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 int flags; 43 /* Data points here */ 44 unsigned long data[0]; 45 }; 46 47 /* Values for .flags field of tty_buffer */ 48 #define TTYB_NORMAL 1 /* buffer has no flags buffer */ 49 50 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 51 { 52 return ((unsigned char *)b->data) + ofs; 53 } 54 55 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 56 { 57 return (char *)char_buf_ptr(b, ofs) + b->size; 58 } 59 60 struct tty_bufhead { 61 struct tty_buffer *head; /* Queue head */ 62 struct work_struct work; 63 struct mutex lock; 64 atomic_t priority; 65 struct tty_buffer sentinel; 66 struct llist_head free; /* Free queue head */ 67 atomic_t mem_used; /* In-use buffers excluding free list */ 68 int mem_limit; 69 struct tty_buffer *tail; /* Active buffer */ 70 }; 71 /* 72 * When a break, frame error, or parity error happens, these codes are 73 * stuffed into the flags buffer. 74 */ 75 #define TTY_NORMAL 0 76 #define TTY_BREAK 1 77 #define TTY_FRAME 2 78 #define TTY_PARITY 3 79 #define TTY_OVERRUN 4 80 81 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 82 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 83 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 84 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 85 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 86 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 87 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 88 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 89 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 90 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 91 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 92 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 93 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 94 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 95 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 96 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 97 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 98 99 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 100 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 101 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 102 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 103 104 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 105 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 106 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 107 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 108 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 109 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 110 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 111 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 112 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 113 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 114 #define I_IXON(tty) _I_FLAG((tty), IXON) 115 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 116 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 117 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 118 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 119 120 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 121 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 122 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 123 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 124 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 125 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 126 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 127 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 128 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 129 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 130 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 131 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 132 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 133 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 134 135 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 136 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 137 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 138 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 139 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 140 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 141 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 142 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 143 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 144 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 145 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 146 147 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 148 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 149 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 150 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 151 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 152 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 153 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 154 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 155 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 156 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 157 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 158 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 159 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 160 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 161 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 162 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 163 164 struct device; 165 struct signal_struct; 166 167 /* 168 * Port level information. Each device keeps its own port level information 169 * so provide a common structure for those ports wanting to use common support 170 * routines. 171 * 172 * The tty port has a different lifetime to the tty so must be kept apart. 173 * In addition be careful as tty -> port mappings are valid for the life 174 * of the tty object but in many cases port -> tty mappings are valid only 175 * until a hangup so don't use the wrong path. 176 */ 177 178 struct tty_port; 179 180 struct tty_port_operations { 181 /* Return 1 if the carrier is raised */ 182 int (*carrier_raised)(struct tty_port *port); 183 /* Control the DTR line */ 184 void (*dtr_rts)(struct tty_port *port, int raise); 185 /* Called when the last close completes or a hangup finishes 186 IFF the port was initialized. Do not use to free resources. Called 187 under the port mutex to serialize against activate/shutdowns */ 188 void (*shutdown)(struct tty_port *port); 189 /* Called under the port mutex from tty_port_open, serialized using 190 the port mutex */ 191 /* FIXME: long term getting the tty argument *out* of this would be 192 good for consoles */ 193 int (*activate)(struct tty_port *port, struct tty_struct *tty); 194 /* Called on the final put of a port */ 195 void (*destruct)(struct tty_port *port); 196 }; 197 198 struct tty_port { 199 struct tty_bufhead buf; /* Locked internally */ 200 struct tty_struct *tty; /* Back pointer */ 201 struct tty_struct *itty; /* internal back ptr */ 202 const struct tty_port_operations *ops; /* Port operations */ 203 spinlock_t lock; /* Lock protecting tty field */ 204 int blocked_open; /* Waiting to open */ 205 int count; /* Usage count */ 206 wait_queue_head_t open_wait; /* Open waiters */ 207 wait_queue_head_t close_wait; /* Close waiters */ 208 wait_queue_head_t delta_msr_wait; /* Modem status change */ 209 unsigned long flags; /* TTY flags ASY_*/ 210 unsigned char console:1, /* port is a console */ 211 low_latency:1; /* optional: tune for latency */ 212 struct mutex mutex; /* Locking */ 213 struct mutex buf_mutex; /* Buffer alloc lock */ 214 unsigned char *xmit_buf; /* Optional buffer */ 215 unsigned int close_delay; /* Close port delay */ 216 unsigned int closing_wait; /* Delay for output */ 217 int drain_delay; /* Set to zero if no pure time 218 based drain is needed else 219 set to size of fifo */ 220 struct kref kref; /* Ref counter */ 221 }; 222 223 /* 224 * Where all of the state associated with a tty is kept while the tty 225 * is open. Since the termios state should be kept even if the tty 226 * has been closed --- for things like the baud rate, etc --- it is 227 * not stored here, but rather a pointer to the real state is stored 228 * here. Possible the winsize structure should have the same 229 * treatment, but (1) the default 80x24 is usually right and (2) it's 230 * most often used by a windowing system, which will set the correct 231 * size each time the window is created or resized anyway. 232 * - TYT, 9/14/92 233 */ 234 235 struct tty_operations; 236 237 struct tty_struct { 238 int magic; 239 struct kref kref; 240 struct device *dev; 241 struct tty_driver *driver; 242 const struct tty_operations *ops; 243 int index; 244 245 /* Protects ldisc changes: Lock tty not pty */ 246 struct ld_semaphore ldisc_sem; 247 struct tty_ldisc *ldisc; 248 249 struct mutex atomic_write_lock; 250 struct mutex legacy_mutex; 251 struct mutex throttle_mutex; 252 struct rw_semaphore termios_rwsem; 253 struct mutex winsize_mutex; 254 spinlock_t ctrl_lock; 255 spinlock_t flow_lock; 256 /* Termios values are protected by the termios rwsem */ 257 struct ktermios termios, termios_locked; 258 struct termiox *termiox; /* May be NULL for unsupported */ 259 char name[64]; 260 struct pid *pgrp; /* Protected by ctrl lock */ 261 struct pid *session; 262 unsigned long flags; 263 int count; 264 struct winsize winsize; /* winsize_mutex */ 265 unsigned long stopped:1, /* flow_lock */ 266 flow_stopped:1, 267 unused:BITS_PER_LONG - 2; 268 int hw_stopped; 269 unsigned long ctrl_status:8, /* ctrl_lock */ 270 packet:1, 271 unused_ctrl:BITS_PER_LONG - 9; 272 unsigned int receive_room; /* Bytes free for queue */ 273 int flow_change; 274 275 struct tty_struct *link; 276 struct fasync_struct *fasync; 277 int alt_speed; /* For magic substitution of 38400 bps */ 278 wait_queue_head_t write_wait; 279 wait_queue_head_t read_wait; 280 struct work_struct hangup_work; 281 void *disc_data; 282 void *driver_data; 283 struct list_head tty_files; 284 285 #define N_TTY_BUF_SIZE 4096 286 287 unsigned char closing:1; 288 unsigned char *write_buf; 289 int write_cnt; 290 /* If the tty has a pending do_SAK, queue it here - akpm */ 291 struct work_struct SAK_work; 292 struct tty_port *port; 293 }; 294 295 /* Each of a tty's open files has private_data pointing to tty_file_private */ 296 struct tty_file_private { 297 struct tty_struct *tty; 298 struct file *file; 299 struct list_head list; 300 }; 301 302 /* tty magic number */ 303 #define TTY_MAGIC 0x5401 304 305 /* 306 * These bits are used in the flags field of the tty structure. 307 * 308 * So that interrupts won't be able to mess up the queues, 309 * copy_to_cooked must be atomic with respect to itself, as must 310 * tty->write. Thus, you must use the inline functions set_bit() and 311 * clear_bit() to make things atomic. 312 */ 313 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 314 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 315 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 316 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 317 #define TTY_DEBUG 4 /* Debugging */ 318 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 319 #define TTY_CLOSING 7 /* ->close() in progress */ 320 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 321 #define TTY_PTY_LOCK 16 /* pty private */ 322 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 323 #define TTY_HUPPED 18 /* Post driver->hangup() */ 324 #define TTY_HUPPING 21 /* ->hangup() in progress */ 325 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 326 327 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 328 329 /* Values for tty->flow_change */ 330 #define TTY_THROTTLE_SAFE 1 331 #define TTY_UNTHROTTLE_SAFE 2 332 333 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 334 { 335 tty->flow_change = val; 336 } 337 338 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 339 { 340 tty->flow_change = val; 341 smp_mb(); 342 } 343 344 #ifdef CONFIG_TTY 345 extern void console_init(void); 346 extern void tty_kref_put(struct tty_struct *tty); 347 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 348 extern void tty_vhangup_self(void); 349 extern void disassociate_ctty(int priv); 350 extern dev_t tty_devnum(struct tty_struct *tty); 351 extern void proc_clear_tty(struct task_struct *p); 352 extern struct tty_struct *get_current_tty(void); 353 /* tty_io.c */ 354 extern int __init tty_init(void); 355 #else 356 static inline void console_init(void) 357 { } 358 static inline void tty_kref_put(struct tty_struct *tty) 359 { } 360 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 361 { return NULL; } 362 static inline void tty_vhangup_self(void) 363 { } 364 static inline void disassociate_ctty(int priv) 365 { } 366 static inline dev_t tty_devnum(struct tty_struct *tty) 367 { return 0; } 368 static inline void proc_clear_tty(struct task_struct *p) 369 { } 370 static inline struct tty_struct *get_current_tty(void) 371 { return NULL; } 372 /* tty_io.c */ 373 static inline int __init tty_init(void) 374 { return 0; } 375 #endif 376 377 extern void tty_write_flush(struct tty_struct *); 378 379 extern struct ktermios tty_std_termios; 380 381 extern int vcs_init(void); 382 383 extern struct class *tty_class; 384 385 /** 386 * tty_kref_get - get a tty reference 387 * @tty: tty device 388 * 389 * Return a new reference to a tty object. The caller must hold 390 * sufficient locks/counts to ensure that their existing reference cannot 391 * go away 392 */ 393 394 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 395 { 396 if (tty) 397 kref_get(&tty->kref); 398 return tty; 399 } 400 401 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 402 const char *routine); 403 extern char *tty_name(struct tty_struct *tty, char *buf); 404 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 405 extern int tty_check_change(struct tty_struct *tty); 406 extern void __stop_tty(struct tty_struct *tty); 407 extern void stop_tty(struct tty_struct *tty); 408 extern void __start_tty(struct tty_struct *tty); 409 extern void start_tty(struct tty_struct *tty); 410 extern int tty_register_driver(struct tty_driver *driver); 411 extern int tty_unregister_driver(struct tty_driver *driver); 412 extern struct device *tty_register_device(struct tty_driver *driver, 413 unsigned index, struct device *dev); 414 extern struct device *tty_register_device_attr(struct tty_driver *driver, 415 unsigned index, struct device *device, 416 void *drvdata, 417 const struct attribute_group **attr_grp); 418 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 419 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 420 int buflen); 421 extern void tty_write_message(struct tty_struct *tty, char *msg); 422 extern int tty_send_xchar(struct tty_struct *tty, char ch); 423 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 424 extern int tty_chars_in_buffer(struct tty_struct *tty); 425 extern int tty_write_room(struct tty_struct *tty); 426 extern void tty_driver_flush_buffer(struct tty_struct *tty); 427 extern void tty_throttle(struct tty_struct *tty); 428 extern void tty_unthrottle(struct tty_struct *tty); 429 extern int tty_throttle_safe(struct tty_struct *tty); 430 extern int tty_unthrottle_safe(struct tty_struct *tty); 431 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 432 extern void tty_driver_remove_tty(struct tty_driver *driver, 433 struct tty_struct *tty); 434 extern void tty_free_termios(struct tty_struct *tty); 435 extern int is_current_pgrp_orphaned(void); 436 extern int is_ignored(int sig); 437 extern int tty_signal(int sig, struct tty_struct *tty); 438 extern void tty_hangup(struct tty_struct *tty); 439 extern void tty_vhangup(struct tty_struct *tty); 440 extern void tty_unhangup(struct file *filp); 441 extern int tty_hung_up_p(struct file *filp); 442 extern void do_SAK(struct tty_struct *tty); 443 extern void __do_SAK(struct tty_struct *tty); 444 extern void no_tty(void); 445 extern void tty_flush_to_ldisc(struct tty_struct *tty); 446 extern void tty_buffer_free_all(struct tty_port *port); 447 extern void tty_buffer_flush(struct tty_struct *tty); 448 extern void tty_buffer_init(struct tty_port *port); 449 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 450 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 451 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 452 speed_t ibaud, speed_t obaud); 453 extern void tty_encode_baud_rate(struct tty_struct *tty, 454 speed_t ibaud, speed_t obaud); 455 456 /** 457 * tty_get_baud_rate - get tty bit rates 458 * @tty: tty to query 459 * 460 * Returns the baud rate as an integer for this terminal. The 461 * termios lock must be held by the caller and the terminal bit 462 * flags may be updated. 463 * 464 * Locking: none 465 */ 466 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 467 { 468 return tty_termios_baud_rate(&tty->termios); 469 } 470 471 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 472 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 473 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 474 475 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 476 extern void tty_ldisc_deref(struct tty_ldisc *); 477 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 478 extern void tty_ldisc_hangup(struct tty_struct *tty); 479 extern const struct file_operations tty_ldiscs_proc_fops; 480 481 extern void tty_wakeup(struct tty_struct *tty); 482 extern void tty_ldisc_flush(struct tty_struct *tty); 483 484 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 485 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 486 unsigned int cmd, unsigned long arg); 487 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 488 extern void tty_default_fops(struct file_operations *fops); 489 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 490 extern int tty_alloc_file(struct file *file); 491 extern void tty_add_file(struct tty_struct *tty, struct file *file); 492 extern void tty_free_file(struct file *file); 493 extern void free_tty_struct(struct tty_struct *tty); 494 extern void deinitialize_tty_struct(struct tty_struct *tty); 495 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 496 extern int tty_release(struct inode *inode, struct file *filp); 497 extern int tty_init_termios(struct tty_struct *tty); 498 extern int tty_standard_install(struct tty_driver *driver, 499 struct tty_struct *tty); 500 501 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 502 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 503 504 extern struct mutex tty_mutex; 505 extern spinlock_t tty_files_lock; 506 507 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 508 509 extern void tty_port_init(struct tty_port *port); 510 extern void tty_port_link_device(struct tty_port *port, 511 struct tty_driver *driver, unsigned index); 512 extern struct device *tty_port_register_device(struct tty_port *port, 513 struct tty_driver *driver, unsigned index, 514 struct device *device); 515 extern struct device *tty_port_register_device_attr(struct tty_port *port, 516 struct tty_driver *driver, unsigned index, 517 struct device *device, void *drvdata, 518 const struct attribute_group **attr_grp); 519 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 520 extern void tty_port_free_xmit_buf(struct tty_port *port); 521 extern void tty_port_destroy(struct tty_port *port); 522 extern void tty_port_put(struct tty_port *port); 523 524 static inline struct tty_port *tty_port_get(struct tty_port *port) 525 { 526 if (port && kref_get_unless_zero(&port->kref)) 527 return port; 528 return NULL; 529 } 530 531 /* If the cts flow control is enabled, return true. */ 532 static inline bool tty_port_cts_enabled(struct tty_port *port) 533 { 534 return port->flags & ASYNC_CTS_FLOW; 535 } 536 537 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 538 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 539 extern int tty_port_carrier_raised(struct tty_port *port); 540 extern void tty_port_raise_dtr_rts(struct tty_port *port); 541 extern void tty_port_lower_dtr_rts(struct tty_port *port); 542 extern void tty_port_hangup(struct tty_port *port); 543 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 544 extern void tty_port_tty_wakeup(struct tty_port *port); 545 extern int tty_port_block_til_ready(struct tty_port *port, 546 struct tty_struct *tty, struct file *filp); 547 extern int tty_port_close_start(struct tty_port *port, 548 struct tty_struct *tty, struct file *filp); 549 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 550 extern void tty_port_close(struct tty_port *port, 551 struct tty_struct *tty, struct file *filp); 552 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 553 struct tty_struct *tty); 554 extern int tty_port_open(struct tty_port *port, 555 struct tty_struct *tty, struct file *filp); 556 static inline int tty_port_users(struct tty_port *port) 557 { 558 return port->count + port->blocked_open; 559 } 560 561 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 562 extern int tty_unregister_ldisc(int disc); 563 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 564 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 565 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 566 extern void tty_ldisc_init(struct tty_struct *tty); 567 extern void tty_ldisc_deinit(struct tty_struct *tty); 568 extern void tty_ldisc_begin(void); 569 570 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 571 char *f, int count) 572 { 573 if (ld->ops->receive_buf2) 574 count = ld->ops->receive_buf2(ld->tty, p, f, count); 575 else { 576 count = min_t(int, count, ld->tty->receive_room); 577 if (count) 578 ld->ops->receive_buf(ld->tty, p, f, count); 579 } 580 return count; 581 } 582 583 584 /* n_tty.c */ 585 extern struct tty_ldisc_ops tty_ldisc_N_TTY; 586 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 587 588 /* tty_audit.c */ 589 #ifdef CONFIG_AUDIT 590 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 591 size_t size, unsigned icanon); 592 extern void tty_audit_exit(void); 593 extern void tty_audit_fork(struct signal_struct *sig); 594 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 595 extern void tty_audit_push(struct tty_struct *tty); 596 extern int tty_audit_push_current(void); 597 #else 598 static inline void tty_audit_add_data(struct tty_struct *tty, 599 unsigned char *data, size_t size, unsigned icanon) 600 { 601 } 602 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 603 { 604 } 605 static inline void tty_audit_exit(void) 606 { 607 } 608 static inline void tty_audit_fork(struct signal_struct *sig) 609 { 610 } 611 static inline void tty_audit_push(struct tty_struct *tty) 612 { 613 } 614 static inline int tty_audit_push_current(void) 615 { 616 return 0; 617 } 618 #endif 619 620 /* tty_ioctl.c */ 621 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 622 unsigned int cmd, unsigned long arg); 623 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 624 unsigned int cmd, unsigned long arg); 625 626 /* serial.c */ 627 628 extern void serial_console_init(void); 629 630 /* pcxx.c */ 631 632 extern int pcxe_open(struct tty_struct *tty, struct file *filp); 633 634 /* vt.c */ 635 636 extern int vt_ioctl(struct tty_struct *tty, 637 unsigned int cmd, unsigned long arg); 638 639 extern long vt_compat_ioctl(struct tty_struct *tty, 640 unsigned int cmd, unsigned long arg); 641 642 /* tty_mutex.c */ 643 /* functions for preparation of BKL removal */ 644 extern void __lockfunc tty_lock(struct tty_struct *tty); 645 extern void __lockfunc tty_unlock(struct tty_struct *tty); 646 extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 647 struct tty_struct *tty2); 648 extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 649 struct tty_struct *tty2); 650 651 /* 652 * this shall be called only from where BTM is held (like close) 653 * 654 * We need this to ensure nobody waits for us to finish while we are waiting. 655 * Without this we were encountering system stalls. 656 * 657 * This should be indeed removed with BTM removal later. 658 * 659 * Locking: BTM required. Nobody is allowed to hold port->mutex. 660 */ 661 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 662 long timeout) 663 { 664 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 665 tty_wait_until_sent(tty, timeout); 666 tty_lock(tty); 667 } 668 669 /* 670 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 671 * 672 * The condition we are waiting for might take a long time to 673 * become true, or might depend on another thread taking the 674 * BTM. In either case, we need to drop the BTM to guarantee 675 * forward progress. This is a leftover from the conversion 676 * from the BKL and should eventually get removed as the BTM 677 * falls out of use. 678 * 679 * Do not use in new code. 680 */ 681 #define wait_event_interruptible_tty(tty, wq, condition) \ 682 ({ \ 683 int __ret = 0; \ 684 if (!(condition)) \ 685 __ret = __wait_event_interruptible_tty(tty, wq, \ 686 condition); \ 687 __ret; \ 688 }) 689 690 #define __wait_event_interruptible_tty(tty, wq, condition) \ 691 ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ 692 tty_unlock(tty); \ 693 schedule(); \ 694 tty_lock(tty)) 695 696 #ifdef CONFIG_PROC_FS 697 extern void proc_tty_register_driver(struct tty_driver *); 698 extern void proc_tty_unregister_driver(struct tty_driver *); 699 #else 700 static inline void proc_tty_register_driver(struct tty_driver *d) {} 701 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 702 #endif 703 704 #endif 705