NVME_REG_VS
*(u32 *)(buf + NVME_REG_VS) = readl(bar + NVME_REG_VS);
ret = ctrl->ops->reg_read32(ctrl, NVME_REG_VS, &ctrl->vs);
dev->subsystem = readl(dev->bar + NVME_REG_VS) >= NVME_VS(1, 1, 0) ?
case NVME_REG_VS:
nvmet_pci_epf_bar_write32(ctrl, NVME_REG_VS, tctrl->subsys->ver);