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