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[mv-sheeva.git] / 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, 2009
7  */
8
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12 #include "zfcp_ext.h"
13
14 enum rscn_address_format {
15         RSCN_PORT_ADDRESS       = 0x0,
16         RSCN_AREA_ADDRESS       = 0x1,
17         RSCN_DOMAIN_ADDRESS     = 0x2,
18         RSCN_FABRIC_ADDRESS     = 0x3,
19 };
20
21 static u32 rscn_range_mask[] = {
22         [RSCN_PORT_ADDRESS]             = 0xFFFFFF,
23         [RSCN_AREA_ADDRESS]             = 0xFFFF00,
24         [RSCN_DOMAIN_ADDRESS]           = 0xFF0000,
25         [RSCN_FABRIC_ADDRESS]           = 0x000000,
26 };
27
28 struct ct_iu_gpn_ft_req {
29         struct ct_hdr header;
30         u8 flags;
31         u8 domain_id_scope;
32         u8 area_id_scope;
33         u8 fc4_type;
34 } __attribute__ ((packed));
35
36 struct gpn_ft_resp_acc {
37         u8 control;
38         u8 port_id[3];
39         u8 reserved[4];
40         u64 wwpn;
41 } __attribute__ ((packed));
42
43 #define ZFCP_CT_SIZE_ONE_PAGE   (PAGE_SIZE - sizeof(struct ct_hdr))
44 #define ZFCP_GPN_FT_ENTRIES     (ZFCP_CT_SIZE_ONE_PAGE \
45                                         / sizeof(struct gpn_ft_resp_acc))
46 #define ZFCP_GPN_FT_BUFFERS 4
47 #define ZFCP_GPN_FT_MAX_SIZE (ZFCP_GPN_FT_BUFFERS * PAGE_SIZE \
48                                 - sizeof(struct ct_hdr))
49 #define ZFCP_GPN_FT_MAX_ENTRIES ZFCP_GPN_FT_BUFFERS * (ZFCP_GPN_FT_ENTRIES + 1)
50
51 struct ct_iu_gpn_ft_resp {
52         struct ct_hdr header;
53         struct gpn_ft_resp_acc accept[ZFCP_GPN_FT_ENTRIES];
54 } __attribute__ ((packed));
55
56 struct zfcp_gpn_ft {
57         struct zfcp_send_ct ct;
58         struct scatterlist sg_req;
59         struct scatterlist sg_resp[ZFCP_GPN_FT_BUFFERS];
60 };
61
62 struct zfcp_fc_ns_handler_data {
63         struct completion done;
64         void (*handler)(unsigned long);
65         unsigned long handler_data;
66 };
67
68 static int zfcp_wka_port_get(struct zfcp_wka_port *wka_port)
69 {
70         if (mutex_lock_interruptible(&wka_port->mutex))
71                 return -ERESTARTSYS;
72
73         if (wka_port->status == ZFCP_WKA_PORT_OFFLINE ||
74             wka_port->status == ZFCP_WKA_PORT_CLOSING) {
75                 wka_port->status = ZFCP_WKA_PORT_OPENING;
76                 if (zfcp_fsf_open_wka_port(wka_port))
77                         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
78         }
79
80         mutex_unlock(&wka_port->mutex);
81
82         wait_event_timeout(
83                 wka_port->completion_wq,
84                 wka_port->status == ZFCP_WKA_PORT_ONLINE ||
85                 wka_port->status == ZFCP_WKA_PORT_OFFLINE,
86                 HZ >> 1);
87
88         if (wka_port->status == ZFCP_WKA_PORT_ONLINE) {
89                 atomic_inc(&wka_port->refcount);
90                 return 0;
91         }
92         return -EIO;
93 }
94
95 static void zfcp_wka_port_offline(struct work_struct *work)
96 {
97         struct delayed_work *dw = to_delayed_work(work);
98         struct zfcp_wka_port *wka_port =
99                         container_of(dw, struct zfcp_wka_port, work);
100
101         /* Don't wait forvever. If the wka_port is too busy take it offline
102            through a new call later */
103         if (!wait_event_timeout(wka_port->completion_wq,
104                                 atomic_read(&wka_port->refcount) == 0,
105                                 HZ >> 1))
106                 return;
107
108         mutex_lock(&wka_port->mutex);
109         if ((atomic_read(&wka_port->refcount) != 0) ||
110             (wka_port->status != ZFCP_WKA_PORT_ONLINE))
111                 goto out;
112
113         wka_port->status = ZFCP_WKA_PORT_CLOSING;
114         if (zfcp_fsf_close_wka_port(wka_port)) {
115                 wka_port->status = ZFCP_WKA_PORT_OFFLINE;
116                 wake_up(&wka_port->completion_wq);
117         }
118 out:
119         mutex_unlock(&wka_port->mutex);
120 }
121
122 static void zfcp_wka_port_put(struct zfcp_wka_port *wka_port)
123 {
124         if (atomic_dec_return(&wka_port->refcount) != 0)
125                 return;
126         /* wait 10 miliseconds, other reqs might pop in */
127         schedule_delayed_work(&wka_port->work, HZ / 100);
128 }
129
130 void zfcp_fc_nameserver_init(struct zfcp_adapter *adapter)
131 {
132         struct zfcp_wka_port *wka_port = &adapter->nsp;
133
134         init_waitqueue_head(&wka_port->completion_wq);
135
136         wka_port->adapter = adapter;
137         wka_port->d_id = ZFCP_DID_DIRECTORY_SERVICE;
138
139         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
140         atomic_set(&wka_port->refcount, 0);
141         mutex_init(&wka_port->mutex);
142         INIT_DELAYED_WORK(&wka_port->work, zfcp_wka_port_offline);
143 }
144
145 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
146                                    struct fcp_rscn_element *elem)
147 {
148         unsigned long flags;
149         struct zfcp_port *port;
150
151         read_lock_irqsave(&zfcp_data.config_lock, flags);
152         list_for_each_entry(port, &fsf_req->adapter->port_list_head, list)
153                 if ((port->d_id & range) == (elem->nport_did & range))
154                         zfcp_test_link(port);
155
156         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
157 }
158
159 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
160 {
161         struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
162         struct fcp_rscn_head *fcp_rscn_head;
163         struct fcp_rscn_element *fcp_rscn_element;
164         u16 i;
165         u16 no_entries;
166         u32 range_mask;
167
168         fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload.data;
169         fcp_rscn_element = (struct fcp_rscn_element *) fcp_rscn_head;
170
171         /* see FC-FS */
172         no_entries = fcp_rscn_head->payload_len /
173                         sizeof(struct fcp_rscn_element);
174
175         for (i = 1; i < no_entries; i++) {
176                 /* skip head and start with 1st element */
177                 fcp_rscn_element++;
178                 range_mask = rscn_range_mask[fcp_rscn_element->addr_format];
179                 _zfcp_fc_incoming_rscn(fsf_req, range_mask, fcp_rscn_element);
180         }
181         schedule_work(&fsf_req->adapter->scan_work);
182 }
183
184 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
185 {
186         struct zfcp_adapter *adapter = req->adapter;
187         struct zfcp_port *port;
188         unsigned long flags;
189
190         read_lock_irqsave(&zfcp_data.config_lock, flags);
191         list_for_each_entry(port, &adapter->port_list_head, list)
192                 if (port->wwpn == wwpn)
193                         break;
194         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
195
196         if (port && (port->wwpn == wwpn))
197                 zfcp_erp_port_forced_reopen(port, 0, "fciwwp1", req);
198 }
199
200 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
201 {
202         struct fsf_status_read_buffer *status_buffer =
203                 (struct fsf_status_read_buffer *)req->data;
204         struct fsf_plogi *els_plogi =
205                 (struct fsf_plogi *) status_buffer->payload.data;
206
207         zfcp_fc_incoming_wwpn(req, els_plogi->serv_param.wwpn);
208 }
209
210 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
211 {
212         struct fsf_status_read_buffer *status_buffer =
213                 (struct fsf_status_read_buffer *)req->data;
214         struct fcp_logo *els_logo =
215                 (struct fcp_logo *) status_buffer->payload.data;
216
217         zfcp_fc_incoming_wwpn(req, els_logo->nport_wwpn);
218 }
219
220 /**
221  * zfcp_fc_incoming_els - handle incoming ELS
222  * @fsf_req - request which contains incoming ELS
223  */
224 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
225 {
226         struct fsf_status_read_buffer *status_buffer =
227                 (struct fsf_status_read_buffer *) fsf_req->data;
228         unsigned int els_type = status_buffer->payload.data[0];
229
230         zfcp_san_dbf_event_incoming_els(fsf_req);
231         if (els_type == LS_PLOGI)
232                 zfcp_fc_incoming_plogi(fsf_req);
233         else if (els_type == LS_LOGO)
234                 zfcp_fc_incoming_logo(fsf_req);
235         else if (els_type == LS_RSCN)
236                 zfcp_fc_incoming_rscn(fsf_req);
237 }
238
239 static void zfcp_fc_ns_handler(unsigned long data)
240 {
241         struct zfcp_fc_ns_handler_data *compl_rec =
242                         (struct zfcp_fc_ns_handler_data *) data;
243
244         if (compl_rec->handler)
245                 compl_rec->handler(compl_rec->handler_data);
246
247         complete(&compl_rec->done);
248 }
249
250 static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
251 {
252         struct zfcp_gid_pn_data *gid_pn = (struct zfcp_gid_pn_data *) data;
253         struct zfcp_send_ct *ct = &gid_pn->ct;
254         struct ct_iu_gid_pn_req *ct_iu_req = sg_virt(ct->req);
255         struct ct_iu_gid_pn_resp *ct_iu_resp = sg_virt(ct->resp);
256         struct zfcp_port *port = gid_pn->port;
257
258         if (ct->status)
259                 return;
260         if (ct_iu_resp->header.cmd_rsp_code != ZFCP_CT_ACCEPT)
261                 return;
262
263         /* paranoia */
264         if (ct_iu_req->wwpn != port->wwpn)
265                 return;
266         /* looks like a valid d_id */
267         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
268 }
269
270 int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
271                                      struct zfcp_gid_pn_data *gid_pn)
272 {
273         struct zfcp_adapter *adapter = erp_action->adapter;
274         struct zfcp_fc_ns_handler_data compl_rec;
275         int ret;
276
277         /* setup parameters for send generic command */
278         gid_pn->port = erp_action->port;
279         gid_pn->ct.wka_port = &adapter->nsp;
280         gid_pn->ct.handler = zfcp_fc_ns_handler;
281         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
282         gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
283         gid_pn->ct.req = &gid_pn->req;
284         gid_pn->ct.resp = &gid_pn->resp;
285         sg_init_one(&gid_pn->req, &gid_pn->ct_iu_req,
286                     sizeof(struct ct_iu_gid_pn_req));
287         sg_init_one(&gid_pn->resp, &gid_pn->ct_iu_resp,
288                     sizeof(struct ct_iu_gid_pn_resp));
289
290         /* setup nameserver request */
291         gid_pn->ct_iu_req.header.revision = ZFCP_CT_REVISION;
292         gid_pn->ct_iu_req.header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
293         gid_pn->ct_iu_req.header.gs_subtype = ZFCP_CT_NAME_SERVER;
294         gid_pn->ct_iu_req.header.options = ZFCP_CT_SYNCHRONOUS;
295         gid_pn->ct_iu_req.header.cmd_rsp_code = ZFCP_CT_GID_PN;
296         gid_pn->ct_iu_req.header.max_res_size = ZFCP_CT_SIZE_ONE_PAGE / 4;
297         gid_pn->ct_iu_req.wwpn = erp_action->port->wwpn;
298
299         init_completion(&compl_rec.done);
300         compl_rec.handler = zfcp_fc_ns_gid_pn_eval;
301         compl_rec.handler_data = (unsigned long) gid_pn;
302         ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.fsf_req_erp,
303                                erp_action);
304         if (!ret)
305                 wait_for_completion(&compl_rec.done);
306         return ret;
307 }
308
309 /**
310  * zfcp_fc_ns_gid_pn_request - initiate GID_PN nameserver request
311  * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
312  * return: -ENOMEM on error, 0 otherwise
313  */
314 int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
315 {
316         int ret;
317         struct zfcp_gid_pn_data *gid_pn;
318         struct zfcp_adapter *adapter = erp_action->adapter;
319
320         gid_pn = mempool_alloc(adapter->pool.data_gid_pn, GFP_ATOMIC);
321         if (!gid_pn)
322                 return -ENOMEM;
323
324         memset(gid_pn, 0, sizeof(*gid_pn));
325
326         ret = zfcp_wka_port_get(&adapter->nsp);
327         if (ret)
328                 goto out;
329
330         ret = zfcp_fc_ns_gid_pn_request(erp_action, gid_pn);
331
332         zfcp_wka_port_put(&adapter->nsp);
333 out:
334         mempool_free(gid_pn, adapter->pool.data_gid_pn);
335         return ret;
336 }
337
338 /**
339  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
340  * @port: zfcp_port structure
341  * @plogi: plogi payload
342  *
343  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
344  */
345 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fsf_plogi *plogi)
346 {
347         port->maxframe_size = plogi->serv_param.common_serv_param[7] |
348                 ((plogi->serv_param.common_serv_param[6] & 0x0F) << 8);
349         if (plogi->serv_param.class1_serv_param[0] & 0x80)
350                 port->supported_classes |= FC_COS_CLASS1;
351         if (plogi->serv_param.class2_serv_param[0] & 0x80)
352                 port->supported_classes |= FC_COS_CLASS2;
353         if (plogi->serv_param.class3_serv_param[0] & 0x80)
354                 port->supported_classes |= FC_COS_CLASS3;
355         if (plogi->serv_param.class4_serv_param[0] & 0x80)
356                 port->supported_classes |= FC_COS_CLASS4;
357 }
358
359 struct zfcp_els_adisc {
360         struct zfcp_send_els els;
361         struct scatterlist req;
362         struct scatterlist resp;
363         struct zfcp_ls_adisc ls_adisc;
364         struct zfcp_ls_adisc ls_adisc_acc;
365 };
366
367 static void zfcp_fc_adisc_handler(unsigned long data)
368 {
369         struct zfcp_els_adisc *adisc = (struct zfcp_els_adisc *) data;
370         struct zfcp_port *port = adisc->els.port;
371         struct zfcp_ls_adisc *ls_adisc = &adisc->ls_adisc_acc;
372
373         if (adisc->els.status) {
374                 /* request rejected or timed out */
375                 zfcp_erp_port_forced_reopen(port, 0, "fcadh_1", NULL);
376                 goto out;
377         }
378
379         if (!port->wwnn)
380                 port->wwnn = ls_adisc->wwnn;
381
382         if ((port->wwpn != ls_adisc->wwpn) ||
383             !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
384                 zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
385                                      "fcadh_2", NULL);
386                 goto out;
387         }
388
389         /* port is good, unblock rport without going through erp */
390         zfcp_scsi_schedule_rport_register(port);
391  out:
392         zfcp_port_put(port);
393         kfree(adisc);
394 }
395
396 static int zfcp_fc_adisc(struct zfcp_port *port)
397 {
398         struct zfcp_els_adisc *adisc;
399         struct zfcp_adapter *adapter = port->adapter;
400
401         adisc = kzalloc(sizeof(struct zfcp_els_adisc), GFP_ATOMIC);
402         if (!adisc)
403                 return -ENOMEM;
404
405         adisc->els.req = &adisc->req;
406         adisc->els.resp = &adisc->resp;
407         sg_init_one(adisc->els.req, &adisc->ls_adisc,
408                     sizeof(struct zfcp_ls_adisc));
409         sg_init_one(adisc->els.resp, &adisc->ls_adisc_acc,
410                     sizeof(struct zfcp_ls_adisc));
411
412         adisc->els.adapter = adapter;
413         adisc->els.port = port;
414         adisc->els.d_id = port->d_id;
415         adisc->els.handler = zfcp_fc_adisc_handler;
416         adisc->els.handler_data = (unsigned long) adisc;
417         adisc->els.ls_code = adisc->ls_adisc.code = ZFCP_LS_ADISC;
418
419         /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
420            without FC-AL-2 capability, so we don't set it */
421         adisc->ls_adisc.wwpn = fc_host_port_name(adapter->scsi_host);
422         adisc->ls_adisc.wwnn = fc_host_node_name(adapter->scsi_host);
423         adisc->ls_adisc.nport_id = fc_host_port_id(adapter->scsi_host);
424
425         return zfcp_fsf_send_els(&adisc->els);
426 }
427
428 void zfcp_fc_link_test_work(struct work_struct *work)
429 {
430         struct zfcp_port *port =
431                 container_of(work, struct zfcp_port, test_link_work);
432         int retval;
433
434         if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_UNBLOCKED)) {
435                 zfcp_port_put(port);
436                 return; /* port erp is running and will update rport status */
437         }
438
439         zfcp_port_get(port);
440         port->rport_task = RPORT_DEL;
441         zfcp_scsi_rport_work(&port->rport_work);
442
443         retval = zfcp_fc_adisc(port);
444         if (retval == 0)
445                 return;
446
447         /* send of ADISC was not possible */
448         zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
449
450         zfcp_port_put(port);
451 }
452
453 /**
454  * zfcp_test_link - lightweight link test procedure
455  * @port: port to be tested
456  *
457  * Test status of a link to a remote port using the ELS command ADISC.
458  * If there is a problem with the remote port, error recovery steps
459  * will be triggered.
460  */
461 void zfcp_test_link(struct zfcp_port *port)
462 {
463         zfcp_port_get(port);
464         if (!queue_work(zfcp_data.work_queue, &port->test_link_work))
465                 zfcp_port_put(port);
466 }
467
468 static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft, int buf_num)
469 {
470         struct scatterlist *sg = &gpn_ft->sg_req;
471
472         kfree(sg_virt(sg)); /* free request buffer */
473         zfcp_sg_free_table(gpn_ft->sg_resp, buf_num);
474
475         kfree(gpn_ft);
476 }
477
478 static struct zfcp_gpn_ft *zfcp_alloc_sg_env(int buf_num)
479 {
480         struct zfcp_gpn_ft *gpn_ft;
481         struct ct_iu_gpn_ft_req *req;
482
483         gpn_ft = kzalloc(sizeof(*gpn_ft), GFP_KERNEL);
484         if (!gpn_ft)
485                 return NULL;
486
487         req = kzalloc(sizeof(struct ct_iu_gpn_ft_req), GFP_KERNEL);
488         if (!req) {
489                 kfree(gpn_ft);
490                 gpn_ft = NULL;
491                 goto out;
492         }
493         sg_init_one(&gpn_ft->sg_req, req, sizeof(*req));
494
495         if (zfcp_sg_setup_table(gpn_ft->sg_resp, buf_num)) {
496                 zfcp_free_sg_env(gpn_ft, buf_num);
497                 gpn_ft = NULL;
498         }
499 out:
500         return gpn_ft;
501 }
502
503
504 static int zfcp_scan_issue_gpn_ft(struct zfcp_gpn_ft *gpn_ft,
505                                   struct zfcp_adapter *adapter,
506                                   int max_bytes)
507 {
508         struct zfcp_send_ct *ct = &gpn_ft->ct;
509         struct ct_iu_gpn_ft_req *req = sg_virt(&gpn_ft->sg_req);
510         struct zfcp_fc_ns_handler_data compl_rec;
511         int ret;
512
513         /* prepare CT IU for GPN_FT */
514         req->header.revision = ZFCP_CT_REVISION;
515         req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
516         req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
517         req->header.options = ZFCP_CT_SYNCHRONOUS;
518         req->header.cmd_rsp_code = ZFCP_CT_GPN_FT;
519         req->header.max_res_size = max_bytes / 4;
520         req->flags = 0;
521         req->domain_id_scope = 0;
522         req->area_id_scope = 0;
523         req->fc4_type = ZFCP_CT_SCSI_FCP;
524
525         /* prepare zfcp_send_ct */
526         ct->wka_port = &adapter->nsp;
527         ct->handler = zfcp_fc_ns_handler;
528         ct->handler_data = (unsigned long)&compl_rec;
529         ct->timeout = 10;
530         ct->req = &gpn_ft->sg_req;
531         ct->resp = gpn_ft->sg_resp;
532
533         init_completion(&compl_rec.done);
534         compl_rec.handler = NULL;
535         ret = zfcp_fsf_send_ct(ct, NULL, NULL);
536         if (!ret)
537                 wait_for_completion(&compl_rec.done);
538         return ret;
539 }
540
541 static void zfcp_validate_port(struct zfcp_port *port)
542 {
543         struct zfcp_adapter *adapter = port->adapter;
544
545         atomic_clear_mask(ZFCP_STATUS_COMMON_NOESC, &port->status);
546
547         if ((port->supported_classes != 0) ||
548             !list_empty(&port->unit_list_head)) {
549                 zfcp_port_put(port);
550                 return;
551         }
552         zfcp_erp_port_shutdown(port, 0, "fcpval1", NULL);
553         zfcp_erp_wait(adapter);
554         zfcp_port_put(port);
555         zfcp_port_dequeue(port);
556 }
557
558 static int zfcp_scan_eval_gpn_ft(struct zfcp_gpn_ft *gpn_ft, int max_entries)
559 {
560         struct zfcp_send_ct *ct = &gpn_ft->ct;
561         struct scatterlist *sg = gpn_ft->sg_resp;
562         struct ct_hdr *hdr = sg_virt(sg);
563         struct gpn_ft_resp_acc *acc = sg_virt(sg);
564         struct zfcp_adapter *adapter = ct->wka_port->adapter;
565         struct zfcp_port *port, *tmp;
566         u32 d_id;
567         int ret = 0, x, last = 0;
568
569         if (ct->status)
570                 return -EIO;
571
572         if (hdr->cmd_rsp_code != ZFCP_CT_ACCEPT) {
573                 if (hdr->reason_code == ZFCP_CT_UNABLE_TO_PERFORM_CMD)
574                         return -EAGAIN; /* might be a temporary condition */
575                 return -EIO;
576         }
577
578         if (hdr->max_res_size) {
579                 dev_warn(&adapter->ccw_device->dev,
580                          "The name server reported %d words residual data\n",
581                          hdr->max_res_size);
582                 return -E2BIG;
583         }
584
585         down(&zfcp_data.config_sema);
586
587         /* first entry is the header */
588         for (x = 1; x < max_entries && !last; x++) {
589                 if (x % (ZFCP_GPN_FT_ENTRIES + 1))
590                         acc++;
591                 else
592                         acc = sg_virt(++sg);
593
594                 last = acc->control & 0x80;
595                 d_id = acc->port_id[0] << 16 | acc->port_id[1] << 8 |
596                        acc->port_id[2];
597
598                 /* don't attach ports with a well known address */
599                 if ((d_id & ZFCP_DID_WKA) == ZFCP_DID_WKA)
600                         continue;
601                 /* skip the adapter's port and known remote ports */
602                 if (acc->wwpn == fc_host_port_name(adapter->scsi_host))
603                         continue;
604                 port = zfcp_get_port_by_wwpn(adapter, acc->wwpn);
605                 if (port) {
606                         zfcp_port_get(port);
607                         continue;
608                 }
609
610                 port = zfcp_port_enqueue(adapter, acc->wwpn,
611                                          ZFCP_STATUS_COMMON_NOESC, d_id);
612                 if (IS_ERR(port))
613                         ret = PTR_ERR(port);
614                 else
615                         zfcp_erp_port_reopen(port, 0, "fcegpf1", NULL);
616         }
617
618         zfcp_erp_wait(adapter);
619         list_for_each_entry_safe(port, tmp, &adapter->port_list_head, list)
620                 zfcp_validate_port(port);
621         up(&zfcp_data.config_sema);
622         return ret;
623 }
624
625 /**
626  * zfcp_scan_ports - scan remote ports and attach new ports
627  * @adapter: pointer to struct zfcp_adapter
628  */
629 int zfcp_scan_ports(struct zfcp_adapter *adapter)
630 {
631         int ret, i;
632         struct zfcp_gpn_ft *gpn_ft;
633         int chain, max_entries, buf_num, max_bytes;
634
635         chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
636         buf_num = chain ? ZFCP_GPN_FT_BUFFERS : 1;
637         max_entries = chain ? ZFCP_GPN_FT_MAX_ENTRIES : ZFCP_GPN_FT_ENTRIES;
638         max_bytes = chain ? ZFCP_GPN_FT_MAX_SIZE : ZFCP_CT_SIZE_ONE_PAGE;
639
640         if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT)
641                 return 0;
642
643         ret = zfcp_wka_port_get(&adapter->nsp);
644         if (ret)
645                 return ret;
646
647         gpn_ft = zfcp_alloc_sg_env(buf_num);
648         if (!gpn_ft) {
649                 ret = -ENOMEM;
650                 goto out;
651         }
652
653         for (i = 0; i < 3; i++) {
654                 ret = zfcp_scan_issue_gpn_ft(gpn_ft, adapter, max_bytes);
655                 if (!ret) {
656                         ret = zfcp_scan_eval_gpn_ft(gpn_ft, max_entries);
657                         if (ret == -EAGAIN)
658                                 ssleep(1);
659                         else
660                                 break;
661                 }
662         }
663         zfcp_free_sg_env(gpn_ft, buf_num);
664 out:
665         zfcp_wka_port_put(&adapter->nsp);
666         return ret;
667 }
668
669
670 void _zfcp_scan_ports_later(struct work_struct *work)
671 {
672         zfcp_scan_ports(container_of(work, struct zfcp_adapter, scan_work));
673 }