1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_TTY_H 3 #define _LINUX_TTY_H 4 5 #include <linux/fs.h> 6 #include <linux/major.h> 7 #include <linux/termios.h> 8 #include <linux/workqueue.h> 9 #include <linux/tty_driver.h> 10 #include <linux/tty_ldisc.h> 11 #include <linux/mutex.h> 12 #include <linux/tty_flags.h> 13 #include <linux/seq_file.h> 14 #include <uapi/linux/tty.h> 15 #include <linux/rwsem.h> 16 #include <linux/llist.h> 17 18 19 /* 20 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 21 * hardcoded at present.) 22 */ 23 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 24 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 25 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 26 27 /* 28 * This character is the same as _POSIX_VDISABLE: it cannot be used as 29 * a c_cc[] character, but indicates that a particular special character 30 * isn't in use (eg VINTR has no character etc) 31 */ 32 #define __DISABLED_CHAR '\0' 33 34 struct tty_buffer { 35 union { 36 struct tty_buffer *next; 37 struct llist_node free; 38 }; 39 int used; 40 int size; 41 int commit; 42 int read; 43 int flags; 44 /* Data points here */ 45 unsigned long data[]; 46 }; 47 48 /* Values for .flags field of tty_buffer */ 49 #define TTYB_NORMAL 1 /* buffer has no flags buffer */ 50 51 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 52 { 53 return ((unsigned char *)b->data) + ofs; 54 } 55 56 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 57 { 58 return (char *)char_buf_ptr(b, ofs) + b->size; 59 } 60 61 struct tty_bufhead { 62 struct tty_buffer *head; /* Queue head */ 63 struct work_struct work; 64 struct mutex lock; 65 atomic_t priority; 66 struct tty_buffer sentinel; 67 struct llist_head free; /* Free queue head */ 68 atomic_t mem_used; /* In-use buffers excluding free list */ 69 int mem_limit; 70 struct tty_buffer *tail; /* Active buffer */ 71 }; 72 /* 73 * When a break, frame error, or parity error happens, these codes are 74 * stuffed into the flags buffer. 75 */ 76 #define TTY_NORMAL 0 77 #define TTY_BREAK 1 78 #define TTY_FRAME 2 79 #define TTY_PARITY 3 80 #define TTY_OVERRUN 4 81 82 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 83 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 84 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 85 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 86 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 87 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 88 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 89 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 90 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 91 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 92 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 93 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 94 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 95 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 96 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 97 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 98 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 99 100 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 101 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 102 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 103 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 104 105 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 106 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 107 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 108 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 109 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 110 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 111 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 112 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 113 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 114 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 115 #define I_IXON(tty) _I_FLAG((tty), IXON) 116 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 117 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 118 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 119 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 120 121 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 122 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 123 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 124 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 125 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 126 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 127 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 128 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 129 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 130 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 131 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 132 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 133 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 134 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 135 136 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 137 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 138 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 139 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 140 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 141 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 142 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 143 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 144 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 145 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 146 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 147 148 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 149 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 150 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 151 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 152 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 153 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 154 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 155 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 156 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 157 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 158 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 159 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 160 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 161 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 162 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 163 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 164 165 struct device; 166 struct signal_struct; 167 168 /* 169 * Port level information. Each device keeps its own port level information 170 * so provide a common structure for those ports wanting to use common support 171 * routines. 172 * 173 * The tty port has a different lifetime to the tty so must be kept apart. 174 * In addition be careful as tty -> port mappings are valid for the life 175 * of the tty object but in many cases port -> tty mappings are valid only 176 * until a hangup so don't use the wrong path. 177 */ 178 179 struct tty_port; 180 181 struct tty_port_operations { 182 /* Return 1 if the carrier is raised */ 183 int (*carrier_raised)(struct tty_port *port); 184 /* Control the DTR line */ 185 void (*dtr_rts)(struct tty_port *port, int raise); 186 /* Called when the last close completes or a hangup finishes 187 IFF the port was initialized. Do not use to free resources. Called 188 under the port mutex to serialize against activate/shutdowns */ 189 void (*shutdown)(struct tty_port *port); 190 /* Called under the port mutex from tty_port_open, serialized using 191 the port mutex */ 192 /* FIXME: long term getting the tty argument *out* of this would be 193 good for consoles */ 194 int (*activate)(struct tty_port *port, struct tty_struct *tty); 195 /* Called on the final put of a port */ 196 void (*destruct)(struct tty_port *port); 197 }; 198 199 struct tty_port_client_operations { 200 int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t); 201 void (*write_wakeup)(struct tty_port *port); 202 }; 203 204 extern const struct tty_port_client_operations tty_port_default_client_ops; 205 206 struct tty_port { 207 struct tty_bufhead buf; /* Locked internally */ 208 struct tty_struct *tty; /* Back pointer */ 209 struct tty_struct *itty; /* internal back ptr */ 210 const struct tty_port_operations *ops; /* Port operations */ 211 const struct tty_port_client_operations *client_ops; /* Port client operations */ 212 spinlock_t lock; /* Lock protecting tty field */ 213 int blocked_open; /* Waiting to open */ 214 int count; /* Usage count */ 215 wait_queue_head_t open_wait; /* Open waiters */ 216 wait_queue_head_t delta_msr_wait; /* Modem status change */ 217 unsigned long flags; /* User TTY flags ASYNC_ */ 218 unsigned long iflags; /* Internal flags TTY_PORT_ */ 219 unsigned char console:1; /* port is a console */ 220 struct mutex mutex; /* Locking */ 221 struct mutex buf_mutex; /* Buffer alloc lock */ 222 unsigned char *xmit_buf; /* Optional buffer */ 223 unsigned int close_delay; /* Close port delay */ 224 unsigned int closing_wait; /* Delay for output */ 225 int drain_delay; /* Set to zero if no pure time 226 based drain is needed else 227 set to size of fifo */ 228 struct kref kref; /* Ref counter */ 229 void *client_data; 230 }; 231 232 /* tty_port::iflags bits -- use atomic bit ops */ 233 #define TTY_PORT_INITIALIZED 0 /* device is initialized */ 234 #define TTY_PORT_SUSPENDED 1 /* device is suspended */ 235 #define TTY_PORT_ACTIVE 2 /* device is open */ 236 237 /* 238 * uart drivers: use the uart_port::status field and the UPSTAT_* defines 239 * for s/w-based flow control steering and carrier detection status 240 */ 241 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */ 242 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */ 243 #define TTY_PORT_KOPENED 5 /* device exclusively opened by 244 kernel */ 245 246 struct tty_operations; 247 248 /** 249 * struct tty_struct - state associated with a tty while open 250 * 251 * @flow.lock: lock for flow members 252 * @flow.stopped: tty stopped/started by tty_stop/tty_start 253 * @flow.tco_stopped: tty stopped/started by TCOOFF/TCOON ioctls (it has 254 * precedense over @flow.stopped) 255 * @flow.unused: alignment for Alpha, so that no members other than @flow.* are 256 * modified by the same 64b word store. The @flow's __aligned is 257 * there for the very same reason. 258 * @ctrl.lock: lock for ctrl members 259 * @ctrl.pgrp: process group of this tty (setpgrp(2)) 260 * @ctrl.session: session of this tty (setsid(2)). Writes are protected by both 261 * @ctrl.lock and legacy mutex, readers must use at least one of 262 * them. 263 * @ctrl.pktstatus: packet mode status (bitwise OR of TIOCPKT_* constants) 264 * @ctrl.packet: packet mode enabled 265 * 266 * All of the state associated with a tty while the tty is open. Persistent 267 * storage for tty devices is referenced here as @port in struct tty_port. 268 */ 269 struct tty_struct { 270 int magic; 271 struct kref kref; 272 struct device *dev; /* class device or NULL (e.g. ptys, serdev) */ 273 struct tty_driver *driver; 274 const struct tty_operations *ops; 275 int index; 276 277 /* Protects ldisc changes: Lock tty not pty */ 278 struct ld_semaphore ldisc_sem; 279 struct tty_ldisc *ldisc; 280 281 struct mutex atomic_write_lock; 282 struct mutex legacy_mutex; 283 struct mutex throttle_mutex; 284 struct rw_semaphore termios_rwsem; 285 struct mutex winsize_mutex; 286 /* Termios values are protected by the termios rwsem */ 287 struct ktermios termios, termios_locked; 288 char name[64]; 289 unsigned long flags; 290 int count; 291 struct winsize winsize; /* winsize_mutex */ 292 293 struct { 294 spinlock_t lock; 295 bool stopped; 296 bool tco_stopped; 297 unsigned long unused[0]; 298 } __aligned(sizeof(unsigned long)) flow; 299 300 struct { 301 spinlock_t lock; 302 struct pid *pgrp; 303 struct pid *session; 304 unsigned char pktstatus; 305 bool packet; 306 unsigned long unused[0]; 307 } __aligned(sizeof(unsigned long)) ctrl; 308 309 int hw_stopped; 310 unsigned int receive_room; /* Bytes free for queue */ 311 int flow_change; 312 313 struct tty_struct *link; 314 struct fasync_struct *fasync; 315 wait_queue_head_t write_wait; 316 wait_queue_head_t read_wait; 317 struct work_struct hangup_work; 318 void *disc_data; 319 void *driver_data; 320 spinlock_t files_lock; /* protects tty_files list */ 321 struct list_head tty_files; 322 323 #define N_TTY_BUF_SIZE 4096 324 325 int closing; 326 unsigned char *write_buf; 327 int write_cnt; 328 /* If the tty has a pending do_SAK, queue it here - akpm */ 329 struct work_struct SAK_work; 330 struct tty_port *port; 331 } __randomize_layout; 332 333 /* Each of a tty's open files has private_data pointing to tty_file_private */ 334 struct tty_file_private { 335 struct tty_struct *tty; 336 struct file *file; 337 struct list_head list; 338 }; 339 340 /* tty magic number */ 341 #define TTY_MAGIC 0x5401 342 343 /* 344 * These bits are used in the flags field of the tty structure. 345 * 346 * So that interrupts won't be able to mess up the queues, 347 * copy_to_cooked must be atomic with respect to itself, as must 348 * tty->write. Thus, you must use the inline functions set_bit() and 349 * clear_bit() to make things atomic. 350 */ 351 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 352 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 353 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 354 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 355 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 356 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 357 #define TTY_PTY_LOCK 16 /* pty private */ 358 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 359 #define TTY_HUPPED 18 /* Post driver->hangup() */ 360 #define TTY_HUPPING 19 /* Hangup in progress */ 361 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */ 362 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 363 364 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file) 365 { 366 return file->f_flags & O_NONBLOCK || 367 test_bit(TTY_LDISC_CHANGING, &tty->flags); 368 } 369 370 static inline bool tty_io_error(struct tty_struct *tty) 371 { 372 return test_bit(TTY_IO_ERROR, &tty->flags); 373 } 374 375 static inline bool tty_throttled(struct tty_struct *tty) 376 { 377 return test_bit(TTY_THROTTLED, &tty->flags); 378 } 379 380 #ifdef CONFIG_TTY 381 extern void tty_kref_put(struct tty_struct *tty); 382 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 383 extern void tty_vhangup_self(void); 384 extern void disassociate_ctty(int priv); 385 extern dev_t tty_devnum(struct tty_struct *tty); 386 extern void proc_clear_tty(struct task_struct *p); 387 extern struct tty_struct *get_current_tty(void); 388 /* tty_io.c */ 389 extern int __init tty_init(void); 390 extern const char *tty_name(const struct tty_struct *tty); 391 extern struct tty_struct *tty_kopen_exclusive(dev_t device); 392 extern struct tty_struct *tty_kopen_shared(dev_t device); 393 extern void tty_kclose(struct tty_struct *tty); 394 extern int tty_dev_name_to_number(const char *name, dev_t *number); 395 #else 396 static inline void tty_kref_put(struct tty_struct *tty) 397 { } 398 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 399 { return NULL; } 400 static inline void tty_vhangup_self(void) 401 { } 402 static inline void disassociate_ctty(int priv) 403 { } 404 static inline dev_t tty_devnum(struct tty_struct *tty) 405 { return 0; } 406 static inline void proc_clear_tty(struct task_struct *p) 407 { } 408 static inline struct tty_struct *get_current_tty(void) 409 { return NULL; } 410 /* tty_io.c */ 411 static inline int __init tty_init(void) 412 { return 0; } 413 static inline const char *tty_name(const struct tty_struct *tty) 414 { return "(none)"; } 415 static inline struct tty_struct *tty_kopen_exclusive(dev_t device) 416 { return ERR_PTR(-ENODEV); } 417 static inline void tty_kclose(struct tty_struct *tty) 418 { } 419 static inline int tty_dev_name_to_number(const char *name, dev_t *number) 420 { return -ENOTSUPP; } 421 #endif 422 423 extern struct ktermios tty_std_termios; 424 425 extern int vcs_init(void); 426 427 extern struct class *tty_class; 428 429 /** 430 * tty_kref_get - get a tty reference 431 * @tty: tty device 432 * 433 * Return a new reference to a tty object. The caller must hold 434 * sufficient locks/counts to ensure that their existing reference cannot 435 * go away 436 */ 437 438 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 439 { 440 if (tty) 441 kref_get(&tty->kref); 442 return tty; 443 } 444 445 extern const char *tty_driver_name(const struct tty_struct *tty); 446 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 447 extern void stop_tty(struct tty_struct *tty); 448 extern void start_tty(struct tty_struct *tty); 449 extern int tty_register_driver(struct tty_driver *driver); 450 extern void tty_unregister_driver(struct tty_driver *driver); 451 extern struct device *tty_register_device(struct tty_driver *driver, 452 unsigned index, struct device *dev); 453 extern struct device *tty_register_device_attr(struct tty_driver *driver, 454 unsigned index, struct device *device, 455 void *drvdata, 456 const struct attribute_group **attr_grp); 457 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 458 extern void tty_write_message(struct tty_struct *tty, char *msg); 459 extern int tty_send_xchar(struct tty_struct *tty, char ch); 460 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 461 extern unsigned int tty_chars_in_buffer(struct tty_struct *tty); 462 extern unsigned int tty_write_room(struct tty_struct *tty); 463 extern void tty_driver_flush_buffer(struct tty_struct *tty); 464 extern void tty_unthrottle(struct tty_struct *tty); 465 extern int tty_throttle_safe(struct tty_struct *tty); 466 extern int tty_unthrottle_safe(struct tty_struct *tty); 467 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 468 extern int tty_get_icount(struct tty_struct *tty, 469 struct serial_icounter_struct *icount); 470 extern int is_current_pgrp_orphaned(void); 471 extern void tty_hangup(struct tty_struct *tty); 472 extern void tty_vhangup(struct tty_struct *tty); 473 extern int tty_hung_up_p(struct file *filp); 474 extern void do_SAK(struct tty_struct *tty); 475 extern void __do_SAK(struct tty_struct *tty); 476 extern void no_tty(void); 477 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 478 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 479 speed_t ibaud, speed_t obaud); 480 extern void tty_encode_baud_rate(struct tty_struct *tty, 481 speed_t ibaud, speed_t obaud); 482 483 /** 484 * tty_get_baud_rate - get tty bit rates 485 * @tty: tty to query 486 * 487 * Returns the baud rate as an integer for this terminal. The 488 * termios lock must be held by the caller and the terminal bit 489 * flags may be updated. 490 * 491 * Locking: none 492 */ 493 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 494 { 495 return tty_termios_baud_rate(&tty->termios); 496 } 497 498 unsigned char tty_get_char_size(unsigned int cflag); 499 unsigned char tty_get_frame_size(unsigned int cflag); 500 501 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 502 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); 503 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 504 505 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 506 extern void tty_ldisc_deref(struct tty_ldisc *); 507 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 508 extern const struct seq_operations tty_ldiscs_seq_ops; 509 510 extern void tty_wakeup(struct tty_struct *tty); 511 extern void tty_ldisc_flush(struct tty_struct *tty); 512 513 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 514 unsigned int cmd, unsigned long arg); 515 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 516 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 517 extern void tty_release_struct(struct tty_struct *tty, int idx); 518 extern void tty_init_termios(struct tty_struct *tty); 519 extern void tty_save_termios(struct tty_struct *tty); 520 extern int tty_standard_install(struct tty_driver *driver, 521 struct tty_struct *tty); 522 523 extern struct mutex tty_mutex; 524 525 extern void tty_port_init(struct tty_port *port); 526 extern void tty_port_link_device(struct tty_port *port, 527 struct tty_driver *driver, unsigned index); 528 extern struct device *tty_port_register_device(struct tty_port *port, 529 struct tty_driver *driver, unsigned index, 530 struct device *device); 531 extern struct device *tty_port_register_device_attr(struct tty_port *port, 532 struct tty_driver *driver, unsigned index, 533 struct device *device, void *drvdata, 534 const struct attribute_group **attr_grp); 535 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 536 struct tty_driver *driver, unsigned index, 537 struct device *device); 538 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 539 struct tty_driver *driver, unsigned index, 540 struct device *device, void *drvdata, 541 const struct attribute_group **attr_grp); 542 extern void tty_port_unregister_device(struct tty_port *port, 543 struct tty_driver *driver, unsigned index); 544 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 545 extern void tty_port_free_xmit_buf(struct tty_port *port); 546 extern void tty_port_destroy(struct tty_port *port); 547 extern void tty_port_put(struct tty_port *port); 548 549 static inline struct tty_port *tty_port_get(struct tty_port *port) 550 { 551 if (port && kref_get_unless_zero(&port->kref)) 552 return port; 553 return NULL; 554 } 555 556 /* If the cts flow control is enabled, return true. */ 557 static inline bool tty_port_cts_enabled(const struct tty_port *port) 558 { 559 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 560 } 561 562 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 563 { 564 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val); 565 } 566 567 static inline bool tty_port_active(const struct tty_port *port) 568 { 569 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 570 } 571 572 static inline void tty_port_set_active(struct tty_port *port, bool val) 573 { 574 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val); 575 } 576 577 static inline bool tty_port_check_carrier(const struct tty_port *port) 578 { 579 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 580 } 581 582 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 583 { 584 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val); 585 } 586 587 static inline bool tty_port_suspended(const struct tty_port *port) 588 { 589 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 590 } 591 592 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 593 { 594 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val); 595 } 596 597 static inline bool tty_port_initialized(const struct tty_port *port) 598 { 599 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 600 } 601 602 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 603 { 604 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val); 605 } 606 607 static inline bool tty_port_kopened(const struct tty_port *port) 608 { 609 return test_bit(TTY_PORT_KOPENED, &port->iflags); 610 } 611 612 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 613 { 614 assign_bit(TTY_PORT_KOPENED, &port->iflags, val); 615 } 616 617 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 618 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 619 extern int tty_port_carrier_raised(struct tty_port *port); 620 extern void tty_port_raise_dtr_rts(struct tty_port *port); 621 extern void tty_port_lower_dtr_rts(struct tty_port *port); 622 extern void tty_port_hangup(struct tty_port *port); 623 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 624 extern void tty_port_tty_wakeup(struct tty_port *port); 625 extern int tty_port_block_til_ready(struct tty_port *port, 626 struct tty_struct *tty, struct file *filp); 627 extern int tty_port_close_start(struct tty_port *port, 628 struct tty_struct *tty, struct file *filp); 629 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 630 extern void tty_port_close(struct tty_port *port, 631 struct tty_struct *tty, struct file *filp); 632 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 633 struct tty_struct *tty); 634 extern int tty_port_open(struct tty_port *port, 635 struct tty_struct *tty, struct file *filp); 636 static inline int tty_port_users(struct tty_port *port) 637 { 638 return port->count + port->blocked_open; 639 } 640 641 extern int tty_register_ldisc(struct tty_ldisc_ops *new_ldisc); 642 extern void tty_unregister_ldisc(struct tty_ldisc_ops *ldisc); 643 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 644 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 645 const char *f, int count); 646 647 /* n_tty.c */ 648 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 649 #ifdef CONFIG_TTY 650 extern void __init n_tty_init(void); 651 #else 652 static inline void n_tty_init(void) { } 653 #endif 654 655 /* tty_audit.c */ 656 #ifdef CONFIG_AUDIT 657 extern void tty_audit_exit(void); 658 extern void tty_audit_fork(struct signal_struct *sig); 659 extern int tty_audit_push(void); 660 #else 661 static inline void tty_audit_exit(void) 662 { 663 } 664 static inline void tty_audit_fork(struct signal_struct *sig) 665 { 666 } 667 static inline int tty_audit_push(void) 668 { 669 return 0; 670 } 671 #endif 672 673 /* tty_ioctl.c */ 674 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 675 unsigned int cmd, unsigned long arg); 676 677 /* vt.c */ 678 679 extern int vt_ioctl(struct tty_struct *tty, 680 unsigned int cmd, unsigned long arg); 681 682 extern long vt_compat_ioctl(struct tty_struct *tty, 683 unsigned int cmd, unsigned long arg); 684 685 /* tty_mutex.c */ 686 /* functions for preparation of BKL removal */ 687 extern void tty_lock(struct tty_struct *tty); 688 extern int tty_lock_interruptible(struct tty_struct *tty); 689 extern void tty_unlock(struct tty_struct *tty); 690 extern void tty_lock_slave(struct tty_struct *tty); 691 extern void tty_unlock_slave(struct tty_struct *tty); 692 extern void tty_set_lock_subclass(struct tty_struct *tty); 693 694 #ifdef CONFIG_PROC_FS 695 extern void proc_tty_register_driver(struct tty_driver *); 696 extern void proc_tty_unregister_driver(struct tty_driver *); 697 #else 698 static inline void proc_tty_register_driver(struct tty_driver *d) {} 699 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 700 #endif 701 702 #endif 703