+/**
+ * lpfc_scsi_prep_dma_buf_s4 - DMA mapping for scsi buffer to SLI4 IF spec
+ * @phba: The Hba for which this call is being executed.
+ * @lpfc_cmd: The scsi buffer which is going to be mapped.
+ *
+ * This routine does the pci dma mapping for scatter-gather list of scsi cmnd
+ * field of @lpfc_cmd for device with SLI-4 interface spec.
+ *
+ * Return codes:
+ * 1 - Error
+ * 0 - Success
+ **/
+static int
+lpfc_scsi_prep_dma_buf_s4(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
+{
+ struct scsi_cmnd *scsi_cmnd = lpfc_cmd->pCmd;
+ struct scatterlist *sgel = NULL;
+ struct fcp_cmnd *fcp_cmnd = lpfc_cmd->fcp_cmnd;
+ struct sli4_sge *sgl = (struct sli4_sge *)lpfc_cmd->fcp_bpl;
+ IOCB_t *iocb_cmd = &lpfc_cmd->cur_iocbq.iocb;
+ dma_addr_t physaddr;
+ uint32_t num_bde = 0;
+ uint32_t dma_len;
+ uint32_t dma_offset = 0;
+ int nseg;
+
+ /*
+ * There are three possibilities here - use scatter-gather segment, use
+ * the single mapping, or neither. Start the lpfc command prep by
+ * bumping the bpl beyond the fcp_cmnd and fcp_rsp regions to the first
+ * data bde entry.
+ */
+ if (scsi_sg_count(scsi_cmnd)) {
+ /*
+ * The driver stores the segment count returned from pci_map_sg
+ * because this a count of dma-mappings used to map the use_sg
+ * pages. They are not guaranteed to be the same for those
+ * architectures that implement an IOMMU.
+ */
+
+ nseg = scsi_dma_map(scsi_cmnd);
+ if (unlikely(!nseg))
+ return 1;
+ sgl += 1;
+ /* clear the last flag in the fcp_rsp map entry */
+ sgl->word2 = le32_to_cpu(sgl->word2);
+ bf_set(lpfc_sli4_sge_last, sgl, 0);
+ sgl->word2 = cpu_to_le32(sgl->word2);
+ sgl += 1;
+
+ lpfc_cmd->seg_cnt = nseg;
+ if (lpfc_cmd->seg_cnt > phba->cfg_sg_seg_cnt) {
+ printk(KERN_ERR "%s: Too many sg segments from "
+ "dma_map_sg. Config %d, seg_cnt %d\n",
+ __func__, phba->cfg_sg_seg_cnt,
+ lpfc_cmd->seg_cnt);
+ scsi_dma_unmap(scsi_cmnd);
+ return 1;
+ }
+
+ /*
+ * The driver established a maximum scatter-gather segment count
+ * during probe that limits the number of sg elements in any
+ * single scsi command. Just run through the seg_cnt and format
+ * the sge's.
+ * When using SLI-3 the driver will try to fit all the BDEs into
+ * the IOCB. If it can't then the BDEs get added to a BPL as it
+ * does for SLI-2 mode.
+ */
+ scsi_for_each_sg(scsi_cmnd, sgel, nseg, num_bde) {
+ physaddr = sg_dma_address(sgel);
+ dma_len = sg_dma_len(sgel);
+ bf_set(lpfc_sli4_sge_len, sgl, sg_dma_len(sgel));
+ sgl->addr_lo = cpu_to_le32(putPaddrLow(physaddr));
+ sgl->addr_hi = cpu_to_le32(putPaddrHigh(physaddr));
+ if ((num_bde + 1) == nseg)
+ bf_set(lpfc_sli4_sge_last, sgl, 1);
+ else
+ bf_set(lpfc_sli4_sge_last, sgl, 0);
+ bf_set(lpfc_sli4_sge_offset, sgl, dma_offset);
+ sgl->word2 = cpu_to_le32(sgl->word2);
+ sgl->word3 = cpu_to_le32(sgl->word3);
+ dma_offset += dma_len;
+ sgl++;
+ }
+ } else {
+ sgl += 1;
+ /* clear the last flag in the fcp_rsp map entry */
+ sgl->word2 = le32_to_cpu(sgl->word2);
+ bf_set(lpfc_sli4_sge_last, sgl, 1);
+ sgl->word2 = cpu_to_le32(sgl->word2);
+ }
+
+ /*
+ * Finish initializing those IOCB fields that are dependent on the
+ * scsi_cmnd request_buffer. Note that for SLI-2 the bdeSize is
+ * explicitly reinitialized.
+ * all iocb memory resources are reused.
+ */
+ fcp_cmnd->fcpDl = cpu_to_be32(scsi_bufflen(scsi_cmnd));
+
+ /*
+ * Due to difference in data length between DIF/non-DIF paths,
+ * we need to set word 4 of IOCB here
+ */
+ iocb_cmd->un.fcpi.fcpi_parm = scsi_bufflen(scsi_cmnd);
+ return 0;
+}
+
+/**
+ * lpfc_scsi_prep_dma_buf - Wrapper function for DMA mapping of scsi buffer
+ * @phba: The Hba for which this call is being executed.
+ * @lpfc_cmd: The scsi buffer which is going to be mapped.
+ *
+ * This routine wraps the actual DMA mapping function pointer from the
+ * lpfc_hba struct.
+ *
+ * Return codes:
+ * 1 - Error
+ * 0 - Success
+ **/
+static inline int
+lpfc_scsi_prep_dma_buf(struct lpfc_hba *phba, struct lpfc_scsi_buf *lpfc_cmd)
+{
+ return phba->lpfc_scsi_prep_dma_buf(phba, lpfc_cmd);
+}
+