gpu: ion: fix page offset in dma_buf_kmap()

Signed-off-by: Greg Hackmann <ghackmann@google.com>
[jstultz: modified patch to apply to staging directory]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ion/ion.c

@@ -846,7 +846,7 @@ static void ion_dma_buf_release(struct dma_buf *dmabuf)
 static void *ion_dma_buf_kmap(struct dma_buf *dmabuf, unsigned long offset)
 {
 	struct ion_buffer *buffer = dmabuf->priv;
-	return buffer->vaddr + offset;
+	return buffer->vaddr + offset * PAGE_SIZE;
 }
 
 static void ion_dma_buf_kunmap(struct dma_buf *dmabuf, unsigned long offset,