xref: /openbmc/linux/drivers/s390/scsi/zfcp_fc.c (revision d0e22329)
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 get_random_int() % 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 		if (!port->d_id)
243 			zfcp_erp_port_reopen(port,
244 					     ZFCP_STATUS_COMMON_ERP_FAILED,
245 					     "fcrscn1");
246 	}
247 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
248 }
249 
250 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
251 {
252 	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
253 	struct fc_els_rscn *head;
254 	struct fc_els_rscn_page *page;
255 	u16 i;
256 	u16 no_entries;
257 	unsigned int afmt;
258 
259 	head = (struct fc_els_rscn *) status_buffer->payload.data;
260 	page = (struct fc_els_rscn_page *) head;
261 
262 	/* see FC-FS */
263 	no_entries = be16_to_cpu(head->rscn_plen) /
264 		sizeof(struct fc_els_rscn_page);
265 
266 	for (i = 1; i < no_entries; i++) {
267 		/* skip head and start with 1st element */
268 		page++;
269 		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
270 		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
271 				       page);
272 		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
273 				      *(u32 *)page);
274 	}
275 	zfcp_fc_conditional_port_scan(fsf_req->adapter);
276 }
277 
278 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
279 {
280 	unsigned long flags;
281 	struct zfcp_adapter *adapter = req->adapter;
282 	struct zfcp_port *port;
283 
284 	read_lock_irqsave(&adapter->port_list_lock, flags);
285 	list_for_each_entry(port, &adapter->port_list, list)
286 		if (port->wwpn == wwpn) {
287 			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
288 			break;
289 		}
290 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
291 }
292 
293 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
294 {
295 	struct fsf_status_read_buffer *status_buffer;
296 	struct fc_els_flogi *plogi;
297 
298 	status_buffer = (struct fsf_status_read_buffer *) req->data;
299 	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
300 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(plogi->fl_wwpn));
301 }
302 
303 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
304 {
305 	struct fsf_status_read_buffer *status_buffer =
306 		(struct fsf_status_read_buffer *)req->data;
307 	struct fc_els_logo *logo =
308 		(struct fc_els_logo *) status_buffer->payload.data;
309 
310 	zfcp_fc_incoming_wwpn(req, be64_to_cpu(logo->fl_n_port_wwn));
311 }
312 
313 /**
314  * zfcp_fc_incoming_els - handle incoming ELS
315  * @fsf_req: request which contains incoming ELS
316  */
317 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
318 {
319 	struct fsf_status_read_buffer *status_buffer =
320 		(struct fsf_status_read_buffer *) fsf_req->data;
321 	unsigned int els_type = status_buffer->payload.data[0];
322 
323 	zfcp_dbf_san_in_els("fciels1", fsf_req);
324 	if (els_type == ELS_PLOGI)
325 		zfcp_fc_incoming_plogi(fsf_req);
326 	else if (els_type == ELS_LOGO)
327 		zfcp_fc_incoming_logo(fsf_req);
328 	else if (els_type == ELS_RSCN)
329 		zfcp_fc_incoming_rscn(fsf_req);
330 }
331 
332 static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
333 {
334 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
335 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
336 
337 	if (ct_els->status)
338 		return;
339 	if (gid_pn_rsp->ct_hdr.ct_cmd != cpu_to_be16(FC_FS_ACC))
340 		return;
341 
342 	/* looks like a valid d_id */
343 	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
344 }
345 
346 static void zfcp_fc_complete(void *data)
347 {
348 	complete(data);
349 }
350 
351 static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
352 {
353 	ct_hdr->ct_rev = FC_CT_REV;
354 	ct_hdr->ct_fs_type = FC_FST_DIR;
355 	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
356 	ct_hdr->ct_cmd = cpu_to_be16(cmd);
357 	ct_hdr->ct_mr_size = cpu_to_be16(mr_size / 4);
358 }
359 
360 static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
361 				     struct zfcp_fc_req *fc_req)
362 {
363 	struct zfcp_adapter *adapter = port->adapter;
364 	DECLARE_COMPLETION_ONSTACK(completion);
365 	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
366 	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
367 	int ret;
368 
369 	/* setup parameters for send generic command */
370 	fc_req->ct_els.port = port;
371 	fc_req->ct_els.handler = zfcp_fc_complete;
372 	fc_req->ct_els.handler_data = &completion;
373 	fc_req->ct_els.req = &fc_req->sg_req;
374 	fc_req->ct_els.resp = &fc_req->sg_rsp;
375 	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
376 	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));
377 
378 	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
379 			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
380 	gid_pn_req->gid_pn.fn_wwpn = cpu_to_be64(port->wwpn);
381 
382 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
383 			       adapter->pool.gid_pn_req,
384 			       ZFCP_FC_CTELS_TMO);
385 	if (!ret) {
386 		wait_for_completion(&completion);
387 		zfcp_fc_ns_gid_pn_eval(fc_req);
388 	}
389 	return ret;
390 }
391 
392 /**
393  * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
394  * @port: port where GID_PN request is needed
395  * return: -ENOMEM on error, 0 otherwise
396  */
397 static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
398 {
399 	int ret;
400 	struct zfcp_fc_req *fc_req;
401 	struct zfcp_adapter *adapter = port->adapter;
402 
403 	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
404 	if (!fc_req)
405 		return -ENOMEM;
406 
407 	memset(fc_req, 0, sizeof(*fc_req));
408 
409 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
410 	if (ret)
411 		goto out;
412 
413 	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);
414 
415 	zfcp_fc_wka_port_put(&adapter->gs->ds);
416 out:
417 	mempool_free(fc_req, adapter->pool.gid_pn);
418 	return ret;
419 }
420 
421 void zfcp_fc_port_did_lookup(struct work_struct *work)
422 {
423 	int ret;
424 	struct zfcp_port *port = container_of(work, struct zfcp_port,
425 					      gid_pn_work);
426 
427 	set_worker_desc("zgidpn%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
428 	ret = zfcp_fc_ns_gid_pn(port);
429 	if (ret) {
430 		/* could not issue gid_pn for some reason */
431 		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
432 		goto out;
433 	}
434 
435 	if (!port->d_id) {
436 		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
437 		goto out;
438 	}
439 
440 	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
441 out:
442 	put_device(&port->dev);
443 }
444 
445 /**
446  * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
447  * @port: The zfcp_port to lookup the d_id for.
448  */
449 void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
450 {
451 	get_device(&port->dev);
452 	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
453 		put_device(&port->dev);
454 }
455 
456 /**
457  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
458  * @port: zfcp_port structure
459  * @plogi: plogi payload
460  *
461  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
462  */
463 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
464 {
465 	if (be64_to_cpu(plogi->fl_wwpn) != port->wwpn) {
466 		port->d_id = 0;
467 		dev_warn(&port->adapter->ccw_device->dev,
468 			 "A port opened with WWPN 0x%016Lx returned data that "
469 			 "identifies it as WWPN 0x%016Lx\n",
470 			 (unsigned long long) port->wwpn,
471 			 (unsigned long long) be64_to_cpu(plogi->fl_wwpn));
472 		return;
473 	}
474 
475 	port->wwnn = be64_to_cpu(plogi->fl_wwnn);
476 	port->maxframe_size = be16_to_cpu(plogi->fl_csp.sp_bb_data);
477 
478 	if (plogi->fl_cssp[0].cp_class & cpu_to_be16(FC_CPC_VALID))
479 		port->supported_classes |= FC_COS_CLASS1;
480 	if (plogi->fl_cssp[1].cp_class & cpu_to_be16(FC_CPC_VALID))
481 		port->supported_classes |= FC_COS_CLASS2;
482 	if (plogi->fl_cssp[2].cp_class & cpu_to_be16(FC_CPC_VALID))
483 		port->supported_classes |= FC_COS_CLASS3;
484 	if (plogi->fl_cssp[3].cp_class & cpu_to_be16(FC_CPC_VALID))
485 		port->supported_classes |= FC_COS_CLASS4;
486 }
487 
488 static void zfcp_fc_adisc_handler(void *data)
489 {
490 	struct zfcp_fc_req *fc_req = data;
491 	struct zfcp_port *port = fc_req->ct_els.port;
492 	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;
493 
494 	if (fc_req->ct_els.status) {
495 		/* request rejected or timed out */
496 		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
497 					    "fcadh_1");
498 		goto out;
499 	}
500 
501 	if (!port->wwnn)
502 		port->wwnn = be64_to_cpu(adisc_resp->adisc_wwnn);
503 
504 	if ((port->wwpn != be64_to_cpu(adisc_resp->adisc_wwpn)) ||
505 	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
506 		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
507 				     "fcadh_2");
508 		goto out;
509 	}
510 
511 	/* port is good, unblock rport without going through erp */
512 	zfcp_scsi_schedule_rport_register(port);
513  out:
514 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
515 	put_device(&port->dev);
516 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
517 }
518 
519 static int zfcp_fc_adisc(struct zfcp_port *port)
520 {
521 	struct zfcp_fc_req *fc_req;
522 	struct zfcp_adapter *adapter = port->adapter;
523 	struct Scsi_Host *shost = adapter->scsi_host;
524 	int ret;
525 
526 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
527 	if (!fc_req)
528 		return -ENOMEM;
529 
530 	fc_req->ct_els.port = port;
531 	fc_req->ct_els.req = &fc_req->sg_req;
532 	fc_req->ct_els.resp = &fc_req->sg_rsp;
533 	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
534 		    sizeof(struct fc_els_adisc));
535 	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
536 		    sizeof(struct fc_els_adisc));
537 
538 	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
539 	fc_req->ct_els.handler_data = fc_req;
540 
541 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
542 	   without FC-AL-2 capability, so we don't set it */
543 	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
544 	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
545 	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
546 	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
547 
548 	ret = zfcp_fsf_send_els(adapter, port->d_id, &fc_req->ct_els,
549 				ZFCP_FC_CTELS_TMO);
550 	if (ret)
551 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
552 
553 	return ret;
554 }
555 
556 void zfcp_fc_link_test_work(struct work_struct *work)
557 {
558 	struct zfcp_port *port =
559 		container_of(work, struct zfcp_port, test_link_work);
560 	int retval;
561 
562 	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
563 	get_device(&port->dev);
564 	port->rport_task = RPORT_DEL;
565 	zfcp_scsi_rport_work(&port->rport_work);
566 
567 	/* only issue one test command at one time per port */
568 	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
569 		goto out;
570 
571 	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
572 
573 	retval = zfcp_fc_adisc(port);
574 	if (retval == 0)
575 		return;
576 
577 	/* send of ADISC was not possible */
578 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
579 	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
580 
581 out:
582 	put_device(&port->dev);
583 }
584 
585 /**
586  * zfcp_fc_test_link - lightweight link test procedure
587  * @port: port to be tested
588  *
589  * Test status of a link to a remote port using the ELS command ADISC.
590  * If there is a problem with the remote port, error recovery steps
591  * will be triggered.
592  */
593 void zfcp_fc_test_link(struct zfcp_port *port)
594 {
595 	get_device(&port->dev);
596 	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
597 		put_device(&port->dev);
598 }
599 
600 /**
601  * zfcp_fc_sg_free_table - free memory used by scatterlists
602  * @sg: pointer to scatterlist
603  * @count: number of scatterlist which are to be free'ed
604  * the scatterlist are expected to reference pages always
605  */
606 static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
607 {
608 	int i;
609 
610 	for (i = 0; i < count; i++, sg++)
611 		if (sg)
612 			free_page((unsigned long) sg_virt(sg));
613 		else
614 			break;
615 }
616 
617 /**
618  * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
619  * @sg: pointer to struct scatterlist
620  * @count: number of scatterlists which should be assigned with buffers
621  * of size page
622  *
623  * Returns: 0 on success, -ENOMEM otherwise
624  */
625 static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
626 {
627 	void *addr;
628 	int i;
629 
630 	sg_init_table(sg, count);
631 	for (i = 0; i < count; i++, sg++) {
632 		addr = (void *) get_zeroed_page(GFP_KERNEL);
633 		if (!addr) {
634 			zfcp_fc_sg_free_table(sg, i);
635 			return -ENOMEM;
636 		}
637 		sg_set_buf(sg, addr, PAGE_SIZE);
638 	}
639 	return 0;
640 }
641 
642 static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
643 {
644 	struct zfcp_fc_req *fc_req;
645 
646 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
647 	if (!fc_req)
648 		return NULL;
649 
650 	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
651 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
652 		return NULL;
653 	}
654 
655 	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
656 		    sizeof(struct zfcp_fc_gpn_ft_req));
657 
658 	return fc_req;
659 }
660 
661 static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
662 			       struct zfcp_adapter *adapter, int max_bytes)
663 {
664 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
665 	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
666 	DECLARE_COMPLETION_ONSTACK(completion);
667 	int ret;
668 
669 	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
670 	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
671 
672 	ct_els->handler = zfcp_fc_complete;
673 	ct_els->handler_data = &completion;
674 	ct_els->req = &fc_req->sg_req;
675 	ct_els->resp = &fc_req->sg_rsp;
676 
677 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
678 			       ZFCP_FC_CTELS_TMO);
679 	if (!ret)
680 		wait_for_completion(&completion);
681 	return ret;
682 }
683 
684 static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
685 {
686 	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
687 		return;
688 
689 	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
690 
691 	if ((port->supported_classes != 0) ||
692 	    !list_empty(&port->unit_list))
693 		return;
694 
695 	list_move_tail(&port->list, lh);
696 }
697 
698 static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
699 			       struct zfcp_adapter *adapter, int max_entries)
700 {
701 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
702 	struct scatterlist *sg = &fc_req->sg_rsp;
703 	struct fc_ct_hdr *hdr = sg_virt(sg);
704 	struct fc_gpn_ft_resp *acc = sg_virt(sg);
705 	struct zfcp_port *port, *tmp;
706 	unsigned long flags;
707 	LIST_HEAD(remove_lh);
708 	u32 d_id;
709 	int ret = 0, x, last = 0;
710 
711 	if (ct_els->status)
712 		return -EIO;
713 
714 	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
715 		if (hdr->ct_reason == FC_FS_RJT_UNABL)
716 			return -EAGAIN; /* might be a temporary condition */
717 		return -EIO;
718 	}
719 
720 	if (hdr->ct_mr_size) {
721 		dev_warn(&adapter->ccw_device->dev,
722 			 "The name server reported %d words residual data\n",
723 			 hdr->ct_mr_size);
724 		return -E2BIG;
725 	}
726 
727 	/* first entry is the header */
728 	for (x = 1; x < max_entries && !last; x++) {
729 		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
730 			acc++;
731 		else
732 			acc = sg_virt(++sg);
733 
734 		last = acc->fp_flags & FC_NS_FID_LAST;
735 		d_id = ntoh24(acc->fp_fid);
736 
737 		/* don't attach ports with a well known address */
738 		if (d_id >= FC_FID_WELL_KNOWN_BASE)
739 			continue;
740 		/* skip the adapter's port and known remote ports */
741 		if (be64_to_cpu(acc->fp_wwpn) ==
742 		    fc_host_port_name(adapter->scsi_host))
743 			continue;
744 
745 		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
746 					 ZFCP_STATUS_COMMON_NOESC, d_id);
747 		if (!IS_ERR(port))
748 			zfcp_erp_port_reopen(port, 0, "fcegpf1");
749 		else if (PTR_ERR(port) != -EEXIST)
750 			ret = PTR_ERR(port);
751 	}
752 
753 	zfcp_erp_wait(adapter);
754 	write_lock_irqsave(&adapter->port_list_lock, flags);
755 	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
756 		zfcp_fc_validate_port(port, &remove_lh);
757 	write_unlock_irqrestore(&adapter->port_list_lock, flags);
758 
759 	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
760 		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
761 		device_unregister(&port->dev);
762 	}
763 
764 	return ret;
765 }
766 
767 /**
768  * zfcp_fc_scan_ports - scan remote ports and attach new ports
769  * @work: reference to scheduled work
770  */
771 void zfcp_fc_scan_ports(struct work_struct *work)
772 {
773 	struct delayed_work *dw = to_delayed_work(work);
774 	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
775 						    scan_work);
776 	int ret, i;
777 	struct zfcp_fc_req *fc_req;
778 	int chain, max_entries, buf_num, max_bytes;
779 
780 	zfcp_fc_port_scan_time(adapter);
781 
782 	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
783 	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
784 	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
785 	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
786 
787 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
788 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
789 		return;
790 
791 	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
792 		return;
793 
794 	fc_req = zfcp_fc_alloc_sg_env(buf_num);
795 	if (!fc_req)
796 		goto out;
797 
798 	for (i = 0; i < 3; i++) {
799 		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
800 		if (!ret) {
801 			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
802 			if (ret == -EAGAIN)
803 				ssleep(1);
804 			else
805 				break;
806 		}
807 	}
808 	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
809 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
810 out:
811 	zfcp_fc_wka_port_put(&adapter->gs->ds);
812 }
813 
814 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
815 			struct zfcp_fc_req *fc_req)
816 {
817 	DECLARE_COMPLETION_ONSTACK(completion);
818 	char devno[] = "DEVNO:";
819 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
820 	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
821 	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
822 	int ret;
823 
824 	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
825 			   FC_SYMBOLIC_NAME_SIZE);
826 	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
827 
828 	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
829 	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
830 
831 	ct_els->handler = zfcp_fc_complete;
832 	ct_els->handler_data = &completion;
833 	ct_els->req = &fc_req->sg_req;
834 	ct_els->resp = &fc_req->sg_rsp;
835 
836 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
837 			       ZFCP_FC_CTELS_TMO);
838 	if (ret)
839 		return ret;
840 
841 	wait_for_completion(&completion);
842 	if (ct_els->status)
843 		return ct_els->status;
844 
845 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
846 	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
847 		snprintf(fc_host_symbolic_name(adapter->scsi_host),
848 			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
849 			 gspn_rsp->gspn.fp_name, devno,
850 			 dev_name(&adapter->ccw_device->dev),
851 			 init_utsname()->nodename);
852 	else
853 		strlcpy(fc_host_symbolic_name(adapter->scsi_host),
854 			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
855 
856 	return 0;
857 }
858 
859 static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
860 			 struct zfcp_fc_req *fc_req)
861 {
862 	DECLARE_COMPLETION_ONSTACK(completion);
863 	struct Scsi_Host *shost = adapter->scsi_host;
864 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
865 	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
866 	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
867 	int ret, len;
868 
869 	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
870 			   FC_SYMBOLIC_NAME_SIZE);
871 	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
872 	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
873 		      FC_SYMBOLIC_NAME_SIZE);
874 	rspn_req->rspn.fr_name_len = len;
875 
876 	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
877 	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
878 
879 	ct_els->handler = zfcp_fc_complete;
880 	ct_els->handler_data = &completion;
881 	ct_els->req = &fc_req->sg_req;
882 	ct_els->resp = &fc_req->sg_rsp;
883 
884 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
885 			       ZFCP_FC_CTELS_TMO);
886 	if (!ret)
887 		wait_for_completion(&completion);
888 }
889 
890 /**
891  * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
892  * @work: ns_up_work of the adapter where to update the symbolic port name
893  *
894  * Retrieve the current symbolic port name that may have been set by
895  * the hardware using the GSPN request and update the fc_host
896  * symbolic_name sysfs attribute. When running in NPIV mode (and hence
897  * the port name is unique for this system), update the symbolic port
898  * name to add Linux specific information and update the FC nameserver
899  * using the RSPN request.
900  */
901 void zfcp_fc_sym_name_update(struct work_struct *work)
902 {
903 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
904 						    ns_up_work);
905 	int ret;
906 	struct zfcp_fc_req *fc_req;
907 
908 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
909 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
910 		return;
911 
912 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
913 	if (!fc_req)
914 		return;
915 
916 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
917 	if (ret)
918 		goto out_free;
919 
920 	ret = zfcp_fc_gspn(adapter, fc_req);
921 	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
922 		goto out_ds_put;
923 
924 	memset(fc_req, 0, sizeof(*fc_req));
925 	zfcp_fc_rspn(adapter, fc_req);
926 
927 out_ds_put:
928 	zfcp_fc_wka_port_put(&adapter->gs->ds);
929 out_free:
930 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
931 }
932 
933 static void zfcp_fc_ct_els_job_handler(void *data)
934 {
935 	struct bsg_job *job = data;
936 	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
937 	struct fc_bsg_reply *jr = job->reply;
938 
939 	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
940 	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
941 	jr->result = zfcp_ct_els->status ? -EIO : 0;
942 	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
943 }
944 
945 static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
946 {
947 	u32 preamble_word1;
948 	u8 gs_type;
949 	struct zfcp_adapter *adapter;
950 	struct fc_bsg_request *bsg_request = job->request;
951 	struct fc_rport *rport = fc_bsg_to_rport(job);
952 	struct Scsi_Host *shost;
953 
954 	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
955 	gs_type = (preamble_word1 & 0xff000000) >> 24;
956 
957 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
958 	adapter = (struct zfcp_adapter *) shost->hostdata[0];
959 
960 	switch (gs_type) {
961 	case FC_FST_ALIAS:
962 		return &adapter->gs->as;
963 	case FC_FST_MGMT:
964 		return &adapter->gs->ms;
965 	case FC_FST_TIME:
966 		return &adapter->gs->ts;
967 		break;
968 	case FC_FST_DIR:
969 		return &adapter->gs->ds;
970 		break;
971 	default:
972 		return NULL;
973 	}
974 }
975 
976 static void zfcp_fc_ct_job_handler(void *data)
977 {
978 	struct bsg_job *job = data;
979 	struct zfcp_fc_wka_port *wka_port;
980 
981 	wka_port = zfcp_fc_job_wka_port(job);
982 	zfcp_fc_wka_port_put(wka_port);
983 
984 	zfcp_fc_ct_els_job_handler(data);
985 }
986 
987 static int zfcp_fc_exec_els_job(struct bsg_job *job,
988 				struct zfcp_adapter *adapter)
989 {
990 	struct zfcp_fsf_ct_els *els = job->dd_data;
991 	struct fc_rport *rport = fc_bsg_to_rport(job);
992 	struct fc_bsg_request *bsg_request = job->request;
993 	struct zfcp_port *port;
994 	u32 d_id;
995 
996 	if (rport) {
997 		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
998 		if (!port)
999 			return -EINVAL;
1000 
1001 		d_id = port->d_id;
1002 		put_device(&port->dev);
1003 	} else
1004 		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);
1005 
1006 	els->handler = zfcp_fc_ct_els_job_handler;
1007 	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
1008 }
1009 
1010 static int zfcp_fc_exec_ct_job(struct bsg_job *job,
1011 			       struct zfcp_adapter *adapter)
1012 {
1013 	int ret;
1014 	struct zfcp_fsf_ct_els *ct = job->dd_data;
1015 	struct zfcp_fc_wka_port *wka_port;
1016 
1017 	wka_port = zfcp_fc_job_wka_port(job);
1018 	if (!wka_port)
1019 		return -EINVAL;
1020 
1021 	ret = zfcp_fc_wka_port_get(wka_port);
1022 	if (ret)
1023 		return ret;
1024 
1025 	ct->handler = zfcp_fc_ct_job_handler;
1026 	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
1027 	if (ret)
1028 		zfcp_fc_wka_port_put(wka_port);
1029 
1030 	return ret;
1031 }
1032 
1033 int zfcp_fc_exec_bsg_job(struct bsg_job *job)
1034 {
1035 	struct Scsi_Host *shost;
1036 	struct zfcp_adapter *adapter;
1037 	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
1038 	struct fc_bsg_request *bsg_request = job->request;
1039 	struct fc_rport *rport = fc_bsg_to_rport(job);
1040 
1041 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1042 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
1043 
1044 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
1045 		return -EINVAL;
1046 
1047 	ct_els->req = job->request_payload.sg_list;
1048 	ct_els->resp = job->reply_payload.sg_list;
1049 	ct_els->handler_data = job;
1050 
1051 	switch (bsg_request->msgcode) {
1052 	case FC_BSG_RPT_ELS:
1053 	case FC_BSG_HST_ELS_NOLOGIN:
1054 		return zfcp_fc_exec_els_job(job, adapter);
1055 	case FC_BSG_RPT_CT:
1056 	case FC_BSG_HST_CT:
1057 		return zfcp_fc_exec_ct_job(job, adapter);
1058 	default:
1059 		return -EINVAL;
1060 	}
1061 }
1062 
1063 int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
1064 {
1065 	/* hardware tracks timeout, reset bsg timeout to not interfere */
1066 	return -EAGAIN;
1067 }
1068 
1069 int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1070 {
1071 	struct zfcp_fc_wka_ports *wka_ports;
1072 
1073 	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1074 	if (!wka_ports)
1075 		return -ENOMEM;
1076 
1077 	adapter->gs = wka_ports;
1078 	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1079 	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1080 	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1081 	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1082 
1083 	return 0;
1084 }
1085 
1086 void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1087 {
1088 	kfree(adapter->gs);
1089 	adapter->gs = NULL;
1090 }
1091 
1092