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 warned:1;
 259         unsigned char ctrl_status;      /* ctrl_lock */
 260         unsigned int receive_room;      /* Bytes free for queue */
 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
 319 #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty))
 320
 321 #ifdef CONFIG_TTY
 322 extern void console_init(void);
 323 extern void tty_kref_put(struct tty_struct *tty);
 324 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
 325 extern void tty_vhangup_self(void);
 326 extern void disassociate_ctty(int priv);
 327 extern dev_t tty_devnum(struct tty_struct *tty);
 328 extern void proc_clear_tty(struct task_struct *p);
 329 extern struct tty_struct *get_current_tty(void);
 330 /* tty_io.c */
 331 extern int __init tty_init(void);
 332 #else
 333 static inline void console_init(void)
 334 { }
 335 static inline void tty_kref_put(struct tty_struct *tty)
 336 { }
 337 static inline struct pid *tty_get_pgrp(struct tty_struct *tty)
 338 { return NULL; }
 339 static inline void tty_vhangup_self(void)
 340 { }
 341 static inline void disassociate_ctty(int priv)
 342 { }
 343 static inline dev_t tty_devnum(struct tty_struct *tty)
 344 { return 0; }
 345 static inline void proc_clear_tty(struct task_struct *p)
 346 { }
 347 static inline struct tty_struct *get_current_tty(void)
 348 { return NULL; }
 349 /* tty_io.c */
 350 static inline int __init tty_init(void)
 351 { return 0; }
 352 #endif
 353
 354 extern void tty_write_flush(struct tty_struct *);
 355
 356 extern struct ktermios tty_std_termios;
 357
 358 extern int vcs_init(void);
 359
 360 extern struct class *tty_class;
 361
 362 /**
 363  *      tty_kref_get            -       get a tty reference
 364  *      @tty: tty device
 365  *
 366  *      Return a new reference to a tty object. The caller must hold
 367  *      sufficient locks/counts to ensure that their existing reference cannot
 368  *      go away
 369  */
 370
 371 static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
 372 {
 373         if (tty)
 374                 kref_get(&tty->kref);
 375         return tty;
 376 }
 377
 378 extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
 379                               const char *routine);
 380 extern char *tty_name(struct tty_struct *tty, char *buf);
 381 extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
 382 extern int tty_check_change(struct tty_struct *tty);
 383 extern void stop_tty(struct tty_struct *tty);
 384 extern void start_tty(struct tty_struct *tty);
 385 extern int tty_register_driver(struct tty_driver *driver);
 386 extern int tty_unregister_driver(struct tty_driver *driver);
 387 extern struct device *tty_register_device(struct tty_driver *driver,
 388                                           unsigned index, struct device *dev);
 389 extern struct device *tty_register_device_attr(struct tty_driver *driver,
 390                                 unsigned index, struct device *device,
 391                                 void *drvdata,
 392                                 const struct attribute_group **attr_grp);
 393 extern void tty_unregister_device(struct tty_driver *driver, unsigned index);
 394 extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
 395                              int buflen);
 396 extern void tty_write_message(struct tty_struct *tty, char *msg);
 397 extern int tty_put_char(struct tty_struct *tty, unsigned char c);
 398 extern int tty_chars_in_buffer(struct tty_struct *tty);
 399 extern int tty_write_room(struct tty_struct *tty);
 400 extern void tty_driver_flush_buffer(struct tty_struct *tty);
 401 extern void tty_throttle(struct tty_struct *tty);
 402 extern void tty_unthrottle(struct tty_struct *tty);
 403 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 404 extern void tty_driver_remove_tty(struct tty_driver *driver,
 405                                   struct tty_struct *tty);
 406 extern void tty_free_termios(struct tty_struct *tty);
 407 extern int is_current_pgrp_orphaned(void);
 408 extern int is_ignored(int sig);
 409 extern int tty_signal(int sig, struct tty_struct *tty);
 410 extern void tty_hangup(struct tty_struct *tty);
 411 extern void tty_vhangup(struct tty_struct *tty);
 412 extern void tty_vhangup_locked(struct tty_struct *tty);
 413 extern void tty_unhangup(struct file *filp);
 414 extern int tty_hung_up_p(struct file *filp);
 415 extern void do_SAK(struct tty_struct *tty);
 416 extern void __do_SAK(struct tty_struct *tty);
 417 extern void no_tty(void);
 418 extern void tty_flush_to_ldisc(struct tty_struct *tty);
 419 extern void tty_buffer_free_all(struct tty_port *port);
 420 extern void tty_buffer_flush(struct tty_struct *tty);
 421 extern void tty_buffer_init(struct tty_port *port);
 422 extern speed_t tty_get_baud_rate(struct tty_struct *tty);
 423 extern speed_t tty_termios_baud_rate(struct ktermios *termios);
 424 extern speed_t tty_termios_input_baud_rate(struct ktermios *termios);
 425 extern void tty_termios_encode_baud_rate(struct ktermios *termios,
 426                                                 speed_t ibaud, speed_t obaud);
 427 extern void tty_encode_baud_rate(struct tty_struct *tty,
 428                                                 speed_t ibaud, speed_t obaud);
 429 extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old);
 430 extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b);
 431 extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt);
 432
 433 extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *);
 434 extern void tty_ldisc_deref(struct tty_ldisc *);
 435 extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *);
 436 extern void tty_ldisc_hangup(struct tty_struct *tty);
 437 extern const struct file_operations tty_ldiscs_proc_fops;
 438
 439 extern void tty_wakeup(struct tty_struct *tty);
 440 extern void tty_ldisc_flush(struct tty_struct *tty);
 441
 442 extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 443 extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
 444                         unsigned int cmd, unsigned long arg);
 445 extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg);
 446 extern void tty_default_fops(struct file_operations *fops);
 447 extern struct tty_struct *alloc_tty_struct(void);
 448 extern int tty_alloc_file(struct file *file);
 449 extern void tty_add_file(struct tty_struct *tty, struct file *file);
 450 extern void tty_free_file(struct file *file);
 451 extern void free_tty_struct(struct tty_struct *tty);
 452 extern void initialize_tty_struct(struct tty_struct *tty,
 453                 struct tty_driver *driver, int idx);
 454 extern void deinitialize_tty_struct(struct tty_struct *tty);
 455 extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx);
 456 extern int tty_release(struct inode *inode, struct file *filp);
 457 extern int tty_init_termios(struct tty_struct *tty);
 458 extern int tty_standard_install(struct tty_driver *driver,
 459                 struct tty_struct *tty);
 460
 461 extern struct tty_struct *tty_pair_get_tty(struct tty_struct *tty);
 462 extern struct tty_struct *tty_pair_get_pty(struct tty_struct *tty);
 463
 464 extern struct mutex tty_mutex;
 465 extern spinlock_t tty_files_lock;
 466
 467 extern void tty_write_unlock(struct tty_struct *tty);
 468 extern int tty_write_lock(struct tty_struct *tty, int ndelay);
 469 #define tty_is_writelocked(tty)  (mutex_is_locked(&tty->atomic_write_lock))
 470
 471 extern void tty_port_init(struct tty_port *port);
 472 extern void tty_port_link_device(struct tty_port *port,
 473                 struct tty_driver *driver, unsigned index);
 474 extern struct device *tty_port_register_device(struct tty_port *port,
 475                 struct tty_driver *driver, unsigned index,
 476                 struct device *device);
 477 extern struct device *tty_port_register_device_attr(struct tty_port *port,
 478                 struct tty_driver *driver, unsigned index,
 479                 struct device *device, void *drvdata,
 480                 const struct attribute_group **attr_grp);
 481 extern int tty_port_alloc_xmit_buf(struct tty_port *port);
 482 extern void tty_port_free_xmit_buf(struct tty_port *port);
 483 extern void tty_port_destroy(struct tty_port *port);
 484 extern void tty_port_put(struct tty_port *port);
 485
 486 static inline struct tty_port *tty_port_get(struct tty_port *port)
 487 {
 488         if (port)
 489                 kref_get(&port->kref);
 490         return port;
 491 }
 492
 493 /* If the cts flow control is enabled, return true. */
 494 static inline bool tty_port_cts_enabled(struct tty_port *port)
 495 {
 496         return port->flags & ASYNC_CTS_FLOW;
 497 }
 498
 499 extern struct tty_struct *tty_port_tty_get(struct tty_port *port);
 500 extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty);
 501 extern int tty_port_carrier_raised(struct tty_port *port);
 502 extern void tty_port_raise_dtr_rts(struct tty_port *port);
 503 extern void tty_port_lower_dtr_rts(struct tty_port *port);
 504 extern void tty_port_hangup(struct tty_port *port);
 505 extern int tty_port_block_til_ready(struct tty_port *port,
 506                                 struct tty_struct *tty, struct file *filp);
 507 extern int tty_port_close_start(struct tty_port *port,
 508                                 struct tty_struct *tty, struct file *filp);
 509 extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty);
 510 extern void tty_port_close(struct tty_port *port,
 511                                 struct tty_struct *tty, struct file *filp);
 512 extern int tty_port_install(struct tty_port *port, struct tty_driver *driver,
 513                                 struct tty_struct *tty);
 514 extern int tty_port_open(struct tty_port *port,
 515                                 struct tty_struct *tty, struct file *filp);
 516 static inline int tty_port_users(struct tty_port *port)
 517 {
 518         return port->count + port->blocked_open;
 519 }
 520
 521 extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc);
 522 extern int tty_unregister_ldisc(int disc);
 523 extern int tty_set_ldisc(struct tty_struct *tty, int ldisc);
 524 extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty);
 525 extern void tty_ldisc_release(struct tty_struct *tty, struct tty_struct *o_tty);
 526 extern void tty_ldisc_init(struct tty_struct *tty);
 527 extern void tty_ldisc_deinit(struct tty_struct *tty);
 528 extern void tty_ldisc_begin(void);
 529 /* This last one is just for the tty layer internals and shouldn't be used elsewhere */
 530 extern void tty_ldisc_enable(struct tty_struct *tty);
 531
 532
 533 /* n_tty.c */
 534 extern struct tty_ldisc_ops tty_ldisc_N_TTY;
 535 extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops);
 536
 537 /* tty_audit.c */
 538 #ifdef CONFIG_AUDIT
 539 extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data,
 540                                size_t size, unsigned icanon);
 541 extern void tty_audit_exit(void);
 542 extern void tty_audit_fork(struct signal_struct *sig);
 543 extern void tty_audit_tiocsti(struct tty_struct *tty, char ch);
 544 extern void tty_audit_push(struct tty_struct *tty);
 545 extern int tty_audit_push_task(struct task_struct *tsk,
 546                                kuid_t loginuid, u32 sessionid);
 547 #else
 548 static inline void tty_audit_add_data(struct tty_struct *tty,
 549                 unsigned char *data, size_t size, unsigned icanon)
 550 {
 551 }
 552 static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch)
 553 {
 554 }
 555 static inline void tty_audit_exit(void)
 556 {
 557 }
 558 static inline void tty_audit_fork(struct signal_struct *sig)
 559 {
 560 }
 561 static inline void tty_audit_push(struct tty_struct *tty)
 562 {
 563 }
 564 static inline int tty_audit_push_task(struct task_struct *tsk,
 565                                       kuid_t loginuid, u32 sessionid)
 566 {
 567         return 0;
 568 }
 569 #endif
 570
 571 /* tty_ioctl.c */
 572 extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
 573                        unsigned int cmd, unsigned long arg);
 574 extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file,
 575                        unsigned int cmd, unsigned long arg);
 576
 577 /* serial.c */
 578
 579 extern void serial_console_init(void);
 580
 581 /* pcxx.c */
 582
 583 extern int pcxe_open(struct tty_struct *tty, struct file *filp);
 584
 585 /* vt.c */
 586
 587 extern int vt_ioctl(struct tty_struct *tty,
 588                     unsigned int cmd, unsigned long arg);
 589
 590 extern long vt_compat_ioctl(struct tty_struct *tty,
 591                      unsigned int cmd, unsigned long arg);
 592
 593 /* tty_mutex.c */
 594 /* functions for preparation of BKL removal */
 595 extern void __lockfunc tty_lock(struct tty_struct *tty);
 596 extern void __lockfunc tty_unlock(struct tty_struct *tty);
 597 extern void __lockfunc tty_lock_pair(struct tty_struct *tty,
 598                                 struct tty_struct *tty2);
 599 extern void __lockfunc tty_unlock_pair(struct tty_struct *tty,
 600                                 struct tty_struct *tty2);
 601
 602 /*
 603  * this shall be called only from where BTM is held (like close)
 604  *
 605  * We need this to ensure nobody waits for us to finish while we are waiting.
 606  * Without this we were encountering system stalls.
 607  *
 608  * This should be indeed removed with BTM removal later.
 609  *
 610  * Locking: BTM required. Nobody is allowed to hold port->mutex.
 611  */
 612 static inline void tty_wait_until_sent_from_close(struct tty_struct *tty,
 613                 long timeout)
 614 {
 615         tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */
 616         tty_wait_until_sent(tty, timeout);
 617         tty_lock(tty);
 618 }
 619
 620 /*
 621  * wait_event_interruptible_tty -- wait for a condition with the tty lock held
 622  *
 623  * The condition we are waiting for might take a long time to
 624  * become true, or might depend on another thread taking the
 625  * BTM. In either case, we need to drop the BTM to guarantee
 626  * forward progress. This is a leftover from the conversion
 627  * from the BKL and should eventually get removed as the BTM
 628  * falls out of use.
 629  *
 630  * Do not use in new code.
 631  */
 632 #define wait_event_interruptible_tty(tty, wq, condition)                \
 633 ({                                                                      \
 634         int __ret = 0;                                                  \
 635         if (!(condition)) {                                             \
 636                 __wait_event_interruptible_tty(tty, wq, condition, __ret);      \
 637         }                                                               \
 638         __ret;                                                          \
 639 })
 640
 641 #define __wait_event_interruptible_tty(tty, wq, condition, ret)         \
 642 do {                                                                    \
 643         DEFINE_WAIT(__wait);                                            \
 644                                                                         \
 645         for (;;) {                                                      \
 646                 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);      \
 647                 if (condition)                                          \
 648                         break;                                          \
 649                 if (!signal_pending(current)) {                         \
 650                         tty_unlock(tty);                                        \
 651                         schedule();                                     \
 652                         tty_lock(tty);                                  \
 653                         continue;                                       \
 654                 }                                                       \
 655                 ret = -ERESTARTSYS;                                     \
 656                 break;                                                  \
 657         }                                                               \
 658         finish_wait(&wq, &__wait);                                      \
 659 } while (0)
 660
 661
 662 #endif