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