1 files changed, 431 insertions, 0 deletions
diff --git a/drivers/scsi/device_handler/scsi_dh_hp_sw.c b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
new file mode 100644
index 00000000..084062bb
--- /dev/null
+++ b/drivers/scsi/device_handler/scsi_dh_hp_sw.c
@@ -0,0 +1,431 @@
+/*
+ * 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
+ * Copyright (C) 2008 Hannes Reinecke <hare@suse.de>
+ *
+ * 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/slab.h>
+#include <linux/module.h>
+#include <scsi/scsi.h>
+#include <scsi/scsi_dbg.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dh.h>
+
+#define HP_SW_NAME			"hp_sw"
+
+#define HP_SW_TIMEOUT			(60 * HZ)
+#define HP_SW_RETRIES			3
+
+#define HP_SW_PATH_UNINITIALIZED	-1
+#define HP_SW_PATH_ACTIVE		0
+#define HP_SW_PATH_PASSIVE		1
+
+struct hp_sw_dh_data {
+	unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+	int path_state;
+	int retries;
+	int retry_cnt;
+	struct scsi_device *sdev;
+	activate_complete	callback_fn;
+	void			*callback_data;
+};
+
+static int hp_sw_start_stop(struct hp_sw_dh_data *);
+
+static inline struct hp_sw_dh_data *get_hp_sw_data(struct scsi_device *sdev)
+{
+	struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
+	BUG_ON(scsi_dh_data == NULL);
+	return ((struct hp_sw_dh_data *) scsi_dh_data->buf);
+}
+
+/*
+ * tur_done - Handle TEST UNIT READY return status
+ * @sdev: sdev the command has been sent to
+ * @errors: blk error code
+ *
+ * Returns SCSI_DH_DEV_OFFLINED if the sdev is on the passive path
+ */
+static int tur_done(struct scsi_device *sdev, unsigned char *sense)
+{
+	struct scsi_sense_hdr sshdr;
+	int ret;
+
+	ret = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
+	if (!ret) {
+		sdev_printk(KERN_WARNING, sdev,
+			    "%s: sending tur failed, no sense available\n",
+			    HP_SW_NAME);
+		ret = SCSI_DH_IO;
+		goto done;
+	}
+	switch (sshdr.sense_key) {
+	case UNIT_ATTENTION:
+		ret = SCSI_DH_IMM_RETRY;
+		break;
+	case NOT_READY:
+		if ((sshdr.asc == 0x04) && (sshdr.ascq == 2)) {
+			/*
+			 * LUN not ready - Initialization command required
+			 *
+			 * This is the passive path
+			 */
+			ret = SCSI_DH_DEV_OFFLINED;
+			break;
+		}
+		/* Fallthrough */
+	default:
+		sdev_printk(KERN_WARNING, sdev,
+			   "%s: sending tur failed, sense %x/%x/%x\n",
+			   HP_SW_NAME, sshdr.sense_key, sshdr.asc,
+			   sshdr.ascq);
+		break;
+	}
+
+done:
+	return ret;
+}
+
+/*
+ * hp_sw_tur - Send TEST UNIT READY
+ * @sdev: sdev command should be sent to
+ *
+ * Use the TEST UNIT READY command to determine
+ * the path state.
+ */
+static int hp_sw_tur(struct scsi_device *sdev, struct hp_sw_dh_data *h)
+{
+	struct request *req;
+	int ret;
+
+retry:
+	req = blk_get_request(sdev->request_queue, WRITE, GFP_NOIO);
+	if (!req)
+		return SCSI_DH_RES_TEMP_UNAVAIL;
+
+	req->cmd_type = REQ_TYPE_BLOCK_PC;
+	req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+			  REQ_FAILFAST_DRIVER;
+	req->cmd_len = COMMAND_SIZE(TEST_UNIT_READY);
+	req->cmd[0] = TEST_UNIT_READY;
+	req->timeout = HP_SW_TIMEOUT;
+	req->sense = h->sense;
+	memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+	req->sense_len = 0;
+
+	ret = blk_execute_rq(req->q, NULL, req, 1);
+	if (ret == -EIO) {
+		if (req->sense_len > 0) {
+			ret = tur_done(sdev, h->sense);
+		} else {
+			sdev_printk(KERN_WARNING, sdev,
+				    "%s: sending tur failed with %x\n",
+				    HP_SW_NAME, req->errors);
+			ret = SCSI_DH_IO;
+		}
+	} else {
+		h->path_state = HP_SW_PATH_ACTIVE;
+		ret = SCSI_DH_OK;
+	}
+	if (ret == SCSI_DH_IMM_RETRY) {
+		blk_put_request(req);
+		goto retry;
+	}
+	if (ret == SCSI_DH_DEV_OFFLINED) {
+		h->path_state = HP_SW_PATH_PASSIVE;
+		ret = SCSI_DH_OK;
+	}
+
+	blk_put_request(req);
+
+	return ret;
+}
+
+/*
+ * start_done - Handle START STOP UNIT return status
+ * @sdev: sdev the command has been sent to
+ * @errors: blk error code
+ */
+static int start_done(struct scsi_device *sdev, unsigned char *sense)
+{
+	struct scsi_sense_hdr sshdr;
+	int rc;
+
+	rc = scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr);
+	if (!rc) {
+		sdev_printk(KERN_WARNING, sdev,
+			    "%s: sending start_stop_unit failed, "
+			    "no sense available\n",
+			    HP_SW_NAME);
+		return SCSI_DH_IO;
+	}
+	switch (sshdr.sense_key) {
+	case NOT_READY:
+		if ((sshdr.asc == 0x04) && (sshdr.ascq == 3)) {
+			/*
+			 * LUN not ready - manual intervention required
+			 *
+			 * Switch-over in progress, retry.
+			 */
+			rc = SCSI_DH_RETRY;
+			break;
+		}
+		/* fall through */
+	default:
+		sdev_printk(KERN_WARNING, sdev,
+			   "%s: sending start_stop_unit failed, sense %x/%x/%x\n",
+			   HP_SW_NAME, sshdr.sense_key, sshdr.asc,
+			   sshdr.ascq);
+		rc = SCSI_DH_IO;
+	}
+
+	return rc;
+}
+
+static void start_stop_endio(struct request *req, int error)
+{
+	struct hp_sw_dh_data *h = req->end_io_data;
+	unsigned err = SCSI_DH_OK;
+
+	if (error || host_byte(req->errors) != DID_OK ||
+			msg_byte(req->errors) != COMMAND_COMPLETE) {
+		sdev_printk(KERN_WARNING, h->sdev,
+			    "%s: sending start_stop_unit failed with %x\n",
+			    HP_SW_NAME, req->errors);
+		err = SCSI_DH_IO;
+		goto done;
+	}
+
+	if (req->sense_len > 0) {
+		err = start_done(h->sdev, h->sense);
+		if (err == SCSI_DH_RETRY) {
+			err = SCSI_DH_IO;
+			if (--h->retry_cnt) {
+				blk_put_request(req);
+				err = hp_sw_start_stop(h);
+				if (err == SCSI_DH_OK)
+					return;
+			}
+		}
+	}
+done:
+	req->end_io_data = NULL;
+	__blk_put_request(req->q, req);
+	if (h->callback_fn) {
+		h->callback_fn(h->callback_data, err);
+		h->callback_fn = h->callback_data = NULL;
+	}
+	return;
+
+}
+
+/*
+ * hp_sw_start_stop - Send START STOP UNIT command
+ * @sdev: sdev command should be sent to
+ *
+ * Sending START STOP UNIT activates the SP.
+ */
+static int hp_sw_start_stop(struct hp_sw_dh_data *h)
+{
+	struct request *req;
+
+	req = blk_get_request(h->sdev->request_queue, WRITE, GFP_ATOMIC);
+	if (!req)
+		return SCSI_DH_RES_TEMP_UNAVAIL;
+
+	req->cmd_type = REQ_TYPE_BLOCK_PC;
+	req->cmd_flags |= REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT |
+			  REQ_FAILFAST_DRIVER;
+	req->cmd_len = COMMAND_SIZE(START_STOP);
+	req->cmd[0] = START_STOP;
+	req->cmd[4] = 1;	/* Start spin cycle */
+	req->timeout = HP_SW_TIMEOUT;
+	req->sense = h->sense;
+	memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+	req->sense_len = 0;
+	req->end_io_data = h;
+
+	blk_execute_rq_nowait(req->q, NULL, req, 1, start_stop_endio);
+	return SCSI_DH_OK;
+}
+
+static int hp_sw_prep_fn(struct scsi_device *sdev, struct request *req)
+{
+	struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
+	int ret = BLKPREP_OK;
+
+	if (h->path_state != HP_SW_PATH_ACTIVE) {
+		ret = BLKPREP_KILL;
+		req->cmd_flags |= REQ_QUIET;
+	}
+	return ret;
+
+}
+
+/*
+ * hp_sw_activate - Activate a path
+ * @sdev: sdev on the path to be activated
+ *
+ * The HP Active/Passive firmware is pretty simple;
+ * the passive path reports NOT READY with sense codes
+ * 0x04/0x02; a START STOP UNIT command will then
+ * activate the passive path (and deactivate the
+ * previously active one).
+ */
+static int hp_sw_activate(struct scsi_device *sdev,
+				activate_complete fn, void *data)
+{
+	int ret = SCSI_DH_OK;
+	struct hp_sw_dh_data *h = get_hp_sw_data(sdev);
+
+	ret = hp_sw_tur(sdev, h);
+
+	if (ret == SCSI_DH_OK && h->path_state == HP_SW_PATH_PASSIVE) {
+		h->retry_cnt = h->retries;
+		h->callback_fn = fn;
+		h->callback_data = data;
+		ret = hp_sw_start_stop(h);
+		if (ret == SCSI_DH_OK)
+			return 0;
+		h->callback_fn = h->callback_data = NULL;
+	}
+
+	if (fn)
+		fn(data, ret);
+	return 0;
+}
+
+static const struct scsi_dh_devlist hp_sw_dh_data_list[] = {
+	{"COMPAQ", "MSA1000 VOLUME"},
+	{"COMPAQ", "HSV110"},
+	{"HP", "HSV100"},
+	{"DEC", "HSG80"},
+	{NULL, NULL},
+};
+
+static bool hp_sw_match(struct scsi_device *sdev)
+{
+	int i;
+
+	if (scsi_device_tpgs(sdev))
+		return false;
+
+	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))) {
+			return true;
+		}
+	}
+	return false;
+}
+
+static int hp_sw_bus_attach(struct scsi_device *sdev);
+static void hp_sw_bus_detach(struct scsi_device *sdev);
+
+static struct scsi_device_handler hp_sw_dh = {
+	.name		= HP_SW_NAME,
+	.module		= THIS_MODULE,
+	.devlist	= hp_sw_dh_data_list,
+	.attach		= hp_sw_bus_attach,
+	.detach		= hp_sw_bus_detach,
+	.activate	= hp_sw_activate,
+	.prep_fn	= hp_sw_prep_fn,
+	.match		= hp_sw_match,
+};
+
+static int hp_sw_bus_attach(struct scsi_device *sdev)
+{
+	struct scsi_dh_data *scsi_dh_data;
+	struct hp_sw_dh_data *h;
+	unsigned long flags;
+	int ret;
+
+	scsi_dh_data = kzalloc(sizeof(*scsi_dh_data)
+			       + sizeof(*h) , GFP_KERNEL);
+	if (!scsi_dh_data) {
+		sdev_printk(KERN_ERR, sdev, "%s: Attach Failed\n",
+			    HP_SW_NAME);
+		return 0;
+	}
+
+	scsi_dh_data->scsi_dh = &hp_sw_dh;
+	h = (struct hp_sw_dh_data *) scsi_dh_data->buf;
+	h->path_state = HP_SW_PATH_UNINITIALIZED;
+	h->retries = HP_SW_RETRIES;
+	h->sdev = sdev;
+
+	ret = hp_sw_tur(sdev, h);
+	if (ret != SCSI_DH_OK || h->path_state == HP_SW_PATH_UNINITIALIZED)
+		goto failed;
+
+	if (!try_module_get(THIS_MODULE))
+		goto failed;
+
+	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+	sdev->scsi_dh_data = scsi_dh_data;
+	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+	sdev_printk(KERN_INFO, sdev, "%s: attached to %s path\n",
+		    HP_SW_NAME, h->path_state == HP_SW_PATH_ACTIVE?
+		    "active":"passive");
+
+	return 0;
+
+failed:
+	kfree(scsi_dh_data);
+	sdev_printk(KERN_ERR, sdev, "%s: not attached\n",
+		    HP_SW_NAME);
+	return -EINVAL;
+}
+
+static void hp_sw_bus_detach( struct scsi_device *sdev )
+{
+	struct scsi_dh_data *scsi_dh_data;
+	unsigned long flags;
+
+	spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+	scsi_dh_data = sdev->scsi_dh_data;
+	sdev->scsi_dh_data = NULL;
+	spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+	module_put(THIS_MODULE);
+
+	sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", HP_SW_NAME);
+
+	kfree(scsi_dh_data);
+}
+
+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 Active/Passive driver");
+MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu");
+MODULE_LICENSE("GPL");