1 #ifndef _LINUX_TTY_H 2 #define _LINUX_TTY_H 3 4 #include <linux/fs.h> 5 #include <linux/major.h> 6 #include <linux/termios.h> 7 #include <linux/workqueue.h> 8 #include <linux/tty_driver.h> 9 #include <linux/tty_ldisc.h> 10 #include <linux/mutex.h> 11 #include <linux/tty_flags.h> 12 #include <uapi/linux/tty.h> 13 #include <linux/rwsem.h> 14 #include <linux/llist.h> 15 16 17 18 /* 19 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 20 * hardcoded at present.) 21 */ 22 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 23 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 24 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 25 26 /* 27 * This character is the same as _POSIX_VDISABLE: it cannot be used as 28 * a c_cc[] character, but indicates that a particular special character 29 * isn't in use (eg VINTR has no character etc) 30 */ 31 #define __DISABLED_CHAR '\0' 32 33 struct tty_buffer { 34 union { 35 struct tty_buffer *next; 36 struct llist_node free; 37 }; 38 int used; 39 int size; 40 int commit; 41 int read; 42 /* Data points here */ 43 unsigned long data[0]; 44 }; 45 46 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 47 { 48 return ((unsigned char *)b->data) + ofs; 49 } 50 51 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 52 { 53 return (char *)char_buf_ptr(b, ofs) + b->size; 54 } 55 56 struct tty_bufhead { 57 struct tty_buffer *head; /* Queue head */ 58 struct work_struct work; 59 struct mutex lock; 60 atomic_t priority; 61 struct tty_buffer sentinel; 62 struct llist_head free; /* Free queue head */ 63 atomic_t memory_used; /* In-use buffers excluding free list */ 64 struct tty_buffer *tail; /* Active buffer */ 65 }; 66 /* 67 * When a break, frame error, or parity error happens, these codes are 68 * stuffed into the flags buffer. 69 */ 70 #define TTY_NORMAL 0 71 #define TTY_BREAK 1 72 #define TTY_FRAME 2 73 #define TTY_PARITY 3 74 #define TTY_OVERRUN 4 75 76 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 77 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 78 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 79 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 80 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 81 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 82 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 83 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 84 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 85 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 86 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 87 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 88 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 89 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 90 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 91 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 92 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 93 94 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 95 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 96 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 97 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 98 99 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 100 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 101 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 102 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 103 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 104 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 105 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 106 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 107 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 108 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 109 #define I_IXON(tty) _I_FLAG((tty), IXON) 110 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 111 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 112 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 113 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 114 115 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 116 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 117 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 118 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 119 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 120 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 121 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 122 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 123 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 124 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 125 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 126 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 127 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 128 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 129 130 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 131 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 132 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 133 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 134 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 135 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 136 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 137 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 138 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 139 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 140 141 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 142 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 143 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 144 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 145 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 146 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 147 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 148 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 149 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 150 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 151 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 152 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 153 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 154 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 155 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 156 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 157 158 struct device; 159 struct signal_struct; 160 161 /* 162 * Port level information. Each device keeps its own port level information 163 * so provide a common structure for those ports wanting to use common support 164 * routines. 165 * 166 * The tty port has a different lifetime to the tty so must be kept apart. 167 * In addition be careful as tty -> port mappings are valid for the life 168 * of the tty object but in many cases port -> tty mappings are valid only 169 * until a hangup so don't use the wrong path. 170 */ 171 172 struct tty_port; 173 174 struct tty_port_operations { 175 /* Return 1 if the carrier is raised */ 176 int (*carrier_raised)(struct tty_port *port); 177 /* Control the DTR line */ 178 void (*dtr_rts)(struct tty_port *port, int raise); 179 /* Called when the last close completes or a hangup finishes 180 IFF the port was initialized. Do not use to free resources. Called 181 under the port mutex to serialize against activate/shutdowns */ 182 void (*shutdown)(struct tty_port *port); 183 /* Called under the port mutex from tty_port_open, serialized using 184 the port mutex */ 185 /* FIXME: long term getting the tty argument *out* of this would be 186 good for consoles */ 187 int (*activate)(struct tty_port *port, struct tty_struct *tty); 188 /* Called on the final put of a port */ 189 void (*destruct)(struct tty_port *port); 190 }; 191 192 struct tty_port { 193 struct tty_bufhead buf; /* Locked internally */ 194 struct tty_struct *tty; /* Back pointer */ 195 struct tty_struct *itty; /* internal back ptr */ 196 const struct tty_port_operations *ops; /* Port operations */ 197 spinlock_t lock; /* Lock protecting tty field */ 198 int blocked_open; /* Waiting to open */ 199 int count; /* Usage count */ 200 wait_queue_head_t open_wait; /* Open waiters */ 201 wait_queue_head_t close_wait; /* Close waiters */ 202 wait_queue_head_t delta_msr_wait; /* Modem status change */ 203 unsigned long flags; /* TTY flags ASY_*/ 204 unsigned char console:1, /* port is a console */ 205 low_latency:1; /* direct buffer flush */ 206 struct mutex mutex; /* Locking */ 207 struct mutex buf_mutex; /* Buffer alloc lock */ 208 unsigned char *xmit_buf; /* Optional buffer */ 209 unsigned int close_delay; /* Close port delay */ 210 unsigned int closing_wait; /* Delay for output */ 211 int drain_delay; /* Set to zero if no pure time 212 based drain is needed else 213 set to size of fifo */ 214 struct kref kref; /* Ref counter */ 215 }; 216 217 /* 218 * Where all of the state associated with a tty is kept while the tty 219 * is open. Since the termios state should be kept even if the tty 220 * has been closed --- for things like the baud rate, etc --- it is 221 * not stored here, but rather a pointer to the real state is stored 222 * here. Possible the winsize structure should have the same 223 * treatment, but (1) the default 80x24 is usually right and (2) it's 224 * most often used by a windowing system, which will set the correct 225 * size each time the window is created or resized anyway. 226 * - TYT, 9/14/92 227 */ 228 229 struct tty_operations; 230 231 struct tty_struct { 232 int magic; 233 struct kref kref; 234 struct device *dev; 235 struct tty_driver *driver; 236 const struct tty_operations *ops; 237 int index; 238 239 /* Protects ldisc changes: Lock tty not pty */ 240 struct ld_semaphore ldisc_sem; 241 struct tty_ldisc *ldisc; 242 243 struct mutex atomic_write_lock; 244 struct mutex legacy_mutex; 245 struct mutex throttle_mutex; 246 struct rw_semaphore termios_rwsem; 247 struct mutex winsize_mutex; 248 spinlock_t ctrl_lock; 249 /* Termios values are protected by the termios rwsem */ 250 struct ktermios termios, termios_locked; 251 struct termiox *termiox; /* May be NULL for unsupported */ 252 char name[64]; 253 struct pid *pgrp; /* Protected by ctrl lock */ 254 struct pid *session; 255 unsigned long flags; 256 int count; 257 struct winsize winsize; /* winsize_mutex */ 258 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; 259 unsigned char ctrl_status; /* ctrl_lock */ 260 unsigned int receive_room; /* Bytes free for queue */ 261 int flow_change; 262 263 struct tty_struct *link; 264 struct fasync_struct *fasync; 265 int alt_speed; /* For magic substitution of 38400 bps */ 266 wait_queue_head_t write_wait; 267 wait_queue_head_t read_wait; 268 struct work_struct hangup_work; 269 void *disc_data; 270 void *driver_data; 271 struct list_head tty_files; 272 273 #define N_TTY_BUF_SIZE 4096 274 275 unsigned char closing:1; 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 */ 284 struct 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_CLOSING 7 /* ->close() in progress */ 308 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 309 #define TTY_PTY_LOCK 16 /* pty private */ 310 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 311 #define TTY_HUPPED 18 /* Post driver->hangup() */ 312 #define TTY_HUPPING 21 /* ->hangup() in progress */ 313 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 314 315 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 316 317 /* Values for tty->flow_change */ 318 #define TTY_THROTTLE_SAFE 1 319 #define TTY_UNTHROTTLE_SAFE 2 320 321 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 322 { 323 tty->flow_change = val; 324 } 325 326 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 327 { 328 tty->flow_change = val; 329 smp_mb(); 330 } 331 332 #ifdef CONFIG_TTY 333 extern void console_init(void); 334 extern void tty_kref_put(struct tty_struct *tty); 335 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 336 extern void tty_vhangup_self(void); 337 extern void disassociate_ctty(int priv); 338 extern dev_t tty_devnum(struct tty_struct *tty); 339 extern void proc_clear_tty(struct task_struct *p); 340 extern struct tty_struct *get_current_tty(void); 341 /* tty_io.c */ 342 extern int __init tty_init(void); 343 #else 344 static inline void console_init(void) 345 { } 346 static inline void tty_kref_put(struct tty_struct *tty) 347 { } 348 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 349 { return NULL; } 350 static inline void tty_vhangup_self(void) 351 { } 352 static inline void disassociate_ctty(int priv) 353 { } 354 static inline dev_t tty_devnum(struct tty_struct *tty) 355 { return 0; } 356 static inline void proc_clear_tty(struct task_struct *p) 357 { } 358 static inline struct tty_struct *get_current_tty(void) 359 { return NULL; } 360 /* tty_io.c */ 361 static inline int __init tty_init(void) 362 { return 0; } 363 #endif 364 365 extern void tty_write_flush(struct tty_struct *); 366 367 extern struct ktermios tty_std_termios; 368 369 extern int vcs_init(void); 370 371 extern 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 */ 381 382 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 383 { 384 if (tty) 385 kref_get(&tty->kref); 386 return tty; 387 } 388 389 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 390 const char *routine); 391 extern char *tty_name(struct tty_struct *tty, char *buf); 392 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 393 extern int tty_check_change(struct tty_struct *tty); 394 extern void stop_tty(struct tty_struct *tty); 395 extern void start_tty(struct tty_struct *tty); 396 extern int tty_register_driver(struct tty_driver *driver); 397 extern int tty_unregister_driver(struct tty_driver *driver); 398 extern struct device *tty_register_device(struct tty_driver *driver, 399 unsigned index, struct device *dev); 400 extern struct device *tty_register_device_attr(struct tty_driver *driver, 401 unsigned index, struct device *device, 402 void *drvdata, 403 const struct attribute_group **attr_grp); 404 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 405 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 406 int buflen); 407 extern void tty_write_message(struct tty_struct *tty, char *msg); 408 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 409 extern int tty_chars_in_buffer(struct tty_struct *tty); 410 extern int tty_write_room(struct tty_struct *tty); 411 extern void tty_driver_flush_buffer(struct tty_struct *tty); 412 extern void tty_throttle(struct tty_struct *tty); 413 extern void tty_unthrottle(struct tty_struct *tty); 414 extern int tty_throttle_safe(struct tty_struct *tty); 415 extern int tty_unthrottle_safe(struct tty_struct *tty); 416 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 417 extern void tty_driver_remove_tty(struct tty_driver *driver, 418 struct tty_struct *tty); 419 extern void tty_free_termios(struct tty_struct *tty); 420 extern int is_current_pgrp_orphaned(void); 421 extern int is_ignored(int sig); 422 extern int tty_signal(int sig, struct tty_struct *tty); 423 extern void tty_hangup(struct tty_struct *tty); 424 extern void tty_vhangup(struct tty_struct *tty); 425 extern void tty_vhangup_locked(struct tty_struct *tty); 426 extern void tty_unhangup(struct file *filp); 427 extern int tty_hung_up_p(struct file *filp); 428 extern void do_SAK(struct tty_struct *tty); 429 extern void __do_SAK(struct tty_struct *tty); 430 extern void no_tty(void); 431 extern void tty_flush_to_ldisc(struct tty_struct *tty); 432 extern void tty_buffer_free_all(struct tty_port *port); 433 extern void tty_buffer_flush(struct tty_struct *tty); 434 extern void tty_buffer_init(struct tty_port *port); 435 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 436 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 437 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 438 speed_t ibaud, speed_t obaud); 439 extern void tty_encode_baud_rate(struct tty_struct *tty, 440 speed_t ibaud, speed_t obaud); 441 442 /** 443 * tty_get_baud_rate - get tty bit rates 444 * @tty: tty to query 445 * 446 * Returns the baud rate as an integer for this terminal. The 447 * termios lock must be held by the caller and the terminal bit 448 * flags may be updated. 449 * 450 * Locking: none 451 */ 452 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 453 { 454 return tty_termios_baud_rate(&tty->termios); 455 } 456 457 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 458 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 459 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 460 461 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 462 extern void tty_ldisc_deref(struct tty_ldisc *); 463 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 464 extern void tty_ldisc_hangup(struct tty_struct *tty); 465 extern const struct file_operations tty_ldiscs_proc_fops; 466 467 extern void tty_wakeup(struct tty_struct *tty); 468 extern void tty_ldisc_flush(struct tty_struct *tty); 469 470 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 471 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 472 unsigned int cmd, unsigned long arg); 473 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 474 extern void tty_default_fops(struct file_operations *fops); 475 extern struct tty_struct *alloc_tty_struct(void); 476 extern int tty_alloc_file(struct file *file); 477 extern void tty_add_file(struct tty_struct *tty, struct file *file); 478 extern void tty_free_file(struct file *file); 479 extern void free_tty_struct(struct tty_struct *tty); 480 extern void initialize_tty_struct(struct tty_struct *tty, 481 struct tty_driver *driver, int idx); 482 extern void deinitialize_tty_struct(struct tty_struct *tty); 483 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 484 extern int tty_release(struct inode *inode, struct file *filp); 485 extern int tty_init_termios(struct tty_struct *tty); 486 extern int tty_standard_install(struct tty_driver *driver, 487 struct tty_struct *tty); 488 489 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 490 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 491 492 extern struct mutex tty_mutex; 493 extern spinlock_t tty_files_lock; 494 495 extern void tty_write_unlock(struct tty_struct *tty); 496 extern int tty_write_lock(struct tty_struct *tty, int ndelay); 497 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 498 499 extern void tty_port_init(struct tty_port *port); 500 extern void tty_port_link_device(struct tty_port *port, 501 struct tty_driver *driver, unsigned index); 502 extern struct device *tty_port_register_device(struct tty_port *port, 503 struct tty_driver *driver, unsigned index, 504 struct device *device); 505 extern struct device *tty_port_register_device_attr(struct tty_port *port, 506 struct tty_driver *driver, unsigned index, 507 struct device *device, void *drvdata, 508 const struct attribute_group **attr_grp); 509 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 510 extern void tty_port_free_xmit_buf(struct tty_port *port); 511 extern void tty_port_destroy(struct tty_port *port); 512 extern void tty_port_put(struct tty_port *port); 513 514 static inline struct tty_port *tty_port_get(struct tty_port *port) 515 { 516 if (port) 517 kref_get(&port->kref); 518 return port; 519 } 520 521 /* If the cts flow control is enabled, return true. */ 522 static inline bool tty_port_cts_enabled(struct tty_port *port) 523 { 524 return port->flags & ASYNC_CTS_FLOW; 525 } 526 527 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 528 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 529 extern int tty_port_carrier_raised(struct tty_port *port); 530 extern void tty_port_raise_dtr_rts(struct tty_port *port); 531 extern void tty_port_lower_dtr_rts(struct tty_port *port); 532 extern void tty_port_hangup(struct tty_port *port); 533 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 534 extern void tty_port_tty_wakeup(struct tty_port *port); 535 extern int tty_port_block_til_ready(struct tty_port *port, 536 struct tty_struct *tty, struct file *filp); 537 extern int tty_port_close_start(struct tty_port *port, 538 struct tty_struct *tty, struct file *filp); 539 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 540 extern void tty_port_close(struct tty_port *port, 541 struct tty_struct *tty, struct file *filp); 542 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 543 struct tty_struct *tty); 544 extern int tty_port_open(struct tty_port *port, 545 struct tty_struct *tty, struct file *filp); 546 static inline int tty_port_users(struct tty_port *port) 547 { 548 return port->count + port->blocked_open; 549 } 550 551 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 552 extern int tty_unregister_ldisc(int disc); 553 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 554 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 555 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 556 extern void tty_ldisc_init(struct tty_struct *tty); 557 extern void tty_ldisc_deinit(struct tty_struct *tty); 558 extern void tty_ldisc_begin(void); 559 560 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 561 char *f, int count) 562 { 563 if (ld->ops->receive_buf2) 564 count = ld->ops->receive_buf2(ld->tty, p, f, count); 565 else { 566 count = min_t(int, count, ld->tty->receive_room); 567 if (count) 568 ld->ops->receive_buf(ld->tty, p, f, count); 569 } 570 return count; 571 } 572 573 574 /* n_tty.c */ 575 extern struct tty_ldisc_ops tty_ldisc_N_TTY; 576 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 577 578 /* tty_audit.c */ 579 #ifdef CONFIG_AUDIT 580 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 581 size_t size, unsigned icanon); 582 extern void tty_audit_exit(void); 583 extern void tty_audit_fork(struct signal_struct *sig); 584 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 585 extern void tty_audit_push(struct tty_struct *tty); 586 extern int tty_audit_push_current(void); 587 #else 588 static inline void tty_audit_add_data(struct tty_struct *tty, 589 unsigned char *data, size_t size, unsigned icanon) 590 { 591 } 592 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 593 { 594 } 595 static inline void tty_audit_exit(void) 596 { 597 } 598 static inline void tty_audit_fork(struct signal_struct *sig) 599 { 600 } 601 static inline void tty_audit_push(struct tty_struct *tty) 602 { 603 } 604 static inline int tty_audit_push_current(void) 605 { 606 return 0; 607 } 608 #endif 609 610 /* tty_ioctl.c */ 611 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 612 unsigned int cmd, unsigned long arg); 613 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 614 unsigned int cmd, unsigned long arg); 615 616 /* serial.c */ 617 618 extern void serial_console_init(void); 619 620 /* pcxx.c */ 621 622 extern int pcxe_open(struct tty_struct *tty, struct file *filp); 623 624 /* vt.c */ 625 626 extern int vt_ioctl(struct tty_struct *tty, 627 unsigned int cmd, unsigned long arg); 628 629 extern long vt_compat_ioctl(struct tty_struct *tty, 630 unsigned int cmd, unsigned long arg); 631 632 /* tty_mutex.c */ 633 /* functions for preparation of BKL removal */ 634 extern void __lockfunc tty_lock(struct tty_struct *tty); 635 extern void __lockfunc tty_unlock(struct tty_struct *tty); 636 extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 637 struct tty_struct *tty2); 638 extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 639 struct tty_struct *tty2); 640 641 /* 642 * this shall be called only from where BTM is held (like close) 643 * 644 * We need this to ensure nobody waits for us to finish while we are waiting. 645 * Without this we were encountering system stalls. 646 * 647 * This should be indeed removed with BTM removal later. 648 * 649 * Locking: BTM required. Nobody is allowed to hold port->mutex. 650 */ 651 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 652 long timeout) 653 { 654 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 655 tty_wait_until_sent(tty, timeout); 656 tty_lock(tty); 657 } 658 659 /* 660 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 661 * 662 * The condition we are waiting for might take a long time to 663 * become true, or might depend on another thread taking the 664 * BTM. In either case, we need to drop the BTM to guarantee 665 * forward progress. This is a leftover from the conversion 666 * from the BKL and should eventually get removed as the BTM 667 * falls out of use. 668 * 669 * Do not use in new code. 670 */ 671 #define wait_event_interruptible_tty(tty, wq, condition) \ 672 ({ \ 673 int __ret = 0; \ 674 if (!(condition)) \ 675 __ret = __wait_event_interruptible_tty(tty, wq, \ 676 condition); \ 677 __ret; \ 678 }) 679 680 #define __wait_event_interruptible_tty(tty, wq, condition) \ 681 ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ 682 tty_unlock(tty); \ 683 schedule(); \ 684 tty_lock(tty)) 685 686 #ifdef CONFIG_PROC_FS 687 extern void proc_tty_register_driver(struct tty_driver *); 688 extern void proc_tty_unregister_driver(struct tty_driver *); 689 #else 690 static inline void proc_tty_register_driver(struct tty_driver *d) {} 691 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 692 #endif 693 694 #endif 695