rocket: kill BKL

We can use the port mutex for this and also for the hangup path so removing
the problematic use of the hangup mutex in this driver. Fix up the locking
on the various port flags while we are at it.

Ultimately this driver needs to be using tty_port_ helpers which would sort
this out far better.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/char/rocket.c b/drivers/char/rocket.c
index 0e29a23..79c3bc6 100644
--- a/drivers/char/rocket.c
+++ b/drivers/char/rocket.c
@@ -73,7 +73,6 @@
 #include <linux/tty_driver.h>
 #include <linux/tty_flip.h>
 #include <linux/serial.h>
-#include <linux/smp_lock.h>
 #include <linux/string.h>
 #include <linux/fcntl.h>
 #include <linux/ptrace.h>
@@ -1017,6 +1016,7 @@
 	if (tty_port_close_start(port, tty, filp) == 0)
 		return;
 
+	mutex_lock(&port->mutex);
 	cp = &info->channel;
 	/*
 	 * Before we drop DTR, make sure the UART transmitter
@@ -1060,9 +1060,13 @@
 			info->xmit_buf = NULL;
 		}
 	}
+	spin_lock_irq(&port->lock);
 	info->port.flags &= ~(ASYNC_INITIALIZED | ASYNC_CLOSING | ASYNC_NORMAL_ACTIVE);
 	tty->closing = 0;
+	spin_unlock_irq(&port->lock);
+	mutex_unlock(&port->mutex);
 	tty_port_tty_set(port, NULL);
+
 	wake_up_interruptible(&port->close_wait);
 	complete_all(&info->close_wait);
 	atomic_dec(&rp_num_ports_open);
@@ -1210,11 +1214,13 @@
 	if (!retinfo)
 		return -EFAULT;
 	memset(&tmp, 0, sizeof (tmp));
+	mutex_lock(&info->port.mutex);
 	tmp.line = info->line;
 	tmp.flags = info->flags;
 	tmp.close_delay = info->port.close_delay;
 	tmp.closing_wait = info->port.closing_wait;
 	tmp.port = rcktpt_io_addr[(info->line >> 5) & 3];
+	mutex_unlock(&info->port.mutex);
 
 	if (copy_to_user(retinfo, &tmp, sizeof (*retinfo)))
 		return -EFAULT;
@@ -1229,10 +1235,13 @@
 	if (copy_from_user(&new_serial, new_info, sizeof (new_serial)))
 		return -EFAULT;
 
+	mutex_lock(&info->port.mutex);
 	if (!capable(CAP_SYS_ADMIN))
 	{
-		if ((new_serial.flags & ~ROCKET_USR_MASK) != (info->flags & ~ROCKET_USR_MASK))
+		if ((new_serial.flags & ~ROCKET_USR_MASK) != (info->flags & ~ROCKET_USR_MASK)) {
+			mutex_unlock(&info->port.mutex);
 			return -EPERM;
+		}
 		info->flags = ((info->flags & ~ROCKET_USR_MASK) | (new_serial.flags & ROCKET_USR_MASK));
 		configure_r_port(tty, info, NULL);
 		return 0;
@@ -1250,6 +1259,7 @@
 		tty->alt_speed = 230400;
 	if ((info->flags & ROCKET_SPD_MASK) == ROCKET_SPD_WARP)
 		tty->alt_speed = 460800;
+	mutex_unlock(&info->port.mutex);
 
 	configure_r_port(tty, info, NULL);
 	return 0;
@@ -1325,8 +1335,6 @@
 	if (cmd != RCKP_GET_PORTS && rocket_paranoia_check(info, "rp_ioctl"))
 		return -ENXIO;
 
-	lock_kernel();
-
 	switch (cmd) {
 	case RCKP_GET_STRUCT:
 		if (copy_to_user(argp, info, sizeof (struct r_port)))
@@ -1350,7 +1358,6 @@
 	default:
 		ret = -ENOIOCTLCMD;
 	}
-	unlock_kernel();
 	return ret;
 }
 
@@ -1471,7 +1478,6 @@
 	       jiffies);
 	printk(KERN_INFO "cps=%d...\n", info->cps);
 #endif
-	lock_kernel();
 	while (1) {
 		txcnt = sGetTxCnt(cp);
 		if (!txcnt) {
@@ -1499,7 +1505,6 @@
 			break;
 	}
 	__set_current_state(TASK_RUNNING);
-	unlock_kernel();
 #ifdef ROCKET_DEBUG_WAIT_UNTIL_SENT
 	printk(KERN_INFO "txcnt = %d (jiff=%lu)...done\n", txcnt, jiffies);
 #endif
@@ -1512,6 +1517,7 @@
 {
 	CHANNEL_t *cp;
 	struct r_port *info = tty->driver_data;
+	unsigned long flags;
 
 	if (rocket_paranoia_check(info, "rp_hangup"))
 		return;
@@ -1520,11 +1526,15 @@
 	printk(KERN_INFO "rp_hangup of ttyR%d...\n", info->line);
 #endif
 	rp_flush_buffer(tty);
-	if (info->port.flags & ASYNC_CLOSING)
+	spin_lock_irqsave(&info->port.lock, flags);
+	if (info->port.flags & ASYNC_CLOSING) {
+		spin_unlock_irqrestore(&info->port.lock, flags);
 		return;
+	}
 	if (info->port.count)
 		atomic_dec(&rp_num_ports_open);
 	clear_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);
+	spin_unlock_irqrestore(&info->port.lock, flags);
 
 	tty_port_hangup(&info->port);
 
@@ -1535,7 +1545,7 @@
 	sDisCTSFlowCtl(cp);
 	sDisTxSoftFlowCtl(cp);
 	sClrTxXOFF(cp);
-	info->port.flags &= ~ASYNC_INITIALIZED;
+	clear_bit(ASYNCB_INITIALIZED, &info->port.flags);
 
 	wake_up_interruptible(&info->port.open_wait);
 }