2 * Copyright (C) 1991, 1992 Linus Torvalds
6 * 'tty_io.c' gives an orthogonal feeling to tty's, be they consoles
7 * or rs-channels. It also implements echoing, cooked mode etc.
9 * Kill-line thanks to John T Kohl, who also corrected VMIN = VTIME = 0.
11 * Modified by Theodore Ts'o, 9/14/92, to dynamically allocate the
12 * tty_struct and tty_queue structures. Previously there was an array
13 * of 256 tty_struct's which was statically allocated, and the
14 * tty_queue structures were allocated at boot time. Both are now
15 * dynamically allocated only when the tty is open.
17 * Also restructured routines so that there is more of a separation
18 * between the high-level tty routines (tty_io.c and tty_ioctl.c) and
19 * the low-level tty routines (serial.c, pty.c, console.c). This
20 * makes for cleaner and more compact code. -TYT, 9/17/92
22 * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
23 * which can be dynamically activated and de-activated by the line
24 * discipline handling modules (like SLIP).
26 * NOTE: pay no attention to the line discipline code (yet); its
27 * interface is still subject to change in this version...
30 * Added functionality to the OPOST tty handling. No delays, but all
31 * other bits should be there.
32 * -- Nick Holloway <alfie@dcs.warwick.ac.uk>, 27th May 1993.
34 * Rewrote canonical mode and added more termios flags.
35 * -- julian@uhunix.uhcc.hawaii.edu (J. Cowley), 13Jan94
37 * Reorganized FASYNC support so mouse code can share it.
38 * -- ctm@ardi.com, 9Sep95
40 * New TIOCLINUX variants added.
41 * -- mj@k332.feld.cvut.cz, 19-Nov-95
43 * Restrict vt switching via ioctl()
44 * -- grif@cs.ucr.edu, 5-Dec-95
46 * Move console and virtual terminal code to more appropriate files,
47 * implement CONFIG_VT and generalize console device interface.
48 * -- Marko Kohtala <Marko.Kohtala@hut.fi>, March 97
50 * Rewrote tty_init_dev and tty_release_dev to eliminate races.
51 * -- Bill Hawes <whawes@star.net>, June 97
53 * Added devfs support.
54 * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 13-Jan-1998
56 * Added support for a Unix98-style ptmx device.
57 * -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
59 * Reduced memory usage for older ARM systems
60 * -- Russell King <rmk@arm.linux.org.uk>
62 * Move do_SAK() into process context. Less stack use in devfs functions.
63 * alloc_tty_struct() always uses kmalloc()
64 * -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01
67 #include <linux/types.h>
68 #include <linux/major.h>
69 #include <linux/errno.h>
70 #include <linux/signal.h>
71 #include <linux/fcntl.h>
72 #include <linux/sched.h>
73 #include <linux/interrupt.h>
74 #include <linux/tty.h>
75 #include <linux/tty_driver.h>
76 #include <linux/tty_flip.h>
77 #include <linux/devpts_fs.h>
78 #include <linux/file.h>
79 #include <linux/fdtable.h>
80 #include <linux/console.h>
81 #include <linux/timer.h>
82 #include <linux/ctype.h>
85 #include <linux/string.h>
86 #include <linux/slab.h>
87 #include <linux/poll.h>
88 #include <linux/proc_fs.h>
89 #include <linux/init.h>
90 #include <linux/module.h>
91 #include <linux/device.h>
92 #include <linux/wait.h>
93 #include <linux/bitops.h>
94 #include <linux/delay.h>
95 #include <linux/seq_file.h>
96 #include <linux/serial.h>
97 #include <linux/ratelimit.h>
99 #include <linux/uaccess.h>
101 #include <linux/kbd_kern.h>
102 #include <linux/vt_kern.h>
103 #include <linux/selection.h>
105 #include <linux/kmod.h>
106 #include <linux/nsproxy.h>
108 #undef TTY_DEBUG_HANGUP
109 #ifdef TTY_DEBUG_HANGUP
110 # define tty_debug_hangup(tty, f, args...) tty_debug(tty, f, ##args)
112 # define tty_debug_hangup(tty, f, args...) do { } while (0)
115 #define TTY_PARANOIA_CHECK 1
116 #define CHECK_TTY_COUNT 1
118 struct ktermios tty_std_termios
= { /* for the benefit of tty drivers */
119 .c_iflag
= ICRNL
| IXON
,
120 .c_oflag
= OPOST
| ONLCR
,
121 .c_cflag
= B38400
| CS8
| CREAD
| HUPCL
,
122 .c_lflag
= ISIG
| ICANON
| ECHO
| ECHOE
| ECHOK
|
123 ECHOCTL
| ECHOKE
| IEXTEN
,
129 EXPORT_SYMBOL(tty_std_termios
);
131 /* This list gets poked at by procfs and various bits of boot up code. This
132 could do with some rationalisation such as pulling the tty proc function
135 LIST_HEAD(tty_drivers
); /* linked list of tty drivers */
137 /* Mutex to protect creating and releasing a tty. This is shared with
138 vt.c for deeply disgusting hack reasons */
139 DEFINE_MUTEX(tty_mutex
);
140 EXPORT_SYMBOL(tty_mutex
);
142 /* Spinlock to protect the tty->tty_files list */
143 DEFINE_SPINLOCK(tty_files_lock
);
145 static ssize_t
tty_read(struct file
*, char __user
*, size_t, loff_t
*);
146 static ssize_t
tty_write(struct file
*, const char __user
*, size_t, loff_t
*);
147 ssize_t
redirected_tty_write(struct file
*, const char __user
*,
149 static unsigned int tty_poll(struct file
*, poll_table
*);
150 static int tty_open(struct inode
*, struct file
*);
151 long tty_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
);
153 static long tty_compat_ioctl(struct file
*file
, unsigned int cmd
,
156 #define tty_compat_ioctl NULL
158 static int __tty_fasync(int fd
, struct file
*filp
, int on
);
159 static int tty_fasync(int fd
, struct file
*filp
, int on
);
160 static void release_tty(struct tty_struct
*tty
, int idx
);
163 * free_tty_struct - free a disused tty
164 * @tty: tty struct to free
166 * Free the write buffers, tty queue and tty memory itself.
168 * Locking: none. Must be called after tty is definitely unused
171 void free_tty_struct(struct tty_struct
*tty
)
175 put_device(tty
->dev
);
176 kfree(tty
->write_buf
);
177 tty
->magic
= 0xDEADDEAD;
181 static inline struct tty_struct
*file_tty(struct file
*file
)
183 return ((struct tty_file_private
*)file
->private_data
)->tty
;
186 int tty_alloc_file(struct file
*file
)
188 struct tty_file_private
*priv
;
190 priv
= kmalloc(sizeof(*priv
), GFP_KERNEL
);
194 file
->private_data
= priv
;
199 /* Associate a new file with the tty structure */
200 void tty_add_file(struct tty_struct
*tty
, struct file
*file
)
202 struct tty_file_private
*priv
= file
->private_data
;
207 spin_lock(&tty_files_lock
);
208 list_add(&priv
->list
, &tty
->tty_files
);
209 spin_unlock(&tty_files_lock
);
213 * tty_free_file - free file->private_data
215 * This shall be used only for fail path handling when tty_add_file was not
218 void tty_free_file(struct file
*file
)
220 struct tty_file_private
*priv
= file
->private_data
;
222 file
->private_data
= NULL
;
226 /* Delete file from its tty */
227 static void tty_del_file(struct file
*file
)
229 struct tty_file_private
*priv
= file
->private_data
;
231 spin_lock(&tty_files_lock
);
232 list_del(&priv
->list
);
233 spin_unlock(&tty_files_lock
);
238 #define TTY_NUMBER(tty) ((tty)->index + (tty)->driver->name_base)
241 * tty_name - return tty naming
242 * @tty: tty structure
244 * Convert a tty structure into a name. The name reflects the kernel
245 * naming policy and if udev is in use may not reflect user space
250 const char *tty_name(const struct tty_struct
*tty
)
252 if (!tty
) /* Hmm. NULL pointer. That's fun. */
257 EXPORT_SYMBOL(tty_name
);
259 const char *tty_driver_name(const struct tty_struct
*tty
)
261 if (!tty
|| !tty
->driver
)
263 return tty
->driver
->name
;
266 static int tty_paranoia_check(struct tty_struct
*tty
, struct inode
*inode
,
269 #ifdef TTY_PARANOIA_CHECK
272 "null TTY for (%d:%d) in %s\n",
273 imajor(inode
), iminor(inode
), routine
);
276 if (tty
->magic
!= TTY_MAGIC
) {
278 "bad magic number for tty struct (%d:%d) in %s\n",
279 imajor(inode
), iminor(inode
), routine
);
286 /* Caller must hold tty_lock */
287 static int check_tty_count(struct tty_struct
*tty
, const char *routine
)
289 #ifdef CHECK_TTY_COUNT
293 spin_lock(&tty_files_lock
);
294 list_for_each(p
, &tty
->tty_files
) {
297 spin_unlock(&tty_files_lock
);
298 if (tty
->driver
->type
== TTY_DRIVER_TYPE_PTY
&&
299 tty
->driver
->subtype
== PTY_TYPE_SLAVE
&&
300 tty
->link
&& tty
->link
->count
)
302 if (tty
->count
!= count
) {
303 tty_warn(tty
, "%s: tty->count(%d) != #fd's(%d)\n",
304 routine
, tty
->count
, count
);
312 * get_tty_driver - find device of a tty
313 * @dev_t: device identifier
314 * @index: returns the index of the tty
316 * This routine returns a tty driver structure, given a device number
317 * and also passes back the index number.
319 * Locking: caller must hold tty_mutex
322 static struct tty_driver
*get_tty_driver(dev_t device
, int *index
)
324 struct tty_driver
*p
;
326 list_for_each_entry(p
, &tty_drivers
, tty_drivers
) {
327 dev_t base
= MKDEV(p
->major
, p
->minor_start
);
328 if (device
< base
|| device
>= base
+ p
->num
)
330 *index
= device
- base
;
331 return tty_driver_kref_get(p
);
336 #ifdef CONFIG_CONSOLE_POLL
339 * tty_find_polling_driver - find device of a polled tty
340 * @name: name string to match
341 * @line: pointer to resulting tty line nr
343 * This routine returns a tty driver structure, given a name
344 * and the condition that the tty driver is capable of polled
347 struct tty_driver
*tty_find_polling_driver(char *name
, int *line
)
349 struct tty_driver
*p
, *res
= NULL
;
354 for (str
= name
; *str
; str
++)
355 if ((*str
>= '0' && *str
<= '9') || *str
== ',')
361 tty_line
= simple_strtoul(str
, &str
, 10);
363 mutex_lock(&tty_mutex
);
364 /* Search through the tty devices to look for a match */
365 list_for_each_entry(p
, &tty_drivers
, tty_drivers
) {
366 if (strncmp(name
, p
->name
, len
) != 0)
374 if (tty_line
>= 0 && tty_line
< p
->num
&& p
->ops
&&
375 p
->ops
->poll_init
&& !p
->ops
->poll_init(p
, tty_line
, stp
)) {
376 res
= tty_driver_kref_get(p
);
381 mutex_unlock(&tty_mutex
);
385 EXPORT_SYMBOL_GPL(tty_find_polling_driver
);
389 * tty_check_change - check for POSIX terminal changes
392 * If we try to write to, or set the state of, a terminal and we're
393 * not in the foreground, send a SIGTTOU. If the signal is blocked or
394 * ignored, go ahead and perform the operation. (POSIX 7.2)
399 int __tty_check_change(struct tty_struct
*tty
, int sig
)
402 struct pid
*pgrp
, *tty_pgrp
;
405 if (current
->signal
->tty
!= tty
)
409 pgrp
= task_pgrp(current
);
411 spin_lock_irqsave(&tty
->ctrl_lock
, flags
);
412 tty_pgrp
= tty
->pgrp
;
413 spin_unlock_irqrestore(&tty
->ctrl_lock
, flags
);
415 if (tty_pgrp
&& pgrp
!= tty
->pgrp
) {
416 if (is_ignored(sig
)) {
419 } else if (is_current_pgrp_orphaned())
422 kill_pgrp(pgrp
, sig
, 1);
423 set_thread_flag(TIF_SIGPENDING
);
430 tty_warn(tty
, "sig=%d, tty->pgrp == NULL!\n", sig
);
435 int tty_check_change(struct tty_struct
*tty
)
437 return __tty_check_change(tty
, SIGTTOU
);
439 EXPORT_SYMBOL(tty_check_change
);
441 static ssize_t
hung_up_tty_read(struct file
*file
, char __user
*buf
,
442 size_t count
, loff_t
*ppos
)
447 static ssize_t
hung_up_tty_write(struct file
*file
, const char __user
*buf
,
448 size_t count
, loff_t
*ppos
)
453 /* No kernel lock held - none needed ;) */
454 static unsigned int hung_up_tty_poll(struct file
*filp
, poll_table
*wait
)
456 return POLLIN
| POLLOUT
| POLLERR
| POLLHUP
| POLLRDNORM
| POLLWRNORM
;
459 static long hung_up_tty_ioctl(struct file
*file
, unsigned int cmd
,
462 return cmd
== TIOCSPGRP
? -ENOTTY
: -EIO
;
465 static long hung_up_tty_compat_ioctl(struct file
*file
,
466 unsigned int cmd
, unsigned long arg
)
468 return cmd
== TIOCSPGRP
? -ENOTTY
: -EIO
;
471 static const struct file_operations tty_fops
= {
476 .unlocked_ioctl
= tty_ioctl
,
477 .compat_ioctl
= tty_compat_ioctl
,
479 .release
= tty_release
,
480 .fasync
= tty_fasync
,
483 static const struct file_operations console_fops
= {
486 .write
= redirected_tty_write
,
488 .unlocked_ioctl
= tty_ioctl
,
489 .compat_ioctl
= tty_compat_ioctl
,
491 .release
= tty_release
,
492 .fasync
= tty_fasync
,
495 static const struct file_operations hung_up_tty_fops
= {
497 .read
= hung_up_tty_read
,
498 .write
= hung_up_tty_write
,
499 .poll
= hung_up_tty_poll
,
500 .unlocked_ioctl
= hung_up_tty_ioctl
,
501 .compat_ioctl
= hung_up_tty_compat_ioctl
,
502 .release
= tty_release
,
505 static DEFINE_SPINLOCK(redirect_lock
);
506 static struct file
*redirect
;
509 void proc_clear_tty(struct task_struct
*p
)
512 struct tty_struct
*tty
;
513 spin_lock_irqsave(&p
->sighand
->siglock
, flags
);
514 tty
= p
->signal
->tty
;
515 p
->signal
->tty
= NULL
;
516 spin_unlock_irqrestore(&p
->sighand
->siglock
, flags
);
521 * proc_set_tty - set the controlling terminal
523 * Only callable by the session leader and only if it does not already have
524 * a controlling terminal.
526 * Caller must hold: tty_lock()
527 * a readlock on tasklist_lock
530 static void __proc_set_tty(struct tty_struct
*tty
)
534 spin_lock_irqsave(&tty
->ctrl_lock
, flags
);
536 * The session and fg pgrp references will be non-NULL if
537 * tiocsctty() is stealing the controlling tty
539 put_pid(tty
->session
);
541 tty
->pgrp
= get_pid(task_pgrp(current
));
542 spin_unlock_irqrestore(&tty
->ctrl_lock
, flags
);
543 tty
->session
= get_pid(task_session(current
));
544 if (current
->signal
->tty
) {
545 tty_debug(tty
, "current tty %s not NULL!!\n",
546 current
->signal
->tty
->name
);
547 tty_kref_put(current
->signal
->tty
);
549 put_pid(current
->signal
->tty_old_pgrp
);
550 current
->signal
->tty
= tty_kref_get(tty
);
551 current
->signal
->tty_old_pgrp
= NULL
;
554 static void proc_set_tty(struct tty_struct
*tty
)
556 spin_lock_irq(¤t
->sighand
->siglock
);
558 spin_unlock_irq(¤t
->sighand
->siglock
);
561 struct tty_struct
*get_current_tty(void)
563 struct tty_struct
*tty
;
566 spin_lock_irqsave(¤t
->sighand
->siglock
, flags
);
567 tty
= tty_kref_get(current
->signal
->tty
);
568 spin_unlock_irqrestore(¤t
->sighand
->siglock
, flags
);
571 EXPORT_SYMBOL_GPL(get_current_tty
);
573 static void session_clear_tty(struct pid
*session
)
575 struct task_struct
*p
;
576 do_each_pid_task(session
, PIDTYPE_SID
, p
) {
578 } while_each_pid_task(session
, PIDTYPE_SID
, p
);
582 * tty_wakeup - request more data
585 * Internal and external helper for wakeups of tty. This function
586 * informs the line discipline if present that the driver is ready
587 * to receive more output data.
590 void tty_wakeup(struct tty_struct
*tty
)
592 struct tty_ldisc
*ld
;
594 if (test_bit(TTY_DO_WRITE_WAKEUP
, &tty
->flags
)) {
595 ld
= tty_ldisc_ref(tty
);
597 if (ld
->ops
->write_wakeup
)
598 ld
->ops
->write_wakeup(tty
);
602 wake_up_interruptible_poll(&tty
->write_wait
, POLLOUT
);
605 EXPORT_SYMBOL_GPL(tty_wakeup
);
608 * tty_signal_session_leader - sends SIGHUP to session leader
609 * @tty controlling tty
610 * @exit_session if non-zero, signal all foreground group processes
612 * Send SIGHUP and SIGCONT to the session leader and its process group.
613 * Optionally, signal all processes in the foreground process group.
615 * Returns the number of processes in the session with this tty
616 * as their controlling terminal. This value is used to drop
617 * tty references for those processes.
619 static int tty_signal_session_leader(struct tty_struct
*tty
, int exit_session
)
621 struct task_struct
*p
;
623 struct pid
*tty_pgrp
= NULL
;
625 read_lock(&tasklist_lock
);
627 do_each_pid_task(tty
->session
, PIDTYPE_SID
, p
) {
628 spin_lock_irq(&p
->sighand
->siglock
);
629 if (p
->signal
->tty
== tty
) {
630 p
->signal
->tty
= NULL
;
631 /* We defer the dereferences outside fo
635 if (!p
->signal
->leader
) {
636 spin_unlock_irq(&p
->sighand
->siglock
);
639 __group_send_sig_info(SIGHUP
, SEND_SIG_PRIV
, p
);
640 __group_send_sig_info(SIGCONT
, SEND_SIG_PRIV
, p
);
641 put_pid(p
->signal
->tty_old_pgrp
); /* A noop */
642 spin_lock(&tty
->ctrl_lock
);
643 tty_pgrp
= get_pid(tty
->pgrp
);
645 p
->signal
->tty_old_pgrp
= get_pid(tty
->pgrp
);
646 spin_unlock(&tty
->ctrl_lock
);
647 spin_unlock_irq(&p
->sighand
->siglock
);
648 } while_each_pid_task(tty
->session
, PIDTYPE_SID
, p
);
650 read_unlock(&tasklist_lock
);
654 kill_pgrp(tty_pgrp
, SIGHUP
, exit_session
);
662 * __tty_hangup - actual handler for hangup events
665 * This can be called by a "kworker" kernel thread. That is process
666 * synchronous but doesn't hold any locks, so we need to make sure we
667 * have the appropriate locks for what we're doing.
669 * The hangup event clears any pending redirections onto the hung up
670 * device. It ensures future writes will error and it does the needed
671 * line discipline hangup and signal delivery. The tty object itself
676 * redirect lock for undoing redirection
677 * file list lock for manipulating list of ttys
678 * tty_ldiscs_lock from called functions
679 * termios_rwsem resetting termios data
680 * tasklist_lock to walk task list for hangup event
681 * ->siglock to protect ->signal/->sighand
683 static void __tty_hangup(struct tty_struct
*tty
, int exit_session
)
685 struct file
*cons_filp
= NULL
;
686 struct file
*filp
, *f
= NULL
;
687 struct tty_file_private
*priv
;
688 int closecount
= 0, n
;
695 spin_lock(&redirect_lock
);
696 if (redirect
&& file_tty(redirect
) == tty
) {
700 spin_unlock(&redirect_lock
);
704 if (test_bit(TTY_HUPPED
, &tty
->flags
)) {
709 /* inuse_filps is protected by the single tty lock,
710 this really needs to change if we want to flush the
711 workqueue with the lock held */
712 check_tty_count(tty
, "tty_hangup");
714 spin_lock(&tty_files_lock
);
715 /* This breaks for file handles being sent over AF_UNIX sockets ? */
716 list_for_each_entry(priv
, &tty
->tty_files
, list
) {
718 if (filp
->f_op
->write
== redirected_tty_write
)
720 if (filp
->f_op
->write
!= tty_write
)
723 __tty_fasync(-1, filp
, 0); /* can't block */
724 filp
->f_op
= &hung_up_tty_fops
;
726 spin_unlock(&tty_files_lock
);
728 refs
= tty_signal_session_leader(tty
, exit_session
);
729 /* Account for the p->signal references we killed */
733 tty_ldisc_hangup(tty
);
735 spin_lock_irq(&tty
->ctrl_lock
);
736 clear_bit(TTY_THROTTLED
, &tty
->flags
);
737 clear_bit(TTY_DO_WRITE_WAKEUP
, &tty
->flags
);
738 put_pid(tty
->session
);
742 tty
->ctrl_status
= 0;
743 spin_unlock_irq(&tty
->ctrl_lock
);
746 * If one of the devices matches a console pointer, we
747 * cannot just call hangup() because that will cause
748 * tty->count and state->count to go out of sync.
749 * So we just call close() the right number of times.
753 for (n
= 0; n
< closecount
; n
++)
754 tty
->ops
->close(tty
, cons_filp
);
755 } else if (tty
->ops
->hangup
)
756 tty
->ops
->hangup(tty
);
758 * We don't want to have driver/ldisc interactions beyond
759 * the ones we did here. The driver layer expects no
760 * calls after ->hangup() from the ldisc side. However we
761 * can't yet guarantee all that.
763 set_bit(TTY_HUPPED
, &tty
->flags
);
770 static void do_tty_hangup(struct work_struct
*work
)
772 struct tty_struct
*tty
=
773 container_of(work
, struct tty_struct
, hangup_work
);
775 __tty_hangup(tty
, 0);
779 * tty_hangup - trigger a hangup event
780 * @tty: tty to hangup
782 * A carrier loss (virtual or otherwise) has occurred on this like
783 * schedule a hangup sequence to run after this event.
786 void tty_hangup(struct tty_struct
*tty
)
788 tty_debug_hangup(tty
, "\n");
789 schedule_work(&tty
->hangup_work
);
792 EXPORT_SYMBOL(tty_hangup
);
795 * tty_vhangup - process vhangup
796 * @tty: tty to hangup
798 * The user has asked via system call for the terminal to be hung up.
799 * We do this synchronously so that when the syscall returns the process
800 * is complete. That guarantee is necessary for security reasons.
803 void tty_vhangup(struct tty_struct
*tty
)
805 tty_debug_hangup(tty
, "\n");
806 __tty_hangup(tty
, 0);
809 EXPORT_SYMBOL(tty_vhangup
);
813 * tty_vhangup_self - process vhangup for own ctty
815 * Perform a vhangup on the current controlling tty
818 void tty_vhangup_self(void)
820 struct tty_struct
*tty
;
822 tty
= get_current_tty();
830 * tty_vhangup_session - hangup session leader exit
831 * @tty: tty to hangup
833 * The session leader is exiting and hanging up its controlling terminal.
834 * Every process in the foreground process group is signalled SIGHUP.
836 * We do this synchronously so that when the syscall returns the process
837 * is complete. That guarantee is necessary for security reasons.
840 static void tty_vhangup_session(struct tty_struct
*tty
)
842 tty_debug_hangup(tty
, "\n");
843 __tty_hangup(tty
, 1);
847 * tty_hung_up_p - was tty hung up
848 * @filp: file pointer of tty
850 * Return true if the tty has been subject to a vhangup or a carrier
854 int tty_hung_up_p(struct file
*filp
)
856 return (filp
->f_op
== &hung_up_tty_fops
);
859 EXPORT_SYMBOL(tty_hung_up_p
);
862 * disassociate_ctty - disconnect controlling tty
863 * @on_exit: true if exiting so need to "hang up" the session
865 * This function is typically called only by the session leader, when
866 * it wants to disassociate itself from its controlling tty.
868 * It performs the following functions:
869 * (1) Sends a SIGHUP and SIGCONT to the foreground process group
870 * (2) Clears the tty from being controlling the session
871 * (3) Clears the controlling tty for all processes in the
874 * The argument on_exit is set to 1 if called when a process is
875 * exiting; it is 0 if called by the ioctl TIOCNOTTY.
878 * BTM is taken for hysterical raisins, and held when
879 * called from no_tty().
880 * tty_mutex is taken to protect tty
881 * ->siglock is taken to protect ->signal/->sighand
882 * tasklist_lock is taken to walk process list for sessions
883 * ->siglock is taken to protect ->signal/->sighand
886 void disassociate_ctty(int on_exit
)
888 struct tty_struct
*tty
;
890 if (!current
->signal
->leader
)
893 tty
= get_current_tty();
895 if (on_exit
&& tty
->driver
->type
!= TTY_DRIVER_TYPE_PTY
) {
896 tty_vhangup_session(tty
);
898 struct pid
*tty_pgrp
= tty_get_pgrp(tty
);
900 kill_pgrp(tty_pgrp
, SIGHUP
, on_exit
);
902 kill_pgrp(tty_pgrp
, SIGCONT
, on_exit
);
908 } else if (on_exit
) {
909 struct pid
*old_pgrp
;
910 spin_lock_irq(¤t
->sighand
->siglock
);
911 old_pgrp
= current
->signal
->tty_old_pgrp
;
912 current
->signal
->tty_old_pgrp
= NULL
;
913 spin_unlock_irq(¤t
->sighand
->siglock
);
915 kill_pgrp(old_pgrp
, SIGHUP
, on_exit
);
916 kill_pgrp(old_pgrp
, SIGCONT
, on_exit
);
922 spin_lock_irq(¤t
->sighand
->siglock
);
923 put_pid(current
->signal
->tty_old_pgrp
);
924 current
->signal
->tty_old_pgrp
= NULL
;
926 tty
= tty_kref_get(current
->signal
->tty
);
929 spin_lock_irqsave(&tty
->ctrl_lock
, flags
);
930 put_pid(tty
->session
);
934 spin_unlock_irqrestore(&tty
->ctrl_lock
, flags
);
937 tty_debug_hangup(tty
, "no current tty\n");
939 spin_unlock_irq(¤t
->sighand
->siglock
);
940 /* Now clear signal->tty under the lock */
941 read_lock(&tasklist_lock
);
942 session_clear_tty(task_session(current
));
943 read_unlock(&tasklist_lock
);
948 * no_tty - Ensure the current process does not have a controlling tty
952 /* FIXME: Review locking here. The tty_lock never covered any race
953 between a new association and proc_clear_tty but possible we need
954 to protect against this anyway */
955 struct task_struct
*tsk
= current
;
956 disassociate_ctty(0);
962 * stop_tty - propagate flow control
965 * Perform flow control to the driver. May be called
966 * on an already stopped device and will not re-call the driver
969 * This functionality is used by both the line disciplines for
970 * halting incoming flow and by the driver. It may therefore be
971 * called from any context, may be under the tty atomic_write_lock
978 void __stop_tty(struct tty_struct
*tty
)
987 void stop_tty(struct tty_struct
*tty
)
991 spin_lock_irqsave(&tty
->flow_lock
, flags
);
993 spin_unlock_irqrestore(&tty
->flow_lock
, flags
);
995 EXPORT_SYMBOL(stop_tty
);
998 * start_tty - propagate flow control
1001 * Start a tty that has been stopped if at all possible. If this
1002 * tty was previous stopped and is now being started, the driver
1003 * start method is invoked and the line discipline woken.
1009 void __start_tty(struct tty_struct
*tty
)
1011 if (!tty
->stopped
|| tty
->flow_stopped
)
1014 if (tty
->ops
->start
)
1015 tty
->ops
->start(tty
);
1019 void start_tty(struct tty_struct
*tty
)
1021 unsigned long flags
;
1023 spin_lock_irqsave(&tty
->flow_lock
, flags
);
1025 spin_unlock_irqrestore(&tty
->flow_lock
, flags
);
1027 EXPORT_SYMBOL(start_tty
);
1029 static void tty_update_time(struct timespec
*time
)
1031 unsigned long sec
= get_seconds();
1034 * We only care if the two values differ in anything other than the
1035 * lower three bits (i.e every 8 seconds). If so, then we can update
1036 * the time of the tty device, otherwise it could be construded as a
1037 * security leak to let userspace know the exact timing of the tty.
1039 if ((sec
^ time
->tv_sec
) & ~7)
1044 * tty_read - read method for tty device files
1045 * @file: pointer to tty file
1047 * @count: size of user buffer
1050 * Perform the read system call function on this terminal device. Checks
1051 * for hung up devices before calling the line discipline method.
1054 * Locks the line discipline internally while needed. Multiple
1055 * read calls may be outstanding in parallel.
1058 static ssize_t
tty_read(struct file
*file
, char __user
*buf
, size_t count
,
1062 struct inode
*inode
= file_inode(file
);
1063 struct tty_struct
*tty
= file_tty(file
);
1064 struct tty_ldisc
*ld
;
1066 if (tty_paranoia_check(tty
, inode
, "tty_read"))
1068 if (!tty
|| (test_bit(TTY_IO_ERROR
, &tty
->flags
)))
1071 /* We want to wait for the line discipline to sort out in this
1073 ld
= tty_ldisc_ref_wait(tty
);
1075 i
= ld
->ops
->read(tty
, file
, buf
, count
);
1078 tty_ldisc_deref(ld
);
1081 tty_update_time(&inode
->i_atime
);
1086 static void tty_write_unlock(struct tty_struct
*tty
)
1088 mutex_unlock(&tty
->atomic_write_lock
);
1089 wake_up_interruptible_poll(&tty
->write_wait
, POLLOUT
);
1092 static int tty_write_lock(struct tty_struct
*tty
, int ndelay
)
1094 if (!mutex_trylock(&tty
->atomic_write_lock
)) {
1097 if (mutex_lock_interruptible(&tty
->atomic_write_lock
))
1098 return -ERESTARTSYS
;
1104 * Split writes up in sane blocksizes to avoid
1105 * denial-of-service type attacks
1107 static inline ssize_t
do_tty_write(
1108 ssize_t (*write
)(struct tty_struct
*, struct file
*, const unsigned char *, size_t),
1109 struct tty_struct
*tty
,
1111 const char __user
*buf
,
1114 ssize_t ret
, written
= 0;
1117 ret
= tty_write_lock(tty
, file
->f_flags
& O_NDELAY
);
1122 * We chunk up writes into a temporary buffer. This
1123 * simplifies low-level drivers immensely, since they
1124 * don't have locking issues and user mode accesses.
1126 * But if TTY_NO_WRITE_SPLIT is set, we should use a
1129 * The default chunk-size is 2kB, because the NTTY
1130 * layer has problems with bigger chunks. It will
1131 * claim to be able to handle more characters than
1134 * FIXME: This can probably go away now except that 64K chunks
1135 * are too likely to fail unless switched to vmalloc...
1138 if (test_bit(TTY_NO_WRITE_SPLIT
, &tty
->flags
))
1143 /* write_buf/write_cnt is protected by the atomic_write_lock mutex */
1144 if (tty
->write_cnt
< chunk
) {
1145 unsigned char *buf_chunk
;
1150 buf_chunk
= kmalloc(chunk
, GFP_KERNEL
);
1155 kfree(tty
->write_buf
);
1156 tty
->write_cnt
= chunk
;
1157 tty
->write_buf
= buf_chunk
;
1160 /* Do the write .. */
1162 size_t size
= count
;
1166 if (copy_from_user(tty
->write_buf
, buf
, size
))
1168 ret
= write(tty
, file
, tty
->write_buf
, size
);
1177 if (signal_pending(current
))
1182 tty_update_time(&file_inode(file
)->i_mtime
);
1186 tty_write_unlock(tty
);
1191 * tty_write_message - write a message to a certain tty, not just the console.
1192 * @tty: the destination tty_struct
1193 * @msg: the message to write
1195 * This is used for messages that need to be redirected to a specific tty.
1196 * We don't put it into the syslog queue right now maybe in the future if
1199 * We must still hold the BTM and test the CLOSING flag for the moment.
1202 void tty_write_message(struct tty_struct
*tty
, char *msg
)
1205 mutex_lock(&tty
->atomic_write_lock
);
1207 if (tty
->ops
->write
&& tty
->count
> 0)
1208 tty
->ops
->write(tty
, msg
, strlen(msg
));
1210 tty_write_unlock(tty
);
1217 * tty_write - write method for tty device file
1218 * @file: tty file pointer
1219 * @buf: user data to write
1220 * @count: bytes to write
1223 * Write data to a tty device via the line discipline.
1226 * Locks the line discipline as required
1227 * Writes to the tty driver are serialized by the atomic_write_lock
1228 * and are then processed in chunks to the device. The line discipline
1229 * write method will not be invoked in parallel for each device.
1232 static ssize_t
tty_write(struct file
*file
, const char __user
*buf
,
1233 size_t count
, loff_t
*ppos
)
1235 struct tty_struct
*tty
= file_tty(file
);
1236 struct tty_ldisc
*ld
;
1239 if (tty_paranoia_check(tty
, file_inode(file
), "tty_write"))
1241 if (!tty
|| !tty
->ops
->write
||
1242 (test_bit(TTY_IO_ERROR
, &tty
->flags
)))
1244 /* Short term debug to catch buggy drivers */
1245 if (tty
->ops
->write_room
== NULL
)
1246 tty_err(tty
, "missing write_room method\n");
1247 ld
= tty_ldisc_ref_wait(tty
);
1248 if (!ld
->ops
->write
)
1251 ret
= do_tty_write(ld
->ops
->write
, tty
, file
, buf
, count
);
1252 tty_ldisc_deref(ld
);
1256 ssize_t
redirected_tty_write(struct file
*file
, const char __user
*buf
,
1257 size_t count
, loff_t
*ppos
)
1259 struct file
*p
= NULL
;
1261 spin_lock(&redirect_lock
);
1263 p
= get_file(redirect
);
1264 spin_unlock(&redirect_lock
);
1268 res
= vfs_write(p
, buf
, count
, &p
->f_pos
);
1272 return tty_write(file
, buf
, count
, ppos
);
1276 * tty_send_xchar - send priority character
1278 * Send a high priority character to the tty even if stopped
1280 * Locking: none for xchar method, write ordering for write method.
1283 int tty_send_xchar(struct tty_struct
*tty
, char ch
)
1285 int was_stopped
= tty
->stopped
;
1287 if (tty
->ops
->send_xchar
) {
1288 down_read(&tty
->termios_rwsem
);
1289 tty
->ops
->send_xchar(tty
, ch
);
1290 up_read(&tty
->termios_rwsem
);
1294 if (tty_write_lock(tty
, 0) < 0)
1295 return -ERESTARTSYS
;
1297 down_read(&tty
->termios_rwsem
);
1300 tty
->ops
->write(tty
, &ch
, 1);
1303 up_read(&tty
->termios_rwsem
);
1304 tty_write_unlock(tty
);
1308 static char ptychar
[] = "pqrstuvwxyzabcde";
1311 * pty_line_name - generate name for a pty
1312 * @driver: the tty driver in use
1313 * @index: the minor number
1314 * @p: output buffer of at least 6 bytes
1316 * Generate a name from a driver reference and write it to the output
1321 static void pty_line_name(struct tty_driver
*driver
, int index
, char *p
)
1323 int i
= index
+ driver
->name_base
;
1324 /* ->name is initialized to "ttyp", but "tty" is expected */
1325 sprintf(p
, "%s%c%x",
1326 driver
->subtype
== PTY_TYPE_SLAVE
? "tty" : driver
->name
,
1327 ptychar
[i
>> 4 & 0xf], i
& 0xf);
1331 * tty_line_name - generate name for a tty
1332 * @driver: the tty driver in use
1333 * @index: the minor number
1334 * @p: output buffer of at least 7 bytes
1336 * Generate a name from a driver reference and write it to the output
1341 static ssize_t
tty_line_name(struct tty_driver
*driver
, int index
, char *p
)
1343 if (driver
->flags
& TTY_DRIVER_UNNUMBERED_NODE
)
1344 return sprintf(p
, "%s", driver
->name
);
1346 return sprintf(p
, "%s%d", driver
->name
,
1347 index
+ driver
->name_base
);
1351 * tty_driver_lookup_tty() - find an existing tty, if any
1352 * @driver: the driver for the tty
1353 * @idx: the minor number
1355 * Return the tty, if found. If not found, return NULL or ERR_PTR() if the
1356 * driver lookup() method returns an error.
1358 * Locking: tty_mutex must be held. If the tty is found, bump the tty kref.
1360 static struct tty_struct
*tty_driver_lookup_tty(struct tty_driver
*driver
,
1361 struct inode
*inode
, int idx
)
1363 struct tty_struct
*tty
;
1365 if (driver
->ops
->lookup
)
1366 tty
= driver
->ops
->lookup(driver
, inode
, idx
);
1368 tty
= driver
->ttys
[idx
];
1376 * tty_init_termios - helper for termios setup
1377 * @tty: the tty to set up
1379 * Initialise the termios structures for this tty. Thus runs under
1380 * the tty_mutex currently so we can be relaxed about ordering.
1383 int tty_init_termios(struct tty_struct
*tty
)
1385 struct ktermios
*tp
;
1386 int idx
= tty
->index
;
1388 if (tty
->driver
->flags
& TTY_DRIVER_RESET_TERMIOS
)
1389 tty
->termios
= tty
->driver
->init_termios
;
1391 /* Check for lazy saved data */
1392 tp
= tty
->driver
->termios
[idx
];
1396 tty
->termios
= tty
->driver
->init_termios
;
1398 /* Compatibility until drivers always set this */
1399 tty
->termios
.c_ispeed
= tty_termios_input_baud_rate(&tty
->termios
);
1400 tty
->termios
.c_ospeed
= tty_termios_baud_rate(&tty
->termios
);
1403 EXPORT_SYMBOL_GPL(tty_init_termios
);
1405 int tty_standard_install(struct tty_driver
*driver
, struct tty_struct
*tty
)
1407 int ret
= tty_init_termios(tty
);
1411 tty_driver_kref_get(driver
);
1413 driver
->ttys
[tty
->index
] = tty
;
1416 EXPORT_SYMBOL_GPL(tty_standard_install
);
1419 * tty_driver_install_tty() - install a tty entry in the driver
1420 * @driver: the driver for the tty
1423 * Install a tty object into the driver tables. The tty->index field
1424 * will be set by the time this is called. This method is responsible
1425 * for ensuring any need additional structures are allocated and
1428 * Locking: tty_mutex for now
1430 static int tty_driver_install_tty(struct tty_driver
*driver
,
1431 struct tty_struct
*tty
)
1433 return driver
->ops
->install
? driver
->ops
->install(driver
, tty
) :
1434 tty_standard_install(driver
, tty
);
1438 * tty_driver_remove_tty() - remove a tty from the driver tables
1439 * @driver: the driver for the tty
1440 * @idx: the minor number
1442 * Remvoe a tty object from the driver tables. The tty->index field
1443 * will be set by the time this is called.
1445 * Locking: tty_mutex for now
1447 void tty_driver_remove_tty(struct tty_driver
*driver
, struct tty_struct
*tty
)
1449 if (driver
->ops
->remove
)
1450 driver
->ops
->remove(driver
, tty
);
1452 driver
->ttys
[tty
->index
] = NULL
;
1456 * tty_reopen() - fast re-open of an open tty
1457 * @tty - the tty to open
1459 * Return 0 on success, -errno on error.
1460 * Re-opens on master ptys are not allowed and return -EIO.
1462 * Locking: Caller must hold tty_lock
1464 static int tty_reopen(struct tty_struct
*tty
)
1466 struct tty_driver
*driver
= tty
->driver
;
1471 if (driver
->type
== TTY_DRIVER_TYPE_PTY
&&
1472 driver
->subtype
== PTY_TYPE_MASTER
)
1475 if (test_bit(TTY_EXCLUSIVE
, &tty
->flags
) && !capable(CAP_SYS_ADMIN
))
1480 WARN_ON(!tty
->ldisc
);
1486 * tty_init_dev - initialise a tty device
1487 * @driver: tty driver we are opening a device on
1488 * @idx: device index
1489 * @ret_tty: returned tty structure
1491 * Prepare a tty device. This may not be a "new" clean device but
1492 * could also be an active device. The pty drivers require special
1493 * handling because of this.
1496 * The function is called under the tty_mutex, which
1497 * protects us from the tty struct or driver itself going away.
1499 * On exit the tty device has the line discipline attached and
1500 * a reference count of 1. If a pair was created for pty/tty use
1501 * and the other was a pty master then it too has a reference count of 1.
1503 * WSH 06/09/97: Rewritten to remove races and properly clean up after a
1504 * failed open. The new code protects the open with a mutex, so it's
1505 * really quite straightforward. The mutex locking can probably be
1506 * relaxed for the (most common) case of reopening a tty.
1509 struct tty_struct
*tty_init_dev(struct tty_driver
*driver
, int idx
)
1511 struct tty_struct
*tty
;
1515 * First time open is complex, especially for PTY devices.
1516 * This code guarantees that either everything succeeds and the
1517 * TTY is ready for operation, or else the table slots are vacated
1518 * and the allocated memory released. (Except that the termios
1519 * and locked termios may be retained.)
1522 if (!try_module_get(driver
->owner
))
1523 return ERR_PTR(-ENODEV
);
1525 tty
= alloc_tty_struct(driver
, idx
);
1528 goto err_module_put
;
1532 retval
= tty_driver_install_tty(driver
, tty
);
1534 goto err_deinit_tty
;
1537 tty
->port
= driver
->ports
[idx
];
1539 WARN_RATELIMIT(!tty
->port
,
1540 "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n",
1541 __func__
, tty
->driver
->name
);
1543 tty
->port
->itty
= tty
;
1546 * Structures all installed ... call the ldisc open routines.
1547 * If we fail here just call release_tty to clean up. No need
1548 * to decrement the use counts, as release_tty doesn't care.
1550 retval
= tty_ldisc_setup(tty
, tty
->link
);
1552 goto err_release_tty
;
1553 /* Return the tty locked so that it cannot vanish under the caller */
1558 deinitialize_tty_struct(tty
);
1559 free_tty_struct(tty
);
1561 module_put(driver
->owner
);
1562 return ERR_PTR(retval
);
1564 /* call the tty release_tty routine to clean out this slot */
1567 tty_info_ratelimited(tty
, "ldisc open failed (%d), clearing slot %d\n",
1569 release_tty(tty
, idx
);
1570 return ERR_PTR(retval
);
1573 void tty_free_termios(struct tty_struct
*tty
)
1575 struct ktermios
*tp
;
1576 int idx
= tty
->index
;
1578 /* If the port is going to reset then it has no termios to save */
1579 if (tty
->driver
->flags
& TTY_DRIVER_RESET_TERMIOS
)
1582 /* Stash the termios data */
1583 tp
= tty
->driver
->termios
[idx
];
1585 tp
= kmalloc(sizeof(struct ktermios
), GFP_KERNEL
);
1588 tty
->driver
->termios
[idx
] = tp
;
1592 EXPORT_SYMBOL(tty_free_termios
);
1595 * tty_flush_works - flush all works of a tty/pty pair
1596 * @tty: tty device to flush works for (or either end of a pty pair)
1598 * Sync flush all works belonging to @tty (and the 'other' tty).
1600 static void tty_flush_works(struct tty_struct
*tty
)
1602 flush_work(&tty
->SAK_work
);
1603 flush_work(&tty
->hangup_work
);
1605 flush_work(&tty
->link
->SAK_work
);
1606 flush_work(&tty
->link
->hangup_work
);
1611 * release_one_tty - release tty structure memory
1612 * @kref: kref of tty we are obliterating
1614 * Releases memory associated with a tty structure, and clears out the
1615 * driver table slots. This function is called when a device is no longer
1616 * in use. It also gets called when setup of a device fails.
1619 * takes the file list lock internally when working on the list
1620 * of ttys that the driver keeps.
1622 * This method gets called from a work queue so that the driver private
1623 * cleanup ops can sleep (needed for USB at least)
1625 static void release_one_tty(struct work_struct
*work
)
1627 struct tty_struct
*tty
=
1628 container_of(work
, struct tty_struct
, hangup_work
);
1629 struct tty_driver
*driver
= tty
->driver
;
1630 struct module
*owner
= driver
->owner
;
1632 if (tty
->ops
->cleanup
)
1633 tty
->ops
->cleanup(tty
);
1636 tty_driver_kref_put(driver
);
1639 spin_lock(&tty_files_lock
);
1640 list_del_init(&tty
->tty_files
);
1641 spin_unlock(&tty_files_lock
);
1644 put_pid(tty
->session
);
1645 free_tty_struct(tty
);
1648 static void queue_release_one_tty(struct kref
*kref
)
1650 struct tty_struct
*tty
= container_of(kref
, struct tty_struct
, kref
);
1652 /* The hangup queue is now free so we can reuse it rather than
1653 waste a chunk of memory for each port */
1654 INIT_WORK(&tty
->hangup_work
, release_one_tty
);
1655 schedule_work(&tty
->hangup_work
);
1659 * tty_kref_put - release a tty kref
1662 * Release a reference to a tty device and if need be let the kref
1663 * layer destruct the object for us
1666 void tty_kref_put(struct tty_struct
*tty
)
1669 kref_put(&tty
->kref
, queue_release_one_tty
);
1671 EXPORT_SYMBOL(tty_kref_put
);
1674 * release_tty - release tty structure memory
1676 * Release both @tty and a possible linked partner (think pty pair),
1677 * and decrement the refcount of the backing module.
1681 * takes the file list lock internally when working on the list
1682 * of ttys that the driver keeps.
1685 static void release_tty(struct tty_struct
*tty
, int idx
)
1687 /* This should always be true but check for the moment */
1688 WARN_ON(tty
->index
!= idx
);
1689 WARN_ON(!mutex_is_locked(&tty_mutex
));
1690 if (tty
->ops
->shutdown
)
1691 tty
->ops
->shutdown(tty
);
1692 tty_free_termios(tty
);
1693 tty_driver_remove_tty(tty
->driver
, tty
);
1694 tty
->port
->itty
= NULL
;
1696 tty
->link
->port
->itty
= NULL
;
1697 tty_buffer_cancel_work(tty
->port
);
1699 tty_kref_put(tty
->link
);
1704 * tty_release_checks - check a tty before real release
1705 * @tty: tty to check
1706 * @o_tty: link of @tty (if any)
1707 * @idx: index of the tty
1709 * Performs some paranoid checking before true release of the @tty.
1710 * This is a no-op unless TTY_PARANOIA_CHECK is defined.
1712 static int tty_release_checks(struct tty_struct
*tty
, int idx
)
1714 #ifdef TTY_PARANOIA_CHECK
1715 if (idx
< 0 || idx
>= tty
->driver
->num
) {
1716 tty_debug(tty
, "bad idx %d\n", idx
);
1720 /* not much to check for devpts */
1721 if (tty
->driver
->flags
& TTY_DRIVER_DEVPTS_MEM
)
1724 if (tty
!= tty
->driver
->ttys
[idx
]) {
1725 tty_debug(tty
, "bad driver table[%d] = %p\n",
1726 idx
, tty
->driver
->ttys
[idx
]);
1729 if (tty
->driver
->other
) {
1730 struct tty_struct
*o_tty
= tty
->link
;
1732 if (o_tty
!= tty
->driver
->other
->ttys
[idx
]) {
1733 tty_debug(tty
, "bad other table[%d] = %p\n",
1734 idx
, tty
->driver
->other
->ttys
[idx
]);
1737 if (o_tty
->link
!= tty
) {
1738 tty_debug(tty
, "bad link = %p\n", o_tty
->link
);
1747 * tty_release - vfs callback for close
1748 * @inode: inode of tty
1749 * @filp: file pointer for handle to tty
1751 * Called the last time each file handle is closed that references
1752 * this tty. There may however be several such references.
1755 * Takes bkl. See tty_release_dev
1757 * Even releasing the tty structures is a tricky business.. We have
1758 * to be very careful that the structures are all released at the
1759 * same time, as interrupts might otherwise get the wrong pointers.
1761 * WSH 09/09/97: rewritten to avoid some nasty race conditions that could
1762 * lead to double frees or releasing memory still in use.
1765 int tty_release(struct inode
*inode
, struct file
*filp
)
1767 struct tty_struct
*tty
= file_tty(filp
);
1768 struct tty_struct
*o_tty
= NULL
;
1769 int do_sleep
, final
;
1774 if (tty_paranoia_check(tty
, inode
, __func__
))
1778 check_tty_count(tty
, __func__
);
1780 __tty_fasync(-1, filp
, 0);
1783 if (tty
->driver
->type
== TTY_DRIVER_TYPE_PTY
&&
1784 tty
->driver
->subtype
== PTY_TYPE_MASTER
)
1787 if (tty_release_checks(tty
, idx
)) {
1792 tty_debug_hangup(tty
, "(tty count=%d)...\n", tty
->count
);
1794 if (tty
->ops
->close
)
1795 tty
->ops
->close(tty
, filp
);
1797 /* If tty is pty master, lock the slave pty (stable lock order) */
1798 tty_lock_slave(o_tty
);
1801 * Sanity check: if tty->count is going to zero, there shouldn't be
1802 * any waiters on tty->read_wait or tty->write_wait. We test the
1803 * wait queues and kick everyone out _before_ actually starting to
1804 * close. This ensures that we won't block while releasing the tty
1807 * The test for the o_tty closing is necessary, since the master and
1808 * slave sides may close in any order. If the slave side closes out
1809 * first, its count will be one, since the master side holds an open.
1810 * Thus this test wouldn't be triggered at the time the slave closed,
1816 if (tty
->count
<= 1) {
1817 if (waitqueue_active(&tty
->read_wait
)) {
1818 wake_up_poll(&tty
->read_wait
, POLLIN
);
1821 if (waitqueue_active(&tty
->write_wait
)) {
1822 wake_up_poll(&tty
->write_wait
, POLLOUT
);
1826 if (o_tty
&& o_tty
->count
<= 1) {
1827 if (waitqueue_active(&o_tty
->read_wait
)) {
1828 wake_up_poll(&o_tty
->read_wait
, POLLIN
);
1831 if (waitqueue_active(&o_tty
->write_wait
)) {
1832 wake_up_poll(&o_tty
->write_wait
, POLLOUT
);
1841 tty_warn(tty
, "read/write wait queue active!\n");
1843 schedule_timeout_killable(timeout
);
1844 if (timeout
< 120 * HZ
)
1845 timeout
= 2 * timeout
+ 1;
1847 timeout
= MAX_SCHEDULE_TIMEOUT
;
1851 if (--o_tty
->count
< 0) {
1852 tty_warn(tty
, "bad slave count (%d)\n", o_tty
->count
);
1856 if (--tty
->count
< 0) {
1857 tty_warn(tty
, "bad tty->count (%d)\n", tty
->count
);
1862 * We've decremented tty->count, so we need to remove this file
1863 * descriptor off the tty->tty_files list; this serves two
1865 * - check_tty_count sees the correct number of file descriptors
1866 * associated with this tty.
1867 * - do_tty_hangup no longer sees this file descriptor as
1868 * something that needs to be handled for hangups.
1873 * Perform some housekeeping before deciding whether to return.
1875 * If _either_ side is closing, make sure there aren't any
1876 * processes that still think tty or o_tty is their controlling
1880 read_lock(&tasklist_lock
);
1881 session_clear_tty(tty
->session
);
1883 session_clear_tty(o_tty
->session
);
1884 read_unlock(&tasklist_lock
);
1887 /* check whether both sides are closing ... */
1888 final
= !tty
->count
&& !(o_tty
&& o_tty
->count
);
1890 tty_unlock_slave(o_tty
);
1893 /* At this point, the tty->count == 0 should ensure a dead tty
1894 cannot be re-opened by a racing opener */
1899 tty_debug_hangup(tty
, "final close\n");
1901 * Ask the line discipline code to release its structures
1903 tty_ldisc_release(tty
);
1905 /* Wait for pending work before tty destruction commmences */
1906 tty_flush_works(tty
);
1908 tty_debug_hangup(tty
, "freeing structure...\n");
1910 * The release_tty function takes care of the details of clearing
1911 * the slots and preserving the termios structure. The tty_unlock_pair
1912 * should be safe as we keep a kref while the tty is locked (so the
1913 * unlock never unlocks a freed tty).
1915 mutex_lock(&tty_mutex
);
1916 release_tty(tty
, idx
);
1917 mutex_unlock(&tty_mutex
);
1923 * tty_open_current_tty - get locked tty of current task
1924 * @device: device number
1925 * @filp: file pointer to tty
1926 * @return: locked tty of the current task iff @device is /dev/tty
1928 * Performs a re-open of the current task's controlling tty.
1930 * We cannot return driver and index like for the other nodes because
1931 * devpts will not work then. It expects inodes to be from devpts FS.
1933 static struct tty_struct
*tty_open_current_tty(dev_t device
, struct file
*filp
)
1935 struct tty_struct
*tty
;
1938 if (device
!= MKDEV(TTYAUX_MAJOR
, 0))
1941 tty
= get_current_tty();
1943 return ERR_PTR(-ENXIO
);
1945 filp
->f_flags
|= O_NONBLOCK
; /* Don't let /dev/tty block */
1948 tty_kref_put(tty
); /* safe to drop the kref now */
1950 retval
= tty_reopen(tty
);
1953 tty
= ERR_PTR(retval
);
1959 * tty_lookup_driver - lookup a tty driver for a given device file
1960 * @device: device number
1961 * @filp: file pointer to tty
1962 * @noctty: set if the device should not become a controlling tty
1963 * @index: index for the device in the @return driver
1964 * @return: driver for this inode (with increased refcount)
1966 * If @return is not erroneous, the caller is responsible to decrement the
1967 * refcount by tty_driver_kref_put.
1969 * Locking: tty_mutex protects get_tty_driver
1971 static struct tty_driver
*tty_lookup_driver(dev_t device
, struct file
*filp
,
1972 int *noctty
, int *index
)
1974 struct tty_driver
*driver
;
1978 case MKDEV(TTY_MAJOR
, 0): {
1979 extern struct tty_driver
*console_driver
;
1980 driver
= tty_driver_kref_get(console_driver
);
1981 *index
= fg_console
;
1986 case MKDEV(TTYAUX_MAJOR
, 1): {
1987 struct tty_driver
*console_driver
= console_device(index
);
1988 if (console_driver
) {
1989 driver
= tty_driver_kref_get(console_driver
);
1991 /* Don't let /dev/console block */
1992 filp
->f_flags
|= O_NONBLOCK
;
1997 return ERR_PTR(-ENODEV
);
2000 driver
= get_tty_driver(device
, index
);
2002 return ERR_PTR(-ENODEV
);
2009 * tty_open - open a tty device
2010 * @inode: inode of device file
2011 * @filp: file pointer to tty
2013 * tty_open and tty_release keep up the tty count that contains the
2014 * number of opens done on a tty. We cannot use the inode-count, as
2015 * different inodes might point to the same tty.
2017 * Open-counting is needed for pty masters, as well as for keeping
2018 * track of serial lines: DTR is dropped when the last close happens.
2019 * (This is not done solely through tty->count, now. - Ted 1/27/92)
2021 * The termios state of a pty is reset on first open so that
2022 * settings don't persist across reuse.
2024 * Locking: tty_mutex protects tty, tty_lookup_driver and tty_init_dev.
2025 * tty->count should protect the rest.
2026 * ->siglock protects ->signal/->sighand
2028 * Note: the tty_unlock/lock cases without a ref are only safe due to
2032 static int tty_open(struct inode
*inode
, struct file
*filp
)
2034 struct tty_struct
*tty
;
2036 struct tty_driver
*driver
= NULL
;
2038 dev_t device
= inode
->i_rdev
;
2039 unsigned saved_flags
= filp
->f_flags
;
2041 nonseekable_open(inode
, filp
);
2044 retval
= tty_alloc_file(filp
);
2048 noctty
= filp
->f_flags
& O_NOCTTY
;
2052 tty
= tty_open_current_tty(device
, filp
);
2054 mutex_lock(&tty_mutex
);
2055 driver
= tty_lookup_driver(device
, filp
, &noctty
, &index
);
2056 if (IS_ERR(driver
)) {
2057 retval
= PTR_ERR(driver
);
2061 /* check whether we're reopening an existing tty */
2062 tty
= tty_driver_lookup_tty(driver
, inode
, index
);
2064 retval
= PTR_ERR(tty
);
2069 mutex_unlock(&tty_mutex
);
2071 /* safe to drop the kref from tty_driver_lookup_tty() */
2073 retval
= tty_reopen(tty
);
2076 tty
= ERR_PTR(retval
);
2078 } else { /* Returns with the tty_lock held for now */
2079 tty
= tty_init_dev(driver
, index
);
2080 mutex_unlock(&tty_mutex
);
2083 tty_driver_kref_put(driver
);
2087 retval
= PTR_ERR(tty
);
2091 tty_add_file(tty
, filp
);
2093 check_tty_count(tty
, __func__
);
2094 if (tty
->driver
->type
== TTY_DRIVER_TYPE_PTY
&&
2095 tty
->driver
->subtype
== PTY_TYPE_MASTER
)
2098 tty_debug_hangup(tty
, "(tty count=%d)\n", tty
->count
);
2101 retval
= tty
->ops
->open(tty
, filp
);
2104 filp
->f_flags
= saved_flags
;
2107 tty_debug_hangup(tty
, "error %d, releasing...\n", retval
);
2109 tty_unlock(tty
); /* need to call tty_release without BTM */
2110 tty_release(inode
, filp
);
2111 if (retval
!= -ERESTARTSYS
)
2114 if (signal_pending(current
))
2119 * Need to reset f_op in case a hangup happened.
2121 if (tty_hung_up_p(filp
))
2122 filp
->f_op
= &tty_fops
;
2125 clear_bit(TTY_HUPPED
, &tty
->flags
);
2128 read_lock(&tasklist_lock
);
2129 spin_lock_irq(¤t
->sighand
->siglock
);
2131 current
->signal
->leader
&&
2132 !current
->signal
->tty
&&
2133 tty
->session
== NULL
) {
2135 * Don't let a process that only has write access to the tty
2136 * obtain the privileges associated with having a tty as
2137 * controlling terminal (being able to reopen it with full
2138 * access through /dev/tty, being able to perform pushback).
2139 * Many distributions set the group of all ttys to "tty" and
2140 * grant write-only access to all terminals for setgid tty
2141 * binaries, which should not imply full privileges on all ttys.
2143 * This could theoretically break old code that performs open()
2144 * on a write-only file descriptor. In that case, it might be
2145 * necessary to also permit this if
2146 * inode_permission(inode, MAY_READ) == 0.
2148 if (filp
->f_mode
& FMODE_READ
)
2149 __proc_set_tty(tty
);
2151 spin_unlock_irq(¤t
->sighand
->siglock
);
2152 read_unlock(&tasklist_lock
);
2156 mutex_unlock(&tty_mutex
);
2157 /* after locks to avoid deadlock */
2158 if (!IS_ERR_OR_NULL(driver
))
2159 tty_driver_kref_put(driver
);
2161 tty_free_file(filp
);
2168 * tty_poll - check tty status
2169 * @filp: file being polled
2170 * @wait: poll wait structures to update
2172 * Call the line discipline polling method to obtain the poll
2173 * status of the device.
2175 * Locking: locks called line discipline but ldisc poll method
2176 * may be re-entered freely by other callers.
2179 static unsigned int tty_poll(struct file
*filp
, poll_table
*wait
)
2181 struct tty_struct
*tty
= file_tty(filp
);
2182 struct tty_ldisc
*ld
;
2185 if (tty_paranoia_check(tty
, file_inode(filp
), "tty_poll"))
2188 ld
= tty_ldisc_ref_wait(tty
);
2190 ret
= ld
->ops
->poll(tty
, filp
, wait
);
2191 tty_ldisc_deref(ld
);
2195 static int __tty_fasync(int fd
, struct file
*filp
, int on
)
2197 struct tty_struct
*tty
= file_tty(filp
);
2198 struct tty_ldisc
*ldisc
;
2199 unsigned long flags
;
2202 if (tty_paranoia_check(tty
, file_inode(filp
), "tty_fasync"))
2205 retval
= fasync_helper(fd
, filp
, on
, &tty
->fasync
);
2209 ldisc
= tty_ldisc_ref(tty
);
2211 if (ldisc
->ops
->fasync
)
2212 ldisc
->ops
->fasync(tty
, on
);
2213 tty_ldisc_deref(ldisc
);
2220 spin_lock_irqsave(&tty
->ctrl_lock
, flags
);
2223 type
= PIDTYPE_PGID
;
2225 pid
= task_pid(current
);
2229 spin_unlock_irqrestore(&tty
->ctrl_lock
, flags
);
2230 __f_setown(filp
, pid
, type
, 0);
2238 static int tty_fasync(int fd
, struct file
*filp
, int on
)
2240 struct tty_struct
*tty
= file_tty(filp
);
2244 retval
= __tty_fasync(fd
, filp
, on
);
2251 * tiocsti - fake input character
2252 * @tty: tty to fake input into
2253 * @p: pointer to character
2255 * Fake input to a tty device. Does the necessary locking and
2258 * FIXME: does not honour flow control ??
2261 * Called functions take tty_ldiscs_lock
2262 * current->signal->tty check is safe without locks
2264 * FIXME: may race normal receive processing
2267 static int tiocsti(struct tty_struct
*tty
, char __user
*p
)
2270 struct tty_ldisc
*ld
;
2272 if ((current
->signal
->tty
!= tty
) && !capable(CAP_SYS_ADMIN
))
2274 if (get_user(ch
, p
))
2276 tty_audit_tiocsti(tty
, ch
);
2277 ld
= tty_ldisc_ref_wait(tty
);
2278 ld
->ops
->receive_buf(tty
, &ch
, &mbz
, 1);
2279 tty_ldisc_deref(ld
);
2284 * tiocgwinsz - implement window query ioctl
2286 * @arg: user buffer for result
2288 * Copies the kernel idea of the window size into the user buffer.
2290 * Locking: tty->winsize_mutex is taken to ensure the winsize data
2294 static int tiocgwinsz(struct tty_struct
*tty
, struct winsize __user
*arg
)
2298 mutex_lock(&tty
->winsize_mutex
);
2299 err
= copy_to_user(arg
, &tty
->winsize
, sizeof(*arg
));
2300 mutex_unlock(&tty
->winsize_mutex
);
2302 return err
? -EFAULT
: 0;
2306 * tty_do_resize - resize event
2307 * @tty: tty being resized
2308 * @rows: rows (character)
2309 * @cols: cols (character)
2311 * Update the termios variables and send the necessary signals to
2312 * peform a terminal resize correctly
2315 int tty_do_resize(struct tty_struct
*tty
, struct winsize
*ws
)
2320 mutex_lock(&tty
->winsize_mutex
);
2321 if (!memcmp(ws
, &tty
->winsize
, sizeof(*ws
)))
2324 /* Signal the foreground process group */
2325 pgrp
= tty_get_pgrp(tty
);
2327 kill_pgrp(pgrp
, SIGWINCH
, 1);
2332 mutex_unlock(&tty
->winsize_mutex
);
2335 EXPORT_SYMBOL(tty_do_resize
);
2338 * tiocswinsz - implement window size set ioctl
2339 * @tty; tty side of tty
2340 * @arg: user buffer for result
2342 * Copies the user idea of the window size to the kernel. Traditionally
2343 * this is just advisory information but for the Linux console it
2344 * actually has driver level meaning and triggers a VC resize.
2347 * Driver dependent. The default do_resize method takes the
2348 * tty termios mutex and ctrl_lock. The console takes its own lock
2349 * then calls into the default method.
2352 static int tiocswinsz(struct tty_struct
*tty
, struct winsize __user
*arg
)
2354 struct winsize tmp_ws
;
2355 if (copy_from_user(&tmp_ws
, arg
, sizeof(*arg
)))
2358 if (tty
->ops
->resize
)
2359 return tty
->ops
->resize(tty
, &tmp_ws
);
2361 return tty_do_resize(tty
, &tmp_ws
);
2365 * tioccons - allow admin to move logical console
2366 * @file: the file to become console
2368 * Allow the administrator to move the redirected console device
2370 * Locking: uses redirect_lock to guard the redirect information
2373 static int tioccons(struct file
*file
)
2375 if (!capable(CAP_SYS_ADMIN
))
2377 if (file
->f_op
->write
== redirected_tty_write
) {
2379 spin_lock(&redirect_lock
);
2382 spin_unlock(&redirect_lock
);
2387 spin_lock(&redirect_lock
);
2389 spin_unlock(&redirect_lock
);
2392 redirect
= get_file(file
);
2393 spin_unlock(&redirect_lock
);
2398 * fionbio - non blocking ioctl
2399 * @file: file to set blocking value
2400 * @p: user parameter
2402 * Historical tty interfaces had a blocking control ioctl before
2403 * the generic functionality existed. This piece of history is preserved
2404 * in the expected tty API of posix OS's.
2406 * Locking: none, the open file handle ensures it won't go away.
2409 static int fionbio(struct file
*file
, int __user
*p
)
2413 if (get_user(nonblock
, p
))
2416 spin_lock(&file
->f_lock
);
2418 file
->f_flags
|= O_NONBLOCK
;
2420 file
->f_flags
&= ~O_NONBLOCK
;
2421 spin_unlock(&file
->f_lock
);
2426 * tiocsctty - set controlling tty
2427 * @tty: tty structure
2428 * @arg: user argument
2430 * This ioctl is used to manage job control. It permits a session
2431 * leader to set this tty as the controlling tty for the session.
2434 * Takes tty_lock() to serialize proc_set_tty() for this tty
2435 * Takes tasklist_lock internally to walk sessions
2436 * Takes ->siglock() when updating signal->tty
2439 static int tiocsctty(struct tty_struct
*tty
, struct file
*file
, int arg
)
2444 read_lock(&tasklist_lock
);
2446 if (current
->signal
->leader
&& (task_session(current
) == tty
->session
))
2450 * The process must be a session leader and
2451 * not have a controlling tty already.
2453 if (!current
->signal
->leader
|| current
->signal
->tty
) {
2460 * This tty is already the controlling
2461 * tty for another session group!
2463 if (arg
== 1 && capable(CAP_SYS_ADMIN
)) {
2467 session_clear_tty(tty
->session
);
2474 /* See the comment in tty_open(). */
2475 if ((file
->f_mode
& FMODE_READ
) == 0 && !capable(CAP_SYS_ADMIN
)) {
2482 read_unlock(&tasklist_lock
);
2488 * tty_get_pgrp - return a ref counted pgrp pid
2491 * Returns a refcounted instance of the pid struct for the process
2492 * group controlling the tty.
2495 struct pid
*tty_get_pgrp(struct tty_struct
*tty
)
2497 unsigned long flags
;
2500 spin_lock_irqsave(&tty
->ctrl_lock
, flags
);
2501 pgrp
= get_pid(tty
->pgrp
);
2502 spin_unlock_irqrestore(&tty
->ctrl_lock
, flags
);
2506 EXPORT_SYMBOL_GPL(tty_get_pgrp
);
2509 * This checks not only the pgrp, but falls back on the pid if no
2510 * satisfactory pgrp is found. I dunno - gdb doesn't work correctly
2513 * The caller must hold rcu lock or the tasklist lock.
2515 static struct pid
*session_of_pgrp(struct pid
*pgrp
)
2517 struct task_struct
*p
;
2518 struct pid
*sid
= NULL
;
2520 p
= pid_task(pgrp
, PIDTYPE_PGID
);
2522 p
= pid_task(pgrp
, PIDTYPE_PID
);
2524 sid
= task_session(p
);
2530 * tiocgpgrp - get process group
2531 * @tty: tty passed by user
2532 * @real_tty: tty side of the tty passed by the user if a pty else the tty
2535 * Obtain the process group of the tty. If there is no process group
2538 * Locking: none. Reference to current->signal->tty is safe.
2541 static int tiocgpgrp(struct tty_struct
*tty
, struct tty_struct
*real_tty
, pid_t __user
*p
)
2546 * (tty == real_tty) is a cheap way of
2547 * testing if the tty is NOT a master pty.
2549 if (tty
== real_tty
&& current
->signal
->tty
!= real_tty
)
2551 pid
= tty_get_pgrp(real_tty
);
2552 ret
= put_user(pid_vnr(pid
), p
);
2558 * tiocspgrp - attempt to set process group
2559 * @tty: tty passed by user
2560 * @real_tty: tty side device matching tty passed by user
2563 * Set the process group of the tty to the session passed. Only
2564 * permitted where the tty session is our session.
2566 * Locking: RCU, ctrl lock
2569 static int tiocspgrp(struct tty_struct
*tty
, struct tty_struct
*real_tty
, pid_t __user
*p
)
2573 int retval
= tty_check_change(real_tty
);
2579 if (!current
->signal
->tty
||
2580 (current
->signal
->tty
!= real_tty
) ||
2581 (real_tty
->session
!= task_session(current
)))
2583 if (get_user(pgrp_nr
, p
))
2588 pgrp
= find_vpid(pgrp_nr
);
2593 if (session_of_pgrp(pgrp
) != task_session(current
))
2596 spin_lock_irq(&tty
->ctrl_lock
);
2597 put_pid(real_tty
->pgrp
);
2598 real_tty
->pgrp
= get_pid(pgrp
);
2599 spin_unlock_irq(&tty
->ctrl_lock
);
2606 * tiocgsid - get session id
2607 * @tty: tty passed by user
2608 * @real_tty: tty side of the tty passed by the user if a pty else the tty
2609 * @p: pointer to returned session id
2611 * Obtain the session id of the tty. If there is no session
2614 * Locking: none. Reference to current->signal->tty is safe.
2617 static int tiocgsid(struct tty_struct
*tty
, struct tty_struct
*real_tty
, pid_t __user
*p
)
2620 * (tty == real_tty) is a cheap way of
2621 * testing if the tty is NOT a master pty.
2623 if (tty
== real_tty
&& current
->signal
->tty
!= real_tty
)
2625 if (!real_tty
->session
)
2627 return put_user(pid_vnr(real_tty
->session
), p
);
2631 * tiocsetd - set line discipline
2633 * @p: pointer to user data
2635 * Set the line discipline according to user request.
2637 * Locking: see tty_set_ldisc, this function is just a helper
2640 static int tiocsetd(struct tty_struct
*tty
, int __user
*p
)
2645 if (get_user(ldisc
, p
))
2648 ret
= tty_set_ldisc(tty
, ldisc
);
2654 * send_break - performed time break
2655 * @tty: device to break on
2656 * @duration: timeout in mS
2658 * Perform a timed break on hardware that lacks its own driver level
2659 * timed break functionality.
2662 * atomic_write_lock serializes
2666 static int send_break(struct tty_struct
*tty
, unsigned int duration
)
2670 if (tty
->ops
->break_ctl
== NULL
)
2673 if (tty
->driver
->flags
& TTY_DRIVER_HARDWARE_BREAK
)
2674 retval
= tty
->ops
->break_ctl(tty
, duration
);
2676 /* Do the work ourselves */
2677 if (tty_write_lock(tty
, 0) < 0)
2679 retval
= tty
->ops
->break_ctl(tty
, -1);
2682 if (!signal_pending(current
))
2683 msleep_interruptible(duration
);
2684 retval
= tty
->ops
->break_ctl(tty
, 0);
2686 tty_write_unlock(tty
);
2687 if (signal_pending(current
))
2694 * tty_tiocmget - get modem status
2696 * @file: user file pointer
2697 * @p: pointer to result
2699 * Obtain the modem status bits from the tty driver if the feature
2700 * is supported. Return -EINVAL if it is not available.
2702 * Locking: none (up to the driver)
2705 static int tty_tiocmget(struct tty_struct
*tty
, int __user
*p
)
2707 int retval
= -EINVAL
;
2709 if (tty
->ops
->tiocmget
) {
2710 retval
= tty
->ops
->tiocmget(tty
);
2713 retval
= put_user(retval
, p
);
2719 * tty_tiocmset - set modem status
2721 * @cmd: command - clear bits, set bits or set all
2722 * @p: pointer to desired bits
2724 * Set the modem status bits from the tty driver if the feature
2725 * is supported. Return -EINVAL if it is not available.
2727 * Locking: none (up to the driver)
2730 static int tty_tiocmset(struct tty_struct
*tty
, unsigned int cmd
,
2734 unsigned int set
, clear
, val
;
2736 if (tty
->ops
->tiocmset
== NULL
)
2739 retval
= get_user(val
, p
);
2755 set
&= TIOCM_DTR
|TIOCM_RTS
|TIOCM_OUT1
|TIOCM_OUT2
|TIOCM_LOOP
;
2756 clear
&= TIOCM_DTR
|TIOCM_RTS
|TIOCM_OUT1
|TIOCM_OUT2
|TIOCM_LOOP
;
2757 return tty
->ops
->tiocmset(tty
, set
, clear
);
2760 static int tty_tiocgicount(struct tty_struct
*tty
, void __user
*arg
)
2762 int retval
= -EINVAL
;
2763 struct serial_icounter_struct icount
;
2764 memset(&icount
, 0, sizeof(icount
));
2765 if (tty
->ops
->get_icount
)
2766 retval
= tty
->ops
->get_icount(tty
, &icount
);
2769 if (copy_to_user(arg
, &icount
, sizeof(icount
)))
2774 static void tty_warn_deprecated_flags(struct serial_struct __user
*ss
)
2776 static DEFINE_RATELIMIT_STATE(depr_flags
,
2777 DEFAULT_RATELIMIT_INTERVAL
,
2778 DEFAULT_RATELIMIT_BURST
);
2779 char comm
[TASK_COMM_LEN
];
2782 if (get_user(flags
, &ss
->flags
))
2785 flags
&= ASYNC_DEPRECATED
;
2787 if (flags
&& __ratelimit(&depr_flags
))
2788 pr_warning("%s: '%s' is using deprecated serial flags (with no effect): %.8x\n",
2789 __func__
, get_task_comm(comm
, current
), flags
);
2793 * if pty, return the slave side (real_tty)
2794 * otherwise, return self
2796 static struct tty_struct
*tty_pair_get_tty(struct tty_struct
*tty
)
2798 if (tty
->driver
->type
== TTY_DRIVER_TYPE_PTY
&&
2799 tty
->driver
->subtype
== PTY_TYPE_MASTER
)
2805 * Split this up, as gcc can choke on it otherwise..
2807 long tty_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
2809 struct tty_struct
*tty
= file_tty(file
);
2810 struct tty_struct
*real_tty
;
2811 void __user
*p
= (void __user
*)arg
;
2813 struct tty_ldisc
*ld
;
2815 if (tty_paranoia_check(tty
, file_inode(file
), "tty_ioctl"))
2818 real_tty
= tty_pair_get_tty(tty
);
2821 * Factor out some common prep work
2829 retval
= tty_check_change(tty
);
2832 if (cmd
!= TIOCCBRK
) {
2833 tty_wait_until_sent(tty
, 0);
2834 if (signal_pending(current
))
2845 return tiocsti(tty
, p
);
2847 return tiocgwinsz(real_tty
, p
);
2849 return tiocswinsz(real_tty
, p
);
2851 return real_tty
!= tty
? -EINVAL
: tioccons(file
);
2853 return fionbio(file
, p
);
2855 set_bit(TTY_EXCLUSIVE
, &tty
->flags
);
2858 clear_bit(TTY_EXCLUSIVE
, &tty
->flags
);
2862 int excl
= test_bit(TTY_EXCLUSIVE
, &tty
->flags
);
2863 return put_user(excl
, (int __user
*)p
);
2866 if (current
->signal
->tty
!= tty
)
2871 return tiocsctty(tty
, file
, arg
);
2873 return tiocgpgrp(tty
, real_tty
, p
);
2875 return tiocspgrp(tty
, real_tty
, p
);
2877 return tiocgsid(tty
, real_tty
, p
);
2879 return put_user(tty
->ldisc
->ops
->num
, (int __user
*)p
);
2881 return tiocsetd(tty
, p
);
2883 if (!capable(CAP_SYS_ADMIN
))
2889 unsigned int ret
= new_encode_dev(tty_devnum(real_tty
));
2890 return put_user(ret
, (unsigned int __user
*)p
);
2895 case TIOCSBRK
: /* Turn break on, unconditionally */
2896 if (tty
->ops
->break_ctl
)
2897 return tty
->ops
->break_ctl(tty
, -1);
2899 case TIOCCBRK
: /* Turn break off, unconditionally */
2900 if (tty
->ops
->break_ctl
)
2901 return tty
->ops
->break_ctl(tty
, 0);
2903 case TCSBRK
: /* SVID version: non-zero arg --> no break */
2904 /* non-zero arg means wait for all output data
2905 * to be sent (performed above) but don't send break.
2906 * This is used by the tcdrain() termios function.
2909 return send_break(tty
, 250);
2911 case TCSBRKP
: /* support for POSIX tcsendbreak() */
2912 return send_break(tty
, arg
? arg
*100 : 250);
2915 return tty_tiocmget(tty
, p
);
2919 return tty_tiocmset(tty
, cmd
, p
);
2921 retval
= tty_tiocgicount(tty
, p
);
2922 /* For the moment allow fall through to the old method */
2923 if (retval
!= -EINVAL
)
2930 /* flush tty buffer and allow ldisc to process ioctl */
2931 tty_buffer_flush(tty
, NULL
);
2936 tty_warn_deprecated_flags(p
);
2939 if (tty
->ops
->ioctl
) {
2940 retval
= tty
->ops
->ioctl(tty
, cmd
, arg
);
2941 if (retval
!= -ENOIOCTLCMD
)
2944 ld
= tty_ldisc_ref_wait(tty
);
2946 if (ld
->ops
->ioctl
) {
2947 retval
= ld
->ops
->ioctl(tty
, file
, cmd
, arg
);
2948 if (retval
== -ENOIOCTLCMD
)
2951 tty_ldisc_deref(ld
);
2955 #ifdef CONFIG_COMPAT
2956 static long tty_compat_ioctl(struct file
*file
, unsigned int cmd
,
2959 struct tty_struct
*tty
= file_tty(file
);
2960 struct tty_ldisc
*ld
;
2961 int retval
= -ENOIOCTLCMD
;
2963 if (tty_paranoia_check(tty
, file_inode(file
), "tty_ioctl"))
2966 if (tty
->ops
->compat_ioctl
) {
2967 retval
= tty
->ops
->compat_ioctl(tty
, cmd
, arg
);
2968 if (retval
!= -ENOIOCTLCMD
)
2972 ld
= tty_ldisc_ref_wait(tty
);
2973 if (ld
->ops
->compat_ioctl
)
2974 retval
= ld
->ops
->compat_ioctl(tty
, file
, cmd
, arg
);
2976 retval
= n_tty_compat_ioctl_helper(tty
, file
, cmd
, arg
);
2977 tty_ldisc_deref(ld
);
2983 static int this_tty(const void *t
, struct file
*file
, unsigned fd
)
2985 if (likely(file
->f_op
->read
!= tty_read
))
2987 return file_tty(file
) != t
? 0 : fd
+ 1;
2991 * This implements the "Secure Attention Key" --- the idea is to
2992 * prevent trojan horses by killing all processes associated with this
2993 * tty when the user hits the "Secure Attention Key". Required for
2994 * super-paranoid applications --- see the Orange Book for more details.
2996 * This code could be nicer; ideally it should send a HUP, wait a few
2997 * seconds, then send a INT, and then a KILL signal. But you then
2998 * have to coordinate with the init process, since all processes associated
2999 * with the current tty must be dead before the new getty is allowed
3002 * Now, if it would be correct ;-/ The current code has a nasty hole -
3003 * it doesn't catch files in flight. We may send the descriptor to ourselves
3004 * via AF_UNIX socket, close it and later fetch from socket. FIXME.
3006 * Nasty bug: do_SAK is being called in interrupt context. This can
3007 * deadlock. We punt it up to process context. AKPM - 16Mar2001
3009 void __do_SAK(struct tty_struct
*tty
)
3014 struct task_struct
*g
, *p
;
3015 struct pid
*session
;
3020 session
= tty
->session
;
3022 tty_ldisc_flush(tty
);
3024 tty_driver_flush_buffer(tty
);
3026 read_lock(&tasklist_lock
);
3027 /* Kill the entire session */
3028 do_each_pid_task(session
, PIDTYPE_SID
, p
) {
3029 tty_notice(tty
, "SAK: killed process %d (%s): by session\n",
3030 task_pid_nr(p
), p
->comm
);
3031 send_sig(SIGKILL
, p
, 1);
3032 } while_each_pid_task(session
, PIDTYPE_SID
, p
);
3034 /* Now kill any processes that happen to have the tty open */
3035 do_each_thread(g
, p
) {
3036 if (p
->signal
->tty
== tty
) {
3037 tty_notice(tty
, "SAK: killed process %d (%s): by controlling tty\n",
3038 task_pid_nr(p
), p
->comm
);
3039 send_sig(SIGKILL
, p
, 1);
3043 i
= iterate_fd(p
->files
, 0, this_tty
, tty
);
3045 tty_notice(tty
, "SAK: killed process %d (%s): by fd#%d\n",
3046 task_pid_nr(p
), p
->comm
, i
- 1);
3047 force_sig(SIGKILL
, p
);
3050 } while_each_thread(g
, p
);
3051 read_unlock(&tasklist_lock
);
3055 static void do_SAK_work(struct work_struct
*work
)
3057 struct tty_struct
*tty
=
3058 container_of(work
, struct tty_struct
, SAK_work
);
3063 * The tq handling here is a little racy - tty->SAK_work may already be queued.
3064 * Fortunately we don't need to worry, because if ->SAK_work is already queued,
3065 * the values which we write to it will be identical to the values which it
3066 * already has. --akpm
3068 void do_SAK(struct tty_struct
*tty
)
3072 schedule_work(&tty
->SAK_work
);
3075 EXPORT_SYMBOL(do_SAK
);
3077 static int dev_match_devt(struct device
*dev
, const void *data
)
3079 const dev_t
*devt
= data
;
3080 return dev
->devt
== *devt
;
3083 /* Must put_device() after it's unused! */
3084 static struct device
*tty_get_device(struct tty_struct
*tty
)
3086 dev_t devt
= tty_devnum(tty
);
3087 return class_find_device(tty_class
, NULL
, &devt
, dev_match_devt
);
3094 * This subroutine allocates and initializes a tty structure.
3096 * Locking: none - tty in question is not exposed at this point
3099 struct tty_struct
*alloc_tty_struct(struct tty_driver
*driver
, int idx
)
3101 struct tty_struct
*tty
;
3103 tty
= kzalloc(sizeof(*tty
), GFP_KERNEL
);
3107 kref_init(&tty
->kref
);
3108 tty
->magic
= TTY_MAGIC
;
3109 tty_ldisc_init(tty
);
3110 tty
->session
= NULL
;
3112 mutex_init(&tty
->legacy_mutex
);
3113 mutex_init(&tty
->throttle_mutex
);
3114 init_rwsem(&tty
->termios_rwsem
);
3115 mutex_init(&tty
->winsize_mutex
);
3116 init_ldsem(&tty
->ldisc_sem
);
3117 init_waitqueue_head(&tty
->write_wait
);
3118 init_waitqueue_head(&tty
->read_wait
);
3119 INIT_WORK(&tty
->hangup_work
, do_tty_hangup
);
3120 mutex_init(&tty
->atomic_write_lock
);
3121 spin_lock_init(&tty
->ctrl_lock
);
3122 spin_lock_init(&tty
->flow_lock
);
3123 INIT_LIST_HEAD(&tty
->tty_files
);
3124 INIT_WORK(&tty
->SAK_work
, do_SAK_work
);
3126 tty
->driver
= driver
;
3127 tty
->ops
= driver
->ops
;
3129 tty_line_name(driver
, idx
, tty
->name
);
3130 tty
->dev
= tty_get_device(tty
);
3136 * deinitialize_tty_struct
3137 * @tty: tty to deinitialize
3139 * This subroutine deinitializes a tty structure that has been newly
3140 * allocated but tty_release cannot be called on that yet.
3142 * Locking: none - tty in question must not be exposed at this point
3144 void deinitialize_tty_struct(struct tty_struct
*tty
)
3146 tty_ldisc_deinit(tty
);
3150 * tty_put_char - write one character to a tty
3154 * Write one byte to the tty using the provided put_char method
3155 * if present. Returns the number of characters successfully output.
3157 * Note: the specific put_char operation in the driver layer may go
3158 * away soon. Don't call it directly, use this method
3161 int tty_put_char(struct tty_struct
*tty
, unsigned char ch
)
3163 if (tty
->ops
->put_char
)
3164 return tty
->ops
->put_char(tty
, ch
);
3165 return tty
->ops
->write(tty
, &ch
, 1);
3167 EXPORT_SYMBOL_GPL(tty_put_char
);
3169 struct class *tty_class
;
3171 static int tty_cdev_add(struct tty_driver
*driver
, dev_t dev
,
3172 unsigned int index
, unsigned int count
)
3176 /* init here, since reused cdevs cause crashes */
3177 driver
->cdevs
[index
] = cdev_alloc();
3178 if (!driver
->cdevs
[index
])
3180 driver
->cdevs
[index
]->ops
= &tty_fops
;
3181 driver
->cdevs
[index
]->owner
= driver
->owner
;
3182 err
= cdev_add(driver
->cdevs
[index
], dev
, count
);
3184 kobject_put(&driver
->cdevs
[index
]->kobj
);
3189 * tty_register_device - register a tty device
3190 * @driver: the tty driver that describes the tty device
3191 * @index: the index in the tty driver for this tty device
3192 * @device: a struct device that is associated with this tty device.
3193 * This field is optional, if there is no known struct device
3194 * for this tty device it can be set to NULL safely.
3196 * Returns a pointer to the struct device for this tty device
3197 * (or ERR_PTR(-EFOO) on error).
3199 * This call is required to be made to register an individual tty device
3200 * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If
3201 * that bit is not set, this function should not be called by a tty
3207 struct device
*tty_register_device(struct tty_driver
*driver
, unsigned index
,
3208 struct device
*device
)
3210 return tty_register_device_attr(driver
, index
, device
, NULL
, NULL
);
3212 EXPORT_SYMBOL(tty_register_device
);
3214 static void tty_device_create_release(struct device
*dev
)
3216 pr_debug("device: '%s': %s\n", dev_name(dev
), __func__
);
3221 * tty_register_device_attr - register a tty device
3222 * @driver: the tty driver that describes the tty device
3223 * @index: the index in the tty driver for this tty device
3224 * @device: a struct device that is associated with this tty device.
3225 * This field is optional, if there is no known struct device
3226 * for this tty device it can be set to NULL safely.
3227 * @drvdata: Driver data to be set to device.
3228 * @attr_grp: Attribute group to be set on device.
3230 * Returns a pointer to the struct device for this tty device
3231 * (or ERR_PTR(-EFOO) on error).
3233 * This call is required to be made to register an individual tty device
3234 * if the tty driver's flags have the TTY_DRIVER_DYNAMIC_DEV bit set. If
3235 * that bit is not set, this function should not be called by a tty
3240 struct device
*tty_register_device_attr(struct tty_driver
*driver
,
3241 unsigned index
, struct device
*device
,
3243 const struct attribute_group
**attr_grp
)
3246 dev_t devt
= MKDEV(driver
->major
, driver
->minor_start
) + index
;
3247 struct device
*dev
= NULL
;
3248 int retval
= -ENODEV
;
3251 if (index
>= driver
->num
) {
3252 printk(KERN_ERR
"Attempt to register invalid tty line number "
3254 return ERR_PTR(-EINVAL
);
3257 if (driver
->type
== TTY_DRIVER_TYPE_PTY
)
3258 pty_line_name(driver
, index
, name
);
3260 tty_line_name(driver
, index
, name
);
3262 if (!(driver
->flags
& TTY_DRIVER_DYNAMIC_ALLOC
)) {
3263 retval
= tty_cdev_add(driver
, devt
, index
, 1);
3269 dev
= kzalloc(sizeof(*dev
), GFP_KERNEL
);
3276 dev
->class = tty_class
;
3277 dev
->parent
= device
;
3278 dev
->release
= tty_device_create_release
;
3279 dev_set_name(dev
, "%s", name
);
3280 dev
->groups
= attr_grp
;
3281 dev_set_drvdata(dev
, drvdata
);
3283 retval
= device_register(dev
);
3292 cdev_del(driver
->cdevs
[index
]);
3293 driver
->cdevs
[index
] = NULL
;
3295 return ERR_PTR(retval
);
3297 EXPORT_SYMBOL_GPL(tty_register_device_attr
);
3300 * tty_unregister_device - unregister a tty device
3301 * @driver: the tty driver that describes the tty device
3302 * @index: the index in the tty driver for this tty device
3304 * If a tty device is registered with a call to tty_register_device() then
3305 * this function must be called when the tty device is gone.
3310 void tty_unregister_device(struct tty_driver
*driver
, unsigned index
)
3312 device_destroy(tty_class
,
3313 MKDEV(driver
->major
, driver
->minor_start
) + index
);
3314 if (!(driver
->flags
& TTY_DRIVER_DYNAMIC_ALLOC
)) {
3315 cdev_del(driver
->cdevs
[index
]);
3316 driver
->cdevs
[index
] = NULL
;
3319 EXPORT_SYMBOL(tty_unregister_device
);
3322 * __tty_alloc_driver -- allocate tty driver
3323 * @lines: count of lines this driver can handle at most
3324 * @owner: module which is repsonsible for this driver
3325 * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags
3327 * This should not be called directly, some of the provided macros should be
3328 * used instead. Use IS_ERR and friends on @retval.
3330 struct tty_driver
*__tty_alloc_driver(unsigned int lines
, struct module
*owner
,
3331 unsigned long flags
)
3333 struct tty_driver
*driver
;
3334 unsigned int cdevs
= 1;
3337 if (!lines
|| (flags
& TTY_DRIVER_UNNUMBERED_NODE
&& lines
> 1))
3338 return ERR_PTR(-EINVAL
);
3340 driver
= kzalloc(sizeof(struct tty_driver
), GFP_KERNEL
);
3342 return ERR_PTR(-ENOMEM
);
3344 kref_init(&driver
->kref
);
3345 driver
->magic
= TTY_DRIVER_MAGIC
;
3346 driver
->num
= lines
;
3347 driver
->owner
= owner
;
3348 driver
->flags
= flags
;
3350 if (!(flags
& TTY_DRIVER_DEVPTS_MEM
)) {
3351 driver
->ttys
= kcalloc(lines
, sizeof(*driver
->ttys
),
3353 driver
->termios
= kcalloc(lines
, sizeof(*driver
->termios
),
3355 if (!driver
->ttys
|| !driver
->termios
) {
3361 if (!(flags
& TTY_DRIVER_DYNAMIC_ALLOC
)) {
3362 driver
->ports
= kcalloc(lines
, sizeof(*driver
->ports
),
3364 if (!driver
->ports
) {
3371 driver
->cdevs
= kcalloc(cdevs
, sizeof(*driver
->cdevs
), GFP_KERNEL
);
3372 if (!driver
->cdevs
) {
3379 kfree(driver
->ports
);
3380 kfree(driver
->ttys
);
3381 kfree(driver
->termios
);
3382 kfree(driver
->cdevs
);
3384 return ERR_PTR(err
);
3386 EXPORT_SYMBOL(__tty_alloc_driver
);
3388 static void destruct_tty_driver(struct kref
*kref
)
3390 struct tty_driver
*driver
= container_of(kref
, struct tty_driver
, kref
);
3392 struct ktermios
*tp
;
3394 if (driver
->flags
& TTY_DRIVER_INSTALLED
) {
3396 * Free the termios and termios_locked structures because
3397 * we don't want to get memory leaks when modular tty
3398 * drivers are removed from the kernel.
3400 for (i
= 0; i
< driver
->num
; i
++) {
3401 tp
= driver
->termios
[i
];
3403 driver
->termios
[i
] = NULL
;
3406 if (!(driver
->flags
& TTY_DRIVER_DYNAMIC_DEV
))
3407 tty_unregister_device(driver
, i
);
3409 proc_tty_unregister_driver(driver
);
3410 if (driver
->flags
& TTY_DRIVER_DYNAMIC_ALLOC
)
3411 cdev_del(driver
->cdevs
[0]);
3413 kfree(driver
->cdevs
);
3414 kfree(driver
->ports
);
3415 kfree(driver
->termios
);
3416 kfree(driver
->ttys
);
3420 void tty_driver_kref_put(struct tty_driver
*driver
)
3422 kref_put(&driver
->kref
, destruct_tty_driver
);
3424 EXPORT_SYMBOL(tty_driver_kref_put
);
3426 void tty_set_operations(struct tty_driver
*driver
,
3427 const struct tty_operations
*op
)
3431 EXPORT_SYMBOL(tty_set_operations
);
3433 void put_tty_driver(struct tty_driver
*d
)
3435 tty_driver_kref_put(d
);
3437 EXPORT_SYMBOL(put_tty_driver
);
3440 * Called by a tty driver to register itself.
3442 int tty_register_driver(struct tty_driver
*driver
)
3449 if (!driver
->major
) {
3450 error
= alloc_chrdev_region(&dev
, driver
->minor_start
,
3451 driver
->num
, driver
->name
);
3453 driver
->major
= MAJOR(dev
);
3454 driver
->minor_start
= MINOR(dev
);
3457 dev
= MKDEV(driver
->major
, driver
->minor_start
);
3458 error
= register_chrdev_region(dev
, driver
->num
, driver
->name
);
3463 if (driver
->flags
& TTY_DRIVER_DYNAMIC_ALLOC
) {
3464 error
= tty_cdev_add(driver
, dev
, 0, driver
->num
);
3466 goto err_unreg_char
;
3469 mutex_lock(&tty_mutex
);
3470 list_add(&driver
->tty_drivers
, &tty_drivers
);
3471 mutex_unlock(&tty_mutex
);
3473 if (!(driver
->flags
& TTY_DRIVER_DYNAMIC_DEV
)) {
3474 for (i
= 0; i
< driver
->num
; i
++) {
3475 d
= tty_register_device(driver
, i
, NULL
);
3478 goto err_unreg_devs
;
3482 proc_tty_register_driver(driver
);
3483 driver
->flags
|= TTY_DRIVER_INSTALLED
;
3487 for (i
--; i
>= 0; i
--)
3488 tty_unregister_device(driver
, i
);
3490 mutex_lock(&tty_mutex
);
3491 list_del(&driver
->tty_drivers
);
3492 mutex_unlock(&tty_mutex
);
3495 unregister_chrdev_region(dev
, driver
->num
);
3499 EXPORT_SYMBOL(tty_register_driver
);
3502 * Called by a tty driver to unregister itself.
3504 int tty_unregister_driver(struct tty_driver
*driver
)
3508 if (driver
->refcount
)
3511 unregister_chrdev_region(MKDEV(driver
->major
, driver
->minor_start
),
3513 mutex_lock(&tty_mutex
);
3514 list_del(&driver
->tty_drivers
);
3515 mutex_unlock(&tty_mutex
);
3519 EXPORT_SYMBOL(tty_unregister_driver
);
3521 dev_t
tty_devnum(struct tty_struct
*tty
)
3523 return MKDEV(tty
->driver
->major
, tty
->driver
->minor_start
) + tty
->index
;
3525 EXPORT_SYMBOL(tty_devnum
);
3527 void tty_default_fops(struct file_operations
*fops
)
3533 * Initialize the console device. This is called *early*, so
3534 * we can't necessarily depend on lots of kernel help here.
3535 * Just do some early initializations, and do the complex setup
3538 void __init
console_init(void)
3542 /* Setup the default TTY line discipline. */
3546 * set up the console device so that later boot sequences can
3547 * inform about problems etc..
3549 call
= __con_initcall_start
;
3550 while (call
< __con_initcall_end
) {
3556 static char *tty_devnode(struct device
*dev
, umode_t
*mode
)
3560 if (dev
->devt
== MKDEV(TTYAUX_MAJOR
, 0) ||
3561 dev
->devt
== MKDEV(TTYAUX_MAJOR
, 2))
3566 static int __init
tty_class_init(void)
3568 tty_class
= class_create(THIS_MODULE
, "tty");
3569 if (IS_ERR(tty_class
))
3570 return PTR_ERR(tty_class
);
3571 tty_class
->devnode
= tty_devnode
;
3575 postcore_initcall(tty_class_init
);
3577 /* 3/2004 jmc: why do these devices exist? */
3578 static struct cdev tty_cdev
, console_cdev
;
3580 static ssize_t
show_cons_active(struct device
*dev
,
3581 struct device_attribute
*attr
, char *buf
)
3583 struct console
*cs
[16];
3589 for_each_console(c
) {
3594 if ((c
->flags
& CON_ENABLED
) == 0)
3597 if (i
>= ARRAY_SIZE(cs
))
3601 int index
= cs
[i
]->index
;
3602 struct tty_driver
*drv
= cs
[i
]->device(cs
[i
], &index
);
3604 /* don't resolve tty0 as some programs depend on it */
3605 if (drv
&& (cs
[i
]->index
> 0 || drv
->major
!= TTY_MAJOR
))
3606 count
+= tty_line_name(drv
, index
, buf
+ count
);
3608 count
+= sprintf(buf
+ count
, "%s%d",
3609 cs
[i
]->name
, cs
[i
]->index
);
3611 count
+= sprintf(buf
+ count
, "%c", i
? ' ':'\n');
3617 static DEVICE_ATTR(active
, S_IRUGO
, show_cons_active
, NULL
);
3619 static struct attribute
*cons_dev_attrs
[] = {
3620 &dev_attr_active
.attr
,
3624 ATTRIBUTE_GROUPS(cons_dev
);
3626 static struct device
*consdev
;
3628 void console_sysfs_notify(void)
3631 sysfs_notify(&consdev
->kobj
, NULL
, "active");
3635 * Ok, now we can initialize the rest of the tty devices and can count
3636 * on memory allocations, interrupts etc..
3638 int __init
tty_init(void)
3640 cdev_init(&tty_cdev
, &tty_fops
);
3641 if (cdev_add(&tty_cdev
, MKDEV(TTYAUX_MAJOR
, 0), 1) ||
3642 register_chrdev_region(MKDEV(TTYAUX_MAJOR
, 0), 1, "/dev/tty") < 0)
3643 panic("Couldn't register /dev/tty driver\n");
3644 device_create(tty_class
, NULL
, MKDEV(TTYAUX_MAJOR
, 0), NULL
, "tty");
3646 cdev_init(&console_cdev
, &console_fops
);
3647 if (cdev_add(&console_cdev
, MKDEV(TTYAUX_MAJOR
, 1), 1) ||
3648 register_chrdev_region(MKDEV(TTYAUX_MAJOR
, 1), 1, "/dev/console") < 0)
3649 panic("Couldn't register /dev/console driver\n");
3650 consdev
= device_create_with_groups(tty_class
, NULL
,
3651 MKDEV(TTYAUX_MAJOR
, 1), NULL
,
3652 cons_dev_groups
, "console");
3653 if (IS_ERR(consdev
))
3657 vty_init(&console_fops
);