static inline blk_status_t nvme_setup_rw()

in host/core.c [915:976]

• 49 lines of code
• 13 McCabe index (conditional complexity)

static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
		struct request *req, struct nvme_command *cmnd,
		enum nvme_opcode op)
{
	struct nvme_ctrl *ctrl = ns->ctrl;
	u16 control = 0;
	u32 dsmgmt = 0;

	if (req->cmd_flags & REQ_FUA)
		control |= NVME_RW_FUA;
	if (req->cmd_flags & (REQ_FAILFAST_DEV | REQ_RAHEAD))
		control |= NVME_RW_LR;

	if (req->cmd_flags & REQ_RAHEAD)
		dsmgmt |= NVME_RW_DSM_FREQ_PREFETCH;

	cmnd->rw.opcode = op;
	cmnd->rw.flags = 0;
	cmnd->rw.nsid = cpu_to_le32(ns->head->ns_id);
	cmnd->rw.rsvd2 = 0;
	cmnd->rw.metadata = 0;
	cmnd->rw.slba = cpu_to_le64(nvme_sect_to_lba(ns, blk_rq_pos(req)));
	cmnd->rw.length = cpu_to_le16((blk_rq_bytes(req) >> ns->lba_shift) - 1);
	cmnd->rw.reftag = 0;
	cmnd->rw.apptag = 0;
	cmnd->rw.appmask = 0;

	if (req_op(req) == REQ_OP_WRITE && ctrl->nr_streams)
		nvme_assign_write_stream(ctrl, req, &control, &dsmgmt);

	if (ns->ms) {
		/*
		 * If formated with metadata, the block layer always provides a
		 * metadata buffer if CONFIG_BLK_DEV_INTEGRITY is enabled.  Else
		 * we enable the PRACT bit for protection information or set the
		 * namespace capacity to zero to prevent any I/O.
		 */
		if (!blk_integrity_rq(req)) {
			if (WARN_ON_ONCE(!nvme_ns_has_pi(ns)))
				return BLK_STS_NOTSUPP;
			control |= NVME_RW_PRINFO_PRACT;
		}

		switch (ns->pi_type) {
		case NVME_NS_DPS_PI_TYPE3:
			control |= NVME_RW_PRINFO_PRCHK_GUARD;
			break;
		case NVME_NS_DPS_PI_TYPE1:
		case NVME_NS_DPS_PI_TYPE2:
			control |= NVME_RW_PRINFO_PRCHK_GUARD |
					NVME_RW_PRINFO_PRCHK_REF;
			if (op == nvme_cmd_zone_append)
				control |= NVME_RW_APPEND_PIREMAP;
			cmnd->rw.reftag = cpu_to_le32(t10_pi_ref_tag(req));
			break;
		}
	}

	cmnd->rw.control = cpu_to_le16(control);
	cmnd->rw.dsmgmt = cpu_to_le32(dsmgmt);
	return 0;
}