[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP
[safe/jmp/linux-2.6] / drivers / s390 / scsi / zfcp_fc.c
1 /*
2  * zfcp device driver
3  *
4  * Fibre Channel related functions for the zfcp device driver.
5  *
6  * Copyright IBM Corporation 2008
7  */
8
9 #include "zfcp_ext.h"
10
11 struct ct_iu_gpn_ft_req {
12         struct ct_hdr header;
13         u8 flags;
14         u8 domain_id_scope;
15         u8 area_id_scope;
16         u8 fc4_type;
17 } __attribute__ ((packed));
18
19 struct gpn_ft_resp_acc {
20         u8 control;
21         u8 port_id[3];
22         u8 reserved[4];
23         u64 wwpn;
24 } __attribute__ ((packed));
25
26 #define ZFCP_GPN_FT_ENTRIES ((PAGE_SIZE - sizeof(struct ct_hdr)) \
27                                 / sizeof(struct gpn_ft_resp_acc))
28 #define ZFCP_GPN_FT_BUFFERS 4
29 #define ZFCP_GPN_FT_MAX_ENTRIES ZFCP_GPN_FT_BUFFERS * (ZFCP_GPN_FT_ENTRIES + 1)
30
31 struct ct_iu_gpn_ft_resp {
32         struct ct_hdr header;
33         struct gpn_ft_resp_acc accept[ZFCP_GPN_FT_ENTRIES];
34 } __attribute__ ((packed));
35
36 struct zfcp_gpn_ft {
37         struct zfcp_send_ct ct;
38         struct scatterlist sg_req;
39         struct scatterlist sg_resp[ZFCP_GPN_FT_BUFFERS];
40 };
41
42 struct zfcp_fc_ns_handler_data {
43         struct completion done;
44         void (*handler)(unsigned long);
45         unsigned long handler_data;
46 };
47
48 static int zfcp_wka_port_get(struct zfcp_wka_port *wka_port)
49 {
50         if (mutex_lock_interruptible(&wka_port->mutex))
51                 return -ERESTARTSYS;
52
53         if (wka_port->status == ZFCP_WKA_PORT_OFFLINE ||
54             wka_port->status == ZFCP_WKA_PORT_CLOSING) {
55                 wka_port->status = ZFCP_WKA_PORT_OPENING;
56                 if (zfcp_fsf_open_wka_port(wka_port))
57                         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
58         }
59
60         mutex_unlock(&wka_port->mutex);
61
62         wait_event_timeout(
63                 wka_port->completion_wq,
64                 wka_port->status == ZFCP_WKA_PORT_ONLINE ||
65                 wka_port->status == ZFCP_WKA_PORT_OFFLINE,
66                 HZ >> 1);
67
68         if (wka_port->status == ZFCP_WKA_PORT_ONLINE) {
69                 atomic_inc(&wka_port->refcount);
70                 return 0;
71         }
72         return -EIO;
73 }
74
75 static void zfcp_wka_port_offline(struct work_struct *work)
76 {
77         struct delayed_work *dw = container_of(work, struct delayed_work, work);
78         struct zfcp_wka_port *wka_port =
79                         container_of(dw, struct zfcp_wka_port, work);
80
81         wait_event(wka_port->completion_wq,
82                         atomic_read(&wka_port->refcount) == 0);
83
84         mutex_lock(&wka_port->mutex);
85         if ((atomic_read(&wka_port->refcount) != 0) ||
86             (wka_port->status != ZFCP_WKA_PORT_ONLINE))
87                 goto out;
88
89         wka_port->status = ZFCP_WKA_PORT_CLOSING;
90         if (zfcp_fsf_close_wka_port(wka_port)) {
91                 wka_port->status = ZFCP_WKA_PORT_OFFLINE;
92                 wake_up(&wka_port->completion_wq);
93         }
94 out:
95         mutex_unlock(&wka_port->mutex);
96 }
97
98 static void zfcp_wka_port_put(struct zfcp_wka_port *wka_port)
99 {
100         if (atomic_dec_return(&wka_port->refcount) != 0)
101                 return;
102         /* wait 10 miliseconds, other reqs might pop in */
103         schedule_delayed_work(&wka_port->work, HZ / 100);
104 }
105
106 void zfcp_fc_nameserver_init(struct zfcp_adapter *adapter)
107 {
108         struct zfcp_wka_port *wka_port = &adapter->nsp;
109
110         init_waitqueue_head(&wka_port->completion_wq);
111
112         wka_port->adapter = adapter;
113         wka_port->d_id = ZFCP_DID_DIRECTORY_SERVICE;
114
115         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
116         atomic_set(&wka_port->refcount, 0);
117         mutex_init(&wka_port->mutex);
118         INIT_DELAYED_WORK(&wka_port->work, zfcp_wka_port_offline);
119 }
120
121 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
122                                    struct fcp_rscn_element *elem)
123 {
124         unsigned long flags;
125         struct zfcp_port *port;
126
127         read_lock_irqsave(&zfcp_data.config_lock, flags);
128         list_for_each_entry(port, &fsf_req->adapter->port_list_head, list) {
129                 if (!(atomic_read(&port->status) & ZFCP_STATUS_PORT_PHYS_OPEN))
130                         /* Try to connect to unused ports anyway. */
131                         zfcp_erp_port_reopen(port,
132                                              ZFCP_STATUS_COMMON_ERP_FAILED,
133                                              82, fsf_req);
134                 else if ((port->d_id & range) == (elem->nport_did & range))
135                         /* Check connection status for connected ports */
136                         zfcp_test_link(port);
137         }
138         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
139 }
140
141 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
142 {
143         struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
144         struct fcp_rscn_head *fcp_rscn_head;
145         struct fcp_rscn_element *fcp_rscn_element;
146         u16 i;
147         u16 no_entries;
148         u32 range_mask;
149
150         fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload.data;
151         fcp_rscn_element = (struct fcp_rscn_element *) fcp_rscn_head;
152
153         /* see FC-FS */
154         no_entries = fcp_rscn_head->payload_len /
155                         sizeof(struct fcp_rscn_element);
156
157         for (i = 1; i < no_entries; i++) {
158                 /* skip head and start with 1st element */
159                 fcp_rscn_element++;
160                 switch (fcp_rscn_element->addr_format) {
161                 case ZFCP_PORT_ADDRESS:
162                         range_mask = ZFCP_PORTS_RANGE_PORT;
163                         break;
164                 case ZFCP_AREA_ADDRESS:
165                         range_mask = ZFCP_PORTS_RANGE_AREA;
166                         break;
167                 case ZFCP_DOMAIN_ADDRESS:
168                         range_mask = ZFCP_PORTS_RANGE_DOMAIN;
169                         break;
170                 case ZFCP_FABRIC_ADDRESS:
171                         range_mask = ZFCP_PORTS_RANGE_FABRIC;
172                         break;
173                 default:
174                         continue;
175                 }
176                 _zfcp_fc_incoming_rscn(fsf_req, range_mask, fcp_rscn_element);
177         }
178         schedule_work(&fsf_req->adapter->scan_work);
179 }
180
181 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
182 {
183         struct zfcp_adapter *adapter = req->adapter;
184         struct zfcp_port *port;
185         unsigned long flags;
186
187         read_lock_irqsave(&zfcp_data.config_lock, flags);
188         list_for_each_entry(port, &adapter->port_list_head, list)
189                 if (port->wwpn == wwpn)
190                         break;
191         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
192
193         if (port && (port->wwpn == wwpn))
194                 zfcp_erp_port_forced_reopen(port, 0, 83, req);
195 }
196
197 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
198 {
199         struct fsf_status_read_buffer *status_buffer =
200                 (struct fsf_status_read_buffer *)req->data;
201         struct fsf_plogi *els_plogi =
202                 (struct fsf_plogi *) status_buffer->payload.data;
203
204         zfcp_fc_incoming_wwpn(req, els_plogi->serv_param.wwpn);
205 }
206
207 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
208 {
209         struct fsf_status_read_buffer *status_buffer =
210                 (struct fsf_status_read_buffer *)req->data;
211         struct fcp_logo *els_logo =
212                 (struct fcp_logo *) status_buffer->payload.data;
213
214         zfcp_fc_incoming_wwpn(req, els_logo->nport_wwpn);
215 }
216
217 /**
218  * zfcp_fc_incoming_els - handle incoming ELS
219  * @fsf_req - request which contains incoming ELS
220  */
221 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
222 {
223         struct fsf_status_read_buffer *status_buffer =
224                 (struct fsf_status_read_buffer *) fsf_req->data;
225         unsigned int els_type = status_buffer->payload.data[0];
226
227         zfcp_san_dbf_event_incoming_els(fsf_req);
228         if (els_type == LS_PLOGI)
229                 zfcp_fc_incoming_plogi(fsf_req);
230         else if (els_type == LS_LOGO)
231                 zfcp_fc_incoming_logo(fsf_req);
232         else if (els_type == LS_RSCN)
233                 zfcp_fc_incoming_rscn(fsf_req);
234 }
235
236 static void zfcp_fc_ns_handler(unsigned long data)
237 {
238         struct zfcp_fc_ns_handler_data *compl_rec =
239                         (struct zfcp_fc_ns_handler_data *) data;
240
241         if (compl_rec->handler)
242                 compl_rec->handler(compl_rec->handler_data);
243
244         complete(&compl_rec->done);
245 }
246
247 static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
248 {
249         struct zfcp_gid_pn_data *gid_pn = (struct zfcp_gid_pn_data *) data;
250         struct zfcp_send_ct *ct = &gid_pn->ct;
251         struct ct_iu_gid_pn_req *ct_iu_req = sg_virt(ct->req);
252         struct ct_iu_gid_pn_resp *ct_iu_resp = sg_virt(ct->resp);
253         struct zfcp_port *port = gid_pn->port;
254
255         if (ct->status)
256                 return;
257         if (ct_iu_resp->header.cmd_rsp_code != ZFCP_CT_ACCEPT) {
258                 atomic_set_mask(ZFCP_STATUS_PORT_INVALID_WWPN, &port->status);
259                 return;
260         }
261         /* paranoia */
262         if (ct_iu_req->wwpn != port->wwpn)
263                 return;
264         /* looks like a valid d_id */
265         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
266         atomic_set_mask(ZFCP_STATUS_PORT_DID_DID, &port->status);
267 }
268
269 int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
270                                      struct zfcp_gid_pn_data *gid_pn)
271 {
272         struct zfcp_adapter *adapter = erp_action->adapter;
273         struct zfcp_fc_ns_handler_data compl_rec;
274         int ret;
275
276         /* setup parameters for send generic command */
277         gid_pn->port = erp_action->port;
278         gid_pn->ct.wka_port = &adapter->nsp;
279         gid_pn->ct.handler = zfcp_fc_ns_handler;
280         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
281         gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
282         gid_pn->ct.req = &gid_pn->req;
283         gid_pn->ct.resp = &gid_pn->resp;
284         gid_pn->ct.req_count = 1;
285         gid_pn->ct.resp_count = 1;
286         sg_init_one(&gid_pn->req, &gid_pn->ct_iu_req,
287                     sizeof(struct ct_iu_gid_pn_req));
288         sg_init_one(&gid_pn->resp, &gid_pn->ct_iu_resp,
289                     sizeof(struct ct_iu_gid_pn_resp));
290
291         /* setup nameserver request */
292         gid_pn->ct_iu_req.header.revision = ZFCP_CT_REVISION;
293         gid_pn->ct_iu_req.header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
294         gid_pn->ct_iu_req.header.gs_subtype = ZFCP_CT_NAME_SERVER;
295         gid_pn->ct_iu_req.header.options = ZFCP_CT_SYNCHRONOUS;
296         gid_pn->ct_iu_req.header.cmd_rsp_code = ZFCP_CT_GID_PN;
297         gid_pn->ct_iu_req.header.max_res_size = ZFCP_CT_MAX_SIZE;
298         gid_pn->ct_iu_req.wwpn = erp_action->port->wwpn;
299
300         init_completion(&compl_rec.done);
301         compl_rec.handler = zfcp_fc_ns_gid_pn_eval;
302         compl_rec.handler_data = (unsigned long) gid_pn;
303         ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.fsf_req_erp,
304                                erp_action);
305         if (!ret)
306                 wait_for_completion(&compl_rec.done);
307         return ret;
308 }
309
310 /**
311  * zfcp_fc_ns_gid_pn_request - initiate GID_PN nameserver request
312  * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
313  * return: -ENOMEM on error, 0 otherwise
314  */
315 int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
316 {
317         int ret;
318         struct zfcp_gid_pn_data *gid_pn;
319         struct zfcp_adapter *adapter = erp_action->adapter;
320
321         gid_pn = mempool_alloc(adapter->pool.data_gid_pn, GFP_ATOMIC);
322         if (!gid_pn)
323                 return -ENOMEM;
324
325         memset(gid_pn, 0, sizeof(*gid_pn));
326
327         ret = zfcp_wka_port_get(&adapter->nsp);
328         if (ret)
329                 goto out;
330
331         ret = zfcp_fc_ns_gid_pn_request(erp_action, gid_pn);
332
333         zfcp_wka_port_put(&adapter->nsp);
334 out:
335         mempool_free(gid_pn, adapter->pool.data_gid_pn);
336         return ret;
337 }
338
339 /**
340  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
341  * @port: zfcp_port structure
342  * @plogi: plogi payload
343  *
344  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
345  */
346 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fsf_plogi *plogi)
347 {
348         port->maxframe_size = plogi->serv_param.common_serv_param[7] |
349                 ((plogi->serv_param.common_serv_param[6] & 0x0F) << 8);
350         if (plogi->serv_param.class1_serv_param[0] & 0x80)
351                 port->supported_classes |= FC_COS_CLASS1;
352         if (plogi->serv_param.class2_serv_param[0] & 0x80)
353                 port->supported_classes |= FC_COS_CLASS2;
354         if (plogi->serv_param.class3_serv_param[0] & 0x80)
355                 port->supported_classes |= FC_COS_CLASS3;
356         if (plogi->serv_param.class4_serv_param[0] & 0x80)
357                 port->supported_classes |= FC_COS_CLASS4;
358 }
359
360 struct zfcp_els_adisc {
361         struct zfcp_send_els els;
362         struct scatterlist req;
363         struct scatterlist resp;
364         struct zfcp_ls_adisc ls_adisc;
365         struct zfcp_ls_adisc ls_adisc_acc;
366 };
367
368 static void zfcp_fc_adisc_handler(unsigned long data)
369 {
370         struct zfcp_els_adisc *adisc = (struct zfcp_els_adisc *) data;
371         struct zfcp_port *port = adisc->els.port;
372         struct zfcp_ls_adisc *ls_adisc = &adisc->ls_adisc_acc;
373
374         if (adisc->els.status) {
375                 /* request rejected or timed out */
376                 zfcp_erp_port_forced_reopen(port, 0, 63, NULL);
377                 goto out;
378         }
379
380         if (!port->wwnn)
381                 port->wwnn = ls_adisc->wwnn;
382
383         if (port->wwpn != ls_adisc->wwpn)
384                 zfcp_erp_port_reopen(port, 0, 64, NULL);
385
386  out:
387         zfcp_port_put(port);
388         kfree(adisc);
389 }
390
391 static int zfcp_fc_adisc(struct zfcp_port *port)
392 {
393         struct zfcp_els_adisc *adisc;
394         struct zfcp_adapter *adapter = port->adapter;
395
396         adisc = kzalloc(sizeof(struct zfcp_els_adisc), GFP_ATOMIC);
397         if (!adisc)
398                 return -ENOMEM;
399
400         adisc->els.req = &adisc->req;
401         adisc->els.resp = &adisc->resp;
402         sg_init_one(adisc->els.req, &adisc->ls_adisc,
403                     sizeof(struct zfcp_ls_adisc));
404         sg_init_one(adisc->els.resp, &adisc->ls_adisc_acc,
405                     sizeof(struct zfcp_ls_adisc));
406
407         adisc->els.req_count = 1;
408         adisc->els.resp_count = 1;
409         adisc->els.adapter = adapter;
410         adisc->els.port = port;
411         adisc->els.d_id = port->d_id;
412         adisc->els.handler = zfcp_fc_adisc_handler;
413         adisc->els.handler_data = (unsigned long) adisc;
414         adisc->els.ls_code = adisc->ls_adisc.code = ZFCP_LS_ADISC;
415
416         /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
417            without FC-AL-2 capability, so we don't set it */
418         adisc->ls_adisc.wwpn = fc_host_port_name(adapter->scsi_host);
419         adisc->ls_adisc.wwnn = fc_host_node_name(adapter->scsi_host);
420         adisc->ls_adisc.nport_id = fc_host_port_id(adapter->scsi_host);
421
422         return zfcp_fsf_send_els(&adisc->els);
423 }
424
425 /**
426  * zfcp_test_link - lightweight link test procedure
427  * @port: port to be tested
428  *
429  * Test status of a link to a remote port using the ELS command ADISC.
430  * If there is a problem with the remote port, error recovery steps
431  * will be triggered.
432  */
433 void zfcp_test_link(struct zfcp_port *port)
434 {
435         int retval;
436
437         zfcp_port_get(port);
438         retval = zfcp_fc_adisc(port);
439         if (retval == 0)
440                 return;
441
442         /* send of ADISC was not possible */
443         zfcp_port_put(port);
444         if (retval != -EBUSY)
445                 zfcp_erp_port_forced_reopen(port, 0, 65, NULL);
446 }
447
448 static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft)
449 {
450         struct scatterlist *sg = &gpn_ft->sg_req;
451
452         kfree(sg_virt(sg)); /* free request buffer */
453         zfcp_sg_free_table(gpn_ft->sg_resp, ZFCP_GPN_FT_BUFFERS);
454
455         kfree(gpn_ft);
456 }
457
458 static struct zfcp_gpn_ft *zfcp_alloc_sg_env(void)
459 {
460         struct zfcp_gpn_ft *gpn_ft;
461         struct ct_iu_gpn_ft_req *req;
462
463         gpn_ft = kzalloc(sizeof(*gpn_ft), GFP_KERNEL);
464         if (!gpn_ft)
465                 return NULL;
466
467         req = kzalloc(sizeof(struct ct_iu_gpn_ft_req), GFP_KERNEL);
468         if (!req) {
469                 kfree(gpn_ft);
470                 gpn_ft = NULL;
471                 goto out;
472         }
473         sg_init_one(&gpn_ft->sg_req, req, sizeof(*req));
474
475         if (zfcp_sg_setup_table(gpn_ft->sg_resp, ZFCP_GPN_FT_BUFFERS)) {
476                 zfcp_free_sg_env(gpn_ft);
477                 gpn_ft = NULL;
478         }
479 out:
480         return gpn_ft;
481 }
482
483
484 static int zfcp_scan_issue_gpn_ft(struct zfcp_gpn_ft *gpn_ft,
485                                   struct zfcp_adapter *adapter)
486 {
487         struct zfcp_send_ct *ct = &gpn_ft->ct;
488         struct ct_iu_gpn_ft_req *req = sg_virt(&gpn_ft->sg_req);
489         struct zfcp_fc_ns_handler_data compl_rec;
490         int ret;
491
492         /* prepare CT IU for GPN_FT */
493         req->header.revision = ZFCP_CT_REVISION;
494         req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
495         req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
496         req->header.options = ZFCP_CT_SYNCHRONOUS;
497         req->header.cmd_rsp_code = ZFCP_CT_GPN_FT;
498         req->header.max_res_size = (sizeof(struct gpn_ft_resp_acc) *
499                                         (ZFCP_GPN_FT_MAX_ENTRIES - 1)) >> 2;
500         req->flags = 0;
501         req->domain_id_scope = 0;
502         req->area_id_scope = 0;
503         req->fc4_type = ZFCP_CT_SCSI_FCP;
504
505         /* prepare zfcp_send_ct */
506         ct->wka_port = &adapter->nsp;
507         ct->handler = zfcp_fc_ns_handler;
508         ct->handler_data = (unsigned long)&compl_rec;
509         ct->timeout = 10;
510         ct->req = &gpn_ft->sg_req;
511         ct->resp = gpn_ft->sg_resp;
512         ct->req_count = 1;
513         ct->resp_count = ZFCP_GPN_FT_BUFFERS;
514
515         init_completion(&compl_rec.done);
516         compl_rec.handler = NULL;
517         ret = zfcp_fsf_send_ct(ct, NULL, NULL);
518         if (!ret)
519                 wait_for_completion(&compl_rec.done);
520         return ret;
521 }
522
523 static void zfcp_validate_port(struct zfcp_port *port)
524 {
525         struct zfcp_adapter *adapter = port->adapter;
526
527         atomic_clear_mask(ZFCP_STATUS_COMMON_NOESC, &port->status);
528
529         if ((port->supported_classes != 0) ||
530             !list_empty(&port->unit_list_head)) {
531                 zfcp_port_put(port);
532                 return;
533         }
534         zfcp_erp_port_shutdown(port, 0, 151, NULL);
535         zfcp_erp_wait(adapter);
536         zfcp_port_put(port);
537         zfcp_port_dequeue(port);
538 }
539
540 static int zfcp_scan_eval_gpn_ft(struct zfcp_gpn_ft *gpn_ft)
541 {
542         struct zfcp_send_ct *ct = &gpn_ft->ct;
543         struct scatterlist *sg = gpn_ft->sg_resp;
544         struct ct_hdr *hdr = sg_virt(sg);
545         struct gpn_ft_resp_acc *acc = sg_virt(sg);
546         struct zfcp_adapter *adapter = ct->wka_port->adapter;
547         struct zfcp_port *port, *tmp;
548         u32 d_id;
549         int ret = 0, x, last = 0;
550
551         if (ct->status)
552                 return -EIO;
553
554         if (hdr->cmd_rsp_code != ZFCP_CT_ACCEPT) {
555                 if (hdr->reason_code == ZFCP_CT_UNABLE_TO_PERFORM_CMD)
556                         return -EAGAIN; /* might be a temporary condition */
557                 return -EIO;
558         }
559
560         if (hdr->max_res_size)
561                 return -E2BIG;
562
563         down(&zfcp_data.config_sema);
564
565         /* first entry is the header */
566         for (x = 1; x < ZFCP_GPN_FT_MAX_ENTRIES && !last; x++) {
567                 if (x % (ZFCP_GPN_FT_ENTRIES + 1))
568                         acc++;
569                 else
570                         acc = sg_virt(++sg);
571
572                 last = acc->control & 0x80;
573                 d_id = acc->port_id[0] << 16 | acc->port_id[1] << 8 |
574                        acc->port_id[2];
575
576                 /* don't attach ports with a well known address */
577                 if ((d_id & ZFCP_DID_WKA) == ZFCP_DID_WKA)
578                         continue;
579                 /* skip the adapter's port and known remote ports */
580                 if (acc->wwpn == fc_host_port_name(adapter->scsi_host))
581                         continue;
582                 port = zfcp_get_port_by_wwpn(adapter, acc->wwpn);
583                 if (port) {
584                         zfcp_port_get(port);
585                         continue;
586                 }
587
588                 port = zfcp_port_enqueue(adapter, acc->wwpn,
589                                          ZFCP_STATUS_PORT_DID_DID |
590                                          ZFCP_STATUS_COMMON_NOESC, d_id);
591                 if (IS_ERR(port))
592                         ret = PTR_ERR(port);
593                 else
594                         zfcp_erp_port_reopen(port, 0, 149, NULL);
595         }
596
597         zfcp_erp_wait(adapter);
598         list_for_each_entry_safe(port, tmp, &adapter->port_list_head, list)
599                 zfcp_validate_port(port);
600         up(&zfcp_data.config_sema);
601         return ret;
602 }
603
604 /**
605  * zfcp_scan_ports - scan remote ports and attach new ports
606  * @adapter: pointer to struct zfcp_adapter
607  */
608 int zfcp_scan_ports(struct zfcp_adapter *adapter)
609 {
610         int ret, i;
611         struct zfcp_gpn_ft *gpn_ft;
612
613         if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT)
614                 return 0;
615
616         ret = zfcp_wka_port_get(&adapter->nsp);
617         if (ret)
618                 return ret;
619
620         gpn_ft = zfcp_alloc_sg_env();
621         if (!gpn_ft) {
622                 ret = -ENOMEM;
623                 goto out;
624         }
625
626         for (i = 0; i < 3; i++) {
627                 ret = zfcp_scan_issue_gpn_ft(gpn_ft, adapter);
628                 if (!ret) {
629                         ret = zfcp_scan_eval_gpn_ft(gpn_ft);
630                         if (ret == -EAGAIN)
631                                 ssleep(1);
632                         else
633                                 break;
634                 }
635         }
636         zfcp_free_sg_env(gpn_ft);
637 out:
638         zfcp_wka_port_put(&adapter->nsp);
639         return ret;
640 }
641
642
643 void _zfcp_scan_ports_later(struct work_struct *work)
644 {
645         zfcp_scan_ports(container_of(work, struct zfcp_adapter, scan_work));
646 }