6965992ddbbf73e7da5b0eeadc4509c0bc694822
[linux-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
49 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int, scsi_id_t,
50                                           scsi_lun_t);
51 static struct zfcp_port *zfcp_port_lookup(struct zfcp_adapter *, int,
52                                           scsi_id_t);
53
54 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
55
56 struct scsi_transport_template *zfcp_transport_template;
57
58 struct zfcp_data zfcp_data = {
59         .scsi_host_template = {
60               name:                    ZFCP_NAME,
61               proc_name:               "zfcp",
62               proc_info:               NULL,
63               detect:                  NULL,
64               slave_alloc:             zfcp_scsi_slave_alloc,
65               slave_configure:         zfcp_scsi_slave_configure,
66               slave_destroy:           zfcp_scsi_slave_destroy,
67               queuecommand:            zfcp_scsi_queuecommand,
68               eh_abort_handler:        zfcp_scsi_eh_abort_handler,
69               eh_device_reset_handler: zfcp_scsi_eh_device_reset_handler,
70               eh_bus_reset_handler:    zfcp_scsi_eh_bus_reset_handler,
71               eh_host_reset_handler:   zfcp_scsi_eh_host_reset_handler,
72                                        /* FIXME(openfcp): Tune */
73               can_queue:               4096,
74               this_id:                 0,
75               /*
76                * FIXME:
77                * one less? can zfcp_create_sbale cope with it?
78                */
79               sg_tablesize:            ZFCP_MAX_SBALES_PER_REQ,
80               cmd_per_lun:             1,
81               unchecked_isa_dma:       0,
82               use_clustering:          1,
83               sdev_attrs:              zfcp_sysfs_sdev_attrs,
84         },
85         .driver_version = ZFCP_VERSION,
86         /* rest initialised with zeros */
87 };
88
89 /* Find start of Response Information in FCP response unit*/
90 char *
91 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
92 {
93         char *fcp_rsp_info_ptr;
94
95         fcp_rsp_info_ptr =
96             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
97
98         return fcp_rsp_info_ptr;
99 }
100
101 /* Find start of Sense Information in FCP response unit*/
102 char *
103 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
104 {
105         char *fcp_sns_info_ptr;
106
107         fcp_sns_info_ptr =
108             (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
109         if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
110                 fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
111                     fcp_rsp_iu->fcp_rsp_len;
112
113         return fcp_sns_info_ptr;
114 }
115
116 fcp_dl_t *
117 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
118 {
119         int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
120         fcp_dl_t *fcp_dl_addr;
121
122         fcp_dl_addr = (fcp_dl_t *)
123                 ((unsigned char *) fcp_cmd +
124                  sizeof (struct fcp_cmnd_iu) + additional_length);
125         /*
126          * fcp_dl_addr = start address of fcp_cmnd structure + 
127          * size of fixed part + size of dynamically sized add_dcp_cdb field
128          * SEE FCP-2 documentation
129          */
130         return fcp_dl_addr;
131 }
132
133 fcp_dl_t
134 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
135 {
136         return *zfcp_get_fcp_dl_ptr(fcp_cmd);
137 }
138
139 void
140 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
141 {
142         *zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
143 }
144
145 /*
146  * note: it's a bit-or operation not an assignment
147  * regarding the specified byte
148  */
149 static inline void
150 set_byte(u32 * result, char status, char pos)
151 {
152         *result |= status << (pos * 8);
153 }
154
155 void
156 set_host_byte(u32 * result, char status)
157 {
158         set_byte(result, status, 2);
159 }
160
161 void
162 set_driver_byte(u32 * result, char status)
163 {
164         set_byte(result, status, 3);
165 }
166
167 /*
168  * function:    zfcp_scsi_slave_alloc
169  *
170  * purpose:
171  *
172  * returns:
173  */
174
175 static int
176 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
177 {
178         struct zfcp_adapter *adapter;
179         struct zfcp_unit *unit;
180         unsigned long flags;
181         int retval = -ENODEV;
182
183         adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
184         if (!adapter)
185                 goto out;
186
187         read_lock_irqsave(&zfcp_data.config_lock, flags);
188         unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
189         if (unit) {
190                 sdp->hostdata = unit;
191                 unit->device = sdp;
192                 zfcp_unit_get(unit);
193                 retval = 0;
194         }
195         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
196  out:
197         return retval;
198 }
199
200 /*
201  * function:    zfcp_scsi_slave_destroy
202  *
203  * purpose:
204  *
205  * returns:
206  */
207
208 static void
209 zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
210 {
211         struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
212
213         if (unit) {
214                 sdpnt->hostdata = NULL;
215                 unit->device = NULL;
216                 zfcp_unit_put(unit);
217         } else {
218                 ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
219                                 "address %p\n", sdpnt);
220         }
221 }
222
223 /* 
224  * called from scsi midlayer to allow finetuning of a device.
225  */
226 static int
227 zfcp_scsi_slave_configure(struct scsi_device *sdp)
228 {
229         if (sdp->tagged_supported)
230                 scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
231         else
232                 scsi_adjust_queue_depth(sdp, 0, 1);
233         return 0;
234 }
235
236 /**
237  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
238  * @scpnt: pointer to struct scsi_cmnd where result is set
239  * @result: result to be set in scpnt (e.g. DID_ERROR)
240  */
241 static void
242 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
243 {
244         set_host_byte(&scpnt->result, result);
245         zfcp_cmd_dbf_event_scsi("failing", scpnt);
246         /* return directly */
247         scpnt->scsi_done(scpnt);
248 }
249
250 /**
251  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
252  *      zfcp_scsi_command_sync
253  * @adapter: adapter where scsi command is issued
254  * @unit: unit to which scsi command is sent
255  * @scpnt: scsi command to be sent
256  * @timer: timer to be started if request is successfully initiated
257  *
258  * Note: In scsi_done function must be set in scpnt.
259  */
260 int
261 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
262                         struct scsi_cmnd *scpnt, struct timer_list *timer)
263 {
264         int tmp;
265         int retval;
266
267         retval = 0;
268
269         BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
270         BUG_ON(scpnt->scsi_done == NULL);
271
272         if (unlikely(NULL == unit)) {
273                 zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
274                 goto out;
275         }
276
277         if (unlikely(
278               atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
279              !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
280                 ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
281                                "0x%016Lx on adapter %s\n",
282                                unit->fcp_lun, unit->port->wwpn,
283                                zfcp_get_busid_by_adapter(adapter));
284                 zfcp_scsi_command_fail(scpnt, DID_ERROR);
285                 goto out;
286         }
287
288         if (unlikely(
289              !atomic_test_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))) {
290                 ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
291                                "on port 0x%016Lx in recovery\n",
292                                zfcp_get_busid_by_unit(unit),
293                                unit->fcp_lun, unit->port->wwpn);
294                 retval = SCSI_MLQUEUE_DEVICE_BUSY;
295                 goto out;
296         }
297
298         tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, timer,
299                                              ZFCP_REQ_AUTO_CLEANUP);
300
301         if (unlikely(tmp < 0)) {
302                 ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
303                 retval = SCSI_MLQUEUE_HOST_BUSY;
304         }
305
306 out:
307         return retval;
308 }
309
310 void
311 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
312 {
313         struct completion *wait = (struct completion *) scpnt->SCp.ptr;
314         complete(wait);
315 }
316
317
318 /**
319  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
320  * @unit: unit where command is sent to
321  * @scpnt: scsi command to be sent
322  * @timer: timer to be started if request is successfully initiated
323  * Return: 0
324  *
325  * Errors are indicated in scpnt->result
326  */
327 int
328 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
329                        struct timer_list *timer)
330 {
331         int ret;
332         DECLARE_COMPLETION(wait);
333
334         scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
335         scpnt->scsi_done = zfcp_scsi_command_sync_handler;
336         ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt, timer);
337         if (ret == 0)
338                 wait_for_completion(&wait);
339
340         scpnt->SCp.ptr = NULL;
341
342         return 0;
343 }
344
345 /*
346  * function:    zfcp_scsi_queuecommand
347  *
348  * purpose:     enqueues a SCSI command to the specified target device
349  *
350  * returns:     0 - success, SCSI command enqueued
351  *              !0 - failure
352  */
353 int
354 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
355                        void (*done) (struct scsi_cmnd *))
356 {
357         struct zfcp_unit *unit;
358         struct zfcp_adapter *adapter;
359
360         /* reset the status for this request */
361         scpnt->result = 0;
362         scpnt->host_scribble = NULL;
363         scpnt->scsi_done = done;
364
365         /*
366          * figure out adapter and target device
367          * (stored there by zfcp_scsi_slave_alloc)
368          */
369         adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
370         unit = (struct zfcp_unit *) scpnt->device->hostdata;
371
372         return zfcp_scsi_command_async(adapter, unit, scpnt, NULL);
373 }
374
375 /*
376  * function:    zfcp_unit_lookup
377  *
378  * purpose:
379  *
380  * returns:
381  *
382  * context:     
383  */
384 static struct zfcp_unit *
385 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id,
386                  scsi_lun_t lun)
387 {
388         struct zfcp_port *port;
389         struct zfcp_unit *unit, *retval = NULL;
390
391         list_for_each_entry(port, &adapter->port_list_head, list) {
392                 if (id != port->scsi_id)
393                         continue;
394                 list_for_each_entry(unit, &port->unit_list_head, list) {
395                         if (lun == unit->scsi_lun) {
396                                 retval = unit;
397                                 goto out;
398                         }
399                 }
400         }
401  out:
402         return retval;
403 }
404
405 static struct zfcp_port *
406 zfcp_port_lookup(struct zfcp_adapter *adapter, int channel, scsi_id_t id)
407 {
408         struct zfcp_port *port;
409
410         list_for_each_entry(port, &adapter->port_list_head, list) {
411                 if (id == port->scsi_id)
412                         return port;
413         }
414         return (struct zfcp_port *) NULL;
415 }
416
417 /*
418  * function:    zfcp_scsi_eh_abort_handler
419  *
420  * purpose:     tries to abort the specified (timed out) SCSI command
421  *
422  * note:        We do not need to care for a SCSI command which completes
423  *              normally but late during this abort routine runs.
424  *              We are allowed to return late commands to the SCSI stack.
425  *              It tracks the state of commands and will handle late commands.
426  *              (Usually, the normal completion of late commands is ignored with
427  *              respect to the running abort operation. Grep for 'done_late'
428  *              in the SCSI stacks sources.)
429  *
430  * returns:     SUCCESS - command has been aborted and cleaned up in internal
431  *                        bookkeeping,
432  *                        SCSI stack won't be called for aborted command
433  *              FAILED  - otherwise
434  */
435 int
436 __zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
437 {
438         int retval = SUCCESS;
439         struct zfcp_fsf_req *new_fsf_req, *old_fsf_req;
440         struct zfcp_adapter *adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
441         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
442         struct zfcp_port *port = unit->port;
443         struct Scsi_Host *scsi_host = scpnt->device->host;
444         union zfcp_req_data *req_data = NULL;
445         unsigned long flags;
446         u32 status = 0;
447
448         /* the components of a abort_dbf record (fixed size record) */
449         u64 dbf_scsi_cmnd = (unsigned long) scpnt;
450         char dbf_opcode[ZFCP_ABORT_DBF_LENGTH];
451         wwn_t dbf_wwn = port->wwpn;
452         fcp_lun_t dbf_fcp_lun = unit->fcp_lun;
453         u64 dbf_retries = scpnt->retries;
454         u64 dbf_allowed = scpnt->allowed;
455         u64 dbf_timeout = 0;
456         u64 dbf_fsf_req = 0;
457         u64 dbf_fsf_status = 0;
458         u64 dbf_fsf_qual[2] = { 0, 0 };
459         char dbf_result[ZFCP_ABORT_DBF_LENGTH] = "##undef";
460
461         memset(dbf_opcode, 0, ZFCP_ABORT_DBF_LENGTH);
462         memcpy(dbf_opcode,
463                scpnt->cmnd,
464                min(scpnt->cmd_len, (unsigned char) ZFCP_ABORT_DBF_LENGTH));
465
466         ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
467                       scpnt, zfcp_get_busid_by_adapter(adapter));
468
469         spin_unlock_irq(scsi_host->host_lock);
470
471         /*
472          * Race condition between normal (late) completion and abort has
473          * to be avoided.
474          * The entirity of all accesses to scsi_req have to be atomic.
475          * scsi_req is usually part of the fsf_req and thus we block the
476          * release of fsf_req as long as we need to access scsi_req.
477          */
478         write_lock_irqsave(&adapter->abort_lock, flags);
479
480         /*
481          * Check whether command has just completed and can not be aborted.
482          * Even if the command has just been completed late, we can access
483          * scpnt since the SCSI stack does not release it at least until
484          * this routine returns. (scpnt is parameter passed to this routine
485          * and must not disappear during abort even on late completion.)
486          */
487         req_data = (union zfcp_req_data *) scpnt->host_scribble;
488         /* DEBUG */
489         ZFCP_LOG_DEBUG("req_data=%p\n", req_data);
490         if (!req_data) {
491                 ZFCP_LOG_DEBUG("late command completion overtook abort\n");
492                 /*
493                  * That's it.
494                  * Do not initiate abort but return SUCCESS.
495                  */
496                 write_unlock_irqrestore(&adapter->abort_lock, flags);
497                 retval = SUCCESS;
498                 strncpy(dbf_result, "##late1", ZFCP_ABORT_DBF_LENGTH);
499                 goto out;
500         }
501
502         /* Figure out which fsf_req needs to be aborted. */
503         old_fsf_req = req_data->send_fcp_command_task.fsf_req;
504
505         dbf_fsf_req = (unsigned long) old_fsf_req;
506         dbf_timeout =
507             (jiffies - req_data->send_fcp_command_task.start_jiffies) / HZ;
508
509         ZFCP_LOG_DEBUG("old_fsf_req=%p\n", old_fsf_req);
510         if (!old_fsf_req) {
511                 write_unlock_irqrestore(&adapter->abort_lock, flags);
512                 ZFCP_LOG_NORMAL("bug: no old fsf request found\n");
513                 ZFCP_LOG_NORMAL("req_data:\n");
514                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
515                               (char *) req_data, sizeof (union zfcp_req_data));
516                 ZFCP_LOG_NORMAL("scsi_cmnd:\n");
517                 ZFCP_HEX_DUMP(ZFCP_LOG_LEVEL_NORMAL,
518                               (char *) scpnt, sizeof (struct scsi_cmnd));
519                 retval = FAILED;
520                 strncpy(dbf_result, "##bug:r", ZFCP_ABORT_DBF_LENGTH);
521                 goto out;
522         }
523         old_fsf_req->data.send_fcp_command_task.scsi_cmnd = NULL;
524         /* mark old request as being aborted */
525         old_fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
526         /*
527          * We have to collect all information (e.g. unit) needed by 
528          * zfcp_fsf_abort_fcp_command before calling that routine
529          * since that routine is not allowed to access
530          * fsf_req which it is going to abort.
531          * This is because of we need to release fsf_req_list_lock
532          * before calling zfcp_fsf_abort_fcp_command.
533          * Since this lock will not be held, fsf_req may complete
534          * late and may be released meanwhile.
535          */
536         ZFCP_LOG_DEBUG("unit 0x%016Lx (%p)\n", unit->fcp_lun, unit);
537
538         /*
539          * We block (call schedule)
540          * That's why we must release the lock and enable the
541          * interrupts before.
542          * On the other hand we do not need the lock anymore since
543          * all critical accesses to scsi_req are done.
544          */
545         write_unlock_irqrestore(&adapter->abort_lock, flags);
546         /* call FSF routine which does the abort */
547         new_fsf_req = zfcp_fsf_abort_fcp_command((unsigned long) old_fsf_req,
548                                                  adapter, unit, 0);
549         ZFCP_LOG_DEBUG("new_fsf_req=%p\n", new_fsf_req);
550         if (!new_fsf_req) {
551                 retval = FAILED;
552                 ZFCP_LOG_NORMAL("error: initiation of Abort FCP Cmnd "
553                                 "failed\n");
554                 strncpy(dbf_result, "##nores", ZFCP_ABORT_DBF_LENGTH);
555                 goto out;
556         }
557
558         /* wait for completion of abort */
559         ZFCP_LOG_DEBUG("waiting for cleanup...\n");
560 #if 1
561         /*
562          * FIXME:
563          * copying zfcp_fsf_req_wait_and_cleanup code is not really nice
564          */
565         __wait_event(new_fsf_req->completion_wq,
566                      new_fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
567         status = new_fsf_req->status;
568         dbf_fsf_status = new_fsf_req->qtcb->header.fsf_status;
569         /*
570          * Ralphs special debug load provides timestamps in the FSF
571          * status qualifier. This might be specified later if being
572          * useful for debugging aborts.
573          */
574         dbf_fsf_qual[0] =
575             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[0];
576         dbf_fsf_qual[1] =
577             *(u64 *) & new_fsf_req->qtcb->header.fsf_status_qual.word[2];
578         zfcp_fsf_req_free(new_fsf_req);
579 #else
580         retval = zfcp_fsf_req_wait_and_cleanup(new_fsf_req,
581                                                ZFCP_UNINTERRUPTIBLE, &status);
582 #endif
583         ZFCP_LOG_DEBUG("Waiting for cleanup complete, status=0x%x\n", status);
584         /* status should be valid since signals were not permitted */
585         if (status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
586                 retval = SUCCESS;
587                 strncpy(dbf_result, "##succ", ZFCP_ABORT_DBF_LENGTH);
588         } else if (status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
589                 retval = SUCCESS;
590                 strncpy(dbf_result, "##late2", ZFCP_ABORT_DBF_LENGTH);
591         } else {
592                 retval = FAILED;
593                 strncpy(dbf_result, "##fail", ZFCP_ABORT_DBF_LENGTH);
594         }
595
596  out:
597         debug_event(adapter->abort_dbf, 1, &dbf_scsi_cmnd, sizeof (u64));
598         debug_event(adapter->abort_dbf, 1, &dbf_opcode, ZFCP_ABORT_DBF_LENGTH);
599         debug_event(adapter->abort_dbf, 1, &dbf_wwn, sizeof (wwn_t));
600         debug_event(adapter->abort_dbf, 1, &dbf_fcp_lun, sizeof (fcp_lun_t));
601         debug_event(adapter->abort_dbf, 1, &dbf_retries, sizeof (u64));
602         debug_event(adapter->abort_dbf, 1, &dbf_allowed, sizeof (u64));
603         debug_event(adapter->abort_dbf, 1, &dbf_timeout, sizeof (u64));
604         debug_event(adapter->abort_dbf, 1, &dbf_fsf_req, sizeof (u64));
605         debug_event(adapter->abort_dbf, 1, &dbf_fsf_status, sizeof (u64));
606         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[0], sizeof (u64));
607         debug_event(adapter->abort_dbf, 1, &dbf_fsf_qual[1], sizeof (u64));
608         debug_text_event(adapter->abort_dbf, 1, dbf_result);
609
610         spin_lock_irq(scsi_host->host_lock);
611         return retval;
612 }
613
614 int
615 zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
616 {
617         int rc;
618         struct Scsi_Host *scsi_host = scpnt->device->host;
619         spin_lock_irq(scsi_host->host_lock);
620         rc = __zfcp_scsi_eh_abort_handler(scpnt);
621         spin_unlock_irq(scsi_host->host_lock);
622         return rc;
623 }
624
625 /*
626  * function:    zfcp_scsi_eh_device_reset_handler
627  *
628  * purpose:
629  *
630  * returns:
631  */
632 int
633 zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
634 {
635         int retval;
636         struct zfcp_unit *unit = (struct zfcp_unit *) scpnt->device->hostdata;
637         struct Scsi_Host *scsi_host = scpnt->device->host;
638
639         if (!unit) {
640                 ZFCP_LOG_NORMAL("bug: Tried reset for nonexistent unit\n");
641                 retval = SUCCESS;
642                 goto out;
643         }
644         ZFCP_LOG_NORMAL("resetting unit 0x%016Lx\n", unit->fcp_lun);
645
646         /*
647          * If we do not know whether the unit supports 'logical unit reset'
648          * then try 'logical unit reset' and proceed with 'target reset'
649          * if 'logical unit reset' fails.
650          * If the unit is known not to support 'logical unit reset' then
651          * skip 'logical unit reset' and try 'target reset' immediately.
652          */
653         if (!atomic_test_mask(ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
654                               &unit->status)) {
655                 retval =
656                     zfcp_task_management_function(unit, FCP_LOGICAL_UNIT_RESET);
657                 if (retval) {
658                         ZFCP_LOG_DEBUG("unit reset failed (unit=%p)\n", unit);
659                         if (retval == -ENOTSUPP)
660                                 atomic_set_mask
661                                     (ZFCP_STATUS_UNIT_NOTSUPPUNITRESET,
662                                      &unit->status);
663                         /* fall through and try 'target reset' next */
664                 } else {
665                         ZFCP_LOG_DEBUG("unit reset succeeded (unit=%p)\n",
666                                        unit);
667                         /* avoid 'target reset' */
668                         retval = SUCCESS;
669                         goto out;
670                 }
671         }
672         retval = zfcp_task_management_function(unit, FCP_TARGET_RESET);
673         if (retval) {
674                 ZFCP_LOG_DEBUG("target reset failed (unit=%p)\n", unit);
675                 retval = FAILED;
676         } else {
677                 ZFCP_LOG_DEBUG("target reset succeeded (unit=%p)\n", unit);
678                 retval = SUCCESS;
679         }
680  out:
681         return retval;
682 }
683
684 static int
685 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags)
686 {
687         struct zfcp_adapter *adapter = unit->port->adapter;
688         int retval;
689         int status;
690         struct zfcp_fsf_req *fsf_req;
691
692         /* issue task management function */
693         fsf_req = zfcp_fsf_send_fcp_command_task_management
694                 (adapter, unit, tm_flags, 0);
695         if (!fsf_req) {
696                 ZFCP_LOG_INFO("error: creation of task management request "
697                               "failed for unit 0x%016Lx on port 0x%016Lx on  "
698                               "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
699                               zfcp_get_busid_by_adapter(adapter));
700                 retval = -ENOMEM;
701                 goto out;
702         }
703
704         retval = zfcp_fsf_req_wait_and_cleanup(fsf_req,
705                                                ZFCP_UNINTERRUPTIBLE, &status);
706         /*
707          * check completion status of task management function
708          * (status should always be valid since no signals permitted)
709          */
710         if (status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED)
711                 retval = -EIO;
712         else if (status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP)
713                 retval = -ENOTSUPP;
714         else
715                 retval = 0;
716  out:
717         return retval;
718 }
719
720 /*
721  * function:    zfcp_scsi_eh_bus_reset_handler
722  *
723  * purpose:
724  *
725  * returns:
726  */
727 int
728 zfcp_scsi_eh_bus_reset_handler(struct scsi_cmnd *scpnt)
729 {
730         int retval = 0;
731         struct zfcp_unit *unit;
732         struct Scsi_Host *scsi_host = scpnt->device->host;
733
734         unit = (struct zfcp_unit *) scpnt->device->hostdata;
735         ZFCP_LOG_NORMAL("bus reset because of problems with "
736                         "unit 0x%016Lx\n", unit->fcp_lun);
737         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
738         zfcp_erp_wait(unit->port->adapter);
739         retval = SUCCESS;
740
741         return retval;
742 }
743
744 /*
745  * function:    zfcp_scsi_eh_host_reset_handler
746  *
747  * purpose:
748  *
749  * returns:
750  */
751 int
752 zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
753 {
754         int retval = 0;
755         struct zfcp_unit *unit;
756         struct Scsi_Host *scsi_host = scpnt->device->host;
757
758         unit = (struct zfcp_unit *) scpnt->device->hostdata;
759         ZFCP_LOG_NORMAL("host reset because of problems with "
760                         "unit 0x%016Lx\n", unit->fcp_lun);
761         zfcp_erp_adapter_reopen(unit->port->adapter, 0);
762         zfcp_erp_wait(unit->port->adapter);
763         retval = SUCCESS;
764
765         return retval;
766 }
767
768 /*
769  * function:    
770  *
771  * purpose:     
772  *
773  * returns:
774  */
775 int
776 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
777 {
778         int retval = 0;
779         static unsigned int unique_id = 0;
780
781         /* register adapter as SCSI host with mid layer of SCSI stack */
782         adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
783                                              sizeof (struct zfcp_adapter *));
784         if (!adapter->scsi_host) {
785                 ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
786                                 "for adapter %s ",
787                                 zfcp_get_busid_by_adapter(adapter));
788                 retval = -EIO;
789                 goto out;
790         }
791         ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
792
793         /* tell the SCSI stack some characteristics of this adapter */
794         adapter->scsi_host->max_id = 1;
795         adapter->scsi_host->max_lun = 1;
796         adapter->scsi_host->max_channel = 0;
797         adapter->scsi_host->unique_id = unique_id++;    /* FIXME */
798         adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
799         adapter->scsi_host->transportt = zfcp_transport_template;
800         /*
801          * Reverse mapping of the host number to avoid race condition
802          */
803         adapter->scsi_host_no = adapter->scsi_host->host_no;
804
805         /*
806          * save a pointer to our own adapter data structure within
807          * hostdata field of SCSI host data structure
808          */
809         adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
810
811         if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
812                 scsi_host_put(adapter->scsi_host);
813                 retval = -EIO;
814                 goto out;
815         }
816         atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
817  out:
818         return retval;
819 }
820
821 /*
822  * function:    
823  *
824  * purpose:     
825  *
826  * returns:
827  */
828 void
829 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
830 {
831         struct Scsi_Host *shost;
832
833         shost = adapter->scsi_host;
834         if (!shost)
835                 return;
836         scsi_remove_host(shost);
837         scsi_host_put(shost);
838         adapter->scsi_host = NULL;
839         adapter->scsi_host_no = 0;
840         atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
841
842         return;
843 }
844
845
846 void
847 zfcp_fsf_start_scsi_er_timer(struct zfcp_adapter *adapter)
848 {
849         adapter->scsi_er_timer.function = zfcp_fsf_scsi_er_timeout_handler;
850         adapter->scsi_er_timer.data = (unsigned long) adapter;
851         adapter->scsi_er_timer.expires = jiffies + ZFCP_SCSI_ER_TIMEOUT;
852         add_timer(&adapter->scsi_er_timer);
853 }
854
855 /*
856  * Support functions for FC transport class
857  */
858 static void
859 zfcp_get_port_id(struct scsi_target *starget)
860 {
861         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
862         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
863         struct zfcp_port *port;
864         unsigned long flags;
865
866         read_lock_irqsave(&zfcp_data.config_lock, flags);
867         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
868         if (port)
869                 fc_starget_port_id(starget) = port->d_id;
870         else
871                 fc_starget_port_id(starget) = -1;
872         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
873 }
874
875 static void
876 zfcp_get_port_name(struct scsi_target *starget)
877 {
878         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
879         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
880         struct zfcp_port *port;
881         unsigned long flags;
882
883         read_lock_irqsave(&zfcp_data.config_lock, flags);
884         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
885         if (port)
886                 fc_starget_port_name(starget) = port->wwpn;
887         else
888                 fc_starget_port_name(starget) = -1;
889         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
890 }
891
892 static void
893 zfcp_get_node_name(struct scsi_target *starget)
894 {
895         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
896         struct zfcp_adapter *adapter = (struct zfcp_adapter *)shost->hostdata[0];
897         struct zfcp_port *port;
898         unsigned long flags;
899
900         read_lock_irqsave(&zfcp_data.config_lock, flags);
901         port = zfcp_port_lookup(adapter, starget->channel, starget->id);
902         if (port)
903                 fc_starget_node_name(starget) = port->wwnn;
904         else
905                 fc_starget_node_name(starget) = -1;
906         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
907 }
908
909 struct fc_function_template zfcp_transport_functions = {
910         .get_starget_port_id = zfcp_get_port_id,
911         .get_starget_port_name = zfcp_get_port_name,
912         .get_starget_node_name = zfcp_get_node_name,
913         .show_starget_port_id = 1,
914         .show_starget_port_name = 1,
915         .show_starget_node_name = 1,
916 };
917
918 /**
919  * ZFCP_DEFINE_SCSI_ATTR
920  * @_name:   name of show attribute
921  * @_format: format string
922  * @_value:  value to print
923  *
924  * Generates attribute for a unit.
925  */
926 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
927 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev,        \
928                                               char *buf)                 \
929 {                                                                        \
930         struct scsi_device *sdev;                                        \
931         struct zfcp_unit *unit;                                          \
932                                                                          \
933         sdev = to_scsi_device(dev);                                      \
934         unit = sdev->hostdata;                                           \
935         return sprintf(buf, _format, _value);                            \
936 }                                                                        \
937                                                                          \
938 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
939
940 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
941 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
942 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
943
944 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
945         &dev_attr_fcp_lun,
946         &dev_attr_wwpn,
947         &dev_attr_hba_id,
948         NULL
949 };
950
951 #undef ZFCP_LOG_AREA