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#include <linux/cleanup.h>
14
15struct file;
16
17extern void fput(struct file *);
18
19struct file_operations;
20struct task_struct;
21struct vfsmount;
22struct dentry;
23struct inode;
24struct path;
25extern struct file *alloc_file_pseudo(struct inode *, struct vfsmount *,
26 const char *, int flags, const struct file_operations *);
27extern struct file *alloc_file_clone(struct file *, int flags,
28 const struct file_operations *);
29
30static inline void fput_light(struct file *file, int fput_needed)
31{
32 if (fput_needed)
33 fput(file);
34}
35
36struct fd {
37 struct file *file;
38 unsigned int flags;
39};
40#define FDPUT_FPUT 1
41#define FDPUT_POS_UNLOCK 2
42
43static inline void fdput(struct fd fd)
44{
45 if (fd.flags & FDPUT_FPUT)
46 fput(fd.file);
47}
48
49extern struct file *fget(unsigned int fd);
50extern struct file *fget_raw(unsigned int fd);
51extern struct file *fget_task(struct task_struct *task, unsigned int fd);
52extern unsigned long __fdget(unsigned int fd);
53extern unsigned long __fdget_raw(unsigned int fd);
54extern unsigned long __fdget_pos(unsigned int fd);
55extern void __f_unlock_pos(struct file *);
56
57static inline struct fd __to_fd(unsigned long v)
58{
59 return (struct fd){(struct file *)(v & ~3),v & 3};
60}
61
62static inline struct fd fdget(unsigned int fd)
63{
64 return __to_fd(v: __fdget(fd));
65}
66
67static inline struct fd fdget_raw(unsigned int fd)
68{
69 return __to_fd(v: __fdget_raw(fd));
70}
71
72static inline struct fd fdget_pos(int fd)
73{
74 return __to_fd(v: __fdget_pos(fd));
75}
76
77static inline void fdput_pos(struct fd f)
78{
79 if (f.flags & FDPUT_POS_UNLOCK)
80 __f_unlock_pos(f.file);
81 fdput(fd: f);
82}
83
84DEFINE_CLASS(fd, struct fd, fdput(_T), fdget(fd), int fd)
85
86extern int f_dupfd(unsigned int from, struct file *file, unsigned flags);
87extern int replace_fd(unsigned fd, struct file *file, unsigned flags);
88extern void set_close_on_exec(unsigned int fd, int flag);
89extern bool get_close_on_exec(unsigned int fd);
90extern int __get_unused_fd_flags(unsigned flags, unsigned long nofile);
91extern int get_unused_fd_flags(unsigned flags);
92extern void put_unused_fd(unsigned int fd);
93
94DEFINE_CLASS(get_unused_fd, int, if (_T >= 0) put_unused_fd(_T),
95 get_unused_fd_flags(flags), unsigned flags)
96
97extern void fd_install(unsigned int fd, struct file *file);
98
99extern int __receive_fd(struct file *file, int __user *ufd,
100 unsigned int o_flags);
101
102extern int receive_fd(struct file *file, unsigned int o_flags);
103
104static inline int receive_fd_user(struct file *file, int __user *ufd,
105 unsigned int o_flags)
106{
107 if (ufd == NULL)
108 return -EFAULT;
109 return __receive_fd(file, ufd, o_flags);
110}
111int receive_fd_replace(int new_fd, struct file *file, unsigned int o_flags);
112
113extern void flush_delayed_fput(void);
114extern void __fput_sync(struct file *);
115
116extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
117
118#endif /* __LINUX_FILE_H */
119

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