1 #ifndef _LINUX_TTY_H
2 #define _LINUX_TTY_H
3
4 #include <linux/fs.h>
5 #include <linux/major.h>
6 #include <linux/termios.h>
7 #include <linux/workqueue.h>
8 #include <linux/tty_driver.h>
9 #include <linux/tty_ldisc.h>
10 #include <linux/mutex.h>
11 #include <linux/tty_flags.h>
12 #include <uapi/linux/tty.h>
13 #include <linux/rwsem.h>
14 #include <linux/llist.h>
15
16
17 /*
18 * Lock subclasses for tty locks
19 *
20 * TTY_LOCK_NORMAL is for normal ttys and master ptys.
21 * TTY_LOCK_SLAVE is for slave ptys only.
22 *
23 * Lock subclasses are necessary for handling nested locking with pty pairs.
24 * tty locks which use nested locking:
25 *
26 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
27 * The stable lock order is master pty first, then slave pty.
28 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
29 * Subclassing this lock enables the slave pty to hold its
30 * termios_rwsem when claiming the master tty_buffer lock.
31 * tty_buffer lock - slave ptys can claim nested buffer lock when handling
32 * signal chars. The stable lock order is slave pty, then
33 * master.
34 */
35
36 enum {
37 TTY_LOCK_NORMAL = 0,
38 TTY_LOCK_SLAVE,
39 };
40
41 /*
42 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
43 * hardcoded at present.)
44 */
45 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
46 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
47 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
48
49 /*
50 * This character is the same as _POSIX_VDISABLE: it cannot be used as
51 * a c_cc[] character, but indicates that a particular special character
52 * isn't in use (eg VINTR has no character etc)
53 */
54 #define __DISABLED_CHAR '\0'
55
56 struct tty_buffer {
57 union {
58 struct tty_buffer *next;
59 struct llist_node free;
60 };
61 int used;
62 int size;
63 int commit;
64 int read;
65 int flags;
66 /* Data points here */
67 unsigned long data[0];
68 };
69
70 /* Values for .flags field of tty_buffer */
71 #define TTYB_NORMAL 1 /* buffer has no flags buffer */
72
char_buf_ptr(struct tty_buffer * b,int ofs)73 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs)
74 {
75 return ((unsigned char *)b->data) + ofs;
76 }
77
flag_buf_ptr(struct tty_buffer * b,int ofs)78 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs)
79 {
80 return (char *)char_buf_ptr(b, ofs) + b->size;
81 }
82
83 struct tty_bufhead {
84 struct tty_buffer *head; /* Queue head */
85 struct work_struct work;
86 struct mutex lock;
87 atomic_t priority;
88 struct tty_buffer sentinel;
89 struct llist_head free; /* Free queue head */
90 atomic_t mem_used; /* In-use buffers excluding free list */
91 int mem_limit;
92 struct tty_buffer *tail; /* Active buffer */
93 };
94 /*
95 * When a break, frame error, or parity error happens, these codes are
96 * stuffed into the flags buffer.
97 */
98 #define TTY_NORMAL 0
99 #define TTY_BREAK 1
100 #define TTY_FRAME 2
101 #define TTY_PARITY 3
102 #define TTY_OVERRUN 4
103
104 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
105 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
106 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
107 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
108 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
109 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
110 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
111 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
112 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
113 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
114 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
115 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
116 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
117 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
118 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
119 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
120 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
121
122 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
123 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
124 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
125 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
126
127 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
128 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
129 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
130 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
131 #define I_INPCK(tty) _I_FLAG((tty), INPCK)
132 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
133 #define I_INLCR(tty) _I_FLAG((tty), INLCR)
134 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
135 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
136 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
137 #define I_IXON(tty) _I_FLAG((tty), IXON)
138 #define I_IXANY(tty) _I_FLAG((tty), IXANY)
139 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
140 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
141 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
142
143 #define O_OPOST(tty) _O_FLAG((tty), OPOST)
144 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
145 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
146 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
147 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
148 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
149 #define O_OFILL(tty) _O_FLAG((tty), OFILL)
150 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
151 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
152 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
153 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
154 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
155 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
156 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
157
158 #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
159 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
160 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
161 #define C_CREAD(tty) _C_FLAG((tty), CREAD)
162 #define C_PARENB(tty) _C_FLAG((tty), PARENB)
163 #define C_PARODD(tty) _C_FLAG((tty), PARODD)
164 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
165 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
166 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
167 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
168 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR)
169
170 #define L_ISIG(tty) _L_FLAG((tty), ISIG)
171 #define L_ICANON(tty) _L_FLAG((tty), ICANON)
172 #define L_XCASE(tty) _L_FLAG((tty), XCASE)
173 #define L_ECHO(tty) _L_FLAG((tty), ECHO)
174 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
175 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
176 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
177 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
178 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
179 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
180 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
181 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
182 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
183 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
184 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
185 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
186
187 struct device;
188 struct signal_struct;
189
190 /*
191 * Port level information. Each device keeps its own port level information
192 * so provide a common structure for those ports wanting to use common support
193 * routines.
194 *
195 * The tty port has a different lifetime to the tty so must be kept apart.
196 * In addition be careful as tty -> port mappings are valid for the life
197 * of the tty object but in many cases port -> tty mappings are valid only
198 * until a hangup so don't use the wrong path.
199 */
200
201 struct tty_port;
202
203 struct tty_port_operations {
204 /* Return 1 if the carrier is raised */
205 int (*carrier_raised)(struct tty_port *port);
206 /* Control the DTR line */
207 void (*dtr_rts)(struct tty_port *port, int raise);
208 /* Called when the last close completes or a hangup finishes
209 IFF the port was initialized. Do not use to free resources. Called
210 under the port mutex to serialize against activate/shutdowns */
211 void (*shutdown)(struct tty_port *port);
212 /* Called under the port mutex from tty_port_open, serialized using
213 the port mutex */
214 /* FIXME: long term getting the tty argument *out* of this would be
215 good for consoles */
216 int (*activate)(struct tty_port *port, struct tty_struct *tty);
217 /* Called on the final put of a port */
218 void (*destruct)(struct tty_port *port);
219 };
220
221 struct tty_port {
222 struct tty_bufhead buf; /* Locked internally */
223 struct tty_struct *tty; /* Back pointer */
224 struct tty_struct *itty; /* internal back ptr */
225 const struct tty_port_operations *ops; /* Port operations */
226 spinlock_t lock; /* Lock protecting tty field */
227 int blocked_open; /* Waiting to open */
228 int count; /* Usage count */
229 wait_queue_head_t open_wait; /* Open waiters */
230 wait_queue_head_t delta_msr_wait; /* Modem status change */
231 unsigned long flags; /* TTY flags ASY_*/
232 unsigned char console:1, /* port is a console */
233 low_latency:1; /* optional: tune for latency */
234 struct mutex mutex; /* Locking */
235 struct mutex buf_mutex; /* Buffer alloc lock */
236 unsigned char *xmit_buf; /* Optional buffer */
237 unsigned int close_delay; /* Close port delay */
238 unsigned int closing_wait; /* Delay for output */
239 int drain_delay; /* Set to zero if no pure time
240 based drain is needed else
241 set to size of fifo */
242 struct kref kref; /* Ref counter */
243 };
244
245 /*
246 * Where all of the state associated with a tty is kept while the tty
247 * is open. Since the termios state should be kept even if the tty
248 * has been closed --- for things like the baud rate, etc --- it is
249 * not stored here, but rather a pointer to the real state is stored
250 * here. Possible the winsize structure should have the same
251 * treatment, but (1) the default 80x24 is usually right and (2) it's
252 * most often used by a windowing system, which will set the correct
253 * size each time the window is created or resized anyway.
254 * - TYT, 9/14/92
255 */
256
257 struct tty_operations;
258
259 struct tty_struct {
260 int magic;
261 struct kref kref;
262 struct device *dev;
263 struct tty_driver *driver;
264 const struct tty_operations *ops;
265 int index;
266
267 /* Protects ldisc changes: Lock tty not pty */
268 struct ld_semaphore ldisc_sem;
269 struct tty_ldisc *ldisc;
270
271 struct mutex atomic_write_lock;
272 struct mutex legacy_mutex;
273 struct mutex throttle_mutex;
274 struct rw_semaphore termios_rwsem;
275 struct mutex winsize_mutex;
276 spinlock_t ctrl_lock;
277 spinlock_t flow_lock;
278 /* Termios values are protected by the termios rwsem */
279 struct ktermios termios, termios_locked;
280 struct termiox *termiox; /* May be NULL for unsupported */
281 char name[64];
282 struct pid *pgrp; /* Protected by ctrl lock */
283 struct pid *session;
284 unsigned long flags;
285 int count;
286 struct winsize winsize; /* winsize_mutex */
287 unsigned long stopped:1, /* flow_lock */
288 flow_stopped:1,
289 unused:BITS_PER_LONG - 2;
290 int hw_stopped;
291 unsigned long ctrl_status:8, /* ctrl_lock */
292 packet:1,
293 unused_ctrl:BITS_PER_LONG - 9;
294 unsigned int receive_room; /* Bytes free for queue */
295 int flow_change;
296
297 struct tty_struct *link;
298 struct fasync_struct *fasync;
299 int alt_speed; /* For magic substitution of 38400 bps */
300 wait_queue_head_t write_wait;
301 wait_queue_head_t read_wait;
302 struct work_struct hangup_work;
303 void *disc_data;
304 void *driver_data;
305 struct list_head tty_files;
306
307 #define N_TTY_BUF_SIZE 4096
308
309 int closing;
310 unsigned char *write_buf;
311 int write_cnt;
312 /* If the tty has a pending do_SAK, queue it here - akpm */
313 struct work_struct SAK_work;
314 struct tty_port *port;
315 };
316
317 /* Each of a tty's open files has private_data pointing to tty_file_private */
318 struct tty_file_private {
319 struct tty_struct *tty;
320 struct file *file;
321 struct list_head list;
322 };
323
324 /* tty magic number */
325 #define TTY_MAGIC 0x5401
326
327 /*
328 * These bits are used in the flags field of the tty structure.
329 *
330 * So that interrupts won't be able to mess up the queues,
331 * copy_to_cooked must be atomic with respect to itself, as must
332 * tty->write. Thus, you must use the inline functions set_bit() and
333 * clear_bit() to make things atomic.
334 */
335 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
336 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
337 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
338 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
339 #define TTY_DEBUG 4 /* Debugging */
340 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
341 #define TTY_LDISC_OPEN 11 /* Line discipline is open */
342 #define TTY_PTY_LOCK 16 /* pty private */
343 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
344 #define TTY_HUPPED 18 /* Post driver->hangup() */
345 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */
346
347 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
348
349 /* Values for tty->flow_change */
350 #define TTY_THROTTLE_SAFE 1
351 #define TTY_UNTHROTTLE_SAFE 2
352
__tty_set_flow_change(struct tty_struct * tty,int val)353 static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
354 {
355 tty->flow_change = val;
356 }
357
tty_set_flow_change(struct tty_struct * tty,int val)358 static inline void tty_set_flow_change(struct tty_struct *tty, int val)
359 {
360 tty->flow_change = val;
361 smp_mb();
362 }
363
364 #ifdef CONFIG_TTY
365 extern void console_init(void);
366 extern void tty_kref_put(struct tty_struct *tty);
367 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
368 extern void tty_vhangup_self(void);
369 extern void disassociate_ctty(int priv);
370 extern dev_t tty_devnum(struct tty_struct *tty);
371 extern void proc_clear_tty(struct task_struct *p);
372 extern struct tty_struct *get_current_tty(void);
373 /* tty_io.c */
374 extern int __init tty_init(void);
375 #else
console_init(void)376 static inline void console_init(void)
377 { }
tty_kref_put(struct tty_struct * tty)378 static inline void tty_kref_put(struct tty_struct *tty)
379 { }
tty_get_pgrp(struct tty_struct * tty)380 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
381 { return NULL; }
tty_vhangup_self(void)382 static inline void tty_vhangup_self(void)
383 { }
disassociate_ctty(int priv)384 static inline void disassociate_ctty(int priv)
385 { }
tty_devnum(struct tty_struct * tty)386 static inline dev_t tty_devnum(struct tty_struct *tty)
387 { return 0; }
proc_clear_tty(struct task_struct * p)388 static inline void proc_clear_tty(struct task_struct *p)
389 { }
get_current_tty(void)390 static inline struct tty_struct *get_current_tty(void)
391 { return NULL; }
392 /* tty_io.c */
tty_init(void)393 static inline int __init tty_init(void)
394 { return 0; }
395 #endif
396
397 extern void tty_write_flush(struct tty_struct *);
398
399 extern struct ktermios tty_std_termios;
400
401 extern int vcs_init(void);
402
403 extern struct class *tty_class;
404
405 /**
406 * tty_kref_get - get a tty reference
407 * @tty: tty device
408 *
409 * Return a new reference to a tty object. The caller must hold
410 * sufficient locks/counts to ensure that their existing reference cannot
411 * go away
412 */
413
tty_kref_get(struct tty_struct * tty)414 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
415 {
416 if (tty)
417 kref_get(&tty->kref);
418 return tty;
419 }
420
421 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
422 const char *routine);
423 extern const char *tty_name(const struct tty_struct *tty);
424 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
425 extern int __tty_check_change(struct tty_struct *tty, int sig);
426 extern int tty_check_change(struct tty_struct *tty);
427 extern void __stop_tty(struct tty_struct *tty);
428 extern void stop_tty(struct tty_struct *tty);
429 extern void __start_tty(struct tty_struct *tty);
430 extern void start_tty(struct tty_struct *tty);
431 extern int tty_register_driver(struct tty_driver *driver);
432 extern int tty_unregister_driver(struct tty_driver *driver);
433 extern struct device *tty_register_device(struct tty_driver *driver,
434 unsigned index, struct device *dev);
435 extern struct device *tty_register_device_attr(struct tty_driver *driver,
436 unsigned index, struct device *device,
437 void *drvdata,
438 const struct attribute_group **attr_grp);
439 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
440 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
441 int buflen);
442 extern void tty_write_message(struct tty_struct *tty, char *msg);
443 extern int tty_send_xchar(struct tty_struct *tty, char ch);
444 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
445 extern int tty_chars_in_buffer(struct tty_struct *tty);
446 extern int tty_write_room(struct tty_struct *tty);
447 extern void tty_driver_flush_buffer(struct tty_struct *tty);
448 extern void tty_throttle(struct tty_struct *tty);
449 extern void tty_unthrottle(struct tty_struct *tty);
450 extern int tty_throttle_safe(struct tty_struct *tty);
451 extern int tty_unthrottle_safe(struct tty_struct *tty);
452 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
453 extern void tty_driver_remove_tty(struct tty_driver *driver,
454 struct tty_struct *tty);
455 extern void tty_free_termios(struct tty_struct *tty);
456 extern int is_current_pgrp_orphaned(void);
457 extern int is_ignored(int sig);
458 extern int tty_signal(int sig, struct tty_struct *tty);
459 extern void tty_hangup(struct tty_struct *tty);
460 extern void tty_vhangup(struct tty_struct *tty);
461 extern int tty_hung_up_p(struct file *filp);
462 extern void do_SAK(struct tty_struct *tty);
463 extern void __do_SAK(struct tty_struct *tty);
464 extern void no_tty(void);
465 extern void tty_buffer_free_all(struct tty_port *port);
466 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld);
467 extern void tty_buffer_init(struct tty_port *port);
468 extern void tty_buffer_set_lock_subclass(struct tty_port *port);
469 extern bool tty_buffer_restart_work(struct tty_port *port);
470 extern bool tty_buffer_cancel_work(struct tty_port *port);
471 extern void tty_buffer_flush_work(struct tty_port *port);
472 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
473 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
474 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
475 speed_t ibaud, speed_t obaud);
476 extern void tty_encode_baud_rate(struct tty_struct *tty,
477 speed_t ibaud, speed_t obaud);
478
479 /**
480 * tty_get_baud_rate - get tty bit rates
481 * @tty: tty to query
482 *
483 * Returns the baud rate as an integer for this terminal. The
484 * termios lock must be held by the caller and the terminal bit
485 * flags may be updated.
486 *
487 * Locking: none
488 */
tty_get_baud_rate(struct tty_struct * tty)489 static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
490 {
491 return tty_termios_baud_rate(&tty->termios);
492 }
493
494 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
495 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
496 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
497
498 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
499 extern void tty_ldisc_deref(struct tty_ldisc *);
500 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
501 extern void tty_ldisc_hangup(struct tty_struct *tty);
502 extern const struct file_operations tty_ldiscs_proc_fops;
503
504 extern void tty_wakeup(struct tty_struct *tty);
505 extern void tty_ldisc_flush(struct tty_struct *tty);
506
507 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
508 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
509 unsigned int cmd, unsigned long arg);
510 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
511 extern void tty_default_fops(struct file_operations *fops);
512 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx);
513 extern int tty_alloc_file(struct file *file);
514 extern void tty_add_file(struct tty_struct *tty, struct file *file);
515 extern void tty_free_file(struct file *file);
516 extern void free_tty_struct(struct tty_struct *tty);
517 extern void deinitialize_tty_struct(struct tty_struct *tty);
518 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
519 extern int tty_release(struct inode *inode, struct file *filp);
520 extern int tty_init_termios(struct tty_struct *tty);
521 extern int tty_standard_install(struct tty_driver *driver,
522 struct tty_struct *tty);
523
524 extern struct mutex tty_mutex;
525 extern spinlock_t tty_files_lock;
526
527 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
528
529 extern void tty_port_init(struct tty_port *port);
530 extern void tty_port_link_device(struct tty_port *port,
531 struct tty_driver *driver, unsigned index);
532 extern struct device *tty_port_register_device(struct tty_port *port,
533 struct tty_driver *driver, unsigned index,
534 struct device *device);
535 extern struct device *tty_port_register_device_attr(struct tty_port *port,
536 struct tty_driver *driver, unsigned index,
537 struct device *device, void *drvdata,
538 const struct attribute_group **attr_grp);
539 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
540 extern void tty_port_free_xmit_buf(struct tty_port *port);
541 extern void tty_port_destroy(struct tty_port *port);
542 extern void tty_port_put(struct tty_port *port);
543
tty_port_get(struct tty_port * port)544 static inline struct tty_port *tty_port_get(struct tty_port *port)
545 {
546 if (port && kref_get_unless_zero(&port->kref))
547 return port;
548 return NULL;
549 }
550
551 /* If the cts flow control is enabled, return true. */
tty_port_cts_enabled(struct tty_port * port)552 static inline bool tty_port_cts_enabled(struct tty_port *port)
553 {
554 return port->flags & ASYNC_CTS_FLOW;
555 }
556
557 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
558 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
559 extern int tty_port_carrier_raised(struct tty_port *port);
560 extern void tty_port_raise_dtr_rts(struct tty_port *port);
561 extern void tty_port_lower_dtr_rts(struct tty_port *port);
562 extern void tty_port_hangup(struct tty_port *port);
563 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
564 extern void tty_port_tty_wakeup(struct tty_port *port);
565 extern int tty_port_block_til_ready(struct tty_port *port,
566 struct tty_struct *tty, struct file *filp);
567 extern int tty_port_close_start(struct tty_port *port,
568 struct tty_struct *tty, struct file *filp);
569 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
570 extern void tty_port_close(struct tty_port *port,
571 struct tty_struct *tty, struct file *filp);
572 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
573 struct tty_struct *tty);
574 extern int tty_port_open(struct tty_port *port,
575 struct tty_struct *tty, struct file *filp);
tty_port_users(struct tty_port * port)576 static inline int tty_port_users(struct tty_port *port)
577 {
578 return port->count + port->blocked_open;
579 }
580
581 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
582 extern int tty_unregister_ldisc(int disc);
583 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
584 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
585 extern void tty_ldisc_release(struct tty_struct *tty);
586 extern void tty_ldisc_init(struct tty_struct *tty);
587 extern void tty_ldisc_deinit(struct tty_struct *tty);
588 extern void tty_ldisc_begin(void);
589
tty_ldisc_receive_buf(struct tty_ldisc * ld,unsigned char * p,char * f,int count)590 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p,
591 char *f, int count)
592 {
593 if (ld->ops->receive_buf2)
594 count = ld->ops->receive_buf2(ld->tty, p, f, count);
595 else {
596 count = min_t(int, count, ld->tty->receive_room);
597 if (count && ld->ops->receive_buf)
598 ld->ops->receive_buf(ld->tty, p, f, count);
599 }
600 return count;
601 }
602
603
604 /* n_tty.c */
605 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
606 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
607
608 /* tty_audit.c */
609 #ifdef CONFIG_AUDIT
610 extern void tty_audit_add_data(struct tty_struct *tty, const void *data,
611 size_t size, unsigned icanon);
612 extern void tty_audit_exit(void);
613 extern void tty_audit_fork(struct signal_struct *sig);
614 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
615 extern void tty_audit_push(struct tty_struct *tty);
616 extern int tty_audit_push_current(void);
617 #else
tty_audit_add_data(struct tty_struct * tty,const void * data,size_t size,unsigned icanon)618 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data,
619 size_t size, unsigned icanon)
620 {
621 }
tty_audit_tiocsti(struct tty_struct * tty,char ch)622 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
623 {
624 }
tty_audit_exit(void)625 static inline void tty_audit_exit(void)
626 {
627 }
tty_audit_fork(struct signal_struct * sig)628 static inline void tty_audit_fork(struct signal_struct *sig)
629 {
630 }
tty_audit_push(struct tty_struct * tty)631 static inline void tty_audit_push(struct tty_struct *tty)
632 {
633 }
tty_audit_push_current(void)634 static inline int tty_audit_push_current(void)
635 {
636 return 0;
637 }
638 #endif
639
640 /* tty_ioctl.c */
641 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
642 unsigned int cmd, unsigned long arg);
643 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
644 unsigned int cmd, unsigned long arg);
645
646 /* vt.c */
647
648 extern int vt_ioctl(struct tty_struct *tty,
649 unsigned int cmd, unsigned long arg);
650
651 extern long vt_compat_ioctl(struct tty_struct *tty,
652 unsigned int cmd, unsigned long arg);
653
654 /* tty_mutex.c */
655 /* functions for preparation of BKL removal */
656 extern void __lockfunc tty_lock(struct tty_struct *tty);
657 extern int tty_lock_interruptible(struct tty_struct *tty);
658 extern void __lockfunc tty_unlock(struct tty_struct *tty);
659 extern void __lockfunc tty_lock_slave(struct tty_struct *tty);
660 extern void __lockfunc tty_unlock_slave(struct tty_struct *tty);
661 extern void tty_set_lock_subclass(struct tty_struct *tty);
662
663 #ifdef CONFIG_PROC_FS
664 extern void proc_tty_register_driver(struct tty_driver *);
665 extern void proc_tty_unregister_driver(struct tty_driver *);
666 #else
proc_tty_register_driver(struct tty_driver * d)667 static inline void proc_tty_register_driver(struct tty_driver *d) {}
proc_tty_unregister_driver(struct tty_driver * d)668 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
669 #endif
670
671 #define tty_debug(tty, f, args...) \
672 do { \
673 printk(KERN_DEBUG "%s: %s: " f, __func__, \
674 tty_name(tty), ##args); \
675 } while (0)
676
677 #endif
678