riscom8: kill use of lock_kernel

The riscom8 board uses lock_kernel to protect bits of the port setting
ioctl logic. We can use the port mutex for this as the logic is internal
and will also lock set versus open (a locking property that has been lost
somewhere along the way)

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/riscom8.c b/drivers/char/riscom8.c
index b02332a5412f781c2631046cb32e12866be64c47..af4de1fe84454eca88f3921cfe786282e14fdf37 100644 (file)
--- a/drivers/char/riscom8.c
+++ b/drivers/char/riscom8.c
@@ -47,7 +47,6 @@
 #include <linux/init.h>
 #include <linux/delay.h>
 #include <linux/tty_flip.h>
-#include <linux/smp_lock.h>
 #include <linux/spinlock.h>
 #include <linux/device.h>
 
@@ -1184,6 +1183,7 @@ static int rc_set_serial_info(struct tty_struct *tty, struct riscom_port *port,
        if (copy_from_user(&tmp, newinfo, sizeof(tmp)))
                return -EFAULT;
 
+       mutex_lock(&port->port.mutex);
        change_speed = ((port->port.flags & ASYNC_SPD_MASK) !=
                        (tmp.flags & ASYNC_SPD_MASK));
 
@@ -1191,8 +1191,10 @@ static int rc_set_serial_info(struct tty_struct *tty, struct riscom_port *port,
                if ((tmp.close_delay != port->port.close_delay) ||
                    (tmp.closing_wait != port->port.closing_wait) ||
                    ((tmp.flags & ~ASYNC_USR_MASK) !=
-                    (port->port.flags & ~ASYNC_USR_MASK)))
+                    (port->port.flags & ~ASYNC_USR_MASK))) {
+                       mutex_unlock(&port->port.mutex);
                        return -EPERM;
+               }
                port->port.flags = ((port->port.flags & ~ASYNC_USR_MASK) |
                               (tmp.flags & ASYNC_USR_MASK));
        } else  {
@@ -1208,6 +1210,7 @@ static int rc_set_serial_info(struct tty_struct *tty, struct riscom_port *port,
                rc_change_speed(tty, bp, port);
                spin_unlock_irqrestore(&riscom_lock, flags);
        }
+       mutex_unlock(&port->port.mutex);
        return 0;
 }
 
@@ -1220,12 +1223,15 @@ static int rc_get_serial_info(struct riscom_port *port,
        memset(&tmp, 0, sizeof(tmp));
        tmp.type = PORT_CIRRUS;
        tmp.line = port - rc_port;
+
+       mutex_lock(&port->port.mutex);
        tmp.port = bp->base;
        tmp.irq  = bp->irq;
        tmp.flags = port->port.flags;
        tmp.baud_base = (RC_OSCFREQ + CD180_TPC/2) / CD180_TPC;
        tmp.close_delay = port->port.close_delay * HZ/100;
        tmp.closing_wait = port->port.closing_wait * HZ/100;
+       mutex_unlock(&port->port.mutex);
        tmp.xmit_fifo_size = CD180_NFIFO;
        return copy_to_user(retinfo, &tmp, sizeof(tmp)) ? -EFAULT : 0;
 }
@@ -1242,14 +1248,10 @@ static int rc_ioctl(struct tty_struct *tty, struct file *filp,
 
        switch (cmd) {
        case TIOCGSERIAL:
-               lock_kernel();
                retval = rc_get_serial_info(port, argp);
-               unlock_kernel();
                break;
        case TIOCSSERIAL:
-               lock_kernel();
                retval = rc_set_serial_info(tty, port, argp);
-               unlock_kernel();
                break;
        default:
                retval = -ENOIOCTLCMD;