1 /*
2 * finite state machine for device handling
3 *
4 * Copyright IBM Corp. 2002, 2008
5 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
6 * Martin Schwidefsky (schwidefsky@de.ibm.com)
7 */
8
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/jiffies.h>
12 #include <linux/string.h>
13
14 #include <asm/ccwdev.h>
15 #include <asm/cio.h>
16 #include <asm/chpid.h>
17
18 #include "cio.h"
19 #include "cio_debug.h"
20 #include "css.h"
21 #include "device.h"
22 #include "chsc.h"
23 #include "ioasm.h"
24 #include "chp.h"
25
26 static int timeout_log_enabled;
27
ccw_timeout_log_setup(char * unused)28 static int __init ccw_timeout_log_setup(char *unused)
29 {
30 timeout_log_enabled = 1;
31 return 1;
32 }
33
34 __setup("ccw_timeout_log", ccw_timeout_log_setup);
35
ccw_timeout_log(struct ccw_device * cdev)36 static void ccw_timeout_log(struct ccw_device *cdev)
37 {
38 struct schib schib;
39 struct subchannel *sch;
40 struct io_subchannel_private *private;
41 union orb *orb;
42 int cc;
43
44 sch = to_subchannel(cdev->dev.parent);
45 private = to_io_private(sch);
46 orb = &private->orb;
47 cc = stsch(sch->schid, &schib);
48
49 printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
50 "device information:\n", get_tod_clock());
51 printk(KERN_WARNING "cio: orb:\n");
52 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
53 orb, sizeof(*orb), 0);
54 printk(KERN_WARNING "cio: ccw device bus id: %s\n",
55 dev_name(&cdev->dev));
56 printk(KERN_WARNING "cio: subchannel bus id: %s\n",
57 dev_name(&sch->dev));
58 printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
59 "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
60
61 if (orb->tm.b) {
62 printk(KERN_WARNING "cio: orb indicates transport mode\n");
63 printk(KERN_WARNING "cio: last tcw:\n");
64 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
65 (void *)(addr_t)orb->tm.tcw,
66 sizeof(struct tcw), 0);
67 } else {
68 printk(KERN_WARNING "cio: orb indicates command mode\n");
69 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
70 (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
71 printk(KERN_WARNING "cio: last channel program "
72 "(intern):\n");
73 else
74 printk(KERN_WARNING "cio: last channel program:\n");
75
76 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
77 (void *)(addr_t)orb->cmd.cpa,
78 sizeof(struct ccw1), 0);
79 }
80 printk(KERN_WARNING "cio: ccw device state: %d\n",
81 cdev->private->state);
82 printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
83 printk(KERN_WARNING "cio: schib:\n");
84 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
85 &schib, sizeof(schib), 0);
86 printk(KERN_WARNING "cio: ccw device flags:\n");
87 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
88 &cdev->private->flags, sizeof(cdev->private->flags), 0);
89 }
90
91 /*
92 * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
93 */
94 static void
ccw_device_timeout(unsigned long data)95 ccw_device_timeout(unsigned long data)
96 {
97 struct ccw_device *cdev;
98
99 cdev = (struct ccw_device *) data;
100 spin_lock_irq(cdev->ccwlock);
101 if (timeout_log_enabled)
102 ccw_timeout_log(cdev);
103 dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
104 spin_unlock_irq(cdev->ccwlock);
105 }
106
107 /*
108 * Set timeout
109 */
110 void
ccw_device_set_timeout(struct ccw_device * cdev,int expires)111 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
112 {
113 if (expires == 0) {
114 del_timer(&cdev->private->timer);
115 return;
116 }
117 if (timer_pending(&cdev->private->timer)) {
118 if (mod_timer(&cdev->private->timer, jiffies + expires))
119 return;
120 }
121 cdev->private->timer.function = ccw_device_timeout;
122 cdev->private->timer.data = (unsigned long) cdev;
123 cdev->private->timer.expires = jiffies + expires;
124 add_timer(&cdev->private->timer);
125 }
126
127 int
ccw_device_cancel_halt_clear(struct ccw_device * cdev)128 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
129 {
130 struct subchannel *sch;
131 int ret;
132
133 sch = to_subchannel(cdev->dev.parent);
134 ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
135
136 if (ret == -EIO)
137 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
138 cdev->private->dev_id.ssid,
139 cdev->private->dev_id.devno);
140
141 return ret;
142 }
143
ccw_device_update_sense_data(struct ccw_device * cdev)144 void ccw_device_update_sense_data(struct ccw_device *cdev)
145 {
146 memset(&cdev->id, 0, sizeof(cdev->id));
147 cdev->id.cu_type = cdev->private->senseid.cu_type;
148 cdev->id.cu_model = cdev->private->senseid.cu_model;
149 cdev->id.dev_type = cdev->private->senseid.dev_type;
150 cdev->id.dev_model = cdev->private->senseid.dev_model;
151 }
152
ccw_device_test_sense_data(struct ccw_device * cdev)153 int ccw_device_test_sense_data(struct ccw_device *cdev)
154 {
155 return cdev->id.cu_type == cdev->private->senseid.cu_type &&
156 cdev->id.cu_model == cdev->private->senseid.cu_model &&
157 cdev->id.dev_type == cdev->private->senseid.dev_type &&
158 cdev->id.dev_model == cdev->private->senseid.dev_model;
159 }
160
161 /*
162 * The machine won't give us any notification by machine check if a chpid has
163 * been varied online on the SE so we have to find out by magic (i. e. driving
164 * the channel subsystem to device selection and updating our path masks).
165 */
166 static void
__recover_lost_chpids(struct subchannel * sch,int old_lpm)167 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
168 {
169 int mask, i;
170 struct chp_id chpid;
171
172 chp_id_init(&chpid);
173 for (i = 0; i<8; i++) {
174 mask = 0x80 >> i;
175 if (!(sch->lpm & mask))
176 continue;
177 if (old_lpm & mask)
178 continue;
179 chpid.id = sch->schib.pmcw.chpid[i];
180 if (!chp_is_registered(chpid))
181 css_schedule_eval_all();
182 }
183 }
184
185 /*
186 * Stop device recognition.
187 */
188 static void
ccw_device_recog_done(struct ccw_device * cdev,int state)189 ccw_device_recog_done(struct ccw_device *cdev, int state)
190 {
191 struct subchannel *sch;
192 int old_lpm;
193
194 sch = to_subchannel(cdev->dev.parent);
195
196 if (cio_disable_subchannel(sch))
197 state = DEV_STATE_NOT_OPER;
198 /*
199 * Now that we tried recognition, we have performed device selection
200 * through ssch() and the path information is up to date.
201 */
202 old_lpm = sch->lpm;
203
204 /* Check since device may again have become not operational. */
205 if (cio_update_schib(sch))
206 state = DEV_STATE_NOT_OPER;
207 else
208 sch->lpm = sch->schib.pmcw.pam & sch->opm;
209
210 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
211 /* Force reprobe on all chpids. */
212 old_lpm = 0;
213 if (sch->lpm != old_lpm)
214 __recover_lost_chpids(sch, old_lpm);
215 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
216 (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
217 cdev->private->flags.recog_done = 1;
218 cdev->private->state = DEV_STATE_DISCONNECTED;
219 wake_up(&cdev->private->wait_q);
220 return;
221 }
222 if (cdev->private->flags.resuming) {
223 cdev->private->state = state;
224 cdev->private->flags.recog_done = 1;
225 wake_up(&cdev->private->wait_q);
226 return;
227 }
228 switch (state) {
229 case DEV_STATE_NOT_OPER:
230 break;
231 case DEV_STATE_OFFLINE:
232 if (!cdev->online) {
233 ccw_device_update_sense_data(cdev);
234 break;
235 }
236 cdev->private->state = DEV_STATE_OFFLINE;
237 cdev->private->flags.recog_done = 1;
238 if (ccw_device_test_sense_data(cdev)) {
239 cdev->private->flags.donotify = 1;
240 ccw_device_online(cdev);
241 wake_up(&cdev->private->wait_q);
242 } else {
243 ccw_device_update_sense_data(cdev);
244 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
245 }
246 return;
247 case DEV_STATE_BOXED:
248 if (cdev->id.cu_type != 0) { /* device was recognized before */
249 cdev->private->flags.recog_done = 1;
250 cdev->private->state = DEV_STATE_BOXED;
251 wake_up(&cdev->private->wait_q);
252 return;
253 }
254 break;
255 }
256 cdev->private->state = state;
257 io_subchannel_recog_done(cdev);
258 wake_up(&cdev->private->wait_q);
259 }
260
261 /*
262 * Function called from device_id.c after sense id has completed.
263 */
264 void
ccw_device_sense_id_done(struct ccw_device * cdev,int err)265 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
266 {
267 switch (err) {
268 case 0:
269 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
270 break;
271 case -ETIME: /* Sense id stopped by timeout. */
272 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
273 break;
274 default:
275 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
276 break;
277 }
278 }
279
280 /**
281 * ccw_device_notify() - inform the device's driver about an event
282 * @cdev: device for which an event occurred
283 * @event: event that occurred
284 *
285 * Returns:
286 * -%EINVAL if the device is offline or has no driver.
287 * -%EOPNOTSUPP if the device's driver has no notifier registered.
288 * %NOTIFY_OK if the driver wants to keep the device.
289 * %NOTIFY_BAD if the driver doesn't want to keep the device.
290 */
ccw_device_notify(struct ccw_device * cdev,int event)291 int ccw_device_notify(struct ccw_device *cdev, int event)
292 {
293 int ret = -EINVAL;
294
295 if (!cdev->drv)
296 goto out;
297 if (!cdev->online)
298 goto out;
299 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
300 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
301 event);
302 if (!cdev->drv->notify) {
303 ret = -EOPNOTSUPP;
304 goto out;
305 }
306 if (cdev->drv->notify(cdev, event))
307 ret = NOTIFY_OK;
308 else
309 ret = NOTIFY_BAD;
310 out:
311 return ret;
312 }
313
ccw_device_oper_notify(struct ccw_device * cdev)314 static void ccw_device_oper_notify(struct ccw_device *cdev)
315 {
316 struct subchannel *sch = to_subchannel(cdev->dev.parent);
317
318 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
319 /* Reenable channel measurements, if needed. */
320 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
321 /* Save indication for new paths. */
322 cdev->private->path_new_mask = sch->vpm;
323 return;
324 }
325 /* Driver doesn't want device back. */
326 ccw_device_set_notoper(cdev);
327 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
328 }
329
330 /*
331 * Finished with online/offline processing.
332 */
333 static void
ccw_device_done(struct ccw_device * cdev,int state)334 ccw_device_done(struct ccw_device *cdev, int state)
335 {
336 struct subchannel *sch;
337
338 sch = to_subchannel(cdev->dev.parent);
339
340 ccw_device_set_timeout(cdev, 0);
341
342 if (state != DEV_STATE_ONLINE)
343 cio_disable_subchannel(sch);
344
345 /* Reset device status. */
346 memset(&cdev->private->irb, 0, sizeof(struct irb));
347
348 cdev->private->state = state;
349
350 switch (state) {
351 case DEV_STATE_BOXED:
352 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
353 cdev->private->dev_id.devno, sch->schid.sch_no);
354 if (cdev->online &&
355 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
356 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
357 cdev->private->flags.donotify = 0;
358 break;
359 case DEV_STATE_NOT_OPER:
360 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
361 cdev->private->dev_id.devno, sch->schid.sch_no);
362 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
363 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
364 else
365 ccw_device_set_disconnected(cdev);
366 cdev->private->flags.donotify = 0;
367 break;
368 case DEV_STATE_DISCONNECTED:
369 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
370 "%04x\n", cdev->private->dev_id.devno,
371 sch->schid.sch_no);
372 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
373 cdev->private->state = DEV_STATE_NOT_OPER;
374 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
375 } else
376 ccw_device_set_disconnected(cdev);
377 cdev->private->flags.donotify = 0;
378 break;
379 default:
380 break;
381 }
382
383 if (cdev->private->flags.donotify) {
384 cdev->private->flags.donotify = 0;
385 ccw_device_oper_notify(cdev);
386 }
387 wake_up(&cdev->private->wait_q);
388 }
389
390 /*
391 * Start device recognition.
392 */
ccw_device_recognition(struct ccw_device * cdev)393 void ccw_device_recognition(struct ccw_device *cdev)
394 {
395 struct subchannel *sch = to_subchannel(cdev->dev.parent);
396
397 /*
398 * We used to start here with a sense pgid to find out whether a device
399 * is locked by someone else. Unfortunately, the sense pgid command
400 * code has other meanings on devices predating the path grouping
401 * algorithm, so we start with sense id and box the device after an
402 * timeout (or if sense pgid during path verification detects the device
403 * is locked, as may happen on newer devices).
404 */
405 cdev->private->flags.recog_done = 0;
406 cdev->private->state = DEV_STATE_SENSE_ID;
407 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
408 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
409 return;
410 }
411 ccw_device_sense_id_start(cdev);
412 }
413
414 /*
415 * Handle events for states that use the ccw request infrastructure.
416 */
ccw_device_request_event(struct ccw_device * cdev,enum dev_event e)417 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
418 {
419 switch (e) {
420 case DEV_EVENT_NOTOPER:
421 ccw_request_notoper(cdev);
422 break;
423 case DEV_EVENT_INTERRUPT:
424 ccw_request_handler(cdev);
425 break;
426 case DEV_EVENT_TIMEOUT:
427 ccw_request_timeout(cdev);
428 break;
429 default:
430 break;
431 }
432 }
433
ccw_device_report_path_events(struct ccw_device * cdev)434 static void ccw_device_report_path_events(struct ccw_device *cdev)
435 {
436 struct subchannel *sch = to_subchannel(cdev->dev.parent);
437 int path_event[8];
438 int chp, mask;
439
440 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
441 path_event[chp] = PE_NONE;
442 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
443 path_event[chp] |= PE_PATH_GONE;
444 if (mask & cdev->private->path_new_mask & sch->vpm)
445 path_event[chp] |= PE_PATH_AVAILABLE;
446 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
447 path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
448 }
449 if (cdev->online && cdev->drv->path_event)
450 cdev->drv->path_event(cdev, path_event);
451 }
452
ccw_device_reset_path_events(struct ccw_device * cdev)453 static void ccw_device_reset_path_events(struct ccw_device *cdev)
454 {
455 cdev->private->path_gone_mask = 0;
456 cdev->private->path_new_mask = 0;
457 cdev->private->pgid_reset_mask = 0;
458 }
459
create_fake_irb(struct irb * irb,int type)460 static void create_fake_irb(struct irb *irb, int type)
461 {
462 memset(irb, 0, sizeof(*irb));
463 if (type == FAKE_CMD_IRB) {
464 struct cmd_scsw *scsw = &irb->scsw.cmd;
465 scsw->cc = 1;
466 scsw->fctl = SCSW_FCTL_START_FUNC;
467 scsw->actl = SCSW_ACTL_START_PEND;
468 scsw->stctl = SCSW_STCTL_STATUS_PEND;
469 } else if (type == FAKE_TM_IRB) {
470 struct tm_scsw *scsw = &irb->scsw.tm;
471 scsw->x = 1;
472 scsw->cc = 1;
473 scsw->fctl = SCSW_FCTL_START_FUNC;
474 scsw->actl = SCSW_ACTL_START_PEND;
475 scsw->stctl = SCSW_STCTL_STATUS_PEND;
476 }
477 }
478
ccw_device_handle_broken_paths(struct ccw_device * cdev)479 static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
480 {
481 struct subchannel *sch = to_subchannel(cdev->dev.parent);
482 u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
483
484 if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
485 ccw_device_schedule_recovery();
486
487 cdev->private->path_broken_mask = broken_paths;
488 }
489
ccw_device_verify_done(struct ccw_device * cdev,int err)490 void ccw_device_verify_done(struct ccw_device *cdev, int err)
491 {
492 struct subchannel *sch;
493
494 sch = to_subchannel(cdev->dev.parent);
495 /* Update schib - pom may have changed. */
496 if (cio_update_schib(sch)) {
497 err = -ENODEV;
498 goto callback;
499 }
500 /* Update lpm with verified path mask. */
501 sch->lpm = sch->vpm;
502 /* Repeat path verification? */
503 if (cdev->private->flags.doverify) {
504 ccw_device_verify_start(cdev);
505 return;
506 }
507 callback:
508 switch (err) {
509 case 0:
510 ccw_device_done(cdev, DEV_STATE_ONLINE);
511 /* Deliver fake irb to device driver, if needed. */
512 if (cdev->private->flags.fake_irb) {
513 create_fake_irb(&cdev->private->irb,
514 cdev->private->flags.fake_irb);
515 cdev->private->flags.fake_irb = 0;
516 if (cdev->handler)
517 cdev->handler(cdev, cdev->private->intparm,
518 &cdev->private->irb);
519 memset(&cdev->private->irb, 0, sizeof(struct irb));
520 }
521 ccw_device_report_path_events(cdev);
522 ccw_device_handle_broken_paths(cdev);
523 break;
524 case -ETIME:
525 case -EUSERS:
526 /* Reset oper notify indication after verify error. */
527 cdev->private->flags.donotify = 0;
528 ccw_device_done(cdev, DEV_STATE_BOXED);
529 break;
530 case -EACCES:
531 /* Reset oper notify indication after verify error. */
532 cdev->private->flags.donotify = 0;
533 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
534 break;
535 default:
536 /* Reset oper notify indication after verify error. */
537 cdev->private->flags.donotify = 0;
538 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
539 break;
540 }
541 ccw_device_reset_path_events(cdev);
542 }
543
544 /*
545 * Get device online.
546 */
547 int
ccw_device_online(struct ccw_device * cdev)548 ccw_device_online(struct ccw_device *cdev)
549 {
550 struct subchannel *sch;
551 int ret;
552
553 if ((cdev->private->state != DEV_STATE_OFFLINE) &&
554 (cdev->private->state != DEV_STATE_BOXED))
555 return -EINVAL;
556 sch = to_subchannel(cdev->dev.parent);
557 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
558 if (ret != 0) {
559 /* Couldn't enable the subchannel for i/o. Sick device. */
560 if (ret == -ENODEV)
561 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
562 return ret;
563 }
564 /* Start initial path verification. */
565 cdev->private->state = DEV_STATE_VERIFY;
566 ccw_device_verify_start(cdev);
567 return 0;
568 }
569
570 void
ccw_device_disband_done(struct ccw_device * cdev,int err)571 ccw_device_disband_done(struct ccw_device *cdev, int err)
572 {
573 switch (err) {
574 case 0:
575 ccw_device_done(cdev, DEV_STATE_OFFLINE);
576 break;
577 case -ETIME:
578 ccw_device_done(cdev, DEV_STATE_BOXED);
579 break;
580 default:
581 cdev->private->flags.donotify = 0;
582 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
583 break;
584 }
585 }
586
587 /*
588 * Shutdown device.
589 */
590 int
ccw_device_offline(struct ccw_device * cdev)591 ccw_device_offline(struct ccw_device *cdev)
592 {
593 struct subchannel *sch;
594
595 /* Allow ccw_device_offline while disconnected. */
596 if (cdev->private->state == DEV_STATE_DISCONNECTED ||
597 cdev->private->state == DEV_STATE_NOT_OPER) {
598 cdev->private->flags.donotify = 0;
599 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
600 return 0;
601 }
602 if (cdev->private->state == DEV_STATE_BOXED) {
603 ccw_device_done(cdev, DEV_STATE_BOXED);
604 return 0;
605 }
606 if (ccw_device_is_orphan(cdev)) {
607 ccw_device_done(cdev, DEV_STATE_OFFLINE);
608 return 0;
609 }
610 sch = to_subchannel(cdev->dev.parent);
611 if (cio_update_schib(sch))
612 return -ENODEV;
613 if (scsw_actl(&sch->schib.scsw) != 0)
614 return -EBUSY;
615 if (cdev->private->state != DEV_STATE_ONLINE)
616 return -EINVAL;
617 /* Are we doing path grouping? */
618 if (!cdev->private->flags.pgroup) {
619 /* No, set state offline immediately. */
620 ccw_device_done(cdev, DEV_STATE_OFFLINE);
621 return 0;
622 }
623 /* Start Set Path Group commands. */
624 cdev->private->state = DEV_STATE_DISBAND_PGID;
625 ccw_device_disband_start(cdev);
626 return 0;
627 }
628
629 /*
630 * Handle not operational event in non-special state.
631 */
ccw_device_generic_notoper(struct ccw_device * cdev,enum dev_event dev_event)632 static void ccw_device_generic_notoper(struct ccw_device *cdev,
633 enum dev_event dev_event)
634 {
635 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
636 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
637 else
638 ccw_device_set_disconnected(cdev);
639 }
640
641 /*
642 * Handle path verification event in offline state.
643 */
ccw_device_offline_verify(struct ccw_device * cdev,enum dev_event dev_event)644 static void ccw_device_offline_verify(struct ccw_device *cdev,
645 enum dev_event dev_event)
646 {
647 struct subchannel *sch = to_subchannel(cdev->dev.parent);
648
649 css_schedule_eval(sch->schid);
650 }
651
652 /*
653 * Handle path verification event.
654 */
655 static void
ccw_device_online_verify(struct ccw_device * cdev,enum dev_event dev_event)656 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
657 {
658 struct subchannel *sch;
659
660 if (cdev->private->state == DEV_STATE_W4SENSE) {
661 cdev->private->flags.doverify = 1;
662 return;
663 }
664 sch = to_subchannel(cdev->dev.parent);
665 /*
666 * Since we might not just be coming from an interrupt from the
667 * subchannel we have to update the schib.
668 */
669 if (cio_update_schib(sch)) {
670 ccw_device_verify_done(cdev, -ENODEV);
671 return;
672 }
673
674 if (scsw_actl(&sch->schib.scsw) != 0 ||
675 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
676 (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
677 /*
678 * No final status yet or final status not yet delivered
679 * to the device driver. Can't do path verification now,
680 * delay until final status was delivered.
681 */
682 cdev->private->flags.doverify = 1;
683 return;
684 }
685 /* Device is idle, we can do the path verification. */
686 cdev->private->state = DEV_STATE_VERIFY;
687 ccw_device_verify_start(cdev);
688 }
689
690 /*
691 * Handle path verification event in boxed state.
692 */
ccw_device_boxed_verify(struct ccw_device * cdev,enum dev_event dev_event)693 static void ccw_device_boxed_verify(struct ccw_device *cdev,
694 enum dev_event dev_event)
695 {
696 struct subchannel *sch = to_subchannel(cdev->dev.parent);
697
698 if (cdev->online) {
699 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
700 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
701 else
702 ccw_device_online_verify(cdev, dev_event);
703 } else
704 css_schedule_eval(sch->schid);
705 }
706
707 /*
708 * Pass interrupt to device driver.
709 */
ccw_device_call_handler(struct ccw_device * cdev)710 static int ccw_device_call_handler(struct ccw_device *cdev)
711 {
712 unsigned int stctl;
713 int ending_status;
714
715 /*
716 * we allow for the device action handler if .
717 * - we received ending status
718 * - the action handler requested to see all interrupts
719 * - we received an intermediate status
720 * - fast notification was requested (primary status)
721 * - unsolicited interrupts
722 */
723 stctl = scsw_stctl(&cdev->private->irb.scsw);
724 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
725 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
726 (stctl == SCSW_STCTL_STATUS_PEND);
727 if (!ending_status &&
728 !cdev->private->options.repall &&
729 !(stctl & SCSW_STCTL_INTER_STATUS) &&
730 !(cdev->private->options.fast &&
731 (stctl & SCSW_STCTL_PRIM_STATUS)))
732 return 0;
733
734 if (ending_status)
735 ccw_device_set_timeout(cdev, 0);
736
737 if (cdev->handler)
738 cdev->handler(cdev, cdev->private->intparm,
739 &cdev->private->irb);
740
741 memset(&cdev->private->irb, 0, sizeof(struct irb));
742 return 1;
743 }
744
745 /*
746 * Got an interrupt for a normal io (state online).
747 */
748 static void
ccw_device_irq(struct ccw_device * cdev,enum dev_event dev_event)749 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
750 {
751 struct irb *irb;
752 int is_cmd;
753
754 irb = this_cpu_ptr(&cio_irb);
755 is_cmd = !scsw_is_tm(&irb->scsw);
756 /* Check for unsolicited interrupt. */
757 if (!scsw_is_solicited(&irb->scsw)) {
758 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
759 !irb->esw.esw0.erw.cons) {
760 /* Unit check but no sense data. Need basic sense. */
761 if (ccw_device_do_sense(cdev, irb) != 0)
762 goto call_handler_unsol;
763 memcpy(&cdev->private->irb, irb, sizeof(struct irb));
764 cdev->private->state = DEV_STATE_W4SENSE;
765 cdev->private->intparm = 0;
766 return;
767 }
768 call_handler_unsol:
769 if (cdev->handler)
770 cdev->handler (cdev, 0, irb);
771 if (cdev->private->flags.doverify)
772 ccw_device_online_verify(cdev, 0);
773 return;
774 }
775 /* Accumulate status and find out if a basic sense is needed. */
776 ccw_device_accumulate_irb(cdev, irb);
777 if (is_cmd && cdev->private->flags.dosense) {
778 if (ccw_device_do_sense(cdev, irb) == 0) {
779 cdev->private->state = DEV_STATE_W4SENSE;
780 }
781 return;
782 }
783 /* Call the handler. */
784 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
785 /* Start delayed path verification. */
786 ccw_device_online_verify(cdev, 0);
787 }
788
789 /*
790 * Got an timeout in online state.
791 */
792 static void
ccw_device_online_timeout(struct ccw_device * cdev,enum dev_event dev_event)793 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
794 {
795 int ret;
796
797 ccw_device_set_timeout(cdev, 0);
798 cdev->private->iretry = 255;
799 cdev->private->async_kill_io_rc = -ETIMEDOUT;
800 ret = ccw_device_cancel_halt_clear(cdev);
801 if (ret == -EBUSY) {
802 ccw_device_set_timeout(cdev, 3*HZ);
803 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
804 return;
805 }
806 if (ret)
807 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
808 else if (cdev->handler)
809 cdev->handler(cdev, cdev->private->intparm,
810 ERR_PTR(-ETIMEDOUT));
811 }
812
813 /*
814 * Got an interrupt for a basic sense.
815 */
816 static void
ccw_device_w4sense(struct ccw_device * cdev,enum dev_event dev_event)817 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
818 {
819 struct irb *irb;
820
821 irb = this_cpu_ptr(&cio_irb);
822 /* Check for unsolicited interrupt. */
823 if (scsw_stctl(&irb->scsw) ==
824 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
825 if (scsw_cc(&irb->scsw) == 1)
826 /* Basic sense hasn't started. Try again. */
827 ccw_device_do_sense(cdev, irb);
828 else {
829 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
830 "interrupt during w4sense...\n",
831 cdev->private->dev_id.ssid,
832 cdev->private->dev_id.devno);
833 if (cdev->handler)
834 cdev->handler (cdev, 0, irb);
835 }
836 return;
837 }
838 /*
839 * Check if a halt or clear has been issued in the meanwhile. If yes,
840 * only deliver the halt/clear interrupt to the device driver as if it
841 * had killed the original request.
842 */
843 if (scsw_fctl(&irb->scsw) &
844 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
845 cdev->private->flags.dosense = 0;
846 memset(&cdev->private->irb, 0, sizeof(struct irb));
847 ccw_device_accumulate_irb(cdev, irb);
848 goto call_handler;
849 }
850 /* Add basic sense info to irb. */
851 ccw_device_accumulate_basic_sense(cdev, irb);
852 if (cdev->private->flags.dosense) {
853 /* Another basic sense is needed. */
854 ccw_device_do_sense(cdev, irb);
855 return;
856 }
857 call_handler:
858 cdev->private->state = DEV_STATE_ONLINE;
859 /* In case sensing interfered with setting the device online */
860 wake_up(&cdev->private->wait_q);
861 /* Call the handler. */
862 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
863 /* Start delayed path verification. */
864 ccw_device_online_verify(cdev, 0);
865 }
866
867 static void
ccw_device_killing_irq(struct ccw_device * cdev,enum dev_event dev_event)868 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
869 {
870 ccw_device_set_timeout(cdev, 0);
871 /* Start delayed path verification. */
872 ccw_device_online_verify(cdev, 0);
873 /* OK, i/o is dead now. Call interrupt handler. */
874 if (cdev->handler)
875 cdev->handler(cdev, cdev->private->intparm,
876 ERR_PTR(cdev->private->async_kill_io_rc));
877 }
878
879 static void
ccw_device_killing_timeout(struct ccw_device * cdev,enum dev_event dev_event)880 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
881 {
882 int ret;
883
884 ret = ccw_device_cancel_halt_clear(cdev);
885 if (ret == -EBUSY) {
886 ccw_device_set_timeout(cdev, 3*HZ);
887 return;
888 }
889 /* Start delayed path verification. */
890 ccw_device_online_verify(cdev, 0);
891 if (cdev->handler)
892 cdev->handler(cdev, cdev->private->intparm,
893 ERR_PTR(cdev->private->async_kill_io_rc));
894 }
895
ccw_device_kill_io(struct ccw_device * cdev)896 void ccw_device_kill_io(struct ccw_device *cdev)
897 {
898 int ret;
899
900 ccw_device_set_timeout(cdev, 0);
901 cdev->private->iretry = 255;
902 cdev->private->async_kill_io_rc = -EIO;
903 ret = ccw_device_cancel_halt_clear(cdev);
904 if (ret == -EBUSY) {
905 ccw_device_set_timeout(cdev, 3*HZ);
906 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
907 return;
908 }
909 /* Start delayed path verification. */
910 ccw_device_online_verify(cdev, 0);
911 if (cdev->handler)
912 cdev->handler(cdev, cdev->private->intparm,
913 ERR_PTR(-EIO));
914 }
915
916 static void
ccw_device_delay_verify(struct ccw_device * cdev,enum dev_event dev_event)917 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
918 {
919 /* Start verification after current task finished. */
920 cdev->private->flags.doverify = 1;
921 }
922
923 static void
ccw_device_start_id(struct ccw_device * cdev,enum dev_event dev_event)924 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
925 {
926 struct subchannel *sch;
927
928 sch = to_subchannel(cdev->dev.parent);
929 if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
930 /* Couldn't enable the subchannel for i/o. Sick device. */
931 return;
932 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
933 ccw_device_sense_id_start(cdev);
934 }
935
ccw_device_trigger_reprobe(struct ccw_device * cdev)936 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
937 {
938 struct subchannel *sch;
939
940 if (cdev->private->state != DEV_STATE_DISCONNECTED)
941 return;
942
943 sch = to_subchannel(cdev->dev.parent);
944 /* Update some values. */
945 if (cio_update_schib(sch))
946 return;
947 /*
948 * The pim, pam, pom values may not be accurate, but they are the best
949 * we have before performing device selection :/
950 */
951 sch->lpm = sch->schib.pmcw.pam & sch->opm;
952 /*
953 * Use the initial configuration since we can't be shure that the old
954 * paths are valid.
955 */
956 io_subchannel_init_config(sch);
957 if (cio_commit_config(sch))
958 return;
959
960 /* We should also udate ssd info, but this has to wait. */
961 /* Check if this is another device which appeared on the same sch. */
962 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
963 css_schedule_eval(sch->schid);
964 else
965 ccw_device_start_id(cdev, 0);
966 }
967
ccw_device_disabled_irq(struct ccw_device * cdev,enum dev_event dev_event)968 static void ccw_device_disabled_irq(struct ccw_device *cdev,
969 enum dev_event dev_event)
970 {
971 struct subchannel *sch;
972
973 sch = to_subchannel(cdev->dev.parent);
974 /*
975 * An interrupt in a disabled state means a previous disable was not
976 * successful - should not happen, but we try to disable again.
977 */
978 cio_disable_subchannel(sch);
979 }
980
981 static void
ccw_device_change_cmfstate(struct ccw_device * cdev,enum dev_event dev_event)982 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
983 {
984 retry_set_schib(cdev);
985 cdev->private->state = DEV_STATE_ONLINE;
986 dev_fsm_event(cdev, dev_event);
987 }
988
ccw_device_update_cmfblock(struct ccw_device * cdev,enum dev_event dev_event)989 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
990 enum dev_event dev_event)
991 {
992 cmf_retry_copy_block(cdev);
993 cdev->private->state = DEV_STATE_ONLINE;
994 dev_fsm_event(cdev, dev_event);
995 }
996
997 static void
ccw_device_quiesce_done(struct ccw_device * cdev,enum dev_event dev_event)998 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
999 {
1000 ccw_device_set_timeout(cdev, 0);
1001 cdev->private->state = DEV_STATE_NOT_OPER;
1002 wake_up(&cdev->private->wait_q);
1003 }
1004
1005 static void
ccw_device_quiesce_timeout(struct ccw_device * cdev,enum dev_event dev_event)1006 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1007 {
1008 int ret;
1009
1010 ret = ccw_device_cancel_halt_clear(cdev);
1011 if (ret == -EBUSY) {
1012 ccw_device_set_timeout(cdev, HZ/10);
1013 } else {
1014 cdev->private->state = DEV_STATE_NOT_OPER;
1015 wake_up(&cdev->private->wait_q);
1016 }
1017 }
1018
1019 /*
1020 * No operation action. This is used e.g. to ignore a timeout event in
1021 * state offline.
1022 */
1023 static void
ccw_device_nop(struct ccw_device * cdev,enum dev_event dev_event)1024 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1025 {
1026 }
1027
1028 /*
1029 * device statemachine
1030 */
1031 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1032 [DEV_STATE_NOT_OPER] = {
1033 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1034 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1035 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1036 [DEV_EVENT_VERIFY] = ccw_device_nop,
1037 },
1038 [DEV_STATE_SENSE_ID] = {
1039 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1040 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1041 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1042 [DEV_EVENT_VERIFY] = ccw_device_nop,
1043 },
1044 [DEV_STATE_OFFLINE] = {
1045 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1046 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1047 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1048 [DEV_EVENT_VERIFY] = ccw_device_offline_verify,
1049 },
1050 [DEV_STATE_VERIFY] = {
1051 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1052 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1053 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1054 [DEV_EVENT_VERIFY] = ccw_device_delay_verify,
1055 },
1056 [DEV_STATE_ONLINE] = {
1057 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1058 [DEV_EVENT_INTERRUPT] = ccw_device_irq,
1059 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
1060 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1061 },
1062 [DEV_STATE_W4SENSE] = {
1063 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1064 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
1065 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1066 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1067 },
1068 [DEV_STATE_DISBAND_PGID] = {
1069 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1070 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1071 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1072 [DEV_EVENT_VERIFY] = ccw_device_nop,
1073 },
1074 [DEV_STATE_BOXED] = {
1075 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1076 [DEV_EVENT_INTERRUPT] = ccw_device_nop,
1077 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1078 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
1079 },
1080 /* states to wait for i/o completion before doing something */
1081 [DEV_STATE_TIMEOUT_KILL] = {
1082 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1083 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
1084 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
1085 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
1086 },
1087 [DEV_STATE_QUIESCE] = {
1088 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
1089 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
1090 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
1091 [DEV_EVENT_VERIFY] = ccw_device_nop,
1092 },
1093 /* special states for devices gone not operational */
1094 [DEV_STATE_DISCONNECTED] = {
1095 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1096 [DEV_EVENT_INTERRUPT] = ccw_device_start_id,
1097 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1098 [DEV_EVENT_VERIFY] = ccw_device_start_id,
1099 },
1100 [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1101 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1102 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1103 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1104 [DEV_EVENT_VERIFY] = ccw_device_nop,
1105 },
1106 [DEV_STATE_CMFCHANGE] = {
1107 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate,
1108 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate,
1109 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate,
1110 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate,
1111 },
1112 [DEV_STATE_CMFUPDATE] = {
1113 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
1114 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
1115 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
1116 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
1117 },
1118 [DEV_STATE_STEAL_LOCK] = {
1119 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1120 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1121 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1122 [DEV_EVENT_VERIFY] = ccw_device_nop,
1123 },
1124 };
1125
1126 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
1127