path: root/drivers/scsi/device_handler/scsi_dh_rdac.c

/*
 * LSI/Engenio/NetApp E-Series RDAC SCSI Device Handler
 *
 * Copyright (C) 2005 Mike Christie. All rights reserved.
 * Copyright (C) Chandra Seetharaman, IBM Corp. 2007
 *
 * 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 of the License, 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; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */
#include <scsi/scsi.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_dh.h>
#include <linux/workqueue.h>
#include <linux/slab.h>
#include <linux/module.h>

#define RDAC_NAME "rdac"
#define RDAC_RETRY_COUNT 5

/*
 * LSI mode page stuff
 *
 * These struct definitions and the forming of the
 * mode page were taken from the LSI RDAC 2.4 GPL'd
 * driver, and then converted to Linux conventions.
 */
#define RDAC_QUIESCENCE_TIME 20
/*
 * Page Codes
 */
#define RDAC_PAGE_CODE_REDUNDANT_CONTROLLER 0x2c

/*
 * Controller modes definitions
 */
#define RDAC_MODE_TRANSFER_SPECIFIED_LUNS	0x02

/*
 * RDAC Options field
 */
#define RDAC_FORCED_QUIESENCE 0x02

#define RDAC_TIMEOUT	(60 * HZ)
#define RDAC_RETRIES	3

struct rdac_mode_6_hdr {
	u8	data_len;
	u8	medium_type;
	u8	device_params;
	u8	block_desc_len;
};

struct rdac_mode_10_hdr {
	u16	data_len;
	u8	medium_type;
	u8	device_params;
	u16	reserved;
	u16	block_desc_len;
};

struct rdac_mode_common {
	u8	controller_serial[16];
	u8	alt_controller_serial[16];
	u8	rdac_mode[2];
	u8	alt_rdac_mode[2];
	u8	quiescence_timeout;
	u8	rdac_options;
};

struct rdac_pg_legacy {
	struct rdac_mode_6_hdr hdr;
	u8	page_code;
	u8	page_len;
	struct rdac_mode_common common;
#define MODE6_MAX_LUN	32
	u8	lun_table[MODE6_MAX_LUN];
	u8	reserved2[32];
	u8	reserved3;
	u8	reserved4;
};

struct rdac_pg_expanded {
	struct rdac_mode_10_hdr hdr;
	u8	page_code;
	u8	subpage_code;
	u8	page_len[2];
	struct rdac_mode_common common;
	u8	lun_table[256];
	u8	reserved3;
	u8	reserved4;
};

struct c9_inquiry {
	u8	peripheral_info;
	u8	page_code;	/* 0xC9 */
	u8	reserved1;
	u8	page_len;
	u8	page_id[4];	/* "vace" */
	u8	avte_cvp;
	u8	path_prio;
	u8	reserved2[38];
};

#define SUBSYS_ID_LEN	16
#define SLOT_ID_LEN	2
#define ARRAY_LABEL_LEN	31

struct c4_inquiry {
	u8	peripheral_info;
	u8	page_code;	/* 0xC4 */
	u8	reserved1;
	u8	page_len;
	u8	page_id[4];	/* "subs" */
	u8	subsys_id[SUBSYS_ID_LEN];
	u8	revision[4];
	u8	slot_id[SLOT_ID_LEN];
	u8	reserved[2];
};

#define UNIQUE_ID_LEN 16
struct c8_inquiry {
	u8	peripheral_info;
	u8	page_code; /* 0xC8 */
	u8	reserved1;
	u8	page_len;
	u8	page_id[4]; /* "edid" */
	u8	reserved2[3];
	u8	vol_uniq_id_len;
	u8	vol_uniq_id[16];
	u8	vol_user_label_len;
	u8	vol_user_label[60];
	u8	array_uniq_id_len;
	u8	array_unique_id[UNIQUE_ID_LEN];
	u8	array_user_label_len;
	u8	array_user_label[60];
	u8	lun[8];
};

struct rdac_controller {
	u8			array_id[UNIQUE_ID_LEN];
	int			use_ms10;
	struct kref		kref;
	struct list_head	node; /* list of all controllers */
	union			{
		struct rdac_pg_legacy legacy;
		struct rdac_pg_expanded expanded;
	} mode_select;
	u8	index;
	u8	array_name[ARRAY_LABEL_LEN];
	struct Scsi_Host	*host;
	spinlock_t		ms_lock;
	int			ms_queued;
	struct work_struct	ms_work;
	struct scsi_device	*ms_sdev;
	struct list_head	ms_head;
};

struct c2_inquiry {
	u8	peripheral_info;
	u8	page_code;	/* 0xC2 */
	u8	reserved1;
	u8	page_len;
	u8	page_id[4];	/* "swr4" */
	u8	sw_version[3];
	u8	sw_date[3];
	u8	features_enabled;
	u8	max_lun_supported;
	u8	partitions[239]; /* Total allocation length should be 0xFF */
};

struct rdac_dh_data {
	struct rdac_controller	*ctlr;
#define UNINITIALIZED_LUN	(1 << 8)
	unsigned		lun;

#define RDAC_MODE		0
#define RDAC_MODE_AVT		1
#define RDAC_MODE_IOSHIP	2
	unsigned char		mode;

#define RDAC_STATE_ACTIVE	0
#define RDAC_STATE_PASSIVE	1
	unsigned char		state;

#define RDAC_LUN_UNOWNED	0
#define RDAC_LUN_OWNED		1
	char			lun_state;

#define RDAC_PREFERRED		0
#define RDAC_NON_PREFERRED	1
	char			preferred;

	unsigned char		sense[SCSI_SENSE_BUFFERSIZE];
	union			{
		struct c2_inquiry c2;
		struct c4_inquiry c4;
		struct c8_inquiry c8;
		struct c9_inquiry c9;
	} inq;
};

static const char *mode[] = {
	"RDAC",
	"AVT",
	"IOSHIP",
};
static const char *lun_state[] =
{
	"unowned",