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[0];
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 struct tty_port {
229 struct tty_bufhead buf; /* Locked internally */
230 struct tty_struct *tty; /* Back pointer */
231 struct tty_struct *itty; /* internal back ptr */
232 const struct tty_port_operations *ops; /* Port operations */
233 const struct tty_port_client_operations *client_ops; /* Port client operations */
234 spinlock_t lock; /* Lock protecting tty field */
235 int blocked_open; /* Waiting to open */
236 int count; /* Usage count */
237 wait_queue_head_t open_wait; /* Open waiters */
238 wait_queue_head_t delta_msr_wait; /* Modem status change */
239 unsigned long flags; /* User TTY flags ASYNC_ */
240 unsigned long iflags; /* Internal flags TTY_PORT_ */
241 unsigned char console:1, /* port is a console */
242 low_latency:1; /* optional: tune for latency */
243 struct mutex mutex; /* Locking */
244 struct mutex buf_mutex; /* Buffer alloc lock */
245 unsigned char *xmit_buf; /* Optional buffer */
246 unsigned int close_delay; /* Close port delay */
247 unsigned int closing_wait; /* Delay for output */
248 int drain_delay; /* Set to zero if no pure time
249 based drain is needed else
250 set to size of fifo */
251 struct kref kref; /* Ref counter */
252 void *client_data;
253 };
254
255 /* tty_port::iflags bits -- use atomic bit ops */
256 #define TTY_PORT_INITIALIZED 0 /* device is initialized */
257 #define TTY_PORT_SUSPENDED 1 /* device is suspended */
258 #define TTY_PORT_ACTIVE 2 /* device is open */
259
260 /*
261 * uart drivers: use the uart_port::status field and the UPSTAT_* defines
262 * for s/w-based flow control steering and carrier detection status
263 */
264 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */
265 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */
266 #define TTY_PORT_KOPENED 5 /* device exclusively opened by
267 kernel */
268
269 /*
270 * Where all of the state associated with a tty is kept while the tty
271 * is open. Since the termios state should be kept even if the tty
272 * has been closed --- for things like the baud rate, etc --- it is
273 * not stored here, but rather a pointer to the real state is stored
274 * here. Possible the winsize structure should have the same
275 * treatment, but (1) the default 80x24 is usually right and (2) it's
276 * most often used by a windowing system, which will set the correct
277 * size each time the window is created or resized anyway.
278 * - TYT, 9/14/92
279 */
280
281 struct tty_operations;
282
283 struct tty_struct {
284 int magic;
285 struct kref kref;
286 struct device *dev;
287 struct tty_driver *driver;
288 const struct tty_operations *ops;
289 int index;
290
291 /* Protects ldisc changes: Lock tty not pty */
292 struct ld_semaphore ldisc_sem;
293 struct tty_ldisc *ldisc;
294
295 struct mutex atomic_write_lock;
296 struct mutex legacy_mutex;
297 struct mutex throttle_mutex;
298 struct rw_semaphore termios_rwsem;
299 struct mutex winsize_mutex;
300 spinlock_t ctrl_lock;
301 spinlock_t flow_lock;
302 /* Termios values are protected by the termios rwsem */
303 struct ktermios termios, termios_locked;
304 struct termiox *termiox; /* May be NULL for unsupported */
305 char name[64];
306 struct pid *pgrp; /* Protected by ctrl lock */
307 struct pid *session;
308 unsigned long flags;
309 int count;
310 struct winsize winsize; /* winsize_mutex */
311 unsigned long stopped:1, /* flow_lock */
312 flow_stopped:1,
313 unused:BITS_PER_LONG - 2;
314 int hw_stopped;
315 unsigned long ctrl_status:8, /* ctrl_lock */
316 packet:1,
317 unused_ctrl:BITS_PER_LONG - 9;
318 unsigned int receive_room; /* Bytes free for queue */
319 int flow_change;
320
321 struct tty_struct *link;
322 struct fasync_struct *fasync;
323 wait_queue_head_t write_wait;
324 wait_queue_head_t read_wait;
325 struct work_struct hangup_work;
326 void *disc_data;
327 void *driver_data;
328 spinlock_t files_lock; /* protects tty_files list */
329 struct list_head tty_files;
330
331 #define N_TTY_BUF_SIZE 4096
332
333 int closing;
334 unsigned char *write_buf;
335 int write_cnt;
336 /* If the tty has a pending do_SAK, queue it here - akpm */
337 struct work_struct SAK_work;
338 struct tty_port *port;
339 } __randomize_layout;
340
341 /* Each of a tty's open files has private_data pointing to tty_file_private */
342 struct tty_file_private {
343 struct tty_struct *tty;
344 struct file *file;
345 struct list_head list;
346 };
347
348 /* tty magic number */
349 #define TTY_MAGIC 0x5401
350
351 /*
352 * These bits are used in the flags field of the tty structure.
353 *
354 * So that interrupts won't be able to mess up the queues,
355 * copy_to_cooked must be atomic with respect to itself, as must
356 * tty->write. Thus, you must use the inline functions set_bit() and
357 * clear_bit() to make things atomic.
358 */
359 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
360 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
361 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
362 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
363 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
364 #define TTY_LDISC_OPEN 11 /* Line discipline is open */
365 #define TTY_PTY_LOCK 16 /* pty private */
366 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
367 #define TTY_HUPPED 18 /* Post driver->hangup() */
368 #define TTY_HUPPING 19 /* Hangup in progress */
369 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */
370
371 /* Values for tty->flow_change */
372 #define TTY_THROTTLE_SAFE 1
373 #define TTY_UNTHROTTLE_SAFE 2
374
__tty_set_flow_change(struct tty_struct * tty,int val)375 static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
376 {
377 tty->flow_change = val;
378 }
379
tty_set_flow_change(struct tty_struct * tty,int val)380 static inline void tty_set_flow_change(struct tty_struct *tty, int val)
381 {
382 tty->flow_change = val;
383 smp_mb();
384 }
385
tty_io_error(struct tty_struct * tty)386 static inline bool tty_io_error(struct tty_struct *tty)
387 {
388 return test_bit(TTY_IO_ERROR, &tty->flags);
389 }
390
tty_throttled(struct tty_struct * tty)391 static inline bool tty_throttled(struct tty_struct *tty)
392 {
393 return test_bit(TTY_THROTTLED, &tty->flags);
394 }
395
396 #ifdef CONFIG_TTY
397 extern void tty_kref_put(struct tty_struct *tty);
398 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
399 extern void tty_vhangup_self(void);
400 extern void disassociate_ctty(int priv);
401 extern dev_t tty_devnum(struct tty_struct *tty);
402 extern void proc_clear_tty(struct task_struct *p);
403 extern struct tty_struct *get_current_tty(void);
404 /* tty_io.c */
405 extern int __init tty_init(void);
406 extern const char *tty_name(const struct tty_struct *tty);
407 extern struct tty_struct *tty_kopen(dev_t device);
408 extern void tty_kclose(struct tty_struct *tty);
409 extern int tty_dev_name_to_number(const char *name, dev_t *number);
410 extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
411 extern void tty_ldisc_unlock(struct tty_struct *tty);
412 #else
tty_kref_put(struct tty_struct * tty)413 static inline void tty_kref_put(struct tty_struct *tty)
414 { }
tty_get_pgrp(struct tty_struct * tty)415 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
416 { return NULL; }
tty_vhangup_self(void)417 static inline void tty_vhangup_self(void)
418 { }
disassociate_ctty(int priv)419 static inline void disassociate_ctty(int priv)
420 { }
tty_devnum(struct tty_struct * tty)421 static inline dev_t tty_devnum(struct tty_struct *tty)
422 { return 0; }
proc_clear_tty(struct task_struct * p)423 static inline void proc_clear_tty(struct task_struct *p)
424 { }
get_current_tty(void)425 static inline struct tty_struct *get_current_tty(void)
426 { return NULL; }
427 /* tty_io.c */
tty_init(void)428 static inline int __init tty_init(void)
429 { return 0; }
tty_name(const struct tty_struct * tty)430 static inline const char *tty_name(const struct tty_struct *tty)
431 { return "(none)"; }
tty_kopen(dev_t device)432 static inline struct tty_struct *tty_kopen(dev_t device)
433 { return ERR_PTR(-ENODEV); }
tty_kclose(struct tty_struct * tty)434 static inline void tty_kclose(struct tty_struct *tty)
435 { }
tty_dev_name_to_number(const char * name,dev_t * number)436 static inline int tty_dev_name_to_number(const char *name, dev_t *number)
437 { return -ENOTSUPP; }
438 #endif
439
440 extern struct ktermios tty_std_termios;
441
442 extern int vcs_init(void);
443
444 extern struct class *tty_class;
445
446 /**
447 * tty_kref_get - get a tty reference
448 * @tty: tty device
449 *
450 * Return a new reference to a tty object. The caller must hold
451 * sufficient locks/counts to ensure that their existing reference cannot
452 * go away
453 */
454
tty_kref_get(struct tty_struct * tty)455 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
456 {
457 if (tty)
458 kref_get(&tty->kref);
459 return tty;
460 }
461
462 extern const char *tty_driver_name(const struct tty_struct *tty);
463 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
464 extern int __tty_check_change(struct tty_struct *tty, int sig);
465 extern int tty_check_change(struct tty_struct *tty);
466 extern void __stop_tty(struct tty_struct *tty);
467 extern void stop_tty(struct tty_struct *tty);
468 extern void __start_tty(struct tty_struct *tty);
469 extern void start_tty(struct tty_struct *tty);
470 extern int tty_register_driver(struct tty_driver *driver);
471 extern int tty_unregister_driver(struct tty_driver *driver);
472 extern struct device *tty_register_device(struct tty_driver *driver,
473 unsigned index, struct device *dev);
474 extern struct device *tty_register_device_attr(struct tty_driver *driver,
475 unsigned index, struct device *device,
476 void *drvdata,
477 const struct attribute_group **attr_grp);
478 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
479 extern void tty_write_message(struct tty_struct *tty, char *msg);
480 extern int tty_send_xchar(struct tty_struct *tty, char ch);
481 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
482 extern int tty_chars_in_buffer(struct tty_struct *tty);
483 extern int tty_write_room(struct tty_struct *tty);
484 extern void tty_driver_flush_buffer(struct tty_struct *tty);
485 extern void tty_throttle(struct tty_struct *tty);
486 extern void tty_unthrottle(struct tty_struct *tty);
487 extern int tty_throttle_safe(struct tty_struct *tty);
488 extern int tty_unthrottle_safe(struct tty_struct *tty);
489 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
490 extern int is_current_pgrp_orphaned(void);
491 extern void tty_hangup(struct tty_struct *tty);
492 extern void tty_vhangup(struct tty_struct *tty);
493 extern void tty_vhangup_session(struct tty_struct *tty);
494 extern int tty_hung_up_p(struct file *filp);
495 extern void do_SAK(struct tty_struct *tty);
496 extern void __do_SAK(struct tty_struct *tty);
497 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty);
498 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session);
499 extern void session_clear_tty(struct pid *session);
500 extern void no_tty(void);
501 extern void tty_buffer_free_all(struct tty_port *port);
502 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
503 extern void tty_buffer_init(struct tty_port *port);
504 extern void tty_buffer_set_lock_subclass(struct tty_port *port);
505 extern bool tty_buffer_restart_work(struct tty_port *port);
506 extern bool tty_buffer_cancel_work(struct tty_port *port);
507 extern void tty_buffer_flush_work(struct tty_port *port);
508 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
509 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
510 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
511 speed_t ibaud, speed_t obaud);
512 extern void tty_encode_baud_rate(struct tty_struct *tty,
513 speed_t ibaud, speed_t obaud);
514
515 /**
516 * tty_get_baud_rate - get tty bit rates
517 * @tty: tty to query
518 *
519 * Returns the baud rate as an integer for this terminal. The
520 * termios lock must be held by the caller and the terminal bit
521 * flags may be updated.
522 *
523 * Locking: none
524 */
tty_get_baud_rate(struct tty_struct * tty)525 static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
526 {
527 return tty_termios_baud_rate(&tty->termios);
528 }
529
530 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
531 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
532 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
533
534 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
535 extern void tty_ldisc_deref(struct tty_ldisc *);
536 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
537 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset);
538 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc);
539 extern const struct seq_operations tty_ldiscs_seq_ops;
540
541 extern void tty_wakeup(struct tty_struct *tty);
542 extern void tty_ldisc_flush(struct tty_struct *tty);
543
544 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
545 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
546 unsigned int cmd, unsigned long arg);
547 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty,
548 struct file *file, unsigned int cmd, unsigned long arg);
549 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
550 extern void tty_default_fops(struct file_operations *fops);
551 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
552 extern int tty_alloc_file(struct file *file);
553 extern void tty_add_file(struct tty_struct *tty, struct file *file);
554 extern void tty_free_file(struct file *file);
555 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
556 extern void tty_release_struct(struct tty_struct *tty, int idx);
557 extern int tty_release(struct inode *inode, struct file *filp);
558 extern void tty_init_termios(struct tty_struct *tty);
559 extern int tty_standard_install(struct tty_driver *driver,
560 struct tty_struct *tty);
561
562 extern struct mutex tty_mutex;
563
564 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
565
566 extern void tty_port_init(struct tty_port *port);
567 extern void tty_port_link_device(struct tty_port *port,
568 struct tty_driver *driver, unsigned index);
569 extern struct device *tty_port_register_device(struct tty_port *port,
570 struct tty_driver *driver, unsigned index,
571 struct device *device);
572 extern struct device *tty_port_register_device_attr(struct tty_port *port,
573 struct tty_driver *driver, unsigned index,
574 struct device *device, void *drvdata,
575 const struct attribute_group **attr_grp);
576 extern struct device *tty_port_register_device_serdev(struct tty_port *port,
577 struct tty_driver *driver, unsigned index,
578 struct device *device);
579 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port,
580 struct tty_driver *driver, unsigned index,
581 struct device *device, void *drvdata,
582 const struct attribute_group **attr_grp);
583 extern void tty_port_unregister_device(struct tty_port *port,
584 struct tty_driver *driver, unsigned index);
585 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
586 extern void tty_port_free_xmit_buf(struct tty_port *port);
587 extern void tty_port_destroy(struct tty_port *port);
588 extern void tty_port_put(struct tty_port *port);
589
tty_port_get(struct tty_port * port)590 static inline struct tty_port *tty_port_get(struct tty_port *port)
591 {
592 if (port && kref_get_unless_zero(&port->kref))
593 return port;
594 return NULL;
595 }
596
597 /* If the cts flow control is enabled, return true. */
tty_port_cts_enabled(struct tty_port * port)598 static inline bool tty_port_cts_enabled(struct tty_port *port)
599 {
600 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags);
601 }
602
tty_port_set_cts_flow(struct tty_port * port,bool val)603 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val)
604 {
605 if (val)
606 set_bit(TTY_PORT_CTS_FLOW, &port->iflags);
607 else
608 clear_bit(TTY_PORT_CTS_FLOW, &port->iflags);
609 }
610
tty_port_active(struct tty_port * port)611 static inline bool tty_port_active(struct tty_port *port)
612 {
613 return test_bit(TTY_PORT_ACTIVE, &port->iflags);
614 }
615
tty_port_set_active(struct tty_port * port,bool val)616 static inline void tty_port_set_active(struct tty_port *port, bool val)
617 {
618 if (val)
619 set_bit(TTY_PORT_ACTIVE, &port->iflags);
620 else
621 clear_bit(TTY_PORT_ACTIVE, &port->iflags);
622 }
623
tty_port_check_carrier(struct tty_port * port)624 static inline bool tty_port_check_carrier(struct tty_port *port)
625 {
626 return test_bit(TTY_PORT_CHECK_CD, &port->iflags);
627 }
628
tty_port_set_check_carrier(struct tty_port * port,bool val)629 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val)
630 {
631 if (val)
632 set_bit(TTY_PORT_CHECK_CD, &port->iflags);
633 else
634 clear_bit(TTY_PORT_CHECK_CD, &port->iflags);
635 }
636
tty_port_suspended(struct tty_port * port)637 static inline bool tty_port_suspended(struct tty_port *port)
638 {
639 return test_bit(TTY_PORT_SUSPENDED, &port->iflags);
640 }
641
tty_port_set_suspended(struct tty_port * port,bool val)642 static inline void tty_port_set_suspended(struct tty_port *port, bool val)
643 {
644 if (val)
645 set_bit(TTY_PORT_SUSPENDED, &port->iflags);
646 else
647 clear_bit(TTY_PORT_SUSPENDED, &port->iflags);
648 }
649
tty_port_initialized(struct tty_port * port)650 static inline bool tty_port_initialized(struct tty_port *port)
651 {
652 return test_bit(TTY_PORT_INITIALIZED, &port->iflags);
653 }
654
tty_port_set_initialized(struct tty_port * port,bool val)655 static inline void tty_port_set_initialized(struct tty_port *port, bool val)
656 {
657 if (val)
658 set_bit(TTY_PORT_INITIALIZED, &port->iflags);
659 else
660 clear_bit(TTY_PORT_INITIALIZED, &port->iflags);
661 }
662
tty_port_kopened(struct tty_port * port)663 static inline bool tty_port_kopened(struct tty_port *port)
664 {
665 return test_bit(TTY_PORT_KOPENED, &port->iflags);
666 }
667
tty_port_set_kopened(struct tty_port * port,bool val)668 static inline void tty_port_set_kopened(struct tty_port *port, bool val)
669 {
670 if (val)
671 set_bit(TTY_PORT_KOPENED, &port->iflags);
672 else
673 clear_bit(TTY_PORT_KOPENED, &port->iflags);
674 }
675
676 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
677 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
678 extern int tty_port_carrier_raised(struct tty_port *port);
679 extern void tty_port_raise_dtr_rts(struct tty_port *port);
680 extern void tty_port_lower_dtr_rts(struct tty_port *port);
681 extern void tty_port_hangup(struct tty_port *port);
682 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
683 extern void tty_port_tty_wakeup(struct tty_port *port);
684 extern int tty_port_block_til_ready(struct tty_port *port,
685 struct tty_struct *tty, struct file *filp);
686 extern int tty_port_close_start(struct tty_port *port,
687 struct tty_struct *tty, struct file *filp);
688 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
689 extern void tty_port_close(struct tty_port *port,
690 struct tty_struct *tty, struct file *filp);
691 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
692 struct tty_struct *tty);
693 extern int tty_port_open(struct tty_port *port,
694 struct tty_struct *tty, struct file *filp);
tty_port_users(struct tty_port * port)695 static inline int tty_port_users(struct tty_port *port)
696 {
697 return port->count + port->blocked_open;
698 }
699
700 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
701 extern int tty_unregister_ldisc(int disc);
702 extern int tty_set_ldisc(struct tty_struct *tty, int disc);
703 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
704 extern void tty_ldisc_release(struct tty_struct *tty);
705 extern int __must_check tty_ldisc_init(struct tty_struct *tty);
706 extern void tty_ldisc_deinit(struct tty_struct *tty);
707 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
708 char *f, int count);
709
710 /* n_tty.c */
711 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
712 #ifdef CONFIG_TTY
713 extern void __init n_tty_init(void);
714 #else
n_tty_init(void)715 static inline void n_tty_init(void) { }
716 #endif
717
718 /* tty_audit.c */
719 #ifdef CONFIG_AUDIT
720 extern void tty_audit_add_data(struct tty_struct *tty, const void *data,
721 size_t size);
722 extern void tty_audit_exit(void);
723 extern void tty_audit_fork(struct signal_struct *sig);
724 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
725 extern int tty_audit_push(void);
726 #else
tty_audit_add_data(struct tty_struct * tty,const void * data,size_t size)727 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data,
728 size_t size)
729 {
730 }
tty_audit_tiocsti(struct tty_struct * tty,char ch)731 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
732 {
733 }
tty_audit_exit(void)734 static inline void tty_audit_exit(void)
735 {
736 }
tty_audit_fork(struct signal_struct * sig)737 static inline void tty_audit_fork(struct signal_struct *sig)
738 {
739 }
tty_audit_push(void)740 static inline int tty_audit_push(void)
741 {
742 return 0;
743 }
744 #endif
745
746 /* tty_ioctl.c */
747 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
748 unsigned int cmd, unsigned long arg);
749 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
750 unsigned int cmd, unsigned long arg);
751
752 /* vt.c */
753
754 extern int vt_ioctl(struct tty_struct *tty,
755 unsigned int cmd, unsigned long arg);
756
757 extern long vt_compat_ioctl(struct tty_struct *tty,
758 unsigned int cmd, unsigned long arg);
759
760 /* tty_mutex.c */
761 /* functions for preparation of BKL removal */
762 extern void tty_lock(struct tty_struct *tty);
763 extern int tty_lock_interruptible(struct tty_struct *tty);
764 extern void tty_unlock(struct tty_struct *tty);
765 extern void tty_lock_slave(struct tty_struct *tty);
766 extern void tty_unlock_slave(struct tty_struct *tty);
767 extern void tty_set_lock_subclass(struct tty_struct *tty);
768
769 #ifdef CONFIG_PROC_FS
770 extern void proc_tty_register_driver(struct tty_driver *);
771 extern void proc_tty_unregister_driver(struct tty_driver *);
772 #else
proc_tty_register_driver(struct tty_driver * d)773 static inline void proc_tty_register_driver(struct tty_driver *d) {}
proc_tty_unregister_driver(struct tty_driver * d)774 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
775 #endif
776
777 #define tty_msg(fn, tty, f, ...) \
778 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__)
779
780 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__)
781 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__)
782 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__)
783 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__)
784 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__)
785
786 #define tty_info_ratelimited(tty, f, ...) \
787 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__)
788
789 #endif
790
