xref: /openbmc/linux/drivers/s390/scsi/zfcp_scsi.c (revision f42b3800)
1 /*
2  * This file is part of the zfcp device driver for
3  * FCP adapters for IBM System z9 and zSeries.
4  *
5  * (C) Copyright IBM Corp. 2002, 2006
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2, or (at your option)
10  * any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #define ZFCP_LOG_AREA			ZFCP_LOG_AREA_SCSI
23 
24 #include "zfcp_ext.h"
25 #include <asm/atomic.h>
26 
27 static void zfcp_scsi_slave_destroy(struct scsi_device *sdp);
28 static int zfcp_scsi_slave_alloc(struct scsi_device *sdp);
29 static int zfcp_scsi_slave_configure(struct scsi_device *sdp);
30 static int zfcp_scsi_queuecommand(struct scsi_cmnd *,
31 				  void (*done) (struct scsi_cmnd *));
32 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *);
33 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *);
34 static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *);
35 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *);
36 static int zfcp_task_management_function(struct zfcp_unit *, u8,
37 					 struct scsi_cmnd *);
38 
39 static struct zfcp_unit *zfcp_unit_lookup(struct zfcp_adapter *, int,
40 					  unsigned int, unsigned int);
41 
42 static struct device_attribute *zfcp_sysfs_sdev_attrs[];
43 
44 struct zfcp_data zfcp_data = {
45 	.scsi_host_template = {
46 		.name			= ZFCP_NAME,
47 		.module			= THIS_MODULE,
48 		.proc_name		= "zfcp",
49 		.slave_alloc		= zfcp_scsi_slave_alloc,
50 		.slave_configure	= zfcp_scsi_slave_configure,
51 		.slave_destroy		= zfcp_scsi_slave_destroy,
52 		.queuecommand		= zfcp_scsi_queuecommand,
53 		.eh_abort_handler	= zfcp_scsi_eh_abort_handler,
54 		.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
55 		.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
56 		.eh_host_reset_handler	= zfcp_scsi_eh_host_reset_handler,
57 		.can_queue		= 4096,
58 		.this_id		= -1,
59 		.sg_tablesize		= ZFCP_MAX_SBALES_PER_REQ,
60 		.cmd_per_lun		= 1,
61 		.use_clustering		= 1,
62 		.sdev_attrs		= zfcp_sysfs_sdev_attrs,
63 		.max_sectors		= ZFCP_MAX_SECTORS,
64 	},
65 	.driver_version = ZFCP_VERSION,
66 };
67 
68 /* Find start of Response Information in FCP response unit*/
69 char *
70 zfcp_get_fcp_rsp_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
71 {
72 	char *fcp_rsp_info_ptr;
73 
74 	fcp_rsp_info_ptr =
75 	    (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
76 
77 	return fcp_rsp_info_ptr;
78 }
79 
80 /* Find start of Sense Information in FCP response unit*/
81 char *
82 zfcp_get_fcp_sns_info_ptr(struct fcp_rsp_iu *fcp_rsp_iu)
83 {
84 	char *fcp_sns_info_ptr;
85 
86 	fcp_sns_info_ptr =
87 	    (unsigned char *) fcp_rsp_iu + (sizeof (struct fcp_rsp_iu));
88 	if (fcp_rsp_iu->validity.bits.fcp_rsp_len_valid)
89 		fcp_sns_info_ptr = (char *) fcp_sns_info_ptr +
90 		    fcp_rsp_iu->fcp_rsp_len;
91 
92 	return fcp_sns_info_ptr;
93 }
94 
95 static fcp_dl_t *
96 zfcp_get_fcp_dl_ptr(struct fcp_cmnd_iu * fcp_cmd)
97 {
98 	int additional_length = fcp_cmd->add_fcp_cdb_length << 2;
99 	fcp_dl_t *fcp_dl_addr;
100 
101 	fcp_dl_addr = (fcp_dl_t *)
102 		((unsigned char *) fcp_cmd +
103 		 sizeof (struct fcp_cmnd_iu) + additional_length);
104 	/*
105 	 * fcp_dl_addr = start address of fcp_cmnd structure +
106 	 * size of fixed part + size of dynamically sized add_dcp_cdb field
107 	 * SEE FCP-2 documentation
108 	 */
109 	return fcp_dl_addr;
110 }
111 
112 fcp_dl_t
113 zfcp_get_fcp_dl(struct fcp_cmnd_iu * fcp_cmd)
114 {
115 	return *zfcp_get_fcp_dl_ptr(fcp_cmd);
116 }
117 
118 void
119 zfcp_set_fcp_dl(struct fcp_cmnd_iu *fcp_cmd, fcp_dl_t fcp_dl)
120 {
121 	*zfcp_get_fcp_dl_ptr(fcp_cmd) = fcp_dl;
122 }
123 
124 /*
125  * note: it's a bit-or operation not an assignment
126  * regarding the specified byte
127  */
128 static inline void
129 set_byte(int *result, char status, char pos)
130 {
131 	*result |= status << (pos * 8);
132 }
133 
134 void
135 set_host_byte(int *result, char status)
136 {
137 	set_byte(result, status, 2);
138 }
139 
140 void
141 set_driver_byte(int *result, char status)
142 {
143 	set_byte(result, status, 3);
144 }
145 
146 static int
147 zfcp_scsi_slave_alloc(struct scsi_device *sdp)
148 {
149 	struct zfcp_adapter *adapter;
150 	struct zfcp_unit *unit;
151 	unsigned long flags;
152 	int retval = -ENXIO;
153 
154 	adapter = (struct zfcp_adapter *) sdp->host->hostdata[0];
155 	if (!adapter)
156 		goto out;
157 
158 	read_lock_irqsave(&zfcp_data.config_lock, flags);
159 	unit = zfcp_unit_lookup(adapter, sdp->channel, sdp->id, sdp->lun);
160 	if (unit && atomic_test_mask(ZFCP_STATUS_UNIT_REGISTERED,
161 				     &unit->status)) {
162 		sdp->hostdata = unit;
163 		unit->device = sdp;
164 		zfcp_unit_get(unit);
165 		retval = 0;
166 	}
167 	read_unlock_irqrestore(&zfcp_data.config_lock, flags);
168  out:
169 	return retval;
170 }
171 
172 /**
173  * zfcp_scsi_slave_destroy - called when scsi device is removed
174  *
175  * Remove reference to associated scsi device for an zfcp_unit.
176  * Mark zfcp_unit as failed. The scsi device might be deleted via sysfs
177  * or a scan for this device might have failed.
178  */
179 static void zfcp_scsi_slave_destroy(struct scsi_device *sdpnt)
180 {
181 	struct zfcp_unit *unit = (struct zfcp_unit *) sdpnt->hostdata;
182 
183 	if (unit) {
184 		atomic_clear_mask(ZFCP_STATUS_UNIT_REGISTERED, &unit->status);
185 		sdpnt->hostdata = NULL;
186 		unit->device = NULL;
187 		zfcp_erp_unit_failed(unit, 12, NULL);
188 		zfcp_unit_put(unit);
189 	} else
190 		ZFCP_LOG_NORMAL("bug: no unit associated with SCSI device at "
191 				"address %p\n", sdpnt);
192 }
193 
194 /*
195  * called from scsi midlayer to allow finetuning of a device.
196  */
197 static int
198 zfcp_scsi_slave_configure(struct scsi_device *sdp)
199 {
200 	if (sdp->tagged_supported)
201 		scsi_adjust_queue_depth(sdp, MSG_SIMPLE_TAG, ZFCP_CMND_PER_LUN);
202 	else
203 		scsi_adjust_queue_depth(sdp, 0, 1);
204 	return 0;
205 }
206 
207 /**
208  * zfcp_scsi_command_fail - set result in scsi_cmnd and call scsi_done function
209  * @scpnt: pointer to struct scsi_cmnd where result is set
210  * @result: result to be set in scpnt (e.g. DID_ERROR)
211  */
212 static void
213 zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
214 {
215 	set_host_byte(&scpnt->result, result);
216 	if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
217 		zfcp_scsi_dbf_event_result("fail", 4,
218 			(struct zfcp_adapter*) scpnt->device->host->hostdata[0],
219 			scpnt, NULL);
220 	/* return directly */
221 	scpnt->scsi_done(scpnt);
222 }
223 
224 /**
225  * zfcp_scsi_command_async - worker for zfcp_scsi_queuecommand and
226  *	zfcp_scsi_command_sync
227  * @adapter: adapter where scsi command is issued
228  * @unit: unit to which scsi command is sent
229  * @scpnt: scsi command to be sent
230  * @timer: timer to be started if request is successfully initiated
231  *
232  * Note: In scsi_done function must be set in scpnt.
233  */
234 int
235 zfcp_scsi_command_async(struct zfcp_adapter *adapter, struct zfcp_unit *unit,
236 			struct scsi_cmnd *scpnt, int use_timer)
237 {
238 	int tmp;
239 	int retval;
240 
241 	retval = 0;
242 
243 	BUG_ON((adapter == NULL) || (adapter != unit->port->adapter));
244 	BUG_ON(scpnt->scsi_done == NULL);
245 
246 	if (unlikely(NULL == unit)) {
247 		zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
248 		goto out;
249 	}
250 
251 	if (unlikely(
252 	      atomic_test_mask(ZFCP_STATUS_COMMON_ERP_FAILED, &unit->status) ||
253 	     !atomic_test_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status))) {
254 		ZFCP_LOG_DEBUG("stopping SCSI I/O on unit 0x%016Lx on port "
255 			       "0x%016Lx on adapter %s\n",
256 			       unit->fcp_lun, unit->port->wwpn,
257 			       zfcp_get_busid_by_adapter(adapter));
258 		zfcp_scsi_command_fail(scpnt, DID_ERROR);
259 		goto out;
260 	}
261 
262 	tmp = zfcp_fsf_send_fcp_command_task(adapter, unit, scpnt, use_timer,
263 					     ZFCP_REQ_AUTO_CLEANUP);
264 	if (unlikely(tmp == -EBUSY)) {
265 		ZFCP_LOG_DEBUG("adapter %s not ready or unit 0x%016Lx "
266 			       "on port 0x%016Lx in recovery\n",
267 			       zfcp_get_busid_by_unit(unit),
268 			       unit->fcp_lun, unit->port->wwpn);
269 		zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
270 		goto out;
271 	}
272 
273 	if (unlikely(tmp < 0)) {
274 		ZFCP_LOG_DEBUG("error: initiation of Send FCP Cmnd failed\n");
275 		retval = SCSI_MLQUEUE_HOST_BUSY;
276 	}
277 
278 out:
279 	return retval;
280 }
281 
282 static void
283 zfcp_scsi_command_sync_handler(struct scsi_cmnd *scpnt)
284 {
285 	struct completion *wait = (struct completion *) scpnt->SCp.ptr;
286 	complete(wait);
287 }
288 
289 
290 /**
291  * zfcp_scsi_command_sync - send a SCSI command and wait for completion
292  * @unit: unit where command is sent to
293  * @scpnt: scsi command to be sent
294  * @use_timer: indicates whether timer should be setup or not
295  * Return: 0
296  *
297  * Errors are indicated in scpnt->result
298  */
299 int
300 zfcp_scsi_command_sync(struct zfcp_unit *unit, struct scsi_cmnd *scpnt,
301 		       int use_timer)
302 {
303 	int ret;
304 	DECLARE_COMPLETION_ONSTACK(wait);
305 
306 	scpnt->SCp.ptr = (void *) &wait;  /* silent re-use */
307 	scpnt->scsi_done = zfcp_scsi_command_sync_handler;
308 	ret = zfcp_scsi_command_async(unit->port->adapter, unit, scpnt,
309 				      use_timer);
310 	if (ret == 0)
311 		wait_for_completion(&wait);
312 
313 	scpnt->SCp.ptr = NULL;
314 
315 	return 0;
316 }
317 
318 /*
319  * function:	zfcp_scsi_queuecommand
320  *
321  * purpose:	enqueues a SCSI command to the specified target device
322  *
323  * returns:	0 - success, SCSI command enqueued
324  *		!0 - failure
325  */
326 static int
327 zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
328 		       void (*done) (struct scsi_cmnd *))
329 {
330 	struct zfcp_unit *unit;
331 	struct zfcp_adapter *adapter;
332 
333 	/* reset the status for this request */
334 	scpnt->result = 0;
335 	scpnt->host_scribble = NULL;
336 	scpnt->scsi_done = done;
337 
338 	/*
339 	 * figure out adapter and target device
340 	 * (stored there by zfcp_scsi_slave_alloc)
341 	 */
342 	adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
343 	unit = (struct zfcp_unit *) scpnt->device->hostdata;
344 
345 	return zfcp_scsi_command_async(adapter, unit, scpnt, 0);
346 }
347 
348 static struct zfcp_unit *
349 zfcp_unit_lookup(struct zfcp_adapter *adapter, int channel, unsigned int id,
350 		 unsigned int lun)
351 {
352 	struct zfcp_port *port;
353 	struct zfcp_unit *unit, *retval = NULL;
354 
355 	list_for_each_entry(port, &adapter->port_list_head, list) {
356 		if (!port->rport || (id != port->rport->scsi_target_id))
357 			continue;
358 		list_for_each_entry(unit, &port->unit_list_head, list)
359 			if (lun == unit->scsi_lun) {
360 				retval = unit;
361 				goto out;
362 			}
363 	}
364  out:
365 	return retval;
366 }
367 
368 /**
369  * zfcp_scsi_eh_abort_handler - abort the specified SCSI command
370  * @scpnt: pointer to scsi_cmnd to be aborted
371  * Return: SUCCESS - command has been aborted and cleaned up in internal
372  *          bookkeeping, SCSI stack won't be called for aborted command
373  *         FAILED - otherwise
374  *
375  * We do not need to care for a SCSI command which completes normally
376  * but late during this abort routine runs.  We are allowed to return
377  * late commands to the SCSI stack.  It tracks the state of commands and
378  * will handle late commands.  (Usually, the normal completion of late
379  * commands is ignored with respect to the running abort operation.)
380  */
381 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
382 {
383  	struct Scsi_Host *scsi_host;
384  	struct zfcp_adapter *adapter;
385 	struct zfcp_unit *unit;
386 	struct zfcp_fsf_req *fsf_req;
387 	unsigned long flags;
388 	unsigned long old_req_id;
389 	int retval = SUCCESS;
390 
391 	scsi_host = scpnt->device->host;
392 	adapter = (struct zfcp_adapter *) scsi_host->hostdata[0];
393 	unit = (struct zfcp_unit *) scpnt->device->hostdata;
394 
395 	ZFCP_LOG_INFO("aborting scsi_cmnd=%p on adapter %s\n",
396 		      scpnt, zfcp_get_busid_by_adapter(adapter));
397 
398 	/* avoid race condition between late normal completion and abort */
399 	write_lock_irqsave(&adapter->abort_lock, flags);
400 
401 	/* Check whether corresponding fsf_req is still pending */
402 	spin_lock(&adapter->req_list_lock);
403 	fsf_req = zfcp_reqlist_find(adapter,
404 				    (unsigned long) scpnt->host_scribble);
405 	spin_unlock(&adapter->req_list_lock);
406 	if (!fsf_req) {
407 		write_unlock_irqrestore(&adapter->abort_lock, flags);
408 		zfcp_scsi_dbf_event_abort("lte1", adapter, scpnt, NULL, 0);
409 		retval = SUCCESS;
410 		goto out;
411 	}
412 	fsf_req->data = 0;
413 	fsf_req->status |= ZFCP_STATUS_FSFREQ_ABORTING;
414 	old_req_id = fsf_req->req_id;
415 
416 	/* don't access old fsf_req after releasing the abort_lock */
417 	write_unlock_irqrestore(&adapter->abort_lock, flags);
418 
419 	fsf_req = zfcp_fsf_abort_fcp_command(old_req_id, adapter, unit, 0);
420 	if (!fsf_req) {
421 		ZFCP_LOG_INFO("error: initiation of Abort FCP Cmnd failed\n");
422 		zfcp_scsi_dbf_event_abort("nres", adapter, scpnt, NULL,
423 					  old_req_id);
424 		retval = FAILED;
425 		goto out;
426 	}
427 
428 	__wait_event(fsf_req->completion_wq,
429 		     fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
430 
431 	if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED) {
432 		zfcp_scsi_dbf_event_abort("okay", adapter, scpnt, fsf_req, 0);
433 		retval = SUCCESS;
434 	} else if (fsf_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED) {
435 		zfcp_scsi_dbf_event_abort("lte2", adapter, scpnt, fsf_req, 0);
436 		retval = SUCCESS;
437 	} else {
438 		zfcp_scsi_dbf_event_abort("fail", adapter, scpnt, fsf_req, 0);
439 		retval = FAILED;
440 	}
441 	zfcp_fsf_req_free(fsf_req);
442  out:
443 	return retval;
444 }
445 
446 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
447 {
448 	int retval;
449 	struct zfcp_unit *unit = scpnt->device->hostdata;
450 
451 	if (!unit) {
452 		WARN_ON(1);
453 		return SUCCESS;
454 	}
455 	retval = zfcp_task_management_function(unit,
456 					       FCP_LOGICAL_UNIT_RESET,
457 					       scpnt);
458 	return retval ? FAILED : SUCCESS;
459 }
460 
461 static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
462 {
463 	int retval;
464 	struct zfcp_unit *unit = scpnt->device->hostdata;
465 
466 	if (!unit) {
467 		WARN_ON(1);
468 		return SUCCESS;
469 	}
470 	retval = zfcp_task_management_function(unit, FCP_TARGET_RESET, scpnt);
471 	return retval ? FAILED : SUCCESS;
472 }
473 
474 static int
475 zfcp_task_management_function(struct zfcp_unit *unit, u8 tm_flags,
476 			      struct scsi_cmnd *scpnt)
477 {
478 	struct zfcp_adapter *adapter = unit->port->adapter;
479 	struct zfcp_fsf_req *fsf_req;
480 	int retval = 0;
481 
482 	/* issue task management function */
483 	fsf_req = zfcp_fsf_send_fcp_command_task_management
484 		(adapter, unit, tm_flags, 0);
485 	if (!fsf_req) {
486 		ZFCP_LOG_INFO("error: creation of task management request "
487 			      "failed for unit 0x%016Lx on port 0x%016Lx on  "
488 			      "adapter %s\n", unit->fcp_lun, unit->port->wwpn,
489 			      zfcp_get_busid_by_adapter(adapter));
490 		zfcp_scsi_dbf_event_devreset("nres", tm_flags, unit, scpnt);
491 		retval = -ENOMEM;
492 		goto out;
493 	}
494 
495 	__wait_event(fsf_req->completion_wq,
496 		     fsf_req->status & ZFCP_STATUS_FSFREQ_COMPLETED);
497 
498 	/*
499 	 * check completion status of task management function
500 	 */
501 	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
502 		zfcp_scsi_dbf_event_devreset("fail", tm_flags, unit, scpnt);
503 		retval = -EIO;
504 	} else if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCNOTSUPP) {
505 		zfcp_scsi_dbf_event_devreset("nsup", tm_flags, unit, scpnt);
506 		retval = -ENOTSUPP;
507 	} else
508 		zfcp_scsi_dbf_event_devreset("okay", tm_flags, unit, scpnt);
509 
510 	zfcp_fsf_req_free(fsf_req);
511  out:
512 	return retval;
513 }
514 
515 /**
516  * zfcp_scsi_eh_host_reset_handler - handler for host reset
517  */
518 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
519 {
520 	struct zfcp_unit *unit;
521 	struct zfcp_adapter *adapter;
522 
523 	unit = (struct zfcp_unit*) scpnt->device->hostdata;
524 	adapter = unit->port->adapter;
525 
526 	ZFCP_LOG_NORMAL("host reset because of problems with "
527 		"unit 0x%016Lx on port 0x%016Lx, adapter %s\n",
528 		unit->fcp_lun, unit->port->wwpn,
529 		zfcp_get_busid_by_adapter(unit->port->adapter));
530 
531 	zfcp_erp_adapter_reopen(adapter, 0, 141, scpnt);
532 	zfcp_erp_wait(adapter);
533 
534 	return SUCCESS;
535 }
536 
537 int
538 zfcp_adapter_scsi_register(struct zfcp_adapter *adapter)
539 {
540 	int retval = 0;
541 	static unsigned int unique_id = 0;
542 
543 	if (adapter->scsi_host)
544 		goto out;
545 
546 	/* register adapter as SCSI host with mid layer of SCSI stack */
547 	adapter->scsi_host = scsi_host_alloc(&zfcp_data.scsi_host_template,
548 					     sizeof (struct zfcp_adapter *));
549 	if (!adapter->scsi_host) {
550 		ZFCP_LOG_NORMAL("error: registration with SCSI stack failed "
551 				"for adapter %s ",
552 				zfcp_get_busid_by_adapter(adapter));
553 		retval = -EIO;
554 		goto out;
555 	}
556 	ZFCP_LOG_DEBUG("host registered, scsi_host=%p\n", adapter->scsi_host);
557 
558 	/* tell the SCSI stack some characteristics of this adapter */
559 	adapter->scsi_host->max_id = 1;
560 	adapter->scsi_host->max_lun = 1;
561 	adapter->scsi_host->max_channel = 0;
562 	adapter->scsi_host->unique_id = unique_id++;	/* FIXME */
563 	adapter->scsi_host->max_cmd_len = ZFCP_MAX_SCSI_CMND_LENGTH;
564 	adapter->scsi_host->transportt = zfcp_data.scsi_transport_template;
565 
566 	/*
567 	 * save a pointer to our own adapter data structure within
568 	 * hostdata field of SCSI host data structure
569 	 */
570 	adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
571 
572 	if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
573 		scsi_host_put(adapter->scsi_host);
574 		retval = -EIO;
575 		goto out;
576 	}
577 	atomic_set_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
578  out:
579 	return retval;
580 }
581 
582 void
583 zfcp_adapter_scsi_unregister(struct zfcp_adapter *adapter)
584 {
585 	struct Scsi_Host *shost;
586 	struct zfcp_port *port;
587 
588 	shost = adapter->scsi_host;
589 	if (!shost)
590 		return;
591 	read_lock_irq(&zfcp_data.config_lock);
592 	list_for_each_entry(port, &adapter->port_list_head, list)
593 		if (port->rport)
594 			port->rport = NULL;
595 	read_unlock_irq(&zfcp_data.config_lock);
596 	fc_remove_host(shost);
597 	scsi_remove_host(shost);
598 	scsi_host_put(shost);
599 	adapter->scsi_host = NULL;
600 	atomic_clear_mask(ZFCP_STATUS_ADAPTER_REGISTERED, &adapter->status);
601 
602 	return;
603 }
604 
605 /*
606  * Support functions for FC transport class
607  */
608 static struct fc_host_statistics*
609 zfcp_init_fc_host_stats(struct zfcp_adapter *adapter)
610 {
611 	struct fc_host_statistics *fc_stats;
612 
613 	if (!adapter->fc_stats) {
614 		fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
615 		if (!fc_stats)
616 			return NULL;
617 		adapter->fc_stats = fc_stats; /* freed in adater_dequeue */
618 	}
619 	memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
620 	return adapter->fc_stats;
621 }
622 
623 static void
624 zfcp_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
625 			  struct fsf_qtcb_bottom_port *data,
626 			  struct fsf_qtcb_bottom_port *old)
627 {
628 	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset -
629 		old->seconds_since_last_reset;
630 	fc_stats->tx_frames = data->tx_frames - old->tx_frames;
631 	fc_stats->tx_words = data->tx_words - old->tx_words;
632 	fc_stats->rx_frames = data->rx_frames - old->rx_frames;
633 	fc_stats->rx_words = data->rx_words - old->rx_words;
634 	fc_stats->lip_count = data->lip - old->lip;
635 	fc_stats->nos_count = data->nos - old->nos;
636 	fc_stats->error_frames = data->error_frames - old->error_frames;
637 	fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
638 	fc_stats->link_failure_count = data->link_failure - old->link_failure;
639 	fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
640 	fc_stats->loss_of_signal_count = data->loss_of_signal -
641 		old->loss_of_signal;
642 	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts -
643 		old->psp_error_counts;
644 	fc_stats->invalid_tx_word_count = data->invalid_tx_words -
645 		old->invalid_tx_words;
646 	fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
647 	fc_stats->fcp_input_requests = data->input_requests -
648 		old->input_requests;
649 	fc_stats->fcp_output_requests = data->output_requests -
650 		old->output_requests;
651 	fc_stats->fcp_control_requests = data->control_requests -
652 		old->control_requests;
653 	fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
654 	fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
655 }
656 
657 static void
658 zfcp_set_fc_host_stats(struct fc_host_statistics *fc_stats,
659 		       struct fsf_qtcb_bottom_port *data)
660 {
661 	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
662 	fc_stats->tx_frames = data->tx_frames;
663 	fc_stats->tx_words = data->tx_words;
664 	fc_stats->rx_frames = data->rx_frames;
665 	fc_stats->rx_words = data->rx_words;
666 	fc_stats->lip_count = data->lip;
667 	fc_stats->nos_count = data->nos;
668 	fc_stats->error_frames = data->error_frames;
669 	fc_stats->dumped_frames = data->dumped_frames;
670 	fc_stats->link_failure_count = data->link_failure;
671 	fc_stats->loss_of_sync_count = data->loss_of_sync;
672 	fc_stats->loss_of_signal_count = data->loss_of_signal;
673 	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
674 	fc_stats->invalid_tx_word_count = data->invalid_tx_words;
675 	fc_stats->invalid_crc_count = data->invalid_crcs;
676 	fc_stats->fcp_input_requests = data->input_requests;
677 	fc_stats->fcp_output_requests = data->output_requests;
678 	fc_stats->fcp_control_requests = data->control_requests;
679 	fc_stats->fcp_input_megabytes = data->input_mb;
680 	fc_stats->fcp_output_megabytes = data->output_mb;
681 }
682 
683 /**
684  * zfcp_get_fc_host_stats - provide fc_host_statistics for scsi_transport_fc
685  *
686  * assumption: scsi_transport_fc synchronizes calls of
687  *             get_fc_host_stats and reset_fc_host_stats
688  *             (XXX to be checked otherwise introduce locking)
689  */
690 static struct fc_host_statistics *
691 zfcp_get_fc_host_stats(struct Scsi_Host *shost)
692 {
693 	struct zfcp_adapter *adapter;
694 	struct fc_host_statistics *fc_stats;
695 	struct fsf_qtcb_bottom_port *data;
696 	int ret;
697 
698 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
699 	fc_stats = zfcp_init_fc_host_stats(adapter);
700 	if (!fc_stats)
701 		return NULL;
702 
703 	data = kzalloc(sizeof(*data), GFP_KERNEL);
704 	if (!data)
705 		return NULL;
706 
707 	ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
708 	if (ret) {
709 		kfree(data);
710 		return NULL; /* XXX return zeroed fc_stats? */
711 	}
712 
713 	if (adapter->stats_reset &&
714 	    ((jiffies/HZ - adapter->stats_reset) <
715 	     data->seconds_since_last_reset)) {
716 		zfcp_adjust_fc_host_stats(fc_stats, data,
717 					  adapter->stats_reset_data);
718 	} else
719 		zfcp_set_fc_host_stats(fc_stats, data);
720 
721 	kfree(data);
722 	return fc_stats;
723 }
724 
725 static void
726 zfcp_reset_fc_host_stats(struct Scsi_Host *shost)
727 {
728 	struct zfcp_adapter *adapter;
729 	struct fsf_qtcb_bottom_port *data, *old_data;
730 	int ret;
731 
732 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
733 	data = kzalloc(sizeof(*data), GFP_KERNEL);
734 	if (!data)
735 		return;
736 
737 	ret = zfcp_fsf_exchange_port_data_sync(adapter, data);
738 	if (ret) {
739 		kfree(data);
740 	} else {
741 		adapter->stats_reset = jiffies/HZ;
742 		old_data = adapter->stats_reset_data;
743 		adapter->stats_reset_data = data; /* finally freed in
744 						     adater_dequeue */
745 		kfree(old_data);
746 	}
747 }
748 
749 static void zfcp_set_rport_dev_loss_tmo(struct fc_rport *rport, u32 timeout)
750 {
751 	rport->dev_loss_tmo = timeout;
752 }
753 
754 struct fc_function_template zfcp_transport_functions = {
755 	.show_starget_port_id = 1,
756 	.show_starget_port_name = 1,
757 	.show_starget_node_name = 1,
758 	.show_rport_supported_classes = 1,
759 	.show_rport_maxframe_size = 1,
760 	.show_rport_dev_loss_tmo = 1,
761 	.show_host_node_name = 1,
762 	.show_host_port_name = 1,
763 	.show_host_permanent_port_name = 1,
764 	.show_host_supported_classes = 1,
765 	.show_host_supported_speeds = 1,
766 	.show_host_maxframe_size = 1,
767 	.show_host_serial_number = 1,
768 	.get_fc_host_stats = zfcp_get_fc_host_stats,
769 	.reset_fc_host_stats = zfcp_reset_fc_host_stats,
770 	.set_rport_dev_loss_tmo = zfcp_set_rport_dev_loss_tmo,
771 	/* no functions registered for following dynamic attributes but
772 	   directly set by LLDD */
773 	.show_host_port_type = 1,
774 	.show_host_speed = 1,
775 	.show_host_port_id = 1,
776 	.disable_target_scan = 1,
777 };
778 
779 /**
780  * ZFCP_DEFINE_SCSI_ATTR
781  * @_name:   name of show attribute
782  * @_format: format string
783  * @_value:  value to print
784  *
785  * Generates attribute for a unit.
786  */
787 #define ZFCP_DEFINE_SCSI_ATTR(_name, _format, _value)                    \
788 static ssize_t zfcp_sysfs_scsi_##_name##_show(struct device *dev, struct device_attribute *attr,        \
789                                               char *buf)                 \
790 {                                                                        \
791         struct scsi_device *sdev;                                        \
792         struct zfcp_unit *unit;                                          \
793                                                                          \
794         sdev = to_scsi_device(dev);                                      \
795         unit = sdev->hostdata;                                           \
796         return sprintf(buf, _format, _value);                            \
797 }                                                                        \
798                                                                          \
799 static DEVICE_ATTR(_name, S_IRUGO, zfcp_sysfs_scsi_##_name##_show, NULL);
800 
801 ZFCP_DEFINE_SCSI_ATTR(hba_id, "%s\n", zfcp_get_busid_by_unit(unit));
802 ZFCP_DEFINE_SCSI_ATTR(wwpn, "0x%016llx\n", unit->port->wwpn);
803 ZFCP_DEFINE_SCSI_ATTR(fcp_lun, "0x%016llx\n", unit->fcp_lun);
804 
805 static struct device_attribute *zfcp_sysfs_sdev_attrs[] = {
806 	&dev_attr_fcp_lun,
807 	&dev_attr_wwpn,
808 	&dev_attr_hba_id,
809 	NULL
810 };
811 
812 #undef ZFCP_LOG_AREA
813