summaryrefslogtreecommitdiff
path: root/drivers/s390/scsi/zfcp_scsi.c
blob: be7c91d4ae8c49aafea65f2eab7c8cf5c69739cc (plain)
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
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
/* 
 * 
 * linux/drivers/s390/scsi/zfcp_scsi.c
 * 
 * FCP adapter driver for IBM eServer zSeries 
 * 
 * (C) Copyright IBM Corp. 2002, 2004
 *
 * Author(s): Martin Peschke <mpeschke@de.ibm.com> 
 *            Raimund Schroeder <raimund.schroeder@de.ibm.com> 
 *            Aron Zeh
 *            Wolfgang Taphorn
 *            Stefan Bader <stefan.bader@de.ibm.com> 
 *            Heiko Carstens <heiko.carstens@de.ibm.com> 
 *            Andreas Herrmann <aherrman@de.ibm.com>
 * 
 * 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; if not, write to the Free Software 
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
 */

#define ZFCP_LOG_AREA			ZFCP_LOG_AREA_SCSI

#define ZFCP_SCSI_REVISION "$Revision: 1.74 $"

#include "zfcp_ext.h"

static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
				  void (*done) (struct scsi_cmnd *));
static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
static int zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *);
static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
static int zfcp_task_management_function(struct zfcp_unit *, u8);

static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
					  scsi_lun_t);
static struct zfcp_port *zfcp_port_lookup(struct zfcp_adapter *, int,
					  scsi_id_t);

static struct device_attribute *zfcp_sysfs_sdev_attrs[];

struct scsi_transport_template *zfcp_transport_template;

struct zfcp_data zfcp_data = {
	.scsi_host_template = {
	      name:	               ZFCP_NAME,
	      proc_name:               "zfcp",
	      proc_info:               NULL,
	      detect:	               NULL,
	      slave_alloc:             zfcp_scsi_slave_alloc,
	      slave_configure:         zfcp_scsi_slave_configure,
	      slave_destroy:           zfcp_scsi_slave_destroy,
	      queuecommand:            zfcp_scsi_queuecommand,
	      eh_abort_handler:        zfcp_scsi_eh_abort_handler,
	      eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
	      eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
	      eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
			               /* FIXME(openfcp): Tune */
	      can_queue:               4096,
	      this_id:	               0,
	      /*
	       * FIXME:
	       * one less? can zfcp_create_sbale cope with it?
	       */
	      sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
	      cmd_per_lun:             1,
	      unchecked_isa_dma:       0,
	      use_clustering:          1,
	      sdev_attrs:              zfcp_sysfs_sdev_attrs,
	},
	.driver_version = ZFCP_VERSION,
	/* rest initialised with zeros */
};

/* Find start of Response Information in FCP response unit*/
char *
zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
{
	char *fcp_rsp_info_ptr;

	fcp_rsp_info_ptr =
	    (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));

	return fcp_rsp_info_ptr;
}

/* Find start of Sense Information in FCP response unit*/
char *
zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
{
	char *fcp_sns_info_ptr;

	fcp_sns_info_ptr =
	    (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
	if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
		fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
		    fcp_rsp_iu->fcp_rsp_len;

	return fcp_sns_info_ptr;
}

fcp_dl_t *
zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
{
	int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
	fcp_dl_t *fcp_dl_addr;

	fcp_dl_addr = (fcp_dl_t *)
		((unsigned char *) fcp_cmd +
		 sizeof (struct fcp_cmnd_iu) + additional_length);
	/*
	 * fcp_dl_addr = start address of fcp_cmnd structure + 
	 * size of fixed part + size of dynamically sized add_dcp_cdb field
	 * SEE FCP-2 documentation
	 */
	return fcp_dl_addr;
}

fcp_dl_t
zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
{
	return *zfcp_get_fcp_dl_ptr(fcp_cmd);
}

void
zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
{
	*zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
}

/*
 * note: it's a bit-or operation not an assignment
 * regarding the specified byte
 */
static inline void
set_byte(u32 * result, char status, char pos)
{
	*result |= status << (pos * 8);
}

void
set_host_byte(u32 * result, char status)
{
	set_byte(result, status, 2);
}

void
set_driver_byte(u32 * result, char status)
{
	set_byte(result, status, 3);
}

/*
 * function:	zfcp_scsi_slave_alloc
 *
 * purpose:
 *
 * returns:
 */

static int
zfcp_scsi_slave_alloc(struct scsi_device *sdp)
{
	struct zfcp_adapter *adapter;
	struct zfcp_unit *unit;
	unsigned long flags;
	int retval = -ENODEV;

	adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
	if (!adapter)
		goto out;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
	if (unit) {
		sdp->hostdata = unit;
		unit->device = sdp;
		zfcp_unit_get(unit);
		retval = 0;
	}
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 out:
	return retval;
}

/*
 * function:	zfcp_scsi_slave_destroy
 *
 * purpose:
 *
 * returns:
 */

static void
zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
{
	struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;

	if (unit) {
		sdpnt->hostdata = NULL;
		unit->device = NULL;
		zfcp_unit_put(unit);
	} else {
		ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
				"address %p\n", sdpnt);
	}
}

/* 
 * called from scsi midlayer to allow finetuning of a device.
 */
static int
zfcp_scsi_slave_configure(struct scsi_device *sdp)
{
	if (sdp->tagged_supported)
		scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
	else
		scsi_adjust_queue_depth(sdp, 0, 1);
	return 0;
}

/**
 * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
 * @scpnt: pointer to struct scsi_cmnd where result is set
 * @result: result to be set in scpnt (e.g. DID_ERROR)
 */
static void
zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
{
	set_host_byte(&scpnt->result, result);
	zfcp_cmd_dbf_event_scsi("failing", scpnt);
	/* return directly */
	scpnt->scsi_done(scpnt);
}

/**
 * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
 *	zfcp_scsi_command_sync
 * @adapter: adapter where scsi command is issued
 * @unit: unit to which scsi command is sent
 * @scpnt: scsi command to be sent
 * @timer: timer to be started if request is successfully initiated
 *
 * Note: In scsi_done function must be set in scpnt.
 */
int
zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
			struct scsi_cmnd *scpnt, struct timer_list *timer)
{
	int tmp;
	int retval;

	retval = 0;

	BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
	BUG_ON(scpnt->scsi_done == NULL);

	if (unlikely(NULL == unit)) {
		zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
		goto out;
	}

	if (unlikely(
	      atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
	     !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
		ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
			       "0x%016Lx on adapter %s\n",
			       unit->fcp_lun, unit->port->wwpn,
			       zfcp_get_busid_by_adapter(adapter));
		zfcp_scsi_command_fail(scpnt, DID_ERROR);
		goto out;
	}

	if (unlikely(
	     !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
		ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
			       "on port 0x%016Lx in recovery\n",
			       zfcp_get_busid_by_unit(unit),
			       unit->fcp_lun, unit->port->wwpn);
		retval = SCSI_MLQUEUE_DEVICE_BUSY;
		goto out;
	}

	tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, timer,
					     ZFCP_REQ_AUTO_CLEANUP);

	if (unlikely(tmp < 0)) {
		ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
		retval = SCSI_MLQUEUE_HOST_BUSY;
	}

out:
	return retval;
}

void
zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
{
	struct completion *wait = (struct completion *) scpnt->SCp.ptr;
	complete(wait);
}


/**
 * zfcp_scsi_command_sync - send a SCSI command and wait for completion
 * @unit: unit where command is sent to
 * @scpnt: scsi command to be sent
 * @timer: timer to be started if request is successfully initiated
 * Return: 0
 *
 * Errors are indicated in scpnt->result
 */
int
zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
		       struct timer_list *timer)
{
	int ret;
	DECLARE_COMPLETION(wait);

	scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
	scpnt->scsi_done = zfcp_scsi_command_sync_handler;
	ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt, timer);
	if (ret == 0)
		wait_for_completion(&wait);

	scpnt->SCp.ptr = NULL;

	return 0;
}

/*
 * function:	zfcp_scsi_queuecommand
 *
 * purpose:	enqueues a SCSI command to the specified target device
 *
 * returns:	0 - success, SCSI command enqueued
 *		!0 - failure
 */
int
zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
		       void (*done) (struct scsi_cmnd *))
{
	struct zfcp_unit *unit;
	struct zfcp_adapter *adapter;

	/* reset the status for this request */
	scpnt->result = 0;
	scpnt->host_scribble = NULL;
	scpnt->scsi_done = done;

	/*
	 * figure out adapter and target device
	 * (stored there by zfcp_scsi_slave_alloc)
	 */
	adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
	unit = (struct zfcp_unit *) scpnt->device->hostdata;

	return zfcp_scsi_command_async(adapter, unit, scpnt, NULL);
}

/*
 * function:    zfcp_unit_lookup
 *
 * purpose:
 *
 * returns:
 *
 * context:	
 */
static struct zfcp_unit *
zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
		 scsi_lun_t lun)
{
	struct zfcp_port *port;
	struct zfcp_unit *unit, *retval = NULL;

	list_for_each_entry(port, &adapter->port_list_head, list) {
		if (id != port->scsi_id)
			continue;
		list_for_each_entry(unit, &port->unit_list_head, list) {
			if (lun == unit->scsi_lun) {
				retval = unit;
				goto out;
			}
		}
	}
 out:
	return retval;
}

static struct zfcp_port *
zfcp_port_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id)
{
	struct zfcp_port *port;

	list_for_each_entry(port, &adapter->port_list_head, list) {
		if (id == port->scsi_id)
			return port;
	}
	return (struct zfcp_port *) NULL;
}

/*
 * function:	zfcp_scsi_eh_abort_handler
 *
 * purpose:	tries to abort the specified (timed out) SCSI command
 *
 * note: 	We do not need to care for a SCSI command which completes
 *		normally but late during this abort routine runs.
 *		We are allowed to return late commands to the SCSI stack.
 *		It tracks the state of commands and will handle late commands.
 *		(Usually, the normal completion of late commands is ignored with
 *		respect to the running abort operation. Grep for 'done_late'
 *		in the SCSI stacks sources.)
 *
 * returns:	SUCCESS	- command has been aborted and cleaned up in internal
 *			  bookkeeping,
 *			  SCSI stack won't be called for aborted command
 *		FAILED	- otherwise
 */
int
__zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
{
	int retval = SUCCESS;
	struct zfcp_fsf_req *new_fsf_req, *old_fsf_req;
	struct zfcp_adapter *adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
	struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
	struct zfcp_port *port = unit->port;
	struct Scsi_Host *scsi_host = scpnt->device->host;
	union zfcp_req_data *req_data = NULL;
	unsigned long flags;
	u32 status = 0;

	/* the components of a abort_dbf record (fixed size record) */
	u64 dbf_scsi_cmnd = (unsigned long) scpnt;
	char dbf_opcode[ZFCP_ABORT_DBF_LENGTH];
	wwn_t dbf_wwn = port->wwpn;
	fcp_lun_t dbf_fcp_lun = unit->fcp_lun;
	u64 dbf_retries = scpnt->retries;
	u64 dbf_allowed = scpnt->allowed;
	u64 dbf_timeout = 0;
	u64 dbf_fsf_req = 0;
	u64 dbf_fsf_status = 0;
	u64 dbf_fsf_qual[2] = { 0, 0 };
	char dbf_result[ZFCP_ABORT_DBF_LENGTH] = "##undef";

	memset(dbf_opcode, 0, ZFCP_ABORT_DBF_LENGTH);
	memcpy(dbf_opcode,
	       scpnt->cmnd,
	       min(scpnt->cmd_len, (unsigned char) ZFCP_ABORT_DBF_LENGTH));

	ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
		      scpnt, zfcp_get_busid_by_adapter(adapter));

	spin_unlock_irq(scsi_host->host_lock);

	/*
	 * Race condition between normal (late) completion and abort has
	 * to be avoided.
	 * The entirity of all accesses to scsi_req have to be atomic.
	 * scsi_req is usually part of the fsf_req and thus we block the
	 * release of fsf_req as long as we need to access scsi_req.
	 */
	write_lock_irqsave(&adapter->abort_lock, flags);

	/*
	 * Check whether command has just completed and can not be aborted.
	 * Even if the command has just been completed late, we can access
	 * scpnt since the SCSI stack does not release it at least until
	 * this routine returns. (scpnt is parameter passed to this routine
	 * and must not disappear during abort even on late completion.)
	 */
	req_data = (union zfcp_req_data *) scpnt->host_scribble;
	/* DEBUG */
	ZFCP_LOG_DEBUG("req_data=%p\n", req_data);
	if (!req_data) {
		ZFCP_LOG_DEBUG("late command completion overtook abort\n");
		/*
		 * That's it.
		 * Do not initiate abort but return SUCCESS.
		 */
		write_unlock_irqrestore(&adapter->abort_lock, flags);
		retval = SUCCESS;
		strncpy(dbf_result, "##late1", ZFCP_ABORT_DBF_LENGTH);
		goto out;
	}

	/* Figure out which fsf_req needs to be aborted. */
	old_fsf_req = req_data->send_fcp_command_task.fsf_req;

	dbf_fsf_req = (unsigned long) old_fsf_req;
	dbf_timeout =
	    (jiffies - req_data->send_fcp_command_task.start_jiffies) / HZ;

	ZFCP_LOG_DEBUG("old_fsf_req=%p\n", old_fsf_req);
	if (!old_fsf_req) {
		write_unlock_irqrestore(&adapter->abort_lock, flags);
		ZFCP_LOG_NORMAL("bug: no old fsf request found\n");
		ZFCP_LOG_NORMAL("req_data:\n");
		ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
			      (char *) req_data, sizeof (union zfcp_req_data));
		ZFCP_LOG_NORMAL("scsi_cmnd:\n");
		ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
			      (char *) scpnt, sizeof (struct scsi_cmnd));
		retval = FAILED;
		strncpy(dbf_result, "##bug:r", ZFCP_ABORT_DBF_LENGTH);
		goto out;
	}
	old_fsf_req->data.send_fcp_command_task.scsi_cmnd = NULL;
	/* mark old request as being aborted */
	old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
	/*
	 * We have to collect all information (e.g. unit) needed by 
	 * zfcp_fsf_abort_fcp_command before calling that routine
	 * since that routine is not allowed to access
	 * fsf_req which it is going to abort.
	 * This is because of we need to release fsf_req_list_lock
	 * before calling zfcp_fsf_abort_fcp_command.
	 * Since this lock will not be held, fsf_req may complete
	 * late and may be released meanwhile.
	 */
	ZFCP_LOG_DEBUG("unit 0x%016Lx (%p)\n", unit->fcp_lun, unit);

	/*
	 * We block (call schedule)
	 * That's why we must release the lock and enable the
	 * interrupts before.
	 * On the other hand we do not need the lock anymore since
	 * all critical accesses to scsi_req are done.
	 */
	write_unlock_irqrestore(&adapter->abort_lock, flags);
	/* call FSF routine which does the abort */
	new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
						 adapter, unit, 0);
	ZFCP_LOG_DEBUG("new_fsf_req=%p\n", new_fsf_req);
	if (!new_fsf_req) {
		retval = FAILED;
		ZFCP_LOG_NORMAL("error: initiation of Abort FCP Cmnd "
				"failed\n");
		strncpy(dbf_result, "##nores", ZFCP_ABORT_DBF_LENGTH);
		goto out;
	}

	/* wait for completion of abort */
	ZFCP_LOG_DEBUG("waiting for cleanup...\n");
#if 1
	/*
	 * FIXME:
	 * copying zfcp_fsf_req_wait_and_cleanup code is not really nice
	 */
	__wait_event(new_fsf_req->completion_wq,
		     new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
	status = new_fsf_req->status;
	dbf_fsf_status = new_fsf_req->qtcb->header.fsf_status;
	/*
	 * Ralphs special debug load provides timestamps in the FSF
	 * status qualifier. This might be specified later if being
	 * useful for debugging aborts.
	 */
	dbf_fsf_qual[0] =
	    *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[0];
	dbf_fsf_qual[1] =
	    *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[2];
	zfcp_fsf_req_free(new_fsf_req);
#else
	retval = zfcp_fsf_req_wait_and_cleanup(new_fsf_req,
					       ZFCP_UNINTERRUPTIBLE, &status);
#endif
	ZFCP_LOG_DEBUG("Waiting for cleanup complete, status=0x%x\n", status);
	/* status should be valid since signals were not permitted */
	if (status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
		retval = SUCCESS;
		strncpy(dbf_result, "##succ", ZFCP_ABORT_DBF_LENGTH);
	} else if (status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
		retval = SUCCESS;
		strncpy(dbf_result, "##late2", ZFCP_ABORT_DBF_LENGTH);
	} else {
		retval = FAILED;
		strncpy(dbf_result, "##fail", ZFCP_ABORT_DBF_LENGTH);
	}

 out:
	debug_event(adapter->abort_dbf, 1, &dbf_scsi_cmnd, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_opcode, ZFCP_ABORT_DBF_LENGTH);
	debug_event(adapter->abort_dbf, 1, &dbf_wwn, sizeof (wwn_t));
	debug_event(adapter->abort_dbf, 1, &dbf_fcp_lun, sizeof (fcp_lun_t));
	debug_event(adapter->abort_dbf, 1, &dbf_retries, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_allowed, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_timeout, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_fsf_req, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_fsf_status, sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[0], sizeof (u64));
	debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[1], sizeof (u64));
	debug_text_event(adapter->abort_dbf, 1, dbf_result);

	spin_lock_irq(scsi_host->host_lock);
	return retval;
}

int
zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
{
	int rc;
	struct Scsi_Host *scsi_host = scpnt->device->host;
	spin_lock_irq(scsi_host->host_lock);
	rc = __zfcp_scsi_eh_abort_handler(scpnt);
	spin_unlock_irq(scsi_host->host_lock);
	return rc;
}

/*
 * function:	zfcp_scsi_eh_device_reset_handler
 *
 * purpose:
 *
 * returns:
 */
int
zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
{
	int retval;
	struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
	struct Scsi_Host *scsi_host = scpnt->device->host;

	if (!unit) {
		ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
		retval = SUCCESS;
		goto out;
	}
	ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);

	/*
	 * If we do not know whether the unit supports 'logical unit reset'
	 * then try 'logical unit reset' and proceed with 'target reset'
	 * if 'logical unit reset' fails.
	 * If the unit is known not to support 'logical unit reset' then
	 * skip 'logical unit reset' and try 'target reset' immediately.
	 */
	if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
			      &unit->status)) {
		retval =
		    zfcp_task_management_function(unit, FCP_LOGICAL_UNIT_RESET);
		if (retval) {
			ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
			if (retval == -ENOTSUPP)
				atomic_set_mask
				    (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
				     &unit->status);
			/* fall through and try 'target reset' next */
		} else {
			ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
				       unit);
			/* avoid 'target reset' */
			retval = SUCCESS;
			goto out;
		}
	}
	retval = zfcp_task_management_function(unit, FCP_TARGET_RESET);
	if (retval) {
		ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
		retval = FAILED;
	} else {
		ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
		retval = SUCCESS;
	}
 out:
	return retval;
}

static int
zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags)
{
	struct zfcp_adapter *adapter = unit->port->adapter;
	int retval;
	int status;
	struct zfcp_fsf_req *fsf_req;

	/* issue task management function */
	fsf_req = zfcp_fsf_send_fcp_command_task_management
		(adapter, unit, tm_flags, 0);
	if (!fsf_req) {
		ZFCP_LOG_INFO("error: creation of task management request "
			      "failed for unit 0x%016Lx on port 0x%016Lx on  "
			      "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
			      zfcp_get_busid_by_adapter(adapter));
		retval = -ENOMEM;
		goto out;
	}

	retval = zfcp_fsf_req_wait_and_cleanup(fsf_req,
					       ZFCP_UNINTERRUPTIBLE, &status);
	/*
	 * check completion status of task management function
	 * (status should always be valid since no signals permitted)
	 */
	if (status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED)
		retval = -EIO;
	else if (status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP)
		retval = -ENOTSUPP;
	else
		retval = 0;
 out:
	return retval;
}

/*
 * function:	zfcp_scsi_eh_bus_reset_handler
 *
 * purpose:
 *
 * returns:
 */
int
zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
{
	int retval = 0;
	struct zfcp_unit *unit;
	struct Scsi_Host *scsi_host = scpnt->device->host;

	spin_unlock_irq(scsi_host->host_lock);

	unit = (struct zfcp_unit *) scpnt->device->hostdata;
	ZFCP_LOG_NORMAL("bus reset because of problems with "
			"unit 0x%016Lx\n", unit->fcp_lun);
	zfcp_erp_adapter_reopen(unit->port->adapter, 0);
	zfcp_erp_wait(unit->port->adapter);
	retval = SUCCESS;

	spin_lock_irq(scsi_host->host_lock);
	return retval;
}

/*
 * function:	zfcp_scsi_eh_host_reset_handler
 *
 * purpose:
 *
 * returns:
 */
int
zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
{
	int retval = 0;
	struct zfcp_unit *unit;
	struct Scsi_Host *scsi_host = scpnt->device->host;

	spin_unlock_irq(scsi_host->host_lock);

	unit = (struct zfcp_unit *) scpnt->device->hostdata;
	ZFCP_LOG_NORMAL("host reset because of problems with "
			"unit 0x%016Lx\n", unit->fcp_lun);
	zfcp_erp_adapter_reopen(unit->port->adapter, 0);
	zfcp_erp_wait(unit->port->adapter);
	retval = SUCCESS;

	spin_lock_irq(scsi_host->host_lock);
	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
int
zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
{
	int retval = 0;
	static unsigned int unique_id = 0;

	/* register adapter as SCSI host with mid layer of SCSI stack */
	adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
					     sizeof (struct zfcp_adapter *));
	if (!adapter->scsi_host) {
		ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
				"for adapter %s ",
				zfcp_get_busid_by_adapter(adapter));
		retval = -EIO;
		goto out;
	}
	ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);

	/* tell the SCSI stack some characteristics of this adapter */
	adapter->scsi_host->max_id = 1;
	adapter->scsi_host->max_lun = 1;
	adapter->scsi_host->max_channel = 0;
	adapter->scsi_host->unique_id = unique_id++;	/* FIXME */
	adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
	adapter->scsi_host->transportt = zfcp_transport_template;
	/*
	 * Reverse mapping of the host number to avoid race condition
	 */
	adapter->scsi_host_no = adapter->scsi_host->host_no;

	/*
	 * save a pointer to our own adapter data structure within
	 * hostdata field of SCSI host data structure
	 */
	adapter->scsi_host->hostdata[0] = (unsigned long) adapter;

	if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
		scsi_host_put(adapter->scsi_host);
		retval = -EIO;
		goto out;
	}
	atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
 out:
	return retval;
}

/*
 * function:	
 *
 * purpose:	
 *
 * returns:
 */
void
zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
{
	struct Scsi_Host *shost;

	shost = adapter->scsi_host;
	if (!shost)
		return;
	scsi_remove_host(shost);
	scsi_host_put(shost);
	adapter->scsi_host = NULL;
	adapter->scsi_host_no = 0;
	atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);

	return;
}


void
zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
{
	adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
	adapter->scsi_er_timer.data = (unsigned long) adapter;
	adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
	add_timer(&adapter->scsi_er_timer);
}

/*
 * Support functions for FC transport class
 */
static void
zfcp_get_port_id(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_port_id(starget) = port->d_id;
	else
		fc_starget_port_id(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

static void
zfcp_get_port_name(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_port_name(starget) = port->wwpn;
	else
		fc_starget_port_name(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

static void
zfcp_get_node_name(struct scsi_target *starget)
{
	struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
	struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
	struct zfcp_port *port;
	unsigned long flags;

	read_lock_irqsave(&zfcp_data.config_lock, flags);
	port = zfcp_port_lookup(adapter, starget->channel, starget->id);
	if (port)
		fc_starget_node_name(starget) = port->wwnn;
	else
		fc_starget_node_name(starget) = -1;
	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
}

struct fc_function_template zfcp_transport_functions = {
	.get_starget_port_id = zfcp_get_port_id,
	.get_starget_port_name = zfcp_get_port_name,
	.get_starget_node_name = zfcp_get_node_name,
	.show_starget_port_id = 1,
	.show_starget_port_name = 1,
	.show_starget_node_name = 1,
};

/**
 * ZFCP_DEFINE_SCSI_ATTR
 * @_name:   name of show attribute
 * @_format: format string
 * @_value:  value to print
 *
 * Generates attribute for a unit.
 */
#define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev,        \
                                              char *buf)                 \
{                                                                        \
        struct scsi_device *sdev;                                        \
        struct zfcp_unit *unit;                                          \
                                                                         \
        sdev = to_scsi_device(dev);                                      \
        unit = sdev->hostdata;                                           \
        return sprintf(buf, _format, _value);                            \
}                                                                        \
                                                                         \
static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);

ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);

static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
	&dev_attr_fcp_lun,
	&dev_attr_wwpn,
	&dev_attr_hba_id,
	NULL
};

#undef ZFCP_LOG_AREA