tty.h revision f23eb2b2b28547fc70df82dd5049eb39bec5ba12
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 <kaz@cafe.net> */
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#define N_TI_WL		22	/* for TI's WL BT, FM, GPS combo chips */
53
54/*
55 * This character is the same as _POSIX_VDISABLE: it cannot be used as
56 * a c_cc[] character, but indicates that a particular special character
57 * isn't in use (eg VINTR has no character etc)
58 */
59#define __DISABLED_CHAR '\0'
60
61struct tty_buffer {
62	struct tty_buffer *next;
63	char *char_buf_ptr;
64	unsigned char *flag_buf_ptr;
65	int used;
66	int size;
67	int commit;
68	int read;
69	/* Data points here */
70	unsigned long data[0];
71};
72
73/*
74 * We default to dicing tty buffer allocations to this many characters
75 * in order to avoid multiple page allocations. We know the size of
76 * tty_buffer itself but it must also be taken into account that the
77 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
78 * logic this must match
79 */
80
81#define TTY_BUFFER_PAGE	(((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
82
83
84struct tty_bufhead {
85	struct work_struct work;
86	spinlock_t lock;
87	struct tty_buffer *head;	/* Queue head */
88	struct tty_buffer *tail;	/* Active buffer */
89	struct tty_buffer *free;	/* Free queue head */
90	int memory_used;		/* Buffer space used excluding
91								free queue */
92};
93/*
94 * When a break, frame error, or parity error happens, these codes are
95 * stuffed into the flags buffer.
96 */
97#define TTY_NORMAL	0
98#define TTY_BREAK	1
99#define TTY_FRAME	2
100#define TTY_PARITY	3
101#define TTY_OVERRUN	4
102
103#define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
104#define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
105#define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
106#define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
107#define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
108#define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
109#define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
110#define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
111#define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
112#define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
113#define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
114#define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
115#define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
116#define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
117#define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
118#define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
119#define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
120
121#define _I_FLAG(tty, f)	((tty)->termios->c_iflag & (f))
122#define _O_FLAG(tty, f)	((tty)->termios->c_oflag & (f))
123#define _C_FLAG(tty, f)	((tty)->termios->c_cflag & (f))
124#define _L_FLAG(tty, f)	((tty)->termios->c_lflag & (f))
125
126#define I_IGNBRK(tty)	_I_FLAG((tty), IGNBRK)
127#define I_BRKINT(tty)	_I_FLAG((tty), BRKINT)
128#define I_IGNPAR(tty)	_I_FLAG((tty), IGNPAR)
129#define I_PARMRK(tty)	_I_FLAG((tty), PARMRK)
130#define I_INPCK(tty)	_I_FLAG((tty), INPCK)
131#define I_ISTRIP(tty)	_I_FLAG((tty), ISTRIP)
132#define I_INLCR(tty)	_I_FLAG((tty), INLCR)
133#define I_IGNCR(tty)	_I_FLAG((tty), IGNCR)
134#define I_ICRNL(tty)	_I_FLAG((tty), ICRNL)
135#define I_IUCLC(tty)	_I_FLAG((tty), IUCLC)
136#define I_IXON(tty)	_I_FLAG((tty), IXON)
137#define I_IXANY(tty)	_I_FLAG((tty), IXANY)
138#define I_IXOFF(tty)	_I_FLAG((tty), IXOFF)
139#define I_IMAXBEL(tty)	_I_FLAG((tty), IMAXBEL)
140#define I_IUTF8(tty)	_I_FLAG((tty), IUTF8)
141
142#define O_OPOST(tty)	_O_FLAG((tty), OPOST)
143#define O_OLCUC(tty)	_O_FLAG((tty), OLCUC)
144#define O_ONLCR(tty)	_O_FLAG((tty), ONLCR)
145#define O_OCRNL(tty)	_O_FLAG((tty), OCRNL)
146#define O_ONOCR(tty)	_O_FLAG((tty), ONOCR)
147#define O_ONLRET(tty)	_O_FLAG((tty), ONLRET)
148#define O_OFILL(tty)	_O_FLAG((tty), OFILL)
149#define O_OFDEL(tty)	_O_FLAG((tty), OFDEL)
150#define O_NLDLY(tty)	_O_FLAG((tty), NLDLY)
151#define O_CRDLY(tty)	_O_FLAG((tty), CRDLY)
152#define O_TABDLY(tty)	_O_FLAG((tty), TABDLY)
153#define O_BSDLY(tty)	_O_FLAG((tty), BSDLY)
154#define O_VTDLY(tty)	_O_FLAG((tty), VTDLY)
155#define O_FFDLY(tty)	_O_FLAG((tty), FFDLY)
156
157#define C_BAUD(tty)	_C_FLAG((tty), CBAUD)
158#define C_CSIZE(tty)	_C_FLAG((tty), CSIZE)
159#define C_CSTOPB(tty)	_C_FLAG((tty), CSTOPB)
160#define C_CREAD(tty)	_C_FLAG((tty), CREAD)
161#define C_PARENB(tty)	_C_FLAG((tty), PARENB)
162#define C_PARODD(tty)	_C_FLAG((tty), PARODD)
163#define C_HUPCL(tty)	_C_FLAG((tty), HUPCL)
164#define C_CLOCAL(tty)	_C_FLAG((tty), CLOCAL)
165#define C_CIBAUD(tty)	_C_FLAG((tty), CIBAUD)
166#define C_CRTSCTS(tty)	_C_FLAG((tty), CRTSCTS)
167
168#define L_ISIG(tty)	_L_FLAG((tty), ISIG)
169#define L_ICANON(tty)	_L_FLAG((tty), ICANON)
170#define L_XCASE(tty)	_L_FLAG((tty), XCASE)
171#define L_ECHO(tty)	_L_FLAG((tty), ECHO)
172#define L_ECHOE(tty)	_L_FLAG((tty), ECHOE)
173#define L_ECHOK(tty)	_L_FLAG((tty), ECHOK)
174#define L_ECHONL(tty)	_L_FLAG((tty), ECHONL)
175#define L_NOFLSH(tty)	_L_FLAG((tty), NOFLSH)
176#define L_TOSTOP(tty)	_L_FLAG((tty), TOSTOP)
177#define L_ECHOCTL(tty)	_L_FLAG((tty), ECHOCTL)
178#define L_ECHOPRT(tty)	_L_FLAG((tty), ECHOPRT)
179#define L_ECHOKE(tty)	_L_FLAG((tty), ECHOKE)
180#define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
181#define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
182#define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
183#define L_EXTPROC(tty)	_L_FLAG((tty), EXTPROC)
184
185struct device;
186struct signal_struct;
187
188/*
189 * Port level information. Each device keeps its own port level information
190 * so provide a common structure for those ports wanting to use common support
191 * routines.
192 *
193 * The tty port has a different lifetime to the tty so must be kept apart.
194 * In addition be careful as tty -> port mappings are valid for the life
195 * of the tty object but in many cases port -> tty mappings are valid only
196 * until a hangup so don't use the wrong path.
197 */
198
199struct tty_port;
200
201struct tty_port_operations {
202	/* Return 1 if the carrier is raised */
203	int (*carrier_raised)(struct tty_port *port);
204	/* Control the DTR line */
205	void (*dtr_rts)(struct tty_port *port, int raise);
206	/* Called when the last close completes or a hangup finishes
207	   IFF the port was initialized. Do not use to free resources. Called
208	   under the port mutex to serialize against activate/shutdowns */
209	void (*shutdown)(struct tty_port *port);
210	void (*drop)(struct tty_port *port);
211	/* Called under the port mutex from tty_port_open, serialized using
212	   the port mutex */
213        /* FIXME: long term getting the tty argument *out* of this would be
214           good for consoles */
215	int (*activate)(struct tty_port *port, struct tty_struct *tty);
216	/* Called on the final put of a port */
217	void (*destruct)(struct tty_port *port);
218};
219
220struct tty_port {
221	struct tty_struct	*tty;		/* Back pointer */
222	const struct tty_port_operations *ops;	/* Port operations */
223	spinlock_t		lock;		/* Lock protecting tty field */
224	int			blocked_open;	/* Waiting to open */
225	int			count;		/* Usage count */
226	wait_queue_head_t	open_wait;	/* Open waiters */
227	wait_queue_head_t	close_wait;	/* Close waiters */
228	wait_queue_head_t	delta_msr_wait;	/* Modem status change */
229	unsigned long		flags;		/* TTY flags ASY_*/
230	unsigned char		console:1;	/* port is a console */
231	struct mutex		mutex;		/* Locking */
232	struct mutex		buf_mutex;	/* Buffer alloc lock */
233	unsigned char		*xmit_buf;	/* Optional buffer */
234	unsigned int		close_delay;	/* Close port delay */
235	unsigned int		closing_wait;	/* Delay for output */
236	int			drain_delay;	/* Set to zero if no pure time
237						   based drain is needed else
238						   set to size of fifo */
239	struct kref		kref;		/* Ref counter */
240};
241
242/*
243 * Where all of the state associated with a tty is kept while the tty
244 * is open.  Since the termios state should be kept even if the tty
245 * has been closed --- for things like the baud rate, etc --- it is
246 * not stored here, but rather a pointer to the real state is stored
247 * here.  Possible the winsize structure should have the same
248 * treatment, but (1) the default 80x24 is usually right and (2) it's
249 * most often used by a windowing system, which will set the correct
250 * size each time the window is created or resized anyway.
251 * 						- TYT, 9/14/92
252 */
253
254struct tty_operations;
255
256struct tty_struct {
257	int	magic;
258	struct kref kref;
259	struct device *dev;
260	struct tty_driver *driver;
261	const struct tty_operations *ops;
262	int index;
263
264	/* Protects ldisc changes: Lock tty not pty */
265	struct mutex ldisc_mutex;
266	struct tty_ldisc *ldisc;
267
268	struct mutex termios_mutex;
269	spinlock_t ctrl_lock;
270	/* Termios values are protected by the termios mutex */
271	struct ktermios *termios, *termios_locked;
272	struct termiox *termiox;	/* May be NULL for unsupported */
273	char name[64];
274	struct pid *pgrp;		/* Protected by ctrl lock */
275	struct pid *session;
276	unsigned long flags;
277	int count;
278	struct winsize winsize;		/* termios mutex */
279	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
280	unsigned char low_latency:1, warned:1;
281	unsigned char ctrl_status;	/* ctrl_lock */
282	unsigned int receive_room;	/* Bytes free for queue */
283
284	struct tty_struct *link;
285	struct fasync_struct *fasync;
286	struct tty_bufhead buf;		/* Locked internally */
287	int alt_speed;		/* For magic substitution of 38400 bps */
288	wait_queue_head_t write_wait;
289	wait_queue_head_t read_wait;
290	struct work_struct hangup_work;
291	void *disc_data;
292	void *driver_data;
293	struct list_head tty_files;
294
295#define N_TTY_BUF_SIZE 4096
296
297	/*
298	 * The following is data for the N_TTY line discipline.  For
299	 * historical reasons, this is included in the tty structure.
300	 * Mostly locked by the BKL.
301	 */
302	unsigned int column;
303	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
304	unsigned char closing:1;
305	unsigned char echo_overrun:1;
306	unsigned short minimum_to_wake;
307	unsigned long overrun_time;
308	int num_overrun;
309	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
310	char *read_buf;
311	int read_head;
312	int read_tail;
313	int read_cnt;
314	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
315	unsigned char *echo_buf;
316	unsigned int echo_pos;
317	unsigned int echo_cnt;
318	int canon_data;
319	unsigned long canon_head;
320	unsigned int canon_column;
321	struct mutex atomic_read_lock;
322	struct mutex atomic_write_lock;
323	struct mutex output_lock;
324	struct mutex echo_lock;
325	unsigned char *write_buf;
326	int write_cnt;
327	spinlock_t read_lock;
328	/* If the tty has a pending do_SAK, queue it here - akpm */
329	struct work_struct SAK_work;
330	struct tty_port *port;
331};
332
333/* Each of a tty's open files has private_data pointing to tty_file_private */
334struct tty_file_private {
335	struct tty_struct *tty;
336	struct file *file;
337	struct list_head list;
338};
339
340/* tty magic number */
341#define TTY_MAGIC		0x5401
342
343/*
344 * These bits are used in the flags field of the tty structure.
345 *
346 * So that interrupts won't be able to mess up the queues,
347 * copy_to_cooked must be atomic with respect to itself, as must
348 * tty->write.  Thus, you must use the inline functions set_bit() and
349 * clear_bit() to make things atomic.
350 */
351#define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
352#define TTY_IO_ERROR 		1	/* Cause an I/O error (may be no ldisc too) */
353#define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
354#define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
355#define TTY_DEBUG 		4	/* Debugging */
356#define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
357#define TTY_PUSH 		6	/* n_tty private */
358#define TTY_CLOSING 		7	/* ->close() in progress */
359#define TTY_LDISC 		9	/* Line discipline attached */
360#define TTY_LDISC_CHANGING 	10	/* Line discipline changing */
361#define TTY_LDISC_OPEN	 	11	/* Line discipline is open */
362#define TTY_HW_COOK_OUT 	14	/* Hardware can do output cooking */
363#define TTY_HW_COOK_IN 		15	/* Hardware can do input cooking */
364#define TTY_PTY_LOCK 		16	/* pty private */
365#define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
366#define TTY_HUPPED 		18	/* Post driver->hangup() */
367#define TTY_FLUSHING		19	/* Flushing to ldisc in progress */
368#define TTY_FLUSHPENDING	20	/* Queued buffer flush pending */
369#define TTY_HUPPING 		21	/* ->hangup() in progress */
370
371#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
372
373extern void tty_write_flush(struct tty_struct *);
374
375extern struct ktermios tty_std_termios;
376
377extern void console_init(void);
378extern int vcs_init(void);
379
380extern struct class *tty_class;
381
382/**
383 *	tty_kref_get		-	get a tty reference
384 *	@tty: tty device
385 *
386 *	Return a new reference to a tty object. The caller must hold
387 *	sufficient locks/counts to ensure that their existing reference cannot
388 *	go away
389 */
390
391static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
392{
393	if (tty)
394		kref_get(&tty->kref);
395	return tty;
396}
397extern void tty_kref_put(struct tty_struct *tty);
398
399extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
400			      const char *routine);
401extern char *tty_name(struct tty_struct *tty, char *buf);
402extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
403extern int tty_check_change(struct tty_struct *tty);
404extern void stop_tty(struct tty_struct *tty);
405extern void start_tty(struct tty_struct *tty);
406extern int tty_register_driver(struct tty_driver *driver);
407extern int tty_unregister_driver(struct tty_driver *driver);
408extern struct device *tty_register_device(struct tty_driver *driver,
409					  unsigned index, struct device *dev);
410extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
411extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
412			     int buflen);
413extern void tty_write_message(struct tty_struct *tty, char *msg);
414extern int tty_put_char(struct tty_struct *tty, unsigned char c);
415extern int tty_chars_in_buffer(struct tty_struct *tty);
416extern int tty_write_room(struct tty_struct *tty);
417extern void tty_driver_flush_buffer(struct tty_struct *tty);
418extern void tty_throttle(struct tty_struct *tty);
419extern void tty_unthrottle(struct tty_struct *tty);
420extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
421extern void tty_shutdown(struct tty_struct *tty);
422extern void tty_free_termios(struct tty_struct *tty);
423extern int is_current_pgrp_orphaned(void);
424extern struct pid *tty_get_pgrp(struct tty_struct *tty);
425extern int is_ignored(int sig);
426extern int tty_signal(int sig, struct tty_struct *tty);
427extern void tty_hangup(struct tty_struct *tty);
428extern void tty_vhangup(struct tty_struct *tty);
429extern void tty_vhangup_locked(struct tty_struct *tty);
430extern void tty_vhangup_self(void);
431extern void tty_unhangup(struct file *filp);
432extern int tty_hung_up_p(struct file *filp);
433extern void do_SAK(struct tty_struct *tty);
434extern void __do_SAK(struct tty_struct *tty);
435extern void disassociate_ctty(int priv);
436extern void no_tty(void);
437extern void tty_flip_buffer_push(struct tty_struct *tty);
438extern void tty_flush_to_ldisc(struct tty_struct *tty);
439extern void tty_buffer_free_all(struct tty_struct *tty);
440extern void tty_buffer_flush(struct tty_struct *tty);
441extern void tty_buffer_init(struct tty_struct *tty);
442extern speed_t tty_get_baud_rate(struct tty_struct *tty);
443extern speed_t tty_termios_baud_rate(struct ktermios *termios);
444extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
445extern void tty_termios_encode_baud_rate(struct ktermios *termios,
446						speed_t ibaud, speed_t obaud);
447extern void tty_encode_baud_rate(struct tty_struct *tty,
448						speed_t ibaud, speed_t obaud);
449extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
450extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
451extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
452
453extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
454extern void tty_ldisc_deref(struct tty_ldisc *);
455extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
456extern void tty_ldisc_hangup(struct tty_struct *tty);
457extern const struct file_operations tty_ldiscs_proc_fops;
458
459extern void tty_wakeup(struct tty_struct *tty);
460extern void tty_ldisc_flush(struct tty_struct *tty);
461
462extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
463extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
464			unsigned int cmd, unsigned long arg);
465extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
466extern dev_t tty_devnum(struct tty_struct *tty);
467extern void proc_clear_tty(struct task_struct *p);
468extern struct tty_struct *get_current_tty(void);
469extern void tty_default_fops(struct file_operations *fops);
470extern struct tty_struct *alloc_tty_struct(void);
471extern int tty_add_file(struct tty_struct *tty, struct file *file);
472extern void free_tty_struct(struct tty_struct *tty);
473extern void initialize_tty_struct(struct tty_struct *tty,
474		struct tty_driver *driver, int idx);
475extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
476								int first_ok);
477extern int tty_release(struct inode *inode, struct file *filp);
478extern int tty_init_termios(struct tty_struct *tty);
479
480extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
481extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
482
483extern struct mutex tty_mutex;
484extern spinlock_t tty_files_lock;
485
486extern void tty_write_unlock(struct tty_struct *tty);
487extern int tty_write_lock(struct tty_struct *tty, int ndelay);
488#define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
489
490extern void tty_port_init(struct tty_port *port);
491extern int tty_port_alloc_xmit_buf(struct tty_port *port);
492extern void tty_port_free_xmit_buf(struct tty_port *port);
493extern void tty_port_put(struct tty_port *port);
494
495static inline struct tty_port *tty_port_get(struct tty_port *port)
496{
497	if (port)
498		kref_get(&port->kref);
499	return port;
500}
501
502extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
503extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
504extern int tty_port_carrier_raised(struct tty_port *port);
505extern void tty_port_raise_dtr_rts(struct tty_port *port);
506extern void tty_port_lower_dtr_rts(struct tty_port *port);
507extern void tty_port_hangup(struct tty_port *port);
508extern int tty_port_block_til_ready(struct tty_port *port,
509				struct tty_struct *tty, struct file *filp);
510extern int tty_port_close_start(struct tty_port *port,
511				struct tty_struct *tty, struct file *filp);
512extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
513extern void tty_port_close(struct tty_port *port,
514				struct tty_struct *tty, struct file *filp);
515extern int tty_port_open(struct tty_port *port,
516				struct tty_struct *tty, struct file *filp);
517static inline int tty_port_users(struct tty_port *port)
518{
519	return port->count + port->blocked_open;
520}
521
522extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
523extern int tty_unregister_ldisc(int disc);
524extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
525extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
526extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
527extern void tty_ldisc_init(struct tty_struct *tty);
528extern void tty_ldisc_begin(void);
529/* This last one is just for the tty layer internals and shouldn't be used elsewhere */
530extern void tty_ldisc_enable(struct tty_struct *tty);
531
532
533/* n_tty.c */
534extern struct tty_ldisc_ops tty_ldisc_N_TTY;
535extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
536
537/* tty_audit.c */
538#ifdef CONFIG_AUDIT
539extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
540			       size_t size);
541extern void tty_audit_exit(void);
542extern void tty_audit_fork(struct signal_struct *sig);
543extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
544extern void tty_audit_push(struct tty_struct *tty);
545extern int tty_audit_push_task(struct task_struct *tsk,
546			       uid_t loginuid, u32 sessionid);
547#else
548static inline void tty_audit_add_data(struct tty_struct *tty,
549				      unsigned char *data, size_t size)
550{
551}
552static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
553{
554}
555static inline void tty_audit_exit(void)
556{
557}
558static inline void tty_audit_fork(struct signal_struct *sig)
559{
560}
561static inline void tty_audit_push(struct tty_struct *tty)
562{
563}
564static inline int tty_audit_push_task(struct task_struct *tsk,
565				      uid_t loginuid, u32 sessionid)
566{
567	return 0;
568}
569#endif
570
571/* tty_io.c */
572extern int __init tty_init(void);
573
574/* tty_ioctl.c */
575extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
576		       unsigned int cmd, unsigned long arg);
577
578/* serial.c */
579
580extern void serial_console_init(void);
581
582/* pcxx.c */
583
584extern int pcxe_open(struct tty_struct *tty, struct file *filp);
585
586/* vt.c */
587
588extern int vt_ioctl(struct tty_struct *tty,
589		    unsigned int cmd, unsigned long arg);
590
591extern long vt_compat_ioctl(struct tty_struct *tty,
592		     unsigned int cmd, unsigned long arg);
593
594/* tty_mutex.c */
595/* functions for preparation of BKL removal */
596extern void __lockfunc tty_lock(void) __acquires(tty_lock);
597extern void __lockfunc tty_unlock(void) __releases(tty_lock);
598extern struct task_struct *__big_tty_mutex_owner;
599#define tty_locked()		(current == __big_tty_mutex_owner)
600
601/*
602 * wait_event_interruptible_tty -- wait for a condition with the tty lock held
603 *
604 * The condition we are waiting for might take a long time to
605 * become true, or might depend on another thread taking the
606 * BTM. In either case, we need to drop the BTM to guarantee
607 * forward progress. This is a leftover from the conversion
608 * from the BKL and should eventually get removed as the BTM
609 * falls out of use.
610 *
611 * Do not use in new code.
612 */
613#define wait_event_interruptible_tty(wq, condition)			\
614({									\
615	int __ret = 0;							\
616	if (!(condition)) {						\
617		__wait_event_interruptible_tty(wq, condition, __ret);	\
618	}								\
619	__ret;								\
620})
621
622#define __wait_event_interruptible_tty(wq, condition, ret)		\
623do {									\
624	DEFINE_WAIT(__wait);						\
625									\
626	for (;;) {							\
627		prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);	\
628		if (condition)						\
629			break;						\
630		if (!signal_pending(current)) {				\
631			tty_unlock();					\
632			schedule();					\
633			tty_lock();					\
634			continue;					\
635		}							\
636		ret = -ERESTARTSYS;					\
637		break;							\
638	}								\
639	finish_wait(&wq, &__wait);					\
640} while (0)
641
642
643#endif /* __KERNEL__ */
644#endif
645