xref: /linux-6.15/include/linux/tty.h (revision 43f5b308)
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		18
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 <[email protected]> */
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 
49 /*
50  * This character is the same as _POSIX_VDISABLE: it cannot be used as
51  * a c_cc[] character, but indicates that a particular special character
52  * isn't in use (eg VINTR has no character etc)
53  */
54 #define __DISABLED_CHAR '\0'
55 
56 struct tty_buffer {
57 	struct tty_buffer *next;
58 	char *char_buf_ptr;
59 	unsigned char *flag_buf_ptr;
60 	int used;
61 	int size;
62 	int commit;
63 	int read;
64 	/* Data points here */
65 	unsigned long data[0];
66 };
67 
68 struct tty_bufhead {
69 	struct delayed_work work;
70 	spinlock_t lock;
71 	struct tty_buffer *head;	/* Queue head */
72 	struct tty_buffer *tail;	/* Active buffer */
73 	struct tty_buffer *free;	/* Free queue head */
74 	int memory_used;		/* Buffer space used excluding free queue */
75 };
76 /*
77  * When a break, frame error, or parity error happens, these codes are
78  * stuffed into the flags buffer.
79  */
80 #define TTY_NORMAL	0
81 #define TTY_BREAK	1
82 #define TTY_FRAME	2
83 #define TTY_PARITY	3
84 #define TTY_OVERRUN	4
85 
86 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
87 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
88 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
89 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
90 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
91 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
92 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
93 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
94 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
95 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
96 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
97 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
98 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
99 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
100 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
101 #define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
102 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
103 
104 #define _I_FLAG(tty,f)	((tty)->termios->c_iflag & (f))
105 #define _O_FLAG(tty,f)	((tty)->termios->c_oflag & (f))
106 #define _C_FLAG(tty,f)	((tty)->termios->c_cflag & (f))
107 #define _L_FLAG(tty,f)	((tty)->termios->c_lflag & (f))
108 
109 #define I_IGNBRK(tty)	_I_FLAG((tty),IGNBRK)
110 #define I_BRKINT(tty)	_I_FLAG((tty),BRKINT)
111 #define I_IGNPAR(tty)	_I_FLAG((tty),IGNPAR)
112 #define I_PARMRK(tty)	_I_FLAG((tty),PARMRK)
113 #define I_INPCK(tty)	_I_FLAG((tty),INPCK)
114 #define I_ISTRIP(tty)	_I_FLAG((tty),ISTRIP)
115 #define I_INLCR(tty)	_I_FLAG((tty),INLCR)
116 #define I_IGNCR(tty)	_I_FLAG((tty),IGNCR)
117 #define I_ICRNL(tty)	_I_FLAG((tty),ICRNL)
118 #define I_IUCLC(tty)	_I_FLAG((tty),IUCLC)
119 #define I_IXON(tty)	_I_FLAG((tty),IXON)
120 #define I_IXANY(tty)	_I_FLAG((tty),IXANY)
121 #define I_IXOFF(tty)	_I_FLAG((tty),IXOFF)
122 #define I_IMAXBEL(tty)	_I_FLAG((tty),IMAXBEL)
123 #define I_IUTF8(tty)	_I_FLAG((tty),IUTF8)
124 
125 #define O_OPOST(tty)	_O_FLAG((tty),OPOST)
126 #define O_OLCUC(tty)	_O_FLAG((tty),OLCUC)
127 #define O_ONLCR(tty)	_O_FLAG((tty),ONLCR)
128 #define O_OCRNL(tty)	_O_FLAG((tty),OCRNL)
129 #define O_ONOCR(tty)	_O_FLAG((tty),ONOCR)
130 #define O_ONLRET(tty)	_O_FLAG((tty),ONLRET)
131 #define O_OFILL(tty)	_O_FLAG((tty),OFILL)
132 #define O_OFDEL(tty)	_O_FLAG((tty),OFDEL)
133 #define O_NLDLY(tty)	_O_FLAG((tty),NLDLY)
134 #define O_CRDLY(tty)	_O_FLAG((tty),CRDLY)
135 #define O_TABDLY(tty)	_O_FLAG((tty),TABDLY)
136 #define O_BSDLY(tty)	_O_FLAG((tty),BSDLY)
137 #define O_VTDLY(tty)	_O_FLAG((tty),VTDLY)
138 #define O_FFDLY(tty)	_O_FLAG((tty),FFDLY)
139 
140 #define C_BAUD(tty)	_C_FLAG((tty),CBAUD)
141 #define C_CSIZE(tty)	_C_FLAG((tty),CSIZE)
142 #define C_CSTOPB(tty)	_C_FLAG((tty),CSTOPB)
143 #define C_CREAD(tty)	_C_FLAG((tty),CREAD)
144 #define C_PARENB(tty)	_C_FLAG((tty),PARENB)
145 #define C_PARODD(tty)	_C_FLAG((tty),PARODD)
146 #define C_HUPCL(tty)	_C_FLAG((tty),HUPCL)
147 #define C_CLOCAL(tty)	_C_FLAG((tty),CLOCAL)
148 #define C_CIBAUD(tty)	_C_FLAG((tty),CIBAUD)
149 #define C_CRTSCTS(tty)	_C_FLAG((tty),CRTSCTS)
150 
151 #define L_ISIG(tty)	_L_FLAG((tty),ISIG)
152 #define L_ICANON(tty)	_L_FLAG((tty),ICANON)
153 #define L_XCASE(tty)	_L_FLAG((tty),XCASE)
154 #define L_ECHO(tty)	_L_FLAG((tty),ECHO)
155 #define L_ECHOE(tty)	_L_FLAG((tty),ECHOE)
156 #define L_ECHOK(tty)	_L_FLAG((tty),ECHOK)
157 #define L_ECHONL(tty)	_L_FLAG((tty),ECHONL)
158 #define L_NOFLSH(tty)	_L_FLAG((tty),NOFLSH)
159 #define L_TOSTOP(tty)	_L_FLAG((tty),TOSTOP)
160 #define L_ECHOCTL(tty)	_L_FLAG((tty),ECHOCTL)
161 #define L_ECHOPRT(tty)	_L_FLAG((tty),ECHOPRT)
162 #define L_ECHOKE(tty)	_L_FLAG((tty),ECHOKE)
163 #define L_FLUSHO(tty)	_L_FLAG((tty),FLUSHO)
164 #define L_PENDIN(tty)	_L_FLAG((tty),PENDIN)
165 #define L_IEXTEN(tty)	_L_FLAG((tty),IEXTEN)
166 
167 struct device;
168 struct signal_struct;
169 /*
170  * Where all of the state associated with a tty is kept while the tty
171  * is open.  Since the termios state should be kept even if the tty
172  * has been closed --- for things like the baud rate, etc --- it is
173  * not stored here, but rather a pointer to the real state is stored
174  * here.  Possible the winsize structure should have the same
175  * treatment, but (1) the default 80x24 is usually right and (2) it's
176  * most often used by a windowing system, which will set the correct
177  * size each time the window is created or resized anyway.
178  * 						- TYT, 9/14/92
179  */
180 
181 struct tty_operations;
182 
183 struct tty_struct {
184 	int	magic;
185 	struct tty_driver *driver;
186 	const struct tty_operations *ops;
187 	int index;
188 	struct tty_ldisc ldisc;
189 	struct mutex termios_mutex;
190 	spinlock_t ctrl_lock;
191 	/* Termios values are protected by the termios mutex */
192 	struct ktermios *termios, *termios_locked;
193 	char name[64];
194 	struct pid *pgrp;		/* Protected by ctrl lock */
195 	struct pid *session;
196 	unsigned long flags;
197 	int count;
198 	struct winsize winsize;		/* termios mutex */
199 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
200 	unsigned char low_latency:1, warned:1;
201 	unsigned char ctrl_status;	/* ctrl_lock */
202 	unsigned int receive_room;	/* Bytes free for queue */
203 
204 	struct tty_struct *link;
205 	struct fasync_struct *fasync;
206 	struct tty_bufhead buf;		/* Locked internally */
207 	int alt_speed;		/* For magic substitution of 38400 bps */
208 	wait_queue_head_t write_wait;
209 	wait_queue_head_t read_wait;
210 	struct work_struct hangup_work;
211 	void *disc_data;
212 	void *driver_data;
213 	struct list_head tty_files;
214 
215 #define N_TTY_BUF_SIZE 4096
216 
217 	/*
218 	 * The following is data for the N_TTY line discipline.  For
219 	 * historical reasons, this is included in the tty structure.
220 	 * Mostly locked by the BKL.
221 	 */
222 	unsigned int column;
223 	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
224 	unsigned char closing:1;
225 	unsigned short minimum_to_wake;
226 	unsigned long overrun_time;
227 	int num_overrun;
228 	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
229 	char *read_buf;
230 	int read_head;
231 	int read_tail;
232 	int read_cnt;
233 	unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
234 	int canon_data;
235 	unsigned long canon_head;
236 	unsigned int canon_column;
237 	struct mutex atomic_read_lock;
238 	struct mutex atomic_write_lock;
239 	unsigned char *write_buf;
240 	int write_cnt;
241 	spinlock_t read_lock;
242 	/* If the tty has a pending do_SAK, queue it here - akpm */
243 	struct work_struct SAK_work;
244 };
245 
246 /* tty magic number */
247 #define TTY_MAGIC		0x5401
248 
249 /*
250  * These bits are used in the flags field of the tty structure.
251  *
252  * So that interrupts won't be able to mess up the queues,
253  * copy_to_cooked must be atomic with respect to itself, as must
254  * tty->write.  Thus, you must use the inline functions set_bit() and
255  * clear_bit() to make things atomic.
256  */
257 #define TTY_THROTTLED 		0	/* Call unthrottle() at threshold min */
258 #define TTY_IO_ERROR 		1	/* Canse an I/O error (may be no ldisc too) */
259 #define TTY_OTHER_CLOSED 	2	/* Other side (if any) has closed */
260 #define TTY_EXCLUSIVE 		3	/* Exclusive open mode */
261 #define TTY_DEBUG 		4	/* Debugging */
262 #define TTY_DO_WRITE_WAKEUP 	5	/* Call write_wakeup after queuing new */
263 #define TTY_PUSH 		6	/* n_tty private */
264 #define TTY_CLOSING 		7	/* ->close() in progress */
265 #define TTY_LDISC 		9	/* Line discipline attached */
266 #define TTY_HW_COOK_OUT 	14	/* Hardware can do output cooking */
267 #define TTY_HW_COOK_IN 		15	/* Hardware can do input cooking */
268 #define TTY_PTY_LOCK 		16	/* pty private */
269 #define TTY_NO_WRITE_SPLIT 	17	/* Preserve write boundaries to driver */
270 #define TTY_HUPPED 		18	/* Post driver->hangup() */
271 #define TTY_FLUSHING		19	/* Flushing to ldisc in progress */
272 #define TTY_FLUSHPENDING	20	/* Queued buffer flush pending */
273 
274 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
275 
276 extern void tty_write_flush(struct tty_struct *);
277 
278 extern struct ktermios tty_std_termios;
279 
280 extern int kmsg_redirect;
281 
282 extern void console_init(void);
283 extern int vcs_init(void);
284 
285 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
286 			      const char *routine);
287 extern char *tty_name(struct tty_struct *tty, char *buf);
288 extern void tty_wait_until_sent(struct tty_struct * tty, long timeout);
289 extern int tty_check_change(struct tty_struct * tty);
290 extern void stop_tty(struct tty_struct * tty);
291 extern void start_tty(struct tty_struct * tty);
292 extern int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc);
293 extern int tty_unregister_ldisc(int disc);
294 extern int tty_register_driver(struct tty_driver *driver);
295 extern int tty_unregister_driver(struct tty_driver *driver);
296 extern struct device *tty_register_device(struct tty_driver *driver,
297 					  unsigned index, struct device *dev);
298 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
299 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
300 			     int buflen);
301 extern void tty_write_message(struct tty_struct *tty, char *msg);
302 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
303 extern int tty_chars_in_buffer(struct tty_struct *tty);
304 extern int tty_write_room(struct tty_struct *tty);
305 extern void tty_driver_flush_buffer(struct tty_struct *tty);
306 extern void tty_throttle(struct tty_struct *tty);
307 extern void tty_unthrottle(struct tty_struct *tty);
308 
309 extern int is_current_pgrp_orphaned(void);
310 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
311 extern int is_ignored(int sig);
312 extern int tty_signal(int sig, struct tty_struct *tty);
313 extern void tty_hangup(struct tty_struct * tty);
314 extern void tty_vhangup(struct tty_struct * tty);
315 extern void tty_unhangup(struct file *filp);
316 extern int tty_hung_up_p(struct file * filp);
317 extern void do_SAK(struct tty_struct *tty);
318 extern void __do_SAK(struct tty_struct *tty);
319 extern void disassociate_ctty(int priv);
320 extern void no_tty(void);
321 extern void tty_flip_buffer_push(struct tty_struct *tty);
322 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
323 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
324 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
325 extern void tty_termios_encode_baud_rate(struct ktermios *termios, speed_t ibaud, speed_t obaud);
326 extern void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud);
327 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
328 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
329 
330 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
331 extern void tty_ldisc_deref(struct tty_ldisc *);
332 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
333 
334 extern struct tty_ldisc *tty_ldisc_get(int);
335 extern void tty_ldisc_put(int);
336 
337 extern void tty_wakeup(struct tty_struct *tty);
338 extern void tty_ldisc_flush(struct tty_struct *tty);
339 
340 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
341 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
342 			unsigned int cmd, unsigned long arg);
343 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
344 extern dev_t tty_devnum(struct tty_struct *tty);
345 extern void proc_clear_tty(struct task_struct *p);
346 extern struct tty_struct *get_current_tty(void);
347 
348 extern struct mutex tty_mutex;
349 
350 extern void tty_write_unlock(struct tty_struct *tty);
351 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
352 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
353 
354 
355 
356 /* n_tty.c */
357 extern struct tty_ldisc tty_ldisc_N_TTY;
358 
359 /* tty_audit.c */
360 #ifdef CONFIG_AUDIT
361 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
362 			       size_t size);
363 extern void tty_audit_exit(void);
364 extern void tty_audit_fork(struct signal_struct *sig);
365 extern void tty_audit_push(struct tty_struct *tty);
366 extern void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid);
367 #else
368 static inline void tty_audit_add_data(struct tty_struct *tty,
369 				      unsigned char *data, size_t size)
370 {
371 }
372 static inline void tty_audit_exit(void)
373 {
374 }
375 static inline void tty_audit_fork(struct signal_struct *sig)
376 {
377 }
378 static inline void tty_audit_push(struct tty_struct *tty)
379 {
380 }
381 static inline void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid, u32 sessionid)
382 {
383 }
384 #endif
385 
386 /* tty_ioctl.c */
387 extern int n_tty_ioctl(struct tty_struct * tty, struct file * file,
388 		       unsigned int cmd, unsigned long arg);
389 
390 /* serial.c */
391 
392 extern void serial_console_init(void);
393 
394 /* pcxx.c */
395 
396 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
397 
398 /* printk.c */
399 
400 extern void console_print(const char *);
401 
402 /* vt.c */
403 
404 extern int vt_ioctl(struct tty_struct *tty, struct file * file,
405 		    unsigned int cmd, unsigned long arg);
406 
407 #endif /* __KERNEL__ */
408 #endif
409