path: root/drivers/s390/scsi/zfcp_def.h

/*
 * zfcp device driver
 *
 * Global definitions for the zfcp device driver.
 *
 * Copyright IBM Corporation 2002, 2008
 */

#ifndef ZFCP_DEF_H
#define ZFCP_DEF_H

/*************************** INCLUDES *****************************************/

#include <linux/init.h>
#include <linux/moduleparam.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/slab.h>
#include <linux/mempool.h>
#include <linux/syscalls.h>
#include <linux/scatterlist.h>
#include <linux/ioctl.h>
#include <scsi/scsi.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_fc.h>
#include <asm/ccwdev.h>
#include <asm/qdio.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include "zfcp_dbf.h"
#include "zfcp_fsf.h"


/********************* GENERAL DEFINES *********************************/

/**
 * zfcp_sg_to_address - determine kernel address from struct scatterlist
 * @list: struct scatterlist
 * Return: kernel address
 */
static inline void *
zfcp_sg_to_address(struct scatterlist *list)
{
	return sg_virt(list);
}

/**
 * zfcp_address_to_sg - set up struct scatterlist from kernel address
 * @address: kernel address
 * @list: struct scatterlist
 * @size: buffer size
 */
static inline void
zfcp_address_to_sg(void *address, struct scatterlist *list, unsigned int size)
{
	sg_set_buf(list, address, size);
}

#define REQUEST_LIST_SIZE 128

/********************* SCSI SPECIFIC DEFINES *********************************/
#define ZFCP_SCSI_ER_TIMEOUT                    (10*HZ)

/********************* CIO/QDIO SPECIFIC DEFINES *****************************/

/* Adapter Identification Parameters */
#define ZFCP_CONTROL_UNIT_TYPE  0x1731
#define ZFCP_CONTROL_UNIT_MODEL 0x03
#define ZFCP_DEVICE_TYPE        0x1732
#define ZFCP_DEVICE_MODEL       0x03
#define ZFCP_DEVICE_MODEL_PRIV	0x04

/* allow as many chained SBALs as are supported by hardware */
#define ZFCP_MAX_SBALS_PER_REQ		FSF_MAX_SBALS_PER_REQ
#define ZFCP_MAX_SBALS_PER_CT_REQ	FSF_MAX_SBALS_PER_REQ
#define ZFCP_MAX_SBALS_PER_ELS_REQ	FSF_MAX_SBALS_PER_ELS_REQ

/* DMQ bug workaround: don't use last SBALE */
#define ZFCP_MAX_SBALES_PER_SBAL	(QDIO_MAX_ELEMENTS_PER_BUFFER - 1)

/* index of last SBALE (with respect to DMQ bug workaround) */
#define ZFCP_LAST_SBALE_PER_SBAL	(ZFCP_MAX_SBALES_PER_SBAL - 1)

/* max. number of (data buffer) SBALEs in largest SBAL chain */
#define ZFCP_MAX_SBALES_PER_REQ		\
	(ZFCP_MAX_SBALS_PER_REQ * ZFCP_MAX_SBALES_PER_SBAL - 2)
        /* request ID + QTCB in SBALE 0 + 1 of first SBAL in chain */

#define ZFCP_MAX_SECTORS (ZFCP_MAX_SBALES_PER_REQ * 8)
        /* max. number of (data buffer) SBALEs in largest SBAL chain
           multiplied with number of sectors per 4k block */

#define ZFCP_SBAL_TIMEOUT               (5*HZ)

#define ZFCP_TYPE2_RECOVERY_TIME        8	/* seconds */

#define QBUFF_PER_PAGE			(PAGE_SIZE / sizeof(struct qdio_buffer))

/********************* FSF SPECIFIC DEFINES *********************************/

#define ZFCP_ULP_INFO_VERSION                   26
#define ZFCP_QTCB_VERSION	FSF_QTCB_CURRENT_VERSION
/* ATTENTION: value must not be used by hardware */
#define FSF_QTCB_UNSOLICITED_STATUS		0x6305
#define ZFCP_STATUS_READS_RECOM		        FSF_STATUS_READS_RECOM

/* Do 1st retry in 1 second, then double the timeout for each following retry */
#define ZFCP_EXCHANGE_CONFIG_DATA_FIRST_SLEEP	1
#define ZFCP_EXCHANGE_CONFIG_DATA_RETRIES	7

/* timeout value for "default timer" for fsf requests */
#define ZFCP_FSF_REQUEST_TIMEOUT (60*HZ)

/*************** FIBRE CHANNEL PROTOCOL SPECIFIC DEFINES ********************/

typedef unsigned long long wwn_t;
typedef unsigned long long fcp_lun_t;
/* data length field may be at variable position in FCP-2 FCP_CMND IU */
typedef unsigned int       fcp_dl_t;

#define ZFCP_FC_SERVICE_CLASS_DEFAULT	FSF_CLASS_3

/* timeout for name-server lookup (in seconds) */
#define ZFCP_NS_GID_PN_TIMEOUT		10

/* largest SCSI command we can process */
/* FCP-2 (FCP_CMND IU) allows up to (255-3+16) */
#define ZFCP_MAX_SCSI_CMND_LENGTH	255
/* maximum number of commands in LUN queue (tagged queueing) */
#define ZFCP_CMND_PER_LUN               32

/* task attribute values in FCP-2 FCP_CMND IU */
#define SIMPLE_Q	0
#define HEAD_OF_Q	1
#define ORDERED_Q	2
#define ACA_Q		4
#define UNTAGGED	5

/* task management flags in FCP-2 FCP_CMND IU */
#define FCP_CLEAR_ACA		0x40
#define FCP_TARGET_RESET	0x20
#define FCP_LOGICAL_UNIT_RESET	0x10
#define FCP_CLEAR_TASK_SET	0x04
#define FCP_ABORT_TASK_SET	0x02

#define FCP_CDB_LENGTH		16

#define ZFCP_DID_MASK           0x00FFFFFF

/* FCP(-2) FCP_CMND IU */
struct fcp_cmnd_iu {
	fcp_lun_t fcp_lun;	   /* FCP logical unit number */
	u8  crn;	           /* command reference number */
	u8  reserved0:5;	   /* reserved */
	u8  task_attribute:3;	   /* task attribute */
	u8  task_management_flags; /* task management flags */
	u8  add_fcp_cdb_length:6;  /* additional FCP_CDB length */
	u8  rddata:1;              /* read data */
	u8  wddata:1;              /* write data */
	u8  fcp_cdb[FCP_CDB_LENGTH];
} __attribute__((packed));

/* FCP(-2) FCP_RSP IU */
struct fcp_rsp_iu {
	u8  reserved0[10];
	union {
		struct {
			u8 reserved1:3;
			u8 fcp_conf_req:1;
			u8 fcp_resid_under:1;
			u8 fcp_resid_over:1;
			u8 fcp_sns_len_valid:1;
			u8 fcp_rsp_len_valid:1;
		} bits;
		u8 value;
	} validity;
	u8  scsi_status;
	u32 fcp_resid;
	u32 fcp_sns_len;
	u32 fcp_rsp_len;
} __attribute__((packed));


#define RSP_CODE_GOOD		 0
#define RSP_CODE_LENGTH_MISMATCH 1
#define RSP_CODE_FIELD_INVALID	 2
#define RSP_CODE_RO_MISMATCH	 3
#define RSP_CODE_TASKMAN_UNSUPP	 4
#define RSP_CODE_TASKMAN_FAILED	 5

/* see fc-fs */
#define LS_RSCN  0x61
#define LS_LOGO  0x05
#define LS_PLOGI 0x03

struct fcp_rscn_head {
        u8  command;
        u8  page_length; /* always 0x04 */
        u16 payload_len;
} __attribute__((packed));

struct fcp_rscn_element {
        u8  reserved:2;
        u8  event_qual:4;
        u8  addr_format:2;
        u32 nport_did:24;
} __attribute__((packed));

#define ZFCP_PORT_ADDRESS   0x0
#define ZFCP_AREA_ADDRESS   0x1
#define ZFCP_DOMAIN_ADDRESS 0x2
#define ZFCP_FABRIC_ADDRESS 0x3

#define ZFCP_PORTS_RANGE_PORT   0xFFFFFF
#define ZFCP_PORTS_RANGE_AREA   0xFFFF00
#define ZFCP_PORTS_RANGE_DOMAIN 0xFF0000
#define ZFCP_PORTS_RANGE_FABRIC 0x000000

#define ZFCP_NO_PORTS_PER_AREA    0x100
#define ZFCP_NO_PORTS_PER_DOMAIN  0x10000
#define ZFCP_NO_PORTS_PER_FABRIC  0x1000000

/* see fc-ph */
struct fcp_logo {
        u32 command;
        u32 nport_did;
        wwn_t nport_wwpn;
} __attribute__((packed));

/*
 * FC-FS stuff
 */
#define R_A_TOV				10 /* seconds */
#define ZFCP_ELS_TIMEOUT		(2 * R_A_TOV)

#define ZFCP_LS_RLS			0x0f
#define ZFCP_LS_ADISC			0x52
#define ZFCP_LS_RPS			0x56
#define ZFCP_LS_RSCN			0x61
#define ZFCP_LS_RNID			0x78

struct zfcp_ls_rjt_par {
	u8 action;
 	u8 reason_code;
 	u8 reason_expl;
 	u8 vendor_unique;
} __attribute__ ((packed));

struct zfcp_ls_adisc {
	u8		code;
	u8		field[3];
	u32		hard_nport_id;
	u64		wwpn;
	u64		wwnn;
	u32		nport_id;
} __attribute__ ((packed));

struct zfcp_ls_adisc_acc {
	u8		code;
	u8		field[3];
	u32		hard_nport_id;
	u64		wwpn;
	u64		wwnn;
	u32		nport_id;
} __attribute__ ((packed));

struct zfcp_rc_entry {
	u8 code;
	const char *description;
};

/*
 * FC-GS-2 stuff
 */
#define ZFCP_CT_REVISION		0x01
#define ZFCP_CT_DIRECTORY_SERVICE	0xFC
#define ZFCP_CT_NAME_SERVER		0x02
#define ZFCP_CT_SYNCHRONOUS		0x00
#define ZFCP_CT_SCSI_FCP		0x08
#define ZFCP_CT_UNABLE_TO_PERFORM_CMD	0x09
#define ZFCP_CT_GID_PN			0x0121
#define ZFCP_CT_GPN_FT			0x0172
#define ZFCP_CT_MAX_SIZE		0x1020
#define ZFCP_CT_ACCEPT			0x8002
#define ZFCP_CT_REJECT			0x8001

/*
 * FC-GS-4 stuff
 */
#define ZFCP_CT_TIMEOUT			(3 * R_A_TOV)

/*************** ADAPTER/PORT/UNIT AND FSF_REQ STATUS FLAGS ******************/

/*
 * Note, the leftmost status byte is common among adapter, port
 * and unit
 */
#define ZFCP_COMMON_FLAGS			0xfff00000

/* common status bits */
#define ZFCP_STATUS_COMMON_REMOVE		0x80000000
#define ZFCP_STATUS_COMMON_RUNNING		0x40000000
#define ZFCP_STATUS_COMMON_ERP_FAILED		0x20000000
#define ZFCP_STATUS_COMMON_UNBLOCKED		0x10000000
#define ZFCP_STATUS_COMMON_OPENING              0x08000000
#define ZFCP_STATUS_COMMON_OPEN                 0x04000000
#define ZFCP_STATUS_COMMON_CLOSING              0x02000000
#define ZFCP_STATUS_COMMON_ERP_INUSE		0x01000000
#define ZFCP_STATUS_COMMON_ACCESS_DENIED	0x00800000
#define ZFCP_STATUS_COMMON_ACCESS_BOXED		0x00400000
#define ZFCP_STATUS_COMMON_NOESC		0x00200000

/* adapter status */
#define ZFCP_STATUS_ADAPTER_QDIOUP		0x00000002
#define ZFCP_STATUS_ADAPTER_REGISTERED		0x00000004
#define ZFCP_STATUS_ADAPTER_XCONFIG_OK		0x00000008
#define ZFCP_STATUS_ADAPTER_HOST_CON_INIT	0x00000010
#define ZFCP_STATUS_ADAPTER_ERP_THREAD_UP	0x00000020
#define ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL	0x00000080
#define ZFCP_STATUS_ADAPTER_ERP_PENDING		0x00000100
#define ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED	0x00000200
#define ZFCP_STATUS_ADAPTER_XPORT_OK		0x00000800

/* FC-PH/FC-GS well-known address identifiers for generic services */
#define ZFCP_DID_MANAGEMENT_SERVICE		0xFFFFFA
#define ZFCP_DID_TIME_SERVICE			0xFFFFFB
#define ZFCP_DID_DIRECTORY_SERVICE		0xFFFFFC
#define ZFCP_DID_ALIAS_SERVICE			0xFFFFF8
#define ZFCP_DID_KEY_DISTRIBUTION_SERVICE	0xFFFFF7

/* remote port status */
#define ZFCP_STATUS_PORT_PHYS_OPEN		0x00000001
#define ZFCP_STATUS_PORT_DID_DID		0x00000002
#define ZFCP_STATUS_PORT_PHYS_CLOSING		0x00000004
#define ZFCP_STATUS_PORT_NO_WWPN		0x00000008
#define ZFCP_STATUS_PORT_NO_SCSI_ID		0x00000010
#define ZFCP_STATUS_PORT_INVALID_WWPN		0x00000020

/* for ports with well known addresses */
#define ZFCP_STATUS_PORT_WKA \
		(ZFCP_STATUS_PORT_NO_WWPN | \
		 ZFCP_STATUS_PORT_NO_SCSI_ID)

/* logical unit status */
#define ZFCP_STATUS_UNIT_TEMPORARY		0x00000002
#define ZFCP_STATUS_UNIT_SHARED			0x00000004
#define ZFCP_STATUS_UNIT_READONLY		0x00000008
#define ZFCP_STATUS_UNIT_REGISTERED		0x00000010
#define ZFCP_STATUS_UNIT_SCSI_WORK_PENDING	0x00000020

/* FSF request status (this does not have a common part) */
#define ZFCP_STATUS_FSFREQ_NOT_INIT		0x00000000
#define ZFCP_STATUS_FSFREQ_POOL  		0x00000001
#define ZFCP_STATUS_FSFREQ_TASK_MANAGEMENT	0x00000002
#define ZFCP_STATUS_FSFREQ_COMPLETED		0x00000004
#define ZFCP_STATUS_FSFREQ_ERROR		0x00000008
#define ZFCP_STATUS_FSFREQ_CLEANUP		0x00000010
#define ZFCP_STATUS_FSFREQ_ABORTING		0x00000020
#define ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED	0x00000040
#define ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED       0x00000080
#define ZFCP_STATUS_FSFREQ_ABORTED              0x00000100
#define ZFCP_STATUS_FSFREQ_TMFUNCFAILED         0x00000200
#define ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP        0x00000400
#define ZFCP_STATUS_FSFREQ_RETRY                0x00000800
#define ZFCP_STATUS_FSFREQ_DISMISSED            0x00001000

/*********************** ERROR RECOVERY PROCEDURE DEFINES ********************/

#define ZFCP_MAX_ERPS                   3

#define ZFCP_ERP_FSFREQ_TIMEOUT		(30 * HZ)
#define ZFCP_ERP_MEMWAIT_TIMEOUT	HZ

#define ZFCP_STATUS_ERP_TIMEDOUT	0x10000000
#define ZFCP_STATUS_ERP_CLOSE_ONLY	0x01000000
#define ZFCP_STATUS_ERP_DISMISSING	0x00100000
#define ZFCP_STATUS_ERP_DISMISSED	0x00200000
#define ZFCP_STATUS_ERP_LOWMEM		0x00400000

#define ZFCP_ERP_STEP_UNINITIALIZED	0x00000000
#define ZFCP_ERP_STEP_FSF_XCONFIG	0x00000001
#define ZFCP_ERP_STEP_PHYS_PORT_CLOSING	0x00000010
#define ZFCP_ERP_STEP_PORT_CLOSING	0x00000100
#define ZFCP_ERP_STEP_NAMESERVER_OPEN	0x00000200
#define ZFCP_ERP_STEP_NAMESERVER_LOOKUP	0x00000400
#define ZFCP_ERP_STEP_PORT_OPENING	0x00000800
#define ZFCP_ERP_STEP_UNIT_CLOSING	0x00001000
#define ZFCP_ERP_STEP_UNIT_OPENING	0x00002000

/* Ordered by escalation level (necessary for proper erp-code operation) */
#define ZFCP_ERP_ACTION_REOPEN_ADAPTER		0x4
#define ZFCP_ERP_ACTION_REOPEN_PORT_FORCED	0x3
#define ZFCP_ERP_ACTION_REOPEN_PORT		0x2
#define ZFCP_ERP_ACTION_REOPEN_UNIT		0x1

#define ZFCP_ERP_ACTION_RUNNING			0x1
#define ZFCP_ERP_ACTION_READY			0x2

#define ZFCP_ERP_SUCCEEDED	0x0
#define ZFCP_ERP_FAILED		0x1
#define ZFCP_ERP_CONTINUES	0x2
#define ZFCP_ERP_EXIT		0x3
#define ZFCP_ERP_DISMISSED	0x4
#define ZFCP_ERP_NOMEM		0x5

/************************* STRUCTURE DEFINITIONS *****************************/

struct zfcp_fsf_req;

/* holds various memory pools of an adapter */
struct zfcp_adapter_mempool {
	mempool_t *fsf_req_erp;
	mempool_t *fsf_req_scsi;
	mempool_t *fsf_req_abort;
	mempool_t *fsf_req_status_read;
	mempool_t *data_status_read;
	mempool_t *data_gid_pn;
};

/*
 * header for CT_IU
 */
struct ct_hdr {
	u8 revision;		// 0x01
	u8 in_id[3];		// 0x00
	u8 gs_type;		// 0xFC	Directory Service
	u8 gs_subtype;		// 0x02	Name Server
	u8 options;		// 0x00 single bidirectional exchange
	u8 reserved0;
	u16 cmd_rsp_code;	// 0x0121 GID_PN, or 0x0100 GA_NXT
	u16 max_res_size;	// <= (4096 - 16) / 4
	u8 reserved1;
	u8 reason_code;
	u8 reason_code_expl;
	u8 vendor_unique;
} __attribute__ ((packed));

/* nameserver request CT_IU -- for requests where
 * a port name is required */
struct ct_iu_gid_pn_req {
	struct ct_hdr header;
	wwn_t wwpn;
} __attribute__ ((packed));

/* FS_ACC IU and data unit for GID_PN nameserver request */
struct ct_iu_gid_pn_resp {
	struct ct_hdr header;
	u32 d_id;
} __attribute__ ((packed));

typedef void (*zfcp_send_ct_handler_t)(unsigned long);

/**
 * struct zfcp_send_ct - used to pass parameters to function zfcp_fsf_send_ct
 * @port: port where the request is sent to
 * @req: scatter-gather list for request
 * @resp: scatter-gather list for response
 * @req_count: number of elements in request scatter-gather list
 * @resp_count: number of elements in response scatter-gather list
 * @handler: handler function (called for response to the request)
 * @handler_data: data passed to handler function
 * @timeout: FSF timeout for this request
 * @completion: completion for synchronization purposes
 * @status: used to pass error status to calling function
 */
struct zfcp_send_ct {
	struct zfcp_port *port;
	struct scatterlist *req;
	struct scatterlist *resp;
	unsigned int req_count;
	unsigned int resp_count;
	zfcp_send_ct_handler_t handler;
	unsigned long handler_data;
	int timeout;
	struct completion *completion;
	int status;
};

/* used for name server requests in error recovery */
struct zfcp_gid_pn_data {
	struct zfcp_send_ct ct;
	struct scatterlist req;
	struct scatterlist resp;
	struct ct_iu_gid_pn_req ct_iu_req;
	struct ct_iu_gid_pn_resp ct_iu_resp;
        struct zfcp_port *port;
};

typedef void (*zfcp_send_els_handler_t)(unsigned long);

/**
 * struct zfcp_send_els - used to pass parameters to function zfcp_fsf_send_els
 * @adapter: adapter where request is sent from
 * @port: port where ELS is destinated (port reference count has to be increased)
 * @d_id: destiniation id of port where request is sent to
 * @req: scatter-gather list for request
 * @resp: scatter-gather list for response
 * @req_count: number of elements in request scatter-gather list
 * @resp_count: number of elements in response scatter-gather list
 * @handler: handler function (called for response to the request)
 * @handler_data: data passed to handler function
 * @completion: completion for synchronization purposes
 * @ls_code: hex code of ELS command
 * @status: used to pass error status to calling function
 */
struct zfcp_send_els {
	struct zfcp_adapter *adapter;
	struct zfcp_port *port;
	u32 d_id;
	struct scatterlist *req;
	struct scatterlist *resp;
	unsigned int req_count;
	unsigned int resp_count;
	zfcp_send_els_handler_t handler;
	unsigned long handler_data;
	struct completion *completion;
	int ls_code;
	int status;
};

struct zfcp_qdio_queue {
	struct qdio_buffer *sbal[QDIO_MAX_BUFFERS_PER_Q]; /* SBALs */
	u8		   first;	      /* index of next free bfr
						 in queue (free_count>0) */
	atomic_t           count;	      /* number of free buffers
						 in queue */
	rwlock_t	   lock;	      /* lock for operations on queue */
	int                pci_batch;	      /* SBALs since PCI indication
						 was last set */
};

struct zfcp_erp_action {
	struct list_head list;
	int action;	              /* requested action code */
	struct zfcp_adapter *adapter; /* device which should be recovered */
	struct zfcp_port *port;
	struct zfcp_unit *unit;
	volatile u32 status;	      /* recovery status */
	u32 step;	              /* active step of this erp action */
	struct zfcp_fsf_req *fsf_req; /* fsf request currently pending
					 for this action */
	struct timer_list timer;
};

struct fsf_latency_record {
	u32 min;
	u32 max;
	u64 sum;
};

struct latency_cont {
	struct fsf_latency_record channel;
	struct fsf_latency_record fabric;
	u64 counter;
};

struct zfcp_latencies {
	struct latency_cont read;
	struct latency_cont write;
	struct latency_cont cmd;
	spinlock_t lock;
};

struct zfcp_adapter {
	struct list_head	list;              /* list of adapters */
	atomic_t                refcount;          /* reference count */
	wait_queue_head_t	remove_wq;         /* can be used to wait for
						      refcount drop to zero */
	wwn_t			peer_wwnn;	   /* P2P peer WWNN */
	wwn_t			peer_wwpn;	   /* P2P peer WWPN */
	u32			peer_d_id;	   /* P2P peer D_ID */
	struct ccw_device       *ccw_device;	   /* S/390 ccw device */
	u32			hydra_version;	   /* Hydra version */
	u32			fsf_lic_version;
	u32			adapter_features;  /* FCP channel features */
	u32			connection_features; /* host connection features */
        u32			hardware_version;  /* of FCP channel */
	u16			timer_ticks;       /* time int for a tick */
	struct Scsi_Host	*scsi_host;	   /* Pointer to mid-layer */
	struct list_head	port_list_head;	   /* remote port list */
	struct list_head        port_remove_lh;    /* head of ports to be
						      removed */
	u32			ports;	           /* number of remote ports */
	unsigned long		req_no;		   /* unique FSF req number */
	struct list_head	*req_list;	   /* list of pending reqs */
	spinlock_t		req_list_lock;	   /* request list lock */
	struct zfcp_qdio_queue	req_q;		   /* request queue */
	u32			fsf_req_seq_no;	   /* FSF cmnd seq number */
	wait_queue_head_t	request_wq;	   /* can be used to wait for
						      more avaliable SBALs */
	struct zfcp_qdio_queue	resp_q;	   /* response queue */
	rwlock_t		abort_lock;        /* Protects against SCSI
						      stack abort/command
						      completion races */
	atomic_t		stat_miss;	   /* # missing status reads*/
	struct work_struct	stat_work;
	atomic_t		status;	           /* status of this adapter */
	struct list_head	erp_ready_head;	   /* error recovery for this
						      adapter/devices */
	struct list_head	erp_running_head;
	rwlock_t		erp_lock;
	struct semaphore	erp_ready_sem;
	wait_queue_head_t	erp_thread_wqh;
	wait_queue_head_t	erp_done_wqh;
	struct zfcp_erp_action	erp_action;	   /* pending error recovery */
        atomic_t                erp_counter;
	u32			erp_total_count;   /* total nr of enqueued erp
						      actions */
	u32			erp_low_mem_count; /* nr of erp actions waiting
						      for memory */
	struct zfcp_port	*nameserver_port;  /* adapter's nameserver */
	debug_info_t		*rec_dbf;
	debug_info_t		*hba_dbf;
	debug_info_t		*san_dbf;          /* debug feature areas */
	debug_info_t		*scsi_dbf;
	spinlock_t		rec_dbf_lock;
	spinlock_t		hba_dbf_lock;
	spinlock_t		san_dbf_lock;
	spinlock_t		scsi_dbf_lock;
	struct zfcp_rec_dbf_record	rec_dbf_buf;
	struct zfcp_hba_dbf_record	hba_dbf_buf;
	struct zfcp_san_dbf_record	san_dbf_buf;
	struct zfcp_scsi_dbf_record	scsi_dbf_buf;
	struct zfcp_adapter_mempool	pool;      /* Adapter memory pools */
	struct qdio_initialize  qdio_init_data;    /* for qdio_establish */
	struct device           generic_services;  /* directory for WKA ports */
	struct fc_host_statistics *fc_stats;
	struct fsf_qtcb_bottom_port *stats_reset_data;
	unsigned long		stats_reset;
	struct work_struct	scan_work;
};

/*
 * the struct device sysfs_device must be at the beginning of this structure.
 * pointer to struct device is used to free port structure in release function
 * of the device. don't change!
 */
struct zfcp_port {
	struct device          sysfs_device;   /* sysfs device */
	struct fc_rport        *rport;         /* rport of fc transport class */
	struct list_head       list;	       /* list of remote ports */
	atomic_t               refcount;       /* reference count */
	wait_queue_head_t      remove_wq;      /* can be used to wait for
						  refcount drop to zero */
	struct zfcp_adapter    *adapter;       /* adapter used to access port */
	struct list_head       unit_list_head; /* head of logical unit list */
	struct list_head       unit_remove_lh; /* head of luns to be removed
						  list */
	u32		       units;	       /* # of logical units in list */
	atomic_t	       status;	       /* status of this remote port */
	wwn_t		       wwnn;	       /* WWNN if known */
	wwn_t		       wwpn;	       /* WWPN */
	u32		       d_id;	       /* D_ID */
	u32		       handle;	       /* handle assigned by FSF */
	struct zfcp_erp_action erp_action;     /* pending error recovery */
        atomic_t               erp_counter;
	u32                    maxframe_size;
	u32                    supported_classes;
};

/* the struct device sysfs_device must be at the beginning of this structure.
 * pointer to struct device is used to free unit structure in release function
 * of the device. don't change!
 */
struct zfcp_unit {
	struct device          sysfs_device;   /* sysfs device */
	struct list_head       list;	       /* list of logical units */
	atomic_t               refcount;       /* reference count */
	wait_queue_head_t      remove_wq;      /* can be used to wait for
						  refcount drop to zero */
	struct zfcp_port       *port;	       /* remote port of unit */
	atomic_t	       status;	       /* status of this logical unit */
	unsigned int	       scsi_lun;       /* own SCSI LUN */
	fcp_lun_t	       fcp_lun;	       /* own FCP_LUN */
	u32		       handle;	       /* handle assigned by FSF */
        struct scsi_device     *device;        /* scsi device struct pointer */
	struct zfcp_erp_action erp_action;     /* pending error recovery */
        atomic_t               erp_counter;
	struct zfcp_latencies	latencies;
};

/* FSF request */
struct zfcp_fsf_req {
	struct list_head       list;	       /* list of FSF requests */
	unsigned long	       req_id;	       /* unique request ID */
	struct zfcp_adapter    *adapter;       /* adapter request belongs to */
	u8		       sbal_number;    /* nr of SBALs free for use */
	u8		       sbal_first;     /* first SBAL for this request */
	u8		       sbal_last;      /* last SBAL for this request */
	u8		       sbal_limit;      /* last possible SBAL for
						  this reuest */
	u8		       sbale_curr;     /* current SBALE during creation
						  of request */
	u8			sbal_response;	/* SBAL used in interrupt */
	wait_queue_head_t      completion_wq;  /* can be used by a routine
						  to wait for completion */
	volatile u32	       status;	       /* status of this request */
	u32		       fsf_command;    /* FSF Command copy */
	struct fsf_qtcb	       *qtcb;	       /* address of associated QTCB */
	u32		       seq_no;         /* Sequence number of request */
	unsigned long	       data;           /* private data of request */
	struct timer_list     timer;	       /* used for erp or scsi er */
	struct zfcp_erp_action *erp_action;    /* used if this request is
						  issued on behalf of erp */
	mempool_t	       *pool;	       /* used if request was alloacted
						  from emergency pool */
	unsigned long long     issued;         /* request sent time (STCK) */
	struct zfcp_unit       *unit;
};

typedef void zfcp_fsf_req_handler_t(struct zfcp_fsf_req*);

/* driver data */
struct zfcp_data {
	struct scsi_host_template scsi_host_template;
	struct scsi_transport_template *scsi_transport_template;
        atomic_t                status;             /* Module status flags */
	struct list_head	adapter_list_head;  /* head of adapter list */
	struct list_head	adapter_remove_lh;  /* head of adapters to be
						       removed */
	u32			adapters;	    /* # of adapters in list */
	rwlock_t                config_lock;        /* serialises changes
						       to adapter/port/unit
						       lists */
	struct semaphore        config_sema;        /* serialises configuration
						       changes */
	atomic_t		loglevel;            /* current loglevel */
	char                    init_busid[BUS_ID_SIZE];
	wwn_t                   init_wwpn;
	fcp_lun_t               init_fcp_lun;
	struct kmem_cache		*fsf_req_qtcb_cache;
	struct kmem_cache		*sr_buffer_cache;
	struct kmem_cache		*gid_pn_cache;
};

/* number of elements for various memory pools */
#define ZFCP_POOL_FSF_REQ_ERP_NR	1
#define ZFCP_POOL_FSF_REQ_SCSI_NR	1
#define ZFCP_POOL_FSF_REQ_ABORT_NR	1
#define ZFCP_POOL_STATUS_READ_NR	ZFCP_STATUS_READS_RECOM
#define ZFCP_POOL_DATA_GID_PN_NR	1

/* struct used by memory pools for fsf_requests */
struct zfcp_fsf_req_qtcb {
	struct zfcp_fsf_req fsf_req;
	struct fsf_qtcb qtcb;
};

/********************** ZFCP SPECIFIC DEFINES ********************************/

#define ZFCP_REQ_AUTO_CLEANUP	0x00000002
#define ZFCP_WAIT_FOR_SBAL	0x00000004
#define ZFCP_REQ_NO_QTCB	0x00000008

#define ZFCP_SET                0x00000100
#define ZFCP_CLEAR              0x00000200

#ifndef atomic_test_mask
#define atomic_test_mask(mask, target) \
           ((atomic_read(target) & mask) == mask)
#endif

extern void _zfcp_hex_dump(char *, int);
#define ZFCP_HEX_DUMP(level, addr, count) \
		if (ZFCP_LOG_CHECK(level)) { \
			_zfcp_hex_dump(addr, count); \
		}

#define zfcp_get_busid_by_adapter(adapter) (adapter->ccw_device->dev.bus_id)
#define zfcp_get_busid_by_port(port) (zfcp_get_busid_by_adapter(port->adapter))
#define zfcp_get_busid_by_unit(unit) (zfcp_get_busid_by_port(unit->port))

/*
 * Helper functions for request ID management.
 */
static inline int zfcp_reqlist_hash(unsigned long req_id)
{
	return req_id % REQUEST_LIST_SIZE;
}

static inline void zfcp_reqlist_add(struct zfcp_adapter *adapter,
				    struct zfcp_fsf_req *fsf_req)
{
	unsigned int idx;

	idx = zfcp_reqlist_hash(fsf_req->req_id);
	list_add_tail(&fsf_req->list, &adapter->req_list[idx]);
}

static inline void zfcp_reqlist_remove(struct zfcp_adapter *adapter,
				       struct zfcp_fsf_req *fsf_req)
{
	list_del(&fsf_req->list);
}

static inline struct zfcp_fsf_req *
zfcp_reqlist_find(struct zfcp_adapter *adapter, unsigned long req_id)
{
	struct zfcp_fsf_req *request;
	unsigned int idx;

	idx = zfcp_reqlist_hash(req_id);
	list_for_each_entry(request, &adapter->req_list[idx], list)
		if (request->req_id == req_id)
			return request;
	return NULL;
}

static inline struct zfcp_fsf_req *
zfcp_reqlist_find_safe(struct zfcp_adapter *adapter, struct zfcp_fsf_req *req)
{
	struct zfcp_fsf_req *request;
	unsigned int idx;

	for (idx = 0; idx < REQUEST_LIST_SIZE; idx++) {
		list_for_each_entry(request, &adapter->req_list[idx], list)
			if (request == req)
				return request;
	}
	return NULL;
}

/*
 *  functions needed for reference/usage counting
 */

static inline void
zfcp_unit_get(struct zfcp_unit *unit)
{
	atomic_inc(&unit->refcount);
}

static inline void
zfcp_unit_put(struct zfcp_unit *unit)
{
	if (atomic_dec_return(&unit->refcount) == 0)
		wake_up(&unit->remove_wq);
}

static inline void
zfcp_unit_wait(struct zfcp_unit *unit)
{
	wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
}

static inline void
zfcp_port_get(struct zfcp_port *port)
{
	atomic_inc(&port->refcount);
}

static inline void
zfcp_port_put(struct zfcp_port *port)
{
	if (atomic_dec_return(&port->refcount) == 0)
		wake_up(&port->remove_wq);
}

static inline void
zfcp_port_wait(struct zfcp_port *port)
{
	wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
}

static inline void
zfcp_adapter_get(struct zfcp_adapter *adapter)
{
	atomic_inc(&adapter->refcount);
}

static inline void
zfcp_adapter_put(struct zfcp_adapter *adapter)
{
	if (atomic_dec_return(&adapter->refcount) == 0)
		wake_up(&adapter->remove_wq);
}

static inline void
zfcp_adapter_wait(struct zfcp_adapter *adapter)
{
	wait_event(adapter->remove_wq, atomic_read(&adapter->refcount) == 0);
}

#endif /* ZFCP_DEF_H */