tty: rework pty count limiting
[deliverable/linux.git] / include / linux / tty.h
1 #ifndef _LINUX_TTY_H
2 #define _LINUX_TTY_H
3
4 /*
5 * 'tty.h' defines some structures used by tty_io.c and some defines.
6 */
7
8 #define NR_LDISCS 30
9
10 /* line disciplines */
11 #define N_TTY 0
12 #define N_SLIP 1
13 #define N_MOUSE 2
14 #define N_PPP 3
15 #define N_STRIP 4
16 #define N_AX25 5
17 #define N_X25 6 /* X.25 async */
18 #define N_6PACK 7
19 #define N_MASC 8 /* Reserved for Mobitex module <kaz@cafe.net> */
20 #define N_R3964 9 /* Reserved for Simatic R3964 module */
21 #define N_PROFIBUS_FDL 10 /* Reserved for Profibus */
22 #define N_IRDA 11 /* Linux IrDa - http://irda.sourceforge.net/ */
23 #define N_SMSBLOCK 12 /* SMS block mode - for talking to GSM data */
24 /* cards about SMS messages */
25 #define N_HDLC 13 /* synchronous HDLC */
26 #define N_SYNC_PPP 14 /* synchronous PPP */
27 #define N_HCI 15 /* Bluetooth HCI UART */
28 #define N_GIGASET_M101 16 /* Siemens Gigaset M101 serial DECT adapter */
29 #define N_SLCAN 17 /* Serial / USB serial CAN Adaptors */
30 #define N_PPS 18 /* Pulse per Second */
31 #define N_V253 19 /* Codec control over voice modem */
32 #define N_CAIF 20 /* CAIF protocol for talking to modems */
33 #define N_GSM0710 21 /* GSM 0710 Mux */
34 #define N_TI_WL 22 /* for TI's WL BT, FM, GPS combo chips */
35 #define N_TRACESINK 23 /* Trace data routing for MIPI P1149.7 */
36 #define N_TRACEROUTER 24 /* Trace data routing for MIPI P1149.7 */
37
38 #ifdef __KERNEL__
39 #include <linux/fs.h>
40 #include <linux/major.h>
41 #include <linux/termios.h>
42 #include <linux/workqueue.h>
43 #include <linux/tty_driver.h>
44 #include <linux/tty_ldisc.h>
45 #include <linux/mutex.h>
46
47 #include <asm/system.h>
48
49
50 /*
51 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
52 * hardcoded at present.)
53 */
54 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */
55 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */
56 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */
57
58 /*
59 * This character is the same as _POSIX_VDISABLE: it cannot be used as
60 * a c_cc[] character, but indicates that a particular special character
61 * isn't in use (eg VINTR has no character etc)
62 */
63 #define __DISABLED_CHAR '\0'
64
65 struct tty_buffer {
66 struct tty_buffer *next;
67 char *char_buf_ptr;
68 unsigned char *flag_buf_ptr;
69 int used;
70 int size;
71 int commit;
72 int read;
73 /* Data points here */
74 unsigned long data[0];
75 };
76
77 /*
78 * We default to dicing tty buffer allocations to this many characters
79 * in order to avoid multiple page allocations. We know the size of
80 * tty_buffer itself but it must also be taken into account that the
81 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
82 * logic this must match
83 */
84
85 #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
86
87
88 struct tty_bufhead {
89 struct work_struct work;
90 spinlock_t lock;
91 struct tty_buffer *head; /* Queue head */
92 struct tty_buffer *tail; /* Active buffer */
93 struct tty_buffer *free; /* Free queue head */
94 int memory_used; /* Buffer space used excluding
95 free queue */
96 };
97 /*
98 * When a break, frame error, or parity error happens, these codes are
99 * stuffed into the flags buffer.
100 */
101 #define TTY_NORMAL 0
102 #define TTY_BREAK 1
103 #define TTY_FRAME 2
104 #define TTY_PARITY 3
105 #define TTY_OVERRUN 4
106
107 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
108 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
109 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
110 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
111 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
112 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
113 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
114 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
115 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
116 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
117 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
118 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
119 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
120 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
121 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
122 #define LNEXT_CHAR(tty) ((tty)->termios->c_cc[VLNEXT])
123 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
124
125 #define _I_FLAG(tty, f) ((tty)->termios->c_iflag & (f))
126 #define _O_FLAG(tty, f) ((tty)->termios->c_oflag & (f))
127 #define _C_FLAG(tty, f) ((tty)->termios->c_cflag & (f))
128 #define _L_FLAG(tty, f) ((tty)->termios->c_lflag & (f))
129
130 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK)
131 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT)
132 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR)
133 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK)
134 #define I_INPCK(tty) _I_FLAG((tty), INPCK)
135 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP)
136 #define I_INLCR(tty) _I_FLAG((tty), INLCR)
137 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR)
138 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL)
139 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC)
140 #define I_IXON(tty) _I_FLAG((tty), IXON)
141 #define I_IXANY(tty) _I_FLAG((tty), IXANY)
142 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF)
143 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL)
144 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8)
145
146 #define O_OPOST(tty) _O_FLAG((tty), OPOST)
147 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC)
148 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR)
149 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL)
150 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR)
151 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET)
152 #define O_OFILL(tty) _O_FLAG((tty), OFILL)
153 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL)
154 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY)
155 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY)
156 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY)
157 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY)
158 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY)
159 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY)
160
161 #define C_BAUD(tty) _C_FLAG((tty), CBAUD)
162 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE)
163 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB)
164 #define C_CREAD(tty) _C_FLAG((tty), CREAD)
165 #define C_PARENB(tty) _C_FLAG((tty), PARENB)
166 #define C_PARODD(tty) _C_FLAG((tty), PARODD)
167 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL)
168 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL)
169 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD)
170 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS)
171
172 #define L_ISIG(tty) _L_FLAG((tty), ISIG)
173 #define L_ICANON(tty) _L_FLAG((tty), ICANON)
174 #define L_XCASE(tty) _L_FLAG((tty), XCASE)
175 #define L_ECHO(tty) _L_FLAG((tty), ECHO)
176 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE)
177 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK)
178 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL)
179 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH)
180 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP)
181 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL)
182 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT)
183 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE)
184 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO)
185 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN)
186 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN)
187 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC)
188
189 struct device;
190 struct signal_struct;
191
192 /*
193 * Port level information. Each device keeps its own port level information
194 * so provide a common structure for those ports wanting to use common support
195 * routines.
196 *
197 * The tty port has a different lifetime to the tty so must be kept apart.
198 * In addition be careful as tty -> port mappings are valid for the life
199 * of the tty object but in many cases port -> tty mappings are valid only
200 * until a hangup so don't use the wrong path.
201 */
202
203 struct tty_port;
204
205 struct tty_port_operations {
206 /* Return 1 if the carrier is raised */
207 int (*carrier_raised)(struct tty_port *port);
208 /* Control the DTR line */
209 void (*dtr_rts)(struct tty_port *port, int raise);
210 /* Called when the last close completes or a hangup finishes
211 IFF the port was initialized. Do not use to free resources. Called
212 under the port mutex to serialize against activate/shutdowns */
213 void (*shutdown)(struct tty_port *port);
214 void (*drop)(struct tty_port *port);
215 /* Called under the port mutex from tty_port_open, serialized using
216 the port mutex */
217 /* FIXME: long term getting the tty argument *out* of this would be
218 good for consoles */
219 int (*activate)(struct tty_port *port, struct tty_struct *tty);
220 /* Called on the final put of a port */
221 void (*destruct)(struct tty_port *port);
222 };
223
224 struct tty_port {
225 struct tty_struct *tty; /* Back pointer */
226 const struct tty_port_operations *ops; /* Port operations */
227 spinlock_t lock; /* Lock protecting tty field */
228 int blocked_open; /* Waiting to open */
229 int count; /* Usage count */
230 wait_queue_head_t open_wait; /* Open waiters */
231 wait_queue_head_t close_wait; /* Close waiters */
232 wait_queue_head_t delta_msr_wait; /* Modem status change */
233 unsigned long flags; /* TTY flags ASY_*/
234 unsigned char console:1; /* port is a console */
235 struct mutex mutex; /* Locking */
236 struct mutex buf_mutex; /* Buffer alloc lock */
237 unsigned char *xmit_buf; /* Optional buffer */
238 unsigned int close_delay; /* Close port delay */
239 unsigned int closing_wait; /* Delay for output */
240 int drain_delay; /* Set to zero if no pure time
241 based drain is needed else
242 set to size of fifo */
243 struct kref kref; /* Ref counter */
244 };
245
246 /*
247 * Where all of the state associated with a tty is kept while the tty
248 * is open. Since the termios state should be kept even if the tty
249 * has been closed --- for things like the baud rate, etc --- it is
250 * not stored here, but rather a pointer to the real state is stored
251 * here. Possible the winsize structure should have the same
252 * treatment, but (1) the default 80x24 is usually right and (2) it's
253 * most often used by a windowing system, which will set the correct
254 * size each time the window is created or resized anyway.
255 * - TYT, 9/14/92
256 */
257
258 struct tty_operations;
259
260 struct tty_struct {
261 int magic;
262 struct kref kref;
263 struct device *dev;
264 struct tty_driver *driver;
265 const struct tty_operations *ops;
266 int index;
267
268 /* Protects ldisc changes: Lock tty not pty */
269 struct mutex ldisc_mutex;
270 struct tty_ldisc *ldisc;
271
272 struct mutex termios_mutex;
273 spinlock_t ctrl_lock;
274 /* Termios values are protected by the termios mutex */
275 struct ktermios *termios, *termios_locked;
276 struct termiox *termiox; /* May be NULL for unsupported */
277 char name[64];
278 struct pid *pgrp; /* Protected by ctrl lock */
279 struct pid *session;
280 unsigned long flags;
281 int count;
282 struct winsize winsize; /* termios mutex */
283 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
284 unsigned char low_latency:1, warned:1;
285 unsigned char ctrl_status; /* ctrl_lock */
286 unsigned int receive_room; /* Bytes free for queue */
287
288 struct tty_struct *link;
289 struct fasync_struct *fasync;
290 struct tty_bufhead buf; /* Locked internally */
291 int alt_speed; /* For magic substitution of 38400 bps */
292 wait_queue_head_t write_wait;
293 wait_queue_head_t read_wait;
294 struct work_struct hangup_work;
295 void *disc_data;
296 void *driver_data;
297 struct list_head tty_files;
298
299 #define N_TTY_BUF_SIZE 4096
300
301 /*
302 * The following is data for the N_TTY line discipline. For
303 * historical reasons, this is included in the tty structure.
304 * Mostly locked by the BKL.
305 */
306 unsigned int column;
307 unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
308 unsigned char closing:1;
309 unsigned char echo_overrun:1;
310 unsigned short minimum_to_wake;
311 unsigned long overrun_time;
312 int num_overrun;
313 unsigned long process_char_map[256/(8*sizeof(unsigned long))];
314 char *read_buf;
315 int read_head;
316 int read_tail;
317 int read_cnt;
318 unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
319 unsigned char *echo_buf;
320 unsigned int echo_pos;
321 unsigned int echo_cnt;
322 int canon_data;
323 unsigned long canon_head;
324 unsigned int canon_column;
325 struct mutex atomic_read_lock;
326 struct mutex atomic_write_lock;
327 struct mutex output_lock;
328 struct mutex echo_lock;
329 unsigned char *write_buf;
330 int write_cnt;
331 spinlock_t read_lock;
332 /* If the tty has a pending do_SAK, queue it here - akpm */
333 struct work_struct SAK_work;
334 struct tty_port *port;
335 };
336
337 /* Each of a tty's open files has private_data pointing to tty_file_private */
338 struct tty_file_private {
339 struct tty_struct *tty;
340 struct file *file;
341 struct list_head list;
342 };
343
344 /* tty magic number */
345 #define TTY_MAGIC 0x5401
346
347 /*
348 * These bits are used in the flags field of the tty structure.
349 *
350 * So that interrupts won't be able to mess up the queues,
351 * copy_to_cooked must be atomic with respect to itself, as must
352 * tty->write. Thus, you must use the inline functions set_bit() and
353 * clear_bit() to make things atomic.
354 */
355 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */
356 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */
357 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */
358 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */
359 #define TTY_DEBUG 4 /* Debugging */
360 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */
361 #define TTY_PUSH 6 /* n_tty private */
362 #define TTY_CLOSING 7 /* ->close() in progress */
363 #define TTY_LDISC 9 /* Line discipline attached */
364 #define TTY_LDISC_CHANGING 10 /* Line discipline changing */
365 #define TTY_LDISC_OPEN 11 /* Line discipline is open */
366 #define TTY_HW_COOK_OUT 14 /* Hardware can do output cooking */
367 #define TTY_HW_COOK_IN 15 /* Hardware can do input cooking */
368 #define TTY_PTY_LOCK 16 /* pty private */
369 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */
370 #define TTY_HUPPED 18 /* Post driver->hangup() */
371 #define TTY_FLUSHING 19 /* Flushing to ldisc in progress */
372 #define TTY_FLUSHPENDING 20 /* Queued buffer flush pending */
373 #define TTY_HUPPING 21 /* ->hangup() in progress */
374
375 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
376
377 extern void tty_write_flush(struct tty_struct *);
378
379 extern struct ktermios tty_std_termios;
380
381 extern void console_init(void);
382 extern int vcs_init(void);
383
384 extern struct class *tty_class;
385
386 /**
387 * tty_kref_get - get a tty reference
388 * @tty: tty device
389 *
390 * Return a new reference to a tty object. The caller must hold
391 * sufficient locks/counts to ensure that their existing reference cannot
392 * go away
393 */
394
395 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
396 {
397 if (tty)
398 kref_get(&tty->kref);
399 return tty;
400 }
401 extern void tty_kref_put(struct tty_struct *tty);
402
403 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
404 const char *routine);
405 extern char *tty_name(struct tty_struct *tty, char *buf);
406 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
407 extern int tty_check_change(struct tty_struct *tty);
408 extern void stop_tty(struct tty_struct *tty);
409 extern void start_tty(struct tty_struct *tty);
410 extern int tty_register_driver(struct tty_driver *driver);
411 extern int tty_unregister_driver(struct tty_driver *driver);
412 extern struct device *tty_register_device(struct tty_driver *driver,
413 unsigned index, struct device *dev);
414 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
415 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
416 int buflen);
417 extern void tty_write_message(struct tty_struct *tty, char *msg);
418 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
419 extern int tty_chars_in_buffer(struct tty_struct *tty);
420 extern int tty_write_room(struct tty_struct *tty);
421 extern void tty_driver_flush_buffer(struct tty_struct *tty);
422 extern void tty_throttle(struct tty_struct *tty);
423 extern void tty_unthrottle(struct tty_struct *tty);
424 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
425 extern void tty_driver_remove_tty(struct tty_driver *driver,
426 struct tty_struct *tty);
427 extern void tty_shutdown(struct tty_struct *tty);
428 extern void tty_free_termios(struct tty_struct *tty);
429 extern int is_current_pgrp_orphaned(void);
430 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
431 extern int is_ignored(int sig);
432 extern int tty_signal(int sig, struct tty_struct *tty);
433 extern void tty_hangup(struct tty_struct *tty);
434 extern void tty_vhangup(struct tty_struct *tty);
435 extern void tty_vhangup_locked(struct tty_struct *tty);
436 extern void tty_vhangup_self(void);
437 extern void tty_unhangup(struct file *filp);
438 extern int tty_hung_up_p(struct file *filp);
439 extern void do_SAK(struct tty_struct *tty);
440 extern void __do_SAK(struct tty_struct *tty);
441 extern void disassociate_ctty(int priv);
442 extern void no_tty(void);
443 extern void tty_flip_buffer_push(struct tty_struct *tty);
444 extern void tty_flush_to_ldisc(struct tty_struct *tty);
445 extern void tty_buffer_free_all(struct tty_struct *tty);
446 extern void tty_buffer_flush(struct tty_struct *tty);
447 extern void tty_buffer_init(struct tty_struct *tty);
448 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
449 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
450 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
451 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
452 speed_t ibaud, speed_t obaud);
453 extern void tty_encode_baud_rate(struct tty_struct *tty,
454 speed_t ibaud, speed_t obaud);
455 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
456 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
457 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
458
459 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
460 extern void tty_ldisc_deref(struct tty_ldisc *);
461 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
462 extern void tty_ldisc_hangup(struct tty_struct *tty);
463 extern const struct file_operations tty_ldiscs_proc_fops;
464
465 extern void tty_wakeup(struct tty_struct *tty);
466 extern void tty_ldisc_flush(struct tty_struct *tty);
467
468 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
469 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
470 unsigned int cmd, unsigned long arg);
471 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
472 extern dev_t tty_devnum(struct tty_struct *tty);
473 extern void proc_clear_tty(struct task_struct *p);
474 extern struct tty_struct *get_current_tty(void);
475 extern void tty_default_fops(struct file_operations *fops);
476 extern struct tty_struct *alloc_tty_struct(void);
477 extern int tty_alloc_file(struct file *file);
478 extern void tty_add_file(struct tty_struct *tty, struct file *file);
479 extern void tty_free_file(struct file *file);
480 extern void free_tty_struct(struct tty_struct *tty);
481 extern void initialize_tty_struct(struct tty_struct *tty,
482 struct tty_driver *driver, int idx);
483 extern void deinitialize_tty_struct(struct tty_struct *tty);
484 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
485 extern int tty_release(struct inode *inode, struct file *filp);
486 extern int tty_init_termios(struct tty_struct *tty);
487
488 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
489 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
490
491 extern struct mutex tty_mutex;
492 extern spinlock_t tty_files_lock;
493
494 extern void tty_write_unlock(struct tty_struct *tty);
495 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
496 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock))
497
498 extern void tty_port_init(struct tty_port *port);
499 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
500 extern void tty_port_free_xmit_buf(struct tty_port *port);
501 extern void tty_port_put(struct tty_port *port);
502
503 static inline struct tty_port *tty_port_get(struct tty_port *port)
504 {
505 if (port)
506 kref_get(&port->kref);
507 return port;
508 }
509
510 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
511 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
512 extern int tty_port_carrier_raised(struct tty_port *port);
513 extern void tty_port_raise_dtr_rts(struct tty_port *port);
514 extern void tty_port_lower_dtr_rts(struct tty_port *port);
515 extern void tty_port_hangup(struct tty_port *port);
516 extern int tty_port_block_til_ready(struct tty_port *port,
517 struct tty_struct *tty, struct file *filp);
518 extern int tty_port_close_start(struct tty_port *port,
519 struct tty_struct *tty, struct file *filp);
520 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
521 extern void tty_port_close(struct tty_port *port,
522 struct tty_struct *tty, struct file *filp);
523 extern int tty_port_open(struct tty_port *port,
524 struct tty_struct *tty, struct file *filp);
525 static inline int tty_port_users(struct tty_port *port)
526 {
527 return port->count + port->blocked_open;
528 }
529
530 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
531 extern int tty_unregister_ldisc(int disc);
532 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
533 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
534 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
535 extern void tty_ldisc_init(struct tty_struct *tty);
536 extern void tty_ldisc_deinit(struct tty_struct *tty);
537 extern void tty_ldisc_begin(void);
538 /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
539 extern void tty_ldisc_enable(struct tty_struct *tty);
540
541
542 /* n_tty.c */
543 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
544 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
545
546 /* tty_audit.c */
547 #ifdef CONFIG_AUDIT
548 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
549 size_t size);
550 extern void tty_audit_exit(void);
551 extern void tty_audit_fork(struct signal_struct *sig);
552 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
553 extern void tty_audit_push(struct tty_struct *tty);
554 extern int tty_audit_push_task(struct task_struct *tsk,
555 uid_t loginuid, u32 sessionid);
556 #else
557 static inline void tty_audit_add_data(struct tty_struct *tty,
558 unsigned char *data, size_t size)
559 {
560 }
561 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
562 {
563 }
564 static inline void tty_audit_exit(void)
565 {
566 }
567 static inline void tty_audit_fork(struct signal_struct *sig)
568 {
569 }
570 static inline void tty_audit_push(struct tty_struct *tty)
571 {
572 }
573 static inline int tty_audit_push_task(struct task_struct *tsk,
574 uid_t loginuid, u32 sessionid)
575 {
576 return 0;
577 }
578 #endif
579
580 /* tty_io.c */
581 extern int __init tty_init(void);
582
583 /* tty_ioctl.c */
584 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
585 unsigned int cmd, unsigned long arg);
586 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
587 unsigned int cmd, unsigned long arg);
588
589 /* serial.c */
590
591 extern void serial_console_init(void);
592
593 /* pcxx.c */
594
595 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
596
597 /* vt.c */
598
599 extern int vt_ioctl(struct tty_struct *tty,
600 unsigned int cmd, unsigned long arg);
601
602 extern long vt_compat_ioctl(struct tty_struct *tty,
603 unsigned int cmd, unsigned long arg);
604
605 /* tty_mutex.c */
606 /* functions for preparation of BKL removal */
607 extern void __lockfunc tty_lock(void) __acquires(tty_lock);
608 extern void __lockfunc tty_unlock(void) __releases(tty_lock);
609
610 /*
611 * this shall be called only from where BTM is held (like close)
612 *
613 * We need this to ensure nobody waits for us to finish while we are waiting.
614 * Without this we were encountering system stalls.
615 *
616 * This should be indeed removed with BTM removal later.
617 *
618 * Locking: BTM required. Nobody is allowed to hold port->mutex.
619 */
620 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
621 long timeout)
622 {
623 tty_unlock(); /* tty->ops->close holds the BTM, drop it while waiting */
624 tty_wait_until_sent(tty, timeout);
625 tty_lock();
626 }
627
628 /*
629 * wait_event_interruptible_tty -- wait for a condition with the tty lock held
630 *
631 * The condition we are waiting for might take a long time to
632 * become true, or might depend on another thread taking the
633 * BTM. In either case, we need to drop the BTM to guarantee
634 * forward progress. This is a leftover from the conversion
635 * from the BKL and should eventually get removed as the BTM
636 * falls out of use.
637 *
638 * Do not use in new code.
639 */
640 #define wait_event_interruptible_tty(wq, condition) \
641 ({ \
642 int __ret = 0; \
643 if (!(condition)) { \
644 __wait_event_interruptible_tty(wq, condition, __ret); \
645 } \
646 __ret; \
647 })
648
649 #define __wait_event_interruptible_tty(wq, condition, ret) \
650 do { \
651 DEFINE_WAIT(__wait); \
652 \
653 for (;;) { \
654 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
655 if (condition) \
656 break; \
657 if (!signal_pending(current)) { \
658 tty_unlock(); \
659 schedule(); \
660 tty_lock(); \
661 continue; \
662 } \
663 ret = -ERESTARTSYS; \
664 break; \
665 } \
666 finish_wait(&wq, &__wait); \
667 } while (0)
668
669
670 #endif /* __KERNEL__ */
671 #endif
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