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![Alan Cox](/assets/img/avatar_default.png)
Start trying to untangle the remaining BKL mess Updated to fix missing unlock_kernel noted by Dan Carpenter Signed-off-by: Alan "I must be out of my tree" Cox <alan@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
753 lines
19 KiB
C
753 lines
19 KiB
C
/*
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* linux/drivers/char/pty.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* Added support for a Unix98-style ptmx device.
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* -- C. Scott Ananian <cananian@alumni.princeton.edu>, 14-Jan-1998
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*
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* When reading this code see also fs/devpts. In particular note that the
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* driver_data field is used by the devpts side as a binding to the devpts
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* inode.
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*/
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/interrupt.h>
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#include <linux/tty.h>
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#include <linux/tty_flip.h>
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#include <linux/fcntl.h>
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#include <linux/sched.h>
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#include <linux/string.h>
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#include <linux/major.h>
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/smp_lock.h>
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#include <linux/sysctl.h>
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#include <linux/device.h>
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#include <linux/uaccess.h>
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#include <linux/bitops.h>
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#include <linux/devpts_fs.h>
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#include <asm/system.h>
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#ifdef CONFIG_UNIX98_PTYS
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static struct tty_driver *ptm_driver;
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static struct tty_driver *pts_driver;
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#endif
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static void pty_close(struct tty_struct *tty, struct file *filp)
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{
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BUG_ON(!tty);
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if (tty->driver->subtype == PTY_TYPE_MASTER)
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WARN_ON(tty->count > 1);
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else {
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if (tty->count > 2)
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return;
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}
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wake_up_interruptible(&tty->read_wait);
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wake_up_interruptible(&tty->write_wait);
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tty->packet = 0;
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if (!tty->link)
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return;
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tty->link->packet = 0;
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set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
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wake_up_interruptible(&tty->link->read_wait);
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wake_up_interruptible(&tty->link->write_wait);
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if (tty->driver->subtype == PTY_TYPE_MASTER) {
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set_bit(TTY_OTHER_CLOSED, &tty->flags);
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#ifdef CONFIG_UNIX98_PTYS
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if (tty->driver == ptm_driver)
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devpts_pty_kill(tty->link);
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#endif
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tty_vhangup(tty->link);
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}
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}
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/*
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* The unthrottle routine is called by the line discipline to signal
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* that it can receive more characters. For PTY's, the TTY_THROTTLED
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* flag is always set, to force the line discipline to always call the
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* unthrottle routine when there are fewer than TTY_THRESHOLD_UNTHROTTLE
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* characters in the queue. This is necessary since each time this
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* happens, we need to wake up any sleeping processes that could be
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* (1) trying to send data to the pty, or (2) waiting in wait_until_sent()
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* for the pty buffer to be drained.
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*/
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static void pty_unthrottle(struct tty_struct *tty)
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{
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tty_wakeup(tty->link);
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set_bit(TTY_THROTTLED, &tty->flags);
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}
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/**
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* pty_space - report space left for writing
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* @to: tty we are writing into
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*
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* The tty buffers allow 64K but we sneak a peak and clip at 8K this
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* allows a lot of overspill room for echo and other fun messes to
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* be handled properly
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*/
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static int pty_space(struct tty_struct *to)
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{
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int n = 8192 - to->buf.memory_used;
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if (n < 0)
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return 0;
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return n;
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}
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/**
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* pty_write - write to a pty
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* @tty: the tty we write from
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* @buf: kernel buffer of data
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* @count: bytes to write
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*
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* Our "hardware" write method. Data is coming from the ldisc which
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* may be in a non sleeping state. We simply throw this at the other
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* end of the link as if we were an IRQ handler receiving stuff for
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* the other side of the pty/tty pair.
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*/
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static int pty_write(struct tty_struct *tty, const unsigned char *buf, int c)
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{
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struct tty_struct *to = tty->link;
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if (tty->stopped)
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return 0;
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if (c > 0) {
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/* Stuff the data into the input queue of the other end */
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c = tty_insert_flip_string(to, buf, c);
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/* And shovel */
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if (c) {
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tty_flip_buffer_push(to);
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tty_wakeup(tty);
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}
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}
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return c;
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}
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/**
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* pty_write_room - write space
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* @tty: tty we are writing from
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*
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* Report how many bytes the ldisc can send into the queue for
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* the other device.
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*/
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static int pty_write_room(struct tty_struct *tty)
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{
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if (tty->stopped)
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return 0;
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return pty_space(tty->link);
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}
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/**
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* pty_chars_in_buffer - characters currently in our tx queue
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* @tty: our tty
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*
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* Report how much we have in the transmit queue. As everything is
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* instantly at the other end this is easy to implement.
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*/
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static int pty_chars_in_buffer(struct tty_struct *tty)
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{
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return 0;
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}
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/* Set the lock flag on a pty */
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static int pty_set_lock(struct tty_struct *tty, int __user *arg)
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{
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int val;
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if (get_user(val, arg))
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return -EFAULT;
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if (val)
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set_bit(TTY_PTY_LOCK, &tty->flags);
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else
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clear_bit(TTY_PTY_LOCK, &tty->flags);
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return 0;
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}
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static void pty_flush_buffer(struct tty_struct *tty)
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{
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struct tty_struct *to = tty->link;
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unsigned long flags;
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if (!to)
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return;
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/* tty_buffer_flush(to); FIXME */
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if (to->packet) {
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spin_lock_irqsave(&tty->ctrl_lock, flags);
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tty->ctrl_status |= TIOCPKT_FLUSHWRITE;
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wake_up_interruptible(&to->read_wait);
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spin_unlock_irqrestore(&tty->ctrl_lock, flags);
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}
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}
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static int pty_open(struct tty_struct *tty, struct file *filp)
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{
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int retval = -ENODEV;
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if (!tty || !tty->link)
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goto out;
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retval = -EIO;
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if (test_bit(TTY_OTHER_CLOSED, &tty->flags))
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goto out;
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if (test_bit(TTY_PTY_LOCK, &tty->link->flags))
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goto out;
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if (tty->link->count != 1)
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goto out;
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clear_bit(TTY_OTHER_CLOSED, &tty->link->flags);
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set_bit(TTY_THROTTLED, &tty->flags);
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retval = 0;
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out:
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return retval;
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}
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static void pty_set_termios(struct tty_struct *tty,
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struct ktermios *old_termios)
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{
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tty->termios->c_cflag &= ~(CSIZE | PARENB);
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tty->termios->c_cflag |= (CS8 | CREAD);
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}
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/**
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* pty_do_resize - resize event
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* @tty: tty being resized
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* @ws: window size being set.
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*
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* Update the termios variables and send the neccessary signals to
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* peform a terminal resize correctly
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*/
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int pty_resize(struct tty_struct *tty, struct winsize *ws)
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{
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struct pid *pgrp, *rpgrp;
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unsigned long flags;
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struct tty_struct *pty = tty->link;
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/* For a PTY we need to lock the tty side */
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mutex_lock(&tty->termios_mutex);
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if (!memcmp(ws, &tty->winsize, sizeof(*ws)))
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goto done;
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/* Get the PID values and reference them so we can
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avoid holding the tty ctrl lock while sending signals.
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We need to lock these individually however. */
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spin_lock_irqsave(&tty->ctrl_lock, flags);
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pgrp = get_pid(tty->pgrp);
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spin_unlock_irqrestore(&tty->ctrl_lock, flags);
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spin_lock_irqsave(&pty->ctrl_lock, flags);
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rpgrp = get_pid(pty->pgrp);
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spin_unlock_irqrestore(&pty->ctrl_lock, flags);
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if (pgrp)
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kill_pgrp(pgrp, SIGWINCH, 1);
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if (rpgrp != pgrp && rpgrp)
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kill_pgrp(rpgrp, SIGWINCH, 1);
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put_pid(pgrp);
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put_pid(rpgrp);
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tty->winsize = *ws;
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pty->winsize = *ws; /* Never used so will go away soon */
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done:
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mutex_unlock(&tty->termios_mutex);
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return 0;
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}
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/* Traditional BSD devices */
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#ifdef CONFIG_LEGACY_PTYS
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static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
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{
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struct tty_struct *o_tty;
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int idx = tty->index;
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int retval;
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o_tty = alloc_tty_struct();
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if (!o_tty)
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return -ENOMEM;
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if (!try_module_get(driver->other->owner)) {
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/* This cannot in fact currently happen */
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free_tty_struct(o_tty);
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return -ENOMEM;
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}
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initialize_tty_struct(o_tty, driver->other, idx);
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/* We always use new tty termios data so we can do this
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the easy way .. */
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retval = tty_init_termios(tty);
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if (retval)
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goto free_mem_out;
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retval = tty_init_termios(o_tty);
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if (retval) {
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tty_free_termios(tty);
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goto free_mem_out;
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}
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/*
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* Everything allocated ... set up the o_tty structure.
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*/
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driver->other->ttys[idx] = o_tty;
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tty_driver_kref_get(driver->other);
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if (driver->subtype == PTY_TYPE_MASTER)
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o_tty->count++;
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/* Establish the links in both directions */
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tty->link = o_tty;
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o_tty->link = tty;
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tty_driver_kref_get(driver);
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tty->count++;
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driver->ttys[idx] = tty;
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return 0;
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free_mem_out:
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module_put(o_tty->driver->owner);
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free_tty_struct(o_tty);
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return -ENOMEM;
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}
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static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
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unsigned int cmd, unsigned long arg)
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{
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switch (cmd) {
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case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
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return pty_set_lock(tty, (int __user *) arg);
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}
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return -ENOIOCTLCMD;
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}
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static int legacy_count = CONFIG_LEGACY_PTY_COUNT;
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module_param(legacy_count, int, 0);
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/*
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* The master side of a pty can do TIOCSPTLCK and thus
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* has pty_bsd_ioctl.
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*/
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static const struct tty_operations master_pty_ops_bsd = {
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.install = pty_install,
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.open = pty_open,
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.close = pty_close,
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.write = pty_write,
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.write_room = pty_write_room,
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.flush_buffer = pty_flush_buffer,
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.chars_in_buffer = pty_chars_in_buffer,
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.unthrottle = pty_unthrottle,
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.set_termios = pty_set_termios,
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.ioctl = pty_bsd_ioctl,
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.resize = pty_resize
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};
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static const struct tty_operations slave_pty_ops_bsd = {
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.install = pty_install,
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.open = pty_open,
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.close = pty_close,
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.write = pty_write,
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.write_room = pty_write_room,
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.flush_buffer = pty_flush_buffer,
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.chars_in_buffer = pty_chars_in_buffer,
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.unthrottle = pty_unthrottle,
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.set_termios = pty_set_termios,
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.resize = pty_resize
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};
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static void __init legacy_pty_init(void)
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{
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struct tty_driver *pty_driver, *pty_slave_driver;
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if (legacy_count <= 0)
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return;
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pty_driver = alloc_tty_driver(legacy_count);
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if (!pty_driver)
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panic("Couldn't allocate pty driver");
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pty_slave_driver = alloc_tty_driver(legacy_count);
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if (!pty_slave_driver)
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panic("Couldn't allocate pty slave driver");
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pty_driver->owner = THIS_MODULE;
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pty_driver->driver_name = "pty_master";
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pty_driver->name = "pty";
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pty_driver->major = PTY_MASTER_MAJOR;
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pty_driver->minor_start = 0;
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pty_driver->type = TTY_DRIVER_TYPE_PTY;
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pty_driver->subtype = PTY_TYPE_MASTER;
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pty_driver->init_termios = tty_std_termios;
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pty_driver->init_termios.c_iflag = 0;
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pty_driver->init_termios.c_oflag = 0;
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pty_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
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pty_driver->init_termios.c_lflag = 0;
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pty_driver->init_termios.c_ispeed = 38400;
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pty_driver->init_termios.c_ospeed = 38400;
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pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
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pty_driver->other = pty_slave_driver;
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tty_set_operations(pty_driver, &master_pty_ops_bsd);
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pty_slave_driver->owner = THIS_MODULE;
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pty_slave_driver->driver_name = "pty_slave";
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pty_slave_driver->name = "ttyp";
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pty_slave_driver->major = PTY_SLAVE_MAJOR;
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pty_slave_driver->minor_start = 0;
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pty_slave_driver->type = TTY_DRIVER_TYPE_PTY;
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pty_slave_driver->subtype = PTY_TYPE_SLAVE;
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pty_slave_driver->init_termios = tty_std_termios;
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pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
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pty_slave_driver->init_termios.c_ispeed = 38400;
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pty_slave_driver->init_termios.c_ospeed = 38400;
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pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
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TTY_DRIVER_REAL_RAW;
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pty_slave_driver->other = pty_driver;
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tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
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if (tty_register_driver(pty_driver))
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panic("Couldn't register pty driver");
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if (tty_register_driver(pty_slave_driver))
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panic("Couldn't register pty slave driver");
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}
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#else
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static inline void legacy_pty_init(void) { }
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#endif
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/* Unix98 devices */
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#ifdef CONFIG_UNIX98_PTYS
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/*
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* sysctl support for setting limits on the number of Unix98 ptys allocated.
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* Otherwise one can eat up all kernel memory by opening /dev/ptmx repeatedly.
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*/
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int pty_limit = NR_UNIX98_PTY_DEFAULT;
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static int pty_limit_min;
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static int pty_limit_max = NR_UNIX98_PTY_MAX;
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static int pty_count;
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static struct cdev ptmx_cdev;
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static struct ctl_table pty_table[] = {
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{
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.procname = "max",
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.maxlen = sizeof(int),
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.mode = 0644,
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.data = &pty_limit,
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.proc_handler = proc_dointvec_minmax,
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.extra1 = &pty_limit_min,
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.extra2 = &pty_limit_max,
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}, {
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.procname = "nr",
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.maxlen = sizeof(int),
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.mode = 0444,
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.data = &pty_count,
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.proc_handler = proc_dointvec,
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},
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{}
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};
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static struct ctl_table pty_kern_table[] = {
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{
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.procname = "pty",
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.mode = 0555,
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.child = pty_table,
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},
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{}
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};
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static struct ctl_table pty_root_table[] = {
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{
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.procname = "kernel",
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.mode = 0555,
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.child = pty_kern_table,
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},
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{}
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};
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static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
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unsigned int cmd, unsigned long arg)
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{
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switch (cmd) {
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case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
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return pty_set_lock(tty, (int __user *)arg);
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case TIOCGPTN: /* Get PT Number */
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return put_user(tty->index, (unsigned int __user *)arg);
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}
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return -ENOIOCTLCMD;
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}
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/**
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* ptm_unix98_lookup - find a pty master
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* @driver: ptm driver
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* @idx: tty index
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*
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* Look up a pty master device. Called under the tty_mutex for now.
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* This provides our locking.
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*/
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static struct tty_struct *ptm_unix98_lookup(struct tty_driver *driver,
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struct inode *ptm_inode, int idx)
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{
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struct tty_struct *tty = devpts_get_tty(ptm_inode, idx);
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if (tty)
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tty = tty->link;
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return tty;
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}
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|
|
|
/**
|
|
* pts_unix98_lookup - find a pty slave
|
|
* @driver: pts driver
|
|
* @idx: tty index
|
|
*
|
|
* Look up a pty master device. Called under the tty_mutex for now.
|
|
* This provides our locking.
|
|
*/
|
|
|
|
static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
|
|
struct inode *pts_inode, int idx)
|
|
{
|
|
struct tty_struct *tty = devpts_get_tty(pts_inode, idx);
|
|
/* Master must be open before slave */
|
|
if (!tty)
|
|
return ERR_PTR(-EIO);
|
|
return tty;
|
|
}
|
|
|
|
static void pty_unix98_shutdown(struct tty_struct *tty)
|
|
{
|
|
/* We have our own method as we don't use the tty index */
|
|
kfree(tty->termios);
|
|
}
|
|
|
|
/* We have no need to install and remove our tty objects as devpts does all
|
|
the work for us */
|
|
|
|
static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
|
|
{
|
|
struct tty_struct *o_tty;
|
|
int idx = tty->index;
|
|
|
|
o_tty = alloc_tty_struct();
|
|
if (!o_tty)
|
|
return -ENOMEM;
|
|
if (!try_module_get(driver->other->owner)) {
|
|
/* This cannot in fact currently happen */
|
|
free_tty_struct(o_tty);
|
|
return -ENOMEM;
|
|
}
|
|
initialize_tty_struct(o_tty, driver->other, idx);
|
|
|
|
tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
|
|
if (tty->termios == NULL)
|
|
goto free_mem_out;
|
|
*tty->termios = driver->init_termios;
|
|
tty->termios_locked = tty->termios + 1;
|
|
|
|
o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
|
|
if (o_tty->termios == NULL)
|
|
goto free_mem_out;
|
|
*o_tty->termios = driver->other->init_termios;
|
|
o_tty->termios_locked = o_tty->termios + 1;
|
|
|
|
tty_driver_kref_get(driver->other);
|
|
if (driver->subtype == PTY_TYPE_MASTER)
|
|
o_tty->count++;
|
|
/* Establish the links in both directions */
|
|
tty->link = o_tty;
|
|
o_tty->link = tty;
|
|
/*
|
|
* All structures have been allocated, so now we install them.
|
|
* Failures after this point use release_tty to clean up, so
|
|
* there's no need to null out the local pointers.
|
|
*/
|
|
tty_driver_kref_get(driver);
|
|
tty->count++;
|
|
pty_count++;
|
|
return 0;
|
|
free_mem_out:
|
|
kfree(o_tty->termios);
|
|
module_put(o_tty->driver->owner);
|
|
free_tty_struct(o_tty);
|
|
kfree(tty->termios);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
|
|
{
|
|
pty_count--;
|
|
}
|
|
|
|
static const struct tty_operations ptm_unix98_ops = {
|
|
.lookup = ptm_unix98_lookup,
|
|
.install = pty_unix98_install,
|
|
.remove = pty_unix98_remove,
|
|
.open = pty_open,
|
|
.close = pty_close,
|
|
.write = pty_write,
|
|
.write_room = pty_write_room,
|
|
.flush_buffer = pty_flush_buffer,
|
|
.chars_in_buffer = pty_chars_in_buffer,
|
|
.unthrottle = pty_unthrottle,
|
|
.set_termios = pty_set_termios,
|
|
.ioctl = pty_unix98_ioctl,
|
|
.shutdown = pty_unix98_shutdown,
|
|
.resize = pty_resize
|
|
};
|
|
|
|
static const struct tty_operations pty_unix98_ops = {
|
|
.lookup = pts_unix98_lookup,
|
|
.install = pty_unix98_install,
|
|
.remove = pty_unix98_remove,
|
|
.open = pty_open,
|
|
.close = pty_close,
|
|
.write = pty_write,
|
|
.write_room = pty_write_room,
|
|
.flush_buffer = pty_flush_buffer,
|
|
.chars_in_buffer = pty_chars_in_buffer,
|
|
.unthrottle = pty_unthrottle,
|
|
.set_termios = pty_set_termios,
|
|
.shutdown = pty_unix98_shutdown
|
|
};
|
|
|
|
/**
|
|
* ptmx_open - open a unix 98 pty master
|
|
* @inode: inode of device file
|
|
* @filp: file pointer to tty
|
|
*
|
|
* Allocate a unix98 pty master device from the ptmx driver.
|
|
*
|
|
* Locking: tty_mutex protects the init_dev work. tty->count should
|
|
* protect the rest.
|
|
* allocated_ptys_lock handles the list of free pty numbers
|
|
*/
|
|
|
|
static int __ptmx_open(struct inode *inode, struct file *filp)
|
|
{
|
|
struct tty_struct *tty;
|
|
int retval;
|
|
int index;
|
|
|
|
nonseekable_open(inode, filp);
|
|
|
|
/* find a device that is not in use. */
|
|
index = devpts_new_index(inode);
|
|
if (index < 0)
|
|
return index;
|
|
|
|
mutex_lock(&tty_mutex);
|
|
tty = tty_init_dev(ptm_driver, index, 1);
|
|
mutex_unlock(&tty_mutex);
|
|
|
|
if (IS_ERR(tty)) {
|
|
retval = PTR_ERR(tty);
|
|
goto out;
|
|
}
|
|
|
|
set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
|
|
filp->private_data = tty;
|
|
file_move(filp, &tty->tty_files);
|
|
|
|
retval = devpts_pty_new(inode, tty->link);
|
|
if (retval)
|
|
goto out1;
|
|
|
|
retval = ptm_driver->ops->open(tty, filp);
|
|
if (!retval)
|
|
return 0;
|
|
out1:
|
|
tty_release(inode, filp);
|
|
return retval;
|
|
out:
|
|
devpts_kill_index(inode, index);
|
|
return retval;
|
|
}
|
|
|
|
static int ptmx_open(struct inode *inode, struct file *filp)
|
|
{
|
|
int ret;
|
|
|
|
lock_kernel();
|
|
ret = __ptmx_open(inode, filp);
|
|
unlock_kernel();
|
|
return ret;
|
|
}
|
|
|
|
static struct file_operations ptmx_fops;
|
|
|
|
static void __init unix98_pty_init(void)
|
|
{
|
|
ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
|
|
if (!ptm_driver)
|
|
panic("Couldn't allocate Unix98 ptm driver");
|
|
pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
|
|
if (!pts_driver)
|
|
panic("Couldn't allocate Unix98 pts driver");
|
|
|
|
ptm_driver->owner = THIS_MODULE;
|
|
ptm_driver->driver_name = "pty_master";
|
|
ptm_driver->name = "ptm";
|
|
ptm_driver->major = UNIX98_PTY_MASTER_MAJOR;
|
|
ptm_driver->minor_start = 0;
|
|
ptm_driver->type = TTY_DRIVER_TYPE_PTY;
|
|
ptm_driver->subtype = PTY_TYPE_MASTER;
|
|
ptm_driver->init_termios = tty_std_termios;
|
|
ptm_driver->init_termios.c_iflag = 0;
|
|
ptm_driver->init_termios.c_oflag = 0;
|
|
ptm_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
|
|
ptm_driver->init_termios.c_lflag = 0;
|
|
ptm_driver->init_termios.c_ispeed = 38400;
|
|
ptm_driver->init_termios.c_ospeed = 38400;
|
|
ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
|
|
TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
|
|
ptm_driver->other = pts_driver;
|
|
tty_set_operations(ptm_driver, &ptm_unix98_ops);
|
|
|
|
pts_driver->owner = THIS_MODULE;
|
|
pts_driver->driver_name = "pty_slave";
|
|
pts_driver->name = "pts";
|
|
pts_driver->major = UNIX98_PTY_SLAVE_MAJOR;
|
|
pts_driver->minor_start = 0;
|
|
pts_driver->type = TTY_DRIVER_TYPE_PTY;
|
|
pts_driver->subtype = PTY_TYPE_SLAVE;
|
|
pts_driver->init_termios = tty_std_termios;
|
|
pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
|
|
pts_driver->init_termios.c_ispeed = 38400;
|
|
pts_driver->init_termios.c_ospeed = 38400;
|
|
pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
|
|
TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
|
|
pts_driver->other = ptm_driver;
|
|
tty_set_operations(pts_driver, &pty_unix98_ops);
|
|
|
|
if (tty_register_driver(ptm_driver))
|
|
panic("Couldn't register Unix98 ptm driver");
|
|
if (tty_register_driver(pts_driver))
|
|
panic("Couldn't register Unix98 pts driver");
|
|
|
|
register_sysctl_table(pty_root_table);
|
|
|
|
/* Now create the /dev/ptmx special device */
|
|
tty_default_fops(&ptmx_fops);
|
|
ptmx_fops.open = ptmx_open;
|
|
|
|
cdev_init(&ptmx_cdev, &ptmx_fops);
|
|
if (cdev_add(&ptmx_cdev, MKDEV(TTYAUX_MAJOR, 2), 1) ||
|
|
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 2), 1, "/dev/ptmx") < 0)
|
|
panic("Couldn't register /dev/ptmx driver\n");
|
|
device_create(tty_class, NULL, MKDEV(TTYAUX_MAJOR, 2), NULL, "ptmx");
|
|
}
|
|
|
|
#else
|
|
static inline void unix98_pty_init(void) { }
|
|
#endif
|
|
|
|
static int __init pty_init(void)
|
|
{
|
|
legacy_pty_init();
|
|
unix98_pty_init();
|
|
return 0;
|
|
}
|
|
module_init(pty_init);
|