at v4.6-rc2 24 kB view raw
1#ifndef _LINUX_TTY_H 2#define _LINUX_TTY_H 3 4#include <linux/fs.h> 5#include <linux/major.h> 6#include <linux/termios.h> 7#include <linux/workqueue.h> 8#include <linux/tty_driver.h> 9#include <linux/tty_ldisc.h> 10#include <linux/mutex.h> 11#include <linux/tty_flags.h> 12#include <uapi/linux/tty.h> 13#include <linux/rwsem.h> 14#include <linux/llist.h> 15 16 17/* 18 * Lock subclasses for tty locks 19 * 20 * TTY_LOCK_NORMAL is for normal ttys and master ptys. 21 * TTY_LOCK_SLAVE is for slave ptys only. 22 * 23 * Lock subclasses are necessary for handling nested locking with pty pairs. 24 * tty locks which use nested locking: 25 * 26 * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. 27 * The stable lock order is master pty first, then slave pty. 28 * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. 29 * Subclassing this lock enables the slave pty to hold its 30 * termios_rwsem when claiming the master tty_buffer lock. 31 * tty_buffer lock - slave ptys can claim nested buffer lock when handling 32 * signal chars. The stable lock order is slave pty, then 33 * master. 34 */ 35 36enum { 37 TTY_LOCK_NORMAL = 0, 38 TTY_LOCK_SLAVE, 39}; 40 41/* 42 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 43 * hardcoded at present.) 44 */ 45#define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 46#define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 47#define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 48 49/* 50 * This character is the same as _POSIX_VDISABLE: it cannot be used as 51 * a c_cc[] character, but indicates that a particular special character 52 * isn't in use (eg VINTR has no character etc) 53 */ 54#define __DISABLED_CHAR '\0' 55 56struct tty_buffer { 57 union { 58 struct tty_buffer *next; 59 struct llist_node free; 60 }; 61 int used; 62 int size; 63 int commit; 64 int read; 65 int flags; 66 /* Data points here */ 67 unsigned long data[0]; 68}; 69 70/* Values for .flags field of tty_buffer */ 71#define TTYB_NORMAL 1 /* buffer has no flags buffer */ 72 73static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 74{ 75 return ((unsigned char *)b->data) + ofs; 76} 77 78static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 79{ 80 return (char *)char_buf_ptr(b, ofs) + b->size; 81} 82 83struct tty_bufhead { 84 struct tty_buffer *head; /* Queue head */ 85 struct work_struct work; 86 struct mutex lock; 87 atomic_t priority; 88 struct tty_buffer sentinel; 89 struct llist_head free; /* Free queue head */ 90 atomic_t mem_used; /* In-use buffers excluding free list */ 91 int mem_limit; 92 struct tty_buffer *tail; /* Active buffer */ 93}; 94/* 95 * When a break, frame error, or parity error happens, these codes are 96 * stuffed into the flags buffer. 97 */ 98#define TTY_NORMAL 0 99#define TTY_BREAK 1 100#define TTY_FRAME 2 101#define TTY_PARITY 3 102#define TTY_OVERRUN 4 103 104#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 105#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 106#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 107#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 108#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 109#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 110#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 111#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 112#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 113#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 114#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 115#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 116#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 117#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 118#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 119#define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 120#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 121 122#define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 123#define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 124#define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 125#define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 126 127#define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 128#define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 129#define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 130#define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 131#define I_INPCK(tty) _I_FLAG((tty), INPCK) 132#define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 133#define I_INLCR(tty) _I_FLAG((tty), INLCR) 134#define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 135#define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 136#define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 137#define I_IXON(tty) _I_FLAG((tty), IXON) 138#define I_IXANY(tty) _I_FLAG((tty), IXANY) 139#define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 140#define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 141#define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 142 143#define O_OPOST(tty) _O_FLAG((tty), OPOST) 144#define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 145#define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 146#define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 147#define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 148#define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 149#define O_OFILL(tty) _O_FLAG((tty), OFILL) 150#define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 151#define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 152#define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 153#define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 154#define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 155#define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 156#define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 157 158#define C_BAUD(tty) _C_FLAG((tty), CBAUD) 159#define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 160#define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 161#define C_CREAD(tty) _C_FLAG((tty), CREAD) 162#define C_PARENB(tty) _C_FLAG((tty), PARENB) 163#define C_PARODD(tty) _C_FLAG((tty), PARODD) 164#define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 165#define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 166#define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 167#define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 168#define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) 169 170#define L_ISIG(tty) _L_FLAG((tty), ISIG) 171#define L_ICANON(tty) _L_FLAG((tty), ICANON) 172#define L_XCASE(tty) _L_FLAG((tty), XCASE) 173#define L_ECHO(tty) _L_FLAG((tty), ECHO) 174#define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 175#define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 176#define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 177#define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 178#define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 179#define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 180#define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 181#define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 182#define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 183#define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 184#define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 185#define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 186 187struct device; 188struct signal_struct; 189 190/* 191 * Port level information. Each device keeps its own port level information 192 * so provide a common structure for those ports wanting to use common support 193 * routines. 194 * 195 * The tty port has a different lifetime to the tty so must be kept apart. 196 * In addition be careful as tty -> port mappings are valid for the life 197 * of the tty object but in many cases port -> tty mappings are valid only 198 * until a hangup so don't use the wrong path. 199 */ 200 201struct tty_port; 202 203struct tty_port_operations { 204 /* Return 1 if the carrier is raised */ 205 int (*carrier_raised)(struct tty_port *port); 206 /* Control the DTR line */ 207 void (*dtr_rts)(struct tty_port *port, int raise); 208 /* Called when the last close completes or a hangup finishes 209 IFF the port was initialized. Do not use to free resources. Called 210 under the port mutex to serialize against activate/shutdowns */ 211 void (*shutdown)(struct tty_port *port); 212 /* Called under the port mutex from tty_port_open, serialized using 213 the port mutex */ 214 /* FIXME: long term getting the tty argument *out* of this would be 215 good for consoles */ 216 int (*activate)(struct tty_port *port, struct tty_struct *tty); 217 /* Called on the final put of a port */ 218 void (*destruct)(struct tty_port *port); 219}; 220 221struct tty_port { 222 struct tty_bufhead buf; /* Locked internally */ 223 struct tty_struct *tty; /* Back pointer */ 224 struct tty_struct *itty; /* internal back ptr */ 225 const struct tty_port_operations *ops; /* Port operations */ 226 spinlock_t lock; /* Lock protecting tty field */ 227 int blocked_open; /* Waiting to open */ 228 int count; /* Usage count */ 229 wait_queue_head_t open_wait; /* Open waiters */ 230 wait_queue_head_t delta_msr_wait; /* Modem status change */ 231 unsigned long flags; /* TTY flags ASY_*/ 232 unsigned char console:1, /* port is a console */ 233 low_latency:1; /* optional: tune for latency */ 234 struct mutex mutex; /* Locking */ 235 struct mutex buf_mutex; /* Buffer alloc lock */ 236 unsigned char *xmit_buf; /* Optional buffer */ 237 unsigned int close_delay; /* Close port delay */ 238 unsigned int closing_wait; /* Delay for output */ 239 int drain_delay; /* Set to zero if no pure time 240 based drain is needed else 241 set to size of fifo */ 242 struct kref kref; /* Ref counter */ 243}; 244 245/* 246 * Where all of the state associated with a tty is kept while the tty 247 * is open. Since the termios state should be kept even if the tty 248 * has been closed --- for things like the baud rate, etc --- it is 249 * not stored here, but rather a pointer to the real state is stored 250 * here. Possible the winsize structure should have the same 251 * treatment, but (1) the default 80x24 is usually right and (2) it's 252 * most often used by a windowing system, which will set the correct 253 * size each time the window is created or resized anyway. 254 * - TYT, 9/14/92 255 */ 256 257struct tty_operations; 258 259struct tty_struct { 260 int magic; 261 struct kref kref; 262 struct device *dev; 263 struct tty_driver *driver; 264 const struct tty_operations *ops; 265 int index; 266 267 /* Protects ldisc changes: Lock tty not pty */ 268 struct ld_semaphore ldisc_sem; 269 struct tty_ldisc *ldisc; 270 271 struct mutex atomic_write_lock; 272 struct mutex legacy_mutex; 273 struct mutex throttle_mutex; 274 struct rw_semaphore termios_rwsem; 275 struct mutex winsize_mutex; 276 spinlock_t ctrl_lock; 277 spinlock_t flow_lock; 278 /* Termios values are protected by the termios rwsem */ 279 struct ktermios termios, termios_locked; 280 struct termiox *termiox; /* May be NULL for unsupported */ 281 char name[64]; 282 struct pid *pgrp; /* Protected by ctrl lock */ 283 struct pid *session; 284 unsigned long flags; 285 int count; 286 struct winsize winsize; /* winsize_mutex */ 287 unsigned long stopped:1, /* flow_lock */ 288 flow_stopped:1, 289 unused:BITS_PER_LONG - 2; 290 int hw_stopped; 291 unsigned long ctrl_status:8, /* ctrl_lock */ 292 packet:1, 293 unused_ctrl:BITS_PER_LONG - 9; 294 unsigned int receive_room; /* Bytes free for queue */ 295 int flow_change; 296 297 struct tty_struct *link; 298 struct fasync_struct *fasync; 299 int alt_speed; /* For magic substitution of 38400 bps */ 300 wait_queue_head_t write_wait; 301 wait_queue_head_t read_wait; 302 struct work_struct hangup_work; 303 void *disc_data; 304 void *driver_data; 305 spinlock_t files_lock; /* protects tty_files list */ 306 struct list_head tty_files; 307 308#define N_TTY_BUF_SIZE 4096 309 310 int closing; 311 unsigned char *write_buf; 312 int write_cnt; 313 /* If the tty has a pending do_SAK, queue it here - akpm */ 314 struct work_struct SAK_work; 315 struct tty_port *port; 316}; 317 318/* Each of a tty's open files has private_data pointing to tty_file_private */ 319struct tty_file_private { 320 struct tty_struct *tty; 321 struct file *file; 322 struct list_head list; 323}; 324 325/* tty magic number */ 326#define TTY_MAGIC 0x5401 327 328/* 329 * These bits are used in the flags field of the tty structure. 330 * 331 * So that interrupts won't be able to mess up the queues, 332 * copy_to_cooked must be atomic with respect to itself, as must 333 * tty->write. Thus, you must use the inline functions set_bit() and 334 * clear_bit() to make things atomic. 335 */ 336#define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 337#define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 338#define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 339#define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 340#define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 341#define TTY_OTHER_DONE 6 /* Closed pty has completed input processing */ 342#define TTY_LDISC_OPEN 11 /* Line discipline is open */ 343#define TTY_PTY_LOCK 16 /* pty private */ 344#define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 345#define TTY_HUPPED 18 /* Post driver->hangup() */ 346#define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 347 348/* Values for tty->flow_change */ 349#define TTY_THROTTLE_SAFE 1 350#define TTY_UNTHROTTLE_SAFE 2 351 352static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 353{ 354 tty->flow_change = val; 355} 356 357static inline void tty_set_flow_change(struct tty_struct *tty, int val) 358{ 359 tty->flow_change = val; 360 smp_mb(); 361} 362 363#ifdef CONFIG_TTY 364extern void console_init(void); 365extern void tty_kref_put(struct tty_struct *tty); 366extern struct pid *tty_get_pgrp(struct tty_struct *tty); 367extern void tty_vhangup_self(void); 368extern void disassociate_ctty(int priv); 369extern dev_t tty_devnum(struct tty_struct *tty); 370extern void proc_clear_tty(struct task_struct *p); 371extern struct tty_struct *get_current_tty(void); 372/* tty_io.c */ 373extern int __init tty_init(void); 374#else 375static inline void console_init(void) 376{ } 377static inline void tty_kref_put(struct tty_struct *tty) 378{ } 379static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 380{ return NULL; } 381static inline void tty_vhangup_self(void) 382{ } 383static inline void disassociate_ctty(int priv) 384{ } 385static inline dev_t tty_devnum(struct tty_struct *tty) 386{ return 0; } 387static inline void proc_clear_tty(struct task_struct *p) 388{ } 389static inline struct tty_struct *get_current_tty(void) 390{ return NULL; } 391/* tty_io.c */ 392static inline int __init tty_init(void) 393{ return 0; } 394#endif 395 396extern struct ktermios tty_std_termios; 397 398extern int vcs_init(void); 399 400extern struct class *tty_class; 401 402/** 403 * tty_kref_get - get a tty reference 404 * @tty: tty device 405 * 406 * Return a new reference to a tty object. The caller must hold 407 * sufficient locks/counts to ensure that their existing reference cannot 408 * go away 409 */ 410 411static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 412{ 413 if (tty) 414 kref_get(&tty->kref); 415 return tty; 416} 417 418extern const char *tty_name(const struct tty_struct *tty); 419extern const char *tty_driver_name(const struct tty_struct *tty); 420extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 421extern int __tty_check_change(struct tty_struct *tty, int sig); 422extern int tty_check_change(struct tty_struct *tty); 423extern void __stop_tty(struct tty_struct *tty); 424extern void stop_tty(struct tty_struct *tty); 425extern void __start_tty(struct tty_struct *tty); 426extern void start_tty(struct tty_struct *tty); 427extern int tty_register_driver(struct tty_driver *driver); 428extern int tty_unregister_driver(struct tty_driver *driver); 429extern struct device *tty_register_device(struct tty_driver *driver, 430 unsigned index, struct device *dev); 431extern struct device *tty_register_device_attr(struct tty_driver *driver, 432 unsigned index, struct device *device, 433 void *drvdata, 434 const struct attribute_group **attr_grp); 435extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 436extern void tty_write_message(struct tty_struct *tty, char *msg); 437extern int tty_send_xchar(struct tty_struct *tty, char ch); 438extern int tty_put_char(struct tty_struct *tty, unsigned char c); 439extern int tty_chars_in_buffer(struct tty_struct *tty); 440extern int tty_write_room(struct tty_struct *tty); 441extern void tty_driver_flush_buffer(struct tty_struct *tty); 442extern void tty_throttle(struct tty_struct *tty); 443extern void tty_unthrottle(struct tty_struct *tty); 444extern int tty_throttle_safe(struct tty_struct *tty); 445extern int tty_unthrottle_safe(struct tty_struct *tty); 446extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 447extern int is_current_pgrp_orphaned(void); 448extern void tty_hangup(struct tty_struct *tty); 449extern void tty_vhangup(struct tty_struct *tty); 450extern int tty_hung_up_p(struct file *filp); 451extern void do_SAK(struct tty_struct *tty); 452extern void __do_SAK(struct tty_struct *tty); 453extern void no_tty(void); 454extern void tty_buffer_free_all(struct tty_port *port); 455extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); 456extern void tty_buffer_init(struct tty_port *port); 457extern void tty_buffer_set_lock_subclass(struct tty_port *port); 458extern bool tty_buffer_restart_work(struct tty_port *port); 459extern bool tty_buffer_cancel_work(struct tty_port *port); 460extern speed_t tty_termios_baud_rate(struct ktermios *termios); 461extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 462extern void tty_termios_encode_baud_rate(struct ktermios *termios, 463 speed_t ibaud, speed_t obaud); 464extern void tty_encode_baud_rate(struct tty_struct *tty, 465 speed_t ibaud, speed_t obaud); 466 467/** 468 * tty_get_baud_rate - get tty bit rates 469 * @tty: tty to query 470 * 471 * Returns the baud rate as an integer for this terminal. The 472 * termios lock must be held by the caller and the terminal bit 473 * flags may be updated. 474 * 475 * Locking: none 476 */ 477static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 478{ 479 return tty_termios_baud_rate(&tty->termios); 480} 481 482extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 483extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 484extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 485 486extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 487extern void tty_ldisc_deref(struct tty_ldisc *); 488extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 489extern void tty_ldisc_hangup(struct tty_struct *tty, bool reset); 490extern int tty_ldisc_reinit(struct tty_struct *tty, int disc); 491extern const struct file_operations tty_ldiscs_proc_fops; 492 493extern void tty_wakeup(struct tty_struct *tty); 494extern void tty_ldisc_flush(struct tty_struct *tty); 495 496extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 497extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 498 unsigned int cmd, unsigned long arg); 499extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 500extern void tty_default_fops(struct file_operations *fops); 501extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); 502extern int tty_alloc_file(struct file *file); 503extern void tty_add_file(struct tty_struct *tty, struct file *file); 504extern void tty_free_file(struct file *file); 505extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 506extern int tty_release(struct inode *inode, struct file *filp); 507extern void tty_init_termios(struct tty_struct *tty); 508extern int tty_standard_install(struct tty_driver *driver, 509 struct tty_struct *tty); 510 511extern struct mutex tty_mutex; 512 513#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 514 515extern void tty_port_init(struct tty_port *port); 516extern void tty_port_link_device(struct tty_port *port, 517 struct tty_driver *driver, unsigned index); 518extern struct device *tty_port_register_device(struct tty_port *port, 519 struct tty_driver *driver, unsigned index, 520 struct device *device); 521extern struct device *tty_port_register_device_attr(struct tty_port *port, 522 struct tty_driver *driver, unsigned index, 523 struct device *device, void *drvdata, 524 const struct attribute_group **attr_grp); 525extern int tty_port_alloc_xmit_buf(struct tty_port *port); 526extern void tty_port_free_xmit_buf(struct tty_port *port); 527extern void tty_port_destroy(struct tty_port *port); 528extern void tty_port_put(struct tty_port *port); 529 530static inline struct tty_port *tty_port_get(struct tty_port *port) 531{ 532 if (port && kref_get_unless_zero(&port->kref)) 533 return port; 534 return NULL; 535} 536 537/* If the cts flow control is enabled, return true. */ 538static inline bool tty_port_cts_enabled(struct tty_port *port) 539{ 540 return port->flags & ASYNC_CTS_FLOW; 541} 542 543extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 544extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 545extern int tty_port_carrier_raised(struct tty_port *port); 546extern void tty_port_raise_dtr_rts(struct tty_port *port); 547extern void tty_port_lower_dtr_rts(struct tty_port *port); 548extern void tty_port_hangup(struct tty_port *port); 549extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 550extern void tty_port_tty_wakeup(struct tty_port *port); 551extern int tty_port_block_til_ready(struct tty_port *port, 552 struct tty_struct *tty, struct file *filp); 553extern int tty_port_close_start(struct tty_port *port, 554 struct tty_struct *tty, struct file *filp); 555extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 556extern void tty_port_close(struct tty_port *port, 557 struct tty_struct *tty, struct file *filp); 558extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 559 struct tty_struct *tty); 560extern int tty_port_open(struct tty_port *port, 561 struct tty_struct *tty, struct file *filp); 562static inline int tty_port_users(struct tty_port *port) 563{ 564 return port->count + port->blocked_open; 565} 566 567extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 568extern int tty_unregister_ldisc(int disc); 569extern int tty_set_ldisc(struct tty_struct *tty, int disc); 570extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 571extern void tty_ldisc_release(struct tty_struct *tty); 572extern void tty_ldisc_init(struct tty_struct *tty); 573extern void tty_ldisc_deinit(struct tty_struct *tty); 574extern int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 575 char *f, int count); 576 577/* n_tty.c */ 578extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 579extern void __init n_tty_init(void); 580 581/* tty_audit.c */ 582#ifdef CONFIG_AUDIT 583extern void tty_audit_add_data(struct tty_struct *tty, const void *data, 584 size_t size); 585extern void tty_audit_exit(void); 586extern void tty_audit_fork(struct signal_struct *sig); 587extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 588extern int tty_audit_push(void); 589#else 590static inline void tty_audit_add_data(struct tty_struct *tty, const void *data, 591 size_t size) 592{ 593} 594static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 595{ 596} 597static inline void tty_audit_exit(void) 598{ 599} 600static inline void tty_audit_fork(struct signal_struct *sig) 601{ 602} 603static inline int tty_audit_push(void) 604{ 605 return 0; 606} 607#endif 608 609/* tty_ioctl.c */ 610extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 611 unsigned int cmd, unsigned long arg); 612extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 613 unsigned int cmd, unsigned long arg); 614 615/* vt.c */ 616 617extern int vt_ioctl(struct tty_struct *tty, 618 unsigned int cmd, unsigned long arg); 619 620extern long vt_compat_ioctl(struct tty_struct *tty, 621 unsigned int cmd, unsigned long arg); 622 623/* tty_mutex.c */ 624/* functions for preparation of BKL removal */ 625extern void tty_lock(struct tty_struct *tty); 626extern int tty_lock_interruptible(struct tty_struct *tty); 627extern void tty_unlock(struct tty_struct *tty); 628extern void tty_lock_slave(struct tty_struct *tty); 629extern void tty_unlock_slave(struct tty_struct *tty); 630extern void tty_set_lock_subclass(struct tty_struct *tty); 631 632#ifdef CONFIG_PROC_FS 633extern void proc_tty_register_driver(struct tty_driver *); 634extern void proc_tty_unregister_driver(struct tty_driver *); 635#else 636static inline void proc_tty_register_driver(struct tty_driver *d) {} 637static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 638#endif 639 640#define tty_msg(fn, tty, f, ...) \ 641 fn("%s %s: " f, tty_driver_name(tty), tty_name(tty), ##__VA_ARGS__) 642 643#define tty_debug(tty, f, ...) tty_msg(pr_debug, tty, f, ##__VA_ARGS__) 644#define tty_info(tty, f, ...) tty_msg(pr_info, tty, f, ##__VA_ARGS__) 645#define tty_notice(tty, f, ...) tty_msg(pr_notice, tty, f, ##__VA_ARGS__) 646#define tty_warn(tty, f, ...) tty_msg(pr_warn, tty, f, ##__VA_ARGS__) 647#define tty_err(tty, f, ...) tty_msg(pr_err, tty, f, ##__VA_ARGS__) 648 649#define tty_info_ratelimited(tty, f, ...) \ 650 tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__) 651 652#endif