xref: /openbmc/linux/drivers/s390/scsi/zfcp_scsi.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * zfcp device driver
4  *
5  * Interface to Linux SCSI midlayer.
6  *
7  * Copyright IBM Corp. 2002, 2018
8  */
9 
10 #define KMSG_COMPONENT "zfcp"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/slab.h>
16 #include <scsi/fc/fc_fcp.h>
17 #include <scsi/scsi_eh.h>
18 #include <linux/atomic.h>
19 #include "zfcp_ext.h"
20 #include "zfcp_dbf.h"
21 #include "zfcp_fc.h"
22 #include "zfcp_reqlist.h"
23 
24 static unsigned int default_depth = 32;
25 module_param_named(queue_depth, default_depth, uint, 0600);
26 MODULE_PARM_DESC(queue_depth, "Default queue depth for new SCSI devices");
27 
28 static bool enable_dif;
29 module_param_named(dif, enable_dif, bool, 0400);
30 MODULE_PARM_DESC(dif, "Enable DIF data integrity support (default off)");
31 
32 bool zfcp_experimental_dix;
33 module_param_named(dix, zfcp_experimental_dix, bool, 0400);
34 MODULE_PARM_DESC(dix, "Enable experimental DIX (data integrity extension) support which implies DIF support (default off)");
35 
36 static bool allow_lun_scan = true;
37 module_param(allow_lun_scan, bool, 0600);
38 MODULE_PARM_DESC(allow_lun_scan, "For NPIV, scan and attach all storage LUNs");
39 
40 static void zfcp_scsi_slave_destroy(struct scsi_device *sdev)
41 {
42 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
43 
44 	/* if previous slave_alloc returned early, there is nothing to do */
45 	if (!zfcp_sdev->port)
46 		return;
47 
48 	zfcp_erp_lun_shutdown_wait(sdev, "scssd_1");
49 	put_device(&zfcp_sdev->port->dev);
50 }
51 
52 static int zfcp_scsi_slave_configure(struct scsi_device *sdp)
53 {
54 	if (sdp->tagged_supported)
55 		scsi_change_queue_depth(sdp, default_depth);
56 	return 0;
57 }
58 
59 static void zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
60 {
61 	set_host_byte(scpnt, result);
62 	zfcp_dbf_scsi_fail_send(scpnt);
63 	scpnt->scsi_done(scpnt);
64 }
65 
66 static
67 int zfcp_scsi_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scpnt)
68 {
69 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
70 	struct fc_rport *rport = starget_to_rport(scsi_target(scpnt->device));
71 	int    status, scsi_result, ret;
72 
73 	/* reset the status for this request */
74 	scpnt->result = 0;
75 	scpnt->host_scribble = NULL;
76 
77 	scsi_result = fc_remote_port_chkready(rport);
78 	if (unlikely(scsi_result)) {
79 		scpnt->result = scsi_result;
80 		zfcp_dbf_scsi_fail_send(scpnt);
81 		scpnt->scsi_done(scpnt);
82 		return 0;
83 	}
84 
85 	status = atomic_read(&zfcp_sdev->status);
86 	if (unlikely(status & ZFCP_STATUS_COMMON_ERP_FAILED) &&
87 		     !(atomic_read(&zfcp_sdev->port->status) &
88 		       ZFCP_STATUS_COMMON_ERP_FAILED)) {
89 		/* only LUN access denied, but port is good
90 		 * not covered by FC transport, have to fail here */
91 		zfcp_scsi_command_fail(scpnt, DID_ERROR);
92 		return 0;
93 	}
94 
95 	if (unlikely(!(status & ZFCP_STATUS_COMMON_UNBLOCKED))) {
96 		/* This could be
97 		 * call to rport_delete pending: mimic retry from
98 		 * 	fc_remote_port_chkready until rport is BLOCKED
99 		 */
100 		zfcp_scsi_command_fail(scpnt, DID_IMM_RETRY);
101 		return 0;
102 	}
103 
104 	ret = zfcp_fsf_fcp_cmnd(scpnt);
105 	if (unlikely(ret == -EBUSY))
106 		return SCSI_MLQUEUE_DEVICE_BUSY;
107 	else if (unlikely(ret < 0))
108 		return SCSI_MLQUEUE_HOST_BUSY;
109 
110 	return ret;
111 }
112 
113 static int zfcp_scsi_slave_alloc(struct scsi_device *sdev)
114 {
115 	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
116 	struct zfcp_adapter *adapter =
117 		(struct zfcp_adapter *) sdev->host->hostdata[0];
118 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
119 	struct zfcp_port *port;
120 	struct zfcp_unit *unit;
121 	int npiv = adapter->connection_features & FSF_FEATURE_NPIV_MODE;
122 
123 	zfcp_sdev->erp_action.adapter = adapter;
124 	zfcp_sdev->erp_action.sdev = sdev;
125 
126 	port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
127 	if (!port)
128 		return -ENXIO;
129 
130 	zfcp_sdev->erp_action.port = port;
131 
132 	mutex_lock(&zfcp_sysfs_port_units_mutex);
133 	if (zfcp_sysfs_port_is_removing(port)) {
134 		/* port is already gone */
135 		mutex_unlock(&zfcp_sysfs_port_units_mutex);
136 		put_device(&port->dev); /* undo zfcp_get_port_by_wwpn() */
137 		return -ENXIO;
138 	}
139 	mutex_unlock(&zfcp_sysfs_port_units_mutex);
140 
141 	unit = zfcp_unit_find(port, zfcp_scsi_dev_lun(sdev));
142 	if (unit)
143 		put_device(&unit->dev);
144 
145 	if (!unit && !(allow_lun_scan && npiv)) {
146 		put_device(&port->dev);
147 		return -ENXIO;
148 	}
149 
150 	zfcp_sdev->port = port;
151 	zfcp_sdev->latencies.write.channel.min = 0xFFFFFFFF;
152 	zfcp_sdev->latencies.write.fabric.min = 0xFFFFFFFF;
153 	zfcp_sdev->latencies.read.channel.min = 0xFFFFFFFF;
154 	zfcp_sdev->latencies.read.fabric.min = 0xFFFFFFFF;
155 	zfcp_sdev->latencies.cmd.channel.min = 0xFFFFFFFF;
156 	zfcp_sdev->latencies.cmd.fabric.min = 0xFFFFFFFF;
157 	spin_lock_init(&zfcp_sdev->latencies.lock);
158 
159 	zfcp_erp_set_lun_status(sdev, ZFCP_STATUS_COMMON_RUNNING);
160 	zfcp_erp_lun_reopen(sdev, 0, "scsla_1");
161 	zfcp_erp_wait(port->adapter);
162 
163 	return 0;
164 }
165 
166 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
167 {
168 	struct Scsi_Host *scsi_host = scpnt->device->host;
169 	struct zfcp_adapter *adapter =
170 		(struct zfcp_adapter *) scsi_host->hostdata[0];
171 	struct zfcp_fsf_req *old_req, *abrt_req;
172 	unsigned long flags;
173 	unsigned long old_reqid = (unsigned long) scpnt->host_scribble;
174 	int retval = SUCCESS, ret;
175 	int retry = 3;
176 	char *dbf_tag;
177 
178 	/* avoid race condition between late normal completion and abort */
179 	write_lock_irqsave(&adapter->abort_lock, flags);
180 
181 	old_req = zfcp_reqlist_find(adapter->req_list, old_reqid);
182 	if (!old_req) {
183 		write_unlock_irqrestore(&adapter->abort_lock, flags);
184 		zfcp_dbf_scsi_abort("abrt_or", scpnt, NULL);
185 		return FAILED; /* completion could be in progress */
186 	}
187 	old_req->data = NULL;
188 
189 	/* don't access old fsf_req after releasing the abort_lock */
190 	write_unlock_irqrestore(&adapter->abort_lock, flags);
191 
192 	while (retry--) {
193 		abrt_req = zfcp_fsf_abort_fcp_cmnd(scpnt);
194 		if (abrt_req)
195 			break;
196 
197 		zfcp_dbf_scsi_abort("abrt_wt", scpnt, NULL);
198 		zfcp_erp_wait(adapter);
199 		ret = fc_block_scsi_eh(scpnt);
200 		if (ret) {
201 			zfcp_dbf_scsi_abort("abrt_bl", scpnt, NULL);
202 			return ret;
203 		}
204 		if (!(atomic_read(&adapter->status) &
205 		      ZFCP_STATUS_COMMON_RUNNING)) {
206 			zfcp_dbf_scsi_abort("abrt_ru", scpnt, NULL);
207 			return SUCCESS;
208 		}
209 	}
210 	if (!abrt_req) {
211 		zfcp_dbf_scsi_abort("abrt_ar", scpnt, NULL);
212 		return FAILED;
213 	}
214 
215 	wait_for_completion(&abrt_req->completion);
216 
217 	if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED)
218 		dbf_tag = "abrt_ok";
219 	else if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED)
220 		dbf_tag = "abrt_nn";
221 	else {
222 		dbf_tag = "abrt_fa";
223 		retval = FAILED;
224 	}
225 	zfcp_dbf_scsi_abort(dbf_tag, scpnt, abrt_req);
226 	zfcp_fsf_req_free(abrt_req);
227 	return retval;
228 }
229 
230 struct zfcp_scsi_req_filter {
231 	u8 tmf_scope;
232 	u32 lun_handle;
233 	u32 port_handle;
234 };
235 
236 static void zfcp_scsi_forget_cmnd(struct zfcp_fsf_req *old_req, void *data)
237 {
238 	struct zfcp_scsi_req_filter *filter =
239 		(struct zfcp_scsi_req_filter *)data;
240 
241 	/* already aborted - prevent side-effects - or not a SCSI command */
242 	if (old_req->data == NULL ||
243 	    zfcp_fsf_req_is_status_read_buffer(old_req) ||
244 	    old_req->qtcb->header.fsf_command != FSF_QTCB_FCP_CMND)
245 		return;
246 
247 	/* (tmf_scope == FCP_TMF_TGT_RESET || tmf_scope == FCP_TMF_LUN_RESET) */
248 	if (old_req->qtcb->header.port_handle != filter->port_handle)
249 		return;
250 
251 	if (filter->tmf_scope == FCP_TMF_LUN_RESET &&
252 	    old_req->qtcb->header.lun_handle != filter->lun_handle)
253 		return;
254 
255 	zfcp_dbf_scsi_nullcmnd((struct scsi_cmnd *)old_req->data, old_req);
256 	old_req->data = NULL;
257 }
258 
259 static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev *zsdev, u8 tm_flags)
260 {
261 	struct zfcp_adapter *adapter = zsdev->port->adapter;
262 	struct zfcp_scsi_req_filter filter = {
263 		.tmf_scope = FCP_TMF_TGT_RESET,
264 		.port_handle = zsdev->port->handle,
265 	};
266 	unsigned long flags;
267 
268 	if (tm_flags == FCP_TMF_LUN_RESET) {
269 		filter.tmf_scope = FCP_TMF_LUN_RESET;
270 		filter.lun_handle = zsdev->lun_handle;
271 	}
272 
273 	/*
274 	 * abort_lock secures against other processings - in the abort-function
275 	 * and normal cmnd-handler - of (struct zfcp_fsf_req *)->data
276 	 */
277 	write_lock_irqsave(&adapter->abort_lock, flags);
278 	zfcp_reqlist_apply_for_all(adapter->req_list, zfcp_scsi_forget_cmnd,
279 				   &filter);
280 	write_unlock_irqrestore(&adapter->abort_lock, flags);
281 }
282 
283 /**
284  * zfcp_scsi_task_mgmt_function() - Send a task management function (sync).
285  * @sdev: Pointer to SCSI device to send the task management command to.
286  * @tm_flags: Task management flags,
287  *	      here we only handle %FCP_TMF_TGT_RESET or %FCP_TMF_LUN_RESET.
288  */
289 static int zfcp_scsi_task_mgmt_function(struct scsi_device *sdev, u8 tm_flags)
290 {
291 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
292 	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
293 	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
294 	struct zfcp_fsf_req *fsf_req = NULL;
295 	int retval = SUCCESS, ret;
296 	int retry = 3;
297 
298 	while (retry--) {
299 		fsf_req = zfcp_fsf_fcp_task_mgmt(sdev, tm_flags);
300 		if (fsf_req)
301 			break;
302 
303 		zfcp_dbf_scsi_devreset("wait", sdev, tm_flags, NULL);
304 		zfcp_erp_wait(adapter);
305 		ret = fc_block_rport(rport);
306 		if (ret) {
307 			zfcp_dbf_scsi_devreset("fiof", sdev, tm_flags, NULL);
308 			return ret;
309 		}
310 
311 		if (!(atomic_read(&adapter->status) &
312 		      ZFCP_STATUS_COMMON_RUNNING)) {
313 			zfcp_dbf_scsi_devreset("nres", sdev, tm_flags, NULL);
314 			return SUCCESS;
315 		}
316 	}
317 	if (!fsf_req) {
318 		zfcp_dbf_scsi_devreset("reqf", sdev, tm_flags, NULL);
319 		return FAILED;
320 	}
321 
322 	wait_for_completion(&fsf_req->completion);
323 
324 	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
325 		zfcp_dbf_scsi_devreset("fail", sdev, tm_flags, fsf_req);
326 		retval = FAILED;
327 	} else {
328 		zfcp_dbf_scsi_devreset("okay", sdev, tm_flags, fsf_req);
329 		zfcp_scsi_forget_cmnds(zfcp_sdev, tm_flags);
330 	}
331 
332 	zfcp_fsf_req_free(fsf_req);
333 	return retval;
334 }
335 
336 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
337 {
338 	struct scsi_device *sdev = scpnt->device;
339 
340 	return zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_LUN_RESET);
341 }
342 
343 static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
344 {
345 	struct scsi_target *starget = scsi_target(scpnt->device);
346 	struct fc_rport *rport = starget_to_rport(starget);
347 	struct Scsi_Host *shost = rport_to_shost(rport);
348 	struct scsi_device *sdev = NULL, *tmp_sdev;
349 	struct zfcp_adapter *adapter =
350 		(struct zfcp_adapter *)shost->hostdata[0];
351 	int ret;
352 
353 	shost_for_each_device(tmp_sdev, shost) {
354 		if (tmp_sdev->id == starget->id) {
355 			sdev = tmp_sdev;
356 			break;
357 		}
358 	}
359 	if (!sdev) {
360 		ret = FAILED;
361 		zfcp_dbf_scsi_eh("tr_nosd", adapter, starget->id, ret);
362 		return ret;
363 	}
364 
365 	ret = zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_TGT_RESET);
366 
367 	/* release reference from above shost_for_each_device */
368 	if (sdev)
369 		scsi_device_put(tmp_sdev);
370 
371 	return ret;
372 }
373 
374 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
375 {
376 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
377 	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
378 	int ret = SUCCESS, fc_ret;
379 
380 	if (!(adapter->connection_features & FSF_FEATURE_NPIV_MODE)) {
381 		zfcp_erp_port_forced_reopen_all(adapter, 0, "schrh_p");
382 		zfcp_erp_wait(adapter);
383 	}
384 	zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
385 	zfcp_erp_wait(adapter);
386 	fc_ret = fc_block_scsi_eh(scpnt);
387 	if (fc_ret)
388 		ret = fc_ret;
389 
390 	zfcp_dbf_scsi_eh("schrh_r", adapter, ~0, ret);
391 	return ret;
392 }
393 
394 /**
395  * zfcp_scsi_sysfs_host_reset() - Support scsi_host sysfs attribute host_reset.
396  * @shost: Pointer to Scsi_Host to perform action on.
397  * @reset_type: We support %SCSI_ADAPTER_RESET but not %SCSI_FIRMWARE_RESET.
398  *
399  * Return: 0 on %SCSI_ADAPTER_RESET, -%EOPNOTSUPP otherwise.
400  *
401  * This is similar to zfcp_sysfs_adapter_failed_store().
402  */
403 static int zfcp_scsi_sysfs_host_reset(struct Scsi_Host *shost, int reset_type)
404 {
405 	struct zfcp_adapter *adapter =
406 		(struct zfcp_adapter *)shost->hostdata[0];
407 	int ret = 0;
408 
409 	if (reset_type != SCSI_ADAPTER_RESET) {
410 		ret = -EOPNOTSUPP;
411 		zfcp_dbf_scsi_eh("scshr_n", adapter, ~0, ret);
412 		return ret;
413 	}
414 
415 	zfcp_erp_adapter_reset_sync(adapter, "scshr_y");
416 	return ret;
417 }
418 
419 struct scsi_transport_template *zfcp_scsi_transport_template;
420 
421 static struct scsi_host_template zfcp_scsi_host_template = {
422 	.module			 = THIS_MODULE,
423 	.name			 = "zfcp",
424 	.queuecommand		 = zfcp_scsi_queuecommand,
425 	.eh_timed_out		 = fc_eh_timed_out,
426 	.eh_abort_handler	 = zfcp_scsi_eh_abort_handler,
427 	.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
428 	.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
429 	.eh_host_reset_handler	 = zfcp_scsi_eh_host_reset_handler,
430 	.slave_alloc		 = zfcp_scsi_slave_alloc,
431 	.slave_configure	 = zfcp_scsi_slave_configure,
432 	.slave_destroy		 = zfcp_scsi_slave_destroy,
433 	.change_queue_depth	 = scsi_change_queue_depth,
434 	.host_reset		 = zfcp_scsi_sysfs_host_reset,
435 	.proc_name		 = "zfcp",
436 	.can_queue		 = 4096,
437 	.this_id		 = -1,
438 	.sg_tablesize		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
439 				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2),
440 				   /* GCD, adjusted later */
441 	.max_sectors		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
442 				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2) * 8,
443 				   /* GCD, adjusted later */
444 	/* report size limit per scatter-gather segment */
445 	.max_segment_size	 = ZFCP_QDIO_SBALE_LEN,
446 	.dma_boundary		 = ZFCP_QDIO_SBALE_LEN - 1,
447 	.shost_attrs		 = zfcp_sysfs_shost_attrs,
448 	.sdev_attrs		 = zfcp_sysfs_sdev_attrs,
449 	.track_queue_depth	 = 1,
450 	.supported_mode		 = MODE_INITIATOR,
451 };
452 
453 /**
454  * zfcp_scsi_adapter_register - Register SCSI and FC host with SCSI midlayer
455  * @adapter: The zfcp adapter to register with the SCSI midlayer
456  */
457 int zfcp_scsi_adapter_register(struct zfcp_adapter *adapter)
458 {
459 	struct ccw_dev_id dev_id;
460 
461 	if (adapter->scsi_host)
462 		return 0;
463 
464 	ccw_device_get_id(adapter->ccw_device, &dev_id);
465 	/* register adapter as SCSI host with mid layer of SCSI stack */
466 	adapter->scsi_host = scsi_host_alloc(&zfcp_scsi_host_template,
467 					     sizeof (struct zfcp_adapter *));
468 	if (!adapter->scsi_host) {
469 		dev_err(&adapter->ccw_device->dev,
470 			"Registering the FCP device with the "
471 			"SCSI stack failed\n");
472 		return -EIO;
473 	}
474 
475 	/* tell the SCSI stack some characteristics of this adapter */
476 	adapter->scsi_host->max_id = 511;
477 	adapter->scsi_host->max_lun = 0xFFFFFFFF;
478 	adapter->scsi_host->max_channel = 0;
479 	adapter->scsi_host->unique_id = dev_id.devno;
480 	adapter->scsi_host->max_cmd_len = 16; /* in struct fcp_cmnd */
481 	adapter->scsi_host->transportt = zfcp_scsi_transport_template;
482 
483 	adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
484 
485 	if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
486 		scsi_host_put(adapter->scsi_host);
487 		return -EIO;
488 	}
489 
490 	return 0;
491 }
492 
493 /**
494  * zfcp_scsi_adapter_unregister - Unregister SCSI and FC host from SCSI midlayer
495  * @adapter: The zfcp adapter to unregister.
496  */
497 void zfcp_scsi_adapter_unregister(struct zfcp_adapter *adapter)
498 {
499 	struct Scsi_Host *shost;
500 	struct zfcp_port *port;
501 
502 	shost = adapter->scsi_host;
503 	if (!shost)
504 		return;
505 
506 	read_lock_irq(&adapter->port_list_lock);
507 	list_for_each_entry(port, &adapter->port_list, list)
508 		port->rport = NULL;
509 	read_unlock_irq(&adapter->port_list_lock);
510 
511 	fc_remove_host(shost);
512 	scsi_remove_host(shost);
513 	scsi_host_put(shost);
514 	adapter->scsi_host = NULL;
515 }
516 
517 static struct fc_host_statistics*
518 zfcp_scsi_init_fc_host_stats(struct zfcp_adapter *adapter)
519 {
520 	struct fc_host_statistics *fc_stats;
521 
522 	if (!adapter->fc_stats) {
523 		fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
524 		if (!fc_stats)
525 			return NULL;
526 		adapter->fc_stats = fc_stats; /* freed in adapter_release */
527 	}
528 	memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
529 	return adapter->fc_stats;
530 }
531 
532 static void zfcp_scsi_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
533 					   struct fsf_qtcb_bottom_port *data,
534 					   struct fsf_qtcb_bottom_port *old)
535 {
536 	fc_stats->seconds_since_last_reset =
537 		data->seconds_since_last_reset - old->seconds_since_last_reset;
538 	fc_stats->tx_frames = data->tx_frames - old->tx_frames;
539 	fc_stats->tx_words = data->tx_words - old->tx_words;
540 	fc_stats->rx_frames = data->rx_frames - old->rx_frames;
541 	fc_stats->rx_words = data->rx_words - old->rx_words;
542 	fc_stats->lip_count = data->lip - old->lip;
543 	fc_stats->nos_count = data->nos - old->nos;
544 	fc_stats->error_frames = data->error_frames - old->error_frames;
545 	fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
546 	fc_stats->link_failure_count = data->link_failure - old->link_failure;
547 	fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
548 	fc_stats->loss_of_signal_count =
549 		data->loss_of_signal - old->loss_of_signal;
550 	fc_stats->prim_seq_protocol_err_count =
551 		data->psp_error_counts - old->psp_error_counts;
552 	fc_stats->invalid_tx_word_count =
553 		data->invalid_tx_words - old->invalid_tx_words;
554 	fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
555 	fc_stats->fcp_input_requests =
556 		data->input_requests - old->input_requests;
557 	fc_stats->fcp_output_requests =
558 		data->output_requests - old->output_requests;
559 	fc_stats->fcp_control_requests =
560 		data->control_requests - old->control_requests;
561 	fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
562 	fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
563 }
564 
565 static void zfcp_scsi_set_fc_host_stats(struct fc_host_statistics *fc_stats,
566 					struct fsf_qtcb_bottom_port *data)
567 {
568 	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
569 	fc_stats->tx_frames = data->tx_frames;
570 	fc_stats->tx_words = data->tx_words;
571 	fc_stats->rx_frames = data->rx_frames;
572 	fc_stats->rx_words = data->rx_words;
573 	fc_stats->lip_count = data->lip;
574 	fc_stats->nos_count = data->nos;
575 	fc_stats->error_frames = data->error_frames;
576 	fc_stats->dumped_frames = data->dumped_frames;
577 	fc_stats->link_failure_count = data->link_failure;
578 	fc_stats->loss_of_sync_count = data->loss_of_sync;
579 	fc_stats->loss_of_signal_count = data->loss_of_signal;
580 	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
581 	fc_stats->invalid_tx_word_count = data->invalid_tx_words;
582 	fc_stats->invalid_crc_count = data->invalid_crcs;
583 	fc_stats->fcp_input_requests = data->input_requests;
584 	fc_stats->fcp_output_requests = data->output_requests;
585 	fc_stats->fcp_control_requests = data->control_requests;
586 	fc_stats->fcp_input_megabytes = data->input_mb;
587 	fc_stats->fcp_output_megabytes = data->output_mb;
588 }
589 
590 static struct fc_host_statistics *
591 zfcp_scsi_get_fc_host_stats(struct Scsi_Host *host)
592 {
593 	struct zfcp_adapter *adapter;
594 	struct fc_host_statistics *fc_stats;
595 	struct fsf_qtcb_bottom_port *data;
596 	int ret;
597 
598 	adapter = (struct zfcp_adapter *)host->hostdata[0];
599 	fc_stats = zfcp_scsi_init_fc_host_stats(adapter);
600 	if (!fc_stats)
601 		return NULL;
602 
603 	data = kzalloc(sizeof(*data), GFP_KERNEL);
604 	if (!data)
605 		return NULL;
606 
607 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
608 	if (ret != 0 && ret != -EAGAIN) {
609 		kfree(data);
610 		return NULL;
611 	}
612 
613 	if (adapter->stats_reset &&
614 	    ((jiffies/HZ - adapter->stats_reset) <
615 	     data->seconds_since_last_reset))
616 		zfcp_scsi_adjust_fc_host_stats(fc_stats, data,
617 					       adapter->stats_reset_data);
618 	else
619 		zfcp_scsi_set_fc_host_stats(fc_stats, data);
620 
621 	kfree(data);
622 	return fc_stats;
623 }
624 
625 static void zfcp_scsi_reset_fc_host_stats(struct Scsi_Host *shost)
626 {
627 	struct zfcp_adapter *adapter;
628 	struct fsf_qtcb_bottom_port *data;
629 	int ret;
630 
631 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
632 	data = kzalloc(sizeof(*data), GFP_KERNEL);
633 	if (!data)
634 		return;
635 
636 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
637 	if (ret != 0 && ret != -EAGAIN)
638 		kfree(data);
639 	else {
640 		adapter->stats_reset = jiffies/HZ;
641 		kfree(adapter->stats_reset_data);
642 		adapter->stats_reset_data = data; /* finally freed in
643 						     adapter_release */
644 	}
645 }
646 
647 static void zfcp_scsi_get_host_port_state(struct Scsi_Host *shost)
648 {
649 	struct zfcp_adapter *adapter =
650 		(struct zfcp_adapter *)shost->hostdata[0];
651 	int status = atomic_read(&adapter->status);
652 
653 	if ((status & ZFCP_STATUS_COMMON_RUNNING) &&
654 	    !(status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED))
655 		fc_host_port_state(shost) = FC_PORTSTATE_ONLINE;
656 	else if (status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED)
657 		fc_host_port_state(shost) = FC_PORTSTATE_LINKDOWN;
658 	else if (status & ZFCP_STATUS_COMMON_ERP_FAILED)
659 		fc_host_port_state(shost) = FC_PORTSTATE_ERROR;
660 	else
661 		fc_host_port_state(shost) = FC_PORTSTATE_UNKNOWN;
662 }
663 
664 static void zfcp_scsi_set_rport_dev_loss_tmo(struct fc_rport *rport,
665 					     u32 timeout)
666 {
667 	rport->dev_loss_tmo = timeout;
668 }
669 
670 /**
671  * zfcp_scsi_terminate_rport_io - Terminate all I/O on a rport
672  * @rport: The FC rport where to teminate I/O
673  *
674  * Abort all pending SCSI commands for a port by closing the
675  * port. Using a reopen avoids a conflict with a shutdown
676  * overwriting a reopen. The "forced" ensures that a disappeared port
677  * is not opened again as valid due to the cached plogi data in
678  * non-NPIV mode.
679  */
680 static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
681 {
682 	struct zfcp_port *port;
683 	struct Scsi_Host *shost = rport_to_shost(rport);
684 	struct zfcp_adapter *adapter =
685 		(struct zfcp_adapter *)shost->hostdata[0];
686 
687 	port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
688 
689 	if (port) {
690 		zfcp_erp_port_forced_reopen(port, 0, "sctrpi1");
691 		put_device(&port->dev);
692 	} else {
693 		zfcp_erp_port_forced_no_port_dbf(
694 			"sctrpin", adapter,
695 			rport->port_name /* zfcp_scsi_rport_register */,
696 			rport->port_id /* zfcp_scsi_rport_register */);
697 	}
698 }
699 
700 static void zfcp_scsi_rport_register(struct zfcp_port *port)
701 {
702 	struct fc_rport_identifiers ids;
703 	struct fc_rport *rport;
704 
705 	if (port->rport)
706 		return;
707 
708 	ids.node_name = port->wwnn;
709 	ids.port_name = port->wwpn;
710 	ids.port_id = port->d_id;
711 	ids.roles = FC_RPORT_ROLE_FCP_TARGET;
712 
713 	zfcp_dbf_rec_trig_lock("scpaddy", port->adapter, port, NULL,
714 			       ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD,
715 			       ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD);
716 	rport = fc_remote_port_add(port->adapter->scsi_host, 0, &ids);
717 	if (!rport) {
718 		dev_err(&port->adapter->ccw_device->dev,
719 			"Registering port 0x%016Lx failed\n",
720 			(unsigned long long)port->wwpn);
721 		return;
722 	}
723 
724 	rport->maxframe_size = port->maxframe_size;
725 	rport->supported_classes = port->supported_classes;
726 	port->rport = rport;
727 	port->starget_id = rport->scsi_target_id;
728 
729 	zfcp_unit_queue_scsi_scan(port);
730 }
731 
732 static void zfcp_scsi_rport_block(struct zfcp_port *port)
733 {
734 	struct fc_rport *rport = port->rport;
735 
736 	if (rport) {
737 		zfcp_dbf_rec_trig_lock("scpdely", port->adapter, port, NULL,
738 				       ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL,
739 				       ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL);
740 		fc_remote_port_delete(rport);
741 		port->rport = NULL;
742 	}
743 }
744 
745 void zfcp_scsi_schedule_rport_register(struct zfcp_port *port)
746 {
747 	get_device(&port->dev);
748 	port->rport_task = RPORT_ADD;
749 
750 	if (!queue_work(port->adapter->work_queue, &port->rport_work))
751 		put_device(&port->dev);
752 }
753 
754 void zfcp_scsi_schedule_rport_block(struct zfcp_port *port)
755 {
756 	get_device(&port->dev);
757 	port->rport_task = RPORT_DEL;
758 
759 	if (port->rport && queue_work(port->adapter->work_queue,
760 				      &port->rport_work))
761 		return;
762 
763 	put_device(&port->dev);
764 }
765 
766 void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *adapter)
767 {
768 	unsigned long flags;
769 	struct zfcp_port *port;
770 
771 	read_lock_irqsave(&adapter->port_list_lock, flags);
772 	list_for_each_entry(port, &adapter->port_list, list)
773 		zfcp_scsi_schedule_rport_block(port);
774 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
775 }
776 
777 void zfcp_scsi_rport_work(struct work_struct *work)
778 {
779 	struct zfcp_port *port = container_of(work, struct zfcp_port,
780 					      rport_work);
781 
782 	set_worker_desc("zrp%c-%16llx",
783 			(port->rport_task == RPORT_ADD) ? 'a' : 'd',
784 			port->wwpn); /* < WORKER_DESC_LEN=24 */
785 	while (port->rport_task) {
786 		if (port->rport_task == RPORT_ADD) {
787 			port->rport_task = RPORT_NONE;
788 			zfcp_scsi_rport_register(port);
789 		} else {
790 			port->rport_task = RPORT_NONE;
791 			zfcp_scsi_rport_block(port);
792 		}
793 	}
794 
795 	put_device(&port->dev);
796 }
797 
798 /**
799  * zfcp_scsi_set_prot - Configure DIF/DIX support in scsi_host
800  * @adapter: The adapter where to configure DIF/DIX for the SCSI host
801  */
802 void zfcp_scsi_set_prot(struct zfcp_adapter *adapter)
803 {
804 	unsigned int mask = 0;
805 	unsigned int data_div;
806 	struct Scsi_Host *shost = adapter->scsi_host;
807 
808 	data_div = atomic_read(&adapter->status) &
809 		   ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED;
810 
811 	if ((enable_dif || zfcp_experimental_dix) &&
812 	    adapter->adapter_features & FSF_FEATURE_DIF_PROT_TYPE1)
813 		mask |= SHOST_DIF_TYPE1_PROTECTION;
814 
815 	if (zfcp_experimental_dix && data_div &&
816 	    adapter->adapter_features & FSF_FEATURE_DIX_PROT_TCPIP) {
817 		mask |= SHOST_DIX_TYPE1_PROTECTION;
818 		scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP);
819 		shost->sg_prot_tablesize = adapter->qdio->max_sbale_per_req / 2;
820 		shost->sg_tablesize = adapter->qdio->max_sbale_per_req / 2;
821 		shost->max_sectors = shost->sg_tablesize * 8;
822 	}
823 
824 	scsi_host_set_prot(shost, mask);
825 }
826 
827 /**
828  * zfcp_scsi_dif_sense_error - Report DIF/DIX error as driver sense error
829  * @scmd: The SCSI command to report the error for
830  * @ascq: The ASCQ to put in the sense buffer
831  *
832  * See the error handling in sd_done for the sense codes used here.
833  * Set DID_SOFT_ERROR to retry the request, if possible.
834  */
835 void zfcp_scsi_dif_sense_error(struct scsi_cmnd *scmd, int ascq)
836 {
837 	scsi_build_sense_buffer(1, scmd->sense_buffer,
838 				ILLEGAL_REQUEST, 0x10, ascq);
839 	set_driver_byte(scmd, DRIVER_SENSE);
840 	scmd->result |= SAM_STAT_CHECK_CONDITION;
841 	set_host_byte(scmd, DID_SOFT_ERROR);
842 }
843 
844 struct fc_function_template zfcp_transport_functions = {
845 	.show_starget_port_id = 1,
846 	.show_starget_port_name = 1,
847 	.show_starget_node_name = 1,
848 	.show_rport_supported_classes = 1,
849 	.show_rport_maxframe_size = 1,
850 	.show_rport_dev_loss_tmo = 1,
851 	.show_host_node_name = 1,
852 	.show_host_port_name = 1,
853 	.show_host_permanent_port_name = 1,
854 	.show_host_supported_classes = 1,
855 	.show_host_supported_fc4s = 1,
856 	.show_host_supported_speeds = 1,
857 	.show_host_maxframe_size = 1,
858 	.show_host_serial_number = 1,
859 	.get_fc_host_stats = zfcp_scsi_get_fc_host_stats,
860 	.reset_fc_host_stats = zfcp_scsi_reset_fc_host_stats,
861 	.set_rport_dev_loss_tmo = zfcp_scsi_set_rport_dev_loss_tmo,
862 	.get_host_port_state = zfcp_scsi_get_host_port_state,
863 	.terminate_rport_io = zfcp_scsi_terminate_rport_io,
864 	.show_host_port_state = 1,
865 	.show_host_active_fc4s = 1,
866 	.bsg_request = zfcp_fc_exec_bsg_job,
867 	.bsg_timeout = zfcp_fc_timeout_bsg_job,
868 	/* no functions registered for following dynamic attributes but
869 	   directly set by LLDD */
870 	.show_host_port_type = 1,
871 	.show_host_symbolic_name = 1,
872 	.show_host_speed = 1,
873 	.show_host_port_id = 1,
874 	.dd_bsg_size = sizeof(struct zfcp_fsf_ct_els),
875 };
876