Merge branches 'core/futexes', 'core/locking', 'core/rcu' and 'linus' into core/urgent
[linux-2.6] / 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(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         panic("Can't stop i/o on subchannel.\n");
178 }
179
180 static int
181 ccw_device_handle_oper(struct ccw_device *cdev)
182 {
183         struct subchannel *sch;
184
185         sch = to_subchannel(cdev->dev.parent);
186         cdev->private->flags.recog_done = 1;
187         /*
188          * Check if cu type and device type still match. If
189          * not, it is certainly another device and we have to
190          * de- and re-register.
191          */
192         if (cdev->id.cu_type != cdev->private->senseid.cu_type ||
193             cdev->id.cu_model != cdev->private->senseid.cu_model ||
194             cdev->id.dev_type != cdev->private->senseid.dev_type ||
195             cdev->id.dev_model != cdev->private->senseid.dev_model) {
196                 PREPARE_WORK(&cdev->private->kick_work,
197                              ccw_device_do_unreg_rereg);
198                 queue_work(ccw_device_work, &cdev->private->kick_work);
199                 return 0;
200         }
201         cdev->private->flags.donotify = 1;
202         return 1;
203 }
204
205 /*
206  * The machine won't give us any notification by machine check if a chpid has
207  * been varied online on the SE so we have to find out by magic (i. e. driving
208  * the channel subsystem to device selection and updating our path masks).
209  */
210 static void
211 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
212 {
213         int mask, i;
214         struct chp_id chpid;
215
216         chp_id_init(&chpid);
217         for (i = 0; i<8; i++) {
218                 mask = 0x80 >> i;
219                 if (!(sch->lpm & mask))
220                         continue;
221                 if (old_lpm & mask)
222                         continue;
223                 chpid.id = sch->schib.pmcw.chpid[i];
224                 if (!chp_is_registered(chpid))
225                         css_schedule_eval_all();
226         }
227 }
228
229 /*
230  * Stop device recognition.
231  */
232 static void
233 ccw_device_recog_done(struct ccw_device *cdev, int state)
234 {
235         struct subchannel *sch;
236         int notify, old_lpm, same_dev;
237
238         sch = to_subchannel(cdev->dev.parent);
239
240         ccw_device_set_timeout(cdev, 0);
241         cio_disable_subchannel(sch);
242         /*
243          * Now that we tried recognition, we have performed device selection
244          * through ssch() and the path information is up to date.
245          */
246         old_lpm = sch->lpm;
247
248         /* Check since device may again have become not operational. */
249         if (cio_update_schib(sch))
250                 state = DEV_STATE_NOT_OPER;
251         else
252                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
253
254         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
255                 /* Force reprobe on all chpids. */
256                 old_lpm = 0;
257         if (sch->lpm != old_lpm)
258                 __recover_lost_chpids(sch, old_lpm);
259         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
260                 if (state == DEV_STATE_NOT_OPER) {
261                         cdev->private->flags.recog_done = 1;
262                         cdev->private->state = DEV_STATE_DISCONNECTED;
263                         return;
264                 }
265                 /* Boxed devices don't need extra treatment. */
266         }
267         notify = 0;
268         same_dev = 0; /* Keep the compiler quiet... */
269         switch (state) {
270         case DEV_STATE_NOT_OPER:
271                 CIO_MSG_EVENT(2, "SenseID : unknown device %04x on "
272                               "subchannel 0.%x.%04x\n",
273                               cdev->private->dev_id.devno,
274                               sch->schid.ssid, sch->schid.sch_no);
275                 break;
276         case DEV_STATE_OFFLINE:
277                 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
278                         same_dev = ccw_device_handle_oper(cdev);
279                         notify = 1;
280                 }
281                 /* fill out sense information */
282                 memset(&cdev->id, 0, sizeof(cdev->id));
283                 cdev->id.cu_type   = cdev->private->senseid.cu_type;
284                 cdev->id.cu_model  = cdev->private->senseid.cu_model;
285                 cdev->id.dev_type  = cdev->private->senseid.dev_type;
286                 cdev->id.dev_model = cdev->private->senseid.dev_model;
287                 if (notify) {
288                         cdev->private->state = DEV_STATE_OFFLINE;
289                         if (same_dev) {
290                                 /* Get device online again. */
291                                 ccw_device_online(cdev);
292                                 wake_up(&cdev->private->wait_q);
293                         }
294                         return;
295                 }
296                 /* Issue device info message. */
297                 CIO_MSG_EVENT(4, "SenseID : device 0.%x.%04x reports: "
298                               "CU  Type/Mod = %04X/%02X, Dev Type/Mod = "
299                               "%04X/%02X\n",
300                               cdev->private->dev_id.ssid,
301                               cdev->private->dev_id.devno,
302                               cdev->id.cu_type, cdev->id.cu_model,
303                               cdev->id.dev_type, cdev->id.dev_model);
304                 break;
305         case DEV_STATE_BOXED:
306                 CIO_MSG_EVENT(0, "SenseID : boxed device %04x on "
307                               " subchannel 0.%x.%04x\n",
308                               cdev->private->dev_id.devno,
309                               sch->schid.ssid, sch->schid.sch_no);
310                 break;
311         }
312         cdev->private->state = state;
313         io_subchannel_recog_done(cdev);
314         if (state != DEV_STATE_NOT_OPER)
315                 wake_up(&cdev->private->wait_q);
316 }
317
318 /*
319  * Function called from device_id.c after sense id has completed.
320  */
321 void
322 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
323 {
324         switch (err) {
325         case 0:
326                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
327                 break;
328         case -ETIME:            /* Sense id stopped by timeout. */
329                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
330                 break;
331         default:
332                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
333                 break;
334         }
335 }
336
337 int ccw_device_notify(struct ccw_device *cdev, int event)
338 {
339         if (!cdev->drv)
340                 return 0;
341         if (!cdev->online)
342                 return 0;
343         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
344                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
345                       event);
346         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
347 }
348
349 static void cmf_reenable_delayed(struct work_struct *work)
350 {
351         struct ccw_device_private *priv;
352         struct ccw_device *cdev;
353
354         priv = container_of(work, struct ccw_device_private, kick_work);
355         cdev = priv->cdev;
356         cmf_reenable(cdev);
357 }
358
359 static void ccw_device_oper_notify(struct ccw_device *cdev)
360 {
361         if (ccw_device_notify(cdev, CIO_OPER)) {
362                 /* Reenable channel measurements, if needed. */
363                 PREPARE_WORK(&cdev->private->kick_work, cmf_reenable_delayed);
364                 queue_work(ccw_device_work, &cdev->private->kick_work);
365                 return;
366         }
367         /* Driver doesn't want device back. */
368         ccw_device_set_notoper(cdev);
369         PREPARE_WORK(&cdev->private->kick_work, ccw_device_do_unreg_rereg);
370         queue_work(ccw_device_work, &cdev->private->kick_work);
371 }
372
373 /*
374  * Finished with online/offline processing.
375  */
376 static void
377 ccw_device_done(struct ccw_device *cdev, int state)
378 {
379         struct subchannel *sch;
380
381         sch = to_subchannel(cdev->dev.parent);
382
383         ccw_device_set_timeout(cdev, 0);
384
385         if (state != DEV_STATE_ONLINE)
386                 cio_disable_subchannel(sch);
387
388         /* Reset device status. */
389         memset(&cdev->private->irb, 0, sizeof(struct irb));
390
391         cdev->private->state = state;
392
393
394         if (state == DEV_STATE_BOXED)
395                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
396                               cdev->private->dev_id.devno, sch->schid.sch_no);
397
398         if (cdev->private->flags.donotify) {
399                 cdev->private->flags.donotify = 0;
400                 ccw_device_oper_notify(cdev);
401         }
402         wake_up(&cdev->private->wait_q);
403 }
404
405 static int cmp_pgid(struct pgid *p1, struct pgid *p2)
406 {
407         char *c1;
408         char *c2;
409
410         c1 = (char *)p1;
411         c2 = (char *)p2;
412
413         return memcmp(c1 + 1, c2 + 1, sizeof(struct pgid) - 1);
414 }
415
416 static void __ccw_device_get_common_pgid(struct ccw_device *cdev)
417 {
418         int i;
419         int last;
420
421         last = 0;
422         for (i = 0; i < 8; i++) {
423                 if (cdev->private->pgid[i].inf.ps.state1 == SNID_STATE1_RESET)
424                         /* No PGID yet */
425                         continue;
426                 if (cdev->private->pgid[last].inf.ps.state1 ==
427                     SNID_STATE1_RESET) {
428                         /* First non-zero PGID */
429                         last = i;
430                         continue;
431                 }
432                 if (cmp_pgid(&cdev->private->pgid[i],
433                              &cdev->private->pgid[last]) == 0)
434                         /* Non-conflicting PGIDs */
435                         continue;
436
437                 /* PGID mismatch, can't pathgroup. */
438                 CIO_MSG_EVENT(0, "SNID - pgid mismatch for device "
439                               "0.%x.%04x, can't pathgroup\n",
440                               cdev->private->dev_id.ssid,
441                               cdev->private->dev_id.devno);
442                 cdev->private->options.pgroup = 0;
443                 return;
444         }
445         if (cdev->private->pgid[last].inf.ps.state1 ==
446             SNID_STATE1_RESET)
447                 /* No previous pgid found */
448                 memcpy(&cdev->private->pgid[0],
449                        &channel_subsystems[0]->global_pgid,
450                        sizeof(struct pgid));
451         else
452                 /* Use existing pgid */
453                 memcpy(&cdev->private->pgid[0], &cdev->private->pgid[last],
454                        sizeof(struct pgid));
455 }
456
457 /*
458  * Function called from device_pgid.c after sense path ground has completed.
459  */
460 void
461 ccw_device_sense_pgid_done(struct ccw_device *cdev, int err)
462 {
463         struct subchannel *sch;
464
465         sch = to_subchannel(cdev->dev.parent);
466         switch (err) {
467         case -EOPNOTSUPP: /* path grouping not supported, use nop instead. */
468                 cdev->private->options.pgroup = 0;
469                 break;
470         case 0: /* success */
471         case -EACCES: /* partial success, some paths not operational */
472                 /* Check if all pgids are equal or 0. */
473                 __ccw_device_get_common_pgid(cdev);
474                 break;
475         case -ETIME:            /* Sense path group id stopped by timeout. */
476         case -EUSERS:           /* device is reserved for someone else. */
477                 ccw_device_done(cdev, DEV_STATE_BOXED);
478                 return;
479         default:
480                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
481                 return;
482         }
483         /* Start Path Group verification. */
484         cdev->private->state = DEV_STATE_VERIFY;
485         cdev->private->flags.doverify = 0;
486         ccw_device_verify_start(cdev);
487 }
488
489 /*
490  * Start device recognition.
491  */
492 int
493 ccw_device_recognition(struct ccw_device *cdev)
494 {
495         struct subchannel *sch;
496         int ret;
497
498         if ((cdev->private->state != DEV_STATE_NOT_OPER) &&
499             (cdev->private->state != DEV_STATE_BOXED))
500                 return -EINVAL;
501         sch = to_subchannel(cdev->dev.parent);
502         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
503         if (ret != 0)
504                 /* Couldn't enable the subchannel for i/o. Sick device. */
505                 return ret;
506
507         /* After 60s the device recognition is considered to have failed. */
508         ccw_device_set_timeout(cdev, 60*HZ);
509
510         /*
511          * We used to start here with a sense pgid to find out whether a device
512          * is locked by someone else. Unfortunately, the sense pgid command
513          * code has other meanings on devices predating the path grouping
514          * algorithm, so we start with sense id and box the device after an
515          * timeout (or if sense pgid during path verification detects the device
516          * is locked, as may happen on newer devices).
517          */
518         cdev->private->flags.recog_done = 0;
519         cdev->private->state = DEV_STATE_SENSE_ID;
520         ccw_device_sense_id_start(cdev);
521         return 0;
522 }
523
524 /*
525  * Handle timeout in device recognition.
526  */
527 static void
528 ccw_device_recog_timeout(struct ccw_device *cdev, enum dev_event dev_event)
529 {
530         int ret;
531
532         ret = ccw_device_cancel_halt_clear(cdev);
533         switch (ret) {
534         case 0:
535                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
536                 break;
537         case -ENODEV:
538                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
539                 break;
540         default:
541                 ccw_device_set_timeout(cdev, 3*HZ);
542         }
543 }
544
545
546 void
547 ccw_device_verify_done(struct ccw_device *cdev, int err)
548 {
549         struct subchannel *sch;
550
551         sch = to_subchannel(cdev->dev.parent);
552         /* Update schib - pom may have changed. */
553         if (cio_update_schib(sch)) {
554                 cdev->private->flags.donotify = 0;
555                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
556                 return;
557         }
558         /* Update lpm with verified path mask. */
559         sch->lpm = sch->vpm;
560         /* Repeat path verification? */
561         if (cdev->private->flags.doverify) {
562                 cdev->private->flags.doverify = 0;
563                 ccw_device_verify_start(cdev);
564                 return;
565         }
566         switch (err) {
567         case -EOPNOTSUPP: /* path grouping not supported, just set online. */
568                 cdev->private->options.pgroup = 0;
569         case 0:
570                 ccw_device_done(cdev, DEV_STATE_ONLINE);
571                 /* Deliver fake irb to device driver, if needed. */
572                 if (cdev->private->flags.fake_irb) {
573                         memset(&cdev->private->irb, 0, sizeof(struct irb));
574                         cdev->private->irb.scsw.cmd.cc = 1;
575                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
576                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
577                         cdev->private->irb.scsw.cmd.stctl =
578                                 SCSW_STCTL_STATUS_PEND;
579                         cdev->private->flags.fake_irb = 0;
580                         if (cdev->handler)
581                                 cdev->handler(cdev, cdev->private->intparm,
582                                               &cdev->private->irb);
583                         memset(&cdev->private->irb, 0, sizeof(struct irb));
584                 }
585                 break;
586         case -ETIME:
587                 /* Reset oper notify indication after verify error. */
588                 cdev->private->flags.donotify = 0;
589                 ccw_device_done(cdev, DEV_STATE_BOXED);
590                 break;
591         default:
592                 /* Reset oper notify indication after verify error. */
593                 cdev->private->flags.donotify = 0;
594                 if (cdev->online) {
595                         ccw_device_set_timeout(cdev, 0);
596                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
597                 } else
598                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
599                 break;
600         }
601 }
602
603 /*
604  * Get device online.
605  */
606 int
607 ccw_device_online(struct ccw_device *cdev)
608 {
609         struct subchannel *sch;
610         int ret;
611
612         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
613             (cdev->private->state != DEV_STATE_BOXED))
614                 return -EINVAL;
615         sch = to_subchannel(cdev->dev.parent);
616         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
617         if (ret != 0) {
618                 /* Couldn't enable the subchannel for i/o. Sick device. */
619                 if (ret == -ENODEV)
620                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
621                 return ret;
622         }
623         /* Do we want to do path grouping? */
624         if (!cdev->private->options.pgroup) {
625                 /* Start initial path verification. */
626                 cdev->private->state = DEV_STATE_VERIFY;
627                 cdev->private->flags.doverify = 0;
628                 ccw_device_verify_start(cdev);
629                 return 0;
630         }
631         /* Do a SensePGID first. */
632         cdev->private->state = DEV_STATE_SENSE_PGID;
633         ccw_device_sense_pgid_start(cdev);
634         return 0;
635 }
636
637 void
638 ccw_device_disband_done(struct ccw_device *cdev, int err)
639 {
640         switch (err) {
641         case 0:
642                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
643                 break;
644         case -ETIME:
645                 ccw_device_done(cdev, DEV_STATE_BOXED);
646                 break;
647         default:
648                 cdev->private->flags.donotify = 0;
649                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
650                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
651                 break;
652         }
653 }
654
655 /*
656  * Shutdown device.
657  */
658 int
659 ccw_device_offline(struct ccw_device *cdev)
660 {
661         struct subchannel *sch;
662
663         /* Allow ccw_device_offline while disconnected. */
664         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
665             cdev->private->state == DEV_STATE_NOT_OPER) {
666                 cdev->private->flags.donotify = 0;
667                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
668                 return 0;
669         }
670         if (ccw_device_is_orphan(cdev)) {
671                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
672                 return 0;
673         }
674         sch = to_subchannel(cdev->dev.parent);
675         if (cio_update_schib(sch))
676                 return -ENODEV;
677         if (scsw_actl(&sch->schib.scsw) != 0)
678                 return -EBUSY;
679         if (cdev->private->state != DEV_STATE_ONLINE)
680                 return -EINVAL;
681         /* Are we doing path grouping? */
682         if (!cdev->private->options.pgroup) {
683                 /* No, set state offline immediately. */
684                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
685                 return 0;
686         }
687         /* Start Set Path Group commands. */
688         cdev->private->state = DEV_STATE_DISBAND_PGID;
689         ccw_device_disband_start(cdev);
690         return 0;
691 }
692
693 /*
694  * Handle timeout in device online/offline process.
695  */
696 static void
697 ccw_device_onoff_timeout(struct ccw_device *cdev, enum dev_event dev_event)
698 {
699         int ret;
700
701         ret = ccw_device_cancel_halt_clear(cdev);
702         switch (ret) {
703         case 0:
704                 ccw_device_done(cdev, DEV_STATE_BOXED);
705                 break;
706         case -ENODEV:
707                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
708                 break;
709         default:
710                 ccw_device_set_timeout(cdev, 3*HZ);
711         }
712 }
713
714 /*
715  * Handle not oper event in device recognition.
716  */
717 static void
718 ccw_device_recog_notoper(struct ccw_device *cdev, enum dev_event dev_event)
719 {
720         ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
721 }
722
723 /*
724  * Handle not operational event in non-special state.
725  */
726 static void ccw_device_generic_notoper(struct ccw_device *cdev,
727                                        enum dev_event dev_event)
728 {
729         struct subchannel *sch;
730
731         cdev->private->state = DEV_STATE_NOT_OPER;
732         sch = to_subchannel(cdev->dev.parent);
733         css_schedule_eval(sch->schid);
734 }
735
736 /*
737  * Handle path verification event.
738  */
739 static void
740 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
741 {
742         struct subchannel *sch;
743
744         if (cdev->private->state == DEV_STATE_W4SENSE) {
745                 cdev->private->flags.doverify = 1;
746                 return;
747         }
748         sch = to_subchannel(cdev->dev.parent);
749         /*
750          * Since we might not just be coming from an interrupt from the
751          * subchannel we have to update the schib.
752          */
753         if (cio_update_schib(sch)) {
754                 ccw_device_verify_done(cdev, -ENODEV);
755                 return;
756         }
757
758         if (scsw_actl(&sch->schib.scsw) != 0 ||
759             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
760             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
761                 /*
762                  * No final status yet or final status not yet delivered
763                  * to the device driver. Can't do path verfication now,
764                  * delay until final status was delivered.
765                  */
766                 cdev->private->flags.doverify = 1;
767                 return;
768         }
769         /* Device is idle, we can do the path verification. */
770         cdev->private->state = DEV_STATE_VERIFY;
771         cdev->private->flags.doverify = 0;
772         ccw_device_verify_start(cdev);
773 }
774
775 /*
776  * Got an interrupt for a normal io (state online).
777  */
778 static void
779 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
780 {
781         struct irb *irb;
782         int is_cmd;
783
784         irb = (struct irb *) __LC_IRB;
785         is_cmd = !scsw_is_tm(&irb->scsw);
786         /* Check for unsolicited interrupt. */
787         if (!scsw_is_solicited(&irb->scsw)) {
788                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
789                     !irb->esw.esw0.erw.cons) {
790                         /* Unit check but no sense data. Need basic sense. */
791                         if (ccw_device_do_sense(cdev, irb) != 0)
792                                 goto call_handler_unsol;
793                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
794                         cdev->private->state = DEV_STATE_W4SENSE;
795                         cdev->private->intparm = 0;
796                         return;
797                 }
798 call_handler_unsol:
799                 if (cdev->handler)
800                         cdev->handler (cdev, 0, irb);
801                 if (cdev->private->flags.doverify)
802                         ccw_device_online_verify(cdev, 0);
803                 return;
804         }
805         /* Accumulate status and find out if a basic sense is needed. */
806         ccw_device_accumulate_irb(cdev, irb);
807         if (is_cmd && cdev->private->flags.dosense) {
808                 if (ccw_device_do_sense(cdev, irb) == 0) {
809                         cdev->private->state = DEV_STATE_W4SENSE;
810                 }
811                 return;
812         }
813         /* Call the handler. */
814         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
815                 /* Start delayed path verification. */
816                 ccw_device_online_verify(cdev, 0);
817 }
818
819 /*
820  * Got an timeout in online state.
821  */
822 static void
823 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
824 {
825         int ret;
826
827         ccw_device_set_timeout(cdev, 0);
828         ret = ccw_device_cancel_halt_clear(cdev);
829         if (ret == -EBUSY) {
830                 ccw_device_set_timeout(cdev, 3*HZ);
831                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
832                 return;
833         }
834         if (ret == -ENODEV)
835                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
836         else if (cdev->handler)
837                 cdev->handler(cdev, cdev->private->intparm,
838                               ERR_PTR(-ETIMEDOUT));
839 }
840
841 /*
842  * Got an interrupt for a basic sense.
843  */
844 static void
845 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
846 {
847         struct irb *irb;
848
849         irb = (struct irb *) __LC_IRB;
850         /* Check for unsolicited interrupt. */
851         if (scsw_stctl(&irb->scsw) ==
852             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
853                 if (scsw_cc(&irb->scsw) == 1)
854                         /* Basic sense hasn't started. Try again. */
855                         ccw_device_do_sense(cdev, irb);
856                 else {
857                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
858                                       "interrupt during w4sense...\n",
859                                       cdev->private->dev_id.ssid,
860                                       cdev->private->dev_id.devno);
861                         if (cdev->handler)
862                                 cdev->handler (cdev, 0, irb);
863                 }
864                 return;
865         }
866         /*
867          * Check if a halt or clear has been issued in the meanwhile. If yes,
868          * only deliver the halt/clear interrupt to the device driver as if it
869          * had killed the original request.
870          */
871         if (scsw_fctl(&irb->scsw) &
872             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
873                 /* Retry Basic Sense if requested. */
874                 if (cdev->private->flags.intretry) {
875                         cdev->private->flags.intretry = 0;
876                         ccw_device_do_sense(cdev, irb);
877                         return;
878                 }
879                 cdev->private->flags.dosense = 0;
880                 memset(&cdev->private->irb, 0, sizeof(struct irb));
881                 ccw_device_accumulate_irb(cdev, irb);
882                 goto call_handler;
883         }
884         /* Add basic sense info to irb. */
885         ccw_device_accumulate_basic_sense(cdev, irb);
886         if (cdev->private->flags.dosense) {
887                 /* Another basic sense is needed. */
888                 ccw_device_do_sense(cdev, irb);
889                 return;
890         }
891 call_handler:
892         cdev->private->state = DEV_STATE_ONLINE;
893         /* Call the handler. */
894         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
895                 /* Start delayed path verification. */
896                 ccw_device_online_verify(cdev, 0);
897 }
898
899 static void
900 ccw_device_clear_verify(struct ccw_device *cdev, enum dev_event dev_event)
901 {
902         struct irb *irb;
903
904         irb = (struct irb *) __LC_IRB;
905         /* Accumulate status. We don't do basic sense. */
906         ccw_device_accumulate_irb(cdev, irb);
907         /* Remember to clear irb to avoid residuals. */
908         memset(&cdev->private->irb, 0, sizeof(struct irb));
909         /* Try to start delayed device verification. */
910         ccw_device_online_verify(cdev, 0);
911         /* Note: Don't call handler for cio initiated clear! */
912 }
913
914 static void
915 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
916 {
917         struct subchannel *sch;
918
919         sch = to_subchannel(cdev->dev.parent);
920         ccw_device_set_timeout(cdev, 0);
921         /* Start delayed path verification. */
922         ccw_device_online_verify(cdev, 0);
923         /* OK, i/o is dead now. Call interrupt handler. */
924         if (cdev->handler)
925                 cdev->handler(cdev, cdev->private->intparm,
926                               ERR_PTR(-EIO));
927 }
928
929 static void
930 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
931 {
932         int ret;
933
934         ret = ccw_device_cancel_halt_clear(cdev);
935         if (ret == -EBUSY) {
936                 ccw_device_set_timeout(cdev, 3*HZ);
937                 return;
938         }
939         /* Start delayed path verification. */
940         ccw_device_online_verify(cdev, 0);
941         if (cdev->handler)
942                 cdev->handler(cdev, cdev->private->intparm,
943                               ERR_PTR(-EIO));
944 }
945
946 void ccw_device_kill_io(struct ccw_device *cdev)
947 {
948         int ret;
949
950         ret = ccw_device_cancel_halt_clear(cdev);
951         if (ret == -EBUSY) {
952                 ccw_device_set_timeout(cdev, 3*HZ);
953                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
954                 return;
955         }
956         /* Start delayed path verification. */
957         ccw_device_online_verify(cdev, 0);
958         if (cdev->handler)
959                 cdev->handler(cdev, cdev->private->intparm,
960                               ERR_PTR(-EIO));
961 }
962
963 static void
964 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
965 {
966         /* Start verification after current task finished. */
967         cdev->private->flags.doverify = 1;
968 }
969
970 static void
971 ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event)
972 {
973         struct irb *irb;
974
975         switch (dev_event) {
976         case DEV_EVENT_INTERRUPT:
977                 irb = (struct irb *) __LC_IRB;
978                 /* Check for unsolicited interrupt. */
979                 if ((scsw_stctl(&irb->scsw) ==
980                      (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
981                     (!scsw_cc(&irb->scsw)))
982                         /* FIXME: we should restart stlck here, but this
983                          * is extremely unlikely ... */
984                         goto out_wakeup;
985
986                 ccw_device_accumulate_irb(cdev, irb);
987                 /* We don't care about basic sense etc. */
988                 break;
989         default: /* timeout */
990                 break;
991         }
992 out_wakeup:
993         wake_up(&cdev->private->wait_q);
994 }
995
996 static void
997 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
998 {
999         struct subchannel *sch;
1000
1001         sch = to_subchannel(cdev->dev.parent);
1002         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
1003                 /* Couldn't enable the subchannel for i/o. Sick device. */
1004                 return;
1005
1006         /* After 60s the device recognition is considered to have failed. */
1007         ccw_device_set_timeout(cdev, 60*HZ);
1008
1009         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
1010         ccw_device_sense_id_start(cdev);
1011 }
1012
1013 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
1014 {
1015         struct subchannel *sch;
1016
1017         if (cdev->private->state != DEV_STATE_DISCONNECTED)
1018                 return;
1019
1020         sch = to_subchannel(cdev->dev.parent);
1021         /* Update some values. */
1022         if (cio_update_schib(sch))
1023                 return;
1024         /*
1025          * The pim, pam, pom values may not be accurate, but they are the best
1026          * we have before performing device selection :/
1027          */
1028         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1029         /*
1030          * Use the initial configuration since we can't be shure that the old
1031          * paths are valid.
1032          */
1033         io_subchannel_init_config(sch);
1034         if (cio_commit_config(sch))
1035                 return;
1036
1037         /* We should also udate ssd info, but this has to wait. */
1038         /* Check if this is another device which appeared on the same sch. */
1039         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1040                 PREPARE_WORK(&cdev->private->kick_work,
1041                              ccw_device_move_to_orphanage);
1042                 queue_work(slow_path_wq, &cdev->private->kick_work);
1043         } else
1044                 ccw_device_start_id(cdev, 0);
1045 }
1046
1047 static void
1048 ccw_device_offline_irq(struct ccw_device *cdev, enum dev_event dev_event)
1049 {
1050         struct subchannel *sch;
1051
1052         sch = to_subchannel(cdev->dev.parent);
1053         /*
1054          * An interrupt in state offline means a previous disable was not
1055          * successful. Try again.
1056          */
1057         cio_disable_subchannel(sch);
1058 }
1059
1060 static void
1061 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
1062 {
1063         retry_set_schib(cdev);
1064         cdev->private->state = DEV_STATE_ONLINE;
1065         dev_fsm_event(cdev, dev_event);
1066 }
1067
1068 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
1069                                        enum dev_event dev_event)
1070 {
1071         cmf_retry_copy_block(cdev);
1072         cdev->private->state = DEV_STATE_ONLINE;
1073         dev_fsm_event(cdev, dev_event);
1074 }
1075
1076 static void
1077 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1078 {
1079         ccw_device_set_timeout(cdev, 0);
1080         if (dev_event == DEV_EVENT_NOTOPER)
1081                 cdev->private->state = DEV_STATE_NOT_OPER;
1082         else
1083                 cdev->private->state = DEV_STATE_OFFLINE;
1084         wake_up(&cdev->private->wait_q);
1085 }
1086
1087 static void
1088 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1089 {
1090         int ret;
1091
1092         ret = ccw_device_cancel_halt_clear(cdev);
1093         switch (ret) {
1094         case 0:
1095                 cdev->private->state = DEV_STATE_OFFLINE;
1096                 wake_up(&cdev->private->wait_q);
1097                 break;
1098         case -ENODEV:
1099                 cdev->private->state = DEV_STATE_NOT_OPER;
1100                 wake_up(&cdev->private->wait_q);
1101                 break;
1102         default:
1103                 ccw_device_set_timeout(cdev, HZ/10);
1104         }
1105 }
1106
1107 /*
1108  * No operation action. This is used e.g. to ignore a timeout event in
1109  * state offline.
1110  */
1111 static void
1112 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1113 {
1114 }
1115
1116 /*
1117  * Bug operation action. 
1118  */
1119 static void
1120 ccw_device_bug(struct ccw_device *cdev, enum dev_event dev_event)
1121 {
1122         CIO_MSG_EVENT(0, "Internal state [%i][%i] not handled for device "
1123                       "0.%x.%04x\n", cdev->private->state, dev_event,
1124                       cdev->private->dev_id.ssid,
1125                       cdev->private->dev_id.devno);
1126         BUG();
1127 }
1128
1129 /*
1130  * device statemachine
1131  */
1132 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1133         [DEV_STATE_NOT_OPER] = {
1134                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1135                 [DEV_EVENT_INTERRUPT]   = ccw_device_bug,
1136                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1137                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1138         },
1139         [DEV_STATE_SENSE_PGID] = {
1140                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1141                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_pgid_irq,
1142                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1143                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1144         },
1145         [DEV_STATE_SENSE_ID] = {
1146                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1147                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1148                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1149                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1150         },
1151         [DEV_STATE_OFFLINE] = {
1152                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1153                 [DEV_EVENT_INTERRUPT]   = ccw_device_offline_irq,
1154                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1155                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1156         },
1157         [DEV_STATE_VERIFY] = {
1158                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1159                 [DEV_EVENT_INTERRUPT]   = ccw_device_verify_irq,
1160                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1161                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1162         },
1163         [DEV_STATE_ONLINE] = {
1164                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1165                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1166                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1167                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1168         },
1169         [DEV_STATE_W4SENSE] = {
1170                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1171                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1172                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1173                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1174         },
1175         [DEV_STATE_DISBAND_PGID] = {
1176                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1177                 [DEV_EVENT_INTERRUPT]   = ccw_device_disband_irq,
1178                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1179                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1180         },
1181         [DEV_STATE_BOXED] = {
1182                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1183                 [DEV_EVENT_INTERRUPT]   = ccw_device_stlck_done,
1184                 [DEV_EVENT_TIMEOUT]     = ccw_device_stlck_done,
1185                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1186         },
1187         /* states to wait for i/o completion before doing something */
1188         [DEV_STATE_CLEAR_VERIFY] = {
1189                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1190                 [DEV_EVENT_INTERRUPT]   = ccw_device_clear_verify,
1191                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1192                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1193         },
1194         [DEV_STATE_TIMEOUT_KILL] = {
1195                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1196                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1197                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1198                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1199         },
1200         [DEV_STATE_QUIESCE] = {
1201                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1202                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1203                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1204                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1205         },
1206         /* special states for devices gone not operational */
1207         [DEV_STATE_DISCONNECTED] = {
1208                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1209                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1210                 [DEV_EVENT_TIMEOUT]     = ccw_device_bug,
1211                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1212         },
1213         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1214                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1215                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1216                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1217                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1218         },
1219         [DEV_STATE_CMFCHANGE] = {
1220                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1221                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1222                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1223                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1224         },
1225         [DEV_STATE_CMFUPDATE] = {
1226                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1227                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1228                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1229                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1230         },
1231 };
1232
1233 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);