1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_TTY_H
3 #define _LINUX_TTY_H
4
5 #include <linux/fs.h>
6 #include <linux/major.h>
7 #include <linux/termios.h>
8 #include <linux/workqueue.h>
9 #include <linux/tty_driver.h>
10 #include <linux/tty_ldisc.h>
11 #include <linux/mutex.h>
12 #include <linux/tty_flags.h>
13 #include <linux/seq_file.h>
14 #include <uapi/linux/tty.h>
15 #include <linux/rwsem.h>
16 #include <linux/llist.h>
17
18
19 /*
20 * Lock subclasses for tty locks
21 *
22 * TTY_LOCK_NORMAL is for normal ttys and master ptys.
23 * TTY_LOCK_SLAVE is for slave ptys only.
24 *
25 * Lock subclasses are necessary for handling nested locking with pty pairs.
26 * tty locks which use nested locking:
27 *
28 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
29 * The stable lock order is master pty first, then slave pty.
30 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
31 * Subclassing this lock enables the slave pty to hold its
32 * termios_rwsem when claiming the master tty_buffer lock.
33 * tty_buffer lock - slave ptys can claim nested buffer lock when handling
34 * signal chars. The stable lock order is slave pty, then
35 * master.
36 */
37
38 enum {
39 TTY_LOCK_NORMAL = 0,
40 TTY_LOCK_SLAVE,
41 };
42
43 /*
44 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
45 * hardcoded at present.)
46 */
47 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
48 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
49 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
50
51 /*
52 * This character is the same as _POSIX_VDISABLE: it cannot be used as
53 * a c_cc[] character, but indicates that a particular special character
54 * isn't in use (eg VINTR has no character etc)
55 */
56 #define __DISABLED_CHAR '\0'
57
58 struct tty_buffer {
59 union {
60 struct tty_buffer *next;
61 struct llist_node free;
62 };
63 int used;
64 int size;
65 int commit;
66 int read;
67 int flags;
68 /* Data points here */
69 unsigned long data[];
70 };
71
72 /* Values for .flags field of tty_buffer */
73 #define TTYB_NORMAL 1 /* buffer has no flags buffer */
74
char_buf_ptr(struct tty_buffer * b,int ofs)75 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs)
76 {
77 return ((unsigned char *)b->data) + ofs;
78 }
79
flag_buf_ptr(struct tty_buffer * b,int ofs)80 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs)
81 {
82 return (char *)char_buf_ptr(b, ofs) + b->size;
83 }
84
85 struct tty_bufhead {
86 struct tty_buffer *head; /* Queue head */
87 struct work_struct work;
88 struct mutex lock;
89 atomic_t priority;
90 struct tty_buffer sentinel;
91 struct llist_head free; /* Free queue head */
92 atomic_t mem_used; /* In-use buffers excluding free list */
93 int mem_limit;
94 struct tty_buffer *tail; /* Active buffer */
95 };
96 /*
97 * When a break, frame error, or parity error happens, these codes are
98 * stuffed into the flags buffer.
99 */
100 #define TTY_NORMAL 0
101 #define TTY_BREAK 1
102 #define TTY_FRAME 2
103 #define TTY_PARITY 3
104 #define TTY_OVERRUN 4
105
106 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
107 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
108 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
109 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
110 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
111 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
112 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
113 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
114 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
115 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
116 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
117 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
118 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
119 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
120 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
121 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
122 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
123
124 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
125 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
126 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
127 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
128
129 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
130 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
131 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
132 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
133 #define I_INPCK(tty) _I_FLAG((tty), INPCK)
134 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
135 #define I_INLCR(tty) _I_FLAG((tty), INLCR)
136 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
137 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
138 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
139 #define I_IXON(tty) _I_FLAG((tty), IXON)
140 #define I_IXANY(tty) _I_FLAG((tty), IXANY)
141 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
142 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
143 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
144
145 #define O_OPOST(tty) _O_FLAG((tty), OPOST)
146 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
147 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
148 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
149 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
150 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
151 #define O_OFILL(tty) _O_FLAG((tty), OFILL)
152 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
153 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
154 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
155 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
156 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
157 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
158 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
159
160 #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
161 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
162 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
163 #define C_CREAD(tty) _C_FLAG((tty), CREAD)
164 #define C_PARENB(tty) _C_FLAG((tty), PARENB)
165 #define C_PARODD(tty) _C_FLAG((tty), PARODD)
166 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
167 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
168 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
169 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
170 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR)
171
172 #define L_ISIG(tty) _L_FLAG((tty), ISIG)
173 #define L_ICANON(tty) _L_FLAG((tty), ICANON)
174 #define L_XCASE(tty) _L_FLAG((tty), XCASE)
175 #define L_ECHO(tty) _L_FLAG((tty), ECHO)
176 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
177 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
178 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
179 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
180 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
181 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
182 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
183 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
184 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
185 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
186 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
187 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
188
189 struct device;
190 struct signal_struct;
191
192 /*
193 * Port level information. Each device keeps its own port level information
194 * so provide a common structure for those ports wanting to use common support
195 * routines.
196 *
197 * The tty port has a different lifetime to the tty so must be kept apart.
198 * In addition be careful as tty -> port mappings are valid for the life
199 * of the tty object but in many cases port -> tty mappings are valid only
200 * until a hangup so don't use the wrong path.
201 */
202
203 struct tty_port;
204
205 struct tty_port_operations {
206 /* Return 1 if the carrier is raised */
207 int (*carrier_raised)(struct tty_port *port);
208 /* Control the DTR line */
209 void (*dtr_rts)(struct tty_port *port, int raise);
210 /* Called when the last close completes or a hangup finishes
211 IFF the port was initialized. Do not use to free resources. Called
212 under the port mutex to serialize against activate/shutdowns */
213 void (*shutdown)(struct tty_port *port);
214 /* Called under the port mutex from tty_port_open, serialized using
215 the port mutex */
216 /* FIXME: long term getting the tty argument *out* of this would be
217 good for consoles */
218 int (*activate)(struct tty_port *port, struct tty_struct *tty);
219 /* Called on the final put of a port */
220 void (*destruct)(struct tty_port *port);
221 };
222
223 struct tty_port_client_operations {
224 int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t);
225 void (*write_wakeup)(struct tty_port *port);
226 };
227
228 extern const struct tty_port_client_operations tty_port_default_client_ops;
229
230 struct tty_port {
231 struct tty_bufhead buf; /* Locked internally */
232 struct tty_struct *tty; /* Back pointer */
233 struct tty_struct *itty; /* internal back ptr */
234 const struct tty_port_operations *ops; /* Port operations */
235 const struct tty_port_client_operations *client_ops; /* Port client operations */
236 spinlock_t lock; /* Lock protecting tty field */
237 int blocked_open; /* Waiting to open */
238 int count; /* Usage count */
239 wait_queue_head_t open_wait; /* Open waiters */
240 wait_queue_head_t delta_msr_wait; /* Modem status change */
241 unsigned long flags; /* User TTY flags ASYNC_ */
242 unsigned long iflags; /* Internal flags TTY_PORT_ */
243 unsigned char console:1, /* port is a console */
244 low_latency:1; /* optional: tune for latency */
245 struct mutex mutex; /* Locking */
246 struct mutex buf_mutex; /* Buffer alloc lock */
247 unsigned char *xmit_buf; /* Optional buffer */
248 unsigned int close_delay; /* Close port delay */
249 unsigned int closing_wait; /* Delay for output */
250 int drain_delay; /* Set to zero if no pure time
251 based drain is needed else
252 set to size of fifo */
253 struct kref kref; /* Ref counter */
254 void *client_data;
255 };
256
257 /* tty_port::iflags bits -- use atomic bit ops */
258 #define TTY_PORT_INITIALIZED 0 /* device is initialized */
259 #define TTY_PORT_SUSPENDED 1 /* device is suspended */
260 #define TTY_PORT_ACTIVE 2 /* device is open */
261
262 /*
263 * uart drivers: use the uart_port::status field and the UPSTAT_* defines
264 * for s/w-based flow control steering and carrier detection status
265 */
266 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */
267 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */
268 #define TTY_PORT_KOPENED 5 /* device exclusively opened by
269 kernel */
270
271 /*
272 * Where all of the state associated with a tty is kept while the tty
273 * is open. Since the termios state should be kept even if the tty
274 * has been closed --- for things like the baud rate, etc --- it is
275 * not stored here, but rather a pointer to the real state is stored
276 * here. Possible the winsize structure should have the same
277 * treatment, but (1) the default 80x24 is usually right and (2) it's
278 * most often used by a windowing system, which will set the correct
279 * size each time the window is created or resized anyway.
280 * - TYT, 9/14/92
281 */
282
283 struct tty_operations;
284
285 struct tty_struct {
286 int magic;
287 struct kref kref;
288 struct device *dev;
289 struct tty_driver *driver;
290 const struct tty_operations *ops;
291 int index;
292
293 /* Protects ldisc changes: Lock tty not pty */
294 struct ld_semaphore ldisc_sem;
295 struct tty_ldisc *ldisc;
296
297 struct mutex atomic_write_lock;
298 struct mutex legacy_mutex;
299 struct mutex throttle_mutex;
300 struct rw_semaphore termios_rwsem;
301 struct mutex winsize_mutex;
302 spinlock_t ctrl_lock;
303 spinlock_t flow_lock;
304 /* Termios values are protected by the termios rwsem */
305 struct ktermios termios, termios_locked;
306 struct termiox *termiox; /* May be NULL for unsupported */
307 char name[64];
308 struct pid *pgrp; /* Protected by ctrl lock */
309 /*
310 * Writes protected by both ctrl lock and legacy mutex, readers must use
311 * at least one of them.
312 */
313 struct pid *session;
314 unsigned long flags;
315 int count;
316 struct winsize winsize; /* winsize_mutex */
317 unsigned long stopped:1, /* flow_lock */
318 flow_stopped:1,
319 unused:BITS_PER_LONG - 2;
320 int hw_stopped;
321 unsigned long ctrl_status:8, /* ctrl_lock */
322 packet:1,
323 unused_ctrl:BITS_PER_LONG - 9;
324 unsigned int receive_room; /* Bytes free for queue */
325 int flow_change;
326
327 struct tty_struct *link;
328 struct fasync_struct *fasync;
329 wait_queue_head_t write_wait;
330 wait_queue_head_t read_wait;
331 struct work_struct hangup_work;
332 void *disc_data;
333 void *driver_data;
334 spinlock_t files_lock; /* protects tty_files list */
335 struct list_head tty_files;
336
337 #define N_TTY_BUF_SIZE 4096
338
339 int closing;
340 unsigned char *write_buf;
341 int write_cnt;
342 /* If the tty has a pending do_SAK, queue it here - akpm */
343 struct work_struct SAK_work;
344 struct tty_port *port;
345 } __randomize_layout;
346
347 /* Each of a tty's open files has private_data pointing to tty_file_private */
348 struct tty_file_private {
349 struct tty_struct *tty;
350 struct file *file;
351 struct list_head list;
352 };
353
354 /* tty magic number */
355 #define TTY_MAGIC 0x5401
356
357 /*
358 * These bits are used in the flags field of the tty structure.
359 *
360 * So that interrupts won't be able to mess up the queues,
361 * copy_to_cooked must be atomic with respect to itself, as must
362 * tty->write. Thus, you must use the inline functions set_bit() and
363 * clear_bit() to make things atomic.
364 */
365 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
366 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
367 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
368 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
369 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
370 #define TTY_LDISC_OPEN 11 /* Line discipline is open */
371 #define TTY_PTY_LOCK 16 /* pty private */
372 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
373 #define TTY_HUPPED 18 /* Post driver->hangup() */
374 #define TTY_HUPPING 19 /* Hangup in progress */
375 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */
376 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */
377
378 /* Values for tty->flow_change */
379 #define TTY_THROTTLE_SAFE 1
380 #define TTY_UNTHROTTLE_SAFE 2
381
__tty_set_flow_change(struct tty_struct * tty,int val)382 static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
383 {
384 tty->flow_change = val;
385 }
386
tty_set_flow_change(struct tty_struct * tty,int val)387 static inline void tty_set_flow_change(struct tty_struct *tty, int val)
388 {
389 tty->flow_change = val;
390 smp_mb();
391 }
392
tty_io_nonblock(struct tty_struct * tty,struct file * file)393 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
394 {
395 return file->f_flags & O_NONBLOCK ||
396 test_bit(TTY_LDISC_CHANGING, &tty->flags);
397 }
398
tty_io_error(struct tty_struct * tty)399 static inline bool tty_io_error(struct tty_struct *tty)
400 {
401 return test_bit(TTY_IO_ERROR, &tty->flags);
402 }
403
tty_throttled(struct tty_struct * tty)404 static inline bool tty_throttled(struct tty_struct *tty)
405 {
406 return test_bit(TTY_THROTTLED, &tty->flags);
407 }
408
409 #ifdef CONFIG_TTY
410 extern void tty_kref_put(struct tty_struct *tty);
411 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
412 extern void tty_vhangup_self(void);
413 extern void disassociate_ctty(int priv);
414 extern dev_t tty_devnum(struct tty_struct *tty);
415 extern void proc_clear_tty(struct task_struct *p);
416 extern struct tty_struct *get_current_tty(void);
417 /* tty_io.c */
418 extern int __init tty_init(void);
419 extern const char *tty_name(const struct tty_struct *tty);
420 extern struct tty_struct *tty_kopen(dev_t device);
421 extern void tty_kclose(struct tty_struct *tty);
422 extern int tty_dev_name_to_number(const char *name, dev_t *number);
423 extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
424 extern void tty_ldisc_unlock(struct tty_struct *tty);
425 #else
tty_kref_put(struct tty_struct * tty)426 static inline void tty_kref_put(struct tty_struct *tty)
427 { }
tty_get_pgrp(struct tty_struct * tty)428 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
429 { return NULL; }
tty_vhangup_self(void)430 static inline void tty_vhangup_self(void)
431 { }
disassociate_ctty(int priv)432 static inline void disassociate_ctty(int priv)
433 { }
tty_devnum(struct tty_struct * tty)434 static inline dev_t tty_devnum(struct tty_struct *tty)
435 { return 0; }
proc_clear_tty(struct task_struct * p)436 static inline void proc_clear_tty(struct task_struct *p)
437 { }
get_current_tty(void)438 static inline struct tty_struct *get_current_tty(void)
439 { return NULL; }
440 /* tty_io.c */
tty_init(void)441 static inline int __init tty_init(void)
442 { return 0; }
tty_name(const struct tty_struct * tty)443 static inline const char *tty_name(const struct tty_struct *tty)
444 { return "(none)"; }
tty_kopen(dev_t device)445 static inline struct tty_struct *tty_kopen(dev_t device)
446 { return ERR_PTR(-ENODEV); }
tty_kclose(struct tty_struct * tty)447 static inline void tty_kclose(struct tty_struct *tty)
448 { }
tty_dev_name_to_number(const char * name,dev_t * number)449 static inline int tty_dev_name_to_number(const char *name, dev_t *number)
450 { return -ENOTSUPP; }
451 #endif
452
453 extern struct ktermios tty_std_termios;
454
455 extern int vcs_init(void);
456
457 extern struct class *tty_class;
458
459 /**
460 * tty_kref_get - get a tty reference
461 * @tty: tty device
462 *
463 * Return a new reference to a tty object. The caller must hold
464 * sufficient locks/counts to ensure that their existing reference cannot
465 * go away
466 */
467
tty_kref_get(struct tty_struct * tty)468 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
469 {
470 if (tty)
471 kref_get(&tty->kref);
472 return tty;
473 }
474
475 extern const char *tty_driver_name(const struct tty_struct *tty);
476 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
477 extern int __tty_check_change(struct tty_struct *tty, int sig);
478 extern int tty_check_change(struct tty_struct *tty);
479 extern void __stop_tty(struct tty_struct *tty);
480 extern void stop_tty(struct tty_struct *tty);
481 extern void __start_tty(struct tty_struct *tty);
482 extern void start_tty(struct tty_struct *tty);
483 void tty_write_unlock(struct tty_struct *tty);
484 int tty_write_lock(struct tty_struct *tty, int ndelay);
485 extern int tty_register_driver(struct tty_driver *driver);
486 extern int tty_unregister_driver(struct tty_driver *driver);
487 extern struct device *tty_register_device(struct tty_driver *driver,
488 unsigned index, struct device *dev);
489 extern struct device *tty_register_device_attr(struct tty_driver *driver,
490 unsigned index, struct device *device,
491 void *drvdata,
492 const struct attribute_group **attr_grp);
493 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
494 extern void tty_write_message(struct tty_struct *tty, char *msg);
495 extern int tty_send_xchar(struct tty_struct *tty, char ch);
496 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
497 extern int tty_chars_in_buffer(struct tty_struct *tty);
498 extern int tty_write_room(struct tty_struct *tty);
499 extern void tty_driver_flush_buffer(struct tty_struct *tty);
500 extern void tty_throttle(struct tty_struct *tty);
501 extern void tty_unthrottle(struct tty_struct *tty);
502 extern int tty_throttle_safe(struct tty_struct *tty);
503 extern int tty_unthrottle_safe(struct tty_struct *tty);
504 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
505 extern int is_current_pgrp_orphaned(void);
506 extern void tty_hangup(struct tty_struct *tty);
507 extern void tty_vhangup(struct tty_struct *tty);
508 extern void tty_vhangup_session(struct tty_struct *tty);
509 extern int tty_hung_up_p(struct file *filp);
510 extern void do_SAK(struct tty_struct *tty);
511 extern void __do_SAK(struct tty_struct *tty);
512 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
513 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
514 extern void session_clear_tty(struct pid *session);
515 extern void no_tty(void);
516 extern void tty_buffer_free_all(struct tty_port *port);
517 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
518 extern void tty_buffer_init(struct tty_port *port);
519 extern void tty_buffer_set_lock_subclass(struct tty_port *port);
520 extern bool tty_buffer_restart_work(struct tty_port *port);
521 extern bool tty_buffer_cancel_work(struct tty_port *port);
522 extern void tty_buffer_flush_work(struct tty_port *port);
523 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
524 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
525 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
526 speed_t ibaud, speed_t obaud);
527 extern void tty_encode_baud_rate(struct tty_struct *tty,
528 speed_t ibaud, speed_t obaud);
529
530 /**
531 * tty_get_baud_rate - get tty bit rates
532 * @tty: tty to query
533 *
534 * Returns the baud rate as an integer for this terminal. The
535 * termios lock must be held by the caller and the terminal bit
536 * flags may be updated.
537 *
538 * Locking: none
539 */
tty_get_baud_rate(struct tty_struct * tty)540 static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
541 {
542 return tty_termios_baud_rate(&tty->termios);
543 }
544
545 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
546 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
547 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
548
549 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
550 extern void tty_ldisc_deref(struct tty_ldisc *);
551 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
552 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset);
553 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc);
554 extern const struct seq_operations tty_ldiscs_seq_ops;
555
556 extern void tty_wakeup(struct tty_struct *tty);
557 extern void tty_ldisc_flush(struct tty_struct *tty);
558
559 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
560 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
561 unsigned int cmd, unsigned long arg);
562 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty,
563 struct file *file, unsigned int cmd, unsigned long arg);
564 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
565 extern void tty_default_fops(struct file_operations *fops);
566 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
567 extern int tty_alloc_file(struct file *file);
568 extern void tty_add_file(struct tty_struct *tty, struct file *file);
569 extern void tty_free_file(struct file *file);
570 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
571 extern void tty_release_struct(struct tty_struct *tty, int idx);
572 extern int tty_release(struct inode *inode, struct file *filp);
573 extern void tty_init_termios(struct tty_struct *tty);
574 extern void tty_save_termios(struct tty_struct *tty);
575 extern int tty_standard_install(struct tty_driver *driver,
576 struct tty_struct *tty);
577
578 extern struct mutex tty_mutex;
579
580 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
581
582 extern void tty_port_init(struct tty_port *port);
583 extern void tty_port_link_device(struct tty_port *port,
584 struct tty_driver *driver, unsigned index);
585 extern struct device *tty_port_register_device(struct tty_port *port,
586 struct tty_driver *driver, unsigned index,
587 struct device *device);
588 extern struct device *tty_port_register_device_attr(struct tty_port *port,
589 struct tty_driver *driver, unsigned index,
590 struct device *device, void *drvdata,
591 const struct attribute_group **attr_grp);
592 extern struct device *tty_port_register_device_serdev(struct tty_port *port,
593 struct tty_driver *driver, unsigned index,
594 struct device *device);
595 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
596 struct tty_driver *driver, unsigned index,
597 struct device *device, void *drvdata,
598 const struct attribute_group **attr_grp);
599 extern void tty_port_unregister_device(struct tty_port *port,
600 struct tty_driver *driver, unsigned index);
601 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
602 extern void tty_port_free_xmit_buf(struct tty_port *port);
603 extern void tty_port_destroy(struct tty_port *port);
604 extern void tty_port_put(struct tty_port *port);
605
tty_port_get(struct tty_port * port)606 static inline struct tty_port *tty_port_get(struct tty_port *port)
607 {
608 if (port && kref_get_unless_zero(&port->kref))
609 return port;
610 return NULL;
611 }
612
613 /* If the cts flow control is enabled, return true. */
tty_port_cts_enabled(struct tty_port * port)614 static inline bool tty_port_cts_enabled(struct tty_port *port)
615 {
616 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags);
617 }
618
tty_port_set_cts_flow(struct tty_port * port,bool val)619 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val)
620 {
621 if (val)
622 set_bit(TTY_PORT_CTS_FLOW, &port->iflags);
623 else
624 clear_bit(TTY_PORT_CTS_FLOW, &port->iflags);
625 }
626
tty_port_active(struct tty_port * port)627 static inline bool tty_port_active(struct tty_port *port)
628 {
629 return test_bit(TTY_PORT_ACTIVE, &port->iflags);
630 }
631
tty_port_set_active(struct tty_port * port,bool val)632 static inline void tty_port_set_active(struct tty_port *port, bool val)
633 {
634 if (val)
635 set_bit(TTY_PORT_ACTIVE, &port->iflags);
636 else
637 clear_bit(TTY_PORT_ACTIVE, &port->iflags);
638 }
639
tty_port_check_carrier(struct tty_port * port)640 static inline bool tty_port_check_carrier(struct tty_port *port)
641 {
642 return test_bit(TTY_PORT_CHECK_CD, &port->iflags);
643 }
644
tty_port_set_check_carrier(struct tty_port * port,bool val)645 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
646 {
647 if (val)
648 set_bit(TTY_PORT_CHECK_CD, &port->iflags);
649 else
650 clear_bit(TTY_PORT_CHECK_CD, &port->iflags);
651 }
652
tty_port_suspended(struct tty_port * port)653 static inline bool tty_port_suspended(struct tty_port *port)
654 {
655 return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
656 }
657
tty_port_set_suspended(struct tty_port * port,bool val)658 static inline void tty_port_set_suspended(struct tty_port *port, bool val)
659 {
660 if (val)
661 set_bit(TTY_PORT_SUSPENDED, &port->iflags);
662 else
663 clear_bit(TTY_PORT_SUSPENDED, &port->iflags);
664 }
665
tty_port_initialized(struct tty_port * port)666 static inline bool tty_port_initialized(struct tty_port *port)
667 {
668 return test_bit(TTY_PORT_INITIALIZED, &port->iflags);
669 }
670
tty_port_set_initialized(struct tty_port * port,bool val)671 static inline void tty_port_set_initialized(struct tty_port *port, bool val)
672 {
673 if (val)
674 set_bit(TTY_PORT_INITIALIZED, &port->iflags);
675 else
676 clear_bit(TTY_PORT_INITIALIZED, &port->iflags);
677 }
678
tty_port_kopened(struct tty_port * port)679 static inline bool tty_port_kopened(struct tty_port *port)
680 {
681 return test_bit(TTY_PORT_KOPENED, &port->iflags);
682 }
683
tty_port_set_kopened(struct tty_port * port,bool val)684 static inline void tty_port_set_kopened(struct tty_port *port, bool val)
685 {
686 if (val)
687 set_bit(TTY_PORT_KOPENED, &port->iflags);
688 else
689 clear_bit(TTY_PORT_KOPENED, &port->iflags);
690 }
691
692 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
693 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
694 extern int tty_port_carrier_raised(struct tty_port *port);
695 extern void tty_port_raise_dtr_rts(struct tty_port *port);
696 extern void tty_port_lower_dtr_rts(struct tty_port *port);
697 extern void tty_port_hangup(struct tty_port *port);
698 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
699 extern void tty_port_tty_wakeup(struct tty_port *port);
700 extern int tty_port_block_til_ready(struct tty_port *port,
701 struct tty_struct *tty, struct file *filp);
702 extern int tty_port_close_start(struct tty_port *port,
703 struct tty_struct *tty, struct file *filp);
704 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
705 extern void tty_port_close(struct tty_port *port,
706 struct tty_struct *tty, struct file *filp);
707 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
708 struct tty_struct *tty);
709 extern int tty_port_open(struct tty_port *port,
710 struct tty_struct *tty, struct file *filp);
tty_port_users(struct tty_port * port)711 static inline int tty_port_users(struct tty_port *port)
712 {
713 return port->count + port->blocked_open;
714 }
715
716 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
717 extern int tty_unregister_ldisc(int disc);
718 extern int tty_set_ldisc(struct tty_struct *tty, int disc);
719 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
720 extern void tty_ldisc_release(struct tty_struct *tty);
721 extern int __must_check tty_ldisc_init(struct tty_struct *tty);
722 extern void tty_ldisc_deinit(struct tty_struct *tty);
723 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
724 char *f, int count);
725
726 /* n_tty.c */
727 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
728 #ifdef CONFIG_TTY
729 extern void __init n_tty_init(void);
730 #else
n_tty_init(void)731 static inline void n_tty_init(void) { }
732 #endif
733
734 /* tty_audit.c */
735 #ifdef CONFIG_AUDIT
736 extern void tty_audit_add_data(struct tty_struct *tty, const void *data,
737 size_t size);
738 extern void tty_audit_exit(void);
739 extern void tty_audit_fork(struct signal_struct *sig);
740 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
741 extern int tty_audit_push(void);
742 #else
tty_audit_add_data(struct tty_struct * tty,const void * data,size_t size)743 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data,
744 size_t size)
745 {
746 }
tty_audit_tiocsti(struct tty_struct * tty,char ch)747 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
748 {
749 }
tty_audit_exit(void)750 static inline void tty_audit_exit(void)
751 {
752 }
tty_audit_fork(struct signal_struct * sig)753 static inline void tty_audit_fork(struct signal_struct *sig)
754 {
755 }
tty_audit_push(void)756 static inline int tty_audit_push(void)
757 {
758 return 0;
759 }
760 #endif
761
762 /* tty_ioctl.c */
763 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
764 unsigned int cmd, unsigned long arg);
765 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
766 unsigned int cmd, unsigned long arg);
767
768 /* vt.c */
769
770 extern int vt_ioctl(struct tty_struct *tty,
771 unsigned int cmd, unsigned long arg);
772
773 extern long vt_compat_ioctl(struct tty_struct *tty,
774 unsigned int cmd, unsigned long arg);
775
776 /* tty_mutex.c */
777 /* functions for preparation of BKL removal */
778 extern void tty_lock(struct tty_struct *tty);
779 extern int tty_lock_interruptible(struct tty_struct *tty);
780 extern void tty_unlock(struct tty_struct *tty);
781 extern void tty_lock_slave(struct tty_struct *tty);
782 extern void tty_unlock_slave(struct tty_struct *tty);
783 extern void tty_set_lock_subclass(struct tty_struct *tty);
784
785 #ifdef CONFIG_PROC_FS
786 extern void proc_tty_register_driver(struct tty_driver *);
787 extern void proc_tty_unregister_driver(struct tty_driver *);
788 #else
proc_tty_register_driver(struct tty_driver * d)789 static inline void proc_tty_register_driver(struct tty_driver *d) {}
proc_tty_unregister_driver(struct tty_driver * d)790 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
791 #endif
792
793 #define tty_msg(fn, tty, f, ...) \
794 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__)
795
796 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__)
797 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__)
798 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__)
799 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__)
800 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__)
801
802 #define tty_info_ratelimited(tty, f, ...) \
803 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__)
804
805 #endif
806