NVME_MAX_SGL_DESCRIPTORS
struct nvme_sgl_descriptor sgl[NVME_MAX_SGL_DESCRIPTORS];
if (nseg >= NVME_MAX_SGL_DESCRIPTORS) {
restrictions.max_segment_count = (NVME_MAX_SGL_DESCRIPTORS / 2);
NVME_MAX_SGL_DESCRIPTORS / 2);