Commit bf6477cc authored by Daniel Verkamp's avatar Daniel Verkamp
Browse files

nvme: remove dead code for zero-length SGL request 



_nvme_qpair_build_hw_sgl_request() will only be called for payload_size
!= 0, so every SGL will have at least one segment.  Drop the 'else' that
was handling nseg == 0, and add an assert to document the payload_size
requirement.

Change-Id: I48e2a862a7657ba85605c0d35c0b65dfac072167
Signed-off-by: default avatarDaniel Verkamp <daniel.verkamp@intel.com>
parent 69f97964

lib/nvme/nvme_qpair.c

+2 −4
Original line number Diff line number Diff line
@@ -665,6 +665,7 @@ _nvme_qpair_build_hw_sgl_request(struct spdk_nvme_qpair *qpair, struct nvme_requ 
	/*

	 * Build scattered payloads.

	 */

	nvme_assert(req->payload_size != 0, ("cannot build SGL for zero-length transfer\n"));

	nvme_assert(req->payload.type == NVME_PAYLOAD_TYPE_SGL, ("sgl payload type required\n"));

	nvme_assert(req->payload.u.sgl.reset_sgl_fn != NULL, ("sgl reset callback required\n"));

	nvme_assert(req->payload.u.sgl.next_sge_fn != NULL, ("sgl callback required\n"));
@@ -704,14 +705,11 @@ _nvme_qpair_build_hw_sgl_request(struct spdk_nvme_qpair *qpair, struct nvme_requ 
		req->cmd.dptr.sgl1.type = SPDK_NVME_SGL_TYPE_DATA_BLOCK;

		req->cmd.dptr.sgl1.address = phys_addr;

		req->cmd.dptr.sgl1.length = data_transfered;

	} else if (nseg > 1) {

	} else {

		/* For now we can only support 1 SGL segment in NVMe controller */

		req->cmd.dptr.sgl1.type = SPDK_NVME_SGL_TYPE_LAST_SEGMENT;

		req->cmd.dptr.sgl1.address = tr->prp_sgl_bus_addr;

		req->cmd.dptr.sgl1.length = nseg * sizeof(struct spdk_nvme_sgl_descriptor);

	} else {

		_nvme_fail_request_bad_vtophys(qpair, tr);

		return -1;

	}



	return 0;