fs/fat/fat.h
Source file repositories/reference/linux-study-clean/fs/fat/fat.h
File Facts
- System
- Linux kernel
- Corpus path
fs/fat/fat.h- Extension
.h- Size
- 16503 bytes
- Lines
- 494
- Domain
- Core OS
- Bucket
- VFS And Filesystem Core
- Inferred role
- Core OS: operation-table or driver-model contract
- Status
- pattern implementation candidate
Why This File Exists
Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.
- Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/buffer_head.hlinux/nls.hlinux/hash.hlinux/ratelimit.hlinux/msdos_fs.hlinux/fs_context.hlinux/fs_parser.h
Detected Declarations
struct file_kattrstruct fat_mount_optionsstruct msdos_sb_infostruct msdos_inode_infostruct fat_slot_infostruct fat_entryfunction systemfunction is_fat16function is_fat32function max_fatfunction fat_mode_can_hold_rofunction fat_make_modefunction fat_make_attrsfunction fat_save_attrsfunction fat_checksumfunction fat_clus_to_blknrfunction fat_get_blknr_offsetfunction fat_i_pos_readfunction fat16_towcharfunction fat_get_startfunction fat_set_startfunction fatwchar_to16function fatent_initfunction fatent_set_entryfunction fatent_brelsefunction fat_valid_entryfunction fat_dir_hash
Annotated Snippet
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_scan_logstart(struct inode *dir, int i_logstart,
struct fat_slot_info *sinfo);
extern int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
struct msdos_dir_entry **de);
extern int fat_alloc_new_dir(struct inode *dir, struct timespec64 *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;
}
static inline bool fat_valid_entry(struct msdos_sb_info *sbi, int entry)
{
return FAT_START_ENT <= entry && entry < sbi->max_cluster;
}
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);
extern int fat_trim_fs(struct inode *inode, struct fstrim_range *range);
/* fat/file.c */
extern long fat_generic_ioctl(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 mnt_idmap *idmap, struct dentry *dentry,
struct iattr *attr);
extern void fat_truncate_blocks(struct inode *inode, loff_t offset);
extern int fat_getattr(struct mnt_idmap *idmap,
const struct path *path, struct kstat *stat,
u32 request_mask, unsigned int flags);
int fat_fileattr_get(struct dentry *dentry, struct file_kattr *fa);
extern int fat_file_fsync(struct file *file, loff_t start, loff_t end,
int datasync);
/* fat/inode.c */
extern int fat_block_truncate_page(struct inode *inode, loff_t from);
extern void fat_attach(struct inode *inode, loff_t i_pos);
extern void fat_detach(struct inode *inode);
Annotation
- Immediate include surface: `linux/buffer_head.h`, `linux/nls.h`, `linux/hash.h`, `linux/ratelimit.h`, `linux/msdos_fs.h`, `linux/fs_context.h`, `linux/fs_parser.h`.
- Detected declarations: `struct file_kattr`, `struct fat_mount_options`, `struct msdos_sb_info`, `struct msdos_inode_info`, `struct fat_slot_info`, `struct fat_entry`, `function system`, `function is_fat16`, `function is_fat32`, `function max_fat`.
- Atlas domain: Core OS / VFS And Filesystem Core.
- Implementation status: pattern implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.