1 /* SPDX-License-Identifier: GPL-2.0 */
6 #include <linux/major.h>
7 #include <linux/termios.h>
8 #include <linux/workqueue.h>
9 #include <linux/tty_driver.h>
10 #include <linux/tty_ldisc.h>
11 #include <linux/mutex.h>
12 #include <linux/tty_flags.h>
13 #include <linux/seq_file.h>
14 #include <uapi/linux/tty.h>
15 #include <linux/rwsem.h>
16 #include <linux/llist.h>
20 * Lock subclasses for tty locks
22 * TTY_LOCK_NORMAL is for normal ttys and master ptys.
23 * TTY_LOCK_SLAVE is for slave ptys only.
25 * Lock subclasses are necessary for handling nested locking with pty pairs.
26 * tty locks which use nested locking:
28 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
29 * The stable lock order is master pty first, then slave pty.
30 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
31 * Subclassing this lock enables the slave pty to hold its
32 * termios_rwsem when claiming the master tty_buffer lock.
33 * tty_buffer lock - slave ptys can claim nested buffer lock when handling
34 * signal chars. The stable lock order is slave pty, then
44 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
45 * hardcoded at present.)
47 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
48 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
49 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
52 * This character is the same as _POSIX_VDISABLE: it cannot be used as
53 * a c_cc[] character, but indicates that a particular special character
54 * isn't in use (eg VINTR has no character etc)
56 #define __DISABLED_CHAR '\0'
60 struct tty_buffer *next;
61 struct llist_node free;
68 /* Data points here */
72 /* Values for .flags field of tty_buffer */
73 #define TTYB_NORMAL 1 /* buffer has no flags buffer */
75 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs)
77 return ((unsigned char *)b->data) + ofs;
80 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs)
82 return (char *)char_buf_ptr(b, ofs) + b->size;
86 struct tty_buffer *head; /* Queue head */
87 struct work_struct work;
90 struct tty_buffer sentinel;
91 struct llist_head free; /* Free queue head */
92 atomic_t mem_used; /* In-use buffers excluding free list */
94 struct tty_buffer *tail; /* Active buffer */
97 * When a break, frame error, or parity error happens, these codes are
98 * stuffed into the flags buffer.
104 #define TTY_OVERRUN 4
106 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
107 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
108 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
109 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
110 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
111 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
112 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
113 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
114 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
115 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
116 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
117 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
118 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
119 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
120 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
121 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
122 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
124 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
125 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
126 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
127 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
129 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
130 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
131 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
132 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
133 #define I_INPCK(tty) _I_FLAG((tty), INPCK)
134 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
135 #define I_INLCR(tty) _I_FLAG((tty), INLCR)
136 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
137 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
138 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
139 #define I_IXON(tty) _I_FLAG((tty), IXON)
140 #define I_IXANY(tty) _I_FLAG((tty), IXANY)
141 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
142 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
143 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
145 #define O_OPOST(tty) _O_FLAG((tty), OPOST)
146 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
147 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
148 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
149 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
150 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
151 #define O_OFILL(tty) _O_FLAG((tty), OFILL)
152 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
153 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
154 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
155 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
156 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
157 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
158 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
160 #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
161 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
162 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
163 #define C_CREAD(tty) _C_FLAG((tty), CREAD)
164 #define C_PARENB(tty) _C_FLAG((tty), PARENB)
165 #define C_PARODD(tty) _C_FLAG((tty), PARODD)
166 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
167 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
168 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
169 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
170 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR)
172 #define L_ISIG(tty) _L_FLAG((tty), ISIG)
173 #define L_ICANON(tty) _L_FLAG((tty), ICANON)
174 #define L_XCASE(tty) _L_FLAG((tty), XCASE)
175 #define L_ECHO(tty) _L_FLAG((tty), ECHO)
176 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
177 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
178 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
179 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
180 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
181 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
182 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
183 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
184 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
185 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
186 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
187 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
190 struct signal_struct;
193 * Port level information. Each device keeps its own port level information
194 * so provide a common structure for those ports wanting to use common support
197 * The tty port has a different lifetime to the tty so must be kept apart.
198 * In addition be careful as tty -> port mappings are valid for the life
199 * of the tty object but in many cases port -> tty mappings are valid only
200 * until a hangup so don't use the wrong path.
205 struct tty_port_operations {
206 /* Return 1 if the carrier is raised */
207 int (*carrier_raised)(struct tty_port *port);
208 /* Control the DTR line */
209 void (*dtr_rts)(struct tty_port *port, int raise);
210 /* Called when the last close completes or a hangup finishes
211 IFF the port was initialized. Do not use to free resources. Called
212 under the port mutex to serialize against activate/shutdowns */
213 void (*shutdown)(struct tty_port *port);
214 /* Called under the port mutex from tty_port_open, serialized using
216 /* FIXME: long term getting the tty argument *out* of this would be
218 int (*activate)(struct tty_port *port, struct tty_struct *tty);
219 /* Called on the final put of a port */
220 void (*destruct)(struct tty_port *port);
223 struct tty_port_client_operations {
224 int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t);
225 void (*write_wakeup)(struct tty_port *port);
228 extern const struct tty_port_client_operations tty_port_default_client_ops;
231 struct tty_bufhead buf; /* Locked internally */
232 struct tty_struct *tty; /* Back pointer */
233 struct tty_struct *itty; /* internal back ptr */
234 const struct tty_port_operations *ops; /* Port operations */
235 const struct tty_port_client_operations *client_ops; /* Port client operations */
236 spinlock_t lock; /* Lock protecting tty field */
237 int blocked_open; /* Waiting to open */
238 int count; /* Usage count */
239 wait_queue_head_t open_wait; /* Open waiters */
240 wait_queue_head_t delta_msr_wait; /* Modem status change */
241 unsigned long flags; /* User TTY flags ASYNC_ */
242 unsigned long iflags; /* Internal flags TTY_PORT_ */
243 unsigned char console:1; /* port is a console */
244 struct mutex mutex; /* Locking */
245 struct mutex buf_mutex; /* Buffer alloc lock */
246 unsigned char *xmit_buf; /* Optional buffer */
247 unsigned int close_delay; /* Close port delay */
248 unsigned int closing_wait; /* Delay for output */
249 int drain_delay; /* Set to zero if no pure time
250 based drain is needed else
251 set to size of fifo */
252 struct kref kref; /* Ref counter */
256 /* tty_port::iflags bits -- use atomic bit ops */
257 #define TTY_PORT_INITIALIZED 0 /* device is initialized */
258 #define TTY_PORT_SUSPENDED 1 /* device is suspended */
259 #define TTY_PORT_ACTIVE 2 /* device is open */
262 * uart drivers: use the uart_port::status field and the UPSTAT_* defines
263 * for s/w-based flow control steering and carrier detection status
265 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */
266 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */
267 #define TTY_PORT_KOPENED 5 /* device exclusively opened by
271 * Where all of the state associated with a tty is kept while the tty
272 * is open. Since the termios state should be kept even if the tty
273 * has been closed --- for things like the baud rate, etc --- it is
274 * not stored here, but rather a pointer to the real state is stored
275 * here. Possible the winsize structure should have the same
276 * treatment, but (1) the default 80x24 is usually right and (2) it's
277 * most often used by a windowing system, which will set the correct
278 * size each time the window is created or resized anyway.
282 struct tty_operations;
288 struct tty_driver *driver;
289 const struct tty_operations *ops;
292 /* Protects ldisc changes: Lock tty not pty */
293 struct ld_semaphore ldisc_sem;
294 struct tty_ldisc *ldisc;
296 struct mutex atomic_write_lock;
297 struct mutex legacy_mutex;
298 struct mutex throttle_mutex;
299 struct rw_semaphore termios_rwsem;
300 struct mutex winsize_mutex;
301 spinlock_t ctrl_lock;
302 spinlock_t flow_lock;
303 /* Termios values are protected by the termios rwsem */
304 struct ktermios termios, termios_locked;
306 struct pid *pgrp; /* Protected by ctrl lock */
308 * Writes protected by both ctrl lock and legacy mutex, readers must use
309 * at least one of them.
314 struct winsize winsize; /* winsize_mutex */
315 unsigned long stopped:1, /* flow_lock */
317 unused:BITS_PER_LONG - 2;
319 unsigned long ctrl_status:8, /* ctrl_lock */
321 unused_ctrl:BITS_PER_LONG - 9;
322 unsigned int receive_room; /* Bytes free for queue */
325 struct tty_struct *link;
326 struct fasync_struct *fasync;
327 wait_queue_head_t write_wait;
328 wait_queue_head_t read_wait;
329 struct work_struct hangup_work;
332 spinlock_t files_lock; /* protects tty_files list */
333 struct list_head tty_files;
335 #define N_TTY_BUF_SIZE 4096
338 unsigned char *write_buf;
340 /* If the tty has a pending do_SAK, queue it here - akpm */
341 struct work_struct SAK_work;
342 struct tty_port *port;
343 } __randomize_layout;
345 /* Each of a tty's open files has private_data pointing to tty_file_private */
346 struct tty_file_private {
347 struct tty_struct *tty;
349 struct list_head list;
352 /* tty magic number */
353 #define TTY_MAGIC 0x5401
356 * These bits are used in the flags field of the tty structure.
358 * So that interrupts won't be able to mess up the queues,
359 * copy_to_cooked must be atomic with respect to itself, as must
360 * tty->write. Thus, you must use the inline functions set_bit() and
361 * clear_bit() to make things atomic.
363 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
364 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
365 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
366 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
367 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
368 #define TTY_LDISC_OPEN 11 /* Line discipline is open */
369 #define TTY_PTY_LOCK 16 /* pty private */
370 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
371 #define TTY_HUPPED 18 /* Post driver->hangup() */
372 #define TTY_HUPPING 19 /* Hangup in progress */
373 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */
374 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */
376 /* Values for tty->flow_change */
377 #define TTY_THROTTLE_SAFE 1
378 #define TTY_UNTHROTTLE_SAFE 2
380 static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
382 tty->flow_change = val;
385 static inline void tty_set_flow_change(struct tty_struct *tty, int val)
387 tty->flow_change = val;
391 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
393 return file->f_flags & O_NONBLOCK ||
394 test_bit(TTY_LDISC_CHANGING, &tty->flags);
397 static inline bool tty_io_error(struct tty_struct *tty)
399 return test_bit(TTY_IO_ERROR, &tty->flags);
402 static inline bool tty_throttled(struct tty_struct *tty)
404 return test_bit(TTY_THROTTLED, &tty->flags);
408 extern void tty_kref_put(struct tty_struct *tty);
409 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
410 extern void tty_vhangup_self(void);
411 extern void disassociate_ctty(int priv);
412 extern dev_t tty_devnum(struct tty_struct *tty);
413 extern void proc_clear_tty(struct task_struct *p);
414 extern struct tty_struct *get_current_tty(void);
416 extern int __init tty_init(void);
417 extern const char *tty_name(const struct tty_struct *tty);
418 extern struct tty_struct *tty_kopen_exclusive(dev_t device);
419 extern struct tty_struct *tty_kopen_shared(dev_t device);
420 extern void tty_kclose(struct tty_struct *tty);
421 extern int tty_dev_name_to_number(const char *name, dev_t *number);
422 extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
423 extern void tty_ldisc_unlock(struct tty_struct *tty);
424 extern ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *);
425 extern struct file *tty_release_redirect(struct tty_struct *tty);
427 static inline void tty_kref_put(struct tty_struct *tty)
429 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
431 static inline void tty_vhangup_self(void)
433 static inline void disassociate_ctty(int priv)
435 static inline dev_t tty_devnum(struct tty_struct *tty)
437 static inline void proc_clear_tty(struct task_struct *p)
439 static inline struct tty_struct *get_current_tty(void)
442 static inline int __init tty_init(void)
444 static inline const char *tty_name(const struct tty_struct *tty)
446 static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
447 { return ERR_PTR(-ENODEV); }
448 static inline void tty_kclose(struct tty_struct *tty)
450 static inline int tty_dev_name_to_number(const char *name, dev_t *number)
451 { return -ENOTSUPP; }
454 extern struct ktermios tty_std_termios;
456 extern int vcs_init(void);
458 extern struct class *tty_class;
461 * tty_kref_get - get a tty reference
464 * Return a new reference to a tty object. The caller must hold
465 * sufficient locks/counts to ensure that their existing reference cannot
469 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
472 kref_get(&tty->kref);
476 extern const char *tty_driver_name(const struct tty_struct *tty);
477 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
478 extern int __tty_check_change(struct tty_struct *tty, int sig);
479 extern int tty_check_change(struct tty_struct *tty);
480 extern void __stop_tty(struct tty_struct *tty);
481 extern void stop_tty(struct tty_struct *tty);
482 extern void __start_tty(struct tty_struct *tty);
483 extern void start_tty(struct tty_struct *tty);
484 extern int tty_register_driver(struct tty_driver *driver);
485 extern int tty_unregister_driver(struct tty_driver *driver);
486 extern struct device *tty_register_device(struct tty_driver *driver,
487 unsigned index, struct device *dev);
488 extern struct device *tty_register_device_attr(struct tty_driver *driver,
489 unsigned index, struct device *device,
491 const struct attribute_group **attr_grp);
492 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
493 extern void tty_write_message(struct tty_struct *tty, char *msg);
494 extern int tty_send_xchar(struct tty_struct *tty, char ch);
495 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
496 extern int tty_chars_in_buffer(struct tty_struct *tty);
497 extern int tty_write_room(struct tty_struct *tty);
498 extern void tty_driver_flush_buffer(struct tty_struct *tty);
499 extern void tty_throttle(struct tty_struct *tty);
500 extern void tty_unthrottle(struct tty_struct *tty);
501 extern int tty_throttle_safe(struct tty_struct *tty);
502 extern int tty_unthrottle_safe(struct tty_struct *tty);
503 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
504 extern int tty_get_icount(struct tty_struct *tty,
505 struct serial_icounter_struct *icount);
506 extern int is_current_pgrp_orphaned(void);
507 extern void tty_hangup(struct tty_struct *tty);
508 extern void tty_vhangup(struct tty_struct *tty);
509 extern void tty_vhangup_session(struct tty_struct *tty);
510 extern int tty_hung_up_p(struct file *filp);
511 extern void do_SAK(struct tty_struct *tty);
512 extern void __do_SAK(struct tty_struct *tty);
513 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
514 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
515 extern void session_clear_tty(struct pid *session);
516 extern void no_tty(void);
517 extern void tty_buffer_free_all(struct tty_port *port);
518 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
519 extern void tty_buffer_init(struct tty_port *port);
520 extern void tty_buffer_set_lock_subclass(struct tty_port *port);
521 extern bool tty_buffer_restart_work(struct tty_port *port);
522 extern bool tty_buffer_cancel_work(struct tty_port *port);
523 extern void tty_buffer_flush_work(struct tty_port *port);
524 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
525 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
526 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
527 speed_t ibaud, speed_t obaud);
528 extern void tty_encode_baud_rate(struct tty_struct *tty,
529 speed_t ibaud, speed_t obaud);
532 * tty_get_baud_rate - get tty bit rates
535 * Returns the baud rate as an integer for this terminal. The
536 * termios lock must be held by the caller and the terminal bit
537 * flags may be updated.
541 static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
543 return tty_termios_baud_rate(&tty->termios);
546 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
547 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
548 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
550 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
551 extern void tty_ldisc_deref(struct tty_ldisc *);
552 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
553 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset);
554 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc);
555 extern const struct seq_operations tty_ldiscs_seq_ops;
557 extern void tty_wakeup(struct tty_struct *tty);
558 extern void tty_ldisc_flush(struct tty_struct *tty);
560 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
561 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
562 unsigned int cmd, unsigned long arg);
563 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty,
564 struct file *file, unsigned int cmd, unsigned long arg);
565 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
566 extern void tty_default_fops(struct file_operations *fops);
567 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
568 extern int tty_alloc_file(struct file *file);
569 extern void tty_add_file(struct tty_struct *tty, struct file *file);
570 extern void tty_free_file(struct file *file);
571 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
572 extern void tty_release_struct(struct tty_struct *tty, int idx);
573 extern int tty_release(struct inode *inode, struct file *filp);
574 extern void tty_init_termios(struct tty_struct *tty);
575 extern void tty_save_termios(struct tty_struct *tty);
576 extern int tty_standard_install(struct tty_driver *driver,
577 struct tty_struct *tty);
579 extern struct mutex tty_mutex;
581 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
583 extern void tty_port_init(struct tty_port *port);
584 extern void tty_port_link_device(struct tty_port *port,
585 struct tty_driver *driver, unsigned index);
586 extern struct device *tty_port_register_device(struct tty_port *port,
587 struct tty_driver *driver, unsigned index,
588 struct device *device);
589 extern struct device *tty_port_register_device_attr(struct tty_port *port,
590 struct tty_driver *driver, unsigned index,
591 struct device *device, void *drvdata,
592 const struct attribute_group **attr_grp);
593 extern struct device *tty_port_register_device_serdev(struct tty_port *port,
594 struct tty_driver *driver, unsigned index,
595 struct device *device);
596 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
597 struct tty_driver *driver, unsigned index,
598 struct device *device, void *drvdata,
599 const struct attribute_group **attr_grp);
600 extern void tty_port_unregister_device(struct tty_port *port,
601 struct tty_driver *driver, unsigned index);
602 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
603 extern void tty_port_free_xmit_buf(struct tty_port *port);
604 extern void tty_port_destroy(struct tty_port *port);
605 extern void tty_port_put(struct tty_port *port);
607 static inline struct tty_port *tty_port_get(struct tty_port *port)
609 if (port && kref_get_unless_zero(&port->kref))
614 /* If the cts flow control is enabled, return true. */
615 static inline bool tty_port_cts_enabled(const struct tty_port *port)
617 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags);
620 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val)
622 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val);
625 static inline bool tty_port_active(const struct tty_port *port)
627 return test_bit(TTY_PORT_ACTIVE, &port->iflags);
630 static inline void tty_port_set_active(struct tty_port *port, bool val)
632 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val);
635 static inline bool tty_port_check_carrier(const struct tty_port *port)
637 return test_bit(TTY_PORT_CHECK_CD, &port->iflags);
640 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
642 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val);
645 static inline bool tty_port_suspended(const struct tty_port *port)
647 return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
650 static inline void tty_port_set_suspended(struct tty_port *port, bool val)
652 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val);
655 static inline bool tty_port_initialized(const struct tty_port *port)
657 return test_bit(TTY_PORT_INITIALIZED, &port->iflags);
660 static inline void tty_port_set_initialized(struct tty_port *port, bool val)
662 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val);
665 static inline bool tty_port_kopened(const struct tty_port *port)
667 return test_bit(TTY_PORT_KOPENED, &port->iflags);
670 static inline void tty_port_set_kopened(struct tty_port *port, bool val)
672 assign_bit(TTY_PORT_KOPENED, &port->iflags, val);
675 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
676 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
677 extern int tty_port_carrier_raised(struct tty_port *port);
678 extern void tty_port_raise_dtr_rts(struct tty_port *port);
679 extern void tty_port_lower_dtr_rts(struct tty_port *port);
680 extern void tty_port_hangup(struct tty_port *port);
681 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
682 extern void tty_port_tty_wakeup(struct tty_port *port);
683 extern int tty_port_block_til_ready(struct tty_port *port,
684 struct tty_struct *tty, struct file *filp);
685 extern int tty_port_close_start(struct tty_port *port,
686 struct tty_struct *tty, struct file *filp);
687 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
688 extern void tty_port_close(struct tty_port *port,
689 struct tty_struct *tty, struct file *filp);
690 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
691 struct tty_struct *tty);
692 extern int tty_port_open(struct tty_port *port,
693 struct tty_struct *tty, struct file *filp);
694 static inline int tty_port_users(struct tty_port *port)
696 return port->count + port->blocked_open;
699 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
700 extern int tty_unregister_ldisc(int disc);
701 extern int tty_set_ldisc(struct tty_struct *tty, int disc);
702 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
703 extern void tty_ldisc_release(struct tty_struct *tty);
704 extern int __must_check tty_ldisc_init(struct tty_struct *tty);
705 extern void tty_ldisc_deinit(struct tty_struct *tty);
706 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
708 extern void tty_sysctl_init(void);
711 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
713 extern void __init n_tty_init(void);
715 static inline void n_tty_init(void) { }
720 extern void tty_audit_add_data(struct tty_struct *tty, const void *data,
722 extern void tty_audit_exit(void);
723 extern void tty_audit_fork(struct signal_struct *sig);
724 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
725 extern int tty_audit_push(void);
727 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data,
731 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
734 static inline void tty_audit_exit(void)
737 static inline void tty_audit_fork(struct signal_struct *sig)
740 static inline int tty_audit_push(void)
747 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
748 unsigned int cmd, unsigned long arg);
752 extern int vt_ioctl(struct tty_struct *tty,
753 unsigned int cmd, unsigned long arg);
755 extern long vt_compat_ioctl(struct tty_struct *tty,
756 unsigned int cmd, unsigned long arg);
759 /* functions for preparation of BKL removal */
760 extern void tty_lock(struct tty_struct *tty);
761 extern int tty_lock_interruptible(struct tty_struct *tty);
762 extern void tty_unlock(struct tty_struct *tty);
763 extern void tty_lock_slave(struct tty_struct *tty);
764 extern void tty_unlock_slave(struct tty_struct *tty);
765 extern void tty_set_lock_subclass(struct tty_struct *tty);
767 #ifdef CONFIG_PROC_FS
768 extern void proc_tty_register_driver(struct tty_driver *);
769 extern void proc_tty_unregister_driver(struct tty_driver *);
771 static inline void proc_tty_register_driver(struct tty_driver *d) {}
772 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
775 #define tty_msg(fn, tty, f, ...) \
776 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__)
778 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__)
779 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__)
780 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__)
781 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__)
782 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__)
784 #define tty_info_ratelimited(tty, f, ...) \
785 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__)