1/*
2 * zfcp device driver
3 *
4 * Error Recovery Procedures (ERP).
5 *
6 * Copyright IBM Corp. 2002, 2010
7 */
8
9#define KMSG_COMPONENT "zfcp"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/kthread.h>
13#include "zfcp_ext.h"
14#include "zfcp_reqlist.h"
15
16#define ZFCP_MAX_ERPS                   3
17
18enum zfcp_erp_act_flags {
19	ZFCP_STATUS_ERP_TIMEDOUT	= 0x10000000,
20	ZFCP_STATUS_ERP_CLOSE_ONLY	= 0x01000000,
21	ZFCP_STATUS_ERP_DISMISSING	= 0x00100000,
22	ZFCP_STATUS_ERP_DISMISSED	= 0x00200000,
23	ZFCP_STATUS_ERP_LOWMEM		= 0x00400000,
24	ZFCP_STATUS_ERP_NO_REF		= 0x00800000,
25};
26
27enum zfcp_erp_steps {
28	ZFCP_ERP_STEP_UNINITIALIZED	= 0x0000,
29	ZFCP_ERP_STEP_FSF_XCONFIG	= 0x0001,
30	ZFCP_ERP_STEP_PHYS_PORT_CLOSING	= 0x0010,
31	ZFCP_ERP_STEP_PORT_CLOSING	= 0x0100,
32	ZFCP_ERP_STEP_PORT_OPENING	= 0x0800,
33	ZFCP_ERP_STEP_LUN_CLOSING	= 0x1000,
34	ZFCP_ERP_STEP_LUN_OPENING	= 0x2000,
35};
36
37enum zfcp_erp_act_type {
38	ZFCP_ERP_ACTION_REOPEN_LUN         = 1,
39	ZFCP_ERP_ACTION_REOPEN_PORT	   = 2,
40	ZFCP_ERP_ACTION_REOPEN_PORT_FORCED = 3,
41	ZFCP_ERP_ACTION_REOPEN_ADAPTER     = 4,
42};
43
44enum zfcp_erp_act_state {
45	ZFCP_ERP_ACTION_RUNNING = 1,
46	ZFCP_ERP_ACTION_READY   = 2,
47};
48
49enum zfcp_erp_act_result {
50	ZFCP_ERP_SUCCEEDED = 0,
51	ZFCP_ERP_FAILED    = 1,
52	ZFCP_ERP_CONTINUES = 2,
53	ZFCP_ERP_EXIT      = 3,
54	ZFCP_ERP_DISMISSED = 4,
55	ZFCP_ERP_NOMEM     = 5,
56};
57
58static void zfcp_erp_adapter_block(struct zfcp_adapter *adapter, int mask)
59{
60	zfcp_erp_clear_adapter_status(adapter,
61				       ZFCP_STATUS_COMMON_UNBLOCKED | mask);
62}
63
64static int zfcp_erp_action_exists(struct zfcp_erp_action *act)
65{
66	struct zfcp_erp_action *curr_act;
67
68	list_for_each_entry(curr_act, &act->adapter->erp_running_head, list)
69		if (act == curr_act)
70			return ZFCP_ERP_ACTION_RUNNING;
71	return 0;
72}
73
74static void zfcp_erp_action_ready(struct zfcp_erp_action *act)
75{
76	struct zfcp_adapter *adapter = act->adapter;
77
78	list_move(&act->list, &act->adapter->erp_ready_head);
79	zfcp_dbf_rec_run("erardy1", act);
80	wake_up(&adapter->erp_ready_wq);
81	zfcp_dbf_rec_run("erardy2", act);
82}
83
84static void zfcp_erp_action_dismiss(struct zfcp_erp_action *act)
85{
86	act->status |= ZFCP_STATUS_ERP_DISMISSED;
87	if (zfcp_erp_action_exists(act) == ZFCP_ERP_ACTION_RUNNING)
88		zfcp_erp_action_ready(act);
89}
90
91static void zfcp_erp_action_dismiss_lun(struct scsi_device *sdev)
92{
93	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
94
95	if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
96		zfcp_erp_action_dismiss(&zfcp_sdev->erp_action);
97}
98
99static void zfcp_erp_action_dismiss_port(struct zfcp_port *port)
100{
101	struct scsi_device *sdev;
102
103	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
104		zfcp_erp_action_dismiss(&port->erp_action);
105	else {
106		spin_lock(port->adapter->scsi_host->host_lock);
107		__shost_for_each_device(sdev, port->adapter->scsi_host)
108			if (sdev_to_zfcp(sdev)->port == port)
109				zfcp_erp_action_dismiss_lun(sdev);
110		spin_unlock(port->adapter->scsi_host->host_lock);
111	}
112}
113
114static void zfcp_erp_action_dismiss_adapter(struct zfcp_adapter *adapter)
115{
116	struct zfcp_port *port;
117
118	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_INUSE)
119		zfcp_erp_action_dismiss(&adapter->erp_action);
120	else {
121		read_lock(&adapter->port_list_lock);
122		list_for_each_entry(port, &adapter->port_list, list)
123		    zfcp_erp_action_dismiss_port(port);
124		read_unlock(&adapter->port_list_lock);
125	}
126}
127
128static int zfcp_erp_required_act(int want, struct zfcp_adapter *adapter,
129				 struct zfcp_port *port,
130				 struct scsi_device *sdev)
131{
132	int need = want;
133	int l_status, p_status, a_status;
134	struct zfcp_scsi_dev *zfcp_sdev;
135
136	switch (want) {
137	case ZFCP_ERP_ACTION_REOPEN_LUN:
138		zfcp_sdev = sdev_to_zfcp(sdev);
139		l_status = atomic_read(&zfcp_sdev->status);
140		if (l_status & ZFCP_STATUS_COMMON_ERP_INUSE)
141			return 0;
142		p_status = atomic_read(&port->status);
143		if (!(p_status & ZFCP_STATUS_COMMON_RUNNING) ||
144		      p_status & ZFCP_STATUS_COMMON_ERP_FAILED)
145			return 0;
146		if (!(p_status & ZFCP_STATUS_COMMON_UNBLOCKED))
147			need = ZFCP_ERP_ACTION_REOPEN_PORT;
148		/* fall through */
149	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
150		p_status = atomic_read(&port->status);
151		if (!(p_status & ZFCP_STATUS_COMMON_OPEN))
152			need = ZFCP_ERP_ACTION_REOPEN_PORT;
153		/* fall through */
154	case ZFCP_ERP_ACTION_REOPEN_PORT:
155		p_status = atomic_read(&port->status);
156		if (p_status & ZFCP_STATUS_COMMON_ERP_INUSE)
157			return 0;
158		a_status = atomic_read(&adapter->status);
159		if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) ||
160		      a_status & ZFCP_STATUS_COMMON_ERP_FAILED)
161			return 0;
162		if (p_status & ZFCP_STATUS_COMMON_NOESC)
163			return need;
164		if (!(a_status & ZFCP_STATUS_COMMON_UNBLOCKED))
165			need = ZFCP_ERP_ACTION_REOPEN_ADAPTER;
166		/* fall through */
167	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
168		a_status = atomic_read(&adapter->status);
169		if (a_status & ZFCP_STATUS_COMMON_ERP_INUSE)
170			return 0;
171		if (!(a_status & ZFCP_STATUS_COMMON_RUNNING) &&
172		    !(a_status & ZFCP_STATUS_COMMON_OPEN))
173			return 0; /* shutdown requested for closed adapter */
174	}
175
176	return need;
177}
178
179static struct zfcp_erp_action *zfcp_erp_setup_act(int need, u32 act_status,
180						  struct zfcp_adapter *adapter,
181						  struct zfcp_port *port,
182						  struct scsi_device *sdev)
183{
184	struct zfcp_erp_action *erp_action;
185	struct zfcp_scsi_dev *zfcp_sdev;
186
187	switch (need) {
188	case ZFCP_ERP_ACTION_REOPEN_LUN:
189		zfcp_sdev = sdev_to_zfcp(sdev);
190		if (!(act_status & ZFCP_STATUS_ERP_NO_REF))
191			if (scsi_device_get(sdev))
192				return NULL;
193		atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
194				&zfcp_sdev->status);
195		erp_action = &zfcp_sdev->erp_action;
196		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
197		erp_action->port = port;
198		erp_action->sdev = sdev;
199		if (!(atomic_read(&zfcp_sdev->status) &
200		      ZFCP_STATUS_COMMON_RUNNING))
201			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
202		break;
203
204	case ZFCP_ERP_ACTION_REOPEN_PORT:
205	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
206		if (!get_device(&port->dev))
207			return NULL;
208		zfcp_erp_action_dismiss_port(port);
209		atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE, &port->status);
210		erp_action = &port->erp_action;
211		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
212		erp_action->port = port;
213		if (!(atomic_read(&port->status) & ZFCP_STATUS_COMMON_RUNNING))
214			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
215		break;
216
217	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
218		kref_get(&adapter->ref);
219		zfcp_erp_action_dismiss_adapter(adapter);
220		atomic_set_mask(ZFCP_STATUS_COMMON_ERP_INUSE, &adapter->status);
221		erp_action = &adapter->erp_action;
222		memset(erp_action, 0, sizeof(struct zfcp_erp_action));
223		if (!(atomic_read(&adapter->status) &
224		      ZFCP_STATUS_COMMON_RUNNING))
225			act_status |= ZFCP_STATUS_ERP_CLOSE_ONLY;
226		break;
227
228	default:
229		return NULL;
230	}
231
232	erp_action->adapter = adapter;
233	erp_action->action = need;
234	erp_action->status = act_status;
235
236	return erp_action;
237}
238
239static int zfcp_erp_action_enqueue(int want, struct zfcp_adapter *adapter,
240				   struct zfcp_port *port,
241				   struct scsi_device *sdev,
242				   char *id, u32 act_status)
243{
244	int retval = 1, need;
245	struct zfcp_erp_action *act;
246
247	if (!adapter->erp_thread)
248		return -EIO;
249
250	need = zfcp_erp_required_act(want, adapter, port, sdev);
251	if (!need)
252		goto out;
253
254	act = zfcp_erp_setup_act(need, act_status, adapter, port, sdev);
255	if (!act)
256		goto out;
257	atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_PENDING, &adapter->status);
258	++adapter->erp_total_count;
259	list_add_tail(&act->list, &adapter->erp_ready_head);
260	wake_up(&adapter->erp_ready_wq);
261	retval = 0;
262 out:
263	zfcp_dbf_rec_trig(id, adapter, port, sdev, want, need);
264	return retval;
265}
266
267static int _zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter,
268				    int clear_mask, char *id)
269{
270	zfcp_erp_adapter_block(adapter, clear_mask);
271	zfcp_scsi_schedule_rports_block(adapter);
272
273	/* ensure propagation of failed status to new devices */
274	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
275		zfcp_erp_set_adapter_status(adapter,
276					    ZFCP_STATUS_COMMON_ERP_FAILED);
277		return -EIO;
278	}
279	return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER,
280				       adapter, NULL, NULL, id, 0);
281}
282
283/**
284 * zfcp_erp_adapter_reopen - Reopen adapter.
285 * @adapter: Adapter to reopen.
286 * @clear: Status flags to clear.
287 * @id: Id for debug trace event.
288 */
289void zfcp_erp_adapter_reopen(struct zfcp_adapter *adapter, int clear, char *id)
290{
291	unsigned long flags;
292
293	zfcp_erp_adapter_block(adapter, clear);
294	zfcp_scsi_schedule_rports_block(adapter);
295
296	write_lock_irqsave(&adapter->erp_lock, flags);
297	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
298		zfcp_erp_set_adapter_status(adapter,
299					    ZFCP_STATUS_COMMON_ERP_FAILED);
300	else
301		zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_ADAPTER, adapter,
302					NULL, NULL, id, 0);
303	write_unlock_irqrestore(&adapter->erp_lock, flags);
304}
305
306/**
307 * zfcp_erp_adapter_shutdown - Shutdown adapter.
308 * @adapter: Adapter to shut down.
309 * @clear: Status flags to clear.
310 * @id: Id for debug trace event.
311 */
312void zfcp_erp_adapter_shutdown(struct zfcp_adapter *adapter, int clear,
313			       char *id)
314{
315	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
316	zfcp_erp_adapter_reopen(adapter, clear | flags, id);
317}
318
319/**
320 * zfcp_erp_port_shutdown - Shutdown port
321 * @port: Port to shut down.
322 * @clear: Status flags to clear.
323 * @id: Id for debug trace event.
324 */
325void zfcp_erp_port_shutdown(struct zfcp_port *port, int clear, char *id)
326{
327	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
328	zfcp_erp_port_reopen(port, clear | flags, id);
329}
330
331static void zfcp_erp_port_block(struct zfcp_port *port, int clear)
332{
333	zfcp_erp_clear_port_status(port,
334				    ZFCP_STATUS_COMMON_UNBLOCKED | clear);
335}
336
337static void _zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear,
338					 char *id)
339{
340	zfcp_erp_port_block(port, clear);
341	zfcp_scsi_schedule_rport_block(port);
342
343	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
344		return;
345
346	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
347				port->adapter, port, NULL, id, 0);
348}
349
350/**
351 * zfcp_erp_port_forced_reopen - Forced close of port and open again
352 * @port: Port to force close and to reopen.
353 * @clear: Status flags to clear.
354 * @id: Id for debug trace event.
355 */
356void zfcp_erp_port_forced_reopen(struct zfcp_port *port, int clear, char *id)
357{
358	unsigned long flags;
359	struct zfcp_adapter *adapter = port->adapter;
360
361	write_lock_irqsave(&adapter->erp_lock, flags);
362	_zfcp_erp_port_forced_reopen(port, clear, id);
363	write_unlock_irqrestore(&adapter->erp_lock, flags);
364}
365
366static int _zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id)
367{
368	zfcp_erp_port_block(port, clear);
369	zfcp_scsi_schedule_rport_block(port);
370
371	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
372		/* ensure propagation of failed status to new devices */
373		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
374		return -EIO;
375	}
376
377	return zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_PORT,
378				       port->adapter, port, NULL, id, 0);
379}
380
381/**
382 * zfcp_erp_port_reopen - trigger remote port recovery
383 * @port: port to recover
384 * @clear_mask: flags in port status to be cleared
385 * @id: Id for debug trace event.
386 *
387 * Returns 0 if recovery has been triggered, < 0 if not.
388 */
389int zfcp_erp_port_reopen(struct zfcp_port *port, int clear, char *id)
390{
391	int retval;
392	unsigned long flags;
393	struct zfcp_adapter *adapter = port->adapter;
394
395	write_lock_irqsave(&adapter->erp_lock, flags);
396	retval = _zfcp_erp_port_reopen(port, clear, id);
397	write_unlock_irqrestore(&adapter->erp_lock, flags);
398
399	return retval;
400}
401
402static void zfcp_erp_lun_block(struct scsi_device *sdev, int clear_mask)
403{
404	zfcp_erp_clear_lun_status(sdev,
405				  ZFCP_STATUS_COMMON_UNBLOCKED | clear_mask);
406}
407
408static void _zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id,
409				 u32 act_status)
410{
411	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
412	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
413
414	zfcp_erp_lun_block(sdev, clear);
415
416	if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED)
417		return;
418
419	zfcp_erp_action_enqueue(ZFCP_ERP_ACTION_REOPEN_LUN, adapter,
420				zfcp_sdev->port, sdev, id, act_status);
421}
422
423/**
424 * zfcp_erp_lun_reopen - initiate reopen of a LUN
425 * @sdev: SCSI device / LUN to be reopened
426 * @clear_mask: specifies flags in LUN status to be cleared
427 * @id: Id for debug trace event.
428 *
429 * Return: 0 on success, < 0 on error
430 */
431void zfcp_erp_lun_reopen(struct scsi_device *sdev, int clear, char *id)
432{
433	unsigned long flags;
434	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
435	struct zfcp_port *port = zfcp_sdev->port;
436	struct zfcp_adapter *adapter = port->adapter;
437
438	write_lock_irqsave(&adapter->erp_lock, flags);
439	_zfcp_erp_lun_reopen(sdev, clear, id, 0);
440	write_unlock_irqrestore(&adapter->erp_lock, flags);
441}
442
443/**
444 * zfcp_erp_lun_shutdown - Shutdown LUN
445 * @sdev: SCSI device / LUN to shut down.
446 * @clear: Status flags to clear.
447 * @id: Id for debug trace event.
448 */
449void zfcp_erp_lun_shutdown(struct scsi_device *sdev, int clear, char *id)
450{
451	int flags = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
452	zfcp_erp_lun_reopen(sdev, clear | flags, id);
453}
454
455/**
456 * zfcp_erp_lun_shutdown_wait - Shutdown LUN and wait for erp completion
457 * @sdev: SCSI device / LUN to shut down.
458 * @id: Id for debug trace event.
459 *
460 * Do not acquire a reference for the LUN when creating the ERP
461 * action. It is safe, because this function waits for the ERP to
462 * complete first. This allows to shutdown the LUN, even when the SCSI
463 * device is in the state SDEV_DEL when scsi_device_get will fail.
464 */
465void zfcp_erp_lun_shutdown_wait(struct scsi_device *sdev, char *id)
466{
467	unsigned long flags;
468	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
469	struct zfcp_port *port = zfcp_sdev->port;
470	struct zfcp_adapter *adapter = port->adapter;
471	int clear = ZFCP_STATUS_COMMON_RUNNING | ZFCP_STATUS_COMMON_ERP_FAILED;
472
473	write_lock_irqsave(&adapter->erp_lock, flags);
474	_zfcp_erp_lun_reopen(sdev, clear, id, ZFCP_STATUS_ERP_NO_REF);
475	write_unlock_irqrestore(&adapter->erp_lock, flags);
476
477	zfcp_erp_wait(adapter);
478}
479
480static int status_change_set(unsigned long mask, atomic_t *status)
481{
482	return (atomic_read(status) ^ mask) & mask;
483}
484
485static void zfcp_erp_adapter_unblock(struct zfcp_adapter *adapter)
486{
487	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status))
488		zfcp_dbf_rec_run("eraubl1", &adapter->erp_action);
489	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &adapter->status);
490}
491
492static void zfcp_erp_port_unblock(struct zfcp_port *port)
493{
494	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status))
495		zfcp_dbf_rec_run("erpubl1", &port->erp_action);
496	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &port->status);
497}
498
499static void zfcp_erp_lun_unblock(struct scsi_device *sdev)
500{
501	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
502
503	if (status_change_set(ZFCP_STATUS_COMMON_UNBLOCKED, &zfcp_sdev->status))
504		zfcp_dbf_rec_run("erlubl1", &sdev_to_zfcp(sdev)->erp_action);
505	atomic_set_mask(ZFCP_STATUS_COMMON_UNBLOCKED, &zfcp_sdev->status);
506}
507
508static void zfcp_erp_action_to_running(struct zfcp_erp_action *erp_action)
509{
510	list_move(&erp_action->list, &erp_action->adapter->erp_running_head);
511	zfcp_dbf_rec_run("erator1", erp_action);
512}
513
514static void zfcp_erp_strategy_check_fsfreq(struct zfcp_erp_action *act)
515{
516	struct zfcp_adapter *adapter = act->adapter;
517	struct zfcp_fsf_req *req;
518
519	if (!act->fsf_req_id)
520		return;
521
522	spin_lock(&adapter->req_list->lock);
523	req = _zfcp_reqlist_find(adapter->req_list, act->fsf_req_id);
524	if (req && req->erp_action == act) {
525		if (act->status & (ZFCP_STATUS_ERP_DISMISSED |
526				   ZFCP_STATUS_ERP_TIMEDOUT)) {
527			req->status |= ZFCP_STATUS_FSFREQ_DISMISSED;
528			zfcp_dbf_rec_run("erscf_1", act);
529			req->erp_action = NULL;
530		}
531		if (act->status & ZFCP_STATUS_ERP_TIMEDOUT)
532			zfcp_dbf_rec_run("erscf_2", act);
533		if (req->status & ZFCP_STATUS_FSFREQ_DISMISSED)
534			act->fsf_req_id = 0;
535	} else
536		act->fsf_req_id = 0;
537	spin_unlock(&adapter->req_list->lock);
538}
539
540/**
541 * zfcp_erp_notify - Trigger ERP action.
542 * @erp_action: ERP action to continue.
543 * @set_mask: ERP action status flags to set.
544 */
545void zfcp_erp_notify(struct zfcp_erp_action *erp_action, unsigned long set_mask)
546{
547	struct zfcp_adapter *adapter = erp_action->adapter;
548	unsigned long flags;
549
550	write_lock_irqsave(&adapter->erp_lock, flags);
551	if (zfcp_erp_action_exists(erp_action) == ZFCP_ERP_ACTION_RUNNING) {
552		erp_action->status |= set_mask;
553		zfcp_erp_action_ready(erp_action);
554	}
555	write_unlock_irqrestore(&adapter->erp_lock, flags);
556}
557
558/**
559 * zfcp_erp_timeout_handler - Trigger ERP action from timed out ERP request
560 * @data: ERP action (from timer data)
561 */
562void zfcp_erp_timeout_handler(unsigned long data)
563{
564	struct zfcp_erp_action *act = (struct zfcp_erp_action *) data;
565	zfcp_erp_notify(act, ZFCP_STATUS_ERP_TIMEDOUT);
566}
567
568static void zfcp_erp_memwait_handler(unsigned long data)
569{
570	zfcp_erp_notify((struct zfcp_erp_action *)data, 0);
571}
572
573static void zfcp_erp_strategy_memwait(struct zfcp_erp_action *erp_action)
574{
575	init_timer(&erp_action->timer);
576	erp_action->timer.function = zfcp_erp_memwait_handler;
577	erp_action->timer.data = (unsigned long) erp_action;
578	erp_action->timer.expires = jiffies + HZ;
579	add_timer(&erp_action->timer);
580}
581
582static void _zfcp_erp_port_reopen_all(struct zfcp_adapter *adapter,
583				      int clear, char *id)
584{
585	struct zfcp_port *port;
586
587	read_lock(&adapter->port_list_lock);
588	list_for_each_entry(port, &adapter->port_list, list)
589		_zfcp_erp_port_reopen(port, clear, id);
590	read_unlock(&adapter->port_list_lock);
591}
592
593static void _zfcp_erp_lun_reopen_all(struct zfcp_port *port, int clear,
594				     char *id)
595{
596	struct scsi_device *sdev;
597
598	spin_lock(port->adapter->scsi_host->host_lock);
599	__shost_for_each_device(sdev, port->adapter->scsi_host)
600		if (sdev_to_zfcp(sdev)->port == port)
601			_zfcp_erp_lun_reopen(sdev, clear, id, 0);
602	spin_unlock(port->adapter->scsi_host->host_lock);
603}
604
605static void zfcp_erp_strategy_followup_failed(struct zfcp_erp_action *act)
606{
607	switch (act->action) {
608	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
609		_zfcp_erp_adapter_reopen(act->adapter, 0, "ersff_1");
610		break;
611	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
612		_zfcp_erp_port_forced_reopen(act->port, 0, "ersff_2");
613		break;
614	case ZFCP_ERP_ACTION_REOPEN_PORT:
615		_zfcp_erp_port_reopen(act->port, 0, "ersff_3");
616		break;
617	case ZFCP_ERP_ACTION_REOPEN_LUN:
618		_zfcp_erp_lun_reopen(act->sdev, 0, "ersff_4", 0);
619		break;
620	}
621}
622
623static void zfcp_erp_strategy_followup_success(struct zfcp_erp_action *act)
624{
625	switch (act->action) {
626	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
627		_zfcp_erp_port_reopen_all(act->adapter, 0, "ersfs_1");
628		break;
629	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
630		_zfcp_erp_port_reopen(act->port, 0, "ersfs_2");
631		break;
632	case ZFCP_ERP_ACTION_REOPEN_PORT:
633		_zfcp_erp_lun_reopen_all(act->port, 0, "ersfs_3");
634		break;
635	}
636}
637
638static void zfcp_erp_wakeup(struct zfcp_adapter *adapter)
639{
640	unsigned long flags;
641
642	read_lock_irqsave(&adapter->erp_lock, flags);
643	if (list_empty(&adapter->erp_ready_head) &&
644	    list_empty(&adapter->erp_running_head)) {
645			atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_PENDING,
646					  &adapter->status);
647			wake_up(&adapter->erp_done_wqh);
648	}
649	read_unlock_irqrestore(&adapter->erp_lock, flags);
650}
651
652static void zfcp_erp_enqueue_ptp_port(struct zfcp_adapter *adapter)
653{
654	struct zfcp_port *port;
655	port = zfcp_port_enqueue(adapter, adapter->peer_wwpn, 0,
656				 adapter->peer_d_id);
657	if (IS_ERR(port)) /* error or port already attached */
658		return;
659	_zfcp_erp_port_reopen(port, 0, "ereptp1");
660}
661
662static int zfcp_erp_adapter_strat_fsf_xconf(struct zfcp_erp_action *erp_action)
663{
664	int retries;
665	int sleep = 1;
666	struct zfcp_adapter *adapter = erp_action->adapter;
667
668	atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK, &adapter->status);
669
670	for (retries = 7; retries; retries--) {
671		atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
672				  &adapter->status);
673		write_lock_irq(&adapter->erp_lock);
674		zfcp_erp_action_to_running(erp_action);
675		write_unlock_irq(&adapter->erp_lock);
676		if (zfcp_fsf_exchange_config_data(erp_action)) {
677			atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
678					  &adapter->status);
679			return ZFCP_ERP_FAILED;
680		}
681
682		wait_event(adapter->erp_ready_wq,
683			   !list_empty(&adapter->erp_ready_head));
684		if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT)
685			break;
686
687		if (!(atomic_read(&adapter->status) &
688		      ZFCP_STATUS_ADAPTER_HOST_CON_INIT))
689			break;
690
691		ssleep(sleep);
692		sleep *= 2;
693	}
694
695	atomic_clear_mask(ZFCP_STATUS_ADAPTER_HOST_CON_INIT,
696			  &adapter->status);
697
698	if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_XCONFIG_OK))
699		return ZFCP_ERP_FAILED;
700
701	if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
702		zfcp_erp_enqueue_ptp_port(adapter);
703
704	return ZFCP_ERP_SUCCEEDED;
705}
706
707static int zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *act)
708{
709	int ret;
710	struct zfcp_adapter *adapter = act->adapter;
711
712	write_lock_irq(&adapter->erp_lock);
713	zfcp_erp_action_to_running(act);
714	write_unlock_irq(&adapter->erp_lock);
715
716	ret = zfcp_fsf_exchange_port_data(act);
717	if (ret == -EOPNOTSUPP)
718		return ZFCP_ERP_SUCCEEDED;
719	if (ret)
720		return ZFCP_ERP_FAILED;
721
722	zfcp_dbf_rec_run("erasox1", act);
723	wait_event(adapter->erp_ready_wq,
724		   !list_empty(&adapter->erp_ready_head));
725	zfcp_dbf_rec_run("erasox2", act);
726	if (act->status & ZFCP_STATUS_ERP_TIMEDOUT)
727		return ZFCP_ERP_FAILED;
728
729	return ZFCP_ERP_SUCCEEDED;
730}
731
732static int zfcp_erp_adapter_strategy_open_fsf(struct zfcp_erp_action *act)
733{
734	if (zfcp_erp_adapter_strat_fsf_xconf(act) == ZFCP_ERP_FAILED)
735		return ZFCP_ERP_FAILED;
736
737	if (zfcp_erp_adapter_strategy_open_fsf_xport(act) == ZFCP_ERP_FAILED)
738		return ZFCP_ERP_FAILED;
739
740	if (mempool_resize(act->adapter->pool.sr_data,
741			   act->adapter->stat_read_buf_num))
742		return ZFCP_ERP_FAILED;
743
744	if (mempool_resize(act->adapter->pool.status_read_req,
745			   act->adapter->stat_read_buf_num))
746		return ZFCP_ERP_FAILED;
747
748	atomic_set(&act->adapter->stat_miss, act->adapter->stat_read_buf_num);
749	if (zfcp_status_read_refill(act->adapter))
750		return ZFCP_ERP_FAILED;
751
752	return ZFCP_ERP_SUCCEEDED;
753}
754
755static void zfcp_erp_adapter_strategy_close(struct zfcp_erp_action *act)
756{
757	struct zfcp_adapter *adapter = act->adapter;
758
759	/* close queues to ensure that buffers are not accessed by adapter */
760	zfcp_qdio_close(adapter->qdio);
761	zfcp_fsf_req_dismiss_all(adapter);
762	adapter->fsf_req_seq_no = 0;
763	zfcp_fc_wka_ports_force_offline(adapter->gs);
764	/* all ports and LUNs are closed */
765	zfcp_erp_clear_adapter_status(adapter, ZFCP_STATUS_COMMON_OPEN);
766
767	atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK |
768			  ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED, &adapter->status);
769}
770
771static int zfcp_erp_adapter_strategy_open(struct zfcp_erp_action *act)
772{
773	struct zfcp_adapter *adapter = act->adapter;
774
775	if (zfcp_qdio_open(adapter->qdio)) {
776		atomic_clear_mask(ZFCP_STATUS_ADAPTER_XCONFIG_OK |
777				  ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED,
778				  &adapter->status);
779		return ZFCP_ERP_FAILED;
780	}
781
782	if (zfcp_erp_adapter_strategy_open_fsf(act)) {
783		zfcp_erp_adapter_strategy_close(act);
784		return ZFCP_ERP_FAILED;
785	}
786
787	atomic_set_mask(ZFCP_STATUS_COMMON_OPEN, &adapter->status);
788
789	return ZFCP_ERP_SUCCEEDED;
790}
791
792static int zfcp_erp_adapter_strategy(struct zfcp_erp_action *act)
793{
794	struct zfcp_adapter *adapter = act->adapter;
795
796	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_OPEN) {
797		zfcp_erp_adapter_strategy_close(act);
798		if (act->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
799			return ZFCP_ERP_EXIT;
800	}
801
802	if (zfcp_erp_adapter_strategy_open(act)) {
803		ssleep(8);
804		return ZFCP_ERP_FAILED;
805	}
806
807	return ZFCP_ERP_SUCCEEDED;
808}
809
810static int zfcp_erp_port_forced_strategy_close(struct zfcp_erp_action *act)
811{
812	int retval;
813
814	retval = zfcp_fsf_close_physical_port(act);
815	if (retval == -ENOMEM)
816		return ZFCP_ERP_NOMEM;
817	act->step = ZFCP_ERP_STEP_PHYS_PORT_CLOSING;
818	if (retval)
819		return ZFCP_ERP_FAILED;
820
821	return ZFCP_ERP_CONTINUES;
822}
823
824static int zfcp_erp_port_forced_strategy(struct zfcp_erp_action *erp_action)
825{
826	struct zfcp_port *port = erp_action->port;
827	int status = atomic_read(&port->status);
828
829	switch (erp_action->step) {
830	case ZFCP_ERP_STEP_UNINITIALIZED:
831		if ((status & ZFCP_STATUS_PORT_PHYS_OPEN) &&
832		    (status & ZFCP_STATUS_COMMON_OPEN))
833			return zfcp_erp_port_forced_strategy_close(erp_action);
834		else
835			return ZFCP_ERP_FAILED;
836
837	case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
838		if (!(status & ZFCP_STATUS_PORT_PHYS_OPEN))
839			return ZFCP_ERP_SUCCEEDED;
840	}
841	return ZFCP_ERP_FAILED;
842}
843
844static int zfcp_erp_port_strategy_close(struct zfcp_erp_action *erp_action)
845{
846	int retval;
847
848	retval = zfcp_fsf_close_port(erp_action);
849	if (retval == -ENOMEM)
850		return ZFCP_ERP_NOMEM;
851	erp_action->step = ZFCP_ERP_STEP_PORT_CLOSING;
852	if (retval)
853		return ZFCP_ERP_FAILED;
854	return ZFCP_ERP_CONTINUES;
855}
856
857static int zfcp_erp_port_strategy_open_port(struct zfcp_erp_action *erp_action)
858{
859	int retval;
860
861	retval = zfcp_fsf_open_port(erp_action);
862	if (retval == -ENOMEM)
863		return ZFCP_ERP_NOMEM;
864	erp_action->step = ZFCP_ERP_STEP_PORT_OPENING;
865	if (retval)
866		return ZFCP_ERP_FAILED;
867	return ZFCP_ERP_CONTINUES;
868}
869
870static int zfcp_erp_open_ptp_port(struct zfcp_erp_action *act)
871{
872	struct zfcp_adapter *adapter = act->adapter;
873	struct zfcp_port *port = act->port;
874
875	if (port->wwpn != adapter->peer_wwpn) {
876		zfcp_erp_set_port_status(port, ZFCP_STATUS_COMMON_ERP_FAILED);
877		return ZFCP_ERP_FAILED;
878	}
879	port->d_id = adapter->peer_d_id;
880	return zfcp_erp_port_strategy_open_port(act);
881}
882
883static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
884{
885	struct zfcp_adapter *adapter = act->adapter;
886	struct zfcp_port *port = act->port;
887	int p_status = atomic_read(&port->status);
888
889	switch (act->step) {
890	case ZFCP_ERP_STEP_UNINITIALIZED:
891	case ZFCP_ERP_STEP_PHYS_PORT_CLOSING:
892	case ZFCP_ERP_STEP_PORT_CLOSING:
893		if (fc_host_port_type(adapter->scsi_host) == FC_PORTTYPE_PTP)
894			return zfcp_erp_open_ptp_port(act);
895		if (!port->d_id) {
896			zfcp_fc_trigger_did_lookup(port);
897			return ZFCP_ERP_EXIT;
898		}
899		return zfcp_erp_port_strategy_open_port(act);
900
901	case ZFCP_ERP_STEP_PORT_OPENING:
902		/* D_ID might have changed during open */
903		if (p_status & ZFCP_STATUS_COMMON_OPEN) {
904			if (!port->d_id) {
905				zfcp_fc_trigger_did_lookup(port);
906				return ZFCP_ERP_EXIT;
907			}
908			return ZFCP_ERP_SUCCEEDED;
909		}
910		if (port->d_id && !(p_status & ZFCP_STATUS_COMMON_NOESC)) {
911			port->d_id = 0;
912			return ZFCP_ERP_FAILED;
913		}
914		/* fall through otherwise */
915	}
916	return ZFCP_ERP_FAILED;
917}
918
919static int zfcp_erp_port_strategy(struct zfcp_erp_action *erp_action)
920{
921	struct zfcp_port *port = erp_action->port;
922	int p_status = atomic_read(&port->status);
923
924	if ((p_status & ZFCP_STATUS_COMMON_NOESC) &&
925	    !(p_status & ZFCP_STATUS_COMMON_OPEN))
926		goto close_init_done;
927
928	switch (erp_action->step) {
929	case ZFCP_ERP_STEP_UNINITIALIZED:
930		if (p_status & ZFCP_STATUS_COMMON_OPEN)
931			return zfcp_erp_port_strategy_close(erp_action);
932		break;
933
934	case ZFCP_ERP_STEP_PORT_CLOSING:
935		if (p_status & ZFCP_STATUS_COMMON_OPEN)
936			return ZFCP_ERP_FAILED;
937		break;
938	}
939
940close_init_done:
941	if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
942		return ZFCP_ERP_EXIT;
943
944	return zfcp_erp_port_strategy_open_common(erp_action);
945}
946
947static void zfcp_erp_lun_strategy_clearstati(struct scsi_device *sdev)
948{
949	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
950
951	atomic_clear_mask(ZFCP_STATUS_COMMON_ACCESS_DENIED,
952			  &zfcp_sdev->status);
953}
954
955static int zfcp_erp_lun_strategy_close(struct zfcp_erp_action *erp_action)
956{
957	int retval = zfcp_fsf_close_lun(erp_action);
958	if (retval == -ENOMEM)
959		return ZFCP_ERP_NOMEM;
960	erp_action->step = ZFCP_ERP_STEP_LUN_CLOSING;
961	if (retval)
962		return ZFCP_ERP_FAILED;
963	return ZFCP_ERP_CONTINUES;
964}
965
966static int zfcp_erp_lun_strategy_open(struct zfcp_erp_action *erp_action)
967{
968	int retval = zfcp_fsf_open_lun(erp_action);
969	if (retval == -ENOMEM)
970		return ZFCP_ERP_NOMEM;
971	erp_action->step = ZFCP_ERP_STEP_LUN_OPENING;
972	if (retval)
973		return  ZFCP_ERP_FAILED;
974	return ZFCP_ERP_CONTINUES;
975}
976
977static int zfcp_erp_lun_strategy(struct zfcp_erp_action *erp_action)
978{
979	struct scsi_device *sdev = erp_action->sdev;
980	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
981
982	switch (erp_action->step) {
983	case ZFCP_ERP_STEP_UNINITIALIZED:
984		zfcp_erp_lun_strategy_clearstati(sdev);
985		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
986			return zfcp_erp_lun_strategy_close(erp_action);
987		/* already closed, fall through */
988	case ZFCP_ERP_STEP_LUN_CLOSING:
989		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
990			return ZFCP_ERP_FAILED;
991		if (erp_action->status & ZFCP_STATUS_ERP_CLOSE_ONLY)
992			return ZFCP_ERP_EXIT;
993		return zfcp_erp_lun_strategy_open(erp_action);
994
995	case ZFCP_ERP_STEP_LUN_OPENING:
996		if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN)
997			return ZFCP_ERP_SUCCEEDED;
998	}
999	return ZFCP_ERP_FAILED;
1000}
1001
1002static int zfcp_erp_strategy_check_lun(struct scsi_device *sdev, int result)
1003{
1004	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
1005
1006	switch (result) {
1007	case ZFCP_ERP_SUCCEEDED :
1008		atomic_set(&zfcp_sdev->erp_counter, 0);
1009		zfcp_erp_lun_unblock(sdev);
1010		break;
1011	case ZFCP_ERP_FAILED :
1012		atomic_inc(&zfcp_sdev->erp_counter);
1013		if (atomic_read(&zfcp_sdev->erp_counter) > ZFCP_MAX_ERPS) {
1014			dev_err(&zfcp_sdev->port->adapter->ccw_device->dev,
1015				"ERP failed for LUN 0x%016Lx on "
1016				"port 0x%016Lx\n",
1017				(unsigned long long)zfcp_scsi_dev_lun(sdev),
1018				(unsigned long long)zfcp_sdev->port->wwpn);
1019			zfcp_erp_set_lun_status(sdev,
1020						ZFCP_STATUS_COMMON_ERP_FAILED);
1021		}
1022		break;
1023	}
1024
1025	if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1026		zfcp_erp_lun_block(sdev, 0);
1027		result = ZFCP_ERP_EXIT;
1028	}
1029	return result;
1030}
1031
1032static int zfcp_erp_strategy_check_port(struct zfcp_port *port, int result)
1033{
1034	switch (result) {
1035	case ZFCP_ERP_SUCCEEDED :
1036		atomic_set(&port->erp_counter, 0);
1037		zfcp_erp_port_unblock(port);
1038		break;
1039
1040	case ZFCP_ERP_FAILED :
1041		if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_NOESC) {
1042			zfcp_erp_port_block(port, 0);
1043			result = ZFCP_ERP_EXIT;
1044		}
1045		atomic_inc(&port->erp_counter);
1046		if (atomic_read(&port->erp_counter) > ZFCP_MAX_ERPS) {
1047			dev_err(&port->adapter->ccw_device->dev,
1048				"ERP failed for remote port 0x%016Lx\n",
1049				(unsigned long long)port->wwpn);
1050			zfcp_erp_set_port_status(port,
1051					 ZFCP_STATUS_COMMON_ERP_FAILED);
1052		}
1053		break;
1054	}
1055
1056	if (atomic_read(&port->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1057		zfcp_erp_port_block(port, 0);
1058		result = ZFCP_ERP_EXIT;
1059	}
1060	return result;
1061}
1062
1063static int zfcp_erp_strategy_check_adapter(struct zfcp_adapter *adapter,
1064					   int result)
1065{
1066	switch (result) {
1067	case ZFCP_ERP_SUCCEEDED :
1068		atomic_set(&adapter->erp_counter, 0);
1069		zfcp_erp_adapter_unblock(adapter);
1070		break;
1071
1072	case ZFCP_ERP_FAILED :
1073		atomic_inc(&adapter->erp_counter);
1074		if (atomic_read(&adapter->erp_counter) > ZFCP_MAX_ERPS) {
1075			dev_err(&adapter->ccw_device->dev,
1076				"ERP cannot recover an error "
1077				"on the FCP device\n");
1078			zfcp_erp_set_adapter_status(adapter,
1079					    ZFCP_STATUS_COMMON_ERP_FAILED);
1080		}
1081		break;
1082	}
1083
1084	if (atomic_read(&adapter->status) & ZFCP_STATUS_COMMON_ERP_FAILED) {
1085		zfcp_erp_adapter_block(adapter, 0);
1086		result = ZFCP_ERP_EXIT;
1087	}
1088	return result;
1089}
1090
1091static int zfcp_erp_strategy_check_target(struct zfcp_erp_action *erp_action,
1092					  int result)
1093{
1094	struct zfcp_adapter *adapter = erp_action->adapter;
1095	struct zfcp_port *port = erp_action->port;
1096	struct scsi_device *sdev = erp_action->sdev;
1097
1098	switch (erp_action->action) {
1099
1100	case ZFCP_ERP_ACTION_REOPEN_LUN:
1101		result = zfcp_erp_strategy_check_lun(sdev, result);
1102		break;
1103
1104	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1105	case ZFCP_ERP_ACTION_REOPEN_PORT:
1106		result = zfcp_erp_strategy_check_port(port, result);
1107		break;
1108
1109	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1110		result = zfcp_erp_strategy_check_adapter(adapter, result);
1111		break;
1112	}
1113	return result;
1114}
1115
1116static int zfcp_erp_strat_change_det(atomic_t *target_status, u32 erp_status)
1117{
1118	int status = atomic_read(target_status);
1119
1120	if ((status & ZFCP_STATUS_COMMON_RUNNING) &&
1121	    (erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY))
1122		return 1; /* take it online */
1123
1124	if (!(status & ZFCP_STATUS_COMMON_RUNNING) &&
1125	    !(erp_status & ZFCP_STATUS_ERP_CLOSE_ONLY))
1126		return 1; /* take it offline */
1127
1128	return 0;
1129}
1130
1131static int zfcp_erp_strategy_statechange(struct zfcp_erp_action *act, int ret)
1132{
1133	int action = act->action;
1134	struct zfcp_adapter *adapter = act->adapter;
1135	struct zfcp_port *port = act->port;
1136	struct scsi_device *sdev = act->sdev;
1137	struct zfcp_scsi_dev *zfcp_sdev;
1138	u32 erp_status = act->status;
1139
1140	switch (action) {
1141	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1142		if (zfcp_erp_strat_change_det(&adapter->status, erp_status)) {
1143			_zfcp_erp_adapter_reopen(adapter,
1144						 ZFCP_STATUS_COMMON_ERP_FAILED,
1145						 "ersscg1");
1146			return ZFCP_ERP_EXIT;
1147		}
1148		break;
1149
1150	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1151	case ZFCP_ERP_ACTION_REOPEN_PORT:
1152		if (zfcp_erp_strat_change_det(&port->status, erp_status)) {
1153			_zfcp_erp_port_reopen(port,
1154					      ZFCP_STATUS_COMMON_ERP_FAILED,
1155					      "ersscg2");
1156			return ZFCP_ERP_EXIT;
1157		}
1158		break;
1159
1160	case ZFCP_ERP_ACTION_REOPEN_LUN:
1161		zfcp_sdev = sdev_to_zfcp(sdev);
1162		if (zfcp_erp_strat_change_det(&zfcp_sdev->status, erp_status)) {
1163			_zfcp_erp_lun_reopen(sdev,
1164					     ZFCP_STATUS_COMMON_ERP_FAILED,
1165					     "ersscg3", 0);
1166			return ZFCP_ERP_EXIT;
1167		}
1168		break;
1169	}
1170	return ret;
1171}
1172
1173static void zfcp_erp_action_dequeue(struct zfcp_erp_action *erp_action)
1174{
1175	struct zfcp_adapter *adapter = erp_action->adapter;
1176	struct zfcp_scsi_dev *zfcp_sdev;
1177
1178	adapter->erp_total_count--;
1179	if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) {
1180		adapter->erp_low_mem_count--;
1181		erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM;
1182	}
1183
1184	list_del(&erp_action->list);
1185	zfcp_dbf_rec_run("eractd1", erp_action);
1186
1187	switch (erp_action->action) {
1188	case ZFCP_ERP_ACTION_REOPEN_LUN:
1189		zfcp_sdev = sdev_to_zfcp(erp_action->sdev);
1190		atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1191				  &zfcp_sdev->status);
1192		break;
1193
1194	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1195	case ZFCP_ERP_ACTION_REOPEN_PORT:
1196		atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1197				  &erp_action->port->status);
1198		break;
1199
1200	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1201		atomic_clear_mask(ZFCP_STATUS_COMMON_ERP_INUSE,
1202				  &erp_action->adapter->status);
1203		break;
1204	}
1205}
1206
1207static void zfcp_erp_action_cleanup(struct zfcp_erp_action *act, int result)
1208{
1209	struct zfcp_adapter *adapter = act->adapter;
1210	struct zfcp_port *port = act->port;
1211	struct scsi_device *sdev = act->sdev;
1212
1213	switch (act->action) {
1214	case ZFCP_ERP_ACTION_REOPEN_LUN:
1215		if (!(act->status & ZFCP_STATUS_ERP_NO_REF))
1216			scsi_device_put(sdev);
1217		break;
1218
1219	case ZFCP_ERP_ACTION_REOPEN_PORT:
1220		if (result == ZFCP_ERP_SUCCEEDED)
1221			zfcp_scsi_schedule_rport_register(port);
1222		/* fall through */
1223	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1224		put_device(&port->dev);
1225		break;
1226
1227	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1228		if (result == ZFCP_ERP_SUCCEEDED) {
1229			register_service_level(&adapter->service_level);
1230			zfcp_fc_conditional_port_scan(adapter);
1231			queue_work(adapter->work_queue, &adapter->ns_up_work);
1232		} else
1233			unregister_service_level(&adapter->service_level);
1234
1235		kref_put(&adapter->ref, zfcp_adapter_release);
1236		break;
1237	}
1238}
1239
1240static int zfcp_erp_strategy_do_action(struct zfcp_erp_action *erp_action)
1241{
1242	switch (erp_action->action) {
1243	case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
1244		return zfcp_erp_adapter_strategy(erp_action);
1245	case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
1246		return zfcp_erp_port_forced_strategy(erp_action);
1247	case ZFCP_ERP_ACTION_REOPEN_PORT:
1248		return zfcp_erp_port_strategy(erp_action);
1249	case ZFCP_ERP_ACTION_REOPEN_LUN:
1250		return zfcp_erp_lun_strategy(erp_action);
1251	}
1252	return ZFCP_ERP_FAILED;
1253}
1254
1255static int zfcp_erp_strategy(struct zfcp_erp_action *erp_action)
1256{
1257	int retval;
1258	unsigned long flags;
1259	struct zfcp_adapter *adapter = erp_action->adapter;
1260
1261	kref_get(&adapter->ref);
1262
1263	write_lock_irqsave(&adapter->erp_lock, flags);
1264	zfcp_erp_strategy_check_fsfreq(erp_action);
1265
1266	if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED) {
1267		zfcp_erp_action_dequeue(erp_action);
1268		retval = ZFCP_ERP_DISMISSED;
1269		goto unlock;
1270	}
1271
1272	if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) {
1273		retval = ZFCP_ERP_FAILED;
1274		goto check_target;
1275	}
1276
1277	zfcp_erp_action_to_running(erp_action);
1278
1279	/* no lock to allow for blocking operations */
1280	write_unlock_irqrestore(&adapter->erp_lock, flags);
1281	retval = zfcp_erp_strategy_do_action(erp_action);
1282	write_lock_irqsave(&adapter->erp_lock, flags);
1283
1284	if (erp_action->status & ZFCP_STATUS_ERP_DISMISSED)
1285		retval = ZFCP_ERP_CONTINUES;
1286
1287	switch (retval) {
1288	case ZFCP_ERP_NOMEM:
1289		if (!(erp_action->status & ZFCP_STATUS_ERP_LOWMEM)) {
1290			++adapter->erp_low_mem_count;
1291			erp_action->status |= ZFCP_STATUS_ERP_LOWMEM;
1292		}
1293		if (adapter->erp_total_count == adapter->erp_low_mem_count)
1294			_zfcp_erp_adapter_reopen(adapter, 0, "erstgy1");
1295		else {
1296			zfcp_erp_strategy_memwait(erp_action);
1297			retval = ZFCP_ERP_CONTINUES;
1298		}
1299		goto unlock;
1300
1301	case ZFCP_ERP_CONTINUES:
1302		if (erp_action->status & ZFCP_STATUS_ERP_LOWMEM) {
1303			--adapter->erp_low_mem_count;
1304			erp_action->status &= ~ZFCP_STATUS_ERP_LOWMEM;
1305		}
1306		goto unlock;
1307	}
1308
1309check_target:
1310	retval = zfcp_erp_strategy_check_target(erp_action, retval);
1311	zfcp_erp_action_dequeue(erp_action);
1312	retval = zfcp_erp_strategy_statechange(erp_action, retval);
1313	if (retval == ZFCP_ERP_EXIT)
1314		goto unlock;
1315	if (retval == ZFCP_ERP_SUCCEEDED)
1316		zfcp_erp_strategy_followup_success(erp_action);
1317	if (retval == ZFCP_ERP_FAILED)
1318		zfcp_erp_strategy_followup_failed(erp_action);
1319
1320 unlock:
1321	write_unlock_irqrestore(&adapter->erp_lock, flags);
1322
1323	if (retval != ZFCP_ERP_CONTINUES)
1324		zfcp_erp_action_cleanup(erp_action, retval);
1325
1326	kref_put(&adapter->ref, zfcp_adapter_release);
1327	return retval;
1328}
1329
1330static int zfcp_erp_thread(void *data)
1331{
1332	struct zfcp_adapter *adapter = (struct zfcp_adapter *) data;
1333	struct list_head *next;
1334	struct zfcp_erp_action *act;
1335	unsigned long flags;
1336
1337	for (;;) {
1338		wait_event_interruptible(adapter->erp_ready_wq,
1339			   !list_empty(&adapter->erp_ready_head) ||
1340			   kthread_should_stop());
1341
1342		if (kthread_should_stop())
1343			break;
1344
1345		write_lock_irqsave(&adapter->erp_lock, flags);
1346		next = adapter->erp_ready_head.next;
1347		write_unlock_irqrestore(&adapter->erp_lock, flags);
1348
1349		if (next != &adapter->erp_ready_head) {
1350			act = list_entry(next, struct zfcp_erp_action, list);
1351
1352			/* there is more to come after dismission, no notify */
1353			if (zfcp_erp_strategy(act) != ZFCP_ERP_DISMISSED)
1354				zfcp_erp_wakeup(adapter);
1355		}
1356	}
1357
1358	return 0;
1359}
1360
1361/**
1362 * zfcp_erp_thread_setup - Start ERP thread for adapter
1363 * @adapter: Adapter to start the ERP thread for
1364 *
1365 * Returns 0 on success or error code from kernel_thread()
1366 */
1367int zfcp_erp_thread_setup(struct zfcp_adapter *adapter)
1368{
1369	struct task_struct *thread;
1370
1371	thread = kthread_run(zfcp_erp_thread, adapter, "zfcperp%s",
1372			     dev_name(&adapter->ccw_device->dev));
1373	if (IS_ERR(thread)) {
1374		dev_err(&adapter->ccw_device->dev,
1375			"Creating an ERP thread for the FCP device failed.\n");
1376		return PTR_ERR(thread);
1377	}
1378
1379	adapter->erp_thread = thread;
1380	return 0;
1381}
1382
1383/**
1384 * zfcp_erp_thread_kill - Stop ERP thread.
1385 * @adapter: Adapter where the ERP thread should be stopped.
1386 *
1387 * The caller of this routine ensures that the specified adapter has
1388 * been shut down and that this operation has been completed. Thus,
1389 * there are no pending erp_actions which would need to be handled
1390 * here.
1391 */
1392void zfcp_erp_thread_kill(struct zfcp_adapter *adapter)
1393{
1394	kthread_stop(adapter->erp_thread);
1395	adapter->erp_thread = NULL;
1396	WARN_ON(!list_empty(&adapter->erp_ready_head));
1397	WARN_ON(!list_empty(&adapter->erp_running_head));
1398}
1399
1400/**
1401 * zfcp_erp_wait - wait for completion of error recovery on an adapter
1402 * @adapter: adapter for which to wait for completion of its error recovery
1403 */
1404void zfcp_erp_wait(struct zfcp_adapter *adapter)
1405{
1406	wait_event(adapter->erp_done_wqh,
1407		   !(atomic_read(&adapter->status) &
1408			ZFCP_STATUS_ADAPTER_ERP_PENDING));
1409}
1410
1411/**
1412 * zfcp_erp_set_adapter_status - set adapter status bits
1413 * @adapter: adapter to change the status
1414 * @mask: status bits to change
1415 *
1416 * Changes in common status bits are propagated to attached ports and LUNs.
1417 */
1418void zfcp_erp_set_adapter_status(struct zfcp_adapter *adapter, u32 mask)
1419{
1420	struct zfcp_port *port;
1421	struct scsi_device *sdev;
1422	unsigned long flags;
1423	u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1424
1425	atomic_set_mask(mask, &adapter->status);
1426
1427	if (!common_mask)
1428		return;
1429
1430	read_lock_irqsave(&adapter->port_list_lock, flags);
1431	list_for_each_entry(port, &adapter->port_list, list)
1432		atomic_set_mask(common_mask, &port->status);
1433	read_unlock_irqrestore(&adapter->port_list_lock, flags);
1434
1435	spin_lock_irqsave(adapter->scsi_host->host_lock, flags);
1436	__shost_for_each_device(sdev, adapter->scsi_host)
1437		atomic_set_mask(common_mask, &sdev_to_zfcp(sdev)->status);
1438	spin_unlock_irqrestore(adapter->scsi_host->host_lock, flags);
1439}
1440
1441/**
1442 * zfcp_erp_clear_adapter_status - clear adapter status bits
1443 * @adapter: adapter to change the status
1444 * @mask: status bits to change
1445 *
1446 * Changes in common status bits are propagated to attached ports and LUNs.
1447 */
1448void zfcp_erp_clear_adapter_status(struct zfcp_adapter *adapter, u32 mask)
1449{
1450	struct zfcp_port *port;
1451	struct scsi_device *sdev;
1452	unsigned long flags;
1453	u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1454	u32 clear_counter = mask & ZFCP_STATUS_COMMON_ERP_FAILED;
1455
1456	atomic_clear_mask(mask, &adapter->status);
1457
1458	if (!common_mask)
1459		return;
1460
1461	if (clear_counter)
1462		atomic_set(&adapter->erp_counter, 0);
1463
1464	read_lock_irqsave(&adapter->port_list_lock, flags);
1465	list_for_each_entry(port, &adapter->port_list, list) {
1466		atomic_clear_mask(common_mask, &port->status);
1467		if (clear_counter)
1468			atomic_set(&port->erp_counter, 0);
1469	}
1470	read_unlock_irqrestore(&adapter->port_list_lock, flags);
1471
1472	spin_lock_irqsave(adapter->scsi_host->host_lock, flags);
1473	__shost_for_each_device(sdev, adapter->scsi_host) {
1474		atomic_clear_mask(common_mask, &sdev_to_zfcp(sdev)->status);
1475		if (clear_counter)
1476			atomic_set(&sdev_to_zfcp(sdev)->erp_counter, 0);
1477	}
1478	spin_unlock_irqrestore(adapter->scsi_host->host_lock, flags);
1479}
1480
1481/**
1482 * zfcp_erp_set_port_status - set port status bits
1483 * @port: port to change the status
1484 * @mask: status bits to change
1485 *
1486 * Changes in common status bits are propagated to attached LUNs.
1487 */
1488void zfcp_erp_set_port_status(struct zfcp_port *port, u32 mask)
1489{
1490	struct scsi_device *sdev;
1491	u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1492	unsigned long flags;
1493
1494	atomic_set_mask(mask, &port->status);
1495
1496	if (!common_mask)
1497		return;
1498
1499	spin_lock_irqsave(port->adapter->scsi_host->host_lock, flags);
1500	__shost_for_each_device(sdev, port->adapter->scsi_host)
1501		if (sdev_to_zfcp(sdev)->port == port)
1502			atomic_set_mask(common_mask,
1503					&sdev_to_zfcp(sdev)->status);
1504	spin_unlock_irqrestore(port->adapter->scsi_host->host_lock, flags);
1505}
1506
1507/**
1508 * zfcp_erp_clear_port_status - clear port status bits
1509 * @port: adapter to change the status
1510 * @mask: status bits to change
1511 *
1512 * Changes in common status bits are propagated to attached LUNs.
1513 */
1514void zfcp_erp_clear_port_status(struct zfcp_port *port, u32 mask)
1515{
1516	struct scsi_device *sdev;
1517	u32 common_mask = mask & ZFCP_COMMON_FLAGS;
1518	u32 clear_counter = mask & ZFCP_STATUS_COMMON_ERP_FAILED;
1519	unsigned long flags;
1520
1521	atomic_clear_mask(mask, &port->status);
1522
1523	if (!common_mask)
1524		return;
1525
1526	if (clear_counter)
1527		atomic_set(&port->erp_counter, 0);
1528
1529	spin_lock_irqsave(port->adapter->scsi_host->host_lock, flags);
1530	__shost_for_each_device(sdev, port->adapter->scsi_host)
1531		if (sdev_to_zfcp(sdev)->port == port) {
1532			atomic_clear_mask(common_mask,
1533					  &sdev_to_zfcp(sdev)->status);
1534			if (clear_counter)
1535				atomic_set(&sdev_to_zfcp(sdev)->erp_counter, 0);
1536		}
1537	spin_unlock_irqrestore(port->adapter->scsi_host->host_lock, flags);
1538}
1539
1540/**
1541 * zfcp_erp_set_lun_status - set lun status bits
1542 * @sdev: SCSI device / lun to set the status bits
1543 * @mask: status bits to change
1544 */
1545void zfcp_erp_set_lun_status(struct scsi_device *sdev, u32 mask)
1546{
1547	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
1548
1549	atomic_set_mask(mask, &zfcp_sdev->status);
1550}
1551
1552/**
1553 * zfcp_erp_clear_lun_status - clear lun status bits
1554 * @sdev: SCSi device / lun to clear the status bits
1555 * @mask: status bits to change
1556 */
1557void zfcp_erp_clear_lun_status(struct scsi_device *sdev, u32 mask)
1558{
1559	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
1560
1561	atomic_clear_mask(mask, &zfcp_sdev->status);
1562
1563	if (mask & ZFCP_STATUS_COMMON_ERP_FAILED)
1564		atomic_set(&zfcp_sdev->erp_counter, 0);
1565}
1566
1567