[SCSI] hpsa: add driver for HP Smart Array controllers.

This driver supports a subset of HP Smart Array Controllers.
It is a SCSI alternative to the cciss driver.

[akpm@linux-foundation.org: avoid helpful cleanup patches]
[achiang@hp.com: make device attrs static]
[akpm@linux-foundation.org: msleep() does set_current_state() itself]
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: Mike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

5 files changed, 4141 insertions, 0 deletions

diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 36900c71a592..9191d1ea6451 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -388,6 +388,16 @@ config BLK_DEV_3W_XXXX_RAID
 	  Please read the comments at the top of
 	  <file:drivers/scsi/3w-xxxx.c>.
 
+config SCSI_HPSA
+	tristate "HP Smart Array SCSI driver"
+	depends on PCI && SCSI
+	help
+	  This driver supports HP Smart Array Controllers (circa 2009).
+	  It is a SCSI alternative to the cciss driver, which is a block
+	  driver.  Anyone wishing to use HP Smart Array controllers who
+	  would prefer the devices be presented to linux as SCSI devices,
+	  rather than as generic block devices should say Y here.
+
 config SCSI_3W_9XXX
 	tristate "3ware 9xxx SATA-RAID support"
 	depends on PCI && SCSI
diff --git a/drivers/scsi/Makefile b/drivers/scsi/Makefile
index 280d3c657d60..92a8c500b23d 100644
--- a/drivers/scsi/Makefile
+++ b/drivers/scsi/Makefile
@@ -91,6 +91,7 @@ obj-$(CONFIG_SCSI_BFA_FC)	+= bfa/
 obj-$(CONFIG_SCSI_PAS16)	+= pas16.o
 obj-$(CONFIG_SCSI_T128)		+= t128.o
 obj-$(CONFIG_SCSI_DMX3191D)	+= dmx3191d.o
+obj-$(CONFIG_SCSI_HPSA)		+= hpsa.o
 obj-$(CONFIG_SCSI_DTC3280)	+= dtc.o
 obj-$(CONFIG_SCSI_SYM53C8XX_2)	+= sym53c8xx_2/
 obj-$(CONFIG_SCSI_ZALON)	+= zalon7xx.o
diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
new file mode 100644
index 000000000000..bb96fdd58e23
--- /dev/null
+++ b/drivers/scsi/hpsa.c
@@ -0,0 +1,3531 @@
+/*
+ *    Disk Array driver for HP Smart Array SAS controllers
+ *    Copyright 2000, 2009 Hewlett-Packard Development Company, L.P.
+ *
+ *    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; version 2 of the License.
+ *
+ *    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, GOOD TITLE or
+ *    NON INFRINGEMENT.  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.
+ *
+ *    Questions/Comments/Bugfixes to iss_storagedev@hp.com
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/timer.h>
+#include <linux/seq_file.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/smp_lock.h>
+#include <linux/compat.h>
+#include <linux/blktrace_api.h>
+#include <linux/uaccess.h>
+#include <linux/io.h>
+#include <linux/dma-mapping.h>
+#include <linux/completion.h>
+#include <linux/moduleparam.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+#include <linux/cciss_ioctl.h>
+#include <linux/string.h>
+#include <linux/bitmap.h>
+#include <asm/atomic.h>
+#include <linux/kthread.h>
+#include "hpsa_cmd.h"
+#include "hpsa.h"
+
+/* HPSA_DRIVER_VERSION must be 3 byte values (0-255) separated by '.' */
+#define HPSA_DRIVER_VERSION "1.0.0"
+#define DRIVER_NAME "HP HPSA Driver (v " HPSA_DRIVER_VERSION ")"
+
+/* How long to wait (in milliseconds) for board to go into simple mode */
+#define MAX_CONFIG_WAIT 30000
+#define MAX_IOCTL_CONFIG_WAIT 1000
+
+/*define how many times we will try a command because of bus resets */
+#define MAX_CMD_RETRIES 3
+
+/* Embedded module documentation macros - see modules.h */
+MODULE_AUTHOR("Hewlett-Packard Company");
+MODULE_DESCRIPTION("Driver for HP Smart Array Controller version " \
+	HPSA_DRIVER_VERSION);
+MODULE_SUPPORTED_DEVICE("HP Smart Array Controllers");
+MODULE_VERSION(HPSA_DRIVER_VERSION);
+MODULE_LICENSE("GPL");
+
+static int hpsa_allow_any;
+module_param(hpsa_allow_any, int, S_IRUGO|S_IWUSR);
+MODULE_PARM_DESC(hpsa_allow_any,
+		"Allow hpsa driver to access unknown HP Smart Array hardware");
+
+/* define the PCI info for the cards we can control */
+static const struct pci_device_id hpsa_pci_device_id[] = {
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSC,     0x103C, 0x3223},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSC,     0x103C, 0x3234},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSC,     0x103C, 0x323D},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x3241},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x3243},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x3245},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x3247},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x3249},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x324a},
+	{PCI_VENDOR_ID_HP,     PCI_DEVICE_ID_HP_CISSE,     0x103C, 0x324b},
+	{PCI_VENDOR_ID_HP,     PCI_ANY_ID,             PCI_ANY_ID, PCI_ANY_ID,
+		PCI_CLASS_STORAGE_RAID << 8, 0xffff << 8, 0},
+	{0,}
+};
+
+MODULE_DEVICE_TABLE(pci, hpsa_pci_device_id);
+
+/*  board_id = Subsystem Device ID & Vendor ID
+ *  product = Marketing Name for the board
+ *  access = Address of the struct of function pointers
+ */
+static struct board_type products[] = {
+	{0x3223103C, "Smart Array P800", &SA5_access},
+	{0x3234103C, "Smart Array P400", &SA5_access},
+	{0x323d103c, "Smart Array P700M", &SA5_access},
+	{0x3241103C, "Smart Array P212", &SA5_access},
+	{0x3243103C, "Smart Array P410", &SA5_access},
+	{0x3245103C, "Smart Array P410i", &SA5_access},
+	{0x3247103C, "Smart Array P411", &SA5_access},
+	{0x3249103C, "Smart Array P812", &SA5_access},
+	{0x324a103C, "Smart Array P712m", &SA5_access},
+	{0x324b103C, "Smart Array P711m", &SA5_access},
+	{0xFFFF103C, "Unknown Smart Array", &SA5_access},
+};
+
+static int number_of_controllers;
+
+static irqreturn_t do_hpsa_intr(int irq, void *dev_id);
+static int hpsa_ioctl(struct scsi_device *dev, int cmd, void *arg);
+static void start_io(struct ctlr_info *h);
+
+#ifdef CONFIG_COMPAT
+static int hpsa_compat_ioctl(struct scsi_device *dev, int cmd, void *arg);
+#endif
+
+static void cmd_free(struct ctlr_info *h, struct CommandList *c);
+static void cmd_special_free(struct ctlr_info *h, struct CommandList *c);
+static struct CommandList *cmd_alloc(struct ctlr_info *h);
+static struct CommandList *cmd_special_alloc(struct ctlr_info *h);
+static void fill_cmd(struct CommandList *c, __u8 cmd, struct ctlr_info *h,
+	void *buff, size_t size, __u8 page_code, unsigned char *scsi3addr,
+	int cmd_type);
+
+static int hpsa_scsi_queue_command(struct scsi_cmnd *cmd,
+		void (*done)(struct scsi_cmnd *));
+
+static int hpsa_eh_device_reset_handler(struct scsi_cmnd *scsicmd);
+static int hpsa_slave_alloc(struct scsi_device *sdev);
+static void hpsa_slave_destroy(struct scsi_device *sdev);
+
+static ssize_t raid_level_show(struct device *dev,
+	struct device_attribute *attr, char *buf);
+static ssize_t lunid_show(struct device *dev,
+	struct device_attribute *attr, char *buf);
+static ssize_t unique_id_show(struct device *dev,
+	struct device_attribute *attr, char *buf);
+static void hpsa_update_scsi_devices(struct ctlr_info *h, int hostno);
+static ssize_t host_store_rescan(struct device *dev,
+	 struct device_attribute *attr, const char *buf, size_t count);
+static int check_for_unit_attention(struct ctlr_info *h,
+	struct CommandList *c);
+static void check_ioctl_unit_attention(struct ctlr_info *h,
+	struct CommandList *c);
+
+static DEVICE_ATTR(raid_level, S_IRUGO, raid_level_show, NULL);
+static DEVICE_ATTR(lunid, S_IRUGO, lunid_show, NULL);
+static DEVICE_ATTR(unique_id, S_IRUGO, unique_id_show, NULL);
+static DEVICE_ATTR(rescan, S_IWUSR, NULL, host_store_rescan);
+
+static struct device_attribute *hpsa_sdev_attrs[] = {
+	&dev_attr_raid_level,
+	&dev_attr_lunid,
+	&dev_attr_unique_id,
+	NULL,
+};
+
+static struct device_attribute *hpsa_shost_attrs[] = {
+	&dev_attr_rescan,
+	NULL,
+};
+
+static struct scsi_host_template hpsa_driver_template = {
+	.module			= THIS_MODULE,
+	.name			= "hpsa",
+	.proc_name		= "hpsa",
+	.queuecommand		= hpsa_scsi_queue_command,
+	.can_queue		= 512,
+	.this_id		= -1,
+	.sg_tablesize		= MAXSGENTRIES,
+	.cmd_per_lun		= 512,
+	.use_clustering		= ENABLE_CLUSTERING,
+	.eh_device_reset_handler = hpsa_eh_device_reset_handler,
+	.ioctl			= hpsa_ioctl,
+	.slave_alloc		= hpsa_slave_alloc,
+	.slave_destroy		= hpsa_slave_destroy,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl		= hpsa_compat_ioctl,
+#endif
+	.sdev_attrs = hpsa_sdev_attrs,
+	.shost_attrs = hpsa_shost_attrs,
+};
+
+static inline struct ctlr_info *sdev_to_hba(struct scsi_device *sdev)
+{
+	unsigned long *priv = shost_priv(sdev->host);
+	return (struct ctlr_info *) *priv;
+}
+
+static struct task_struct *hpsa_scan_thread;
+static DEFINE_MUTEX(hpsa_scan_mutex);
+static LIST_HEAD(hpsa_scan_q);
+static int hpsa_scan_func(void *data);
+
+/**
+ * add_to_scan_list() - add controller to rescan queue
+ * @h:		      Pointer to the controller.
+ *
+ * Adds the controller to the rescan queue if not already on the queue.
+ *
+ * returns 1 if added to the queue, 0 if skipped (could be on the
+ * queue already, or the controller could be initializing or shutting
+ * down).
+ **/
+static int add_to_scan_list(struct ctlr_info *h)
+{
+	struct ctlr_info *test_h;
+	int found = 0;
+	int ret = 0;
+
+	if (h->busy_initializing)
+		return 0;
+
+	/*
+	 * If we don't get the lock, it means the driver is unloading
+	 * and there's no point in scheduling a new scan.
+	 */
+	if (!mutex_trylock(&h->busy_shutting_down))
+		return 0;
+
+	mutex_lock(&hpsa_scan_mutex);
+	list_for_each_entry(test_h, &hpsa_scan_q, scan_list) {
+		if (test_h == h) {
+			found = 1;
+			break;
+		}
+	}
+	if (!found && !h->busy_scanning) {
+		INIT_COMPLETION(h->scan_wait);
+		list_add_tail(&h->scan_list, &hpsa_scan_q);
+		ret = 1;
+	}
+	mutex_unlock(&hpsa_scan_mutex);
+	mutex_unlock(&h->busy_shutting_down);
+
+	return ret;
+}
+
+/**
+ * remove_from_scan_list() - remove controller from rescan queue
+ * @h:			   Pointer to the controller.
+ *
+ * Removes the controller from the rescan queue if present. Blocks if
+ * the controller is currently conducting a rescan.  The controller
+ * can be in one of three states:
+ * 1. Doesn't need a scan
+ * 2. On the scan list, but not scanning yet (we remove it)
+ * 3. Busy scanning (and not on the list). In this case we want to wait for
+ *    the scan to complete to make sure the scanning thread for this
+ *    controller is completely idle.
+ **/
+static void remove_from_scan_list(struct ctlr_info *h)
+{
+	struct ctlr_info *test_h, *tmp_h;
+
+	mutex_lock(&hpsa_scan_mutex);
+	list_for_each_entry_safe(test_h, tmp_h, &hpsa_scan_q, scan_list) {
+		if (test_h == h) { /* state 2. */
+			list_del(&h->scan_list);
+			complete_all(&h->scan_wait);
+			mutex_unlock(&hpsa_scan_mutex);
+			return;
+		}
+	}
+	if (h->busy_scanning) { /* state 3. */
+		mutex_unlock(&hpsa_scan_mutex);
+		wait_for_completion(&h->scan_wait);
+	} else { /* state 1, nothing to do. */
+		mutex_unlock(&hpsa_scan_mutex);
+	}
+}
+
+/* hpsa_scan_func() - kernel thread used to rescan controllers
+ * @data:	 Ignored.
+ *
+ * A kernel thread used scan for drive topology changes on
+ * controllers. The thread processes only one controller at a time
+ * using a queue.  Controllers are added to the queue using
+ * add_to_scan_list() and removed from the queue either after done
+ * processing or using remove_from_scan_list().
+ *
+ * returns 0.
+ **/
+static int hpsa_scan_func(__attribute__((unused)) void *data)
+{
+	struct ctlr_info *h;
+	int host_no;
+
+	while (1) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		schedule();
+		if (kthread_should_stop())
+			break;
+
+		while (1) {
+			mutex_lock(&hpsa_scan_mutex);
+			if (list_empty(&hpsa_scan_q)) {
+				mutex_unlock(&hpsa_scan_mutex);
+				break;
+			}
+			h = list_entry(hpsa_scan_q.next, struct ctlr_info,
+					scan_list);
+			list_del(&h->scan_list);
+			h->busy_scanning = 1;
+			mutex_unlock(&hpsa_scan_mutex);
+			host_no = h->scsi_host ?  h->scsi_host->host_no : -1;
+			hpsa_update_scsi_devices(h, host_no);
+			complete_all(&h->scan_wait);
+			mutex_lock(&hpsa_scan_mutex);
+			h->busy_scanning = 0;
+			mutex_unlock(&hpsa_scan_mutex);
+		}
+	}
+	return 0;
+}
+
+static int check_for_unit_attention(struct ctlr_info *h,
+	struct CommandList *c)
+{
+	if (c->err_info->SenseInfo[2] != UNIT_ATTENTION)
+		return 0;
+
+	switch (c->err_info->SenseInfo[12]) {
+	case STATE_CHANGED:
+		dev_warn(&h->pdev->dev, "hpsa%d: a state change "
+			"detected, command retried\n", h->ctlr);
+		break;
+	case LUN_FAILED:
+		dev_warn(&h->pdev->dev, "hpsa%d: LUN failure "
+			"detected, action required\n", h->ctlr);
+		break;
+	case REPORT_LUNS_CHANGED:
+		dev_warn(&h->pdev->dev, "hpsa%d: report LUN data "
+			"changed\n", h->ctlr);
+	/*
+	 * Here, we could call add_to_scan_list and wake up the scan thread,
+	 * except that it's quite likely that we will get more than one
+	 * REPORT_LUNS_CHANGED condition in quick succession, which means
+	 * that those which occur after the first one will likely happen
+	 * *during* the hpsa_scan_thread's rescan.  And the rescan code is not
+	 * robust enough to restart in the middle, undoing what it has already
+	 * done, and it's not clear that it's even possible to do this, since
+	 * part of what it does is notify the SCSI mid layer, which starts
+	 * doing it's own i/o to read partition tables and so on, and the
+	 * driver doesn't have visibility to know what might need undoing.
+	 * In any event, if possible, it is horribly complicated to get right
+	 * so we just don't do it for now.
+	 *
+	 * Note: this REPORT_LUNS_CHANGED condition only occurs on the MSA2012.
+	 */
+		break;
+	case POWER_OR_RESET:
+		dev_warn(&h->pdev->dev, "hpsa%d: a power on "
+			"or device reset detected\n", h->ctlr);
+		break;
+	case UNIT_ATTENTION_CLEARED:
+		dev_warn(&h->pdev->dev, "hpsa%d: unit attention "
+		    "cleared by another initiator\n", h->ctlr);
+		break;
+	default:
+		dev_warn(&h->pdev->dev, "hpsa%d: unknown "
+			"unit attention detected\n", h->ctlr);
+		break;
+	}
+	return 1;
+}
+
+static ssize_t host_store_rescan(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct ctlr_info *h;
+	struct Scsi_Host *shost = class_to_shost(dev);
+	unsigned long *priv = shost_priv(shost);
+	h = (struct ctlr_info *) *priv;
+	if (add_to_scan_list(h)) {
+		wake_up_process(hpsa_scan_thread);
+		wait_for_completion_interruptible(&h->scan_wait);
+	}
+	return count;
+}
+
+/* Enqueuing and dequeuing functions for cmdlists. */
+static inline void addQ(struct hlist_head *list, struct CommandList *c)
+{
+	hlist_add_head(&c->list, list);
+}
+
+static void enqueue_cmd_and_start_io(struct ctlr_info *h,
+	struct CommandList *c)
+{
+	unsigned long flags;
+	spin_lock_irqsave(&h->lock, flags);
+	addQ(&h->reqQ, c);
+	h->Qdepth++;
+	start_io(h);
+	spin_unlock_irqrestore(&h->lock, flags);
+}
+
+static inline void removeQ(struct CommandList *c)
+{
+	if (WARN_ON(hlist_unhashed(&c->list)))
+		return;
+	hlist_del_init(&c->list);
+}
+
+static inline int is_hba_lunid(unsigned char scsi3addr[])
+{
+	return memcmp(scsi3addr, RAID_CTLR_LUNID, 8) == 0;
+}
+
+static inline int is_logical_dev_addr_mode(unsigned char scsi3addr[])
+{
+	return (scsi3addr[3] & 0xC0) == 0x40;
+}
+
+static const char *raid_label[] = { "0", "4", "1(1+0)", "5", "5+1", "ADG",
+	"UNKNOWN"
+};
+#define RAID_UNKNOWN (ARRAY_SIZE(raid_label) - 1)
+
+static ssize_t raid_level_show(struct device *dev,
+	     struct device_attribute *attr, char *buf)
+{
+	ssize_t l = 0;
+	int rlevel;
+	struct ctlr_info *h;
+	struct scsi_device *sdev;
+	struct hpsa_scsi_dev_t *hdev;
+	unsigned long flags;
+
+	sdev = to_scsi_device(dev);
+	h = sdev_to_hba(sdev);
+	spin_lock_irqsave(&h->lock, flags);
+	hdev = sdev->hostdata;
+	if (!hdev) {
+		spin_unlock_irqrestore(&h->lock, flags);
+		return -ENODEV;
+	}
+
+	/* Is this even a logical drive? */
+	if (!is_logical_dev_addr_mode(hdev->scsi3addr)) {
+		spin_unlock_irqrestore(&h->lock, flags);
+		l = snprintf(buf, PAGE_SIZE, "N/A\n");
+		return l;
+	}
+
+	rlevel = hdev->raid_level;
+	spin_unlock_irqrestore(&h->lock, flags);
+	if (rlevel < 0 || rlevel > RAID_UNKNOWN)
+		rlevel = RAID_UNKNOWN;
+	l = snprintf(buf, PAGE_SIZE, "RAID %s\n", raid_label[rlevel]);
+	return l;
+}
+
+static ssize_t lunid_show(struct device *dev,
+	     struct device_attribute *attr, char *buf)
+{
+	struct ctlr_info *h;
+	struct scsi_device *sdev;
+	struct hpsa_scsi_dev_t *hdev;
+	unsigned long flags;
+	unsigned char lunid[8];
+
+	sdev = to_scsi_device(dev);
+	h = sdev_to_hba(sdev);
+	spin_lock_irqsave(&h->lock, flags);
+	hdev = sdev->hostdata;
+	if (!hdev) {
+		spin_unlock_irqrestore(&h->lock, flags);
+		return -ENODEV;
+	}
+	memcpy(lunid, hdev->scsi3addr, sizeof(lunid));
+	spin_unlock_irqrestore(&h->lock, flags);
+	return snprintf(buf, 20, "0x%02x%02x%02x%02x%02x%02x%02x%02x\n",
+		lunid[0], lunid[1], lunid[2], lunid[3],
+		lunid[4], lunid[5], lunid[6], lunid[7]);
+}
+
+static ssize_t unique_id_show(struct device *dev,
+	     struct device_attribute *attr, char *buf)
+{
+	struct ctlr_info *h;
+	struct scsi_device *sdev;
+	struct hpsa_scsi_dev_t *hdev;
+	unsigned long flags;
+	unsigned char sn[16];
+
+	sdev = to_scsi_device(dev);
+	h = sdev_to_hba(sdev);
+	spin_lock_irqsave(&h->lock, flags);
+	hdev = sdev->hostdata;
+	if (!hdev) {
+		spin_unlock_irqrestore(&h->lock, flags);
+		return -ENODEV;
+	}
+	memcpy(sn, hdev->device_id, sizeof(sn));
+	spin_unlock_irqrestore(&h->lock, flags);
+	return snprintf(buf, 16 * 2 + 2,
+			"%02X%02X%02X%02X%02X%02X%02X%02X"
+			"%02X%02X%02X%02X%02X%02X%02X%02X\n",
+			sn[0], sn[1], sn[2], sn[3],
+			sn[4], sn[5], sn[6], sn[7],
+			sn[8], sn[9], sn[10], sn[11],
+			sn[12], sn[13], sn[14], sn[15]);
+}
+
+static int hpsa_find_target_lun(struct ctlr_info *h,
+	unsigned char scsi3addr[], int bus, int *target, int *lun)
+{
+	/* finds an unused bus, target, lun for a new physical device
+	 * assumes h->devlock is held
+	 */
+	int i, found = 0;
+	DECLARE_BITMAP(lun_taken, HPSA_MAX_SCSI_DEVS_PER_HBA);
+
+	memset(&lun_taken[0], 0, HPSA_MAX_SCSI_DEVS_PER_HBA >> 3);
+
+	for (i = 0; i < h->ndevices; i++) {
+		if (h->dev[i]->bus == bus && h->dev[i]->target != -1)
+			set_bit(h->dev[i]->target, lun_taken);
+	}
+
+	for (i = 0; i < HPSA_MAX_SCSI_DEVS_PER_HBA; i++) {
+		if (!test_bit(i, lun_taken)) {
+			/* *bus = 1; */
+			*target = i;
+			*lun = 0;
+			found = 1;
+			break;
+		}
+	}
+	return !found;
+}
+
+/* Add an entry into h->dev[] array. */
+static int hpsa_scsi_add_entry(struct ctlr_info *h, int hostno,
+		struct hpsa_scsi_dev_t *device,
+		struct hpsa_scsi_dev_t *added[], int *nadded)
+{
+	/* assumes h->devlock is held */
+	int n = h->ndevices;
+	int i;
+	unsigned char addr1[8], addr2[8];
+	struct hpsa_scsi_dev_t *sd;
+
+	if (n >= HPSA_MAX_SCSI_DEVS_PER_HBA) {
+		dev_err(&h->pdev->dev, "too many devices, some will be "
+			"inaccessible.\n");
+		return -1;
+	}
+
+	/* physical devices do not have lun or target assigned until now. */
+	if (device->lun != -1)
+		/* Logical device, lun is already assigned. */
+		goto lun_assigned;
+
+	/* If this device a non-zero lun of a multi-lun device
+	 * byte 4 of the 8-byte LUN addr will contain the logical
+	 * unit no, zero otherise.
+	 */
+	if (device->scsi3addr[4] == 0) {
+		/* This is not a non-zero lun of a multi-lun device */
+		if (hpsa_find_target_lun(h, device->scsi3addr,
+			device->bus, &device->target, &device->lun) != 0)
+			return -1;
+		goto lun_assigned;
+	}
+
+	/* This is a non-zero lun of a multi-lun device.
+	 * Search through our list and find the device which
+	 * has the same 8 byte LUN address, excepting byte 4.
+	 * Assign the same bus and target for this new LUN.
+	 * Use the logical unit number from the firmware.
+	 */
+	memcpy(addr1, device->scsi3addr, 8);
+	addr1[4] = 0;
+	for (i = 0; i < n; i++) {
+		sd = h->dev[i];
+		memcpy(addr2, sd->scsi3addr, 8);
+		addr2[4] = 0;
+		/* differ only in byte 4? */
+		if (memcmp(addr1, addr2, 8) == 0) {
+			device->bus = sd->bus;
+			device->target = sd->target;
+			device->lun = device->scsi3addr[4];
+			break;
+		}
+	}
+	if (device->lun == -1) {
+		dev_warn(&h->pdev->dev, "physical device with no LUN=0,"
+			" suspect firmware bug or unsupported hardware "
+			"configuration.\n");
+			return -1;
+	}
+
+lun_assigned:
+
+	h->dev[n] = device;
+	h->ndevices++;
+	added[*nadded] = device;
+	(*nadded)++;
+
+	/* initially, (before registering with scsi layer) we don't
+	 * know our hostno and we don't want to print anything first
+	 * time anyway (the scsi layer's inquiries will show that info)
+	 */
+	/* if (hostno != -1) */
+		dev_info(&h->pdev->dev, "%s device c%db%dt%dl%d added.\n",
+			scsi_device_type(device->devtype), hostno,
+			device->bus, device->target, device->lun);
+	return 0;
+}
+
+/* Remove an entry from h->dev[] array. */
+static void hpsa_scsi_remove_entry(struct ctlr_info *h, int hostno, int entry,
+	struct hpsa_scsi_dev_t *removed[], int *nremoved)
+{
+	/* assumes h->devlock is held */
+	int i;
+	struct hpsa_scsi_dev_t *sd;
+
+	if (entry < 0 || entry >= HPSA_MAX_SCSI_DEVS_PER_HBA)
+		BUG();
+
+	sd = h->dev[entry];
+	removed[*nremoved] = h->dev[entry];
+	(*nremoved)++;
+
+	for (i = entry; i < h->ndevices-1; i++)
+		h->dev[i] = h->dev[i+1];
+	h->ndevices--;
+	dev_info(&h->pdev->dev, "%s device c%db%dt%dl%d removed.\n",
+		scsi_device_type(sd->devtype), hostno, sd->bus, sd->target,
+		sd->lun);
+}
+
+#define SCSI3ADDR_EQ(a, b) ( \
+	(a)[7] == (b)[7] && \
+	(a)[6] == (b)[6] && \
+	(a)[5] == (b)[5] && \
+	(a)[4] == (b)[4] && \
+	(a)[3] == (b)[3] && \
+	(a)[2] == (b)[2] && \
+	(a)[1] == (b)[1] && \
+	(a)[0] == (b)[0])
+
+static void fixup_botched_add(struct ctlr_info *h,
+	struct hpsa_scsi_dev_t *added)
+{
+	/* called when scsi_add_device fails in order to re-adjust
+	 * h->dev[] to match the mid layer's view.
+	 */
+	unsigned long flags;
+	int i, j;
+
+	spin_lock_irqsave(&h->lock, flags);
+	for (i = 0; i < h->ndevices; i++) {
+		if (h->dev[i] == added) {
+			for (j = i; j < h->ndevices-1; j++)
+				h->dev[j] = h->dev[j+1];
+			h->ndevices--;
+			break;
+		}
+	}
+	spin_unlock_irqrestore(&h->lock, flags);
+	kfree(added);
+}
+
+static inline int device_is_the_same(struct hpsa_scsi_dev_t *dev1,
+	struct hpsa_scsi_dev_t *dev2)
+{
+	if ((is_logical_dev_addr_mode(dev1->scsi3addr) ||
+		(dev1->lun != -1 && dev2->lun != -1)) &&
+		dev1->devtype != 0x0C)
+		return (memcmp(dev1, dev2, sizeof(*dev1)) == 0);
+
+	/* we compare everything except lun and target as these
+	 * are not yet assigned.  Compare parts likely
+	 * to differ first
+	 */
+	if (memcmp(dev1->scsi3addr, dev2->scsi3addr,
+		sizeof(dev1->scsi3addr)) != 0)
+		return 0;
+	if (memcmp(dev1->device_id, dev2->device_id,
+		sizeof(dev1->device_id)) != 0)
+		return 0;
+	if (memcmp(dev1->model, dev2->model, sizeof(dev1->model)) != 0)
+		return 0;
+	if (memcmp(dev1->vendor, dev2->vendor, sizeof(dev1->vendor)) != 0)
+		return 0;
+	if (memcmp(dev1->revision, dev2->revision, sizeof(dev1->revision)) != 0)
+		return 0;
+	if (dev1->devtype != dev2->devtype)
+		return 0;
+	if (dev1->raid_level != dev2->raid_level)
+		return 0;
+	if (dev1->bus != dev2->bus)
+		return 0;
+	return 1;
+}
+
+/* Find needle in haystack.  If exact match found, return DEVICE_SAME,
+ * and return needle location in *index.  If scsi3addr matches, but not
+ * vendor, model, serial num, etc. return DEVICE_CHANGED, and return needle
+ * location in *index.  If needle not found, return DEVICE_NOT_FOUND.
+ */
+static int hpsa_scsi_find_entry(struct hpsa_scsi_dev_t *needle,
+	struct hpsa_scsi_dev_t *haystack[], int haystack_size,
+	int *index)
+{
+	int i;
+#define DEVICE_NOT_FOUND 0
+#define DEVICE_CHANGED 1
+#define DEVICE_SAME 2
+	for (i = 0; i < haystack_size; i++) {
+		if (SCSI3ADDR_EQ(needle->scsi3addr, haystack[i]->scsi3addr)) {
+			*index = i;
+			if (device_is_the_same(needle, haystack[i]))
+				return DEVICE_SAME;
+			else
+				return DEVICE_CHANGED;
+		}
+	}
+	*index = -1;
+	return DEVICE_NOT_FOUND;
+}
+
+static int adjust_hpsa_scsi_table(struct ctlr_info *h, int hostno,
+	struct hpsa_scsi_dev_t *sd[], int nsds)
+{
+	/* sd contains scsi3 addresses and devtypes, and inquiry
+	 * data.  This function takes what's in sd to be the current
+	 * reality and updates h->dev[] to reflect that reality.
+	 */
+	int i, entry, device_change, changes = 0;
+	struct hpsa_scsi_dev_t *csd;
+	unsigned long flags;
+	struct hpsa_scsi_dev_t **added, **removed;
+	int nadded, nremoved;
+	struct Scsi_Host *sh = NULL;
+
+	added = kzalloc(sizeof(*added) * HPSA_MAX_SCSI_DEVS_PER_HBA,
+		GFP_KERNEL);
+	removed = kzalloc(sizeof(*removed) * HPSA_MAX_SCSI_DEVS_PER_HBA,
+		GFP_KERNEL);
+
+	if (!added || !removed) {
+		dev_warn(&h->pdev->dev, "out of memory in "
+			"adjust_hpsa_scsi_table\n");
+		goto free_and_out;
+	}
+
+	spin_lock_irqsave(&h->devlock, flags);
+
+	/* find any devices in h->dev[] that are not in
+	 * sd[] and remove them from h->dev[], and for any
+	 * devices which have changed, remove the old device
+	 * info and add the new device info.
+	 */
+	i = 0;
+	nremoved = 0;
+	nadded = 0;
+	while (i < h->ndevices) {
+		csd = h->dev[i];
+		device_change = hpsa_scsi_find_entry(csd, sd, nsds, &entry);
+		if (device_change == DEVICE_NOT_FOUND) {
+			changes++;
+			hpsa_scsi_remove_entry(h, hostno, i,
+				removed, &nremoved);
+			continue; /* remove ^^^, hence i not incremented */
+		} else if (device_change == DEVICE_CHANGED) {
+			changes++;
+			hpsa_scsi_remove_entry(h, hostno, i,
+				removed, &nremoved);
+			(void) hpsa_scsi_add_entry(h, hostno, sd[entry],
+				added, &nadded);
+			/* add can't fail, we just removed one. */
+			sd[entry] = NULL; /* prevent it from being freed */
+		}
+		i++;
+	}
+
+	/* Now, make sure every device listed in sd[] is also
+	 * listed in h->dev[], adding them if they aren't found
+	 */
+
+	for (i = 0; i < nsds; i++) {
+		if (!sd[i]) /* if already added above. */
+			continue;
+		device_change = hpsa_scsi_find_entry(sd[i], h->dev,
+					h->ndevices, &entry);
+		if (device_change == DEVICE_NOT_FOUND) {
+			changes++;
+			if (hpsa_scsi_add_entry(h, hostno, sd[i],
+				added, &nadded) != 0)
+				break;
+			sd[i] = NULL; /* prevent from being freed later. */
+		} else if (device_change == DEVICE_CHANGED) {
+			/* should never happen... */
+			changes++;
+			dev_warn(&h->pdev->dev,
+				"device unexpectedly changed.\n");
+			/* but if it does happen, we just ignore that device */
+		}
+	}
+	spin_unlock_irqrestore(&h->devlock, flags);
+
+	/* Don't notify scsi mid layer of any changes the first time through
+	 * (or if there are no changes) scsi_scan_host will do it later the
+	 * first time through.
+	 */
+	if (hostno == -1 || !changes)
+		goto free_and_out;
+
+	sh = h->scsi_host;
+	/* Notify scsi mid layer of any removed devices */
+	for (i = 0; i < nremoved; i++) {
+		struct scsi_device *sdev =
+			scsi_device_lookup(sh, removed[i]->bus,
+				removed[i]->target, removed[i]->lun);
+		if (sdev != NULL) {
+			scsi_remove_device(sdev);
+			scsi_device_put(sdev);
+		} else {
+			/* We don't expect to get here.
+			 * future cmds to this device will get selection
+			 * timeout as if the device was gone.
+			 */
+			dev_warn(&h->pdev->dev, "didn't find c%db%dt%dl%d "
+				" for removal.", hostno, removed[i]->bus,
+				removed[i]->target, removed[i]->lun);
+		}
+		kfree(removed[i]);
+		removed[i] = NULL;
+	}
+
+	/* Notify scsi mid layer of any added devices */
+	for (i = 0; i < nadded; i++) {
+		if (scsi_add_device(sh, added[i]->bus,
+			added[i]->target, added[i]->lun) == 0)
+			continue;
+		dev_warn(&h->pdev->dev, "scsi_add_device c%db%dt%dl%d failed, "
+			"device not added.\n", hostno, added[i]->bus,
+			added[i]->target, added[i]->lun);
+		/* now we have to remove it from h->dev,
+		 * since it didn't get added to scsi mid layer
+		 */
+		fixup_botched_add(h, added[i]);
+	}
+
+free_and_out:
+	kfree(added);
+	kfree(removed);
+	return 0;
+}
+
+/*
+ * Lookup bus/target/lun and retrun corresponding struct hpsa_scsi_dev_t *
+ * Assume's h->devlock is held.
+ */
+static struct hpsa_scsi_dev_t *lookup_hpsa_scsi_dev(struct ctlr_info *h,
+	int bus, int target, int lun)
+{
+	int i;
+	struct hpsa_scsi_dev_t *sd;
+
+	for (i = 0; i < h->ndevices; i++) {
+		sd = h->dev[i];
+		if (sd->bus == bus && sd->target == target && sd->lun == lun)
+			return sd;
+	}
+	return NULL;
+}
+
+/* link sdev->hostdata to our per-device structure. */
+static int hpsa_slave_alloc(struct scsi_device *sdev)
+{
+	struct hpsa_scsi_dev_t *sd;
+	unsigned long flags;
+	struct ctlr_info *h;
+
+	h = sdev_to_hba(sdev);
+	spin_lock_irqsave(&h->devlock, flags);
+	sd = lookup_hpsa_scsi_dev(h, sdev_channel(sdev),
+		sdev_id(sdev), sdev->lun);
+	if (sd != NULL)
+		sdev->hostdata = sd;
+	spin_unlock_irqrestore(&h->devlock, flags);
+	return 0;
+}
+
+static void hpsa_slave_destroy(struct scsi_device *sdev)
+{
+	return; /* nothing to do. */
+}
+
+static void hpsa_scsi_setup(struct ctlr_info *h)
+{
+	h->ndevices = 0;
+	h->scsi_host = NULL;
+	spin_lock_init(&h->devlock);
+	return;
+}
+
+static void complete_scsi_command(struct CommandList *cp,
+	int timeout, __u32 tag)
+{
+	struct scsi_cmnd *cmd;
+	struct ctlr_info *h;
+	struct ErrorInfo *ei;
+
+	unsigned char sense_key;
+	unsigned char asc;      /* additional sense code */
+	unsigned char ascq;     /* additional sense code qualifier */
+
+	ei = cp->err_info;
+	cmd = (struct scsi_cmnd *) cp->scsi_cmd;
+	h = cp->h;
+
+	scsi_dma_unmap(cmd); /* undo the DMA mappings */
+
+	cmd->result = (DID_OK << 16); 		/* host byte */
+	cmd->result |= (COMMAND_COMPLETE << 8);	/* msg byte */
+	cmd->result |= (ei->ScsiStatus << 1);
+
+	/* copy the sense data whether we need to or not. */
+	memcpy(cmd->sense_buffer, ei->SenseInfo,
+		ei->SenseLen > SCSI_SENSE_BUFFERSIZE ?
+			SCSI_SENSE_BUFFERSIZE :
+			ei->SenseLen);
+	scsi_set_resid(cmd, ei->ResidualCnt);
+
+	if (ei->CommandStatus == 0) {
+		cmd->scsi_done(cmd);
+		cmd_free(h, cp);
+		return;
+	}
+
+	/* an error has occurred */
+	switch (ei->CommandStatus) {
+
+	case CMD_TARGET_STATUS:
+		if (ei->ScsiStatus) {
+			/* Get sense key */
+			sense_key = 0xf & ei->SenseInfo[2];
+			/* Get additional sense code */
+			asc = ei->SenseInfo[12];
+			/* Get addition sense code qualifier */
+			ascq = ei->SenseInfo[13];
+		}
+
+		if (ei->ScsiStatus == SAM_STAT_CHECK_CONDITION) {
+			if (check_for_unit_attention(h, cp)) {
+				cmd->result = DID_SOFT_ERROR << 16;
+				break;
+			}
+			if (sense_key == ILLEGAL_REQUEST) {
+				/*
+				 * SCSI REPORT_LUNS is commonly unsupported on
+				 * Smart Array.  Suppress noisy complaint.
+				 */
+				if (cp->Request.CDB[0] == REPORT_LUNS)
+					break;
+
+				/* If ASC/ASCQ indicate Logical Unit
+				 * Not Supported condition,
+				 */
+				if ((asc == 0x25) && (ascq == 0x0)) {
+					dev_warn(&h->pdev->dev, "cp %p "
+						"has check condition\n", cp);
+					break;
+				}
+			}
+
+			if (sense_key == NOT_READY) {
+				/* If Sense is Not Ready, Logical Unit
+				 * Not ready, Manual Intervention
+				 * required
+				 */
+				if ((asc == 0x04) && (ascq == 0x03)) {
+					cmd->result = DID_NO_CONNECT << 16;
+					dev_warn(&h->pdev->dev, "cp %p "
+						"has check condition: unit "
+						"not ready, manual "
+						"intervention required\n", cp);
+					break;
+				}
+			}
+
+
+			/* Must be some other type of check condition */
+			dev_warn(&h->pdev->dev, "cp %p has check condition: "
+					"unknown type: "
+					"Sense: 0x%x, ASC: 0x%x, ASCQ: 0x%x, "
+					"Returning result: 0x%x, "
+					"cmd=[%02x %02x %02x %02x %02x "
+					"%02x %02x %02x %02x %02x]\n",
+					cp, sense_key, asc, ascq,
+					cmd->result,
+					cmd->cmnd[0], cmd->cmnd[1],
+					cmd->cmnd[2], cmd->cmnd[3],
+					cmd->cmnd[4], cmd->cmnd[5],
+					cmd->cmnd[6], cmd->cmnd[7],
+					cmd->cmnd[8], cmd->cmnd[9]);
+			break;
+		}
+
+
+		/* Problem was not a check condition