[SCSI] zfcp: enhancement of zfcp debug features

Debug features (DBFs) els_dbf, cmd_dbf and abt_dbf were removed and
san_dbf, hba_dbf and scsi_dbf were introduced. The erp_dbf did not
change.
The new traces improve debugging of problems with zfcp, scsi-stack,
multipath and hardware in the SAN. san_dbf traces things like ELS and
CT commands, hba_dbf saves HBA specific information of requests, and
scsi_dbf saves FCP and SCSI specific information of requests. Common
to all new DBFs is that they provide a so called structured view. This
significantly improves readability of the traces.

Signed-off-by: Andreas Herrmann <aherrman@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 988 insertions, 0 deletions

diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c
new file mode 100644
index 00000000000..fff1537335c
--- /dev/null
+++ b/drivers/s390/scsi/zfcp_dbf.c
@@ -0,0 +1,988 @@
+/*
+ *
+ * linux/drivers/s390/scsi/zfcp_dbf.c
+ *
+ * FCP adapter driver for IBM eServer zSeries
+ *
+ * Debugging facilities
+ *
+ * (C) Copyright IBM Corp. 2005
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#define ZFCP_DBF_REVISION "$Revision$"
+
+#include <asm/debug.h>
+#include <linux/ctype.h>
+#include "zfcp_ext.h"
+
+static u32 dbfsize = 4;
+
+module_param(dbfsize, uint, 0400);
+MODULE_PARM_DESC(dbfsize,
+		 "number of pages for each debug feature area (default 4)");
+
+#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_OTHER
+
+static inline int
+zfcp_dbf_stck(char *out_buf, const char *label, unsigned long long stck)
+{
+	unsigned long long sec;
+	struct timespec xtime;
+	int len = 0;
+
+	stck -= 0x8126d60e46000000LL - (0x3c26700LL * 1000000 * 4096);
+	sec = stck >> 12;
+	do_div(sec, 1000000);
+	xtime.tv_sec = sec;
+	stck -= (sec * 1000000) << 12;
+	xtime.tv_nsec = ((stck * 1000) >> 12);
+	len += sprintf(out_buf + len, "%-24s%011lu:%06lu\n",
+		       label, xtime.tv_sec, xtime.tv_nsec);
+
+	return len;
+}
+
+static int zfcp_dbf_tag(char *out_buf, const char *label, const char *tag)
+{
+	int len = 0, i;
+
+	len += sprintf(out_buf + len, "%-24s", label);
+	for (i = 0; i < ZFCP_DBF_TAG_SIZE; i++)
+		len += sprintf(out_buf + len, "%c", tag[i]);
+	len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+static int
+zfcp_dbf_view(char *out_buf, const char *label, const char *format, ...)
+{
+	va_list arg;
+	int len = 0;
+
+	len += sprintf(out_buf + len, "%-24s", label);
+	va_start(arg, format);
+	len += vsprintf(out_buf + len, format, arg);
+	va_end(arg);
+	len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+static int
+zfcp_dbf_view_dump(char *out_buf, const char *label,
+		   char *buffer, int buflen, int offset, int total_size)
+{
+	int len = 0;
+
+	if (offset == 0)
+		len += sprintf(out_buf + len, "%-24s  ", label);
+
+	while (buflen--) {
+		if (offset > 0) {
+			if ((offset % 32) == 0)
+				len += sprintf(out_buf + len, "\n%-24c  ", ' ');
+			else if ((offset % 4) == 0)
+				len += sprintf(out_buf + len, " ");
+		}
+		len += sprintf(out_buf + len, "%02x", *buffer++);
+		if (++offset == total_size) {
+			len += sprintf(out_buf + len, "\n");
+			break;
+		}
+	}
+
+	if (total_size == 0)
+		len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+static inline int
+zfcp_dbf_view_header(debug_info_t * id, struct debug_view *view, int area,
+		     debug_entry_t * entry, char *out_buf)
+{
+	struct zfcp_dbf_dump *dump = (struct zfcp_dbf_dump *)DEBUG_DATA(entry);
+	int len = 0;
+
+	if (strncmp(dump->tag, "dump", ZFCP_DBF_TAG_SIZE) != 0) {
+		len += zfcp_dbf_stck(out_buf + len, "timestamp",
+				     entry->id.stck);
+		len += zfcp_dbf_view(out_buf + len, "cpu", "%02i",
+				     entry->id.fields.cpuid);
+	} else {
+		len += zfcp_dbf_view_dump(out_buf + len, NULL,
+					  dump->data,
+					  dump->size,
+					  dump->offset, dump->total_size);
+		if ((dump->offset + dump->size) == dump->total_size)
+			len += sprintf(out_buf + len, "\n");
+	}
+
+	return len;
+}
+
+inline void zfcp_hba_dbf_event_fsf_response(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_adapter *adapter = fsf_req->adapter;
+	struct fsf_qtcb *qtcb = fsf_req->qtcb;
+	union fsf_prot_status_qual *prot_status_qual =
+	    &qtcb->prefix.prot_status_qual;
+	union fsf_status_qual *fsf_status_qual = &qtcb->header.fsf_status_qual;
+	struct scsi_cmnd *scsi_cmnd;
+	struct zfcp_port *port;
+	struct zfcp_unit *unit;
+	struct zfcp_send_els *send_els;
+	struct zfcp_hba_dbf_record *rec = &adapter->hba_dbf_buf;
+	struct zfcp_hba_dbf_record_response *response = &rec->type.response;
+	int level;
+	unsigned long flags;
+
+	spin_lock_irqsave(&adapter->hba_dbf_lock, flags);
+	memset(rec, 0, sizeof(struct zfcp_hba_dbf_record));
+	strncpy(rec->tag, "resp", ZFCP_DBF_TAG_SIZE);
+
+	if ((qtcb->prefix.prot_status != FSF_PROT_GOOD) &&
+	    (qtcb->prefix.prot_status != FSF_PROT_FSF_STATUS_PRESENTED)) {
+		strncpy(rec->tag2, "perr", ZFCP_DBF_TAG_SIZE);
+		level = 1;
+	} else if (qtcb->header.fsf_status != FSF_GOOD) {
+		strncpy(rec->tag2, "ferr", ZFCP_DBF_TAG_SIZE);
+		level = 1;
+	} else if ((fsf_req->fsf_command == FSF_QTCB_OPEN_PORT_WITH_DID) ||
+		   (fsf_req->fsf_command == FSF_QTCB_OPEN_LUN)) {
+		strncpy(rec->tag2, "open", ZFCP_DBF_TAG_SIZE);
+		level = 4;
+	} else if ((prot_status_qual->doubleword[0] != 0) ||
+		   (prot_status_qual->doubleword[1] != 0) ||
+		   (fsf_status_qual->doubleword[0] != 0) ||
+		   (fsf_status_qual->doubleword[1] != 0)) {
+		strncpy(rec->tag2, "qual", ZFCP_DBF_TAG_SIZE);
+		level = 3;
+	} else {
+		strncpy(rec->tag2, "norm", ZFCP_DBF_TAG_SIZE);
+		level = 6;
+	}
+
+	response->fsf_command = fsf_req->fsf_command;
+	response->fsf_reqid = (unsigned long)fsf_req;
+	response->fsf_seqno = fsf_req->seq_no;
+	response->fsf_issued = fsf_req->issued;
+	response->fsf_prot_status = qtcb->prefix.prot_status;
+	response->fsf_status = qtcb->header.fsf_status;
+	memcpy(response->fsf_prot_status_qual,
+	       prot_status_qual, FSF_PROT_STATUS_QUAL_SIZE);
+	memcpy(response->fsf_status_qual,
+	       fsf_status_qual, FSF_STATUS_QUALIFIER_SIZE);
+	response->fsf_req_status = fsf_req->status;
+	response->sbal_first = fsf_req->sbal_first;
+	response->sbal_curr = fsf_req->sbal_curr;
+	response->sbal_last = fsf_req->sbal_last;
+	response->pool = fsf_req->pool != NULL;
+	response->erp_action = (unsigned long)fsf_req->erp_action;
+
+	switch (fsf_req->fsf_command) {
+	case FSF_QTCB_FCP_CMND:
+		if (fsf_req->status & ZFCP_STATUS_FSFREQ_TASK_MANAGEMENT)
+			break;
+		scsi_cmnd = (struct scsi_cmnd *)fsf_req->data;
+		if (scsi_cmnd != NULL) {
+			response->data.send_fcp.scsi_cmnd
+			    = (unsigned long)scsi_cmnd;
+			response->data.send_fcp.scsi_serial
+			    = scsi_cmnd->serial_number;
+		}
+		break;
+
+	case FSF_QTCB_OPEN_PORT_WITH_DID:
+	case FSF_QTCB_CLOSE_PORT:
+	case FSF_QTCB_CLOSE_PHYSICAL_PORT:
+		port = (struct zfcp_port *)fsf_req->data;
+		response->data.port.wwpn = port->wwpn;
+		response->data.port.d_id = port->d_id;
+		response->data.port.port_handle = qtcb->header.port_handle;
+		break;
+
+	case FSF_QTCB_OPEN_LUN:
+	case FSF_QTCB_CLOSE_LUN:
+		unit = (struct zfcp_unit *)fsf_req->data;
+		port = unit->port;
+		response->data.unit.wwpn = port->wwpn;
+		response->data.unit.fcp_lun = unit->fcp_lun;
+		response->data.unit.port_handle = qtcb->header.port_handle;
+		response->data.unit.lun_handle = qtcb->header.lun_handle;
+		break;
+
+	case FSF_QTCB_SEND_ELS:
+		send_els = (struct zfcp_send_els *)fsf_req->data;
+		response->data.send_els.d_id = qtcb->bottom.support.d_id;
+		response->data.send_els.ls_code = send_els->ls_code >> 24;
+		break;
+
+	case FSF_QTCB_ABORT_FCP_CMND:
+	case FSF_QTCB_SEND_GENERIC:
+	case FSF_QTCB_EXCHANGE_CONFIG_DATA:
+	case FSF_QTCB_EXCHANGE_PORT_DATA:
+	case FSF_QTCB_DOWNLOAD_CONTROL_FILE:
+	case FSF_QTCB_UPLOAD_CONTROL_FILE:
+		break;
+	}
+
+	debug_event(adapter->hba_dbf, level,
+		    rec, sizeof(struct zfcp_hba_dbf_record));
+	spin_unlock_irqrestore(&adapter->hba_dbf_lock, flags);
+}
+
+inline void
+zfcp_hba_dbf_event_fsf_unsol(const char *tag, struct zfcp_adapter *adapter,
+			     struct fsf_status_read_buffer *status_buffer)
+{
+	struct zfcp_hba_dbf_record *rec = &adapter->hba_dbf_buf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&adapter->hba_dbf_lock, flags);
+	memset(rec, 0, sizeof(struct zfcp_hba_dbf_record));
+	strncpy(rec->tag, "stat", ZFCP_DBF_TAG_SIZE);
+	strncpy(rec->tag2, tag, ZFCP_DBF_TAG_SIZE);
+
+	rec->type.status.failed = adapter->status_read_failed;
+	if (status_buffer != NULL) {
+		rec->type.status.status_type = status_buffer->status_type;
+		rec->type.status.status_subtype = status_buffer->status_subtype;
+		memcpy(&rec->type.status.queue_designator,
+		       &status_buffer->queue_designator,
+		       sizeof(struct fsf_queue_designator));
+
+		switch (status_buffer->status_type) {
+		case FSF_STATUS_READ_SENSE_DATA_AVAIL:
+			rec->type.status.payload_size =
+			    ZFCP_DBF_UNSOL_PAYLOAD_SENSE_DATA_AVAIL;
+			break;
+
+		case FSF_STATUS_READ_BIT_ERROR_THRESHOLD:
+			rec->type.status.payload_size =
+			    ZFCP_DBF_UNSOL_PAYLOAD_BIT_ERROR_THRESHOLD;
+			break;
+
+		case FSF_STATUS_READ_LINK_DOWN:
+			rec->type.status.payload_size = sizeof(u64);
+			break;
+
+		}
+		memcpy(&rec->type.status.payload,
+		       &status_buffer->payload, rec->type.status.payload_size);
+	}
+
+	debug_event(adapter->hba_dbf, 2,
+		    rec, sizeof(struct zfcp_hba_dbf_record));
+	spin_unlock_irqrestore(&adapter->hba_dbf_lock, flags);
+}
+
+inline void
+zfcp_hba_dbf_event_qdio(struct zfcp_adapter *adapter, unsigned int status,
+			unsigned int qdio_error, unsigned int siga_error,
+			int sbal_index, int sbal_count)
+{
+	struct zfcp_hba_dbf_record *rec = &adapter->hba_dbf_buf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&adapter->hba_dbf_lock, flags);
+	memset(rec, 0, sizeof(struct zfcp_hba_dbf_record));
+	strncpy(rec->tag, "qdio", ZFCP_DBF_TAG_SIZE);
+	rec->type.qdio.status = status;
+	rec->type.qdio.qdio_error = qdio_error;
+	rec->type.qdio.siga_error = siga_error;
+	rec->type.qdio.sbal_index = sbal_index;
+	rec->type.qdio.sbal_count = sbal_count;
+	debug_event(adapter->hba_dbf, 0,
+		    rec, sizeof(struct zfcp_hba_dbf_record));
+	spin_unlock_irqrestore(&adapter->hba_dbf_lock, flags);
+}
+
+static inline int
+zfcp_hba_dbf_view_response(char *out_buf,
+			   struct zfcp_hba_dbf_record_response *rec)
+{
+	int len = 0;
+
+	len += zfcp_dbf_view(out_buf + len, "fsf_command", "0x%08x",
+			     rec->fsf_command);
+	len += zfcp_dbf_view(out_buf + len, "fsf_reqid", "0x%0Lx",
+			     rec->fsf_reqid);
+	len += zfcp_dbf_view(out_buf + len, "fsf_seqno", "0x%08x",
+			     rec->fsf_seqno);
+	len += zfcp_dbf_stck(out_buf + len, "fsf_issued", rec->fsf_issued);
+	len += zfcp_dbf_view(out_buf + len, "fsf_prot_status", "0x%08x",
+			     rec->fsf_prot_status);
+	len += zfcp_dbf_view(out_buf + len, "fsf_status", "0x%08x",
+			     rec->fsf_status);
+	len += zfcp_dbf_view_dump(out_buf + len, "fsf_prot_status_qual",
+				  rec->fsf_prot_status_qual,
+				  FSF_PROT_STATUS_QUAL_SIZE,
+				  0, FSF_PROT_STATUS_QUAL_SIZE);
+	len += zfcp_dbf_view_dump(out_buf + len, "fsf_status_qual",
+				  rec->fsf_status_qual,
+				  FSF_STATUS_QUALIFIER_SIZE,
+				  0, FSF_STATUS_QUALIFIER_SIZE);
+	len += zfcp_dbf_view(out_buf + len, "fsf_req_status", "0x%08x",
+			     rec->fsf_req_status);
+	len += zfcp_dbf_view(out_buf + len, "sbal_first", "0x%02x",
+			     rec->sbal_first);
+	len += zfcp_dbf_view(out_buf + len, "sbal_curr", "0x%02x",
+			     rec->sbal_curr);
+	len += zfcp_dbf_view(out_buf + len, "sbal_last", "0x%02x",
+			     rec->sbal_last);
+	len += zfcp_dbf_view(out_buf + len, "pool", "0x%02x", rec->pool);
+
+	switch (rec->fsf_command) {
+	case FSF_QTCB_FCP_CMND:
+		if (rec->fsf_req_status & ZFCP_STATUS_FSFREQ_TASK_MANAGEMENT)
+			break;
+		len += zfcp_dbf_view(out_buf + len, "scsi_cmnd", "0x%0Lx",
+				     rec->data.send_fcp.scsi_cmnd);
+		len += zfcp_dbf_view(out_buf + len, "scsi_serial", "0x%016Lx",
+				     rec->data.send_fcp.scsi_serial);
+		break;
+
+	case FSF_QTCB_OPEN_PORT_WITH_DID:
+	case FSF_QTCB_CLOSE_PORT:
+	case FSF_QTCB_CLOSE_PHYSICAL_PORT:
+		len += zfcp_dbf_view(out_buf + len, "wwpn", "0x%016Lx",
+				     rec->data.port.wwpn);
+		len += zfcp_dbf_view(out_buf + len, "d_id", "0x%06x",
+				     rec->data.port.d_id);
+		len += zfcp_dbf_view(out_buf + len, "port_handle", "0x%08x",
+				     rec->data.port.port_handle);
+		break;
+
+	case FSF_QTCB_OPEN_LUN:
+	case FSF_QTCB_CLOSE_LUN:
+		len += zfcp_dbf_view(out_buf + len, "wwpn", "0x%016Lx",
+				     rec->data.unit.wwpn);
+		len += zfcp_dbf_view(out_buf + len, "fcp_lun", "0x%016Lx",
+				     rec->data.unit.fcp_lun);
+		len += zfcp_dbf_view(out_buf + len, "port_handle", "0x%08x",
+				     rec->data.unit.port_handle);
+		len += zfcp_dbf_view(out_buf + len, "lun_handle", "0x%08x",
+				     rec->data.unit.lun_handle);
+		break;
+
+	case FSF_QTCB_SEND_ELS:
+		len += zfcp_dbf_view(out_buf + len, "d_id", "0x%06x",
+				     rec->data.send_els.d_id);
+		len += zfcp_dbf_view(out_buf + len, "ls_code", "0x%02x",
+				     rec->data.send_els.ls_code);
+		break;
+
+	case FSF_QTCB_ABORT_FCP_CMND:
+	case FSF_QTCB_SEND_GENERIC:
+	case FSF_QTCB_EXCHANGE_CONFIG_DATA:
+	case FSF_QTCB_EXCHANGE_PORT_DATA:
+	case FSF_QTCB_DOWNLOAD_CONTROL_FILE:
+	case FSF_QTCB_UPLOAD_CONTROL_FILE:
+		break;
+	}
+
+	return len;
+}
+
+static inline int
+zfcp_hba_dbf_view_status(char *out_buf, struct zfcp_hba_dbf_record_status *rec)
+{
+	int len = 0;
+
+	len += zfcp_dbf_view(out_buf + len, "failed", "0x%02x", rec->failed);
+	len += zfcp_dbf_view(out_buf + len, "status_type", "0x%08x",
+			     rec->status_type);
+	len += zfcp_dbf_view(out_buf + len, "status_subtype", "0x%08x",
+			     rec->status_subtype);
+	len += zfcp_dbf_view_dump(out_buf + len, "queue_designator",
+				  (char *)&rec->queue_designator,
+				  sizeof(struct fsf_queue_designator),
+				  0, sizeof(struct fsf_queue_designator));
+	len += zfcp_dbf_view_dump(out_buf + len, "payload",
+				  (char *)&rec->payload,
+				  rec->payload_size, 0, rec->payload_size);
+
+	return len;
+}
+
+static inline int
+zfcp_hba_dbf_view_qdio(char *out_buf, struct zfcp_hba_dbf_record_qdio *rec)
+{
+	int len = 0;
+
+	len += zfcp_dbf_view(out_buf + len, "status", "0x%08x", rec->status);
+	len += zfcp_dbf_view(out_buf + len, "qdio_error", "0x%08x",
+			     rec->qdio_error);
+	len += zfcp_dbf_view(out_buf + len, "siga_error", "0x%08x",
+			     rec->siga_error);
+	len += zfcp_dbf_view(out_buf + len, "sbal_index", "0x%02x",
+			     rec->sbal_index);
+	len += zfcp_dbf_view(out_buf + len, "sbal_count", "0x%02x",
+			     rec->sbal_count);
+
+	return len;
+}
+
+static int
+zfcp_hba_dbf_view_format(debug_info_t * id, struct debug_view *view,
+			 char *out_buf, const char *in_buf)
+{
+	struct zfcp_hba_dbf_record *rec = (struct zfcp_hba_dbf_record *)in_buf;
+	int len = 0;
+
+	if (strncmp(rec->tag, "dump", ZFCP_DBF_TAG_SIZE) == 0)
+		return 0;
+
+	len += zfcp_dbf_tag(out_buf + len, "tag", rec->tag);
+	if (isalpha(rec->tag2[0]))
+		len += zfcp_dbf_tag(out_buf + len, "tag2", rec->tag2);
+	if (strncmp(rec->tag, "resp", ZFCP_DBF_TAG_SIZE) == 0)
+		len += zfcp_hba_dbf_view_response(out_buf + len,
+						  &rec->type.response);
+	else if (strncmp(rec->tag, "stat", ZFCP_DBF_TAG_SIZE) == 0)
+		len += zfcp_hba_dbf_view_status(out_buf + len,
+						&rec->type.status);
+	else if (strncmp(rec->tag, "qdio", ZFCP_DBF_TAG_SIZE) == 0)
+		len += zfcp_hba_dbf_view_qdio(out_buf + len, &rec->type.qdio);
+
+	len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+struct debug_view zfcp_hba_dbf_view = {
+	"structured",
+	NULL,
+	&zfcp_dbf_view_header,
+	&zfcp_hba_dbf_view_format,
+	NULL,
+	NULL
+};
+
+inline void
+_zfcp_san_dbf_event_common_ct(const char *tag, struct zfcp_fsf_req *fsf_req,
+			      fc_id_t s_id, fc_id_t d_id,
+			      void *buffer, int buflen)
+{
+	struct zfcp_send_ct *send_ct = (struct zfcp_send_ct *)fsf_req->data;
+	struct zfcp_port *port = send_ct->port;
+	struct zfcp_adapter *adapter = port->adapter;
+	struct ct_hdr *header = (struct ct_hdr *)buffer;
+	struct zfcp_san_dbf_record *rec = &adapter->san_dbf_buf;
+	struct zfcp_san_dbf_record_ct *ct = &rec->type.ct;
+	unsigned long flags;
+
+	spin_lock_irqsave(&adapter->san_dbf_lock, flags);
+	memset(rec, 0, sizeof(struct zfcp_san_dbf_record));
+	strncpy(rec->tag, tag, ZFCP_DBF_TAG_SIZE);
+	rec->fsf_reqid = (unsigned long)fsf_req;
+	rec->fsf_seqno = fsf_req->seq_no;
+	rec->s_id = s_id;
+	rec->d_id = d_id;
+	if (strncmp(tag, "octc", ZFCP_DBF_TAG_SIZE) == 0) {
+		ct->type.request.cmd_req_code = header->cmd_rsp_code;
+		ct->type.request.revision = header->revision;
+		ct->type.request.gs_type = header->gs_type;
+		ct->type.request.gs_subtype = header->gs_subtype;
+		ct->type.request.options = header->options;
+		ct->type.request.max_res_size = header->max_res_size;
+	} else if (strncmp(tag, "rctc", ZFCP_DBF_TAG_SIZE) == 0) {
+		ct->type.response.cmd_rsp_code = header->cmd_rsp_code;
+		ct->type.response.revision = header->revision;
+		ct->type.response.reason_code = header->reason_code;
+		ct->type.response.reason_code_expl = header->reason_code_expl;
+		ct->type.response.vendor_unique = header->vendor_unique;
+	}
+	ct->payload_size =
+	    min(buflen - (int)sizeof(struct ct_hdr), ZFCP_DBF_CT_PAYLOAD);
+	memcpy(ct->payload, buffer + sizeof(struct ct_hdr), ct->payload_size);
+	debug_event(adapter->san_dbf, 3,
+		    rec, sizeof(struct zfcp_san_dbf_record));
+	spin_unlock_irqrestore(&adapter->san_dbf_lock, flags);
+}
+
+inline void zfcp_san_dbf_event_ct_request(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_send_ct *ct = (struct zfcp_send_ct *)fsf_req->data;
+	struct zfcp_port *port = ct->port;
+	struct zfcp_adapter *adapter = port->adapter;
+
+	_zfcp_san_dbf_event_common_ct("octc",
+				      fsf_req, adapter->s_id, port->d_id,
+				      zfcp_sg_to_address(ct->req),
+				      ct->req->length);
+}
+
+inline void zfcp_san_dbf_event_ct_response(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_send_ct *ct = (struct zfcp_send_ct *)fsf_req->data;
+	struct zfcp_port *port = ct->port;
+	struct zfcp_adapter *adapter = port->adapter;
+
+	_zfcp_san_dbf_event_common_ct("rctc",
+				      fsf_req, port->d_id, adapter->s_id,
+				      zfcp_sg_to_address(ct->resp),
+				      ct->resp->length);
+}
+
+static inline void
+_zfcp_san_dbf_event_common_els(const char *tag, int level,
+			       struct zfcp_fsf_req *fsf_req,
+			       fc_id_t s_id, fc_id_t d_id, u8 ls_code,
+			       void *buffer, int buflen)
+{
+	struct zfcp_adapter *adapter = fsf_req->adapter;
+	struct zfcp_san_dbf_record *rec = &adapter->san_dbf_buf;
+	struct zfcp_dbf_dump *dump = (struct zfcp_dbf_dump *)rec;
+	unsigned long flags;
+	int offset = 0;
+
+	spin_lock_irqsave(&adapter->san_dbf_lock, flags);
+	do {
+		memset(rec, 0, sizeof(struct zfcp_san_dbf_record));
+		if (offset == 0) {
+			strncpy(rec->tag, tag, ZFCP_DBF_TAG_SIZE);
+			rec->fsf_reqid = (unsigned long)fsf_req;
+			rec->fsf_seqno = fsf_req->seq_no;
+			rec->s_id = s_id;
+			rec->d_id = d_id;
+			rec->type.els.ls_code = ls_code;
+			buflen = min(buflen, ZFCP_DBF_ELS_MAX_PAYLOAD);
+			rec->type.els.payload_size = buflen;
+			memcpy(rec->type.els.payload,
+			       buffer, min(buflen, ZFCP_DBF_ELS_PAYLOAD));
+			offset += min(buflen, ZFCP_DBF_ELS_PAYLOAD);
+		} else {
+			strncpy(dump->tag, "dump", ZFCP_DBF_TAG_SIZE);
+			dump->total_size = buflen;
+			dump->offset = offset;
+			dump->size = min(buflen - offset,
+					 (int)sizeof(struct zfcp_san_dbf_record)
+					 - (int)sizeof(struct zfcp_dbf_dump));
+			memcpy(dump->data, buffer + offset, dump->size);
+			offset += dump->size;
+		}
+		debug_event(adapter->san_dbf, level,
+			    rec, sizeof(struct zfcp_san_dbf_record));
+	} while (offset < buflen);
+	spin_unlock_irqrestore(&adapter->san_dbf_lock, flags);
+}
+
+inline void zfcp_san_dbf_event_els_request(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_send_els *els = (struct zfcp_send_els *)fsf_req->data;
+
+	_zfcp_san_dbf_event_common_els("oels", 2,
+				       fsf_req, els->adapter->s_id, els->d_id,
+				       *(u8 *) zfcp_sg_to_address(els->req),
+				       zfcp_sg_to_address(els->req),
+				       els->req->length);
+}
+
+inline void zfcp_san_dbf_event_els_response(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_send_els *els = (struct zfcp_send_els *)fsf_req->data;
+
+	_zfcp_san_dbf_event_common_els("rels", 2,
+				       fsf_req, els->d_id, els->adapter->s_id,
+				       *(u8 *) zfcp_sg_to_address(els->req),
+				       zfcp_sg_to_address(els->resp),
+				       els->resp->length);
+}
+
+inline void zfcp_san_dbf_event_incoming_els(struct zfcp_fsf_req *fsf_req)
+{
+	struct zfcp_adapter *adapter = fsf_req->adapter;
+	struct fsf_status_read_buffer *status_buffer =
+	    (struct fsf_status_read_buffer *)fsf_req->data;
+	int length = (int)status_buffer->length -
+	    (int)((void *)&status_buffer->payload - (void *)status_buffer);
+
+	_zfcp_san_dbf_event_common_els("iels", 1,
+				       fsf_req, status_buffer->d_id,
+				       adapter->s_id,
+				       *(u8 *) status_buffer->payload,
+				       (void *)status_buffer->payload, length);
+}
+
+static int
+zfcp_san_dbf_view_format(debug_info_t * id, struct debug_view *view,
+			 char *out_buf, const char *in_buf)
+{
+	struct zfcp_san_dbf_record *rec = (struct zfcp_san_dbf_record *)in_buf;
+	char *buffer = NULL;
+	int buflen = 0, total = 0;
+	int len = 0;
+
+	if (strncmp(rec->tag, "dump", ZFCP_DBF_TAG_SIZE) == 0)
+		return 0;
+
+	len += zfcp_dbf_tag(out_buf + len, "tag", rec->tag);
+	len += zfcp_dbf_view(out_buf + len, "fsf_reqid", "0x%0Lx",
+			     rec->fsf_reqid);
+	len += zfcp_dbf_view(out_buf + len, "fsf_seqno", "0x%08x",
+			     rec->fsf_seqno);
+	len += zfcp_dbf_view(out_buf + len, "s_id", "0x%06x", rec->s_id);
+	len += zfcp_dbf_view(out_buf + len, "d_id", "0x%06x", rec->d_id);
+
+	if (strncmp(rec->tag, "octc", ZFCP_DBF_TAG_SIZE) == 0) {
+		len += zfcp_dbf_view(out_buf + len, "cmd_req_code", "0x%04x",
+				     rec->type.ct.type.request.cmd_req_code);
+		len += zfcp_dbf_view(out_buf + len, "revision", "0x%02x",
+				     rec->type.ct.type.request.revision);
+		len += zfcp_dbf_view(out_buf + len, "gs_type", "0x%02x",
+				     rec->type.ct.type.request.gs_type);
+		len += zfcp_dbf_view(out_buf + len, "gs_subtype", "0x%02x",
+				     rec->type.ct.type.request.gs_subtype);
+		len += zfcp_dbf_view(out_buf + len, "options", "0x%02x",
+				     rec->type.ct.type.request.options);
+		len += zfcp_dbf_view(out_buf + len, "max_res_size", "0x%04x",
+				     rec->type.ct.type.request.max_res_size);
+		total = rec->type.ct.payload_size;
+		buffer = rec->type.ct.payload;
+		buflen = min(total, ZFCP_DBF_CT_PAYLOAD);
+	} else if (strncmp(rec->tag, "rctc", ZFCP_DBF_TAG_SIZE) == 0) {
+		len += zfcp_dbf_view(out_buf + len, "cmd_rsp_code", "0x%04x",
+				     rec->type.ct.type.response.cmd_rsp_code);
+		len += zfcp_dbf_view(out_buf + len, "revision", "0x%02x",
+				     rec->type.ct.type.response.revision);
+		len += zfcp_dbf_view(out_buf + len, "reason_code", "0x%02x",
+				     rec->type.ct.type.response.reason_code);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "reason_code_expl", "0x%02x",
+				  rec->type.ct.type.response.reason_code_expl);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "vendor_unique", "0x%02x",
+				  rec->type.ct.type.response.vendor_unique);
+		total = rec->type.ct.payload_size;
+		buffer = rec->type.ct.payload;
+		buflen = min(total, ZFCP_DBF_CT_PAYLOAD);
+	} else if (strncmp(rec->tag, "oels", ZFCP_DBF_TAG_SIZE) == 0 ||
+		   strncmp(rec->tag, "rels", ZFCP_DBF_TAG_SIZE) == 0 ||
+		   strncmp(rec->tag, "iels", ZFCP_DBF_TAG_SIZE) == 0) {
+		len += zfcp_dbf_view(out_buf + len, "ls_code", "0x%02x",
+				     rec->type.els.ls_code);
+		total = rec->type.els.payload_size;
+		buffer = rec->type.els.payload;
+		buflen = min(total, ZFCP_DBF_ELS_PAYLOAD);
+	}
+
+	len += zfcp_dbf_view_dump(out_buf + len, "payload",
+				  buffer, buflen, 0, total);
+
+	if (buflen == total)
+		len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+struct debug_view zfcp_san_dbf_view = {
+	"structured",
+	NULL,
+	&zfcp_dbf_view_header,
+	&zfcp_san_dbf_view_format,
+	NULL,
+	NULL
+};
+
+static inline void
+_zfcp_scsi_dbf_event_common(const char *tag, const char *tag2, int level,
+			    struct zfcp_adapter *adapter,
+			    struct scsi_cmnd *scsi_cmnd,
+			    struct zfcp_fsf_req *new_fsf_req)
+{
+	struct zfcp_fsf_req *fsf_req =
+	    (struct zfcp_fsf_req *)scsi_cmnd->host_scribble;
+	struct zfcp_scsi_dbf_record *rec = &adapter->scsi_dbf_buf;
+	struct zfcp_dbf_dump *dump = (struct zfcp_dbf_dump *)rec;
+	unsigned long flags;
+	struct fcp_rsp_iu *fcp_rsp;
+	char *fcp_rsp_info = NULL, *fcp_sns_info = NULL;
+	int offset = 0, buflen = 0;
+
+	spin_lock_irqsave(&adapter->scsi_dbf_lock, flags);
+	do {
+		memset(rec, 0, sizeof(struct zfcp_scsi_dbf_record));
+		if (offset == 0) {
+			strncpy(rec->tag, tag, ZFCP_DBF_TAG_SIZE);
+			strncpy(rec->tag2, tag2, ZFCP_DBF_TAG_SIZE);
+			if (scsi_cmnd->device) {
+				rec->scsi_id = scsi_cmnd->device->id;
+				rec->scsi_lun = scsi_cmnd->device->lun;
+			}
+			rec->scsi_result = scsi_cmnd->result;
+			rec->scsi_cmnd = (unsigned long)scsi_cmnd;
+			rec->scsi_serial = scsi_cmnd->serial_number;
+			memcpy(rec->scsi_opcode,
+			       &scsi_cmnd->cmnd,
+			       min((int)scsi_cmnd->cmd_len,
+				   ZFCP_DBF_SCSI_OPCODE));
+			rec->scsi_retries = scsi_cmnd->retries;
+			rec->scsi_allowed = scsi_cmnd->allowed;
+			if (fsf_req != NULL) {
+				fcp_rsp = (struct fcp_rsp_iu *)
+				    &(fsf_req->qtcb->bottom.io.fcp_rsp);
+				fcp_rsp_info =
+				    zfcp_get_fcp_rsp_info_ptr(fcp_rsp);
+				fcp_sns_info =
+				    zfcp_get_fcp_sns_info_ptr(fcp_rsp);
+
+				rec->type.fcp.rsp_validity =
+				    fcp_rsp->validity.value;
+				rec->type.fcp.rsp_scsi_status =
+				    fcp_rsp->scsi_status;
+				rec->type.fcp.rsp_resid = fcp_rsp->fcp_resid;
+				if (fcp_rsp->validity.bits.fcp_rsp_len_valid)
+					rec->type.fcp.rsp_code =
+					    *(fcp_rsp_info + 3);
+				if (fcp_rsp->validity.bits.fcp_sns_len_valid) {
+					buflen = min((int)fcp_rsp->fcp_sns_len,
+						     ZFCP_DBF_SCSI_MAX_FCP_SNS_INFO);
+					rec->type.fcp.sns_info_len = buflen;
+					memcpy(rec->type.fcp.sns_info,
+					       fcp_sns_info,
+					       min(buflen,
+						   ZFCP_DBF_SCSI_FCP_SNS_INFO));
+					offset += min(buflen,
+						      ZFCP_DBF_SCSI_FCP_SNS_INFO);
+				}
+
+				rec->fsf_reqid = (unsigned long)fsf_req;
+				rec->fsf_seqno = fsf_req->seq_no;
+				rec->fsf_issued = fsf_req->issued;
+			}
+			if (new_fsf_req != NULL) {
+				rec->type.new_fsf_req.fsf_reqid =
+				    (unsigned long)
+				    new_fsf_req;
+				rec->type.new_fsf_req.fsf_seqno =
+				    new_fsf_req->seq_no;
+				rec->type.new_fsf_req.fsf_issued =
+				    new_fsf_req->issued;
+			}
+		} else {
+			strncpy(dump->tag, "dump", ZFCP_DBF_TAG_SIZE);
+			dump->total_size = buflen;
+			dump->offset = offset;
+			dump->size = min(buflen - offset,
+					 (int)sizeof(struct
+						     zfcp_scsi_dbf_record) -
+					 (int)sizeof(struct zfcp_dbf_dump));
+			memcpy(dump->data, fcp_sns_info + offset, dump->size);
+			offset += dump->size;
+		}
+		debug_event(adapter->scsi_dbf, level,
+			    rec, sizeof(struct zfcp_scsi_dbf_record));
+	} while (offset < buflen);
+	spin_unlock_irqrestore(&adapter->scsi_dbf_lock, flags);
+}
+
+inline void
+zfcp_scsi_dbf_event_result(const char *tag, int level,
+			   struct zfcp_adapter *adapter,
+			   struct scsi_cmnd *scsi_cmnd)
+{
+	_zfcp_scsi_dbf_event_common("rslt",
+				    tag, level, adapter, scsi_cmnd, NULL);
+}
+
+inline void
+zfcp_scsi_dbf_event_abort(const char *tag, struct zfcp_adapter *adapter,
+			  struct scsi_cmnd *scsi_cmnd,
+			  struct zfcp_fsf_req *new_fsf_req)
+{
+	_zfcp_scsi_dbf_event_common("abrt",
+				    tag, 1, adapter, scsi_cmnd, new_fsf_req);
+}
+
+inline void
+zfcp_scsi_dbf_event_devreset(const char *tag, u8 flag, struct zfcp_unit *unit,
+			     struct scsi_cmnd *scsi_cmnd)
+{
+	struct zfcp_adapter *adapter = unit->port->adapter;
+
+	_zfcp_scsi_dbf_event_common(flag == FCP_TARGET_RESET ? "trst" : "lrst",
+				    tag, 1, adapter, scsi_cmnd, NULL);
+}
+
+static int
+zfcp_scsi_dbf_view_format(debug_info_t * id, struct debug_view *view,
+			  char *out_buf, const char *in_buf)
+{
+	struct zfcp_scsi_dbf_record *rec =
+	    (struct zfcp_scsi_dbf_record *)in_buf;
+	int len = 0;
+
+	if (strncmp(rec->tag, "dump", ZFCP_DBF_TAG_SIZE) == 0)
+		return 0;
+
+	len += zfcp_dbf_tag(out_buf + len, "tag", rec->tag);
+	len += zfcp_dbf_tag(out_buf + len, "tag2", rec->tag2);
+	len += zfcp_dbf_view(out_buf + len, "scsi_id", "0x%08x", rec->scsi_id);
+	len += zfcp_dbf_view(out_buf + len, "scsi_lun", "0x%08x",
+			     rec->scsi_lun);
+	len += zfcp_dbf_view(out_buf + len, "scsi_result", "0x%08x",
+			     rec->scsi_result);
+	len += zfcp_dbf_view(out_buf + len, "scsi_cmnd", "0x%0Lx",
+			     rec->scsi_cmnd);
+	len += zfcp_dbf_view(out_buf + len, "scsi_serial", "0x%016Lx",
+			     rec->scsi_serial);
+	len += zfcp_dbf_view_dump(out_buf + len, "scsi_opcode",
+				  rec->scsi_opcode,
+				  ZFCP_DBF_SCSI_OPCODE,
+				  0, ZFCP_DBF_SCSI_OPCODE);
+	len += zfcp_dbf_view(out_buf + len, "scsi_retries", "0x%02x",
+			     rec->scsi_retries);
+	len += zfcp_dbf_view(out_buf + len, "scsi_allowed", "0x%02x",
+			     rec->scsi_allowed);
+	len += zfcp_dbf_view(out_buf + len, "fsf_reqid", "0x%0Lx",
+			     rec->fsf_reqid);
+	len += zfcp_dbf_view(out_buf + len, "fsf_seqno", "0x%08x",
+			     rec->fsf_seqno);
+	len += zfcp_dbf_stck(out_buf + len, "fsf_issued", rec->fsf_issued);
+	if (strncmp(rec->tag, "rslt", ZFCP_DBF_TAG_SIZE) == 0) {
+		len +=
+		    zfcp_dbf_view(out_buf + len, "fcp_rsp_validity", "0x%02x",
+				  rec->type.fcp.rsp_validity);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "fcp_rsp_scsi_status",
+				  "0x%02x", rec->type.fcp.rsp_scsi_status);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "fcp_rsp_resid", "0x%08x",
+				  rec->type.fcp.rsp_resid);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "fcp_rsp_code", "0x%08x",
+				  rec->type.fcp.rsp_code);
+		len +=
+		    zfcp_dbf_view(out_buf + len, "fcp_sns_info_len", "0x%08x",
+				  rec->type.fcp.sns_info_len);
+		len +=
+		    zfcp_dbf_view_dump(out_buf + len, "fcp_sns_info",
+				       rec->type.fcp.sns_info,
+				       min((int)rec->type.fcp.sns_info_len,
+					   ZFCP_DBF_SCSI_FCP_SNS_INFO), 0,
+				       rec->type.fcp.sns_info_len);
+	} else if (strncmp(rec->tag, "abrt", ZFCP_DBF_TAG_SIZE) == 0) {
+		len += zfcp_dbf_view(out_buf + len, "fsf_reqid_abort", "0x%0Lx",
+				     rec->type.new_fsf_req.fsf_reqid);
+		len += zfcp_dbf_view(out_buf + len, "fsf_seqno_abort", "0x%08x",
+				     rec->type.new_fsf_req.fsf_seqno);
+		len += zfcp_dbf_stck(out_buf + len, "fsf_issued",
+				     rec->type.new_fsf_req.fsf_issued);
+	} else if ((strncmp(rec->tag, "trst", ZFCP_DBF_TAG_SIZE) == 0) ||
+		   (strncmp(rec->tag, "lrst", ZFCP_DBF_TAG_SIZE) == 0)) {
+		len += zfcp_dbf_view(out_buf + len, "fsf_reqid_reset", "0x%0Lx",
+				     rec->type.new_fsf_req.fsf_reqid);
+		len += zfcp_dbf_view(out_buf + len, "fsf_seqno_reset", "0x%08x",
+				     rec->type.new_fsf_req.fsf_seqno);
+		len += zfcp_dbf_stck(out_buf + len, "fsf_issued",
+				     rec->type.new_fsf_req.fsf_issued);
+	}
+
+	len += sprintf(out_buf + len, "\n");
+
+	return len;
+}
+
+struct debug_view zfcp_scsi_dbf_view = {
+	"structured",
+	NULL,
+	&zfcp_dbf_view_header,
+	&zfcp_scsi_dbf_view_format,
+	NULL,
+	NULL
+};
+
+/**
+ * zfcp_adapter_debug_register - registers debug feature for an adapter
+ * @adapter: pointer to adapter for which debug features should be registered
+ * return: -ENOMEM on error, 0 otherwise
+ */
+int zfcp_adapter_debug_register(struct zfcp_adapter *adapter)
+{
+	char dbf_name[DEBUG_MAX_NAME_LEN];
+
+	/* debug feature area which records recovery activity */
+	spin_lock_init(&adapter->erp_dbf_lock);
+	sprintf(dbf_name, "zfcp_%s_erp", zfcp_get_busid_by_adapter(adapter));
+	adapter->erp_dbf = debug_register(dbf_name, dbfsize, 2,
+					  sizeof(struct zfcp_erp_dbf_record));
+	if (!adapter->erp_dbf)
+		goto failed;
+	debug_register_view(adapter->erp_dbf, &debug_hex_ascii_view);
+	debug_set_level(adapter->erp_dbf, 3);
+
+	/* debug feature area which records HBA (FSF and QDIO) conditions */
+	spin_lock_init(&adapter->hba_dbf_lock);
+	sprintf(dbf_name, "zfcp_%s_hba", zfcp_get_busid_by_adapter(adapter));
+	adapter->hba_dbf = debug_register(dbf_name, dbfsize, 1,
+					  sizeof(struct zfcp_hba_dbf_record));
+	if (!adapter->hba_dbf)
+		goto failed;
+	debug_register_view(adapter->hba_dbf, &debug_hex_ascii_view);
+	debug_register_view(adapter->hba_dbf, &zfcp_hba_dbf_view);
+	debug_set_level(adapter->hba_dbf, 3);
+
+	/* debug feature area which records SAN command failures and recovery */
+	spin_lock_init(&adapter->san_dbf_lock);
+	sprintf(dbf_name, "zfcp_%s_san", zfcp_get_busid_by_adapter(adapter));
+	adapter->san_dbf = debug_register(dbf_name, dbfsize, 1,
+					  sizeof(struct zfcp_san_dbf_record));
+	if (!adapter->san_dbf)
+		goto failed;
+	debug_register_view(adapter->san_dbf, &debug_hex_ascii_view);
+	debug_register_view(adapter->san_dbf, &zfcp_san_dbf_view);
+	debug_set_level(adapter->san_dbf, 6);
+
+	/* debug feature area which records SCSI command failures and recovery */
+	spin_lock_init(&adapter->scsi_dbf_lock);
+	sprintf(dbf_name, "zfcp_%s_scsi", zfcp_get_busid_by_adapter(adapter));
+	adapter->scsi_dbf = debug_register(dbf_name, dbfsize, 1,
+					   sizeof(struct zfcp_scsi_dbf_record));
+	if (!adapter->scsi_dbf)
+		goto failed;
+	debug_register_view(adapter->scsi_dbf, &debug_hex_ascii_view);
+	debug_register_view(adapter->scsi_dbf, &zfcp_scsi_dbf_view);
+	debug_set_level(adapter->scsi_dbf, 3);
+
+	return 0;
+
+ failed:
+	zfcp_adapter_debug_unregister(adapter);
+
+	return -ENOMEM;
+}
+
+/**
+ * zfcp_adapter_debug_unregister - unregisters debug feature for an adapter
+ * @adapter: pointer to adapter for which debug features should be unregistered
+ */
+void zfcp_adapter_debug_unregister(struct zfcp_adapter *adapter)
+{
+	debug_unregister(adapter->scsi_dbf);
+	debug_unregister(adapter->san_dbf);
+	debug_unregister(adapter->hba_dbf);
+	debug_unregister(adapter->erp_dbf);
+	adapter->scsi_dbf = NULL;
+	adapter->san_dbf = NULL;
+	adapter->hba_dbf = NULL;
+	adapter->erp_dbf = NULL;
+}
+
+#undef ZFCP_LOG_AREA