fs/sdfat/api.h - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  *  Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
  *
  *  This program is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU General Public License
  *  as published by the Free Software Foundation; either version 2
  *  of the License, or (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */

 #ifndef _SDFAT_API_H
 #define _SDFAT_API_H

 #include "config.h"
 #include "sdfat_fs.h"

 #ifdef __cplusplus
 extern "C" {
 #endif /* __cplusplus */


 /*----------------------------------------------------------------------*/
 /*  Configure Constant & Macro Definitions                              */
 /*----------------------------------------------------------------------*/
 /* cache size (in number of sectors)                */
 /* (should be an exponential value of 2)            */
 #define FAT_CACHE_SIZE          128
 #define FAT_CACHE_HASH_SIZE     64
 #define BUF_CACHE_SIZE          256
 #define BUF_CACHE_HASH_SIZE     64

 /* Read-ahead related                                */
 /* First config vars. should be pow of 2             */
 #define FCACHE_MAX_RA_SIZE	(PAGE_SIZE)
 #define DCACHE_MAX_RA_SIZE	(128*1024)

 /*----------------------------------------------------------------------*/
 /*  Constant & Macro Definitions                                        */
 /*----------------------------------------------------------------------*/
 /* type values */
 #define TYPE_UNUSED             0x0000
 #define TYPE_DELETED            0x0001
 #define TYPE_INVALID            0x0002
 #define TYPE_CRITICAL_PRI       0x0100
 #define TYPE_BITMAP             0x0101
 #define TYPE_UPCASE             0x0102
 #define TYPE_VOLUME             0x0103
 #define TYPE_DIR                0x0104
 #define TYPE_FILE               0x011F
 #define TYPE_SYMLINK            0x015F
 #define TYPE_CRITICAL_SEC       0x0200
 #define TYPE_STREAM             0x0201
 #define TYPE_EXTEND             0x0202
 #define TYPE_ACL                0x0203
 #define TYPE_BENIGN_PRI         0x0400
 #define TYPE_GUID               0x0401
 #define TYPE_PADDING            0x0402
 #define TYPE_ACLTAB             0x0403
 #define TYPE_BENIGN_SEC         0x0800
 #define TYPE_ALL                0x0FFF

 /* eio values */
 #define SDFAT_EIO_NONE		(0x00000000)
 #define SDFAT_EIO_READ		(0x00000001)
 #define SDFAT_EIO_WRITE		(0x00000002)
 #define SDFAT_EIO_BDI		(0x00000004)

 /* modes for volume allocation unit status */
 #define VOL_AU_STAT_TOTAL	(0)
 #define VOL_AU_STAT_CLEAN	(1)
 #define VOL_AU_STAT_FULL	(2)

 /*----------------------------------------------------------------------*/
 /*  NLS Type Definitions                                                    */
 /*----------------------------------------------------------------------*/

 /* DOS name structure */
 typedef struct {
 	u8       name[DOS_NAME_LENGTH];
 	u8       name_case;
 } DOS_NAME_T;

 /* unicode name structure */
 typedef struct {
 	u16      name[MAX_NAME_LENGTH+3]; /* +3 for null and for converting */
 	u16      name_hash;
 	u8       name_len;
 } UNI_NAME_T;

 /*----------------------------------------------------------------------*/
 /*  Type Definitions                                                    */
 /*----------------------------------------------------------------------*/
 /* should be merged it to DATE_TIME_T */
 typedef union {
 	struct {
 		u8 off : 7;
 		u8 valid : 1;
 	};
 	u8 value;
 } TIMEZONE_T;

 typedef struct {
 	u16      sec;        /* 0 ~ 59               */
 	u16      min;        /* 0 ~ 59               */
 	u16      hour;       /* 0 ~ 23               */
 	u16      day;        /* 1 ~ 31               */
 	u16      mon;        /* 1 ~ 12               */
 	u16      year;       /* 0 ~ 127 (since 1980) */
 	TIMEZONE_T tz;
 } TIMESTAMP_T;

 typedef struct {
 	u16      Year;
 	u16      Month;
 	u16      Day;
 	u16      Hour;
 	u16      Minute;
 	u16      Second;
 	u16      MilliSecond;
 	TIMEZONE_T Timezone;
 } DATE_TIME_T;

 typedef struct {
 	u64      Offset;    // start sector number of the partition
 	u64      Size;      // in sectors
 } PART_INFO_T;

 typedef struct {
 	u32      SecSize;    // sector size in bytes
 	u64      DevSize;    // block device size in sectors
 } DEV_INFO_T;

 typedef struct {
 	u32      FatType;
 	u32      ClusterSize;
 	u32      NumClusters;
 	u32      FreeClusters;
 	u32      UsedClusters;
 } VOL_INFO_T;

 /* directory structure */
 typedef struct {
 	u32      dir;
 	u32      size;
 	u8       flags;
 } CHAIN_T;

 /* hint structure */
 typedef struct {
 	u32      clu;
 	union {
 		u32 off;     // cluster offset
 		s32 eidx;    // entry index
 	};
 } HINT_T;

 typedef struct {
 	spinlock_t cache_lru_lock;
 	struct list_head cache_lru;
 	s32 nr_caches;
 	u32 cache_valid_id;	// for avoiding the race between alloc and free
 } EXTENT_T;

 /* first empty entry hint information */
 typedef struct {
 	s32 eidx;		// entry index of a directory
 	s32 count;		// count of continuous empty entry
 	CHAIN_T cur;		// the cluster that first empty slot exists in
 } HINT_FEMP_T;

 /* file id structure */
 typedef struct {
 	CHAIN_T dir;
 	s32 entry;
 	u32 type;
 	u32 attr;
 	u32 start_clu;
 	u64 size;
 	u8  flags;
 	u8  reserved[3];	// padding
 	u32 version;		// the copy of low 32bit of i_version to check the validation of hint_stat
 	s64 rwoffset;		// file offset or dentry index for readdir
 	EXTENT_T extent;	// extent cache for a file
 	HINT_T	hint_bmap;	// hint for cluster last accessed
 	HINT_T	hint_stat;	// hint for entry index we try to lookup next time
 	HINT_FEMP_T hint_femp;	// hint for first empty entry
 } FILE_ID_T;

 typedef struct {
 	s8 *lfn;
 	s8 *sfn;
 	s32 lfnbuf_len;	//usally MAX_UNINAME_BUF_SIZE
 	s32 sfnbuf_len; //usally MAX_DOSNAME_BUF_SIZE, used only for vfat, not for exfat
 } DENTRY_NAMEBUF_T;

 typedef struct {
 	u32 Attr;
 	u64 Size;
 	u32 NumSubdirs;
 	DATE_TIME_T CreateTimestamp;
 	DATE_TIME_T ModifyTimestamp;
 	DATE_TIME_T AccessTimestamp;
 	DENTRY_NAMEBUF_T NameBuf;
 } DIR_ENTRY_T;

 /* cache information */
 typedef struct __cache_entry {
 	struct __cache_entry *next;
 	struct __cache_entry *prev;
 	struct {
 		struct __cache_entry *next;
 		struct __cache_entry *prev;
 	} hash;
 	u64 sec;
 	u32 flag;
 	struct buffer_head   *bh;
 } cache_ent_t;

 /*----------------------------------------------------------------------*/
 /*  Type Definitions : Wrapper & In-Core                                */
 /*----------------------------------------------------------------------*/
 typedef struct __FATENT_OPS_T {
 	s32 (*ent_get)(struct super_block *sb, u32 loc, u32 *content);
 	s32 (*ent_set)(struct super_block *sb, u32 loc, u32 content);
 } FATENT_OPS_T;

 typedef struct {
 	s32      (*alloc_cluster)(struct super_block *, u32, CHAIN_T *, s32);
 	s32      (*free_cluster)(struct super_block *, CHAIN_T *, s32);
 	s32      (*count_used_clusters)(struct super_block *, u32 *);
 	s32      (*init_dir_entry)(struct super_block *, CHAIN_T *, s32, u32, u32, u64);
 	s32      (*init_ext_entry)(struct super_block *, CHAIN_T *, s32, s32, UNI_NAME_T *, DOS_NAME_T *);
 	s32      (*find_dir_entry)(struct super_block *, FILE_ID_T *, CHAIN_T *, UNI_NAME_T *, s32, DOS_NAME_T *, u32);
 	s32      (*delete_dir_entry)(struct super_block *, CHAIN_T *, s32, s32, s32);
 	void     (*get_uniname_from_ext_entry)(struct super_block *, CHAIN_T *, s32, u16 *);
 	s32      (*count_ext_entries)(struct super_block *, CHAIN_T *, s32, DENTRY_T *);
 	s32      (*calc_num_entries)(UNI_NAME_T *);
 	s32      (*check_max_dentries)(FILE_ID_T *);
 	u32      (*get_entry_type)(DENTRY_T *);
 	void     (*set_entry_type)(DENTRY_T *, u32);
 	u32      (*get_entry_attr)(DENTRY_T *);
 	void     (*set_entry_attr)(DENTRY_T *, u32);
 	u8       (*get_entry_flag)(DENTRY_T *);
 	void     (*set_entry_flag)(DENTRY_T *, u8);
 	u32      (*get_entry_clu0)(DENTRY_T *);
 	void     (*set_entry_clu0)(DENTRY_T *, u32);
 	u64      (*get_entry_size)(DENTRY_T *);
 	void     (*set_entry_size)(DENTRY_T *, u64);
 	void     (*get_entry_time)(DENTRY_T *, TIMESTAMP_T *, u8);
 	void     (*set_entry_time)(DENTRY_T *, TIMESTAMP_T *, u8);
 	u32      (*get_au_stat)(struct super_block *, s32);
 } FS_FUNC_T;

 typedef struct __FS_INFO_T {
 	s32	 bd_opened;              // opened or not
 	u32      vol_type;               // volume FAT type
 	u32      vol_id;                 // volume serial number
 	u64      num_sectors;            // num of sectors in volume
 	u32      num_clusters;           // num of clusters in volume
 	u32      cluster_size;           // cluster size in bytes
 	u32      cluster_size_bits;
 	u32      sect_per_clus;        // cluster size in sectors
 	u32      sect_per_clus_bits;
 	u64      FAT1_start_sector;      // FAT1 start sector
 	u64      FAT2_start_sector;      // FAT2 start sector
 	u64      root_start_sector;      // root dir start sector
 	u64      data_start_sector;      // data area start sector
 	u32      num_FAT_sectors;        // num of FAT sectors
 	u32      root_dir;               // root dir cluster
 	u32      dentries_in_root;       // num of dentries in root dir
 	u32      dentries_per_clu;       // num of dentries per cluster
 	u32      vol_flag;               // volume dirty flag
 	struct buffer_head *pbr_bh;      // buffer_head of PBR sector

 	u32      map_clu;                // allocation bitmap start cluster
 	u32      map_sectors;            // num of allocation bitmap sectors
 	struct buffer_head **vol_amap;      // allocation bitmap

 	u16      **vol_utbl;               // upcase table

 	u32      clu_srch_ptr;           // cluster search pointer
 	u32      used_clusters;          // number of used clusters

 	u32      prev_eio;            // block device operation error flag

 	FS_FUNC_T   *fs_func;
 	FATENT_OPS_T   *fatent_ops;

 	s32       reserved_clusters;  // # of reserved clusters (DA)
 	void        *amap;                  // AU Allocation Map

 	/* fat cache */
 	struct {
 		cache_ent_t pool[FAT_CACHE_SIZE];
 		cache_ent_t lru_list;
 		cache_ent_t hash_list[FAT_CACHE_HASH_SIZE];
 	} fcache;

 	/* meta cache */
 	struct {
 		cache_ent_t pool[BUF_CACHE_SIZE];
 		cache_ent_t lru_list;
 		cache_ent_t keep_list;        // CACHEs in this list will not be kicked by normal lru operations
 		cache_ent_t hash_list[BUF_CACHE_HASH_SIZE];
 	} dcache;
 } FS_INFO_T;

 /*======================================================================*/
 /*                                                                      */
 /*                     API FUNCTION DECLARATIONS                        */
 /*                  (CHANGE THIS PART IF REQUIRED)                      */
 /*                                                                      */
 /*======================================================================*/

 /*----------------------------------------------------------------------*/
 /*  External Function Declarations                                      */
 /*----------------------------------------------------------------------*/

 /* file system initialization & shutdown functions */
 s32 fsapi_init(void);
 s32 fsapi_shutdown(void);

 /* volume management functions */
 s32 fsapi_mount(struct super_block *sb);
 s32 fsapi_umount(struct super_block *sb);
 s32 fsapi_statfs(struct super_block *sb, VOL_INFO_T *info);
 s32 fsapi_sync_fs(struct super_block *sb, s32 do_sync);
 s32 fsapi_set_vol_flags(struct super_block *sb, u16 new_flag, s32 always_sync);

 /* file management functions */
 s32 fsapi_lookup(struct inode *inode, u8 *path, FILE_ID_T *fid);
 s32 fsapi_create(struct inode *inode, u8 *path, u8 mode, FILE_ID_T *fid);
 s32 fsapi_read_link(struct inode *inode, FILE_ID_T *fid, void *buffer, u64 count, u64 *rcount);
 s32 fsapi_write_link(struct inode *inode, FILE_ID_T *fid, void *buffer, u64 count, u64 *wcount);
 s32 fsapi_remove(struct inode *inode, FILE_ID_T *fid); /* unlink and truncate */
 s32 fsapi_truncate(struct inode *inode, u64 old_size, u64 new_size);
 s32 fsapi_rename(struct inode *old_parent_inode, FILE_ID_T *fid,
 		struct inode *new_parent_inode, struct dentry *new_dentry);
 s32 fsapi_unlink(struct inode *inode, FILE_ID_T *fid);
 s32 fsapi_read_inode(struct inode *inode, DIR_ENTRY_T *info);
 s32 fsapi_write_inode(struct inode *inode, DIR_ENTRY_T *info, int sync);
 s32 fsapi_map_clus(struct inode *inode, u32 clu_offset, u32 *clu, int dest);
 s32 fsapi_reserve_clus(struct inode *inode);

 /* directory management functions */
 s32 fsapi_mkdir(struct inode *inode, u8 *path, FILE_ID_T *fid);
 s32 fsapi_readdir(struct inode *inode, DIR_ENTRY_T *dir_entry);
 s32 fsapi_rmdir(struct inode *inode, FILE_ID_T *fid);

 /* FAT & buf cache functions */
 s32 fsapi_cache_flush(struct super_block *sb, int do_sync);
 s32 fsapi_cache_release(struct super_block *sb);

 /* extra info functions */
 u32 fsapi_get_au_stat(struct super_block *sb, s32 mode);

 /* extent cache functions */
 void fsapi_invalidate_extent(struct inode *inode);

 /* bdev management */
 s32 fsapi_check_bdi_valid(struct super_block *sb);

 #ifdef CONFIG_SDFAT_DFR
 /*----------------------------------------------------------------------*/
 /*  Defragmentation related                                             */
 /*----------------------------------------------------------------------*/

 s32 fsapi_dfr_get_info(struct super_block *sb, void *arg);

 s32 fsapi_dfr_scan_dir(struct super_block *sb, void *args);

 s32 fsapi_dfr_validate_clus(struct inode *inode, void *chunk, int skip_prev);
 s32 fsapi_dfr_reserve_clus(struct super_block *sb, s32 nr_clus);
 s32 fsapi_dfr_mark_ignore(struct super_block *sb, unsigned int clus);
 void fsapi_dfr_unmark_ignore_all(struct super_block *sb);

 s32 fsapi_dfr_map_clus(struct inode *inode, u32 clu_offset, u32 *clu);
 void fsapi_dfr_writepage_endio(struct page *page);

 void fsapi_dfr_update_fat_prev(struct super_block *sb, int force);
 void fsapi_dfr_update_fat_next(struct super_block *sb);
 void fsapi_dfr_check_discard(struct super_block *sb);
 void fsapi_dfr_free_clus(struct super_block *sb, u32 clus);

 s32 fsapi_dfr_check_dfr_required(struct super_block *sb, int *totalau, int *cleanau, int *fullau);
 s32 fsapi_dfr_check_dfr_on(struct inode *inode, loff_t start, loff_t end, s32 cancel, const char *caller);


 #ifdef CONFIG_SDFAT_DFR_DEBUG
 void fsapi_dfr_spo_test(struct super_block *sb, int flag, const char *caller);
 #endif	/* CONFIG_SDFAT_DFR_DEBUG */

 #endif	/* CONFIG_SDFAT_DFR */


 #ifdef __cplusplus
 }
 #endif /* __cplusplus */

 #endif /* _SDFAT_API_H */

 /* end of api.h */
	/*
	* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version 2
	* of the License, or (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, see <http://www.gnu.org/licenses/>.
	*/

	#ifndef _SDFAT_API_H
	#define _SDFAT_API_H

	#include "config.h"
	#include "sdfat_fs.h"

	#ifdef __cplusplus
	extern "C" {
	#endif /* __cplusplus */


	/----------------------------------------------------------------------/
	/* Configure Constant & Macro Definitions */
	/----------------------------------------------------------------------/
	/* cache size (in number of sectors) */
	/* (should be an exponential value of 2) */
	#define FAT_CACHE_SIZE 128
	#define FAT_CACHE_HASH_SIZE 64
	#define BUF_CACHE_SIZE 256
	#define BUF_CACHE_HASH_SIZE 64

	/* Read-ahead related */
	/* First config vars. should be pow of 2 */
	#define FCACHE_MAX_RA_SIZE (PAGE_SIZE)
	#define DCACHE_MAX_RA_SIZE (128*1024)

	/----------------------------------------------------------------------/
	/* Constant & Macro Definitions */
	/----------------------------------------------------------------------/
	/* type values */
	#define TYPE_UNUSED 0x0000
	#define TYPE_DELETED 0x0001
	#define TYPE_INVALID 0x0002
	#define TYPE_CRITICAL_PRI 0x0100
	#define TYPE_BITMAP 0x0101
	#define TYPE_UPCASE 0x0102
	#define TYPE_VOLUME 0x0103
	#define TYPE_DIR 0x0104
	#define TYPE_FILE 0x011F
	#define TYPE_SYMLINK 0x015F
	#define TYPE_CRITICAL_SEC 0x0200
	#define TYPE_STREAM 0x0201
	#define TYPE_EXTEND 0x0202
	#define TYPE_ACL 0x0203
	#define TYPE_BENIGN_PRI 0x0400
	#define TYPE_GUID 0x0401
	#define TYPE_PADDING 0x0402
	#define TYPE_ACLTAB 0x0403
	#define TYPE_BENIGN_SEC 0x0800
	#define TYPE_ALL 0x0FFF

	/* eio values */
	#define SDFAT_EIO_NONE (0x00000000)
	#define SDFAT_EIO_READ (0x00000001)
	#define SDFAT_EIO_WRITE (0x00000002)
	#define SDFAT_EIO_BDI (0x00000004)

	/* modes for volume allocation unit status */
	#define VOL_AU_STAT_TOTAL (0)
	#define VOL_AU_STAT_CLEAN (1)
	#define VOL_AU_STAT_FULL (2)

	/----------------------------------------------------------------------/
	/* NLS Type Definitions */
	/----------------------------------------------------------------------/

	/* DOS name structure */
	typedef struct {
	u8 name[DOS_NAME_LENGTH];
	u8 name_case;
	} DOS_NAME_T;

	/* unicode name structure */
	typedef struct {
	u16 name[MAX_NAME_LENGTH+3]; /* +3 for null and for converting */
	u16 name_hash;
	u8 name_len;
	} UNI_NAME_T;

	/----------------------------------------------------------------------/
	/* Type Definitions */
	/----------------------------------------------------------------------/
	/* should be merged it to DATE_TIME_T */
	typedef union {
	struct {
	u8 off : 7;
	u8 valid : 1;
	};
	u8 value;
	} TIMEZONE_T;

	typedef struct {
	u16 sec; /* 0 ~ 59 */
	u16 min; /* 0 ~ 59 */
	u16 hour; /* 0 ~ 23 */
	u16 day; /* 1 ~ 31 */
	u16 mon; /* 1 ~ 12 */
	u16 year; /* 0 ~ 127 (since 1980) */
	TIMEZONE_T tz;
	} TIMESTAMP_T;

	typedef struct {
	u16 Year;
	u16 Month;
	u16 Day;
	u16 Hour;
	u16 Minute;
	u16 Second;
	u16 MilliSecond;
	TIMEZONE_T Timezone;
	} DATE_TIME_T;

	typedef struct {
	u64 Offset; // start sector number of the partition
	u64 Size; // in sectors
	} PART_INFO_T;

	typedef struct {
	u32 SecSize; // sector size in bytes
	u64 DevSize; // block device size in sectors
	} DEV_INFO_T;

	typedef struct {
	u32 FatType;
	u32 ClusterSize;
	u32 NumClusters;
	u32 FreeClusters;
	u32 UsedClusters;
	} VOL_INFO_T;

	/* directory structure */
	typedef struct {
	u32 dir;
	u32 size;
	u8 flags;
	} CHAIN_T;

	/* hint structure */
	typedef struct {
	u32 clu;
	union {
	u32 off; // cluster offset
	s32 eidx; // entry index
	};
	} HINT_T;

	typedef struct {
	spinlock_t cache_lru_lock;
	struct list_head cache_lru;
	s32 nr_caches;
	u32 cache_valid_id; // for avoiding the race between alloc and free
	} EXTENT_T;

	/* first empty entry hint information */
	typedef struct {
	s32 eidx; // entry index of a directory
	s32 count; // count of continuous empty entry
	CHAIN_T cur; // the cluster that first empty slot exists in
	} HINT_FEMP_T;

	/* file id structure */
	typedef struct {
	CHAIN_T dir;
	s32 entry;
	u32 type;
	u32 attr;
	u32 start_clu;
	u64 size;
	u8 flags;
	u8 reserved[3]; // padding
	u32 version; // the copy of low 32bit of i_version to check the validation of hint_stat
	s64 rwoffset; // file offset or dentry index for readdir
	EXTENT_T extent; // extent cache for a file
	HINT_T hint_bmap; // hint for cluster last accessed
	HINT_T hint_stat; // hint for entry index we try to lookup next time
	HINT_FEMP_T hint_femp; // hint for first empty entry
	} FILE_ID_T;

	typedef struct {
	s8 *lfn;
	s8 *sfn;
	s32 lfnbuf_len; //usally MAX_UNINAME_BUF_SIZE
	s32 sfnbuf_len; //usally MAX_DOSNAME_BUF_SIZE, used only for vfat, not for exfat
	} DENTRY_NAMEBUF_T;

	typedef struct {
	u32 Attr;
	u64 Size;
	u32 NumSubdirs;
	DATE_TIME_T CreateTimestamp;
	DATE_TIME_T ModifyTimestamp;
	DATE_TIME_T AccessTimestamp;
	DENTRY_NAMEBUF_T NameBuf;
	} DIR_ENTRY_T;

	/* cache information */
	typedef struct __cache_entry {
	struct __cache_entry *next;
	struct __cache_entry *prev;
	struct {
	struct __cache_entry *next;
	struct __cache_entry *prev;
	} hash;
	u64 sec;
	u32 flag;
	struct buffer_head *bh;
	} cache_ent_t;

	/----------------------------------------------------------------------/
	/* Type Definitions : Wrapper & In-Core */
	/----------------------------------------------------------------------/
	typedef struct __FATENT_OPS_T {
	s32 (ent_get)(struct super_block sb, u32 loc, u32 *content);
	s32 (ent_set)(struct super_block sb, u32 loc, u32 content);
	} FATENT_OPS_T;

	typedef struct {
	s32 (alloc_cluster)(struct super_block , u32, CHAIN_T *, s32);
	s32 (free_cluster)(struct super_block , CHAIN_T *, s32);
	s32 (count_used_clusters)(struct super_block , u32 *);
	s32 (init_dir_entry)(struct super_block , CHAIN_T *, s32, u32, u32, u64);
	s32 (init_ext_entry)(struct super_block , CHAIN_T , s32, s32, UNI_NAME_T , DOS_NAME_T *);
	s32 (find_dir_entry)(struct super_block , FILE_ID_T , CHAIN_T , UNI_NAME_T , s32, DOS_NAME_T , u32);
	s32 (delete_dir_entry)(struct super_block , CHAIN_T *, s32, s32, s32);
	void (get_uniname_from_ext_entry)(struct super_block , CHAIN_T , s32, u16 );
	s32 (count_ext_entries)(struct super_block , CHAIN_T , s32, DENTRY_T );
	s32 (calc_num_entries)(UNI_NAME_T );
	s32 (check_max_dentries)(FILE_ID_T );
	u32 (get_entry_type)(DENTRY_T );
	void (set_entry_type)(DENTRY_T , u32);
	u32 (get_entry_attr)(DENTRY_T );
	void (set_entry_attr)(DENTRY_T , u32);
	u8 (get_entry_flag)(DENTRY_T );
	void (set_entry_flag)(DENTRY_T , u8);
	u32 (get_entry_clu0)(DENTRY_T );
	void (set_entry_clu0)(DENTRY_T , u32);
	u64 (get_entry_size)(DENTRY_T );
	void (set_entry_size)(DENTRY_T , u64);
	void (get_entry_time)(DENTRY_T , TIMESTAMP_T *, u8);
	void (set_entry_time)(DENTRY_T , TIMESTAMP_T *, u8);
	u32 (get_au_stat)(struct super_block , s32);
	} FS_FUNC_T;

	typedef struct __FS_INFO_T {
	s32 bd_opened; // opened or not
	u32 vol_type; // volume FAT type
	u32 vol_id; // volume serial number
	u64 num_sectors; // num of sectors in volume
	u32 num_clusters; // num of clusters in volume
	u32 cluster_size; // cluster size in bytes
	u32 cluster_size_bits;
	u32 sect_per_clus; // cluster size in sectors
	u32 sect_per_clus_bits;
	u64 FAT1_start_sector; // FAT1 start sector
	u64 FAT2_start_sector; // FAT2 start sector
	u64 root_start_sector; // root dir start sector
	u64 data_start_sector; // data area start sector
	u32 num_FAT_sectors; // num of FAT sectors
	u32 root_dir; // root dir cluster
	u32 dentries_in_root; // num of dentries in root dir
	u32 dentries_per_clu; // num of dentries per cluster
	u32 vol_flag; // volume dirty flag
	struct buffer_head *pbr_bh; // buffer_head of PBR sector

	u32 map_clu; // allocation bitmap start cluster
	u32 map_sectors; // num of allocation bitmap sectors
	struct buffer_head **vol_amap; // allocation bitmap

	u16 **vol_utbl; // upcase table

	u32 clu_srch_ptr; // cluster search pointer
	u32 used_clusters; // number of used clusters

	u32 prev_eio; // block device operation error flag

	FS_FUNC_T *fs_func;
	FATENT_OPS_T *fatent_ops;

	s32 reserved_clusters; // # of reserved clusters (DA)
	void *amap; // AU Allocation Map

	/* fat cache */
	struct {
	cache_ent_t pool[FAT_CACHE_SIZE];
	cache_ent_t lru_list;
	cache_ent_t hash_list[FAT_CACHE_HASH_SIZE];
	} fcache;

	/* meta cache */
	struct {
	cache_ent_t pool[BUF_CACHE_SIZE];
	cache_ent_t lru_list;
	cache_ent_t keep_list; // CACHEs in this list will not be kicked by normal lru operations
	cache_ent_t hash_list[BUF_CACHE_HASH_SIZE];
	} dcache;
	} FS_INFO_T;

	/======================================================================/
	/* */
	/* API FUNCTION DECLARATIONS */
	/* (CHANGE THIS PART IF REQUIRED) */
	/* */
	/======================================================================/

	/----------------------------------------------------------------------/
	/* External Function Declarations */
	/----------------------------------------------------------------------/

	/* file system initialization & shutdown functions */
	s32 fsapi_init(void);
	s32 fsapi_shutdown(void);

	/* volume management functions */
	s32 fsapi_mount(struct super_block *sb);
	s32 fsapi_umount(struct super_block *sb);
	s32 fsapi_statfs(struct super_block sb, VOL_INFO_T info);
	s32 fsapi_sync_fs(struct super_block *sb, s32 do_sync);
	s32 fsapi_set_vol_flags(struct super_block *sb, u16 new_flag, s32 always_sync);

	/* file management functions */
	s32 fsapi_lookup(struct inode inode, u8 path, FILE_ID_T *fid);
	s32 fsapi_create(struct inode inode, u8 path, u8 mode, FILE_ID_T *fid);
	s32 fsapi_read_link(struct inode inode, FILE_ID_T fid, void buffer, u64 count, u64 rcount);
	s32 fsapi_write_link(struct inode inode, FILE_ID_T fid, void buffer, u64 count, u64 wcount);
	s32 fsapi_remove(struct inode inode, FILE_ID_T fid); /* unlink and truncate */
	s32 fsapi_truncate(struct inode *inode, u64 old_size, u64 new_size);
	s32 fsapi_rename(struct inode old_parent_inode, FILE_ID_T fid,
	struct inode new_parent_inode, struct dentry new_dentry);
	s32 fsapi_unlink(struct inode inode, FILE_ID_T fid);
	s32 fsapi_read_inode(struct inode inode, DIR_ENTRY_T info);
	s32 fsapi_write_inode(struct inode inode, DIR_ENTRY_T info, int sync);
	s32 fsapi_map_clus(struct inode inode, u32 clu_offset, u32 clu, int dest);
	s32 fsapi_reserve_clus(struct inode *inode);

	/* directory management functions */
	s32 fsapi_mkdir(struct inode inode, u8 path, FILE_ID_T *fid);
	s32 fsapi_readdir(struct inode inode, DIR_ENTRY_T dir_entry);
	s32 fsapi_rmdir(struct inode inode, FILE_ID_T fid);

	/* FAT & buf cache functions */
	s32 fsapi_cache_flush(struct super_block *sb, int do_sync);
	s32 fsapi_cache_release(struct super_block *sb);

	/* extra info functions */
	u32 fsapi_get_au_stat(struct super_block *sb, s32 mode);

	/* extent cache functions */
	void fsapi_invalidate_extent(struct inode *inode);

	/* bdev management */
	s32 fsapi_check_bdi_valid(struct super_block *sb);

	#ifdef CONFIG_SDFAT_DFR
	/----------------------------------------------------------------------/
	/* Defragmentation related */
	/----------------------------------------------------------------------/

	s32 fsapi_dfr_get_info(struct super_block sb, void arg);

	s32 fsapi_dfr_scan_dir(struct super_block sb, void args);

	s32 fsapi_dfr_validate_clus(struct inode inode, void chunk, int skip_prev);
	s32 fsapi_dfr_reserve_clus(struct super_block *sb, s32 nr_clus);
	s32 fsapi_dfr_mark_ignore(struct super_block *sb, unsigned int clus);
	void fsapi_dfr_unmark_ignore_all(struct super_block *sb);

	s32 fsapi_dfr_map_clus(struct inode inode, u32 clu_offset, u32 clu);
	void fsapi_dfr_writepage_endio(struct page *page);

	void fsapi_dfr_update_fat_prev(struct super_block *sb, int force);
	void fsapi_dfr_update_fat_next(struct super_block *sb);
	void fsapi_dfr_check_discard(struct super_block *sb);
	void fsapi_dfr_free_clus(struct super_block *sb, u32 clus);

	s32 fsapi_dfr_check_dfr_required(struct super_block sb, int totalau, int cleanau, int fullau);
	s32 fsapi_dfr_check_dfr_on(struct inode inode, loff_t start, loff_t end, s32 cancel, const char caller);


	#ifdef CONFIG_SDFAT_DFR_DEBUG
	void fsapi_dfr_spo_test(struct super_block sb, int flag, const char caller);
	#endif /* CONFIG_SDFAT_DFR_DEBUG */

	#endif /* CONFIG_SDFAT_DFR */


	#ifdef __cplusplus
	}
	#endif /* __cplusplus */

	#endif /* _SDFAT_API_H */

	/* end of api.h */