xref: /linux-6.15/include/linux/tty.h (revision dfc34940)
1 #ifndef _LINUX_TTY_H
2 #define _LINUX_TTY_H
3 
4 /*
5  * 'tty.h' defines some structures used by tty_io.c and some defines.
6  */
7 
8 #ifdef __KERNEL__
9 #include <linux/fs.h>
10 #include <linux/major.h>
11 #include <linux/termios.h>
12 #include <linux/workqueue.h>
13 #include <linux/tty_driver.h>
14 #include <linux/tty_ldisc.h>
15 #include <linux/mutex.h>
16 
17 #include <asm/system.h>
18 
19 
20 /*
21  * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
22  * hardcoded at present.)
23  */
24 #define NR_UNIX98_PTY_DEFAULT	4096      /* Default maximum for Unix98 ptys */
25 #define NR_UNIX98_PTY_MAX	(1 << MINORBITS) /* Absolute limit */
26 #define NR_LDISCS		20
27 
28 /* line disciplines */
29 #define N_TTY		0
30 #define N_SLIP		1
31 #define N_MOUSE		2
32 #define N_PPP		3
33 #define N_STRIP		4
34 #define N_AX25		5
35 #define N_X25		6	/* X.25 async */
36 #define N_6PACK		7
37 #define N_MASC		8	/* Reserved for Mobitex module <[email protected]> */
38 #define N_R3964		9	/* Reserved for Simatic R3964 module */
39 #define N_PROFIBUS_FDL	10	/* Reserved for Profibus */
40 #define N_IRDA		11	/* Linux IrDa - http://irda.sourceforge.net/ */
41 #define N_SMSBLOCK	12	/* SMS block mode - for talking to GSM data */
42 				/* cards about SMS messages */
43 #define N_HDLC		13	/* synchronous HDLC */
44 #define N_SYNC_PPP	14	/* synchronous PPP */
45 #define N_HCI		15	/* Bluetooth HCI UART */
46 #define N_GIGASET_M101	16	/* Siemens Gigaset M101 serial DECT adapter */
47 #define N_SLCAN		17	/* Serial / USB serial CAN Adaptors */
48 #define N_PPS		18	/* Pulse per Second */
49 
50 #define N_V253		19	/* Codec control over voice modem */
51 
52 /*
53  * This character is the same as _POSIX_VDISABLE: it cannot be used as
54  * a c_cc[] character, but indicates that a particular special character
55  * isn't in use (eg VINTR has no character etc)
56  */
57 #define __DISABLED_CHAR '\0'
58 
59 struct tty_buffer {
60 	struct tty_buffer *next;
61 	char *char_buf_ptr;
62 	unsigned char *flag_buf_ptr;
63 	int used;
64 	int size;
65 	int commit;
66 	int read;
67 	/* Data points here */
68 	unsigned long data[0];
69 };
70 
71 struct tty_bufhead {
72 	struct delayed_work work;
73 	spinlock_t lock;
74 	struct tty_buffer *head;	/* Queue head */
75 	struct tty_buffer *tail;	/* Active buffer */
76 	struct tty_buffer *free;	/* Free queue head */
77 	int memory_used;		/* Buffer space used excluding
78 								free queue */
79 };
80 /*
81  * When a break, frame error, or parity error happens, these codes are
82  * stuffed into the flags buffer.
83  */
84 #define TTY_NORMAL	0
85 #define TTY_BREAK	1
86 #define TTY_FRAME	2
87 #define TTY_PARITY	3
88 #define TTY_OVERRUN	4
89 
90 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
91 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
92 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
93 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
94 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
95 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
96 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
97 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
98 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
99 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
100 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
101 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
102 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
103 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
104 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
105 #define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
106 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
107 
108 #define _I_FLAG(tty, f)	((tty)->termios->c_iflag & (f))
109 #define _O_FLAG(tty, f)	((tty)->termios->c_oflag & (f))
110 #define _C_FLAG(tty, f)	((tty)->termios->c_cflag & (f))
111 #define _L_FLAG(tty, f)	((tty)->termios->c_lflag & (f))
112 
113 #define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
114 #define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
115 #define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
116 #define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
117 #define I_INPCK(tty)	_I_FLAG((tty), INPCK)
118 #define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
119 #define I_INLCR(tty)	_I_FLAG((tty), INLCR)
120 #define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
121 #define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
122 #define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
123 #define I_IXON(tty)	_I_FLAG((tty), IXON)
124 #define I_IXANY(tty)	_I_FLAG((tty), IXANY)
125 #define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
126 #define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
127 #define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
128 
129 #define O_OPOST(tty)	_O_FLAG((tty), OPOST)
130 #define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
131 #define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
132 #define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
133 #define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
134 #define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
135 #define O_OFILL(tty)	_O_FLAG((tty), OFILL)
136 #define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
137 #define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
138 #define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
139 #define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
140 #define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
141 #define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
142 #define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
143 
144 #define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
145 #define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
146 #define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
147 #define C_CREAD(tty)	_C_FLAG((tty), CREAD)
148 #define C_PARENB(tty)	_C_FLAG((tty), PARENB)
149 #define C_PARODD(tty)	_C_FLAG((tty), PARODD)
150 #define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
151 #define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
152 #define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
153 #define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
154 
155 #define L_ISIG(tty)	_L_FLAG((tty), ISIG)
156 #define L_ICANON(tty)	_L_FLAG((tty), ICANON)
157 #define L_XCASE(tty)	_L_FLAG((tty), XCASE)
158 #define L_ECHO(tty)	_L_FLAG((tty), ECHO)
159 #define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
160 #define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
161 #define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
162 #define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
163 #define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
164 #define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
165 #define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
166 #define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
167 #define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
168 #define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
169 #define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
170 
171 struct device;
172 struct signal_struct;
173 
174 /*
175  * Port level information. Each device keeps its own port level information
176  * so provide a common structure for those ports wanting to use common support
177  * routines.
178  *
179  * The tty port has a different lifetime to the tty so must be kept apart.
180  * In addition be careful as tty -> port mappings are valid for the life
181  * of the tty object but in many cases port -> tty mappings are valid only
182  * until a hangup so don't use the wrong path.
183  */
184 
185 struct tty_port;
186 
187 struct tty_port_operations {
188 	/* Return 1 if the carrier is raised */
189 	int (*carrier_raised)(struct tty_port *port);
190 	/* Control the DTR line */
191 	void (*dtr_rts)(struct tty_port *port, int raise);
192 	/* Called when the last close completes or a hangup finishes
193 	   IFF the port was initialized. Do not use to free resources */
194 	void (*shutdown)(struct tty_port *port);
195 	void (*drop)(struct tty_port *port);
196 };
197 
198 struct tty_port {
199 	struct tty_struct	*tty;		/* Back pointer */
200 	const struct tty_port_operations *ops;	/* Port operations */
201 	spinlock_t		lock;		/* Lock protecting tty field */
202 	int			blocked_open;	/* Waiting to open */
203 	int			count;		/* Usage count */
204 	wait_queue_head_t	open_wait;	/* Open waiters */
205 	wait_queue_head_t	close_wait;	/* Close waiters */
206 	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
207 	unsigned long		flags;		/* TTY flags ASY_*/
208 	struct mutex		mutex;		/* Locking */
209 	unsigned char		*xmit_buf;	/* Optional buffer */
210 	unsigned int		close_delay;	/* Close port delay */
211 	unsigned int		closing_wait;	/* Delay for output */
212 	int			drain_delay;	/* Set to zero if no pure time
213 						   based drain is needed else
214 						   set to size of fifo */
215 };
216 
217 /*
218  * Where all of the state associated with a tty is kept while the tty
219  * is open.  Since the termios state should be kept even if the tty
220  * has been closed --- for things like the baud rate, etc --- it is
221  * not stored here, but rather a pointer to the real state is stored
222  * here.  Possible the winsize structure should have the same
223  * treatment, but (1) the default 80x24 is usually right and (2) it's
224  * most often used by a windowing system, which will set the correct
225  * size each time the window is created or resized anyway.
226  * 						- TYT, 9/14/92
227  */
228 
229 struct tty_operations;
230 
231 struct tty_struct {
232 	int	magic;
233 	struct kref kref;
234 	struct tty_driver *driver;
235 	const struct tty_operations *ops;
236 	int index;
237 
238 	/* Protects ldisc changes: Lock tty not pty */
239 	struct mutex ldisc_mutex;
240 	struct tty_ldisc *ldisc;
241 
242 	struct mutex termios_mutex;
243 	spinlock_t ctrl_lock;
244 	/* Termios values are protected by the termios mutex */
245 	struct ktermios *termios, *termios_locked;
246 	struct termiox *termiox;	/* May be NULL for unsupported */
247 	char name[64];
248 	struct pid *pgrp;		/* Protected by ctrl lock */
249 	struct pid *session;
250 	unsigned long flags;
251 	int count;
252 	struct winsize winsize;		/* termios mutex */
253 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
254 	unsigned char low_latency:1, warned:1;
255 	unsigned char ctrl_status;	/* ctrl_lock */
256 	unsigned int receive_room;	/* Bytes free for queue */
257 
258 	struct tty_struct *link;
259 	struct fasync_struct *fasync;
260 	struct tty_bufhead buf;		/* Locked internally */
261 	int alt_speed;		/* For magic substitution of 38400 bps */
262 	wait_queue_head_t write_wait;
263 	wait_queue_head_t read_wait;
264 	struct work_struct hangup_work;
265 	void *disc_data;
266 	void *driver_data;
267 	struct list_head tty_files;
268 
269 #define N_TTY_BUF_SIZE 4096
270 
271 	/*
272 	 * The following is data for the N_TTY line discipline.  For
273 	 * historical reasons, this is included in the tty structure.
274 	 * Mostly locked by the BKL.
275 	 */
276 	unsigned int column;
277 	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
278 	unsigned char closing:1;
279 	unsigned char echo_overrun:1;
280 	unsigned short minimum_to_wake;
281 	unsigned long overrun_time;
282 	int num_overrun;
283 	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
284 	char *read_buf;
285 	int read_head;
286 	int read_tail;
287 	int read_cnt;
288 	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
289 	unsigned char *echo_buf;
290 	unsigned int echo_pos;
291 	unsigned int echo_cnt;
292 	int canon_data;
293 	unsigned long canon_head;
294 	unsigned int canon_column;
295 	struct mutex atomic_read_lock;
296 	struct mutex atomic_write_lock;
297 	struct mutex output_lock;
298 	struct mutex echo_lock;
299 	unsigned char *write_buf;
300 	int write_cnt;
301 	spinlock_t read_lock;
302 	/* If the tty has a pending do_SAK, queue it here - akpm */
303 	struct work_struct SAK_work;
304 	struct tty_port *port;
305 };
306 
307 /* tty magic number */
308 #define TTY_MAGIC		0x5401
309 
310 /*
311  * These bits are used in the flags field of the tty structure.
312  *
313  * So that interrupts won't be able to mess up the queues,
314  * copy_to_cooked must be atomic with respect to itself, as must
315  * tty->write.  Thus, you must use the inline functions set_bit() and
316  * clear_bit() to make things atomic.
317  */
318 #define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
319 #define TTY_IO_ERROR 		1	/* Cause an I/O error (may be no ldisc too) */
320 #define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
321 #define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
322 #define TTY_DEBUG 		4	/* Debugging */
323 #define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
324 #define TTY_PUSH 		6	/* n_tty private */
325 #define TTY_CLOSING 		7	/* ->close() in progress */
326 #define TTY_LDISC 		9	/* Line discipline attached */
327 #define TTY_LDISC_CHANGING 	10	/* Line discipline changing */
328 #define TTY_LDISC_OPEN	 	11	/* Line discipline is open */
329 #define TTY_HW_COOK_OUT 	14	/* Hardware can do output cooking */
330 #define TTY_HW_COOK_IN 		15	/* Hardware can do input cooking */
331 #define TTY_PTY_LOCK 		16	/* pty private */
332 #define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
333 #define TTY_HUPPED 		18	/* Post driver->hangup() */
334 #define TTY_FLUSHING		19	/* Flushing to ldisc in progress */
335 #define TTY_FLUSHPENDING	20	/* Queued buffer flush pending */
336 
337 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
338 
339 extern void tty_write_flush(struct tty_struct *);
340 
341 extern struct ktermios tty_std_termios;
342 
343 extern int kmsg_redirect;
344 
345 extern void console_init(void);
346 extern int vcs_init(void);
347 
348 extern struct class *tty_class;
349 
350 /**
351  *	tty_kref_get		-	get a tty reference
352  *	@tty: tty device
353  *
354  *	Return a new reference to a tty object. The caller must hold
355  *	sufficient locks/counts to ensure that their existing reference cannot
356  *	go away
357  */
358 
359 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
360 {
361 	if (tty)
362 		kref_get(&tty->kref);
363 	return tty;
364 }
365 extern void tty_kref_put(struct tty_struct *tty);
366 
367 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
368 			      const char *routine);
369 extern char *tty_name(struct tty_struct *tty, char *buf);
370 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
371 extern int tty_check_change(struct tty_struct *tty);
372 extern void stop_tty(struct tty_struct *tty);
373 extern void start_tty(struct tty_struct *tty);
374 extern int tty_register_driver(struct tty_driver *driver);
375 extern int tty_unregister_driver(struct tty_driver *driver);
376 extern struct device *tty_register_device(struct tty_driver *driver,
377 					  unsigned index, struct device *dev);
378 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
379 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
380 			     int buflen);
381 extern void tty_write_message(struct tty_struct *tty, char *msg);
382 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
383 extern int tty_chars_in_buffer(struct tty_struct *tty);
384 extern int tty_write_room(struct tty_struct *tty);
385 extern void tty_driver_flush_buffer(struct tty_struct *tty);
386 extern void tty_throttle(struct tty_struct *tty);
387 extern void tty_unthrottle(struct tty_struct *tty);
388 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
389 extern void tty_shutdown(struct tty_struct *tty);
390 extern void tty_free_termios(struct tty_struct *tty);
391 extern int is_current_pgrp_orphaned(void);
392 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
393 extern int is_ignored(int sig);
394 extern int tty_signal(int sig, struct tty_struct *tty);
395 extern void tty_hangup(struct tty_struct *tty);
396 extern void tty_vhangup(struct tty_struct *tty);
397 extern void tty_vhangup_self(void);
398 extern void tty_unhangup(struct file *filp);
399 extern int tty_hung_up_p(struct file *filp);
400 extern void do_SAK(struct tty_struct *tty);
401 extern void __do_SAK(struct tty_struct *tty);
402 extern void disassociate_ctty(int priv);
403 extern void no_tty(void);
404 extern void tty_flip_buffer_push(struct tty_struct *tty);
405 extern void tty_flush_to_ldisc(struct tty_struct *tty);
406 extern void tty_buffer_free_all(struct tty_struct *tty);
407 extern void tty_buffer_flush(struct tty_struct *tty);
408 extern void tty_buffer_init(struct tty_struct *tty);
409 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
410 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
411 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
412 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
413 						speed_t ibaud, speed_t obaud);
414 extern void tty_encode_baud_rate(struct tty_struct *tty,
415 						speed_t ibaud, speed_t obaud);
416 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
417 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
418 
419 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
420 extern void tty_ldisc_deref(struct tty_ldisc *);
421 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
422 extern void tty_ldisc_hangup(struct tty_struct *tty);
423 extern const struct file_operations tty_ldiscs_proc_fops;
424 
425 extern void tty_wakeup(struct tty_struct *tty);
426 extern void tty_ldisc_flush(struct tty_struct *tty);
427 
428 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
429 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
430 			unsigned int cmd, unsigned long arg);
431 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
432 extern dev_t tty_devnum(struct tty_struct *tty);
433 extern void proc_clear_tty(struct task_struct *p);
434 extern struct tty_struct *get_current_tty(void);
435 extern void tty_default_fops(struct file_operations *fops);
436 extern struct tty_struct *alloc_tty_struct(void);
437 extern void free_tty_struct(struct tty_struct *tty);
438 extern void initialize_tty_struct(struct tty_struct *tty,
439 		struct tty_driver *driver, int idx);
440 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
441 								int first_ok);
442 extern void tty_release_dev(struct file *filp);
443 extern int tty_init_termios(struct tty_struct *tty);
444 
445 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
446 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
447 
448 extern struct mutex tty_mutex;
449 
450 extern void tty_write_unlock(struct tty_struct *tty);
451 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
452 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
453 
454 extern void tty_port_init(struct tty_port *port);
455 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
456 extern void tty_port_free_xmit_buf(struct tty_port *port);
457 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
458 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
459 extern int tty_port_carrier_raised(struct tty_port *port);
460 extern void tty_port_raise_dtr_rts(struct tty_port *port);
461 extern void tty_port_lower_dtr_rts(struct tty_port *port);
462 extern void tty_port_hangup(struct tty_port *port);
463 extern int tty_port_block_til_ready(struct tty_port *port,
464 				struct tty_struct *tty, struct file *filp);
465 extern int tty_port_close_start(struct tty_port *port,
466 				struct tty_struct *tty, struct file *filp);
467 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
468 extern void tty_port_close(struct tty_port *port,
469 				struct tty_struct *tty, struct file *filp);
470 extern inline int tty_port_users(struct tty_port *port)
471 {
472 	return port->count + port->blocked_open;
473 }
474 
475 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
476 extern int tty_unregister_ldisc(int disc);
477 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
478 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
479 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
480 extern void tty_ldisc_init(struct tty_struct *tty);
481 extern void tty_ldisc_begin(void);
482 /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
483 extern void tty_ldisc_enable(struct tty_struct *tty);
484 
485 
486 /* n_tty.c */
487 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
488 
489 /* tty_audit.c */
490 #ifdef CONFIG_AUDIT
491 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
492 			       size_t size);
493 extern void tty_audit_exit(void);
494 extern void tty_audit_fork(struct signal_struct *sig);
495 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
496 extern void tty_audit_push(struct tty_struct *tty);
497 extern void tty_audit_push_task(struct task_struct *tsk,
498 					uid_t loginuid, u32 sessionid);
499 #else
500 static inline void tty_audit_add_data(struct tty_struct *tty,
501 				      unsigned char *data, size_t size)
502 {
503 }
504 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
505 {
506 }
507 static inline void tty_audit_exit(void)
508 {
509 }
510 static inline void tty_audit_fork(struct signal_struct *sig)
511 {
512 }
513 static inline void tty_audit_push(struct tty_struct *tty)
514 {
515 }
516 static inline void tty_audit_push_task(struct task_struct *tsk,
517 					uid_t loginuid, u32 sessionid)
518 {
519 }
520 #endif
521 
522 /* tty_ioctl.c */
523 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
524 		       unsigned int cmd, unsigned long arg);
525 
526 /* serial.c */
527 
528 extern void serial_console_init(void);
529 
530 /* pcxx.c */
531 
532 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
533 
534 /* vt.c */
535 
536 extern int vt_ioctl(struct tty_struct *tty, struct file *file,
537 		    unsigned int cmd, unsigned long arg);
538 
539 extern long vt_compat_ioctl(struct tty_struct *tty, struct file * file,
540 		     unsigned int cmd, unsigned long arg);
541 
542 #endif /* __KERNEL__ */
543 #endif
544