int vb2_qbuf(struct vb2_queue *q, struct v4l2_buffer *b) { int ret; if (vb2_fileio_is_active(q)) { dprintk(1, "file io in progress\n"); return -EBUSY; } ret = vb2_queue_or_prepare_buf(q, b, "qbuf"); return ret ? ret : vb2_core_qbuf(q, b->index, b); } EXPORT_...