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 <uapi/linux/tty.h> 14 #include <linux/rwsem.h> 15 #include <linux/llist.h> 16 17 18 /* 19 * Lock subclasses for tty locks 20 * 21 * TTY_LOCK_NORMAL is for normal ttys and master ptys. 22 * TTY_LOCK_SLAVE is for slave ptys only. 23 * 24 * Lock subclasses are necessary for handling nested locking with pty pairs. 25 * tty locks which use nested locking: 26 * 27 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. 28 * The stable lock order is master pty first, then slave pty. 29 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. 30 * Subclassing this lock enables the slave pty to hold its 31 * termios_rwsem when claiming the master tty_buffer lock. 32 * tty_buffer lock - slave ptys can claim nested buffer lock when handling 33 * signal chars. The stable lock order is slave pty, then 34 * master. 35 */ 36 37 enum { 38 TTY_LOCK_NORMAL = 0, 39 TTY_LOCK_SLAVE, 40 }; 41 42 /* 43 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 44 * hardcoded at present.) 45 */ 46 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 47 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 48 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 49 50 /* 51 * This character is the same as _POSIX_VDISABLE: it cannot be used as 52 * a c_cc[] character, but indicates that a particular special character 53 * isn't in use (eg VINTR has no character etc) 54 */ 55 #define __DISABLED_CHAR '\0' 56 57 struct tty_buffer { 58 union { 59 struct tty_buffer *next; 60 struct llist_node free; 61 }; 62 int used; 63 int size; 64 int commit; 65 int read; 66 int flags; 67 /* Data points here */ 68 unsigned long data[0]; 69 }; 70 71 /* Values for .flags field of tty_buffer */ 72 #define TTYB_NORMAL 1 /* buffer has no flags buffer */ 73 74 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 75 { 76 return ((unsigned char *)b->data) + ofs; 77 } 78 79 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 80 { 81 return (char *)char_buf_ptr(b, ofs) + b->size; 82 } 83 84 struct tty_bufhead { 85 struct tty_buffer *head; /* Queue head */ 86 struct work_struct work; 87 struct mutex lock; 88 atomic_t priority; 89 struct tty_buffer sentinel; 90 struct llist_head free; /* Free queue head */ 91 atomic_t mem_used; /* In-use buffers excluding free list */ 92 int mem_limit; 93 struct tty_buffer *tail; /* Active buffer */ 94 }; 95 /* 96 * When a break, frame error, or parity error happens, these codes are 97 * stuffed into the flags buffer. 98 */ 99 #define TTY_NORMAL 0 100 #define TTY_BREAK 1 101 #define TTY_FRAME 2 102 #define TTY_PARITY 3 103 #define TTY_OVERRUN 4 104 105 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 106 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 107 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 108 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 109 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 110 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 111 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 112 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 113 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 114 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 115 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 116 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 117 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 118 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 119 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 120 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 121 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 122 123 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 124 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 125 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 126 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 127 128 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 129 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 130 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 131 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 132 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 133 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 134 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 135 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 136 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 137 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 138 #define I_IXON(tty) _I_FLAG((tty), IXON) 139 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 140 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 141 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 142 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 143 144 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 145 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 146 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 147 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 148 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 149 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 150 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 151 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 152 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 153 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 154 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 155 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 156 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 157 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 158 159 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 160 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 161 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 162 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 163 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 164 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 165 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 166 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 167 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 168 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 169 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 170 171 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 172 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 173 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 174 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 175 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 176 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 177 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 178 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 179 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 180 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 181 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 182 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 183 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 184 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 185 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 186 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 187 188 struct device; 189 struct signal_struct; 190 191 /* 192 * Port level information. Each device keeps its own port level information 193 * so provide a common structure for those ports wanting to use common support 194 * routines. 195 * 196 * The tty port has a different lifetime to the tty so must be kept apart. 197 * In addition be careful as tty -> port mappings are valid for the life 198 * of the tty object but in many cases port -> tty mappings are valid only 199 * until a hangup so don't use the wrong path. 200 */ 201 202 struct tty_port; 203 204 struct tty_port_operations { 205 /* Return 1 if the carrier is raised */ 206 int (*carrier_raised)(struct tty_port *port); 207 /* Control the DTR line */ 208 void (*dtr_rts)(struct tty_port *port, int raise); 209 /* Called when the last close completes or a hangup finishes 210 IFF the port was initialized. Do not use to free resources. Called 211 under the port mutex to serialize against activate/shutdowns */ 212 void (*shutdown)(struct tty_port *port); 213 /* Called under the port mutex from tty_port_open, serialized using 214 the port mutex */ 215 /* FIXME: long term getting the tty argument *out* of this would be 216 good for consoles */ 217 int (*activate)(struct tty_port *port, struct tty_struct *tty); 218 /* Called on the final put of a port */ 219 void (*destruct)(struct tty_port *port); 220 }; 221 222 struct tty_port_client_operations { 223 int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t); 224 void (*write_wakeup)(struct tty_port *port); 225 }; 226 227 struct tty_port { 228 struct tty_bufhead buf; /* Locked internally */ 229 struct tty_struct *tty; /* Back pointer */ 230 struct tty_struct *itty; /* internal back ptr */ 231 const struct tty_port_operations *ops; /* Port operations */ 232 const struct tty_port_client_operations *client_ops; /* Port client operations */ 233 spinlock_t lock; /* Lock protecting tty field */ 234 int blocked_open; /* Waiting to open */ 235 int count; /* Usage count */ 236 wait_queue_head_t open_wait; /* Open waiters */ 237 wait_queue_head_t delta_msr_wait; /* Modem status change */ 238 unsigned long flags; /* User TTY flags ASYNC_ */ 239 unsigned long iflags; /* Internal flags TTY_PORT_ */ 240 unsigned char console:1, /* port is a console */ 241 low_latency:1; /* optional: tune for latency */ 242 struct mutex mutex; /* Locking */ 243 struct mutex buf_mutex; /* Buffer alloc lock */ 244 unsigned char *xmit_buf; /* Optional buffer */ 245 unsigned int close_delay; /* Close port delay */ 246 unsigned int closing_wait; /* Delay for output */ 247 int drain_delay; /* Set to zero if no pure time 248 based drain is needed else 249 set to size of fifo */ 250 struct kref kref; /* Ref counter */ 251 void *client_data; 252 }; 253 254 /* tty_port::iflags bits -- use atomic bit ops */ 255 #define TTY_PORT_INITIALIZED 0 /* device is initialized */ 256 #define TTY_PORT_SUSPENDED 1 /* device is suspended */ 257 #define TTY_PORT_ACTIVE 2 /* device is open */ 258 259 /* 260 * uart drivers: use the uart_port::status field and the UPSTAT_* defines 261 * for s/w-based flow control steering and carrier detection status 262 */ 263 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */ 264 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */ 265 #define TTY_PORT_KOPENED 5 /* device exclusively opened by 266 kernel */ 267 268 /* 269 * Where all of the state associated with a tty is kept while the tty 270 * is open. Since the termios state should be kept even if the tty 271 * has been closed --- for things like the baud rate, etc --- it is 272 * not stored here, but rather a pointer to the real state is stored 273 * here. Possible the winsize structure should have the same 274 * treatment, but (1) the default 80x24 is usually right and (2) it's 275 * most often used by a windowing system, which will set the correct 276 * size each time the window is created or resized anyway. 277 * - TYT, 9/14/92 278 */ 279 280 struct tty_operations; 281 282 struct tty_struct { 283 int magic; 284 struct kref kref; 285 struct device *dev; 286 struct tty_driver *driver; 287 const struct tty_operations *ops; 288 int index; 289 290 /* Protects ldisc changes: Lock tty not pty */ 291 struct ld_semaphore ldisc_sem; 292 struct tty_ldisc *ldisc; 293 294 struct mutex atomic_write_lock; 295 struct mutex legacy_mutex; 296 struct mutex throttle_mutex; 297 struct rw_semaphore termios_rwsem; 298 struct mutex winsize_mutex; 299 spinlock_t ctrl_lock; 300 spinlock_t flow_lock; 301 /* Termios values are protected by the termios rwsem */ 302 struct ktermios termios, termios_locked; 303 struct termiox *termiox; /* May be NULL for unsupported */ 304 char name[64]; 305 struct pid *pgrp; /* Protected by ctrl lock */ 306 struct pid *session; 307 unsigned long flags; 308 int count; 309 struct winsize winsize; /* winsize_mutex */ 310 unsigned long stopped:1, /* flow_lock */ 311 flow_stopped:1, 312 unused:BITS_PER_LONG - 2; 313 int hw_stopped; 314 unsigned long ctrl_status:8, /* ctrl_lock */ 315 packet:1, 316 unused_ctrl:BITS_PER_LONG - 9; 317 unsigned int receive_room; /* Bytes free for queue */ 318 int flow_change; 319 320 struct tty_struct *link; 321 struct fasync_struct *fasync; 322 wait_queue_head_t write_wait; 323 wait_queue_head_t read_wait; 324 struct work_struct hangup_work; 325 void *disc_data; 326 void *driver_data; 327 spinlock_t files_lock; /* protects tty_files list */ 328 struct list_head tty_files; 329 330 #define N_TTY_BUF_SIZE 4096 331 332 int closing; 333 unsigned char *write_buf; 334 int write_cnt; 335 /* If the tty has a pending do_SAK, queue it here - akpm */ 336 struct work_struct SAK_work; 337 struct tty_port *port; 338 } __randomize_layout; 339 340 /* Each of a tty's open files has private_data pointing to tty_file_private */ 341 struct tty_file_private { 342 struct tty_struct *tty; 343 struct file *file; 344 struct list_head list; 345 }; 346 347 /* tty magic number */ 348 #define TTY_MAGIC 0x5401 349 350 /* 351 * These bits are used in the flags field of the tty structure. 352 * 353 * So that interrupts won't be able to mess up the queues, 354 * copy_to_cooked must be atomic with respect to itself, as must 355 * tty->write. Thus, you must use the inline functions set_bit() and 356 * clear_bit() to make things atomic. 357 */ 358 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 359 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 360 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 361 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 362 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 363 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 364 #define TTY_PTY_LOCK 16 /* pty private */ 365 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 366 #define TTY_HUPPED 18 /* Post driver->hangup() */ 367 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 368 369 /* Values for tty->flow_change */ 370 #define TTY_THROTTLE_SAFE 1 371 #define TTY_UNTHROTTLE_SAFE 2 372 373 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 374 { 375 tty->flow_change = val; 376 } 377 378 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 379 { 380 tty->flow_change = val; 381 smp_mb(); 382 } 383 384 static inline bool tty_io_error(struct tty_struct *tty) 385 { 386 return test_bit(TTY_IO_ERROR, &tty->flags); 387 } 388 389 static inline bool tty_throttled(struct tty_struct *tty) 390 { 391 return test_bit(TTY_THROTTLED, &tty->flags); 392 } 393 394 #ifdef CONFIG_TTY 395 extern void tty_kref_put(struct tty_struct *tty); 396 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 397 extern void tty_vhangup_self(void); 398 extern void disassociate_ctty(int priv); 399 extern dev_t tty_devnum(struct tty_struct *tty); 400 extern void proc_clear_tty(struct task_struct *p); 401 extern struct tty_struct *get_current_tty(void); 402 /* tty_io.c */ 403 extern int __init tty_init(void); 404 extern const char *tty_name(const struct tty_struct *tty); 405 extern struct tty_struct *tty_kopen(dev_t device); 406 extern void tty_kclose(struct tty_struct *tty); 407 extern int tty_dev_name_to_number(const char *name, dev_t *number); 408 #else 409 static inline void tty_kref_put(struct tty_struct *tty) 410 { } 411 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 412 { return NULL; } 413 static inline void tty_vhangup_self(void) 414 { } 415 static inline void disassociate_ctty(int priv) 416 { } 417 static inline dev_t tty_devnum(struct tty_struct *tty) 418 { return 0; } 419 static inline void proc_clear_tty(struct task_struct *p) 420 { } 421 static inline struct tty_struct *get_current_tty(void) 422 { return NULL; } 423 /* tty_io.c */ 424 static inline int __init tty_init(void) 425 { return 0; } 426 static inline const char *tty_name(const struct tty_struct *tty) 427 { return "(none)"; } 428 static inline struct tty_struct *tty_kopen(dev_t device) 429 { return ERR_PTR(-ENODEV); } 430 static inline void tty_kclose(struct tty_struct *tty) 431 { } 432 static inline int tty_dev_name_to_number(const char *name, dev_t *number) 433 { return -ENOTSUPP; } 434 #endif 435 436 extern struct ktermios tty_std_termios; 437 438 extern int vcs_init(void); 439 440 extern struct class *tty_class; 441 442 /** 443 * tty_kref_get - get a tty reference 444 * @tty: tty device 445 * 446 * Return a new reference to a tty object. The caller must hold 447 * sufficient locks/counts to ensure that their existing reference cannot 448 * go away 449 */ 450 451 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 452 { 453 if (tty) 454 kref_get(&tty->kref); 455 return tty; 456 } 457 458 extern const char *tty_driver_name(const struct tty_struct *tty); 459 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 460 extern int __tty_check_change(struct tty_struct *tty, int sig); 461 extern int tty_check_change(struct tty_struct *tty); 462 extern void __stop_tty(struct tty_struct *tty); 463 extern void stop_tty(struct tty_struct *tty); 464 extern void __start_tty(struct tty_struct *tty); 465 extern void start_tty(struct tty_struct *tty); 466 extern int tty_register_driver(struct tty_driver *driver); 467 extern int tty_unregister_driver(struct tty_driver *driver); 468 extern struct device *tty_register_device(struct tty_driver *driver, 469 unsigned index, struct device *dev); 470 extern struct device *tty_register_device_attr(struct tty_driver *driver, 471 unsigned index, struct device *device, 472 void *drvdata, 473 const struct attribute_group **attr_grp); 474 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 475 extern void tty_write_message(struct tty_struct *tty, char *msg); 476 extern int tty_send_xchar(struct tty_struct *tty, char ch); 477 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 478 extern int tty_chars_in_buffer(struct tty_struct *tty); 479 extern int tty_write_room(struct tty_struct *tty); 480 extern void tty_driver_flush_buffer(struct tty_struct *tty); 481 extern void tty_throttle(struct tty_struct *tty); 482 extern void tty_unthrottle(struct tty_struct *tty); 483 extern int tty_throttle_safe(struct tty_struct *tty); 484 extern int tty_unthrottle_safe(struct tty_struct *tty); 485 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 486 extern int is_current_pgrp_orphaned(void); 487 extern void tty_hangup(struct tty_struct *tty); 488 extern void tty_vhangup(struct tty_struct *tty); 489 extern void tty_vhangup_session(struct tty_struct *tty); 490 extern int tty_hung_up_p(struct file *filp); 491 extern void do_SAK(struct tty_struct *tty); 492 extern void __do_SAK(struct tty_struct *tty); 493 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty); 494 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session); 495 extern void session_clear_tty(struct pid *session); 496 extern void no_tty(void); 497 extern void tty_buffer_free_all(struct tty_port *port); 498 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 499 extern void tty_buffer_init(struct tty_port *port); 500 extern void tty_buffer_set_lock_subclass(struct tty_port *port); 501 extern bool tty_buffer_restart_work(struct tty_port *port); 502 extern bool tty_buffer_cancel_work(struct tty_port *port); 503 extern void tty_buffer_flush_work(struct tty_port *port); 504 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 505 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 506 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 507 speed_t ibaud, speed_t obaud); 508 extern void tty_encode_baud_rate(struct tty_struct *tty, 509 speed_t ibaud, speed_t obaud); 510 511 /** 512 * tty_get_baud_rate - get tty bit rates 513 * @tty: tty to query 514 * 515 * Returns the baud rate as an integer for this terminal. The 516 * termios lock must be held by the caller and the terminal bit 517 * flags may be updated. 518 * 519 * Locking: none 520 */ 521 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 522 { 523 return tty_termios_baud_rate(&tty->termios); 524 } 525 526 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 527 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 528 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 529 530 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 531 extern void tty_ldisc_deref(struct tty_ldisc *); 532 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 533 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset); 534 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc); 535 extern const struct file_operations tty_ldiscs_proc_fops; 536 537 extern void tty_wakeup(struct tty_struct *tty); 538 extern void tty_ldisc_flush(struct tty_struct *tty); 539 540 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 541 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 542 unsigned int cmd, unsigned long arg); 543 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty, 544 struct file *file, unsigned int cmd, unsigned long arg); 545 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 546 extern void tty_default_fops(struct file_operations *fops); 547 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 548 extern int tty_alloc_file(struct file *file); 549 extern void tty_add_file(struct tty_struct *tty, struct file *file); 550 extern void tty_free_file(struct file *file); 551 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 552 extern void tty_release_struct(struct tty_struct *tty, int idx); 553 extern int tty_release(struct inode *inode, struct file *filp); 554 extern void tty_init_termios(struct tty_struct *tty); 555 extern int tty_standard_install(struct tty_driver *driver, 556 struct tty_struct *tty); 557 558 extern struct mutex tty_mutex; 559 560 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 561 562 extern void tty_port_init(struct tty_port *port); 563 extern void tty_port_link_device(struct tty_port *port, 564 struct tty_driver *driver, unsigned index); 565 extern struct device *tty_port_register_device(struct tty_port *port, 566 struct tty_driver *driver, unsigned index, 567 struct device *device); 568 extern struct device *tty_port_register_device_attr(struct tty_port *port, 569 struct tty_driver *driver, unsigned index, 570 struct device *device, void *drvdata, 571 const struct attribute_group **attr_grp); 572 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 573 struct tty_driver *driver, unsigned index, 574 struct device *device); 575 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 576 struct tty_driver *driver, unsigned index, 577 struct device *device, void *drvdata, 578 const struct attribute_group **attr_grp); 579 extern void tty_port_unregister_device(struct tty_port *port, 580 struct tty_driver *driver, unsigned index); 581 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 582 extern void tty_port_free_xmit_buf(struct tty_port *port); 583 extern void tty_port_destroy(struct tty_port *port); 584 extern void tty_port_put(struct tty_port *port); 585 586 static inline struct tty_port *tty_port_get(struct tty_port *port) 587 { 588 if (port && kref_get_unless_zero(&port->kref)) 589 return port; 590 return NULL; 591 } 592 593 /* If the cts flow control is enabled, return true. */ 594 static inline bool tty_port_cts_enabled(struct tty_port *port) 595 { 596 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 597 } 598 599 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 600 { 601 if (val) 602 set_bit(TTY_PORT_CTS_FLOW, &port->iflags); 603 else 604 clear_bit(TTY_PORT_CTS_FLOW, &port->iflags); 605 } 606 607 static inline bool tty_port_active(struct tty_port *port) 608 { 609 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 610 } 611 612 static inline void tty_port_set_active(struct tty_port *port, bool val) 613 { 614 if (val) 615 set_bit(TTY_PORT_ACTIVE, &port->iflags); 616 else 617 clear_bit(TTY_PORT_ACTIVE, &port->iflags); 618 } 619 620 static inline bool tty_port_check_carrier(struct tty_port *port) 621 { 622 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 623 } 624 625 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 626 { 627 if (val) 628 set_bit(TTY_PORT_CHECK_CD, &port->iflags); 629 else 630 clear_bit(TTY_PORT_CHECK_CD, &port->iflags); 631 } 632 633 static inline bool tty_port_suspended(struct tty_port *port) 634 { 635 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 636 } 637 638 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 639 { 640 if (val) 641 set_bit(TTY_PORT_SUSPENDED, &port->iflags); 642 else 643 clear_bit(TTY_PORT_SUSPENDED, &port->iflags); 644 } 645 646 static inline bool tty_port_initialized(struct tty_port *port) 647 { 648 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 649 } 650 651 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 652 { 653 if (val) 654 set_bit(TTY_PORT_INITIALIZED, &port->iflags); 655 else 656 clear_bit(TTY_PORT_INITIALIZED, &port->iflags); 657 } 658 659 static inline bool tty_port_kopened(struct tty_port *port) 660 { 661 return test_bit(TTY_PORT_KOPENED, &port->iflags); 662 } 663 664 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 665 { 666 if (val) 667 set_bit(TTY_PORT_KOPENED, &port->iflags); 668 else 669 clear_bit(TTY_PORT_KOPENED, &port->iflags); 670 } 671 672 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 673 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 674 extern int tty_port_carrier_raised(struct tty_port *port); 675 extern void tty_port_raise_dtr_rts(struct tty_port *port); 676 extern void tty_port_lower_dtr_rts(struct tty_port *port); 677 extern void tty_port_hangup(struct tty_port *port); 678 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 679 extern void tty_port_tty_wakeup(struct tty_port *port); 680 extern int tty_port_block_til_ready(struct tty_port *port, 681 struct tty_struct *tty, struct file *filp); 682 extern int tty_port_close_start(struct tty_port *port, 683 struct tty_struct *tty, struct file *filp); 684 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 685 extern void tty_port_close(struct tty_port *port, 686 struct tty_struct *tty, struct file *filp); 687 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 688 struct tty_struct *tty); 689 extern int tty_port_open(struct tty_port *port, 690 struct tty_struct *tty, struct file *filp); 691 static inline int tty_port_users(struct tty_port *port) 692 { 693 return port->count + port->blocked_open; 694 } 695 696 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 697 extern int tty_unregister_ldisc(int disc); 698 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 699 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 700 extern void tty_ldisc_release(struct tty_struct *tty); 701 extern void tty_ldisc_init(struct tty_struct *tty); 702 extern void tty_ldisc_deinit(struct tty_struct *tty); 703 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 704 char *f, int count); 705 706 /* n_tty.c */ 707 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 708 #ifdef CONFIG_TTY 709 extern void __init n_tty_init(void); 710 #else 711 static inline void n_tty_init(void) { } 712 #endif 713 714 /* tty_audit.c */ 715 #ifdef CONFIG_AUDIT 716 extern void tty_audit_add_data(struct tty_struct *tty, const void *data, 717 size_t size); 718 extern void tty_audit_exit(void); 719 extern void tty_audit_fork(struct signal_struct *sig); 720 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 721 extern int tty_audit_push(void); 722 #else 723 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data, 724 size_t size) 725 { 726 } 727 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 728 { 729 } 730 static inline void tty_audit_exit(void) 731 { 732 } 733 static inline void tty_audit_fork(struct signal_struct *sig) 734 { 735 } 736 static inline int tty_audit_push(void) 737 { 738 return 0; 739 } 740 #endif 741 742 /* tty_ioctl.c */ 743 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 744 unsigned int cmd, unsigned long arg); 745 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 746 unsigned int cmd, unsigned long arg); 747 748 /* vt.c */ 749 750 extern int vt_ioctl(struct tty_struct *tty, 751 unsigned int cmd, unsigned long arg); 752 753 extern long vt_compat_ioctl(struct tty_struct *tty, 754 unsigned int cmd, unsigned long arg); 755 756 /* tty_mutex.c */ 757 /* functions for preparation of BKL removal */ 758 extern void tty_lock(struct tty_struct *tty); 759 extern int tty_lock_interruptible(struct tty_struct *tty); 760 extern void tty_unlock(struct tty_struct *tty); 761 extern void tty_lock_slave(struct tty_struct *tty); 762 extern void tty_unlock_slave(struct tty_struct *tty); 763 extern void tty_set_lock_subclass(struct tty_struct *tty); 764 765 #ifdef CONFIG_PROC_FS 766 extern void proc_tty_register_driver(struct tty_driver *); 767 extern void proc_tty_unregister_driver(struct tty_driver *); 768 #else 769 static inline void proc_tty_register_driver(struct tty_driver *d) {} 770 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 771 #endif 772 773 #define tty_msg(fn, tty, f, ...) \ 774 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) 775 776 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) 777 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__) 778 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) 779 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) 780 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) 781 782 #define tty_info_ratelimited(tty, f, ...) \ 783 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) 784 785 #endif 786