[media] uvcvideo: Move mutex lock/unlock inside uvc_free_buffers

Callers outside uvc_queue.c should not be forced to lock/unlock the
queue mutex manually. Move the mutex operations inside
uvc_free_buffers().

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 34 insertions, 25 deletions

diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c
index ed6d5449741c..32c18229863b 100644
--- a/drivers/media/video/uvc/uvc_queue.c
+++ b/drivers/media/video/uvc/uvc_queue.c
@@ -90,6 +90,39 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
 }
 
 /*
+ * Free the video buffers.
+ *
+ * This function must be called with the queue lock held.
+ */
+static int __uvc_free_buffers(struct uvc_video_queue *queue)
+{
+        unsigned int i;
+
+        for (i = 0; i < queue->count; ++i) {
+                if (queue->buffer[i].vma_use_count != 0)
+                        return -EBUSY;
+        }
+
+        if (queue->count) {
+                vfree(queue->mem);
+                queue->count = 0;
+        }
+
+        return 0;
+}
+
+int uvc_free_buffers(struct uvc_video_queue *queue)
+{
+        int ret;
+
+        mutex_lock(&queue->mutex);
+        ret = __uvc_free_buffers(queue);
+        mutex_unlock(&queue->mutex);
+
+        return ret;
+}
+
+/*
  * Allocate the video buffers.
  *
  * Pages are reserved to make sure they will not be swapped, as they will be
@@ -110,7 +143,7 @@ int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
 
         mutex_lock(&queue->mutex);
 
-        if ((ret = uvc_free_buffers(queue)) < 0)
+        if ((ret = __uvc_free_buffers(queue)) < 0)
                 goto done;
 
         /* Bail out if no buffers should be allocated. */
@@ -152,28 +185,6 @@ done:
 }
 
 /*
- * Free the video buffers.
- *
- * This function must be called with the queue lock held.
- */
-int uvc_free_buffers(struct uvc_video_queue *queue)
-{
-        unsigned int i;
-
-        for (i = 0; i < queue->count; ++i) {
-                if (queue->buffer[i].vma_use_count != 0)
-                        return -EBUSY;
-        }
-
-        if (queue->count) {
-                vfree(queue->mem);
-                queue->count = 0;
-        }
-
-        return 0;
-}
-
-/*
  * Check if buffers have been allocated.
  */
 int uvc_queue_allocated(struct uvc_video_queue *queue)
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 0f865e97cf48..0fd9848bd9d7 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -494,11 +494,9 @@ static int uvc_v4l2_release(struct file *file)
         if (uvc_has_privileges(handle)) {
                 uvc_video_enable(stream, 0);
 
-                mutex_lock(&stream->queue.mutex);
                 if (uvc_free_buffers(&stream->queue) < 0)
                         uvc_printk(KERN_ERR, "uvc_v4l2_release: Unable to "
                                         "free buffers.\n");
-                mutex_unlock(&stream->queue.mutex);
         }
 
         /* Release the file handle. */