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