[PATCH 6/9] scsi_dh: add hp sw device handler

[Chandra Seetharaman <sekharan@us.ibm.com>]

Subject: scsi_dh: add hp sw device handler

From: Mike Christie <michaelc@cs.wisc.edu>

This patch adds a very basic scsi device handler for older hp boxes which
cannot be upgraded.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
---

 drivers/scsi/device_handler/Kconfig         |    6 	6 +	0 -	0 !
 drivers/scsi/device_handler/Makefile        |    1 	1 +	0 -	0 !
 drivers/scsi/device_handler/scsi_dh_hp_sw.c |  206 	206 +	0 -	0 !
 3 files changed, 213 insertions(+)

Index: linux-2.6.24-rc8/drivers/scsi/device_handler/Kconfig
===================================================================
--- linux-2.6.24-rc8.orig/drivers/scsi/device_handler/Kconfig
+++ linux-2.6.24-rc8/drivers/scsi/device_handler/Kconfig
@@ -18,5 +18,11 @@ config SCSI_DH_EMC
 	help
 	If you have a EMC CLARiiON select y. Otherwise, say N.
 
+config SCSI_DH_HP_SW
+	tristate "HP/COMPAQ MSA Device Handler"
+	help
+	If you have a HP/COMPAQ MSA device that requires START_STOP to
+	be sent to start it and cannot upgrade the firmware then select y.
+	Otherwise, say N.
 
 endif #SCSI_DH
Index: linux-2.6.24-rc8/drivers/scsi/device_handler/Makefile
===================================================================
--- linux-2.6.24-rc8.orig/drivers/scsi/device_handler/Makefile
+++ linux-2.6.24-rc8/drivers/scsi/device_handler/Makefile
@@ -3,3 +3,4 @@
 #
 
 obj-$(CONFIG_SCSI_DH_EMC)	+= scsi_dh_emc.o
+obj-$(CONFIG_SCSI_DH_HP_SW)	+= scsi_dh_hp_sw.o
Index: linux-2.6.24-rc8/drivers/scsi/device_handler/scsi_dh_hp_sw.c
===================================================================
--- /dev/null
+++ linux-2.6.24-rc8/drivers/scsi/device_handler/scsi_dh_hp_sw.c
@@ -0,0 +1,206 @@
+/*
+ * Basic HP/COMPAQ MSA 1000 support. This is only needed if your HW cannot be
+ * upgraded.
+ *
+ * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
+ * Copyright (C) 2006 Mike Christie
+ *
+ * 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; see the file COPYING.  If not, write to
+ * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/blkdev.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_driver.h>
+
+#define HP_SW_NAME	"hp_sw"
+
+#define HP_SW_TIMEOUT 30
+#define HP_SW_RETRIES 3
+
+struct hp_sw_dh_data {
+	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+	int retries;
+};
+
+static void hp_sw_done(struct request *req, int uptodate)
+{
+	struct request *act_req = req->end_io_data;
+	struct request_queue *q = req->q;
+	struct scsi_device *sdev = q->queuedata;
+	struct hp_sw_dh_data *hp_sw_dh_data = sdev->sdev_dh_data;
+	struct scsi_sense_hdr sshdr;
+	int rc = BLKERR_OK;
+
+	sdev_printk(KERN_INFO, sdev, "hp_sw_done %d\n", req->errors);
+
+	/*
+	 * This will at least get us going. Let Dave do the details.
+	 */
+	if (status_byte(req->errors) == CHECK_CONDITION &&
+	    scsi_normalize_sense(req->sense, req->sense_len, &sshdr)) {
+		/* tmp debug output */
+		__scsi_print_sense("hp_sw_done", req->sense, req->sense_len);
+
+		switch (sshdr.sense_key) {
+		case NOT_READY:
+			if ((sshdr.asc == 0x04) && (sshdr.ascq == 3)) {
+				rc = BLKERR_RETRY;
+				hp_sw_dh_data->retries++;
+				break;
+			}
+			/* fall through */
+		default:
+			hp_sw_dh_data->retries++;
+			rc = BLKERR_IMM_RETRY;
+		}
+	} else if (req->errors)
+		rc = BLKERR_IO;
+
+	if (rc == BLKERR_OK)
+		hp_sw_dh_data->retries = 0;
+	else if (hp_sw_dh_data->retries > HP_SW_RETRIES) {
+		hp_sw_dh_data->retries = 0;
+		rc = BLKERR_IO;
+	}
+
+	__blk_put_request(req->q, req);
+	scsi_blk_linux_cmd_done(act_req, rc);
+}
+
+static void hp_sw_transition(struct request *act_req)
+{
+	struct scsi_device *sdev = act_req->q->queuedata;
+	struct hp_sw_dh_data *hp_sw_dh_data = sdev->sdev_dh_data;
+	struct request *req;
+
+	sdev_printk(KERN_INFO, sdev, "hp_sw_done send START_STOP retries %d.\n",
+		   act_req->retries);
+
+	req = blk_get_request(sdev->request_queue, 0, GFP_ATOMIC);
+	if (!req) {
+		scsi_blk_linux_cmd_done(req, BLKERR_RES_TEMP_UNAVAIL);
+		return;
+	}
+
+	req->cmd_type = REQ_TYPE_BLOCK_PC;
+	req->cmd_flags |= REQ_FAILFAST;
+	req->cmd_len = COMMAND_SIZE(START_STOP);
+	memset(req->cmd, 0, MAX_COMMAND_SIZE);
+	req->cmd[0] = START_STOP;
+	req->cmd[4] = 1;	/* Start spin cycle */
+	req->timeout = HP_SW_TIMEOUT;
+	req->retries = HP_SW_RETRIES;
+	req->end_io_data = act_req;
+	req->sense = hp_sw_dh_data->sense;
+	memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+	req->sense_len = 0;
+
+	blk_execute_rq_nowait(req->q, NULL, req, 1, hp_sw_done);
+}
+
+static const struct {
+	char *vendor;
+	char *model;
+} hp_sw_dh_data_list[] = {
+	{"COMPAQ", "MSA1000"},
+	{"HP", "HSV100"},
+	{NULL, NULL},
+};
+
+static int hp_sw_bus_notify(struct notifier_block *, unsigned long, void *);
+
+static struct scsi_device_handler hp_sw_dh = {
+	.name		= HP_SW_NAME,
+	.module		= THIS_MODULE,
+	.nb.notifier_call = hp_sw_bus_notify,
+	.transition	= hp_sw_transition,
+};
+
+static int hp_sw_bus_notify(struct notifier_block *nb,
+			    unsigned long action, void *data)
+{
+	struct device *dev = data;
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct hp_sw_dh_data *dh_data;
+	int i, found = 0;
+	unsigned long flags;
+
+	if (action == BUS_NOTIFY_ADD_DEVICE) {
+		for (i = 0; hp_sw_dh_data_list[i].vendor; i++) {
+			if (!strncmp(sdev->vendor, hp_sw_dh_data_list[i].vendor,
+				     strlen(hp_sw_dh_data_list[i].vendor)) &&
+			    !strncmp(sdev->model, hp_sw_dh_data_list[i].model,
+				     strlen(hp_sw_dh_data_list[i].model))) {
+				found = 1;
+				break;
+			}
+		}
+		if (!found)
+			goto out;
+
+		dh_data = kzalloc(sizeof(*dh_data), GFP_KERNEL);
+		if (!dh_data) {
+			sdev_printk(KERN_ERR, sdev, "Attach Failed %s.\n",
+				    HP_SW_NAME);
+			goto out;
+		}
+
+		spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+		sdev->sdev_dh_data = dh_data;
+		sdev->sdev_dh = &hp_sw_dh;
+		spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+		sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n",
+			    HP_SW_NAME);
+	} else if (action == BUS_NOTIFY_DEL_DEVICE) {
+		if (sdev->sdev_dh != &hp_sw_dh)
+			goto out;
+
+		spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+		dh_data = sdev->sdev_dh_data;
+		sdev->sdev_dh_data = NULL;
+		sdev->sdev_dh = NULL;
+		spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+		sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n",
+			    HP_SW_NAME);
+
+		kfree(dh_data);
+	}
+
+out:
+	return 0;
+}
+
+static int __init hp_sw_init(void)
+{
+	return scsi_register_device_handler(&hp_sw_dh);
+}
+
+static void __exit hp_sw_exit(void)
+{
+	scsi_unregister_device_handler(&hp_sw_dh);
+}
+
+module_init(hp_sw_init);
+module_exit(hp_sw_exit);
+
+MODULE_DESCRIPTION("HP MSA 1000");
+MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu");
+MODULE_LICENSE("GPL");

-- 

----------------------------------------------------------------------
    Chandra Seetharaman               | Be careful what you choose....
              - sekharan@us.ibm.com   |      .......you may get it.
----------------------------------------------------------------------