[PATCH] USB: convert a bunch of USB semaphores to mutexes

the patch below converts a bunch of semaphores-used-as-mutex in the USB
code to mutexes

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

3 files changed, 21 insertions, 18 deletions

diff --git a/drivers/usb/storage/scsiglue.c b/drivers/usb/storage/scsiglue.c
index 4ef5527028c..5f11e19eaae 100644
--- a/drivers/usb/storage/scsiglue.c
+++ b/drivers/usb/storage/scsiglue.c
@@ -47,6 +47,7 @@
 
 #include <linux/slab.h>
 #include <linux/module.h>
+#include <linux/mutex.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -271,9 +272,9 @@ static int device_reset(struct scsi_cmnd *srb)
 	US_DEBUGP("%s called\n", __FUNCTION__);
 
 	/* lock the device pointers and do the reset */
-	down(&(us->dev_semaphore));
+	mutex_lock(&(us->dev_mutex));
 	result = us->transport_reset(us);
-	up(&(us->dev_semaphore));
+	mutex_unlock(&us->dev_mutex);
 
 	return result < 0 ? FAILED : SUCCESS;
 }
@@ -286,9 +287,9 @@ static int bus_reset(struct scsi_cmnd *srb)
 
 	US_DEBUGP("%s called\n", __FUNCTION__);
 
-	down(&(us->dev_semaphore));
+	mutex_lock(&(us->dev_mutex));
 	result = usb_stor_port_reset(us);
-	up(&(us->dev_semaphore));
+	mutex_unlock(&us->dev_mutex);
 
 	return result < 0 ? FAILED : SUCCESS;
 }
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index dbcf23980ff..dd108634348 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -55,6 +55,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/kthread.h>
+#include <linux/mutex.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -188,7 +189,7 @@ static int storage_suspend(struct usb_interface *iface, pm_message_t message)
 	struct us_data *us = usb_get_intfdata(iface);
 
 	/* Wait until no command is running */
-	down(&us->dev_semaphore);
+	mutex_lock(&us->dev_mutex);
 
 	US_DEBUGP("%s\n", __FUNCTION__);
 	if (us->suspend_resume_hook)
@@ -198,7 +199,7 @@ static int storage_suspend(struct usb_interface *iface, pm_message_t message)
 	/* When runtime PM is working, we'll set a flag to indicate
 	 * whether we should autoresume when a SCSI request arrives. */
 
-	up(&us->dev_semaphore);
+	mutex_unlock(&us->dev_mutex);
 	return 0;
 }
 
@@ -206,14 +207,14 @@ static int storage_resume(struct usb_interface *iface)
 {
 	struct us_data *us = usb_get_intfdata(iface);
 
-	down(&us->dev_semaphore);
+	mutex_lock(&us->dev_mutex);
 
 	US_DEBUGP("%s\n", __FUNCTION__);
 	if (us->suspend_resume_hook)
 		(us->suspend_resume_hook)(us, US_RESUME);
 	iface->dev.power.power_state.event = PM_EVENT_ON;
 
-	up(&us->dev_semaphore);
+	mutex_unlock(&us->dev_mutex);
 	return 0;
 }
 
@@ -276,12 +277,12 @@ static int usb_stor_control_thread(void * __us)
 		US_DEBUGP("*** thread awakened.\n");
 
 		/* lock the device pointers */
-		down(&(us->dev_semaphore));
+		mutex_lock(&(us->dev_mutex));
 
 		/* if the device has disconnected, we are free to exit */
 		if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
 			US_DEBUGP("-- exiting\n");
-			up(&(us->dev_semaphore));
+			mutex_unlock(&us->dev_mutex);
 			break;
 		}
 
@@ -370,7 +371,7 @@ SkipForAbort:
 		scsi_unlock(host);
 
 		/* unlock the device pointers */
-		up(&(us->dev_semaphore));
+		mutex_unlock(&us->dev_mutex);
 	} /* for (;;) */
 
 	scsi_host_put(host);
@@ -815,8 +816,8 @@ static void quiesce_and_remove_host(struct us_data *us)
 	 * The thread will exit when it sees the DISCONNECTING flag. */
 
 	/* Wait for the current command to finish, then remove the host */
-	down(&us->dev_semaphore);
-	up(&us->dev_semaphore);
+	mutex_lock(&us->dev_mutex);
+	mutex_unlock(&us->dev_mutex);
 
 	/* queuecommand won't accept any new commands and the control
 	 * thread won't execute a previously-queued command.  If there
@@ -870,9 +871,9 @@ retry:
 		/* For bulk-only devices, determine the max LUN value */
 		if (us->protocol == US_PR_BULK &&
 				!(us->flags & US_FL_SINGLE_LUN)) {
-			down(&us->dev_semaphore);
+			mutex_lock(&us->dev_mutex);
 			us->max_lun = usb_stor_Bulk_max_lun(us);
-			up(&us->dev_semaphore);
+			mutex_unlock(&us->dev_mutex);
 		}
 		scsi_scan_host(us_to_host(us));
 		printk(KERN_DEBUG "usb-storage: device scan complete\n");
@@ -912,7 +913,7 @@ static int storage_probe(struct usb_interface *intf,
 
 	us = host_to_us(host);
 	memset(us, 0, sizeof(struct us_data));
-	init_MUTEX(&(us->dev_semaphore));
+	mutex_init(&(us->dev_mutex));
 	init_MUTEX_LOCKED(&(us->sema));
 	init_completion(&(us->notify));
 	init_waitqueue_head(&us->delay_wait);
diff --git a/drivers/usb/storage/usb.h b/drivers/usb/storage/usb.h
index 7259fd1f6b0..009fb0953a5 100644
--- a/drivers/usb/storage/usb.h
+++ b/drivers/usb/storage/usb.h
@@ -49,6 +49,7 @@
 #include <linux/blkdev.h>
 #include <linux/smp_lock.h>
 #include <linux/completion.h>
+#include <linux/mutex.h>
 #include <scsi/scsi_host.h>
 
 struct us_data;
@@ -103,9 +104,9 @@ typedef void (*pm_hook)(struct us_data *, int);	/* power management hook */
 struct us_data {
 	/* The device we're working with
 	 * It's important to note:
-	 *    (o) you must hold dev_semaphore to change pusb_dev
+	 *    (o) you must hold dev_mutex to change pusb_dev
 	 */
-	struct semaphore	dev_semaphore;	 /* protect pusb_dev */
+	struct mutex		dev_mutex;	 /* protect pusb_dev */
 	struct usb_device	*pusb_dev;	 /* this usb_device */
 	struct usb_interface	*pusb_intf;	 /* this interface */
 	struct us_unusual_dev   *unusual_dev;	 /* device-filter entry     */