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 delta_msr_wait; /* Modem status change */ 231 unsigned long flags; /* TTY flags ASY_*/ 232 unsigned char console:1, /* port is a console */ 233 low_latency:1; /* optional: tune for latency */ 234 struct mutex mutex; /* Locking */ 235 struct mutex buf_mutex; /* Buffer alloc lock */ 236 unsigned char *xmit_buf; /* Optional buffer */ 237 unsigned int close_delay; /* Close port delay */ 238 unsigned int closing_wait; /* Delay for output */ 239 int drain_delay; /* Set to zero if no pure time 240 based drain is needed else 241 set to size of fifo */ 242 struct kref kref; /* Ref counter */ 243 }; 244 245 /* 246 * Where all of the state associated with a tty is kept while the tty 247 * is open. Since the termios state should be kept even if the tty 248 * has been closed --- for things like the baud rate, etc --- it is 249 * not stored here, but rather a pointer to the real state is stored 250 * here. Possible the winsize structure should have the same 251 * treatment, but (1) the default 80x24 is usually right and (2) it's 252 * most often used by a windowing system, which will set the correct 253 * size each time the window is created or resized anyway. 254 * - TYT, 9/14/92 255 */ 256 257 struct tty_operations; 258 259 struct tty_struct { 260 int magic; 261 struct kref kref; 262 struct device *dev; 263 struct tty_driver *driver; 264 const struct tty_operations *ops; 265 int index; 266 267 /* Protects ldisc changes: Lock tty not pty */ 268 struct ld_semaphore ldisc_sem; 269 struct tty_ldisc *ldisc; 270 271 struct mutex atomic_write_lock; 272 struct mutex legacy_mutex; 273 struct mutex throttle_mutex; 274 struct rw_semaphore termios_rwsem; 275 struct mutex winsize_mutex; 276 spinlock_t ctrl_lock; 277 spinlock_t flow_lock; 278 /* Termios values are protected by the termios rwsem */ 279 struct ktermios termios, termios_locked; 280 struct termiox *termiox; /* May be NULL for unsupported */ 281 char name[64]; 282 struct pid *pgrp; /* Protected by ctrl lock */ 283 struct pid *session; 284 unsigned long flags; 285 int count; 286 struct winsize winsize; /* winsize_mutex */ 287 unsigned long stopped:1, /* flow_lock */ 288 flow_stopped:1, 289 unused:BITS_PER_LONG - 2; 290 int hw_stopped; 291 unsigned long ctrl_status:8, /* ctrl_lock */ 292 packet:1, 293 unused_ctrl:BITS_PER_LONG - 9; 294 unsigned int receive_room; /* Bytes free for queue */ 295 int flow_change; 296 297 struct tty_struct *link; 298 struct fasync_struct *fasync; 299 int alt_speed; /* For magic substitution of 38400 bps */ 300 wait_queue_head_t write_wait; 301 wait_queue_head_t read_wait; 302 struct work_struct hangup_work; 303 void *disc_data; 304 void *driver_data; 305 struct list_head tty_files; 306 307 #define N_TTY_BUF_SIZE 4096 308 309 int closing; 310 unsigned char *write_buf; 311 int write_cnt; 312 /* If the tty has a pending do_SAK, queue it here - akpm */ 313 struct work_struct SAK_work; 314 struct tty_port *port; 315 }; 316 317 /* Each of a tty's open files has private_data pointing to tty_file_private */ 318 struct tty_file_private { 319 struct tty_struct *tty; 320 struct file *file; 321 struct list_head list; 322 }; 323 324 /* tty magic number */ 325 #define TTY_MAGIC 0x5401 326 327 /* 328 * These bits are used in the flags field of the tty structure. 329 * 330 * So that interrupts won't be able to mess up the queues, 331 * copy_to_cooked must be atomic with respect to itself, as must 332 * tty->write. Thus, you must use the inline functions set_bit() and 333 * clear_bit() to make things atomic. 334 */ 335 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 336 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 337 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 338 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 339 #define TTY_DEBUG 4 /* Debugging */ 340 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 341 #define TTY_OTHER_DONE 6 /* Closed pty has completed input processing */ 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 /* Values for tty->flow_change */ 349 #define TTY_THROTTLE_SAFE 1 350 #define TTY_UNTHROTTLE_SAFE 2 351 352 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 353 { 354 tty->flow_change = val; 355 } 356 357 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 358 { 359 tty->flow_change = val; 360 smp_mb(); 361 } 362 363 #ifdef CONFIG_TTY 364 extern void console_init(void); 365 extern void tty_kref_put(struct tty_struct *tty); 366 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 367 extern void tty_vhangup_self(void); 368 extern void disassociate_ctty(int priv); 369 extern dev_t tty_devnum(struct tty_struct *tty); 370 extern void proc_clear_tty(struct task_struct *p); 371 extern struct tty_struct *get_current_tty(void); 372 /* tty_io.c */ 373 extern int __init tty_init(void); 374 #else 375 static inline void console_init(void) 376 { } 377 static inline void tty_kref_put(struct tty_struct *tty) 378 { } 379 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 380 { return NULL; } 381 static inline void tty_vhangup_self(void) 382 { } 383 static inline void disassociate_ctty(int priv) 384 { } 385 static inline dev_t tty_devnum(struct tty_struct *tty) 386 { return 0; } 387 static inline void proc_clear_tty(struct task_struct *p) 388 { } 389 static inline struct tty_struct *get_current_tty(void) 390 { return NULL; } 391 /* tty_io.c */ 392 static inline int __init tty_init(void) 393 { return 0; } 394 #endif 395 396 extern struct ktermios tty_std_termios; 397 398 extern int vcs_init(void); 399 400 extern struct class *tty_class; 401 402 /** 403 * tty_kref_get - get a tty reference 404 * @tty: tty device 405 * 406 * Return a new reference to a tty object. The caller must hold 407 * sufficient locks/counts to ensure that their existing reference cannot 408 * go away 409 */ 410 411 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 412 { 413 if (tty) 414 kref_get(&tty->kref); 415 return tty; 416 } 417 418 extern const char *tty_name(const struct tty_struct *tty); 419 extern const char *tty_driver_name(const struct tty_struct *tty); 420 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 421 extern int __tty_check_change(struct tty_struct *tty, int sig); 422 extern int tty_check_change(struct tty_struct *tty); 423 extern void __stop_tty(struct tty_struct *tty); 424 extern void stop_tty(struct tty_struct *tty); 425 extern void __start_tty(struct tty_struct *tty); 426 extern void start_tty(struct tty_struct *tty); 427 extern int tty_register_driver(struct tty_driver *driver); 428 extern int tty_unregister_driver(struct tty_driver *driver); 429 extern struct device *tty_register_device(struct tty_driver *driver, 430 unsigned index, struct device *dev); 431 extern struct device *tty_register_device_attr(struct tty_driver *driver, 432 unsigned index, struct device *device, 433 void *drvdata, 434 const struct attribute_group **attr_grp); 435 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 436 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 437 int buflen); 438 extern void tty_write_message(struct tty_struct *tty, char *msg); 439 extern int tty_send_xchar(struct tty_struct *tty, char ch); 440 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 441 extern int tty_chars_in_buffer(struct tty_struct *tty); 442 extern int tty_write_room(struct tty_struct *tty); 443 extern void tty_driver_flush_buffer(struct tty_struct *tty); 444 extern void tty_throttle(struct tty_struct *tty); 445 extern void tty_unthrottle(struct tty_struct *tty); 446 extern int tty_throttle_safe(struct tty_struct *tty); 447 extern int tty_unthrottle_safe(struct tty_struct *tty); 448 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 449 extern void tty_driver_remove_tty(struct tty_driver *driver, 450 struct tty_struct *tty); 451 extern void tty_free_termios(struct tty_struct *tty); 452 extern int is_current_pgrp_orphaned(void); 453 extern int is_ignored(int sig); 454 extern int tty_signal(int sig, struct tty_struct *tty); 455 extern void tty_hangup(struct tty_struct *tty); 456 extern void tty_vhangup(struct tty_struct *tty); 457 extern int tty_hung_up_p(struct file *filp); 458 extern void do_SAK(struct tty_struct *tty); 459 extern void __do_SAK(struct tty_struct *tty); 460 extern void no_tty(void); 461 extern void tty_buffer_free_all(struct tty_port *port); 462 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 463 extern void tty_buffer_init(struct tty_port *port); 464 extern void tty_buffer_set_lock_subclass(struct tty_port *port); 465 extern bool tty_buffer_restart_work(struct tty_port *port); 466 extern bool tty_buffer_cancel_work(struct tty_port *port); 467 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 468 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 469 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 470 speed_t ibaud, speed_t obaud); 471 extern void tty_encode_baud_rate(struct tty_struct *tty, 472 speed_t ibaud, speed_t obaud); 473 474 /** 475 * tty_get_baud_rate - get tty bit rates 476 * @tty: tty to query 477 * 478 * Returns the baud rate as an integer for this terminal. The 479 * termios lock must be held by the caller and the terminal bit 480 * flags may be updated. 481 * 482 * Locking: none 483 */ 484 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 485 { 486 return tty_termios_baud_rate(&tty->termios); 487 } 488 489 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 490 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 491 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 492 493 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 494 extern void tty_ldisc_deref(struct tty_ldisc *); 495 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 496 extern void tty_ldisc_hangup(struct tty_struct *tty); 497 extern const struct file_operations tty_ldiscs_proc_fops; 498 499 extern void tty_wakeup(struct tty_struct *tty); 500 extern void tty_ldisc_flush(struct tty_struct *tty); 501 502 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 503 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 504 unsigned int cmd, unsigned long arg); 505 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 506 extern void tty_default_fops(struct file_operations *fops); 507 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 508 extern int tty_alloc_file(struct file *file); 509 extern void tty_add_file(struct tty_struct *tty, struct file *file); 510 extern void tty_free_file(struct file *file); 511 extern void free_tty_struct(struct tty_struct *tty); 512 extern void deinitialize_tty_struct(struct tty_struct *tty); 513 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 514 extern int tty_release(struct inode *inode, struct file *filp); 515 extern int tty_init_termios(struct tty_struct *tty); 516 extern int tty_standard_install(struct tty_driver *driver, 517 struct tty_struct *tty); 518 519 extern struct mutex tty_mutex; 520 extern spinlock_t tty_files_lock; 521 522 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 523 524 extern void tty_port_init(struct tty_port *port); 525 extern void tty_port_link_device(struct tty_port *port, 526 struct tty_driver *driver, unsigned index); 527 extern struct device *tty_port_register_device(struct tty_port *port, 528 struct tty_driver *driver, unsigned index, 529 struct device *device); 530 extern struct device *tty_port_register_device_attr(struct tty_port *port, 531 struct tty_driver *driver, unsigned index, 532 struct device *device, void *drvdata, 533 const struct attribute_group **attr_grp); 534 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 535 extern void tty_port_free_xmit_buf(struct tty_port *port); 536 extern void tty_port_destroy(struct tty_port *port); 537 extern void tty_port_put(struct tty_port *port); 538 539 static inline struct tty_port *tty_port_get(struct tty_port *port) 540 { 541 if (port && kref_get_unless_zero(&port->kref)) 542 return port; 543 return NULL; 544 } 545 546 /* If the cts flow control is enabled, return true. */ 547 static inline bool tty_port_cts_enabled(struct tty_port *port) 548 { 549 return port->flags & ASYNC_CTS_FLOW; 550 } 551 552 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 553 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 554 extern int tty_port_carrier_raised(struct tty_port *port); 555 extern void tty_port_raise_dtr_rts(struct tty_port *port); 556 extern void tty_port_lower_dtr_rts(struct tty_port *port); 557 extern void tty_port_hangup(struct tty_port *port); 558 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 559 extern void tty_port_tty_wakeup(struct tty_port *port); 560 extern int tty_port_block_til_ready(struct tty_port *port, 561 struct tty_struct *tty, struct file *filp); 562 extern int tty_port_close_start(struct tty_port *port, 563 struct tty_struct *tty, struct file *filp); 564 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 565 extern void tty_port_close(struct tty_port *port, 566 struct tty_struct *tty, struct file *filp); 567 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 568 struct tty_struct *tty); 569 extern int tty_port_open(struct tty_port *port, 570 struct tty_struct *tty, struct file *filp); 571 static inline int tty_port_users(struct tty_port *port) 572 { 573 return port->count + port->blocked_open; 574 } 575 576 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 577 extern int tty_unregister_ldisc(int disc); 578 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 579 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 580 extern void tty_ldisc_release(struct tty_struct *tty); 581 extern void tty_ldisc_init(struct tty_struct *tty); 582 extern void tty_ldisc_deinit(struct tty_struct *tty); 583 extern void tty_ldisc_begin(void); 584 585 static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 586 char *f, int count) 587 { 588 if (ld->ops->receive_buf2) 589 count = ld->ops->receive_buf2(ld->tty, p, f, count); 590 else { 591 count = min_t(int, count, ld->tty->receive_room); 592 if (count) 593 ld->ops->receive_buf(ld->tty, p, f, count); 594 } 595 return count; 596 } 597 598 599 /* n_tty.c */ 600 extern struct tty_ldisc_ops tty_ldisc_N_TTY; 601 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 602 603 /* tty_audit.c */ 604 #ifdef CONFIG_AUDIT 605 extern void tty_audit_add_data(struct tty_struct *tty, const void *data, 606 size_t size, unsigned icanon); 607 extern void tty_audit_exit(void); 608 extern void tty_audit_fork(struct signal_struct *sig); 609 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 610 extern void tty_audit_push(struct tty_struct *tty); 611 extern int tty_audit_push_current(void); 612 #else 613 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data, 614 size_t size, unsigned icanon) 615 { 616 } 617 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 618 { 619 } 620 static inline void tty_audit_exit(void) 621 { 622 } 623 static inline void tty_audit_fork(struct signal_struct *sig) 624 { 625 } 626 static inline void tty_audit_push(struct tty_struct *tty) 627 { 628 } 629 static inline int tty_audit_push_current(void) 630 { 631 return 0; 632 } 633 #endif 634 635 /* tty_ioctl.c */ 636 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 637 unsigned int cmd, unsigned long arg); 638 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 639 unsigned int cmd, unsigned long arg); 640 641 /* vt.c */ 642 643 extern int vt_ioctl(struct tty_struct *tty, 644 unsigned int cmd, unsigned long arg); 645 646 extern long vt_compat_ioctl(struct tty_struct *tty, 647 unsigned int cmd, unsigned long arg); 648 649 /* tty_mutex.c */ 650 /* functions for preparation of BKL removal */ 651 extern void __lockfunc tty_lock(struct tty_struct *tty); 652 extern void __lockfunc tty_unlock(struct tty_struct *tty); 653 extern void __lockfunc tty_lock_slave(struct tty_struct *tty); 654 extern void __lockfunc tty_unlock_slave(struct tty_struct *tty); 655 extern void tty_set_lock_subclass(struct tty_struct *tty); 656 657 #ifdef CONFIG_PROC_FS 658 extern void proc_tty_register_driver(struct tty_driver *); 659 extern void proc_tty_unregister_driver(struct tty_driver *); 660 #else 661 static inline void proc_tty_register_driver(struct tty_driver *d) {} 662 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 663 #endif 664 665 #define tty_msg(fn, tty, f, ...) \ 666 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) 667 668 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) 669 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__) 670 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) 671 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) 672 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) 673 674 #define tty_info_ratelimited(tty, f, ...) \ 675 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) 676 677 #endif 678