[SCSI] zfcp: avoid false ERP complete due to sema race
[linux-2.6.git] / drivers / s390 / scsi / zfcp_erp.c
1 /*
2  * zfcp device driver
3  *
4  * Error Recovery Procedures (ERP).
5  *
6  * Copyright IBM Corporation 2002, 2009
7  */
8
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12 #include "zfcp_ext.h"
13
14 #define ZFCP_MAX_ERPS                   3
15
16 enum zfcp_erp_act_flags {
17         ZFCP_STATUS_ERP_TIMEDOUT        = 0x10000000,
18         ZFCP_STATUS_ERP_CLOSE_ONLY      = 0x01000000,
19         ZFCP_STATUS_ERP_DISMISSING      = 0x00100000,
20         ZFCP_STATUS_ERP_DISMISSED       = 0x00200000,
21         ZFCP_STATUS_ERP_LOWMEM          = 0x00400000,
22 };
23
24 enum zfcp_erp_steps {
25         ZFCP_ERP_STEP_UNINITIALIZED     = 0x0000,
26         ZFCP_ERP_STEP_FSF_XCONFIG       = 0x0001,
27         ZFCP_ERP_STEP_PHYS_PORT_CLOSING = 0x0010,
28         ZFCP_ERP_STEP_PORT_CLOSING      = 0x0100,
29         ZFCP_ERP_STEP_NAMESERVER_LOOKUP = 0x0400,
30         ZFCP_ERP_STEP_PORT_OPENING      = 0x0800,
31         ZFCP_ERP_STEP_UNIT_CLOSING      = 0x1000,
32         ZFCP_ERP_STEP_UNIT_OPENING      = 0x2000,
33 };
34
35 enum zfcp_erp_act_type {
36         ZFCP_ERP_ACTION_REOPEN_UNIT        = 1,
37         ZFCP_ERP_ACTION_REOPEN_PORT        = 2,
38         ZFCP_ERP_ACTION_REOPEN_PORT_FORCED = 3,
39         ZFCP_ERP_ACTION_REOPEN_ADAPTER     = 4,
40 };
41
42 enum zfcp_erp_act_state {
43         ZFCP_ERP_ACTION_RUNNING = 1,
44         ZFCP_ERP_ACTION_READY   = 2,
45 };
46
47 enum zfcp_erp_act_result {
48         ZFCP_ERP_SUCCEEDED = 0,
49         ZFCP_ERP_FAILED    = 1,
50         ZFCP_ERP_CONTINUES = 2,
51         ZFCP_ERP_EXIT      = 3,
52         ZFCP_ERP_DISMISSED = 4,
53         ZFCP_ERP_NOMEM     = 5,
54 };
55
56 static void zfcp_erp_adapter_block(struct zfcp_adapter *adapter, int mask)
57 {
58         zfcp_erp_modify_adapter_status(adapter, "erablk1", NULL,
59                                        ZFCP_STATUS_COMMON_UNBLOCKED | mask,
60                                        ZFCP_CLEAR);
61 }
62
63 static int zfcp_erp_action_exists(struct zfcp_erp_action *act)
64 {
65         struct zfcp_erp_action *curr_act;
66
67         list_for_each_entry(curr_act, &act->adapter->erp_running_head, list)
68                 if (act == curr_act)
69                         return ZFCP_ERP_ACTION_RUNNING;
70         return 0;
71 }
72
73 static void zfcp_erp_action_ready(struct zfcp_erp_action *act)
74 {
75         struct zfcp_adapter *adapter = act->adapter;
76
77         list_move(&act->list, &act->adapter->erp_ready_head);
78         zfcp_rec_dbf_event_action("erardy1", act);
79         up(&adapter->erp_ready_sem);
80         zfcp_rec_dbf_event_thread("erardy2", adapter);
81 }
82
83 static void zfcp_erp_action_dismiss(struct zfcp_erp_action *act)
84 {
85         act->status |= ZFCP_STATUS_ERP_DISMISSED;
86         if (zfcp_erp_action_exists(act) == ZFCP_ERP_ACTION_RUNNING)
87                 zfcp_erp_action_ready(act);
88 }
89
90 static void zfcp_erp_action_dismiss_unit(struct zfcp_unit *unit)
91 {
92         if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
93                 zfcp_erp_action_dismiss(&unit->erp_action);
94 }
95
96 static void zfcp_erp_action_dismiss_port(struct zfcp_port *port)
97 {
98         struct zfcp_unit *unit;
99
100         if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
101                 zfcp_erp_action_dismiss(&port->erp_action);
102         else
103                 list_for_each_entry(unit, &port->unit_list_head, list)
104                     zfcp_erp_action_dismiss_unit(unit);
105 }
106
107 static void zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *adapter)
108 {
109         struct zfcp_port *port;
110
111         if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
112                 zfcp_erp_action_dismiss(&adapter->erp_action);
113         else
114                 list_for_each_entry(port, &adapter->port_list_head, list)
115                     zfcp_erp_action_dismiss_port(port);
116 }
117
118 static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
119                                  struct zfcp_port *port,
120                                  struct zfcp_unit *unit)
121 {
122         int need = want;
123         int u_status, p_status, a_status;
124
125         switch (want) {
126         case ZFCP_ERP_ACTION_REOPEN_UNIT:
127                 u_status = atomic_read(&unit->status);
128                 if (u_status & ZFCP_STATUS_COMMON_ERP_INUSE)
129                         return 0;
130                 p_status = atomic_read(&port->status);
131                 if (!(p_status & ZFCP_STATUS_COMMON_RUNNING) ||
132                       p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
133                         return 0;
134                 if (!(p_status & ZFCP_STATUS_COMMON_UNBLOCKED))
135                         need = ZFCP_ERP_ACTION_REOPEN_PORT;
136                 /* fall through */
137         case ZFCP_ERP_ACTION_REOPEN_PORT:
138         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
139                 p_status = atomic_read(&port->status);
140                 if (p_status & ZFCP_STATUS_COMMON_ERP_INUSE)
141                         return 0;
142                 a_status = atomic_read(&adapter->status);
143                 if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) ||
144                       a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
145                         return 0;
146                 if (!(a_status & ZFCP_STATUS_COMMON_UNBLOCKED))
147                         need = ZFCP_ERP_ACTION_REOPEN_ADAPTER;
148                 /* fall through */
149         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
150                 a_status = atomic_read(&adapter->status);
151                 if (a_status & ZFCP_STATUS_COMMON_ERP_INUSE)
152                         return 0;
153         }
154
155         return need;
156 }
157
158 static struct zfcp_erp_action *zfcp_erp_setup_act(int need,
159                                                   struct zfcp_adapter *adapter,
160                                                   struct zfcp_port *port,
161                                                   struct zfcp_unit *unit)
162 {
163         struct zfcp_erp_action *erp_action;
164         u32 status = 0;
165
166         switch (need) {
167         case ZFCP_ERP_ACTION_REOPEN_UNIT:
168                 zfcp_unit_get(unit);
169                 atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE, &unit->status);
170                 erp_action = &unit->erp_action;
171                 if (!(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_RUNNING))
172                         status = ZFCP_STATUS_ERP_CLOSE_ONLY;
173                 break;
174
175         case ZFCP_ERP_ACTION_REOPEN_PORT:
176         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
177                 zfcp_port_get(port);
178                 zfcp_erp_action_dismiss_port(port);
179                 atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE, &port->status);
180                 erp_action = &port->erp_action;
181                 if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_RUNNING))
182                         status = ZFCP_STATUS_ERP_CLOSE_ONLY;
183                 break;
184
185         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
186                 zfcp_adapter_get(adapter);
187                 zfcp_erp_action_dismiss_adapter(adapter);
188                 atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE, &adapter->status);
189                 erp_action = &adapter->erp_action;
190                 if (!(atomic_read(&adapter->status) &
191                       ZFCP_STATUS_COMMON_RUNNING))
192                         status = ZFCP_STATUS_ERP_CLOSE_ONLY;
193                 break;
194
195         default:
196                 return NULL;
197         }
198
199         memset(erp_action, 0, sizeof(struct zfcp_erp_action));
200         erp_action->adapter = adapter;
201         erp_action->port = port;
202         erp_action->unit = unit;
203         erp_action->action = need;
204         erp_action->status = status;
205
206         return erp_action;
207 }
208
209 static int zfcp_erp_action_enqueue(int want, struct zfcp_adapter *adapter,
210                                    struct zfcp_port *port,
211                                    struct zfcp_unit *unit, char *id, void *ref)
212 {
213         int retval = 1, need;
214         struct zfcp_erp_action *act = NULL;
215
216         if (!(atomic_read(&adapter->status) &
217               ZFCP_STATUS_ADAPTER_ERP_THREAD_UP))
218                 return -EIO;
219
220         need = zfcp_erp_required_act(want, adapter, port, unit);
221         if (!need)
222                 goto out;
223
224         atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_PENDING, &adapter->status);
225         act = zfcp_erp_setup_act(need, adapter, port, unit);
226         if (!act)
227                 goto out;
228         ++adapter->erp_total_count;
229         list_add_tail(&act->list, &adapter->erp_ready_head);
230         up(&adapter->erp_ready_sem);
231         zfcp_rec_dbf_event_thread("eracte1", adapter);
232         retval = 0;
233  out:
234         zfcp_rec_dbf_event_trigger(id, ref, want, need, act,
235                                    adapter, port, unit);
236         return retval;
237 }
238
239 static int _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter,
240                                     int clear_mask, char *id, void *ref)
241 {
242         zfcp_erp_adapter_block(adapter, clear_mask);
243         zfcp_scsi_schedule_rports_block(adapter);
244
245         /* ensure propagation of failed status to new devices */
246         if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
247                 zfcp_erp_adapter_failed(adapter, "erareo1", NULL);
248                 return -EIO;
249         }
250         return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER,
251                                        adapter, NULL, NULL, id, ref);
252 }
253
254 /**
255  * zfcp_erp_adapter_reopen - Reopen adapter.
256  * @adapter: Adapter to reopen.
257  * @clear: Status flags to clear.
258  * @id: Id for debug trace event.
259  * @ref: Reference for debug trace event.
260  */
261 void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear,
262                              char *id, void *ref)
263 {
264         unsigned long flags;
265
266         read_lock_irqsave(&zfcp_data.config_lock, flags);
267         write_lock(&adapter->erp_lock);
268         _zfcp_erp_adapter_reopen(adapter, clear, id, ref);
269         write_unlock(&adapter->erp_lock);
270         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
271 }
272
273 /**
274  * zfcp_erp_adapter_shutdown - Shutdown adapter.
275  * @adapter: Adapter to shut down.
276  * @clear: Status flags to clear.
277  * @id: Id for debug trace event.
278  * @ref: Reference for debug trace event.
279  */
280 void zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear,
281                                char *id, void *ref)
282 {
283         int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
284         zfcp_erp_adapter_reopen(adapter, clear | flags, id, ref);
285 }
286
287 /**
288  * zfcp_erp_port_shutdown - Shutdown port
289  * @port: Port to shut down.
290  * @clear: Status flags to clear.
291  * @id: Id for debug trace event.
292  * @ref: Reference for debug trace event.
293  */
294 void zfcp_erp_port_shutdown(struct zfcp_port *port, int clear, char *id,
295                             void *ref)
296 {
297         int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
298         zfcp_erp_port_reopen(port, clear | flags, id, ref);
299 }
300
301 /**
302  * zfcp_erp_unit_shutdown - Shutdown unit
303  * @unit: Unit to shut down.
304  * @clear: Status flags to clear.
305  * @id: Id for debug trace event.
306  * @ref: Reference for debug trace event.
307  */
308 void zfcp_erp_unit_shutdown(struct zfcp_unit *unit, int clear, char *id,
309                             void *ref)
310 {
311         int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
312         zfcp_erp_unit_reopen(unit, clear | flags, id, ref);
313 }
314
315 static void zfcp_erp_port_block(struct zfcp_port *port, int clear)
316 {
317         zfcp_erp_modify_port_status(port, "erpblk1", NULL,
318                                     ZFCP_STATUS_COMMON_UNBLOCKED | clear,
319                                     ZFCP_CLEAR);
320 }
321
322 static void _zfcp_erp_port_forced_reopen(struct zfcp_port *port,
323                                          int clear, char *id, void *ref)
324 {
325         zfcp_erp_port_block(port, clear);
326         zfcp_scsi_schedule_rport_block(port);
327
328         if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
329                 return;
330
331         zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
332                                 port->adapter, port, NULL, id, ref);
333 }
334
335 /**
336  * zfcp_erp_port_forced_reopen - Forced close of port and open again
337  * @port: Port to force close and to reopen.
338  * @id: Id for debug trace event.
339  * @ref: Reference for debug trace event.
340  */
341 void zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear, char *id,
342                                  void *ref)
343 {
344         unsigned long flags;
345         struct zfcp_adapter *adapter = port->adapter;
346
347         read_lock_irqsave(&zfcp_data.config_lock, flags);
348         write_lock(&adapter->erp_lock);
349         _zfcp_erp_port_forced_reopen(port, clear, id, ref);
350         write_unlock(&adapter->erp_lock);
351         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
352 }
353
354 static int _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id,
355                                  void *ref)
356 {
357         zfcp_erp_port_block(port, clear);
358         zfcp_scsi_schedule_rport_block(port);
359
360         if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
361                 /* ensure propagation of failed status to new devices */
362                 zfcp_erp_port_failed(port, "erpreo1", NULL);
363                 return -EIO;
364         }
365
366         return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT,
367                                        port->adapter, port, NULL, id, ref);
368 }
369
370 /**
371  * zfcp_erp_port_reopen - trigger remote port recovery
372  * @port: port to recover
373  * @clear_mask: flags in port status to be cleared
374  *
375  * Returns 0 if recovery has been triggered, < 0 if not.
376  */
377 int zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id, void *ref)
378 {
379         unsigned long flags;
380         int retval;
381         struct zfcp_adapter *adapter = port->adapter;
382
383         read_lock_irqsave(&zfcp_data.config_lock, flags);
384         write_lock(&adapter->erp_lock);
385         retval = _zfcp_erp_port_reopen(port, clear, id, ref);
386         write_unlock(&adapter->erp_lock);
387         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
388
389         return retval;
390 }
391
392 static void zfcp_erp_unit_block(struct zfcp_unit *unit, int clear_mask)
393 {
394         zfcp_erp_modify_unit_status(unit, "erublk1", NULL,
395                                     ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask,
396                                     ZFCP_CLEAR);
397 }
398
399 static void _zfcp_erp_unit_reopen(struct zfcp_unit *unit, int clear, char *id,
400                                   void *ref)
401 {
402         struct zfcp_adapter *adapter = unit->port->adapter;
403
404         zfcp_erp_unit_block(unit, clear);
405
406         if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
407                 return;
408
409         zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_UNIT,
410                                 adapter, unit->port, unit, id, ref);
411 }
412
413 /**
414  * zfcp_erp_unit_reopen - initiate reopen of a unit
415  * @unit: unit to be reopened
416  * @clear_mask: specifies flags in unit status to be cleared
417  * Return: 0 on success, < 0 on error
418  */
419 void zfcp_erp_unit_reopen(struct zfcp_unit *unit, int clear, char *id,
420                           void *ref)
421 {
422         unsigned long flags;
423         struct zfcp_port *port = unit->port;
424         struct zfcp_adapter *adapter = port->adapter;
425
426         read_lock_irqsave(&zfcp_data.config_lock, flags);
427         write_lock(&adapter->erp_lock);
428         _zfcp_erp_unit_reopen(unit, clear, id, ref);
429         write_unlock(&adapter->erp_lock);
430         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
431 }
432
433 static int status_change_set(unsigned long mask, atomic_t *status)
434 {
435         return (atomic_read(status) ^ mask) & mask;
436 }
437
438 static int status_change_clear(unsigned long mask, atomic_t *status)
439 {
440         return atomic_read(status) & mask;
441 }
442
443 static void zfcp_erp_adapter_unblock(struct zfcp_adapter *adapter)
444 {
445         if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status))
446                 zfcp_rec_dbf_event_adapter("eraubl1", NULL, adapter);
447         atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status);
448 }
449
450 static void zfcp_erp_port_unblock(struct zfcp_port *port)
451 {
452         if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status))
453                 zfcp_rec_dbf_event_port("erpubl1", NULL, port);
454         atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status);
455 }
456
457 static void zfcp_erp_unit_unblock(struct zfcp_unit *unit)
458 {
459         if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status))
460                 zfcp_rec_dbf_event_unit("eruubl1", NULL, unit);
461         atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &unit->status);
462 }
463
464 static void zfcp_erp_action_to_running(struct zfcp_erp_action *erp_action)
465 {
466         list_move(&erp_action->list, &erp_action->adapter->erp_running_head);
467         zfcp_rec_dbf_event_action("erator1", erp_action);
468 }
469
470 static void zfcp_erp_strategy_check_fsfreq(struct zfcp_erp_action *act)
471 {
472         struct zfcp_adapter *adapter = act->adapter;
473
474         if (!act->fsf_req)
475                 return;
476
477         spin_lock(&adapter->req_list_lock);
478         if (zfcp_reqlist_find_safe(adapter, act->fsf_req) &&
479             act->fsf_req->erp_action == act) {
480                 if (act->status & (ZFCP_STATUS_ERP_DISMISSED |
481                                    ZFCP_STATUS_ERP_TIMEDOUT)) {
482                         act->fsf_req->status |= ZFCP_STATUS_FSFREQ_DISMISSED;
483                         zfcp_rec_dbf_event_action("erscf_1", act);
484                         act->fsf_req->erp_action = NULL;
485                 }
486                 if (act->status & ZFCP_STATUS_ERP_TIMEDOUT)
487                         zfcp_rec_dbf_event_action("erscf_2", act);
488                 if (act->fsf_req->status & (ZFCP_STATUS_FSFREQ_COMPLETED |
489                                             ZFCP_STATUS_FSFREQ_DISMISSED))
490                         act->fsf_req = NULL;
491         } else
492                 act->fsf_req = NULL;
493         spin_unlock(&adapter->req_list_lock);
494 }
495
496 /**
497  * zfcp_erp_notify - Trigger ERP action.
498  * @erp_action: ERP action to continue.
499  * @set_mask: ERP action status flags to set.
500  */
501 void zfcp_erp_notify(struct zfcp_erp_action *erp_action, unsigned long set_mask)
502 {
503         struct zfcp_adapter *adapter = erp_action->adapter;
504         unsigned long flags;
505
506         write_lock_irqsave(&adapter->erp_lock, flags);
507         if (zfcp_erp_action_exists(erp_action) == ZFCP_ERP_ACTION_RUNNING) {
508                 erp_action->status |= set_mask;
509                 zfcp_erp_action_ready(erp_action);
510         }
511         write_unlock_irqrestore(&adapter->erp_lock, flags);
512 }
513
514 /**
515  * zfcp_erp_timeout_handler - Trigger ERP action from timed out ERP request
516  * @data: ERP action (from timer data)
517  */
518 void zfcp_erp_timeout_handler(unsigned long data)
519 {
520         struct zfcp_erp_action *act = (struct zfcp_erp_action *) data;
521         zfcp_erp_notify(act, ZFCP_STATUS_ERP_TIMEDOUT);
522 }
523
524 static void zfcp_erp_memwait_handler(unsigned long data)
525 {
526         zfcp_erp_notify((struct zfcp_erp_action *)data, 0);
527 }
528
529 static void zfcp_erp_strategy_memwait(struct zfcp_erp_action *erp_action)
530 {
531         init_timer(&erp_action->timer);
532         erp_action->timer.function = zfcp_erp_memwait_handler;
533         erp_action->timer.data = (unsigned long) erp_action;
534         erp_action->timer.expires = jiffies + HZ;
535         add_timer(&erp_action->timer);
536 }
537
538 static void _zfcp_erp_port_reopen_all(struct zfcp_adapter *adapter,
539                                       int clear, char *id, void *ref)
540 {
541         struct zfcp_port *port;
542
543         list_for_each_entry(port, &adapter->port_list_head, list)
544                 _zfcp_erp_port_reopen(port, clear, id, ref);
545 }
546
547 static void _zfcp_erp_unit_reopen_all(struct zfcp_port *port, int clear,
548                                       char *id, void *ref)
549 {
550         struct zfcp_unit *unit;
551
552         list_for_each_entry(unit, &port->unit_list_head, list)
553                 _zfcp_erp_unit_reopen(unit, clear, id, ref);
554 }
555
556 static void zfcp_erp_strategy_followup_actions(struct zfcp_erp_action *act)
557 {
558         struct zfcp_adapter *adapter = act->adapter;
559         struct zfcp_port *port = act->port;
560         struct zfcp_unit *unit = act->unit;
561         u32 status = act->status;
562
563         /* initiate follow-up actions depending on success of finished action */
564         switch (act->action) {
565
566         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
567                 if (status == ZFCP_ERP_SUCCEEDED)
568                         _zfcp_erp_port_reopen_all(adapter, 0, "ersfa_1", NULL);
569                 else
570                         _zfcp_erp_adapter_reopen(adapter, 0, "ersfa_2", NULL);
571                 break;
572
573         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
574                 if (status == ZFCP_ERP_SUCCEEDED)
575                         _zfcp_erp_port_reopen(port, 0, "ersfa_3", NULL);
576                 else
577                         _zfcp_erp_adapter_reopen(adapter, 0, "ersfa_4", NULL);
578                 break;
579
580         case ZFCP_ERP_ACTION_REOPEN_PORT:
581                 if (status == ZFCP_ERP_SUCCEEDED)
582                         _zfcp_erp_unit_reopen_all(port, 0, "ersfa_5", NULL);
583                 else
584                         _zfcp_erp_port_forced_reopen(port, 0, "ersfa_6", NULL);
585                 break;
586
587         case ZFCP_ERP_ACTION_REOPEN_UNIT:
588                 if (status != ZFCP_ERP_SUCCEEDED)
589                         _zfcp_erp_port_reopen(unit->port, 0, "ersfa_7", NULL);
590                 break;
591         }
592 }
593
594 static void zfcp_erp_wakeup(struct zfcp_adapter *adapter)
595 {
596         unsigned long flags;
597
598         read_lock_irqsave(&zfcp_data.config_lock, flags);
599         read_lock(&adapter->erp_lock);
600         if (list_empty(&adapter->erp_ready_head) &&
601             list_empty(&adapter->erp_running_head)) {
602                         atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_PENDING,
603                                           &adapter->status);
604                         wake_up(&adapter->erp_done_wqh);
605         }
606         read_unlock(&adapter->erp_lock);
607         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
608 }
609
610 static int zfcp_erp_adapter_strategy_open_qdio(struct zfcp_erp_action *act)
611 {
612         if (zfcp_qdio_open(act->adapter))
613                 return ZFCP_ERP_FAILED;
614         init_waitqueue_head(&act->adapter->request_wq);
615         atomic_set_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &act->adapter->status);
616         return ZFCP_ERP_SUCCEEDED;
617 }
618
619 static void zfcp_erp_enqueue_ptp_port(struct zfcp_adapter *adapter)
620 {
621         struct zfcp_port *port;
622         port = zfcp_port_enqueue(adapter, adapter->peer_wwpn, 0,
623                                  adapter->peer_d_id);
624         if (IS_ERR(port)) /* error or port already attached */
625                 return;
626         _zfcp_erp_port_reopen(port, 0, "ereptp1", NULL);
627 }
628
629 static int zfcp_erp_adapter_strat_fsf_xconf(struct zfcp_erp_action *erp_action)
630 {
631         int retries;
632         int sleep = 1;
633         struct zfcp_adapter *adapter = erp_action->adapter;
634
635         atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK, &adapter->status);
636
637         for (retries = 7; retries; retries--) {
638                 atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
639                                   &adapter->status);
640                 write_lock_irq(&adapter->erp_lock);
641                 zfcp_erp_action_to_running(erp_action);
642                 write_unlock_irq(&adapter->erp_lock);
643                 if (zfcp_fsf_exchange_config_data(erp_action)) {
644                         atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
645                                           &adapter->status);
646                         return ZFCP_ERP_FAILED;
647                 }
648
649                 zfcp_rec_dbf_event_thread_lock("erasfx1", adapter);
650                 down(&adapter->erp_ready_sem);
651                 zfcp_rec_dbf_event_thread_lock("erasfx2", adapter);
652                 if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT)
653                         break;
654
655                 if (!(atomic_read(&adapter->status) &
656                       ZFCP_STATUS_ADAPTER_HOST_CON_INIT))
657                         break;
658
659                 ssleep(sleep);
660                 sleep *= 2;
661         }
662
663         atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
664                           &adapter->status);
665
666         if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_XCONFIG_OK))
667                 return ZFCP_ERP_FAILED;
668
669         if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
670                 zfcp_erp_enqueue_ptp_port(adapter);
671
672         return ZFCP_ERP_SUCCEEDED;
673 }
674
675 static int zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *act)
676 {
677         int ret;
678         struct zfcp_adapter *adapter = act->adapter;
679
680         write_lock_irq(&adapter->erp_lock);
681         zfcp_erp_action_to_running(act);
682         write_unlock_irq(&adapter->erp_lock);
683
684         ret = zfcp_fsf_exchange_port_data(act);
685         if (ret == -EOPNOTSUPP)
686                 return ZFCP_ERP_SUCCEEDED;
687         if (ret)
688                 return ZFCP_ERP_FAILED;
689
690         zfcp_rec_dbf_event_thread_lock("erasox1", adapter);
691         down(&adapter->erp_ready_sem);
692         zfcp_rec_dbf_event_thread_lock("erasox2", adapter);
693         if (act->status & ZFCP_STATUS_ERP_TIMEDOUT)
694                 return ZFCP_ERP_FAILED;
695
696         return ZFCP_ERP_SUCCEEDED;
697 }
698
699 static int zfcp_erp_adapter_strategy_open_fsf(struct zfcp_erp_action *act)
700 {
701         if (zfcp_erp_adapter_strat_fsf_xconf(act) == ZFCP_ERP_FAILED)
702                 return ZFCP_ERP_FAILED;
703
704         if (zfcp_erp_adapter_strategy_open_fsf_xport(act) == ZFCP_ERP_FAILED)
705                 return ZFCP_ERP_FAILED;
706
707         atomic_set(&act->adapter->stat_miss, 16);
708         if (zfcp_status_read_refill(act->adapter))
709                 return ZFCP_ERP_FAILED;
710
711         return ZFCP_ERP_SUCCEEDED;
712 }
713
714 static void zfcp_erp_adapter_strategy_close(struct zfcp_erp_action *act)
715 {
716         struct zfcp_adapter *adapter = act->adapter;
717
718         /* close queues to ensure that buffers are not accessed by adapter */
719         zfcp_qdio_close(adapter);
720         zfcp_fsf_req_dismiss_all(adapter);
721         adapter->fsf_req_seq_no = 0;
722         zfcp_fc_wka_port_force_offline(&adapter->nsp);
723         /* all ports and units are closed */
724         zfcp_erp_modify_adapter_status(adapter, "erascl1", NULL,
725                                        ZFCP_STATUS_COMMON_OPEN, ZFCP_CLEAR);
726
727         atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK |
728                           ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status);
729 }
730
731 static int zfcp_erp_adapter_strategy_open(struct zfcp_erp_action *act)
732 {
733         struct zfcp_adapter *adapter = act->adapter;
734
735         if (zfcp_erp_adapter_strategy_open_qdio(act)) {
736                 atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK |
737                                   ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED,
738                                   &adapter->status);
739                 return ZFCP_ERP_FAILED;
740         }
741
742         if (zfcp_erp_adapter_strategy_open_fsf(act)) {
743                 zfcp_erp_adapter_strategy_close(act);
744                 return ZFCP_ERP_FAILED;
745         }
746
747         atomic_set_mask(ZFCP_STATUS_COMMON_OPEN, &adapter->status);
748
749         return ZFCP_ERP_SUCCEEDED;
750 }
751
752 static int zfcp_erp_adapter_strategy(struct zfcp_erp_action *act)
753 {
754         struct zfcp_adapter *adapter = act->adapter;
755
756         if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN) {
757                 zfcp_erp_adapter_strategy_close(act);
758                 if (act->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
759                         return ZFCP_ERP_EXIT;
760         }
761
762         if (zfcp_erp_adapter_strategy_open(act)) {
763                 ssleep(8);
764                 return ZFCP_ERP_FAILED;
765         }
766
767         return ZFCP_ERP_SUCCEEDED;
768 }
769
770 static int zfcp_erp_port_forced_strategy_close(struct zfcp_erp_action *act)
771 {
772         int retval;
773
774         retval = zfcp_fsf_close_physical_port(act);
775         if (retval == -ENOMEM)
776                 return ZFCP_ERP_NOMEM;
777         act->step = ZFCP_ERP_STEP_PHYS_PORT_CLOSING;
778         if (retval)
779                 return ZFCP_ERP_FAILED;
780
781         return ZFCP_ERP_CONTINUES;
782 }
783
784 static void zfcp_erp_port_strategy_clearstati(struct zfcp_port *port)
785 {
786         atomic_clear_mask(ZFCP_STATUS_COMMON_ACCESS_DENIED, &port->status);
787 }
788
789 static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *erp_action)
790 {
791         struct zfcp_port *port = erp_action->port;
792         int status = atomic_read(&port->status);
793
794         switch (erp_action->step) {
795         case ZFCP_ERP_STEP_UNINITIALIZED:
796                 zfcp_erp_port_strategy_clearstati(port);
797                 if ((status & ZFCP_STATUS_PORT_PHYS_OPEN) &&
798                     (status & ZFCP_STATUS_COMMON_OPEN))
799                         return zfcp_erp_port_forced_strategy_close(erp_action);
800                 else
801                         return ZFCP_ERP_FAILED;
802
803         case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
804                 if (status & ZFCP_STATUS_PORT_PHYS_OPEN)
805                         return ZFCP_ERP_SUCCEEDED;
806         }
807         return ZFCP_ERP_FAILED;
808 }
809
810 static int zfcp_erp_port_strategy_close(struct zfcp_erp_action *erp_action)
811 {
812         int retval;
813
814         retval = zfcp_fsf_close_port(erp_action);
815         if (retval == -ENOMEM)
816                 return ZFCP_ERP_NOMEM;
817         erp_action->step = ZFCP_ERP_STEP_PORT_CLOSING;
818         if (retval)
819                 return ZFCP_ERP_FAILED;
820         return ZFCP_ERP_CONTINUES;
821 }
822
823 static int zfcp_erp_port_strategy_open_port(struct zfcp_erp_action *erp_action)
824 {
825         int retval;
826
827         retval = zfcp_fsf_open_port(erp_action);
828         if (retval == -ENOMEM)
829                 return ZFCP_ERP_NOMEM;
830         erp_action->step = ZFCP_ERP_STEP_PORT_OPENING;
831         if (retval)
832                 return ZFCP_ERP_FAILED;
833         return ZFCP_ERP_CONTINUES;
834 }
835
836 static int zfcp_erp_open_ptp_port(struct zfcp_erp_action *act)
837 {
838         struct zfcp_adapter *adapter = act->adapter;
839         struct zfcp_port *port = act->port;
840
841         if (port->wwpn != adapter->peer_wwpn) {
842                 zfcp_erp_port_failed(port, "eroptp1", NULL);
843                 return ZFCP_ERP_FAILED;
844         }
845         port->d_id = adapter->peer_d_id;
846         return zfcp_erp_port_strategy_open_port(act);
847 }
848
849 void zfcp_erp_port_strategy_open_lookup(struct work_struct *work)
850 {
851         int retval;
852         struct zfcp_port *port = container_of(work, struct zfcp_port,
853                                               gid_pn_work);
854
855         retval = zfcp_fc_ns_gid_pn(&port->erp_action);
856         if (retval == -ENOMEM)
857                 zfcp_erp_notify(&port->erp_action, ZFCP_ERP_NOMEM);
858         port->erp_action.step = ZFCP_ERP_STEP_NAMESERVER_LOOKUP;
859         if (retval)
860                 zfcp_erp_notify(&port->erp_action, ZFCP_ERP_FAILED);
861         zfcp_port_put(port);
862 }
863
864 static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
865 {
866         struct zfcp_adapter *adapter = act->adapter;
867         struct zfcp_port *port = act->port;
868         int p_status = atomic_read(&port->status);
869
870         switch (act->step) {
871         case ZFCP_ERP_STEP_UNINITIALIZED:
872         case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
873         case ZFCP_ERP_STEP_PORT_CLOSING:
874                 if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
875                         return zfcp_erp_open_ptp_port(act);
876                 if (!port->d_id) {
877                         zfcp_port_get(port);
878                         if (!queue_work(zfcp_data.work_queue,
879                                         &port->gid_pn_work))
880                                 zfcp_port_put(port);
881                         return ZFCP_ERP_CONTINUES;
882                 }
883         case ZFCP_ERP_STEP_NAMESERVER_LOOKUP:
884                 if (!port->d_id)
885                         return ZFCP_ERP_FAILED;
886                 return zfcp_erp_port_strategy_open_port(act);
887
888         case ZFCP_ERP_STEP_PORT_OPENING:
889                 /* D_ID might have changed during open */
890                 if (p_status & ZFCP_STATUS_COMMON_OPEN) {
891                         if (port->d_id)
892                                 return ZFCP_ERP_SUCCEEDED;
893                         else {
894                                 act->step = ZFCP_ERP_STEP_PORT_CLOSING;
895                                 return ZFCP_ERP_CONTINUES;
896                         }
897                 /* fall through otherwise */
898                 }
899         }
900         return ZFCP_ERP_FAILED;
901 }
902
903 static int zfcp_erp_port_strategy(struct zfcp_erp_action *erp_action)
904 {
905         struct zfcp_port *port = erp_action->port;
906
907         if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC)
908                 goto close_init_done;
909
910         switch (erp_action->step) {
911         case ZFCP_ERP_STEP_UNINITIALIZED:
912                 zfcp_erp_port_strategy_clearstati(port);
913                 if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)
914                         return zfcp_erp_port_strategy_close(erp_action);
915                 break;
916
917         case ZFCP_ERP_STEP_PORT_CLOSING:
918                 if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN)
919                         return ZFCP_ERP_FAILED;
920                 break;
921         }
922
923 close_init_done:
924         if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
925                 return ZFCP_ERP_EXIT;
926
927         return zfcp_erp_port_strategy_open_common(erp_action);
928 }
929
930 static void zfcp_erp_unit_strategy_clearstati(struct zfcp_unit *unit)
931 {
932         atomic_clear_mask(ZFCP_STATUS_COMMON_ACCESS_DENIED |
933                           ZFCP_STATUS_UNIT_SHARED |
934                           ZFCP_STATUS_UNIT_READONLY,
935                           &unit->status);
936 }
937
938 static int zfcp_erp_unit_strategy_close(struct zfcp_erp_action *erp_action)
939 {
940         int retval = zfcp_fsf_close_unit(erp_action);
941         if (retval == -ENOMEM)
942                 return ZFCP_ERP_NOMEM;
943         erp_action->step = ZFCP_ERP_STEP_UNIT_CLOSING;
944         if (retval)
945                 return ZFCP_ERP_FAILED;
946         return ZFCP_ERP_CONTINUES;
947 }
948
949 static int zfcp_erp_unit_strategy_open(struct zfcp_erp_action *erp_action)
950 {
951         int retval = zfcp_fsf_open_unit(erp_action);
952         if (retval == -ENOMEM)
953                 return ZFCP_ERP_NOMEM;
954         erp_action->step = ZFCP_ERP_STEP_UNIT_OPENING;
955         if (retval)
956                 return  ZFCP_ERP_FAILED;
957         return ZFCP_ERP_CONTINUES;
958 }
959
960 static int zfcp_erp_unit_strategy(struct zfcp_erp_action *erp_action)
961 {
962         struct zfcp_unit *unit = erp_action->unit;
963
964         switch (erp_action->step) {
965         case ZFCP_ERP_STEP_UNINITIALIZED:
966                 zfcp_erp_unit_strategy_clearstati(unit);
967                 if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_OPEN)
968                         return zfcp_erp_unit_strategy_close(erp_action);
969                 /* already closed, fall through */
970         case ZFCP_ERP_STEP_UNIT_CLOSING:
971                 if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_OPEN)
972                         return ZFCP_ERP_FAILED;
973                 if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
974                         return ZFCP_ERP_EXIT;
975                 return zfcp_erp_unit_strategy_open(erp_action);
976
977         case ZFCP_ERP_STEP_UNIT_OPENING:
978                 if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_OPEN)
979                         return ZFCP_ERP_SUCCEEDED;
980         }
981         return ZFCP_ERP_FAILED;
982 }
983
984 static int zfcp_erp_strategy_check_unit(struct zfcp_unit *unit, int result)
985 {
986         switch (result) {
987         case ZFCP_ERP_SUCCEEDED :
988                 atomic_set(&unit->erp_counter, 0);
989                 zfcp_erp_unit_unblock(unit);
990                 break;
991         case ZFCP_ERP_FAILED :
992                 atomic_inc(&unit->erp_counter);
993                 if (atomic_read(&unit->erp_counter) > ZFCP_MAX_ERPS) {
994                         dev_err(&unit->port->adapter->ccw_device->dev,
995                                 "ERP failed for unit 0x%016Lx on "
996                                 "port 0x%016Lx\n",
997                                 (unsigned long long)unit->fcp_lun,
998                                 (unsigned long long)unit->port->wwpn);
999                         zfcp_erp_unit_failed(unit, "erusck1", NULL);
1000                 }
1001                 break;
1002         }
1003
1004         if (atomic_read(&unit->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1005                 zfcp_erp_unit_block(unit, 0);
1006                 result = ZFCP_ERP_EXIT;
1007         }
1008         return result;
1009 }
1010
1011 static int zfcp_erp_strategy_check_port(struct zfcp_port *port, int result)
1012 {
1013         switch (result) {
1014         case ZFCP_ERP_SUCCEEDED :
1015                 atomic_set(&port->erp_counter, 0);
1016                 zfcp_erp_port_unblock(port);
1017                 break;
1018
1019         case ZFCP_ERP_FAILED :
1020                 if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC) {
1021                         zfcp_erp_port_block(port, 0);
1022                         result = ZFCP_ERP_EXIT;
1023                 }
1024                 atomic_inc(&port->erp_counter);
1025                 if (atomic_read(&port->erp_counter) > ZFCP_MAX_ERPS) {
1026                         dev_err(&port->adapter->ccw_device->dev,
1027                                 "ERP failed for remote port 0x%016Lx\n",
1028                                 (unsigned long long)port->wwpn);
1029                         zfcp_erp_port_failed(port, "erpsck1", NULL);
1030                 }
1031                 break;
1032         }
1033
1034         if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1035                 zfcp_erp_port_block(port, 0);
1036                 result = ZFCP_ERP_EXIT;
1037         }
1038         return result;
1039 }
1040
1041 static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *adapter,
1042                                            int result)
1043 {
1044         switch (result) {
1045         case ZFCP_ERP_SUCCEEDED :
1046                 atomic_set(&adapter->erp_counter, 0);
1047                 zfcp_erp_adapter_unblock(adapter);
1048                 break;
1049
1050         case ZFCP_ERP_FAILED :
1051                 atomic_inc(&adapter->erp_counter);
1052                 if (atomic_read(&adapter->erp_counter) > ZFCP_MAX_ERPS) {
1053                         dev_err(&adapter->ccw_device->dev,
1054                                 "ERP cannot recover an error "
1055                                 "on the FCP device\n");
1056                         zfcp_erp_adapter_failed(adapter, "erasck1", NULL);
1057                 }
1058                 break;
1059         }
1060
1061         if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1062                 zfcp_erp_adapter_block(adapter, 0);
1063                 result = ZFCP_ERP_EXIT;
1064         }
1065         return result;
1066 }
1067
1068 static int zfcp_erp_strategy_check_target(struct zfcp_erp_action *erp_action,
1069                                           int result)
1070 {
1071         struct zfcp_adapter *adapter = erp_action->adapter;
1072         struct zfcp_port *port = erp_action->port;
1073         struct zfcp_unit *unit = erp_action->unit;
1074
1075         switch (erp_action->action) {
1076
1077         case ZFCP_ERP_ACTION_REOPEN_UNIT:
1078                 result = zfcp_erp_strategy_check_unit(unit, result);
1079                 break;
1080
1081         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1082         case ZFCP_ERP_ACTION_REOPEN_PORT:
1083                 result = zfcp_erp_strategy_check_port(port, result);
1084                 break;
1085
1086         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1087                 result = zfcp_erp_strategy_check_adapter(adapter, result);
1088                 break;
1089         }
1090         return result;
1091 }
1092
1093 static int zfcp_erp_strat_change_det(atomic_t *target_status, u32 erp_status)
1094 {
1095         int status = atomic_read(target_status);
1096
1097         if ((status & ZFCP_STATUS_COMMON_RUNNING) &&
1098             (erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY))
1099                 return 1; /* take it online */
1100
1101         if (!(status & ZFCP_STATUS_COMMON_RUNNING) &&
1102             !(erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY))
1103                 return 1; /* take it offline */
1104
1105         return 0;
1106 }
1107
1108 static int zfcp_erp_strategy_statechange(struct zfcp_erp_action *act, int ret)
1109 {
1110         int action = act->action;
1111         struct zfcp_adapter *adapter = act->adapter;
1112         struct zfcp_port *port = act->port;
1113         struct zfcp_unit *unit = act->unit;
1114         u32 erp_status = act->status;
1115
1116         switch (action) {
1117         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1118                 if (zfcp_erp_strat_change_det(&adapter->status, erp_status)) {
1119                         _zfcp_erp_adapter_reopen(adapter,
1120                                                  ZFCP_STATUS_COMMON_ERP_FAILED,
1121                                                  "ersscg1", NULL);
1122                         return ZFCP_ERP_EXIT;
1123                 }
1124                 break;
1125
1126         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1127         case ZFCP_ERP_ACTION_REOPEN_PORT:
1128                 if (zfcp_erp_strat_change_det(&port->status, erp_status)) {
1129                         _zfcp_erp_port_reopen(port,
1130                                               ZFCP_STATUS_COMMON_ERP_FAILED,
1131                                               "ersscg2", NULL);
1132                         return ZFCP_ERP_EXIT;
1133                 }
1134                 break;
1135
1136         case ZFCP_ERP_ACTION_REOPEN_UNIT:
1137                 if (zfcp_erp_strat_change_det(&unit->status, erp_status)) {
1138                         _zfcp_erp_unit_reopen(unit,
1139                                               ZFCP_STATUS_COMMON_ERP_FAILED,
1140                                               "ersscg3", NULL);
1141                         return ZFCP_ERP_EXIT;
1142                 }
1143                 break;
1144         }
1145         return ret;
1146 }
1147
1148 static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action)
1149 {
1150         struct zfcp_adapter *adapter = erp_action->adapter;
1151
1152         adapter->erp_total_count--;
1153         if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) {
1154                 adapter->erp_low_mem_count--;
1155                 erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM;
1156         }
1157
1158         list_del(&erp_action->list);
1159         zfcp_rec_dbf_event_action("eractd1", erp_action);
1160
1161         switch (erp_action->action) {
1162         case ZFCP_ERP_ACTION_REOPEN_UNIT:
1163                 atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1164                                   &erp_action->unit->status);
1165                 break;
1166
1167         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1168         case ZFCP_ERP_ACTION_REOPEN_PORT:
1169                 atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1170                                   &erp_action->port->status);
1171                 break;
1172
1173         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1174                 atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1175                                   &erp_action->adapter->status);
1176                 break;
1177         }
1178 }
1179
1180 static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
1181 {
1182         struct zfcp_adapter *adapter = act->adapter;
1183         struct zfcp_port *port = act->port;
1184         struct zfcp_unit *unit = act->unit;
1185
1186         switch (act->action) {
1187         case ZFCP_ERP_ACTION_REOPEN_UNIT:
1188                 if ((result == ZFCP_ERP_SUCCEEDED) && !unit->device) {
1189                         zfcp_unit_get(unit);
1190                         if (scsi_queue_work(unit->port->adapter->scsi_host,
1191                                             &unit->scsi_work) <= 0)
1192                                 zfcp_unit_put(unit);
1193                 }
1194                 zfcp_unit_put(unit);
1195                 break;
1196
1197         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1198         case ZFCP_ERP_ACTION_REOPEN_PORT:
1199                 if (result == ZFCP_ERP_SUCCEEDED)
1200                         zfcp_scsi_schedule_rport_register(port);
1201                 zfcp_port_put(port);
1202                 break;
1203
1204         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1205                 if (result == ZFCP_ERP_SUCCEEDED) {
1206                         register_service_level(&adapter->service_level);
1207                         schedule_work(&adapter->scan_work);
1208                 } else
1209                         unregister_service_level(&adapter->service_level);
1210                 zfcp_adapter_put(adapter);
1211                 break;
1212         }
1213 }
1214
1215 static int zfcp_erp_strategy_do_action(struct zfcp_erp_action *erp_action)
1216 {
1217         switch (erp_action->action) {
1218         case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1219                 return zfcp_erp_adapter_strategy(erp_action);
1220         case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1221                 return zfcp_erp_port_forced_strategy(erp_action);
1222         case ZFCP_ERP_ACTION_REOPEN_PORT:
1223                 return zfcp_erp_port_strategy(erp_action);
1224         case ZFCP_ERP_ACTION_REOPEN_UNIT:
1225                 return zfcp_erp_unit_strategy(erp_action);
1226         }
1227         return ZFCP_ERP_FAILED;
1228 }
1229
1230 static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
1231 {
1232         int retval;
1233         struct zfcp_adapter *adapter = erp_action->adapter;
1234         unsigned long flags;
1235
1236         read_lock_irqsave(&zfcp_data.config_lock, flags);
1237         write_lock(&adapter->erp_lock);
1238
1239         zfcp_erp_strategy_check_fsfreq(erp_action);
1240
1241         if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED) {
1242                 zfcp_erp_action_dequeue(erp_action);
1243                 retval = ZFCP_ERP_DISMISSED;
1244                 goto unlock;
1245         }
1246
1247         zfcp_erp_action_to_running(erp_action);
1248
1249         /* no lock to allow for blocking operations */
1250         write_unlock(&adapter->erp_lock);
1251         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
1252         retval = zfcp_erp_strategy_do_action(erp_action);
1253         read_lock_irqsave(&zfcp_data.config_lock, flags);
1254         write_lock(&adapter->erp_lock);
1255
1256         if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED)
1257                 retval = ZFCP_ERP_CONTINUES;
1258
1259         switch (retval) {
1260         case ZFCP_ERP_NOMEM:
1261                 if (!(erp_action->status & ZFCP_STATUS_ERP_LOWMEM)) {
1262                         ++adapter->erp_low_mem_count;
1263                         erp_action->status |= ZFCP_STATUS_ERP_LOWMEM;
1264                 }
1265                 if (adapter->erp_total_count == adapter->erp_low_mem_count)
1266                         _zfcp_erp_adapter_reopen(adapter, 0, "erstgy1", NULL);
1267                 else {
1268                         zfcp_erp_strategy_memwait(erp_action);
1269                         retval = ZFCP_ERP_CONTINUES;
1270                 }
1271                 goto unlock;
1272
1273         case ZFCP_ERP_CONTINUES:
1274                 if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) {
1275                         --adapter->erp_low_mem_count;
1276                         erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM;
1277                 }
1278                 goto unlock;
1279         }
1280
1281         retval = zfcp_erp_strategy_check_target(erp_action, retval);
1282         zfcp_erp_action_dequeue(erp_action);
1283         retval = zfcp_erp_strategy_statechange(erp_action, retval);
1284         if (retval == ZFCP_ERP_EXIT)
1285                 goto unlock;
1286         zfcp_erp_strategy_followup_actions(erp_action);
1287
1288  unlock:
1289         write_unlock(&adapter->erp_lock);
1290         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
1291
1292         if (retval != ZFCP_ERP_CONTINUES)
1293                 zfcp_erp_action_cleanup(erp_action, retval);
1294
1295         return retval;
1296 }
1297
1298 static int zfcp_erp_thread(void *data)
1299 {
1300         struct zfcp_adapter *adapter = (struct zfcp_adapter *) data;
1301         struct list_head *next;
1302         struct zfcp_erp_action *act;
1303         unsigned long flags;
1304         int ignore;
1305
1306         daemonize("zfcperp%s", dev_name(&adapter->ccw_device->dev));
1307         /* Block all signals */
1308         siginitsetinv(&current->blocked, 0);
1309         atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status);
1310         wake_up(&adapter->erp_thread_wqh);
1311
1312         while (!(atomic_read(&adapter->status) &
1313                  ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL)) {
1314
1315                 zfcp_rec_dbf_event_thread_lock("erthrd1", adapter);
1316                 ignore = down_interruptible(&adapter->erp_ready_sem);
1317                 zfcp_rec_dbf_event_thread_lock("erthrd2", adapter);
1318
1319                 write_lock_irqsave(&adapter->erp_lock, flags);
1320                 next = adapter->erp_ready_head.next;
1321                 write_unlock_irqrestore(&adapter->erp_lock, flags);
1322
1323                 if (next != &adapter->erp_ready_head) {
1324                         act = list_entry(next, struct zfcp_erp_action, list);
1325
1326                         /* there is more to come after dismission, no notify */
1327                         if (zfcp_erp_strategy(act) != ZFCP_ERP_DISMISSED)
1328                                 zfcp_erp_wakeup(adapter);
1329                 }
1330         }
1331
1332         atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status);
1333         wake_up(&adapter->erp_thread_wqh);
1334
1335         return 0;
1336 }
1337
1338 /**
1339  * zfcp_erp_thread_setup - Start ERP thread for adapter
1340  * @adapter: Adapter to start the ERP thread for
1341  *
1342  * Returns 0 on success or error code from kernel_thread()
1343  */
1344 int zfcp_erp_thread_setup(struct zfcp_adapter *adapter)
1345 {
1346         int retval;
1347
1348         atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status);
1349         retval = kernel_thread(zfcp_erp_thread, adapter, SIGCHLD);
1350         if (retval < 0) {
1351                 dev_err(&adapter->ccw_device->dev,
1352                         "Creating an ERP thread for the FCP device failed.\n");
1353                 return retval;
1354         }
1355         wait_event(adapter->erp_thread_wqh,
1356                    atomic_read(&adapter->status) &
1357                         ZFCP_STATUS_ADAPTER_ERP_THREAD_UP);
1358         return 0;
1359 }
1360
1361 /**
1362  * zfcp_erp_thread_kill - Stop ERP thread.
1363  * @adapter: Adapter where the ERP thread should be stopped.
1364  *
1365  * The caller of this routine ensures that the specified adapter has
1366  * been shut down and that this operation has been completed. Thus,
1367  * there are no pending erp_actions which would need to be handled
1368  * here.
1369  */
1370 void zfcp_erp_thread_kill(struct zfcp_adapter *adapter)
1371 {
1372         atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL, &adapter->status);
1373         up(&adapter->erp_ready_sem);
1374         zfcp_rec_dbf_event_thread_lock("erthrk1", adapter);
1375
1376         wait_event(adapter->erp_thread_wqh,
1377                    !(atomic_read(&adapter->status) &
1378                                 ZFCP_STATUS_ADAPTER_ERP_THREAD_UP));
1379
1380         atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL,
1381                           &adapter->status);
1382 }
1383
1384 /**
1385  * zfcp_erp_adapter_failed - Set adapter status to failed.
1386  * @adapter: Failed adapter.
1387  * @id: Event id for debug trace.
1388  * @ref: Reference for debug trace.
1389  */
1390 void zfcp_erp_adapter_failed(struct zfcp_adapter *adapter, char *id, void *ref)
1391 {
1392         zfcp_erp_modify_adapter_status(adapter, id, ref,
1393                                        ZFCP_STATUS_COMMON_ERP_FAILED, ZFCP_SET);
1394 }
1395
1396 /**
1397  * zfcp_erp_port_failed - Set port status to failed.
1398  * @port: Failed port.
1399  * @id: Event id for debug trace.
1400  * @ref: Reference for debug trace.
1401  */
1402 void zfcp_erp_port_failed(struct zfcp_port *port, char *id, void *ref)
1403 {
1404         zfcp_erp_modify_port_status(port, id, ref,
1405                                     ZFCP_STATUS_COMMON_ERP_FAILED, ZFCP_SET);
1406 }
1407
1408 /**
1409  * zfcp_erp_unit_failed - Set unit status to failed.
1410  * @unit: Failed unit.
1411  * @id: Event id for debug trace.
1412  * @ref: Reference for debug trace.
1413  */
1414 void zfcp_erp_unit_failed(struct zfcp_unit *unit, char *id, void *ref)
1415 {
1416         zfcp_erp_modify_unit_status(unit, id, ref,
1417                                     ZFCP_STATUS_COMMON_ERP_FAILED, ZFCP_SET);
1418 }
1419
1420 /**
1421  * zfcp_erp_wait - wait for completion of error recovery on an adapter
1422  * @adapter: adapter for which to wait for completion of its error recovery
1423  */
1424 void zfcp_erp_wait(struct zfcp_adapter *adapter)
1425 {
1426         wait_event(adapter->erp_done_wqh,
1427                    !(atomic_read(&adapter->status) &
1428                         ZFCP_STATUS_ADAPTER_ERP_PENDING));
1429 }
1430
1431 /**
1432  * zfcp_erp_modify_adapter_status - change adapter status bits
1433  * @adapter: adapter to change the status
1434  * @id: id for the debug trace
1435  * @ref: reference for the debug trace
1436  * @mask: status bits to change
1437  * @set_or_clear: ZFCP_SET or ZFCP_CLEAR
1438  *
1439  * Changes in common status bits are propagated to attached ports and units.
1440  */
1441 void zfcp_erp_modify_adapter_status(struct zfcp_adapter *adapter, char *id,
1442                                     void *ref, u32 mask, int set_or_clear)
1443 {
1444         struct zfcp_port *port;
1445         u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1446
1447         if (set_or_clear == ZFCP_SET) {
1448                 if (status_change_set(mask, &adapter->status))
1449                         zfcp_rec_dbf_event_adapter(id, ref, adapter);
1450                 atomic_set_mask(mask, &adapter->status);
1451         } else {
1452                 if (status_change_clear(mask, &adapter->status))
1453                         zfcp_rec_dbf_event_adapter(id, ref, adapter);
1454                 atomic_clear_mask(mask, &adapter->status);
1455                 if (mask & ZFCP_STATUS_COMMON_ERP_FAILED)
1456                         atomic_set(&adapter->erp_counter, 0);
1457         }
1458
1459         if (common_mask)
1460                 list_for_each_entry(port, &adapter->port_list_head, list)
1461                         zfcp_erp_modify_port_status(port, id, ref, common_mask,
1462                                                     set_or_clear);
1463 }
1464
1465 /**
1466  * zfcp_erp_modify_port_status - change port status bits
1467  * @port: port to change the status bits
1468  * @id: id for the debug trace
1469  * @ref: reference for the debug trace
1470  * @mask: status bits to change
1471  * @set_or_clear: ZFCP_SET or ZFCP_CLEAR
1472  *
1473  * Changes in common status bits are propagated to attached units.
1474  */
1475 void zfcp_erp_modify_port_status(struct zfcp_port *port, char *id, void *ref,
1476                                  u32 mask, int set_or_clear)
1477 {
1478         struct zfcp_unit *unit;
1479         u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1480
1481         if (set_or_clear == ZFCP_SET) {
1482                 if (status_change_set(mask, &port->status))
1483                         zfcp_rec_dbf_event_port(id, ref, port);
1484                 atomic_set_mask(mask, &port->status);
1485         } else {
1486                 if (status_change_clear(mask, &port->status))
1487                         zfcp_rec_dbf_event_port(id, ref, port);
1488                 atomic_clear_mask(mask, &port->status);
1489                 if (mask & ZFCP_STATUS_COMMON_ERP_FAILED)
1490                         atomic_set(&port->erp_counter, 0);
1491         }
1492
1493         if (common_mask)
1494                 list_for_each_entry(unit, &port->unit_list_head, list)
1495                         zfcp_erp_modify_unit_status(unit, id, ref, common_mask,
1496                                                     set_or_clear);
1497 }
1498
1499 /**
1500  * zfcp_erp_modify_unit_status - change unit status bits
1501  * @unit: unit to change the status bits
1502  * @id: id for the debug trace
1503  * @ref: reference for the debug trace
1504  * @mask: status bits to change
1505  * @set_or_clear: ZFCP_SET or ZFCP_CLEAR
1506  */
1507 void zfcp_erp_modify_unit_status(struct zfcp_unit *unit, char *id, void *ref,
1508                                  u32 mask, int set_or_clear)
1509 {
1510         if (set_or_clear == ZFCP_SET) {
1511                 if (status_change_set(mask, &unit->status))
1512                         zfcp_rec_dbf_event_unit(id, ref, unit);
1513                 atomic_set_mask(mask, &unit->status);
1514         } else {
1515                 if (status_change_clear(mask, &unit->status))
1516                         zfcp_rec_dbf_event_unit(id, ref, unit);
1517                 atomic_clear_mask(mask, &unit->status);
1518                 if (mask & ZFCP_STATUS_COMMON_ERP_FAILED) {
1519                         atomic_set(&unit->erp_counter, 0);
1520                 }
1521         }
1522 }
1523
1524 /**
1525  * zfcp_erp_port_boxed - Mark port as "boxed" and start ERP
1526  * @port: The "boxed" port.
1527  * @id: The debug trace id.
1528  * @id: Reference for the debug trace.
1529  */
1530 void zfcp_erp_port_boxed(struct zfcp_port *port, char *id, void *ref)
1531 {
1532         unsigned long flags;
1533
1534         read_lock_irqsave(&zfcp_data.config_lock, flags);
1535         zfcp_erp_modify_port_status(port, id, ref,
1536                                     ZFCP_STATUS_COMMON_ACCESS_BOXED, ZFCP_SET);
1537         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
1538         zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED, id, ref);
1539 }
1540
1541 /**
1542  * zfcp_erp_unit_boxed - Mark unit as "boxed" and start ERP
1543  * @port: The "boxed" unit.
1544  * @id: The debug trace id.
1545  * @id: Reference for the debug trace.
1546  */
1547 void zfcp_erp_unit_boxed(struct zfcp_unit *unit, char *id, void *ref)
1548 {
1549         zfcp_erp_modify_unit_status(unit, id, ref,
1550                                     ZFCP_STATUS_COMMON_ACCESS_BOXED, ZFCP_SET);
1551         zfcp_erp_unit_reopen(unit, ZFCP_STATUS_COMMON_ERP_FAILED, id, ref);
1552 }
1553
1554 /**
1555  * zfcp_erp_port_access_denied - Adapter denied access to port.
1556  * @port: port where access has been denied
1557  * @id: id for debug trace
1558  * @ref: reference for debug trace
1559  *
1560  * Since the adapter has denied access, stop using the port and the
1561  * attached units.
1562  */
1563 void zfcp_erp_port_access_denied(struct zfcp_port *port, char *id, void *ref)
1564 {
1565         unsigned long flags;
1566
1567         read_lock_irqsave(&zfcp_data.config_lock, flags);
1568         zfcp_erp_modify_port_status(port, id, ref,
1569                                     ZFCP_STATUS_COMMON_ERP_FAILED |
1570                                     ZFCP_STATUS_COMMON_ACCESS_DENIED, ZFCP_SET);
1571         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
1572 }
1573
1574 /**
1575  * zfcp_erp_unit_access_denied - Adapter denied access to unit.
1576  * @unit: unit where access has been denied
1577  * @id: id for debug trace
1578  * @ref: reference for debug trace
1579  *
1580  * Since the adapter has denied access, stop using the unit.
1581  */
1582 void zfcp_erp_unit_access_denied(struct zfcp_unit *unit, char *id, void *ref)
1583 {
1584         zfcp_erp_modify_unit_status(unit, id, ref,
1585                                     ZFCP_STATUS_COMMON_ERP_FAILED |
1586                                     ZFCP_STATUS_COMMON_ACCESS_DENIED, ZFCP_SET);
1587 }
1588
1589 static void zfcp_erp_unit_access_changed(struct zfcp_unit *unit, char *id,
1590                                          void *ref)
1591 {
1592         int status = atomic_read(&unit->status);
1593         if (!(status & (ZFCP_STATUS_COMMON_ACCESS_DENIED |
1594                         ZFCP_STATUS_COMMON_ACCESS_BOXED)))
1595                 return;
1596
1597         zfcp_erp_unit_reopen(unit, ZFCP_STATUS_COMMON_ERP_FAILED, id, ref);
1598 }
1599
1600 static void zfcp_erp_port_access_changed(struct zfcp_port *port, char *id,
1601                                          void *ref)
1602 {
1603         struct zfcp_unit *unit;
1604         int status = atomic_read(&port->status);
1605
1606         if (!(status & (ZFCP_STATUS_COMMON_ACCESS_DENIED |
1607                         ZFCP_STATUS_COMMON_ACCESS_BOXED))) {
1608                 list_for_each_entry(unit, &port->unit_list_head, list)
1609                                     zfcp_erp_unit_access_changed(unit, id, ref);
1610                 return;
1611         }
1612
1613         zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED, id, ref);
1614 }
1615
1616 /**
1617  * zfcp_erp_adapter_access_changed - Process change in adapter ACT
1618  * @adapter: Adapter where the Access Control Table (ACT) changed
1619  * @id: Id for debug trace
1620  * @ref: Reference for debug trace
1621  */
1622 void zfcp_erp_adapter_access_changed(struct zfcp_adapter *adapter, char *id,
1623                                      void *ref)
1624 {
1625         struct zfcp_port *port;
1626         unsigned long flags;
1627
1628         if (adapter->connection_features & FSF_FEATURE_NPIV_MODE)
1629                 return;
1630
1631         read_lock_irqsave(&zfcp_data.config_lock, flags);
1632         list_for_each_entry(port, &adapter->port_list_head, list)
1633                 zfcp_erp_port_access_changed(port, id, ref);
1634         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
1635 }