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 /* 247 * Where all of the state associated with a tty is kept while the tty 248 * is open. Since the termios state should be kept even if the tty 249 * has been closed --- for things like the baud rate, etc --- it is 250 * not stored here, but rather a pointer to the real state is stored 251 * here. Possible the winsize structure should have the same 252 * treatment, but (1) the default 80x24 is usually right and (2) it's 253 * most often used by a windowing system, which will set the correct 254 * size each time the window is created or resized anyway. 255 * - TYT, 9/14/92 256 */ 257 258 struct tty_operations; 259 260 struct tty_struct { 261 int magic; 262 struct kref kref; 263 struct device *dev; /* class device or NULL (e.g. ptys, serdev) */ 264 struct tty_driver *driver; 265 const struct tty_operations *ops; 266 int index; 267 268 /* Protects ldisc changes: Lock tty not pty */ 269 struct ld_semaphore ldisc_sem; 270 struct tty_ldisc *ldisc; 271 272 struct mutex atomic_write_lock; 273 struct mutex legacy_mutex; 274 struct mutex throttle_mutex; 275 struct rw_semaphore termios_rwsem; 276 struct mutex winsize_mutex; 277 spinlock_t ctrl_lock; 278 spinlock_t flow_lock; 279 /* Termios values are protected by the termios rwsem */ 280 struct ktermios termios, termios_locked; 281 char name[64]; 282 struct pid *pgrp; /* Protected by ctrl lock */ 283 /* 284 * Writes protected by both ctrl lock and legacy mutex, readers must use 285 * at least one of them. 286 */ 287 struct pid *session; 288 unsigned long flags; 289 int count; 290 struct winsize winsize; /* winsize_mutex */ 291 unsigned long stopped:1, /* flow_lock */ 292 flow_stopped:1, 293 unused:BITS_PER_LONG - 2; 294 int hw_stopped; 295 unsigned long ctrl_status:8, /* ctrl_lock */ 296 packet:1, 297 unused_ctrl:BITS_PER_LONG - 9; 298 unsigned int receive_room; /* Bytes free for queue */ 299 int flow_change; 300 301 struct tty_struct *link; 302 struct fasync_struct *fasync; 303 wait_queue_head_t write_wait; 304 wait_queue_head_t read_wait; 305 struct work_struct hangup_work; 306 void *disc_data; 307 void *driver_data; 308 spinlock_t files_lock; /* protects tty_files list */ 309 struct list_head tty_files; 310 311 #define N_TTY_BUF_SIZE 4096 312 313 int closing; 314 unsigned char *write_buf; 315 int write_cnt; 316 /* If the tty has a pending do_SAK, queue it here - akpm */ 317 struct work_struct SAK_work; 318 struct tty_port *port; 319 } __randomize_layout; 320 321 /* Each of a tty's open files has private_data pointing to tty_file_private */ 322 struct tty_file_private { 323 struct tty_struct *tty; 324 struct file *file; 325 struct list_head list; 326 }; 327 328 /* tty magic number */ 329 #define TTY_MAGIC 0x5401 330 331 /* 332 * These bits are used in the flags field of the tty structure. 333 * 334 * So that interrupts won't be able to mess up the queues, 335 * copy_to_cooked must be atomic with respect to itself, as must 336 * tty->write. Thus, you must use the inline functions set_bit() and 337 * clear_bit() to make things atomic. 338 */ 339 #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 340 #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 341 #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 342 #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 343 #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 344 #define TTY_LDISC_OPEN 11 /* Line discipline is open */ 345 #define TTY_PTY_LOCK 16 /* pty private */ 346 #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 347 #define TTY_HUPPED 18 /* Post driver->hangup() */ 348 #define TTY_HUPPING 19 /* Hangup in progress */ 349 #define TTY_LDISC_CHANGING 20 /* Change pending - non-block IO */ 350 #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 351 352 static inline bool tty_io_nonblock(struct tty_struct *tty, struct file *file) 353 { 354 return file->f_flags & O_NONBLOCK || 355 test_bit(TTY_LDISC_CHANGING, &tty->flags); 356 } 357 358 static inline bool tty_io_error(struct tty_struct *tty) 359 { 360 return test_bit(TTY_IO_ERROR, &tty->flags); 361 } 362 363 static inline bool tty_throttled(struct tty_struct *tty) 364 { 365 return test_bit(TTY_THROTTLED, &tty->flags); 366 } 367 368 #ifdef CONFIG_TTY 369 extern void tty_kref_put(struct tty_struct *tty); 370 extern struct pid *tty_get_pgrp(struct tty_struct *tty); 371 extern void tty_vhangup_self(void); 372 extern void disassociate_ctty(int priv); 373 extern dev_t tty_devnum(struct tty_struct *tty); 374 extern void proc_clear_tty(struct task_struct *p); 375 extern struct tty_struct *get_current_tty(void); 376 /* tty_io.c */ 377 extern int __init tty_init(void); 378 extern const char *tty_name(const struct tty_struct *tty); 379 extern struct tty_struct *tty_kopen_exclusive(dev_t device); 380 extern struct tty_struct *tty_kopen_shared(dev_t device); 381 extern void tty_kclose(struct tty_struct *tty); 382 extern int tty_dev_name_to_number(const char *name, dev_t *number); 383 #else 384 static inline void tty_kref_put(struct tty_struct *tty) 385 { } 386 static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 387 { return NULL; } 388 static inline void tty_vhangup_self(void) 389 { } 390 static inline void disassociate_ctty(int priv) 391 { } 392 static inline dev_t tty_devnum(struct tty_struct *tty) 393 { return 0; } 394 static inline void proc_clear_tty(struct task_struct *p) 395 { } 396 static inline struct tty_struct *get_current_tty(void) 397 { return NULL; } 398 /* tty_io.c */ 399 static inline int __init tty_init(void) 400 { return 0; } 401 static inline const char *tty_name(const struct tty_struct *tty) 402 { return "(none)"; } 403 static inline struct tty_struct *tty_kopen_exclusive(dev_t device) 404 { return ERR_PTR(-ENODEV); } 405 static inline void tty_kclose(struct tty_struct *tty) 406 { } 407 static inline int tty_dev_name_to_number(const char *name, dev_t *number) 408 { return -ENOTSUPP; } 409 #endif 410 411 extern struct ktermios tty_std_termios; 412 413 extern int vcs_init(void); 414 415 extern struct class *tty_class; 416 417 /** 418 * tty_kref_get - get a tty reference 419 * @tty: tty device 420 * 421 * Return a new reference to a tty object. The caller must hold 422 * sufficient locks/counts to ensure that their existing reference cannot 423 * go away 424 */ 425 426 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 427 { 428 if (tty) 429 kref_get(&tty->kref); 430 return tty; 431 } 432 433 extern const char *tty_driver_name(const struct tty_struct *tty); 434 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 435 extern void stop_tty(struct tty_struct *tty); 436 extern void start_tty(struct tty_struct *tty); 437 extern int tty_register_driver(struct tty_driver *driver); 438 extern void tty_unregister_driver(struct tty_driver *driver); 439 extern struct device *tty_register_device(struct tty_driver *driver, 440 unsigned index, struct device *dev); 441 extern struct device *tty_register_device_attr(struct tty_driver *driver, 442 unsigned index, struct device *device, 443 void *drvdata, 444 const struct attribute_group **attr_grp); 445 extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 446 extern void tty_write_message(struct tty_struct *tty, char *msg); 447 extern int tty_send_xchar(struct tty_struct *tty, char ch); 448 extern int tty_put_char(struct tty_struct *tty, unsigned char c); 449 extern int tty_chars_in_buffer(struct tty_struct *tty); 450 extern int tty_write_room(struct tty_struct *tty); 451 extern void tty_driver_flush_buffer(struct tty_struct *tty); 452 extern void tty_throttle(struct tty_struct *tty); 453 extern void tty_unthrottle(struct tty_struct *tty); 454 extern int tty_throttle_safe(struct tty_struct *tty); 455 extern int tty_unthrottle_safe(struct tty_struct *tty); 456 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 457 extern int tty_get_icount(struct tty_struct *tty, 458 struct serial_icounter_struct *icount); 459 extern int is_current_pgrp_orphaned(void); 460 extern void tty_hangup(struct tty_struct *tty); 461 extern void tty_vhangup(struct tty_struct *tty); 462 extern int tty_hung_up_p(struct file *filp); 463 extern void do_SAK(struct tty_struct *tty); 464 extern void __do_SAK(struct tty_struct *tty); 465 extern void no_tty(void); 466 extern speed_t tty_termios_baud_rate(struct ktermios *termios); 467 extern void tty_termios_encode_baud_rate(struct ktermios *termios, 468 speed_t ibaud, speed_t obaud); 469 extern void tty_encode_baud_rate(struct tty_struct *tty, 470 speed_t ibaud, speed_t obaud); 471 472 /** 473 * tty_get_baud_rate - get tty bit rates 474 * @tty: tty to query 475 * 476 * Returns the baud rate as an integer for this terminal. The 477 * termios lock must be held by the caller and the terminal bit 478 * flags may be updated. 479 * 480 * Locking: none 481 */ 482 static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 483 { 484 return tty_termios_baud_rate(&tty->termios); 485 } 486 487 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 488 extern int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b); 489 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 490 491 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 492 extern void tty_ldisc_deref(struct tty_ldisc *); 493 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 494 extern const struct seq_operations tty_ldiscs_seq_ops; 495 496 extern void tty_wakeup(struct tty_struct *tty); 497 extern void tty_ldisc_flush(struct tty_struct *tty); 498 499 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 500 unsigned int cmd, unsigned long arg); 501 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 502 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 503 extern void tty_release_struct(struct tty_struct *tty, int idx); 504 extern void tty_init_termios(struct tty_struct *tty); 505 extern void tty_save_termios(struct tty_struct *tty); 506 extern int tty_standard_install(struct tty_driver *driver, 507 struct tty_struct *tty); 508 509 extern struct mutex tty_mutex; 510 511 extern void tty_port_init(struct tty_port *port); 512 extern void tty_port_link_device(struct tty_port *port, 513 struct tty_driver *driver, unsigned index); 514 extern struct device *tty_port_register_device(struct tty_port *port, 515 struct tty_driver *driver, unsigned index, 516 struct device *device); 517 extern struct device *tty_port_register_device_attr(struct tty_port *port, 518 struct tty_driver *driver, unsigned index, 519 struct device *device, void *drvdata, 520 const struct attribute_group **attr_grp); 521 extern struct device *tty_port_register_device_serdev(struct tty_port *port, 522 struct tty_driver *driver, unsigned index, 523 struct device *device); 524 extern struct device *tty_port_register_device_attr_serdev(struct tty_port *port, 525 struct tty_driver *driver, unsigned index, 526 struct device *device, void *drvdata, 527 const struct attribute_group **attr_grp); 528 extern void tty_port_unregister_device(struct tty_port *port, 529 struct tty_driver *driver, unsigned index); 530 extern int tty_port_alloc_xmit_buf(struct tty_port *port); 531 extern void tty_port_free_xmit_buf(struct tty_port *port); 532 extern void tty_port_destroy(struct tty_port *port); 533 extern void tty_port_put(struct tty_port *port); 534 535 static inline struct tty_port *tty_port_get(struct tty_port *port) 536 { 537 if (port && kref_get_unless_zero(&port->kref)) 538 return port; 539 return NULL; 540 } 541 542 /* If the cts flow control is enabled, return true. */ 543 static inline bool tty_port_cts_enabled(const struct tty_port *port) 544 { 545 return test_bit(TTY_PORT_CTS_FLOW, &port->iflags); 546 } 547 548 static inline void tty_port_set_cts_flow(struct tty_port *port, bool val) 549 { 550 assign_bit(TTY_PORT_CTS_FLOW, &port->iflags, val); 551 } 552 553 static inline bool tty_port_active(const struct tty_port *port) 554 { 555 return test_bit(TTY_PORT_ACTIVE, &port->iflags); 556 } 557 558 static inline void tty_port_set_active(struct tty_port *port, bool val) 559 { 560 assign_bit(TTY_PORT_ACTIVE, &port->iflags, val); 561 } 562 563 static inline bool tty_port_check_carrier(const struct tty_port *port) 564 { 565 return test_bit(TTY_PORT_CHECK_CD, &port->iflags); 566 } 567 568 static inline void tty_port_set_check_carrier(struct tty_port *port, bool val) 569 { 570 assign_bit(TTY_PORT_CHECK_CD, &port->iflags, val); 571 } 572 573 static inline bool tty_port_suspended(const struct tty_port *port) 574 { 575 return test_bit(TTY_PORT_SUSPENDED, &port->iflags); 576 } 577 578 static inline void tty_port_set_suspended(struct tty_port *port, bool val) 579 { 580 assign_bit(TTY_PORT_SUSPENDED, &port->iflags, val); 581 } 582 583 static inline bool tty_port_initialized(const struct tty_port *port) 584 { 585 return test_bit(TTY_PORT_INITIALIZED, &port->iflags); 586 } 587 588 static inline void tty_port_set_initialized(struct tty_port *port, bool val) 589 { 590 assign_bit(TTY_PORT_INITIALIZED, &port->iflags, val); 591 } 592 593 static inline bool tty_port_kopened(const struct tty_port *port) 594 { 595 return test_bit(TTY_PORT_KOPENED, &port->iflags); 596 } 597 598 static inline void tty_port_set_kopened(struct tty_port *port, bool val) 599 { 600 assign_bit(TTY_PORT_KOPENED, &port->iflags, val); 601 } 602 603 extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 604 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 605 extern int tty_port_carrier_raised(struct tty_port *port); 606 extern void tty_port_raise_dtr_rts(struct tty_port *port); 607 extern void tty_port_lower_dtr_rts(struct tty_port *port); 608 extern void tty_port_hangup(struct tty_port *port); 609 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 610 extern void tty_port_tty_wakeup(struct tty_port *port); 611 extern int tty_port_block_til_ready(struct tty_port *port, 612 struct tty_struct *tty, struct file *filp); 613 extern int tty_port_close_start(struct tty_port *port, 614 struct tty_struct *tty, struct file *filp); 615 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 616 extern void tty_port_close(struct tty_port *port, 617 struct tty_struct *tty, struct file *filp); 618 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 619 struct tty_struct *tty); 620 extern int tty_port_open(struct tty_port *port, 621 struct tty_struct *tty, struct file *filp); 622 static inline int tty_port_users(struct tty_port *port) 623 { 624 return port->count + port->blocked_open; 625 } 626 627 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 628 extern int tty_unregister_ldisc(int disc); 629 extern int tty_set_ldisc(struct tty_struct *tty, int disc); 630 extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p, 631 char *f, int count); 632 633 /* n_tty.c */ 634 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 635 #ifdef CONFIG_TTY 636 extern void __init n_tty_init(void); 637 #else 638 static inline void n_tty_init(void) { } 639 #endif 640 641 /* tty_audit.c */ 642 #ifdef CONFIG_AUDIT 643 extern void tty_audit_exit(void); 644 extern void tty_audit_fork(struct signal_struct *sig); 645 extern int tty_audit_push(void); 646 #else 647 static inline void tty_audit_exit(void) 648 { 649 } 650 static inline void tty_audit_fork(struct signal_struct *sig) 651 { 652 } 653 static inline int tty_audit_push(void) 654 { 655 return 0; 656 } 657 #endif 658 659 /* tty_ioctl.c */ 660 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 661 unsigned int cmd, unsigned long arg); 662 663 /* vt.c */ 664 665 extern int vt_ioctl(struct tty_struct *tty, 666 unsigned int cmd, unsigned long arg); 667 668 extern long vt_compat_ioctl(struct tty_struct *tty, 669 unsigned int cmd, unsigned long arg); 670 671 /* tty_mutex.c */ 672 /* functions for preparation of BKL removal */ 673 extern void tty_lock(struct tty_struct *tty); 674 extern int tty_lock_interruptible(struct tty_struct *tty); 675 extern void tty_unlock(struct tty_struct *tty); 676 extern void tty_lock_slave(struct tty_struct *tty); 677 extern void tty_unlock_slave(struct tty_struct *tty); 678 extern void tty_set_lock_subclass(struct tty_struct *tty); 679 680 #ifdef CONFIG_PROC_FS 681 extern void proc_tty_register_driver(struct tty_driver *); 682 extern void proc_tty_unregister_driver(struct tty_driver *); 683 #else 684 static inline void proc_tty_register_driver(struct tty_driver *d) {} 685 static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 686 #endif 687 688 #endif 689