get_dmabuf
if (!q->mem_ops->get_dmabuf) {
dbuf = call_ptr_memop(get_dmabuf,
.get_dmabuf = vb2_dc_get_dmabuf,
.get_dmabuf = vb2_dma_sg_get_dmabuf,
.get_dmabuf = vb2_vmalloc_get_dmabuf,
struct dma_buf *(*get_dmabuf)(struct vb2_buffer *vb,
if (!get_dmabuf(s, &dma, PAGE_ALIGN(32 * 1024)))