[S390] cio: provide fake irb for transport mode IO
[linux-2.6.git] / drivers / s390 / cio / device_fsm.c
1 /*
2  * drivers/s390/cio/device_fsm.c
3  * finite state machine for device handling
4  *
5  *    Copyright IBM Corp. 2002,2008
6  *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  */
9
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/jiffies.h>
13 #include <linux/string.h>
14
15 #include <asm/ccwdev.h>
16 #include <asm/cio.h>
17 #include <asm/chpid.h>
18
19 #include "cio.h"
20 #include "cio_debug.h"
21 #include "css.h"
22 #include "device.h"
23 #include "chsc.h"
24 #include "ioasm.h"
25 #include "chp.h"
26
27 static int timeout_log_enabled;
28
29 static int __init ccw_timeout_log_setup(char *unused)
30 {
31         timeout_log_enabled = 1;
32         return 1;
33 }
34
35 __setup("ccw_timeout_log", ccw_timeout_log_setup);
36
37 static void ccw_timeout_log(struct ccw_device *cdev)
38 {
39         struct schib schib;
40         struct subchannel *sch;
41         struct io_subchannel_private *private;
42         union orb *orb;
43         int cc;
44
45         sch = to_subchannel(cdev->dev.parent);
46         private = to_io_private(sch);
47         orb = &private->orb;
48         cc = stsch_err(sch->schid, &schib);
49
50         printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
51                "device information:\n", get_clock());
52         printk(KERN_WARNING "cio: orb:\n");
53         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
54                        orb, sizeof(*orb), 0);
55         printk(KERN_WARNING "cio: ccw device bus id: %s\n",
56                dev_name(&cdev->dev));
57         printk(KERN_WARNING "cio: subchannel bus id: %s\n",
58                dev_name(&sch->dev));
59         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
60                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
61
62         if (orb->tm.b) {
63                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
64                 printk(KERN_WARNING "cio: last tcw:\n");
65                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
66                                (void *)(addr_t)orb->tm.tcw,
67                                sizeof(struct tcw), 0);
68         } else {
69                 printk(KERN_WARNING "cio: orb indicates command mode\n");
70                 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
71                     (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
72                         printk(KERN_WARNING "cio: last channel program "
73                                "(intern):\n");
74                 else
75                         printk(KERN_WARNING "cio: last channel program:\n");
76
77                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
78                                (void *)(addr_t)orb->cmd.cpa,
79                                sizeof(struct ccw1), 0);
80         }
81         printk(KERN_WARNING "cio: ccw device state: %d\n",
82                cdev->private->state);
83         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
84         printk(KERN_WARNING "cio: schib:\n");
85         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
86                        &schib, sizeof(schib), 0);
87         printk(KERN_WARNING "cio: ccw device flags:\n");
88         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
89                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
90 }
91
92 /*
93  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
94  */
95 static void
96 ccw_device_timeout(unsigned long data)
97 {
98         struct ccw_device *cdev;
99
100         cdev = (struct ccw_device *) data;
101         spin_lock_irq(cdev->ccwlock);
102         if (timeout_log_enabled)
103                 ccw_timeout_log(cdev);
104         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
105         spin_unlock_irq(cdev->ccwlock);
106 }
107
108 /*
109  * Set timeout
110  */
111 void
112 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
113 {
114         if (expires == 0) {
115                 del_timer(&cdev->private->timer);
116                 return;
117         }
118         if (timer_pending(&cdev->private->timer)) {
119                 if (mod_timer(&cdev->private->timer, jiffies + expires))
120                         return;
121         }
122         cdev->private->timer.function = ccw_device_timeout;
123         cdev->private->timer.data = (unsigned long) cdev;
124         cdev->private->timer.expires = jiffies + expires;
125         add_timer(&cdev->private->timer);
126 }
127
128 /*
129  * Cancel running i/o. This is called repeatedly since halt/clear are
130  * asynchronous operations. We do one try with cio_cancel, two tries
131  * with cio_halt, 255 tries with cio_clear. If everythings fails panic.
132  * Returns 0 if device now idle, -ENODEV for device not operational and
133  * -EBUSY if an interrupt is expected (either from halt/clear or from a
134  * status pending).
135  */
136 int
137 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
138 {
139         struct subchannel *sch;
140         int ret;
141
142         sch = to_subchannel(cdev->dev.parent);
143         if (cio_update_schib(sch))
144                 return -ENODEV; 
145         if (!sch->schib.pmcw.ena)
146                 /* Not operational -> done. */
147                 return 0;
148         /* Stage 1: cancel io. */
149         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
150             !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
151                 if (!scsw_is_tm(&sch->schib.scsw)) {
152                         ret = cio_cancel(sch);
153                         if (ret != -EINVAL)
154                                 return ret;
155                 }
156                 /* cancel io unsuccessful or not applicable (transport mode).
157                  * Continue with asynchronous instructions. */
158                 cdev->private->iretry = 3;      /* 3 halt retries. */
159         }
160         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
161                 /* Stage 2: halt io. */
162                 if (cdev->private->iretry) {
163                         cdev->private->iretry--;
164                         ret = cio_halt(sch);
165                         if (ret != -EBUSY)
166                                 return (ret == 0) ? -EBUSY : ret;
167                 }
168                 /* halt io unsuccessful. */
169                 cdev->private->iretry = 255;    /* 255 clear retries. */
170         }
171         /* Stage 3: clear io. */
172         if (cdev->private->iretry) {
173                 cdev->private->iretry--;
174                 ret = cio_clear (sch);
175                 return (ret == 0) ? -EBUSY : ret;
176         }
177         /* Function was unsuccessful */
178         CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
179                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno);
180         return -EIO;
181 }
182
183 void ccw_device_update_sense_data(struct ccw_device *cdev)
184 {
185         memset(&cdev->id, 0, sizeof(cdev->id));
186         cdev->id.cu_type   = cdev->private->senseid.cu_type;
187         cdev->id.cu_model  = cdev->private->senseid.cu_model;
188         cdev->id.dev_type  = cdev->private->senseid.dev_type;
189         cdev->id.dev_model = cdev->private->senseid.dev_model;
190 }
191
192 int ccw_device_test_sense_data(struct ccw_device *cdev)
193 {
194         return cdev->id.cu_type == cdev->private->senseid.cu_type &&
195                 cdev->id.cu_model == cdev->private->senseid.cu_model &&
196                 cdev->id.dev_type == cdev->private->senseid.dev_type &&
197                 cdev->id.dev_model == cdev->private->senseid.dev_model;
198 }
199
200 /*
201  * The machine won't give us any notification by machine check if a chpid has
202  * been varied online on the SE so we have to find out by magic (i. e. driving
203  * the channel subsystem to device selection and updating our path masks).
204  */
205 static void
206 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
207 {
208         int mask, i;
209         struct chp_id chpid;
210
211         chp_id_init(&chpid);
212         for (i = 0; i<8; i++) {
213                 mask = 0x80 >> i;
214                 if (!(sch->lpm & mask))
215                         continue;
216                 if (old_lpm & mask)
217                         continue;
218                 chpid.id = sch->schib.pmcw.chpid[i];
219                 if (!chp_is_registered(chpid))
220                         css_schedule_eval_all();
221         }
222 }
223
224 /*
225  * Stop device recognition.
226  */
227 static void
228 ccw_device_recog_done(struct ccw_device *cdev, int state)
229 {
230         struct subchannel *sch;
231         int old_lpm;
232
233         sch = to_subchannel(cdev->dev.parent);
234
235         if (cio_disable_subchannel(sch))
236                 state = DEV_STATE_NOT_OPER;
237         /*
238          * Now that we tried recognition, we have performed device selection
239          * through ssch() and the path information is up to date.
240          */
241         old_lpm = sch->lpm;
242
243         /* Check since device may again have become not operational. */
244         if (cio_update_schib(sch))
245                 state = DEV_STATE_NOT_OPER;
246         else
247                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
248
249         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
250                 /* Force reprobe on all chpids. */
251                 old_lpm = 0;
252         if (sch->lpm != old_lpm)
253                 __recover_lost_chpids(sch, old_lpm);
254         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
255             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
256                 cdev->private->flags.recog_done = 1;
257                 cdev->private->state = DEV_STATE_DISCONNECTED;
258                 wake_up(&cdev->private->wait_q);
259                 return;
260         }
261         if (cdev->private->flags.resuming) {
262                 cdev->private->state = state;
263                 cdev->private->flags.recog_done = 1;
264                 wake_up(&cdev->private->wait_q);
265                 return;
266         }
267         switch (state) {
268         case DEV_STATE_NOT_OPER:
269                 break;
270         case DEV_STATE_OFFLINE:
271                 if (!cdev->online) {
272                         ccw_device_update_sense_data(cdev);
273                         break;
274                 }
275                 cdev->private->state = DEV_STATE_OFFLINE;
276                 cdev->private->flags.recog_done = 1;
277                 if (ccw_device_test_sense_data(cdev)) {
278                         cdev->private->flags.donotify = 1;
279                         ccw_device_online(cdev);
280                         wake_up(&cdev->private->wait_q);
281                 } else {
282                         ccw_device_update_sense_data(cdev);
283                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
284                 }
285                 return;
286         case DEV_STATE_BOXED:
287                 if (cdev->id.cu_type != 0) { /* device was recognized before */
288                         cdev->private->flags.recog_done = 1;
289                         cdev->private->state = DEV_STATE_BOXED;
290                         wake_up(&cdev->private->wait_q);
291                         return;
292                 }
293                 break;
294         }
295         cdev->private->state = state;
296         io_subchannel_recog_done(cdev);
297         wake_up(&cdev->private->wait_q);
298 }
299
300 /*
301  * Function called from device_id.c after sense id has completed.
302  */
303 void
304 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
305 {
306         switch (err) {
307         case 0:
308                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
309                 break;
310         case -ETIME:            /* Sense id stopped by timeout. */
311                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
312                 break;
313         default:
314                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
315                 break;
316         }
317 }
318
319 /**
320   * ccw_device_notify() - inform the device's driver about an event
321   * @cdev: device for which an event occurred
322   * @event: event that occurred
323   *
324   * Returns:
325   *   -%EINVAL if the device is offline or has no driver.
326   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
327   *   %NOTIFY_OK if the driver wants to keep the device.
328   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
329   */
330 int ccw_device_notify(struct ccw_device *cdev, int event)
331 {
332         int ret = -EINVAL;
333
334         if (!cdev->drv)
335                 goto out;
336         if (!cdev->online)
337                 goto out;
338         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
339                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
340                       event);
341         if (!cdev->drv->notify) {
342                 ret = -EOPNOTSUPP;
343                 goto out;
344         }
345         if (cdev->drv->notify(cdev, event))
346                 ret = NOTIFY_OK;
347         else
348                 ret = NOTIFY_BAD;
349 out:
350         return ret;
351 }
352
353 static void ccw_device_oper_notify(struct ccw_device *cdev)
354 {
355         struct subchannel *sch = to_subchannel(cdev->dev.parent);
356
357         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
358                 /* Reenable channel measurements, if needed. */
359                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
360                 /* Save indication for new paths. */
361                 cdev->private->path_new_mask = sch->vpm;
362                 return;
363         }
364         /* Driver doesn't want device back. */
365         ccw_device_set_notoper(cdev);
366         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
367 }
368
369 /*
370  * Finished with online/offline processing.
371  */
372 static void
373 ccw_device_done(struct ccw_device *cdev, int state)
374 {
375         struct subchannel *sch;
376
377         sch = to_subchannel(cdev->dev.parent);
378
379         ccw_device_set_timeout(cdev, 0);
380
381         if (state != DEV_STATE_ONLINE)
382                 cio_disable_subchannel(sch);
383
384         /* Reset device status. */
385         memset(&cdev->private->irb, 0, sizeof(struct irb));
386
387         cdev->private->state = state;
388
389         switch (state) {
390         case DEV_STATE_BOXED:
391                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
392                               cdev->private->dev_id.devno, sch->schid.sch_no);
393                 if (cdev->online &&
394                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
395                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
396                 cdev->private->flags.donotify = 0;
397                 break;
398         case DEV_STATE_NOT_OPER:
399                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
400                               cdev->private->dev_id.devno, sch->schid.sch_no);
401                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
402                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
403                 else
404                         ccw_device_set_disconnected(cdev);
405                 cdev->private->flags.donotify = 0;
406                 break;
407         case DEV_STATE_DISCONNECTED:
408                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
409                               "%04x\n", cdev->private->dev_id.devno,
410                               sch->schid.sch_no);
411                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
412                         cdev->private->state = DEV_STATE_NOT_OPER;
413                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
414                 } else
415                         ccw_device_set_disconnected(cdev);
416                 cdev->private->flags.donotify = 0;
417                 break;
418         default:
419                 break;
420         }
421
422         if (cdev->private->flags.donotify) {
423                 cdev->private->flags.donotify = 0;
424                 ccw_device_oper_notify(cdev);
425         }
426         wake_up(&cdev->private->wait_q);
427 }
428
429 /*
430  * Start device recognition.
431  */
432 void ccw_device_recognition(struct ccw_device *cdev)
433 {
434         struct subchannel *sch = to_subchannel(cdev->dev.parent);
435
436         /*
437          * We used to start here with a sense pgid to find out whether a device
438          * is locked by someone else. Unfortunately, the sense pgid command
439          * code has other meanings on devices predating the path grouping
440          * algorithm, so we start with sense id and box the device after an
441          * timeout (or if sense pgid during path verification detects the device
442          * is locked, as may happen on newer devices).
443          */
444         cdev->private->flags.recog_done = 0;
445         cdev->private->state = DEV_STATE_SENSE_ID;
446         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
447                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
448                 return;
449         }
450         ccw_device_sense_id_start(cdev);
451 }
452
453 /*
454  * Handle events for states that use the ccw request infrastructure.
455  */
456 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
457 {
458         switch (e) {
459         case DEV_EVENT_NOTOPER:
460                 ccw_request_notoper(cdev);
461                 break;
462         case DEV_EVENT_INTERRUPT:
463                 ccw_request_handler(cdev);
464                 break;
465         case DEV_EVENT_TIMEOUT:
466                 ccw_request_timeout(cdev);
467                 break;
468         default:
469                 break;
470         }
471 }
472
473 static void ccw_device_report_path_events(struct ccw_device *cdev)
474 {
475         struct subchannel *sch = to_subchannel(cdev->dev.parent);
476         int path_event[8];
477         int chp, mask;
478
479         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
480                 path_event[chp] = PE_NONE;
481                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
482                         path_event[chp] |= PE_PATH_GONE;
483                 if (mask & cdev->private->path_new_mask & sch->vpm)
484                         path_event[chp] |= PE_PATH_AVAILABLE;
485                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
486                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
487         }
488         if (cdev->online && cdev->drv->path_event)
489                 cdev->drv->path_event(cdev, path_event);
490 }
491
492 static void ccw_device_reset_path_events(struct ccw_device *cdev)
493 {
494         cdev->private->path_gone_mask = 0;
495         cdev->private->path_new_mask = 0;
496         cdev->private->pgid_reset_mask = 0;
497 }
498
499 static void create_fake_irb(struct irb *irb, int type)
500 {
501         memset(irb, 0, sizeof(*irb));
502         if (type == FAKE_CMD_IRB) {
503                 struct cmd_scsw *scsw = &irb->scsw.cmd;
504                 scsw->cc = 1;
505                 scsw->fctl = SCSW_FCTL_START_FUNC;
506                 scsw->actl = SCSW_ACTL_START_PEND;
507                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
508         } else if (type == FAKE_TM_IRB) {
509                 struct tm_scsw *scsw = &irb->scsw.tm;
510                 scsw->x = 1;
511                 scsw->cc = 1;
512                 scsw->fctl = SCSW_FCTL_START_FUNC;
513                 scsw->actl = SCSW_ACTL_START_PEND;
514                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
515         }
516 }
517
518 void ccw_device_verify_done(struct ccw_device *cdev, int err)
519 {
520         struct subchannel *sch;
521
522         sch = to_subchannel(cdev->dev.parent);
523         /* Update schib - pom may have changed. */
524         if (cio_update_schib(sch)) {
525                 err = -ENODEV;
526                 goto callback;
527         }
528         /* Update lpm with verified path mask. */
529         sch->lpm = sch->vpm;
530         /* Repeat path verification? */
531         if (cdev->private->flags.doverify) {
532                 ccw_device_verify_start(cdev);
533                 return;
534         }
535 callback:
536         switch (err) {
537         case 0:
538                 ccw_device_done(cdev, DEV_STATE_ONLINE);
539                 /* Deliver fake irb to device driver, if needed. */
540                 if (cdev->private->flags.fake_irb) {
541                         create_fake_irb(&cdev->private->irb,
542                                         cdev->private->flags.fake_irb);
543                         cdev->private->flags.fake_irb = 0;
544                         if (cdev->handler)
545                                 cdev->handler(cdev, cdev->private->intparm,
546                                               &cdev->private->irb);
547                         memset(&cdev->private->irb, 0, sizeof(struct irb));
548                 }
549                 ccw_device_report_path_events(cdev);
550                 break;
551         case -ETIME:
552         case -EUSERS:
553                 /* Reset oper notify indication after verify error. */
554                 cdev->private->flags.donotify = 0;
555                 ccw_device_done(cdev, DEV_STATE_BOXED);
556                 break;
557         case -EACCES:
558                 /* Reset oper notify indication after verify error. */
559                 cdev->private->flags.donotify = 0;
560                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
561                 break;
562         default:
563                 /* Reset oper notify indication after verify error. */
564                 cdev->private->flags.donotify = 0;
565                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
566                 break;
567         }
568         ccw_device_reset_path_events(cdev);
569 }
570
571 /*
572  * Get device online.
573  */
574 int
575 ccw_device_online(struct ccw_device *cdev)
576 {
577         struct subchannel *sch;
578         int ret;
579
580         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
581             (cdev->private->state != DEV_STATE_BOXED))
582                 return -EINVAL;
583         sch = to_subchannel(cdev->dev.parent);
584         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
585         if (ret != 0) {
586                 /* Couldn't enable the subchannel for i/o. Sick device. */
587                 if (ret == -ENODEV)
588                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
589                 return ret;
590         }
591         /* Start initial path verification. */
592         cdev->private->state = DEV_STATE_VERIFY;
593         ccw_device_verify_start(cdev);
594         return 0;
595 }
596
597 void
598 ccw_device_disband_done(struct ccw_device *cdev, int err)
599 {
600         switch (err) {
601         case 0:
602                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
603                 break;
604         case -ETIME:
605                 ccw_device_done(cdev, DEV_STATE_BOXED);
606                 break;
607         default:
608                 cdev->private->flags.donotify = 0;
609                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
610                 break;
611         }
612 }
613
614 /*
615  * Shutdown device.
616  */
617 int
618 ccw_device_offline(struct ccw_device *cdev)
619 {
620         struct subchannel *sch;
621
622         /* Allow ccw_device_offline while disconnected. */
623         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
624             cdev->private->state == DEV_STATE_NOT_OPER) {
625                 cdev->private->flags.donotify = 0;
626                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
627                 return 0;
628         }
629         if (cdev->private->state == DEV_STATE_BOXED) {
630                 ccw_device_done(cdev, DEV_STATE_BOXED);
631                 return 0;
632         }
633         if (ccw_device_is_orphan(cdev)) {
634                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
635                 return 0;
636         }
637         sch = to_subchannel(cdev->dev.parent);
638         if (cio_update_schib(sch))
639                 return -ENODEV;
640         if (scsw_actl(&sch->schib.scsw) != 0)
641                 return -EBUSY;
642         if (cdev->private->state != DEV_STATE_ONLINE)
643                 return -EINVAL;
644         /* Are we doing path grouping? */
645         if (!cdev->private->flags.pgroup) {
646                 /* No, set state offline immediately. */
647                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
648                 return 0;
649         }
650         /* Start Set Path Group commands. */
651         cdev->private->state = DEV_STATE_DISBAND_PGID;
652         ccw_device_disband_start(cdev);
653         return 0;
654 }
655
656 /*
657  * Handle not operational event in non-special state.
658  */
659 static void ccw_device_generic_notoper(struct ccw_device *cdev,
660                                        enum dev_event dev_event)
661 {
662         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
663                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
664         else
665                 ccw_device_set_disconnected(cdev);
666 }
667
668 /*
669  * Handle path verification event in offline state.
670  */
671 static void ccw_device_offline_verify(struct ccw_device *cdev,
672                                       enum dev_event dev_event)
673 {
674         struct subchannel *sch = to_subchannel(cdev->dev.parent);
675
676         css_schedule_eval(sch->schid);
677 }
678
679 /*
680  * Handle path verification event.
681  */
682 static void
683 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
684 {
685         struct subchannel *sch;
686
687         if (cdev->private->state == DEV_STATE_W4SENSE) {
688                 cdev->private->flags.doverify = 1;
689                 return;
690         }
691         sch = to_subchannel(cdev->dev.parent);
692         /*
693          * Since we might not just be coming from an interrupt from the
694          * subchannel we have to update the schib.
695          */
696         if (cio_update_schib(sch)) {
697                 ccw_device_verify_done(cdev, -ENODEV);
698                 return;
699         }
700
701         if (scsw_actl(&sch->schib.scsw) != 0 ||
702             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
703             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
704                 /*
705                  * No final status yet or final status not yet delivered
706                  * to the device driver. Can't do path verification now,
707                  * delay until final status was delivered.
708                  */
709                 cdev->private->flags.doverify = 1;
710                 return;
711         }
712         /* Device is idle, we can do the path verification. */
713         cdev->private->state = DEV_STATE_VERIFY;
714         ccw_device_verify_start(cdev);
715 }
716
717 /*
718  * Handle path verification event in boxed state.
719  */
720 static void ccw_device_boxed_verify(struct ccw_device *cdev,
721                                     enum dev_event dev_event)
722 {
723         struct subchannel *sch = to_subchannel(cdev->dev.parent);
724
725         if (cdev->online) {
726                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
727                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
728                 else
729                         ccw_device_online_verify(cdev, dev_event);
730         } else
731                 css_schedule_eval(sch->schid);
732 }
733
734 /*
735  * Got an interrupt for a normal io (state online).
736  */
737 static void
738 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
739 {
740         struct irb *irb;
741         int is_cmd;
742
743         irb = (struct irb *)&S390_lowcore.irb;
744         is_cmd = !scsw_is_tm(&irb->scsw);
745         /* Check for unsolicited interrupt. */
746         if (!scsw_is_solicited(&irb->scsw)) {
747                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
748                     !irb->esw.esw0.erw.cons) {
749                         /* Unit check but no sense data. Need basic sense. */
750                         if (ccw_device_do_sense(cdev, irb) != 0)
751                                 goto call_handler_unsol;
752                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
753                         cdev->private->state = DEV_STATE_W4SENSE;
754                         cdev->private->intparm = 0;
755                         return;
756                 }
757 call_handler_unsol:
758                 if (cdev->handler)
759                         cdev->handler (cdev, 0, irb);
760                 if (cdev->private->flags.doverify)
761                         ccw_device_online_verify(cdev, 0);
762                 return;
763         }
764         /* Accumulate status and find out if a basic sense is needed. */
765         ccw_device_accumulate_irb(cdev, irb);
766         if (is_cmd && cdev->private->flags.dosense) {
767                 if (ccw_device_do_sense(cdev, irb) == 0) {
768                         cdev->private->state = DEV_STATE_W4SENSE;
769                 }
770                 return;
771         }
772         /* Call the handler. */
773         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
774                 /* Start delayed path verification. */
775                 ccw_device_online_verify(cdev, 0);
776 }
777
778 /*
779  * Got an timeout in online state.
780  */
781 static void
782 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
783 {
784         int ret;
785
786         ccw_device_set_timeout(cdev, 0);
787         cdev->private->iretry = 255;
788         ret = ccw_device_cancel_halt_clear(cdev);
789         if (ret == -EBUSY) {
790                 ccw_device_set_timeout(cdev, 3*HZ);
791                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
792                 return;
793         }
794         if (ret)
795                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
796         else if (cdev->handler)
797                 cdev->handler(cdev, cdev->private->intparm,
798                               ERR_PTR(-ETIMEDOUT));
799 }
800
801 /*
802  * Got an interrupt for a basic sense.
803  */
804 static void
805 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
806 {
807         struct irb *irb;
808
809         irb = (struct irb *)&S390_lowcore.irb;
810         /* Check for unsolicited interrupt. */
811         if (scsw_stctl(&irb->scsw) ==
812             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
813                 if (scsw_cc(&irb->scsw) == 1)
814                         /* Basic sense hasn't started. Try again. */
815                         ccw_device_do_sense(cdev, irb);
816                 else {
817                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
818                                       "interrupt during w4sense...\n",
819                                       cdev->private->dev_id.ssid,
820                                       cdev->private->dev_id.devno);
821                         if (cdev->handler)
822                                 cdev->handler (cdev, 0, irb);
823                 }
824                 return;
825         }
826         /*
827          * Check if a halt or clear has been issued in the meanwhile. If yes,
828          * only deliver the halt/clear interrupt to the device driver as if it
829          * had killed the original request.
830          */
831         if (scsw_fctl(&irb->scsw) &
832             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
833                 cdev->private->flags.dosense = 0;
834                 memset(&cdev->private->irb, 0, sizeof(struct irb));
835                 ccw_device_accumulate_irb(cdev, irb);
836                 goto call_handler;
837         }
838         /* Add basic sense info to irb. */
839         ccw_device_accumulate_basic_sense(cdev, irb);
840         if (cdev->private->flags.dosense) {
841                 /* Another basic sense is needed. */
842                 ccw_device_do_sense(cdev, irb);
843                 return;
844         }
845 call_handler:
846         cdev->private->state = DEV_STATE_ONLINE;
847         /* In case sensing interfered with setting the device online */
848         wake_up(&cdev->private->wait_q);
849         /* Call the handler. */
850         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
851                 /* Start delayed path verification. */
852                 ccw_device_online_verify(cdev, 0);
853 }
854
855 static void
856 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
857 {
858         ccw_device_set_timeout(cdev, 0);
859         /* Start delayed path verification. */
860         ccw_device_online_verify(cdev, 0);
861         /* OK, i/o is dead now. Call interrupt handler. */
862         if (cdev->handler)
863                 cdev->handler(cdev, cdev->private->intparm,
864                               ERR_PTR(-EIO));
865 }
866
867 static void
868 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
869 {
870         int ret;
871
872         ret = ccw_device_cancel_halt_clear(cdev);
873         if (ret == -EBUSY) {
874                 ccw_device_set_timeout(cdev, 3*HZ);
875                 return;
876         }
877         /* Start delayed path verification. */
878         ccw_device_online_verify(cdev, 0);
879         if (cdev->handler)
880                 cdev->handler(cdev, cdev->private->intparm,
881                               ERR_PTR(-EIO));
882 }
883
884 void ccw_device_kill_io(struct ccw_device *cdev)
885 {
886         int ret;
887
888         cdev->private->iretry = 255;
889         ret = ccw_device_cancel_halt_clear(cdev);
890         if (ret == -EBUSY) {
891                 ccw_device_set_timeout(cdev, 3*HZ);
892                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
893                 return;
894         }
895         /* Start delayed path verification. */
896         ccw_device_online_verify(cdev, 0);
897         if (cdev->handler)
898                 cdev->handler(cdev, cdev->private->intparm,
899                               ERR_PTR(-EIO));
900 }
901
902 static void
903 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
904 {
905         /* Start verification after current task finished. */
906         cdev->private->flags.doverify = 1;
907 }
908
909 static void
910 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
911 {
912         struct subchannel *sch;
913
914         sch = to_subchannel(cdev->dev.parent);
915         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
916                 /* Couldn't enable the subchannel for i/o. Sick device. */
917                 return;
918         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
919         ccw_device_sense_id_start(cdev);
920 }
921
922 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
923 {
924         struct subchannel *sch;
925
926         if (cdev->private->state != DEV_STATE_DISCONNECTED)
927                 return;
928
929         sch = to_subchannel(cdev->dev.parent);
930         /* Update some values. */
931         if (cio_update_schib(sch))
932                 return;
933         /*
934          * The pim, pam, pom values may not be accurate, but they are the best
935          * we have before performing device selection :/
936          */
937         sch->lpm = sch->schib.pmcw.pam & sch->opm;
938         /*
939          * Use the initial configuration since we can't be shure that the old
940          * paths are valid.
941          */
942         io_subchannel_init_config(sch);
943         if (cio_commit_config(sch))
944                 return;
945
946         /* We should also udate ssd info, but this has to wait. */
947         /* Check if this is another device which appeared on the same sch. */
948         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
949                 css_schedule_eval(sch->schid);
950         else
951                 ccw_device_start_id(cdev, 0);
952 }
953
954 static void ccw_device_disabled_irq(struct ccw_device *cdev,
955                                     enum dev_event dev_event)
956 {
957         struct subchannel *sch;
958
959         sch = to_subchannel(cdev->dev.parent);
960         /*
961          * An interrupt in a disabled state means a previous disable was not
962          * successful - should not happen, but we try to disable again.
963          */
964         cio_disable_subchannel(sch);
965 }
966
967 static void
968 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
969 {
970         retry_set_schib(cdev);
971         cdev->private->state = DEV_STATE_ONLINE;
972         dev_fsm_event(cdev, dev_event);
973 }
974
975 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
976                                        enum dev_event dev_event)
977 {
978         cmf_retry_copy_block(cdev);
979         cdev->private->state = DEV_STATE_ONLINE;
980         dev_fsm_event(cdev, dev_event);
981 }
982
983 static void
984 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
985 {
986         ccw_device_set_timeout(cdev, 0);
987         cdev->private->state = DEV_STATE_NOT_OPER;
988         wake_up(&cdev->private->wait_q);
989 }
990
991 static void
992 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
993 {
994         int ret;
995
996         ret = ccw_device_cancel_halt_clear(cdev);
997         if (ret == -EBUSY) {
998                 ccw_device_set_timeout(cdev, HZ/10);
999         } else {
1000                 cdev->private->state = DEV_STATE_NOT_OPER;
1001                 wake_up(&cdev->private->wait_q);
1002         }
1003 }
1004
1005 /*
1006  * No operation action. This is used e.g. to ignore a timeout event in
1007  * state offline.
1008  */
1009 static void
1010 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1011 {
1012 }
1013
1014 /*
1015  * device statemachine
1016  */
1017 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1018         [DEV_STATE_NOT_OPER] = {
1019                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1020                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1021                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1022                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1023         },
1024         [DEV_STATE_SENSE_PGID] = {
1025                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1026                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1027                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1028                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1029         },
1030         [DEV_STATE_SENSE_ID] = {
1031                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1032                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1033                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1034                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1035         },
1036         [DEV_STATE_OFFLINE] = {
1037                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1038                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1039                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1040                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1041         },
1042         [DEV_STATE_VERIFY] = {
1043                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1044                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1045                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1046                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1047         },
1048         [DEV_STATE_ONLINE] = {
1049                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1050                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1051                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1052                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1053         },
1054         [DEV_STATE_W4SENSE] = {
1055                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1056                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1057                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1058                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1059         },
1060         [DEV_STATE_DISBAND_PGID] = {
1061                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1062                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1063                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1064                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1065         },
1066         [DEV_STATE_BOXED] = {
1067                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1068                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1069                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1070                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1071         },
1072         /* states to wait for i/o completion before doing something */
1073         [DEV_STATE_TIMEOUT_KILL] = {
1074                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1075                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1076                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1077                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1078         },
1079         [DEV_STATE_QUIESCE] = {
1080                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1081                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1082                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1083                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1084         },
1085         /* special states for devices gone not operational */
1086         [DEV_STATE_DISCONNECTED] = {
1087                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1088                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1089                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1090                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1091         },
1092         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1093                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1094                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1095                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1096                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1097         },
1098         [DEV_STATE_CMFCHANGE] = {
1099                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1100                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1101                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1102                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1103         },
1104         [DEV_STATE_CMFUPDATE] = {
1105                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1106                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1107                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1108                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1109         },
1110         [DEV_STATE_STEAL_LOCK] = {
1111                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1112                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1113                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1114                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1115         },
1116 };
1117
1118 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);