xref: /linux-6.15/include/linux/tty.h (revision df92b408)
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		30
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 #define N_V253		19	/* Codec control over voice modem */
50 #define N_CAIF		20      /* CAIF protocol for talking to modems */
51 #define N_GSM0710	21	/* GSM 0710 Mux */
52 
53 /*
54  * This character is the same as _POSIX_VDISABLE: it cannot be used as
55  * a c_cc[] character, but indicates that a particular special character
56  * isn't in use (eg VINTR has no character etc)
57  */
58 #define __DISABLED_CHAR '\0'
59 
60 struct tty_buffer {
61 	struct tty_buffer *next;
62 	char *char_buf_ptr;
63 	unsigned char *flag_buf_ptr;
64 	int used;
65 	int size;
66 	int commit;
67 	int read;
68 	/* Data points here */
69 	unsigned long data[0];
70 };
71 
72 /*
73  * We default to dicing tty buffer allocations to this many characters
74  * in order to avoid multiple page allocations. We know the size of
75  * tty_buffer itself but it must also be taken into account that the
76  * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
77  * logic this must match
78  */
79 
80 #define TTY_BUFFER_PAGE	(((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
81 
82 
83 struct tty_bufhead {
84 	struct delayed_work work;
85 	spinlock_t lock;
86 	struct tty_buffer *head;	/* Queue head */
87 	struct tty_buffer *tail;	/* Active buffer */
88 	struct tty_buffer *free;	/* Free queue head */
89 	int memory_used;		/* Buffer space used excluding
90 								free queue */
91 };
92 /*
93  * When a break, frame error, or parity error happens, these codes are
94  * stuffed into the flags buffer.
95  */
96 #define TTY_NORMAL	0
97 #define TTY_BREAK	1
98 #define TTY_FRAME	2
99 #define TTY_PARITY	3
100 #define TTY_OVERRUN	4
101 
102 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
103 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
104 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
105 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
106 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
107 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
108 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
109 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
110 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
111 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
112 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
113 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
114 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
115 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
116 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
117 #define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
118 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
119 
120 #define _I_FLAG(tty, f)	((tty)->termios->c_iflag & (f))
121 #define _O_FLAG(tty, f)	((tty)->termios->c_oflag & (f))
122 #define _C_FLAG(tty, f)	((tty)->termios->c_cflag & (f))
123 #define _L_FLAG(tty, f)	((tty)->termios->c_lflag & (f))
124 
125 #define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
126 #define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
127 #define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
128 #define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
129 #define I_INPCK(tty)	_I_FLAG((tty), INPCK)
130 #define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
131 #define I_INLCR(tty)	_I_FLAG((tty), INLCR)
132 #define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
133 #define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
134 #define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
135 #define I_IXON(tty)	_I_FLAG((tty), IXON)
136 #define I_IXANY(tty)	_I_FLAG((tty), IXANY)
137 #define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
138 #define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
139 #define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
140 
141 #define O_OPOST(tty)	_O_FLAG((tty), OPOST)
142 #define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
143 #define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
144 #define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
145 #define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
146 #define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
147 #define O_OFILL(tty)	_O_FLAG((tty), OFILL)
148 #define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
149 #define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
150 #define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
151 #define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
152 #define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
153 #define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
154 #define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
155 
156 #define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
157 #define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
158 #define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
159 #define C_CREAD(tty)	_C_FLAG((tty), CREAD)
160 #define C_PARENB(tty)	_C_FLAG((tty), PARENB)
161 #define C_PARODD(tty)	_C_FLAG((tty), PARODD)
162 #define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
163 #define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
164 #define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
165 #define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
166 
167 #define L_ISIG(tty)	_L_FLAG((tty), ISIG)
168 #define L_ICANON(tty)	_L_FLAG((tty), ICANON)
169 #define L_XCASE(tty)	_L_FLAG((tty), XCASE)
170 #define L_ECHO(tty)	_L_FLAG((tty), ECHO)
171 #define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
172 #define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
173 #define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
174 #define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
175 #define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
176 #define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
177 #define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
178 #define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
179 #define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
180 #define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
181 #define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
182 
183 struct device;
184 struct signal_struct;
185 
186 /*
187  * Port level information. Each device keeps its own port level information
188  * so provide a common structure for those ports wanting to use common support
189  * routines.
190  *
191  * The tty port has a different lifetime to the tty so must be kept apart.
192  * In addition be careful as tty -> port mappings are valid for the life
193  * of the tty object but in many cases port -> tty mappings are valid only
194  * until a hangup so don't use the wrong path.
195  */
196 
197 struct tty_port;
198 
199 struct tty_port_operations {
200 	/* Return 1 if the carrier is raised */
201 	int (*carrier_raised)(struct tty_port *port);
202 	/* Control the DTR line */
203 	void (*dtr_rts)(struct tty_port *port, int raise);
204 	/* Called when the last close completes or a hangup finishes
205 	   IFF the port was initialized. Do not use to free resources. Called
206 	   under the port mutex to serialize against activate/shutdowns */
207 	void (*shutdown)(struct tty_port *port);
208 	void (*drop)(struct tty_port *port);
209 	/* Called under the port mutex from tty_port_open, serialized using
210 	   the port mutex */
211         /* FIXME: long term getting the tty argument *out* of this would be
212            good for consoles */
213 	int (*activate)(struct tty_port *port, struct tty_struct *tty);
214 	/* Called on the final put of a port */
215 	void (*destruct)(struct tty_port *port);
216 };
217 
218 struct tty_port {
219 	struct tty_struct	*tty;		/* Back pointer */
220 	const struct tty_port_operations *ops;	/* Port operations */
221 	spinlock_t		lock;		/* Lock protecting tty field */
222 	int			blocked_open;	/* Waiting to open */
223 	int			count;		/* Usage count */
224 	wait_queue_head_t	open_wait;	/* Open waiters */
225 	wait_queue_head_t	close_wait;	/* Close waiters */
226 	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
227 	unsigned long		flags;		/* TTY flags ASY_*/
228 	unsigned char		console:1;	/* port is a console */
229 	struct mutex		mutex;		/* Locking */
230 	struct mutex		buf_mutex;	/* Buffer alloc lock */
231 	unsigned char		*xmit_buf;	/* Optional buffer */
232 	unsigned int		close_delay;	/* Close port delay */
233 	unsigned int		closing_wait;	/* Delay for output */
234 	int			drain_delay;	/* Set to zero if no pure time
235 						   based drain is needed else
236 						   set to size of fifo */
237 	struct kref		kref;		/* Ref counter */
238 };
239 
240 /*
241  * Where all of the state associated with a tty is kept while the tty
242  * is open.  Since the termios state should be kept even if the tty
243  * has been closed --- for things like the baud rate, etc --- it is
244  * not stored here, but rather a pointer to the real state is stored
245  * here.  Possible the winsize structure should have the same
246  * treatment, but (1) the default 80x24 is usually right and (2) it's
247  * most often used by a windowing system, which will set the correct
248  * size each time the window is created or resized anyway.
249  * 						- TYT, 9/14/92
250  */
251 
252 struct tty_operations;
253 
254 struct tty_struct {
255 	int	magic;
256 	struct kref kref;
257 	struct tty_driver *driver;
258 	const struct tty_operations *ops;
259 	int index;
260 
261 	/* Protects ldisc changes: Lock tty not pty */
262 	struct mutex ldisc_mutex;
263 	struct tty_ldisc *ldisc;
264 
265 	struct mutex termios_mutex;
266 	spinlock_t ctrl_lock;
267 	/* Termios values are protected by the termios mutex */
268 	struct ktermios *termios, *termios_locked;
269 	struct termiox *termiox;	/* May be NULL for unsupported */
270 	char name[64];
271 	struct pid *pgrp;		/* Protected by ctrl lock */
272 	struct pid *session;
273 	unsigned long flags;
274 	int count;
275 	struct winsize winsize;		/* termios mutex */
276 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
277 	unsigned char low_latency:1, warned:1;
278 	unsigned char ctrl_status;	/* ctrl_lock */
279 	unsigned int receive_room;	/* Bytes free for queue */
280 
281 	struct tty_struct *link;
282 	struct fasync_struct *fasync;
283 	struct tty_bufhead buf;		/* Locked internally */
284 	int alt_speed;		/* For magic substitution of 38400 bps */
285 	wait_queue_head_t write_wait;
286 	wait_queue_head_t read_wait;
287 	struct work_struct hangup_work;
288 	void *disc_data;
289 	void *driver_data;
290 	struct list_head tty_files;
291 
292 #define N_TTY_BUF_SIZE 4096
293 
294 	/*
295 	 * The following is data for the N_TTY line discipline.  For
296 	 * historical reasons, this is included in the tty structure.
297 	 * Mostly locked by the BKL.
298 	 */
299 	unsigned int column;
300 	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
301 	unsigned char closing:1;
302 	unsigned char echo_overrun:1;
303 	unsigned short minimum_to_wake;
304 	unsigned long overrun_time;
305 	int num_overrun;
306 	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
307 	char *read_buf;
308 	int read_head;
309 	int read_tail;
310 	int read_cnt;
311 	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
312 	unsigned char *echo_buf;
313 	unsigned int echo_pos;
314 	unsigned int echo_cnt;
315 	int canon_data;
316 	unsigned long canon_head;
317 	unsigned int canon_column;
318 	struct mutex atomic_read_lock;
319 	struct mutex atomic_write_lock;
320 	struct mutex output_lock;
321 	struct mutex echo_lock;
322 	unsigned char *write_buf;
323 	int write_cnt;
324 	spinlock_t read_lock;
325 	/* If the tty has a pending do_SAK, queue it here - akpm */
326 	struct work_struct SAK_work;
327 	struct tty_port *port;
328 };
329 
330 /* tty magic number */
331 #define TTY_MAGIC		0x5401
332 
333 /*
334  * These bits are used in the flags field of the tty structure.
335  *
336  * So that interrupts won't be able to mess up the queues,
337  * copy_to_cooked must be atomic with respect to itself, as must
338  * tty->write.  Thus, you must use the inline functions set_bit() and
339  * clear_bit() to make things atomic.
340  */
341 #define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
342 #define TTY_IO_ERROR 		1	/* Cause an I/O error (may be no ldisc too) */
343 #define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
344 #define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
345 #define TTY_DEBUG 		4	/* Debugging */
346 #define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
347 #define TTY_PUSH 		6	/* n_tty private */
348 #define TTY_CLOSING 		7	/* ->close() in progress */
349 #define TTY_LDISC 		9	/* Line discipline attached */
350 #define TTY_LDISC_CHANGING 	10	/* Line discipline changing */
351 #define TTY_LDISC_OPEN	 	11	/* Line discipline is open */
352 #define TTY_HW_COOK_OUT 	14	/* Hardware can do output cooking */
353 #define TTY_HW_COOK_IN 		15	/* Hardware can do input cooking */
354 #define TTY_PTY_LOCK 		16	/* pty private */
355 #define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
356 #define TTY_HUPPED 		18	/* Post driver->hangup() */
357 #define TTY_FLUSHING		19	/* Flushing to ldisc in progress */
358 #define TTY_FLUSHPENDING	20	/* Queued buffer flush pending */
359 
360 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
361 
362 extern void tty_write_flush(struct tty_struct *);
363 
364 extern struct ktermios tty_std_termios;
365 
366 extern void console_init(void);
367 extern int vcs_init(void);
368 
369 extern struct class *tty_class;
370 
371 /**
372  *	tty_kref_get		-	get a tty reference
373  *	@tty: tty device
374  *
375  *	Return a new reference to a tty object. The caller must hold
376  *	sufficient locks/counts to ensure that their existing reference cannot
377  *	go away
378  */
379 
380 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
381 {
382 	if (tty)
383 		kref_get(&tty->kref);
384 	return tty;
385 }
386 extern void tty_kref_put(struct tty_struct *tty);
387 
388 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
389 			      const char *routine);
390 extern char *tty_name(struct tty_struct *tty, char *buf);
391 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
392 extern int tty_check_change(struct tty_struct *tty);
393 extern void stop_tty(struct tty_struct *tty);
394 extern void start_tty(struct tty_struct *tty);
395 extern int tty_register_driver(struct tty_driver *driver);
396 extern int tty_unregister_driver(struct tty_driver *driver);
397 extern struct device *tty_register_device(struct tty_driver *driver,
398 					  unsigned index, struct device *dev);
399 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
400 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
401 			     int buflen);
402 extern void tty_write_message(struct tty_struct *tty, char *msg);
403 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
404 extern int tty_chars_in_buffer(struct tty_struct *tty);
405 extern int tty_write_room(struct tty_struct *tty);
406 extern void tty_driver_flush_buffer(struct tty_struct *tty);
407 extern void tty_throttle(struct tty_struct *tty);
408 extern void tty_unthrottle(struct tty_struct *tty);
409 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
410 extern void tty_shutdown(struct tty_struct *tty);
411 extern void tty_free_termios(struct tty_struct *tty);
412 extern int is_current_pgrp_orphaned(void);
413 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
414 extern int is_ignored(int sig);
415 extern int tty_signal(int sig, struct tty_struct *tty);
416 extern void tty_hangup(struct tty_struct *tty);
417 extern void tty_vhangup(struct tty_struct *tty);
418 extern void tty_vhangup_self(void);
419 extern void tty_unhangup(struct file *filp);
420 extern int tty_hung_up_p(struct file *filp);
421 extern void do_SAK(struct tty_struct *tty);
422 extern void __do_SAK(struct tty_struct *tty);
423 extern void disassociate_ctty(int priv);
424 extern void no_tty(void);
425 extern void tty_flip_buffer_push(struct tty_struct *tty);
426 extern void tty_flush_to_ldisc(struct tty_struct *tty);
427 extern void tty_buffer_free_all(struct tty_struct *tty);
428 extern void tty_buffer_flush(struct tty_struct *tty);
429 extern void tty_buffer_init(struct tty_struct *tty);
430 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
431 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
432 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
433 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
434 						speed_t ibaud, speed_t obaud);
435 extern void tty_encode_baud_rate(struct tty_struct *tty,
436 						speed_t ibaud, speed_t obaud);
437 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
438 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
439 
440 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
441 extern void tty_ldisc_deref(struct tty_ldisc *);
442 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
443 extern void tty_ldisc_hangup(struct tty_struct *tty);
444 extern const struct file_operations tty_ldiscs_proc_fops;
445 
446 extern void tty_wakeup(struct tty_struct *tty);
447 extern void tty_ldisc_flush(struct tty_struct *tty);
448 
449 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
450 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
451 			unsigned int cmd, unsigned long arg);
452 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
453 extern dev_t tty_devnum(struct tty_struct *tty);
454 extern void proc_clear_tty(struct task_struct *p);
455 extern struct tty_struct *get_current_tty(void);
456 extern void tty_default_fops(struct file_operations *fops);
457 extern struct tty_struct *alloc_tty_struct(void);
458 extern void free_tty_struct(struct tty_struct *tty);
459 extern void initialize_tty_struct(struct tty_struct *tty,
460 		struct tty_driver *driver, int idx);
461 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
462 								int first_ok);
463 extern int tty_release(struct inode *inode, struct file *filp);
464 extern int tty_init_termios(struct tty_struct *tty);
465 
466 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
467 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
468 
469 extern struct mutex tty_mutex;
470 
471 extern void tty_write_unlock(struct tty_struct *tty);
472 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
473 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
474 
475 extern void tty_port_init(struct tty_port *port);
476 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
477 extern void tty_port_free_xmit_buf(struct tty_port *port);
478 extern void tty_port_put(struct tty_port *port);
479 
480 static inline struct tty_port *tty_port_get(struct tty_port *port)
481 {
482 	if (port)
483 		kref_get(&port->kref);
484 	return port;
485 }
486 
487 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
488 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
489 extern int tty_port_carrier_raised(struct tty_port *port);
490 extern void tty_port_raise_dtr_rts(struct tty_port *port);
491 extern void tty_port_lower_dtr_rts(struct tty_port *port);
492 extern void tty_port_hangup(struct tty_port *port);
493 extern int tty_port_block_til_ready(struct tty_port *port,
494 				struct tty_struct *tty, struct file *filp);
495 extern int tty_port_close_start(struct tty_port *port,
496 				struct tty_struct *tty, struct file *filp);
497 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
498 extern void tty_port_close(struct tty_port *port,
499 				struct tty_struct *tty, struct file *filp);
500 extern int tty_port_open(struct tty_port *port,
501 				struct tty_struct *tty, struct file *filp);
502 static inline int tty_port_users(struct tty_port *port)
503 {
504 	return port->count + port->blocked_open;
505 }
506 
507 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
508 extern int tty_unregister_ldisc(int disc);
509 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
510 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
511 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
512 extern void tty_ldisc_init(struct tty_struct *tty);
513 extern void tty_ldisc_begin(void);
514 /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
515 extern void tty_ldisc_enable(struct tty_struct *tty);
516 
517 
518 /* n_tty.c */
519 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
520 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
521 
522 /* tty_audit.c */
523 #ifdef CONFIG_AUDIT
524 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
525 			       size_t size);
526 extern void tty_audit_exit(void);
527 extern void tty_audit_fork(struct signal_struct *sig);
528 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
529 extern void tty_audit_push(struct tty_struct *tty);
530 extern void tty_audit_push_task(struct task_struct *tsk,
531 					uid_t loginuid, u32 sessionid);
532 #else
533 static inline void tty_audit_add_data(struct tty_struct *tty,
534 				      unsigned char *data, size_t size)
535 {
536 }
537 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
538 {
539 }
540 static inline void tty_audit_exit(void)
541 {
542 }
543 static inline void tty_audit_fork(struct signal_struct *sig)
544 {
545 }
546 static inline void tty_audit_push(struct tty_struct *tty)
547 {
548 }
549 static inline void tty_audit_push_task(struct task_struct *tsk,
550 					uid_t loginuid, u32 sessionid)
551 {
552 }
553 #endif
554 
555 /* tty_ioctl.c */
556 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
557 		       unsigned int cmd, unsigned long arg);
558 
559 /* serial.c */
560 
561 extern void serial_console_init(void);
562 
563 /* pcxx.c */
564 
565 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
566 
567 /* vt.c */
568 
569 extern int vt_ioctl(struct tty_struct *tty, struct file *file,
570 		    unsigned int cmd, unsigned long arg);
571 
572 extern long vt_compat_ioctl(struct tty_struct *tty, struct file * file,
573 		     unsigned int cmd, unsigned long arg);
574 
575 #endif /* __KERNEL__ */
576 #endif
577