file_operations结构体

使用：

struct file_operations fops = {
    .owner = THIS_MODULE,
    .read = myread,
    //当然还有其他的就不一一列举了
};

通过ta file_operations：

 struct file_operations {
     struct module *owner;
     loff_t (*llseek) (struct file *, loff_t, int);
     ssize_t (*read) (struct file *, char __user *, size_t, loff_t *);
     ssize_t (*write) (struct file *, const char __user *, size_t, loff_t *);
     ssize_t (*read_iter) (struct kiocb *, struct iov_iter *);
     ssize_t (*write_iter) (struct kiocb *, struct iov_iter *);
     int (*iterate) (struct file *, struct dir_context *);
     int (*iterate_shared) (struct file *, struct dir_context *);
     unsigned int (*poll) (struct file *, struct poll_table_struct *);
     long (*unlocked_ioctl) (struct file *, unsigned int, unsigned long);
     long (*compat_ioctl) (struct file *, unsigned int, unsigned long);
     int (*mmap) (struct file *, struct vm_area_struct *);
     int (*open) (struct inode *, struct file *);
     int (*flush) (struct file *, fl_owner_t id);
     int (*release) (struct inode *, struct file *);
     int (*fsync) (struct file *, loff_t, loff_t, int datasync);
     int (*fasync) (int, struct file *, int);
     int (*lock) (struct file *, int, struct file_lock *);
     ssize_t (*sendpage) (struct file *, struct page *, int, size_t, loff_t *, int);
     unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long,unsigned long);
     int (*check_flags)(int);
     int (*flock) (struct file *, int, struct file_lock *);
     ssize_t (*splice_write)(struct pipe_inode_info *, struct file *, loff_t *, size_t, unsignedint);
     ssize_t (*splice_read)(struct file *, loff_t *, struct pipe_inode_info *, size_t, unsigned int);
     int (*setlease)(struct file *, long, struct file_lock **, void **);
     long (*fallocate)(struct file *file, int mode, loff_t offset,loff_t len);
     void (*show_fdinfo)(struct seq_file *m, struct file *f);
 #ifndef CONFIG_MMU
     unsigned (*mmap_capabilities)(struct file *);
 #endif
     ssize_t (*copy_file_range)(struct file *, loff_t, struct file *,loff_t, size_t, unsigned int);
     int (*clone_file_range)(struct file *, loff_t, struct file *, loff_t,u64);
     ssize_t (*dedupe_file_range)(struct file *, u64, u64, struct file *,u64);
 };