xref: /linux/drivers/s390/scsi/zfcp_fc.c (revision d198b34f3855eee2571dda03eea75a09c7c31480)
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 	}
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 	/* port is good, unblock rport without going through erp */
525 	zfcp_scsi_schedule_rport_register(port);
526  out:
527 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
528 	put_device(&port->dev);
529 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
530 }
531 
532 static int zfcp_fc_adisc(struct zfcp_port *port)
533 {
534 	struct zfcp_fc_req *fc_req;
535 	struct zfcp_adapter *adapter = port->adapter;
536 	struct Scsi_Host *shost = adapter->scsi_host;
537 	int ret;
538 
539 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
540 	if (!fc_req)
541 		return -ENOMEM;
542 
543 	fc_req->ct_els.port = port;
544 	fc_req->ct_els.req = &fc_req->sg_req;
545 	fc_req->ct_els.resp = &fc_req->sg_rsp;
546 	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
547 		    sizeof(struct fc_els_adisc));
548 	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
549 		    sizeof(struct fc_els_adisc));
550 
551 	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
552 	fc_req->ct_els.handler_data = fc_req;
553 
554 	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
555 	   without FC-AL-2 capability, so we don't set it */
556 	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
557 	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
558 	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
559 	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
560 
561 	ret = zfcp_fsf_send_els(adapter, port->d_id, &fc_req->ct_els,
562 				ZFCP_FC_CTELS_TMO);
563 	if (ret)
564 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
565 
566 	return ret;
567 }
568 
569 void zfcp_fc_link_test_work(struct work_struct *work)
570 {
571 	struct zfcp_port *port =
572 		container_of(work, struct zfcp_port, test_link_work);
573 	int retval;
574 
575 	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
576 	get_device(&port->dev);
577 	port->rport_task = RPORT_DEL;
578 	zfcp_scsi_rport_work(&port->rport_work);
579 
580 	/* only issue one test command at one time per port */
581 	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
582 		goto out;
583 
584 	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
585 
586 	retval = zfcp_fc_adisc(port);
587 	if (retval == 0)
588 		return;
589 
590 	/* send of ADISC was not possible */
591 	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
592 	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
593 
594 out:
595 	put_device(&port->dev);
596 }
597 
598 /**
599  * zfcp_fc_test_link - lightweight link test procedure
600  * @port: port to be tested
601  *
602  * Test status of a link to a remote port using the ELS command ADISC.
603  * If there is a problem with the remote port, error recovery steps
604  * will be triggered.
605  */
606 void zfcp_fc_test_link(struct zfcp_port *port)
607 {
608 	get_device(&port->dev);
609 	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
610 		put_device(&port->dev);
611 }
612 
613 /**
614  * zfcp_fc_sg_free_table - free memory used by scatterlists
615  * @sg: pointer to scatterlist
616  * @count: number of scatterlist which are to be free'ed
617  * the scatterlist are expected to reference pages always
618  */
619 static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
620 {
621 	int i;
622 
623 	for (i = 0; i < count; i++, sg = sg_next(sg))
624 		if (sg)
625 			free_page((unsigned long) sg_virt(sg));
626 		else
627 			break;
628 }
629 
630 /**
631  * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
632  * @sg: pointer to struct scatterlist
633  * @count: number of scatterlists which should be assigned with buffers
634  * of size page
635  *
636  * Returns: 0 on success, -ENOMEM otherwise
637  */
638 static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
639 {
640 	void *addr;
641 	int i;
642 
643 	sg_init_table(sg, count);
644 	for (i = 0; i < count; i++, sg = sg_next(sg)) {
645 		addr = (void *) get_zeroed_page(GFP_KERNEL);
646 		if (!addr) {
647 			zfcp_fc_sg_free_table(sg, i);
648 			return -ENOMEM;
649 		}
650 		sg_set_buf(sg, addr, PAGE_SIZE);
651 	}
652 	return 0;
653 }
654 
655 static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
656 {
657 	struct zfcp_fc_req *fc_req;
658 
659 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
660 	if (!fc_req)
661 		return NULL;
662 
663 	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
664 		kmem_cache_free(zfcp_fc_req_cache, fc_req);
665 		return NULL;
666 	}
667 
668 	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
669 		    sizeof(struct zfcp_fc_gpn_ft_req));
670 
671 	return fc_req;
672 }
673 
674 static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
675 			       struct zfcp_adapter *adapter, int max_bytes)
676 {
677 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
678 	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
679 	DECLARE_COMPLETION_ONSTACK(completion);
680 	int ret;
681 
682 	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
683 	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
684 
685 	ct_els->handler = zfcp_fc_complete;
686 	ct_els->handler_data = &completion;
687 	ct_els->req = &fc_req->sg_req;
688 	ct_els->resp = &fc_req->sg_rsp;
689 
690 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
691 			       ZFCP_FC_CTELS_TMO);
692 	if (!ret)
693 		wait_for_completion(&completion);
694 	return ret;
695 }
696 
697 static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
698 {
699 	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
700 		return;
701 
702 	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
703 
704 	if ((port->supported_classes != 0) ||
705 	    !list_empty(&port->unit_list))
706 		return;
707 
708 	list_move_tail(&port->list, lh);
709 }
710 
711 static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
712 			       struct zfcp_adapter *adapter, int max_entries)
713 {
714 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
715 	struct scatterlist *sg = &fc_req->sg_rsp;
716 	struct fc_ct_hdr *hdr = sg_virt(sg);
717 	struct fc_gpn_ft_resp *acc = sg_virt(sg);
718 	struct zfcp_port *port, *tmp;
719 	unsigned long flags;
720 	LIST_HEAD(remove_lh);
721 	u32 d_id;
722 	int ret = 0, x, last = 0;
723 
724 	if (ct_els->status)
725 		return -EIO;
726 
727 	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
728 		if (hdr->ct_reason == FC_FS_RJT_UNABL)
729 			return -EAGAIN; /* might be a temporary condition */
730 		return -EIO;
731 	}
732 
733 	if (hdr->ct_mr_size) {
734 		dev_warn(&adapter->ccw_device->dev,
735 			 "The name server reported %d words residual data\n",
736 			 hdr->ct_mr_size);
737 		return -E2BIG;
738 	}
739 
740 	/* first entry is the header */
741 	for (x = 1; x < max_entries && !last; x++) {
742 		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
743 			acc++;
744 		else
745 			acc = sg_virt(++sg);
746 
747 		last = acc->fp_flags & FC_NS_FID_LAST;
748 		d_id = ntoh24(acc->fp_fid);
749 
750 		/* don't attach ports with a well known address */
751 		if (d_id >= FC_FID_WELL_KNOWN_BASE)
752 			continue;
753 		/* skip the adapter's port and known remote ports */
754 		if (be64_to_cpu(acc->fp_wwpn) ==
755 		    fc_host_port_name(adapter->scsi_host))
756 			continue;
757 
758 		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
759 					 ZFCP_STATUS_COMMON_NOESC, d_id);
760 		if (!IS_ERR(port))
761 			zfcp_erp_port_reopen(port, 0, "fcegpf1");
762 		else if (PTR_ERR(port) != -EEXIST)
763 			ret = PTR_ERR(port);
764 	}
765 
766 	zfcp_erp_wait(adapter);
767 	write_lock_irqsave(&adapter->port_list_lock, flags);
768 	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
769 		zfcp_fc_validate_port(port, &remove_lh);
770 	write_unlock_irqrestore(&adapter->port_list_lock, flags);
771 
772 	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
773 		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
774 		device_unregister(&port->dev);
775 	}
776 
777 	return ret;
778 }
779 
780 /**
781  * zfcp_fc_scan_ports - scan remote ports and attach new ports
782  * @work: reference to scheduled work
783  */
784 void zfcp_fc_scan_ports(struct work_struct *work)
785 {
786 	struct delayed_work *dw = to_delayed_work(work);
787 	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
788 						    scan_work);
789 	int ret, i;
790 	struct zfcp_fc_req *fc_req;
791 	int chain, max_entries, buf_num, max_bytes;
792 
793 	zfcp_fc_port_scan_time(adapter);
794 
795 	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
796 	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
797 	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
798 	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
799 
800 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
801 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
802 		return;
803 
804 	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
805 		return;
806 
807 	fc_req = zfcp_fc_alloc_sg_env(buf_num);
808 	if (!fc_req)
809 		goto out;
810 
811 	for (i = 0; i < 3; i++) {
812 		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
813 		if (!ret) {
814 			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
815 			if (ret == -EAGAIN)
816 				ssleep(1);
817 			else
818 				break;
819 		}
820 	}
821 	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
822 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
823 out:
824 	zfcp_fc_wka_port_put(&adapter->gs->ds);
825 }
826 
827 static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
828 			struct zfcp_fc_req *fc_req)
829 {
830 	DECLARE_COMPLETION_ONSTACK(completion);
831 	char devno[] = "DEVNO:";
832 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
833 	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
834 	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
835 	int ret;
836 
837 	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
838 			   FC_SYMBOLIC_NAME_SIZE);
839 	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
840 
841 	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
842 	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
843 
844 	ct_els->handler = zfcp_fc_complete;
845 	ct_els->handler_data = &completion;
846 	ct_els->req = &fc_req->sg_req;
847 	ct_els->resp = &fc_req->sg_rsp;
848 
849 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
850 			       ZFCP_FC_CTELS_TMO);
851 	if (ret)
852 		return ret;
853 
854 	wait_for_completion(&completion);
855 	if (ct_els->status)
856 		return ct_els->status;
857 
858 	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
859 	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
860 		snprintf(fc_host_symbolic_name(adapter->scsi_host),
861 			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
862 			 gspn_rsp->gspn.fp_name, devno,
863 			 dev_name(&adapter->ccw_device->dev),
864 			 init_utsname()->nodename);
865 	else
866 		strlcpy(fc_host_symbolic_name(adapter->scsi_host),
867 			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
868 
869 	return 0;
870 }
871 
872 static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
873 			 struct zfcp_fc_req *fc_req)
874 {
875 	DECLARE_COMPLETION_ONSTACK(completion);
876 	struct Scsi_Host *shost = adapter->scsi_host;
877 	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
878 	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
879 	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
880 	int ret, len;
881 
882 	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
883 			   FC_SYMBOLIC_NAME_SIZE);
884 	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
885 	len = strlcpy(rspn_req->rspn.fr_name, fc_host_symbolic_name(shost),
886 		      FC_SYMBOLIC_NAME_SIZE);
887 	rspn_req->rspn.fr_name_len = len;
888 
889 	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
890 	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
891 
892 	ct_els->handler = zfcp_fc_complete;
893 	ct_els->handler_data = &completion;
894 	ct_els->req = &fc_req->sg_req;
895 	ct_els->resp = &fc_req->sg_rsp;
896 
897 	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
898 			       ZFCP_FC_CTELS_TMO);
899 	if (!ret)
900 		wait_for_completion(&completion);
901 }
902 
903 /**
904  * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
905  * @work: ns_up_work of the adapter where to update the symbolic port name
906  *
907  * Retrieve the current symbolic port name that may have been set by
908  * the hardware using the GSPN request and update the fc_host
909  * symbolic_name sysfs attribute. When running in NPIV mode (and hence
910  * the port name is unique for this system), update the symbolic port
911  * name to add Linux specific information and update the FC nameserver
912  * using the RSPN request.
913  */
914 void zfcp_fc_sym_name_update(struct work_struct *work)
915 {
916 	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
917 						    ns_up_work);
918 	int ret;
919 	struct zfcp_fc_req *fc_req;
920 
921 	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
922 	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
923 		return;
924 
925 	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
926 	if (!fc_req)
927 		return;
928 
929 	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
930 	if (ret)
931 		goto out_free;
932 
933 	ret = zfcp_fc_gspn(adapter, fc_req);
934 	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
935 		goto out_ds_put;
936 
937 	memset(fc_req, 0, sizeof(*fc_req));
938 	zfcp_fc_rspn(adapter, fc_req);
939 
940 out_ds_put:
941 	zfcp_fc_wka_port_put(&adapter->gs->ds);
942 out_free:
943 	kmem_cache_free(zfcp_fc_req_cache, fc_req);
944 }
945 
946 static void zfcp_fc_ct_els_job_handler(void *data)
947 {
948 	struct bsg_job *job = data;
949 	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
950 	struct fc_bsg_reply *jr = job->reply;
951 
952 	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
953 	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
954 	jr->result = zfcp_ct_els->status ? -EIO : 0;
955 	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
956 }
957 
958 static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
959 {
960 	u32 preamble_word1;
961 	u8 gs_type;
962 	struct zfcp_adapter *adapter;
963 	struct fc_bsg_request *bsg_request = job->request;
964 	struct fc_rport *rport = fc_bsg_to_rport(job);
965 	struct Scsi_Host *shost;
966 
967 	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
968 	gs_type = (preamble_word1 & 0xff000000) >> 24;
969 
970 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
971 	adapter = (struct zfcp_adapter *) shost->hostdata[0];
972 
973 	switch (gs_type) {
974 	case FC_FST_ALIAS:
975 		return &adapter->gs->as;
976 	case FC_FST_MGMT:
977 		return &adapter->gs->ms;
978 	case FC_FST_TIME:
979 		return &adapter->gs->ts;
980 		break;
981 	case FC_FST_DIR:
982 		return &adapter->gs->ds;
983 		break;
984 	default:
985 		return NULL;
986 	}
987 }
988 
989 static void zfcp_fc_ct_job_handler(void *data)
990 {
991 	struct bsg_job *job = data;
992 	struct zfcp_fc_wka_port *wka_port;
993 
994 	wka_port = zfcp_fc_job_wka_port(job);
995 	zfcp_fc_wka_port_put(wka_port);
996 
997 	zfcp_fc_ct_els_job_handler(data);
998 }
999 
1000 static int zfcp_fc_exec_els_job(struct bsg_job *job,
1001 				struct zfcp_adapter *adapter)
1002 {
1003 	struct zfcp_fsf_ct_els *els = job->dd_data;
1004 	struct fc_rport *rport = fc_bsg_to_rport(job);
1005 	struct fc_bsg_request *bsg_request = job->request;
1006 	struct zfcp_port *port;
1007 	u32 d_id;
1008 
1009 	if (rport) {
1010 		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
1011 		if (!port)
1012 			return -EINVAL;
1013 
1014 		d_id = port->d_id;
1015 		put_device(&port->dev);
1016 	} else
1017 		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);
1018 
1019 	els->handler = zfcp_fc_ct_els_job_handler;
1020 	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
1021 }
1022 
1023 static int zfcp_fc_exec_ct_job(struct bsg_job *job,
1024 			       struct zfcp_adapter *adapter)
1025 {
1026 	int ret;
1027 	struct zfcp_fsf_ct_els *ct = job->dd_data;
1028 	struct zfcp_fc_wka_port *wka_port;
1029 
1030 	wka_port = zfcp_fc_job_wka_port(job);
1031 	if (!wka_port)
1032 		return -EINVAL;
1033 
1034 	ret = zfcp_fc_wka_port_get(wka_port);
1035 	if (ret)
1036 		return ret;
1037 
1038 	ct->handler = zfcp_fc_ct_job_handler;
1039 	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
1040 	if (ret)
1041 		zfcp_fc_wka_port_put(wka_port);
1042 
1043 	return ret;
1044 }
1045 
1046 int zfcp_fc_exec_bsg_job(struct bsg_job *job)
1047 {
1048 	struct Scsi_Host *shost;
1049 	struct zfcp_adapter *adapter;
1050 	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
1051 	struct fc_bsg_request *bsg_request = job->request;
1052 	struct fc_rport *rport = fc_bsg_to_rport(job);
1053 
1054 	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1055 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
1056 
1057 	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
1058 		return -EINVAL;
1059 
1060 	ct_els->req = job->request_payload.sg_list;
1061 	ct_els->resp = job->reply_payload.sg_list;
1062 	ct_els->handler_data = job;
1063 
1064 	switch (bsg_request->msgcode) {
1065 	case FC_BSG_RPT_ELS:
1066 	case FC_BSG_HST_ELS_NOLOGIN:
1067 		return zfcp_fc_exec_els_job(job, adapter);
1068 	case FC_BSG_RPT_CT:
1069 	case FC_BSG_HST_CT:
1070 		return zfcp_fc_exec_ct_job(job, adapter);
1071 	default:
1072 		return -EINVAL;
1073 	}
1074 }
1075 
1076 int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
1077 {
1078 	/* hardware tracks timeout, reset bsg timeout to not interfere */
1079 	return -EAGAIN;
1080 }
1081 
1082 int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1083 {
1084 	struct zfcp_fc_wka_ports *wka_ports;
1085 
1086 	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1087 	if (!wka_ports)
1088 		return -ENOMEM;
1089 
1090 	adapter->gs = wka_ports;
1091 	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1092 	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1093 	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1094 	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1095 
1096 	return 0;
1097 }
1098 
1099 void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1100 {
1101 	kfree(adapter->gs);
1102 	adapter->gs = NULL;
1103 }
1104 
1105