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Commit 5e7dccad authored by Chandra Seetharaman's avatar Chandra Seetharaman Committed by James Bottomley
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[SCSI] scsi_dh: add EMC Clariion device handler 



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: default avatarChandra Seetharaman <sekharan@us.ibm.com>
Signed-off-by: default avatarMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: default avatarJames Bottomley <James.Bottomley@HansenPartnership.com>
parent f6dd337e

drivers/scsi/device_handler/Kconfig

+6 −0
Original line number Diff line number Diff line
@@ -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.

drivers/scsi/device_handler/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -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

drivers/scsi/device_handler/scsi_dh_emc.c

0 → 100644
+499 −0
Original line number Diff line number Diff line 
/*

 * Target driver for EMC CLARiiON AX/CX-series hardware.

 * Based on code from Lars Marowsky-Bree <lmb@suse.de>

 * and Ed Goggin <egoggin@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,

					     &current_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) {

		if (sdev->scsi_dh_data == NULL ||

				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@cs.wisc.edu>, Chandra Seetharaman <sekharan@us.ibm.com>");

MODULE_LICENSE("GPL");