1 files changed, 10 insertions, 14 deletions

diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 2ea176b2280e..da9fde850754 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -186,7 +186,6 @@ void free_tty_struct(struct tty_struct *tty)
         if (tty->dev)
                 put_device(tty->dev);
         kfree(tty->write_buf);
-        tty_buffer_free_all(tty);
         tty->magic = 0xDEADDEAD;
         kfree(tty);
 }
@@ -237,7 +236,7 @@ void tty_free_file(struct file *file)
 }
 
 /* Delete file from its tty */
-void tty_del_file(struct file *file)
+static void tty_del_file(struct file *file)
 {
         struct tty_file_private *priv = file->private_data;
 
@@ -555,7 +554,7 @@ EXPORT_SYMBOL_GPL(tty_wakeup);
  *                tasklist_lock to walk task list for hangup event
  *                  ->siglock to protect ->signal/->sighand
  */
-void __tty_hangup(struct tty_struct *tty)
+static void __tty_hangup(struct tty_struct *tty)
 {
         struct file *cons_filp = NULL;
         struct file *filp, *f = NULL;
@@ -1417,6 +1416,8 @@ struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx)
                         "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n",
                         __func__, tty->driver->name);
 
+        tty->port->itty = tty;
+
         /*
          * Structures all installed ... call the ldisc open routines.
          * If we fail here just call release_tty to clean up.  No need
@@ -1552,6 +1553,7 @@ static void release_tty(struct tty_struct *tty, int idx)
                 tty->ops->shutdown(tty);
         tty_free_termios(tty);
         tty_driver_remove_tty(tty->driver, tty);
+        tty->port->itty = NULL;
 
         if (tty->link)
                 tty_kref_put(tty->link);
@@ -1625,7 +1627,6 @@ int tty_release(struct inode *inode, struct file *filp)
         struct tty_struct *tty = file_tty(filp);
         struct tty_struct *o_tty;
         int     pty_master, tty_closing, o_tty_closing, do_sleep;
-        int     devpts;
         int     idx;
         char    buf[64];
 
@@ -1640,7 +1641,6 @@ int tty_release(struct inode *inode, struct file *filp)
         idx = tty->index;
         pty_master = (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
                       tty->driver->subtype == PTY_TYPE_MASTER);
-        devpts = (tty->driver->flags & TTY_DRIVER_DEVPTS_MEM) != 0;
         /* Review: parallel close */
         o_tty = tty->link;
 
@@ -1799,9 +1799,6 @@ int tty_release(struct inode *inode, struct file *filp)
         release_tty(tty, idx);
         mutex_unlock(&tty_mutex);
 
-        /* Make this pty number available for reallocation */
-        if (devpts)
-                devpts_kill_index(inode, idx);
         return 0;
 }
 
@@ -2690,6 +2687,11 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
         case TIOCNXCL:
                 clear_bit(TTY_EXCLUSIVE, &tty->flags);
                 return 0;
+        case TIOCGEXCL:
+        {
+                int excl = test_bit(TTY_EXCLUSIVE, &tty->flags);
+                return put_user(excl, (int __user *)p);
+        }
         case TIOCNOTTY:
                 if (current->signal->tty != tty)
                         return -ENOTTY;
@@ -2937,19 +2939,13 @@ void initialize_tty_struct(struct tty_struct *tty,
         tty_ldisc_init(tty);
         tty->session = NULL;
         tty->pgrp = NULL;
-        tty->overrun_time = jiffies;
-        tty_buffer_init(tty);
         mutex_init(&tty->legacy_mutex);
         mutex_init(&tty->termios_mutex);
         mutex_init(&tty->ldisc_mutex);
         init_waitqueue_head(&tty->write_wait);
         init_waitqueue_head(&tty->read_wait);
         INIT_WORK(&tty->hangup_work, do_tty_hangup);
-        mutex_init(&tty->atomic_read_lock);
         mutex_init(&tty->atomic_write_lock);
-        mutex_init(&tty->output_lock);
-        mutex_init(&tty->echo_lock);
-        spin_lock_init(&tty->read_lock);
         spin_lock_init(&tty->ctrl_lock);
         INIT_LIST_HEAD(&tty->tty_files);
         INIT_WORK(&tty->SAK_work, do_SAK_work);