TTY: n_tty, add ldisc data to n_tty

All n_tty related members from tty_struct will be moved here.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c
index 3ebab0cfceb254eb53c9301601bf75db3c3dfb13..3d1594e10d0062e82765e6eb84b36bb7162957c3 100644 (file)
--- a/drivers/tty/n_tty.c
+++ b/drivers/tty/n_tty.c
@@ -73,6 +73,10 @@
 #define ECHO_OP_SET_CANON_COL 0x81
 #define ECHO_OP_ERASE_TAB 0x82
 
+struct n_tty_data {
+       char dummy;
+};
+
 static inline int tty_put_user(struct tty_struct *tty, unsigned char x,
                               unsigned char __user *ptr)
 {
@@ -1556,11 +1560,15 @@ static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 
 static void n_tty_close(struct tty_struct *tty)
 {
+       struct n_tty_data *ldata = tty->disc_data;
+
        n_tty_flush_buffer(tty);
        kfree(tty->read_buf);
        kfree(tty->echo_buf);
+       kfree(ldata);
        tty->read_buf = NULL;
        tty->echo_buf = NULL;
+       tty->disc_data = NULL;
 }
 
 /**
@@ -1575,23 +1583,32 @@ static void n_tty_close(struct tty_struct *tty)
 
 static int n_tty_open(struct tty_struct *tty)
 {
+       struct n_tty_data *ldata;
+
+       ldata = kzalloc(sizeof(*ldata), GFP_KERNEL);
+       if (!ldata)
+               goto err;
+
        /* These are ugly. Currently a malloc failure here can panic */
        tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
        tty->echo_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL);
        if (!tty->read_buf || !tty->echo_buf)
                goto err_free_bufs;
 
+       tty->disc_data = ldata;
        reset_buffer_flags(tty);
        tty_unthrottle(tty);
        tty->column = 0;
        n_tty_set_termios(tty, NULL);
        tty->minimum_to_wake = 1;
        tty->closing = 0;
+
        return 0;
 err_free_bufs:
        kfree(tty->read_buf);
        kfree(tty->echo_buf);
-
+       kfree(ldata);
+err:
        return -ENOMEM;
 }