tty.h revision 6aad04f21374633bd8cecf25024553d1e11a9522
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 14 15 16/* 17 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 18 * hardcoded at present.) 19 */ 20#define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 21#define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 22#define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 23 24/* 25 * This character is the same as _POSIX_VDISABLE: it cannot be used as 26 * a c_cc[] character, but indicates that a particular special character 27 * isn't in use (eg VINTR has no character etc) 28 */ 29#define __DISABLED_CHAR '\0' 30 31struct tty_buffer { 32 struct tty_buffer *next; 33 char *char_buf_ptr; 34 unsigned char *flag_buf_ptr; 35 int used; 36 int size; 37 int commit; 38 int read; 39 /* Data points here */ 40 unsigned long data[0]; 41}; 42 43/* 44 * We default to dicing tty buffer allocations to this many characters 45 * in order to avoid multiple page allocations. We know the size of 46 * tty_buffer itself but it must also be taken into account that the 47 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation 48 * logic this must match 49 */ 50 51#define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF) 52 53 54struct tty_bufhead { 55 struct work_struct work; 56 spinlock_t lock; 57 struct tty_buffer *head; /* Queue head */ 58 struct tty_buffer *tail; /* Active buffer */ 59 struct tty_buffer *free; /* Free queue head */ 60 int memory_used; /* Buffer space used excluding 61 free queue */ 62}; 63/* 64 * When a break, frame error, or parity error happens, these codes are 65 * stuffed into the flags buffer. 66 */ 67#define TTY_NORMAL 0 68#define TTY_BREAK 1 69#define TTY_FRAME 2 70#define TTY_PARITY 3 71#define TTY_OVERRUN 4 72 73#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 74#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 75#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 76#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 77#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 78#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 79#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 80#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 81#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 82#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 83#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 84#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 85#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 86#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 87#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 88#define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 89#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 90 91#define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 92#define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 93#define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 94#define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 95 96#define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 97#define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 98#define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 99#define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 100#define I_INPCK(tty) _I_FLAG((tty), INPCK) 101#define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 102#define I_INLCR(tty) _I_FLAG((tty), INLCR) 103#define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 104#define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 105#define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 106#define I_IXON(tty) _I_FLAG((tty), IXON) 107#define I_IXANY(tty) _I_FLAG((tty), IXANY) 108#define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 109#define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 110#define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 111 112#define O_OPOST(tty) _O_FLAG((tty), OPOST) 113#define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 114#define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 115#define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 116#define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 117#define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 118#define O_OFILL(tty) _O_FLAG((tty), OFILL) 119#define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 120#define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 121#define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 122#define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 123#define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 124#define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 125#define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 126 127#define C_BAUD(tty) _C_FLAG((tty), CBAUD) 128#define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 129#define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 130#define C_CREAD(tty) _C_FLAG((tty), CREAD) 131#define C_PARENB(tty) _C_FLAG((tty), PARENB) 132#define C_PARODD(tty) _C_FLAG((tty), PARODD) 133#define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 134#define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 135#define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 136#define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 137 138#define L_ISIG(tty) _L_FLAG((tty), ISIG) 139#define L_ICANON(tty) _L_FLAG((tty), ICANON) 140#define L_XCASE(tty) _L_FLAG((tty), XCASE) 141#define L_ECHO(tty) _L_FLAG((tty), ECHO) 142#define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 143#define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 144#define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 145#define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 146#define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 147#define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 148#define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 149#define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 150#define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 151#define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 152#define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 153#define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 154 155struct device; 156struct signal_struct; 157 158/* 159 * Port level information. Each device keeps its own port level information 160 * so provide a common structure for those ports wanting to use common support 161 * routines. 162 * 163 * The tty port has a different lifetime to the tty so must be kept apart. 164 * In addition be careful as tty -> port mappings are valid for the life 165 * of the tty object but in many cases port -> tty mappings are valid only 166 * until a hangup so don't use the wrong path. 167 */ 168 169struct tty_port; 170 171struct tty_port_operations { 172 /* Return 1 if the carrier is raised */ 173 int (*carrier_raised)(struct tty_port *port); 174 /* Control the DTR line */ 175 void (*dtr_rts)(struct tty_port *port, int raise); 176 /* Called when the last close completes or a hangup finishes 177 IFF the port was initialized. Do not use to free resources. Called 178 under the port mutex to serialize against activate/shutdowns */ 179 void (*shutdown)(struct tty_port *port); 180 void (*drop)(struct tty_port *port); 181 /* Called under the port mutex from tty_port_open, serialized using 182 the port mutex */ 183 /* FIXME: long term getting the tty argument *out* of this would be 184 good for consoles */ 185 int (*activate)(struct tty_port *port, struct tty_struct *tty); 186 /* Called on the final put of a port */ 187 void (*destruct)(struct tty_port *port); 188}; 189 190struct tty_port { 191 struct tty_bufhead buf; /* Locked internally */ 192 struct tty_struct *tty; /* Back pointer */ 193 struct tty_struct *itty; /* internal back ptr */ 194 const struct tty_port_operations *ops; /* Port operations */ 195 spinlock_t lock; /* Lock protecting tty field */ 196 int blocked_open; /* Waiting to open */ 197 int count; /* Usage count */ 198 wait_queue_head_t open_wait; /* Open waiters */ 199 wait_queue_head_t close_wait; /* Close waiters */ 200 wait_queue_head_t delta_msr_wait; /* Modem status change */ 201 unsigned long flags; /* TTY flags ASY_*/ 202 unsigned long iflags; /* TTYP_ internal flags */ 203#define TTYP_FLUSHING 1 /* Flushing to ldisc in progress */ 204#define TTYP_FLUSHPENDING 2 /* Queued buffer flush pending */ 205 unsigned char console:1, /* port is a console */ 206 low_latency:1; /* direct buffer flush */ 207 struct mutex mutex; /* Locking */ 208 struct mutex buf_mutex; /* Buffer alloc lock */ 209 unsigned char *xmit_buf; /* Optional buffer */ 210 unsigned int close_delay; /* Close port delay */ 211 unsigned int closing_wait; /* Delay for output */ 212 int drain_delay; /* Set to zero if no pure time 213 based drain is needed else 214 set to size of fifo */ 215 struct kref kref; /* Ref counter */ 216}; 217 218/* 219 * Where all of the state associated with a tty is kept while the tty 220 * is open. Since the termios state should be kept even if the tty 221 * has been closed --- for things like the baud rate, etc --- it is 222 * not stored here, but rather a pointer to the real state is stored 223 * here. Possible the winsize structure should have the same 224 * treatment, but (1) the default 80x24 is usually right and (2) it's 225 * most often used by a windowing system, which will set the correct 226 * size each time the window is created or resized anyway. 227 * - TYT, 9/14/92 228 */ 229 230struct tty_operations; 231 232struct tty_struct { 233 int magic; 234 struct kref kref; 235 struct device *dev; 236 struct tty_driver *driver; 237 const struct tty_operations *ops; 238 int index; 239 240 /* Protects ldisc changes: Lock tty not pty */ 241 struct mutex ldisc_mutex; 242 struct tty_ldisc *ldisc; 243 244 struct mutex atomic_write_lock; 245 struct mutex legacy_mutex; 246 struct mutex termios_mutex; 247 spinlock_t ctrl_lock; 248 /* Termios values are protected by the termios mutex */ 249 struct ktermios termios, termios_locked; 250 struct termiox *termiox; /* May be NULL for unsupported */ 251 char name[64]; 252 struct pid *pgrp; /* Protected by ctrl lock */ 253 struct pid *session; 254 unsigned long flags; 255 int count; 256 struct winsize winsize; /* termios mutex */ 257 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; 258 unsigned char ctrl_status; /* ctrl_lock */ 259 unsigned int receive_room; /* Bytes free for queue */ 260 int flow_change; 261 262 struct tty_struct *link; 263 struct fasync_struct *fasync; 264 int alt_speed; /* For magic substitution of 38400 bps */ 265 wait_queue_head_t write_wait; 266 wait_queue_head_t read_wait; 267 struct work_struct hangup_work; 268 void *disc_data; 269 void *driver_data; 270 struct list_head tty_files; 271 272#define N_TTY_BUF_SIZE 4096 273 274 unsigned char closing:1; 275 unsigned short minimum_to_wake; 276 unsigned char *write_buf; 277 int write_cnt; 278 /* If the tty has a pending do_SAK, queue it here - akpm */ 279 struct work_struct SAK_work; 280 struct tty_port *port; 281}; 282 283/* Each of a tty's open files has private_data pointing to tty_file_private */ 284struct tty_file_private { 285 struct tty_struct *tty; 286 struct file *file; 287 struct list_head list; 288}; 289 290/* tty magic number */ 291#define TTY_MAGIC 0x5401 292 293/* 294 * These bits are used in the flags field of the tty structure. 295 * 296 * So that interrupts won't be able to mess up the queues, 297 * copy_to_cooked must be atomic with respect to itself, as must 298 * tty->write. Thus, you must use the inline functions set_bit() and 299 * clear_bit() to make things atomic. 300 */ 301#define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 302#define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 303#define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 304#define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 305#define TTY_DEBUG 4 /* Debugging */ 306#define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 307#define TTY_PUSH 6 /* n_tty private */ 308#define TTY_CLOSING 7 /* ->close() in progress */ 309#define TTY_LDISC 9 /* Line discipline attached */ 310#define TTY_LDISC_CHANGING 10 /* Line discipline changing */ 311#define TTY_LDISC_OPEN 11 /* Line discipline is open */ 312#define TTY_HW_COOK_OUT 14 /* Hardware can do output cooking */ 313#define TTY_HW_COOK_IN 15 /* Hardware can do input cooking */ 314#define TTY_PTY_LOCK 16 /* pty private */ 315#define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 316#define TTY_HUPPED 18 /* Post driver->hangup() */ 317#define TTY_HUPPING 21 /* ->hangup() in progress */ 318 319#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 320 321/* Values for tty->flow_change */ 322#define TTY_THROTTLE_SAFE 1 323#define TTY_UNTHROTTLE_SAFE 2 324 325static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 326{ 327 tty->flow_change = val; 328} 329 330static inline void tty_set_flow_change(struct tty_struct *tty, int val) 331{ 332 tty->flow_change = val; 333 smp_mb(); 334} 335 336#ifdef CONFIG_TTY 337extern void console_init(void); 338extern void tty_kref_put(struct tty_struct *tty); 339extern struct pid *tty_get_pgrp(struct tty_struct *tty); 340extern void tty_vhangup_self(void); 341extern void disassociate_ctty(int priv); 342extern dev_t tty_devnum(struct tty_struct *tty); 343extern void proc_clear_tty(struct task_struct *p); 344extern struct tty_struct *get_current_tty(void); 345/* tty_io.c */ 346extern int __init tty_init(void); 347#else 348static inline void console_init(void) 349{ } 350static inline void tty_kref_put(struct tty_struct *tty) 351{ } 352static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 353{ return NULL; } 354static inline void tty_vhangup_self(void) 355{ } 356static inline void disassociate_ctty(int priv) 357{ } 358static inline dev_t tty_devnum(struct tty_struct *tty) 359{ return 0; } 360static inline void proc_clear_tty(struct task_struct *p) 361{ } 362static inline struct tty_struct *get_current_tty(void) 363{ return NULL; } 364/* tty_io.c */ 365static inline int __init tty_init(void) 366{ return 0; } 367#endif 368 369extern void tty_write_flush(struct tty_struct *); 370 371extern struct ktermios tty_std_termios; 372 373extern int vcs_init(void); 374 375extern struct class *tty_class; 376 377/** 378 * tty_kref_get - get a tty reference 379 * @tty: tty device 380 * 381 * Return a new reference to a tty object. The caller must hold 382 * sufficient locks/counts to ensure that their existing reference cannot 383 * go away 384 */ 385 386static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 387{ 388 if (tty) 389 kref_get(&tty->kref); 390 return tty; 391} 392 393extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 394 const char *routine); 395extern char *tty_name(struct tty_struct *tty, char *buf); 396extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 397extern int tty_check_change(struct tty_struct *tty); 398extern void stop_tty(struct tty_struct *tty); 399extern void start_tty(struct tty_struct *tty); 400extern int tty_register_driver(struct tty_driver *driver); 401extern int tty_unregister_driver(struct tty_driver *driver); 402extern struct device *tty_register_device(struct tty_driver *driver, 403 unsigned index, struct device *dev); 404extern struct device *tty_register_device_attr(struct tty_driver *driver, 405 unsigned index, struct device *device, 406 void *drvdata, 407 const struct attribute_group **attr_grp); 408extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 409extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 410 int buflen); 411extern void tty_write_message(struct tty_struct *tty, char *msg); 412extern int tty_put_char(struct tty_struct *tty, unsigned char c); 413extern int tty_chars_in_buffer(struct tty_struct *tty); 414extern int tty_write_room(struct tty_struct *tty); 415extern void tty_driver_flush_buffer(struct tty_struct *tty); 416extern void tty_throttle(struct tty_struct *tty); 417extern void tty_unthrottle(struct tty_struct *tty); 418extern int tty_throttle_safe(struct tty_struct *tty); 419extern int tty_unthrottle_safe(struct tty_struct *tty); 420extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 421extern void tty_driver_remove_tty(struct tty_driver *driver, 422 struct tty_struct *tty); 423extern void tty_free_termios(struct tty_struct *tty); 424extern int is_current_pgrp_orphaned(void); 425extern int is_ignored(int sig); 426extern int tty_signal(int sig, struct tty_struct *tty); 427extern void tty_hangup(struct tty_struct *tty); 428extern void tty_vhangup(struct tty_struct *tty); 429extern void tty_vhangup_locked(struct tty_struct *tty); 430extern void tty_unhangup(struct file *filp); 431extern int tty_hung_up_p(struct file *filp); 432extern void do_SAK(struct tty_struct *tty); 433extern void __do_SAK(struct tty_struct *tty); 434extern void no_tty(void); 435extern void tty_flush_to_ldisc(struct tty_struct *tty); 436extern void tty_buffer_free_all(struct tty_port *port); 437extern void tty_buffer_flush(struct tty_struct *tty); 438extern void tty_buffer_init(struct tty_port *port); 439extern speed_t tty_termios_baud_rate(struct ktermios *termios); 440extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 441extern void tty_termios_encode_baud_rate(struct ktermios *termios, 442 speed_t ibaud, speed_t obaud); 443extern void tty_encode_baud_rate(struct tty_struct *tty, 444 speed_t ibaud, speed_t obaud); 445 446/** 447 * tty_get_baud_rate - get tty bit rates 448 * @tty: tty to query 449 * 450 * Returns the baud rate as an integer for this terminal. The 451 * termios lock must be held by the caller and the terminal bit 452 * flags may be updated. 453 * 454 * Locking: none 455 */ 456static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 457{ 458 return tty_termios_baud_rate(&tty->termios); 459} 460 461extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 462extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 463extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 464 465extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 466extern void tty_ldisc_deref(struct tty_ldisc *); 467extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 468extern void tty_ldisc_hangup(struct tty_struct *tty); 469extern const struct file_operations tty_ldiscs_proc_fops; 470 471extern void tty_wakeup(struct tty_struct *tty); 472extern void tty_ldisc_flush(struct tty_struct *tty); 473 474extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 475extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 476 unsigned int cmd, unsigned long arg); 477extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 478extern void tty_default_fops(struct file_operations *fops); 479extern struct tty_struct *alloc_tty_struct(void); 480extern int tty_alloc_file(struct file *file); 481extern void tty_add_file(struct tty_struct *tty, struct file *file); 482extern void tty_free_file(struct file *file); 483extern void free_tty_struct(struct tty_struct *tty); 484extern void initialize_tty_struct(struct tty_struct *tty, 485 struct tty_driver *driver, int idx); 486extern void deinitialize_tty_struct(struct tty_struct *tty); 487extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 488extern int tty_release(struct inode *inode, struct file *filp); 489extern int tty_init_termios(struct tty_struct *tty); 490extern int tty_standard_install(struct tty_driver *driver, 491 struct tty_struct *tty); 492 493extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 494extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 495 496extern struct mutex tty_mutex; 497extern spinlock_t tty_files_lock; 498 499extern void tty_write_unlock(struct tty_struct *tty); 500extern int tty_write_lock(struct tty_struct *tty, int ndelay); 501#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 502 503extern void tty_port_init(struct tty_port *port); 504extern void tty_port_link_device(struct tty_port *port, 505 struct tty_driver *driver, unsigned index); 506extern struct device *tty_port_register_device(struct tty_port *port, 507 struct tty_driver *driver, unsigned index, 508 struct device *device); 509extern struct device *tty_port_register_device_attr(struct tty_port *port, 510 struct tty_driver *driver, unsigned index, 511 struct device *device, void *drvdata, 512 const struct attribute_group **attr_grp); 513extern int tty_port_alloc_xmit_buf(struct tty_port *port); 514extern void tty_port_free_xmit_buf(struct tty_port *port); 515extern void tty_port_destroy(struct tty_port *port); 516extern void tty_port_put(struct tty_port *port); 517 518static inline struct tty_port *tty_port_get(struct tty_port *port) 519{ 520 if (port) 521 kref_get(&port->kref); 522 return port; 523} 524 525/* If the cts flow control is enabled, return true. */ 526static inline bool tty_port_cts_enabled(struct tty_port *port) 527{ 528 return port->flags & ASYNC_CTS_FLOW; 529} 530 531extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 532extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 533extern int tty_port_carrier_raised(struct tty_port *port); 534extern void tty_port_raise_dtr_rts(struct tty_port *port); 535extern void tty_port_lower_dtr_rts(struct tty_port *port); 536extern void tty_port_hangup(struct tty_port *port); 537extern void tty_port_tty_wakeup(struct tty_port *port); 538extern int tty_port_block_til_ready(struct tty_port *port, 539 struct tty_struct *tty, struct file *filp); 540extern int tty_port_close_start(struct tty_port *port, 541 struct tty_struct *tty, struct file *filp); 542extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 543extern void tty_port_close(struct tty_port *port, 544 struct tty_struct *tty, struct file *filp); 545extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 546 struct tty_struct *tty); 547extern int tty_port_open(struct tty_port *port, 548 struct tty_struct *tty, struct file *filp); 549static inline int tty_port_users(struct tty_port *port) 550{ 551 return port->count + port->blocked_open; 552} 553 554extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 555extern int tty_unregister_ldisc(int disc); 556extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 557extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 558extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 559extern void tty_ldisc_init(struct tty_struct *tty); 560extern void tty_ldisc_deinit(struct tty_struct *tty); 561extern void tty_ldisc_begin(void); 562/* This last one is just for the tty layer internals and shouldn't be used elsewhere */ 563extern void tty_ldisc_enable(struct tty_struct *tty); 564 565 566/* n_tty.c */ 567extern struct tty_ldisc_ops tty_ldisc_N_TTY; 568extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 569 570/* tty_audit.c */ 571#ifdef CONFIG_AUDIT 572extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 573 size_t size, unsigned icanon); 574extern void tty_audit_exit(void); 575extern void tty_audit_fork(struct signal_struct *sig); 576extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 577extern void tty_audit_push(struct tty_struct *tty); 578extern int tty_audit_push_task(struct task_struct *tsk, 579 kuid_t loginuid, u32 sessionid); 580#else 581static inline void tty_audit_add_data(struct tty_struct *tty, 582 unsigned char *data, size_t size, unsigned icanon) 583{ 584} 585static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 586{ 587} 588static inline void tty_audit_exit(void) 589{ 590} 591static inline void tty_audit_fork(struct signal_struct *sig) 592{ 593} 594static inline void tty_audit_push(struct tty_struct *tty) 595{ 596} 597static inline int tty_audit_push_task(struct task_struct *tsk, 598 kuid_t loginuid, u32 sessionid) 599{ 600 return 0; 601} 602#endif 603 604/* tty_ioctl.c */ 605extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 606 unsigned int cmd, unsigned long arg); 607extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 608 unsigned int cmd, unsigned long arg); 609 610/* serial.c */ 611 612extern void serial_console_init(void); 613 614/* pcxx.c */ 615 616extern int pcxe_open(struct tty_struct *tty, struct file *filp); 617 618/* vt.c */ 619 620extern int vt_ioctl(struct tty_struct *tty, 621 unsigned int cmd, unsigned long arg); 622 623extern long vt_compat_ioctl(struct tty_struct *tty, 624 unsigned int cmd, unsigned long arg); 625 626/* tty_mutex.c */ 627/* functions for preparation of BKL removal */ 628extern void __lockfunc tty_lock(struct tty_struct *tty); 629extern void __lockfunc tty_unlock(struct tty_struct *tty); 630extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 631 struct tty_struct *tty2); 632extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 633 struct tty_struct *tty2); 634 635/* 636 * this shall be called only from where BTM is held (like close) 637 * 638 * We need this to ensure nobody waits for us to finish while we are waiting. 639 * Without this we were encountering system stalls. 640 * 641 * This should be indeed removed with BTM removal later. 642 * 643 * Locking: BTM required. Nobody is allowed to hold port->mutex. 644 */ 645static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 646 long timeout) 647{ 648 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 649 tty_wait_until_sent(tty, timeout); 650 tty_lock(tty); 651} 652 653/* 654 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 655 * 656 * The condition we are waiting for might take a long time to 657 * become true, or might depend on another thread taking the 658 * BTM. In either case, we need to drop the BTM to guarantee 659 * forward progress. This is a leftover from the conversion 660 * from the BKL and should eventually get removed as the BTM 661 * falls out of use. 662 * 663 * Do not use in new code. 664 */ 665#define wait_event_interruptible_tty(tty, wq, condition) \ 666({ \ 667 int __ret = 0; \ 668 if (!(condition)) { \ 669 __wait_event_interruptible_tty(tty, wq, condition, __ret); \ 670 } \ 671 __ret; \ 672}) 673 674#define __wait_event_interruptible_tty(tty, wq, condition, ret) \ 675do { \ 676 DEFINE_WAIT(__wait); \ 677 \ 678 for (;;) { \ 679 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ 680 if (condition) \ 681 break; \ 682 if (!signal_pending(current)) { \ 683 tty_unlock(tty); \ 684 schedule(); \ 685 tty_lock(tty); \ 686 continue; \ 687 } \ 688 ret = -ERESTARTSYS; \ 689 break; \ 690 } \ 691 finish_wait(&wq, &__wait); \ 692} while (0) 693 694 695#endif 696