mutex_lock(&tty_mutex);
/* Search through the tty devices to look for a match */
list_for_each_entry(p, &tty_drivers, tty_drivers) {
- if (strncmp(name, p->name, len) != 0)
+ if (!len || strncmp(name, p->name, len) != 0)
continue;
stp = str;
if (*stp == ',')
static DEFINE_SPINLOCK(redirect_lock);
static struct file *redirect;
+extern void tty_sysctl_init(void);
+
/**
* tty_wakeup - request more data
* @tty: terminal
return;
}
+ /*
+ * Some console devices aren't actually hung up for technical and
+ * historical reasons, which can lead to indefinite interruptible
+ * sleep in n_tty_read(). The following explicitly tells
+ * n_tty_read() to abort readers.
+ */
+ set_bit(TTY_HUPPING, &tty->flags);
+
/* inuse_filps is protected by the single tty lock,
this really needs to change if we want to flush the
workqueue with the lock held */
* from the ldisc side, which is now guaranteed.
*/
set_bit(TTY_HUPPED, &tty->flags);
+ clear_bit(TTY_HUPPING, &tty->flags);
tty_unlock(tty);
if (f)
static int tty_reopen(struct tty_struct *tty)
{
struct tty_driver *driver = tty->driver;
+ struct tty_ldisc *ld;
+ int retval = 0;
if (driver->type == TTY_DRIVER_TYPE_PTY &&
driver->subtype == PTY_TYPE_MASTER)
if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN))
return -EBUSY;
- tty->count++;
+ ld = tty_ldisc_ref_wait(tty);
+ if (ld) {
+ tty_ldisc_deref(ld);
+ } else {
+ retval = tty_ldisc_lock(tty, 5 * HZ);
+ if (retval)
+ return retval;
+
+ if (!tty->ldisc)
+ retval = tty_ldisc_reinit(tty, tty->termios.c_line);
+ tty_ldisc_unlock(tty);
+ }
- if (!tty->ldisc)
- return tty_ldisc_reinit(tty, tty->termios.c_line);
+ if (retval == 0)
+ tty->count++;
- return 0;
+ return retval;
}
/**
"%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n",
__func__, tty->driver->name);
+ retval = tty_ldisc_lock(tty, 5 * HZ);
+ if (retval)
+ goto err_release_lock;
tty->port->itty = tty;
/*
retval = tty_ldisc_setup(tty, tty->link);
if (retval)
goto err_release_tty;
+ tty_ldisc_unlock(tty);
/* Return the tty locked so that it cannot vanish under the caller */
return tty;
/* call the tty release_tty routine to clean out this slot */
err_release_tty:
- tty_unlock(tty);
+ tty_ldisc_unlock(tty);
tty_info_ratelimited(tty, "ldisc open failed (%d), clearing slot %d\n",
retval, idx);
+err_release_lock:
+ tty_unlock(tty);
release_tty(tty, idx);
return ERR_PTR(retval);
}
-static void tty_free_termios(struct tty_struct *tty)
+/**
+ * tty_save_termios() - save tty termios data in driver table
+ * @tty: tty whose termios data to save
+ *
+ * Locking: Caller guarantees serialisation with tty_init_termios().
+ */
+void tty_save_termios(struct tty_struct *tty)
{
struct ktermios *tp;
int idx = tty->index;
}
*tp = tty->termios;
}
+EXPORT_SYMBOL_GPL(tty_save_termios);
/**
* tty_flush_works - flush all works of a tty/pty pair
WARN_ON(!mutex_is_locked(&tty_mutex));
if (tty->ops->shutdown)
tty->ops->shutdown(tty);
- tty_free_termios(tty);
+ tty_save_termios(tty);
tty_driver_remove_tty(tty->driver, tty);
tty->port->itty = NULL;
if (tty->link)
tty->link->port->itty = NULL;
tty_buffer_cancel_work(tty->port);
+ if (tty->link)
+ tty_buffer_cancel_work(tty->link->port);
tty_kref_put(tty->link);
tty_kref_put(tty);
ld = tty_ldisc_ref_wait(tty);
if (!ld)
return -EIO;
- ld->ops->receive_buf(tty, &ch, &mbz, 1);
+ if (ld->ops->receive_buf)
+ ld->ops->receive_buf(tty, &ch, &mbz, 1);
tty_ldisc_deref(ld);
return 0;
}
kref_init(&tty->kref);
tty->magic = TTY_MAGIC;
- tty_ldisc_init(tty);
+ if (tty_ldisc_init(tty)) {
+ kfree(tty);
+ return NULL;
+ }
tty->session = NULL;
tty->pgrp = NULL;
mutex_init(&tty->legacy_mutex);
*/
int __init tty_init(void)
{
+ tty_sysctl_init();
cdev_init(&tty_cdev, &tty_fops);
if (cdev_add(&tty_cdev, MKDEV(TTYAUX_MAJOR, 0), 1) ||
register_chrdev_region(MKDEV(TTYAUX_MAJOR, 0), 1, "/dev/tty") < 0)