include/linux/file.h

   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
  13 struct file;
  14
  15 extern void fput(struct file *);
  16
  17 struct file_operations;
  18 struct vfsmount;
  19 struct dentry;
  20 struct path;
  21 extern struct file *alloc_file(const struct path *, fmode_t mode,
  22         const struct file_operations *fop);
  23
  24 static inline void fput_light(struct file *file, int fput_needed)
  25 {
  26         if (fput_needed)
  27                 fput(file);
  28 }
  29
  30 struct fd {
  31         struct file *file;
  32         unsigned int flags;
  33 };
  34 #define FDPUT_FPUT       1
  35 #define FDPUT_POS_UNLOCK 2
  36
  37 static inline void fdput(struct fd fd)
  38 {
  39         if (fd.flags & FDPUT_FPUT)
  40                 fput(fd.file);
  41 }
  42
  43 extern struct file *fget(unsigned int fd);
  44 extern struct file *fget_raw(unsigned int fd);
  45 extern unsigned long __fdget(unsigned int fd);
  46 extern unsigned long __fdget_raw(unsigned int fd);
  47 extern unsigned long __fdget_pos(unsigned int fd);
  48 extern void __f_unlock_pos(struct file *);
  49
  50 static inline struct fd __to_fd(unsigned long v)
  51 {
  52         return (struct fd){(struct file *)(v & ~3),v & 3};
  53 }
  54
  55 static inline struct fd fdget(unsigned int fd)
  56 {
  57         return __to_fd(__fdget(fd));
  58 }
  59
  60 static inline struct fd fdget_raw(unsigned int fd)
  61 {
  62         return __to_fd(__fdget_raw(fd));
  63 }
  64
  65 static inline struct fd fdget_pos(int fd)
  66 {
  67         return __to_fd(__fdget_pos(fd));
  68 }
  69
  70 static inline void fdput_pos(struct fd f)
  71 {
  72         if (f.flags & FDPUT_POS_UNLOCK)
  73                 __f_unlock_pos(f.file);
  74         fdput(f);
  75 }
  76
  77 extern int f_dupfd(unsigned int from, struct file *file, unsigned flags);
  78 extern int replace_fd(unsigned fd, struct file *file, unsigned flags);
  79 extern void set_close_on_exec(unsigned int fd, int flag);
  80 extern bool get_close_on_exec(unsigned int fd);
  81 extern void put_filp(struct file *);
  82 extern int get_unused_fd_flags(unsigned flags);
  83 extern void put_unused_fd(unsigned int fd);
  84
  85 extern void fd_install(unsigned int fd, struct file *file);
  86
  87 extern void flush_delayed_fput(void);
  88 extern void __fput_sync(struct file *);
  89
  90 #endif /* __LINUX_FILE_H */