[dm-devel] [PATCH 5/9] scsi_dh: add EMC Clariion device handler
Chandra Seetharaman
sekharan at us.ibm.com
Thu Jan 24 00:31:31 UTC 2008
Subject: scsi_dh: add EMC Clariion device handler
From: Mike Christie <michaelc at cs.wisc.edu>
This adds support for EMC Clariions. It is just a port of what is in
mainline. Ed's patches will be intergrated in a different patch which adds
more advanced functionality.
Signed-off-by: Mike Christie <michaelc at cs.wisc.edu>
Signed-off-by: Chandra Seetharaman <sekharan at us.ibm.com>
---
drivers/scsi/device_handler/Kconfig | 6 6 + 0 - 0 !
drivers/scsi/device_handler/Makefile | 2 2 + 0 - 0 !
drivers/scsi/device_handler/scsi_dh_emc.c | 360 360 + 0 - 0 !
3 files changed, 368 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
@@ -13,4 +13,10 @@ menuconfig SCSI_DH
if SCSI_DH
+config SCSI_DH_EMC
+ tristate "EMC CLARiiON Device Handler"
+ help
+ If you have a EMC CLARiiON 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
@@ -1,3 +1,5 @@
#
# SCSI Device Handler
#
+
+obj-$(CONFIG_SCSI_DH_EMC) += scsi_dh_emc.o
Index: linux-2.6.24-rc8/drivers/scsi/device_handler/scsi_dh_emc.c
===================================================================
--- /dev/null
+++ linux-2.6.24-rc8/drivers/scsi/device_handler/scsi_dh_emc.c
@@ -0,0 +1,360 @@
+/*
+ * Target driver for EMC CLARiiON AX/CX-series hardware.
+ * Based on code from Lars Marowsky-Bree <lmb at suse.de>
+ * and Ed Goggin <egoggin at emc.com>.
+ *
+ * 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_eh.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_driver.h>
+
+#define CLARIION_NAME "emc_clariion"
+
+#define CLARIION_TRESPASS_PAGE 0x22
+#define CLARIION_BUFFER_SIZE 0x80
+#define CLARIION_TIMEOUT (60 * HZ)
+#define CLARIION_UNBOUND_LU -1
+#define CLARIION_RETRIES 3
+
+struct clariion_dh_data {
+ /*
+ * Use short trespass command (FC-series) or the long version
+ * (default for AX/CX CLARiiON arrays).
+ */
+ unsigned short_trespass;
+ /*
+ * Whether or not (default) to honor SCSI reservations when
+ * initiating a switch-over.
+ */
+ unsigned hr;
+ /* I/O buffer for both MODE_SELECT and INQUIRY commands. */
+ char buffer[CLARIION_BUFFER_SIZE];
+ /*
+ * SCSI sense buffer for commands -- assumes serial issuance
+ * and completion sequence of all commands for same multipath.
+ */
+ unsigned char sense[SCSI_SENSE_BUFFERSIZE];
+};
+
+static unsigned char long_trespass[] = {
+ 0, 0, 0, 0,
+ CLARIION_TRESPASS_PAGE, /* Page code */
+ 0x09, /* Page length - 2 */
+ 0x81, /* Trespass code + Honor reservation bit */
+ 0xff, 0xff, /* Trespass target */
+ 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
+};
+
+static unsigned char long_trespass_hr[] = {
+ 0, 0, 0, 0,
+ CLARIION_TRESPASS_PAGE, /* Page code */
+ 0x09, /* Page length - 2 */
+ 0x01, /* Trespass code + Honor reservation bit */
+ 0xff, 0xff, /* Trespass target */
+ 0, 0, 0, 0, 0, 0 /* Reserved bytes / unknown */
+};
+
+static unsigned char short_trespass[] = {
+ 0, 0, 0, 0,
+ CLARIION_TRESPASS_PAGE, /* Page code */
+ 0x02, /* Page length - 2 */
+ 0x81, /* Trespass code + Honor reservation bit */
+ 0xff, /* Trespass target */
+};
+
+static unsigned char short_trespass_hr[] = {
+ 0, 0, 0, 0,
+ CLARIION_TRESPASS_PAGE, /* Page code */
+ 0x02, /* Page length - 2 */
+ 0x01, /* Trespass code + Honor reservation bit */
+ 0xff, /* Trespass target */
+};
+
+/*
+ * Parse MODE_SELECT cmd reply.
+ */
+static int parse_trespass_rsp(struct scsi_device *sdev, char *sense,
+ int result)
+{
+ struct scsi_sense_hdr sshdr;
+ int err = 0;
+
+ if (status_byte(result) == CHECK_CONDITION &&
+ scsi_normalize_sense(sense, SCSI_SENSE_BUFFERSIZE, &sshdr)) {
+ sdev_printk(KERN_ERR, sdev, "Found valid sense data 0x%2x, "
+ "0x%2x, 0x%2x while sending CLARiiON trespass "
+ "command.\n", sshdr.sense_key, sshdr.asc,
+ sshdr.ascq);
+
+ if ((sshdr.sense_key == 0x05) && (sshdr.asc == 0x04) &&
+ (sshdr.ascq == 0x00)) {
+ /*
+ * Array based copy in progress -- do not send
+ * pg_init or copy will be aborted mid-stream.
+ */
+ sdev_printk(KERN_INFO, sdev, "Array Based Copy in "
+ "progress while sending CLARiiON trespass "
+ "command.\n");
+ err = BLKERR_DEV_TEMP_BUSY;
+ } else if ((sshdr.sense_key == 0x02) && (sshdr.asc == 0x04) &&
+ (sshdr.ascq == 0x03)) {
+ /*
+ * LUN Not Ready - Manual Intervention Required
+ * indicates in-progress ucode upgrade (NDU).
+ */
+ sdev_printk(KERN_INFO, sdev, "Detected in-progress "
+ "ucode upgrade NDU operation while sending "
+ "CLARiiON trespass command.\n");
+ err = BLKERR_DEV_TEMP_BUSY;
+ } else
+ err = BLKERR_DEV_FAILED;
+ } else if (result) {
+ sdev_printk(KERN_ERR, sdev, "Error 0x%x while sending "
+ "CLARiiON trespass command.\n", result);
+ err = BLKERR_IO;
+ }
+
+ return err;
+}
+
+static void trespass_done(struct request *req, int uptodate)
+{
+ struct request *act_req = req->end_io_data;
+ struct scsi_device *sdev = req->q->queuedata;
+ int err_flags, result = req->errors;
+ char *sense = req->sense;
+
+ sdev_printk(KERN_NOTICE, sdev, "Trespass compeleted. Uptodate %d error "
+ "%d.\n", uptodate, req->errors);
+
+ __blk_put_request(req->q, req);
+
+ err_flags = parse_trespass_rsp(sdev, sense, result);
+ if (err_flags) {
+ scsi_blk_linux_cmd_done(act_req, err_flags);
+ return;
+ }
+
+ scsi_blk_linux_cmd_done(act_req, BLKERR_OK);
+}
+
+static int execute_trespass(struct request *act_req)
+{
+ struct scsi_device *sdev = act_req->q->queuedata;
+ struct clariion_dh_data *csdev = sdev->sdev_dh_data;
+ struct request *req;
+ unsigned char *page22;
+ unsigned size;
+
+ if (csdev->short_trespass) {
+ page22 = csdev->hr ? short_trespass_hr : short_trespass;
+ size = sizeof(short_trespass);
+ } else {
+ page22 = csdev->hr ? long_trespass_hr : long_trespass;
+ size = sizeof(long_trespass);
+ }
+
+ req = blk_get_request(sdev->request_queue, 1, GFP_ATOMIC);
+ if (!req)
+ return BLKERR_RES_TEMP_UNAVAIL;
+
+ req->cmd_type = REQ_TYPE_BLOCK_PC;
+ req->cmd_flags |= REQ_FAILFAST;
+ req->timeout = CLARIION_TIMEOUT;
+ req->retries = CLARIION_RETRIES;
+ req->end_io_data = act_req;
+ req->sense = csdev->sense;
+ memset(req->sense, 0, SCSI_SENSE_BUFFERSIZE);
+ req->sense_len = 0;
+
+ memset(req->cmd, 0, MAX_COMMAND_SIZE);
+ req->cmd[0] = MODE_SELECT;
+ req->cmd[1] = 0x10;
+ req->cmd[4] = size;
+ req->cmd_len = COMMAND_SIZE(MODE_SELECT);
+ memcpy(csdev->buffer, page22, size);
+
+ if (blk_rq_map_kern(sdev->request_queue, req, csdev->buffer,
+ size, GFP_ATOMIC)) {
+ __blk_put_request(req->q, req);
+ return BLKERR_RES_TEMP_UNAVAIL;
+ }
+
+ sdev_printk(KERN_NOTICE, sdev, "Failing over device\n.");
+ blk_execute_rq_nowait(req->q, NULL, req, 1, trespass_done);
+ return BLKERR_OK;
+}
+
+static void clariion_transition(struct request *req)
+{
+ int err;
+
+ err = execute_trespass(req);
+ if (err)
+ scsi_blk_linux_cmd_done(req, err);
+}
+
+static int clariion_check_sense(struct scsi_device *sdev,
+ struct scsi_sense_hdr *sense_hdr)
+{
+ switch (sense_hdr->sense_key) {
+ case NOT_READY:
+ if (sense_hdr->asc == 0x04 && sense_hdr->ascq == 0x03)
+ /*
+ * LUN Not Ready - Manual Intervention Required
+ * indicates this is a passive path.
+ *
+ * FIXME: However, if this is seen and EVPD C0
+ * indicates that this is due to a NDU in
+ * progress, we should set FAIL_PATH too.
+ * This indicates we might have to do a SCSI
+ * inquiry in the end_io path. Ugh.
+ *
+ * Can return FAILED only when we want the error
+ * recovery process to kick in.
+ */
+ return SUCCESS;
+ break;
+ case ILLEGAL_REQUEST:
+ if (sense_hdr->asc == 0x25 && sense_hdr->ascq == 0x01)
+ /*
+ * An array based copy is in progress. Do not
+ * fail the path, do not bypass to another PG,
+ * do not retry. Fail the IO immediately.
+ * (Actually this is the same conclusion as in
+ * the default handler, but lets make sure.)
+ *
+ * Can return FAILED only when we want the error
+ * recovery process to kick in.
+ */
+ return SUCCESS;
+ break;
+ case UNIT_ATTENTION:
+ if (sense_hdr->asc == 0x29 && sense_hdr->ascq == 0x00)
+ /*
+ * Unit Attention Code. This is the first IO
+ * to the new path, so just retry.
+ */
+ return NEEDS_RETRY;
+ break;
+ }
+
+ /* success just means we do not care what scsi-ml does */
+ return SUCCESS;
+}
+
+static const struct {
+ char *vendor;
+ char *model;
+} clariion_dev_list[] = {
+ {"DGC", "RAID"},
+ {"DGC", "DISK"},
+ {NULL, NULL},
+};
+
+static int clariion_bus_notify(struct notifier_block *, unsigned long, void *);
+
+static struct scsi_device_handler clariion_dh = {
+ .name = CLARIION_NAME,
+ .module = THIS_MODULE,
+ .nb.notifier_call = clariion_bus_notify,
+ .check_sense = clariion_check_sense,
+ .transition = clariion_transition,
+};
+
+/*
+ * TODO: need some interface so we can set trespass values
+ */
+static int clariion_bus_notify(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct device *dev = data;
+ struct scsi_device *sdev = to_scsi_device(dev);
+ struct clariion_dh_data *dh_data;
+ int i, found = 0;
+ unsigned long flags;
+
+ if (action == BUS_NOTIFY_ADD_DEVICE) {
+ for (i = 0; clariion_dev_list[i].vendor; i++) {
+ if (!strncmp(sdev->vendor, clariion_dev_list[i].vendor,
+ strlen(clariion_dev_list[i].vendor)) &&
+ !strncmp(sdev->model, clariion_dev_list[i].model,
+ strlen(clariion_dev_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",
+ CLARIION_NAME);
+ goto out;
+ }
+
+ spin_lock_irqsave(sdev->request_queue->queue_lock, flags);
+ sdev->sdev_dh_data = dh_data;
+ sdev->sdev_dh = &clariion_dh;
+ spin_unlock_irqrestore(sdev->request_queue->queue_lock, flags);
+
+ sdev_printk(KERN_NOTICE, sdev, "Attached %s.\n",
+ CLARIION_NAME);
+
+ } else if (action == BUS_NOTIFY_DEL_DEVICE) {
+ if (sdev->sdev_dh != &clariion_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",
+ CLARIION_NAME);
+
+ kfree(dh_data);
+ }
+
+out:
+ return 0;
+}
+
+
+static int __init clariion_init(void)
+{
+ return scsi_register_device_handler(&clariion_dh);
+}
+
+static void __exit clariion_exit(void)
+{
+ scsi_unregister_device_handler(&clariion_dh);
+}
+
+module_init(clariion_init);
+module_exit(clariion_exit);
+
+MODULE_DESCRIPTION("EMC CX/AX/FC-family driver");
+MODULE_AUTHOR("Mike Christie <michaelc at cs.wisc.edu");
+MODULE_LICENSE("GPL");
--
----------------------------------------------------------------------
Chandra Seetharaman | Be careful what you choose....
- sekharan at us.ibm.com | .......you may get it.
----------------------------------------------------------------------
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