Line data Source code
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_buffer.h>
10 : #include <linux/tty_driver.h>
11 : #include <linux/tty_ldisc.h>
12 : #include <linux/tty_port.h>
13 : #include <linux/mutex.h>
14 : #include <linux/tty_flags.h>
15 : #include <uapi/linux/tty.h>
16 : #include <linux/rwsem.h>
17 : #include <linux/llist.h>
18 :
19 :
20 : /*
21 : * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
22 : * hardcoded at present.)
23 : */
24 : #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
25 : #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
26 : #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
27 :
28 : /*
29 : * This character is the same as _POSIX_VDISABLE: it cannot be used as
30 : * a c_cc[] character, but indicates that a particular special character
31 : * isn't in use (eg VINTR has no character etc)
32 : */
33 : #define __DISABLED_CHAR '\0'
34 :
35 : #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
36 : #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
37 : #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
38 : #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
39 : #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
40 : #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
41 : #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
42 : #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
43 : #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
44 : #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
45 : #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
46 : #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
47 : #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
48 : #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
49 : #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
50 : #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
51 : #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
52 :
53 : #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
54 : #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
55 : #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
56 : #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
57 :
58 : #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
59 : #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
60 : #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
61 : #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
62 : #define I_INPCK(tty) _I_FLAG((tty), INPCK)
63 : #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
64 : #define I_INLCR(tty) _I_FLAG((tty), INLCR)
65 : #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
66 : #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
67 : #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
68 : #define I_IXON(tty) _I_FLAG((tty), IXON)
69 : #define I_IXANY(tty) _I_FLAG((tty), IXANY)
70 : #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
71 : #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
72 : #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
73 :
74 : #define O_OPOST(tty) _O_FLAG((tty), OPOST)
75 : #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
76 : #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
77 : #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
78 : #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
79 : #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
80 : #define O_OFILL(tty) _O_FLAG((tty), OFILL)
81 : #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
82 : #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
83 : #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
84 : #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
85 : #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
86 : #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
87 : #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
88 :
89 : #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
90 : #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
91 : #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
92 : #define C_CREAD(tty) _C_FLAG((tty), CREAD)
93 : #define C_PARENB(tty) _C_FLAG((tty), PARENB)
94 : #define C_PARODD(tty) _C_FLAG((tty), PARODD)
95 : #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
96 : #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
97 : #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
98 : #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
99 : #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR)
100 :
101 : #define L_ISIG(tty) _L_FLAG((tty), ISIG)
102 : #define L_ICANON(tty) _L_FLAG((tty), ICANON)
103 : #define L_XCASE(tty) _L_FLAG((tty), XCASE)
104 : #define L_ECHO(tty) _L_FLAG((tty), ECHO)
105 : #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
106 : #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
107 : #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
108 : #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
109 : #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
110 : #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
111 : #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
112 : #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
113 : #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
114 : #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
115 : #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
116 : #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
117 :
118 : struct device;
119 : struct signal_struct;
120 : struct tty_operations;
121 :
122 : /**
123 : * struct tty_struct - state associated with a tty while open
124 : *
125 : * @kref: reference counting by tty_kref_get() and tty_kref_put(), reaching zero
126 : * frees the structure
127 : * @dev: class device or %NULL (e.g. ptys, serdev)
128 : * @driver: &struct tty_driver operating this tty
129 : * @ops: &struct tty_operations of @driver for this tty (open, close, etc.)
130 : * @index: index of this tty (e.g. to construct @name like tty12)
131 : * @ldisc_sem: protects line discipline changes (@ldisc) -- lock tty not pty
132 : * @ldisc: the current line discipline for this tty (n_tty by default)
133 : * @atomic_write_lock: protects against concurrent writers, i.e. locks
134 : * @write_cnt, @write_buf and similar
135 : * @legacy_mutex: leftover from history (BKL -> BTM -> @legacy_mutex),
136 : * protecting several operations on this tty
137 : * @throttle_mutex: protects against concurrent tty_throttle_safe() and
138 : * tty_unthrottle_safe() (but not tty_unthrottle())
139 : * @termios_rwsem: protects @termios and @termios_locked
140 : * @winsize_mutex: protects @winsize
141 : * @termios: termios for the current tty, copied from/to @driver.termios
142 : * @termios_locked: locked termios (by %TIOCGLCKTRMIOS and %TIOCSLCKTRMIOS
143 : * ioctls)
144 : * @name: name of the tty constructed by tty_line_name() (e.g. ttyS3)
145 : * @flags: bitwise OR of %TTY_THROTTLED, %TTY_IO_ERROR, ...
146 : * @count: count of open processes, reaching zero cancels all the work for
147 : * this tty and drops a @kref too (but does not free this tty)
148 : * @winsize: size of the terminal "window" (cf. @winsize_mutex)
149 : * @flow: flow settings grouped together, see also @flow.unused
150 : * @flow.lock: lock for @flow members
151 : * @flow.stopped: tty stopped/started by stop_tty()/start_tty()
152 : * @flow.tco_stopped: tty stopped/started by %TCOOFF/%TCOON ioctls (it has
153 : * precedence over @flow.stopped)
154 : * @flow.unused: alignment for Alpha, so that no members other than @flow.* are
155 : * modified by the same 64b word store. The @flow's __aligned is
156 : * there for the very same reason.
157 : * @ctrl: control settings grouped together, see also @ctrl.unused
158 : * @ctrl.lock: lock for @ctrl members
159 : * @ctrl.pgrp: process group of this tty (setpgrp(2))
160 : * @ctrl.session: session of this tty (setsid(2)). Writes are protected by both
161 : * @ctrl.lock and @legacy_mutex, readers must use at least one of
162 : * them.
163 : * @ctrl.pktstatus: packet mode status (bitwise OR of %TIOCPKT_ constants)
164 : * @ctrl.packet: packet mode enabled
165 : * @ctrl.unused: alignment for Alpha, see @flow.unused for explanation
166 : * @hw_stopped: not controlled by the tty layer, under @driver's control for CTS
167 : * handling
168 : * @receive_room: bytes permitted to feed to @ldisc without any being lost
169 : * @flow_change: controls behavior of throttling, see tty_throttle_safe() and
170 : * tty_unthrottle_safe()
171 : * @link: link to another pty (master -> slave and vice versa)
172 : * @fasync: state for %O_ASYNC (for %SIGIO); managed by fasync_helper()
173 : * @write_wait: concurrent writers are waiting in this queue until they are
174 : * allowed to write
175 : * @read_wait: readers wait for data in this queue
176 : * @hangup_work: normally a work to perform a hangup (do_tty_hangup()); while
177 : * freeing the tty, (re)used to release_one_tty()
178 : * @disc_data: pointer to @ldisc's private data (e.g. to &struct n_tty_data)
179 : * @driver_data: pointer to @driver's private data (e.g. &struct uart_state)
180 : * @files_lock: protects @tty_files list
181 : * @tty_files: list of (re)openers of this tty (i.e. linked &struct
182 : * tty_file_private)
183 : * @closing: when set during close, n_tty processes only START & STOP chars
184 : * @write_buf: temporary buffer used during tty_write() to copy user data to
185 : * @write_cnt: count of bytes written in tty_write() to @write_buf
186 : * @SAK_work: if the tty has a pending do_SAK, it is queued here
187 : * @port: persistent storage for this device (i.e. &struct tty_port)
188 : *
189 : * All of the state associated with a tty while the tty is open. Persistent
190 : * storage for tty devices is referenced here as @port and is documented in
191 : * &struct tty_port.
192 : */
193 : struct tty_struct {
194 : struct kref kref;
195 : struct device *dev;
196 : struct tty_driver *driver;
197 : const struct tty_operations *ops;
198 : int index;
199 :
200 : struct ld_semaphore ldisc_sem;
201 : struct tty_ldisc *ldisc;
202 :
203 : struct mutex atomic_write_lock;
204 : struct mutex legacy_mutex;
205 : struct mutex throttle_mutex;
206 : struct rw_semaphore termios_rwsem;
207 : struct mutex winsize_mutex;
208 : struct ktermios termios, termios_locked;
209 : char name[64];
210 : unsigned long flags;
211 : int count;
212 : struct winsize winsize;
213 :
214 : struct {
215 : spinlock_t lock;
216 : bool stopped;
217 : bool tco_stopped;
218 : unsigned long unused[0];
219 : } __aligned(sizeof(unsigned long)) flow;
220 :
221 : struct {
222 : spinlock_t lock;
223 : struct pid *pgrp;
224 : struct pid *session;
225 : unsigned char pktstatus;
226 : bool packet;
227 : unsigned long unused[0];
228 : } __aligned(sizeof(unsigned long)) ctrl;
229 :
230 : bool hw_stopped;
231 : unsigned int receive_room;
232 : int flow_change;
233 :
234 : struct tty_struct *link;
235 : struct fasync_struct *fasync;
236 : wait_queue_head_t write_wait;
237 : wait_queue_head_t read_wait;
238 : struct work_struct hangup_work;
239 : void *disc_data;
240 : void *driver_data;
241 : spinlock_t files_lock;
242 : struct list_head tty_files;
243 :
244 : #define N_TTY_BUF_SIZE 4096
245 :
246 : int closing;
247 : unsigned char *write_buf;
248 : int write_cnt;
249 : struct work_struct SAK_work;
250 : struct tty_port *port;
251 : } __randomize_layout;
252 :
253 : /* Each of a tty's open files has private_data pointing to tty_file_private */
254 : struct tty_file_private {
255 : struct tty_struct *tty;
256 : struct file *file;
257 : struct list_head list;
258 : };
259 :
260 : /**
261 : * DOC: TTY Struct Flags
262 : *
263 : * These bits are used in the :c:member:`tty_struct.flags` field.
264 : *
265 : * So that interrupts won't be able to mess up the queues,
266 : * copy_to_cooked must be atomic with respect to itself, as must
267 : * tty->write. Thus, you must use the inline functions set_bit() and
268 : * clear_bit() to make things atomic.
269 : *
270 : * TTY_THROTTLED
271 : * Driver input is throttled. The ldisc should call
272 : * :c:member:`tty_driver.unthrottle()` in order to resume reception when
273 : * it is ready to process more data (at threshold min).
274 : *
275 : * TTY_IO_ERROR
276 : * If set, causes all subsequent userspace read/write calls on the tty to
277 : * fail, returning -%EIO. (May be no ldisc too.)
278 : *
279 : * TTY_OTHER_CLOSED
280 : * Device is a pty and the other side has closed.
281 : *
282 : * TTY_EXCLUSIVE
283 : * Exclusive open mode (a single opener).
284 : *
285 : * TTY_DO_WRITE_WAKEUP
286 : * If set, causes the driver to call the
287 : * :c:member:`tty_ldisc_ops.write_wakeup()` method in order to resume
288 : * transmission when it can accept more data to transmit.
289 : *
290 : * TTY_LDISC_OPEN
291 : * Indicates that a line discipline is open. For debugging purposes only.
292 : *
293 : * TTY_PTY_LOCK
294 : * A flag private to pty code to implement %TIOCSPTLCK/%TIOCGPTLCK logic.
295 : *
296 : * TTY_NO_WRITE_SPLIT
297 : * Prevent driver from splitting up writes into smaller chunks (preserve
298 : * write boundaries to driver).
299 : *
300 : * TTY_HUPPED
301 : * The TTY was hung up. This is set post :c:member:`tty_driver.hangup()`.
302 : *
303 : * TTY_HUPPING
304 : * The TTY is in the process of hanging up to abort potential readers.
305 : *
306 : * TTY_LDISC_CHANGING
307 : * Line discipline for this TTY is being changed. I/O should not block
308 : * when this is set. Use tty_io_nonblock() to check.
309 : *
310 : * TTY_LDISC_HALTED
311 : * Line discipline for this TTY was stopped. No work should be queued to
312 : * this ldisc.
313 : */
314 : #define TTY_THROTTLED 0
315 : #define TTY_IO_ERROR 1
316 : #define TTY_OTHER_CLOSED 2
317 : #define TTY_EXCLUSIVE 3
318 : #define TTY_DO_WRITE_WAKEUP 5
319 : #define TTY_LDISC_OPEN 11
320 : #define TTY_PTY_LOCK 16
321 : #define TTY_NO_WRITE_SPLIT 17
322 : #define TTY_HUPPED 18
323 : #define TTY_HUPPING 19
324 : #define TTY_LDISC_CHANGING 20
325 : #define TTY_LDISC_HALTED 22
326 :
327 : static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file)
328 : {
329 0 : return file->f_flags & O_NONBLOCK ||
330 0 : test_bit(TTY_LDISC_CHANGING, &tty->flags);
331 : }
332 :
333 : static inline bool tty_io_error(struct tty_struct *tty)
334 : {
335 0 : return test_bit(TTY_IO_ERROR, &tty->flags);
336 : }
337 :
338 : static inline bool tty_throttled(struct tty_struct *tty)
339 : {
340 0 : return test_bit(TTY_THROTTLED, &tty->flags);
341 : }
342 :
343 : #ifdef CONFIG_TTY
344 : void tty_kref_put(struct tty_struct *tty);
345 : struct pid *tty_get_pgrp(struct tty_struct *tty);
346 : void tty_vhangup_self(void);
347 : void disassociate_ctty(int priv);
348 : dev_t tty_devnum(struct tty_struct *tty);
349 : void proc_clear_tty(struct task_struct *p);
350 : struct tty_struct *get_current_tty(void);
351 : /* tty_io.c */
352 : int __init tty_init(void);
353 : const char *tty_name(const struct tty_struct *tty);
354 : struct tty_struct *tty_kopen_exclusive(dev_t device);
355 : struct tty_struct *tty_kopen_shared(dev_t device);
356 : void tty_kclose(struct tty_struct *tty);
357 : int tty_dev_name_to_number(const char *name, dev_t *number);
358 : #else
359 : static inline void tty_kref_put(struct tty_struct *tty)
360 : { }
361 : static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
362 : { return NULL; }
363 : static inline void tty_vhangup_self(void)
364 : { }
365 : static inline void disassociate_ctty(int priv)
366 : { }
367 : static inline dev_t tty_devnum(struct tty_struct *tty)
368 : { return 0; }
369 : static inline void proc_clear_tty(struct task_struct *p)
370 : { }
371 : static inline struct tty_struct *get_current_tty(void)
372 : { return NULL; }
373 : /* tty_io.c */
374 : static inline int __init tty_init(void)
375 : { return 0; }
376 : static inline const char *tty_name(const struct tty_struct *tty)
377 : { return "(none)"; }
378 : static inline struct tty_struct *tty_kopen_exclusive(dev_t device)
379 : { return ERR_PTR(-ENODEV); }
380 : static inline void tty_kclose(struct tty_struct *tty)
381 : { }
382 : static inline int tty_dev_name_to_number(const char *name, dev_t *number)
383 : { return -ENOTSUPP; }
384 : #endif
385 :
386 : extern struct ktermios tty_std_termios;
387 :
388 : int vcs_init(void);
389 :
390 : extern const struct class tty_class;
391 :
392 : /**
393 : * tty_kref_get - get a tty reference
394 : * @tty: tty device
395 : *
396 : * Return a new reference to a tty object. The caller must hold
397 : * sufficient locks/counts to ensure that their existing reference cannot
398 : * go away
399 : */
400 :
401 : static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
402 : {
403 382 : if (tty)
404 0 : kref_get(&tty->kref);
405 : return tty;
406 : }
407 :
408 : const char *tty_driver_name(const struct tty_struct *tty);
409 : void tty_wait_until_sent(struct tty_struct *tty, long timeout);
410 : void stop_tty(struct tty_struct *tty);
411 : void start_tty(struct tty_struct *tty);
412 : void tty_write_message(struct tty_struct *tty, char *msg);
413 : int tty_send_xchar(struct tty_struct *tty, char ch);
414 : int tty_put_char(struct tty_struct *tty, unsigned char c);
415 : unsigned int tty_chars_in_buffer(struct tty_struct *tty);
416 : unsigned int tty_write_room(struct tty_struct *tty);
417 : void tty_driver_flush_buffer(struct tty_struct *tty);
418 : void tty_unthrottle(struct tty_struct *tty);
419 : int tty_throttle_safe(struct tty_struct *tty);
420 : int tty_unthrottle_safe(struct tty_struct *tty);
421 : int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
422 : int tty_get_icount(struct tty_struct *tty,
423 : struct serial_icounter_struct *icount);
424 : int is_current_pgrp_orphaned(void);
425 : void tty_hangup(struct tty_struct *tty);
426 : void tty_vhangup(struct tty_struct *tty);
427 : int tty_hung_up_p(struct file *filp);
428 : void do_SAK(struct tty_struct *tty);
429 : void __do_SAK(struct tty_struct *tty);
430 : void no_tty(void);
431 : speed_t tty_termios_baud_rate(const struct ktermios *termios);
432 : void tty_termios_encode_baud_rate(struct ktermios *termios, speed_t ibaud,
433 : speed_t obaud);
434 : void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud,
435 : speed_t obaud);
436 :
437 : /**
438 : * tty_get_baud_rate - get tty bit rates
439 : * @tty: tty to query
440 : *
441 : * Returns the baud rate as an integer for this terminal. The
442 : * termios lock must be held by the caller and the terminal bit
443 : * flags may be updated.
444 : *
445 : * Locking: none
446 : */
447 : static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
448 : {
449 0 : return tty_termios_baud_rate(&tty->termios);
450 : }
451 :
452 : unsigned char tty_get_char_size(unsigned int cflag);
453 : unsigned char tty_get_frame_size(unsigned int cflag);
454 :
455 : void tty_termios_copy_hw(struct ktermios *new, const struct ktermios *old);
456 : bool tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b);
457 : int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
458 :
459 : void tty_wakeup(struct tty_struct *tty);
460 :
461 : int tty_mode_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
462 : int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
463 : struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
464 : void tty_release_struct(struct tty_struct *tty, int idx);
465 : void tty_init_termios(struct tty_struct *tty);
466 : void tty_save_termios(struct tty_struct *tty);
467 : int tty_standard_install(struct tty_driver *driver,
468 : struct tty_struct *tty);
469 :
470 : extern struct mutex tty_mutex;
471 :
472 : /* n_tty.c */
473 : void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
474 : #ifdef CONFIG_TTY
475 : void __init n_tty_init(void);
476 : #else
477 : static inline void n_tty_init(void) { }
478 : #endif
479 :
480 : /* tty_audit.c */
481 : #ifdef CONFIG_AUDIT
482 : void tty_audit_exit(void);
483 : void tty_audit_fork(struct signal_struct *sig);
484 : int tty_audit_push(void);
485 : #else
486 : static inline void tty_audit_exit(void)
487 : {
488 : }
489 : static inline void tty_audit_fork(struct signal_struct *sig)
490 : {
491 : }
492 : static inline int tty_audit_push(void)
493 : {
494 : return 0;
495 : }
496 : #endif
497 :
498 : /* tty_ioctl.c */
499 : int n_tty_ioctl_helper(struct tty_struct *tty, unsigned int cmd,
500 : unsigned long arg);
501 :
502 : /* vt.c */
503 :
504 : int vt_ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
505 :
506 : long vt_compat_ioctl(struct tty_struct *tty, unsigned int cmd,
507 : unsigned long arg);
508 :
509 : /* tty_mutex.c */
510 : /* functions for preparation of BKL removal */
511 : void tty_lock(struct tty_struct *tty);
512 : int tty_lock_interruptible(struct tty_struct *tty);
513 : void tty_unlock(struct tty_struct *tty);
514 : void tty_lock_slave(struct tty_struct *tty);
515 : void tty_unlock_slave(struct tty_struct *tty);
516 : void tty_set_lock_subclass(struct tty_struct *tty);
517 :
518 : #endif
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