/* ************************************************************************* VXEXT fs - VxWorks extended DOS filesystem support Copyright (c) 2004-2009 by Jens Langner This filesystem module is a reverse engineered implementation of the so called VXEXT1.0 extended DOS filesystem shipped with the VxWorks 5.2+ RTOS operating system. The sources are largly based on the FAT and MSDOS filesystem routines found in the main Linux kernel sources which are copyright by their respecitive authors. However, minor cosmetic changes have been made and non-required parts were removed wherever possible. 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, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA $Id: fat.h 58 2010-05-03 08:17:45Z langner $ ***************************************************************************/ #ifndef _FAT_H #define _FAT_H #include #include /* * The MS-DOS filesystem constants/structures */ #define SECTOR_SIZE 512 /* sector size (bytes) */ #define SECTOR_BITS 9 /* log2(SECTOR_SIZE) */ #define MSDOS_DPB (MSDOS_DPS) /* dir entries per block */ #define MSDOS_DPB_BITS 3 /* log2(MSDOS_DPB) */ #define MSDOS_DPS (SECTOR_SIZE / sizeof(struct msdos_dir_entry)) #define MSDOS_DPS_BITS 3 /* log2(MSDOS_DPS) */ #undef MSDOS_SUPER_MAGIC #define MSDOS_SUPER_MAGIC 0x5657 // VW #define MSDOS_ROOT_INO 1 /* == MINIX_ROOT_INO */ #define MSDOS_DIR_BITS 6 /* log2(sizeof(struct msdos_dir_entry)) */ /* directory limit */ #define FAT_MAX_DIR_ENTRIES (65536) #define FAT_MAX_DIR_SIZE (FAT_MAX_DIR_ENTRIES << MSDOS_DIR_BITS) #define ATTR_NONE 0 /* no attribute bits */ #define ATTR_RO 1 /* read-only */ #define ATTR_HIDDEN 2 /* hidden */ #define ATTR_SYS 4 /* system */ #define ATTR_VOLUME 8 /* volume label */ #define ATTR_DIR 16 /* directory */ #define ATTR_ARCH 32 /* archived */ /* attribute bits that are copied "as is" */ #define ATTR_UNUSED (ATTR_VOLUME | ATTR_ARCH | ATTR_SYS | ATTR_HIDDEN) /* bits that are used by the Windows 95/Windows NT extended FAT */ #define ATTR_EXT (ATTR_RO | ATTR_HIDDEN | ATTR_SYS | ATTR_VOLUME) #define CASE_LOWER_BASE 8 /* base is lower case */ #define CASE_LOWER_EXT 16 /* extension is lower case */ #define DELETED_FLAG 0xe5 /* marks file as deleted when in name[0] */ #define IS_FREE(n) (!*(n) || *(n) == DELETED_FLAG) /* valid file mode bits */ #define MSDOS_VALID_MODE (S_IFREG | S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO) /* Convert attribute bits and a mask to the UNIX mode. */ #define MSDOS_MKMODE(a, m) (m & (a & ATTR_RO ? S_IRUGO|S_IXUGO : S_IRWXUGO)) #define MSDOS_NAME 40 /* maximum name length */ #define MSDOS_LONGNAME 40 /* maximum name length */ #define MSDOS_SLOTS 21 /* max # of slots for short and long names */ #define MSDOS_DOT ". " // "." #define MSDOS_DOTDOT ".. " // ".." #define FAT_FIRST_ENT(s, x) (0xFF00 | (x)) /* start of data cluster's entry (number of reserved clusters) */ #define FAT_START_ENT 2 /* maximum number of clusters */ #define MAX_FAT12 0xFF4 #define MAX_FAT16 0xFFF4 #define MAX_FAT32 0x0FFFFFF6 #define MAX_FAT(s) 0xFFFE /* bad cluster mark */ #define BAD_FAT12 0xFF7 #define BAD_FAT16 0xFFF7 #define BAD_FAT32 0x0FFFFFF7 /* standard EOF */ #define EOF_FAT12 0xFFF #define EOF_FAT16 0xFFFF #define EOF_FAT32 0x0FFFFFFF #define FAT_ENT_FREE (0) #define FAT_ENT_BAD (BAD_FAT16) #define FAT_ENT_EOF (EOF_FAT16) #define FAT_FSINFO_SIG1 0x41615252 #define FAT_FSINFO_SIG2 0x61417272 #define IS_FSINFO(x) (le32_to_cpu((x)->signature1) == FAT_FSINFO_SIG1 \ && le32_to_cpu((x)->signature2) == FAT_FSINFO_SIG2) struct __fat_dirent { long d_ino; __kernel_off_t d_off; unsigned short d_reclen; char d_name[256]; /* We must not include limits.h! */ }; /* * ioctl commands */ #define VFAT_IOCTL_READDIR_BOTH _IOR('r', 1, struct __fat_dirent[2]) #define VFAT_IOCTL_READDIR_SHORT _IOR('r', 2, struct __fat_dirent[2]) /* has used 0x72 ('r') in collision, so skip a few */ #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32) #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32) struct fat_boot_sector { __u8 ignored[3]; /* Boot strap short or near jump */ __u8 system_id[8]; /* Name - can be used to special case partition manager volumes */ __u8 sector_size[2]; /* bytes per logical sector */ __u8 sec_per_clus; /* sectors/cluster */ __le16 reserved; /* reserved sectors */ __u8 fats; /* number of FATs */ __u8 dir_entries[2]; /* root directory entries */ __u8 sectors[2]; /* number of sectors */ __u8 media; /* media code */ __le16 fat_length; /* sectors/FAT */ __le16 secs_track; /* sectors per track */ __le16 heads; /* number of heads */ __le32 hidden; /* hidden sectors (unused) */ __le32 total_sect; /* number of sectors (if sectors == 0) */ /* The following fields are only used by FAT32 */ __le32 fat32_length; /* sectors/FAT */ __le16 flags; /* bit 8: fat mirroring, low 4: active fat */ __u8 version[2]; /* major, minor filesystem version */ __le32 root_cluster; /* first cluster in root directory */ __le16 info_sector; /* filesystem info sector */ __le16 backup_boot; /* backup boot sector */ #if defined(VXEXT_FS) __le16 reserved2; /* Unused */ __le16 sec_per_clus2; /* VXEXT stores the real sectors/clusters here */ __le16 reserved3[4]; /* Unused */ #else __le16 reserved2[6]; /* Unused */ #endif }; struct fat_boot_fsinfo { __le32 signature1; /* 0x41615252L */ __le32 reserved1[120]; /* Nothing as far as I can tell */ __le32 signature2; /* 0x61417272L */ __le32 free_clusters; /* Free cluster count. -1 if unknown */ __le32 next_cluster; /* Most recently allocated cluster */ __le32 reserved2[4]; }; struct msdos_dir_entry { __u8 name[MSDOS_NAME]; // 0x00 - Filename max. 40 chars __u8 reserved[13]; // 0x28 - Reserved __u8 attr; // 0x35 - File attributes __le16 time; // 0x36 - File creation time (ctime) __le16 date; // 0x38 - File creation date (cdate) __le16 start; // 0x40 - Starting cluster number __le32 size; // 0x42 - File size (in bytes) }; /* Up to 13 characters of the name */ struct msdos_dir_slot { __u8 id; /* sequence number for slot */ __u8 name0_4[10]; /* first 5 characters in name */ __u8 attr; /* attribute byte */ __u8 reserved; /* always 0 */ __u8 alias_checksum; /* checksum for 8.3 alias */ __u8 name5_10[12]; /* 6 more characters in name */ __le16 start; /* starting cluster number, 0 in long slots */ __u8 name11_12[4]; /* last 2 characters in name */ }; #ifdef __KERNEL__ #include #include #include #include #include /* * vfat shortname flags */ #define VFAT_SFN_DISPLAY_LOWER 0x0001 /* convert to lowercase for display */ #define VFAT_SFN_DISPLAY_WIN95 0x0002 /* emulate win95 rule for display */ #define VFAT_SFN_DISPLAY_WINNT 0x0004 /* emulate winnt rule for display */ #define VFAT_SFN_CREATE_WIN95 0x0100 /* emulate win95 rule for create */ #define VFAT_SFN_CREATE_WINNT 0x0200 /* emulate winnt rule for create */ #define FAT_ERRORS_CONT 1 /* ignore error and continue */ #define FAT_ERRORS_PANIC 2 /* panic on error */ #define FAT_ERRORS_RO 3 /* remount r/o on error */ struct fat_mount_options { uid_t fs_uid; gid_t fs_gid; unsigned short fs_fmask; unsigned short fs_dmask; unsigned short codepage; /* Codepage for shortname conversions */ char *iocharset; /* Charset used for filename input/display */ unsigned short shortname; /* flags for shortname display/create rule */ unsigned char name_check; /* r = relaxed, n = normal, s = strict */ unsigned char errors; /* On error: continue, panic, remount-ro */ unsigned short allow_utime;/* permission for setting the [am]time */ unsigned quiet:1, /* set = fake successful chmods and chowns */ showexec:1, /* set = only set x bit for com/exe/bat */ sys_immutable:1, /* set = system files are immutable */ dotsOK:1, /* set = hidden and system files are named '.filename' */ isvfat:1, /* 0=no vfat long filename support, 1=vfat support */ utf8:1, /* Use of UTF-8 character set (Default) */ unicode_xlate:1, /* create escape sequences for unhandled Unicode */ numtail:1, /* Does first alias have a numeric '~1' type tail? */ flush:1, /* write things quickly */ nocase:1, /* Does this need case conversion? 0=need case conversion*/ usefree:1, /* Use free_clusters for FAT32 */ tz_utc:1, /* Filesystem timestamps are in UTC */ rodir:1; /* allow ATTR_RO for directory */ }; #define FAT_HASH_BITS 8 #define FAT_HASH_SIZE (1UL << FAT_HASH_BITS) #define FAT_HASH_MASK (FAT_HASH_SIZE-1) /* * MS-DOS file system in-core superblock data */ struct msdos_sb_info { unsigned short sec_per_clus; /* sectors/cluster */ unsigned short cluster_bits; /* log2(cluster_size) */ unsigned int cluster_size; /* cluster size */ unsigned char fats,fat_bits; /* number of FATs, FAT bits (12 or 16) */ unsigned short fat_start; unsigned long fat_length; /* FAT start & length (sec.) */ unsigned long dir_start; unsigned short dir_entries; /* root dir start & entries */ unsigned long data_start; /* first data sector */ unsigned long max_cluster; /* maximum cluster number */ unsigned long root_cluster; /* first cluster of the root directory */ unsigned long fsinfo_sector; /* sector number of FAT32 fsinfo */ struct mutex fat_lock; unsigned int prev_free; /* previously allocated cluster number */ unsigned int free_clusters; /* -1 if undefined */ unsigned int free_clus_valid; /* is free_clusters valid? */ struct fat_mount_options options; struct nls_table *nls_disk; /* Codepage used on disk */ struct nls_table *nls_io; /* Charset used for input and display */ const void *dir_ops; /* Opaque; default directory operations */ int dir_per_block; /* dir entries per block */ int dir_per_block_bits; /* log2(dir_per_block) */ int fatent_shift; struct fatent_operations *fatent_ops; struct inode *fat_inode; spinlock_t inode_hash_lock; struct hlist_head inode_hashtable[FAT_HASH_SIZE]; }; #define FAT_CACHE_VALID 0 /* special case for valid cache */ /* * MS-DOS file system inode data in memory */ struct msdos_inode_info { spinlock_t cache_lru_lock; struct list_head cache_lru; int nr_caches; /* for avoiding the race between fat_free() and fat_get_cluster() */ unsigned int cache_valid_id; loff_t mmu_private; int i_start; /* first cluster or 0 */ int i_logstart; /* logical first cluster */ int i_attrs; /* unused attribute bits */ loff_t i_pos; /* on-disk position of directory entry or 0 */ struct hlist_node i_fat_hash; /* hash by i_location */ struct inode vfs_inode; }; struct fat_slot_info { loff_t i_pos; /* on-disk position of directory entry */ loff_t slot_off; /* offset for slot or de start */ int nr_slots; /* number of slots + 1(de) in filename */ struct msdos_dir_entry *de; struct buffer_head *bh; }; static inline struct msdos_sb_info *MSDOS_SB(struct super_block *sb) { return sb->s_fs_info; } static inline struct msdos_inode_info *MSDOS_I(struct inode *inode) { return container_of(inode, struct msdos_inode_info, vfs_inode); } /* * If ->i_mode can't hold S_IWUGO (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 fat_mode_can_hold_ro(struct inode *inode) { struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb); mode_t mask; if (S_ISDIR(inode->i_mode)) { if (!sbi->options.rodir) return 0; mask = ~sbi->options.fs_dmask; } else mask = ~sbi->options.fs_fmask; if (!(mask & S_IWUGO)) return 0; return 1; } /* Convert attribute bits and a mask to the UNIX mode. */ static inline mode_t fat_make_mode(struct msdos_sb_info *sbi, u8 attrs, mode_t mode) { if (attrs & ATTR_RO && !((attrs & ATTR_DIR) && !sbi->options.rodir)) mode &= ~S_IWUGO; if (attrs & ATTR_DIR) return (mode & ~sbi->options.fs_dmask) | S_IFDIR; else return (mode & ~sbi->options.fs_fmask) | S_IFREG; } /* Return the FAT attribute byte for this inode */ static inline u8 fat_make_attrs(struct inode *inode) { u8 attrs = MSDOS_I(inode)->i_attrs; if (S_ISDIR(inode->i_mode)) attrs |= ATTR_DIR; if (fat_mode_can_hold_ro(inode) && !(inode->i_mode & S_IWUGO)) attrs |= ATTR_RO; return attrs; } static inline void fat_save_attrs(struct inode *inode, u8 attrs) { if (fat_mode_can_hold_ro(inode)) MSDOS_I(inode)->i_attrs = attrs & ATTR_UNUSED; else MSDOS_I(inode)->i_attrs = attrs & (ATTR_UNUSED | ATTR_RO); } static inline unsigned char fat_checksum(const __u8 *name) { unsigned char s = name[0]; s = (s<<7) + (s>>1) + name[1]; s = (s<<7) + (s>>1) + name[2]; s = (s<<7) + (s>>1) + name[3]; s = (s<<7) + (s>>1) + name[4]; s = (s<<7) + (s>>1) + name[5]; s = (s<<7) + (s>>1) + name[6]; s = (s<<7) + (s>>1) + name[7]; s = (s<<7) + (s>>1) + name[8]; s = (s<<7) + (s>>1) + name[9]; s = (s<<7) + (s>>1) + name[10]; return s; } static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) { return ((sector_t)clus - FAT_START_ENT) * sbi->sec_per_clus + sbi->data_start; } static inline void fat16_towchar(wchar_t *dst, const __u8 *src, size_t len) { #ifdef __BIG_ENDIAN while (len--) { *dst++ = src[0] | (src[1] << 8); src += 2; } #else memcpy(dst, src, len * 2); #endif } static inline void fatwchar_to16(__u8 *dst, const wchar_t *src, size_t len) { #ifdef __BIG_ENDIAN while (len--) { dst[0] = *src & 0x00FF; dst[1] = (*src & 0xFF00) >> 8; dst += 2; src++; } #else memcpy(dst, src, len * 2); #endif } /* media of boot sector */ static inline int fat_valid_media(u8 media) { return 0xf8 <= media || media == 0xf0; } /* fat/cache.c */ extern void fat_cache_inval_inode(struct inode *inode); extern int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus); extern int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys, unsigned long *mapped_blocks, int create); /* fat/dir.c */ extern const struct file_operations fat_dir_operations; extern int fat_search_long(struct inode *inode, const unsigned char *name, int name_len, struct fat_slot_info *sinfo); extern int fat_dir_empty(struct inode *dir); extern int fat_subdirs(struct inode *dir); extern int fat_scan(struct inode *dir, const unsigned char *name, struct fat_slot_info *sinfo); extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh, struct msdos_dir_entry **de, loff_t *i_pos); extern int fat_alloc_new_dir(struct inode *dir, struct timespec *ts); extern int fat_add_entries(struct inode *dir, void *slots, int nr_slots, struct fat_slot_info *sinfo); extern int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo); /* fat/fatent.c */ struct fat_entry { int entry; union { u8 *ent12_p[2]; __le16 *ent16_p; __le32 *ent32_p; } u; int nr_bhs; struct buffer_head *bhs[2]; struct inode *fat_inode; }; static inline void fatent_init(struct fat_entry *fatent) { fatent->nr_bhs = 0; fatent->entry = 0; fatent->u.ent32_p = NULL; fatent->bhs[0] = fatent->bhs[1] = NULL; fatent->fat_inode = NULL; } static inline void fatent_set_entry(struct fat_entry *fatent, int entry) { fatent->entry = entry; fatent->u.ent32_p = NULL; } static inline void fatent_brelse(struct fat_entry *fatent) { int i; fatent->u.ent32_p = NULL; for (i = 0; i < fatent->nr_bhs; i++) brelse(fatent->bhs[i]); fatent->nr_bhs = 0; fatent->bhs[0] = fatent->bhs[1] = NULL; fatent->fat_inode = NULL; } extern void fat_ent_access_init(struct super_block *sb); extern int fat_ent_read(struct inode *inode, struct fat_entry *fatent, int entry); extern int fat_ent_write(struct inode *inode, struct fat_entry *fatent, int new, int wait); extern int fat_alloc_clusters(struct inode *inode, int *cluster, int nr_cluster); extern int fat_free_clusters(struct inode *inode, int cluster); extern int fat_count_free_clusters(struct super_block *sb); /* fat/file.c */ extern int fat_generic_ioctl(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg); extern const struct file_operations fat_file_operations; extern const struct inode_operations fat_file_inode_operations; extern int fat_setattr(struct dentry * dentry, struct iattr * attr); extern void fat_truncate(struct inode *inode); extern int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat); extern int fat_file_fsync(struct file *file, struct dentry *dentry, int datasync); /* fat/inode.c */ extern void fat_attach(struct inode *inode, loff_t i_pos); extern void fat_detach(struct inode *inode); extern struct inode *fat_iget(struct super_block *sb, loff_t i_pos); extern struct inode *fat_build_inode(struct super_block *sb, struct msdos_dir_entry *de, loff_t i_pos); extern int fat_sync_inode(struct inode *inode); extern int fat_fill_super(struct super_block *sb, void *data, int silent, const struct inode_operations *fs_dir_inode_ops, int isvfat); extern int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2); /* fat/misc.c */ extern void fat_fs_error(struct super_block *s, const char *fmt, ...) __attribute__ ((format (printf, 2, 3))) __cold; extern int fat_clusters_flush(struct super_block *sb); extern int fat_chain_add(struct inode *inode, int new_dclus, int nr_cluster); extern void fat_time_fat2unix(struct msdos_sb_info *sbi, struct timespec *ts, __le16 __time, __le16 __date, u8 time_cs); extern void fat_time_unix2fat(struct msdos_sb_info *sbi, struct timespec *ts, __le16 *time, __le16 *date, u8 *time_cs); extern int fat_sync_bhs(struct buffer_head **bhs, int nr_bhs); int fat_cache_init(void); void fat_cache_destroy(void); /* helper for printk */ typedef unsigned long long llu; #endif /* __KERNEL__ */ #endif