1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Wrapper functions for accessing the file_struct fd array.
4 */
5
6#ifndef __LINUX_FILE_H
7#define __LINUX_FILE_H
8
9#include <linux/compiler.h>
10#include <linux/types.h>
11#include <linux/posix_types.h>
12#include <linux/errno.h>
13
14struct file;
15
16extern void fput(struct file *);
17
18struct file_operations;
19struct task_struct;
20struct vfsmount;
21struct dentry;
22struct inode;
23struct path;
24extern struct file *alloc_file_pseudo(struct inode *, struct vfsmount *,
25 const char *, int flags, const struct file_operations *);
26extern struct file *alloc_file_clone(struct file *, int flags,
27 const struct file_operations *);
28
29static inline void fput_light(struct file *file, int fput_needed)
30{
31 if (fput_needed)
32 fput(file);
33}
34
35struct fd {
36 struct file *file;
37 unsigned int flags;
38};
39#define FDPUT_FPUT 1
40#define FDPUT_POS_UNLOCK 2
41
42static inline void fdput(struct fd fd)
43{
44 if (fd.flags & FDPUT_FPUT)
45 fput(fd.file);
46}
47
48extern struct file *fget(unsigned int fd);
49extern struct file *fget_raw(unsigned int fd);
50extern struct file *fget_task(struct task_struct *task, unsigned int fd);
51extern unsigned long __fdget(unsigned int fd);
52extern unsigned long __fdget_raw(unsigned int fd);
53extern unsigned long __fdget_pos(unsigned int fd);
54extern void __f_unlock_pos(struct file *);
55
56static inline struct fd __to_fd(unsigned long v)
57{
58 return (struct fd){(struct file *)(v & ~3),v & 3};
59}
60
61static inline struct fd fdget(unsigned int fd)
62{
63 return __to_fd(__fdget(fd));
64}
65
66static inline struct fd fdget_raw(unsigned int fd)
67{
68 return __to_fd(__fdget_raw(fd));
69}
70
71static inline struct fd fdget_pos(int fd)
72{
73 return __to_fd(__fdget_pos(fd));
74}
75
76static inline void fdput_pos(struct fd f)
77{
78 if (f.flags & FDPUT_POS_UNLOCK)
79 __f_unlock_pos(f.file);
80 fdput(f);
81}
82
83extern int f_dupfd(unsigned int from, struct file *file, unsigned flags);
84extern int replace_fd(unsigned fd, struct file *file, unsigned flags);
85extern void set_close_on_exec(unsigned int fd, int flag);
86extern bool get_close_on_exec(unsigned int fd);
87extern int __get_unused_fd_flags(unsigned flags, unsigned long nofile);
88extern int get_unused_fd_flags(unsigned flags);
89extern void put_unused_fd(unsigned int fd);
90
91extern void fd_install(unsigned int fd, struct file *file);
92
93extern int __receive_fd(struct file *file, int __user *ufd,
94 unsigned int o_flags);
95
96extern int receive_fd(struct file *file, unsigned int o_flags);
97
98static inline int receive_fd_user(struct file *file, int __user *ufd,
99 unsigned int o_flags)
100{
101 if (ufd == NULL)
102 return -EFAULT;
103 return __receive_fd(file, ufd, o_flags);
104}
105int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags);
106
107extern void flush_delayed_fput(void);
108extern void __fput_sync(struct file *);
109
110extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
111
112#endif /* __LINUX_FILE_H */
113

source code of linux/include/linux/file.h