5 files changed, 65 insertions, 42 deletions

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index 76b27932d229..ec09c1cd4fe9 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -388,7 +388,14 @@ static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
         return -ENOIOCTLCMD;
 }
 
-static const struct tty_operations pty_unix98_ops = {
+static void pty_shutdown(struct tty_struct *tty)
+{
+        /* We have our own method as we don't use the tty index */
+        kfree(tty->termios);
+        kfree(tty->termios_locked);
+}
+
+static const struct tty_operations ptm_unix98_ops = {
         .open = pty_open,
         .close = pty_close,
         .write = pty_write,
@@ -397,10 +404,10 @@ static const struct tty_operations pty_unix98_ops = {
         .chars_in_buffer = pty_chars_in_buffer,
         .unthrottle = pty_unthrottle,
         .set_termios = pty_set_termios,
-        .ioctl = pty_unix98_ioctl
+        .ioctl = pty_unix98_ioctl,
+        .shutdown = pty_shutdown
 };
 
-
 static void __init unix98_pty_init(void)
 {
         ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
@@ -427,7 +434,7 @@ static void __init unix98_pty_init(void)
         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, &pty_unix98_ops);
+        tty_set_operations(ptm_driver, &ptm_unix98_ops);
 
         pts_driver->owner = THIS_MODULE;
         pts_driver->driver_name = "pty_slave";
diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c
index 2e96ce0fddc5..f91704d57a4e 100644
--- a/drivers/char/tty_io.c
+++ b/drivers/char/tty_io.c
@@ -1482,6 +1482,31 @@ release_mem_out:
         goto end_init;
 }
 
+void tty_free_termios(struct tty_struct *tty)
+{
+        struct ktermios *tp;
+        int idx = tty->index;
+        /* Kill this flag and push into drivers for locking etc */
+        if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
+                /* FIXME: Locking on ->termios array */
+                tp = tty->termios;
+                tty->driver->termios[idx] = NULL;
+                kfree(tp);
+
+                tp = tty->termios_locked;
+                tty->driver->termios_locked[idx] = NULL;
+                kfree(tp);
+        }
+}
+EXPORT_SYMBOL(tty_free_termios);
+
+void tty_shutdown(struct tty_struct *tty)
+{
+        tty->driver->ttys[tty->index] = NULL;
+        tty_free_termios(tty);
+}
+EXPORT_SYMBOL(tty_shutdown);
+
 /**
  *      release_one_tty         -       release tty structure memory
  *      @kref: kref of tty we are obliterating
@@ -1499,27 +1524,11 @@ static void release_one_tty(struct kref *kref)
 {
         struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
         struct tty_driver *driver = tty->driver;
-        int devpts = tty->driver->flags & TTY_DRIVER_DEVPTS_MEM;
-        struct ktermios *tp;
-        int idx = tty->index;
-
-        if (!devpts)
-                tty->driver->ttys[idx] = NULL;
-
-        if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
-                /* FIXME: Locking on ->termios array */
-                tp = tty->termios;
-                if (!devpts)
-                        tty->driver->termios[idx] = NULL;
-                kfree(tp);
-
-                tp = tty->termios_locked;
-                if (!devpts)
-                        tty->driver->termios_locked[idx] = NULL;
-                kfree(tp);
-        }
-
 
+        if (tty->ops->shutdown)
+                tty->ops->shutdown(tty);
+        else
+                tty_shutdown(tty);
         tty->magic = 0;
         /* FIXME: locking on tty->driver->refcount */
         tty->driver->refcount--;
diff --git a/drivers/char/vt.c b/drivers/char/vt.c
index ec94521c3118..37a45db5bae0 100644
--- a/drivers/char/vt.c
+++ b/drivers/char/vt.c
@@ -2758,6 +2758,12 @@ static int con_open(struct tty_struct *tty, struct file *filp)
                 ret = vc_allocate(currcons);
                 if (ret == 0) {
                         struct vc_data *vc = vc_cons[currcons].d;
+
+                        /* Still being freed */
+                        if (vc->vc_tty) {
+                                release_console_sem();
+                                return -ERESTARTSYS;
+                        }
                         tty->driver_data = vc;
                         vc->vc_tty = tty;
 
@@ -2787,25 +2793,18 @@ static int con_open(struct tty_struct *tty, struct file *filp)
  */
 static void con_close(struct tty_struct *tty, struct file *filp)
 {
-        mutex_lock(&tty_mutex);
-        acquire_console_sem();
-        if (tty && tty->count == 1) {
-                struct vc_data *vc = tty->driver_data;
+        /* Nothing to do - we defer to shutdown */
+}
 
-                if (vc)
-                        vc->vc_tty = NULL;
-                tty->driver_data = NULL;
-                vcs_remove_sysfs(tty);
-                release_console_sem();
-                mutex_unlock(&tty_mutex);
-                /*
-                 * tty_mutex is released, but we still hold BKL, so there is
-                 * still exclusion against init_dev()
-                 */
-                return;
-        }
+static void con_shutdown(struct tty_struct *tty)
+{
+        struct vc_data *vc = tty->driver_data;
+        BUG_ON(vc == NULL);
+        acquire_console_sem();
+        vc->vc_tty = NULL;
+        vcs_remove_sysfs(tty);
         release_console_sem();
-        mutex_unlock(&tty_mutex);
+        tty_shutdown(tty);
 }
 
 static int default_italic_color    = 2; // green (ASCII)
@@ -2930,6 +2929,7 @@ static const struct tty_operations con_ops = {
         .throttle = con_throttle,
         .unthrottle = con_unthrottle,
         .resize = vt_resize,
+        .shutdown = con_shutdown
 };
 
 int __init vty_init(void)
diff --git a/include/linux/tty.h b/include/linux/tty.h
index e00393a3d1c9..6e39c705b9b6 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -354,7 +354,8 @@ extern void tty_throttle(struct tty_struct *tty);
 extern void tty_unthrottle(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct tty_struct *real_tty,
                                                 struct winsize *ws);
-
+extern void tty_shutdown(struct tty_struct *tty);
+extern void tty_free_termios(struct tty_struct *tty);
 extern int is_current_pgrp_orphaned(void);
 extern struct pid *tty_get_pgrp(struct tty_struct *tty);
 extern int is_ignored(int sig);
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index ac6e58e26b73..2322313a8589 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -21,6 +21,11 @@
  *
  *      Required method.
  *
+ * void (*shutdown)(struct tty_struct * tty);
+ *
+ *      This routine is called when a particular tty device is closed for
+ *      the last time freeing up the resources.
+ *
  * int (*write)(struct tty_struct * tty,
  *               const unsigned char *buf, int count);
  *
@@ -200,6 +205,7 @@ struct tty_driver;
 struct tty_operations {
         int  (*open)(struct tty_struct * tty, struct file * filp);
         void (*close)(struct tty_struct * tty, struct file * filp);
+        void (*shutdown)(struct tty_struct *tty);
         int  (*write)(struct tty_struct * tty,
                       const unsigned char *buf, int count);
         int  (*put_char)(struct tty_struct *tty, unsigned char ch);