto finish;

  	}
  
  	if (dquot->dq_dqb.dqb_bsoftlimit &&

  	    tspace > dquot->dq_dqb.dqb_bsoftlimit &&

  	    dquot->dq_dqb.dqb_btime == 0) {

  		if (flags & DQUOT_SPACE_WARN) {

  			prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN);

  			dquot->dq_dqb.dqb_btime = ktime_get_real_seconds() +

  			    sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace;

  		} else {

  			/*
  			 * We don't allow preallocation to exceed softlimit so exceeding will
  			 * be always printed
  			 */

  			ret = -EDQUOT;

  			goto finish;

  		}

  	}

  finish:
  	/*
  	 * We have to be careful and go through warning generation & grace time
  	 * setting even if DQUOT_SPACE_NOFAIL is set. That's why we check it
  	 * only here...
  	 */
  	if (flags & DQUOT_SPACE_NOFAIL)
  		ret = 0;
  	if (!ret) {
  		dquot->dq_dqb.dqb_rsvspace += rsv_space;
  		dquot->dq_dqb.dqb_curspace += space;
  	}

  	spin_unlock(&dquot->dq_dqb_lock);
  	return ret;

  }

  static int info_idq_free(struct dquot *dquot, qsize_t inodes)

  {

  	qsize_t newinodes;

  	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_id.type))

  		return QUOTA_NL_NOWARN;

  	newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
  	if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)

  		return QUOTA_NL_ISOFTBELOW;
  	if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&

  	    newinodes < dquot->dq_dqb.dqb_ihardlimit)

  		return QUOTA_NL_IHARDBELOW;
  	return QUOTA_NL_NOWARN;
  }
  
  static int info_bdq_free(struct dquot *dquot, qsize_t space)
  {

  	qsize_t tspace;
  
  	tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace;

  	if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||

  	    tspace <= dquot->dq_dqb.dqb_bsoftlimit)

  		return QUOTA_NL_NOWARN;

  	if (tspace - space <= dquot->dq_dqb.dqb_bsoftlimit)

  		return QUOTA_NL_BSOFTBELOW;

  	if (tspace >= dquot->dq_dqb.dqb_bhardlimit &&
  	    tspace - space < dquot->dq_dqb.dqb_bhardlimit)

  		return QUOTA_NL_BHARDBELOW;
  	return QUOTA_NL_NOWARN;
  }

  static int dquot_active(const struct inode *inode)
  {
  	struct super_block *sb = inode->i_sb;
  
  	if (IS_NOQUOTA(inode))
  		return 0;
  	return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb);
  }

  /*

   * Initialize quota pointers in inode
   *

   * It is better to call this function outside of any transaction as it
   * might need a lot of space in journal for dquot structure allocation.

   */

  static int __dquot_initialize(struct inode *inode, int type)

  {

  	int cnt, init_needed = 0;

  	struct dquot **dquots, *got[MAXQUOTAS] = {};

  	struct super_block *sb = inode->i_sb;

  	qsize_t rsv;

  	int ret = 0;

  	if (!dquot_active(inode))

  		return 0;

  	dquots = i_dquot(inode);

  	/* First get references to structures we might need. */
  	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {

  		struct kqid qid;

  		kprojid_t projid;
  		int rc;

  		struct dquot *dquot;

  		if (type != -1 && cnt != type)
  			continue;

  		/*
  		 * The i_dquot should have been initialized in most cases,
  		 * we check it without locking here to avoid unnecessary
  		 * dqget()/dqput() calls.
  		 */

  		if (dquots[cnt])

  			continue;