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 #define NR_LDISCS               30
   9
  10 /* line disciplines */
  11 #define N_TTY           0
  12 #define N_SLIP          1
  13 #define N_MOUSE         2
  14 #define N_PPP           3
  15 #define N_STRIP         4
  16 #define N_AX25          5
  17 #define N_X25           6       /* X.25 async */
  18 #define N_6PACK         7
  19 #define N_MASC          8       /* Reserved for Mobitex module <kaz@cafe.net> */
  20 #define N_R3964         9       /* Reserved for Simatic R3964 module */
  21 #define N_PROFIBUS_FDL  10      /* Reserved for Profibus */
  22 #define N_IRDA          11      /* Linux IrDa - http://irda.sourceforge.net/ */
  23 #define N_SMSBLOCK      12      /* SMS block mode - for talking to GSM data */
  24                                 /* cards about SMS messages */
  25 #define N_HDLC          13      /* synchronous HDLC */
  26 #define N_SYNC_PPP      14      /* synchronous PPP */
  27 #define N_HCI           15      /* Bluetooth HCI UART */
  28 #define N_GIGASET_M101  16      /* Siemens Gigaset M101 serial DECT adapter */
  29 #define N_SLCAN         17      /* Serial / USB serial CAN Adaptors */
  30 #define N_PPS           18      /* Pulse per Second */
  31 #define N_V253          19      /* Codec control over voice modem */
  32 #define N_CAIF          20      /* CAIF protocol for talking to modems */
  33 #define N_GSM0710       21      /* GSM 0710 Mux */
  34 #define N_TI_WL         22      /* for TI's WL BT, FM, GPS combo chips */
  35 #define N_TRACESINK     23      /* Trace data routing for MIPI P1149.7 */
  36 #define N_TRACEROUTER   24      /* Trace data routing for MIPI P1149.7 */
  37
  38 #ifdef __KERNEL__
  39 #include <linux/fs.h>
  40 #include <linux/major.h>
  41 #include <linux/termios.h>
  42 #include <linux/workqueue.h>
  43 #include <linux/tty_driver.h>
  44 #include <linux/tty_ldisc.h>
  45 #include <linux/mutex.h>
  46
  47 #include <asm/system.h>
  48
  49
  50 /*
  51  * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
  52  * hardcoded at present.)
  53  */
  54 #define NR_UNIX98_PTY_DEFAULT   4096      /* Default maximum for Unix98 ptys */
  55 #define NR_UNIX98_PTY_MAX       (1 << MINORBITS) /* Absolute limit */
  56
  57 /*
  58  * This character is the same as _POSIX_VDISABLE: it cannot be used as
  59  * a c_cc[] character, but indicates that a particular special character
  60  * isn't in use (eg VINTR has no character etc)
  61  */
  62 #define __DISABLED_CHAR '\0'
  63
  64 struct tty_buffer {
  65         struct tty_buffer *next;
  66         char *char_buf_ptr;
  67         unsigned char *flag_buf_ptr;
  68         int used;
  69         int size;
  70         int commit;
  71         int read;
  72         /* Data points here */
  73         unsigned long data[0];
  74 };
  75
  76 /*
  77  * We default to dicing tty buffer allocations to this many characters
  78  * in order to avoid multiple page allocations. We know the size of
  79  * tty_buffer itself but it must also be taken into account that the
  80  * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
  81  * logic this must match
  82  */
  83
  84 #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
  85
  86
  87 struct tty_bufhead {
  88         struct work_struct work;
  89         spinlock_t lock;
  90         struct tty_buffer *head;        /* Queue head */
  91         struct tty_buffer *tail;        /* Active buffer */
  92         struct tty_buffer *free;        /* Free queue head */
  93         int memory_used;                /* Buffer space used excluding
  94                                                                 free queue */
  95 };
  96 /*
  97  * When a break, frame error, or parity error happens, these codes are
  98  * stuffed into the flags buffer.
  99  */
 100 #define TTY_NORMAL      0
 101 #define TTY_BREAK       1
 102 #define TTY_FRAME       2
 103 #define TTY_PARITY      3
 104 #define TTY_OVERRUN     4
 105
 106 #define INTR_CHAR(tty) ((tty)->termios->c_cc[VINTR])
 107 #define QUIT_CHAR(tty) ((tty)->termios->c_cc[VQUIT])
 108 #define ERASE_CHAR(tty) ((tty)->termios->c_cc[VERASE])
 109 #define KILL_CHAR(tty) ((tty)->termios->c_cc[VKILL])
 110 #define EOF_CHAR(tty) ((tty)->termios->c_cc[VEOF])
 111 #define TIME_CHAR(tty) ((tty)->termios->c_cc[VTIME])
 112 #define MIN_CHAR(tty) ((tty)->termios->c_cc[VMIN])
 113 #define SWTC_CHAR(tty) ((tty)->termios->c_cc[VSWTC])
 114 #define START_CHAR(tty) ((tty)->termios->c_cc[VSTART])
 115 #define STOP_CHAR(tty) ((tty)->termios->c_cc[VSTOP])
 116 #define SUSP_CHAR(tty) ((tty)->termios->c_cc[VSUSP])
 117 #define EOL_CHAR(tty) ((tty)->termios->c_cc[VEOL])
 118 #define REPRINT_CHAR(tty) ((tty)->termios->c_cc[VREPRINT])
 119 #define DISCARD_CHAR(tty) ((tty)->termios->c_cc[VDISCARD])
 120 #define WERASE_CHAR(tty) ((tty)->termios->c_cc[VWERASE])
 121 #define LNEXT_CHAR(tty) ((tty)->termios->c_cc[VLNEXT])
 122 #define EOL2_CHAR(tty) ((tty)->termios->c_cc[VEOL2])
 123
 124 #define _I_FLAG(tty, f) ((tty)->termios->c_iflag & (f))
 125 #define _O_FLAG(tty, f) ((tty)->termios->c_oflag & (f))
 126 #define _C_FLAG(tty, f) ((tty)->termios->c_cflag & (f))
 127 #define _L_FLAG(tty, f) ((tty)->termios->c_lflag & (f))
 128
 129 #define I_IGNBRK(tty)   _I_FLAG((tty), IGNBRK)
 130 #define I_BRKINT(tty)   _I_FLAG((tty), BRKINT)
 131 #define I_IGNPAR(tty)   _I_FLAG((tty), IGNPAR)
 132 #define I_PARMRK(tty)   _I_FLAG((tty), PARMRK)
 133 #define I_INPCK(tty)    _I_FLAG((tty), INPCK)
 134 #define I_ISTRIP(tty)   _I_FLAG((tty), ISTRIP)
 135 #define I_INLCR(tty)    _I_FLAG((tty), INLCR)
 136 #define I_IGNCR(tty)    _I_FLAG((tty), IGNCR)
 137 #define I_ICRNL(tty)    _I_FLAG((tty), ICRNL)
 138 #define I_IUCLC(tty)    _I_FLAG((tty), IUCLC)
 139 #define I_IXON(tty)     _I_FLAG((tty), IXON)
 140 #define I_IXANY(tty)    _I_FLAG((tty), IXANY)
 141 #define I_IXOFF(tty)    _I_FLAG((tty), IXOFF)
 142 #define I_IMAXBEL(tty)  _I_FLAG((tty), IMAXBEL)
 143 #define I_IUTF8(tty)    _I_FLAG((tty), IUTF8)
 144
 145 #define O_OPOST(tty)    _O_FLAG((tty), OPOST)
 146 #define O_OLCUC(tty)    _O_FLAG((tty), OLCUC)
 147 #define O_ONLCR(tty)    _O_FLAG((tty), ONLCR)
 148 #define O_OCRNL(tty)    _O_FLAG((tty), OCRNL)
 149 #define O_ONOCR(tty)    _O_FLAG((tty), ONOCR)
 150 #define O_ONLRET(tty)   _O_FLAG((tty), ONLRET)
 151 #define O_OFILL(tty)    _O_FLAG((tty), OFILL)
 152 #define O_OFDEL(tty)    _O_FLAG((tty), OFDEL)
 153 #define O_NLDLY(tty)    _O_FLAG((tty), NLDLY)
 154 #define O_CRDLY(tty)    _O_FLAG((tty), CRDLY)
 155 #define O_TABDLY(tty)   _O_FLAG((tty), TABDLY)
 156 #define O_BSDLY(tty)    _O_FLAG((tty), BSDLY)
 157 #define O_VTDLY(tty)    _O_FLAG((tty), VTDLY)
 158 #define O_FFDLY(tty)    _O_FLAG((tty), FFDLY)
 159
 160 #define C_BAUD(tty)     _C_FLAG((tty), CBAUD)
 161 #define C_CSIZE(tty)    _C_FLAG((tty), CSIZE)
 162 #define C_CSTOPB(tty)   _C_FLAG((tty), CSTOPB)
 163 #define C_CREAD(tty)    _C_FLAG((tty), CREAD)
 164 #define C_PARENB(tty)   _C_FLAG((tty), PARENB)
 165 #define C_PARODD(tty)   _C_FLAG((tty), PARODD)
 166 #define C_HUPCL(tty)    _C_FLAG((tty), HUPCL)
 167 #define C_CLOCAL(tty)   _C_FLAG((tty), CLOCAL)
 168 #define C_CIBAUD(tty)   _C_FLAG((tty), CIBAUD)
 169 #define C_CRTSCTS(tty)  _C_FLAG((tty), CRTSCTS)
 170
 171 #define L_ISIG(tty)     _L_FLAG((tty), ISIG)
 172 #define L_ICANON(tty)   _L_FLAG((tty), ICANON)
 173 #define L_XCASE(tty)    _L_FLAG((tty), XCASE)
 174 #define L_ECHO(tty)     _L_FLAG((tty), ECHO)
 175 #define L_ECHOE(tty)    _L_FLAG((tty), ECHOE)
 176 #define L_ECHOK(tty)    _L_FLAG((tty), ECHOK)
 177 #define L_ECHONL(tty)   _L_FLAG((tty), ECHONL)
 178 #define L_NOFLSH(tty)   _L_FLAG((tty), NOFLSH)
 179 #define L_TOSTOP(tty)   _L_FLAG((tty), TOSTOP)
 180 #define L_ECHOCTL(tty)  _L_FLAG((tty), ECHOCTL)
 181 #define L_ECHOPRT(tty)  _L_FLAG((tty), ECHOPRT)
 182 #define L_ECHOKE(tty)   _L_FLAG((tty), ECHOKE)
 183 #define L_FLUSHO(tty)   _L_FLAG((tty), FLUSHO)
 184 #define L_PENDIN(tty)   _L_FLAG((tty), PENDIN)
 185 #define L_IEXTEN(tty)   _L_FLAG((tty), IEXTEN)
 186 #define L_EXTPROC(tty)  _L_FLAG((tty), EXTPROC)
 187
 188 struct device;
 189 struct signal_struct;
 190
 191 /*
 192  * Port level information. Each device keeps its own port level information
 193  * so provide a common structure for those ports wanting to use common support
 194  * routines.
 195  *
 196  * The tty port has a different lifetime to the tty so must be kept apart.
 197  * In addition be careful as tty -> port mappings are valid for the life
 198  * of the tty object but in many cases port -> tty mappings are valid only
 199  * until a hangup so don't use the wrong path.
 200  */
 201
 202 struct tty_port;
 203
 204 struct tty_port_operations {
 205         /* Return 1 if the carrier is raised */
 206         int (*carrier_raised)(struct tty_port *port);
 207         /* Control the DTR line */
 208         void (*dtr_rts)(struct tty_port *port, int raise);
 209         /* Called when the last close completes or a hangup finishes
 210            IFF the port was initialized. Do not use to free resources. Called
 211            under the port mutex to serialize against activate/shutdowns */
 212         void (*shutdown)(struct tty_port *port);
 213         void (*drop)(struct tty_port *port);
 214         /* Called under the port mutex from tty_port_open, serialized using
 215            the port mutex */
 216         /* FIXME: long term getting the tty argument *out* of this would be
 217            good for consoles */
 218         int (*activate)(struct tty_port *port, struct tty_struct *tty);
 219         /* Called on the final put of a port */
 220         void (*destruct)(struct tty_port *port);
 221 };
 222
 223 struct tty_port {
 224         struct tty_struct       *tty;           /* Back pointer */
 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       close_wait;     /* Close waiters */
 231         wait_queue_head_t       delta_msr_wait; /* Modem status change */
 232         unsigned long           flags;          /* TTY flags ASY_*/
 233         unsigned char           console:1;      /* port is a console */
 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
 257 struct tty_operations;
 258
 259 struct 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 mutex ldisc_mutex;
 269         struct tty_ldisc *ldisc;
 270
 271         struct mutex termios_mutex;
 272         spinlock_t ctrl_lock;
 273         /* Termios values are protected by the termios mutex */
 274         struct ktermios *termios, *termios_locked;
 275         struct termiox *termiox;        /* May be NULL for unsupported */
 276         char name[64];
 277         struct pid *pgrp;               /* Protected by ctrl lock */
 278         struct pid *session;
 279         unsigned long flags;
 280         int count;
 281         struct winsize winsize;         /* termios mutex */
 282         unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
 283         unsigned char low_latency:1, warned:1;
 284         unsigned char ctrl_status;      /* ctrl_lock */
 285         unsigned int receive_room;      /* Bytes free for queue */
 286
 287         struct tty_struct *link;
 288         struct fasync_struct *fasync;
 289         struct tty_bufhead buf;         /* Locked internally */
 290         int alt_speed;          /* For magic substitution of 38400 bps */
 291         wait_queue_head_t write_wait;
 292         wait_queue_head_t read_wait;
 293         struct work_struct hangup_work;
 294         void *disc_data;
 295         void *driver_data;
 296         struct list_head tty_files;
 297
 298 #define N_TTY_BUF_SIZE 4096
 299
 300         /*
 301          * The following is data for the N_TTY line discipline.  For
 302          * historical reasons, this is included in the tty structure.
 303          * Mostly locked by the BKL.
 304          */
 305         unsigned int column;
 306         unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
 307         unsigned char closing:1;
 308         unsigned char echo_overrun:1;
 309         unsigned short minimum_to_wake;
 310         unsigned long overrun_time;
 311         int num_overrun;
 312         unsigned long process_char_map[256/(8*sizeof(unsigned long))];
 313         char *read_buf;
 314         int read_head;
 315         int read_tail;
 316         int read_cnt;
 317         unsigned long read_flags[N_TTY_BUF_SIZE/(8*sizeof(unsigned long))];
 318         unsigned char *echo_buf;
 319         unsigned int echo_pos;
 320         unsigned int echo_cnt;
 321         int canon_data;
 322         unsigned long canon_head;
 323         unsigned int canon_column;
 324         struct mutex atomic_read_lock;
 325         struct mutex atomic_write_lock;
 326         struct mutex output_lock;
 327         struct mutex echo_lock;
 328         unsigned char *write_buf;
 329         int write_cnt;
 330         spinlock_t read_lock;
 331         /* If the tty has a pending do_SAK, queue it here - akpm */
 332         struct work_struct SAK_work;
 333         struct tty_port *port;
 334 };
 335
 336 /* Each of a tty's open files has private_data pointing to tty_file_private */
 337 struct tty_file_private {
 338         struct tty_struct *tty;
 339         struct file *file;
 340         struct list_head list;
 341 };
 342
 343 /* tty magic number */
 344 #define TTY_MAGIC               0x5401
 345
 346 /*
 347  * These bits are used in the flags field of the tty structure.
 348  *
 349  * So that interrupts won't be able to mess up the queues,
 350  * copy_to_cooked must be atomic with respect to itself, as must
 351  * tty->write.  Thus, you must use the inline functions set_bit() and
 352  * clear_bit() to make things atomic.
 353  */
 354 #define TTY_THROTTLED           0       /* Call unthrottle() at threshold min */
 355 #define TTY_IO_ERROR            1       /* Cause an I/O error (may be no ldisc too) */
 356 #define TTY_OTHER_CLOSED        2       /* Other side (if any) has closed */
 357 #define TTY_EXCLUSIVE           3       /* Exclusive open mode */
 358 #define TTY_DEBUG               4       /* Debugging */
 359 #define TTY_DO_WRITE_WAKEUP     5       /* Call write_wakeup after queuing new */
 360 #define TTY_PUSH                6       /* n_tty private */
 361 #define TTY_CLOSING             7       /* ->close() in progress */
 362 #define TTY_LDISC               9       /* Line discipline attached */
 363 #define TTY_LDISC_CHANGING      10      /* Line discipline changing */
 364 #define TTY_LDISC_OPEN          11      /* Line discipline is open */
 365 #define TTY_HW_COOK_OUT         14      /* Hardware can do output cooking */
 366 #define TTY_HW_COOK_IN          15      /* Hardware can do input cooking */
 367 #define TTY_PTY_LOCK            16      /* pty private */
 368 #define TTY_NO_WRITE_SPLIT      17      /* Preserve write boundaries to driver */
 369 #define TTY_HUPPED              18      /* Post driver->hangup() */
 370 #define TTY_FLUSHING            19      /* Flushing to ldisc in progress */
 371 #define TTY_FLUSHPENDING        20      /* Queued buffer flush pending */
 372 #define TTY_HUPPING             21      /* ->hangup() in progress */
 373
 374 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
 375
 376 extern void tty_write_flush(struct tty_struct *);
 377
 378 extern struct ktermios tty_std_termios;
 379
 380 extern void console_init(void);
 381 extern int vcs_init(void);
 382
 383 extern struct class *tty_class;
 384
 385 /**
 386  *      tty_kref_get            -       get a tty reference
 387  *      @tty: tty device
 388  *
 389  *      Return a new reference to a tty object. The caller must hold
 390  *      sufficient locks/counts to ensure that their existing reference cannot
 391  *      go away
 392  */
 393
 394 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 395 {
 396         if (tty)
 397                 kref_get(&tty->kref);
 398         return tty;
 399 }
 400 extern void tty_kref_put(struct tty_struct *tty);
 401
 402 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
 403                               const char *routine);
 404 extern char *tty_name(struct tty_struct *tty, char *buf);
 405 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
 406 extern int tty_check_change(struct tty_struct *tty);
 407 extern void stop_tty(struct tty_struct *tty);
 408 extern void start_tty(struct tty_struct *tty);
 409 extern int tty_register_driver(struct tty_driver *driver);
 410 extern int tty_unregister_driver(struct tty_driver *driver);
 411 extern struct device *tty_register_device(struct tty_driver *driver,
 412                                           unsigned index, struct device *dev);
 413 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
 414 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
 415                              int buflen);
 416 extern void tty_write_message(struct tty_struct *tty, char *msg);
 417 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
 418 extern int tty_chars_in_buffer(struct tty_struct *tty);
 419 extern int tty_write_room(struct tty_struct *tty);
 420 extern void tty_driver_flush_buffer(struct tty_struct *tty);
 421 extern void tty_throttle(struct tty_struct *tty);
 422 extern void tty_unthrottle(struct tty_struct *tty);
 423 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 424 extern void tty_driver_remove_tty(struct tty_driver *driver,
 425                                   struct tty_struct *tty);
 426 extern void tty_shutdown(struct tty_struct *tty);
 427 extern void tty_free_termios(struct tty_struct *tty);
 428 extern int is_current_pgrp_orphaned(void);
 429 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
 430 extern int is_ignored(int sig);
 431 extern int tty_signal(int sig, struct tty_struct *tty);
 432 extern void tty_hangup(struct tty_struct *tty);
 433 extern void tty_vhangup(struct tty_struct *tty);
 434 extern void tty_vhangup_locked(struct tty_struct *tty);
 435 extern void tty_vhangup_self(void);
 436 extern void tty_unhangup(struct file *filp);
 437 extern int tty_hung_up_p(struct file *filp);
 438 extern void do_SAK(struct tty_struct *tty);
 439 extern void __do_SAK(struct tty_struct *tty);
 440 extern void disassociate_ctty(int priv);
 441 extern void no_tty(void);
 442 extern void tty_flip_buffer_push(struct tty_struct *tty);
 443 extern void tty_flush_to_ldisc(struct tty_struct *tty);
 444 extern void tty_buffer_free_all(struct tty_struct *tty);
 445 extern void tty_buffer_flush(struct tty_struct *tty);
 446 extern void tty_buffer_init(struct tty_struct *tty);
 447 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
 448 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
 449 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
 450 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
 451                                                 speed_t ibaud, speed_t obaud);
 452 extern void tty_encode_baud_rate(struct tty_struct *tty,
 453                                                 speed_t ibaud, speed_t obaud);
 454 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 455 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
 456 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 457
 458 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
 459 extern void tty_ldisc_deref(struct tty_ldisc *);
 460 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
 461 extern void tty_ldisc_hangup(struct tty_struct *tty);
 462 extern const struct file_operations tty_ldiscs_proc_fops;
 463
 464 extern void tty_wakeup(struct tty_struct *tty);
 465 extern void tty_ldisc_flush(struct tty_struct *tty);
 466
 467 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 468 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 469                         unsigned int cmd, unsigned long arg);
 470 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 471 extern dev_t tty_devnum(struct tty_struct *tty);
 472 extern void proc_clear_tty(struct task_struct *p);
 473 extern struct tty_struct *get_current_tty(void);
 474 extern void tty_default_fops(struct file_operations *fops);
 475 extern struct tty_struct *alloc_tty_struct(void);
 476 extern int tty_alloc_file(struct file *file);
 477 extern void tty_add_file(struct tty_struct *tty, struct file *file);
 478 extern void tty_free_file(struct file *file);
 479 extern void free_tty_struct(struct tty_struct *tty);
 480 extern void initialize_tty_struct(struct tty_struct *tty,
 481                 struct tty_driver *driver, int idx);
 482 extern void deinitialize_tty_struct(struct tty_struct *tty);
 483 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
 484 extern int tty_release(struct inode *inode, struct file *filp);
 485 extern int tty_init_termios(struct tty_struct *tty);
 486
 487 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
 488 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
 489
 490 extern struct mutex tty_mutex;
 491 extern spinlock_t tty_files_lock;
 492
 493 extern void tty_write_unlock(struct tty_struct *tty);
 494 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 495 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
 496
 497 extern void tty_port_init(struct tty_port *port);
 498 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 499 extern void tty_port_free_xmit_buf(struct tty_port *port);
 500 extern void tty_port_put(struct tty_port *port);
 501
 502 static inline struct tty_port *tty_port_get(struct tty_port *port)
 503 {
 504         if (port)
 505                 kref_get(&port->kref);
 506         return port;
 507 }
 508
 509 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 510 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 511 extern int tty_port_carrier_raised(struct tty_port *port);
 512 extern void tty_port_raise_dtr_rts(struct tty_port *port);
 513 extern void tty_port_lower_dtr_rts(struct tty_port *port);
 514 extern void tty_port_hangup(struct tty_port *port);
 515 extern int tty_port_block_til_ready(struct tty_port *port,
 516                                 struct tty_struct *tty, struct file *filp);
 517 extern int tty_port_close_start(struct tty_port *port,
 518                                 struct tty_struct *tty, struct file *filp);
 519 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
 520 extern void tty_port_close(struct tty_port *port,
 521                                 struct tty_struct *tty, struct file *filp);
 522 extern int tty_port_open(struct tty_port *port,
 523                                 struct tty_struct *tty, struct file *filp);
 524 static inline int tty_port_users(struct tty_port *port)
 525 {
 526         return port->count + port->blocked_open;
 527 }
 528
 529 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
 530 extern int tty_unregister_ldisc(int disc);
 531 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
 532 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
 533 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
 534 extern void tty_ldisc_init(struct tty_struct *tty);
 535 extern void tty_ldisc_deinit(struct tty_struct *tty);
 536 extern void tty_ldisc_begin(void);
 537 /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
 538 extern void tty_ldisc_enable(struct tty_struct *tty);
 539
 540
 541 /* n_tty.c */
 542 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
 543 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 544
 545 /* tty_audit.c */
 546 #ifdef CONFIG_AUDIT
 547 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
 548                                size_t size);
 549 extern void tty_audit_exit(void);
 550 extern void tty_audit_fork(struct signal_struct *sig);
 551 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
 552 extern void tty_audit_push(struct tty_struct *tty);
 553 extern int tty_audit_push_task(struct task_struct *tsk,
 554                                uid_t loginuid, u32 sessionid);
 555 #else
 556 static inline void tty_audit_add_data(struct tty_struct *tty,
 557                                       unsigned char *data, size_t size)
 558 {
 559 }
 560 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
 561 {
 562 }
 563 static inline void tty_audit_exit(void)
 564 {
 565 }
 566 static inline void tty_audit_fork(struct signal_struct *sig)
 567 {
 568 }
 569 static inline void tty_audit_push(struct tty_struct *tty)
 570 {
 571 }
 572 static inline int tty_audit_push_task(struct task_struct *tsk,
 573                                       uid_t loginuid, u32 sessionid)
 574 {
 575         return 0;
 576 }
 577 #endif
 578
 579 /* tty_io.c */
 580 extern int __init tty_init(void);
 581
 582 /* tty_ioctl.c */
 583 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 584                        unsigned int cmd, unsigned long arg);
 585 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
 586                        unsigned int cmd, unsigned long arg);
 587
 588 /* serial.c */
 589
 590 extern void serial_console_init(void);
 591
 592 /* pcxx.c */
 593
 594 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
 595
 596 /* vt.c */
 597
 598 extern int vt_ioctl(struct tty_struct *tty,
 599                     unsigned int cmd, unsigned long arg);
 600
 601 extern long vt_compat_ioctl(struct tty_struct *tty,
 602                      unsigned int cmd, unsigned long arg);
 603
 604 /* tty_mutex.c */
 605 /* functions for preparation of BKL removal */
 606 extern void __lockfunc tty_lock(void) __acquires(tty_lock);
 607 extern void __lockfunc tty_unlock(void) __releases(tty_lock);
 608
 609 /*
 610  * this shall be called only from where BTM is held (like close)
 611  *
 612  * We need this to ensure nobody waits for us to finish while we are waiting.
 613  * Without this we were encountering system stalls.
 614  *
 615  * This should be indeed removed with BTM removal later.
 616  *
 617  * Locking: BTM required. Nobody is allowed to hold port->mutex.
 618  */
 619 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
 620                 long timeout)
 621 {
 622         tty_unlock(); /* tty->ops->close holds the BTM, drop it while waiting */
 623         tty_wait_until_sent(tty, timeout);
 624         tty_lock();
 625 }
 626
 627 /*
 628  * wait_event_interruptible_tty -- wait for a condition with the tty lock held
 629  *
 630  * The condition we are waiting for might take a long time to
 631  * become true, or might depend on another thread taking the
 632  * BTM. In either case, we need to drop the BTM to guarantee
 633  * forward progress. This is a leftover from the conversion
 634  * from the BKL and should eventually get removed as the BTM
 635  * falls out of use.
 636  *
 637  * Do not use in new code.
 638  */
 639 #define wait_event_interruptible_tty(wq, condition)                     \
 640 ({                                                                      \
 641         int __ret = 0;                                                  \
 642         if (!(condition)) {                                             \
 643                 __wait_event_interruptible_tty(wq, condition, __ret);   \
 644         }                                                               \
 645         __ret;                                                          \
 646 })
 647
 648 #define __wait_event_interruptible_tty(wq, condition, ret)              \
 649 do {                                                                    \
 650         DEFINE_WAIT(__wait);                                            \
 651                                                                         \
 652         for (;;) {                                                      \
 653                 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);      \
 654                 if (condition)                                          \
 655                         break;                                          \
 656                 if (!signal_pending(current)) {                         \
 657                         tty_unlock();                                   \
 658                         schedule();                                     \
 659                         tty_lock();                                     \
 660                         continue;                                       \
 661                 }                                                       \
 662                 ret = -ERESTARTSYS;                                     \
 663                 break;                                                  \
 664         }                                                               \
 665         finish_wait(&wq, &__wait);                                      \
 666 } while (0)
 667
 668
 669 #endif /* __KERNEL__ */
 670 #endif