projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* |
| 2 | * Wrapper functions for accessing the file_struct fd array. | |
| 3 | */ | |
| 4 | ||
| 5 | #ifndef __LINUX_FILE_H | |
| 6 | #define __LINUX_FILE_H | |
| 7 | ||
| 8 | #include <asm/atomic.h> | |
| 9 | #include <linux/posix_types.h> | |
| 10 | #include <linux/compiler.h> | |
| 11 | #include <linux/spinlock.h> | |
| 12 | ||
| 13 | /* | |
| 14 | * The default fd array needs to be at least BITS_PER_LONG, | |
| 15 | * as this is the granularity returned by copy_fdset(). | |
| 16 | */ | |
| 17 | #define NR_OPEN_DEFAULT BITS_PER_LONG | |
| 18 | ||
| 19 | /* | |
| 20 | * Open file table structure | |
| 21 | */ | |
| 22 | struct files_struct { | |
| 23 | atomic_t count; | |
| 24 | spinlock_t file_lock; /* Protects all the below members. Nests inside tsk->alloc_lock */ | |
| 25 | int max_fds; | |
| 26 | int max_fdset; | |
| 27 | int next_fd; | |
| 28 | struct file ** fd; /* current fd array */ | |
| 29 | fd_set *close_on_exec; | |
| 30 | fd_set *open_fds; | |
| 31 | fd_set close_on_exec_init; | |
| 32 | fd_set open_fds_init; | |
| 33 | struct file * fd_array[NR_OPEN_DEFAULT]; | |
| 34 | }; | |
| 35 | ||
| 36 | extern void FASTCALL(__fput(struct file *)); | |
| 37 | extern void FASTCALL(fput(struct file *)); | |
| 38 | ||
| 39 | static inline void fput_light(struct file *file, int fput_needed) | |
| 40 | { | |
| 41 | if (unlikely(fput_needed)) | |
| 42 | fput(file); | |
| 43 | } | |
| 44 | ||
| 45 | extern struct file * FASTCALL(fget(unsigned int fd)); | |
| 46 | extern struct file * FASTCALL(fget_light(unsigned int fd, int *fput_needed)); | |
| 47 | extern void FASTCALL(set_close_on_exec(unsigned int fd, int flag)); | |
| 48 | extern void put_filp(struct file *); | |
| 49 | extern int get_unused_fd(void); | |
| 50 | extern void FASTCALL(put_unused_fd(unsigned int fd)); | |
| 51 | struct kmem_cache_s; | |
| 52 | extern void filp_ctor(void * objp, struct kmem_cache_s *cachep, unsigned long cflags); | |
| 53 | extern void filp_dtor(void * objp, struct kmem_cache_s *cachep, unsigned long dflags); | |
| 54 | ||
| 55 | extern struct file ** alloc_fd_array(int); | |
| 56 | extern void free_fd_array(struct file **, int); | |
| 57 | ||
| 58 | extern fd_set *alloc_fdset(int); | |
| 59 | extern void free_fdset(fd_set *, int); | |
| 60 | ||
| 61 | extern int expand_files(struct files_struct *, int nr); | |
| 62 | ||
| 63 | static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd) | |
| 64 | { | |
| 65 | struct file * file = NULL; | |
| 66 | ||
| 67 | if (fd < files->max_fds) | |
| 68 | file = files->fd[fd]; | |
| 69 | return file; | |
| 70 | } | |
| 71 | ||
| 72 | /* | |
| 73 | * Check whether the specified fd has an open file. | |
| 74 | */ | |
| 75 | #define fcheck(fd) fcheck_files(current->files, fd) | |
| 76 | ||
| 77 | extern void FASTCALL(fd_install(unsigned int fd, struct file * file)); | |
| 78 | ||
| 79 | struct task_struct; | |
| 80 | ||
| 81 | struct files_struct *get_files_struct(struct task_struct *); | |
| 82 | void FASTCALL(put_files_struct(struct files_struct *fs)); | |
| 83 | ||
| 84 | #endif /* __LINUX_FILE_H */ |