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 void (*drop)(struct tty_port *port); 184 /* Called under the port mutex from tty_port_open, serialized using 185 the port mutex */ 186 /* FIXME: long term getting the tty argument *out* of this would be 187 good for consoles */ 188 int (*activate)(struct tty_port *port, struct tty_struct *tty); 189 /* Called on the final put of a port */ 190 void (*destruct)(struct tty_port *port); 191 }; 192 193 struct tty_port { 194 struct tty_bufhead buf; /* Locked internally */ 195 struct tty_struct *tty; /* Back pointer */ 196 struct tty_struct *itty; /* internal back ptr */ 197 const struct tty_port_operations *ops; /* Port operations */ 198 spinlock_t lock; /* Lock protecting tty field */ 199 int blocked_open; /* Waiting to open */ 200 int count; /* Usage count */ 201 wait_queue_head_t open_wait; /* Open waiters */ 202 wait_queue_head_t close_wait; /* Close waiters */ 203 wait_queue_head_t delta_msr_wait; /* Modem status change */ 204 unsigned long flags; /* TTY flags ASY_*/ 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 */ 229 230 struct tty_operations; 231 232 struct 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 ld_semaphore ldisc_sem; 242 struct tty_ldisc *ldisc; 243 244 struct mutex atomic_write_lock; 245 struct mutex legacy_mutex; 246 struct mutex throttle_mutex; 247 struct rw_semaphore termios_rwsem; 248 struct mutex winsize_mutex; 249 spinlock_t ctrl_lock; 250 /* Termios values are protected by the termios rwsem */ 251 struct ktermios termios, termios_locked; 252 struct termiox *termiox; /* May be NULL for unsupported */ 253 char name[64]; 254 struct pid *pgrp; /* Protected by ctrl lock */ 255 struct pid *session; 256 unsigned long flags; 257 int count; 258 struct winsize winsize; /* winsize_mutex */ 259 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; 260 unsigned char ctrl_status; /* ctrl_lock */ 261 unsigned int receive_room; /* Bytes free for queue */ 262 int flow_change; 263 264 struct tty_struct *link; 265 struct fasync_struct *fasync; 266 int alt_speed; /* For magic substitution of 38400 bps */ 267 wait_queue_head_t write_wait; 268 wait_queue_head_t read_wait; 269 struct work_struct hangup_work; 270 void *disc_data; 271 void *driver_data; 272 struct list_head tty_files; 273 274 #define N_TTY_BUF_SIZE 4096 275 276 unsigned char closing:1; 277 unsigned char *write_buf; 278 int write_cnt; 279 /* If the tty has a pending do_SAK, queue it here - akpm */ 280 struct work_struct SAK_work; 281 struct tty_port *port; 282 }; 283 284 /* Each of a tty's open files has private_data pointing to tty_file_private */ 285 struct tty_file_private { 286 struct tty_struct *tty; 287 struct file *file; 288 struct list_head list; 289 }; 290 291 /* tty magic number */ 292 #define TTY_MAGIC 0x5401 293 294 /* 295 * These bits are used in the flags field of the tty structure. 296 * 297 * So that interrupts won't be able to mess up the queues, 298 * copy_to_cooked must be atomic with respect to itself, as must 299 * tty->write. Thus, you must use the inline functions set_bit() and 300 * clear_bit() to make things atomic. 301 */ 302 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 303 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 304 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 305 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 306 #define TTY_DEBUG 4 /* Debugging */ 307 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 308 #define TTY_CLOSING 7 /* ->close() in progress */ 309 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 310 #define TTY_PTY_LOCK 16 /* pty private */ 311 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 312 #define TTY_HUPPED 18 /* Post driver->hangup() */ 313 #define TTY_HUPPING 21 /* ->hangup() in progress */ 314 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 315 316 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 317 318 /* Values for tty->flow_change */ 319 #define TTY_THROTTLE_SAFE 1 320 #define TTY_UNTHROTTLE_SAFE 2 321 322 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 323 { 324 tty->flow_change = val; 325 } 326 327 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 328 { 329 tty->flow_change = val; 330 smp_mb(); 331 } 332 333 #ifdef CONFIG_TTY 334 extern void console_init(void); 335 extern void tty_kref_put(struct tty_struct *tty); 336 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 337 extern void tty_vhangup_self(void); 338 extern void disassociate_ctty(int priv); 339 extern dev_t tty_devnum(struct tty_struct *tty); 340 extern void proc_clear_tty(struct task_struct *p); 341 extern struct tty_struct *get_current_tty(void); 342 /* tty_io.c */ 343 extern int __init tty_init(void); 344 #else 345 static inline void console_init(void) 346 { } 347 static inline void tty_kref_put(struct tty_struct *tty) 348 { } 349 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 350 { return NULL; } 351 static inline void tty_vhangup_self(void) 352 { } 353 static inline void disassociate_ctty(int priv) 354 { } 355 static inline dev_t tty_devnum(struct tty_struct *tty) 356 { return 0; } 357 static inline void proc_clear_tty(struct task_struct *p) 358 { } 359 static inline struct tty_struct *get_current_tty(void) 360 { return NULL; } 361 /* tty_io.c */ 362 static inline int __init tty_init(void) 363 { return 0; } 364 #endif 365 366 extern void tty_write_flush(struct tty_struct *); 367 368 extern struct ktermios tty_std_termios; 369 370 extern int vcs_init(void); 371 372 extern struct class *tty_class; 373 374 /** 375 * tty_kref_get - get a tty reference 376 * @tty: tty device 377 * 378 * Return a new reference to a tty object. The caller must hold 379 * sufficient locks/counts to ensure that their existing reference cannot 380 * go away 381 */ 382 383 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 384 { 385 if (tty) 386 kref_get(&tty->kref); 387 return tty; 388 } 389 390 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 391 const char *routine); 392 extern char *tty_name(struct tty_struct *tty, char *buf); 393 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 394 extern int tty_check_change(struct tty_struct *tty); 395 extern void stop_tty(struct tty_struct *tty); 396 extern void start_tty(struct tty_struct *tty); 397 extern int tty_register_driver(struct tty_driver *driver); 398 extern int tty_unregister_driver(struct tty_driver *driver); 399 extern struct device *tty_register_device(struct tty_driver *driver, 400 unsigned index, struct device *dev); 401 extern struct device *tty_register_device_attr(struct tty_driver *driver, 402 unsigned index, struct device *device, 403 void *drvdata, 404 const struct attribute_group **attr_grp); 405 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 406 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 407 int buflen); 408 extern void tty_write_message(struct tty_struct *tty, char *msg); 409 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 410 extern int tty_chars_in_buffer(struct tty_struct *tty); 411 extern int tty_write_room(struct tty_struct *tty); 412 extern void tty_driver_flush_buffer(struct tty_struct *tty); 413 extern void tty_throttle(struct tty_struct *tty); 414 extern void tty_unthrottle(struct tty_struct *tty); 415 extern int tty_throttle_safe(struct tty_struct *tty); 416 extern int tty_unthrottle_safe(struct tty_struct *tty); 417 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 418 extern void tty_driver_remove_tty(struct tty_driver *driver, 419 struct tty_struct *tty); 420 extern void tty_free_termios(struct tty_struct *tty); 421 extern int is_current_pgrp_orphaned(void); 422 extern int is_ignored(int sig); 423 extern int tty_signal(int sig, struct tty_struct *tty); 424 extern void tty_hangup(struct tty_struct *tty); 425 extern void tty_vhangup(struct tty_struct *tty); 426 extern void tty_vhangup_locked(struct tty_struct *tty); 427 extern void tty_unhangup(struct file *filp); 428 extern int tty_hung_up_p(struct file *filp); 429 extern void do_SAK(struct tty_struct *tty); 430 extern void __do_SAK(struct tty_struct *tty); 431 extern void no_tty(void); 432 extern void tty_flush_to_ldisc(struct tty_struct *tty); 433 extern void tty_buffer_free_all(struct tty_port *port); 434 extern void tty_buffer_flush(struct tty_struct *tty); 435 extern void tty_buffer_init(struct tty_port *port); 436 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 437 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 438 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 439 speed_t ibaud, speed_t obaud); 440 extern void tty_encode_baud_rate(struct tty_struct *tty, 441 speed_t ibaud, speed_t obaud); 442 443 /** 444 * tty_get_baud_rate - get tty bit rates 445 * @tty: tty to query 446 * 447 * Returns the baud rate as an integer for this terminal. The 448 * termios lock must be held by the caller and the terminal bit 449 * flags may be updated. 450 * 451 * Locking: none 452 */ 453 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 454 { 455 return tty_termios_baud_rate(&tty->termios); 456 } 457 458 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 459 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 460 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 461 462 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 463 extern void tty_ldisc_deref(struct tty_ldisc *); 464 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 465 extern void tty_ldisc_hangup(struct tty_struct *tty); 466 extern const struct file_operations tty_ldiscs_proc_fops; 467 468 extern void tty_wakeup(struct tty_struct *tty); 469 extern void tty_ldisc_flush(struct tty_struct *tty); 470 471 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 472 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 473 unsigned int cmd, unsigned long arg); 474 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 475 extern void tty_default_fops(struct file_operations *fops); 476 extern struct tty_struct *alloc_tty_struct(void); 477 extern int tty_alloc_file(struct file *file); 478 extern void tty_add_file(struct tty_struct *tty, struct file *file); 479 extern void tty_free_file(struct file *file); 480 extern void free_tty_struct(struct tty_struct *tty); 481 extern void initialize_tty_struct(struct tty_struct *tty, 482 struct tty_driver *driver, int idx); 483 extern void deinitialize_tty_struct(struct tty_struct *tty); 484 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 485 extern int tty_release(struct inode *inode, struct file *filp); 486 extern int tty_init_termios(struct tty_struct *tty); 487 extern int tty_standard_install(struct tty_driver *driver, 488 struct tty_struct *tty); 489 490 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 491 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 492 493 extern struct mutex tty_mutex; 494 extern spinlock_t tty_files_lock; 495 496 extern void tty_write_unlock(struct tty_struct *tty); 497 extern int tty_write_lock(struct tty_struct *tty, int ndelay); 498 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 499 500 extern void tty_port_init(struct tty_port *port); 501 extern void tty_port_link_device(struct tty_port *port, 502 struct tty_driver *driver, unsigned index); 503 extern struct device *tty_port_register_device(struct tty_port *port, 504 struct tty_driver *driver, unsigned index, 505 struct device *device); 506 extern struct device *tty_port_register_device_attr(struct tty_port *port, 507 struct tty_driver *driver, unsigned index, 508 struct device *device, void *drvdata, 509 const struct attribute_group **attr_grp); 510 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 511 extern void tty_port_free_xmit_buf(struct tty_port *port); 512 extern void tty_port_destroy(struct tty_port *port); 513 extern void tty_port_put(struct tty_port *port); 514 515 static inline struct tty_port *tty_port_get(struct tty_port *port) 516 { 517 if (port) 518 kref_get(&port->kref); 519 return port; 520 } 521 522 /* If the cts flow control is enabled, return true. */ 523 static inline bool tty_port_cts_enabled(struct tty_port *port) 524 { 525 return port->flags & ASYNC_CTS_FLOW; 526 } 527 528 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 529 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 530 extern int tty_port_carrier_raised(struct tty_port *port); 531 extern void tty_port_raise_dtr_rts(struct tty_port *port); 532 extern void tty_port_lower_dtr_rts(struct tty_port *port); 533 extern void tty_port_hangup(struct tty_port *port); 534 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 535 extern void tty_port_tty_wakeup(struct tty_port *port); 536 extern int tty_port_block_til_ready(struct tty_port *port, 537 struct tty_struct *tty, struct file *filp); 538 extern int tty_port_close_start(struct tty_port *port, 539 struct tty_struct *tty, struct file *filp); 540 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 541 extern void tty_port_close(struct tty_port *port, 542 struct tty_struct *tty, struct file *filp); 543 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 544 struct tty_struct *tty); 545 extern int tty_port_open(struct tty_port *port, 546 struct tty_struct *tty, struct file *filp); 547 static inline int tty_port_users(struct tty_port *port) 548 { 549 return port->count + port->blocked_open; 550 } 551 552 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 553 extern int tty_unregister_ldisc(int disc); 554 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 555 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 556 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 557 extern void tty_ldisc_init(struct tty_struct *tty); 558 extern void tty_ldisc_deinit(struct tty_struct *tty); 559 extern void tty_ldisc_begin(void); 560 561 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 562 char *f, int count) 563 { 564 if (ld->ops->receive_buf2) 565 count = ld->ops->receive_buf2(ld->tty, p, f, count); 566 else { 567 count = min_t(int, count, ld->tty->receive_room); 568 if (count) 569 ld->ops->receive_buf(ld->tty, p, f, count); 570 } 571 return count; 572 } 573 574 575 /* n_tty.c */ 576 extern struct tty_ldisc_ops tty_ldisc_N_TTY; 577 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 578 579 /* tty_audit.c */ 580 #ifdef CONFIG_AUDIT 581 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 582 size_t size, unsigned icanon); 583 extern void tty_audit_exit(void); 584 extern void tty_audit_fork(struct signal_struct *sig); 585 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 586 extern void tty_audit_push(struct tty_struct *tty); 587 extern int tty_audit_push_current(void); 588 #else 589 static inline void tty_audit_add_data(struct tty_struct *tty, 590 unsigned char *data, size_t size, unsigned icanon) 591 { 592 } 593 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 594 { 595 } 596 static inline void tty_audit_exit(void) 597 { 598 } 599 static inline void tty_audit_fork(struct signal_struct *sig) 600 { 601 } 602 static inline void tty_audit_push(struct tty_struct *tty) 603 { 604 } 605 static inline int tty_audit_push_current(void) 606 { 607 return 0; 608 } 609 #endif 610 611 /* tty_ioctl.c */ 612 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 613 unsigned int cmd, unsigned long arg); 614 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 615 unsigned int cmd, unsigned long arg); 616 617 /* serial.c */ 618 619 extern void serial_console_init(void); 620 621 /* pcxx.c */ 622 623 extern int pcxe_open(struct tty_struct *tty, struct file *filp); 624 625 /* vt.c */ 626 627 extern int vt_ioctl(struct tty_struct *tty, 628 unsigned int cmd, unsigned long arg); 629 630 extern long vt_compat_ioctl(struct tty_struct *tty, 631 unsigned int cmd, unsigned long arg); 632 633 /* tty_mutex.c */ 634 /* functions for preparation of BKL removal */ 635 extern void __lockfunc tty_lock(struct tty_struct *tty); 636 extern void __lockfunc tty_unlock(struct tty_struct *tty); 637 extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 638 struct tty_struct *tty2); 639 extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 640 struct tty_struct *tty2); 641 642 /* 643 * this shall be called only from where BTM is held (like close) 644 * 645 * We need this to ensure nobody waits for us to finish while we are waiting. 646 * Without this we were encountering system stalls. 647 * 648 * This should be indeed removed with BTM removal later. 649 * 650 * Locking: BTM required. Nobody is allowed to hold port->mutex. 651 */ 652 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 653 long timeout) 654 { 655 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 656 tty_wait_until_sent(tty, timeout); 657 tty_lock(tty); 658 } 659 660 /* 661 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 662 * 663 * The condition we are waiting for might take a long time to 664 * become true, or might depend on another thread taking the 665 * BTM. In either case, we need to drop the BTM to guarantee 666 * forward progress. This is a leftover from the conversion 667 * from the BKL and should eventually get removed as the BTM 668 * falls out of use. 669 * 670 * Do not use in new code. 671 */ 672 #define wait_event_interruptible_tty(tty, wq, condition) \ 673 ({ \ 674 int __ret = 0; \ 675 if (!(condition)) { \ 676 __wait_event_interruptible_tty(tty, wq, condition, __ret); \ 677 } \ 678 __ret; \ 679 }) 680 681 #define __wait_event_interruptible_tty(tty, wq, condition, ret) \ 682 do { \ 683 DEFINE_WAIT(__wait); \ 684 \ 685 for (;;) { \ 686 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ 687 if (condition) \ 688 break; \ 689 if (!signal_pending(current)) { \ 690 tty_unlock(tty); \ 691 schedule(); \ 692 tty_lock(tty); \ 693 continue; \ 694 } \ 695 ret = -ERESTARTSYS; \ 696 break; \ 697 } \ 698 finish_wait(&wq, &__wait); \ 699 } while (0) 700 701 #ifdef CONFIG_PROC_FS 702 extern void proc_tty_register_driver(struct tty_driver *); 703 extern void proc_tty_unregister_driver(struct tty_driver *); 704 #else 705 static inline void proc_tty_register_driver(struct tty_driver *d) {} 706 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 707 #endif 708 709 #endif 710