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