linux/fs/exfat/exfat_fs.h
Hyeongseok Kim c6e2f52e30 exfat: speed up iterate/lookup by fixing start point of traversing cluster chain
When directory iterate and lookup is called, there's a buggy rewinding
of start point for traversing cluster chain to the parent directory
entry's first cluster. This caused repeated cluster chain traversing
from the first entry of the parent directory that would show worse
performance if huge amounts of files exist under the parent directory.
Fix not to rewind, make continue from currently referenced cluster and
dir entry.

Tested with 50,000 files under single directory / 256GB sdcard,
with command "time ls -l > /dev/null",
Before :     0m08.69s real     0m00.27s user     0m05.91s system
After  :     0m07.01s real     0m00.25s user     0m04.34s system

Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
Reviewed-by: Sungjong Seo <sj1557.seo@samsung.com>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
2021-04-27 20:45:07 +09:00

530 lines
17 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
*/
#ifndef _EXFAT_FS_H
#define _EXFAT_FS_H
#include <linux/fs.h>
#include <linux/ratelimit.h>
#include <linux/nls.h>
#define EXFAT_SUPER_MAGIC 0x2011BAB0UL
#define EXFAT_ROOT_INO 1
#define EXFAT_CLUSTERS_UNTRACKED (~0u)
/*
* exfat error flags
*/
enum exfat_error_mode {
EXFAT_ERRORS_CONT, /* ignore error and continue */
EXFAT_ERRORS_PANIC, /* panic on error */
EXFAT_ERRORS_RO, /* remount r/o on error */
};
/*
* exfat nls lossy flag
*/
enum {
NLS_NAME_NO_LOSSY, /* no lossy */
NLS_NAME_LOSSY, /* just detected incorrect filename(s) */
NLS_NAME_OVERLEN, /* the length is over than its limit */
};
#define EXFAT_HASH_BITS 8
#define EXFAT_HASH_SIZE (1UL << EXFAT_HASH_BITS)
/*
* Type Definitions
*/
#define ES_2_ENTRIES 2
#define ES_ALL_ENTRIES 0
#define DIR_DELETED 0xFFFF0321
/* 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_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
#define MAX_CHARSET_SIZE 6 /* max size of multi-byte character */
#define MAX_NAME_LENGTH 255 /* max len of file name excluding NULL */
#define MAX_VFSNAME_BUF_SIZE ((MAX_NAME_LENGTH + 1) * MAX_CHARSET_SIZE)
/* Enough size to hold 256 dentry (even 512 Byte sector) */
#define DIR_CACHE_SIZE (256*sizeof(struct exfat_dentry)/512+1)
#define EXFAT_HINT_NONE -1
#define EXFAT_MIN_SUBDIR 2
/*
* helpers for cluster size to byte conversion.
*/
#define EXFAT_CLU_TO_B(b, sbi) ((b) << (sbi)->cluster_size_bits)
#define EXFAT_B_TO_CLU(b, sbi) ((b) >> (sbi)->cluster_size_bits)
#define EXFAT_B_TO_CLU_ROUND_UP(b, sbi) \
(((b - 1) >> (sbi)->cluster_size_bits) + 1)
#define EXFAT_CLU_OFFSET(off, sbi) ((off) & ((sbi)->cluster_size - 1))
/*
* helpers for block size to byte conversion.
*/
#define EXFAT_BLK_TO_B(b, sb) ((b) << (sb)->s_blocksize_bits)
#define EXFAT_B_TO_BLK(b, sb) ((b) >> (sb)->s_blocksize_bits)
#define EXFAT_B_TO_BLK_ROUND_UP(b, sb) \
(((b - 1) >> (sb)->s_blocksize_bits) + 1)
#define EXFAT_BLK_OFFSET(off, sb) ((off) & ((sb)->s_blocksize - 1))
/*
* helpers for block size to dentry size conversion.
*/
#define EXFAT_B_TO_DEN_IDX(b, sbi) \
((b) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS))
#define EXFAT_B_TO_DEN(b) ((b) >> DENTRY_SIZE_BITS)
#define EXFAT_DEN_TO_B(b) ((b) << DENTRY_SIZE_BITS)
/*
* helpers for fat entry.
*/
#define FAT_ENT_SIZE (4)
#define FAT_ENT_SIZE_BITS (2)
#define FAT_ENT_OFFSET_SECTOR(sb, loc) (EXFAT_SB(sb)->FAT1_start_sector + \
(((u64)loc << FAT_ENT_SIZE_BITS) >> sb->s_blocksize_bits))
#define FAT_ENT_OFFSET_BYTE_IN_SECTOR(sb, loc) \
((loc << FAT_ENT_SIZE_BITS) & (sb->s_blocksize - 1))
/*
* helpers for bitmap.
*/
#define CLUSTER_TO_BITMAP_ENT(clu) ((clu) - EXFAT_RESERVED_CLUSTERS)
#define BITMAP_ENT_TO_CLUSTER(ent) ((ent) + EXFAT_RESERVED_CLUSTERS)
#define BITS_PER_SECTOR(sb) ((sb)->s_blocksize * BITS_PER_BYTE)
#define BITS_PER_SECTOR_MASK(sb) (BITS_PER_SECTOR(sb) - 1)
#define BITMAP_OFFSET_SECTOR_INDEX(sb, ent) \
((ent / BITS_PER_BYTE) >> (sb)->s_blocksize_bits)
#define BITMAP_OFFSET_BIT_IN_SECTOR(sb, ent) (ent & BITS_PER_SECTOR_MASK(sb))
#define BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent) \
((ent / BITS_PER_BYTE) & ((sb)->s_blocksize - 1))
#define BITS_PER_BYTE_MASK 0x7
#define IGNORED_BITS_REMAINED(clu, clu_base) ((1 << ((clu) - (clu_base))) - 1)
struct exfat_dentry_namebuf {
char *lfn;
int lfnbuf_len; /* usually MAX_UNINAME_BUF_SIZE */
};
/* unicode name structure */
struct exfat_uni_name {
/* +3 for null and for converting */
unsigned short name[MAX_NAME_LENGTH + 3];
u16 name_hash;
unsigned char name_len;
};
/* directory structure */
struct exfat_chain {
unsigned int dir;
unsigned int size;
unsigned char flags;
};
/* first empty entry hint information */
struct exfat_hint_femp {
/* entry index of a directory */
int eidx;
/* count of continuous empty entry */
int count;
/* the cluster that first empty slot exists in */
struct exfat_chain cur;
};
/* hint structure */
struct exfat_hint {
unsigned int clu;
union {
unsigned int off; /* cluster offset */
int eidx; /* entry index */
};
};
struct exfat_entry_set_cache {
struct super_block *sb;
bool modified;
unsigned int start_off;
int num_bh;
struct buffer_head *bh[DIR_CACHE_SIZE];
unsigned int num_entries;
};
struct exfat_dir_entry {
struct exfat_chain dir;
int entry;
unsigned int type;
unsigned int start_clu;
unsigned char flags;
unsigned short attr;
loff_t size;
unsigned int num_subdirs;
struct timespec64 atime;
struct timespec64 mtime;
struct timespec64 crtime;
struct exfat_dentry_namebuf namebuf;
};
/*
* exfat mount in-memory data
*/
struct exfat_mount_options {
kuid_t fs_uid;
kgid_t fs_gid;
unsigned short fs_fmask;
unsigned short fs_dmask;
/* permission for setting the [am]time */
unsigned short allow_utime;
/* charset for filename input/display */
char *iocharset;
/* on error: continue, panic, remount-ro */
enum exfat_error_mode errors;
unsigned utf8:1, /* Use of UTF-8 character set */
discard:1; /* Issue discard requests on deletions */
int time_offset; /* Offset of timestamps from UTC (in minutes) */
};
/*
* EXFAT file system superblock in-memory data
*/
struct exfat_sb_info {
unsigned long long num_sectors; /* num of sectors in volume */
unsigned int num_clusters; /* num of clusters in volume */
unsigned int cluster_size; /* cluster size in bytes */
unsigned int cluster_size_bits;
unsigned int sect_per_clus; /* cluster size in sectors */
unsigned int sect_per_clus_bits;
unsigned long long FAT1_start_sector; /* FAT1 start sector */
unsigned long long FAT2_start_sector; /* FAT2 start sector */
unsigned long long data_start_sector; /* data area start sector */
unsigned int num_FAT_sectors; /* num of FAT sectors */
unsigned int root_dir; /* root dir cluster */
unsigned int dentries_per_clu; /* num of dentries per cluster */
unsigned int vol_flags; /* volume flags */
unsigned int vol_flags_persistent; /* volume flags to retain */
struct buffer_head *boot_bh; /* buffer_head of BOOT sector */
unsigned int map_clu; /* allocation bitmap start cluster */
unsigned int map_sectors; /* num of allocation bitmap sectors */
struct buffer_head **vol_amap; /* allocation bitmap */
unsigned short *vol_utbl; /* upcase table */
unsigned int clu_srch_ptr; /* cluster search pointer */
unsigned int used_clusters; /* number of used clusters */
struct mutex s_lock; /* superblock lock */
struct mutex bitmap_lock; /* bitmap lock */
struct exfat_mount_options options;
struct nls_table *nls_io; /* Charset used for input and display */
struct ratelimit_state ratelimit;
spinlock_t inode_hash_lock;
struct hlist_head inode_hashtable[EXFAT_HASH_SIZE];
struct rcu_head rcu;
};
#define EXFAT_CACHE_VALID 0
/*
* EXFAT file system inode in-memory data
*/
struct exfat_inode_info {
struct exfat_chain dir;
int entry;
unsigned int type;
unsigned short attr;
unsigned int start_clu;
unsigned char flags;
/*
* the copy of low 32bit of i_version to check
* the validation of hint_stat.
*/
unsigned int version;
/* hint for cluster last accessed */
struct exfat_hint hint_bmap;
/* hint for entry index we try to lookup next time */
struct exfat_hint hint_stat;
/* hint for first empty entry */
struct exfat_hint_femp hint_femp;
spinlock_t cache_lru_lock;
struct list_head cache_lru;
int nr_caches;
/* for avoiding the race between alloc and free */
unsigned int cache_valid_id;
/*
* NOTE: i_size_ondisk is 64bits, so must hold ->inode_lock to access.
* physically allocated size.
*/
loff_t i_size_ondisk;
/* block-aligned i_size (used in cont_write_begin) */
loff_t i_size_aligned;
/* on-disk position of directory entry or 0 */
loff_t i_pos;
/* hash by i_location */
struct hlist_node i_hash_fat;
/* protect bmap against truncate */
struct rw_semaphore truncate_lock;
struct inode vfs_inode;
/* File creation time */
struct timespec64 i_crtime;
};
static inline struct exfat_sb_info *EXFAT_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
static inline struct exfat_inode_info *EXFAT_I(struct inode *inode)
{
return container_of(inode, struct exfat_inode_info, vfs_inode);
}
/*
* If ->i_mode can't hold 0222 (i.e. ATTR_RO), we use ->i_attrs to
* save ATTR_RO instead of ->i_mode.
*
* If it's directory and !sbi->options.rodir, ATTR_RO isn't read-only
* bit, it's just used as flag for app.
*/
static inline int exfat_mode_can_hold_ro(struct inode *inode)
{
struct exfat_sb_info *sbi = EXFAT_SB(inode->i_sb);
if (S_ISDIR(inode->i_mode))
return 0;
if ((~sbi->options.fs_fmask) & 0222)
return 1;
return 0;
}
/* Convert attribute bits and a mask to the UNIX mode. */
static inline mode_t exfat_make_mode(struct exfat_sb_info *sbi,
unsigned short attr, mode_t mode)
{
if ((attr & ATTR_READONLY) && !(attr & ATTR_SUBDIR))
mode &= ~0222;
if (attr & ATTR_SUBDIR)
return (mode & ~sbi->options.fs_dmask) | S_IFDIR;
return (mode & ~sbi->options.fs_fmask) | S_IFREG;
}
/* Return the FAT attribute byte for this inode */
static inline unsigned short exfat_make_attr(struct inode *inode)
{
unsigned short attr = EXFAT_I(inode)->attr;
if (S_ISDIR(inode->i_mode))
attr |= ATTR_SUBDIR;
if (exfat_mode_can_hold_ro(inode) && !(inode->i_mode & 0222))
attr |= ATTR_READONLY;
return attr;
}
static inline void exfat_save_attr(struct inode *inode, unsigned short attr)
{
if (exfat_mode_can_hold_ro(inode))
EXFAT_I(inode)->attr = attr & (ATTR_RWMASK | ATTR_READONLY);
else
EXFAT_I(inode)->attr = attr & ATTR_RWMASK;
}
static inline bool exfat_is_last_sector_in_cluster(struct exfat_sb_info *sbi,
sector_t sec)
{
return ((sec - sbi->data_start_sector + 1) &
((1 << sbi->sect_per_clus_bits) - 1)) == 0;
}
static inline sector_t exfat_cluster_to_sector(struct exfat_sb_info *sbi,
unsigned int clus)
{
return ((sector_t)(clus - EXFAT_RESERVED_CLUSTERS) << sbi->sect_per_clus_bits) +
sbi->data_start_sector;
}
static inline int exfat_sector_to_cluster(struct exfat_sb_info *sbi,
sector_t sec)
{
return ((sec - sbi->data_start_sector) >> sbi->sect_per_clus_bits) +
EXFAT_RESERVED_CLUSTERS;
}
/* super.c */
int exfat_set_volume_dirty(struct super_block *sb);
int exfat_clear_volume_dirty(struct super_block *sb);
/* fatent.c */
#define exfat_get_next_cluster(sb, pclu) exfat_ent_get(sb, *(pclu), pclu)
int exfat_alloc_cluster(struct inode *inode, unsigned int num_alloc,
struct exfat_chain *p_chain, bool sync_bmap);
int exfat_free_cluster(struct inode *inode, struct exfat_chain *p_chain);
int exfat_ent_get(struct super_block *sb, unsigned int loc,
unsigned int *content);
int exfat_ent_set(struct super_block *sb, unsigned int loc,
unsigned int content);
int exfat_count_ext_entries(struct super_block *sb, struct exfat_chain *p_dir,
int entry, struct exfat_dentry *p_entry);
int exfat_chain_cont_cluster(struct super_block *sb, unsigned int chain,
unsigned int len);
int exfat_zeroed_cluster(struct inode *dir, unsigned int clu);
int exfat_find_last_cluster(struct super_block *sb, struct exfat_chain *p_chain,
unsigned int *ret_clu);
int exfat_count_num_clusters(struct super_block *sb,
struct exfat_chain *p_chain, unsigned int *ret_count);
/* balloc.c */
int exfat_load_bitmap(struct super_block *sb);
void exfat_free_bitmap(struct exfat_sb_info *sbi);
int exfat_set_bitmap(struct inode *inode, unsigned int clu, bool sync);
void exfat_clear_bitmap(struct inode *inode, unsigned int clu, bool sync);
unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu);
int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count);
int exfat_trim_fs(struct inode *inode, struct fstrim_range *range);
/* file.c */
extern const struct file_operations exfat_file_operations;
int __exfat_truncate(struct inode *inode, loff_t new_size);
void exfat_truncate(struct inode *inode, loff_t size);
int exfat_setattr(struct user_namespace *mnt_userns, struct dentry *dentry,
struct iattr *attr);
int exfat_getattr(struct user_namespace *mnt_userns, const struct path *path,
struct kstat *stat, unsigned int request_mask,
unsigned int query_flags);
int exfat_file_fsync(struct file *file, loff_t start, loff_t end, int datasync);
long exfat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
long exfat_compat_ioctl(struct file *filp, unsigned int cmd,
unsigned long arg);
/* namei.c */
extern const struct dentry_operations exfat_dentry_ops;
extern const struct dentry_operations exfat_utf8_dentry_ops;
/* cache.c */
int exfat_cache_init(void);
void exfat_cache_shutdown(void);
void exfat_cache_inval_inode(struct inode *inode);
int exfat_get_cluster(struct inode *inode, unsigned int cluster,
unsigned int *fclus, unsigned int *dclus,
unsigned int *last_dclus, int allow_eof);
/* dir.c */
extern const struct inode_operations exfat_dir_inode_operations;
extern const struct file_operations exfat_dir_operations;
unsigned int exfat_get_entry_type(struct exfat_dentry *p_entry);
int exfat_init_dir_entry(struct inode *inode, struct exfat_chain *p_dir,
int entry, unsigned int type, unsigned int start_clu,
unsigned long long size);
int exfat_init_ext_entry(struct inode *inode, struct exfat_chain *p_dir,
int entry, int num_entries, struct exfat_uni_name *p_uniname);
int exfat_remove_entries(struct inode *inode, struct exfat_chain *p_dir,
int entry, int order, int num_entries);
int exfat_update_dir_chksum(struct inode *inode, struct exfat_chain *p_dir,
int entry);
void exfat_update_dir_chksum_with_entry_set(struct exfat_entry_set_cache *es);
int exfat_calc_num_entries(struct exfat_uni_name *p_uniname);
int exfat_find_dir_entry(struct super_block *sb, struct exfat_inode_info *ei,
struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
int num_entries, unsigned int type, struct exfat_hint *hint_opt);
int exfat_alloc_new_dir(struct inode *inode, struct exfat_chain *clu);
int exfat_find_location(struct super_block *sb, struct exfat_chain *p_dir,
int entry, sector_t *sector, int *offset);
struct exfat_dentry *exfat_get_dentry(struct super_block *sb,
struct exfat_chain *p_dir, int entry, struct buffer_head **bh,
sector_t *sector);
struct exfat_dentry *exfat_get_dentry_cached(struct exfat_entry_set_cache *es,
int num);
struct exfat_entry_set_cache *exfat_get_dentry_set(struct super_block *sb,
struct exfat_chain *p_dir, int entry, unsigned int type);
int exfat_free_dentry_set(struct exfat_entry_set_cache *es, int sync);
int exfat_count_dir_entries(struct super_block *sb, struct exfat_chain *p_dir);
/* inode.c */
extern const struct inode_operations exfat_file_inode_operations;
void exfat_sync_inode(struct inode *inode);
struct inode *exfat_build_inode(struct super_block *sb,
struct exfat_dir_entry *info, loff_t i_pos);
void exfat_hash_inode(struct inode *inode, loff_t i_pos);
void exfat_unhash_inode(struct inode *inode);
struct inode *exfat_iget(struct super_block *sb, loff_t i_pos);
int exfat_write_inode(struct inode *inode, struct writeback_control *wbc);
void exfat_evict_inode(struct inode *inode);
int exfat_block_truncate_page(struct inode *inode, loff_t from);
/* exfat/nls.c */
unsigned short exfat_toupper(struct super_block *sb, unsigned short a);
int exfat_uniname_ncmp(struct super_block *sb, unsigned short *a,
unsigned short *b, unsigned int len);
int exfat_utf16_to_nls(struct super_block *sb,
struct exfat_uni_name *uniname, unsigned char *p_cstring,
int len);
int exfat_nls_to_utf16(struct super_block *sb,
const unsigned char *p_cstring, const int len,
struct exfat_uni_name *uniname, int *p_lossy);
int exfat_create_upcase_table(struct super_block *sb);
void exfat_free_upcase_table(struct exfat_sb_info *sbi);
/* exfat/misc.c */
void __exfat_fs_error(struct super_block *sb, int report, const char *fmt, ...)
__printf(3, 4) __cold;
#define exfat_fs_error(sb, fmt, args...) \
__exfat_fs_error(sb, 1, fmt, ## args)
#define exfat_fs_error_ratelimit(sb, fmt, args...) \
__exfat_fs_error(sb, __ratelimit(&EXFAT_SB(sb)->ratelimit), \
fmt, ## args)
void exfat_msg(struct super_block *sb, const char *lv, const char *fmt, ...)
__printf(3, 4) __cold;
#define exfat_err(sb, fmt, ...) \
exfat_msg(sb, KERN_ERR, fmt, ##__VA_ARGS__)
#define exfat_warn(sb, fmt, ...) \
exfat_msg(sb, KERN_WARNING, fmt, ##__VA_ARGS__)
#define exfat_info(sb, fmt, ...) \
exfat_msg(sb, KERN_INFO, fmt, ##__VA_ARGS__)
void exfat_get_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
u8 tz, __le16 time, __le16 date, u8 time_cs);
void exfat_truncate_atime(struct timespec64 *ts);
void exfat_set_entry_time(struct exfat_sb_info *sbi, struct timespec64 *ts,
u8 *tz, __le16 *time, __le16 *date, u8 *time_cs);
u16 exfat_calc_chksum16(void *data, int len, u16 chksum, int type);
u32 exfat_calc_chksum32(void *data, int len, u32 chksum, int type);
void exfat_update_bh(struct buffer_head *bh, int sync);
int exfat_update_bhs(struct buffer_head **bhs, int nr_bhs, int sync);
void exfat_chain_set(struct exfat_chain *ec, unsigned int dir,
unsigned int size, unsigned char flags);
void exfat_chain_dup(struct exfat_chain *dup, struct exfat_chain *ec);
#endif /* !_EXFAT_FS_H */