| 1 | #ifndef _LINUX_TTY_H |
| 2 | #define _LINUX_TTY_H |
| 3 | |
| 4 | #include <linux/fs.h> |
| 5 | #include <linux/major.h> |
| 6 | #include <linux/termios.h> |
| 7 | #include <linux/workqueue.h> |
| 8 | #include <linux/tty_driver.h> |
| 9 | #include <linux/tty_ldisc.h> |
| 10 | #include <linux/mutex.h> |
| 11 | #include <linux/tty_flags.h> |
| 12 | #include <uapi/linux/tty.h> |
| 13 | #include <linux/rwsem.h> |
| 14 | #include <linux/llist.h> |
| 15 | |
| 16 | |
| 17 | /* |
| 18 | * Lock subclasses for tty locks |
| 19 | * |
| 20 | * TTY_LOCK_NORMAL is for normal ttys and master ptys. |
| 21 | * TTY_LOCK_SLAVE is for slave ptys only. |
| 22 | * |
| 23 | * Lock subclasses are necessary for handling nested locking with pty pairs. |
| 24 | * tty locks which use nested locking: |
| 25 | * |
| 26 | * legacy_mutex - Nested tty locks are necessary for releasing pty pairs. |
| 27 | * The stable lock order is master pty first, then slave pty. |
| 28 | * termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem. |
| 29 | * Subclassing this lock enables the slave pty to hold its |
| 30 | * termios_rwsem when claiming the master tty_buffer lock. |
| 31 | * tty_buffer lock - slave ptys can claim nested buffer lock when handling |
| 32 | * signal chars. The stable lock order is slave pty, then |
| 33 | * master. |
| 34 | */ |
| 35 | |
| 36 | enum { |
| 37 | TTY_LOCK_NORMAL = 0, |
| 38 | TTY_LOCK_SLAVE, |
| 39 | }; |
| 40 | |
| 41 | /* |
| 42 | * (Note: the *_driver.minor_start values 1, 64, 128, 192 are |
| 43 | * hardcoded at present.) |
| 44 | */ |
| 45 | #define NR_UNIX98_PTY_DEFAULT 4096 /* Default maximum for Unix98 ptys */ |
| 46 | #define NR_UNIX98_PTY_RESERVE 1024 /* Default reserve for main devpts */ |
| 47 | #define NR_UNIX98_PTY_MAX (1 << MINORBITS) /* Absolute limit */ |
| 48 | |
| 49 | /* |
| 50 | * This character is the same as _POSIX_VDISABLE: it cannot be used as |
| 51 | * a c_cc[] character, but indicates that a particular special character |
| 52 | * isn't in use (eg VINTR has no character etc) |
| 53 | */ |
| 54 | #define __DISABLED_CHAR '\0' |
| 55 | |
| 56 | struct tty_buffer { |
| 57 | union { |
| 58 | struct tty_buffer *next; |
| 59 | struct llist_node free; |
| 60 | }; |
| 61 | int used; |
| 62 | int size; |
| 63 | int commit; |
| 64 | int read; |
| 65 | int flags; |
| 66 | /* Data points here */ |
| 67 | unsigned long data[0]; |
| 68 | }; |
| 69 | |
| 70 | /* Values for .flags field of tty_buffer */ |
| 71 | #define TTYB_NORMAL 1 /* buffer has no flags buffer */ |
| 72 | |
| 73 | static inline unsigned char *char_buf_ptr(struct tty_buffer *b, int ofs) |
| 74 | { |
| 75 | return ((unsigned char *)b->data) + ofs; |
| 76 | } |
| 77 | |
| 78 | static inline char *flag_buf_ptr(struct tty_buffer *b, int ofs) |
| 79 | { |
| 80 | return (char *)char_buf_ptr(b, ofs) + b->size; |
| 81 | } |
| 82 | |
| 83 | struct tty_bufhead { |
| 84 | struct tty_buffer *head; /* Queue head */ |
| 85 | struct work_struct work; |
| 86 | struct mutex lock; |
| 87 | atomic_t priority; |
| 88 | struct tty_buffer sentinel; |
| 89 | struct llist_head free; /* Free queue head */ |
| 90 | atomic_t mem_used; /* In-use buffers excluding free list */ |
| 91 | int mem_limit; |
| 92 | struct tty_buffer *tail; /* Active buffer */ |
| 93 | }; |
| 94 | /* |
| 95 | * When a break, frame error, or parity error happens, these codes are |
| 96 | * stuffed into the flags buffer. |
| 97 | */ |
| 98 | #define TTY_NORMAL 0 |
| 99 | #define TTY_BREAK 1 |
| 100 | #define TTY_FRAME 2 |
| 101 | #define TTY_PARITY 3 |
| 102 | #define TTY_OVERRUN 4 |
| 103 | |
| 104 | #define INTR_CHAR(tty) ((tty)->termios.c_cc[VINTR]) |
| 105 | #define QUIT_CHAR(tty) ((tty)->termios.c_cc[VQUIT]) |
| 106 | #define ERASE_CHAR(tty) ((tty)->termios.c_cc[VERASE]) |
| 107 | #define KILL_CHAR(tty) ((tty)->termios.c_cc[VKILL]) |
| 108 | #define EOF_CHAR(tty) ((tty)->termios.c_cc[VEOF]) |
| 109 | #define TIME_CHAR(tty) ((tty)->termios.c_cc[VTIME]) |
| 110 | #define MIN_CHAR(tty) ((tty)->termios.c_cc[VMIN]) |
| 111 | #define SWTC_CHAR(tty) ((tty)->termios.c_cc[VSWTC]) |
| 112 | #define START_CHAR(tty) ((tty)->termios.c_cc[VSTART]) |
| 113 | #define STOP_CHAR(tty) ((tty)->termios.c_cc[VSTOP]) |
| 114 | #define SUSP_CHAR(tty) ((tty)->termios.c_cc[VSUSP]) |
| 115 | #define EOL_CHAR(tty) ((tty)->termios.c_cc[VEOL]) |
| 116 | #define REPRINT_CHAR(tty) ((tty)->termios.c_cc[VREPRINT]) |
| 117 | #define DISCARD_CHAR(tty) ((tty)->termios.c_cc[VDISCARD]) |
| 118 | #define WERASE_CHAR(tty) ((tty)->termios.c_cc[VWERASE]) |
| 119 | #define LNEXT_CHAR(tty) ((tty)->termios.c_cc[VLNEXT]) |
| 120 | #define EOL2_CHAR(tty) ((tty)->termios.c_cc[VEOL2]) |
| 121 | |
| 122 | #define _I_FLAG(tty, f) ((tty)->termios.c_iflag & (f)) |
| 123 | #define _O_FLAG(tty, f) ((tty)->termios.c_oflag & (f)) |
| 124 | #define _C_FLAG(tty, f) ((tty)->termios.c_cflag & (f)) |
| 125 | #define _L_FLAG(tty, f) ((tty)->termios.c_lflag & (f)) |
| 126 | |
| 127 | #define I_IGNBRK(tty) _I_FLAG((tty), IGNBRK) |
| 128 | #define I_BRKINT(tty) _I_FLAG((tty), BRKINT) |
| 129 | #define I_IGNPAR(tty) _I_FLAG((tty), IGNPAR) |
| 130 | #define I_PARMRK(tty) _I_FLAG((tty), PARMRK) |
| 131 | #define I_INPCK(tty) _I_FLAG((tty), INPCK) |
| 132 | #define I_ISTRIP(tty) _I_FLAG((tty), ISTRIP) |
| 133 | #define I_INLCR(tty) _I_FLAG((tty), INLCR) |
| 134 | #define I_IGNCR(tty) _I_FLAG((tty), IGNCR) |
| 135 | #define I_ICRNL(tty) _I_FLAG((tty), ICRNL) |
| 136 | #define I_IUCLC(tty) _I_FLAG((tty), IUCLC) |
| 137 | #define I_IXON(tty) _I_FLAG((tty), IXON) |
| 138 | #define I_IXANY(tty) _I_FLAG((tty), IXANY) |
| 139 | #define I_IXOFF(tty) _I_FLAG((tty), IXOFF) |
| 140 | #define I_IMAXBEL(tty) _I_FLAG((tty), IMAXBEL) |
| 141 | #define I_IUTF8(tty) _I_FLAG((tty), IUTF8) |
| 142 | |
| 143 | #define O_OPOST(tty) _O_FLAG((tty), OPOST) |
| 144 | #define O_OLCUC(tty) _O_FLAG((tty), OLCUC) |
| 145 | #define O_ONLCR(tty) _O_FLAG((tty), ONLCR) |
| 146 | #define O_OCRNL(tty) _O_FLAG((tty), OCRNL) |
| 147 | #define O_ONOCR(tty) _O_FLAG((tty), ONOCR) |
| 148 | #define O_ONLRET(tty) _O_FLAG((tty), ONLRET) |
| 149 | #define O_OFILL(tty) _O_FLAG((tty), OFILL) |
| 150 | #define O_OFDEL(tty) _O_FLAG((tty), OFDEL) |
| 151 | #define O_NLDLY(tty) _O_FLAG((tty), NLDLY) |
| 152 | #define O_CRDLY(tty) _O_FLAG((tty), CRDLY) |
| 153 | #define O_TABDLY(tty) _O_FLAG((tty), TABDLY) |
| 154 | #define O_BSDLY(tty) _O_FLAG((tty), BSDLY) |
| 155 | #define O_VTDLY(tty) _O_FLAG((tty), VTDLY) |
| 156 | #define O_FFDLY(tty) _O_FLAG((tty), FFDLY) |
| 157 | |
| 158 | #define C_BAUD(tty) _C_FLAG((tty), CBAUD) |
| 159 | #define C_CSIZE(tty) _C_FLAG((tty), CSIZE) |
| 160 | #define C_CSTOPB(tty) _C_FLAG((tty), CSTOPB) |
| 161 | #define C_CREAD(tty) _C_FLAG((tty), CREAD) |
| 162 | #define C_PARENB(tty) _C_FLAG((tty), PARENB) |
| 163 | #define C_PARODD(tty) _C_FLAG((tty), PARODD) |
| 164 | #define C_HUPCL(tty) _C_FLAG((tty), HUPCL) |
| 165 | #define C_CLOCAL(tty) _C_FLAG((tty), CLOCAL) |
| 166 | #define C_CIBAUD(tty) _C_FLAG((tty), CIBAUD) |
| 167 | #define C_CRTSCTS(tty) _C_FLAG((tty), CRTSCTS) |
| 168 | #define C_CMSPAR(tty) _C_FLAG((tty), CMSPAR) |
| 169 | |
| 170 | #define L_ISIG(tty) _L_FLAG((tty), ISIG) |
| 171 | #define L_ICANON(tty) _L_FLAG((tty), ICANON) |
| 172 | #define L_XCASE(tty) _L_FLAG((tty), XCASE) |
| 173 | #define L_ECHO(tty) _L_FLAG((tty), ECHO) |
| 174 | #define L_ECHOE(tty) _L_FLAG((tty), ECHOE) |
| 175 | #define L_ECHOK(tty) _L_FLAG((tty), ECHOK) |
| 176 | #define L_ECHONL(tty) _L_FLAG((tty), ECHONL) |
| 177 | #define L_NOFLSH(tty) _L_FLAG((tty), NOFLSH) |
| 178 | #define L_TOSTOP(tty) _L_FLAG((tty), TOSTOP) |
| 179 | #define L_ECHOCTL(tty) _L_FLAG((tty), ECHOCTL) |
| 180 | #define L_ECHOPRT(tty) _L_FLAG((tty), ECHOPRT) |
| 181 | #define L_ECHOKE(tty) _L_FLAG((tty), ECHOKE) |
| 182 | #define L_FLUSHO(tty) _L_FLAG((tty), FLUSHO) |
| 183 | #define L_PENDIN(tty) _L_FLAG((tty), PENDIN) |
| 184 | #define L_IEXTEN(tty) _L_FLAG((tty), IEXTEN) |
| 185 | #define L_EXTPROC(tty) _L_FLAG((tty), EXTPROC) |
| 186 | |
| 187 | struct device; |
| 188 | struct signal_struct; |
| 189 | |
| 190 | /* |
| 191 | * Port level information. Each device keeps its own port level information |
| 192 | * so provide a common structure for those ports wanting to use common support |
| 193 | * routines. |
| 194 | * |
| 195 | * The tty port has a different lifetime to the tty so must be kept apart. |
| 196 | * In addition be careful as tty -> port mappings are valid for the life |
| 197 | * of the tty object but in many cases port -> tty mappings are valid only |
| 198 | * until a hangup so don't use the wrong path. |
| 199 | */ |
| 200 | |
| 201 | struct tty_port; |
| 202 | |
| 203 | struct tty_port_operations { |
| 204 | /* Return 1 if the carrier is raised */ |
| 205 | int (*carrier_raised)(struct tty_port *port); |
| 206 | /* Control the DTR line */ |
| 207 | void (*dtr_rts)(struct tty_port *port, int raise); |
| 208 | /* Called when the last close completes or a hangup finishes |
| 209 | IFF the port was initialized. Do not use to free resources. Called |
| 210 | under the port mutex to serialize against activate/shutdowns */ |
| 211 | void (*shutdown)(struct tty_port *port); |
| 212 | /* Called under the port mutex from tty_port_open, serialized using |
| 213 | the port mutex */ |
| 214 | /* FIXME: long term getting the tty argument *out* of this would be |
| 215 | good for consoles */ |
| 216 | int (*activate)(struct tty_port *port, struct tty_struct *tty); |
| 217 | /* Called on the final put of a port */ |
| 218 | void (*destruct)(struct tty_port *port); |
| 219 | }; |
| 220 | |
| 221 | struct tty_port { |
| 222 | struct tty_bufhead buf; /* Locked internally */ |
| 223 | struct tty_struct *tty; /* Back pointer */ |
| 224 | struct tty_struct *itty; /* internal back ptr */ |
| 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 | low_latency:1; /* optional: tune for latency */ |
| 235 | struct mutex mutex; /* Locking */ |
| 236 | struct mutex buf_mutex; /* Buffer alloc lock */ |
| 237 | unsigned char *xmit_buf; /* Optional buffer */ |
| 238 | unsigned int close_delay; /* Close port delay */ |
| 239 | unsigned int closing_wait; /* Delay for output */ |
| 240 | int drain_delay; /* Set to zero if no pure time |
| 241 | based drain is needed else |
| 242 | set to size of fifo */ |
| 243 | struct kref kref; /* Ref counter */ |
| 244 | }; |
| 245 | |
| 246 | /* |
| 247 | * Where all of the state associated with a tty is kept while the tty |
| 248 | * is open. Since the termios state should be kept even if the tty |
| 249 | * has been closed --- for things like the baud rate, etc --- it is |
| 250 | * not stored here, but rather a pointer to the real state is stored |
| 251 | * here. Possible the winsize structure should have the same |
| 252 | * treatment, but (1) the default 80x24 is usually right and (2) it's |
| 253 | * most often used by a windowing system, which will set the correct |
| 254 | * size each time the window is created or resized anyway. |
| 255 | * - TYT, 9/14/92 |
| 256 | */ |
| 257 | |
| 258 | struct tty_operations; |
| 259 | |
| 260 | struct tty_struct { |
| 261 | int magic; |
| 262 | struct kref kref; |
| 263 | struct device *dev; |
| 264 | struct tty_driver *driver; |
| 265 | const struct tty_operations *ops; |
| 266 | int index; |
| 267 | |
| 268 | /* Protects ldisc changes: Lock tty not pty */ |
| 269 | struct ld_semaphore ldisc_sem; |
| 270 | struct tty_ldisc *ldisc; |
| 271 | |
| 272 | struct mutex atomic_write_lock; |
| 273 | struct mutex legacy_mutex; |
| 274 | struct mutex throttle_mutex; |
| 275 | struct rw_semaphore termios_rwsem; |
| 276 | struct mutex winsize_mutex; |
| 277 | spinlock_t ctrl_lock; |
| 278 | spinlock_t flow_lock; |
| 279 | /* Termios values are protected by the termios rwsem */ |
| 280 | struct ktermios termios, termios_locked; |
| 281 | struct termiox *termiox; /* May be NULL for unsupported */ |
| 282 | char name[64]; |
| 283 | struct pid *pgrp; /* Protected by ctrl lock */ |
| 284 | struct pid *session; |
| 285 | unsigned long flags; |
| 286 | int count; |
| 287 | struct winsize winsize; /* winsize_mutex */ |
| 288 | unsigned long stopped:1, /* flow_lock */ |
| 289 | flow_stopped:1, |
| 290 | unused:BITS_PER_LONG - 2; |
| 291 | int hw_stopped; |
| 292 | unsigned long ctrl_status:8, /* ctrl_lock */ |
| 293 | packet:1, |
| 294 | unused_ctrl:BITS_PER_LONG - 9; |
| 295 | unsigned int receive_room; /* Bytes free for queue */ |
| 296 | int flow_change; |
| 297 | |
| 298 | struct tty_struct *link; |
| 299 | struct fasync_struct *fasync; |
| 300 | int alt_speed; /* For magic substitution of 38400 bps */ |
| 301 | wait_queue_head_t write_wait; |
| 302 | wait_queue_head_t read_wait; |
| 303 | struct work_struct hangup_work; |
| 304 | void *disc_data; |
| 305 | void *driver_data; |
| 306 | struct list_head tty_files; |
| 307 | |
| 308 | #define N_TTY_BUF_SIZE 4096 |
| 309 | |
| 310 | int closing; |
| 311 | unsigned char *write_buf; |
| 312 | int write_cnt; |
| 313 | /* If the tty has a pending do_SAK, queue it here - akpm */ |
| 314 | struct work_struct SAK_work; |
| 315 | struct tty_port *port; |
| 316 | }; |
| 317 | |
| 318 | /* Each of a tty's open files has private_data pointing to tty_file_private */ |
| 319 | struct tty_file_private { |
| 320 | struct tty_struct *tty; |
| 321 | struct file *file; |
| 322 | struct list_head list; |
| 323 | }; |
| 324 | |
| 325 | /* tty magic number */ |
| 326 | #define TTY_MAGIC 0x5401 |
| 327 | |
| 328 | /* |
| 329 | * These bits are used in the flags field of the tty structure. |
| 330 | * |
| 331 | * So that interrupts won't be able to mess up the queues, |
| 332 | * copy_to_cooked must be atomic with respect to itself, as must |
| 333 | * tty->write. Thus, you must use the inline functions set_bit() and |
| 334 | * clear_bit() to make things atomic. |
| 335 | */ |
| 336 | #define TTY_THROTTLED 0 /* Call unthrottle() at threshold min */ |
| 337 | #define TTY_IO_ERROR 1 /* Cause an I/O error (may be no ldisc too) */ |
| 338 | #define TTY_OTHER_CLOSED 2 /* Other side (if any) has closed */ |
| 339 | #define TTY_EXCLUSIVE 3 /* Exclusive open mode */ |
| 340 | #define TTY_DEBUG 4 /* Debugging */ |
| 341 | #define TTY_DO_WRITE_WAKEUP 5 /* Call write_wakeup after queuing new */ |
| 342 | #define TTY_LDISC_OPEN 11 /* Line discipline is open */ |
| 343 | #define TTY_PTY_LOCK 16 /* pty private */ |
| 344 | #define TTY_NO_WRITE_SPLIT 17 /* Preserve write boundaries to driver */ |
| 345 | #define TTY_HUPPED 18 /* Post driver->hangup() */ |
| 346 | #define TTY_LDISC_HALTED 22 /* Line discipline is halted */ |
| 347 | |
| 348 | #define TTY_WRITE_FLUSH(tty) tty_write_flush((tty)) |
| 349 | |
| 350 | /* Values for tty->flow_change */ |
| 351 | #define TTY_THROTTLE_SAFE 1 |
| 352 | #define TTY_UNTHROTTLE_SAFE 2 |
| 353 | |
| 354 | static inline void __tty_set_flow_change(struct tty_struct *tty, int val) |
| 355 | { |
| 356 | tty->flow_change = val; |
| 357 | } |
| 358 | |
| 359 | static inline void tty_set_flow_change(struct tty_struct *tty, int val) |
| 360 | { |
| 361 | tty->flow_change = val; |
| 362 | smp_mb(); |
| 363 | } |
| 364 | |
| 365 | #ifdef CONFIG_TTY |
| 366 | extern void console_init(void); |
| 367 | extern void tty_kref_put(struct tty_struct *tty); |
| 368 | extern struct pid *tty_get_pgrp(struct tty_struct *tty); |
| 369 | extern void tty_vhangup_self(void); |
| 370 | extern void disassociate_ctty(int priv); |
| 371 | extern dev_t tty_devnum(struct tty_struct *tty); |
| 372 | extern void proc_clear_tty(struct task_struct *p); |
| 373 | extern struct tty_struct *get_current_tty(void); |
| 374 | /* tty_io.c */ |
| 375 | extern int __init tty_init(void); |
| 376 | #else |
| 377 | static inline void console_init(void) |
| 378 | { } |
| 379 | static inline void tty_kref_put(struct tty_struct *tty) |
| 380 | { } |
| 381 | static inline struct pid *tty_get_pgrp(struct tty_struct *tty) |
| 382 | { return NULL; } |
| 383 | static inline void tty_vhangup_self(void) |
| 384 | { } |
| 385 | static inline void disassociate_ctty(int priv) |
| 386 | { } |
| 387 | static inline dev_t tty_devnum(struct tty_struct *tty) |
| 388 | { return 0; } |
| 389 | static inline void proc_clear_tty(struct task_struct *p) |
| 390 | { } |
| 391 | static inline struct tty_struct *get_current_tty(void) |
| 392 | { return NULL; } |
| 393 | /* tty_io.c */ |
| 394 | static inline int __init tty_init(void) |
| 395 | { return 0; } |
| 396 | #endif |
| 397 | |
| 398 | extern void tty_write_flush(struct tty_struct *); |
| 399 | |
| 400 | extern struct ktermios tty_std_termios; |
| 401 | |
| 402 | extern int vcs_init(void); |
| 403 | |
| 404 | extern struct class *tty_class; |
| 405 | |
| 406 | /** |
| 407 | * tty_kref_get - get a tty reference |
| 408 | * @tty: tty device |
| 409 | * |
| 410 | * Return a new reference to a tty object. The caller must hold |
| 411 | * sufficient locks/counts to ensure that their existing reference cannot |
| 412 | * go away |
| 413 | */ |
| 414 | |
| 415 | static inline struct tty_struct *tty_kref_get(struct tty_struct *tty) |
| 416 | { |
| 417 | if (tty) |
| 418 | kref_get(&tty->kref); |
| 419 | return tty; |
| 420 | } |
| 421 | |
| 422 | extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode, |
| 423 | const char *routine); |
| 424 | extern char *tty_name(struct tty_struct *tty, char *buf); |
| 425 | extern void tty_wait_until_sent(struct tty_struct *tty, long timeout); |
| 426 | extern int tty_check_change(struct tty_struct *tty); |
| 427 | extern void __stop_tty(struct tty_struct *tty); |
| 428 | extern void stop_tty(struct tty_struct *tty); |
| 429 | extern void __start_tty(struct tty_struct *tty); |
| 430 | extern void start_tty(struct tty_struct *tty); |
| 431 | extern int tty_register_driver(struct tty_driver *driver); |
| 432 | extern int tty_unregister_driver(struct tty_driver *driver); |
| 433 | extern struct device *tty_register_device(struct tty_driver *driver, |
| 434 | unsigned index, struct device *dev); |
| 435 | extern struct device *tty_register_device_attr(struct tty_driver *driver, |
| 436 | unsigned index, struct device *device, |
| 437 | void *drvdata, |
| 438 | const struct attribute_group **attr_grp); |
| 439 | extern void tty_unregister_device(struct tty_driver *driver, unsigned index); |
| 440 | extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp, |
| 441 | int buflen); |
| 442 | extern void tty_write_message(struct tty_struct *tty, char *msg); |
| 443 | extern int tty_send_xchar(struct tty_struct *tty, char ch); |
| 444 | extern int tty_put_char(struct tty_struct *tty, unsigned char c); |
| 445 | extern int tty_chars_in_buffer(struct tty_struct *tty); |
| 446 | extern int tty_write_room(struct tty_struct *tty); |
| 447 | extern void tty_driver_flush_buffer(struct tty_struct *tty); |
| 448 | extern void tty_throttle(struct tty_struct *tty); |
| 449 | extern void tty_unthrottle(struct tty_struct *tty); |
| 450 | extern int tty_throttle_safe(struct tty_struct *tty); |
| 451 | extern int tty_unthrottle_safe(struct tty_struct *tty); |
| 452 | extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws); |
| 453 | extern void tty_driver_remove_tty(struct tty_driver *driver, |
| 454 | struct tty_struct *tty); |
| 455 | extern void tty_free_termios(struct tty_struct *tty); |
| 456 | extern int is_current_pgrp_orphaned(void); |
| 457 | extern int is_ignored(int sig); |
| 458 | extern int tty_signal(int sig, struct tty_struct *tty); |
| 459 | extern void tty_hangup(struct tty_struct *tty); |
| 460 | extern void tty_vhangup(struct tty_struct *tty); |
| 461 | extern int tty_hung_up_p(struct file *filp); |
| 462 | extern void do_SAK(struct tty_struct *tty); |
| 463 | extern void __do_SAK(struct tty_struct *tty); |
| 464 | extern void no_tty(void); |
| 465 | extern void tty_flush_to_ldisc(struct tty_struct *tty); |
| 466 | extern void tty_buffer_free_all(struct tty_port *port); |
| 467 | extern void tty_buffer_flush(struct tty_struct *tty, struct tty_ldisc *ld); |
| 468 | extern void tty_buffer_init(struct tty_port *port); |
| 469 | extern void tty_buffer_set_lock_subclass(struct tty_port *port); |
| 470 | extern speed_t tty_termios_baud_rate(struct ktermios *termios); |
| 471 | extern speed_t tty_termios_input_baud_rate(struct ktermios *termios); |
| 472 | extern void tty_termios_encode_baud_rate(struct ktermios *termios, |
| 473 | speed_t ibaud, speed_t obaud); |
| 474 | extern void tty_encode_baud_rate(struct tty_struct *tty, |
| 475 | speed_t ibaud, speed_t obaud); |
| 476 | |
| 477 | /** |
| 478 | * tty_get_baud_rate - get tty bit rates |
| 479 | * @tty: tty to query |
| 480 | * |
| 481 | * Returns the baud rate as an integer for this terminal. The |
| 482 | * termios lock must be held by the caller and the terminal bit |
| 483 | * flags may be updated. |
| 484 | * |
| 485 | * Locking: none |
| 486 | */ |
| 487 | static inline speed_t tty_get_baud_rate(struct tty_struct *tty) |
| 488 | { |
| 489 | return tty_termios_baud_rate(&tty->termios); |
| 490 | } |
| 491 | |
| 492 | extern void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old); |
| 493 | extern int tty_termios_hw_change(struct ktermios *a, struct ktermios *b); |
| 494 | extern int tty_set_termios(struct tty_struct *tty, struct ktermios *kt); |
| 495 | |
| 496 | extern struct tty_ldisc *tty_ldisc_ref(struct tty_struct *); |
| 497 | extern void tty_ldisc_deref(struct tty_ldisc *); |
| 498 | extern struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *); |
| 499 | extern void tty_ldisc_hangup(struct tty_struct *tty); |
| 500 | extern const struct file_operations tty_ldiscs_proc_fops; |
| 501 | |
| 502 | extern void tty_wakeup(struct tty_struct *tty); |
| 503 | extern void tty_ldisc_flush(struct tty_struct *tty); |
| 504 | |
| 505 | extern long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg); |
| 506 | extern int tty_mode_ioctl(struct tty_struct *tty, struct file *file, |
| 507 | unsigned int cmd, unsigned long arg); |
| 508 | extern int tty_perform_flush(struct tty_struct *tty, unsigned long arg); |
| 509 | extern void tty_default_fops(struct file_operations *fops); |
| 510 | extern struct tty_struct *alloc_tty_struct(struct tty_driver *driver, int idx); |
| 511 | extern int tty_alloc_file(struct file *file); |
| 512 | extern void tty_add_file(struct tty_struct *tty, struct file *file); |
| 513 | extern void tty_free_file(struct file *file); |
| 514 | extern void free_tty_struct(struct tty_struct *tty); |
| 515 | extern void deinitialize_tty_struct(struct tty_struct *tty); |
| 516 | extern struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx); |
| 517 | extern int tty_release(struct inode *inode, struct file *filp); |
| 518 | extern int tty_init_termios(struct tty_struct *tty); |
| 519 | extern int tty_standard_install(struct tty_driver *driver, |
| 520 | struct tty_struct *tty); |
| 521 | |
| 522 | extern struct mutex tty_mutex; |
| 523 | extern spinlock_t tty_files_lock; |
| 524 | |
| 525 | #define tty_is_writelocked(tty) (mutex_is_locked(&tty->atomic_write_lock)) |
| 526 | |
| 527 | extern void tty_port_init(struct tty_port *port); |
| 528 | extern void tty_port_link_device(struct tty_port *port, |
| 529 | struct tty_driver *driver, unsigned index); |
| 530 | extern struct device *tty_port_register_device(struct tty_port *port, |
| 531 | struct tty_driver *driver, unsigned index, |
| 532 | struct device *device); |
| 533 | extern struct device *tty_port_register_device_attr(struct tty_port *port, |
| 534 | struct tty_driver *driver, unsigned index, |
| 535 | struct device *device, void *drvdata, |
| 536 | const struct attribute_group **attr_grp); |
| 537 | extern int tty_port_alloc_xmit_buf(struct tty_port *port); |
| 538 | extern void tty_port_free_xmit_buf(struct tty_port *port); |
| 539 | extern void tty_port_destroy(struct tty_port *port); |
| 540 | extern void tty_port_put(struct tty_port *port); |
| 541 | |
| 542 | static inline struct tty_port *tty_port_get(struct tty_port *port) |
| 543 | { |
| 544 | if (port && kref_get_unless_zero(&port->kref)) |
| 545 | return port; |
| 546 | return NULL; |
| 547 | } |
| 548 | |
| 549 | /* If the cts flow control is enabled, return true. */ |
| 550 | static inline bool tty_port_cts_enabled(struct tty_port *port) |
| 551 | { |
| 552 | return port->flags & ASYNC_CTS_FLOW; |
| 553 | } |
| 554 | |
| 555 | extern struct tty_struct *tty_port_tty_get(struct tty_port *port); |
| 556 | extern void tty_port_tty_set(struct tty_port *port, struct tty_struct *tty); |
| 557 | extern int tty_port_carrier_raised(struct tty_port *port); |
| 558 | extern void tty_port_raise_dtr_rts(struct tty_port *port); |
| 559 | extern void tty_port_lower_dtr_rts(struct tty_port *port); |
| 560 | extern void tty_port_hangup(struct tty_port *port); |
| 561 | extern void tty_port_tty_hangup(struct tty_port *port, bool check_clocal); |
| 562 | extern void tty_port_tty_wakeup(struct tty_port *port); |
| 563 | extern int tty_port_block_til_ready(struct tty_port *port, |
| 564 | struct tty_struct *tty, struct file *filp); |
| 565 | extern int tty_port_close_start(struct tty_port *port, |
| 566 | struct tty_struct *tty, struct file *filp); |
| 567 | extern void tty_port_close_end(struct tty_port *port, struct tty_struct *tty); |
| 568 | extern void tty_port_close(struct tty_port *port, |
| 569 | struct tty_struct *tty, struct file *filp); |
| 570 | extern int tty_port_install(struct tty_port *port, struct tty_driver *driver, |
| 571 | struct tty_struct *tty); |
| 572 | extern int tty_port_open(struct tty_port *port, |
| 573 | struct tty_struct *tty, struct file *filp); |
| 574 | static inline int tty_port_users(struct tty_port *port) |
| 575 | { |
| 576 | return port->count + port->blocked_open; |
| 577 | } |
| 578 | |
| 579 | extern int tty_register_ldisc(int disc, struct tty_ldisc_ops *new_ldisc); |
| 580 | extern int tty_unregister_ldisc(int disc); |
| 581 | extern int tty_set_ldisc(struct tty_struct *tty, int ldisc); |
| 582 | extern int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty); |
| 583 | extern void tty_ldisc_release(struct tty_struct *tty); |
| 584 | extern void tty_ldisc_init(struct tty_struct *tty); |
| 585 | extern void tty_ldisc_deinit(struct tty_struct *tty); |
| 586 | extern void tty_ldisc_begin(void); |
| 587 | |
| 588 | static inline int tty_ldisc_receive_buf(struct tty_ldisc *ld, unsigned char *p, |
| 589 | char *f, int count) |
| 590 | { |
| 591 | if (ld->ops->receive_buf2) |
| 592 | count = ld->ops->receive_buf2(ld->tty, p, f, count); |
| 593 | else { |
| 594 | count = min_t(int, count, ld->tty->receive_room); |
| 595 | if (count) |
| 596 | ld->ops->receive_buf(ld->tty, p, f, count); |
| 597 | } |
| 598 | return count; |
| 599 | } |
| 600 | |
| 601 | |
| 602 | /* n_tty.c */ |
| 603 | extern struct tty_ldisc_ops tty_ldisc_N_TTY; |
| 604 | extern void n_tty_inherit_ops(struct tty_ldisc_ops *ops); |
| 605 | |
| 606 | /* tty_audit.c */ |
| 607 | #ifdef CONFIG_AUDIT |
| 608 | extern void tty_audit_add_data(struct tty_struct *tty, unsigned char *data, |
| 609 | size_t size, unsigned icanon); |
| 610 | extern void tty_audit_exit(void); |
| 611 | extern void tty_audit_fork(struct signal_struct *sig); |
| 612 | extern void tty_audit_tiocsti(struct tty_struct *tty, char ch); |
| 613 | extern void tty_audit_push(struct tty_struct *tty); |
| 614 | extern int tty_audit_push_current(void); |
| 615 | #else |
| 616 | static inline void tty_audit_add_data(struct tty_struct *tty, |
| 617 | unsigned char *data, size_t size, unsigned icanon) |
| 618 | { |
| 619 | } |
| 620 | static inline void tty_audit_tiocsti(struct tty_struct *tty, char ch) |
| 621 | { |
| 622 | } |
| 623 | static inline void tty_audit_exit(void) |
| 624 | { |
| 625 | } |
| 626 | static inline void tty_audit_fork(struct signal_struct *sig) |
| 627 | { |
| 628 | } |
| 629 | static inline void tty_audit_push(struct tty_struct *tty) |
| 630 | { |
| 631 | } |
| 632 | static inline int tty_audit_push_current(void) |
| 633 | { |
| 634 | return 0; |
| 635 | } |
| 636 | #endif |
| 637 | |
| 638 | /* tty_ioctl.c */ |
| 639 | extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, |
| 640 | unsigned int cmd, unsigned long arg); |
| 641 | extern long n_tty_compat_ioctl_helper(struct tty_struct *tty, struct file *file, |
| 642 | unsigned int cmd, unsigned long arg); |
| 643 | |
| 644 | /* vt.c */ |
| 645 | |
| 646 | extern int vt_ioctl(struct tty_struct *tty, |
| 647 | unsigned int cmd, unsigned long arg); |
| 648 | |
| 649 | extern long vt_compat_ioctl(struct tty_struct *tty, |
| 650 | unsigned int cmd, unsigned long arg); |
| 651 | |
| 652 | /* tty_mutex.c */ |
| 653 | /* functions for preparation of BKL removal */ |
| 654 | extern void __lockfunc tty_lock(struct tty_struct *tty); |
| 655 | extern void __lockfunc tty_unlock(struct tty_struct *tty); |
| 656 | extern void __lockfunc tty_lock_slave(struct tty_struct *tty); |
| 657 | extern void __lockfunc tty_unlock_slave(struct tty_struct *tty); |
| 658 | extern void tty_set_lock_subclass(struct tty_struct *tty); |
| 659 | /* |
| 660 | * this shall be called only from where BTM is held (like close) |
| 661 | * |
| 662 | * We need this to ensure nobody waits for us to finish while we are waiting. |
| 663 | * Without this we were encountering system stalls. |
| 664 | * |
| 665 | * This should be indeed removed with BTM removal later. |
| 666 | * |
| 667 | * Locking: BTM required. Nobody is allowed to hold port->mutex. |
| 668 | */ |
| 669 | static inline void tty_wait_until_sent_from_close(struct tty_struct *tty, |
| 670 | long timeout) |
| 671 | { |
| 672 | tty_unlock(tty); /* tty->ops->close holds the BTM, drop it while waiting */ |
| 673 | tty_wait_until_sent(tty, timeout); |
| 674 | tty_lock(tty); |
| 675 | } |
| 676 | |
| 677 | /* |
| 678 | * wait_event_interruptible_tty -- wait for a condition with the tty lock held |
| 679 | * |
| 680 | * The condition we are waiting for might take a long time to |
| 681 | * become true, or might depend on another thread taking the |
| 682 | * BTM. In either case, we need to drop the BTM to guarantee |
| 683 | * forward progress. This is a leftover from the conversion |
| 684 | * from the BKL and should eventually get removed as the BTM |
| 685 | * falls out of use. |
| 686 | * |
| 687 | * Do not use in new code. |
| 688 | */ |
| 689 | #define wait_event_interruptible_tty(tty, wq, condition) \ |
| 690 | ({ \ |
| 691 | int __ret = 0; \ |
| 692 | if (!(condition)) \ |
| 693 | __ret = __wait_event_interruptible_tty(tty, wq, \ |
| 694 | condition); \ |
| 695 | __ret; \ |
| 696 | }) |
| 697 | |
| 698 | #define __wait_event_interruptible_tty(tty, wq, condition) \ |
| 699 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
| 700 | tty_unlock(tty); \ |
| 701 | schedule(); \ |
| 702 | tty_lock(tty)) |
| 703 | |
| 704 | #ifdef CONFIG_PROC_FS |
| 705 | extern void proc_tty_register_driver(struct tty_driver *); |
| 706 | extern void proc_tty_unregister_driver(struct tty_driver *); |
| 707 | #else |
| 708 | static inline void proc_tty_register_driver(struct tty_driver *d) {} |
| 709 | static inline void proc_tty_unregister_driver(struct tty_driver *d) {} |
| 710 | #endif |
| 711 | |
| 712 | #endif |