tty.h revision 40d5e0905a03601d40cd4e46b8690093c2355d03
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/* 19 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are 20 * hardcoded at present.) 21 */ 22#define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ 23#define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ 24#define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ 25 26/* 27 * This character is the same as _POSIX_VDISABLE: it cannot be used as 28 * a c_cc[] character, but indicates that a particular special character 29 * isn't in use (eg VINTR has no character etc) 30 */ 31#define __DISABLED_CHAR '\0' 32 33struct tty_buffer { 34 union { 35 struct tty_buffer *next; 36 struct llist_node free; 37 }; 38 int used; 39 int size; 40 int commit; 41 int read; 42 /* Data points here */ 43 unsigned long data[0]; 44}; 45 46static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) 47{ 48 return ((unsigned char *)b->data) + ofs; 49} 50 51static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) 52{ 53 return (char *)char_buf_ptr(b, ofs) + b->size; 54} 55 56struct tty_bufhead { 57 struct tty_buffer *head; /* Queue head */ 58 struct work_struct work; 59 struct mutex lock; 60 atomic_t priority; 61 struct tty_buffer sentinel; 62 struct llist_head free; /* Free queue head */ 63 atomic_t memory_used; /* In-use buffers excluding free list */ 64 struct tty_buffer *tail; /* Active buffer */ 65}; 66/* 67 * When a break, frame error, or parity error happens, these codes are 68 * stuffed into the flags buffer. 69 */ 70#define TTY_NORMAL 0 71#define TTY_BREAK 1 72#define TTY_FRAME 2 73#define TTY_PARITY 3 74#define TTY_OVERRUN 4 75 76#define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) 77#define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) 78#define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) 79#define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) 80#define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) 81#define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) 82#define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) 83#define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) 84#define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) 85#define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) 86#define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) 87#define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) 88#define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) 89#define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) 90#define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) 91#define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) 92#define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) 93 94#define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) 95#define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) 96#define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) 97#define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) 98 99#define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) 100#define I_BRKINT(tty) _I_FLAG((tty), BRKINT) 101#define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) 102#define I_PARMRK(tty) _I_FLAG((tty), PARMRK) 103#define I_INPCK(tty) _I_FLAG((tty), INPCK) 104#define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) 105#define I_INLCR(tty) _I_FLAG((tty), INLCR) 106#define I_IGNCR(tty) _I_FLAG((tty), IGNCR) 107#define I_ICRNL(tty) _I_FLAG((tty), ICRNL) 108#define I_IUCLC(tty) _I_FLAG((tty), IUCLC) 109#define I_IXON(tty) _I_FLAG((tty), IXON) 110#define I_IXANY(tty) _I_FLAG((tty), IXANY) 111#define I_IXOFF(tty) _I_FLAG((tty), IXOFF) 112#define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) 113#define I_IUTF8(tty) _I_FLAG((tty), IUTF8) 114 115#define O_OPOST(tty) _O_FLAG((tty), OPOST) 116#define O_OLCUC(tty) _O_FLAG((tty), OLCUC) 117#define O_ONLCR(tty) _O_FLAG((tty), ONLCR) 118#define O_OCRNL(tty) _O_FLAG((tty), OCRNL) 119#define O_ONOCR(tty) _O_FLAG((tty), ONOCR) 120#define O_ONLRET(tty) _O_FLAG((tty), ONLRET) 121#define O_OFILL(tty) _O_FLAG((tty), OFILL) 122#define O_OFDEL(tty) _O_FLAG((tty), OFDEL) 123#define O_NLDLY(tty) _O_FLAG((tty), NLDLY) 124#define O_CRDLY(tty) _O_FLAG((tty), CRDLY) 125#define O_TABDLY(tty) _O_FLAG((tty), TABDLY) 126#define O_BSDLY(tty) _O_FLAG((tty), BSDLY) 127#define O_VTDLY(tty) _O_FLAG((tty), VTDLY) 128#define O_FFDLY(tty) _O_FLAG((tty), FFDLY) 129 130#define C_BAUD(tty) _C_FLAG((tty), CBAUD) 131#define C_CSIZE(tty) _C_FLAG((tty), CSIZE) 132#define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) 133#define C_CREAD(tty) _C_FLAG((tty), CREAD) 134#define C_PARENB(tty) _C_FLAG((tty), PARENB) 135#define C_PARODD(tty) _C_FLAG((tty), PARODD) 136#define C_HUPCL(tty) _C_FLAG((tty), HUPCL) 137#define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) 138#define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) 139#define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) 140 141#define L_ISIG(tty) _L_FLAG((tty), ISIG) 142#define L_ICANON(tty) _L_FLAG((tty), ICANON) 143#define L_XCASE(tty) _L_FLAG((tty), XCASE) 144#define L_ECHO(tty) _L_FLAG((tty), ECHO) 145#define L_ECHOE(tty) _L_FLAG((tty), ECHOE) 146#define L_ECHOK(tty) _L_FLAG((tty), ECHOK) 147#define L_ECHONL(tty) _L_FLAG((tty), ECHONL) 148#define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) 149#define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) 150#define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) 151#define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) 152#define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) 153#define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) 154#define L_PENDIN(tty) _L_FLAG((tty), PENDIN) 155#define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) 156#define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) 157 158struct device; 159struct signal_struct; 160 161/* 162 * Port level information. Each device keeps its own port level information 163 * so provide a common structure for those ports wanting to use common support 164 * routines. 165 * 166 * The tty port has a different lifetime to the tty so must be kept apart. 167 * In addition be careful as tty -> port mappings are valid for the life 168 * of the tty object but in many cases port -> tty mappings are valid only 169 * until a hangup so don't use the wrong path. 170 */ 171 172struct tty_port; 173 174struct tty_port_operations { 175 /* Return 1 if the carrier is raised */ 176 int (*carrier_raised)(struct tty_port *port); 177 /* Control the DTR line */ 178 void (*dtr_rts)(struct tty_port *port, int raise); 179 /* Called when the last close completes or a hangup finishes 180 IFF the port was initialized. Do not use to free resources. Called 181 under the port mutex to serialize against activate/shutdowns */ 182 void (*shutdown)(struct tty_port *port); 183 void (*drop)(struct tty_port *port); 184 /* Called under the port mutex from tty_port_open, serialized using 185 the port mutex */ 186 /* FIXME: long term getting the tty argument *out* of this would be 187 good for consoles */ 188 int (*activate)(struct tty_port *port, struct tty_struct *tty); 189 /* Called on the final put of a port */ 190 void (*destruct)(struct tty_port *port); 191}; 192 193struct tty_port { 194 struct tty_bufhead buf; /* Locked internally */ 195 struct tty_struct *tty; /* Back pointer */ 196 struct tty_struct *itty; /* internal back ptr */ 197 const struct tty_port_operations *ops; /* Port operations */ 198 spinlock_t lock; /* Lock protecting tty field */ 199 int blocked_open; /* Waiting to open */ 200 int count; /* Usage count */ 201 wait_queue_head_t open_wait; /* Open waiters */ 202 wait_queue_head_t close_wait; /* Close waiters */ 203 wait_queue_head_t delta_msr_wait; /* Modem status change */ 204 unsigned long flags; /* TTY flags ASY_*/ 205 unsigned char console:1, /* port is a console */ 206 low_latency:1; /* direct buffer flush */ 207 struct mutex mutex; /* Locking */ 208 struct mutex buf_mutex; /* Buffer alloc lock */ 209 unsigned char *xmit_buf; /* Optional buffer */ 210 unsigned int close_delay; /* Close port delay */ 211 unsigned int closing_wait; /* Delay for output */ 212 int drain_delay; /* Set to zero if no pure time 213 based drain is needed else 214 set to size of fifo */ 215 struct kref kref; /* Ref counter */ 216}; 217 218/* 219 * Where all of the state associated with a tty is kept while the tty 220 * is open. Since the termios state should be kept even if the tty 221 * has been closed --- for things like the baud rate, etc --- it is 222 * not stored here, but rather a pointer to the real state is stored 223 * here. Possible the winsize structure should have the same 224 * treatment, but (1) the default 80x24 is usually right and (2) it's 225 * most often used by a windowing system, which will set the correct 226 * size each time the window is created or resized anyway. 227 * - TYT, 9/14/92 228 */ 229 230struct tty_operations; 231 232struct tty_struct { 233 int magic; 234 struct kref kref; 235 struct device *dev; 236 struct tty_driver *driver; 237 const struct tty_operations *ops; 238 int index; 239 240 /* Protects ldisc changes: Lock tty not pty */ 241 struct ld_semaphore ldisc_sem; 242 struct tty_ldisc *ldisc; 243 244 struct mutex atomic_write_lock; 245 struct mutex legacy_mutex; 246 struct mutex throttle_mutex; 247 struct rw_semaphore termios_rwsem; 248 spinlock_t ctrl_lock; 249 /* Termios values are protected by the termios rwsem */ 250 struct ktermios termios, termios_locked; 251 struct termiox *termiox; /* May be NULL for unsupported */ 252 char name[64]; 253 struct pid *pgrp; /* Protected by ctrl lock */ 254 struct pid *session; 255 unsigned long flags; 256 int count; 257 struct winsize winsize; /* termios rwsem */ 258 unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1; 259 unsigned char ctrl_status; /* ctrl_lock */ 260 unsigned int receive_room; /* Bytes free for queue */ 261 int flow_change; 262 263 struct tty_struct *link; 264 struct fasync_struct *fasync; 265 int alt_speed; /* For magic substitution of 38400 bps */ 266 wait_queue_head_t write_wait; 267 wait_queue_head_t read_wait; 268 struct work_struct hangup_work; 269 void *disc_data; 270 void *driver_data; 271 struct list_head tty_files; 272 273#define N_TTY_BUF_SIZE 4096 274 275 unsigned char closing:1; 276 unsigned char *write_buf; 277 int write_cnt; 278 /* If the tty has a pending do_SAK, queue it here - akpm */ 279 struct work_struct SAK_work; 280 struct tty_port *port; 281}; 282 283/* Each of a tty's open files has private_data pointing to tty_file_private */ 284struct tty_file_private { 285 struct tty_struct *tty; 286 struct file *file; 287 struct list_head list; 288}; 289 290/* tty magic number */ 291#define TTY_MAGIC 0x5401 292 293/* 294 * These bits are used in the flags field of the tty structure. 295 * 296 * So that interrupts won't be able to mess up the queues, 297 * copy_to_cooked must be atomic with respect to itself, as must 298 * tty->write. Thus, you must use the inline functions set_bit() and 299 * clear_bit() to make things atomic. 300 */ 301#define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ 302#define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ 303#define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ 304#define TTY_EXCLUSIVE 3 /* Exclusive open mode */ 305#define TTY_DEBUG 4 /* Debugging */ 306#define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ 307#define TTY_CLOSING 7 /* ->close() in progress */ 308#define TTY_LDISC_OPEN 11 /* Line discipline is open */ 309#define TTY_PTY_LOCK 16 /* pty private */ 310#define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ 311#define TTY_HUPPED 18 /* Post driver->hangup() */ 312#define TTY_HUPPING 21 /* ->hangup() in progress */ 313#define TTY_LDISC_HALTED 22 /* Line discipline is halted */ 314 315#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) 316 317/* Values for tty->flow_change */ 318#define TTY_THROTTLE_SAFE 1 319#define TTY_UNTHROTTLE_SAFE 2 320 321static inline void __tty_set_flow_change(struct tty_struct *tty, int val) 322{ 323 tty->flow_change = val; 324} 325 326static inline void tty_set_flow_change(struct tty_struct *tty, int val) 327{ 328 tty->flow_change = val; 329 smp_mb(); 330} 331 332#ifdef CONFIG_TTY 333extern void console_init(void); 334extern void tty_kref_put(struct tty_struct *tty); 335extern struct pid *tty_get_pgrp(struct tty_struct *tty); 336extern void tty_vhangup_self(void); 337extern void disassociate_ctty(int priv); 338extern dev_t tty_devnum(struct tty_struct *tty); 339extern void proc_clear_tty(struct task_struct *p); 340extern struct tty_struct *get_current_tty(void); 341/* tty_io.c */ 342extern int __init tty_init(void); 343#else 344static inline void console_init(void) 345{ } 346static inline void tty_kref_put(struct tty_struct *tty) 347{ } 348static inline struct pid *tty_get_pgrp(struct tty_struct *tty) 349{ return NULL; } 350static inline void tty_vhangup_self(void) 351{ } 352static inline void disassociate_ctty(int priv) 353{ } 354static inline dev_t tty_devnum(struct tty_struct *tty) 355{ return 0; } 356static inline void proc_clear_tty(struct task_struct *p) 357{ } 358static inline struct tty_struct *get_current_tty(void) 359{ return NULL; } 360/* tty_io.c */ 361static inline int __init tty_init(void) 362{ return 0; } 363#endif 364 365extern void tty_write_flush(struct tty_struct *); 366 367extern struct ktermios tty_std_termios; 368 369extern int vcs_init(void); 370 371extern struct class *tty_class; 372 373/** 374 * tty_kref_get - get a tty reference 375 * @tty: tty device 376 * 377 * Return a new reference to a tty object. The caller must hold 378 * sufficient locks/counts to ensure that their existing reference cannot 379 * go away 380 */ 381 382static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) 383{ 384 if (tty) 385 kref_get(&tty->kref); 386 return tty; 387} 388 389extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, 390 const char *routine); 391extern char *tty_name(struct tty_struct *tty, char *buf); 392extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); 393extern int tty_check_change(struct tty_struct *tty); 394extern void stop_tty(struct tty_struct *tty); 395extern void start_tty(struct tty_struct *tty); 396extern int tty_register_driver(struct tty_driver *driver); 397extern int tty_unregister_driver(struct tty_driver *driver); 398extern struct device *tty_register_device(struct tty_driver *driver, 399 unsigned index, struct device *dev); 400extern struct device *tty_register_device_attr(struct tty_driver *driver, 401 unsigned index, struct device *device, 402 void *drvdata, 403 const struct attribute_group **attr_grp); 404extern void tty_unregister_device(struct tty_driver *driver, unsigned index); 405extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, 406 int buflen); 407extern void tty_write_message(struct tty_struct *tty, char *msg); 408extern int tty_put_char(struct tty_struct *tty, unsigned char c); 409extern int tty_chars_in_buffer(struct tty_struct *tty); 410extern int tty_write_room(struct tty_struct *tty); 411extern void tty_driver_flush_buffer(struct tty_struct *tty); 412extern void tty_throttle(struct tty_struct *tty); 413extern void tty_unthrottle(struct tty_struct *tty); 414extern int tty_throttle_safe(struct tty_struct *tty); 415extern int tty_unthrottle_safe(struct tty_struct *tty); 416extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); 417extern void tty_driver_remove_tty(struct tty_driver *driver, 418 struct tty_struct *tty); 419extern void tty_free_termios(struct tty_struct *tty); 420extern int is_current_pgrp_orphaned(void); 421extern int is_ignored(int sig); 422extern int tty_signal(int sig, struct tty_struct *tty); 423extern void tty_hangup(struct tty_struct *tty); 424extern void tty_vhangup(struct tty_struct *tty); 425extern void tty_vhangup_locked(struct tty_struct *tty); 426extern void tty_unhangup(struct file *filp); 427extern int tty_hung_up_p(struct file *filp); 428extern void do_SAK(struct tty_struct *tty); 429extern void __do_SAK(struct tty_struct *tty); 430extern void no_tty(void); 431extern void tty_flush_to_ldisc(struct tty_struct *tty); 432extern void tty_buffer_free_all(struct tty_port *port); 433extern void tty_buffer_flush(struct tty_struct *tty); 434extern void tty_buffer_init(struct tty_port *port); 435extern speed_t tty_termios_baud_rate(struct ktermios *termios); 436extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); 437extern void tty_termios_encode_baud_rate(struct ktermios *termios, 438 speed_t ibaud, speed_t obaud); 439extern void tty_encode_baud_rate(struct tty_struct *tty, 440 speed_t ibaud, speed_t obaud); 441 442/** 443 * tty_get_baud_rate - get tty bit rates 444 * @tty: tty to query 445 * 446 * Returns the baud rate as an integer for this terminal. The 447 * termios lock must be held by the caller and the terminal bit 448 * flags may be updated. 449 * 450 * Locking: none 451 */ 452static inline speed_t tty_get_baud_rate(struct tty_struct *tty) 453{ 454 return tty_termios_baud_rate(&tty->termios); 455} 456 457extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); 458extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); 459extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); 460 461extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); 462extern void tty_ldisc_deref(struct tty_ldisc *); 463extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); 464extern void tty_ldisc_hangup(struct tty_struct *tty); 465extern const struct file_operations tty_ldiscs_proc_fops; 466 467extern void tty_wakeup(struct tty_struct *tty); 468extern void tty_ldisc_flush(struct tty_struct *tty); 469 470extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); 471extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, 472 unsigned int cmd, unsigned long arg); 473extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); 474extern void tty_default_fops(struct file_operations *fops); 475extern struct tty_struct *alloc_tty_struct(void); 476extern int tty_alloc_file(struct file *file); 477extern void tty_add_file(struct tty_struct *tty, struct file *file); 478extern void tty_free_file(struct file *file); 479extern void free_tty_struct(struct tty_struct *tty); 480extern void initialize_tty_struct(struct tty_struct *tty, 481 struct tty_driver *driver, int idx); 482extern void deinitialize_tty_struct(struct tty_struct *tty); 483extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); 484extern int tty_release(struct inode *inode, struct file *filp); 485extern int tty_init_termios(struct tty_struct *tty); 486extern int tty_standard_install(struct tty_driver *driver, 487 struct tty_struct *tty); 488 489extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty); 490extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty); 491 492extern struct mutex tty_mutex; 493extern spinlock_t tty_files_lock; 494 495extern void tty_write_unlock(struct tty_struct *tty); 496extern int tty_write_lock(struct tty_struct *tty, int ndelay); 497#define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) 498 499extern void tty_port_init(struct tty_port *port); 500extern void tty_port_link_device(struct tty_port *port, 501 struct tty_driver *driver, unsigned index); 502extern struct device *tty_port_register_device(struct tty_port *port, 503 struct tty_driver *driver, unsigned index, 504 struct device *device); 505extern struct device *tty_port_register_device_attr(struct tty_port *port, 506 struct tty_driver *driver, unsigned index, 507 struct device *device, void *drvdata, 508 const struct attribute_group **attr_grp); 509extern int tty_port_alloc_xmit_buf(struct tty_port *port); 510extern void tty_port_free_xmit_buf(struct tty_port *port); 511extern void tty_port_destroy(struct tty_port *port); 512extern void tty_port_put(struct tty_port *port); 513 514static inline struct tty_port *tty_port_get(struct tty_port *port) 515{ 516 if (port) 517 kref_get(&port->kref); 518 return port; 519} 520 521/* If the cts flow control is enabled, return true. */ 522static inline bool tty_port_cts_enabled(struct tty_port *port) 523{ 524 return port->flags & ASYNC_CTS_FLOW; 525} 526 527extern struct tty_struct *tty_port_tty_get(struct tty_port *port); 528extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); 529extern int tty_port_carrier_raised(struct tty_port *port); 530extern void tty_port_raise_dtr_rts(struct tty_port *port); 531extern void tty_port_lower_dtr_rts(struct tty_port *port); 532extern void tty_port_hangup(struct tty_port *port); 533extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); 534extern void tty_port_tty_wakeup(struct tty_port *port); 535extern int tty_port_block_til_ready(struct tty_port *port, 536 struct tty_struct *tty, struct file *filp); 537extern int tty_port_close_start(struct tty_port *port, 538 struct tty_struct *tty, struct file *filp); 539extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); 540extern void tty_port_close(struct tty_port *port, 541 struct tty_struct *tty, struct file *filp); 542extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, 543 struct tty_struct *tty); 544extern int tty_port_open(struct tty_port *port, 545 struct tty_struct *tty, struct file *filp); 546static inline int tty_port_users(struct tty_port *port) 547{ 548 return port->count + port->blocked_open; 549} 550 551extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); 552extern int tty_unregister_ldisc(int disc); 553extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); 554extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); 555extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty); 556extern void tty_ldisc_init(struct tty_struct *tty); 557extern void tty_ldisc_deinit(struct tty_struct *tty); 558extern void tty_ldisc_begin(void); 559 560static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, 561 char *f, int count) 562{ 563 if (ld->ops->receive_buf2) 564 count = ld->ops->receive_buf2(ld->tty, p, f, count); 565 else { 566 count = min_t(int, count, ld->tty->receive_room); 567 if (count) 568 ld->ops->receive_buf(ld->tty, p, f, count); 569 } 570 return count; 571} 572 573 574/* n_tty.c */ 575extern struct tty_ldisc_ops tty_ldisc_N_TTY; 576extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); 577 578/* tty_audit.c */ 579#ifdef CONFIG_AUDIT 580extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, 581 size_t size, unsigned icanon); 582extern void tty_audit_exit(void); 583extern void tty_audit_fork(struct signal_struct *sig); 584extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); 585extern void tty_audit_push(struct tty_struct *tty); 586extern int tty_audit_push_current(void); 587#else 588static inline void tty_audit_add_data(struct tty_struct *tty, 589 unsigned char *data, size_t size, unsigned icanon) 590{ 591} 592static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) 593{ 594} 595static inline void tty_audit_exit(void) 596{ 597} 598static inline void tty_audit_fork(struct signal_struct *sig) 599{ 600} 601static inline void tty_audit_push(struct tty_struct *tty) 602{ 603} 604static inline int tty_audit_push_current(void) 605{ 606 return 0; 607} 608#endif 609 610/* tty_ioctl.c */ 611extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, 612 unsigned int cmd, unsigned long arg); 613extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, 614 unsigned int cmd, unsigned long arg); 615 616/* serial.c */ 617 618extern void serial_console_init(void); 619 620/* pcxx.c */ 621 622extern int pcxe_open(struct tty_struct *tty, struct file *filp); 623 624/* vt.c */ 625 626extern int vt_ioctl(struct tty_struct *tty, 627 unsigned int cmd, unsigned long arg); 628 629extern long vt_compat_ioctl(struct tty_struct *tty, 630 unsigned int cmd, unsigned long arg); 631 632/* tty_mutex.c */ 633/* functions for preparation of BKL removal */ 634extern void __lockfunc tty_lock(struct tty_struct *tty); 635extern void __lockfunc tty_unlock(struct tty_struct *tty); 636extern void __lockfunc tty_lock_pair(struct tty_struct *tty, 637 struct tty_struct *tty2); 638extern void __lockfunc tty_unlock_pair(struct tty_struct *tty, 639 struct tty_struct *tty2); 640 641/* 642 * this shall be called only from where BTM is held (like close) 643 * 644 * We need this to ensure nobody waits for us to finish while we are waiting. 645 * Without this we were encountering system stalls. 646 * 647 * This should be indeed removed with BTM removal later. 648 * 649 * Locking: BTM required. Nobody is allowed to hold port->mutex. 650 */ 651static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, 652 long timeout) 653{ 654 tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ 655 tty_wait_until_sent(tty, timeout); 656 tty_lock(tty); 657} 658 659/* 660 * wait_event_interruptible_tty -- wait for a condition with the tty lock held 661 * 662 * The condition we are waiting for might take a long time to 663 * become true, or might depend on another thread taking the 664 * BTM. In either case, we need to drop the BTM to guarantee 665 * forward progress. This is a leftover from the conversion 666 * from the BKL and should eventually get removed as the BTM 667 * falls out of use. 668 * 669 * Do not use in new code. 670 */ 671#define wait_event_interruptible_tty(tty, wq, condition) \ 672({ \ 673 int __ret = 0; \ 674 if (!(condition)) { \ 675 __wait_event_interruptible_tty(tty, wq, condition, __ret); \ 676 } \ 677 __ret; \ 678}) 679 680#define __wait_event_interruptible_tty(tty, wq, condition, ret) \ 681do { \ 682 DEFINE_WAIT(__wait); \ 683 \ 684 for (;;) { \ 685 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ 686 if (condition) \ 687 break; \ 688 if (!signal_pending(current)) { \ 689 tty_unlock(tty); \ 690 schedule(); \ 691 tty_lock(tty); \ 692 continue; \ 693 } \ 694 ret = -ERESTARTSYS; \ 695 break; \ 696 } \ 697 finish_wait(&wq, &__wait); \ 698} while (0) 699 700#ifdef CONFIG_PROC_FS 701extern void proc_tty_register_driver(struct tty_driver *); 702extern void proc_tty_unregister_driver(struct tty_driver *); 703#else 704static inline void proc_tty_register_driver(struct tty_driver *d) {} 705static inline void proc_tty_unregister_driver(struct tty_driver *d) {} 706#endif 707 708#endif 709