Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc
[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, 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         mutex_lock(&wka_port->mutex);
102         if ((atomic_read(&wka_port->refcount) != 0) ||
103             (wka_port->status != ZFCP_WKA_PORT_ONLINE))
104                 goto out;
105
106         wka_port->status = ZFCP_WKA_PORT_CLOSING;
107         if (zfcp_fsf_close_wka_port(wka_port)) {
108                 wka_port->status = ZFCP_WKA_PORT_OFFLINE;
109                 wake_up(&wka_port->completion_wq);
110         }
111 out:
112         mutex_unlock(&wka_port->mutex);
113 }
114
115 static void zfcp_wka_port_put(struct zfcp_wka_port *wka_port)
116 {
117         if (atomic_dec_return(&wka_port->refcount) != 0)
118                 return;
119         /* wait 10 miliseconds, other reqs might pop in */
120         schedule_delayed_work(&wka_port->work, HZ / 100);
121 }
122
123 void zfcp_fc_nameserver_init(struct zfcp_adapter *adapter)
124 {
125         struct zfcp_wka_port *wka_port = &adapter->nsp;
126
127         init_waitqueue_head(&wka_port->completion_wq);
128
129         wka_port->adapter = adapter;
130         wka_port->d_id = ZFCP_DID_DIRECTORY_SERVICE;
131
132         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
133         atomic_set(&wka_port->refcount, 0);
134         mutex_init(&wka_port->mutex);
135         INIT_DELAYED_WORK(&wka_port->work, zfcp_wka_port_offline);
136 }
137
138 void zfcp_fc_wka_port_force_offline(struct zfcp_wka_port *wka)
139 {
140         cancel_delayed_work_sync(&wka->work);
141         mutex_lock(&wka->mutex);
142         wka->status = ZFCP_WKA_PORT_OFFLINE;
143         mutex_unlock(&wka->mutex);
144 }
145
146 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
147                                    struct fcp_rscn_element *elem)
148 {
149         unsigned long flags;
150         struct zfcp_port *port;
151
152         read_lock_irqsave(&zfcp_data.config_lock, flags);
153         list_for_each_entry(port, &fsf_req->adapter->port_list_head, list)
154                 if ((port->d_id & range) == (elem->nport_did & range))
155                         zfcp_test_link(port);
156
157         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
158 }
159
160 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
161 {
162         struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
163         struct fcp_rscn_head *fcp_rscn_head;
164         struct fcp_rscn_element *fcp_rscn_element;
165         u16 i;
166         u16 no_entries;
167         u32 range_mask;
168
169         fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload.data;
170         fcp_rscn_element = (struct fcp_rscn_element *) fcp_rscn_head;
171
172         /* see FC-FS */
173         no_entries = fcp_rscn_head->payload_len /
174                         sizeof(struct fcp_rscn_element);
175
176         for (i = 1; i < no_entries; i++) {
177                 /* skip head and start with 1st element */
178                 fcp_rscn_element++;
179                 range_mask = rscn_range_mask[fcp_rscn_element->addr_format];
180                 _zfcp_fc_incoming_rscn(fsf_req, range_mask, fcp_rscn_element);
181         }
182         schedule_work(&fsf_req->adapter->scan_work);
183 }
184
185 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
186 {
187         struct zfcp_adapter *adapter = req->adapter;
188         struct zfcp_port *port;
189         unsigned long flags;
190
191         read_lock_irqsave(&zfcp_data.config_lock, flags);
192         list_for_each_entry(port, &adapter->port_list_head, list)
193                 if (port->wwpn == wwpn)
194                         break;
195         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
196
197         if (port && (port->wwpn == wwpn))
198                 zfcp_erp_port_forced_reopen(port, 0, "fciwwp1", req);
199 }
200
201 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
202 {
203         struct fsf_status_read_buffer *status_buffer =
204                 (struct fsf_status_read_buffer *)req->data;
205         struct fsf_plogi *els_plogi =
206                 (struct fsf_plogi *) status_buffer->payload.data;
207
208         zfcp_fc_incoming_wwpn(req, els_plogi->serv_param.wwpn);
209 }
210
211 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
212 {
213         struct fsf_status_read_buffer *status_buffer =
214                 (struct fsf_status_read_buffer *)req->data;
215         struct fcp_logo *els_logo =
216                 (struct fcp_logo *) status_buffer->payload.data;
217
218         zfcp_fc_incoming_wwpn(req, els_logo->nport_wwpn);
219 }
220
221 /**
222  * zfcp_fc_incoming_els - handle incoming ELS
223  * @fsf_req - request which contains incoming ELS
224  */
225 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
226 {
227         struct fsf_status_read_buffer *status_buffer =
228                 (struct fsf_status_read_buffer *) fsf_req->data;
229         unsigned int els_type = status_buffer->payload.data[0];
230
231         zfcp_san_dbf_event_incoming_els(fsf_req);
232         if (els_type == LS_PLOGI)
233                 zfcp_fc_incoming_plogi(fsf_req);
234         else if (els_type == LS_LOGO)
235                 zfcp_fc_incoming_logo(fsf_req);
236         else if (els_type == LS_RSCN)
237                 zfcp_fc_incoming_rscn(fsf_req);
238 }
239
240 static void zfcp_fc_ns_handler(unsigned long data)
241 {
242         struct zfcp_fc_ns_handler_data *compl_rec =
243                         (struct zfcp_fc_ns_handler_data *) data;
244
245         if (compl_rec->handler)
246                 compl_rec->handler(compl_rec->handler_data);
247
248         complete(&compl_rec->done);
249 }
250
251 static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
252 {
253         struct zfcp_gid_pn_data *gid_pn = (struct zfcp_gid_pn_data *) data;
254         struct zfcp_send_ct *ct = &gid_pn->ct;
255         struct ct_iu_gid_pn_req *ct_iu_req = sg_virt(ct->req);
256         struct ct_iu_gid_pn_resp *ct_iu_resp = sg_virt(ct->resp);
257         struct zfcp_port *port = gid_pn->port;
258
259         if (ct->status)
260                 return;
261         if (ct_iu_resp->header.cmd_rsp_code != ZFCP_CT_ACCEPT)
262                 return;
263
264         /* paranoia */
265         if (ct_iu_req->wwpn != port->wwpn)
266                 return;
267         /* looks like a valid d_id */
268         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
269 }
270
271 int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
272                                      struct zfcp_gid_pn_data *gid_pn)
273 {
274         struct zfcp_adapter *adapter = erp_action->adapter;
275         struct zfcp_fc_ns_handler_data compl_rec;
276         int ret;
277
278         /* setup parameters for send generic command */
279         gid_pn->port = erp_action->port;
280         gid_pn->ct.wka_port = &adapter->nsp;
281         gid_pn->ct.handler = zfcp_fc_ns_handler;
282         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
283         gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
284         gid_pn->ct.req = &gid_pn->req;
285         gid_pn->ct.resp = &gid_pn->resp;
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_SIZE_ONE_PAGE / 4;
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, ZFCP_STATUS_COMMON_ERP_FAILED,
377                                             "fcadh_1", NULL);
378                 goto out;
379         }
380
381         if (!port->wwnn)
382                 port->wwnn = ls_adisc->wwnn;
383
384         if ((port->wwpn != ls_adisc->wwpn) ||
385             !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)) {
386                 zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
387                                      "fcadh_2", NULL);
388                 goto out;
389         }
390
391         /* port is good, unblock rport without going through erp */
392         zfcp_scsi_schedule_rport_register(port);
393  out:
394         zfcp_port_put(port);
395         kfree(adisc);
396 }
397
398 static int zfcp_fc_adisc(struct zfcp_port *port)
399 {
400         struct zfcp_els_adisc *adisc;
401         struct zfcp_adapter *adapter = port->adapter;
402
403         adisc = kzalloc(sizeof(struct zfcp_els_adisc), GFP_ATOMIC);
404         if (!adisc)
405                 return -ENOMEM;
406
407         adisc->els.req = &adisc->req;
408         adisc->els.resp = &adisc->resp;
409         sg_init_one(adisc->els.req, &adisc->ls_adisc,
410                     sizeof(struct zfcp_ls_adisc));
411         sg_init_one(adisc->els.resp, &adisc->ls_adisc_acc,
412                     sizeof(struct zfcp_ls_adisc));
413
414         adisc->els.adapter = adapter;
415         adisc->els.port = port;
416         adisc->els.d_id = port->d_id;
417         adisc->els.handler = zfcp_fc_adisc_handler;
418         adisc->els.handler_data = (unsigned long) adisc;
419         adisc->els.ls_code = adisc->ls_adisc.code = ZFCP_LS_ADISC;
420
421         /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
422            without FC-AL-2 capability, so we don't set it */
423         adisc->ls_adisc.wwpn = fc_host_port_name(adapter->scsi_host);
424         adisc->ls_adisc.wwnn = fc_host_node_name(adapter->scsi_host);
425         adisc->ls_adisc.nport_id = fc_host_port_id(adapter->scsi_host);
426
427         return zfcp_fsf_send_els(&adisc->els);
428 }
429
430 void zfcp_fc_link_test_work(struct work_struct *work)
431 {
432         struct zfcp_port *port =
433                 container_of(work, struct zfcp_port, test_link_work);
434         int retval;
435
436         zfcp_port_get(port);
437         port->rport_task = RPORT_DEL;
438         zfcp_scsi_rport_work(&port->rport_work);
439
440         retval = zfcp_fc_adisc(port);
441         if (retval == 0)
442                 return;
443
444         /* send of ADISC was not possible */
445         zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
446
447         zfcp_port_put(port);
448 }
449
450 /**
451  * zfcp_test_link - lightweight link test procedure
452  * @port: port to be tested
453  *
454  * Test status of a link to a remote port using the ELS command ADISC.
455  * If there is a problem with the remote port, error recovery steps
456  * will be triggered.
457  */
458 void zfcp_test_link(struct zfcp_port *port)
459 {
460         zfcp_port_get(port);
461         if (!queue_work(zfcp_data.work_queue, &port->test_link_work))
462                 zfcp_port_put(port);
463 }
464
465 static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft, int buf_num)
466 {
467         struct scatterlist *sg = &gpn_ft->sg_req;
468
469         kfree(sg_virt(sg)); /* free request buffer */
470         zfcp_sg_free_table(gpn_ft->sg_resp, buf_num);
471
472         kfree(gpn_ft);
473 }
474
475 static struct zfcp_gpn_ft *zfcp_alloc_sg_env(int buf_num)
476 {
477         struct zfcp_gpn_ft *gpn_ft;
478         struct ct_iu_gpn_ft_req *req;
479
480         gpn_ft = kzalloc(sizeof(*gpn_ft), GFP_KERNEL);
481         if (!gpn_ft)
482                 return NULL;
483
484         req = kzalloc(sizeof(struct ct_iu_gpn_ft_req), GFP_KERNEL);
485         if (!req) {
486                 kfree(gpn_ft);
487                 gpn_ft = NULL;
488                 goto out;
489         }
490         sg_init_one(&gpn_ft->sg_req, req, sizeof(*req));
491
492         if (zfcp_sg_setup_table(gpn_ft->sg_resp, buf_num)) {
493                 zfcp_free_sg_env(gpn_ft, buf_num);
494                 gpn_ft = NULL;
495         }
496 out:
497         return gpn_ft;
498 }
499
500
501 static int zfcp_scan_issue_gpn_ft(struct zfcp_gpn_ft *gpn_ft,
502                                   struct zfcp_adapter *adapter,
503                                   int max_bytes)
504 {
505         struct zfcp_send_ct *ct = &gpn_ft->ct;
506         struct ct_iu_gpn_ft_req *req = sg_virt(&gpn_ft->sg_req);
507         struct zfcp_fc_ns_handler_data compl_rec;
508         int ret;
509
510         /* prepare CT IU for GPN_FT */
511         req->header.revision = ZFCP_CT_REVISION;
512         req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
513         req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
514         req->header.options = ZFCP_CT_SYNCHRONOUS;
515         req->header.cmd_rsp_code = ZFCP_CT_GPN_FT;
516         req->header.max_res_size = max_bytes / 4;
517         req->flags = 0;
518         req->domain_id_scope = 0;
519         req->area_id_scope = 0;
520         req->fc4_type = ZFCP_CT_SCSI_FCP;
521
522         /* prepare zfcp_send_ct */
523         ct->wka_port = &adapter->nsp;
524         ct->handler = zfcp_fc_ns_handler;
525         ct->handler_data = (unsigned long)&compl_rec;
526         ct->timeout = 10;
527         ct->req = &gpn_ft->sg_req;
528         ct->resp = gpn_ft->sg_resp;
529
530         init_completion(&compl_rec.done);
531         compl_rec.handler = NULL;
532         ret = zfcp_fsf_send_ct(ct, NULL, NULL);
533         if (!ret)
534                 wait_for_completion(&compl_rec.done);
535         return ret;
536 }
537
538 static void zfcp_validate_port(struct zfcp_port *port)
539 {
540         struct zfcp_adapter *adapter = port->adapter;
541
542         if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC))
543                 return;
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                         continue;
607
608                 port = zfcp_port_enqueue(adapter, acc->wwpn,
609                                          ZFCP_STATUS_COMMON_NOESC, d_id);
610                 if (IS_ERR(port))
611                         ret = PTR_ERR(port);
612                 else
613                         zfcp_erp_port_reopen(port, 0, "fcegpf1", NULL);
614         }
615
616         zfcp_erp_wait(adapter);
617         list_for_each_entry_safe(port, tmp, &adapter->port_list_head, list)
618                 zfcp_validate_port(port);
619         up(&zfcp_data.config_sema);
620         return ret;
621 }
622
623 /**
624  * zfcp_scan_ports - scan remote ports and attach new ports
625  * @adapter: pointer to struct zfcp_adapter
626  */
627 int zfcp_scan_ports(struct zfcp_adapter *adapter)
628 {
629         int ret, i;
630         struct zfcp_gpn_ft *gpn_ft;
631         int chain, max_entries, buf_num, max_bytes;
632
633         chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
634         buf_num = chain ? ZFCP_GPN_FT_BUFFERS : 1;
635         max_entries = chain ? ZFCP_GPN_FT_MAX_ENTRIES : ZFCP_GPN_FT_ENTRIES;
636         max_bytes = chain ? ZFCP_GPN_FT_MAX_SIZE : ZFCP_CT_SIZE_ONE_PAGE;
637
638         if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT &&
639             fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPIV)
640                 return 0;
641
642         ret = zfcp_wka_port_get(&adapter->nsp);
643         if (ret)
644                 return ret;
645
646         gpn_ft = zfcp_alloc_sg_env(buf_num);
647         if (!gpn_ft) {
648                 ret = -ENOMEM;
649                 goto out;
650         }
651
652         for (i = 0; i < 3; i++) {
653                 ret = zfcp_scan_issue_gpn_ft(gpn_ft, adapter, max_bytes);
654                 if (!ret) {
655                         ret = zfcp_scan_eval_gpn_ft(gpn_ft, max_entries);
656                         if (ret == -EAGAIN)
657                                 ssleep(1);
658                         else
659                                 break;
660                 }
661         }
662         zfcp_free_sg_env(gpn_ft, buf_num);
663 out:
664         zfcp_wka_port_put(&adapter->nsp);
665         return ret;
666 }
667
668
669 void _zfcp_scan_ports_later(struct work_struct *work)
670 {
671         zfcp_scan_ports(container_of(work, struct zfcp_adapter, scan_work));
672 }