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 static inline void __tty_set_flow_change(struct tty_struct *tty, 51 enum tty_flow_change val) 52 { 53 tty->flow_change = val; 54 } 55 56 static inline void tty_set_flow_change(struct tty_struct *tty, 57 enum tty_flow_change val) 58 { 59 tty->flow_change = val; 60 smp_mb(); 61 } 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 126