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 | ||
badf1662 DS |
19 | struct fdtable { |
20 | unsigned int max_fds; | |
21 | int max_fdset; | |
22 | int next_fd; | |
23 | struct file ** fd; /* current fd array */ | |
24 | fd_set *close_on_exec; | |
25 | fd_set *open_fds; | |
26 | }; | |
27 | ||
1da177e4 LT |
28 | /* |
29 | * Open file table structure | |
30 | */ | |
31 | struct files_struct { | |
32 | atomic_t count; | |
33 | spinlock_t file_lock; /* Protects all the below members. Nests inside tsk->alloc_lock */ | |
badf1662 | 34 | struct fdtable fdtab; |
1da177e4 LT |
35 | fd_set close_on_exec_init; |
36 | fd_set open_fds_init; | |
37 | struct file * fd_array[NR_OPEN_DEFAULT]; | |
38 | }; | |
39 | ||
badf1662 DS |
40 | #define files_fdtable(files) (&(files)->fdtab) |
41 | ||
1da177e4 LT |
42 | extern void FASTCALL(__fput(struct file *)); |
43 | extern void FASTCALL(fput(struct file *)); | |
44 | ||
45 | static inline void fput_light(struct file *file, int fput_needed) | |
46 | { | |
47 | if (unlikely(fput_needed)) | |
48 | fput(file); | |
49 | } | |
50 | ||
51 | extern struct file * FASTCALL(fget(unsigned int fd)); | |
52 | extern struct file * FASTCALL(fget_light(unsigned int fd, int *fput_needed)); | |
53 | extern void FASTCALL(set_close_on_exec(unsigned int fd, int flag)); | |
54 | extern void put_filp(struct file *); | |
55 | extern int get_unused_fd(void); | |
56 | extern void FASTCALL(put_unused_fd(unsigned int fd)); | |
57 | struct kmem_cache_s; | |
58 | extern void filp_ctor(void * objp, struct kmem_cache_s *cachep, unsigned long cflags); | |
59 | extern void filp_dtor(void * objp, struct kmem_cache_s *cachep, unsigned long dflags); | |
60 | ||
61 | extern struct file ** alloc_fd_array(int); | |
62 | extern void free_fd_array(struct file **, int); | |
63 | ||
64 | extern fd_set *alloc_fdset(int); | |
65 | extern void free_fdset(fd_set *, int); | |
66 | ||
67 | extern int expand_files(struct files_struct *, int nr); | |
68 | ||
69 | static inline struct file * fcheck_files(struct files_struct *files, unsigned int fd) | |
70 | { | |
71 | struct file * file = NULL; | |
badf1662 | 72 | struct fdtable *fdt = files_fdtable(files); |
1da177e4 | 73 | |
badf1662 DS |
74 | if (fd < fdt->max_fds) |
75 | file = fdt->fd[fd]; | |
1da177e4 LT |
76 | return file; |
77 | } | |
78 | ||
79 | /* | |
80 | * Check whether the specified fd has an open file. | |
81 | */ | |
82 | #define fcheck(fd) fcheck_files(current->files, fd) | |
83 | ||
84 | extern void FASTCALL(fd_install(unsigned int fd, struct file * file)); | |
85 | ||
86 | struct task_struct; | |
87 | ||
88 | struct files_struct *get_files_struct(struct task_struct *); | |
89 | void FASTCALL(put_files_struct(struct files_struct *fs)); | |
90 | ||
91 | #endif /* __LINUX_FILE_H */ |