1 files changed, 48 insertions, 1 deletions

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index 328e8ac12306..6e148ade7353 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -391,6 +391,41 @@ static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
         return -ENOIOCTLCMD;
 }
 
+/**
+ *      ptm_unix98_lookup       -       find a pty master
+ *      @driver: ptm 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 *ptm_unix98_lookup(struct tty_driver *driver, int idx)
+{
+        struct tty_struct *tty = devpts_get_tty(idx);
+        if (tty)
+                tty = tty->link;
+        return tty;
+}
+
+/**
+ *      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, int idx)
+{
+        struct tty_struct *tty = devpts_get_tty(idx);
+        /* Master must be open before slave */
+        if (!tty)
+                return ERR_PTR(-EIO);
+        return tty;
+}
+
 static void pty_shutdown(struct tty_struct *tty)
 {
         /* We have our own method as we don't use the tty index */
@@ -399,6 +434,7 @@ static void pty_shutdown(struct tty_struct *tty)
 }
 
 static const struct tty_operations ptm_unix98_ops = {
+        .lookup = ptm_unix98_lookup,
         .open = pty_open,
         .close = pty_close,
         .write = pty_write,
@@ -411,6 +447,17 @@ static const struct tty_operations ptm_unix98_ops = {
         .shutdown = pty_shutdown
 };
 
+static const struct tty_operations pty_unix98_ops = {
+        .lookup = pts_unix98_lookup,
+        .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,
+};
 
 /**
  *      ptmx_open               -       open a unix 98 pty master
@@ -517,7 +564,7 @@ static void __init unix98_pty_init(void)
         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_ops);
+        tty_set_operations(pts_driver, &pty_unix98_ops);
         
         if (tty_register_driver(ptm_driver))
                 panic("Couldn't register Unix98 ptm driver");