tty.h revision be1bc2889a4db4961ef69f47fb471ecae9f23ade
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#ifdef __KERNEL__ 9#include <linux/fs.h> 10#include <linux/major.h> 11#include <linux/termios.h> 12#include <linux/workqueue.h> 13#include <linux/tty_driver.h> 14#include <linux/tty_ldisc.h> 15#include <linux/mutex.h> 16#include <linux/smp_lock.h> 17 18#include <asm/system.h> 19 20 21/* 22 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 23 * hardcoded at present.) 24 */ 25#define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 26#define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 27#define NR_LDISCS 30 28 29/* line disciplines */ 30#define N_TTY 0 31#define N_SLIP 1 32#define N_MOUSE 2 33#define N_PPP 3 34#define N_STRIP 4 35#define N_AX25 5 36#define N_X25 6 /* X.25 async */ 37#define N_6PACK 7 38#define N_MASC 8 /* Reserved for Mobitex module <kaz@cafe.net> */ 39#define N_R3964 9 /* Reserved for Simatic R3964 module */ 40#define N_PROFIBUS_FDL 10 /* Reserved for Profibus */ 41#define N_IRDA 11 /* Linux IrDa - http://irda.sourceforge.net/ */ 42#define N_SMSBLOCK 12 /* SMS block mode - for talking to GSM data */ 43 /* cards about SMS messages */ 44#define N_HDLC 13 /* synchronous HDLC */ 45#define N_SYNC_PPP 14 /* synchronous PPP */ 46#define N_HCI 15 /* Bluetooth HCI UART */ 47#define N_GIGASET_M101 16 /* Siemens Gigaset M101 serial DECT adapter */ 48#define N_SLCAN 17 /* Serial / USB serial CAN Adaptors */ 49#define N_PPS 18 /* Pulse per Second */ 50#define N_V253 19 /* Codec control over voice modem */ 51#define N_CAIF 20 /* CAIF protocol for talking to modems */ 52#define N_GSM0710 21 /* GSM 0710 Mux */ 53 54/* 55 * This character is the same as _POSIX_VDISABLE: it cannot be used as 56 * a c_cc[] character, but indicates that a particular special character 57 * isn't in use (eg VINTR has no character etc) 58 */ 59#define __DISABLED_CHAR '\0' 60 61struct tty_buffer { 62 struct tty_buffer *next; 63 char *char_buf_ptr; 64 unsigned char *flag_buf_ptr; 65 int used; 66 int size; 67 int commit; 68 int read; 69 /* Data points here */ 70 unsigned long data[0]; 71}; 72 73/* 74 * We default to dicing tty buffer allocations to this many characters 75 * in order to avoid multiple page allocations. We know the size of 76 * tty_buffer itself but it must also be taken into account that the 77 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation 78 * logic this must match 79 */ 80 81#define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF) 82 83 84struct tty_bufhead { 85 struct delayed_work work; 86 spinlock_t lock; 87 struct tty_buffer *head; /* Queue head */ 88 struct tty_buffer *tail; /* Active buffer */ 89 struct tty_buffer *free; /* Free queue head */ 90 int memory_used; /* Buffer space used excluding 91 free queue */ 92}; 93/* 94 * When a break, frame error, or parity error happens, these codes are 95 * stuffed into the flags buffer. 96 */ 97#define TTY_NORMAL 0 98#define TTY_BREAK 1 99#define TTY_FRAME 2 100#define TTY_PARITY 3 101#define TTY_OVERRUN 4 102 103#define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR]) 104#define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT]) 105#define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE]) 106#define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL]) 107#define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF]) 108#define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME]) 109#define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN]) 110#define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC]) 111#define START_CHAR(tty) ((tty)->termios->c_cc[VSTART]) 112#define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP]) 113#define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP]) 114#define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL]) 115#define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT]) 116#define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD]) 117#define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE]) 118#define LNEXT_CHAR(tty) ((tty)->termios->c_cc[VLNEXT]) 119#define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2]) 120 121#define _I_FLAG(tty, f) ((tty)->termios->c_iflag & (f)) 122#define _O_FLAG(tty, f) ((tty)->termios->c_oflag & (f)) 123#define _C_FLAG(tty, f) ((tty)->termios->c_cflag & (f)) 124#define _L_FLAG(tty, f) ((tty)->termios->c_lflag & (f)) 125 126#define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 127#define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 128#define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 129#define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 130#define I_INPCK(tty) _I_FLAG((tty), INPCK) 131#define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 132#define I_INLCR(tty) _I_FLAG((tty), INLCR) 133#define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 134#define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 135#define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 136#define I_IXON(tty) _I_FLAG((tty), IXON) 137#define I_IXANY(tty) _I_FLAG((tty), IXANY) 138#define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 139#define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 140#define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 141 142#define O_OPOST(tty) _O_FLAG((tty), OPOST) 143#define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 144#define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 145#define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 146#define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 147#define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 148#define O_OFILL(tty) _O_FLAG((tty), OFILL) 149#define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 150#define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 151#define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 152#define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 153#define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 154#define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 155#define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 156 157#define C_BAUD(tty) _C_FLAG((tty), CBAUD) 158#define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 159#define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 160#define C_CREAD(tty) _C_FLAG((tty), CREAD) 161#define C_PARENB(tty) _C_FLAG((tty), PARENB) 162#define C_PARODD(tty) _C_FLAG((tty), PARODD) 163#define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 164#define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 165#define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 166#define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 167 168#define L_ISIG(tty) _L_FLAG((tty), ISIG) 169#define L_ICANON(tty) _L_FLAG((tty), ICANON) 170#define L_XCASE(tty) _L_FLAG((tty), XCASE) 171#define L_ECHO(tty) _L_FLAG((tty), ECHO) 172#define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 173#define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 174#define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 175#define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 176#define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 177#define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 178#define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 179#define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 180#define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 181#define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 182#define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 183#define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 184 185struct device; 186struct signal_struct; 187 188/* 189 * Port level information. Each device keeps its own port level information 190 * so provide a common structure for those ports wanting to use common support 191 * routines. 192 * 193 * The tty port has a different lifetime to the tty so must be kept apart. 194 * In addition be careful as tty -> port mappings are valid for the life 195 * of the tty object but in many cases port -> tty mappings are valid only 196 * until a hangup so don't use the wrong path. 197 */ 198 199struct tty_port; 200 201struct tty_port_operations { 202 /* Return 1 if the carrier is raised */ 203 int (*carrier_raised)(struct tty_port *port); 204 /* Control the DTR line */ 205 void (*dtr_rts)(struct tty_port *port, int raise); 206 /* Called when the last close completes or a hangup finishes 207 IFF the port was initialized. Do not use to free resources. Called 208 under the port mutex to serialize against activate/shutdowns */ 209 void (*shutdown)(struct tty_port *port); 210 void (*drop)(struct tty_port *port); 211 /* Called under the port mutex from tty_port_open, serialized using 212 the port mutex */ 213 /* FIXME: long term getting the tty argument *out* of this would be 214 good for consoles */ 215 int (*activate)(struct tty_port *port, struct tty_struct *tty); 216 /* Called on the final put of a port */ 217 void (*destruct)(struct tty_port *port); 218}; 219 220struct tty_port { 221 struct tty_struct *tty; /* Back pointer */ 222 const struct tty_port_operations *ops; /* Port operations */ 223 spinlock_t lock; /* Lock protecting tty field */ 224 int blocked_open; /* Waiting to open */ 225 int count; /* Usage count */ 226 wait_queue_head_t open_wait; /* Open waiters */ 227 wait_queue_head_t close_wait; /* Close waiters */ 228 wait_queue_head_t delta_msr_wait; /* Modem status change */ 229 unsigned long flags; /* TTY flags ASY_*/ 230 unsigned char console:1; /* port is a console */ 231 struct mutex mutex; /* Locking */ 232 struct mutex buf_mutex; /* Buffer alloc lock */ 233 unsigned char *xmit_buf; /* Optional buffer */ 234 unsigned int close_delay; /* Close port delay */ 235 unsigned int closing_wait; /* Delay for output */ 236 int drain_delay; /* Set to zero if no pure time 237 based drain is needed else 238 set to size of fifo */ 239 struct kref kref; /* Ref counter */ 240}; 241 242/* 243 * Where all of the state associated with a tty is kept while the tty 244 * is open. Since the termios state should be kept even if the tty 245 * has been closed --- for things like the baud rate, etc --- it is 246 * not stored here, but rather a pointer to the real state is stored 247 * here. Possible the winsize structure should have the same 248 * treatment, but (1) the default 80x24 is usually right and (2) it's 249 * most often used by a windowing system, which will set the correct 250 * size each time the window is created or resized anyway. 251 * - TYT, 9/14/92 252 */ 253 254struct tty_operations; 255 256struct tty_struct { 257 int magic; 258 struct kref kref; 259 struct tty_driver *driver; 260 const struct tty_operations *ops; 261 int index; 262 263 /* Protects ldisc changes: Lock tty not pty */ 264 struct mutex ldisc_mutex; 265 struct tty_ldisc *ldisc; 266 267 struct mutex termios_mutex; 268 spinlock_t ctrl_lock; 269 /* Termios values are protected by the termios mutex */ 270 struct ktermios *termios, *termios_locked; 271 struct termiox *termiox; /* May be NULL for unsupported */ 272 char name[64]; 273 struct pid *pgrp; /* Protected by ctrl lock */ 274 struct pid *session; 275 unsigned long flags; 276 int count; 277 struct winsize winsize; /* termios mutex */ 278 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; 279 unsigned char low_latency:1, warned:1; 280 unsigned char ctrl_status; /* ctrl_lock */ 281 unsigned int receive_room; /* Bytes free for queue */ 282 283 struct tty_struct *link; 284 struct fasync_struct *fasync; 285 struct tty_bufhead buf; /* Locked internally */ 286 int alt_speed; /* For magic substitution of 38400 bps */ 287 wait_queue_head_t write_wait; 288 wait_queue_head_t read_wait; 289 struct work_struct hangup_work; 290 void *disc_data; 291 void *driver_data; 292 struct list_head tty_files; 293 294#define N_TTY_BUF_SIZE 4096 295 296 /* 297 * The following is data for the N_TTY line discipline. For 298 * historical reasons, this is included in the tty structure. 299 * Mostly locked by the BKL. 300 */ 301 unsigned int column; 302 unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1; 303 unsigned char closing:1; 304 unsigned char echo_overrun:1; 305 unsigned short minimum_to_wake; 306 unsigned long overrun_time; 307 int num_overrun; 308 unsigned long process_char_map[256/(8*sizeof(unsigned long))]; 309 char *read_buf; 310 int read_head; 311 int read_tail; 312 int read_cnt; 313 unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))]; 314 unsigned char *echo_buf; 315 unsigned int echo_pos; 316 unsigned int echo_cnt; 317 int canon_data; 318 unsigned long canon_head; 319 unsigned int canon_column; 320 struct mutex atomic_read_lock; 321 struct mutex atomic_write_lock; 322 struct mutex output_lock; 323 struct mutex echo_lock; 324 unsigned char *write_buf; 325 int write_cnt; 326 spinlock_t read_lock; 327 /* If the tty has a pending do_SAK, queue it here - akpm */ 328 struct work_struct SAK_work; 329 struct tty_port *port; 330}; 331 332/* tty magic number */ 333#define TTY_MAGIC 0x5401 334 335/* 336 * These bits are used in the flags field of the tty structure. 337 * 338 * So that interrupts won't be able to mess up the queues, 339 * copy_to_cooked must be atomic with respect to itself, as must 340 * tty->write. Thus, you must use the inline functions set_bit() and 341 * clear_bit() to make things atomic. 342 */ 343#define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 344#define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 345#define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 346#define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 347#define TTY_DEBUG 4 /* Debugging */ 348#define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 349#define TTY_PUSH 6 /* n_tty private */ 350#define TTY_CLOSING 7 /* ->close() in progress */ 351#define TTY_LDISC 9 /* Line discipline attached */ 352#define TTY_LDISC_CHANGING 10 /* Line discipline changing */ 353#define TTY_LDISC_OPEN 11 /* Line discipline is open */ 354#define TTY_HW_COOK_OUT 14 /* Hardware can do output cooking */ 355#define TTY_HW_COOK_IN 15 /* Hardware can do input cooking */ 356#define TTY_PTY_LOCK 16 /* pty private */ 357#define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 358#define TTY_HUPPED 18 /* Post driver->hangup() */ 359#define TTY_FLUSHING 19 /* Flushing to ldisc in progress */ 360#define TTY_FLUSHPENDING 20 /* Queued buffer flush pending */ 361 362#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 363 364extern void tty_write_flush(struct tty_struct *); 365 366extern struct ktermios tty_std_termios; 367 368extern void console_init(void); 369extern int vcs_init(void); 370 371extern struct class *tty_class; 372 373/** 374 * tty_kref_get - get a tty reference 375 * @tty: tty device 376 * 377 * Return a new reference to a tty object. The caller must hold 378 * sufficient locks/counts to ensure that their existing reference cannot 379 * go away 380 */ 381 382static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 383{ 384 if (tty) 385 kref_get(&tty->kref); 386 return tty; 387} 388extern void tty_kref_put(struct tty_struct *tty); 389 390extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 391 const char *routine); 392extern char *tty_name(struct tty_struct *tty, char *buf); 393extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 394extern int tty_check_change(struct tty_struct *tty); 395extern void stop_tty(struct tty_struct *tty); 396extern void start_tty(struct tty_struct *tty); 397extern int tty_register_driver(struct tty_driver *driver); 398extern int tty_unregister_driver(struct tty_driver *driver); 399extern struct device *tty_register_device(struct tty_driver *driver, 400 unsigned index, struct device *dev); 401extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 402extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 403 int buflen); 404extern void tty_write_message(struct tty_struct *tty, char *msg); 405extern int tty_put_char(struct tty_struct *tty, unsigned char c); 406extern int tty_chars_in_buffer(struct tty_struct *tty); 407extern int tty_write_room(struct tty_struct *tty); 408extern void tty_driver_flush_buffer(struct tty_struct *tty); 409extern void tty_throttle(struct tty_struct *tty); 410extern void tty_unthrottle(struct tty_struct *tty); 411extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 412extern void tty_shutdown(struct tty_struct *tty); 413extern void tty_free_termios(struct tty_struct *tty); 414extern int is_current_pgrp_orphaned(void); 415extern struct pid *tty_get_pgrp(struct tty_struct *tty); 416extern int is_ignored(int sig); 417extern int tty_signal(int sig, struct tty_struct *tty); 418extern void tty_hangup(struct tty_struct *tty); 419extern void tty_vhangup(struct tty_struct *tty); 420extern void tty_vhangup_self(void); 421extern void tty_unhangup(struct file *filp); 422extern int tty_hung_up_p(struct file *filp); 423extern void do_SAK(struct tty_struct *tty); 424extern void __do_SAK(struct tty_struct *tty); 425extern void disassociate_ctty(int priv); 426extern void no_tty(void); 427extern void tty_flip_buffer_push(struct tty_struct *tty); 428extern void tty_flush_to_ldisc(struct tty_struct *tty); 429extern void tty_buffer_free_all(struct tty_struct *tty); 430extern void tty_buffer_flush(struct tty_struct *tty); 431extern void tty_buffer_init(struct tty_struct *tty); 432extern speed_t tty_get_baud_rate(struct tty_struct *tty); 433extern speed_t tty_termios_baud_rate(struct ktermios *termios); 434extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 435extern void tty_termios_encode_baud_rate(struct ktermios *termios, 436 speed_t ibaud, speed_t obaud); 437extern void tty_encode_baud_rate(struct tty_struct *tty, 438 speed_t ibaud, speed_t obaud); 439extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 440extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 441 442extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 443extern void tty_ldisc_deref(struct tty_ldisc *); 444extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 445extern void tty_ldisc_hangup(struct tty_struct *tty); 446extern const struct file_operations tty_ldiscs_proc_fops; 447 448extern void tty_wakeup(struct tty_struct *tty); 449extern void tty_ldisc_flush(struct tty_struct *tty); 450 451extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 452extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 453 unsigned int cmd, unsigned long arg); 454extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 455extern dev_t tty_devnum(struct tty_struct *tty); 456extern void proc_clear_tty(struct task_struct *p); 457extern struct tty_struct *get_current_tty(void); 458extern void tty_default_fops(struct file_operations *fops); 459extern struct tty_struct *alloc_tty_struct(void); 460extern void free_tty_struct(struct tty_struct *tty); 461extern void initialize_tty_struct(struct tty_struct *tty, 462 struct tty_driver *driver, int idx); 463extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx, 464 int first_ok); 465extern int tty_release(struct inode *inode, struct file *filp); 466extern int tty_init_termios(struct tty_struct *tty); 467 468extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 469extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 470 471extern struct mutex tty_mutex; 472 473extern void tty_write_unlock(struct tty_struct *tty); 474extern int tty_write_lock(struct tty_struct *tty, int ndelay); 475#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 476 477extern void tty_port_init(struct tty_port *port); 478extern int tty_port_alloc_xmit_buf(struct tty_port *port); 479extern void tty_port_free_xmit_buf(struct tty_port *port); 480extern void tty_port_put(struct tty_port *port); 481 482static inline struct tty_port *tty_port_get(struct tty_port *port) 483{ 484 if (port) 485 kref_get(&port->kref); 486 return port; 487} 488 489extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 490extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 491extern int tty_port_carrier_raised(struct tty_port *port); 492extern void tty_port_raise_dtr_rts(struct tty_port *port); 493extern void tty_port_lower_dtr_rts(struct tty_port *port); 494extern void tty_port_hangup(struct tty_port *port); 495extern int tty_port_block_til_ready(struct tty_port *port, 496 struct tty_struct *tty, struct file *filp); 497extern int tty_port_close_start(struct tty_port *port, 498 struct tty_struct *tty, struct file *filp); 499extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 500extern void tty_port_close(struct tty_port *port, 501 struct tty_struct *tty, struct file *filp); 502extern int tty_port_open(struct tty_port *port, 503 struct tty_struct *tty, struct file *filp); 504static inline int tty_port_users(struct tty_port *port) 505{ 506 return port->count + port->blocked_open; 507} 508 509extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 510extern int tty_unregister_ldisc(int disc); 511extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 512extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 513extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 514extern void tty_ldisc_init(struct tty_struct *tty); 515extern void tty_ldisc_begin(void); 516/* This last one is just for the tty layer internals and shouldn't be used elsewhere */ 517extern void tty_ldisc_enable(struct tty_struct *tty); 518 519 520/* n_tty.c */ 521extern struct tty_ldisc_ops tty_ldisc_N_TTY; 522extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 523 524/* tty_audit.c */ 525#ifdef CONFIG_AUDIT 526extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 527 size_t size); 528extern void tty_audit_exit(void); 529extern void tty_audit_fork(struct signal_struct *sig); 530extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 531extern void tty_audit_push(struct tty_struct *tty); 532extern void tty_audit_push_task(struct task_struct *tsk, 533 uid_t loginuid, u32 sessionid); 534#else 535static inline void tty_audit_add_data(struct tty_struct *tty, 536 unsigned char *data, size_t size) 537{ 538} 539static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 540{ 541} 542static inline void tty_audit_exit(void) 543{ 544} 545static inline void tty_audit_fork(struct signal_struct *sig) 546{ 547} 548static inline void tty_audit_push(struct tty_struct *tty) 549{ 550} 551static inline void tty_audit_push_task(struct task_struct *tsk, 552 uid_t loginuid, u32 sessionid) 553{ 554} 555#endif 556 557/* tty_io.c */ 558extern int __init tty_init(void); 559 560/* tty_ioctl.c */ 561extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 562 unsigned int cmd, unsigned long arg); 563 564/* serial.c */ 565 566extern void serial_console_init(void); 567 568/* pcxx.c */ 569 570extern int pcxe_open(struct tty_struct *tty, struct file *filp); 571 572/* vt.c */ 573 574extern int vt_ioctl(struct tty_struct *tty, struct file *file, 575 unsigned int cmd, unsigned long arg); 576 577extern long vt_compat_ioctl(struct tty_struct *tty, struct file * file, 578 unsigned int cmd, unsigned long arg); 579 580/* functions for preparation of BKL removal */ 581 582/* 583 * tty_lock_nested get the tty_lock while potentially holding it 584 * 585 * The Big TTY Mutex is a recursive lock, meaning you can take it 586 * from a thread that is already holding it. 587 * This is bad for a number of reasons, so tty_lock_nested should 588 * really be used as rarely as possible. If a code location can 589 * be shown to never get called with this held already, it should 590 * use tty_lock() instead. 591 */ 592static inline void __lockfunc tty_lock_nested(void) __acquires(kernel_lock) 593{ 594 lock_kernel(); 595} 596static inline void tty_lock(void) __acquires(kernel_lock) 597{ 598#ifdef CONFIG_LOCK_KERNEL 599 /* kernel_locked is 1 for !CONFIG_LOCK_KERNEL */ 600 WARN_ON(kernel_locked()); 601#endif 602 lock_kernel(); 603} 604static inline void tty_unlock(void) __releases(kernel_lock) 605{ 606 unlock_kernel(); 607} 608#define tty_locked() (kernel_locked()) 609 610/* 611 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 612 * 613 * The condition we are waiting for might take a long time to 614 * become true, or might depend on another thread taking the 615 * BTM. In either case, we need to drop the BTM to guarantee 616 * forward progress. This is a leftover from the conversion 617 * from the BKL and should eventually get removed as the BTM 618 * falls out of use. 619 * 620 * Do not use in new code. 621 */ 622#define wait_event_interruptible_tty(wq, condition) \ 623({ \ 624 int __ret = 0; \ 625 if (!(condition)) { \ 626 __wait_event_interruptible_tty(wq, condition, __ret); \ 627 } \ 628 __ret; \ 629}) 630 631#define __wait_event_interruptible_tty(wq, condition, ret) \ 632do { \ 633 DEFINE_WAIT(__wait); \ 634 \ 635 for (;;) { \ 636 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ 637 if (condition) \ 638 break; \ 639 if (!signal_pending(current)) { \ 640 tty_unlock(); \ 641 schedule(); \ 642 tty_lock(); \ 643 continue; \ 644 } \ 645 ret = -ERESTARTSYS; \ 646 break; \ 647 } \ 648 finish_wait(&wq, &__wait); \ 649} while (0) 650 651 652#endif /* __KERNEL__ */ 653#endif 654