TTY: move ldisc data from tty_struct: simple members

Here we start moving all the n_tty related bits from tty_struct to
the newly defined n_tty_data struct in n_tty proper.

In this patch primitive members and bits are moved. The rest will be
done per-partes in the next patches.
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>

drivers/tty/tty_io.c

@@ -2932,7 +2932,6 @@ 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);

include/linux/tty.h

@@ -270,13 +270,8 @@ struct tty_struct {
 	 * historical reasons, this is included in the tty structure.
 	 * Mostly locked by the BKL.
 	 */
-	unsigned int column;
-	unsigned char lnext:1, erasing:1, raw:1, real_raw:1, icanon:1;
 	unsigned char closing:1;
-	unsigned char echo_overrun:1;
 	unsigned short minimum_to_wake;
-	unsigned long overrun_time;
-	int num_overrun;
 	unsigned long process_char_map[256/(8*sizeof(unsigned long))];
 	char *read_buf;
 	int read_head;