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