1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/char/snsc.c b/drivers/char/snsc.c
index 32b74de18f5f..5816b39ff5a9 100644
--- a/drivers/char/snsc.c
+++ b/drivers/char/snsc.c
@@ -21,7 +21,7 @@
 #include <linux/poll.h>
 #include <linux/module.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
+#include <linux/mutex.h>
 #include <asm/sn/io.h>
 #include <asm/sn/sn_sal.h>
 #include <asm/sn/module.h>
@@ -34,6 +34,7 @@
 #define SCDRV_BUFSZ     2048
 #define SCDRV_TIMEOUT   1000
 
+static DEFINE_MUTEX(scdrv_mutex);
 static irqreturn_t
 scdrv_interrupt(int irq, void *subch_data)
 {
@@ -105,7 +106,7 @@ scdrv_open(struct inode *inode, struct file *file)
         file->private_data = sd;
 
         /* hook this subchannel up to the system controller interrupt */
-        lock_kernel();
+        mutex_lock(&scdrv_mutex);
         rv = request_irq(SGI_UART_VECTOR, scdrv_interrupt,
                          IRQF_SHARED | IRQF_DISABLED,
                          SYSCTL_BASENAME, sd);
@@ -113,10 +114,10 @@ scdrv_open(struct inode *inode, struct file *file)
                 ia64_sn_irtr_close(sd->sd_nasid, sd->sd_subch);
                 kfree(sd);
                 printk("%s: irq request failed (%d)\n", __func__, rv);
-                unlock_kernel();
+                mutex_unlock(&scdrv_mutex);
                 return -EBUSY;
         }
-        unlock_kernel();
+        mutex_unlock(&scdrv_mutex);
         return 0;
 }
 
@@ -357,6 +358,7 @@ static const struct file_operations scdrv_fops = {
         .poll =         scdrv_poll,
         .open =         scdrv_open,
         .release =      scdrv_release,
+        .llseek =       noop_llseek,
 };
 
 static struct class *snsc_class;