Pull 5165 into release branch
[sfrench/cifs-2.6.git] / drivers / s390 / scsi / zfcp_scsi.c
1 /* 
2  * 
3  * linux/drivers/s390/scsi/zfcp_scsi.c
4  * 
5  * FCP adapter driver for IBM eServer zSeries 
6  * 
7  * (C) Copyright IBM Corp. 2002, 2004
8  *
9  * Author(s): Martin Peschke <mpeschke@de.ibm.com> 
10  *            Raimund Schroeder <raimund.schroeder@de.ibm.com> 
11  *            Aron Zeh
12  *            Wolfgang Taphorn
13  *            Stefan Bader <stefan.bader@de.ibm.com> 
14  *            Heiko Carstens <heiko.carstens@de.ibm.com> 
15  *            Andreas Herrmann <aherrman@de.ibm.com>
16  * 
17  * This program is free software; you can redistribute it and/or modify 
18  * it under the terms of the GNU General Public License as published by 
19  * the Free Software Foundation; either version 2, or (at your option) 
20  * any later version. 
21  * 
22  * This program is distributed in the hope that it will be useful, 
23  * but WITHOUT ANY WARRANTY; without even the implied warranty of 
24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
25  * GNU General Public License for more details. 
26  * 
27  * You should have received a copy of the GNU General Public License 
28  * along with this program; if not, write to the Free Software 
29  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 
30  */
31
32 #define ZFCP_LOG_AREA                   ZFCP_LOG_AREA_SCSI
33
34 #define ZFCP_SCSI_REVISION "$Revision: 1.74 $"
35
36 #include "zfcp_ext.h"
37
38 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
39 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
40 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
41 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
42                                   void (*done) (struct scsi_cmnd *));
43 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
44 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
45 static int zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *);
46 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
47 static int zfcp_task_management_function(struct zfcp_unit *, u8,
48                                          struct scsi_cmnd *);
49
50 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
51                                           scsi_lun_t);
52 static struct zfcp_port *zfcp_port_lookup(struct zfcp_adapter *, int,
53                                           scsi_id_t);
54
55 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
56
57 struct scsi_transport_template *zfcp_transport_template;
58
59 struct zfcp_data zfcp_data = {
60         .scsi_host_template = {
61               name:                    ZFCP_NAME,
62               proc_name:               "zfcp",
63               proc_info:               NULL,
64               detect:                  NULL,
65               slave_alloc:             zfcp_scsi_slave_alloc,
66               slave_configure:         zfcp_scsi_slave_configure,
67               slave_destroy:           zfcp_scsi_slave_destroy,
68               queuecommand:            zfcp_scsi_queuecommand,
69               eh_abort_handler:        zfcp_scsi_eh_abort_handler,
70               eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
71               eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
72               eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
73                                        /* FIXME(openfcp): Tune */
74               can_queue:               4096,
75               this_id:                 0,
76               /*
77                * FIXME:
78                * one less? can zfcp_create_sbale cope with it?
79                */
80               sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
81               cmd_per_lun:             1,
82               unchecked_isa_dma:       0,
83               use_clustering:          1,
84               sdev_attrs:              zfcp_sysfs_sdev_attrs,
85         },
86         .driver_version = ZFCP_VERSION,
87         /* rest initialised with zeros */
88 };
89
90 /* Find start of Response Information in FCP response unit*/
91 char *
92 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
93 {
94         char *fcp_rsp_info_ptr;
95
96         fcp_rsp_info_ptr =
97             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
98
99         return fcp_rsp_info_ptr;
100 }
101
102 /* Find start of Sense Information in FCP response unit*/
103 char *
104 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
105 {
106         char *fcp_sns_info_ptr;
107
108         fcp_sns_info_ptr =
109             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
110         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
111                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
112                     fcp_rsp_iu->fcp_rsp_len;
113
114         return fcp_sns_info_ptr;
115 }
116
117 fcp_dl_t *
118 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
119 {
120         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
121         fcp_dl_t *fcp_dl_addr;
122
123         fcp_dl_addr = (fcp_dl_t *)
124                 ((unsigned char *) fcp_cmd +
125                  sizeof (struct fcp_cmnd_iu) + additional_length);
126         /*
127          * fcp_dl_addr = start address of fcp_cmnd structure + 
128          * size of fixed part + size of dynamically sized add_dcp_cdb field
129          * SEE FCP-2 documentation
130          */
131         return fcp_dl_addr;
132 }
133
134 fcp_dl_t
135 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
136 {
137         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
138 }
139
140 void
141 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
142 {
143         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
144 }
145
146 /*
147  * note: it's a bit-or operation not an assignment
148  * regarding the specified byte
149  */
150 static inline void
151 set_byte(u32 * result, char status, char pos)
152 {
153         *result |= status << (pos * 8);
154 }
155
156 void
157 set_host_byte(u32 * result, char status)
158 {
159         set_byte(result, status, 2);
160 }
161
162 void
163 set_driver_byte(u32 * result, char status)
164 {
165         set_byte(result, status, 3);
166 }
167
168 /*
169  * function:    zfcp_scsi_slave_alloc
170  *
171  * purpose:
172  *
173  * returns:
174  */
175
176 static int
177 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
178 {
179         struct zfcp_adapter *adapter;
180         struct zfcp_unit *unit;
181         unsigned long flags;
182         int retval = -ENXIO;
183
184         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
185         if (!adapter)
186                 goto out;
187
188         read_lock_irqsave(&zfcp_data.config_lock, flags);
189         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
190         if (unit) {
191                 sdp->hostdata = unit;
192                 unit->device = sdp;
193                 zfcp_unit_get(unit);
194                 retval = 0;
195         }
196         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
197  out:
198         return retval;
199 }
200
201 /*
202  * function:    zfcp_scsi_slave_destroy
203  *
204  * purpose:
205  *
206  * returns:
207  */
208
209 static void
210 zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
211 {
212         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
213
214         if (unit) {
215                 sdpnt->hostdata = NULL;
216                 unit->device = NULL;
217                 zfcp_unit_put(unit);
218         } else {
219                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
220                                 "address %p\n", sdpnt);
221         }
222 }
223
224 /* 
225  * called from scsi midlayer to allow finetuning of a device.
226  */
227 static int
228 zfcp_scsi_slave_configure(struct scsi_device *sdp)
229 {
230         if (sdp->tagged_supported)
231                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
232         else
233                 scsi_adjust_queue_depth(sdp, 0, 1);
234         return 0;
235 }
236
237 /**
238  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
239  * @scpnt: pointer to struct scsi_cmnd where result is set
240  * @result: result to be set in scpnt (e.g. DID_ERROR)
241  */
242 static void
243 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
244 {
245         set_host_byte(&scpnt->result, result);
246         if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
247                 zfcp_scsi_dbf_event_result("fail", 4,
248                         (struct zfcp_adapter*) scpnt->device->host->hostdata[0],
249                         scpnt);
250         /* return directly */
251         scpnt->scsi_done(scpnt);
252 }
253
254 /**
255  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
256  *      zfcp_scsi_command_sync
257  * @adapter: adapter where scsi command is issued
258  * @unit: unit to which scsi command is sent
259  * @scpnt: scsi command to be sent
260  * @timer: timer to be started if request is successfully initiated
261  *
262  * Note: In scsi_done function must be set in scpnt.
263  */
264 int
265 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
266                         struct scsi_cmnd *scpnt, struct timer_list *timer)
267 {
268         int tmp;
269         int retval;
270
271         retval = 0;
272
273         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
274         BUG_ON(scpnt->scsi_done == NULL);
275
276         if (unlikely(NULL == unit)) {
277                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
278                 goto out;
279         }
280
281         if (unlikely(
282               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
283              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
284                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
285                                "0x%016Lx on adapter %s\n",
286                                unit->fcp_lun, unit->port->wwpn,
287                                zfcp_get_busid_by_adapter(adapter));
288                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
289                 goto out;
290         }
291
292         if (unlikely(
293              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
294                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
295                                "on port 0x%016Lx in recovery\n",
296                                zfcp_get_busid_by_unit(unit),
297                                unit->fcp_lun, unit->port->wwpn);
298                 retval = SCSI_MLQUEUE_DEVICE_BUSY;
299                 goto out;
300         }
301
302         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, timer,
303                                              ZFCP_REQ_AUTO_CLEANUP);
304
305         if (unlikely(tmp < 0)) {
306                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
307                 retval = SCSI_MLQUEUE_HOST_BUSY;
308         }
309
310 out:
311         return retval;
312 }
313
314 void
315 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
316 {
317         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
318         complete(wait);
319 }
320
321
322 /**
323  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
324  * @unit: unit where command is sent to
325  * @scpnt: scsi command to be sent
326  * @timer: timer to be started if request is successfully initiated
327  * Return: 0
328  *
329  * Errors are indicated in scpnt->result
330  */
331 int
332 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
333                        struct timer_list *timer)
334 {
335         int ret;
336         DECLARE_COMPLETION(wait);
337
338         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
339         scpnt->scsi_done = zfcp_scsi_command_sync_handler;
340         ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt, timer);
341         if (ret == 0)
342                 wait_for_completion(&wait);
343
344         scpnt->SCp.ptr = NULL;
345
346         return 0;
347 }
348
349 /*
350  * function:    zfcp_scsi_queuecommand
351  *
352  * purpose:     enqueues a SCSI command to the specified target device
353  *
354  * returns:     0 - success, SCSI command enqueued
355  *              !0 - failure
356  */
357 int
358 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
359                        void (*done) (struct scsi_cmnd *))
360 {
361         struct zfcp_unit *unit;
362         struct zfcp_adapter *adapter;
363
364         /* reset the status for this request */
365         scpnt->result = 0;
366         scpnt->host_scribble = NULL;
367         scpnt->scsi_done = done;
368
369         /*
370          * figure out adapter and target device
371          * (stored there by zfcp_scsi_slave_alloc)
372          */
373         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
374         unit = (struct zfcp_unit *) scpnt->device->hostdata;
375
376         return zfcp_scsi_command_async(adapter, unit, scpnt, NULL);
377 }
378
379 /*
380  * function:    zfcp_unit_lookup
381  *
382  * purpose:
383  *
384  * returns:
385  *
386  * context:     
387  */
388 static struct zfcp_unit *
389 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
390                  scsi_lun_t lun)
391 {
392         struct zfcp_port *port;
393         struct zfcp_unit *unit, *retval = NULL;
394
395         list_for_each_entry(port, &adapter->port_list_head, list) {
396                 if (!port->rport || (id != port->rport->scsi_target_id))
397                         continue;
398                 list_for_each_entry(unit, &port->unit_list_head, list) {
399                         if (lun == unit->scsi_lun) {
400                                 retval = unit;
401                                 goto out;
402                         }
403                 }
404         }
405  out:
406         return retval;
407 }
408
409 static struct zfcp_port *
410 zfcp_port_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id)
411 {
412         struct zfcp_port *port;
413
414         list_for_each_entry(port, &adapter->port_list_head, list) {
415                 if (port->rport && (id == port->rport->scsi_target_id))
416                         return port;
417         }
418         return (struct zfcp_port *) NULL;
419 }
420
421 /**
422  * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
423  * @scpnt: pointer to scsi_cmnd to be aborted 
424  * Return: SUCCESS - command has been aborted and cleaned up in internal
425  *          bookkeeping, SCSI stack won't be called for aborted command
426  *         FAILED - otherwise
427  *
428  * We do not need to care for a SCSI command which completes normally
429  * but late during this abort routine runs.  We are allowed to return
430  * late commands to the SCSI stack.  It tracks the state of commands and
431  * will handle late commands.  (Usually, the normal completion of late
432  * commands is ignored with respect to the running abort operation.)
433  */
434 int
435 zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
436 {
437         struct Scsi_Host *scsi_host;
438         struct zfcp_adapter *adapter;
439         struct zfcp_unit *unit;
440         int retval = SUCCESS;
441         struct zfcp_fsf_req *new_fsf_req = NULL;
442         struct zfcp_fsf_req *old_fsf_req;
443         unsigned long flags;
444
445         scsi_host = scpnt->device->host;
446         adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
447         unit = (struct zfcp_unit *) scpnt->device->hostdata;
448
449         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
450                       scpnt, zfcp_get_busid_by_adapter(adapter));
451
452         /* avoid race condition between late normal completion and abort */
453         write_lock_irqsave(&adapter->abort_lock, flags);
454
455         /*
456          * Check whether command has just completed and can not be aborted.
457          * Even if the command has just been completed late, we can access
458          * scpnt since the SCSI stack does not release it at least until
459          * this routine returns. (scpnt is parameter passed to this routine
460          * and must not disappear during abort even on late completion.)
461          */
462         old_fsf_req = (struct zfcp_fsf_req *) scpnt->host_scribble;
463         if (!old_fsf_req) {
464                 write_unlock_irqrestore(&adapter->abort_lock, flags);
465                 zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, new_fsf_req);
466                 retval = SUCCESS;
467                 goto out;
468         }
469         old_fsf_req->data = 0;
470         old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
471
472         /* don't access old_fsf_req after releasing the abort_lock */
473         write_unlock_irqrestore(&adapter->abort_lock, flags);
474         /* call FSF routine which does the abort */
475         new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
476                                                  adapter, unit, 0);
477         if (!new_fsf_req) {
478                 ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
479                 retval = FAILED;
480                 goto out;
481         }
482
483         /* wait for completion of abort */
484         __wait_event(new_fsf_req->completion_wq,
485                      new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
486
487         /* status should be valid since signals were not permitted */
488         if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
489                 zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, new_fsf_req);
490                 retval = SUCCESS;
491         } else if (new_fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
492                 zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, new_fsf_req);
493                 retval = SUCCESS;
494         } else {
495                 zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, new_fsf_req);
496                 retval = FAILED;
497         }
498         zfcp_fsf_req_free(new_fsf_req);
499  out:
500         return retval;
501 }
502
503 /*
504  * function:    zfcp_scsi_eh_device_reset_handler
505  *
506  * purpose:
507  *
508  * returns:
509  */
510 int
511 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
512 {
513         int retval;
514         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
515
516         if (!unit) {
517                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
518                 retval = SUCCESS;
519                 goto out;
520         }
521         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
522
523         /*
524          * If we do not know whether the unit supports 'logical unit reset'
525          * then try 'logical unit reset' and proceed with 'target reset'
526          * if 'logical unit reset' fails.
527          * If the unit is known not to support 'logical unit reset' then
528          * skip 'logical unit reset' and try 'target reset' immediately.
529          */
530         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
531                               &unit->status)) {
532                 retval = zfcp_task_management_function(unit,
533                                                        FCP_LOGICAL_UNIT_RESET,
534                                                        scpnt);
535                 if (retval) {
536                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
537                         if (retval == -ENOTSUPP)
538                                 atomic_set_mask
539                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
540                                      &unit->status);
541                         /* fall through and try 'target reset' next */
542                 } else {
543                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
544                                        unit);
545                         /* avoid 'target reset' */
546                         retval = SUCCESS;
547                         goto out;
548                 }
549         }
550         retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
551         if (retval) {
552                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
553                 retval = FAILED;
554         } else {
555                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
556                 retval = SUCCESS;
557         }
558  out:
559         return retval;
560 }
561
562 static int
563 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
564                               struct scsi_cmnd *scpnt)
565 {
566         struct zfcp_adapter *adapter = unit->port->adapter;
567         struct zfcp_fsf_req *fsf_req;
568         int retval = 0;
569
570         /* issue task management function */
571         fsf_req = zfcp_fsf_send_fcp_command_task_management
572                 (adapter, unit, tm_flags, 0);
573         if (!fsf_req) {
574                 ZFCP_LOG_INFO("error: creation of task management request "
575                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
576                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
577                               zfcp_get_busid_by_adapter(adapter));
578                 zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
579                 retval = -ENOMEM;
580                 goto out;
581         }
582
583         __wait_event(fsf_req->completion_wq,
584                      fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
585
586         /*
587          * check completion status of task management function
588          */
589         if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
590                 zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
591                 retval = -EIO;
592         } else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
593                 zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
594                 retval = -ENOTSUPP;
595         } else
596                 zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);
597
598         zfcp_fsf_req_free(fsf_req);
599  out:
600         return retval;
601 }
602
603 /**
604  * zfcp_scsi_eh_bus_reset_handler - reset bus (reopen adapter)
605  */
606 int
607 zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
608 {
609         struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
610         struct zfcp_adapter *adapter = unit->port->adapter;
611
612         ZFCP_LOG_NORMAL("bus reset because of problems with "
613                         "unit 0x%016Lx\n", unit->fcp_lun);
614         zfcp_erp_adapter_reopen(adapter, 0);
615         zfcp_erp_wait(adapter);
616
617         return SUCCESS;
618 }
619
620 /**
621  * zfcp_scsi_eh_host_reset_handler - reset host (reopen adapter)
622  */
623 int
624 zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
625 {
626         struct zfcp_unit *unit = (struct zfcp_unit*) scpnt->device->hostdata;
627         struct zfcp_adapter *adapter = unit->port->adapter;
628
629         ZFCP_LOG_NORMAL("host reset because of problems with "
630                         "unit 0x%016Lx\n", unit->fcp_lun);
631         zfcp_erp_adapter_reopen(adapter, 0);
632         zfcp_erp_wait(adapter);
633
634         return SUCCESS;
635 }
636
637 /*
638  * function:    
639  *
640  * purpose:     
641  *
642  * returns:
643  */
644 int
645 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
646 {
647         int retval = 0;
648         static unsigned int unique_id = 0;
649
650         /* register adapter as SCSI host with mid layer of SCSI stack */
651         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
652                                              sizeof (struct zfcp_adapter *));
653         if (!adapter->scsi_host) {
654                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
655                                 "for adapter %s ",
656                                 zfcp_get_busid_by_adapter(adapter));
657                 retval = -EIO;
658                 goto out;
659         }
660         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
661
662         /* tell the SCSI stack some characteristics of this adapter */
663         adapter->scsi_host->max_id = 1;
664         adapter->scsi_host->max_lun = 1;
665         adapter->scsi_host->max_channel = 0;
666         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
667         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
668         adapter->scsi_host->transportt = zfcp_transport_template;
669         /*
670          * Reverse mapping of the host number to avoid race condition
671          */
672         adapter->scsi_host_no = adapter->scsi_host->host_no;
673
674         /*
675          * save a pointer to our own adapter data structure within
676          * hostdata field of SCSI host data structure
677          */
678         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
679
680         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
681                 scsi_host_put(adapter->scsi_host);
682                 retval = -EIO;
683                 goto out;
684         }
685         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
686  out:
687         return retval;
688 }
689
690 /*
691  * function:    
692  *
693  * purpose:     
694  *
695  * returns:
696  */
697 void
698 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
699 {
700         struct Scsi_Host *shost;
701         struct zfcp_port *port;
702
703         shost = adapter->scsi_host;
704         if (!shost)
705                 return;
706         read_lock_irq(&zfcp_data.config_lock);
707         list_for_each_entry(port, &adapter->port_list_head, list)
708                 if (port->rport)
709                         port->rport = NULL;
710         read_unlock_irq(&zfcp_data.config_lock);
711         fc_remove_host(shost);
712         scsi_remove_host(shost);
713         scsi_host_put(shost);
714         adapter->scsi_host = NULL;
715         adapter->scsi_host_no = 0;
716         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
717
718         return;
719 }
720
721
722 void
723 zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
724 {
725         adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
726         adapter->scsi_er_timer.data = (unsigned long) adapter;
727         adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
728         add_timer(&adapter->scsi_er_timer);
729 }
730
731 /*
732  * Support functions for FC transport class
733  */
734 static void
735 zfcp_get_port_id(struct scsi_target *starget)
736 {
737         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
738         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
739         struct zfcp_port *port;
740         unsigned long flags;
741
742         read_lock_irqsave(&zfcp_data.config_lock, flags);
743         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
744         if (port)
745                 fc_starget_port_id(starget) = port->d_id;
746         else
747                 fc_starget_port_id(starget) = -1;
748         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
749 }
750
751 static void
752 zfcp_get_port_name(struct scsi_target *starget)
753 {
754         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
755         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
756         struct zfcp_port *port;
757         unsigned long flags;
758
759         read_lock_irqsave(&zfcp_data.config_lock, flags);
760         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
761         if (port)
762                 fc_starget_port_name(starget) = port->wwpn;
763         else
764                 fc_starget_port_name(starget) = -1;
765         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
766 }
767
768 static void
769 zfcp_get_node_name(struct scsi_target *starget)
770 {
771         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
772         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
773         struct zfcp_port *port;
774         unsigned long flags;
775
776         read_lock_irqsave(&zfcp_data.config_lock, flags);
777         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
778         if (port)
779                 fc_starget_node_name(starget) = port->wwnn;
780         else
781                 fc_starget_node_name(starget) = -1;
782         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
783 }
784
785 struct fc_function_template zfcp_transport_functions = {
786         .get_starget_port_id = zfcp_get_port_id,
787         .get_starget_port_name = zfcp_get_port_name,
788         .get_starget_node_name = zfcp_get_node_name,
789         .show_starget_port_id = 1,
790         .show_starget_port_name = 1,
791         .show_starget_node_name = 1,
792         .show_rport_supported_classes = 1,
793         .show_host_node_name = 1,
794         .show_host_port_name = 1,
795         .show_host_supported_classes = 1,
796         .show_host_maxframe_size = 1,
797         .show_host_serial_number = 1,
798         .show_host_speed = 1,
799         .show_host_port_id = 1,
800 };
801
802 /**
803  * ZFCP_DEFINE_SCSI_ATTR
804  * @_name:   name of show attribute
805  * @_format: format string
806  * @_value:  value to print
807  *
808  * Generates attribute for a unit.
809  */
810 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
811 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
812                                               char *buf)                 \
813 {                                                                        \
814         struct scsi_device *sdev;                                        \
815         struct zfcp_unit *unit;                                          \
816                                                                          \
817         sdev = to_scsi_device(dev);                                      \
818         unit = sdev->hostdata;                                           \
819         return sprintf(buf, _format, _value);                            \
820 }                                                                        \
821                                                                          \
822 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
823
824 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
825 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
826 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
827
828 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
829         &dev_attr_fcp_lun,
830         &dev_attr_wwpn,
831         &dev_attr_hba_id,
832         NULL
833 };
834
835 #undef ZFCP_LOG_AREA