#include <linux/proc_fs.h>
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/smp_lock.h>
#include <linux/device.h>
#include <linux/wait.h>
#include <linux/bitops.h>
* N_TTY.
*/
if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
- /* Avoid racing set_ldisc */
+ /* Avoid racing set_ldisc or tty_ldisc_release */
mutex_lock(&tty->ldisc_mutex);
- /* Switch back to N_TTY */
- tty_ldisc_halt(tty);
- tty_ldisc_wait_idle(tty);
- tty_ldisc_reinit(tty);
- /* At this point we have a closed ldisc and we want to
- reopen it. We could defer this to the next open but
- it means auditing a lot of other paths so this is a FIXME */
- WARN_ON(tty_ldisc_open(tty, tty->ldisc));
- tty_ldisc_enable(tty);
+ if (tty->ldisc) { /* Not yet closed */
+ /* Switch back to N_TTY */
+ tty_ldisc_halt(tty);
+ tty_ldisc_wait_idle(tty);
+ tty_ldisc_reinit(tty);
+ /* At this point we have a closed ldisc and we want to
+ reopen it. We could defer this to the next open but
+ it means auditing a lot of other paths so this is
+ a FIXME */
+ WARN_ON(tty_ldisc_open(tty, tty->ldisc));
+ tty_ldisc_enable(tty);
+ }
mutex_unlock(&tty->ldisc_mutex);
tty_reset_termios(tty);
}
tty_ldisc_wait_idle(tty);
+ mutex_lock(&tty->ldisc_mutex);
/*
- * Shutdown the current line discipline, and reset it to N_TTY.
- *
- * FIXME: this MUST get fixed for the new reflocking
+ * Now kill off the ldisc
*/
+ tty_ldisc_close(tty, tty->ldisc);
+ tty_ldisc_put(tty->ldisc);
+ /* Force an oops if we mess this up */
+ tty->ldisc = NULL;
+
+ /* Ensure the next open requests the N_TTY ldisc */
+ tty_set_termios_ldisc(tty, N_TTY);
+ mutex_unlock(&tty->ldisc_mutex);
- tty_ldisc_reinit(tty);
/* This will need doing differently if we need to lock */
if (o_tty)
tty_ldisc_release(o_tty, NULL);
+
+ /* And the memory resources remaining (buffers, termios) will be
+ disposed of when the kref hits zero */
}
/**