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_throttle(struct tty_struct *tty); 465 extern void tty_unthrottle(struct tty_struct *tty); 466 extern int tty_throttle_safe(struct tty_struct *tty); 467 extern int tty_unthrottle_safe(struct tty_struct *tty); 468 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 469 extern int tty_get_icount(struct tty_struct *tty, 470 struct serial_icounter_struct *icount); 471 extern int is_current_pgrp_orphaned(void); 472 extern void tty_hangup(struct tty_struct *tty); 473 extern void tty_vhangup(struct tty_struct *tty); 474 extern int tty_hung_up_p(struct file *filp); 475 extern void do_SAK(struct tty_struct *tty); 476 extern void __do_SAK(struct tty_struct *tty); 477 extern void no_tty(void); 478 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 479 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 480 speed_t ibaud, speed_t obaud); 481 extern void tty_encode_baud_rate(struct tty_struct *tty, 482 speed_t ibaud, speed_t obaud); 483 484 /** 485 * tty_get_baud_rate - get tty bit rates 486 * @tty: tty to query 487 * 488 * Returns the baud rate as an integer for this terminal. The 489 * termios lock must be held by the caller and the terminal bit 490 * flags may be updated. 491 * 492 * Locking: none 493 */ 494 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 495 { 496 return tty_termios_baud_rate(&tty->termios); 497 } 498 499 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 500 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); 501 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 502 503 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 504 extern void tty_ldisc_deref(struct tty_ldisc *); 505 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 506 extern const struct seq_operations tty_ldiscs_seq_ops; 507 508 extern void tty_wakeup(struct tty_struct *tty); 509 extern void tty_ldisc_flush(struct tty_struct *tty); 510 511 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 512 unsigned int cmd, unsigned long arg); 513 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 514 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 515 extern void tty_release_struct(struct tty_struct *tty, int idx); 516 extern void tty_init_termios(struct tty_struct *tty); 517 extern void tty_save_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; 522 523 extern void tty_port_init(struct tty_port *port); 524 extern void tty_port_link_device(struct tty_port *port, 525 struct tty_driver *driver, unsigned index); 526 extern struct device *tty_port_register_device(struct tty_port *port, 527 struct tty_driver *driver, unsigned index, 528 struct device *device); 529 extern struct device *tty_port_register_device_attr(struct tty_port *port, 530 struct tty_driver *driver, unsigned index, 531 struct device *device, void *drvdata, 532 const struct attribute_group **attr_grp); 533 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 534 struct tty_driver *driver, unsigned index, 535 struct device *device); 536 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 537 struct tty_driver *driver, unsigned index, 538 struct device *device, void *drvdata, 539 const struct attribute_group **attr_grp); 540 extern void tty_port_unregister_device(struct tty_port *port, 541 struct tty_driver *driver, unsigned index); 542 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 543 extern void tty_port_free_xmit_buf(struct tty_port *port); 544 extern void tty_port_destroy(struct tty_port *port); 545 extern void tty_port_put(struct tty_port *port); 546 547 static inline struct tty_port *tty_port_get(struct tty_port *port) 548 { 549 if (port && kref_get_unless_zero(&port->kref)) 550 return port; 551 return NULL; 552 } 553 554 /* If the cts flow control is enabled, return true. */ 555 static inline bool tty_port_cts_enabled(const struct tty_port *port) 556 { 557 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 558 } 559 560 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 561 { 562 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val); 563 } 564 565 static inline bool tty_port_active(const struct tty_port *port) 566 { 567 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 568 } 569 570 static inline void tty_port_set_active(struct tty_port *port, bool val) 571 { 572 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val); 573 } 574 575 static inline bool tty_port_check_carrier(const struct tty_port *port) 576 { 577 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 578 } 579 580 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 581 { 582 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val); 583 } 584 585 static inline bool tty_port_suspended(const struct tty_port *port) 586 { 587 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 588 } 589 590 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 591 { 592 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val); 593 } 594 595 static inline bool tty_port_initialized(const struct tty_port *port) 596 { 597 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 598 } 599 600 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 601 { 602 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val); 603 } 604 605 static inline bool tty_port_kopened(const struct tty_port *port) 606 { 607 return test_bit(TTY_PORT_KOPENED, &port->iflags); 608 } 609 610 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 611 { 612 assign_bit(TTY_PORT_KOPENED, &port->iflags, val); 613 } 614 615 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 616 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 617 extern int tty_port_carrier_raised(struct tty_port *port); 618 extern void tty_port_raise_dtr_rts(struct tty_port *port); 619 extern void tty_port_lower_dtr_rts(struct tty_port *port); 620 extern void tty_port_hangup(struct tty_port *port); 621 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 622 extern void tty_port_tty_wakeup(struct tty_port *port); 623 extern int tty_port_block_til_ready(struct tty_port *port, 624 struct tty_struct *tty, struct file *filp); 625 extern int tty_port_close_start(struct tty_port *port, 626 struct tty_struct *tty, struct file *filp); 627 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 628 extern void tty_port_close(struct tty_port *port, 629 struct tty_struct *tty, struct file *filp); 630 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 631 struct tty_struct *tty); 632 extern int tty_port_open(struct tty_port *port, 633 struct tty_struct *tty, struct file *filp); 634 static inline int tty_port_users(struct tty_port *port) 635 { 636 return port->count + port->blocked_open; 637 } 638 639 extern int tty_register_ldisc(struct tty_ldisc_ops *new_ldisc); 640 extern void tty_unregister_ldisc(struct tty_ldisc_ops *ldisc); 641 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 642 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 643 const char *f, int count); 644 645 /* n_tty.c */ 646 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 647 #ifdef CONFIG_TTY 648 extern void __init n_tty_init(void); 649 #else 650 static inline void n_tty_init(void) { } 651 #endif 652 653 /* tty_audit.c */ 654 #ifdef CONFIG_AUDIT 655 extern void tty_audit_exit(void); 656 extern void tty_audit_fork(struct signal_struct *sig); 657 extern int tty_audit_push(void); 658 #else 659 static inline void tty_audit_exit(void) 660 { 661 } 662 static inline void tty_audit_fork(struct signal_struct *sig) 663 { 664 } 665 static inline int tty_audit_push(void) 666 { 667 return 0; 668 } 669 #endif 670 671 /* tty_ioctl.c */ 672 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 673 unsigned int cmd, unsigned long arg); 674 675 /* vt.c */ 676 677 extern int vt_ioctl(struct tty_struct *tty, 678 unsigned int cmd, unsigned long arg); 679 680 extern long vt_compat_ioctl(struct tty_struct *tty, 681 unsigned int cmd, unsigned long arg); 682 683 /* tty_mutex.c */ 684 /* functions for preparation of BKL removal */ 685 extern void tty_lock(struct tty_struct *tty); 686 extern int tty_lock_interruptible(struct tty_struct *tty); 687 extern void tty_unlock(struct tty_struct *tty); 688 extern void tty_lock_slave(struct tty_struct *tty); 689 extern void tty_unlock_slave(struct tty_struct *tty); 690 extern void tty_set_lock_subclass(struct tty_struct *tty); 691 692 #ifdef CONFIG_PROC_FS 693 extern void proc_tty_register_driver(struct tty_driver *); 694 extern void proc_tty_unregister_driver(struct tty_driver *); 695 #else 696 static inline void proc_tty_register_driver(struct tty_driver *d) {} 697 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 698 #endif 699 700 #endif 701