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 * Lock subclasses for tty locks 19 * 20 * TTY_LOCK_NORMAL is for normal ttys and master ptys. 21 * TTY_LOCK_SLAVE is for slave ptys only. 22 * 23 * Lock subclasses are necessary for handling nested locking with pty pairs. 24 * tty locks which use nested locking: 25 * 26 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. 27 * The stable lock order is master pty first, then slave pty. 28 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. 29 * Subclassing this lock enables the slave pty to hold its 30 * termios_rwsem when claiming the master tty_buffer lock. 31 * tty_buffer lock - slave ptys can claim nested buffer lock when handling 32 * signal chars. The stable lock order is slave pty, then 33 * master. 34 */ 35 36 enum { 37 TTY_LOCK_NORMAL = 0, 38 TTY_LOCK_SLAVE, 39 }; 40 41 /* 42 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 43 * hardcoded at present.) 44 */ 45 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 46 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 47 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 48 49 /* 50 * This character is the same as _POSIX_VDISABLE: it cannot be used as 51 * a c_cc[] character, but indicates that a particular special character 52 * isn't in use (eg VINTR has no character etc) 53 */ 54 #define __DISABLED_CHAR '\0' 55 56 struct tty_buffer { 57 union { 58 struct tty_buffer *next; 59 struct llist_node free; 60 }; 61 int used; 62 int size; 63 int commit; 64 int read; 65 int flags; 66 /* Data points here */ 67 unsigned long data[0]; 68 }; 69 70 /* Values for .flags field of tty_buffer */ 71 #define TTYB_NORMAL 1 /* buffer has no flags buffer */ 72 73 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 74 { 75 return ((unsigned char *)b->data) + ofs; 76 } 77 78 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 79 { 80 return (char *)char_buf_ptr(b, ofs) + b->size; 81 } 82 83 struct tty_bufhead { 84 struct tty_buffer *head; /* Queue head */ 85 struct work_struct work; 86 struct mutex lock; 87 atomic_t priority; 88 struct tty_buffer sentinel; 89 struct llist_head free; /* Free queue head */ 90 atomic_t mem_used; /* In-use buffers excluding free list */ 91 int mem_limit; 92 struct tty_buffer *tail; /* Active buffer */ 93 }; 94 /* 95 * When a break, frame error, or parity error happens, these codes are 96 * stuffed into the flags buffer. 97 */ 98 #define TTY_NORMAL 0 99 #define TTY_BREAK 1 100 #define TTY_FRAME 2 101 #define TTY_PARITY 3 102 #define TTY_OVERRUN 4 103 104 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 105 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 106 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 107 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 108 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 109 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 110 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 111 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 112 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 113 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 114 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 115 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 116 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 117 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 118 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 119 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 120 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 121 122 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 123 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 124 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 125 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 126 127 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 128 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 129 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 130 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 131 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 132 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 133 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 134 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 135 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 136 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 137 #define I_IXON(tty) _I_FLAG((tty), IXON) 138 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 139 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 140 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 141 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 142 143 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 144 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 145 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 146 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 147 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 148 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 149 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 150 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 151 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 152 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 153 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 154 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 155 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 156 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 157 158 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 159 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 160 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 161 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 162 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 163 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 164 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 165 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 166 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 167 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 168 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 169 170 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 171 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 172 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 173 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 174 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 175 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 176 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 177 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 178 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 179 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 180 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 181 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 182 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 183 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 184 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 185 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 186 187 struct device; 188 struct signal_struct; 189 190 /* 191 * Port level information. Each device keeps its own port level information 192 * so provide a common structure for those ports wanting to use common support 193 * routines. 194 * 195 * The tty port has a different lifetime to the tty so must be kept apart. 196 * In addition be careful as tty -> port mappings are valid for the life 197 * of the tty object but in many cases port -> tty mappings are valid only 198 * until a hangup so don't use the wrong path. 199 */ 200 201 struct tty_port; 202 203 struct tty_port_operations { 204 /* Return 1 if the carrier is raised */ 205 int (*carrier_raised)(struct tty_port *port); 206 /* Control the DTR line */ 207 void (*dtr_rts)(struct tty_port *port, int raise); 208 /* Called when the last close completes or a hangup finishes 209 IFF the port was initialized. Do not use to free resources. Called 210 under the port mutex to serialize against activate/shutdowns */ 211 void (*shutdown)(struct tty_port *port); 212 /* Called under the port mutex from tty_port_open, serialized using 213 the port mutex */ 214 /* FIXME: long term getting the tty argument *out* of this would be 215 good for consoles */ 216 int (*activate)(struct tty_port *port, struct tty_struct *tty); 217 /* Called on the final put of a port */ 218 void (*destruct)(struct tty_port *port); 219 }; 220 221 struct tty_port { 222 struct tty_bufhead buf; /* Locked internally */ 223 struct tty_struct *tty; /* Back pointer */ 224 struct tty_struct *itty; /* internal back ptr */ 225 const struct tty_port_operations *ops; /* Port operations */ 226 spinlock_t lock; /* Lock protecting tty field */ 227 int blocked_open; /* Waiting to open */ 228 int count; /* Usage count */ 229 wait_queue_head_t open_wait; /* Open waiters */ 230 wait_queue_head_t close_wait; /* Close waiters */ 231 wait_queue_head_t delta_msr_wait; /* Modem status change */ 232 unsigned long flags; /* TTY flags ASY_*/ 233 unsigned char console:1, /* port is a console */ 234 low_latency:1; /* optional: tune for latency */ 235 struct mutex mutex; /* Locking */ 236 struct mutex buf_mutex; /* Buffer alloc lock */ 237 unsigned char *xmit_buf; /* Optional buffer */ 238 unsigned int close_delay; /* Close port delay */ 239 unsigned int closing_wait; /* Delay for output */ 240 int drain_delay; /* Set to zero if no pure time 241 based drain is needed else 242 set to size of fifo */ 243 struct kref kref; /* Ref counter */ 244 }; 245 246 /* 247 * Where all of the state associated with a tty is kept while the tty 248 * is open. Since the termios state should be kept even if the tty 249 * has been closed --- for things like the baud rate, etc --- it is 250 * not stored here, but rather a pointer to the real state is stored 251 * here. Possible the winsize structure should have the same 252 * treatment, but (1) the default 80x24 is usually right and (2) it's 253 * most often used by a windowing system, which will set the correct 254 * size each time the window is created or resized anyway. 255 * - TYT, 9/14/92 256 */ 257 258 struct tty_operations; 259 260 struct tty_struct { 261 int magic; 262 struct kref kref; 263 struct device *dev; 264 struct tty_driver *driver; 265 const struct tty_operations *ops; 266 int index; 267 268 /* Protects ldisc changes: Lock tty not pty */ 269 struct ld_semaphore ldisc_sem; 270 struct tty_ldisc *ldisc; 271 272 struct mutex atomic_write_lock; 273 struct mutex legacy_mutex; 274 struct mutex throttle_mutex; 275 struct rw_semaphore termios_rwsem; 276 struct mutex winsize_mutex; 277 spinlock_t ctrl_lock; 278 spinlock_t flow_lock; 279 /* Termios values are protected by the termios rwsem */ 280 struct ktermios termios, termios_locked; 281 struct termiox *termiox; /* May be NULL for unsupported */ 282 char name[64]; 283 struct pid *pgrp; /* Protected by ctrl lock */ 284 struct pid *session; 285 unsigned long flags; 286 int count; 287 struct winsize winsize; /* winsize_mutex */ 288 unsigned long stopped:1, /* flow_lock */ 289 flow_stopped:1, 290 unused:BITS_PER_LONG - 2; 291 int hw_stopped; 292 unsigned long ctrl_status:8, /* ctrl_lock */ 293 packet:1, 294 unused_ctrl:BITS_PER_LONG - 9; 295 unsigned int receive_room; /* Bytes free for queue */ 296 int flow_change; 297 298 struct tty_struct *link; 299 struct fasync_struct *fasync; 300 int alt_speed; /* For magic substitution of 38400 bps */ 301 wait_queue_head_t write_wait; 302 wait_queue_head_t read_wait; 303 struct work_struct hangup_work; 304 void *disc_data; 305 void *driver_data; 306 struct list_head tty_files; 307 308 #define N_TTY_BUF_SIZE 4096 309 310 int closing; 311 unsigned char *write_buf; 312 int write_cnt; 313 /* If the tty has a pending do_SAK, queue it here - akpm */ 314 struct work_struct SAK_work; 315 struct tty_port *port; 316 }; 317 318 /* Each of a tty's open files has private_data pointing to tty_file_private */ 319 struct tty_file_private { 320 struct tty_struct *tty; 321 struct file *file; 322 struct list_head list; 323 }; 324 325 /* tty magic number */ 326 #define TTY_MAGIC 0x5401 327 328 /* 329 * These bits are used in the flags field of the tty structure. 330 * 331 * So that interrupts won't be able to mess up the queues, 332 * copy_to_cooked must be atomic with respect to itself, as must 333 * tty->write. Thus, you must use the inline functions set_bit() and 334 * clear_bit() to make things atomic. 335 */ 336 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 337 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 338 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 339 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 340 #define TTY_DEBUG 4 /* Debugging */ 341 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 342 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 343 #define TTY_PTY_LOCK 16 /* pty private */ 344 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 345 #define TTY_HUPPED 18 /* Post driver->hangup() */ 346 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 347 348 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 349 350 /* Values for tty->flow_change */ 351 #define TTY_THROTTLE_SAFE 1 352 #define TTY_UNTHROTTLE_SAFE 2 353 354 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 355 { 356 tty->flow_change = val; 357 } 358 359 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 360 { 361 tty->flow_change = val; 362 smp_mb(); 363 } 364 365 #ifdef CONFIG_TTY 366 extern void console_init(void); 367 extern void tty_kref_put(struct tty_struct *tty); 368 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 369 extern void tty_vhangup_self(void); 370 extern void disassociate_ctty(int priv); 371 extern dev_t tty_devnum(struct tty_struct *tty); 372 extern void proc_clear_tty(struct task_struct *p); 373 extern struct tty_struct *get_current_tty(void); 374 /* tty_io.c */ 375 extern int __init tty_init(void); 376 #else 377 static inline void console_init(void) 378 { } 379 static inline void tty_kref_put(struct tty_struct *tty) 380 { } 381 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 382 { return NULL; } 383 static inline void tty_vhangup_self(void) 384 { } 385 static inline void disassociate_ctty(int priv) 386 { } 387 static inline dev_t tty_devnum(struct tty_struct *tty) 388 { return 0; } 389 static inline void proc_clear_tty(struct task_struct *p) 390 { } 391 static inline struct tty_struct *get_current_tty(void) 392 { return NULL; } 393 /* tty_io.c */ 394 static inline int __init tty_init(void) 395 { return 0; } 396 #endif 397 398 extern void tty_write_flush(struct tty_struct *); 399 400 extern struct ktermios tty_std_termios; 401 402 extern int vcs_init(void); 403 404 extern struct class *tty_class; 405 406 /** 407 * tty_kref_get - get a tty reference 408 * @tty: tty device 409 * 410 * Return a new reference to a tty object. The caller must hold 411 * sufficient locks/counts to ensure that their existing reference cannot 412 * go away 413 */ 414 415 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 416 { 417 if (tty) 418 kref_get(&tty->kref); 419 return tty; 420 } 421 422 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 423 const char *routine); 424 extern char *tty_name(struct tty_struct *tty, char *buf); 425 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 426 extern int tty_check_change(struct tty_struct *tty); 427 extern void __stop_tty(struct tty_struct *tty); 428 extern void stop_tty(struct tty_struct *tty); 429 extern void __start_tty(struct tty_struct *tty); 430 extern void start_tty(struct tty_struct *tty); 431 extern int tty_register_driver(struct tty_driver *driver); 432 extern int tty_unregister_driver(struct tty_driver *driver); 433 extern struct device *tty_register_device(struct tty_driver *driver, 434 unsigned index, struct device *dev); 435 extern struct device *tty_register_device_attr(struct tty_driver *driver, 436 unsigned index, struct device *device, 437 void *drvdata, 438 const struct attribute_group **attr_grp); 439 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 440 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 441 int buflen); 442 extern void tty_write_message(struct tty_struct *tty, char *msg); 443 extern int tty_send_xchar(struct tty_struct *tty, char ch); 444 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 445 extern int tty_chars_in_buffer(struct tty_struct *tty); 446 extern int tty_write_room(struct tty_struct *tty); 447 extern void tty_driver_flush_buffer(struct tty_struct *tty); 448 extern void tty_throttle(struct tty_struct *tty); 449 extern void tty_unthrottle(struct tty_struct *tty); 450 extern int tty_throttle_safe(struct tty_struct *tty); 451 extern int tty_unthrottle_safe(struct tty_struct *tty); 452 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 453 extern void tty_driver_remove_tty(struct tty_driver *driver, 454 struct tty_struct *tty); 455 extern void tty_free_termios(struct tty_struct *tty); 456 extern int is_current_pgrp_orphaned(void); 457 extern int is_ignored(int sig); 458 extern int tty_signal(int sig, struct tty_struct *tty); 459 extern void tty_hangup(struct tty_struct *tty); 460 extern void tty_vhangup(struct tty_struct *tty); 461 extern int tty_hung_up_p(struct file *filp); 462 extern void do_SAK(struct tty_struct *tty); 463 extern void __do_SAK(struct tty_struct *tty); 464 extern void no_tty(void); 465 extern void tty_flush_to_ldisc(struct tty_struct *tty); 466 extern void tty_buffer_free_all(struct tty_port *port); 467 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 468 extern void tty_buffer_init(struct tty_port *port); 469 extern void tty_buffer_set_lock_subclass(struct tty_port *port); 470 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 471 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 472 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 473 speed_t ibaud, speed_t obaud); 474 extern void tty_encode_baud_rate(struct tty_struct *tty, 475 speed_t ibaud, speed_t obaud); 476 477 /** 478 * tty_get_baud_rate - get tty bit rates 479 * @tty: tty to query 480 * 481 * Returns the baud rate as an integer for this terminal. The 482 * termios lock must be held by the caller and the terminal bit 483 * flags may be updated. 484 * 485 * Locking: none 486 */ 487 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 488 { 489 return tty_termios_baud_rate(&tty->termios); 490 } 491 492 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 493 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 494 495 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 496 extern void tty_ldisc_deref(struct tty_ldisc *); 497 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 498 extern void tty_ldisc_hangup(struct tty_struct *tty); 499 extern const struct file_operations tty_ldiscs_proc_fops; 500 501 extern void tty_wakeup(struct tty_struct *tty); 502 extern void tty_ldisc_flush(struct tty_struct *tty); 503 504 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 505 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 506 unsigned int cmd, unsigned long arg); 507 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 508 extern void tty_default_fops(struct file_operations *fops); 509 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 510 extern int tty_alloc_file(struct file *file); 511 extern void tty_add_file(struct tty_struct *tty, struct file *file); 512 extern void tty_free_file(struct file *file); 513 extern void free_tty_struct(struct tty_struct *tty); 514 extern void deinitialize_tty_struct(struct tty_struct *tty); 515 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 516 extern int tty_release(struct inode *inode, struct file *filp); 517 extern int tty_init_termios(struct tty_struct *tty); 518 extern int tty_standard_install(struct tty_driver *driver, 519 struct tty_struct *tty); 520 521 extern struct mutex tty_mutex; 522 extern spinlock_t tty_files_lock; 523 524 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 525 526 extern void tty_port_init(struct tty_port *port); 527 extern void tty_port_link_device(struct tty_port *port, 528 struct tty_driver *driver, unsigned index); 529 extern struct device *tty_port_register_device(struct tty_port *port, 530 struct tty_driver *driver, unsigned index, 531 struct device *device); 532 extern struct device *tty_port_register_device_attr(struct tty_port *port, 533 struct tty_driver *driver, unsigned index, 534 struct device *device, void *drvdata, 535 const struct attribute_group **attr_grp); 536 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 537 extern void tty_port_free_xmit_buf(struct tty_port *port); 538 extern void tty_port_destroy(struct tty_port *port); 539 extern void tty_port_put(struct tty_port *port); 540 541 static inline struct tty_port *tty_port_get(struct tty_port *port) 542 { 543 if (port && kref_get_unless_zero(&port->kref)) 544 return port; 545 return NULL; 546 } 547 548 /* If the cts flow control is enabled, return true. */ 549 static inline bool tty_port_cts_enabled(struct tty_port *port) 550 { 551 return port->flags & ASYNC_CTS_FLOW; 552 } 553 554 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 555 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 556 extern int tty_port_carrier_raised(struct tty_port *port); 557 extern void tty_port_raise_dtr_rts(struct tty_port *port); 558 extern void tty_port_lower_dtr_rts(struct tty_port *port); 559 extern void tty_port_hangup(struct tty_port *port); 560 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 561 extern void tty_port_tty_wakeup(struct tty_port *port); 562 extern int tty_port_block_til_ready(struct tty_port *port, 563 struct tty_struct *tty, struct file *filp); 564 extern int tty_port_close_start(struct tty_port *port, 565 struct tty_struct *tty, struct file *filp); 566 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 567 extern void tty_port_close(struct tty_port *port, 568 struct tty_struct *tty, struct file *filp); 569 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 570 struct tty_struct *tty); 571 extern int tty_port_open(struct tty_port *port, 572 struct tty_struct *tty, struct file *filp); 573 static inline int tty_port_users(struct tty_port *port) 574 { 575 return port->count + port->blocked_open; 576 } 577 578 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 579 extern int tty_unregister_ldisc(int disc); 580 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 581 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 582 extern void tty_ldisc_release(struct tty_struct *tty); 583 extern void tty_ldisc_init(struct tty_struct *tty); 584 extern void tty_ldisc_deinit(struct tty_struct *tty); 585 extern void tty_ldisc_begin(void); 586 587 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 588 char *f, int count) 589 { 590 if (ld->ops->receive_buf2) 591 count = ld->ops->receive_buf2(ld->tty, p, f, count); 592 else { 593 count = min_t(int, count, ld->tty->receive_room); 594 if (count) 595 ld->ops->receive_buf(ld->tty, p, f, count); 596 } 597 return count; 598 } 599 600 601 /* n_tty.c */ 602 extern struct tty_ldisc_ops tty_ldisc_N_TTY; 603 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 604 605 /* tty_audit.c */ 606 #ifdef CONFIG_AUDIT 607 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 608 size_t size, unsigned icanon); 609 extern void tty_audit_exit(void); 610 extern void tty_audit_fork(struct signal_struct *sig); 611 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 612 extern void tty_audit_push(struct tty_struct *tty); 613 extern int tty_audit_push_current(void); 614 #else 615 static inline void tty_audit_add_data(struct tty_struct *tty, 616 unsigned char *data, size_t size, unsigned icanon) 617 { 618 } 619 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 620 { 621 } 622 static inline void tty_audit_exit(void) 623 { 624 } 625 static inline void tty_audit_fork(struct signal_struct *sig) 626 { 627 } 628 static inline void tty_audit_push(struct tty_struct *tty) 629 { 630 } 631 static inline int tty_audit_push_current(void) 632 { 633 return 0; 634 } 635 #endif 636 637 /* tty_ioctl.c */ 638 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 639 unsigned int cmd, unsigned long arg); 640 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 641 unsigned int cmd, unsigned long arg); 642 643 /* vt.c */ 644 645 extern int vt_ioctl(struct tty_struct *tty, 646 unsigned int cmd, unsigned long arg); 647 648 extern long vt_compat_ioctl(struct tty_struct *tty, 649 unsigned int cmd, unsigned long arg); 650 651 /* tty_mutex.c */ 652 /* functions for preparation of BKL removal */ 653 extern void __lockfunc tty_lock(struct tty_struct *tty); 654 extern void __lockfunc tty_unlock(struct tty_struct *tty); 655 extern void __lockfunc tty_lock_slave(struct tty_struct *tty); 656 extern void __lockfunc tty_unlock_slave(struct tty_struct *tty); 657 extern void tty_set_lock_subclass(struct tty_struct *tty); 658 /* 659 * this shall be called only from where BTM is held (like close) 660 * 661 * We need this to ensure nobody waits for us to finish while we are waiting. 662 * Without this we were encountering system stalls. 663 * 664 * This should be indeed removed with BTM removal later. 665 * 666 * Locking: BTM required. Nobody is allowed to hold port->mutex. 667 */ 668 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 669 long timeout) 670 { 671 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 672 tty_wait_until_sent(tty, timeout); 673 tty_lock(tty); 674 } 675 676 /* 677 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 678 * 679 * The condition we are waiting for might take a long time to 680 * become true, or might depend on another thread taking the 681 * BTM. In either case, we need to drop the BTM to guarantee 682 * forward progress. This is a leftover from the conversion 683 * from the BKL and should eventually get removed as the BTM 684 * falls out of use. 685 * 686 * Do not use in new code. 687 */ 688 #define wait_event_interruptible_tty(tty, wq, condition) \ 689 ({ \ 690 int __ret = 0; \ 691 if (!(condition)) \ 692 __ret = __wait_event_interruptible_tty(tty, wq, \ 693 condition); \ 694 __ret; \ 695 }) 696 697 #define __wait_event_interruptible_tty(tty, wq, condition) \ 698 ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ 699 tty_unlock(tty); \ 700 schedule(); \ 701 tty_lock(tty)) 702 703 #ifdef CONFIG_PROC_FS 704 extern void proc_tty_register_driver(struct tty_driver *); 705 extern void proc_tty_unregister_driver(struct tty_driver *); 706 #else 707 static inline void proc_tty_register_driver(struct tty_driver *d) {} 708 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 709 #endif 710 711 #endif 712