tty.h revision 4f73bc4dd3e8563ef4109f293a092820dff66d92
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 warned:1; 259 unsigned char ctrl_status; /* ctrl_lock */ 260 unsigned int receive_room; /* Bytes free for queue */ 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#ifdef CONFIG_TTY 322extern void console_init(void); 323extern void tty_kref_put(struct tty_struct *tty); 324extern struct pid *tty_get_pgrp(struct tty_struct *tty); 325extern void tty_vhangup_self(void); 326extern void disassociate_ctty(int priv); 327extern dev_t tty_devnum(struct tty_struct *tty); 328extern void proc_clear_tty(struct task_struct *p); 329extern struct tty_struct *get_current_tty(void); 330/* tty_io.c */ 331extern int __init tty_init(void); 332#else 333static inline void console_init(void) 334{ } 335static inline void tty_kref_put(struct tty_struct *tty) 336{ } 337static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 338{ return NULL; } 339static inline void tty_vhangup_self(void) 340{ } 341static inline void disassociate_ctty(int priv) 342{ } 343static inline dev_t tty_devnum(struct tty_struct *tty) 344{ return 0; } 345static inline void proc_clear_tty(struct task_struct *p) 346{ } 347static inline struct tty_struct *get_current_tty(void) 348{ return NULL; } 349/* tty_io.c */ 350static inline int __init tty_init(void) 351{ return 0; } 352#endif 353 354extern void tty_write_flush(struct tty_struct *); 355 356extern struct ktermios tty_std_termios; 357 358extern int vcs_init(void); 359 360extern struct class *tty_class; 361 362/** 363 * tty_kref_get - get a tty reference 364 * @tty: tty device 365 * 366 * Return a new reference to a tty object. The caller must hold 367 * sufficient locks/counts to ensure that their existing reference cannot 368 * go away 369 */ 370 371static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 372{ 373 if (tty) 374 kref_get(&tty->kref); 375 return tty; 376} 377 378extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 379 const char *routine); 380extern char *tty_name(struct tty_struct *tty, char *buf); 381extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 382extern int tty_check_change(struct tty_struct *tty); 383extern void stop_tty(struct tty_struct *tty); 384extern void start_tty(struct tty_struct *tty); 385extern int tty_register_driver(struct tty_driver *driver); 386extern int tty_unregister_driver(struct tty_driver *driver); 387extern struct device *tty_register_device(struct tty_driver *driver, 388 unsigned index, struct device *dev); 389extern struct device *tty_register_device_attr(struct tty_driver *driver, 390 unsigned index, struct device *device, 391 void *drvdata, 392 const struct attribute_group **attr_grp); 393extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 394extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 395 int buflen); 396extern void tty_write_message(struct tty_struct *tty, char *msg); 397extern int tty_put_char(struct tty_struct *tty, unsigned char c); 398extern int tty_chars_in_buffer(struct tty_struct *tty); 399extern int tty_write_room(struct tty_struct *tty); 400extern void tty_driver_flush_buffer(struct tty_struct *tty); 401extern void tty_throttle(struct tty_struct *tty); 402extern void tty_unthrottle(struct tty_struct *tty); 403extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 404extern void tty_driver_remove_tty(struct tty_driver *driver, 405 struct tty_struct *tty); 406extern void tty_free_termios(struct tty_struct *tty); 407extern int is_current_pgrp_orphaned(void); 408extern int is_ignored(int sig); 409extern int tty_signal(int sig, struct tty_struct *tty); 410extern void tty_hangup(struct tty_struct *tty); 411extern void tty_vhangup(struct tty_struct *tty); 412extern void tty_vhangup_locked(struct tty_struct *tty); 413extern void tty_unhangup(struct file *filp); 414extern int tty_hung_up_p(struct file *filp); 415extern void do_SAK(struct tty_struct *tty); 416extern void __do_SAK(struct tty_struct *tty); 417extern void no_tty(void); 418extern void tty_flush_to_ldisc(struct tty_struct *tty); 419extern void tty_buffer_free_all(struct tty_port *port); 420extern void tty_buffer_flush(struct tty_struct *tty); 421extern void tty_buffer_init(struct tty_port *port); 422extern speed_t tty_get_baud_rate(struct tty_struct *tty); 423extern speed_t tty_termios_baud_rate(struct ktermios *termios); 424extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 425extern void tty_termios_encode_baud_rate(struct ktermios *termios, 426 speed_t ibaud, speed_t obaud); 427extern void tty_encode_baud_rate(struct tty_struct *tty, 428 speed_t ibaud, speed_t obaud); 429extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 430extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 431extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 432 433extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 434extern void tty_ldisc_deref(struct tty_ldisc *); 435extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 436extern void tty_ldisc_hangup(struct tty_struct *tty); 437extern const struct file_operations tty_ldiscs_proc_fops; 438 439extern void tty_wakeup(struct tty_struct *tty); 440extern void tty_ldisc_flush(struct tty_struct *tty); 441 442extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 443extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 444 unsigned int cmd, unsigned long arg); 445extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 446extern void tty_default_fops(struct file_operations *fops); 447extern struct tty_struct *alloc_tty_struct(void); 448extern int tty_alloc_file(struct file *file); 449extern void tty_add_file(struct tty_struct *tty, struct file *file); 450extern void tty_free_file(struct file *file); 451extern void free_tty_struct(struct tty_struct *tty); 452extern void initialize_tty_struct(struct tty_struct *tty, 453 struct tty_driver *driver, int idx); 454extern void deinitialize_tty_struct(struct tty_struct *tty); 455extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 456extern int tty_release(struct inode *inode, struct file *filp); 457extern int tty_init_termios(struct tty_struct *tty); 458extern int tty_standard_install(struct tty_driver *driver, 459 struct tty_struct *tty); 460 461extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 462extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 463 464extern struct mutex tty_mutex; 465extern spinlock_t tty_files_lock; 466 467extern void tty_write_unlock(struct tty_struct *tty); 468extern int tty_write_lock(struct tty_struct *tty, int ndelay); 469#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 470 471extern void tty_port_init(struct tty_port *port); 472extern void tty_port_link_device(struct tty_port *port, 473 struct tty_driver *driver, unsigned index); 474extern struct device *tty_port_register_device(struct tty_port *port, 475 struct tty_driver *driver, unsigned index, 476 struct device *device); 477extern struct device *tty_port_register_device_attr(struct tty_port *port, 478 struct tty_driver *driver, unsigned index, 479 struct device *device, void *drvdata, 480 const struct attribute_group **attr_grp); 481extern int tty_port_alloc_xmit_buf(struct tty_port *port); 482extern void tty_port_free_xmit_buf(struct tty_port *port); 483extern void tty_port_destroy(struct tty_port *port); 484extern void tty_port_put(struct tty_port *port); 485 486static inline struct tty_port *tty_port_get(struct tty_port *port) 487{ 488 if (port) 489 kref_get(&port->kref); 490 return port; 491} 492 493/* If the cts flow control is enabled, return true. */ 494static inline bool tty_port_cts_enabled(struct tty_port *port) 495{ 496 return port->flags & ASYNC_CTS_FLOW; 497} 498 499extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 500extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 501extern int tty_port_carrier_raised(struct tty_port *port); 502extern void tty_port_raise_dtr_rts(struct tty_port *port); 503extern void tty_port_lower_dtr_rts(struct tty_port *port); 504extern void tty_port_hangup(struct tty_port *port); 505extern int tty_port_block_til_ready(struct tty_port *port, 506 struct tty_struct *tty, struct file *filp); 507extern int tty_port_close_start(struct tty_port *port, 508 struct tty_struct *tty, struct file *filp); 509extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 510extern void tty_port_close(struct tty_port *port, 511 struct tty_struct *tty, struct file *filp); 512extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 513 struct tty_struct *tty); 514extern int tty_port_open(struct tty_port *port, 515 struct tty_struct *tty, struct file *filp); 516static inline int tty_port_users(struct tty_port *port) 517{ 518 return port->count + port->blocked_open; 519} 520 521extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 522extern int tty_unregister_ldisc(int disc); 523extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 524extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 525extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 526extern void tty_ldisc_init(struct tty_struct *tty); 527extern void tty_ldisc_deinit(struct tty_struct *tty); 528extern void tty_ldisc_begin(void); 529/* This last one is just for the tty layer internals and shouldn't be used elsewhere */ 530extern void tty_ldisc_enable(struct tty_struct *tty); 531 532 533/* n_tty.c */ 534extern struct tty_ldisc_ops tty_ldisc_N_TTY; 535extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 536 537/* tty_audit.c */ 538#ifdef CONFIG_AUDIT 539extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 540 size_t size, unsigned icanon); 541extern void tty_audit_exit(void); 542extern void tty_audit_fork(struct signal_struct *sig); 543extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 544extern void tty_audit_push(struct tty_struct *tty); 545extern int tty_audit_push_task(struct task_struct *tsk, 546 kuid_t loginuid, u32 sessionid); 547#else 548static inline void tty_audit_add_data(struct tty_struct *tty, 549 unsigned char *data, size_t size, unsigned icanon) 550{ 551} 552static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 553{ 554} 555static inline void tty_audit_exit(void) 556{ 557} 558static inline void tty_audit_fork(struct signal_struct *sig) 559{ 560} 561static inline void tty_audit_push(struct tty_struct *tty) 562{ 563} 564static inline int tty_audit_push_task(struct task_struct *tsk, 565 kuid_t loginuid, u32 sessionid) 566{ 567 return 0; 568} 569#endif 570 571/* tty_ioctl.c */ 572extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 573 unsigned int cmd, unsigned long arg); 574extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 575 unsigned int cmd, unsigned long arg); 576 577/* serial.c */ 578 579extern void serial_console_init(void); 580 581/* pcxx.c */ 582 583extern int pcxe_open(struct tty_struct *tty, struct file *filp); 584 585/* vt.c */ 586 587extern int vt_ioctl(struct tty_struct *tty, 588 unsigned int cmd, unsigned long arg); 589 590extern long vt_compat_ioctl(struct tty_struct *tty, 591 unsigned int cmd, unsigned long arg); 592 593/* tty_mutex.c */ 594/* functions for preparation of BKL removal */ 595extern void __lockfunc tty_lock(struct tty_struct *tty); 596extern void __lockfunc tty_unlock(struct tty_struct *tty); 597extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 598 struct tty_struct *tty2); 599extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 600 struct tty_struct *tty2); 601 602/* 603 * this shall be called only from where BTM is held (like close) 604 * 605 * We need this to ensure nobody waits for us to finish while we are waiting. 606 * Without this we were encountering system stalls. 607 * 608 * This should be indeed removed with BTM removal later. 609 * 610 * Locking: BTM required. Nobody is allowed to hold port->mutex. 611 */ 612static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 613 long timeout) 614{ 615 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 616 tty_wait_until_sent(tty, timeout); 617 tty_lock(tty); 618} 619 620/* 621 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 622 * 623 * The condition we are waiting for might take a long time to 624 * become true, or might depend on another thread taking the 625 * BTM. In either case, we need to drop the BTM to guarantee 626 * forward progress. This is a leftover from the conversion 627 * from the BKL and should eventually get removed as the BTM 628 * falls out of use. 629 * 630 * Do not use in new code. 631 */ 632#define wait_event_interruptible_tty(tty, wq, condition) \ 633({ \ 634 int __ret = 0; \ 635 if (!(condition)) { \ 636 __wait_event_interruptible_tty(tty, wq, condition, __ret); \ 637 } \ 638 __ret; \ 639}) 640 641#define __wait_event_interruptible_tty(tty, wq, condition, ret) \ 642do { \ 643 DEFINE_WAIT(__wait); \ 644 \ 645 for (;;) { \ 646 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ 647 if (condition) \ 648 break; \ 649 if (!signal_pending(current)) { \ 650 tty_unlock(tty); \ 651 schedule(); \ 652 tty_lock(tty); \ 653 continue; \ 654 } \ 655 ret = -ERESTARTSYS; \ 656 break; \ 657 } \ 658 finish_wait(&wq, &__wait); \ 659} while (0) 660 661 662#endif 663