include/linux/tty.h

   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
  14
  15
  16 /*
  17  * (Note: the *_driver.minor_start values 1, 64, 128, 192 are
  18  * hardcoded at present.)
  19  */
  20 #define NR_UNIX98_PTY_DEFAULT   4096      /* Default maximum for Unix98 ptys */
  21 #define NR_UNIX98_PTY_RESERVE   1024      /* Default reserve for main devpts */
  22 #define NR_UNIX98_PTY_MAX       (1 << MINORBITS) /* Absolute limit */
  23
  24 /*
  25  * This character is the same as _POSIX_VDISABLE: it cannot be used as
  26  * a c_cc[] character, but indicates that a particular special character
  27  * isn't in use (eg VINTR has no character etc)
  28  */
  29 #define __DISABLED_CHAR '\0'
  30
  31 struct tty_buffer {
  32         struct tty_buffer *next;
  33         char *char_buf_ptr;
  34         unsigned char *flag_buf_ptr;
  35         int used;
  36         int size;
  37         int commit;
  38         int read;
  39         /* Data points here */
  40         unsigned long data[0];
  41 };
  42
  43 /*
  44  * We default to dicing tty buffer allocations to this many characters
  45  * in order to avoid multiple page allocations. We know the size of
  46  * tty_buffer itself but it must also be taken into account that the
  47  * the buffer is 256 byte aligned. See tty_buffer_find for the allocation
  48  * logic this must match
  49  */
  50
  51 #define TTY_BUFFER_PAGE (((PAGE_SIZE - sizeof(struct tty_buffer)) / 2) & ~0xFF)
  52
  53
  54 struct tty_bufhead {
  55         struct work_struct work;
  56         spinlock_t lock;
  57         struct tty_buffer *head;        /* Queue head */
  58         struct tty_buffer *tail;        /* Active buffer */
  59         struct tty_buffer *free;        /* Free queue head */
  60         int memory_used;                /* Buffer space used excluding
  61                                                                 free queue */
  62 };
  63 /*
  64  * When a break, frame error, or parity error happens, these codes are
  65  * stuffed into the flags buffer.
  66  */
  67 #define TTY_NORMAL      0
  68 #define TTY_BREAK       1
  69 #define TTY_FRAME       2
  70 #define TTY_PARITY      3
  71 #define TTY_OVERRUN     4
  72
  73 #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR])
  74 #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT])
  75 #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE])
  76 #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL])
  77 #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF])
  78 #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME])
  79 #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN])
  80 #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC])
  81 #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART])
  82 #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP])
  83 #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP])
  84 #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL])
  85 #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT])
  86 #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD])
  87 #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE])
  88 #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT])
  89 #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2])
  90
  91 #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f))
  92 #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f))
  93 #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f))
  94 #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f))
  95
  96 #define I_IGNBRK(tty)   _I_FLAG((tty), IGNBRK)
  97 #define I_BRKINT(tty)   _I_FLAG((tty), BRKINT)
  98 #define I_IGNPAR(tty)   _I_FLAG((tty), IGNPAR)
  99 #define I_PARMRK(tty)   _I_FLAG((tty), PARMRK)
 100 #define I_INPCK(tty)    _I_FLAG((tty), INPCK)
 101 #define I_ISTRIP(tty)   _I_FLAG((tty), ISTRIP)
 102 #define I_INLCR(tty)    _I_FLAG((tty), INLCR)
 103 #define I_IGNCR(tty)    _I_FLAG((tty), IGNCR)
 104 #define I_ICRNL(tty)    _I_FLAG((tty), ICRNL)
 105 #define I_IUCLC(tty)    _I_FLAG((tty), IUCLC)
 106 #define I_IXON(tty)     _I_FLAG((tty), IXON)
 107 #define I_IXANY(tty)    _I_FLAG((tty), IXANY)
 108 #define I_IXOFF(tty)    _I_FLAG((tty), IXOFF)
 109 #define I_IMAXBEL(tty)  _I_FLAG((tty), IMAXBEL)
 110 #define I_IUTF8(tty)    _I_FLAG((tty), IUTF8)
 111
 112 #define O_OPOST(tty)    _O_FLAG((tty), OPOST)
 113 #define O_OLCUC(tty)    _O_FLAG((tty), OLCUC)
 114 #define O_ONLCR(tty)    _O_FLAG((tty), ONLCR)
 115 #define O_OCRNL(tty)    _O_FLAG((tty), OCRNL)
 116 #define O_ONOCR(tty)    _O_FLAG((tty), ONOCR)
 117 #define O_ONLRET(tty)   _O_FLAG((tty), ONLRET)
 118 #define O_OFILL(tty)    _O_FLAG((tty), OFILL)
 119 #define O_OFDEL(tty)    _O_FLAG((tty), OFDEL)
 120 #define O_NLDLY(tty)    _O_FLAG((tty), NLDLY)
 121 #define O_CRDLY(tty)    _O_FLAG((tty), CRDLY)
 122 #define O_TABDLY(tty)   _O_FLAG((tty), TABDLY)
 123 #define O_BSDLY(tty)    _O_FLAG((tty), BSDLY)
 124 #define O_VTDLY(tty)    _O_FLAG((tty), VTDLY)
 125 #define O_FFDLY(tty)    _O_FLAG((tty), FFDLY)
 126
 127 #define C_BAUD(tty)     _C_FLAG((tty), CBAUD)
 128 #define C_CSIZE(tty)    _C_FLAG((tty), CSIZE)
 129 #define C_CSTOPB(tty)   _C_FLAG((tty), CSTOPB)
 130 #define C_CREAD(tty)    _C_FLAG((tty), CREAD)
 131 #define C_PARENB(tty)   _C_FLAG((tty), PARENB)
 132 #define C_PARODD(tty)   _C_FLAG((tty), PARODD)
 133 #define C_HUPCL(tty)    _C_FLAG((tty), HUPCL)
 134 #define C_CLOCAL(tty)   _C_FLAG((tty), CLOCAL)
 135 #define C_CIBAUD(tty)   _C_FLAG((tty), CIBAUD)
 136 #define C_CRTSCTS(tty)  _C_FLAG((tty), CRTSCTS)
 137
 138 #define L_ISIG(tty)     _L_FLAG((tty), ISIG)
 139 #define L_ICANON(tty)   _L_FLAG((tty), ICANON)
 140 #define L_XCASE(tty)    _L_FLAG((tty), XCASE)
 141 #define L_ECHO(tty)     _L_FLAG((tty), ECHO)
 142 #define L_ECHOE(tty)    _L_FLAG((tty), ECHOE)
 143 #define L_ECHOK(tty)    _L_FLAG((tty), ECHOK)
 144 #define L_ECHONL(tty)   _L_FLAG((tty), ECHONL)
 145 #define L_NOFLSH(tty)   _L_FLAG((tty), NOFLSH)
 146 #define L_TOSTOP(tty)   _L_FLAG((tty), TOSTOP)
 147 #define L_ECHOCTL(tty)  _L_FLAG((tty), ECHOCTL)
 148 #define L_ECHOPRT(tty)  _L_FLAG((tty), ECHOPRT)
 149 #define L_ECHOKE(tty)   _L_FLAG((tty), ECHOKE)
 150 #define L_FLUSHO(tty)   _L_FLAG((tty), FLUSHO)
 151 #define L_PENDIN(tty)   _L_FLAG((tty), PENDIN)
 152 #define L_IEXTEN(tty)   _L_FLAG((tty), IEXTEN)
 153 #define L_EXTPROC(tty)  _L_FLAG((tty), EXTPROC)
 154
 155 struct device;
 156 struct signal_struct;
 157
 158 /*
 159  * Port level information. Each device keeps its own port level information
 160  * so provide a common structure for those ports wanting to use common support
 161  * routines.
 162  *
 163  * The tty port has a different lifetime to the tty so must be kept apart.
 164  * In addition be careful as tty -> port mappings are valid for the life
 165  * of the tty object but in many cases port -> tty mappings are valid only
 166  * until a hangup so don't use the wrong path.
 167  */
 168
 169 struct tty_port;
 170
 171 struct tty_port_operations {
 172         /* Return 1 if the carrier is raised */
 173         int (*carrier_raised)(struct tty_port *port);
 174         /* Control the DTR line */
 175         void (*dtr_rts)(struct tty_port *port, int raise);
 176         /* Called when the last close completes or a hangup finishes
 177            IFF the port was initialized. Do not use to free resources. Called
 178            under the port mutex to serialize against activate/shutdowns */
 179         void (*shutdown)(struct tty_port *port);
 180         void (*drop)(struct tty_port *port);
 181         /* Called under the port mutex from tty_port_open, serialized using
 182            the port mutex */
 183         /* FIXME: long term getting the tty argument *out* of this would be
 184            good for consoles */
 185         int (*activate)(struct tty_port *port, struct tty_struct *tty);
 186         /* Called on the final put of a port */
 187         void (*destruct)(struct tty_port *port);
 188 };
 189
 190 struct tty_port {
 191         struct tty_bufhead      buf;            /* Locked internally */
 192         struct tty_struct       *tty;           /* Back pointer */
 193         struct tty_struct       *itty;          /* internal back ptr */
 194         const struct tty_port_operations *ops;  /* Port operations */
 195         spinlock_t              lock;           /* Lock protecting tty field */
 196         int                     blocked_open;   /* Waiting to open */
 197         int                     count;          /* Usage count */
 198         wait_queue_head_t       open_wait;      /* Open waiters */
 199         wait_queue_head_t       close_wait;     /* Close waiters */
 200         wait_queue_head_t       delta_msr_wait; /* Modem status change */
 201         unsigned long           flags;          /* TTY flags ASY_*/
 202         unsigned long           iflags;         /* TTYP_ internal flags */
 203 #define TTYP_FLUSHING                   1  /* Flushing to ldisc in progress */
 204 #define TTYP_FLUSHPENDING               2  /* Queued buffer flush pending */
 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
 230 struct tty_operations;
 231
 232 struct 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 mutex ldisc_mutex;
 242         struct tty_ldisc *ldisc;
 243
 244         struct mutex atomic_write_lock;
 245         struct mutex legacy_mutex;
 246         struct mutex termios_mutex;
 247         spinlock_t ctrl_lock;
 248         /* Termios values are protected by the termios mutex */
 249         struct ktermios termios, termios_locked;
 250         struct termiox *termiox;        /* May be NULL for unsupported */
 251         char name[64];
 252         struct pid *pgrp;               /* Protected by ctrl lock */
 253         struct pid *session;
 254         unsigned long flags;
 255         int count;
 256         struct winsize winsize;         /* termios mutex */
 257         unsigned char stopped:1, hw_stopped:1, flow_stopped:1, packet:1;
 258         unsigned char ctrl_status;      /* ctrl_lock */
 259         unsigned int receive_room;      /* Bytes free for queue */
 260         int flow_change;
 261
 262         struct tty_struct *link;
 263         struct fasync_struct *fasync;
 264         int alt_speed;          /* For magic substitution of 38400 bps */
 265         wait_queue_head_t write_wait;
 266         wait_queue_head_t read_wait;
 267         struct work_struct hangup_work;
 268         void *disc_data;
 269         void *driver_data;
 270         struct list_head tty_files;
 271
 272 #define N_TTY_BUF_SIZE 4096
 273
 274         unsigned char closing:1;
 275         unsigned short minimum_to_wake;
 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 */
 284 struct 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_PUSH                6       /* n_tty private */
 308 #define TTY_CLOSING             7       /* ->close() in progress */
 309 #define TTY_LDISC               9       /* Line discipline attached */
 310 #define TTY_LDISC_CHANGING      10      /* Line discipline changing */
 311 #define TTY_LDISC_OPEN          11      /* Line discipline is open */
 312 #define TTY_HW_COOK_OUT         14      /* Hardware can do output cooking */
 313 #define TTY_HW_COOK_IN          15      /* Hardware can do input cooking */
 314 #define TTY_PTY_LOCK            16      /* pty private */
 315 #define TTY_NO_WRITE_SPLIT      17      /* Preserve write boundaries to driver */
 316 #define TTY_HUPPED              18      /* Post driver->hangup() */
 317 #define TTY_HUPPING             21      /* ->hangup() in progress */
 318 #define TTY_LDISC_HALTED        22      /* Line discipline is halted */
 319
 320 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
 321
 322 /* Values for tty->flow_change */
 323 #define TTY_THROTTLE_SAFE 1
 324 #define TTY_UNTHROTTLE_SAFE 2
 325
 326 static inline void __tty_set_flow_change(struct tty_struct *tty, int val)
 327 {
 328         tty->flow_change = val;
 329 }
 330
 331 static inline void tty_set_flow_change(struct tty_struct *tty, int val)
 332 {
 333         tty->flow_change = val;
 334         smp_mb();
 335 }
 336
 337 #ifdef CONFIG_TTY
 338 extern void console_init(void);
 339 extern void tty_kref_put(struct tty_struct *tty);
 340 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
 341 extern void tty_vhangup_self(void);
 342 extern void disassociate_ctty(int priv);
 343 extern dev_t tty_devnum(struct tty_struct *tty);
 344 extern void proc_clear_tty(struct task_struct *p);
 345 extern struct tty_struct *get_current_tty(void);
 346 /* tty_io.c */
 347 extern int __init tty_init(void);
 348 #else
 349 static inline void console_init(void)
 350 { }
 351 static inline void tty_kref_put(struct tty_struct *tty)
 352 { }
 353 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
 354 { return NULL; }
 355 static inline void tty_vhangup_self(void)
 356 { }
 357 static inline void disassociate_ctty(int priv)
 358 { }
 359 static inline dev_t tty_devnum(struct tty_struct *tty)
 360 { return 0; }
 361 static inline void proc_clear_tty(struct task_struct *p)
 362 { }
 363 static inline struct tty_struct *get_current_tty(void)
 364 { return NULL; }
 365 /* tty_io.c */
 366 static inline int __init tty_init(void)
 367 { return 0; }
 368 #endif
 369
 370 extern void tty_write_flush(struct tty_struct *);
 371
 372 extern struct ktermios tty_std_termios;
 373
 374 extern int vcs_init(void);
 375
 376 extern struct class *tty_class;
 377
 378 /**
 379  *      tty_kref_get            -       get a tty reference
 380  *      @tty: tty device
 381  *
 382  *      Return a new reference to a tty object. The caller must hold
 383  *      sufficient locks/counts to ensure that their existing reference cannot
 384  *      go away
 385  */
 386
 387 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 388 {
 389         if (tty)
 390                 kref_get(&tty->kref);
 391         return tty;
 392 }
 393
 394 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
 395                               const char *routine);
 396 extern char *tty_name(struct tty_struct *tty, char *buf);
 397 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
 398 extern int tty_check_change(struct tty_struct *tty);
 399 extern void stop_tty(struct tty_struct *tty);
 400 extern void start_tty(struct tty_struct *tty);
 401 extern int tty_register_driver(struct tty_driver *driver);
 402 extern int tty_unregister_driver(struct tty_driver *driver);
 403 extern struct device *tty_register_device(struct tty_driver *driver,
 404                                           unsigned index, struct device *dev);
 405 extern struct device *tty_register_device_attr(struct tty_driver *driver,
 406                                 unsigned index, struct device *device,
 407                                 void *drvdata,
 408                                 const struct attribute_group **attr_grp);
 409 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
 410 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
 411                              int buflen);
 412 extern void tty_write_message(struct tty_struct *tty, char *msg);
 413 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
 414 extern int tty_chars_in_buffer(struct tty_struct *tty);
 415 extern int tty_write_room(struct tty_struct *tty);
 416 extern void tty_driver_flush_buffer(struct tty_struct *tty);
 417 extern void tty_throttle(struct tty_struct *tty);
 418 extern void tty_unthrottle(struct tty_struct *tty);
 419 extern int tty_throttle_safe(struct tty_struct *tty);
 420 extern int tty_unthrottle_safe(struct tty_struct *tty);
 421 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 422 extern void tty_driver_remove_tty(struct tty_driver *driver,
 423                                   struct tty_struct *tty);
 424 extern void tty_free_termios(struct tty_struct *tty);
 425 extern int is_current_pgrp_orphaned(void);
 426 extern int is_ignored(int sig);
 427 extern int tty_signal(int sig, struct tty_struct *tty);
 428 extern void tty_hangup(struct tty_struct *tty);
 429 extern void tty_vhangup(struct tty_struct *tty);
 430 extern void tty_vhangup_locked(struct tty_struct *tty);
 431 extern void tty_unhangup(struct file *filp);
 432 extern int tty_hung_up_p(struct file *filp);
 433 extern void do_SAK(struct tty_struct *tty);
 434 extern void __do_SAK(struct tty_struct *tty);
 435 extern void no_tty(void);
 436 extern void tty_flush_to_ldisc(struct tty_struct *tty);
 437 extern void tty_buffer_free_all(struct tty_port *port);
 438 extern void tty_buffer_flush(struct tty_struct *tty);
 439 extern void tty_buffer_init(struct tty_port *port);
 440 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
 441 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
 442 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
 443                                                 speed_t ibaud, speed_t obaud);
 444 extern void tty_encode_baud_rate(struct tty_struct *tty,
 445                                                 speed_t ibaud, speed_t obaud);
 446
 447 /**
 448  *      tty_get_baud_rate       -       get tty bit rates
 449  *      @tty: tty to query
 450  *
 451  *      Returns the baud rate as an integer for this terminal. The
 452  *      termios lock must be held by the caller and the terminal bit
 453  *      flags may be updated.
 454  *
 455  *      Locking: none
 456  */
 457 static inline speed_t tty_get_baud_rate(struct tty_struct *tty)
 458 {
 459         return tty_termios_baud_rate(&tty->termios);
 460 }
 461
 462 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 463 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
 464 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 465
 466 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
 467 extern void tty_ldisc_deref(struct tty_ldisc *);
 468 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
 469 extern void tty_ldisc_hangup(struct tty_struct *tty);
 470 extern const struct file_operations tty_ldiscs_proc_fops;
 471
 472 extern void tty_wakeup(struct tty_struct *tty);
 473 extern void tty_ldisc_flush(struct tty_struct *tty);
 474
 475 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 476 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 477                         unsigned int cmd, unsigned long arg);
 478 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 479 extern void tty_default_fops(struct file_operations *fops);
 480 extern struct tty_struct *alloc_tty_struct(void);
 481 extern int tty_alloc_file(struct file *file);
 482 extern void tty_add_file(struct tty_struct *tty, struct file *file);
 483 extern void tty_free_file(struct file *file);
 484 extern void free_tty_struct(struct tty_struct *tty);
 485 extern void initialize_tty_struct(struct tty_struct *tty,
 486                 struct tty_driver *driver, int idx);
 487 extern void deinitialize_tty_struct(struct tty_struct *tty);
 488 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
 489 extern int tty_release(struct inode *inode, struct file *filp);
 490 extern int tty_init_termios(struct tty_struct *tty);
 491 extern int tty_standard_install(struct tty_driver *driver,
 492                 struct tty_struct *tty);
 493
 494 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
 495 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
 496
 497 extern struct mutex tty_mutex;
 498 extern spinlock_t tty_files_lock;
 499
 500 extern void tty_write_unlock(struct tty_struct *tty);
 501 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 502 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
 503
 504 extern void tty_port_init(struct tty_port *port);
 505 extern void tty_port_link_device(struct tty_port *port,
 506                 struct tty_driver *driver, unsigned index);
 507 extern struct device *tty_port_register_device(struct tty_port *port,
 508                 struct tty_driver *driver, unsigned index,
 509                 struct device *device);
 510 extern struct device *tty_port_register_device_attr(struct tty_port *port,
 511                 struct tty_driver *driver, unsigned index,
 512                 struct device *device, void *drvdata,
 513                 const struct attribute_group **attr_grp);
 514 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 515 extern void tty_port_free_xmit_buf(struct tty_port *port);
 516 extern void tty_port_destroy(struct tty_port *port);
 517 extern void tty_port_put(struct tty_port *port);
 518
 519 static inline struct tty_port *tty_port_get(struct tty_port *port)
 520 {
 521         if (port)
 522                 kref_get(&port->kref);
 523         return port;
 524 }
 525
 526 /* If the cts flow control is enabled, return true. */
 527 static inline bool tty_port_cts_enabled(struct tty_port *port)
 528 {
 529         return port->flags & ASYNC_CTS_FLOW;
 530 }
 531
 532 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 533 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 534 extern int tty_port_carrier_raised(struct tty_port *port);
 535 extern void tty_port_raise_dtr_rts(struct tty_port *port);
 536 extern void tty_port_lower_dtr_rts(struct tty_port *port);
 537 extern void tty_port_hangup(struct tty_port *port);
 538 extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal);
 539 extern void tty_port_tty_wakeup(struct tty_port *port);
 540 extern int tty_port_block_til_ready(struct tty_port *port,
 541                                 struct tty_struct *tty, struct file *filp);
 542 extern int tty_port_close_start(struct tty_port *port,
 543                                 struct tty_struct *tty, struct file *filp);
 544 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
 545 extern void tty_port_close(struct tty_port *port,
 546                                 struct tty_struct *tty, struct file *filp);
 547 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
 548                                 struct tty_struct *tty);
 549 extern int tty_port_open(struct tty_port *port,
 550                                 struct tty_struct *tty, struct file *filp);
 551 static inline int tty_port_users(struct tty_port *port)
 552 {
 553         return port->count + port->blocked_open;
 554 }
 555
 556 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
 557 extern int tty_unregister_ldisc(int disc);
 558 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
 559 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
 560 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
 561 extern void tty_ldisc_init(struct tty_struct *tty);
 562 extern void tty_ldisc_deinit(struct tty_struct *tty);
 563 extern void tty_ldisc_begin(void);
 564
 565
 566 /* n_tty.c */
 567 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
 568 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 569
 570 /* tty_audit.c */
 571 #ifdef CONFIG_AUDIT
 572 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
 573                                size_t size, unsigned icanon);
 574 extern void tty_audit_exit(void);
 575 extern void tty_audit_fork(struct signal_struct *sig);
 576 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
 577 extern void tty_audit_push(struct tty_struct *tty);
 578 extern int tty_audit_push_current(void);
 579 #else
 580 static inline void tty_audit_add_data(struct tty_struct *tty,
 581                 unsigned char *data, size_t size, unsigned icanon)
 582 {
 583 }
 584 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
 585 {
 586 }
 587 static inline void tty_audit_exit(void)
 588 {
 589 }
 590 static inline void tty_audit_fork(struct signal_struct *sig)
 591 {
 592 }
 593 static inline void tty_audit_push(struct tty_struct *tty)
 594 {
 595 }
 596 static inline int tty_audit_push_current(void)
 597 {
 598         return 0;
 599 }
 600 #endif
 601
 602 /* tty_ioctl.c */
 603 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 604                        unsigned int cmd, unsigned long arg);
 605 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
 606                        unsigned int cmd, unsigned long arg);
 607
 608 /* serial.c */
 609
 610 extern void serial_console_init(void);
 611
 612 /* pcxx.c */
 613
 614 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
 615
 616 /* vt.c */
 617
 618 extern int vt_ioctl(struct tty_struct *tty,
 619                     unsigned int cmd, unsigned long arg);
 620
 621 extern long vt_compat_ioctl(struct tty_struct *tty,
 622                      unsigned int cmd, unsigned long arg);
 623
 624 /* tty_mutex.c */
 625 /* functions for preparation of BKL removal */
 626 extern void __lockfunc tty_lock(struct tty_struct *tty);
 627 extern void __lockfunc tty_unlock(struct tty_struct *tty);
 628 extern void __lockfunc tty_lock_pair(struct tty_struct *tty,
 629                                 struct tty_struct *tty2);
 630 extern void __lockfunc tty_unlock_pair(struct tty_struct *tty,
 631                                 struct tty_struct *tty2);
 632
 633 /*
 634  * this shall be called only from where BTM is held (like close)
 635  *
 636  * We need this to ensure nobody waits for us to finish while we are waiting.
 637  * Without this we were encountering system stalls.
 638  *
 639  * This should be indeed removed with BTM removal later.
 640  *
 641  * Locking: BTM required. Nobody is allowed to hold port->mutex.
 642  */
 643 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
 644                 long timeout)
 645 {
 646         tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */
 647         tty_wait_until_sent(tty, timeout);
 648         tty_lock(tty);
 649 }
 650
 651 /*
 652  * wait_event_interruptible_tty -- wait for a condition with the tty lock held
 653  *
 654  * The condition we are waiting for might take a long time to
 655  * become true, or might depend on another thread taking the
 656  * BTM. In either case, we need to drop the BTM to guarantee
 657  * forward progress. This is a leftover from the conversion
 658  * from the BKL and should eventually get removed as the BTM
 659  * falls out of use.
 660  *
 661  * Do not use in new code.
 662  */
 663 #define wait_event_interruptible_tty(tty, wq, condition)                \
 664 ({                                                                      \
 665         int __ret = 0;                                                  \
 666         if (!(condition)) {                                             \
 667                 __wait_event_interruptible_tty(tty, wq, condition, __ret);      \
 668         }                                                               \
 669         __ret;                                                          \
 670 })
 671
 672 #define __wait_event_interruptible_tty(tty, wq, condition, ret)         \
 673 do {                                                                    \
 674         DEFINE_WAIT(__wait);                                            \
 675                                                                         \
 676         for (;;) {                                                      \
 677                 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);      \
 678                 if (condition)                                          \
 679                         break;                                          \
 680                 if (!signal_pending(current)) {                         \
 681                         tty_unlock(tty);                                        \
 682                         schedule();                                     \
 683                         tty_lock(tty);                                  \
 684                         continue;                                       \
 685                 }                                                       \
 686                 ret = -ERESTARTSYS;                                     \
 687                 break;                                                  \
 688         }                                                               \
 689         finish_wait(&wq, &__wait);                                      \
 690 } while (0)
 691
 692 #ifdef CONFIG_PROC_FS
 693 extern void proc_tty_register_driver(struct tty_driver *);
 694 extern void proc_tty_unregister_driver(struct tty_driver *);
 695 #else
 696 static inline void proc_tty_register_driver(struct tty_driver *d) {}
 697 static inline void proc_tty_unregister_driver(struct tty_driver *d) {}
 698 #endif
 699
 700 #endif