struct file

include/linux/fs.h

struct file {

    /*
     * fu_list becomes invalid after file_free is called and queued via
     * fu_rcuhead for RCU freeing
     */
    union {
        struct list_head    fu_list;
        struct rcu_head     fu_rcuhead;
    } f_u;
    struct path        f_path;
#define f_dentry    f_path.dentry
#define f_vfsmnt    f_path.mnt
    const struct file_operations    *f_op;
    spinlock_t        f_lock;  /* f_ep_links, f_flags, no IRQ */
#ifdef CONFIG_SMP
    int            f_sb_list_cpu;
#endif
    atomic_long_t        f_count;
    unsigned int         f_flags;
    fmode_t            f_mode;
    loff_t            f_pos;
    struct fown_struct    f_owner;
    const struct cred    *f_cred;
    struct file_ra_state    f_ra;

    u64            f_version;
#ifdef CONFIG_SECURITY
    void            *f_security;
#endif
    /* needed for tty driver, and maybe others */
    void            *private_data;

#ifdef CONFIG_EPOLL
    /* Used by fs/eventpoll.c to link all the hooks to this file */
    struct list_head    f_ep_links;
#endif /* #ifdef CONFIG_EPOLL */
    struct address_space    *f_mapping;
#ifdef CONFIG_DEBUG_WRITECOUNT
    unsigned long f_mnt_write_state;
#endif
};