xref: /linux/drivers/s390/scsi/zfcp_fc.c (revision 03f7c1d2a49acd30e38789cd809d3300721e9b0e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * zfcp device driver
4  *
5  * Fibre Channel related functions for the zfcp device driver.
6  *
7  * Copyright IBM Corp. 2008, 2017
8  */
9 
10 #define KMSG_COMPONENT "zfcp"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/types.h>
14 #include <linux/slab.h>
15 #include <linux/utsname.h>
16 #include <linux/random.h>
17 #include <linux/bsg-lib.h>
18 #include <scsi/fc/fc_els.h>
19 #include <scsi/libfc.h>
20 #include "zfcp_ext.h"
21 #include "zfcp_fc.h"
22 
23 struct kmem_cache *zfcp_fc_req_cache;
24 
25 static u32 zfcp_fc_rscn_range_mask[] = {
26 	[ELS_ADDR_FMT_PORT]		= 0xFFFFFF,
27 	[ELS_ADDR_FMT_AREA]		= 0xFFFF00,
28 	[ELS_ADDR_FMT_DOM]		= 0xFF0000,
29 	[ELS_ADDR_FMT_FAB]		= 0x000000,
30 };
31 
32 static bool no_auto_port_rescan;
33 module_param(no_auto_port_rescan, bool, 0600);
34 MODULE_PARM_DESC(no_auto_port_rescan,
35 		 "no automatic port_rescan (default off)");
36 
37 static unsigned int port_scan_backoff = 500;
38 module_param(port_scan_backoff, uint, 0600);
39 MODULE_PARM_DESC(port_scan_backoff,
40 	"upper limit of port scan random backoff in msecs (default 500)");
41 
42 static unsigned int port_scan_ratelimit = 60000;
43 module_param(port_scan_ratelimit, uint, 0600);
44 MODULE_PARM_DESC(port_scan_ratelimit,
45 	"minimum interval between port scans in msecs (default 60000)");
46 
47 unsigned int zfcp_fc_port_scan_backoff(void)
48 {
49 	if (!port_scan_backoff)
50 		return 0;
51 	return prandom_u32_max(port_scan_backoff);
52 }
53 
54 static void zfcp_fc_port_scan_time(struct zfcp_adapter *adapter)
55 {
56 	unsigned long interval = msecs_to_jiffies(port_scan_ratelimit);
57 	unsigned long backoff = msecs_to_jiffies(zfcp_fc_port_scan_backoff());
58 
59 	adapter->next_port_scan = jiffies + interval + backoff;
60 }
61 
62 static void zfcp_fc_port_scan(struct zfcp_adapter *adapter)
63 {
64 	unsigned long now = jiffies;
65 	unsigned long next = adapter->next_port_scan;
66 	unsigned long delay = 0, max;
67 
68 	/* delay only needed within waiting period */
69 	if (time_before(now, next)) {
70 		delay = next - now;
71 		/* paranoia: never ever delay scans longer than specified */
72 		max = msecs_to_jiffies(port_scan_ratelimit + port_scan_backoff);
73 		delay = min(delay, max);
74 	}
75 
76 	queue_delayed_work(adapter->work_queue, &adapter->scan_work, delay);
77 }
78 
79 void zfcp_fc_conditional_port_scan(struct zfcp_adapter *adapter)
80 {
81 	if (no_auto_port_rescan)
82 		return;
83 
84 	zfcp_fc_port_scan(adapter);
85 }
86 
87 void zfcp_fc_inverse_conditional_port_scan(struct zfcp_adapter *adapter)
88 {
89 	if (!no_auto_port_rescan)
90 		return;
91 
92 	zfcp_fc_port_scan(adapter);
93 }
94 
95 /**
96  * zfcp_fc_post_event - post event to userspace via fc_transport
97  * @work: work struct with enqueued events
98  */
99 void zfcp_fc_post_event(struct work_struct *work)
100 {
101 	struct zfcp_fc_event *event = NULL, *tmp = NULL;
102 	LIST_HEAD(tmp_lh);
103 	struct zfcp_fc_events *events = container_of(work,
104 					struct zfcp_fc_events, work);
105 	struct zfcp_adapter *adapter = container_of(events, struct zfcp_adapter,
106 						events);
107 
108 	spin_lock_bh(&events->list_lock);
109 	list_splice_init(&events->list, &tmp_lh);
110 	spin_unlock_bh(&events->list_lock);
111 
112 	list_for_each_entry_safe(event, tmp, &tmp_lh, list) {
113 		fc_host_post_event(adapter->scsi_host, fc_get_event_number(),
114 				   event->code, event->data);
115 		list_del(&event->list);
116 		kfree(event);
117 	}
118 }
119 
120 /**
121  * zfcp_fc_enqueue_event - safely enqueue FC HBA API event from irq context
122  * @adapter: The adapter where to enqueue the event
123  * @event_code: The event code (as defined in fc_host_event_code in
124  *		scsi_transport_fc.h)
125  * @event_data: The event data (e.g. n_port page in case of els)
126  */
127 void zfcp_fc_enqueue_event(struct zfcp_adapter *adapter,
128 			   enum fc_host_event_code event_code, u32 event_data)
129 {
130 	struct zfcp_fc_event *event;
131 
132 	event = kmalloc(sizeof(struct zfcp_fc_event), GFP_ATOMIC);
133 	if (!event)
134 		return;
135 
136 	event->code = event_code;
137 	event->data = event_data;
138 
139 	spin_lock(&adapter->events.list_lock);
140 	list_add_tail(&event->list, &adapter->events.list);
141 	spin_unlock(&adapter->events.list_lock);
142 
143 	queue_work(adapter->work_queue, &adapter->events.work);
144 }
145 
146 static int zfcp_fc_wka_port_get(struct zfcp_fc_wka_port *wka_port)
147 {
148 	int ret = -EIO;
149 
150 	if (mutex_lock_interruptible(&wka_port->mutex))
151 		return -ERESTARTSYS;
152 
153 	if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
154 	    wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
155 		wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
156 		if (zfcp_fsf_open_wka_port(wka_port)) {
157 			/* could not even send request, nothing to wait for */
158 			wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
159 			goto out;
160 		}
161 	}
162 
163 	wait_event(wka_port->opened,
164 		   wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
165 		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
166 
167 	if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
168 		atomic_inc(&wka_port->refcount);
169 		ret = 0;
170 		goto out;
171 	}
172 out:
173 	mutex_unlock(&wka_port->mutex);
174 	return ret;
175 }
176 
177 static void zfcp_fc_wka_port_offline(struct work_struct *work)
178 {
179 	struct delayed_work *dw = to_delayed_work(work);
180 	struct zfcp_fc_wka_port *wka_port =
181 			container_of(dw, struct zfcp_fc_wka_port, work);
182 
183 	mutex_lock(&wka_port->mutex);
184 	if ((atomic_read(&wka_port->refcount) != 0) ||
185 	    (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
186 		goto out;
187 
188 	wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
189 	if (zfcp_fsf_close_wka_port(wka_port)) {
190 		/* could not even send request, nothing to wait for */
191 		wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
192 		goto out;
193 	}
194 	wait_event(wka_port->closed,
195 		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
196 out:
197 	mutex_unlock(&wka_port->mutex);
198 }
199 
200 static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
201 {
202 	if (atomic_dec_return(&wka_port->refcount) != 0)
203 		return;
204 	/* wait 10 milliseconds, other reqs might pop in */
205 	queue_delayed_work(wka_port->adapter->work_queue, &wka_port->work,
206 			   msecs_to_jiffies(10));
207 }
208 
209 static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
210 				  struct zfcp_adapter *adapter)
211 {
212 	init_waitqueue_head(&wka_port->opened);
213 	init_waitqueue_head(&wka_port->closed);
214 
215 	wka_port->adapter = adapter;
216 	wka_port->d_id = d_id;
217 
218 	wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
219 	atomic_set(&wka_port->refcount, 0);
220 	mutex_init(&wka_port->mutex);
221 	INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
222 }
223 
224 static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
225 {
226 	cancel_delayed_work_sync(&wka->work);
227 	mutex_lock(&wka->mutex);
228 	wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
229 	mutex_unlock(&wka->mutex);
230 }
231 
232 void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
233 {
234 	if (!gs)
235 		return;
236 	zfcp_fc_wka_port_force_offline(&gs->ms);
237 	zfcp_fc_wka_port_force_offline(&gs->ts);
238 	zfcp_fc_wka_port_force_offline(&gs->ds);
239 	zfcp_fc_wka_port_force_offline(&gs->as);
240 }
241 
242 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
243 				   struct fc_els_rscn_page *page)
244 {
245 	unsigned long flags;
246 	struct zfcp_adapter *adapter = fsf_req->adapter;
247 	struct zfcp_port *port;
248 
249 	read_lock_irqsave(&adapter->port_list_lock, flags);
250 	list_for_each_entry(port, &adapter->port_list, list) {
251 		if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
252 			zfcp_fc_test_link(port);
253 	}
254 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
255 }
256 
257 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
258 {
259 	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
260 	struct zfcp_adapter *adapter = fsf_req->adapter;
261 	struct fc_els_rscn *head;
262 	struct fc_els_rscn_page *page;
263 	u16 i;
264 	u16 no_entries;
265 	unsigned int afmt;
266 
267 	head = (struct fc_els_rscn *) status_buffer->payload.data;
268 	page = (struct fc_els_rscn_page *) head;
269 
270 	/* see FC-FS */
271 	no_entries = be16_to_cpu(head->rscn_plen) /
272 		sizeof(struct fc_els_rscn_page);
273 
274 	if (no_entries > 1) {
275 		/* handle failed ports */
276 		unsigned long flags;
277 		struct zfcp_port *port;
278 
279 		read_lock_irqsave(&adapter->port_list_lock, flags);
280 		list_for_each_entry(port, &adapter->port_list, list) {
281 			if (port->d_id)
282 				continue;
283 			zfcp_erp_port_reopen(port,
284 					     ZFCP_STATUS_COMMON_ERP_FAILED,
285 					     "fcrscn1");
286 		}
287 		read_unlock_irqrestore(&adapter->port_list_lock, flags);
288 	}
289 
290 	for (i = 1; i < no_entries; i++) {
291 		/* skip head and start with 1st element */
292 		page++;
293 		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
294 		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
295 				       page);
296 		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
297 				      *(u32 *)page);
298 	}
299 	zfcp_fc_conditional_port_scan(fsf_req->adapter);
300 }
301 
302 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
303 {
304 	unsigned long flags;
305 	struct zfcp_adapter *adapter = req->adapter;
306 	struct zfcp_port *port;
307 
308 	read_lock_irqsave(&adapter->port_list_lock, flags);
309 	list_for_each_entry(port, &adapter->port_list, list)
310 		if (port->wwpn == wwpn) {
311 			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
312 			break;
313 		}
314 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
315 }
316 
317 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
318 {
319 	struct fsf_status_read_buffer *status_buffer;
320 	struct fc_els_flogi *plogi;
321 
322 	status_buffer = (struct fsf_status_read_buffer *) req->data;
323 	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
324 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(plogi->fl_wwpn));
325 }
326 
327 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
328 {
329 	struct fsf_status_read_buffer *status_buffer =
330 		(struct fsf_status_read_buffer *)req->data;
331 	struct fc_els_logo *logo =
332 		(struct fc_els_logo *) status_buffer->payload.data;
333 
334 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(logo->fl_n_port_wwn));
335 }
336 
337 /**
338  * zfcp_fc_incoming_els - handle incoming ELS
339  * @fsf_req: request which contains incoming ELS
340  */
341 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
342 {
343 	struct fsf_status_read_buffer *status_buffer =
344 		(struct fsf_status_read_buffer *) fsf_req->data;
345 	unsigned int els_type = status_buffer->payload.data[0];
346 
347 	zfcp_dbf_san_in_els("fciels1", fsf_req);
348 	if (els_type == ELS_PLOGI)
349 		zfcp_fc_incoming_plogi(fsf_req);
350 	else if (els_type == ELS_LOGO)
351 		zfcp_fc_incoming_logo(fsf_req);
352 	else if (els_type == ELS_RSCN)
353 		zfcp_fc_incoming_rscn(fsf_req);
354 }
355 
356 static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
357 {
358 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
359 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
360 
361 	if (ct_els->status)
362 		return;
363 	if (gid_pn_rsp->ct_hdr.ct_cmd != cpu_to_be16(FC_FS_ACC))
364 		return;
365 
366 	/* looks like a valid d_id */
367 	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
368 }
369 
370 static void zfcp_fc_complete(void *data)
371 {
372 	complete(data);
373 }
374 
375 static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
376 {
377 	ct_hdr->ct_rev = FC_CT_REV;
378 	ct_hdr->ct_fs_type = FC_FST_DIR;
379 	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
380 	ct_hdr->ct_cmd = cpu_to_be16(cmd);
381 	ct_hdr->ct_mr_size = cpu_to_be16(mr_size / 4);
382 }
383 
384 static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
385 				     struct zfcp_fc_req *fc_req)
386 {
387 	struct zfcp_adapter *adapter = port->adapter;
388 	DECLARE_COMPLETION_ONSTACK(completion);
389 	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
390 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
391 	int ret;
392 
393 	/* setup parameters for send generic command */
394 	fc_req->ct_els.port = port;
395 	fc_req->ct_els.handler = zfcp_fc_complete;
396 	fc_req->ct_els.handler_data = &completion;
397 	fc_req->ct_els.req = &fc_req->sg_req;
398 	fc_req->ct_els.resp = &fc_req->sg_rsp;
399 	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
400 	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));
401 
402 	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
403 			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
404 	gid_pn_req->gid_pn.fn_wwpn = cpu_to_be64(port->wwpn);
405 
406 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
407 			       adapter->pool.gid_pn_req,
408 			       ZFCP_FC_CTELS_TMO);
409 	if (!ret) {
410 		wait_for_completion(&completion);
411 		zfcp_fc_ns_gid_pn_eval(fc_req);
412 	}
413 	return ret;
414 }
415 
416 /**
417  * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
418  * @port: port where GID_PN request is needed
419  * return: -ENOMEM on error, 0 otherwise
420  */
421 static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
422 {
423 	int ret;
424 	struct zfcp_fc_req *fc_req;
425 	struct zfcp_adapter *adapter = port->adapter;
426 
427 	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
428 	if (!fc_req)
429 		return -ENOMEM;
430 
431 	memset(fc_req, 0, sizeof(*fc_req));
432 
433 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
434 	if (ret)
435 		goto out;
436 
437 	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);
438 
439 	zfcp_fc_wka_port_put(&adapter->gs->ds);
440 out:
441 	mempool_free(fc_req, adapter->pool.gid_pn);
442 	return ret;
443 }
444 
445 void zfcp_fc_port_did_lookup(struct work_struct *work)
446 {
447 	int ret;
448 	struct zfcp_port *port = container_of(work, struct zfcp_port,
449 					      gid_pn_work);
450 
451 	set_worker_desc("zgidpn%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
452 	ret = zfcp_fc_ns_gid_pn(port);
453 	if (ret) {
454 		/* could not issue gid_pn for some reason */
455 		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
456 		goto out;
457 	}
458 
459 	if (!port->d_id) {
460 		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
461 		goto out;
462 	}
463 
464 	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
465 out:
466 	put_device(&port->dev);
467 }
468 
469 /**
470  * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
471  * @port: The zfcp_port to lookup the d_id for.
472  */
473 void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
474 {
475 	get_device(&port->dev);
476 	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
477 		put_device(&port->dev);
478 }
479 
480 /**
481  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
482  * @port: zfcp_port structure
483  * @plogi: plogi payload
484  *
485  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
486  */
487 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
488 {
489 	if (be64_to_cpu(plogi->fl_wwpn) != port->wwpn) {
490 		port->d_id = 0;
491 		dev_warn(&port->adapter->ccw_device->dev,
492 			 "A port opened with WWPN 0x%016Lx returned data that "
493 			 "identifies it as WWPN 0x%016Lx\n",
494 			 (unsigned long long) port->wwpn,
495 			 (unsigned long long) be64_to_cpu(plogi->fl_wwpn));
496 		return;
497 	}
498 
499 	port->wwnn = be64_to_cpu(plogi->fl_wwnn);
500 	port->maxframe_size = be16_to_cpu(plogi->fl_csp.sp_bb_data);
501 
502 	if (plogi->fl_cssp[0].cp_class & cpu_to_be16(FC_CPC_VALID))
503 		port->supported_classes |= FC_COS_CLASS1;
504 	if (plogi->fl_cssp[1].cp_class & cpu_to_be16(FC_CPC_VALID))
505 		port->supported_classes |= FC_COS_CLASS2;
506 	if (plogi->fl_cssp[2].cp_class & cpu_to_be16(FC_CPC_VALID))
507 		port->supported_classes |= FC_COS_CLASS3;
508 	if (plogi->fl_cssp[3].cp_class & cpu_to_be16(FC_CPC_VALID))
509 		port->supported_classes |= FC_COS_CLASS4;
510 }
511 
512 static void zfcp_fc_adisc_handler(void *data)
513 {
514 	struct zfcp_fc_req *fc_req = data;
515 	struct zfcp_port *port = fc_req->ct_els.port;
516 	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;
517 
518 	if (fc_req->ct_els.status) {
519 		/* request rejected or timed out */
520 		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
521 					    "fcadh_1");
522 		goto out;
523 	}
524 
525 	if (!port->wwnn)
526 		port->wwnn = be64_to_cpu(adisc_resp->adisc_wwnn);
527 
528 	if ((port->wwpn != be64_to_cpu(adisc_resp->adisc_wwpn)) ||
529 	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
530 		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
531 				     "fcadh_2");
532 		goto out;
533 	}
534 
535 	/* re-init to undo drop from zfcp_fc_adisc() */
536 	port->d_id = ntoh24(adisc_resp->adisc_port_id);
537 	/* port is good, unblock rport without going through erp */
538 	zfcp_scsi_schedule_rport_register(port);
539  out:
540 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
541 	put_device(&port->dev);
542 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
543 }
544 
545 static int zfcp_fc_adisc(struct zfcp_port *port)
546 {
547 	struct zfcp_fc_req *fc_req;
548 	struct zfcp_adapter *adapter = port->adapter;
549 	struct Scsi_Host *shost = adapter->scsi_host;
550 	u32 d_id;
551 	int ret;
552 
553 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
554 	if (!fc_req)
555 		return -ENOMEM;
556 
557 	fc_req->ct_els.port = port;
558 	fc_req->ct_els.req = &fc_req->sg_req;
559 	fc_req->ct_els.resp = &fc_req->sg_rsp;
560 	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
561 		    sizeof(struct fc_els_adisc));
562 	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
563 		    sizeof(struct fc_els_adisc));
564 
565 	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
566 	fc_req->ct_els.handler_data = fc_req;
567 
568 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
569 	   without FC-AL-2 capability, so we don't set it */
570 	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
571 	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
572 	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
573 	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
574 
575 	d_id = port->d_id; /* remember as destination for send els below */
576 	/*
577 	 * Force fresh GID_PN lookup on next port recovery.
578 	 * Must happen after request setup and before sending request,
579 	 * to prevent race with port->d_id re-init in zfcp_fc_adisc_handler().
580 	 */
581 	port->d_id = 0;
582 
583 	ret = zfcp_fsf_send_els(adapter, d_id, &fc_req->ct_els,
584 				ZFCP_FC_CTELS_TMO);
585 	if (ret)
586 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
587 
588 	return ret;
589 }
590 
591 void zfcp_fc_link_test_work(struct work_struct *work)
592 {
593 	struct zfcp_port *port =
594 		container_of(work, struct zfcp_port, test_link_work);
595 	int retval;
596 
597 	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
598 	get_device(&port->dev);
599 	port->rport_task = RPORT_DEL;
600 	zfcp_scsi_rport_work(&port->rport_work);
601 
602 	/* only issue one test command at one time per port */
603 	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
604 		goto out;
605 
606 	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
607 
608 	retval = zfcp_fc_adisc(port);
609 	if (retval == 0)
610 		return;
611 
612 	/* send of ADISC was not possible */
613 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
614 	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
615 
616 out:
617 	put_device(&port->dev);
618 }
619 
620 /**
621  * zfcp_fc_test_link - lightweight link test procedure
622  * @port: port to be tested
623  *
624  * Test status of a link to a remote port using the ELS command ADISC.
625  * If there is a problem with the remote port, error recovery steps
626  * will be triggered.
627  */
628 void zfcp_fc_test_link(struct zfcp_port *port)
629 {
630 	get_device(&port->dev);
631 	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
632 		put_device(&port->dev);
633 }
634 
635 /**
636  * zfcp_fc_sg_free_table - free memory used by scatterlists
637  * @sg: pointer to scatterlist
638  * @count: number of scatterlist which are to be free'ed
639  * the scatterlist are expected to reference pages always
640  */
641 static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
642 {
643 	int i;
644 
645 	for (i = 0; i < count; i++, sg = sg_next(sg))
646 		if (sg)
647 			free_page((unsigned long) sg_virt(sg));
648 		else
649 			break;
650 }
651 
652 /**
653  * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
654  * @sg: pointer to struct scatterlist
655  * @count: number of scatterlists which should be assigned with buffers
656  * of size page
657  *
658  * Returns: 0 on success, -ENOMEM otherwise
659  */
660 static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
661 {
662 	void *addr;
663 	int i;
664 
665 	sg_init_table(sg, count);
666 	for (i = 0; i < count; i++, sg = sg_next(sg)) {
667 		addr = (void *) get_zeroed_page(GFP_KERNEL);
668 		if (!addr) {
669 			zfcp_fc_sg_free_table(sg, i);
670 			return -ENOMEM;
671 		}
672 		sg_set_buf(sg, addr, PAGE_SIZE);
673 	}
674 	return 0;
675 }
676 
677 static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
678 {
679 	struct zfcp_fc_req *fc_req;
680 
681 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
682 	if (!fc_req)
683 		return NULL;
684 
685 	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
686 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
687 		return NULL;
688 	}
689 
690 	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
691 		    sizeof(struct zfcp_fc_gpn_ft_req));
692 
693 	return fc_req;
694 }
695 
696 static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
697 			       struct zfcp_adapter *adapter, int max_bytes)
698 {
699 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
700 	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
701 	DECLARE_COMPLETION_ONSTACK(completion);
702 	int ret;
703 
704 	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
705 	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
706 
707 	ct_els->handler = zfcp_fc_complete;
708 	ct_els->handler_data = &completion;
709 	ct_els->req = &fc_req->sg_req;
710 	ct_els->resp = &fc_req->sg_rsp;
711 
712 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
713 			       ZFCP_FC_CTELS_TMO);
714 	if (!ret)
715 		wait_for_completion(&completion);
716 	return ret;
717 }
718 
719 static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
720 {
721 	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
722 		return;
723 
724 	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
725 
726 	if ((port->supported_classes != 0) ||
727 	    !list_empty(&port->unit_list))
728 		return;
729 
730 	list_move_tail(&port->list, lh);
731 }
732 
733 static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
734 			       struct zfcp_adapter *adapter, int max_entries)
735 {
736 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
737 	struct scatterlist *sg = &fc_req->sg_rsp;
738 	struct fc_ct_hdr *hdr = sg_virt(sg);
739 	struct fc_gpn_ft_resp *acc = sg_virt(sg);
740 	struct zfcp_port *port, *tmp;
741 	unsigned long flags;
742 	LIST_HEAD(remove_lh);
743 	u32 d_id;
744 	int ret = 0, x, last = 0;
745 
746 	if (ct_els->status)
747 		return -EIO;
748 
749 	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
750 		if (hdr->ct_reason == FC_FS_RJT_UNABL)
751 			return -EAGAIN; /* might be a temporary condition */
752 		return -EIO;
753 	}
754 
755 	if (hdr->ct_mr_size) {
756 		dev_warn(&adapter->ccw_device->dev,
757 			 "The name server reported %d words residual data\n",
758 			 hdr->ct_mr_size);
759 		return -E2BIG;
760 	}
761 
762 	/* first entry is the header */
763 	for (x = 1; x < max_entries && !last; x++) {
764 		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
765 			acc++;
766 		else
767 			acc = sg_virt(++sg);
768 
769 		last = acc->fp_flags & FC_NS_FID_LAST;
770 		d_id = ntoh24(acc->fp_fid);
771 
772 		/* don't attach ports with a well known address */
773 		if (d_id >= FC_FID_WELL_KNOWN_BASE)
774 			continue;
775 		/* skip the adapter's port and known remote ports */
776 		if (be64_to_cpu(acc->fp_wwpn) ==
777 		    fc_host_port_name(adapter->scsi_host))
778 			continue;
779 
780 		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
781 					 ZFCP_STATUS_COMMON_NOESC, d_id);
782 		if (!IS_ERR(port))
783 			zfcp_erp_port_reopen(port, 0, "fcegpf1");
784 		else if (PTR_ERR(port) != -EEXIST)
785 			ret = PTR_ERR(port);
786 	}
787 
788 	zfcp_erp_wait(adapter);
789 	write_lock_irqsave(&adapter->port_list_lock, flags);
790 	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
791 		zfcp_fc_validate_port(port, &remove_lh);
792 	write_unlock_irqrestore(&adapter->port_list_lock, flags);
793 
794 	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
795 		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
796 		device_unregister(&port->dev);
797 	}
798 
799 	return ret;
800 }
801 
802 /**
803  * zfcp_fc_scan_ports - scan remote ports and attach new ports
804  * @work: reference to scheduled work
805  */
806 void zfcp_fc_scan_ports(struct work_struct *work)
807 {
808 	struct delayed_work *dw = to_delayed_work(work);
809 	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
810 						    scan_work);
811 	int ret, i;
812 	struct zfcp_fc_req *fc_req;
813 	int chain, max_entries, buf_num, max_bytes;
814 
815 	zfcp_fc_port_scan_time(adapter);
816 
817 	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
818 	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
819 	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
820 	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
821 
822 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
823 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
824 		return;
825 
826 	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
827 		return;
828 
829 	fc_req = zfcp_fc_alloc_sg_env(buf_num);
830 	if (!fc_req)
831 		goto out;
832 
833 	for (i = 0; i < 3; i++) {
834 		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
835 		if (!ret) {
836 			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
837 			if (ret == -EAGAIN)
838 				ssleep(1);
839 			else
840 				break;
841 		}
842 	}
843 	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
844 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
845 out:
846 	zfcp_fc_wka_port_put(&adapter->gs->ds);
847 }
848 
849 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
850 			struct zfcp_fc_req *fc_req)
851 {
852 	DECLARE_COMPLETION_ONSTACK(completion);
853 	char devno[] = "DEVNO:";
854 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
855 	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
856 	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
857 	int ret;
858 
859 	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
860 			   FC_SYMBOLIC_NAME_SIZE);
861 	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
862 
863 	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
864 	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
865 
866 	ct_els->handler = zfcp_fc_complete;
867 	ct_els->handler_data = &completion;
868 	ct_els->req = &fc_req->sg_req;
869 	ct_els->resp = &fc_req->sg_rsp;
870 
871 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
872 			       ZFCP_FC_CTELS_TMO);
873 	if (ret)
874 		return ret;
875 
876 	wait_for_completion(&completion);
877 	if (ct_els->status)
878 		return ct_els->status;
879 
880 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
881 	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
882 		snprintf(fc_host_symbolic_name(adapter->scsi_host),
883 			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
884 			 gspn_rsp->gspn.fp_name, devno,
885 			 dev_name(&adapter->ccw_device->dev),
886 			 init_utsname()->nodename);
887 	else
888 		strscpy(fc_host_symbolic_name(adapter->scsi_host),
889 			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
890 
891 	return 0;
892 }
893 
894 static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
895 			 struct zfcp_fc_req *fc_req)
896 {
897 	DECLARE_COMPLETION_ONSTACK(completion);
898 	struct Scsi_Host *shost = adapter->scsi_host;
899 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
900 	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
901 	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
902 	int ret, len;
903 
904 	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
905 			   FC_SYMBOLIC_NAME_SIZE);
906 	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
907 	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
908 		      FC_SYMBOLIC_NAME_SIZE);
909 	rspn_req->rspn.fr_name_len = len;
910 
911 	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
912 	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
913 
914 	ct_els->handler = zfcp_fc_complete;
915 	ct_els->handler_data = &completion;
916 	ct_els->req = &fc_req->sg_req;
917 	ct_els->resp = &fc_req->sg_rsp;
918 
919 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
920 			       ZFCP_FC_CTELS_TMO);
921 	if (!ret)
922 		wait_for_completion(&completion);
923 }
924 
925 /**
926  * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
927  * @work: ns_up_work of the adapter where to update the symbolic port name
928  *
929  * Retrieve the current symbolic port name that may have been set by
930  * the hardware using the GSPN request and update the fc_host
931  * symbolic_name sysfs attribute. When running in NPIV mode (and hence
932  * the port name is unique for this system), update the symbolic port
933  * name to add Linux specific information and update the FC nameserver
934  * using the RSPN request.
935  */
936 void zfcp_fc_sym_name_update(struct work_struct *work)
937 {
938 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
939 						    ns_up_work);
940 	int ret;
941 	struct zfcp_fc_req *fc_req;
942 
943 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
944 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
945 		return;
946 
947 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
948 	if (!fc_req)
949 		return;
950 
951 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
952 	if (ret)
953 		goto out_free;
954 
955 	ret = zfcp_fc_gspn(adapter, fc_req);
956 	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
957 		goto out_ds_put;
958 
959 	memset(fc_req, 0, sizeof(*fc_req));
960 	zfcp_fc_rspn(adapter, fc_req);
961 
962 out_ds_put:
963 	zfcp_fc_wka_port_put(&adapter->gs->ds);
964 out_free:
965 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
966 }
967 
968 static void zfcp_fc_ct_els_job_handler(void *data)
969 {
970 	struct bsg_job *job = data;
971 	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
972 	struct fc_bsg_reply *jr = job->reply;
973 
974 	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
975 	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
976 	jr->result = zfcp_ct_els->status ? -EIO : 0;
977 	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
978 }
979 
980 static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
981 {
982 	u32 preamble_word1;
983 	u8 gs_type;
984 	struct zfcp_adapter *adapter;
985 	struct fc_bsg_request *bsg_request = job->request;
986 	struct fc_rport *rport = fc_bsg_to_rport(job);
987 	struct Scsi_Host *shost;
988 
989 	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
990 	gs_type = (preamble_word1 & 0xff000000) >> 24;
991 
992 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
993 	adapter = (struct zfcp_adapter *) shost->hostdata[0];
994 
995 	switch (gs_type) {
996 	case FC_FST_ALIAS:
997 		return &adapter->gs->as;
998 	case FC_FST_MGMT:
999 		return &adapter->gs->ms;
1000 	case FC_FST_TIME:
1001 		return &adapter->gs->ts;
1002 		break;
1003 	case FC_FST_DIR:
1004 		return &adapter->gs->ds;
1005 		break;
1006 	default:
1007 		return NULL;
1008 	}
1009 }
1010 
1011 static void zfcp_fc_ct_job_handler(void *data)
1012 {
1013 	struct bsg_job *job = data;
1014 	struct zfcp_fc_wka_port *wka_port;
1015 
1016 	wka_port = zfcp_fc_job_wka_port(job);
1017 	zfcp_fc_wka_port_put(wka_port);
1018 
1019 	zfcp_fc_ct_els_job_handler(data);
1020 }
1021 
1022 static int zfcp_fc_exec_els_job(struct bsg_job *job,
1023 				struct zfcp_adapter *adapter)
1024 {
1025 	struct zfcp_fsf_ct_els *els = job->dd_data;
1026 	struct fc_rport *rport = fc_bsg_to_rport(job);
1027 	struct fc_bsg_request *bsg_request = job->request;
1028 	struct zfcp_port *port;
1029 	u32 d_id;
1030 
1031 	if (rport) {
1032 		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
1033 		if (!port)
1034 			return -EINVAL;
1035 
1036 		d_id = port->d_id;
1037 		put_device(&port->dev);
1038 	} else
1039 		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);
1040 
1041 	els->handler = zfcp_fc_ct_els_job_handler;
1042 	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
1043 }
1044 
1045 static int zfcp_fc_exec_ct_job(struct bsg_job *job,
1046 			       struct zfcp_adapter *adapter)
1047 {
1048 	int ret;
1049 	struct zfcp_fsf_ct_els *ct = job->dd_data;
1050 	struct zfcp_fc_wka_port *wka_port;
1051 
1052 	wka_port = zfcp_fc_job_wka_port(job);
1053 	if (!wka_port)
1054 		return -EINVAL;
1055 
1056 	ret = zfcp_fc_wka_port_get(wka_port);
1057 	if (ret)
1058 		return ret;
1059 
1060 	ct->handler = zfcp_fc_ct_job_handler;
1061 	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
1062 	if (ret)
1063 		zfcp_fc_wka_port_put(wka_port);
1064 
1065 	return ret;
1066 }
1067 
1068 int zfcp_fc_exec_bsg_job(struct bsg_job *job)
1069 {
1070 	struct Scsi_Host *shost;
1071 	struct zfcp_adapter *adapter;
1072 	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
1073 	struct fc_bsg_request *bsg_request = job->request;
1074 	struct fc_rport *rport = fc_bsg_to_rport(job);
1075 
1076 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1077 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
1078 
1079 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
1080 		return -EINVAL;
1081 
1082 	ct_els->req = job->request_payload.sg_list;
1083 	ct_els->resp = job->reply_payload.sg_list;
1084 	ct_els->handler_data = job;
1085 
1086 	switch (bsg_request->msgcode) {
1087 	case FC_BSG_RPT_ELS:
1088 	case FC_BSG_HST_ELS_NOLOGIN:
1089 		return zfcp_fc_exec_els_job(job, adapter);
1090 	case FC_BSG_RPT_CT:
1091 	case FC_BSG_HST_CT:
1092 		return zfcp_fc_exec_ct_job(job, adapter);
1093 	default:
1094 		return -EINVAL;
1095 	}
1096 }
1097 
1098 int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
1099 {
1100 	/* hardware tracks timeout, reset bsg timeout to not interfere */
1101 	return -EAGAIN;
1102 }
1103 
1104 int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1105 {
1106 	struct zfcp_fc_wka_ports *wka_ports;
1107 
1108 	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1109 	if (!wka_ports)
1110 		return -ENOMEM;
1111 
1112 	adapter->gs = wka_ports;
1113 	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1114 	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1115 	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1116 	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1117 
1118 	return 0;
1119 }
1120 
1121 void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1122 {
1123 	kfree(adapter->gs);
1124 	adapter->gs = NULL;
1125 }
1126 
1127