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