linux/fs/quota/quota_tree.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *	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(…) …;
MODULE_DESCRIPTION(…) …;
MODULE_LICENSE(…) …;

/*
 * Maximum quota tree depth we support. Only to limit recursion when working
 * with the tree.
 */
#define MAX_QTREE_DEPTH …

#define __QUOTA_QT_PARANOIA

static int __get_index(struct qtree_mem_dqinfo *info, qid_t id, int depth)
{ … }

static int get_index(struct qtree_mem_dqinfo *info, struct kqid qid, int depth)
{ … }

/* Number of entries in one blocks */
static int qtree_dqstr_in_blk(struct qtree_mem_dqinfo *info)
{ … }

static ssize_t read_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf)
{ … }

static ssize_t write_blk(struct qtree_mem_dqinfo *info, uint blk, char *buf)
{ … }

static inline int do_check_range(struct super_block *sb, const char *val_name,
				 uint val, uint min_val, uint max_val)
{ … }

static int check_dquot_block_header(struct qtree_mem_dqinfo *info,
				    struct qt_disk_dqdbheader *dh)
{ … }

/* Remove empty block from list and return it */
static int get_free_dqblk(struct qtree_mem_dqinfo *info)
{ … }

/* Insert empty block to the list */
static int put_free_dqblk(struct qtree_mem_dqinfo *info, char *buf, uint blk)
{ … }

/* Remove given block from the list of blocks with free entries */
static int remove_free_dqentry(struct qtree_mem_dqinfo *info, char *buf,
			       uint blk)
{ … }

/* Insert given block to the beginning of list with free entries */
static int insert_free_dqentry(struct qtree_mem_dqinfo *info, char *buf,
			       uint blk)
{ … }

/* Is the entry in the block free? */
int qtree_entry_unused(struct qtree_mem_dqinfo *info, char *disk)
{ … }
EXPORT_SYMBOL(…);

/* Find space for dquot */
static uint find_free_dqentry(struct qtree_mem_dqinfo *info,
			      struct dquot *dquot, int *err)
{ … }

/* Insert reference to structure into the trie */
static int do_insert_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
			  uint *blks, int depth)
{ … }

/* Wrapper for inserting quota structure into tree */
static inline int dq_insert_tree(struct qtree_mem_dqinfo *info,
				 struct dquot *dquot)
{ … }

/*
 * 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)
{ … }
EXPORT_SYMBOL(…);

/* Free dquot entry in data block */
static int free_dqentry(struct qtree_mem_dqinfo *info, struct dquot *dquot,
			uint blk)
{ … }

/* Remove reference to dquot from tree */
static int remove_tree(struct qtree_mem_dqinfo *info, struct dquot *dquot,
		       uint *blks, int depth)
{ … }

/* Delete dquot from tree */
int qtree_delete_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
{ … }
EXPORT_SYMBOL(…);

/* Find entry in block */
static loff_t find_block_dqentry(struct qtree_mem_dqinfo *info,
				 struct dquot *dquot, uint blk)
{ … }

/* Find entry for given id in the tree */
static loff_t find_tree_dqentry(struct qtree_mem_dqinfo *info,
				struct dquot *dquot, uint *blks, int depth)
{ … }

/* Find entry for given id in the tree - wrapper function */
static inline loff_t find_dqentry(struct qtree_mem_dqinfo *info,
				  struct dquot *dquot)
{ … }

int qtree_read_dquot(struct qtree_mem_dqinfo *info, struct dquot *dquot)
{ … }
EXPORT_SYMBOL(…);

/* 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)
{ … }
EXPORT_SYMBOL(…);

static int find_next_id(struct qtree_mem_dqinfo *info, qid_t *id,
			unsigned int blk, int depth)
{ … }

int qtree_get_next_id(struct qtree_mem_dqinfo *info, struct kqid *qid)
{ … }
EXPORT_SYMBOL(…);