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 * Lock subclasses for tty locks 21 * 22 * TTY_LOCK_NORMAL is for normal ttys and master ptys. 23 * TTY_LOCK_SLAVE is for slave ptys only. 24 * 25 * Lock subclasses are necessary for handling nested locking with pty pairs. 26 * tty locks which use nested locking: 27 * 28 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. 29 * The stable lock order is master pty first, then slave pty. 30 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. 31 * Subclassing this lock enables the slave pty to hold its 32 * termios_rwsem when claiming the master tty_buffer lock. 33 * tty_buffer lock - slave ptys can claim nested buffer lock when handling 34 * signal chars. The stable lock order is slave pty, then 35 * master. 36 */ 37 38 enum { 39 TTY_LOCK_NORMAL = 0, 40 TTY_LOCK_SLAVE, 41 }; 42 43 /* 44 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 45 * hardcoded at present.) 46 */ 47 #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 48 #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 49 #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 50 51 /* 52 * This character is the same as _POSIX_VDISABLE: it cannot be used as 53 * a c_cc[] character, but indicates that a particular special character 54 * isn't in use (eg VINTR has no character etc) 55 */ 56 #define __DISABLED_CHAR '\0' 57 58 struct tty_buffer { 59 union { 60 struct tty_buffer *next; 61 struct llist_node free; 62 }; 63 int used; 64 int size; 65 int commit; 66 int read; 67 int flags; 68 /* Data points here */ 69 unsigned long data[]; 70 }; 71 72 /* Values for .flags field of tty_buffer */ 73 #define TTYB_NORMAL 1 /* buffer has no flags buffer */ 74 75 static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 76 { 77 return ((unsigned char *)b->data) + ofs; 78 } 79 80 static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 81 { 82 return (char *)char_buf_ptr(b, ofs) + b->size; 83 } 84 85 struct tty_bufhead { 86 struct tty_buffer *head; /* Queue head */ 87 struct work_struct work; 88 struct mutex lock; 89 atomic_t priority; 90 struct tty_buffer sentinel; 91 struct llist_head free; /* Free queue head */ 92 atomic_t mem_used; /* In-use buffers excluding free list */ 93 int mem_limit; 94 struct tty_buffer *tail; /* Active buffer */ 95 }; 96 /* 97 * When a break, frame error, or parity error happens, these codes are 98 * stuffed into the flags buffer. 99 */ 100 #define TTY_NORMAL 0 101 #define TTY_BREAK 1 102 #define TTY_FRAME 2 103 #define TTY_PARITY 3 104 #define TTY_OVERRUN 4 105 106 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 107 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 108 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 109 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 110 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 111 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 112 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 113 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 114 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 115 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 116 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 117 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 118 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 119 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 120 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 121 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 122 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 123 124 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 125 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 126 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 127 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 128 129 #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 130 #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 131 #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 132 #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 133 #define I_INPCK(tty) _I_FLAG((tty), INPCK) 134 #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 135 #define I_INLCR(tty) _I_FLAG((tty), INLCR) 136 #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 137 #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 138 #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 139 #define I_IXON(tty) _I_FLAG((tty), IXON) 140 #define I_IXANY(tty) _I_FLAG((tty), IXANY) 141 #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 142 #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 143 #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 144 145 #define O_OPOST(tty) _O_FLAG((tty), OPOST) 146 #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 147 #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 148 #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 149 #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 150 #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 151 #define O_OFILL(tty) _O_FLAG((tty), OFILL) 152 #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 153 #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 154 #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 155 #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 156 #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 157 #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 158 #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 159 160 #define C_BAUD(tty) _C_FLAG((tty), CBAUD) 161 #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 162 #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 163 #define C_CREAD(tty) _C_FLAG((tty), CREAD) 164 #define C_PARENB(tty) _C_FLAG((tty), PARENB) 165 #define C_PARODD(tty) _C_FLAG((tty), PARODD) 166 #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 167 #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 168 #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 169 #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 170 #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 171 172 #define L_ISIG(tty) _L_FLAG((tty), ISIG) 173 #define L_ICANON(tty) _L_FLAG((tty), ICANON) 174 #define L_XCASE(tty) _L_FLAG((tty), XCASE) 175 #define L_ECHO(tty) _L_FLAG((tty), ECHO) 176 #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 177 #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 178 #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 179 #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 180 #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 181 #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 182 #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 183 #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 184 #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 185 #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 186 #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 187 #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 188 189 struct device; 190 struct signal_struct; 191 192 /* 193 * Port level information. Each device keeps its own port level information 194 * so provide a common structure for those ports wanting to use common support 195 * routines. 196 * 197 * The tty port has a different lifetime to the tty so must be kept apart. 198 * In addition be careful as tty -> port mappings are valid for the life 199 * of the tty object but in many cases port -> tty mappings are valid only 200 * until a hangup so don't use the wrong path. 201 */ 202 203 struct tty_port; 204 205 struct tty_port_operations { 206 /* Return 1 if the carrier is raised */ 207 int (*carrier_raised)(struct tty_port *port); 208 /* Control the DTR line */ 209 void (*dtr_rts)(struct tty_port *port, int raise); 210 /* Called when the last close completes or a hangup finishes 211 IFF the port was initialized. Do not use to free resources. Called 212 under the port mutex to serialize against activate/shutdowns */ 213 void (*shutdown)(struct tty_port *port); 214 /* Called under the port mutex from tty_port_open, serialized using 215 the port mutex */ 216 /* FIXME: long term getting the tty argument *out* of this would be 217 good for consoles */ 218 int (*activate)(struct tty_port *port, struct tty_struct *tty); 219 /* Called on the final put of a port */ 220 void (*destruct)(struct tty_port *port); 221 }; 222 223 struct tty_port_client_operations { 224 int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t); 225 void (*write_wakeup)(struct tty_port *port); 226 }; 227 228 extern const struct tty_port_client_operations tty_port_default_client_ops; 229 230 struct tty_port { 231 struct tty_bufhead buf; /* Locked internally */ 232 struct tty_struct *tty; /* Back pointer */ 233 struct tty_struct *itty; /* internal back ptr */ 234 const struct tty_port_operations *ops; /* Port operations */ 235 const struct tty_port_client_operations *client_ops; /* Port client operations */ 236 spinlock_t lock; /* Lock protecting tty field */ 237 int blocked_open; /* Waiting to open */ 238 int count; /* Usage count */ 239 wait_queue_head_t open_wait; /* Open waiters */ 240 wait_queue_head_t delta_msr_wait; /* Modem status change */ 241 unsigned long flags; /* User TTY flags ASYNC_ */ 242 unsigned long iflags; /* Internal flags TTY_PORT_ */ 243 unsigned char console:1; /* port is a console */ 244 struct mutex mutex; /* Locking */ 245 struct mutex buf_mutex; /* Buffer alloc lock */ 246 unsigned char *xmit_buf; /* Optional buffer */ 247 unsigned int close_delay; /* Close port delay */ 248 unsigned int closing_wait; /* Delay for output */ 249 int drain_delay; /* Set to zero if no pure time 250 based drain is needed else 251 set to size of fifo */ 252 struct kref kref; /* Ref counter */ 253 void *client_data; 254 }; 255 256 /* tty_port::iflags bits -- use atomic bit ops */ 257 #define TTY_PORT_INITIALIZED 0 /* device is initialized */ 258 #define TTY_PORT_SUSPENDED 1 /* device is suspended */ 259 #define TTY_PORT_ACTIVE 2 /* device is open */ 260 261 /* 262 * uart drivers: use the uart_port::status field and the UPSTAT_* defines 263 * for s/w-based flow control steering and carrier detection status 264 */ 265 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */ 266 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */ 267 #define TTY_PORT_KOPENED 5 /* device exclusively opened by 268 kernel */ 269 270 /* 271 * Where all of the state associated with a tty is kept while the tty 272 * is open. Since the termios state should be kept even if the tty 273 * has been closed --- for things like the baud rate, etc --- it is 274 * not stored here, but rather a pointer to the real state is stored 275 * here. Possible the winsize structure should have the same 276 * treatment, but (1) the default 80x24 is usually right and (2) it's 277 * most often used by a windowing system, which will set the correct 278 * size each time the window is created or resized anyway. 279 * - TYT, 9/14/92 280 */ 281 282 struct tty_operations; 283 284 struct tty_struct { 285 int magic; 286 struct kref kref; 287 struct device *dev; 288 struct tty_driver *driver; 289 const struct tty_operations *ops; 290 int index; 291 292 /* Protects ldisc changes: Lock tty not pty */ 293 struct ld_semaphore ldisc_sem; 294 struct tty_ldisc *ldisc; 295 296 struct mutex atomic_write_lock; 297 struct mutex legacy_mutex; 298 struct mutex throttle_mutex; 299 struct rw_semaphore termios_rwsem; 300 struct mutex winsize_mutex; 301 spinlock_t ctrl_lock; 302 spinlock_t flow_lock; 303 /* Termios values are protected by the termios rwsem */ 304 struct ktermios termios, termios_locked; 305 char name[64]; 306 struct pid *pgrp; /* Protected by ctrl lock */ 307 /* 308 * Writes protected by both ctrl lock and legacy mutex, readers must use 309 * at least one of them. 310 */ 311 struct pid *session; 312 unsigned long flags; 313 int count; 314 struct winsize winsize; /* winsize_mutex */ 315 unsigned long stopped:1, /* flow_lock */ 316 flow_stopped:1, 317 unused:BITS_PER_LONG - 2; 318 int hw_stopped; 319 unsigned long ctrl_status:8, /* ctrl_lock */ 320 packet:1, 321 unused_ctrl:BITS_PER_LONG - 9; 322 unsigned int receive_room; /* Bytes free for queue */ 323 int flow_change; 324 325 struct tty_struct *link; 326 struct fasync_struct *fasync; 327 wait_queue_head_t write_wait; 328 wait_queue_head_t read_wait; 329 struct work_struct hangup_work; 330 void *disc_data; 331 void *driver_data; 332 spinlock_t files_lock; /* protects tty_files list */ 333 struct list_head tty_files; 334 335 #define N_TTY_BUF_SIZE 4096 336 337 int closing; 338 unsigned char *write_buf; 339 int write_cnt; 340 /* If the tty has a pending do_SAK, queue it here - akpm */ 341 struct work_struct SAK_work; 342 struct tty_port *port; 343 } __randomize_layout; 344 345 /* Each of a tty's open files has private_data pointing to tty_file_private */ 346 struct tty_file_private { 347 struct tty_struct *tty; 348 struct file *file; 349 struct list_head list; 350 }; 351 352 /* tty magic number */ 353 #define TTY_MAGIC 0x5401 354 355 /* 356 * These bits are used in the flags field of the tty structure. 357 * 358 * So that interrupts won't be able to mess up the queues, 359 * copy_to_cooked must be atomic with respect to itself, as must 360 * tty->write. Thus, you must use the inline functions set_bit() and 361 * clear_bit() to make things atomic. 362 */ 363 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 364 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 365 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 366 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 367 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 368 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 369 #define TTY_PTY_LOCK 16 /* pty private */ 370 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 371 #define TTY_HUPPED 18 /* Post driver->hangup() */ 372 #define TTY_HUPPING 19 /* Hangup in progress */ 373 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */ 374 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 375 376 /* Values for tty->flow_change */ 377 #define TTY_THROTTLE_SAFE 1 378 #define TTY_UNTHROTTLE_SAFE 2 379 380 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 381 { 382 tty->flow_change = val; 383 } 384 385 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 386 { 387 tty->flow_change = val; 388 smp_mb(); 389 } 390 391 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file) 392 { 393 return file->f_flags & O_NONBLOCK || 394 test_bit(TTY_LDISC_CHANGING, &tty->flags); 395 } 396 397 static inline bool tty_io_error(struct tty_struct *tty) 398 { 399 return test_bit(TTY_IO_ERROR, &tty->flags); 400 } 401 402 static inline bool tty_throttled(struct tty_struct *tty) 403 { 404 return test_bit(TTY_THROTTLED, &tty->flags); 405 } 406 407 #ifdef CONFIG_TTY 408 extern void tty_kref_put(struct tty_struct *tty); 409 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 410 extern void tty_vhangup_self(void); 411 extern void disassociate_ctty(int priv); 412 extern dev_t tty_devnum(struct tty_struct *tty); 413 extern void proc_clear_tty(struct task_struct *p); 414 extern struct tty_struct *get_current_tty(void); 415 /* tty_io.c */ 416 extern int __init tty_init(void); 417 extern const char *tty_name(const struct tty_struct *tty); 418 extern struct tty_struct *tty_kopen_exclusive(dev_t device); 419 extern struct tty_struct *tty_kopen_shared(dev_t device); 420 extern void tty_kclose(struct tty_struct *tty); 421 extern int tty_dev_name_to_number(const char *name, dev_t *number); 422 extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout); 423 extern void tty_ldisc_unlock(struct tty_struct *tty); 424 extern ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *); 425 extern struct file *tty_release_redirect(struct tty_struct *tty); 426 #else 427 static inline void tty_kref_put(struct tty_struct *tty) 428 { } 429 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 430 { return NULL; } 431 static inline void tty_vhangup_self(void) 432 { } 433 static inline void disassociate_ctty(int priv) 434 { } 435 static inline dev_t tty_devnum(struct tty_struct *tty) 436 { return 0; } 437 static inline void proc_clear_tty(struct task_struct *p) 438 { } 439 static inline struct tty_struct *get_current_tty(void) 440 { return NULL; } 441 /* tty_io.c */ 442 static inline int __init tty_init(void) 443 { return 0; } 444 static inline const char *tty_name(const struct tty_struct *tty) 445 { return "(none)"; } 446 static inline struct tty_struct *tty_kopen_exclusive(dev_t device) 447 { return ERR_PTR(-ENODEV); } 448 static inline void tty_kclose(struct tty_struct *tty) 449 { } 450 static inline int tty_dev_name_to_number(const char *name, dev_t *number) 451 { return -ENOTSUPP; } 452 #endif 453 454 extern struct ktermios tty_std_termios; 455 456 extern int vcs_init(void); 457 458 extern struct class *tty_class; 459 460 /** 461 * tty_kref_get - get a tty reference 462 * @tty: tty device 463 * 464 * Return a new reference to a tty object. The caller must hold 465 * sufficient locks/counts to ensure that their existing reference cannot 466 * go away 467 */ 468 469 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 470 { 471 if (tty) 472 kref_get(&tty->kref); 473 return tty; 474 } 475 476 extern const char *tty_driver_name(const struct tty_struct *tty); 477 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 478 extern int __tty_check_change(struct tty_struct *tty, int sig); 479 extern int tty_check_change(struct tty_struct *tty); 480 extern void __stop_tty(struct tty_struct *tty); 481 extern void stop_tty(struct tty_struct *tty); 482 extern void __start_tty(struct tty_struct *tty); 483 extern void start_tty(struct tty_struct *tty); 484 extern int tty_register_driver(struct tty_driver *driver); 485 extern int tty_unregister_driver(struct tty_driver *driver); 486 extern struct device *tty_register_device(struct tty_driver *driver, 487 unsigned index, struct device *dev); 488 extern struct device *tty_register_device_attr(struct tty_driver *driver, 489 unsigned index, struct device *device, 490 void *drvdata, 491 const struct attribute_group **attr_grp); 492 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 493 extern void tty_write_message(struct tty_struct *tty, char *msg); 494 extern int tty_send_xchar(struct tty_struct *tty, char ch); 495 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 496 extern int tty_chars_in_buffer(struct tty_struct *tty); 497 extern int tty_write_room(struct tty_struct *tty); 498 extern void tty_driver_flush_buffer(struct tty_struct *tty); 499 extern void tty_throttle(struct tty_struct *tty); 500 extern void tty_unthrottle(struct tty_struct *tty); 501 extern int tty_throttle_safe(struct tty_struct *tty); 502 extern int tty_unthrottle_safe(struct tty_struct *tty); 503 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 504 extern int tty_get_icount(struct tty_struct *tty, 505 struct serial_icounter_struct *icount); 506 extern int is_current_pgrp_orphaned(void); 507 extern void tty_hangup(struct tty_struct *tty); 508 extern void tty_vhangup(struct tty_struct *tty); 509 extern void tty_vhangup_session(struct tty_struct *tty); 510 extern int tty_hung_up_p(struct file *filp); 511 extern void do_SAK(struct tty_struct *tty); 512 extern void __do_SAK(struct tty_struct *tty); 513 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty); 514 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session); 515 extern void session_clear_tty(struct pid *session); 516 extern void no_tty(void); 517 extern void tty_buffer_free_all(struct tty_port *port); 518 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 519 extern void tty_buffer_init(struct tty_port *port); 520 extern void tty_buffer_set_lock_subclass(struct tty_port *port); 521 extern bool tty_buffer_restart_work(struct tty_port *port); 522 extern bool tty_buffer_cancel_work(struct tty_port *port); 523 extern void tty_buffer_flush_work(struct tty_port *port); 524 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 525 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 526 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 527 speed_t ibaud, speed_t obaud); 528 extern void tty_encode_baud_rate(struct tty_struct *tty, 529 speed_t ibaud, speed_t obaud); 530 531 /** 532 * tty_get_baud_rate - get tty bit rates 533 * @tty: tty to query 534 * 535 * Returns the baud rate as an integer for this terminal. The 536 * termios lock must be held by the caller and the terminal bit 537 * flags may be updated. 538 * 539 * Locking: none 540 */ 541 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 542 { 543 return tty_termios_baud_rate(&tty->termios); 544 } 545 546 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 547 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); 548 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 549 550 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 551 extern void tty_ldisc_deref(struct tty_ldisc *); 552 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 553 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset); 554 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc); 555 extern const struct seq_operations tty_ldiscs_seq_ops; 556 557 extern void tty_wakeup(struct tty_struct *tty); 558 extern void tty_ldisc_flush(struct tty_struct *tty); 559 560 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 561 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 562 unsigned int cmd, unsigned long arg); 563 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty, 564 struct file *file, unsigned int cmd, unsigned long arg); 565 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 566 extern void tty_default_fops(struct file_operations *fops); 567 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 568 extern int tty_alloc_file(struct file *file); 569 extern void tty_add_file(struct tty_struct *tty, struct file *file); 570 extern void tty_free_file(struct file *file); 571 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 572 extern void tty_release_struct(struct tty_struct *tty, int idx); 573 extern int tty_release(struct inode *inode, struct file *filp); 574 extern void tty_init_termios(struct tty_struct *tty); 575 extern void tty_save_termios(struct tty_struct *tty); 576 extern int tty_standard_install(struct tty_driver *driver, 577 struct tty_struct *tty); 578 579 extern struct mutex tty_mutex; 580 581 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 582 583 extern void tty_port_init(struct tty_port *port); 584 extern void tty_port_link_device(struct tty_port *port, 585 struct tty_driver *driver, unsigned index); 586 extern struct device *tty_port_register_device(struct tty_port *port, 587 struct tty_driver *driver, unsigned index, 588 struct device *device); 589 extern struct device *tty_port_register_device_attr(struct tty_port *port, 590 struct tty_driver *driver, unsigned index, 591 struct device *device, void *drvdata, 592 const struct attribute_group **attr_grp); 593 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 594 struct tty_driver *driver, unsigned index, 595 struct device *device); 596 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 597 struct tty_driver *driver, unsigned index, 598 struct device *device, void *drvdata, 599 const struct attribute_group **attr_grp); 600 extern void tty_port_unregister_device(struct tty_port *port, 601 struct tty_driver *driver, unsigned index); 602 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 603 extern void tty_port_free_xmit_buf(struct tty_port *port); 604 extern void tty_port_destroy(struct tty_port *port); 605 extern void tty_port_put(struct tty_port *port); 606 607 static inline struct tty_port *tty_port_get(struct tty_port *port) 608 { 609 if (port && kref_get_unless_zero(&port->kref)) 610 return port; 611 return NULL; 612 } 613 614 /* If the cts flow control is enabled, return true. */ 615 static inline bool tty_port_cts_enabled(const struct tty_port *port) 616 { 617 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 618 } 619 620 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 621 { 622 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val); 623 } 624 625 static inline bool tty_port_active(const struct tty_port *port) 626 { 627 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 628 } 629 630 static inline void tty_port_set_active(struct tty_port *port, bool val) 631 { 632 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val); 633 } 634 635 static inline bool tty_port_check_carrier(const struct tty_port *port) 636 { 637 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 638 } 639 640 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 641 { 642 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val); 643 } 644 645 static inline bool tty_port_suspended(const struct tty_port *port) 646 { 647 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 648 } 649 650 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 651 { 652 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val); 653 } 654 655 static inline bool tty_port_initialized(const struct tty_port *port) 656 { 657 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 658 } 659 660 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 661 { 662 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val); 663 } 664 665 static inline bool tty_port_kopened(const struct tty_port *port) 666 { 667 return test_bit(TTY_PORT_KOPENED, &port->iflags); 668 } 669 670 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 671 { 672 assign_bit(TTY_PORT_KOPENED, &port->iflags, val); 673 } 674 675 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 676 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 677 extern int tty_port_carrier_raised(struct tty_port *port); 678 extern void tty_port_raise_dtr_rts(struct tty_port *port); 679 extern void tty_port_lower_dtr_rts(struct tty_port *port); 680 extern void tty_port_hangup(struct tty_port *port); 681 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 682 extern void tty_port_tty_wakeup(struct tty_port *port); 683 extern int tty_port_block_til_ready(struct tty_port *port, 684 struct tty_struct *tty, struct file *filp); 685 extern int tty_port_close_start(struct tty_port *port, 686 struct tty_struct *tty, struct file *filp); 687 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 688 extern void tty_port_close(struct tty_port *port, 689 struct tty_struct *tty, struct file *filp); 690 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 691 struct tty_struct *tty); 692 extern int tty_port_open(struct tty_port *port, 693 struct tty_struct *tty, struct file *filp); 694 static inline int tty_port_users(struct tty_port *port) 695 { 696 return port->count + port->blocked_open; 697 } 698 699 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 700 extern int tty_unregister_ldisc(int disc); 701 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 702 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 703 extern void tty_ldisc_release(struct tty_struct *tty); 704 extern int __must_check tty_ldisc_init(struct tty_struct *tty); 705 extern void tty_ldisc_deinit(struct tty_struct *tty); 706 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 707 char *f, int count); 708 extern void tty_sysctl_init(void); 709 710 /* n_tty.c */ 711 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 712 #ifdef CONFIG_TTY 713 extern void __init n_tty_init(void); 714 #else 715 static inline void n_tty_init(void) { } 716 #endif 717 718 /* tty_audit.c */ 719 #ifdef CONFIG_AUDIT 720 extern void tty_audit_add_data(struct tty_struct *tty, const void *data, 721 size_t size); 722 extern void tty_audit_exit(void); 723 extern void tty_audit_fork(struct signal_struct *sig); 724 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 725 extern int tty_audit_push(void); 726 #else 727 static inline void tty_audit_add_data(struct tty_struct *tty, const void *data, 728 size_t size) 729 { 730 } 731 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 732 { 733 } 734 static inline void tty_audit_exit(void) 735 { 736 } 737 static inline void tty_audit_fork(struct signal_struct *sig) 738 { 739 } 740 static inline int tty_audit_push(void) 741 { 742 return 0; 743 } 744 #endif 745 746 /* tty_ioctl.c */ 747 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 748 unsigned int cmd, unsigned long arg); 749 750 /* vt.c */ 751 752 extern int vt_ioctl(struct tty_struct *tty, 753 unsigned int cmd, unsigned long arg); 754 755 extern long vt_compat_ioctl(struct tty_struct *tty, 756 unsigned int cmd, unsigned long arg); 757 758 /* tty_mutex.c */ 759 /* functions for preparation of BKL removal */ 760 extern void tty_lock(struct tty_struct *tty); 761 extern int tty_lock_interruptible(struct tty_struct *tty); 762 extern void tty_unlock(struct tty_struct *tty); 763 extern void tty_lock_slave(struct tty_struct *tty); 764 extern void tty_unlock_slave(struct tty_struct *tty); 765 extern void tty_set_lock_subclass(struct tty_struct *tty); 766 767 #ifdef CONFIG_PROC_FS 768 extern void proc_tty_register_driver(struct tty_driver *); 769 extern void proc_tty_unregister_driver(struct tty_driver *); 770 #else 771 static inline void proc_tty_register_driver(struct tty_driver *d) {} 772 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 773 #endif 774 775 #define tty_msg(fn, tty, f, ...) \ 776 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) 777 778 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) 779 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__) 780 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) 781 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) 782 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) 783 784 #define tty_info_ratelimited(tty, f, ...) \ 785 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) 786 787 #endif 788