[SCSI] turn most scsi semaphores into mutexes

the scsi layer is using semaphores in a mutex way, this patch converts
these into using mutexes instead

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index c4aade8..6e4a36a 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -38,6 +38,7 @@
 #include <linux/devfs_fs_kernel.h>
 #include <linux/cdev.h>
 #include <linux/delay.h>
+#include <linux/mutex.h>
 
 #include <asm/uaccess.h>
 #include <asm/dma.h>
@@ -220,7 +221,7 @@
 
 #define to_scsi_tape(obj) container_of(obj, struct scsi_tape, kref)
 
-static DECLARE_MUTEX(st_ref_sem);
+static DEFINE_MUTEX(st_ref_mutex);
 
 
 #include "osst_detect.h"
@@ -237,7 +238,7 @@
 {
 	struct scsi_tape *STp = NULL;
 
-	down(&st_ref_sem);
+	mutex_lock(&st_ref_mutex);
 	write_lock(&st_dev_arr_lock);
 
 	if (dev < st_dev_max && scsi_tapes != NULL)
@@ -259,7 +260,7 @@
 	STp = NULL;
 out:
 	write_unlock(&st_dev_arr_lock);
-	up(&st_ref_sem);
+	mutex_unlock(&st_ref_mutex);
 	return STp;
 }
 
@@ -267,10 +268,10 @@
 {
 	struct scsi_device *sdev = STp->device;
 
-	down(&st_ref_sem);
+	mutex_lock(&st_ref_mutex);
 	kref_put(&STp->kref, scsi_tape_release);
 	scsi_device_put(sdev);
-	up(&st_ref_sem);
+	mutex_unlock(&st_ref_mutex);
 }
 
 struct st_reject_data {
@@ -4141,9 +4142,9 @@
 				}
 			}
 
-			down(&st_ref_sem);
+			mutex_lock(&st_ref_mutex);
 			kref_put(&tpnt->kref, scsi_tape_release);
-			up(&st_ref_sem);
+			mutex_unlock(&st_ref_mutex);
 			return 0;
 		}
 	}
@@ -4156,7 +4157,7 @@
  *      scsi_tape_release - Called to free the Scsi_Tape structure
  *      @kref: pointer to embedded kref
  *
- *      st_ref_sem must be held entering this routine.  Because it is
+ *      st_ref_mutex must be held entering this routine.  Because it is
  *      called on last put, you should always use the scsi_tape_get()
  *      scsi_tape_put() helpers which manipulate the semaphore directly
  *      and never do a direct kref_put().