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