[PATCH] epca: lock_kernel push down

[PATCH] epca: lock_kernel push down

[Alan Cox]

Prepare epca for removing the lock from above. Most of epca is internally
locked so we can trivially push it down to a few bits of code. Drop the TIOCG/SSOFTCAR handling as that is done *properly* with locks by the mid layer.

diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.25-rc2-mm1/drivers/char/epca.c linux-2.6.25-rc2-mm1/drivers/char/epca.c
--- linux.vanilla-2.6.25-rc2-mm1/drivers/char/epca.c	2008-02-19 11:03:00.000000000 +0000
+++ linux-2.6.25-rc2-mm1/drivers/char/epca.c	2008-02-20 11:45:43.000000000 +0000
@@ -2206,21 +2206,6 @@
 		tty_wait_until_sent(tty, 0);
 		digi_send_break(ch, arg ? arg*(HZ/10) : HZ/4);
 		return 0;
-	case TIOCGSOFTCAR:
-		if (put_user(C_CLOCAL(tty)?1:0, (unsigned long __user *)arg))
-			return -EFAULT;
-		return 0;
-	case TIOCSSOFTCAR:
-		{
-			unsigned int value;
-
-			if (get_user(value, (unsigned __user *)argp))
-				return -EFAULT;
-			tty->termios->c_cflag =
-				((tty->termios->c_cflag & ~CLOCAL) |
-				 (value ? CLOCAL : 0));
-			return 0;
-		}
 	case TIOCMODG:
 		mflag = pc_tiocmget(tty, file);
 		if (put_user(mflag, (unsigned long __user *)argp))
@@ -2253,6 +2238,7 @@
 		break;
 	case DIGI_SETAW:
 	case DIGI_SETAF:
+		lock_kernel();
 		if (cmd == DIGI_SETAW) {
 			/* Setup an event to indicate when the transmit buffer empties */
 			spin_lock_irqsave(&epca_lock, flags);
@@ -2264,6 +2250,7 @@
 			if (tty->ldisc.flush_buffer)
 				tty->ldisc.flush_buffer(tty);
 		}
+		unlock_kernel();
 		/* Fall Thru */
 	case DIGI_SETA:
 		if (copy_from_user(&ch->digiext, argp, sizeof(digi_t)))