tty: Move tty_check_change() helper

Move is_ignored() to drivers/tty/tty_io.c and re-declare in file
scope.
Signed-off-by: NPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/n_tty.c

@@ -1763,12 +1763,6 @@ static int n_tty_receive_buf2(struct tty_struct *tty, const unsigned char *cp,
 	return n_tty_receive_buf_common(tty, cp, fp, count, 1);
 }
 
-int is_ignored(int sig)
-{
-	return (sigismember(&current->blocked, sig) ||
-		current->sighand->action[sig-1].sa.sa_handler == SIG_IGN);
-}
-
 /**
  *	n_tty_set_termios	-	termios data changed
  *	@tty: terminal

drivers/tty/tty_io.c

@@ -381,6 +381,12 @@ struct tty_driver *tty_find_polling_driver(char *name, int *line)
 EXPORT_SYMBOL_GPL(tty_find_polling_driver);
 #endif
 
+static int is_ignored(int sig)
+{
+	return (sigismember(&current->blocked, sig) ||
+		current->sighand->action[sig-1].sa.sa_handler == SIG_IGN);
+}
+
 /**
  *	tty_check_change	-	check for POSIX terminal changes
  *	@tty: tty to check

include/linux/tty.h

@@ -445,7 +445,6 @@ extern int tty_throttle_safe(struct tty_struct *tty);
 extern int tty_unthrottle_safe(struct tty_struct *tty);
 extern int tty_do_resize(struct tty_struct *tty, struct winsize *ws);
 extern int is_current_pgrp_orphaned(void);
-extern int is_ignored(int sig);
 extern void tty_hangup(struct tty_struct *tty);
 extern void tty_vhangup(struct tty_struct *tty);
 extern int tty_hung_up_p(struct file *filp);