xref: /linux/drivers/s390/scsi/zfcp_fc.c (revision 3f0a50f345f78183f6e9b39c2f45ca5dcaa511ca)
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 	if (mutex_lock_interruptible(&wka_port->mutex))
149 		return -ERESTARTSYS;
150 
151 	if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
152 	    wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
153 		wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
154 		if (zfcp_fsf_open_wka_port(wka_port))
155 			wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
156 	}
157 
158 	mutex_unlock(&wka_port->mutex);
159 
160 	wait_event(wka_port->completion_wq,
161 		   wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
162 		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
163 
164 	if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
165 		atomic_inc(&wka_port->refcount);
166 		return 0;
167 	}
168 	return -EIO;
169 }
170 
171 static void zfcp_fc_wka_port_offline(struct work_struct *work)
172 {
173 	struct delayed_work *dw = to_delayed_work(work);
174 	struct zfcp_fc_wka_port *wka_port =
175 			container_of(dw, struct zfcp_fc_wka_port, work);
176 
177 	mutex_lock(&wka_port->mutex);
178 	if ((atomic_read(&wka_port->refcount) != 0) ||
179 	    (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
180 		goto out;
181 
182 	wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
183 	if (zfcp_fsf_close_wka_port(wka_port)) {
184 		wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
185 		wake_up(&wka_port->completion_wq);
186 	}
187 out:
188 	mutex_unlock(&wka_port->mutex);
189 }
190 
191 static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
192 {
193 	if (atomic_dec_return(&wka_port->refcount) != 0)
194 		return;
195 	/* wait 10 milliseconds, other reqs might pop in */
196 	schedule_delayed_work(&wka_port->work, HZ / 100);
197 }
198 
199 static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
200 				  struct zfcp_adapter *adapter)
201 {
202 	init_waitqueue_head(&wka_port->completion_wq);
203 
204 	wka_port->adapter = adapter;
205 	wka_port->d_id = d_id;
206 
207 	wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
208 	atomic_set(&wka_port->refcount, 0);
209 	mutex_init(&wka_port->mutex);
210 	INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
211 }
212 
213 static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
214 {
215 	cancel_delayed_work_sync(&wka->work);
216 	mutex_lock(&wka->mutex);
217 	wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
218 	mutex_unlock(&wka->mutex);
219 }
220 
221 void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
222 {
223 	if (!gs)
224 		return;
225 	zfcp_fc_wka_port_force_offline(&gs->ms);
226 	zfcp_fc_wka_port_force_offline(&gs->ts);
227 	zfcp_fc_wka_port_force_offline(&gs->ds);
228 	zfcp_fc_wka_port_force_offline(&gs->as);
229 }
230 
231 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
232 				   struct fc_els_rscn_page *page)
233 {
234 	unsigned long flags;
235 	struct zfcp_adapter *adapter = fsf_req->adapter;
236 	struct zfcp_port *port;
237 
238 	read_lock_irqsave(&adapter->port_list_lock, flags);
239 	list_for_each_entry(port, &adapter->port_list, list) {
240 		if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
241 			zfcp_fc_test_link(port);
242 	}
243 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
244 }
245 
246 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
247 {
248 	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
249 	struct zfcp_adapter *adapter = fsf_req->adapter;
250 	struct fc_els_rscn *head;
251 	struct fc_els_rscn_page *page;
252 	u16 i;
253 	u16 no_entries;
254 	unsigned int afmt;
255 
256 	head = (struct fc_els_rscn *) status_buffer->payload.data;
257 	page = (struct fc_els_rscn_page *) head;
258 
259 	/* see FC-FS */
260 	no_entries = be16_to_cpu(head->rscn_plen) /
261 		sizeof(struct fc_els_rscn_page);
262 
263 	if (no_entries > 1) {
264 		/* handle failed ports */
265 		unsigned long flags;
266 		struct zfcp_port *port;
267 
268 		read_lock_irqsave(&adapter->port_list_lock, flags);
269 		list_for_each_entry(port, &adapter->port_list, list) {
270 			if (port->d_id)
271 				continue;
272 			zfcp_erp_port_reopen(port,
273 					     ZFCP_STATUS_COMMON_ERP_FAILED,
274 					     "fcrscn1");
275 		}
276 		read_unlock_irqrestore(&adapter->port_list_lock, flags);
277 	}
278 
279 	for (i = 1; i < no_entries; i++) {
280 		/* skip head and start with 1st element */
281 		page++;
282 		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
283 		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
284 				       page);
285 		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
286 				      *(u32 *)page);
287 	}
288 	zfcp_fc_conditional_port_scan(fsf_req->adapter);
289 }
290 
291 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
292 {
293 	unsigned long flags;
294 	struct zfcp_adapter *adapter = req->adapter;
295 	struct zfcp_port *port;
296 
297 	read_lock_irqsave(&adapter->port_list_lock, flags);
298 	list_for_each_entry(port, &adapter->port_list, list)
299 		if (port->wwpn == wwpn) {
300 			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
301 			break;
302 		}
303 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
304 }
305 
306 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
307 {
308 	struct fsf_status_read_buffer *status_buffer;
309 	struct fc_els_flogi *plogi;
310 
311 	status_buffer = (struct fsf_status_read_buffer *) req->data;
312 	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
313 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(plogi->fl_wwpn));
314 }
315 
316 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
317 {
318 	struct fsf_status_read_buffer *status_buffer =
319 		(struct fsf_status_read_buffer *)req->data;
320 	struct fc_els_logo *logo =
321 		(struct fc_els_logo *) status_buffer->payload.data;
322 
323 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(logo->fl_n_port_wwn));
324 }
325 
326 /**
327  * zfcp_fc_incoming_els - handle incoming ELS
328  * @fsf_req: request which contains incoming ELS
329  */
330 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
331 {
332 	struct fsf_status_read_buffer *status_buffer =
333 		(struct fsf_status_read_buffer *) fsf_req->data;
334 	unsigned int els_type = status_buffer->payload.data[0];
335 
336 	zfcp_dbf_san_in_els("fciels1", fsf_req);
337 	if (els_type == ELS_PLOGI)
338 		zfcp_fc_incoming_plogi(fsf_req);
339 	else if (els_type == ELS_LOGO)
340 		zfcp_fc_incoming_logo(fsf_req);
341 	else if (els_type == ELS_RSCN)
342 		zfcp_fc_incoming_rscn(fsf_req);
343 }
344 
345 static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
346 {
347 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
348 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
349 
350 	if (ct_els->status)
351 		return;
352 	if (gid_pn_rsp->ct_hdr.ct_cmd != cpu_to_be16(FC_FS_ACC))
353 		return;
354 
355 	/* looks like a valid d_id */
356 	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
357 }
358 
359 static void zfcp_fc_complete(void *data)
360 {
361 	complete(data);
362 }
363 
364 static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
365 {
366 	ct_hdr->ct_rev = FC_CT_REV;
367 	ct_hdr->ct_fs_type = FC_FST_DIR;
368 	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
369 	ct_hdr->ct_cmd = cpu_to_be16(cmd);
370 	ct_hdr->ct_mr_size = cpu_to_be16(mr_size / 4);
371 }
372 
373 static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
374 				     struct zfcp_fc_req *fc_req)
375 {
376 	struct zfcp_adapter *adapter = port->adapter;
377 	DECLARE_COMPLETION_ONSTACK(completion);
378 	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
379 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
380 	int ret;
381 
382 	/* setup parameters for send generic command */
383 	fc_req->ct_els.port = port;
384 	fc_req->ct_els.handler = zfcp_fc_complete;
385 	fc_req->ct_els.handler_data = &completion;
386 	fc_req->ct_els.req = &fc_req->sg_req;
387 	fc_req->ct_els.resp = &fc_req->sg_rsp;
388 	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
389 	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));
390 
391 	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
392 			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
393 	gid_pn_req->gid_pn.fn_wwpn = cpu_to_be64(port->wwpn);
394 
395 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
396 			       adapter->pool.gid_pn_req,
397 			       ZFCP_FC_CTELS_TMO);
398 	if (!ret) {
399 		wait_for_completion(&completion);
400 		zfcp_fc_ns_gid_pn_eval(fc_req);
401 	}
402 	return ret;
403 }
404 
405 /**
406  * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
407  * @port: port where GID_PN request is needed
408  * return: -ENOMEM on error, 0 otherwise
409  */
410 static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
411 {
412 	int ret;
413 	struct zfcp_fc_req *fc_req;
414 	struct zfcp_adapter *adapter = port->adapter;
415 
416 	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
417 	if (!fc_req)
418 		return -ENOMEM;
419 
420 	memset(fc_req, 0, sizeof(*fc_req));
421 
422 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
423 	if (ret)
424 		goto out;
425 
426 	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);
427 
428 	zfcp_fc_wka_port_put(&adapter->gs->ds);
429 out:
430 	mempool_free(fc_req, adapter->pool.gid_pn);
431 	return ret;
432 }
433 
434 void zfcp_fc_port_did_lookup(struct work_struct *work)
435 {
436 	int ret;
437 	struct zfcp_port *port = container_of(work, struct zfcp_port,
438 					      gid_pn_work);
439 
440 	set_worker_desc("zgidpn%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
441 	ret = zfcp_fc_ns_gid_pn(port);
442 	if (ret) {
443 		/* could not issue gid_pn for some reason */
444 		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
445 		goto out;
446 	}
447 
448 	if (!port->d_id) {
449 		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
450 		goto out;
451 	}
452 
453 	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
454 out:
455 	put_device(&port->dev);
456 }
457 
458 /**
459  * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
460  * @port: The zfcp_port to lookup the d_id for.
461  */
462 void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
463 {
464 	get_device(&port->dev);
465 	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
466 		put_device(&port->dev);
467 }
468 
469 /**
470  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
471  * @port: zfcp_port structure
472  * @plogi: plogi payload
473  *
474  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
475  */
476 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
477 {
478 	if (be64_to_cpu(plogi->fl_wwpn) != port->wwpn) {
479 		port->d_id = 0;
480 		dev_warn(&port->adapter->ccw_device->dev,
481 			 "A port opened with WWPN 0x%016Lx returned data that "
482 			 "identifies it as WWPN 0x%016Lx\n",
483 			 (unsigned long long) port->wwpn,
484 			 (unsigned long long) be64_to_cpu(plogi->fl_wwpn));
485 		return;
486 	}
487 
488 	port->wwnn = be64_to_cpu(plogi->fl_wwnn);
489 	port->maxframe_size = be16_to_cpu(plogi->fl_csp.sp_bb_data);
490 
491 	if (plogi->fl_cssp[0].cp_class & cpu_to_be16(FC_CPC_VALID))
492 		port->supported_classes |= FC_COS_CLASS1;
493 	if (plogi->fl_cssp[1].cp_class & cpu_to_be16(FC_CPC_VALID))
494 		port->supported_classes |= FC_COS_CLASS2;
495 	if (plogi->fl_cssp[2].cp_class & cpu_to_be16(FC_CPC_VALID))
496 		port->supported_classes |= FC_COS_CLASS3;
497 	if (plogi->fl_cssp[3].cp_class & cpu_to_be16(FC_CPC_VALID))
498 		port->supported_classes |= FC_COS_CLASS4;
499 }
500 
501 static void zfcp_fc_adisc_handler(void *data)
502 {
503 	struct zfcp_fc_req *fc_req = data;
504 	struct zfcp_port *port = fc_req->ct_els.port;
505 	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;
506 
507 	if (fc_req->ct_els.status) {
508 		/* request rejected or timed out */
509 		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
510 					    "fcadh_1");
511 		goto out;
512 	}
513 
514 	if (!port->wwnn)
515 		port->wwnn = be64_to_cpu(adisc_resp->adisc_wwnn);
516 
517 	if ((port->wwpn != be64_to_cpu(adisc_resp->adisc_wwpn)) ||
518 	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
519 		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
520 				     "fcadh_2");
521 		goto out;
522 	}
523 
524 	/* re-init to undo drop from zfcp_fc_adisc() */
525 	port->d_id = ntoh24(adisc_resp->adisc_port_id);
526 	/* port is good, unblock rport without going through erp */
527 	zfcp_scsi_schedule_rport_register(port);
528  out:
529 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
530 	put_device(&port->dev);
531 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
532 }
533 
534 static int zfcp_fc_adisc(struct zfcp_port *port)
535 {
536 	struct zfcp_fc_req *fc_req;
537 	struct zfcp_adapter *adapter = port->adapter;
538 	struct Scsi_Host *shost = adapter->scsi_host;
539 	u32 d_id;
540 	int ret;
541 
542 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
543 	if (!fc_req)
544 		return -ENOMEM;
545 
546 	fc_req->ct_els.port = port;
547 	fc_req->ct_els.req = &fc_req->sg_req;
548 	fc_req->ct_els.resp = &fc_req->sg_rsp;
549 	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
550 		    sizeof(struct fc_els_adisc));
551 	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
552 		    sizeof(struct fc_els_adisc));
553 
554 	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
555 	fc_req->ct_els.handler_data = fc_req;
556 
557 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
558 	   without FC-AL-2 capability, so we don't set it */
559 	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
560 	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
561 	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
562 	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
563 
564 	d_id = port->d_id; /* remember as destination for send els below */
565 	/*
566 	 * Force fresh GID_PN lookup on next port recovery.
567 	 * Must happen after request setup and before sending request,
568 	 * to prevent race with port->d_id re-init in zfcp_fc_adisc_handler().
569 	 */
570 	port->d_id = 0;
571 
572 	ret = zfcp_fsf_send_els(adapter, d_id, &fc_req->ct_els,
573 				ZFCP_FC_CTELS_TMO);
574 	if (ret)
575 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
576 
577 	return ret;
578 }
579 
580 void zfcp_fc_link_test_work(struct work_struct *work)
581 {
582 	struct zfcp_port *port =
583 		container_of(work, struct zfcp_port, test_link_work);
584 	int retval;
585 
586 	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
587 	get_device(&port->dev);
588 	port->rport_task = RPORT_DEL;
589 	zfcp_scsi_rport_work(&port->rport_work);
590 
591 	/* only issue one test command at one time per port */
592 	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
593 		goto out;
594 
595 	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
596 
597 	retval = zfcp_fc_adisc(port);
598 	if (retval == 0)
599 		return;
600 
601 	/* send of ADISC was not possible */
602 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
603 	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
604 
605 out:
606 	put_device(&port->dev);
607 }
608 
609 /**
610  * zfcp_fc_test_link - lightweight link test procedure
611  * @port: port to be tested
612  *
613  * Test status of a link to a remote port using the ELS command ADISC.
614  * If there is a problem with the remote port, error recovery steps
615  * will be triggered.
616  */
617 void zfcp_fc_test_link(struct zfcp_port *port)
618 {
619 	get_device(&port->dev);
620 	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
621 		put_device(&port->dev);
622 }
623 
624 /**
625  * zfcp_fc_sg_free_table - free memory used by scatterlists
626  * @sg: pointer to scatterlist
627  * @count: number of scatterlist which are to be free'ed
628  * the scatterlist are expected to reference pages always
629  */
630 static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
631 {
632 	int i;
633 
634 	for (i = 0; i < count; i++, sg = sg_next(sg))
635 		if (sg)
636 			free_page((unsigned long) sg_virt(sg));
637 		else
638 			break;
639 }
640 
641 /**
642  * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
643  * @sg: pointer to struct scatterlist
644  * @count: number of scatterlists which should be assigned with buffers
645  * of size page
646  *
647  * Returns: 0 on success, -ENOMEM otherwise
648  */
649 static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
650 {
651 	void *addr;
652 	int i;
653 
654 	sg_init_table(sg, count);
655 	for (i = 0; i < count; i++, sg = sg_next(sg)) {
656 		addr = (void *) get_zeroed_page(GFP_KERNEL);
657 		if (!addr) {
658 			zfcp_fc_sg_free_table(sg, i);
659 			return -ENOMEM;
660 		}
661 		sg_set_buf(sg, addr, PAGE_SIZE);
662 	}
663 	return 0;
664 }
665 
666 static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
667 {
668 	struct zfcp_fc_req *fc_req;
669 
670 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
671 	if (!fc_req)
672 		return NULL;
673 
674 	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
675 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
676 		return NULL;
677 	}
678 
679 	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
680 		    sizeof(struct zfcp_fc_gpn_ft_req));
681 
682 	return fc_req;
683 }
684 
685 static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
686 			       struct zfcp_adapter *adapter, int max_bytes)
687 {
688 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
689 	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
690 	DECLARE_COMPLETION_ONSTACK(completion);
691 	int ret;
692 
693 	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
694 	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
695 
696 	ct_els->handler = zfcp_fc_complete;
697 	ct_els->handler_data = &completion;
698 	ct_els->req = &fc_req->sg_req;
699 	ct_els->resp = &fc_req->sg_rsp;
700 
701 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
702 			       ZFCP_FC_CTELS_TMO);
703 	if (!ret)
704 		wait_for_completion(&completion);
705 	return ret;
706 }
707 
708 static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
709 {
710 	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
711 		return;
712 
713 	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
714 
715 	if ((port->supported_classes != 0) ||
716 	    !list_empty(&port->unit_list))
717 		return;
718 
719 	list_move_tail(&port->list, lh);
720 }
721 
722 static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
723 			       struct zfcp_adapter *adapter, int max_entries)
724 {
725 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
726 	struct scatterlist *sg = &fc_req->sg_rsp;
727 	struct fc_ct_hdr *hdr = sg_virt(sg);
728 	struct fc_gpn_ft_resp *acc = sg_virt(sg);
729 	struct zfcp_port *port, *tmp;
730 	unsigned long flags;
731 	LIST_HEAD(remove_lh);
732 	u32 d_id;
733 	int ret = 0, x, last = 0;
734 
735 	if (ct_els->status)
736 		return -EIO;
737 
738 	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
739 		if (hdr->ct_reason == FC_FS_RJT_UNABL)
740 			return -EAGAIN; /* might be a temporary condition */
741 		return -EIO;
742 	}
743 
744 	if (hdr->ct_mr_size) {
745 		dev_warn(&adapter->ccw_device->dev,
746 			 "The name server reported %d words residual data\n",
747 			 hdr->ct_mr_size);
748 		return -E2BIG;
749 	}
750 
751 	/* first entry is the header */
752 	for (x = 1; x < max_entries && !last; x++) {
753 		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
754 			acc++;
755 		else
756 			acc = sg_virt(++sg);
757 
758 		last = acc->fp_flags & FC_NS_FID_LAST;
759 		d_id = ntoh24(acc->fp_fid);
760 
761 		/* don't attach ports with a well known address */
762 		if (d_id >= FC_FID_WELL_KNOWN_BASE)
763 			continue;
764 		/* skip the adapter's port and known remote ports */
765 		if (be64_to_cpu(acc->fp_wwpn) ==
766 		    fc_host_port_name(adapter->scsi_host))
767 			continue;
768 
769 		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
770 					 ZFCP_STATUS_COMMON_NOESC, d_id);
771 		if (!IS_ERR(port))
772 			zfcp_erp_port_reopen(port, 0, "fcegpf1");
773 		else if (PTR_ERR(port) != -EEXIST)
774 			ret = PTR_ERR(port);
775 	}
776 
777 	zfcp_erp_wait(adapter);
778 	write_lock_irqsave(&adapter->port_list_lock, flags);
779 	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
780 		zfcp_fc_validate_port(port, &remove_lh);
781 	write_unlock_irqrestore(&adapter->port_list_lock, flags);
782 
783 	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
784 		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
785 		device_unregister(&port->dev);
786 	}
787 
788 	return ret;
789 }
790 
791 /**
792  * zfcp_fc_scan_ports - scan remote ports and attach new ports
793  * @work: reference to scheduled work
794  */
795 void zfcp_fc_scan_ports(struct work_struct *work)
796 {
797 	struct delayed_work *dw = to_delayed_work(work);
798 	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
799 						    scan_work);
800 	int ret, i;
801 	struct zfcp_fc_req *fc_req;
802 	int chain, max_entries, buf_num, max_bytes;
803 
804 	zfcp_fc_port_scan_time(adapter);
805 
806 	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
807 	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
808 	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
809 	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
810 
811 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
812 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
813 		return;
814 
815 	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
816 		return;
817 
818 	fc_req = zfcp_fc_alloc_sg_env(buf_num);
819 	if (!fc_req)
820 		goto out;
821 
822 	for (i = 0; i < 3; i++) {
823 		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
824 		if (!ret) {
825 			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
826 			if (ret == -EAGAIN)
827 				ssleep(1);
828 			else
829 				break;
830 		}
831 	}
832 	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
833 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
834 out:
835 	zfcp_fc_wka_port_put(&adapter->gs->ds);
836 }
837 
838 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
839 			struct zfcp_fc_req *fc_req)
840 {
841 	DECLARE_COMPLETION_ONSTACK(completion);
842 	char devno[] = "DEVNO:";
843 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
844 	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
845 	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
846 	int ret;
847 
848 	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
849 			   FC_SYMBOLIC_NAME_SIZE);
850 	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
851 
852 	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
853 	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
854 
855 	ct_els->handler = zfcp_fc_complete;
856 	ct_els->handler_data = &completion;
857 	ct_els->req = &fc_req->sg_req;
858 	ct_els->resp = &fc_req->sg_rsp;
859 
860 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
861 			       ZFCP_FC_CTELS_TMO);
862 	if (ret)
863 		return ret;
864 
865 	wait_for_completion(&completion);
866 	if (ct_els->status)
867 		return ct_els->status;
868 
869 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
870 	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
871 		snprintf(fc_host_symbolic_name(adapter->scsi_host),
872 			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
873 			 gspn_rsp->gspn.fp_name, devno,
874 			 dev_name(&adapter->ccw_device->dev),
875 			 init_utsname()->nodename);
876 	else
877 		strlcpy(fc_host_symbolic_name(adapter->scsi_host),
878 			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
879 
880 	return 0;
881 }
882 
883 static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
884 			 struct zfcp_fc_req *fc_req)
885 {
886 	DECLARE_COMPLETION_ONSTACK(completion);
887 	struct Scsi_Host *shost = adapter->scsi_host;
888 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
889 	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
890 	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
891 	int ret, len;
892 
893 	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
894 			   FC_SYMBOLIC_NAME_SIZE);
895 	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
896 	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
897 		      FC_SYMBOLIC_NAME_SIZE);
898 	rspn_req->rspn.fr_name_len = len;
899 
900 	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
901 	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
902 
903 	ct_els->handler = zfcp_fc_complete;
904 	ct_els->handler_data = &completion;
905 	ct_els->req = &fc_req->sg_req;
906 	ct_els->resp = &fc_req->sg_rsp;
907 
908 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
909 			       ZFCP_FC_CTELS_TMO);
910 	if (!ret)
911 		wait_for_completion(&completion);
912 }
913 
914 /**
915  * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
916  * @work: ns_up_work of the adapter where to update the symbolic port name
917  *
918  * Retrieve the current symbolic port name that may have been set by
919  * the hardware using the GSPN request and update the fc_host
920  * symbolic_name sysfs attribute. When running in NPIV mode (and hence
921  * the port name is unique for this system), update the symbolic port
922  * name to add Linux specific information and update the FC nameserver
923  * using the RSPN request.
924  */
925 void zfcp_fc_sym_name_update(struct work_struct *work)
926 {
927 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
928 						    ns_up_work);
929 	int ret;
930 	struct zfcp_fc_req *fc_req;
931 
932 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
933 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
934 		return;
935 
936 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
937 	if (!fc_req)
938 		return;
939 
940 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
941 	if (ret)
942 		goto out_free;
943 
944 	ret = zfcp_fc_gspn(adapter, fc_req);
945 	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
946 		goto out_ds_put;
947 
948 	memset(fc_req, 0, sizeof(*fc_req));
949 	zfcp_fc_rspn(adapter, fc_req);
950 
951 out_ds_put:
952 	zfcp_fc_wka_port_put(&adapter->gs->ds);
953 out_free:
954 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
955 }
956 
957 static void zfcp_fc_ct_els_job_handler(void *data)
958 {
959 	struct bsg_job *job = data;
960 	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
961 	struct fc_bsg_reply *jr = job->reply;
962 
963 	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
964 	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
965 	jr->result = zfcp_ct_els->status ? -EIO : 0;
966 	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
967 }
968 
969 static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
970 {
971 	u32 preamble_word1;
972 	u8 gs_type;
973 	struct zfcp_adapter *adapter;
974 	struct fc_bsg_request *bsg_request = job->request;
975 	struct fc_rport *rport = fc_bsg_to_rport(job);
976 	struct Scsi_Host *shost;
977 
978 	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
979 	gs_type = (preamble_word1 & 0xff000000) >> 24;
980 
981 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
982 	adapter = (struct zfcp_adapter *) shost->hostdata[0];
983 
984 	switch (gs_type) {
985 	case FC_FST_ALIAS:
986 		return &adapter->gs->as;
987 	case FC_FST_MGMT:
988 		return &adapter->gs->ms;
989 	case FC_FST_TIME:
990 		return &adapter->gs->ts;
991 		break;
992 	case FC_FST_DIR:
993 		return &adapter->gs->ds;
994 		break;
995 	default:
996 		return NULL;
997 	}
998 }
999 
1000 static void zfcp_fc_ct_job_handler(void *data)
1001 {
1002 	struct bsg_job *job = data;
1003 	struct zfcp_fc_wka_port *wka_port;
1004 
1005 	wka_port = zfcp_fc_job_wka_port(job);
1006 	zfcp_fc_wka_port_put(wka_port);
1007 
1008 	zfcp_fc_ct_els_job_handler(data);
1009 }
1010 
1011 static int zfcp_fc_exec_els_job(struct bsg_job *job,
1012 				struct zfcp_adapter *adapter)
1013 {
1014 	struct zfcp_fsf_ct_els *els = job->dd_data;
1015 	struct fc_rport *rport = fc_bsg_to_rport(job);
1016 	struct fc_bsg_request *bsg_request = job->request;
1017 	struct zfcp_port *port;
1018 	u32 d_id;
1019 
1020 	if (rport) {
1021 		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
1022 		if (!port)
1023 			return -EINVAL;
1024 
1025 		d_id = port->d_id;
1026 		put_device(&port->dev);
1027 	} else
1028 		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);
1029 
1030 	els->handler = zfcp_fc_ct_els_job_handler;
1031 	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
1032 }
1033 
1034 static int zfcp_fc_exec_ct_job(struct bsg_job *job,
1035 			       struct zfcp_adapter *adapter)
1036 {
1037 	int ret;
1038 	struct zfcp_fsf_ct_els *ct = job->dd_data;
1039 	struct zfcp_fc_wka_port *wka_port;
1040 
1041 	wka_port = zfcp_fc_job_wka_port(job);
1042 	if (!wka_port)
1043 		return -EINVAL;
1044 
1045 	ret = zfcp_fc_wka_port_get(wka_port);
1046 	if (ret)
1047 		return ret;
1048 
1049 	ct->handler = zfcp_fc_ct_job_handler;
1050 	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
1051 	if (ret)
1052 		zfcp_fc_wka_port_put(wka_port);
1053 
1054 	return ret;
1055 }
1056 
1057 int zfcp_fc_exec_bsg_job(struct bsg_job *job)
1058 {
1059 	struct Scsi_Host *shost;
1060 	struct zfcp_adapter *adapter;
1061 	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
1062 	struct fc_bsg_request *bsg_request = job->request;
1063 	struct fc_rport *rport = fc_bsg_to_rport(job);
1064 
1065 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1066 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
1067 
1068 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
1069 		return -EINVAL;
1070 
1071 	ct_els->req = job->request_payload.sg_list;
1072 	ct_els->resp = job->reply_payload.sg_list;
1073 	ct_els->handler_data = job;
1074 
1075 	switch (bsg_request->msgcode) {
1076 	case FC_BSG_RPT_ELS:
1077 	case FC_BSG_HST_ELS_NOLOGIN:
1078 		return zfcp_fc_exec_els_job(job, adapter);
1079 	case FC_BSG_RPT_CT:
1080 	case FC_BSG_HST_CT:
1081 		return zfcp_fc_exec_ct_job(job, adapter);
1082 	default:
1083 		return -EINVAL;
1084 	}
1085 }
1086 
1087 int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
1088 {
1089 	/* hardware tracks timeout, reset bsg timeout to not interfere */
1090 	return -EAGAIN;
1091 }
1092 
1093 int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1094 {
1095 	struct zfcp_fc_wka_ports *wka_ports;
1096 
1097 	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1098 	if (!wka_ports)
1099 		return -ENOMEM;
1100 
1101 	adapter->gs = wka_ports;
1102 	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1103 	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1104 	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1105 	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1106 
1107 	return 0;
1108 }
1109 
1110 void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1111 {
1112 	kfree(adapter->gs);
1113 	adapter->gs = NULL;
1114 }
1115 
1116