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
23struct kmem_cache *zfcp_fc_req_cache;
24
25static 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
32static bool no_auto_port_rescan;
33module_param(no_auto_port_rescan, bool, 0600);
34MODULE_PARM_DESC(no_auto_port_rescan,
35		 "no automatic port_rescan (default off)");
36
37static unsigned int port_scan_backoff = 500;
38module_param(port_scan_backoff, uint, 0600);
39MODULE_PARM_DESC(port_scan_backoff,
40	"upper limit of port scan random backoff in msecs (default 500)");
41
42static unsigned int port_scan_ratelimit = 60000;
43module_param(port_scan_ratelimit, uint, 0600);
44MODULE_PARM_DESC(port_scan_ratelimit,
45	"minimum interval between port scans in msecs (default 60000)");
46
47unsigned int zfcp_fc_port_scan_backoff(void)
48{
49	if (!port_scan_backoff)
50		return 0;
51	return get_random_u32_below(port_scan_backoff);
52}
53
54static 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
62static 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
79void 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
87void 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 */
99void 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 */
127void 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
146static int zfcp_fc_wka_port_get(struct zfcp_fc_wka_port *wka_port)
147{
148	int ret = -EIO;
149
150	if (mutex_lock_interruptible(&wka_port->mutex))
151		return -ERESTARTSYS;
152
153	if (wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE ||
154	    wka_port->status == ZFCP_FC_WKA_PORT_CLOSING) {
155		wka_port->status = ZFCP_FC_WKA_PORT_OPENING;
156		if (zfcp_fsf_open_wka_port(wka_port)) {
157			/* could not even send request, nothing to wait for */
158			wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
159			goto out;
160		}
161	}
162
163	wait_event(wka_port->opened,
164		   wka_port->status == ZFCP_FC_WKA_PORT_ONLINE ||
165		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
166
167	if (wka_port->status == ZFCP_FC_WKA_PORT_ONLINE) {
168		atomic_inc(&wka_port->refcount);
169		ret = 0;
170		goto out;
171	}
172out:
173	mutex_unlock(&wka_port->mutex);
174	return ret;
175}
176
177static void zfcp_fc_wka_port_offline(struct work_struct *work)
178{
179	struct delayed_work *dw = to_delayed_work(work);
180	struct zfcp_fc_wka_port *wka_port =
181			container_of(dw, struct zfcp_fc_wka_port, work);
182
183	mutex_lock(&wka_port->mutex);
184	if ((atomic_read(&wka_port->refcount) != 0) ||
185	    (wka_port->status != ZFCP_FC_WKA_PORT_ONLINE))
186		goto out;
187
188	wka_port->status = ZFCP_FC_WKA_PORT_CLOSING;
189	if (zfcp_fsf_close_wka_port(wka_port)) {
190		/* could not even send request, nothing to wait for */
191		wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
192		goto out;
193	}
194	wait_event(wka_port->closed,
195		   wka_port->status == ZFCP_FC_WKA_PORT_OFFLINE);
196out:
197	mutex_unlock(&wka_port->mutex);
198}
199
200static void zfcp_fc_wka_port_put(struct zfcp_fc_wka_port *wka_port)
201{
202	if (atomic_dec_return(&wka_port->refcount) != 0)
203		return;
204	/* wait 10 milliseconds, other reqs might pop in */
205	queue_delayed_work(wka_port->adapter->work_queue, &wka_port->work,
206			   msecs_to_jiffies(10));
207}
208
209static void zfcp_fc_wka_port_init(struct zfcp_fc_wka_port *wka_port, u32 d_id,
210				  struct zfcp_adapter *adapter)
211{
212	init_waitqueue_head(&wka_port->opened);
213	init_waitqueue_head(&wka_port->closed);
214
215	wka_port->adapter = adapter;
216	wka_port->d_id = d_id;
217
218	wka_port->status = ZFCP_FC_WKA_PORT_OFFLINE;
219	atomic_set(&wka_port->refcount, 0);
220	mutex_init(&wka_port->mutex);
221	INIT_DELAYED_WORK(&wka_port->work, zfcp_fc_wka_port_offline);
222}
223
224static void zfcp_fc_wka_port_force_offline(struct zfcp_fc_wka_port *wka)
225{
226	cancel_delayed_work_sync(&wka->work);
227	mutex_lock(&wka->mutex);
228	wka->status = ZFCP_FC_WKA_PORT_OFFLINE;
229	mutex_unlock(&wka->mutex);
230}
231
232void zfcp_fc_wka_ports_force_offline(struct zfcp_fc_wka_ports *gs)
233{
234	if (!gs)
235		return;
236	zfcp_fc_wka_port_force_offline(&gs->ms);
237	zfcp_fc_wka_port_force_offline(&gs->ts);
238	zfcp_fc_wka_port_force_offline(&gs->ds);
239	zfcp_fc_wka_port_force_offline(&gs->as);
240}
241
242static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
243				   struct fc_els_rscn_page *page)
244{
245	unsigned long flags;
246	struct zfcp_adapter *adapter = fsf_req->adapter;
247	struct zfcp_port *port;
248
249	read_lock_irqsave(&adapter->port_list_lock, flags);
250	list_for_each_entry(port, &adapter->port_list, list) {
251		if ((port->d_id & range) == (ntoh24(page->rscn_fid) & range))
252			zfcp_fc_test_link(port);
253	}
254	read_unlock_irqrestore(&adapter->port_list_lock, flags);
255}
256
257static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
258{
259	struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
260	struct zfcp_adapter *adapter = fsf_req->adapter;
261	struct fc_els_rscn *head;
262	struct fc_els_rscn_page *page;
263	u16 i;
264	u16 no_entries;
265	unsigned int afmt;
266
267	head = (struct fc_els_rscn *) status_buffer->payload.data;
268	page = (struct fc_els_rscn_page *) head;
269
270	/* see FC-FS */
271	no_entries = be16_to_cpu(head->rscn_plen) /
272		sizeof(struct fc_els_rscn_page);
273
274	if (no_entries > 1) {
275		/* handle failed ports */
276		unsigned long flags;
277		struct zfcp_port *port;
278
279		read_lock_irqsave(&adapter->port_list_lock, flags);
280		list_for_each_entry(port, &adapter->port_list, list) {
281			if (port->d_id)
282				continue;
283			zfcp_erp_port_reopen(port,
284					     ZFCP_STATUS_COMMON_ERP_FAILED,
285					     "fcrscn1");
286		}
287		read_unlock_irqrestore(&adapter->port_list_lock, flags);
288	}
289
290	for (i = 1; i < no_entries; i++) {
291		/* skip head and start with 1st element */
292		page++;
293		afmt = page->rscn_page_flags & ELS_RSCN_ADDR_FMT_MASK;
294		_zfcp_fc_incoming_rscn(fsf_req, zfcp_fc_rscn_range_mask[afmt],
295				       page);
296		zfcp_fc_enqueue_event(fsf_req->adapter, FCH_EVT_RSCN,
297				      *(u32 *)page);
298	}
299	zfcp_fc_conditional_port_scan(fsf_req->adapter);
300}
301
302static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
303{
304	unsigned long flags;
305	struct zfcp_adapter *adapter = req->adapter;
306	struct zfcp_port *port;
307
308	read_lock_irqsave(&adapter->port_list_lock, flags);
309	list_for_each_entry(port, &adapter->port_list, list)
310		if (port->wwpn == wwpn) {
311			zfcp_erp_port_forced_reopen(port, 0, "fciwwp1");
312			break;
313		}
314	read_unlock_irqrestore(&adapter->port_list_lock, flags);
315}
316
317static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
318{
319	struct fsf_status_read_buffer *status_buffer;
320	struct fc_els_flogi *plogi;
321
322	status_buffer = (struct fsf_status_read_buffer *) req->data;
323	plogi = (struct fc_els_flogi *) status_buffer->payload.data;
324	zfcp_fc_incoming_wwpn(req, be64_to_cpu(plogi->fl_wwpn));
325}
326
327static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
328{
329	struct fsf_status_read_buffer *status_buffer =
330		(struct fsf_status_read_buffer *)req->data;
331	struct fc_els_logo *logo =
332		(struct fc_els_logo *) status_buffer->payload.data;
333
334	zfcp_fc_incoming_wwpn(req, be64_to_cpu(logo->fl_n_port_wwn));
335}
336
337/**
338 * zfcp_fc_incoming_els - handle incoming ELS
339 * @fsf_req: request which contains incoming ELS
340 */
341void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
342{
343	struct fsf_status_read_buffer *status_buffer =
344		(struct fsf_status_read_buffer *) fsf_req->data;
345	unsigned int els_type = status_buffer->payload.data[0];
346
347	zfcp_dbf_san_in_els("fciels1", fsf_req);
348	if (els_type == ELS_PLOGI)
349		zfcp_fc_incoming_plogi(fsf_req);
350	else if (els_type == ELS_LOGO)
351		zfcp_fc_incoming_logo(fsf_req);
352	else if (els_type == ELS_RSCN)
353		zfcp_fc_incoming_rscn(fsf_req);
354}
355
356static void zfcp_fc_ns_gid_pn_eval(struct zfcp_fc_req *fc_req)
357{
358	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
359	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
360
361	if (ct_els->status)
362		return;
363	if (gid_pn_rsp->ct_hdr.ct_cmd != cpu_to_be16(FC_FS_ACC))
364		return;
365
366	/* looks like a valid d_id */
367	ct_els->port->d_id = ntoh24(gid_pn_rsp->gid_pn.fp_fid);
368}
369
370static void zfcp_fc_complete(void *data)
371{
372	complete(data);
373}
374
375static void zfcp_fc_ct_ns_init(struct fc_ct_hdr *ct_hdr, u16 cmd, u16 mr_size)
376{
377	ct_hdr->ct_rev = FC_CT_REV;
378	ct_hdr->ct_fs_type = FC_FST_DIR;
379	ct_hdr->ct_fs_subtype = FC_NS_SUBTYPE;
380	ct_hdr->ct_cmd = cpu_to_be16(cmd);
381	ct_hdr->ct_mr_size = cpu_to_be16(mr_size / 4);
382}
383
384static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
385				     struct zfcp_fc_req *fc_req)
386{
387	struct zfcp_adapter *adapter = port->adapter;
388	DECLARE_COMPLETION_ONSTACK(completion);
389	struct zfcp_fc_gid_pn_req *gid_pn_req = &fc_req->u.gid_pn.req;
390	struct zfcp_fc_gid_pn_rsp *gid_pn_rsp = &fc_req->u.gid_pn.rsp;
391	int ret;
392
393	/* setup parameters for send generic command */
394	fc_req->ct_els.port = port;
395	fc_req->ct_els.handler = zfcp_fc_complete;
396	fc_req->ct_els.handler_data = &completion;
397	fc_req->ct_els.req = &fc_req->sg_req;
398	fc_req->ct_els.resp = &fc_req->sg_rsp;
399	sg_init_one(&fc_req->sg_req, gid_pn_req, sizeof(*gid_pn_req));
400	sg_init_one(&fc_req->sg_rsp, gid_pn_rsp, sizeof(*gid_pn_rsp));
401
402	zfcp_fc_ct_ns_init(&gid_pn_req->ct_hdr,
403			   FC_NS_GID_PN, ZFCP_FC_CT_SIZE_PAGE);
404	gid_pn_req->gid_pn.fn_wwpn = cpu_to_be64(port->wwpn);
405
406	ret = zfcp_fsf_send_ct(&adapter->gs->ds, &fc_req->ct_els,
407			       adapter->pool.gid_pn_req,
408			       ZFCP_FC_CTELS_TMO);
409	if (!ret) {
410		wait_for_completion(&completion);
411		zfcp_fc_ns_gid_pn_eval(fc_req);
412	}
413	return ret;
414}
415
416/**
417 * zfcp_fc_ns_gid_pn - initiate GID_PN nameserver request
418 * @port: port where GID_PN request is needed
419 * return: -ENOMEM on error, 0 otherwise
420 */
421static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
422{
423	int ret;
424	struct zfcp_fc_req *fc_req;
425	struct zfcp_adapter *adapter = port->adapter;
426
427	fc_req = mempool_alloc(adapter->pool.gid_pn, GFP_ATOMIC);
428	if (!fc_req)
429		return -ENOMEM;
430
431	memset(fc_req, 0, sizeof(*fc_req));
432
433	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
434	if (ret)
435		goto out;
436
437	ret = zfcp_fc_ns_gid_pn_request(port, fc_req);
438
439	zfcp_fc_wka_port_put(&adapter->gs->ds);
440out:
441	mempool_free(fc_req, adapter->pool.gid_pn);
442	return ret;
443}
444
445void zfcp_fc_port_did_lookup(struct work_struct *work)
446{
447	int ret;
448	struct zfcp_port *port = container_of(work, struct zfcp_port,
449					      gid_pn_work);
450
451	set_worker_desc("zgidpn%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
452	ret = zfcp_fc_ns_gid_pn(port);
453	if (ret) {
454		/* could not issue gid_pn for some reason */
455		zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1");
456		goto out;
457	}
458
459	if (!port->d_id) {
460		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
461		goto out;
462	}
463
464	zfcp_erp_port_reopen(port, 0, "fcgpn_3");
465out:
466	put_device(&port->dev);
467}
468
469/**
470 * zfcp_fc_trigger_did_lookup - trigger the d_id lookup using a GID_PN request
471 * @port: The zfcp_port to lookup the d_id for.
472 */
473void zfcp_fc_trigger_did_lookup(struct zfcp_port *port)
474{
475	get_device(&port->dev);
476	if (!queue_work(port->adapter->work_queue, &port->gid_pn_work))
477		put_device(&port->dev);
478}
479
480/**
481 * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
482 * @port: zfcp_port structure
483 * @plogi: plogi payload
484 *
485 * Evaluate PLOGI playload and copy important fields into zfcp_port structure
486 */
487void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fc_els_flogi *plogi)
488{
489	if (be64_to_cpu(plogi->fl_wwpn) != port->wwpn) {
490		port->d_id = 0;
491		dev_warn(&port->adapter->ccw_device->dev,
492			 "A port opened with WWPN 0x%016Lx returned data that "
493			 "identifies it as WWPN 0x%016Lx\n",
494			 (unsigned long long) port->wwpn,
495			 (unsigned long long) be64_to_cpu(plogi->fl_wwpn));
496		return;
497	}
498
499	port->wwnn = be64_to_cpu(plogi->fl_wwnn);
500	port->maxframe_size = be16_to_cpu(plogi->fl_csp.sp_bb_data);
501
502	if (plogi->fl_cssp[0].cp_class & cpu_to_be16(FC_CPC_VALID))
503		port->supported_classes |= FC_COS_CLASS1;
504	if (plogi->fl_cssp[1].cp_class & cpu_to_be16(FC_CPC_VALID))
505		port->supported_classes |= FC_COS_CLASS2;
506	if (plogi->fl_cssp[2].cp_class & cpu_to_be16(FC_CPC_VALID))
507		port->supported_classes |= FC_COS_CLASS3;
508	if (plogi->fl_cssp[3].cp_class & cpu_to_be16(FC_CPC_VALID))
509		port->supported_classes |= FC_COS_CLASS4;
510}
511
512static void zfcp_fc_adisc_handler(void *data)
513{
514	struct zfcp_fc_req *fc_req = data;
515	struct zfcp_port *port = fc_req->ct_els.port;
516	struct fc_els_adisc *adisc_resp = &fc_req->u.adisc.rsp;
517
518	if (fc_req->ct_els.status) {
519		/* request rejected or timed out */
520		zfcp_erp_port_forced_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
521					    "fcadh_1");
522		goto out;
523	}
524
525	if (!port->wwnn)
526		port->wwnn = be64_to_cpu(adisc_resp->adisc_wwnn);
527
528	if ((port->wwpn != be64_to_cpu(adisc_resp->adisc_wwpn)) ||
529	    !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
530		zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
531				     "fcadh_2");
532		goto out;
533	}
534
535	/* re-init to undo drop from zfcp_fc_adisc() */
536	port->d_id = ntoh24(adisc_resp->adisc_port_id);
537	/* port is still good, nothing to do */
538 out:
539	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
540	put_device(&port->dev);
541	kmem_cache_free(zfcp_fc_req_cache, fc_req);
542}
543
544static int zfcp_fc_adisc(struct zfcp_port *port)
545{
546	struct zfcp_fc_req *fc_req;
547	struct zfcp_adapter *adapter = port->adapter;
548	struct Scsi_Host *shost = adapter->scsi_host;
549	u32 d_id;
550	int ret;
551
552	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_ATOMIC);
553	if (!fc_req)
554		return -ENOMEM;
555
556	fc_req->ct_els.port = port;
557	fc_req->ct_els.req = &fc_req->sg_req;
558	fc_req->ct_els.resp = &fc_req->sg_rsp;
559	sg_init_one(&fc_req->sg_req, &fc_req->u.adisc.req,
560		    sizeof(struct fc_els_adisc));
561	sg_init_one(&fc_req->sg_rsp, &fc_req->u.adisc.rsp,
562		    sizeof(struct fc_els_adisc));
563
564	fc_req->ct_els.handler = zfcp_fc_adisc_handler;
565	fc_req->ct_els.handler_data = fc_req;
566
567	/* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
568	   without FC-AL-2 capability, so we don't set it */
569	fc_req->u.adisc.req.adisc_wwpn = cpu_to_be64(fc_host_port_name(shost));
570	fc_req->u.adisc.req.adisc_wwnn = cpu_to_be64(fc_host_node_name(shost));
571	fc_req->u.adisc.req.adisc_cmd = ELS_ADISC;
572	hton24(fc_req->u.adisc.req.adisc_port_id, fc_host_port_id(shost));
573
574	d_id = port->d_id; /* remember as destination for send els below */
575	/*
576	 * Force fresh GID_PN lookup on next port recovery.
577	 * Must happen after request setup and before sending request,
578	 * to prevent race with port->d_id re-init in zfcp_fc_adisc_handler().
579	 */
580	port->d_id = 0;
581
582	ret = zfcp_fsf_send_els(adapter, d_id, &fc_req->ct_els,
583				ZFCP_FC_CTELS_TMO);
584	if (ret)
585		kmem_cache_free(zfcp_fc_req_cache, fc_req);
586
587	return ret;
588}
589
590void zfcp_fc_link_test_work(struct work_struct *work)
591{
592	struct zfcp_port *port =
593		container_of(work, struct zfcp_port, test_link_work);
594	int retval;
595
596	set_worker_desc("zadisc%16llx", port->wwpn); /* < WORKER_DESC_LEN=24 */
597
598	/* only issue one test command at one time per port */
599	if (atomic_read(&port->status) & ZFCP_STATUS_PORT_LINK_TEST)
600		goto out;
601
602	atomic_or(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
603
604	retval = zfcp_fc_adisc(port);
605	if (retval == 0)
606		return;
607
608	/* send of ADISC was not possible */
609	atomic_andnot(ZFCP_STATUS_PORT_LINK_TEST, &port->status);
610	zfcp_erp_port_forced_reopen(port, 0, "fcltwk1");
611
612out:
613	put_device(&port->dev);
614}
615
616/**
617 * zfcp_fc_test_link - lightweight link test procedure
618 * @port: port to be tested
619 *
620 * Test status of a link to a remote port using the ELS command ADISC.
621 * If there is a problem with the remote port, error recovery steps
622 * will be triggered.
623 */
624void zfcp_fc_test_link(struct zfcp_port *port)
625{
626	get_device(&port->dev);
627	if (!queue_work(port->adapter->work_queue, &port->test_link_work))
628		put_device(&port->dev);
629}
630
631/**
632 * zfcp_fc_sg_free_table - free memory used by scatterlists
633 * @sg: pointer to scatterlist
634 * @count: number of scatterlist which are to be free'ed
635 * the scatterlist are expected to reference pages always
636 */
637static void zfcp_fc_sg_free_table(struct scatterlist *sg, int count)
638{
639	int i;
640
641	for (i = 0; i < count; i++, sg = sg_next(sg))
642		if (sg)
643			free_page((unsigned long) sg_virt(sg));
644		else
645			break;
646}
647
648/**
649 * zfcp_fc_sg_setup_table - init scatterlist and allocate, assign buffers
650 * @sg: pointer to struct scatterlist
651 * @count: number of scatterlists which should be assigned with buffers
652 * of size page
653 *
654 * Returns: 0 on success, -ENOMEM otherwise
655 */
656static int zfcp_fc_sg_setup_table(struct scatterlist *sg, int count)
657{
658	void *addr;
659	int i;
660
661	sg_init_table(sg, count);
662	for (i = 0; i < count; i++, sg = sg_next(sg)) {
663		addr = (void *) get_zeroed_page(GFP_KERNEL);
664		if (!addr) {
665			zfcp_fc_sg_free_table(sg, i);
666			return -ENOMEM;
667		}
668		sg_set_buf(sg, addr, PAGE_SIZE);
669	}
670	return 0;
671}
672
673static struct zfcp_fc_req *zfcp_fc_alloc_sg_env(int buf_num)
674{
675	struct zfcp_fc_req *fc_req;
676
677	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
678	if (!fc_req)
679		return NULL;
680
681	if (zfcp_fc_sg_setup_table(&fc_req->sg_rsp, buf_num)) {
682		kmem_cache_free(zfcp_fc_req_cache, fc_req);
683		return NULL;
684	}
685
686	sg_init_one(&fc_req->sg_req, &fc_req->u.gpn_ft.req,
687		    sizeof(struct zfcp_fc_gpn_ft_req));
688
689	return fc_req;
690}
691
692static int zfcp_fc_send_gpn_ft(struct zfcp_fc_req *fc_req,
693			       struct zfcp_adapter *adapter, int max_bytes)
694{
695	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
696	struct zfcp_fc_gpn_ft_req *req = &fc_req->u.gpn_ft.req;
697	DECLARE_COMPLETION_ONSTACK(completion);
698	int ret;
699
700	zfcp_fc_ct_ns_init(&req->ct_hdr, FC_NS_GPN_FT, max_bytes);
701	req->gpn_ft.fn_fc4_type = FC_TYPE_FCP;
702
703	ct_els->handler = zfcp_fc_complete;
704	ct_els->handler_data = &completion;
705	ct_els->req = &fc_req->sg_req;
706	ct_els->resp = &fc_req->sg_rsp;
707
708	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
709			       ZFCP_FC_CTELS_TMO);
710	if (!ret)
711		wait_for_completion(&completion);
712	return ret;
713}
714
715static void zfcp_fc_validate_port(struct zfcp_port *port, struct list_head *lh)
716{
717	if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
718		return;
719
720	atomic_andnot(ZFCP_STATUS_COMMON_NOESC, &port->status);
721
722	if ((port->supported_classes != 0) ||
723	    !list_empty(&port->unit_list))
724		return;
725
726	list_move_tail(&port->list, lh);
727}
728
729static int zfcp_fc_eval_gpn_ft(struct zfcp_fc_req *fc_req,
730			       struct zfcp_adapter *adapter, int max_entries)
731{
732	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
733	struct scatterlist *sg = &fc_req->sg_rsp;
734	struct fc_ct_hdr *hdr = sg_virt(sg);
735	struct fc_gpn_ft_resp *acc = sg_virt(sg);
736	struct zfcp_port *port, *tmp;
737	unsigned long flags;
738	LIST_HEAD(remove_lh);
739	u32 d_id;
740	int ret = 0, x, last = 0;
741
742	if (ct_els->status)
743		return -EIO;
744
745	if (hdr->ct_cmd != cpu_to_be16(FC_FS_ACC)) {
746		if (hdr->ct_reason == FC_FS_RJT_UNABL)
747			return -EAGAIN; /* might be a temporary condition */
748		return -EIO;
749	}
750
751	if (hdr->ct_mr_size) {
752		dev_warn(&adapter->ccw_device->dev,
753			 "The name server reported %d words residual data\n",
754			 hdr->ct_mr_size);
755		return -E2BIG;
756	}
757
758	/* first entry is the header */
759	for (x = 1; x < max_entries && !last; x++) {
760		if (x % (ZFCP_FC_GPN_FT_ENT_PAGE + 1))
761			acc++;
762		else
763			acc = sg_virt(++sg);
764
765		last = acc->fp_flags & FC_NS_FID_LAST;
766		d_id = ntoh24(acc->fp_fid);
767
768		/* don't attach ports with a well known address */
769		if (d_id >= FC_FID_WELL_KNOWN_BASE)
770			continue;
771		/* skip the adapter's port and known remote ports */
772		if (be64_to_cpu(acc->fp_wwpn) ==
773		    fc_host_port_name(adapter->scsi_host))
774			continue;
775
776		port = zfcp_port_enqueue(adapter, be64_to_cpu(acc->fp_wwpn),
777					 ZFCP_STATUS_COMMON_NOESC, d_id);
778		if (!IS_ERR(port))
779			zfcp_erp_port_reopen(port, 0, "fcegpf1");
780		else if (PTR_ERR(port) != -EEXIST)
781			ret = PTR_ERR(port);
782	}
783
784	zfcp_erp_wait(adapter);
785	write_lock_irqsave(&adapter->port_list_lock, flags);
786	list_for_each_entry_safe(port, tmp, &adapter->port_list, list)
787		zfcp_fc_validate_port(port, &remove_lh);
788	write_unlock_irqrestore(&adapter->port_list_lock, flags);
789
790	list_for_each_entry_safe(port, tmp, &remove_lh, list) {
791		zfcp_erp_port_shutdown(port, 0, "fcegpf2");
792		device_unregister(&port->dev);
793	}
794
795	return ret;
796}
797
798/**
799 * zfcp_fc_scan_ports - scan remote ports and attach new ports
800 * @work: reference to scheduled work
801 */
802void zfcp_fc_scan_ports(struct work_struct *work)
803{
804	struct delayed_work *dw = to_delayed_work(work);
805	struct zfcp_adapter *adapter = container_of(dw, struct zfcp_adapter,
806						    scan_work);
807	int ret, i;
808	struct zfcp_fc_req *fc_req;
809	int chain, max_entries, buf_num, max_bytes;
810
811	zfcp_fc_port_scan_time(adapter);
812
813	chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
814	buf_num = chain ? ZFCP_FC_GPN_FT_NUM_BUFS : 1;
815	max_entries = chain ? ZFCP_FC_GPN_FT_MAX_ENT : ZFCP_FC_GPN_FT_ENT_PAGE;
816	max_bytes = chain ? ZFCP_FC_GPN_FT_MAX_SIZE : ZFCP_FC_CT_SIZE_PAGE;
817
818	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
819	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
820		return;
821
822	if (zfcp_fc_wka_port_get(&adapter->gs->ds))
823		return;
824
825	fc_req = zfcp_fc_alloc_sg_env(buf_num);
826	if (!fc_req)
827		goto out;
828
829	for (i = 0; i < 3; i++) {
830		ret = zfcp_fc_send_gpn_ft(fc_req, adapter, max_bytes);
831		if (!ret) {
832			ret = zfcp_fc_eval_gpn_ft(fc_req, adapter, max_entries);
833			if (ret == -EAGAIN)
834				ssleep(1);
835			else
836				break;
837		}
838	}
839	zfcp_fc_sg_free_table(&fc_req->sg_rsp, buf_num);
840	kmem_cache_free(zfcp_fc_req_cache, fc_req);
841out:
842	zfcp_fc_wka_port_put(&adapter->gs->ds);
843}
844
845static int zfcp_fc_gspn(struct zfcp_adapter *adapter,
846			struct zfcp_fc_req *fc_req)
847{
848	DECLARE_COMPLETION_ONSTACK(completion);
849	char devno[] = "DEVNO:";
850	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
851	struct zfcp_fc_gspn_req *gspn_req = &fc_req->u.gspn.req;
852	struct zfcp_fc_gspn_rsp *gspn_rsp = &fc_req->u.gspn.rsp;
853	int ret;
854
855	zfcp_fc_ct_ns_init(&gspn_req->ct_hdr, FC_NS_GSPN_ID,
856			   FC_SYMBOLIC_NAME_SIZE);
857	hton24(gspn_req->gspn.fp_fid, fc_host_port_id(adapter->scsi_host));
858
859	sg_init_one(&fc_req->sg_req, gspn_req, sizeof(*gspn_req));
860	sg_init_one(&fc_req->sg_rsp, gspn_rsp, sizeof(*gspn_rsp));
861
862	ct_els->handler = zfcp_fc_complete;
863	ct_els->handler_data = &completion;
864	ct_els->req = &fc_req->sg_req;
865	ct_els->resp = &fc_req->sg_rsp;
866
867	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
868			       ZFCP_FC_CTELS_TMO);
869	if (ret)
870		return ret;
871
872	wait_for_completion(&completion);
873	if (ct_els->status)
874		return ct_els->status;
875
876	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_NPIV &&
877	    !(strstr(gspn_rsp->gspn.fp_name, devno)))
878		snprintf(fc_host_symbolic_name(adapter->scsi_host),
879			 FC_SYMBOLIC_NAME_SIZE, "%s%s %s NAME: %s",
880			 gspn_rsp->gspn.fp_name, devno,
881			 dev_name(&adapter->ccw_device->dev),
882			 init_utsname()->nodename);
883	else
884		strscpy(fc_host_symbolic_name(adapter->scsi_host),
885			gspn_rsp->gspn.fp_name, FC_SYMBOLIC_NAME_SIZE);
886
887	return 0;
888}
889
890static void zfcp_fc_rspn(struct zfcp_adapter *adapter,
891			 struct zfcp_fc_req *fc_req)
892{
893	DECLARE_COMPLETION_ONSTACK(completion);
894	struct Scsi_Host *shost = adapter->scsi_host;
895	struct zfcp_fsf_ct_els *ct_els = &fc_req->ct_els;
896	struct zfcp_fc_rspn_req *rspn_req = &fc_req->u.rspn.req;
897	struct fc_ct_hdr *rspn_rsp = &fc_req->u.rspn.rsp;
898	int ret, len;
899
900	zfcp_fc_ct_ns_init(&rspn_req->ct_hdr, FC_NS_RSPN_ID,
901			   FC_SYMBOLIC_NAME_SIZE);
902	hton24(rspn_req->rspn.fr_fid.fp_fid, fc_host_port_id(shost));
903
904	BUILD_BUG_ON(sizeof(rspn_req->name) !=
905			sizeof(fc_host_symbolic_name(shost)));
906	BUILD_BUG_ON(sizeof(rspn_req->name) !=
907			type_max(typeof(rspn_req->rspn.fr_name_len)) + 1);
908	len = strscpy(rspn_req->name, fc_host_symbolic_name(shost),
909		      sizeof(rspn_req->name));
910	/*
911	 * It should be impossible for this to truncate (see BUILD_BUG_ON()
912	 * above), but be robust anyway.
913	 */
914	if (WARN_ON(len < 0))
915		len = sizeof(rspn_req->name) - 1;
916	rspn_req->rspn.fr_name_len = len;
917
918	sg_init_one(&fc_req->sg_req, rspn_req, sizeof(*rspn_req));
919	sg_init_one(&fc_req->sg_rsp, rspn_rsp, sizeof(*rspn_rsp));
920
921	ct_els->handler = zfcp_fc_complete;
922	ct_els->handler_data = &completion;
923	ct_els->req = &fc_req->sg_req;
924	ct_els->resp = &fc_req->sg_rsp;
925
926	ret = zfcp_fsf_send_ct(&adapter->gs->ds, ct_els, NULL,
927			       ZFCP_FC_CTELS_TMO);
928	if (!ret)
929		wait_for_completion(&completion);
930}
931
932/**
933 * zfcp_fc_sym_name_update - Retrieve and update the symbolic port name
934 * @work: ns_up_work of the adapter where to update the symbolic port name
935 *
936 * Retrieve the current symbolic port name that may have been set by
937 * the hardware using the GSPN request and update the fc_host
938 * symbolic_name sysfs attribute. When running in NPIV mode (and hence
939 * the port name is unique for this system), update the symbolic port
940 * name to add Linux specific information and update the FC nameserver
941 * using the RSPN request.
942 */
943void zfcp_fc_sym_name_update(struct work_struct *work)
944{
945	struct zfcp_adapter *adapter = container_of(work, struct zfcp_adapter,
946						    ns_up_work);
947	int ret;
948	struct zfcp_fc_req *fc_req;
949
950	if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
951	    fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
952		return;
953
954	fc_req = kmem_cache_zalloc(zfcp_fc_req_cache, GFP_KERNEL);
955	if (!fc_req)
956		return;
957
958	ret = zfcp_fc_wka_port_get(&adapter->gs->ds);
959	if (ret)
960		goto out_free;
961
962	ret = zfcp_fc_gspn(adapter, fc_req);
963	if (ret || fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
964		goto out_ds_put;
965
966	memset(fc_req, 0, sizeof(*fc_req));
967	zfcp_fc_rspn(adapter, fc_req);
968
969out_ds_put:
970	zfcp_fc_wka_port_put(&adapter->gs->ds);
971out_free:
972	kmem_cache_free(zfcp_fc_req_cache, fc_req);
973}
974
975static void zfcp_fc_ct_els_job_handler(void *data)
976{
977	struct bsg_job *job = data;
978	struct zfcp_fsf_ct_els *zfcp_ct_els = job->dd_data;
979	struct fc_bsg_reply *jr = job->reply;
980
981	jr->reply_payload_rcv_len = job->reply_payload.payload_len;
982	jr->reply_data.ctels_reply.status = FC_CTELS_STATUS_OK;
983	jr->result = zfcp_ct_els->status ? -EIO : 0;
984	bsg_job_done(job, jr->result, jr->reply_payload_rcv_len);
985}
986
987static struct zfcp_fc_wka_port *zfcp_fc_job_wka_port(struct bsg_job *job)
988{
989	u32 preamble_word1;
990	u8 gs_type;
991	struct zfcp_adapter *adapter;
992	struct fc_bsg_request *bsg_request = job->request;
993	struct fc_rport *rport = fc_bsg_to_rport(job);
994	struct Scsi_Host *shost;
995
996	preamble_word1 = bsg_request->rqst_data.r_ct.preamble_word1;
997	gs_type = (preamble_word1 & 0xff000000) >> 24;
998
999	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1000	adapter = (struct zfcp_adapter *) shost->hostdata[0];
1001
1002	switch (gs_type) {
1003	case FC_FST_ALIAS:
1004		return &adapter->gs->as;
1005	case FC_FST_MGMT:
1006		return &adapter->gs->ms;
1007	case FC_FST_TIME:
1008		return &adapter->gs->ts;
1009		break;
1010	case FC_FST_DIR:
1011		return &adapter->gs->ds;
1012		break;
1013	default:
1014		return NULL;
1015	}
1016}
1017
1018static void zfcp_fc_ct_job_handler(void *data)
1019{
1020	struct bsg_job *job = data;
1021	struct zfcp_fc_wka_port *wka_port;
1022
1023	wka_port = zfcp_fc_job_wka_port(job);
1024	zfcp_fc_wka_port_put(wka_port);
1025
1026	zfcp_fc_ct_els_job_handler(data);
1027}
1028
1029static int zfcp_fc_exec_els_job(struct bsg_job *job,
1030				struct zfcp_adapter *adapter)
1031{
1032	struct zfcp_fsf_ct_els *els = job->dd_data;
1033	struct fc_rport *rport = fc_bsg_to_rport(job);
1034	struct fc_bsg_request *bsg_request = job->request;
1035	struct zfcp_port *port;
1036	u32 d_id;
1037
1038	if (rport) {
1039		port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
1040		if (!port)
1041			return -EINVAL;
1042
1043		d_id = port->d_id;
1044		put_device(&port->dev);
1045	} else
1046		d_id = ntoh24(bsg_request->rqst_data.h_els.port_id);
1047
1048	els->handler = zfcp_fc_ct_els_job_handler;
1049	return zfcp_fsf_send_els(adapter, d_id, els, job->timeout / HZ);
1050}
1051
1052static int zfcp_fc_exec_ct_job(struct bsg_job *job,
1053			       struct zfcp_adapter *adapter)
1054{
1055	int ret;
1056	struct zfcp_fsf_ct_els *ct = job->dd_data;
1057	struct zfcp_fc_wka_port *wka_port;
1058
1059	wka_port = zfcp_fc_job_wka_port(job);
1060	if (!wka_port)
1061		return -EINVAL;
1062
1063	ret = zfcp_fc_wka_port_get(wka_port);
1064	if (ret)
1065		return ret;
1066
1067	ct->handler = zfcp_fc_ct_job_handler;
1068	ret = zfcp_fsf_send_ct(wka_port, ct, NULL, job->timeout / HZ);
1069	if (ret)
1070		zfcp_fc_wka_port_put(wka_port);
1071
1072	return ret;
1073}
1074
1075int zfcp_fc_exec_bsg_job(struct bsg_job *job)
1076{
1077	struct Scsi_Host *shost;
1078	struct zfcp_adapter *adapter;
1079	struct zfcp_fsf_ct_els *ct_els = job->dd_data;
1080	struct fc_bsg_request *bsg_request = job->request;
1081	struct fc_rport *rport = fc_bsg_to_rport(job);
1082
1083	shost = rport ? rport_to_shost(rport) : fc_bsg_to_shost(job);
1084	adapter = (struct zfcp_adapter *)shost->hostdata[0];
1085
1086	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN))
1087		return -EINVAL;
1088
1089	ct_els->req = job->request_payload.sg_list;
1090	ct_els->resp = job->reply_payload.sg_list;
1091	ct_els->handler_data = job;
1092
1093	switch (bsg_request->msgcode) {
1094	case FC_BSG_RPT_ELS:
1095	case FC_BSG_HST_ELS_NOLOGIN:
1096		return zfcp_fc_exec_els_job(job, adapter);
1097	case FC_BSG_RPT_CT:
1098	case FC_BSG_HST_CT:
1099		return zfcp_fc_exec_ct_job(job, adapter);
1100	default:
1101		return -EINVAL;
1102	}
1103}
1104
1105int zfcp_fc_timeout_bsg_job(struct bsg_job *job)
1106{
1107	/* hardware tracks timeout, reset bsg timeout to not interfere */
1108	return -EAGAIN;
1109}
1110
1111int zfcp_fc_gs_setup(struct zfcp_adapter *adapter)
1112{
1113	struct zfcp_fc_wka_ports *wka_ports;
1114
1115	wka_ports = kzalloc(sizeof(struct zfcp_fc_wka_ports), GFP_KERNEL);
1116	if (!wka_ports)
1117		return -ENOMEM;
1118
1119	adapter->gs = wka_ports;
1120	zfcp_fc_wka_port_init(&wka_ports->ms, FC_FID_MGMT_SERV, adapter);
1121	zfcp_fc_wka_port_init(&wka_ports->ts, FC_FID_TIME_SERV, adapter);
1122	zfcp_fc_wka_port_init(&wka_ports->ds, FC_FID_DIR_SERV, adapter);
1123	zfcp_fc_wka_port_init(&wka_ports->as, FC_FID_ALIASES, adapter);
1124
1125	return 0;
1126}
1127
1128void zfcp_fc_gs_destroy(struct zfcp_adapter *adapter)
1129{
1130	kfree(adapter->gs);
1131	adapter->gs = NULL;
1132}
1133
1134