Line data    Source code

       1              : /* SPDX-License-Identifier: GPL-2.0 */
       2              : /*
       3              :  * TTY core internal functions
       4              :  */
       5              : 
       6              : #ifndef _TTY_INTERNAL_H
       7              : #define _TTY_INTERNAL_H
       8              : 
       9              : #define tty_msg(fn, tty, f, ...) \
      10              :         fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__)
      11              : 
      12              : #define tty_debug(tty, f, ...)  tty_msg(pr_debug, tty, f, ##__VA_ARGS__)
      13              : #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__)
      14              : #define tty_warn(tty, f, ...)   tty_msg(pr_warn, tty, f, ##__VA_ARGS__)
      15              : #define tty_err(tty, f, ...)    tty_msg(pr_err, tty, f, ##__VA_ARGS__)
      16              : 
      17              : #define tty_info_ratelimited(tty, f, ...) \
      18              :                 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__)
      19              : 
      20              : /*
      21              :  * Lock subclasses for tty locks
      22              :  *
      23              :  * TTY_LOCK_NORMAL is for normal ttys and master ptys.
      24              :  * TTY_LOCK_SLAVE is for slave ptys only.
      25              :  *
      26              :  * Lock subclasses are necessary for handling nested locking with pty pairs.
      27              :  * tty locks which use nested locking:
      28              :  *
      29              :  * legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
      30              :  *                The stable lock order is master pty first, then slave pty.
      31              :  * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
      32              :  *                 Subclassing this lock enables the slave pty to hold its
      33              :  *                 termios_rwsem when claiming the master tty_buffer lock.
      34              :  * tty_buffer lock - slave ptys can claim nested buffer lock when handling
      35              :  *                   signal chars. The stable lock order is slave pty, then
      36              :  *                   master.
      37              :  */
      38              : enum {
      39              :         TTY_LOCK_NORMAL = 0,
      40              :         TTY_LOCK_SLAVE,
      41              : };
      42              : 
      43              : /* Values for tty->flow_change */
      44              : enum tty_flow_change {
      45              :         TTY_FLOW_NO_CHANGE,
      46              :         TTY_THROTTLE_SAFE,
      47              :         TTY_UNTHROTTLE_SAFE,
      48              : };
      49              : 
      50            1 : static inline void __tty_set_flow_change(struct tty_struct *tty,
      51              :                                          enum tty_flow_change val)
      52              : {
      53            1 :         tty->flow_change = val;
      54            1 : }
      55              : 
      56            1 : static inline void tty_set_flow_change(struct tty_struct *tty,
      57              :                                        enum tty_flow_change val)
      58              : {
      59            1 :         tty->flow_change = val;
      60            1 :         smp_mb();
      61            1 : }
      62              : 
      63              : int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
      64              : void tty_ldisc_unlock(struct tty_struct *tty);
      65              : 
      66              : int __tty_check_change(struct tty_struct *tty, int sig);
      67              : int tty_check_change(struct tty_struct *tty);
      68              : void __stop_tty(struct tty_struct *tty);
      69              : void __start_tty(struct tty_struct *tty);
      70              : void tty_write_unlock(struct tty_struct *tty);
      71              : int tty_write_lock(struct tty_struct *tty, bool ndelay);
      72              : void tty_vhangup_session(struct tty_struct *tty);
      73              : void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
      74              : int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
      75              : void session_clear_tty(struct pid *session);
      76              : void tty_buffer_free_all(struct tty_port *port);
      77              : void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
      78              : void tty_buffer_init(struct tty_port *port);
      79              : void tty_buffer_set_lock_subclass(struct tty_port *port);
      80              : bool tty_buffer_restart_work(struct tty_port *port);
      81              : bool tty_buffer_cancel_work(struct tty_port *port);
      82              : void tty_buffer_flush_work(struct tty_port *port);
      83              : speed_t tty_termios_input_baud_rate(const struct ktermios *termios);
      84              : void tty_ldisc_hangup(struct tty_struct *tty, bool reset);
      85              : int tty_ldisc_reinit(struct tty_struct *tty, int disc);
      86              : long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
      87              : long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty,
      88              :                        struct file *file, unsigned int cmd, unsigned long arg);
      89              : void tty_default_fops(struct file_operations *fops);
      90              : struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
      91              : int tty_alloc_file(struct file *file);
      92              : void tty_add_file(struct tty_struct *tty, struct file *file);
      93              : void tty_free_file(struct file *file);
      94              : int tty_release(struct inode *inode, struct file *filp);
      95              : 
      96              : #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
      97              : 
      98              : int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
      99              : void tty_ldisc_release(struct tty_struct *tty);
     100              : int __must_check tty_ldisc_init(struct tty_struct *tty);
     101              : void tty_ldisc_deinit(struct tty_struct *tty);
     102              : 
     103              : extern int tty_ldisc_autoload;
     104              : 
     105              : /* tty_audit.c */
     106              : #ifdef CONFIG_AUDIT
     107              : void tty_audit_add_data(const struct tty_struct *tty, const void *data,
     108              :                         size_t size);
     109              : void tty_audit_tiocsti(const struct tty_struct *tty, u8 ch);
     110              : #else
     111              : static inline void tty_audit_add_data(const struct tty_struct *tty,
     112              :                                       const void *data, size_t size)
     113              : {
     114              : }
     115              : static inline void tty_audit_tiocsti(const struct tty_struct *tty, u8 ch)
     116              : {
     117              : }
     118              : #endif
     119              : 
     120              : ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *);
     121              : 
     122              : int tty_insert_flip_string_and_push_buffer(struct tty_port *port,
     123              :                                            const u8 *chars, size_t cnt);
     124              : 
     125              : #endif