[SCSI] zfcp: Update FCP protocol related code

Use common data structures for FCP CMND, FCP RSP and related
definitions and remove zfcp private definitions. Split the FCP CMND
setup and FCP RSP evaluation code in seperate functions. Use inline
functions to not negatively impact the I/O path.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 112 insertions, 0 deletions

diff --git a/drivers/s390/scsi/zfcp_fc.h b/drivers/s390/scsi/zfcp_fc.h
new file mode 100644
index 00000000000..814fc2d2525
--- /dev/null
+++ b/drivers/s390/scsi/zfcp_fc.h
@@ -0,0 +1,112 @@
+/*
+ * zfcp device driver
+ *
+ * Fibre Channel related definitions and inline functions for the zfcp
+ * device driver
+ *
+ * Copyright IBM Corporation 2009
+ */
+
+#ifndef ZFCP_FC_H
+#define ZFCP_FC_H
+
+#include <scsi/fc/fc_fcp.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_tcq.h>
+
+/**
+ * zfcp_fc_scsi_to_fcp - setup FCP command with data from scsi_cmnd
+ * @fcp: fcp_cmnd to setup
+ * @scsi: scsi_cmnd where to get LUN, task attributes/flags and CDB
+ */
+static inline
+void zfcp_fc_scsi_to_fcp(struct fcp_cmnd *fcp, struct scsi_cmnd *scsi)
+{
+	char tag[2];
+
+	int_to_scsilun(scsi->device->lun, (struct scsi_lun *) &fcp->fc_lun);
+
+	if (scsi_populate_tag_msg(scsi, tag)) {
+		switch (tag[0]) {
+		case MSG_ORDERED_TAG:
+			fcp->fc_pri_ta |= FCP_PTA_ORDERED;
+			break;
+		case MSG_SIMPLE_TAG:
+			fcp->fc_pri_ta |= FCP_PTA_SIMPLE;
+			break;
+		};
+	} else
+		fcp->fc_pri_ta = FCP_PTA_SIMPLE;
+
+	if (scsi->sc_data_direction == DMA_FROM_DEVICE)
+		fcp->fc_flags |= FCP_CFL_RDDATA;
+	if (scsi->sc_data_direction == DMA_TO_DEVICE)
+		fcp->fc_flags |= FCP_CFL_WRDATA;
+
+	memcpy(fcp->fc_cdb, scsi->cmnd, scsi->cmd_len);
+
+	fcp->fc_dl = scsi_bufflen(scsi);
+}
+
+/**
+ * zfcp_fc_fcp_tm - setup FCP command as task management command
+ * @fcp: fcp_cmnd to setup
+ * @dev: scsi_device where to send the task management command
+ * @tm: task management flags to setup tm command
+ */
+static inline
+void zfcp_fc_fcp_tm(struct fcp_cmnd *fcp, struct scsi_device *dev, u8 tm_flags)
+{
+	int_to_scsilun(dev->lun, (struct scsi_lun *) &fcp->fc_lun);
+	fcp->fc_tm_flags |= tm_flags;
+}
+
+/**
+ * zfcp_fc_evap_fcp_rsp - evaluate FCP RSP IU and update scsi_cmnd accordingly
+ * @fcp_rsp: FCP RSP IU to evaluate
+ * @scsi: SCSI command where to update status and sense buffer
+ */
+static inline
+void zfcp_fc_eval_fcp_rsp(struct fcp_resp_with_ext *fcp_rsp,
+			  struct scsi_cmnd *scsi)
+{
+	struct fcp_resp_rsp_info *rsp_info;
+	char *sense;
+	u32 sense_len, resid;
+	u8 rsp_flags;
+
+	set_msg_byte(scsi, COMMAND_COMPLETE);
+	scsi->result |= fcp_rsp->resp.fr_status;
+
+	rsp_flags = fcp_rsp->resp.fr_flags;
+
+	if (unlikely(rsp_flags & FCP_RSP_LEN_VAL)) {
+		rsp_info = (struct fcp_resp_rsp_info *) &fcp_rsp[1];
+		if (rsp_info->rsp_code == FCP_TMF_CMPL)
+			set_host_byte(scsi, DID_OK);
+		else {
+			set_host_byte(scsi, DID_ERROR);
+			return;
+		}
+	}
+
+	if (unlikely(rsp_flags & FCP_SNS_LEN_VAL)) {
+		sense = (char *) &fcp_rsp[1];
+		if (rsp_flags & FCP_RSP_LEN_VAL)
+			sense += fcp_rsp->ext.fr_sns_len;
+		sense_len = min(fcp_rsp->ext.fr_sns_len,
+				(u32) SCSI_SENSE_BUFFERSIZE);
+		memcpy(scsi->sense_buffer, sense, sense_len);
+	}
+
+	if (unlikely(rsp_flags & FCP_RESID_UNDER)) {
+		resid = fcp_rsp->ext.fr_resid;
+		scsi_set_resid(scsi, resid);
+		if (scsi_bufflen(scsi) - resid < scsi->underflow &&
+		     !(rsp_flags & FCP_SNS_LEN_VAL) &&
+		     fcp_rsp->resp.fr_status == SAM_STAT_GOOD)
+			set_host_byte(scsi, DID_ERROR);
+	}
+}
+
+#endif