aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/s390/scsi/zfcp_def.h
blob: 99830758e873ff8eadc55954f61e8bf5e0ee2124 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
/*
 * zfcp device driver
 *
 * Global definitions for the zfcp device driver.
 *
 * Copyright IBM Corporation 2002, 2009
 */

#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/fc/fc_fs.h>
#include <scsi/fc/fc_gs.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 <scsi/scsi_bsg_fc.h>
#include <asm/ccwdev.h>
#include <asm/qdio.h>
#include <asm/debug.h>
#include <asm/ebcdic.h>
#include <asm/sysinfo.h>
#include "zfcp_fsf.h"

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

#define REQUEST_LIST_SIZE 128

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

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

/* 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		\
	(FSF_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 */

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

/* ATTENTION: value must not be used by hardware */
#define FSF_QTCB_UNSOLICITED_STATUS		0x6305

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

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

/* 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 {
	u64 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));

/* see fc-ph */
struct fcp_logo {
        u32 command;
        u32 nport_did;
	u64 nport_wwpn;
} __attribute__((packed));

/*
 * FC-FS stuff
 */
#define R_A_TOV				10 /* seconds */

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

/*
 * 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_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_OPEN                 0x04000000
#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_XCONFIG_OK		0x00000008
#define ZFCP_STATUS_ADAPTER_HOST_CON_INIT	0x00000010
#define ZFCP_STATUS_ADAPTER_ERP_PENDING		0x00000100
#define ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED	0x00000200

/* FC-PH/FC-GS well-known address identifiers for generic services */
#define ZFCP_DID_WKA				0xFFFFF0

/* remote port status */
#define ZFCP_STATUS_PORT_PHYS_OPEN		0x00000001
#define ZFCP_STATUS_PORT_LINK_TEST		0x00000002

/* well known address (WKA) port status*/
enum zfcp_wka_status {
	ZFCP_WKA_PORT_OFFLINE,
	ZFCP_WKA_PORT_CLOSING,
	ZFCP_WKA_PORT_OPENING,
	ZFCP_WKA_PORT_ONLINE,
};

/* logical unit status */
#define ZFCP_STATUS_UNIT_SHARED			0x00000004
#define ZFCP_STATUS_UNIT_READONLY		0x00000008

/* FSF request status (this does not have a common part) */
#define ZFCP_STATUS_FSFREQ_TASK_MANAGEMENT	0x00000002
#define ZFCP_STATUS_FSFREQ_ERROR		0x00000008
#define ZFCP_STATUS_FSFREQ_CLEANUP		0x00000010
#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

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

struct zfcp_fsf_req;

/* holds various memory pools of an adapter */
struct zfcp_adapter_mempool {
	mempool_t *erp_req;
	mempool_t *gid_pn_req;
	mempool_t *scsi_req;
	mempool_t *scsi_abort;
	mempool_t *status_read_req;
	mempool_t *status_read_data;
	mempool_t *gid_pn_data;
	mempool_t *qtcb_pool;
};

/*
 * 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;
	u64 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));

struct ct_iu_gpn_ft_req {
	struct ct_hdr header;
	u8 flags;
	u8 domain_id_scope;
	u8 area_id_scope;
	u8 fc4_type;
} __attribute__ ((packed));


/**
 * struct zfcp_send_ct - used to pass parameters to function zfcp_fsf_send_ct
 * @wka_port: port where the request is sent to
 * @req: scatter-gather list for request
 * @resp: scatter-gather list for response
 * @handler: handler function (called for response to the request)
 * @handler_data: data passed to handler function
 * @completion: completion for synchronization purposes
 * @status: used to pass error status to calling function
 */
struct zfcp_send_ct {
	struct zfcp_wka_port *wka_port;
	struct scatterlist *req;
	struct scatterlist *resp;
	void (*handler)(unsigned long);
	unsigned long handler_data;
	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;
};

/**
 * 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
 * @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;
	void (*handler)(unsigned long);
	unsigned long handler_data;
	struct completion *completion;
	int ls_code;
	int status;
};

struct zfcp_wka_port {
	struct zfcp_adapter	*adapter;
	wait_queue_head_t	completion_wq;
	enum zfcp_wka_status	status;
	atomic_t		refcount;
	u32			d_id;
	u32			handle;
	struct mutex		mutex;
	struct delayed_work	work;
};

struct zfcp_wka_ports {
	struct zfcp_wka_port ms; 	/* management service */
	struct zfcp_wka_port ts; 	/* time service */
	struct zfcp_wka_port ds; 	/* directory service */
	struct zfcp_wka_port as; 	/* alias service */
	struct zfcp_wka_port ks; 	/* key distribution service */
};

struct zfcp_qdio_queue {
	struct qdio_buffer *sbal[QDIO_MAX_BUFFERS_PER_Q];
	u8		   first;	/* index of next free bfr in queue */
	atomic_t           count;	/* number of free buffers in queue */
};

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;
	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_qdio - basic QDIO data structure
 * @resp_q: response queue
 * @req_q: request queue
 * @stat_lock: lock to protect req_q_util and req_q_time
 * @req_q_lock; lock to serialize access to request queue
 * @req_q_time: time of last fill level change
 * @req_q_util: used for accounting
 * @req_q_full: queue full incidents
 * @req_q_wq: used to wait for SBAL availability
 * @adapter: adapter used in conjunction with this QDIO structure
 */
struct zfcp_qdio {
	struct zfcp_qdio_queue	resp_q;
	struct zfcp_qdio_queue	req_q;
	spinlock_t		stat_lock;
	spinlock_t		req_q_lock;
	ktime_t			req_q_time;
	u64			req_q_util;
	atomic_t		req_q_full;
	wait_queue_head_t	req_q_wq;
	struct zfcp_adapter	*adapter;
};

struct zfcp_adapter {
	atomic_t                refcount;          /* reference count */
	wait_queue_head_t	remove_wq;         /* can be used to wait for
						      refcount drop to zero */
	u64			peer_wwnn;	   /* P2P peer WWNN */
	u64			peer_wwpn;	   /* P2P peer WWPN */
	u32			peer_d_id;	   /* P2P peer D_ID */
	struct ccw_device       *ccw_device;	   /* S/390 ccw device */
	struct zfcp_qdio	*qdio;
	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 */
	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 */
	u32			fsf_req_seq_no;	   /* FSF cmnd seq number */
	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 */
	wait_queue_head_t	erp_ready_wq;
	struct list_head	erp_running_head;
	rwlock_t		erp_lock;
	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 task_struct	*erp_thread;
	struct zfcp_wka_ports	*gs;		   /* generic services */
	struct zfcp_dbf		*dbf;		   /* debug traces */
	struct zfcp_adapter_mempool	pool;      /* Adapter memory pools */
	struct fc_host_statistics *fc_stats;
	struct fsf_qtcb_bottom_port *stats_reset_data;
	unsigned long		stats_reset;
	struct work_struct	scan_work;
	struct service_level	service_level;
	struct workqueue_struct	*work_queue;
};

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 */
	atomic_t	       status;	       /* status of this remote port */
	u64		       wwnn;	       /* WWNN if known */
	u64		       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;
	struct work_struct     gid_pn_work;
	struct work_struct     test_link_work;
	struct work_struct     rport_work;
	enum { RPORT_NONE, RPORT_ADD, RPORT_DEL }  rport_task;
};

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 */
	u64		       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;
	struct work_struct	scsi_work;
};

/**
 * struct zfcp_queue_req - queue related values for a request
 * @sbal_number: number of free SBALs
 * @sbal_first: first SBAL for this request
 * @sbal_last: last SBAL for this request
 * @sbal_limit: last possible SBAL for this request
 * @sbale_curr: current SBALE at creation of this request
 * @sbal_response: SBAL used in interrupt
 * @qdio_outb_usage: usage of outbound queue
 * @qdio_inb_usage: usage of inbound queue
 */
struct zfcp_queue_req {
	u8		       sbal_number;
	u8		       sbal_first;
	u8		       sbal_last;
	u8		       sbal_limit;
	u8		       sbale_curr;
	u8		       sbal_response;
	u16		       qdio_outb_usage;
	u16		       qdio_inb_usage;
};

/**
 * struct zfcp_fsf_req - basic FSF request structure
 * @list: list of FSF requests
 * @req_id: unique request ID
 * @adapter: adapter this request belongs to
 * @queue_req: queue related values
 * @completion: used to signal the completion of the request
 * @status: status of the request
 * @fsf_command: FSF command issued
 * @qtcb: associated QTCB
 * @seq_no: sequence number of this request
 * @data: private data
 * @timer: timer data of this request
 * @erp_action: reference to erp action if request issued on behalf of ERP
 * @pool: reference to memory pool if used for this request
 * @issued: time when request was send (STCK)
 * @unit: reference to unit if this request is a SCSI request
 * @handler: handler which should be called to process response
 */
struct zfcp_fsf_req {
	struct list_head	list;
	unsigned long		req_id;
	struct zfcp_adapter	*adapter;
	struct zfcp_queue_req	queue_req;
	struct completion	completion;
	u32			status;
	u32			fsf_command;
	struct fsf_qtcb		*qtcb;
	u32			seq_no;
	void			*data;
	struct timer_list	timer;
	struct zfcp_erp_action	*erp_action;
	mempool_t		*pool;
	unsigned long long	issued;
	struct zfcp_unit	*unit;
	void			(*handler)(struct zfcp_fsf_req *);
};

/* driver data */
struct zfcp_data {
	struct scsi_host_template scsi_host_template;
	struct scsi_transport_template *scsi_transport_template;
	rwlock_t                config_lock;        /* serialises changes
						       to adapter/port/unit
						       lists */
	struct semaphore        config_sema;        /* serialises configuration
						       changes */
	struct kmem_cache	*gpn_ft_cache;
	struct kmem_cache	*qtcb_cache;
	struct kmem_cache	*sr_buffer_cache;
	struct kmem_cache	*gid_pn_cache;
};

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

#define ZFCP_SET                0x00000100
#define ZFCP_CLEAR              0x00000200

/*
 * 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_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_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_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);
}

#endif /* ZFCP_DEF_H */