LXR linux/include/linux/tty.h

   1#ifndef _LINUX_TTY_H
   2#define _LINUX_TTY_H
   3
   4/*
   5 * 'tty.h' defines some structures used by tty_io.c and some defines.
   6 */
   7
   8#ifdef __KERNEL__
   9#include <linux/fs.h>
  10#include <linux/major.h>
  11#include <linux/termios.h>
  12#include <linux/workqueue.h>
  13#include <linux/tty_driver.h>
  14#include <linux/tty_ldisc.h>
  15#include <linux/mutex.h>
  16
  17#include <asm/system.h>
  18
  19
  20/*
  21 * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
  22 * hardcoded at present.)
  23 */
  24#define NR_UNIX98_PTY_DEFAULT   4096      /* Default maximum for Unix98 ptys */
  25#define NR_UNIX98_PTY_MAX       (1 << MINORBITS) /* Absolute limit */
  26#define NR_LDISCS               30
  27
  28/* line disciplines */
  29#define N_TTY           0
  30#define N_SLIP          1
  31#define N_MOUSE         2
  32#define N_PPP           3
  33#define N_STRIP         4
  34#define N_AX25          5
  35#define N_X25           6       /* X.25 async */
  36#define N_6PACK         7
  37#define N_MASC          8       /* Reserved for Mobitex module <kaz@cafe.net> */
  38#define N_R3964         9       /* Reserved for Simatic R3964 module */
  39#define N_PROFIBUS_FDL  10      /* Reserved for Profibus */
  40#define N_IRDA          11      /* Linux IrDa - http://irda.sourceforge.net/ */
  41#define N_SMSBLOCK      12      /* SMS block mode - for talking to GSM data */
  42                                /* cards about SMS messages */
  43#define N_HDLC          13      /* synchronous HDLC */
  44#define N_SYNC_PPP      14      /* synchronous PPP */
  45#define N_HCI           15      /* Bluetooth HCI UART */
  46#define N_GIGASET_M101  16      /* Siemens Gigaset M101 serial DECT adapter */
  47#define N_SLCAN         17      /* Serial / USB serial CAN Adaptors */
  48#define N_PPS           18      /* Pulse per Second */
  49#define N_V253          19      /* Codec control over voice modem */
  50#define N_CAIF          20      /* CAIF protocol for talking to modems */
  51#define N_GSM0710       21      /* GSM 0710 Mux */
  52
  53/*
  54 * This character is the same as _POSIX_VDISABLE: it cannot be used as
  55 * a c_cc[] character, but indicates that a particular special character
  56 * isn't in use (eg VINTR has no character etc)
  57 */
  58#define __DISABLED_CHAR '\0'
  59
  60struct tty_buffer {
  61        struct tty_buffer *next;
  62        char *char_buf_ptr;
  63        unsigned char *flag_buf_ptr;
  64        int used;
  65        int size;
  66        int commit;
  67        int read;
  68        /* Data points here */
  69        unsigned long data[0];
  70};
  71
  72/*
  73 * We default to dicing tty buffer allocations to this many characters
  74 * in order to avoid multiple page allocations. We know the size of
  75 * tty_buffer itself but it must also be taken into account that the
  76 * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
  77 * logic this must match
  78 */
  79
  80#define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
  81
  82
  83struct tty_bufhead {
  84        struct delayed_work work;
  85        spinlock_t lock;
  86        struct tty_buffer *head;        /* Queue head */
  87        struct tty_buffer *tail;        /* Active buffer */
  88        struct tty_buffer *free;        /* Free queue head */
  89        int memory_used;                /* Buffer space used excluding
  90                                                                free queue */
  91};
  92/*
  93 * When a break, frame error, or parity error happens, these codes are
  94 * stuffed into the flags buffer.
  95 */
  96#define TTY_NORMAL      0
  97#define TTY_BREAK       1
  98#define TTY_FRAME       2
  99#define TTY_PARITY      3
 100#define TTY_OVERRUN     4
 101
 102#define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
 103#define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
 104#define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
 105#define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
 106#define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
 107#define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
 108#define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
 109#define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
 110#define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
 111#define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
 112#define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
 113#define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
 114#define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
 115#define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
 116#define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
 117#define LNEXT_CHAR(tty) ((tty)->termios->c_cc[VLNEXT])
 118#define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
 119
 120#define _I_FLAG(tty, f) ((tty)->termios->c_iflag & (f))
 121#define _O_FLAG(tty, f) ((tty)->termios->c_oflag & (f))
 122#define _C_FLAG(tty, f) ((tty)->termios->c_cflag & (f))
 123#define _L_FLAG(tty, f) ((tty)->termios->c_lflag & (f))
 124
 125#define I_IGNBRK(tty)   _I_FLAG((tty), IGNBRK)
 126#define I_BRKINT(tty)   _I_FLAG((tty), BRKINT)
 127#define I_IGNPAR(tty)   _I_FLAG((tty), IGNPAR)
 128#define I_PARMRK(tty)   _I_FLAG((tty), PARMRK)
 129#define I_INPCK(tty)    _I_FLAG((tty), INPCK)
 130#define I_ISTRIP(tty)   _I_FLAG((tty), ISTRIP)
 131#define I_INLCR(tty)    _I_FLAG((tty), INLCR)
 132#define I_IGNCR(tty)    _I_FLAG((tty), IGNCR)
 133#define I_ICRNL(tty)    _I_FLAG((tty), ICRNL)
 134#define I_IUCLC(tty)    _I_FLAG((tty), IUCLC)
 135#define I_IXON(tty)     _I_FLAG((tty), IXON)
 136#define I_IXANY(tty)    _I_FLAG((tty), IXANY)
 137#define I_IXOFF(tty)    _I_FLAG((tty), IXOFF)
 138#define I_IMAXBEL(tty)  _I_FLAG((tty), IMAXBEL)
 139#define I_IUTF8(tty)    _I_FLAG((tty), IUTF8)
 140
 141#define O_OPOST(tty)    _O_FLAG((tty), OPOST)
 142#define O_OLCUC(tty)    _O_FLAG((tty), OLCUC)
 143#define O_ONLCR(tty)    _O_FLAG((tty), ONLCR)
 144#define O_OCRNL(tty)    _O_FLAG((tty), OCRNL)
 145#define O_ONOCR(tty)    _O_FLAG((tty), ONOCR)
 146#define O_ONLRET(tty)   _O_FLAG((tty), ONLRET)
 147#define O_OFILL(tty)    _O_FLAG((tty), OFILL)
 148#define O_OFDEL(tty)    _O_FLAG((tty), OFDEL)
 149#define O_NLDLY(tty)    _O_FLAG((tty), NLDLY)
 150#define O_CRDLY(tty)    _O_FLAG((tty), CRDLY)
 151#define O_TABDLY(tty)   _O_FLAG((tty), TABDLY)
 152#define O_BSDLY(tty)    _O_FLAG((tty), BSDLY)
 153#define O_VTDLY(tty)    _O_FLAG((tty), VTDLY)
 154#define O_FFDLY(tty)    _O_FLAG((tty), FFDLY)
 155
 156#define C_BAUD(tty)     _C_FLAG((tty), CBAUD)
 157#define C_CSIZE(tty)    _C_FLAG((tty), CSIZE)
 158#define C_CSTOPB(tty)   _C_FLAG((tty), CSTOPB)
 159#define C_CREAD(tty)    _C_FLAG((tty), CREAD)
 160#define C_PARENB(tty)   _C_FLAG((tty), PARENB)
 161#define C_PARODD(tty)   _C_FLAG((tty), PARODD)
 162#define C_HUPCL(tty)    _C_FLAG((tty), HUPCL)
 163#define C_CLOCAL(tty)   _C_FLAG((tty), CLOCAL)
 164#define C_CIBAUD(tty)   _C_FLAG((tty), CIBAUD)
 165#define C_CRTSCTS(tty)  _C_FLAG((tty), CRTSCTS)
 166
 167#define L_ISIG(tty)     _L_FLAG((tty), ISIG)
 168#define L_ICANON(tty)   _L_FLAG((tty), ICANON)
 169#define L_XCASE(tty)    _L_FLAG((tty), XCASE)
 170#define L_ECHO(tty)     _L_FLAG((tty), ECHO)
 171#define L_ECHOE(tty)    _L_FLAG((tty), ECHOE)
 172#define L_ECHOK(tty)    _L_FLAG((tty), ECHOK)
 173#define L_ECHONL(tty)   _L_FLAG((tty), ECHONL)
 174#define L_NOFLSH(tty)   _L_FLAG((tty), NOFLSH)
 175#define L_TOSTOP(tty)   _L_FLAG((tty), TOSTOP)
 176#define L_ECHOCTL(tty)  _L_FLAG((tty), ECHOCTL)
 177#define L_ECHOPRT(tty)  _L_FLAG((tty), ECHOPRT)
 178#define L_ECHOKE(tty)   _L_FLAG((tty), ECHOKE)
 179#define L_FLUSHO(tty)   _L_FLAG((tty), FLUSHO)
 180#define L_PENDIN(tty)   _L_FLAG((tty), PENDIN)
 181#define L_IEXTEN(tty)   _L_FLAG((tty), IEXTEN)
 182
 183struct device;
 184struct signal_struct;
 185
 186/*
 187 * Port level information. Each device keeps its own port level information
 188 * so provide a common structure for those ports wanting to use common support
 189 * routines.
 190 *
 191 * The tty port has a different lifetime to the tty so must be kept apart.
 192 * In addition be careful as tty -> port mappings are valid for the life
 193 * of the tty object but in many cases port -> tty mappings are valid only
 194 * until a hangup so don't use the wrong path.
 195 */
 196
 197struct tty_port;
 198
 199struct tty_port_operations {
 200        /* Return 1 if the carrier is raised */
 201        int (*carrier_raised)(struct tty_port *port);
 202        /* Control the DTR line */
 203        void (*dtr_rts)(struct tty_port *port, int raise);
 204        /* Called when the last close completes or a hangup finishes
 205           IFF the port was initialized. Do not use to free resources. Called
 206           under the port mutex to serialize against activate/shutdowns */
 207        void (*shutdown)(struct tty_port *port);
 208        void (*drop)(struct tty_port *port);
 209        /* Called under the port mutex from tty_port_open, serialized using
 210           the port mutex */
 211        /* FIXME: long term getting the tty argument *out* of this would be
 212           good for consoles */
 213        int (*activate)(struct tty_port *port, struct tty_struct *tty);
 214        /* Called on the final put of a port */
 215        void (*destruct)(struct tty_port *port);
 216};
 217        
 218struct tty_port {
 219        struct tty_struct       *tty;           /* Back pointer */
 220        const struct tty_port_operations *ops;  /* Port operations */
 221        spinlock_t              lock;           /* Lock protecting tty field */
 222        int                     blocked_open;   /* Waiting to open */
 223        int                     count;          /* Usage count */
 224        wait_queue_head_t       open_wait;      /* Open waiters */
 225        wait_queue_head_t       close_wait;     /* Close waiters */
 226        wait_queue_head_t       delta_msr_wait; /* Modem status change */
 227        unsigned long           flags;          /* TTY flags ASY_*/
 228        unsigned char           console:1;      /* port is a console */
 229        struct mutex            mutex;          /* Locking */
 230        struct mutex            buf_mutex;      /* Buffer alloc lock */
 231        unsigned char           *xmit_buf;      /* Optional buffer */
 232        unsigned int            close_delay;    /* Close port delay */
 233        unsigned int            closing_wait;   /* Delay for output */
 234        int                     drain_delay;    /* Set to zero if no pure time
 235                                                   based drain is needed else
 236                                                   set to size of fifo */
 237        struct kref             kref;           /* Ref counter */
 238};
 239
 240/*
 241 * Where all of the state associated with a tty is kept while the tty
 242 * is open.  Since the termios state should be kept even if the tty
 243 * has been closed --- for things like the baud rate, etc --- it is
 244 * not stored here, but rather a pointer to the real state is stored
 245 * here.  Possible the winsize structure should have the same
 246 * treatment, but (1) the default 80x24 is usually right and (2) it's
 247 * most often used by a windowing system, which will set the correct
 248 * size each time the window is created or resized anyway.
 249 *                                              - TYT, 9/14/92
 250 */
 251
 252struct tty_operations;
 253
 254struct tty_struct {
 255        int     magic;
 256        struct kref kref;
 257        struct tty_driver *driver;
 258        const struct tty_operations *ops;
 259        int index;
 260
 261        /* Protects ldisc changes: Lock tty not pty */
 262        struct mutex ldisc_mutex;
 263        struct tty_ldisc *ldisc;
 264
 265        struct mutex termios_mutex;
 266        spinlock_t ctrl_lock;
 267        /* Termios values are protected by the termios mutex */
 268        struct ktermios *termios, *termios_locked;
 269        struct termiox *termiox;        /* May be NULL for unsupported */
 270        char name[64];
 271        struct pid *pgrp;               /* Protected by ctrl lock */
 272        struct pid *session;
 273        unsigned long flags;
 274        int count;
 275        struct winsize winsize;         /* termios mutex */
 276        unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
 277        unsigned char low_latency:1, warned:1;
 278        unsigned char ctrl_status;      /* ctrl_lock */
 279        unsigned int receive_room;      /* Bytes free for queue */
 280
 281        struct tty_struct *link;
 282        struct fasync_struct *fasync;
 283        struct tty_bufhead buf;         /* Locked internally */
 284        int alt_speed;          /* For magic substitution of 38400 bps */
 285        wait_queue_head_t write_wait;
 286        wait_queue_head_t read_wait;
 287        struct work_struct hangup_work;
 288        void *disc_data;
 289        void *driver_data;
 290        struct list_head tty_files;
 291
 292#define N_TTY_BUF_SIZE 4096
 293
 294        /*
 295         * The following is data for the N_TTY line discipline.  For
 296         * historical reasons, this is included in the tty structure.
 297         * Mostly locked by the BKL.
 298         */
 299        unsigned int column;
 300        unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
 301        unsigned char closing:1;
 302        unsigned char echo_overrun:1;
 303        unsigned short minimum_to_wake;
 304        unsigned long overrun_time;
 305        int num_overrun;
 306        unsigned long process_char_map[256/(8*sizeof(unsigned long))];
 307        char *read_buf;
 308        int read_head;
 309        int read_tail;
 310        int read_cnt;
 311        unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
 312        unsigned char *echo_buf;
 313        unsigned int echo_pos;
 314        unsigned int echo_cnt;
 315        int canon_data;
 316        unsigned long canon_head;
 317        unsigned int canon_column;
 318        struct mutex atomic_read_lock;
 319        struct mutex atomic_write_lock;
 320        struct mutex output_lock;
 321        struct mutex echo_lock;
 322        unsigned char *write_buf;
 323        int write_cnt;
 324        spinlock_t read_lock;
 325        /* If the tty has a pending do_SAK, queue it here - akpm */
 326        struct work_struct SAK_work;
 327        struct tty_port *port;
 328};
 329
 330/* tty magic number */
 331#define TTY_MAGIC               0x5401
 332
 333/*
 334 * These bits are used in the flags field of the tty structure.
 335 *
 336 * So that interrupts won't be able to mess up the queues,
 337 * copy_to_cooked must be atomic with respect to itself, as must
 338 * tty->write.  Thus, you must use the inline functions set_bit() and
 339 * clear_bit() to make things atomic.
 340 */
 341#define TTY_THROTTLED           0       /* Call unthrottle() at threshold min */
 342#define TTY_IO_ERROR            1       /* Cause an I/O error (may be no ldisc too) */
 343#define TTY_OTHER_CLOSED        2       /* Other side (if any) has closed */
 344#define TTY_EXCLUSIVE           3       /* Exclusive open mode */
 345#define TTY_DEBUG               4       /* Debugging */
 346#define TTY_DO_WRITE_WAKEUP     5       /* Call write_wakeup after queuing new */
 347#define TTY_PUSH                6       /* n_tty private */
 348#define TTY_CLOSING             7       /* ->close() in progress */
 349#define TTY_LDISC               9       /* Line discipline attached */
 350#define TTY_LDISC_CHANGING      10      /* Line discipline changing */
 351#define TTY_LDISC_OPEN          11      /* Line discipline is open */
 352#define TTY_HW_COOK_OUT         14      /* Hardware can do output cooking */
 353#define TTY_HW_COOK_IN          15      /* Hardware can do input cooking */
 354#define TTY_PTY_LOCK            16      /* pty private */
 355#define TTY_NO_WRITE_SPLIT      17      /* Preserve write boundaries to driver */
 356#define TTY_HUPPED              18      /* Post driver->hangup() */
 357#define TTY_FLUSHING            19      /* Flushing to ldisc in progress */
 358#define TTY_FLUSHPENDING        20      /* Queued buffer flush pending */
 359
 360#define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
 361
 362extern void tty_write_flush(struct tty_struct *);
 363
 364extern struct ktermios tty_std_termios;
 365
 366extern void console_init(void);
 367extern int vcs_init(void);
 368
 369extern struct class *tty_class;
 370
 371/**
 372 *      tty_kref_get            -       get a tty reference
 373 *      @tty: tty device
 374 *
 375 *      Return a new reference to a tty object. The caller must hold
 376 *      sufficient locks/counts to ensure that their existing reference cannot
 377 *      go away
 378 */
 379
 380static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 381{
 382        if (tty)
 383                kref_get(&tty->kref);
 384        return tty;
 385}
 386extern void tty_kref_put(struct tty_struct *tty);
 387
 388extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
 389                              const char *routine);
 390extern char *tty_name(struct tty_struct *tty, char *buf);
 391extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
 392extern int tty_check_change(struct tty_struct *tty);
 393extern void stop_tty(struct tty_struct *tty);
 394extern void start_tty(struct tty_struct *tty);
 395extern int tty_register_driver(struct tty_driver *driver);
 396extern int tty_unregister_driver(struct tty_driver *driver);
 397extern struct device *tty_register_device(struct tty_driver *driver,
 398                                          unsigned index, struct device *dev);
 399extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
 400extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
 401                             int buflen);
 402extern void tty_write_message(struct tty_struct *tty, char *msg);
 403extern int tty_put_char(struct tty_struct *tty, unsigned char c);
 404extern int tty_chars_in_buffer(struct tty_struct *tty);
 405extern int tty_write_room(struct tty_struct *tty);
 406extern void tty_driver_flush_buffer(struct tty_struct *tty);
 407extern void tty_throttle(struct tty_struct *tty);
 408extern void tty_unthrottle(struct tty_struct *tty);
 409extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 410extern void tty_shutdown(struct tty_struct *tty);
 411extern void tty_free_termios(struct tty_struct *tty);
 412extern int is_current_pgrp_orphaned(void);
 413extern struct pid *tty_get_pgrp(struct tty_struct *tty);
 414extern int is_ignored(int sig);
 415extern int tty_signal(int sig, struct tty_struct *tty);
 416extern void tty_hangup(struct tty_struct *tty);
 417extern void tty_vhangup(struct tty_struct *tty);
 418extern void tty_vhangup_self(void);
 419extern void tty_unhangup(struct file *filp);
 420extern int tty_hung_up_p(struct file *filp);
 421extern void do_SAK(struct tty_struct *tty);
 422extern void __do_SAK(struct tty_struct *tty);
 423extern void disassociate_ctty(int priv);
 424extern void no_tty(void);
 425extern void tty_flip_buffer_push(struct tty_struct *tty);
 426extern void tty_flush_to_ldisc(struct tty_struct *tty);
 427extern void tty_buffer_free_all(struct tty_struct *tty);
 428extern void tty_buffer_flush(struct tty_struct *tty);
 429extern void tty_buffer_init(struct tty_struct *tty);
 430extern speed_t tty_get_baud_rate(struct tty_struct *tty);
 431extern speed_t tty_termios_baud_rate(struct ktermios *termios);
 432extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
 433extern void tty_termios_encode_baud_rate(struct ktermios *termios,
 434                                                speed_t ibaud, speed_t obaud);
 435extern void tty_encode_baud_rate(struct tty_struct *tty,
 436                                                speed_t ibaud, speed_t obaud);
 437extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 438extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
 439
 440extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
 441extern void tty_ldisc_deref(struct tty_ldisc *);
 442extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
 443extern void tty_ldisc_hangup(struct tty_struct *tty);
 444extern const struct file_operations tty_ldiscs_proc_fops;
 445
 446extern void tty_wakeup(struct tty_struct *tty);
 447extern void tty_ldisc_flush(struct tty_struct *tty);
 448
 449extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 450extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 451                        unsigned int cmd, unsigned long arg);
 452extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 453extern dev_t tty_devnum(struct tty_struct *tty);
 454extern void proc_clear_tty(struct task_struct *p);
 455extern struct tty_struct *get_current_tty(void);
 456extern void tty_default_fops(struct file_operations *fops);
 457extern struct tty_struct *alloc_tty_struct(void);
 458extern void free_tty_struct(struct tty_struct *tty);
 459extern void initialize_tty_struct(struct tty_struct *tty,
 460                struct tty_driver *driver, int idx);
 461extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
 462                                                                int first_ok);
 463extern int tty_release(struct inode *inode, struct file *filp);
 464extern int tty_init_termios(struct tty_struct *tty);
 465
 466extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
 467extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
 468
 469extern struct mutex tty_mutex;
 470
 471extern void tty_write_unlock(struct tty_struct *tty);
 472extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 473#define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
 474
 475extern void tty_port_init(struct tty_port *port);
 476extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 477extern void tty_port_free_xmit_buf(struct tty_port *port);
 478extern void tty_port_put(struct tty_port *port);
 479
 480static inline struct tty_port *tty_port_get(struct tty_port *port)
 481{
 482        if (port)
 483                kref_get(&port->kref);
 484        return port;
 485}
 486
 487extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 488extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 489extern int tty_port_carrier_raised(struct tty_port *port);
 490extern void tty_port_raise_dtr_rts(struct tty_port *port);
 491extern void tty_port_lower_dtr_rts(struct tty_port *port);
 492extern void tty_port_hangup(struct tty_port *port);
 493extern int tty_port_block_til_ready(struct tty_port *port,
 494                                struct tty_struct *tty, struct file *filp);
 495extern int tty_port_close_start(struct tty_port *port,
 496                                struct tty_struct *tty, struct file *filp);
 497extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
 498extern void tty_port_close(struct tty_port *port,
 499                                struct tty_struct *tty, struct file *filp);
 500extern int tty_port_open(struct tty_port *port,
 501                                struct tty_struct *tty, struct file *filp);
 502static inline int tty_port_users(struct tty_port *port)
 503{
 504        return port->count + port->blocked_open;
 505}
 506
 507extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
 508extern int tty_unregister_ldisc(int disc);
 509extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
 510extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
 511extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
 512extern void tty_ldisc_init(struct tty_struct *tty);
 513extern void tty_ldisc_begin(void);
 514/* This last one is just for the tty layer internals and shouldn't be used elsewhere */
 515extern void tty_ldisc_enable(struct tty_struct *tty);
 516
 517
 518/* n_tty.c */
 519extern struct tty_ldisc_ops tty_ldisc_N_TTY;
 520extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 521
 522/* tty_audit.c */
 523#ifdef CONFIG_AUDIT
 524extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
 525                               size_t size);
 526extern void tty_audit_exit(void);
 527extern void tty_audit_fork(struct signal_struct *sig);
 528extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
 529extern void tty_audit_push(struct tty_struct *tty);
 530extern void tty_audit_push_task(struct task_struct *tsk,
 531                                        uid_t loginuid, u32 sessionid);
 532#else
 533static inline void tty_audit_add_data(struct tty_struct *tty,
 534                                      unsigned char *data, size_t size)
 535{
 536}
 537static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
 538{
 539}
 540static inline void tty_audit_exit(void)
 541{
 542}
 543static inline void tty_audit_fork(struct signal_struct *sig)
 544{
 545}
 546static inline void tty_audit_push(struct tty_struct *tty)
 547{
 548}
 549static inline void tty_audit_push_task(struct task_struct *tsk,
 550                                        uid_t loginuid, u32 sessionid)
 551{
 552}
 553#endif
 554
 555/* tty_ioctl.c */
 556extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 557                       unsigned int cmd, unsigned long arg);
 558
 559/* serial.c */
 560
 561extern void serial_console_init(void);
 562
 563/* pcxx.c */
 564
 565extern int pcxe_open(struct tty_struct *tty, struct file *filp);
 566
 567/* vt.c */
 568
 569extern int vt_ioctl(struct tty_struct *tty, struct file *file,
 570                    unsigned int cmd, unsigned long arg);
 571
 572extern long vt_compat_ioctl(struct tty_struct *tty, struct file * file,
 573                     unsigned int cmd, unsigned long arg);
 574
 575#endif /* __KERNEL__ */
 576#endif
 577