Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[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", cdev->dev.bus_id);
56         printk(KERN_WARNING "cio: subchannel bus id: %s\n", sch->dev.bus_id);
57         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
58                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
59
60         if (orb->tm.b) {
61                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
62                 printk(KERN_WARNING "cio: last tcw:\n");
63                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
64                                (void *)(addr_t)orb->tm.tcw,
65                                sizeof(struct tcw), 0);
66         } else {
67                 printk(KERN_WARNING "cio: orb indicates command mode\n");
68                 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
69                     (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
70                         printk(KERN_WARNING "cio: last channel program "
71                                "(intern):\n");
72                 else
73                         printk(KERN_WARNING "cio: last channel program:\n");
74
75                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
76                                (void *)(addr_t)orb->cmd.cpa,
77                                sizeof(struct ccw1), 0);
78         }
79         printk(KERN_WARNING "cio: ccw device state: %d\n",
80                cdev->private->state);
81         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
82         printk(KERN_WARNING "cio: schib:\n");
83         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
84                        &schib, sizeof(schib), 0);
85         printk(KERN_WARNING "cio: ccw device flags:\n");
86         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
87                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
88 }
89
90 /*
91  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
92  */
93 static void
94 ccw_device_timeout(unsigned long data)
95 {
96         struct ccw_device *cdev;
97
98         cdev = (struct ccw_device *) data;
99         spin_lock_irq(cdev->ccwlock);
100         if (timeout_log_enabled)
101                 ccw_timeout_log(cdev);
102         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
103         spin_unlock_irq(cdev->ccwlock);
104 }
105
106 /*
107  * Set timeout
108  */
109 void
110 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
111 {
112         if (expires == 0) {
113                 del_timer(&cdev->private->timer);
114                 return;
115         }
116         if (timer_pending(&cdev->private->timer)) {
117                 if (mod_timer(&cdev->private->timer, jiffies + expires))
118                         return;
119         }
120         cdev->private->timer.function = ccw_device_timeout;
121         cdev->private->timer.data = (unsigned long) cdev;
122         cdev->private->timer.expires = jiffies + expires;
123         add_timer(&cdev->private->timer);
124 }
125
126 /*
127  * Cancel running i/o. This is called repeatedly since halt/clear are
128  * asynchronous operations. We do one try with cio_cancel, two tries
129  * with cio_halt, 255 tries with cio_clear. If everythings fails panic.
130  * Returns 0 if device now idle, -ENODEV for device not operational and
131  * -EBUSY if an interrupt is expected (either from halt/clear or from a
132  * status pending).
133  */
134 int
135 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
136 {
137         struct subchannel *sch;
138         int ret;
139
140         sch = to_subchannel(cdev->dev.parent);
141         ret = stsch(sch->schid, &sch->schib);
142         if (ret || !sch->schib.pmcw.dnv)
143                 return -ENODEV; 
144         if (!sch->schib.pmcw.ena)
145                 /* Not operational -> done. */
146                 return 0;
147         /* Stage 1: cancel io. */
148         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
149             !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
150                 if (!scsw_is_tm(&sch->schib.scsw)) {
151                         ret = cio_cancel(sch);
152                         if (ret != -EINVAL)
153                                 return ret;
154                 }
155                 /* cancel io unsuccessful or not applicable (transport mode).
156                  * Continue with asynchronous instructions. */
157                 cdev->private->iretry = 3;      /* 3 halt retries. */
158         }
159         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
160                 /* Stage 2: halt io. */
161                 if (cdev->private->iretry) {
162                         cdev->private->iretry--;
163                         ret = cio_halt(sch);
164                         if (ret != -EBUSY)
165                                 return (ret == 0) ? -EBUSY : ret;
166                 }
167                 /* halt io unsuccessful. */
168                 cdev->private->iretry = 255;    /* 255 clear retries. */
169         }
170         /* Stage 3: clear io. */
171         if (cdev->private->iretry) {
172                 cdev->private->iretry--;
173                 ret = cio_clear (sch);
174                 return (ret == 0) ? -EBUSY : ret;
175         }
176         panic("Can't stop i/o on subchannel.\n");
177 }
178
179 static int
180 ccw_device_handle_oper(struct ccw_device *cdev)
181 {
182         struct subchannel *sch;
183
184         sch = to_subchannel(cdev->dev.parent);
185         cdev->private->flags.recog_done = 1;
186         /*
187          * Check if cu type and device type still match. If
188          * not, it is certainly another device and we have to
189          * de- and re-register.
190          */
191         if (cdev->id.cu_type != cdev->private->senseid.cu_type ||
192             cdev->id.cu_model != cdev->private->senseid.cu_model ||
193             cdev->id.dev_type != cdev->private->senseid.dev_type ||
194             cdev->id.dev_model != cdev->private->senseid.dev_model) {
195                 PREPARE_WORK(&cdev->private->kick_work,
196                              ccw_device_do_unreg_rereg);
197                 queue_work(ccw_device_work, &cdev->private->kick_work);
198                 return 0;
199         }
200         cdev->private->flags.donotify = 1;
201         return 1;
202 }
203
204 /*
205  * The machine won't give us any notification by machine check if a chpid has
206  * been varied online on the SE so we have to find out by magic (i. e. driving
207  * the channel subsystem to device selection and updating our path masks).
208  */
209 static void
210 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
211 {
212         int mask, i;
213         struct chp_id chpid;
214
215         chp_id_init(&chpid);
216         for (i = 0; i<8; i++) {
217                 mask = 0x80 >> i;
218                 if (!(sch->lpm & mask))
219                         continue;
220                 if (old_lpm & mask)
221                         continue;
222                 chpid.id = sch->schib.pmcw.chpid[i];
223                 if (!chp_is_registered(chpid))
224                         css_schedule_eval_all();
225         }
226 }
227
228 /*
229  * Stop device recognition.
230  */
231 static void
232 ccw_device_recog_done(struct ccw_device *cdev, int state)
233 {
234         struct subchannel *sch;
235         int notify, old_lpm, same_dev;
236
237         sch = to_subchannel(cdev->dev.parent);
238
239         ccw_device_set_timeout(cdev, 0);
240         cio_disable_subchannel(sch);
241         /*
242          * Now that we tried recognition, we have performed device selection
243          * through ssch() and the path information is up to date.
244          */
245         old_lpm = sch->lpm;
246         stsch(sch->schid, &sch->schib);
247         sch->lpm = sch->schib.pmcw.pam & sch->opm;
248         /* Check since device may again have become not operational. */
249         if (!sch->schib.pmcw.dnv)
250                 state = DEV_STATE_NOT_OPER;
251         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
252                 /* Force reprobe on all chpids. */
253                 old_lpm = 0;
254         if (sch->lpm != old_lpm)
255                 __recover_lost_chpids(sch, old_lpm);
256         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
257                 if (state == DEV_STATE_NOT_OPER) {
258                         cdev->private->flags.recog_done = 1;
259                         cdev->private->state = DEV_STATE_DISCONNECTED;
260                         return;
261                 }
262                 /* Boxed devices don't need extra treatment. */
263         }
264         notify = 0;
265         same_dev = 0; /* Keep the compiler quiet... */
266         switch (state) {
267         case DEV_STATE_NOT_OPER:
268                 CIO_MSG_EVENT(2, "SenseID : unknown device %04x on "
269                               "subchannel 0.%x.%04x\n",
270                               cdev->private->dev_id.devno,
271                               sch->schid.ssid, sch->schid.sch_no);
272                 break;
273         case DEV_STATE_OFFLINE:
274                 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
275                         same_dev = ccw_device_handle_oper(cdev);
276                         notify = 1;
277                 }
278                 /* fill out sense information */
279                 memset(&cdev->id, 0, sizeof(cdev->id));
280                 cdev->id.cu_type   = cdev->private->senseid.cu_type;
281                 cdev->id.cu_model  = cdev->private->senseid.cu_model;
282                 cdev->id.dev_type  = cdev->private->senseid.dev_type;
283                 cdev->id.dev_model = cdev->private->senseid.dev_model;
284                 if (notify) {
285                         cdev->private->state = DEV_STATE_OFFLINE;
286                         if (same_dev) {
287                                 /* Get device online again. */
288                                 ccw_device_online(cdev);
289                                 wake_up(&cdev->private->wait_q);
290                         }
291                         return;
292                 }
293                 /* Issue device info message. */
294                 CIO_MSG_EVENT(4, "SenseID : device 0.%x.%04x reports: "
295                               "CU  Type/Mod = %04X/%02X, Dev Type/Mod = "
296                               "%04X/%02X\n",
297                               cdev->private->dev_id.ssid,
298                               cdev->private->dev_id.devno,
299                               cdev->id.cu_type, cdev->id.cu_model,
300                               cdev->id.dev_type, cdev->id.dev_model);
301                 break;
302         case DEV_STATE_BOXED:
303                 CIO_MSG_EVENT(0, "SenseID : boxed device %04x on "
304                               " subchannel 0.%x.%04x\n",
305                               cdev->private->dev_id.devno,
306                               sch->schid.ssid, sch->schid.sch_no);
307                 break;
308         }
309         cdev->private->state = state;
310         io_subchannel_recog_done(cdev);
311         if (state != DEV_STATE_NOT_OPER)
312                 wake_up(&cdev->private->wait_q);
313 }
314
315 /*
316  * Function called from device_id.c after sense id has completed.
317  */
318 void
319 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
320 {
321         switch (err) {
322         case 0:
323                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
324                 break;
325         case -ETIME:            /* Sense id stopped by timeout. */
326                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
327                 break;
328         default:
329                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
330                 break;
331         }
332 }
333
334 int ccw_device_notify(struct ccw_device *cdev, int event)
335 {
336         if (!cdev->drv)
337                 return 0;
338         if (!cdev->online)
339                 return 0;
340         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
341                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
342                       event);
343         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
344 }
345
346 static void cmf_reenable_delayed(struct work_struct *work)
347 {
348         struct ccw_device_private *priv;
349         struct ccw_device *cdev;
350
351         priv = container_of(work, struct ccw_device_private, kick_work);
352         cdev = priv->cdev;
353         cmf_reenable(cdev);
354 }
355
356 static void ccw_device_oper_notify(struct ccw_device *cdev)
357 {
358         if (ccw_device_notify(cdev, CIO_OPER)) {
359                 /* Reenable channel measurements, if needed. */
360                 PREPARE_WORK(&cdev->private->kick_work, cmf_reenable_delayed);
361                 queue_work(ccw_device_work, &cdev->private->kick_work);
362                 return;
363         }
364         /* Driver doesn't want device back. */
365         ccw_device_set_notoper(cdev);
366         PREPARE_WORK(&cdev->private->kick_work, ccw_device_do_unreg_rereg);
367         queue_work(ccw_device_work, &cdev->private->kick_work);
368 }
369
370 /*
371  * Finished with online/offline processing.
372  */
373 static void
374 ccw_device_done(struct ccw_device *cdev, int state)
375 {
376         struct subchannel *sch;
377
378         sch = to_subchannel(cdev->dev.parent);
379
380         ccw_device_set_timeout(cdev, 0);
381
382         if (state != DEV_STATE_ONLINE)
383                 cio_disable_subchannel(sch);
384
385         /* Reset device status. */
386         memset(&cdev->private->irb, 0, sizeof(struct irb));
387
388         cdev->private->state = state;
389
390
391         if (state == DEV_STATE_BOXED)
392                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
393                               cdev->private->dev_id.devno, sch->schid.sch_no);
394
395         if (cdev->private->flags.donotify) {
396                 cdev->private->flags.donotify = 0;
397                 ccw_device_oper_notify(cdev);
398         }
399         wake_up(&cdev->private->wait_q);
400
401         if (css_init_done && state != DEV_STATE_ONLINE)
402                 put_device (&cdev->dev);
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         stsch(sch->schid, &sch->schib);
554         /* Update lpm with verified path mask. */
555         sch->lpm = sch->vpm;
556         /* Repeat path verification? */
557         if (cdev->private->flags.doverify) {
558                 cdev->private->flags.doverify = 0;
559                 ccw_device_verify_start(cdev);
560                 return;
561         }
562         switch (err) {
563         case -EOPNOTSUPP: /* path grouping not supported, just set online. */
564                 cdev->private->options.pgroup = 0;
565         case 0:
566                 ccw_device_done(cdev, DEV_STATE_ONLINE);
567                 /* Deliver fake irb to device driver, if needed. */
568                 if (cdev->private->flags.fake_irb) {
569                         memset(&cdev->private->irb, 0, sizeof(struct irb));
570                         cdev->private->irb.scsw.cmd.cc = 1;
571                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
572                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
573                         cdev->private->irb.scsw.cmd.stctl =
574                                 SCSW_STCTL_STATUS_PEND;
575                         cdev->private->flags.fake_irb = 0;
576                         if (cdev->handler)
577                                 cdev->handler(cdev, cdev->private->intparm,
578                                               &cdev->private->irb);
579                         memset(&cdev->private->irb, 0, sizeof(struct irb));
580                 }
581                 break;
582         case -ETIME:
583                 /* Reset oper notify indication after verify error. */
584                 cdev->private->flags.donotify = 0;
585                 ccw_device_done(cdev, DEV_STATE_BOXED);
586                 break;
587         default:
588                 /* Reset oper notify indication after verify error. */
589                 cdev->private->flags.donotify = 0;
590                 if (cdev->online) {
591                         ccw_device_set_timeout(cdev, 0);
592                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
593                 } else
594                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
595                 break;
596         }
597 }
598
599 /*
600  * Get device online.
601  */
602 int
603 ccw_device_online(struct ccw_device *cdev)
604 {
605         struct subchannel *sch;
606         int ret;
607
608         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
609             (cdev->private->state != DEV_STATE_BOXED))
610                 return -EINVAL;
611         sch = to_subchannel(cdev->dev.parent);
612         if (css_init_done && !get_device(&cdev->dev))
613                 return -ENODEV;
614         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
615         if (ret != 0) {
616                 /* Couldn't enable the subchannel for i/o. Sick device. */
617                 if (ret == -ENODEV)
618                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
619                 return ret;
620         }
621         /* Do we want to do path grouping? */
622         if (!cdev->private->options.pgroup) {
623                 /* Start initial path verification. */
624                 cdev->private->state = DEV_STATE_VERIFY;
625                 cdev->private->flags.doverify = 0;
626                 ccw_device_verify_start(cdev);
627                 return 0;
628         }
629         /* Do a SensePGID first. */
630         cdev->private->state = DEV_STATE_SENSE_PGID;
631         ccw_device_sense_pgid_start(cdev);
632         return 0;
633 }
634
635 void
636 ccw_device_disband_done(struct ccw_device *cdev, int err)
637 {
638         switch (err) {
639         case 0:
640                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
641                 break;
642         case -ETIME:
643                 ccw_device_done(cdev, DEV_STATE_BOXED);
644                 break;
645         default:
646                 cdev->private->flags.donotify = 0;
647                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
648                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
649                 break;
650         }
651 }
652
653 /*
654  * Shutdown device.
655  */
656 int
657 ccw_device_offline(struct ccw_device *cdev)
658 {
659         struct subchannel *sch;
660
661         if (ccw_device_is_orphan(cdev)) {
662                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
663                 return 0;
664         }
665         sch = to_subchannel(cdev->dev.parent);
666         if (stsch(sch->schid, &sch->schib) || !sch->schib.pmcw.dnv)
667                 return -ENODEV;
668         if (scsw_actl(&sch->schib.scsw) != 0)
669                 return -EBUSY;
670         if (cdev->private->state != DEV_STATE_ONLINE)
671                 return -EINVAL;
672         /* Are we doing path grouping? */
673         if (!cdev->private->options.pgroup) {
674                 /* No, set state offline immediately. */
675                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
676                 return 0;
677         }
678         /* Start Set Path Group commands. */
679         cdev->private->state = DEV_STATE_DISBAND_PGID;
680         ccw_device_disband_start(cdev);
681         return 0;
682 }
683
684 /*
685  * Handle timeout in device online/offline process.
686  */
687 static void
688 ccw_device_onoff_timeout(struct ccw_device *cdev, enum dev_event dev_event)
689 {
690         int ret;
691
692         ret = ccw_device_cancel_halt_clear(cdev);
693         switch (ret) {
694         case 0:
695                 ccw_device_done(cdev, DEV_STATE_BOXED);
696                 break;
697         case -ENODEV:
698                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
699                 break;
700         default:
701                 ccw_device_set_timeout(cdev, 3*HZ);
702         }
703 }
704
705 /*
706  * Handle not oper event in device recognition.
707  */
708 static void
709 ccw_device_recog_notoper(struct ccw_device *cdev, enum dev_event dev_event)
710 {
711         ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
712 }
713
714 /*
715  * Handle not operational event in non-special state.
716  */
717 static void ccw_device_generic_notoper(struct ccw_device *cdev,
718                                        enum dev_event dev_event)
719 {
720         struct subchannel *sch;
721
722         cdev->private->state = DEV_STATE_NOT_OPER;
723         sch = to_subchannel(cdev->dev.parent);
724         css_schedule_eval(sch->schid);
725 }
726
727 /*
728  * Handle path verification event.
729  */
730 static void
731 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
732 {
733         struct subchannel *sch;
734
735         if (cdev->private->state == DEV_STATE_W4SENSE) {
736                 cdev->private->flags.doverify = 1;
737                 return;
738         }
739         sch = to_subchannel(cdev->dev.parent);
740         /*
741          * Since we might not just be coming from an interrupt from the
742          * subchannel we have to update the schib.
743          */
744         stsch(sch->schid, &sch->schib);
745
746         if (scsw_actl(&sch->schib.scsw) != 0 ||
747             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
748             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
749                 /*
750                  * No final status yet or final status not yet delivered
751                  * to the device driver. Can't do path verfication now,
752                  * delay until final status was delivered.
753                  */
754                 cdev->private->flags.doverify = 1;
755                 return;
756         }
757         /* Device is idle, we can do the path verification. */
758         cdev->private->state = DEV_STATE_VERIFY;
759         cdev->private->flags.doverify = 0;
760         ccw_device_verify_start(cdev);
761 }
762
763 /*
764  * Got an interrupt for a normal io (state online).
765  */
766 static void
767 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
768 {
769         struct irb *irb;
770         int is_cmd;
771
772         irb = (struct irb *) __LC_IRB;
773         is_cmd = !scsw_is_tm(&irb->scsw);
774         /* Check for unsolicited interrupt. */
775         if (!scsw_is_solicited(&irb->scsw)) {
776                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
777                     !irb->esw.esw0.erw.cons) {
778                         /* Unit check but no sense data. Need basic sense. */
779                         if (ccw_device_do_sense(cdev, irb) != 0)
780                                 goto call_handler_unsol;
781                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
782                         cdev->private->state = DEV_STATE_W4SENSE;
783                         cdev->private->intparm = 0;
784                         return;
785                 }
786 call_handler_unsol:
787                 if (cdev->handler)
788                         cdev->handler (cdev, 0, irb);
789                 if (cdev->private->flags.doverify)
790                         ccw_device_online_verify(cdev, 0);
791                 return;
792         }
793         /* Accumulate status and find out if a basic sense is needed. */
794         ccw_device_accumulate_irb(cdev, irb);
795         if (is_cmd && cdev->private->flags.dosense) {
796                 if (ccw_device_do_sense(cdev, irb) == 0) {
797                         cdev->private->state = DEV_STATE_W4SENSE;
798                 }
799                 return;
800         }
801         /* Call the handler. */
802         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
803                 /* Start delayed path verification. */
804                 ccw_device_online_verify(cdev, 0);
805 }
806
807 /*
808  * Got an timeout in online state.
809  */
810 static void
811 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
812 {
813         int ret;
814
815         ccw_device_set_timeout(cdev, 0);
816         ret = ccw_device_cancel_halt_clear(cdev);
817         if (ret == -EBUSY) {
818                 ccw_device_set_timeout(cdev, 3*HZ);
819                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
820                 return;
821         }
822         if (ret == -ENODEV)
823                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
824         else if (cdev->handler)
825                 cdev->handler(cdev, cdev->private->intparm,
826                               ERR_PTR(-ETIMEDOUT));
827 }
828
829 /*
830  * Got an interrupt for a basic sense.
831  */
832 static void
833 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
834 {
835         struct irb *irb;
836
837         irb = (struct irb *) __LC_IRB;
838         /* Check for unsolicited interrupt. */
839         if (scsw_stctl(&irb->scsw) ==
840             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
841                 if (scsw_cc(&irb->scsw) == 1)
842                         /* Basic sense hasn't started. Try again. */
843                         ccw_device_do_sense(cdev, irb);
844                 else {
845                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
846                                       "interrupt during w4sense...\n",
847                                       cdev->private->dev_id.ssid,
848                                       cdev->private->dev_id.devno);
849                         if (cdev->handler)
850                                 cdev->handler (cdev, 0, irb);
851                 }
852                 return;
853         }
854         /*
855          * Check if a halt or clear has been issued in the meanwhile. If yes,
856          * only deliver the halt/clear interrupt to the device driver as if it
857          * had killed the original request.
858          */
859         if (scsw_fctl(&irb->scsw) &
860             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
861                 /* Retry Basic Sense if requested. */
862                 if (cdev->private->flags.intretry) {
863                         cdev->private->flags.intretry = 0;
864                         ccw_device_do_sense(cdev, irb);
865                         return;
866                 }
867                 cdev->private->flags.dosense = 0;
868                 memset(&cdev->private->irb, 0, sizeof(struct irb));
869                 ccw_device_accumulate_irb(cdev, irb);
870                 goto call_handler;
871         }
872         /* Add basic sense info to irb. */
873         ccw_device_accumulate_basic_sense(cdev, irb);
874         if (cdev->private->flags.dosense) {
875                 /* Another basic sense is needed. */
876                 ccw_device_do_sense(cdev, irb);
877                 return;
878         }
879 call_handler:
880         cdev->private->state = DEV_STATE_ONLINE;
881         /* Call the handler. */
882         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
883                 /* Start delayed path verification. */
884                 ccw_device_online_verify(cdev, 0);
885 }
886
887 static void
888 ccw_device_clear_verify(struct ccw_device *cdev, enum dev_event dev_event)
889 {
890         struct irb *irb;
891
892         irb = (struct irb *) __LC_IRB;
893         /* Accumulate status. We don't do basic sense. */
894         ccw_device_accumulate_irb(cdev, irb);
895         /* Remember to clear irb to avoid residuals. */
896         memset(&cdev->private->irb, 0, sizeof(struct irb));
897         /* Try to start delayed device verification. */
898         ccw_device_online_verify(cdev, 0);
899         /* Note: Don't call handler for cio initiated clear! */
900 }
901
902 static void
903 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
904 {
905         struct subchannel *sch;
906
907         sch = to_subchannel(cdev->dev.parent);
908         ccw_device_set_timeout(cdev, 0);
909         /* Start delayed path verification. */
910         ccw_device_online_verify(cdev, 0);
911         /* OK, i/o is dead now. Call interrupt handler. */
912         if (cdev->handler)
913                 cdev->handler(cdev, cdev->private->intparm,
914                               ERR_PTR(-EIO));
915 }
916
917 static void
918 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
919 {
920         int ret;
921
922         ret = ccw_device_cancel_halt_clear(cdev);
923         if (ret == -EBUSY) {
924                 ccw_device_set_timeout(cdev, 3*HZ);
925                 return;
926         }
927         /* Start delayed path verification. */
928         ccw_device_online_verify(cdev, 0);
929         if (cdev->handler)
930                 cdev->handler(cdev, cdev->private->intparm,
931                               ERR_PTR(-EIO));
932 }
933
934 void ccw_device_kill_io(struct ccw_device *cdev)
935 {
936         int ret;
937
938         ret = ccw_device_cancel_halt_clear(cdev);
939         if (ret == -EBUSY) {
940                 ccw_device_set_timeout(cdev, 3*HZ);
941                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
942                 return;
943         }
944         /* Start delayed path verification. */
945         ccw_device_online_verify(cdev, 0);
946         if (cdev->handler)
947                 cdev->handler(cdev, cdev->private->intparm,
948                               ERR_PTR(-EIO));
949 }
950
951 static void
952 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
953 {
954         /* Start verification after current task finished. */
955         cdev->private->flags.doverify = 1;
956 }
957
958 static void
959 ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event)
960 {
961         struct irb *irb;
962
963         switch (dev_event) {
964         case DEV_EVENT_INTERRUPT:
965                 irb = (struct irb *) __LC_IRB;
966                 /* Check for unsolicited interrupt. */
967                 if ((scsw_stctl(&irb->scsw) ==
968                      (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
969                     (!scsw_cc(&irb->scsw)))
970                         /* FIXME: we should restart stlck here, but this
971                          * is extremely unlikely ... */
972                         goto out_wakeup;
973
974                 ccw_device_accumulate_irb(cdev, irb);
975                 /* We don't care about basic sense etc. */
976                 break;
977         default: /* timeout */
978                 break;
979         }
980 out_wakeup:
981         wake_up(&cdev->private->wait_q);
982 }
983
984 static void
985 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
986 {
987         struct subchannel *sch;
988
989         sch = to_subchannel(cdev->dev.parent);
990         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
991                 /* Couldn't enable the subchannel for i/o. Sick device. */
992                 return;
993
994         /* After 60s the device recognition is considered to have failed. */
995         ccw_device_set_timeout(cdev, 60*HZ);
996
997         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
998         ccw_device_sense_id_start(cdev);
999 }
1000
1001 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
1002 {
1003         struct subchannel *sch;
1004
1005         if (cdev->private->state != DEV_STATE_DISCONNECTED)
1006                 return;
1007
1008         sch = to_subchannel(cdev->dev.parent);
1009         /* Update some values. */
1010         if (stsch(sch->schid, &sch->schib))
1011                 return;
1012         if (!sch->schib.pmcw.dnv)
1013                 return;
1014         /*
1015          * The pim, pam, pom values may not be accurate, but they are the best
1016          * we have before performing device selection :/
1017          */
1018         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1019         /* Re-set some bits in the pmcw that were lost. */
1020         sch->schib.pmcw.csense = 1;
1021         sch->schib.pmcw.ena = 0;
1022         if ((sch->lpm & (sch->lpm - 1)) != 0)
1023                 sch->schib.pmcw.mp = 1;
1024         /* We should also udate ssd info, but this has to wait. */
1025         /* Check if this is another device which appeared on the same sch. */
1026         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1027                 PREPARE_WORK(&cdev->private->kick_work,
1028                              ccw_device_move_to_orphanage);
1029                 queue_work(slow_path_wq, &cdev->private->kick_work);
1030         } else
1031                 ccw_device_start_id(cdev, 0);
1032 }
1033
1034 static void
1035 ccw_device_offline_irq(struct ccw_device *cdev, enum dev_event dev_event)
1036 {
1037         struct subchannel *sch;
1038
1039         sch = to_subchannel(cdev->dev.parent);
1040         /*
1041          * An interrupt in state offline means a previous disable was not
1042          * successful. Try again.
1043          */
1044         cio_disable_subchannel(sch);
1045 }
1046
1047 static void
1048 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
1049 {
1050         retry_set_schib(cdev);
1051         cdev->private->state = DEV_STATE_ONLINE;
1052         dev_fsm_event(cdev, dev_event);
1053 }
1054
1055 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
1056                                        enum dev_event dev_event)
1057 {
1058         cmf_retry_copy_block(cdev);
1059         cdev->private->state = DEV_STATE_ONLINE;
1060         dev_fsm_event(cdev, dev_event);
1061 }
1062
1063 static void
1064 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1065 {
1066         ccw_device_set_timeout(cdev, 0);
1067         if (dev_event == DEV_EVENT_NOTOPER)
1068                 cdev->private->state = DEV_STATE_NOT_OPER;
1069         else
1070                 cdev->private->state = DEV_STATE_OFFLINE;
1071         wake_up(&cdev->private->wait_q);
1072 }
1073
1074 static void
1075 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1076 {
1077         int ret;
1078
1079         ret = ccw_device_cancel_halt_clear(cdev);
1080         switch (ret) {
1081         case 0:
1082                 cdev->private->state = DEV_STATE_OFFLINE;
1083                 wake_up(&cdev->private->wait_q);
1084                 break;
1085         case -ENODEV:
1086                 cdev->private->state = DEV_STATE_NOT_OPER;
1087                 wake_up(&cdev->private->wait_q);
1088                 break;
1089         default:
1090                 ccw_device_set_timeout(cdev, HZ/10);
1091         }
1092 }
1093
1094 /*
1095  * No operation action. This is used e.g. to ignore a timeout event in
1096  * state offline.
1097  */
1098 static void
1099 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1100 {
1101 }
1102
1103 /*
1104  * Bug operation action. 
1105  */
1106 static void
1107 ccw_device_bug(struct ccw_device *cdev, enum dev_event dev_event)
1108 {
1109         CIO_MSG_EVENT(0, "Internal state [%i][%i] not handled for device "
1110                       "0.%x.%04x\n", cdev->private->state, dev_event,
1111                       cdev->private->dev_id.ssid,
1112                       cdev->private->dev_id.devno);
1113         BUG();
1114 }
1115
1116 /*
1117  * device statemachine
1118  */
1119 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1120         [DEV_STATE_NOT_OPER] = {
1121                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1122                 [DEV_EVENT_INTERRUPT]   = ccw_device_bug,
1123                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1124                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1125         },
1126         [DEV_STATE_SENSE_PGID] = {
1127                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1128                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_pgid_irq,
1129                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1130                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1131         },
1132         [DEV_STATE_SENSE_ID] = {
1133                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1134                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1135                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1136                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1137         },
1138         [DEV_STATE_OFFLINE] = {
1139                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1140                 [DEV_EVENT_INTERRUPT]   = ccw_device_offline_irq,
1141                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1142                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1143         },
1144         [DEV_STATE_VERIFY] = {
1145                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1146                 [DEV_EVENT_INTERRUPT]   = ccw_device_verify_irq,
1147                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1148                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1149         },
1150         [DEV_STATE_ONLINE] = {
1151                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1152                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1153                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1154                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1155         },
1156         [DEV_STATE_W4SENSE] = {
1157                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1158                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1159                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1160                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1161         },
1162         [DEV_STATE_DISBAND_PGID] = {
1163                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1164                 [DEV_EVENT_INTERRUPT]   = ccw_device_disband_irq,
1165                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1166                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1167         },
1168         [DEV_STATE_BOXED] = {
1169                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1170                 [DEV_EVENT_INTERRUPT]   = ccw_device_stlck_done,
1171                 [DEV_EVENT_TIMEOUT]     = ccw_device_stlck_done,
1172                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1173         },
1174         /* states to wait for i/o completion before doing something */
1175         [DEV_STATE_CLEAR_VERIFY] = {
1176                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1177                 [DEV_EVENT_INTERRUPT]   = ccw_device_clear_verify,
1178                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1179                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1180         },
1181         [DEV_STATE_TIMEOUT_KILL] = {
1182                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1183                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1184                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1185                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1186         },
1187         [DEV_STATE_QUIESCE] = {
1188                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1189                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1190                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1191                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1192         },
1193         /* special states for devices gone not operational */
1194         [DEV_STATE_DISCONNECTED] = {
1195                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1196                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1197                 [DEV_EVENT_TIMEOUT]     = ccw_device_bug,
1198                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1199         },
1200         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1201                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1202                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1203                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1204                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1205         },
1206         [DEV_STATE_CMFCHANGE] = {
1207                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1208                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1209                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1210                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1211         },
1212         [DEV_STATE_CMFUPDATE] = {
1213                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1214                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1215                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1216                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1217         },
1218 };
1219
1220 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);