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 low_latency:1; /* optional: tune for latency */ 245 struct mutex mutex; /* Locking */ 246 struct mutex buf_mutex; /* Buffer alloc lock */ 247 unsigned char *xmit_buf; /* Optional buffer */ 248 unsigned int close_delay; /* Close port delay */ 249 unsigned int closing_wait; /* Delay for output */ 250 int drain_delay; /* Set to zero if no pure time 251 based drain is needed else 252 set to size of fifo */ 253 struct kref kref; /* Ref counter */ 254 void *client_data; 255 }; 256 257 /* tty_port::iflags bits -- use atomic bit ops */ 258 #define TTY_PORT_INITIALIZED 0 /* device is initialized */ 259 #define TTY_PORT_SUSPENDED 1 /* device is suspended */ 260 #define TTY_PORT_ACTIVE 2 /* device is open */ 261 262 /* 263 * uart drivers: use the uart_port::status field and the UPSTAT_* defines 264 * for s/w-based flow control steering and carrier detection status 265 */ 266 #define TTY_PORT_CTS_FLOW 3 /* h/w flow control enabled */ 267 #define TTY_PORT_CHECK_CD 4 /* carrier detect enabled */ 268 #define TTY_PORT_KOPENED 5 /* device exclusively opened by 269 kernel */ 270 271 /* 272 * Where all of the state associated with a tty is kept while the tty 273 * is open. Since the termios state should be kept even if the tty 274 * has been closed --- for things like the baud rate, etc --- it is 275 * not stored here, but rather a pointer to the real state is stored 276 * here. Possible the winsize structure should have the same 277 * treatment, but (1) the default 80x24 is usually right and (2) it's 278 * most often used by a windowing system, which will set the correct 279 * size each time the window is created or resized anyway. 280 * - TYT, 9/14/92 281 */ 282 283 struct tty_operations; 284 285 struct tty_struct { 286 int magic; 287 struct kref kref; 288 struct device *dev; 289 struct tty_driver *driver; 290 const struct tty_operations *ops; 291 int index; 292 293 /* Protects ldisc changes: Lock tty not pty */ 294 struct ld_semaphore ldisc_sem; 295 struct tty_ldisc *ldisc; 296 297 struct mutex atomic_write_lock; 298 struct mutex legacy_mutex; 299 struct mutex throttle_mutex; 300 struct rw_semaphore termios_rwsem; 301 struct mutex winsize_mutex; 302 spinlock_t ctrl_lock; 303 spinlock_t flow_lock; 304 /* Termios values are protected by the termios rwsem */ 305 struct ktermios termios, termios_locked; 306 char name[64]; 307 struct pid *pgrp; /* Protected by ctrl lock */ 308 /* 309 * Writes protected by both ctrl lock and legacy mutex, readers must use 310 * at least one of them. 311 */ 312 struct pid *session; 313 unsigned long flags; 314 int count; 315 struct winsize winsize; /* winsize_mutex */ 316 unsigned long stopped:1, /* flow_lock */ 317 flow_stopped:1, 318 unused:BITS_PER_LONG - 2; 319 int hw_stopped; 320 unsigned long ctrl_status:8, /* ctrl_lock */ 321 packet:1, 322 unused_ctrl:BITS_PER_LONG - 9; 323 unsigned int receive_room; /* Bytes free for queue */ 324 int flow_change; 325 326 struct tty_struct *link; 327 struct fasync_struct *fasync; 328 wait_queue_head_t write_wait; 329 wait_queue_head_t read_wait; 330 struct work_struct hangup_work; 331 void *disc_data; 332 void *driver_data; 333 spinlock_t files_lock; /* protects tty_files list */ 334 struct list_head tty_files; 335 336 #define N_TTY_BUF_SIZE 4096 337 338 int closing; 339 unsigned char *write_buf; 340 int write_cnt; 341 /* If the tty has a pending do_SAK, queue it here - akpm */ 342 struct work_struct SAK_work; 343 struct tty_port *port; 344 } __randomize_layout; 345 346 /* Each of a tty's open files has private_data pointing to tty_file_private */ 347 struct tty_file_private { 348 struct tty_struct *tty; 349 struct file *file; 350 struct list_head list; 351 }; 352 353 /* tty magic number */ 354 #define TTY_MAGIC 0x5401 355 356 /* 357 * These bits are used in the flags field of the tty structure. 358 * 359 * So that interrupts won't be able to mess up the queues, 360 * copy_to_cooked must be atomic with respect to itself, as must 361 * tty->write. Thus, you must use the inline functions set_bit() and 362 * clear_bit() to make things atomic. 363 */ 364 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 365 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 366 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 367 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 368 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 369 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 370 #define TTY_PTY_LOCK 16 /* pty private */ 371 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 372 #define TTY_HUPPED 18 /* Post driver->hangup() */ 373 #define TTY_HUPPING 19 /* Hangup in progress */ 374 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */ 375 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 376 377 /* Values for tty->flow_change */ 378 #define TTY_THROTTLE_SAFE 1 379 #define TTY_UNTHROTTLE_SAFE 2 380 381 static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 382 { 383 tty->flow_change = val; 384 } 385 386 static inline void tty_set_flow_change(struct tty_struct *tty, int val) 387 { 388 tty->flow_change = val; 389 smp_mb(); 390 } 391 392 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file) 393 { 394 return file->f_flags & O_NONBLOCK || 395 test_bit(TTY_LDISC_CHANGING, &tty->flags); 396 } 397 398 static inline bool tty_io_error(struct tty_struct *tty) 399 { 400 return test_bit(TTY_IO_ERROR, &tty->flags); 401 } 402 403 static inline bool tty_throttled(struct tty_struct *tty) 404 { 405 return test_bit(TTY_THROTTLED, &tty->flags); 406 } 407 408 #ifdef CONFIG_TTY 409 extern void tty_kref_put(struct tty_struct *tty); 410 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 411 extern void tty_vhangup_self(void); 412 extern void disassociate_ctty(int priv); 413 extern dev_t tty_devnum(struct tty_struct *tty); 414 extern void proc_clear_tty(struct task_struct *p); 415 extern struct tty_struct *get_current_tty(void); 416 /* tty_io.c */ 417 extern int __init tty_init(void); 418 extern const char *tty_name(const struct tty_struct *tty); 419 extern struct tty_struct *tty_kopen(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 #else 425 static inline void tty_kref_put(struct tty_struct *tty) 426 { } 427 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 428 { return NULL; } 429 static inline void tty_vhangup_self(void) 430 { } 431 static inline void disassociate_ctty(int priv) 432 { } 433 static inline dev_t tty_devnum(struct tty_struct *tty) 434 { return 0; } 435 static inline void proc_clear_tty(struct task_struct *p) 436 { } 437 static inline struct tty_struct *get_current_tty(void) 438 { return NULL; } 439 /* tty_io.c */ 440 static inline int __init tty_init(void) 441 { return 0; } 442 static inline const char *tty_name(const struct tty_struct *tty) 443 { return "(none)"; } 444 static inline struct tty_struct *tty_kopen(dev_t device) 445 { return ERR_PTR(-ENODEV); } 446 static inline void tty_kclose(struct tty_struct *tty) 447 { } 448 static inline int tty_dev_name_to_number(const char *name, dev_t *number) 449 { return -ENOTSUPP; } 450 #endif 451 452 extern struct ktermios tty_std_termios; 453 454 extern int vcs_init(void); 455 456 extern struct class *tty_class; 457 458 /** 459 * tty_kref_get - get a tty reference 460 * @tty: tty device 461 * 462 * Return a new reference to a tty object. The caller must hold 463 * sufficient locks/counts to ensure that their existing reference cannot 464 * go away 465 */ 466 467 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 468 { 469 if (tty) 470 kref_get(&tty->kref); 471 return tty; 472 } 473 474 extern const char *tty_driver_name(const struct tty_struct *tty); 475 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 476 extern int __tty_check_change(struct tty_struct *tty, int sig); 477 extern int tty_check_change(struct tty_struct *tty); 478 extern void __stop_tty(struct tty_struct *tty); 479 extern void stop_tty(struct tty_struct *tty); 480 extern void __start_tty(struct tty_struct *tty); 481 extern void start_tty(struct tty_struct *tty); 482 extern int tty_register_driver(struct tty_driver *driver); 483 extern int tty_unregister_driver(struct tty_driver *driver); 484 extern struct device *tty_register_device(struct tty_driver *driver, 485 unsigned index, struct device *dev); 486 extern struct device *tty_register_device_attr(struct tty_driver *driver, 487 unsigned index, struct device *device, 488 void *drvdata, 489 const struct attribute_group **attr_grp); 490 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 491 extern void tty_write_message(struct tty_struct *tty, char *msg); 492 extern int tty_send_xchar(struct tty_struct *tty, char ch); 493 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 494 extern int tty_chars_in_buffer(struct tty_struct *tty); 495 extern int tty_write_room(struct tty_struct *tty); 496 extern void tty_driver_flush_buffer(struct tty_struct *tty); 497 extern void tty_throttle(struct tty_struct *tty); 498 extern void tty_unthrottle(struct tty_struct *tty); 499 extern int tty_throttle_safe(struct tty_struct *tty); 500 extern int tty_unthrottle_safe(struct tty_struct *tty); 501 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 502 extern int is_current_pgrp_orphaned(void); 503 extern void tty_hangup(struct tty_struct *tty); 504 extern void tty_vhangup(struct tty_struct *tty); 505 extern void tty_vhangup_session(struct tty_struct *tty); 506 extern int tty_hung_up_p(struct file *filp); 507 extern void do_SAK(struct tty_struct *tty); 508 extern void __do_SAK(struct tty_struct *tty); 509 extern void tty_open_proc_set_tty(struct file *filp, struct tty_struct *tty); 510 extern int tty_signal_session_leader(struct tty_struct *tty, int exit_session); 511 extern void session_clear_tty(struct pid *session); 512 extern void no_tty(void); 513 extern void tty_buffer_free_all(struct tty_port *port); 514 extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 515 extern void tty_buffer_init(struct tty_port *port); 516 extern void tty_buffer_set_lock_subclass(struct tty_port *port); 517 extern bool tty_buffer_restart_work(struct tty_port *port); 518 extern bool tty_buffer_cancel_work(struct tty_port *port); 519 extern void tty_buffer_flush_work(struct tty_port *port); 520 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 521 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 522 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 523 speed_t ibaud, speed_t obaud); 524 extern void tty_encode_baud_rate(struct tty_struct *tty, 525 speed_t ibaud, speed_t obaud); 526 527 /** 528 * tty_get_baud_rate - get tty bit rates 529 * @tty: tty to query 530 * 531 * Returns the baud rate as an integer for this terminal. The 532 * termios lock must be held by the caller and the terminal bit 533 * flags may be updated. 534 * 535 * Locking: none 536 */ 537 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 538 { 539 return tty_termios_baud_rate(&tty->termios); 540 } 541 542 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 543 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); 544 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 545 546 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 547 extern void tty_ldisc_deref(struct tty_ldisc *); 548 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 549 extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset); 550 extern int tty_ldisc_reinit(struct tty_struct *tty, int disc); 551 extern const struct seq_operations tty_ldiscs_seq_ops; 552 553 extern void tty_wakeup(struct tty_struct *tty); 554 extern void tty_ldisc_flush(struct tty_struct *tty); 555 556 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 557 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 558 unsigned int cmd, unsigned long arg); 559 extern long tty_jobctrl_ioctl(struct tty_struct *tty, struct tty_struct *real_tty, 560 struct file *file, unsigned int cmd, unsigned long arg); 561 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 562 extern void tty_default_fops(struct file_operations *fops); 563 extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 564 extern int tty_alloc_file(struct file *file); 565 extern void tty_add_file(struct tty_struct *tty, struct file *file); 566 extern void tty_free_file(struct file *file); 567 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 568 extern void tty_release_struct(struct tty_struct *tty, int idx); 569 extern int tty_release(struct inode *inode, struct file *filp); 570 extern void tty_init_termios(struct tty_struct *tty); 571 extern void tty_save_termios(struct tty_struct *tty); 572 extern int tty_standard_install(struct tty_driver *driver, 573 struct tty_struct *tty); 574 575 extern struct mutex tty_mutex; 576 577 #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 578 579 extern void tty_port_init(struct tty_port *port); 580 extern void tty_port_link_device(struct tty_port *port, 581 struct tty_driver *driver, unsigned index); 582 extern struct device *tty_port_register_device(struct tty_port *port, 583 struct tty_driver *driver, unsigned index, 584 struct device *device); 585 extern struct device *tty_port_register_device_attr(struct tty_port *port, 586 struct tty_driver *driver, unsigned index, 587 struct device *device, void *drvdata, 588 const struct attribute_group **attr_grp); 589 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 590 struct tty_driver *driver, unsigned index, 591 struct device *device); 592 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 593 struct tty_driver *driver, unsigned index, 594 struct device *device, void *drvdata, 595 const struct attribute_group **attr_grp); 596 extern void tty_port_unregister_device(struct tty_port *port, 597 struct tty_driver *driver, unsigned index); 598 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 599 extern void tty_port_free_xmit_buf(struct tty_port *port); 600 extern void tty_port_destroy(struct tty_port *port); 601 extern void tty_port_put(struct tty_port *port); 602 603 static inline struct tty_port *tty_port_get(struct tty_port *port) 604 { 605 if (port && kref_get_unless_zero(&port->kref)) 606 return port; 607 return NULL; 608 } 609 610 /* If the cts flow control is enabled, return true. */ 611 static inline bool tty_port_cts_enabled(const struct tty_port *port) 612 { 613 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 614 } 615 616 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 617 { 618 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val); 619 } 620 621 static inline bool tty_port_active(const struct tty_port *port) 622 { 623 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 624 } 625 626 static inline void tty_port_set_active(struct tty_port *port, bool val) 627 { 628 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val); 629 } 630 631 static inline bool tty_port_check_carrier(const struct tty_port *port) 632 { 633 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 634 } 635 636 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 637 { 638 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val); 639 } 640 641 static inline bool tty_port_suspended(const struct tty_port *port) 642 { 643 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 644 } 645 646 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 647 { 648 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val); 649 } 650 651 static inline bool tty_port_initialized(const struct tty_port *port) 652 { 653 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 654 } 655 656 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 657 { 658 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val); 659 } 660 661 static inline bool tty_port_kopened(const struct tty_port *port) 662 { 663 return test_bit(TTY_PORT_KOPENED, &port->iflags); 664 } 665 666 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 667 { 668 assign_bit(TTY_PORT_KOPENED, &port->iflags, val); 669 } 670 671 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 672 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 673 extern int tty_port_carrier_raised(struct tty_port *port); 674 extern void tty_port_raise_dtr_rts(struct tty_port *port); 675 extern void tty_port_lower_dtr_rts(struct tty_port *port); 676 extern void tty_port_hangup(struct tty_port *port); 677 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 678 extern void tty_port_tty_wakeup(struct tty_port *port); 679 extern int tty_port_block_til_ready(struct tty_port *port, 680 struct tty_struct *tty, struct file *filp); 681 extern int tty_port_close_start(struct tty_port *port, 682 struct tty_struct *tty, struct file *filp); 683 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 684 extern void tty_port_close(struct tty_port *port, 685 struct tty_struct *tty, struct file *filp); 686 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 687 struct tty_struct *tty); 688 extern int tty_port_open(struct tty_port *port, 689 struct tty_struct *tty, struct file *filp); 690 static inline int tty_port_users(struct tty_port *port) 691 { 692 return port->count + port->blocked_open; 693 } 694 695 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 696 extern int tty_unregister_ldisc(int disc); 697 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 698 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 699 extern void tty_ldisc_release(struct tty_struct *tty); 700 extern int __must_check tty_ldisc_init(struct tty_struct *tty); 701 extern void tty_ldisc_deinit(struct tty_struct *tty); 702 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 703 char *f, int count); 704 extern void tty_sysctl_init(void); 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); 745 746 /* vt.c */ 747 748 extern int vt_ioctl(struct tty_struct *tty, 749 unsigned int cmd, unsigned long arg); 750 751 extern long vt_compat_ioctl(struct tty_struct *tty, 752 unsigned int cmd, unsigned long arg); 753 754 /* tty_mutex.c */ 755 /* functions for preparation of BKL removal */ 756 extern void tty_lock(struct tty_struct *tty); 757 extern int tty_lock_interruptible(struct tty_struct *tty); 758 extern void tty_unlock(struct tty_struct *tty); 759 extern void tty_lock_slave(struct tty_struct *tty); 760 extern void tty_unlock_slave(struct tty_struct *tty); 761 extern void tty_set_lock_subclass(struct tty_struct *tty); 762 763 #ifdef CONFIG_PROC_FS 764 extern void proc_tty_register_driver(struct tty_driver *); 765 extern void proc_tty_unregister_driver(struct tty_driver *); 766 #else 767 static inline void proc_tty_register_driver(struct tty_driver *d) {} 768 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 769 #endif 770 771 #define tty_msg(fn, tty, f, ...) \ 772 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) 773 774 #define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) 775 #define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__) 776 #define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) 777 #define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) 778 #define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) 779 780 #define tty_info_ratelimited(tty, f, ...) \ 781 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) 782 783 #endif 784