xref: /linux-6.15/include/linux/tty.h (revision 40efcb05)
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		17
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 
48 /*
49  * This character is the same as _POSIX_VDISABLE: it cannot be used as
50  * a c_cc[] character, but indicates that a particular special character
51  * isn't in use (eg VINTR has no character etc)
52  */
53 #define __DISABLED_CHAR '\0'
54 
55 /*
56  * This is the flip buffer used for the tty driver.  The buffer is
57  * located in the tty structure, and is used as a high speed interface
58  * between the tty driver and the tty line discipline.
59  */
60 #define TTY_FLIPBUF_SIZE 512
61 
62 struct tty_buffer {
63 	struct tty_buffer *next;
64 	char *char_buf_ptr;
65 	unsigned char *flag_buf_ptr;
66 	int used;
67 	int size;
68 	int commit;
69 	int read;
70 	/* Data points here */
71 	unsigned long data[0];
72 };
73 
74 struct tty_bufhead {
75 	struct delayed_work work;
76 	struct semaphore pty_sem;
77 	spinlock_t lock;
78 	struct tty_buffer *head;	/* Queue head */
79 	struct tty_buffer *tail;	/* Active buffer */
80 	struct tty_buffer *free;	/* Free queue head */
81 	int memory_used;		/* Buffer space used excluding free queue */
82 };
83 /*
84  * When a break, frame error, or parity error happens, these codes are
85  * stuffed into the flags buffer.
86  */
87 #define TTY_NORMAL	0
88 #define TTY_BREAK	1
89 #define TTY_FRAME	2
90 #define TTY_PARITY	3
91 #define TTY_OVERRUN	4
92 
93 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
94 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
95 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
96 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
97 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
98 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
99 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
100 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
101 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
102 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
103 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
104 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
105 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
106 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
107 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
108 #define LNEXT_CHAR(tty)	((tty)->termios->c_cc[VLNEXT])
109 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
110 
111 #define _I_FLAG(tty,f)	((tty)->termios->c_iflag & (f))
112 #define _O_FLAG(tty,f)	((tty)->termios->c_oflag & (f))
113 #define _C_FLAG(tty,f)	((tty)->termios->c_cflag & (f))
114 #define _L_FLAG(tty,f)	((tty)->termios->c_lflag & (f))
115 
116 #define I_IGNBRK(tty)	_I_FLAG((tty),IGNBRK)
117 #define I_BRKINT(tty)	_I_FLAG((tty),BRKINT)
118 #define I_IGNPAR(tty)	_I_FLAG((tty),IGNPAR)
119 #define I_PARMRK(tty)	_I_FLAG((tty),PARMRK)
120 #define I_INPCK(tty)	_I_FLAG((tty),INPCK)
121 #define I_ISTRIP(tty)	_I_FLAG((tty),ISTRIP)
122 #define I_INLCR(tty)	_I_FLAG((tty),INLCR)
123 #define I_IGNCR(tty)	_I_FLAG((tty),IGNCR)
124 #define I_ICRNL(tty)	_I_FLAG((tty),ICRNL)
125 #define I_IUCLC(tty)	_I_FLAG((tty),IUCLC)
126 #define I_IXON(tty)	_I_FLAG((tty),IXON)
127 #define I_IXANY(tty)	_I_FLAG((tty),IXANY)
128 #define I_IXOFF(tty)	_I_FLAG((tty),IXOFF)
129 #define I_IMAXBEL(tty)	_I_FLAG((tty),IMAXBEL)
130 #define I_IUTF8(tty)	_I_FLAG((tty),IUTF8)
131 
132 #define O_OPOST(tty)	_O_FLAG((tty),OPOST)
133 #define O_OLCUC(tty)	_O_FLAG((tty),OLCUC)
134 #define O_ONLCR(tty)	_O_FLAG((tty),ONLCR)
135 #define O_OCRNL(tty)	_O_FLAG((tty),OCRNL)
136 #define O_ONOCR(tty)	_O_FLAG((tty),ONOCR)
137 #define O_ONLRET(tty)	_O_FLAG((tty),ONLRET)
138 #define O_OFILL(tty)	_O_FLAG((tty),OFILL)
139 #define O_OFDEL(tty)	_O_FLAG((tty),OFDEL)
140 #define O_NLDLY(tty)	_O_FLAG((tty),NLDLY)
141 #define O_CRDLY(tty)	_O_FLAG((tty),CRDLY)
142 #define O_TABDLY(tty)	_O_FLAG((tty),TABDLY)
143 #define O_BSDLY(tty)	_O_FLAG((tty),BSDLY)
144 #define O_VTDLY(tty)	_O_FLAG((tty),VTDLY)
145 #define O_FFDLY(tty)	_O_FLAG((tty),FFDLY)
146 
147 #define C_BAUD(tty)	_C_FLAG((tty),CBAUD)
148 #define C_CSIZE(tty)	_C_FLAG((tty),CSIZE)
149 #define C_CSTOPB(tty)	_C_FLAG((tty),CSTOPB)
150 #define C_CREAD(tty)	_C_FLAG((tty),CREAD)
151 #define C_PARENB(tty)	_C_FLAG((tty),PARENB)
152 #define C_PARODD(tty)	_C_FLAG((tty),PARODD)
153 #define C_HUPCL(tty)	_C_FLAG((tty),HUPCL)
154 #define C_CLOCAL(tty)	_C_FLAG((tty),CLOCAL)
155 #define C_CIBAUD(tty)	_C_FLAG((tty),CIBAUD)
156 #define C_CRTSCTS(tty)	_C_FLAG((tty),CRTSCTS)
157 
158 #define L_ISIG(tty)	_L_FLAG((tty),ISIG)
159 #define L_ICANON(tty)	_L_FLAG((tty),ICANON)
160 #define L_XCASE(tty)	_L_FLAG((tty),XCASE)
161 #define L_ECHO(tty)	_L_FLAG((tty),ECHO)
162 #define L_ECHOE(tty)	_L_FLAG((tty),ECHOE)
163 #define L_ECHOK(tty)	_L_FLAG((tty),ECHOK)
164 #define L_ECHONL(tty)	_L_FLAG((tty),ECHONL)
165 #define L_NOFLSH(tty)	_L_FLAG((tty),NOFLSH)
166 #define L_TOSTOP(tty)	_L_FLAG((tty),TOSTOP)
167 #define L_ECHOCTL(tty)	_L_FLAG((tty),ECHOCTL)
168 #define L_ECHOPRT(tty)	_L_FLAG((tty),ECHOPRT)
169 #define L_ECHOKE(tty)	_L_FLAG((tty),ECHOKE)
170 #define L_FLUSHO(tty)	_L_FLAG((tty),FLUSHO)
171 #define L_PENDIN(tty)	_L_FLAG((tty),PENDIN)
172 #define L_IEXTEN(tty)	_L_FLAG((tty),IEXTEN)
173 
174 struct device;
175 struct signal_struct;
176 /*
177  * Where all of the state associated with a tty is kept while the tty
178  * is open.  Since the termios state should be kept even if the tty
179  * has been closed --- for things like the baud rate, etc --- it is
180  * not stored here, but rather a pointer to the real state is stored
181  * here.  Possible the winsize structure should have the same
182  * treatment, but (1) the default 80x24 is usually right and (2) it's
183  * most often used by a windowing system, which will set the correct
184  * size each time the window is created or resized anyway.
185  * 						- TYT, 9/14/92
186  */
187 struct tty_struct {
188 	int	magic;
189 	struct tty_driver *driver;
190 	int index;
191 	struct tty_ldisc ldisc;
192 	struct mutex termios_mutex;
193 	struct ktermios *termios, *termios_locked;
194 	char name[64];
195 	struct pid *pgrp;
196 	struct pid *session;
197 	unsigned long flags;
198 	int count;
199 	struct winsize winsize;
200 	unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
201 	unsigned char low_latency:1, warned:1;
202 	unsigned char ctrl_status;
203 	unsigned int receive_room;	/* Bytes free for queue */
204 
205 	struct tty_struct *link;
206 	struct fasync_struct *fasync;
207 	struct tty_bufhead buf;
208 	int alt_speed;		/* For magic substitution of 38400 bps */
209 	wait_queue_head_t write_wait;
210 	wait_queue_head_t read_wait;
211 	struct work_struct hangup_work;
212 	void *disc_data;
213 	void *driver_data;
214 	struct list_head tty_files;
215 
216 #define N_TTY_BUF_SIZE 4096
217 
218 	/*
219 	 * The following is data for the N_TTY line discipline.  For
220 	 * historical reasons, this is included in the tty structure.
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 
303 extern int is_current_pgrp_orphaned(void);
304 extern int is_ignored(int sig);
305 extern int tty_signal(int sig, struct tty_struct *tty);
306 extern void tty_hangup(struct tty_struct * tty);
307 extern void tty_vhangup(struct tty_struct * tty);
308 extern void tty_unhangup(struct file *filp);
309 extern int tty_hung_up_p(struct file * filp);
310 extern int is_tty(struct file *filp);
311 extern void do_SAK(struct tty_struct *tty);
312 extern void __do_SAK(struct tty_struct *tty);
313 extern void disassociate_ctty(int priv);
314 extern void no_tty(void);
315 extern void tty_flip_buffer_push(struct tty_struct *tty);
316 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
317 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
318 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
319 extern void tty_termios_encode_baud_rate(struct ktermios *termios, speed_t ibaud, speed_t obaud);
320 extern void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud);
321 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
322 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
323 
324 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
325 extern void tty_ldisc_deref(struct tty_ldisc *);
326 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
327 
328 extern struct tty_ldisc *tty_ldisc_get(int);
329 extern void tty_ldisc_put(int);
330 
331 extern void tty_wakeup(struct tty_struct *tty);
332 extern void tty_ldisc_flush(struct tty_struct *tty);
333 
334 extern int tty_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
335 		     unsigned long arg);
336 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
337 			unsigned int cmd, unsigned long arg);
338 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
339 extern dev_t tty_devnum(struct tty_struct *tty);
340 extern void proc_clear_tty(struct task_struct *p);
341 extern struct tty_struct *get_current_tty(void);
342 
343 extern struct mutex tty_mutex;
344 
345 extern void tty_write_unlock(struct tty_struct *tty);
346 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
347 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
348 
349 
350 
351 /* n_tty.c */
352 extern struct tty_ldisc tty_ldisc_N_TTY;
353 
354 /* tty_audit.c */
355 #ifdef CONFIG_AUDIT
356 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
357 			       size_t size);
358 extern void tty_audit_exit(void);
359 extern void tty_audit_fork(struct signal_struct *sig);
360 extern void tty_audit_push(struct tty_struct *tty);
361 extern void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid);
362 extern void tty_audit_opening(void);
363 #else
364 static inline void tty_audit_add_data(struct tty_struct *tty,
365 				      unsigned char *data, size_t size)
366 {
367 }
368 static inline void tty_audit_exit(void)
369 {
370 }
371 static inline void tty_audit_fork(struct signal_struct *sig)
372 {
373 }
374 static inline void tty_audit_push(struct tty_struct *tty)
375 {
376 }
377 static inline void tty_audit_push_task(struct task_struct *tsk, uid_t loginuid)
378 {
379 }
380 static inline void tty_audit_opening(void)
381 {
382 }
383 #endif
384 
385 /* tty_ioctl.c */
386 extern int n_tty_ioctl(struct tty_struct * tty, struct file * file,
387 		       unsigned int cmd, unsigned long arg);
388 
389 /* serial.c */
390 
391 extern void serial_console_init(void);
392 
393 /* pcxx.c */
394 
395 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
396 
397 /* printk.c */
398 
399 extern void console_print(const char *);
400 
401 /* vt.c */
402 
403 extern int vt_ioctl(struct tty_struct *tty, struct file * file,
404 		    unsigned int cmd, unsigned long arg);
405 
406 #endif /* __KERNEL__ */
407 #endif
408