[dm-devel] [PATCH 4/7] scsi_dh: add EMC Clariion device handler
Chandra Seetharaman
sekharan at us.ibm.com
Wed Apr 16 01:18:42 UTC 2008
Subject: scsi_dh: add EMC Clariion device handler
From: Chandra Seetharaman <sekharan at us.ibm.com>
This adds support for EMC Clariions. This patch has the features that
currently exists in mainline and advanced features from Ed's patches.
Signed-off-by: Chandra Seetharaman <sekharan at us.ibm.com>
Signed-off-by: Mike Christie <michaelc at cs.wisc.edu>
---
drivers/scsi/device_handler/Kconfig | 6 6 + 0 - 0 !
drivers/scsi/device_handler/Makefile | 1 1 + 0 - 0 !
drivers/scsi/device_handler/scsi_dh_emc.c | 499 499 + 0 - 0 !
3 files changed, 506 insertions(+)
Index: linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/Kconfig
===================================================================
--- linux-2.6.25-rc8-mm2.orig/drivers/scsi/device_handler/Kconfig
+++ linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/Kconfig
@@ -24,3 +24,9 @@ config SCSI_DH_HP_SW
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.
+
+config SCSI_DH_EMC
+ tristate "EMC CLARiiON Device Handler"
+ depends on SCSI_DH
+ help
+ If you have a EMC CLARiiON select y. Otherwise, say N.
Index: linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/scsi_dh_emc.c
===================================================================
--- /dev/null
+++ linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/scsi_dh_emc.c
@@ -0,0 +1,499 @@
+/*
+ * 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 <scsi/scsi.h>
+#include <scsi/scsi_eh.h>
+#include <scsi/scsi_dh.h>
+#include <scsi/scsi_device.h>
+
+#define CLARIION_NAME "emc_clariion"
+
+#define CLARIION_TRESPASS_PAGE 0x22
+#define CLARIION_BUFFER_SIZE 0x80
+#define CLARIION_TIMEOUT (60 * HZ)
+#define CLARIION_RETRIES 3
+#define CLARIION_UNBOUND_LU -1
+
+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 */
+};
+
+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];
+ /* which SP (A=0,B=1,UNBOUND=-1) is dflt SP for path's mapped dev */
+ int default_sp;
+ /* which SP (A=0,B=1,UNBOUND=-1) is active for path's mapped dev */
+ int current_sp;
+};
+
+static inline struct clariion_dh_data
+ *get_clariion_data(struct scsi_device *sdev)
+{
+ struct scsi_dh_data *scsi_dh_data = sdev->scsi_dh_data;
+ BUG_ON(scsi_dh_data == NULL);
+ return ((struct clariion_dh_data *) scsi_dh_data->buf);
+}
+
+/*
+ * Parse MODE_SELECT cmd reply.
+ */
+static int trespass_endio(struct scsi_device *sdev, int result)
+{
+ int err = SCSI_DH_OK;
+ struct scsi_sense_hdr sshdr;
+ struct clariion_dh_data *csdev = get_clariion_data(sdev);
+ char *sense = csdev->sense;
+
+ 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
+ * mode_select or copy will be aborted mid-stream.
+ */
+ sdev_printk(KERN_INFO, sdev, "Array Based Copy in "
+ "progress while sending CLARiiON trespass "
+ "command.\n");
+ err = SCSI_DH_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 = SCSI_DH_DEV_TEMP_BUSY;
+ } else
+ err = SCSI_DH_DEV_FAILED;
+ } else if (result) {
+ sdev_printk(KERN_ERR, sdev, "Error 0x%x while sending "
+ "CLARiiON trespass command.\n", result);
+ err = SCSI_DH_IO;
+ }
+
+ return err;
+}
+
+static int parse_sp_info_reply(struct scsi_device *sdev, int result,
+ int *default_sp, int *current_sp, int *new_current_sp)
+{
+ int err = SCSI_DH_OK;
+ struct clariion_dh_data *csdev = get_clariion_data(sdev);
+
+ if (result == 0) {
+ /* check for in-progress ucode upgrade (NDU) */
+ if (csdev->buffer[48] != 0) {
+ sdev_printk(KERN_NOTICE, sdev, "Detected in-progress "
+ "ucode upgrade NDU operation while finding "
+ "current active SP.");
+ err = SCSI_DH_DEV_TEMP_BUSY;
+ } else {
+ *default_sp = csdev->buffer[5];
+
+ if (csdev->buffer[4] == 2)
+ /* SP for path is current */
+ *current_sp = csdev->buffer[8];
+ else {
+ if (csdev->buffer[4] == 1)
+ /* SP for this path is NOT current */
+ if (csdev->buffer[8] == 0)
+ *current_sp = 1;
+ else
+ *current_sp = 0;
+ else
+ /* unbound LU or LUNZ */
+ *current_sp = CLARIION_UNBOUND_LU;
+ }
+ *new_current_sp = csdev->buffer[8];
+ }
+ } else {
+ struct scsi_sense_hdr sshdr;
+
+ err = SCSI_DH_IO;
+
+ if (scsi_normalize_sense(csdev->sense, SCSI_SENSE_BUFFERSIZE,
+ &sshdr))
+ sdev_printk(KERN_ERR, sdev, "Found valid sense data "
+ "0x%2x, 0x%2x, 0x%2x while finding current "
+ "active SP.", sshdr.sense_key, sshdr.asc,
+ sshdr.ascq);
+ else
+ sdev_printk(KERN_ERR, sdev, "Error 0x%x finding "
+ "current active SP.", result);
+ }
+
+ return err;
+}
+
+static int sp_info_endio(struct scsi_device *sdev, int result,
+ int mode_select_sent, int *done)
+{
+ struct clariion_dh_data *csdev = get_clariion_data(sdev);
+ int err_flags, default_sp, current_sp, new_current_sp;
+
+ err_flags = parse_sp_info_reply(sdev, result, &default_sp,
+ ¤t_sp, &new_current_sp);
+
+ if (err_flags != SCSI_DH_OK)
+ goto done;
+
+ if (mode_select_sent) {
+ csdev->default_sp = default_sp;
+ csdev->current_sp = current_sp;
+ } else {
+ /*
+ * Issue the actual module_selec request IFF either
+ * (1) we do not know the identity of the current SP OR
+ * (2) what we think we know is actually correct.
+ */
+ if ((current_sp != CLARIION_UNBOUND_LU) &&
+ (new_current_sp != current_sp)) {
+
+ csdev->default_sp = default_sp;
+ csdev->current_sp = current_sp;
+
+ sdev_printk(KERN_INFO, sdev, "Ignoring path group "
+ "switch-over command for CLARiiON SP%s since "
+ " mapped device is already initialized.",
+ current_sp ? "B" : "A");
+ if (done)
+ *done = 1; /* as good as doing it */
+ }
+ }
+done:
+ return err_flags;
+}
+
+/*
+* Get block request for REQ_BLOCK_PC command issued to path. Currently
+* limited to MODE_SELECT (trespass) and INQUIRY (VPD page 0xC0) commands.
+*
+* Uses data and sense buffers in hardware handler context structure and
+* assumes serial servicing of commands, both issuance and completion.
+*/
+static struct request *get_req(struct scsi_device *sdev, int cmd)
+{
+ struct clariion_dh_data *csdev = get_clariion_data(sdev);
+ struct request *rq;
+ unsigned char *page22;
+ int len = 0;
+
+ rq = blk_get_request(sdev->request_queue,
+ (cmd == MODE_SELECT) ? WRITE : READ, GFP_ATOMIC);
+ if (!rq) {
+ sdev_printk(KERN_INFO, sdev, "get_req: blk_get_request failed");
+ return NULL;
+ }
+
+ memset(&rq->cmd, 0, BLK_MAX_CDB);
+ rq->cmd[0] = cmd;
+ rq->cmd_len = COMMAND_SIZE(rq->cmd[0]);
+
+ switch (cmd) {
+ case MODE_SELECT:
+ if (csdev->short_trespass) {
+ page22 = csdev->hr ? short_trespass_hr : short_trespass;
+ len = sizeof(short_trespass);
+ } else {
+ page22 = csdev->hr ? long_trespass_hr : long_trespass;
+ len = sizeof(long_trespass);
+ }
+ /*
+ * Can't DMA from kernel BSS -- must copy selected trespass
+ * command mode page contents to context buffer which is
+ * allocated by kmalloc.
+ */
+ BUG_ON((len > CLARIION_BUFFER_SIZE));
+ memcpy(csdev->buffer, page22, len);
+ rq->cmd_flags |= REQ_RW;
+ rq->cmd[1] = 0x10;
+ break;
+ case INQUIRY:
+ rq->cmd[1] = 0x1;
+ rq->cmd[2] = 0xC0;
+ len = CLARIION_BUFFER_SIZE;
+ memset(csdev->buffer, 0, CLARIION_BUFFER_SIZE);
+ break;
+ default:
+ BUG_ON(1);
+ break;
+ }
+
+ rq->cmd[4] = len;
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
+ rq->cmd_flags |= REQ_FAILFAST;
+ rq->timeout = CLARIION_TIMEOUT;
+ rq->retries = CLARIION_RETRIES;
+
+ rq->sense = csdev->sense;
+ memset(rq->sense, 0, SCSI_SENSE_BUFFERSIZE);
+ rq->sense_len = 0;
+
+ if (blk_rq_map_kern(sdev->request_queue, rq, csdev->buffer,
+ len, GFP_ATOMIC)) {
+ __blk_put_request(rq->q, rq);
+ return NULL;
+ }
+
+ return rq;
+}
+
+static int send_cmd(struct scsi_device *sdev, int cmd)
+{
+ struct request *rq = get_req(sdev, cmd);
+
+ if (!rq)
+ return SCSI_DH_RES_TEMP_UNAVAIL;
+
+ return blk_execute_rq(sdev->request_queue, NULL, rq, 1);
+}
+
+static int clariion_activate(struct scsi_device *sdev)
+{
+ int result, done = 0;
+
+ result = send_cmd(sdev, INQUIRY);
+ result = sp_info_endio(sdev, result, 0, &done);
+ if (result || done)
+ goto done;
+
+ result = send_cmd(sdev, MODE_SELECT);
+ result = trespass_endio(sdev, result);
+ if (result)
+ goto done;
+
+ result = send_cmd(sdev, INQUIRY);
+ result = sp_info_endio(sdev, result, 1, NULL);
+done:
+ return result;
+}
+
+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,
+ .activate = clariion_activate,
+};
+
+/*
+ * 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 scsi_dh_data *scsi_dh_data;
+ struct clariion_dh_data *h;
+ 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;
+
+ scsi_dh_data = kzalloc(sizeof(struct scsi_device_handler *)
+ + sizeof(*h) , GFP_KERNEL);
+ if (!scsi_dh_data) {
+ sdev_printk(KERN_ERR, sdev, "Attach failed %s.\n",
+ CLARIION_NAME);
+ goto out;
+ }
+
+ scsi_dh_data->scsi_dh = &clariion_dh;
+ h = (struct clariion_dh_data *) scsi_dh_data->buf;
+ h->default_sp = CLARIION_UNBOUND_LU;
+ h->current_sp = CLARIION_UNBOUND_LU;
+
+ 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_NOTICE, sdev, "Attached %s.\n", CLARIION_NAME);
+ try_module_get(THIS_MODULE);
+
+ } else if (action == BUS_NOTIFY_DEL_DEVICE) {
+ BUG_ON(sdev->scsi_dh_data == NULL);
+ if (sdev->scsi_dh_data->scsi_dh != &clariion_dh)
+ goto out;
+
+ 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);
+
+ sdev_printk(KERN_NOTICE, sdev, "Dettached %s.\n",
+ CLARIION_NAME);
+
+ kfree(scsi_dh_data);
+ module_put(THIS_MODULE);
+ }
+
+out:
+ return 0;
+}
+
+static int __init clariion_init(void)
+{
+ int r;
+
+ r = scsi_register_device_handler(&clariion_dh);
+ if (r != 0)
+ printk(KERN_ERR "Failed to register scsi device handler.");
+ return r;
+}
+
+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>, Chandra Seetharaman <sekharan at us.ibm.com>");
+MODULE_LICENSE("GPL");
Index: linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/Makefile
===================================================================
--- linux-2.6.25-rc8-mm2.orig/drivers/scsi/device_handler/Makefile
+++ linux-2.6.25-rc8-mm2/drivers/scsi/device_handler/Makefile
@@ -4,3 +4,4 @@
obj-$(CONFIG_SCSI_DH) += scsi_dh.o
obj-$(CONFIG_SCSI_DH_RDAC) += scsi_dh_rdac.o
obj-$(CONFIG_SCSI_DH_HP_SW) += scsi_dh_hp_sw.o
+obj-$(CONFIG_SCSI_DH_EMC) += scsi_dh_emc.o
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