xref: /linux/drivers/s390/scsi/zfcp_fc.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  * zfcp device driver
3  *
4  * Fibre Channel related functions for the zfcp device driver.
5  *
6  * Copyright IBM Corp. 2008, 2010
7  */
8 
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 
12 #include <linux/types.h>
13 #include <linux/slab.h>
14 #include <linux/utsname.h>
15 #include <linux/random.h>
16 #include <scsi/fc/fc_els.h>
17 #include <scsi/libfc.h>
18 #include "zfcp_ext.h"
19 #include "zfcp_fc.h"
20 
21 struct kmem_cache *zfcp_fc_req_cache;
22 
23 static u32 zfcp_fc_rscn_range_mask[] = {
24 	[ELS_ADDR_FMT_PORT]		= 0xFFFFFF,
25 	[ELS_ADDR_FMT_AREA]		= 0xFFFF00,
26 	[ELS_ADDR_FMT_DOM]		= 0xFF0000,
27 	[ELS_ADDR_FMT_FAB]		= 0x000000,
28 };
29 
30 static bool no_auto_port_rescan;
31 module_param_named(no_auto_port_rescan, no_auto_port_rescan, bool, 0600);
32 MODULE_PARM_DESC(no_auto_port_rescan,
33 		 "no automatic port_rescan (default off)");
34 
35 static unsigned int port_scan_backoff = 500;
36 module_param(port_scan_backoff, uint, 0600);
37 MODULE_PARM_DESC(port_scan_backoff,
38 	"upper limit of port scan random backoff in msecs (default 500)");
39 
40 static unsigned int port_scan_ratelimit = 60000;
41 module_param(port_scan_ratelimit, uint, 0600);
42 MODULE_PARM_DESC(port_scan_ratelimit,
43 	"minimum interval between port scans in msecs (default 60000)");
44 
45 unsigned int zfcp_fc_port_scan_backoff(void)
46 {
47 	if (!port_scan_backoff)
48 		return 0;
49 	return get_random_int() % port_scan_backoff;
50 }
51 
52 static void zfcp_fc_port_scan_time(struct zfcp_adapter *adapter)
53 {
54 	unsigned long interval = msecs_to_jiffies(port_scan_ratelimit);
55 	unsigned long backoff = msecs_to_jiffies(zfcp_fc_port_scan_backoff());
56 
57 	adapter->next_port_scan = jiffies + interval + backoff;
58 }
59 
60 static void zfcp_fc_port_scan(struct zfcp_adapter *adapter)
61 {
62 	unsigned long now = jiffies;
63 	unsigned long next = adapter->next_port_scan;
64 	unsigned long delay = 0, max;
65 
66 	/* delay only needed within waiting period */
67 	if (time_before(now, next)) {
68 		delay = next - now;
69 		/* paranoia: never ever delay scans longer than specified */
70 		max = msecs_to_jiffies(port_scan_ratelimit + port_scan_backoff);
71 		delay = min(delay, max);
72 	}
73 
74 	queue_delayed_work(adapter->work_queue, &adapter->scan_work, delay);
75 }
76 
77 void zfcp_fc_conditional_port_scan(struct zfcp_adapter *adapter)
78 {
79 	if (no_auto_port_rescan)
80 		return;
81 
82 	zfcp_fc_port_scan(adapter);
83 }
84 
85 void zfcp_fc_inverse_conditional_port_scan(struct zfcp_adapter *adapter)
86 {
87 	if (!no_auto_port_rescan)
88 		return;
89 
90 	zfcp_fc_port_scan(adapter);
91 }
92 
93 /**
94  * zfcp_fc_post_event - post event to userspace via fc_transport
95  * @work: work struct with enqueued events
96  */
97 void zfcp_fc_post_event(struct work_struct *work)
98 {
99 	struct zfcp_fc_event *event = NULL, *tmp = NULL;
100 	LIST_HEAD(tmp_lh);
101 	struct zfcp_fc_events *events = container_of(work,
102 					struct zfcp_fc_events, work);
103 	struct zfcp_adapter *adapter = container_of(events, struct zfcp_adapter,
104 						events);
105 
106 	spin_lock_bh(&events->list_lock);
107 	list_splice_init(&events->list, &tmp_lh);
108 	spin_unlock_bh(&events->list_lock);
109 
110 	list_for_each_entry_safe(event, tmp, &tmp_lh, list) {
111 		fc_host_post_event(adapter->scsi_host, fc_get_event_number(),
112 				event->code, event->data);
113 		list_del(&event->list);
114 		kfree(event);
115 	}
116 
117 }
118 
119 /**
120  * zfcp_fc_enqueue_event - safely enqueue FC HBA API event from irq context
121  * @adapter: The adapter where to enqueue the event
122  * @event_code: The event code (as defined in fc_host_event_code in
123  *		scsi_transport_fc.h)
124  * @event_data: The event data (e.g. n_port page in case of els)
125  */
126 void zfcp_fc_enqueue_event(struct zfcp_adapter *adapter,
127 			enum fc_host_event_code event_code, u32 event_data)
128 {
129 	struct zfcp_fc_event *event;
130 
131 	event = kmalloc(sizeof(struct zfcp_fc_event), GFP_ATOMIC);
132 	if (!event)
133 		return;
134 
135 	event->code = event_code;
136 	event->data = event_data;
137 
138 	spin_lock(&adapter->events.list_lock);
139 	list_add_tail(&event->list, &adapter->events.list);
140 	spin_unlock(&adapter->events.list_lock);
141 
142 	queue_work(adapter->work_queue, &adapter->events.work);
143 }
144 
145 static int zfcp_fc_wka_port_get(struct zfcp_fc_wka_port *wka_port)
146 {
147 	if (mutex_lock_interruptible(&wka_port->mutex))
148 		return -ERESTARTSYS;
149 
150 	if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
151 	    wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
152 		wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
153 		if (zfcp_fsf_open_wka_port(wka_port))
154 			wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
155 	}
156 
157 	mutex_unlock(&wka_port->mutex);
158 
159 	wait_event(wka_port->completion_wq,
160 		   wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
161 		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
162 
163 	if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
164 		atomic_inc(&wka_port->refcount);
165 		return 0;
166 	}
167 	return -EIO;
168 }
169 
170 static void zfcp_fc_wka_port_offline(struct work_struct *work)
171 {
172 	struct delayed_work *dw = to_delayed_work(work);
173 	struct zfcp_fc_wka_port *wka_port =
174 			container_of(dw, struct zfcp_fc_wka_port, work);
175 
176 	mutex_lock(&wka_port->mutex);
177 	if ((atomic_read(&wka_port->refcount) != 0) ||
178 	    (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
179 		goto out;
180 
181 	wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
182 	if (zfcp_fsf_close_wka_port(wka_port)) {
183 		wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
184 		wake_up(&wka_port->completion_wq);
185 	}
186 out:
187 	mutex_unlock(&wka_port->mutex);
188 }
189 
190 static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
191 {
192 	if (atomic_dec_return(&wka_port->refcount) != 0)
193 		return;
194 	/* wait 10 milliseconds, other reqs might pop in */
195 	schedule_delayed_work(&wka_port->work, HZ / 100);
196 }
197 
198 static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
199 				  struct zfcp_adapter *adapter)
200 {
201 	init_waitqueue_head(&wka_port->completion_wq);
202 
203 	wka_port->adapter = adapter;
204 	wka_port->d_id = d_id;
205 
206 	wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
207 	atomic_set(&wka_port->refcount, 0);
208 	mutex_init(&wka_port->mutex);
209 	INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
210 }
211 
212 static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
213 {
214 	cancel_delayed_work_sync(&wka->work);
215 	mutex_lock(&wka->mutex);
216 	wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
217 	mutex_unlock(&wka->mutex);
218 }
219 
220 void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
221 {
222 	if (!gs)
223 		return;
224 	zfcp_fc_wka_port_force_offline(&gs->ms);
225 	zfcp_fc_wka_port_force_offline(&gs->ts);
226 	zfcp_fc_wka_port_force_offline(&gs->ds);
227 	zfcp_fc_wka_port_force_offline(&gs->as);
228 }
229 
230 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
231 				   struct fc_els_rscn_page *page)
232 {
233 	unsigned long flags;
234 	struct zfcp_adapter *adapter = fsf_req->adapter;
235 	struct zfcp_port *port;
236 
237 	read_lock_irqsave(&adapter->port_list_lock, flags);
238 	list_for_each_entry(port, &adapter->port_list, list) {
239 		if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
240 			zfcp_fc_test_link(port);
241 		if (!port->d_id)
242 			zfcp_erp_port_reopen(port,
243 					     ZFCP_STATUS_COMMON_ERP_FAILED,
244 					     "fcrscn1");
245 	}
246 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
247 }
248 
249 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
250 {
251 	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
252 	struct fc_els_rscn *head;
253 	struct fc_els_rscn_page *page;
254 	u16 i;
255 	u16 no_entries;
256 	unsigned int afmt;
257 
258 	head = (struct fc_els_rscn *) status_buffer->payload.data;
259 	page = (struct fc_els_rscn_page *) head;
260 
261 	/* see FC-FS */
262 	no_entries = head->rscn_plen / sizeof(struct fc_els_rscn_page);
263 
264 	for (i = 1; i < no_entries; i++) {
265 		/* skip head and start with 1st element */
266 		page++;
267 		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
268 		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
269 				       page);
270 		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
271 				      *(u32 *)page);
272 	}
273 	zfcp_fc_conditional_port_scan(fsf_req->adapter);
274 }
275 
276 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
277 {
278 	unsigned long flags;
279 	struct zfcp_adapter *adapter = req->adapter;
280 	struct zfcp_port *port;
281 
282 	read_lock_irqsave(&adapter->port_list_lock, flags);
283 	list_for_each_entry(port, &adapter->port_list, list)
284 		if (port->wwpn == wwpn) {
285 			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
286 			break;
287 		}
288 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
289 }
290 
291 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
292 {
293 	struct fsf_status_read_buffer *status_buffer;
294 	struct fc_els_flogi *plogi;
295 
296 	status_buffer = (struct fsf_status_read_buffer *) req->data;
297 	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
298 	zfcp_fc_incoming_wwpn(req, plogi->fl_wwpn);
299 }
300 
301 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
302 {
303 	struct fsf_status_read_buffer *status_buffer =
304 		(struct fsf_status_read_buffer *)req->data;
305 	struct fc_els_logo *logo =
306 		(struct fc_els_logo *) status_buffer->payload.data;
307 
308 	zfcp_fc_incoming_wwpn(req, logo->fl_n_port_wwn);
309 }
310 
311 /**
312  * zfcp_fc_incoming_els - handle incoming ELS
313  * @fsf_req - request which contains incoming ELS
314  */
315 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
316 {
317 	struct fsf_status_read_buffer *status_buffer =
318 		(struct fsf_status_read_buffer *) fsf_req->data;
319 	unsigned int els_type = status_buffer->payload.data[0];
320 
321 	zfcp_dbf_san_in_els("fciels1", fsf_req);
322 	if (els_type == ELS_PLOGI)
323 		zfcp_fc_incoming_plogi(fsf_req);
324 	else if (els_type == ELS_LOGO)
325 		zfcp_fc_incoming_logo(fsf_req);
326 	else if (els_type == ELS_RSCN)
327 		zfcp_fc_incoming_rscn(fsf_req);
328 }
329 
330 static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
331 {
332 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
333 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
334 
335 	if (ct_els->status)
336 		return;
337 	if (gid_pn_rsp->ct_hdr.ct_cmd != FC_FS_ACC)
338 		return;
339 
340 	/* looks like a valid d_id */
341 	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
342 }
343 
344 static void zfcp_fc_complete(void *data)
345 {
346 	complete(data);
347 }
348 
349 static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
350 {
351 	ct_hdr->ct_rev = FC_CT_REV;
352 	ct_hdr->ct_fs_type = FC_FST_DIR;
353 	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
354 	ct_hdr->ct_cmd = cmd;
355 	ct_hdr->ct_mr_size = mr_size / 4;
356 }
357 
358 static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
359 				     struct zfcp_fc_req *fc_req)
360 {
361 	struct zfcp_adapter *adapter = port->adapter;
362 	DECLARE_COMPLETION_ONSTACK(completion);
363 	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
364 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
365 	int ret;
366 
367 	/* setup parameters for send generic command */
368 	fc_req->ct_els.port = port;
369 	fc_req->ct_els.handler = zfcp_fc_complete;
370 	fc_req->ct_els.handler_data = &completion;
371 	fc_req->ct_els.req = &fc_req->sg_req;
372 	fc_req->ct_els.resp = &fc_req->sg_rsp;
373 	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
374 	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));
375 
376 	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
377 			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
378 	gid_pn_req->gid_pn.fn_wwpn = port->wwpn;
379 
380 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
381 			       adapter->pool.gid_pn_req,
382 			       ZFCP_FC_CTELS_TMO);
383 	if (!ret) {
384 		wait_for_completion(&completion);
385 		zfcp_fc_ns_gid_pn_eval(fc_req);
386 	}
387 	return ret;
388 }
389 
390 /**
391  * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
392  * @port: port where GID_PN request is needed
393  * return: -ENOMEM on error, 0 otherwise
394  */
395 static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
396 {
397 	int ret;
398 	struct zfcp_fc_req *fc_req;
399 	struct zfcp_adapter *adapter = port->adapter;
400 
401 	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
402 	if (!fc_req)
403 		return -ENOMEM;
404 
405 	memset(fc_req, 0, sizeof(*fc_req));
406 
407 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
408 	if (ret)
409 		goto out;
410 
411 	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);
412 
413 	zfcp_fc_wka_port_put(&adapter->gs->ds);
414 out:
415 	mempool_free(fc_req, adapter->pool.gid_pn);
416 	return ret;
417 }
418 
419 void zfcp_fc_port_did_lookup(struct work_struct *work)
420 {
421 	int ret;
422 	struct zfcp_port *port = container_of(work, struct zfcp_port,
423 					      gid_pn_work);
424 
425 	ret = zfcp_fc_ns_gid_pn(port);
426 	if (ret) {
427 		/* could not issue gid_pn for some reason */
428 		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
429 		goto out;
430 	}
431 
432 	if (!port->d_id) {
433 		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
434 		goto out;
435 	}
436 
437 	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
438 out:
439 	put_device(&port->dev);
440 }
441 
442 /**
443  * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
444  * @port: The zfcp_port to lookup the d_id for.
445  */
446 void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
447 {
448 	get_device(&port->dev);
449 	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
450 		put_device(&port->dev);
451 }
452 
453 /**
454  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
455  * @port: zfcp_port structure
456  * @plogi: plogi payload
457  *
458  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
459  */
460 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
461 {
462 	if (plogi->fl_wwpn != port->wwpn) {
463 		port->d_id = 0;
464 		dev_warn(&port->adapter->ccw_device->dev,
465 			 "A port opened with WWPN 0x%016Lx returned data that "
466 			 "identifies it as WWPN 0x%016Lx\n",
467 			 (unsigned long long) port->wwpn,
468 			 (unsigned long long) plogi->fl_wwpn);
469 		return;
470 	}
471 
472 	port->wwnn = plogi->fl_wwnn;
473 	port->maxframe_size = plogi->fl_csp.sp_bb_data;
474 
475 	if (plogi->fl_cssp[0].cp_class & FC_CPC_VALID)
476 		port->supported_classes |= FC_COS_CLASS1;
477 	if (plogi->fl_cssp[1].cp_class & FC_CPC_VALID)
478 		port->supported_classes |= FC_COS_CLASS2;
479 	if (plogi->fl_cssp[2].cp_class & FC_CPC_VALID)
480 		port->supported_classes |= FC_COS_CLASS3;
481 	if (plogi->fl_cssp[3].cp_class & FC_CPC_VALID)
482 		port->supported_classes |= FC_COS_CLASS4;
483 }
484 
485 static void zfcp_fc_adisc_handler(void *data)
486 {
487 	struct zfcp_fc_req *fc_req = data;
488 	struct zfcp_port *port = fc_req->ct_els.port;
489 	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;
490 
491 	if (fc_req->ct_els.status) {
492 		/* request rejected or timed out */
493 		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
494 					    "fcadh_1");
495 		goto out;
496 	}
497 
498 	if (!port->wwnn)
499 		port->wwnn = adisc_resp->adisc_wwnn;
500 
501 	if ((port->wwpn != adisc_resp->adisc_wwpn) ||
502 	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
503 		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
504 				     "fcadh_2");
505 		goto out;
506 	}
507 
508 	/* port is good, unblock rport without going through erp */
509 	zfcp_scsi_schedule_rport_register(port);
510  out:
511 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
512 	put_device(&port->dev);
513 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
514 }
515 
516 static int zfcp_fc_adisc(struct zfcp_port *port)
517 {
518 	struct zfcp_fc_req *fc_req;
519 	struct zfcp_adapter *adapter = port->adapter;
520 	struct Scsi_Host *shost = adapter->scsi_host;
521 	int ret;
522 
523 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
524 	if (!fc_req)
525 		return -ENOMEM;
526 
527 	fc_req->ct_els.port = port;
528 	fc_req->ct_els.req = &fc_req->sg_req;
529 	fc_req->ct_els.resp = &fc_req->sg_rsp;
530 	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
531 		    sizeof(struct fc_els_adisc));
532 	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
533 		    sizeof(struct fc_els_adisc));
534 
535 	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
536 	fc_req->ct_els.handler_data = fc_req;
537 
538 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
539 	   without FC-AL-2 capability, so we don't set it */
540 	fc_req->u.adisc.req.adisc_wwpn = fc_host_port_name(shost);
541 	fc_req->u.adisc.req.adisc_wwnn = fc_host_node_name(shost);
542 	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
543 	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
544 
545 	ret = zfcp_fsf_send_els(adapter, port->d_id, &fc_req->ct_els,
546 				ZFCP_FC_CTELS_TMO);
547 	if (ret)
548 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
549 
550 	return ret;
551 }
552 
553 void zfcp_fc_link_test_work(struct work_struct *work)
554 {
555 	struct zfcp_port *port =
556 		container_of(work, struct zfcp_port, test_link_work);
557 	int retval;
558 
559 	get_device(&port->dev);
560 	port->rport_task = RPORT_DEL;
561 	zfcp_scsi_rport_work(&port->rport_work);
562 
563 	/* only issue one test command at one time per port */
564 	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
565 		goto out;
566 
567 	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
568 
569 	retval = zfcp_fc_adisc(port);
570 	if (retval == 0)
571 		return;
572 
573 	/* send of ADISC was not possible */
574 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
575 	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
576 
577 out:
578 	put_device(&port->dev);
579 }
580 
581 /**
582  * zfcp_fc_test_link - lightweight link test procedure
583  * @port: port to be tested
584  *
585  * Test status of a link to a remote port using the ELS command ADISC.
586  * If there is a problem with the remote port, error recovery steps
587  * will be triggered.
588  */
589 void zfcp_fc_test_link(struct zfcp_port *port)
590 {
591 	get_device(&port->dev);
592 	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
593 		put_device(&port->dev);
594 }
595 
596 static struct zfcp_fc_req *zfcp_alloc_sg_env(int buf_num)
597 {
598 	struct zfcp_fc_req *fc_req;
599 
600 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
601 	if (!fc_req)
602 		return NULL;
603 
604 	if (zfcp_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
605 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
606 		return NULL;
607 	}
608 
609 	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
610 		    sizeof(struct zfcp_fc_gpn_ft_req));
611 
612 	return fc_req;
613 }
614 
615 static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
616 			       struct zfcp_adapter *adapter, int max_bytes)
617 {
618 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
619 	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
620 	DECLARE_COMPLETION_ONSTACK(completion);
621 	int ret;
622 
623 	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
624 	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
625 
626 	ct_els->handler = zfcp_fc_complete;
627 	ct_els->handler_data = &completion;
628 	ct_els->req = &fc_req->sg_req;
629 	ct_els->resp = &fc_req->sg_rsp;
630 
631 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
632 			       ZFCP_FC_CTELS_TMO);
633 	if (!ret)
634 		wait_for_completion(&completion);
635 	return ret;
636 }
637 
638 static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
639 {
640 	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
641 		return;
642 
643 	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
644 
645 	if ((port->supported_classes != 0) ||
646 	    !list_empty(&port->unit_list))
647 		return;
648 
649 	list_move_tail(&port->list, lh);
650 }
651 
652 static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
653 			       struct zfcp_adapter *adapter, int max_entries)
654 {
655 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
656 	struct scatterlist *sg = &fc_req->sg_rsp;
657 	struct fc_ct_hdr *hdr = sg_virt(sg);
658 	struct fc_gpn_ft_resp *acc = sg_virt(sg);
659 	struct zfcp_port *port, *tmp;
660 	unsigned long flags;
661 	LIST_HEAD(remove_lh);
662 	u32 d_id;
663 	int ret = 0, x, last = 0;
664 
665 	if (ct_els->status)
666 		return -EIO;
667 
668 	if (hdr->ct_cmd != FC_FS_ACC) {
669 		if (hdr->ct_reason == FC_BA_RJT_UNABLE)
670 			return -EAGAIN; /* might be a temporary condition */
671 		return -EIO;
672 	}
673 
674 	if (hdr->ct_mr_size) {
675 		dev_warn(&adapter->ccw_device->dev,
676 			 "The name server reported %d words residual data\n",
677 			 hdr->ct_mr_size);
678 		return -E2BIG;
679 	}
680 
681 	/* first entry is the header */
682 	for (x = 1; x < max_entries && !last; x++) {
683 		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
684 			acc++;
685 		else
686 			acc = sg_virt(++sg);
687 
688 		last = acc->fp_flags & FC_NS_FID_LAST;
689 		d_id = ntoh24(acc->fp_fid);
690 
691 		/* don't attach ports with a well known address */
692 		if (d_id >= FC_FID_WELL_KNOWN_BASE)
693 			continue;
694 		/* skip the adapter's port and known remote ports */
695 		if (acc->fp_wwpn == fc_host_port_name(adapter->scsi_host))
696 			continue;
697 
698 		port = zfcp_port_enqueue(adapter, acc->fp_wwpn,
699 					 ZFCP_STATUS_COMMON_NOESC, d_id);
700 		if (!IS_ERR(port))
701 			zfcp_erp_port_reopen(port, 0, "fcegpf1");
702 		else if (PTR_ERR(port) != -EEXIST)
703 			ret = PTR_ERR(port);
704 	}
705 
706 	zfcp_erp_wait(adapter);
707 	write_lock_irqsave(&adapter->port_list_lock, flags);
708 	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
709 		zfcp_fc_validate_port(port, &remove_lh);
710 	write_unlock_irqrestore(&adapter->port_list_lock, flags);
711 
712 	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
713 		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
714 		device_unregister(&port->dev);
715 	}
716 
717 	return ret;
718 }
719 
720 /**
721  * zfcp_fc_scan_ports - scan remote ports and attach new ports
722  * @work: reference to scheduled work
723  */
724 void zfcp_fc_scan_ports(struct work_struct *work)
725 {
726 	struct delayed_work *dw = to_delayed_work(work);
727 	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
728 						    scan_work);
729 	int ret, i;
730 	struct zfcp_fc_req *fc_req;
731 	int chain, max_entries, buf_num, max_bytes;
732 
733 	zfcp_fc_port_scan_time(adapter);
734 
735 	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
736 	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
737 	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
738 	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
739 
740 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
741 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
742 		return;
743 
744 	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
745 		return;
746 
747 	fc_req = zfcp_alloc_sg_env(buf_num);
748 	if (!fc_req)
749 		goto out;
750 
751 	for (i = 0; i < 3; i++) {
752 		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
753 		if (!ret) {
754 			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
755 			if (ret == -EAGAIN)
756 				ssleep(1);
757 			else
758 				break;
759 		}
760 	}
761 	zfcp_sg_free_table(&fc_req->sg_rsp, buf_num);
762 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
763 out:
764 	zfcp_fc_wka_port_put(&adapter->gs->ds);
765 }
766 
767 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
768 			struct zfcp_fc_req *fc_req)
769 {
770 	DECLARE_COMPLETION_ONSTACK(completion);
771 	char devno[] = "DEVNO:";
772 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
773 	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
774 	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
775 	int ret;
776 
777 	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
778 			   FC_SYMBOLIC_NAME_SIZE);
779 	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
780 
781 	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
782 	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
783 
784 	ct_els->handler = zfcp_fc_complete;
785 	ct_els->handler_data = &completion;
786 	ct_els->req = &fc_req->sg_req;
787 	ct_els->resp = &fc_req->sg_rsp;
788 
789 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
790 			       ZFCP_FC_CTELS_TMO);
791 	if (ret)
792 		return ret;
793 
794 	wait_for_completion(&completion);
795 	if (ct_els->status)
796 		return ct_els->status;
797 
798 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
799 	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
800 		snprintf(fc_host_symbolic_name(adapter->scsi_host),
801 			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
802 			 gspn_rsp->gspn.fp_name, devno,
803 			 dev_name(&adapter->ccw_device->dev),
804 			 init_utsname()->nodename);
805 	else
806 		strlcpy(fc_host_symbolic_name(adapter->scsi_host),
807 			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
808 
809 	return 0;
810 }
811 
812 static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
813 			 struct zfcp_fc_req *fc_req)
814 {
815 	DECLARE_COMPLETION_ONSTACK(completion);
816 	struct Scsi_Host *shost = adapter->scsi_host;
817 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
818 	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
819 	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
820 	int ret, len;
821 
822 	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
823 			   FC_SYMBOLIC_NAME_SIZE);
824 	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
825 	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
826 		      FC_SYMBOLIC_NAME_SIZE);
827 	rspn_req->rspn.fr_name_len = len;
828 
829 	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
830 	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
831 
832 	ct_els->handler = zfcp_fc_complete;
833 	ct_els->handler_data = &completion;
834 	ct_els->req = &fc_req->sg_req;
835 	ct_els->resp = &fc_req->sg_rsp;
836 
837 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
838 			       ZFCP_FC_CTELS_TMO);
839 	if (!ret)
840 		wait_for_completion(&completion);
841 }
842 
843 /**
844  * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
845  * @work: ns_up_work of the adapter where to update the symbolic port name
846  *
847  * Retrieve the current symbolic port name that may have been set by
848  * the hardware using the GSPN request and update the fc_host
849  * symbolic_name sysfs attribute. When running in NPIV mode (and hence
850  * the port name is unique for this system), update the symbolic port
851  * name to add Linux specific information and update the FC nameserver
852  * using the RSPN request.
853  */
854 void zfcp_fc_sym_name_update(struct work_struct *work)
855 {
856 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
857 						    ns_up_work);
858 	int ret;
859 	struct zfcp_fc_req *fc_req;
860 
861 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
862 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
863 		return;
864 
865 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
866 	if (!fc_req)
867 		return;
868 
869 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
870 	if (ret)
871 		goto out_free;
872 
873 	ret = zfcp_fc_gspn(adapter, fc_req);
874 	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
875 		goto out_ds_put;
876 
877 	memset(fc_req, 0, sizeof(*fc_req));
878 	zfcp_fc_rspn(adapter, fc_req);
879 
880 out_ds_put:
881 	zfcp_fc_wka_port_put(&adapter->gs->ds);
882 out_free:
883 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
884 }
885 
886 static void zfcp_fc_ct_els_job_handler(void *data)
887 {
888 	struct fc_bsg_job *job = data;
889 	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
890 	struct fc_bsg_reply *jr = job->reply;
891 
892 	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
893 	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
894 	jr->result = zfcp_ct_els->status ? -EIO : 0;
895 	job->job_done(job);
896 }
897 
898 static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct fc_bsg_job *job)
899 {
900 	u32 preamble_word1;
901 	u8 gs_type;
902 	struct zfcp_adapter *adapter;
903 
904 	preamble_word1 = job->request->rqst_data.r_ct.preamble_word1;
905 	gs_type = (preamble_word1 & 0xff000000) >> 24;
906 
907 	adapter = (struct zfcp_adapter *) job->shost->hostdata[0];
908 
909 	switch (gs_type) {
910 	case FC_FST_ALIAS:
911 		return &adapter->gs->as;
912 	case FC_FST_MGMT:
913 		return &adapter->gs->ms;
914 	case FC_FST_TIME:
915 		return &adapter->gs->ts;
916 		break;
917 	case FC_FST_DIR:
918 		return &adapter->gs->ds;
919 		break;
920 	default:
921 		return NULL;
922 	}
923 }
924 
925 static void zfcp_fc_ct_job_handler(void *data)
926 {
927 	struct fc_bsg_job *job = data;
928 	struct zfcp_fc_wka_port *wka_port;
929 
930 	wka_port = zfcp_fc_job_wka_port(job);
931 	zfcp_fc_wka_port_put(wka_port);
932 
933 	zfcp_fc_ct_els_job_handler(data);
934 }
935 
936 static int zfcp_fc_exec_els_job(struct fc_bsg_job *job,
937 				struct zfcp_adapter *adapter)
938 {
939 	struct zfcp_fsf_ct_els *els = job->dd_data;
940 	struct fc_rport *rport = job->rport;
941 	struct zfcp_port *port;
942 	u32 d_id;
943 
944 	if (rport) {
945 		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
946 		if (!port)
947 			return -EINVAL;
948 
949 		d_id = port->d_id;
950 		put_device(&port->dev);
951 	} else
952 		d_id = ntoh24(job->request->rqst_data.h_els.port_id);
953 
954 	els->handler = zfcp_fc_ct_els_job_handler;
955 	return zfcp_fsf_send_els(adapter, d_id, els, job->req->timeout / HZ);
956 }
957 
958 static int zfcp_fc_exec_ct_job(struct fc_bsg_job *job,
959 			       struct zfcp_adapter *adapter)
960 {
961 	int ret;
962 	struct zfcp_fsf_ct_els *ct = job->dd_data;
963 	struct zfcp_fc_wka_port *wka_port;
964 
965 	wka_port = zfcp_fc_job_wka_port(job);
966 	if (!wka_port)
967 		return -EINVAL;
968 
969 	ret = zfcp_fc_wka_port_get(wka_port);
970 	if (ret)
971 		return ret;
972 
973 	ct->handler = zfcp_fc_ct_job_handler;
974 	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->req->timeout / HZ);
975 	if (ret)
976 		zfcp_fc_wka_port_put(wka_port);
977 
978 	return ret;
979 }
980 
981 int zfcp_fc_exec_bsg_job(struct fc_bsg_job *job)
982 {
983 	struct Scsi_Host *shost;
984 	struct zfcp_adapter *adapter;
985 	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
986 
987 	shost = job->rport ? rport_to_shost(job->rport) : job->shost;
988 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
989 
990 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
991 		return -EINVAL;
992 
993 	ct_els->req = job->request_payload.sg_list;
994 	ct_els->resp = job->reply_payload.sg_list;
995 	ct_els->handler_data = job;
996 
997 	switch (job->request->msgcode) {
998 	case FC_BSG_RPT_ELS:
999 	case FC_BSG_HST_ELS_NOLOGIN:
1000 		return zfcp_fc_exec_els_job(job, adapter);
1001 	case FC_BSG_RPT_CT:
1002 	case FC_BSG_HST_CT:
1003 		return zfcp_fc_exec_ct_job(job, adapter);
1004 	default:
1005 		return -EINVAL;
1006 	}
1007 }
1008 
1009 int zfcp_fc_timeout_bsg_job(struct fc_bsg_job *job)
1010 {
1011 	/* hardware tracks timeout, reset bsg timeout to not interfere */
1012 	return -EAGAIN;
1013 }
1014 
1015 int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1016 {
1017 	struct zfcp_fc_wka_ports *wka_ports;
1018 
1019 	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1020 	if (!wka_ports)
1021 		return -ENOMEM;
1022 
1023 	adapter->gs = wka_ports;
1024 	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1025 	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1026 	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1027 	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1028 
1029 	return 0;
1030 }
1031 
1032 void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1033 {
1034 	kfree(adapter->gs);
1035 	adapter->gs = NULL;
1036 }
1037 
1038