1 // SPDX-License-Identifier: GPL-2.0
2 /*
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/io.h>
13 #include <linux/jiffies.h>
14 #include <linux/string.h>
15
16 #include <asm/ccwdev.h>
17 #include <asm/cio.h>
18 #include <asm/chpid.h>
19
20 #include "cio.h"
21 #include "cio_debug.h"
22 #include "css.h"
23 #include "device.h"
24 #include "chsc.h"
25 #include "ioasm.h"
26 #include "chp.h"
27
28 static int timeout_log_enabled;
29
ccw_timeout_log_setup(char * unused)30 static int __init ccw_timeout_log_setup(char *unused)
31 {
32 timeout_log_enabled = 1;
33 return 1;
34 }
35
36 __setup("ccw_timeout_log", ccw_timeout_log_setup);
37
ccw_timeout_log(struct ccw_device * cdev)38 static void ccw_timeout_log(struct ccw_device *cdev)
39 {
40 struct schib schib;
41 struct subchannel *sch;
42 struct io_subchannel_private *private;
43 union orb *orb;
44 int cc;
45
46 sch = to_subchannel(cdev->dev.parent);
47 private = to_io_private(sch);
48 orb = &private->orb;
49 cc = stsch(sch->schid, &schib);
50
51 printk(KERN_WARNING "cio: ccw device timeout occurred at %lx, "
52 "device information:\n", get_tod_clock());
53 printk(KERN_WARNING "cio: orb:\n");
54 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
55 orb, sizeof(*orb), 0);
56 printk(KERN_WARNING "cio: ccw device bus id: %s\n",
57 dev_name(&cdev->dev));
58 printk(KERN_WARNING "cio: subchannel bus id: %s\n",
59 dev_name(&sch->dev));
60 printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
61 "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
62
63 if (orb->tm.b) {
64 printk(KERN_WARNING "cio: orb indicates transport mode\n");
65 printk(KERN_WARNING "cio: last tcw:\n");
66 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
67 dma32_to_virt(orb->tm.tcw),
68 sizeof(struct tcw), 0);
69 } else {
70 printk(KERN_WARNING "cio: orb indicates command mode\n");
71 if (dma32_to_virt(orb->cmd.cpa) ==
72 &private->dma_area->sense_ccw ||
73 dma32_to_virt(orb->cmd.cpa) ==
74 cdev->private->dma_area->iccws)
75 printk(KERN_WARNING "cio: last channel program "
76 "(intern):\n");
77 else
78 printk(KERN_WARNING "cio: last channel program:\n");
79
80 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
81 dma32_to_virt(orb->cmd.cpa),
82 sizeof(struct ccw1), 0);
83 }
84 printk(KERN_WARNING "cio: ccw device state: %d\n",
85 cdev->private->state);
86 printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
87 printk(KERN_WARNING "cio: schib:\n");
88 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
89 &schib, sizeof(schib), 0);
90 printk(KERN_WARNING "cio: ccw device flags:\n");
91 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
92 &cdev->private->flags, sizeof(cdev->private->flags), 0);
93 }
94
95 /*
96 * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
97 */
98 void
ccw_device_timeout(struct timer_list * t)99 ccw_device_timeout(struct timer_list *t)
100 {
101 struct ccw_device_private *priv = from_timer(priv, t, timer);
102 struct ccw_device *cdev = priv->cdev;
103
104 spin_lock_irq(cdev->ccwlock);
105 if (timeout_log_enabled)
106 ccw_timeout_log(cdev);
107 dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
108 spin_unlock_irq(cdev->ccwlock);
109 }
110
111 /*
112 * Set timeout
113 */
114 void
ccw_device_set_timeout(struct ccw_device * cdev,int expires)115 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
116 {
117 if (expires == 0)
118 del_timer(&cdev->private->timer);
119 else
120 mod_timer(&cdev->private->timer, jiffies + expires);
121 }
122
123 int
ccw_device_cancel_halt_clear(struct ccw_device * cdev)124 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
125 {
126 struct subchannel *sch;
127 int ret;
128
129 sch = to_subchannel(cdev->dev.parent);
130 ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
131
132 if (ret == -EIO)
133 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
134 cdev->private->dev_id.ssid,
135 cdev->private->dev_id.devno);
136
137 return ret;
138 }
139
ccw_device_update_sense_data(struct ccw_device * cdev)140 void ccw_device_update_sense_data(struct ccw_device *cdev)
141 {
142 memset(&cdev->id, 0, sizeof(cdev->id));
143 cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type;
144 cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model;
145 cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type;
146 cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model;
147 }
148
ccw_device_test_sense_data(struct ccw_device * cdev)149 int ccw_device_test_sense_data(struct ccw_device *cdev)
150 {
151 return cdev->id.cu_type ==
152 cdev->private->dma_area->senseid.cu_type &&
153 cdev->id.cu_model ==
154 cdev->private->dma_area->senseid.cu_model &&
155 cdev->id.dev_type ==
156 cdev->private->dma_area->senseid.dev_type &&
157 cdev->id.dev_model ==
158 cdev->private->dma_area->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 switch (state) {
223 case DEV_STATE_NOT_OPER:
224 break;
225 case DEV_STATE_OFFLINE:
226 if (!cdev->online) {
227 ccw_device_update_sense_data(cdev);
228 break;
229 }
230 cdev->private->state = DEV_STATE_OFFLINE;
231 cdev->private->flags.recog_done = 1;
232 if (ccw_device_test_sense_data(cdev)) {
233 cdev->private->flags.donotify = 1;
234 ccw_device_online(cdev);
235 wake_up(&cdev->private->wait_q);
236 } else {
237 ccw_device_update_sense_data(cdev);
238 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
239 }
240 return;
241 case DEV_STATE_BOXED:
242 if (cdev->id.cu_type != 0) { /* device was recognized before */
243 cdev->private->flags.recog_done = 1;
244 cdev->private->state = DEV_STATE_BOXED;
245 wake_up(&cdev->private->wait_q);
246 return;
247 }
248 break;
249 }
250 cdev->private->state = state;
251 io_subchannel_recog_done(cdev);
252 wake_up(&cdev->private->wait_q);
253 }
254
255 /*
256 * Function called from device_id.c after sense id has completed.
257 */
258 void
ccw_device_sense_id_done(struct ccw_device * cdev,int err)259 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
260 {
261 switch (err) {
262 case 0:
263 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
264 break;
265 case -ETIME: /* Sense id stopped by timeout. */
266 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
267 break;
268 default:
269 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
270 break;
271 }
272 }
273
274 /**
275 * ccw_device_notify() - inform the device's driver about an event
276 * @cdev: device for which an event occurred
277 * @event: event that occurred
278 *
279 * Returns:
280 * -%EINVAL if the device is offline or has no driver.
281 * -%EOPNOTSUPP if the device's driver has no notifier registered.
282 * %NOTIFY_OK if the driver wants to keep the device.
283 * %NOTIFY_BAD if the driver doesn't want to keep the device.
284 */
ccw_device_notify(struct ccw_device * cdev,int event)285 int ccw_device_notify(struct ccw_device *cdev, int event)
286 {
287 int ret = -EINVAL;
288
289 if (!cdev->drv)
290 goto out;
291 if (!cdev->online)
292 goto out;
293 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
294 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
295 event);
296 if (!cdev->drv->notify) {
297 ret = -EOPNOTSUPP;
298 goto out;
299 }
300 if (cdev->drv->notify(cdev, event))
301 ret = NOTIFY_OK;
302 else
303 ret = NOTIFY_BAD;
304 out:
305 return ret;
306 }
307
ccw_device_oper_notify(struct ccw_device * cdev)308 static void ccw_device_oper_notify(struct ccw_device *cdev)
309 {
310 struct subchannel *sch = to_subchannel(cdev->dev.parent);
311
312 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
313 /* Re-enable channel measurements, if needed. */
314 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
315 /* Save indication for new paths. */
316 cdev->private->path_new_mask = sch->vpm;
317 return;
318 }
319 /* Driver doesn't want device back. */
320 ccw_device_set_notoper(cdev);
321 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
322 }
323
324 /*
325 * Finished with online/offline processing.
326 */
327 static void
ccw_device_done(struct ccw_device * cdev,int state)328 ccw_device_done(struct ccw_device *cdev, int state)
329 {
330 struct subchannel *sch;
331
332 sch = to_subchannel(cdev->dev.parent);
333
334 ccw_device_set_timeout(cdev, 0);
335
336 if (state != DEV_STATE_ONLINE)
337 cio_disable_subchannel(sch);
338
339 /* Reset device status. */
340 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
341
342 cdev->private->state = state;
343
344 switch (state) {
345 case DEV_STATE_BOXED:
346 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
347 cdev->private->dev_id.devno, sch->schid.sch_no);
348 if (cdev->online &&
349 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
350 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
351 cdev->private->flags.donotify = 0;
352 break;
353 case DEV_STATE_NOT_OPER:
354 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
355 cdev->private->dev_id.devno, sch->schid.sch_no);
356 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
357 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
358 else
359 ccw_device_set_disconnected(cdev);
360 cdev->private->flags.donotify = 0;
361 break;
362 case DEV_STATE_DISCONNECTED:
363 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
364 "%04x\n", cdev->private->dev_id.devno,
365 sch->schid.sch_no);
366 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
367 cdev->private->state = DEV_STATE_NOT_OPER;
368 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
369 } else
370 ccw_device_set_disconnected(cdev);
371 cdev->private->flags.donotify = 0;
372 break;
373 default:
374 break;
375 }
376
377 if (cdev->private->flags.donotify) {
378 cdev->private->flags.donotify = 0;
379 ccw_device_oper_notify(cdev);
380 }
381 wake_up(&cdev->private->wait_q);
382 }
383
384 /*
385 * Start device recognition.
386 */
ccw_device_recognition(struct ccw_device * cdev)387 void ccw_device_recognition(struct ccw_device *cdev)
388 {
389 struct subchannel *sch = to_subchannel(cdev->dev.parent);
390
391 /*
392 * We used to start here with a sense pgid to find out whether a device
393 * is locked by someone else. Unfortunately, the sense pgid command
394 * code has other meanings on devices predating the path grouping
395 * algorithm, so we start with sense id and box the device after an
396 * timeout (or if sense pgid during path verification detects the device
397 * is locked, as may happen on newer devices).
398 */
399 cdev->private->flags.recog_done = 0;
400 cdev->private->state = DEV_STATE_SENSE_ID;
401 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch))) {
402 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
403 return;
404 }
405 ccw_device_sense_id_start(cdev);
406 }
407
408 /*
409 * Handle events for states that use the ccw request infrastructure.
410 */
ccw_device_request_event(struct ccw_device * cdev,enum dev_event e)411 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
412 {
413 switch (e) {
414 case DEV_EVENT_NOTOPER:
415 ccw_request_notoper(cdev);
416 break;
417 case DEV_EVENT_INTERRUPT:
418 ccw_request_handler(cdev);
419 break;
420 case DEV_EVENT_TIMEOUT:
421 ccw_request_timeout(cdev);
422 break;
423 default:
424 break;
425 }
426 }
427
ccw_device_report_path_events(struct ccw_device * cdev)428 static void ccw_device_report_path_events(struct ccw_device *cdev)
429 {
430 struct subchannel *sch = to_subchannel(cdev->dev.parent);
431 int path_event[8];
432 int chp, mask;
433
434 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
435 path_event[chp] = PE_NONE;
436 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
437 path_event[chp] |= PE_PATH_GONE;
438 if (mask & cdev->private->path_new_mask & sch->vpm)
439 path_event[chp] |= PE_PATH_AVAILABLE;
440 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
441 path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
442 }
443 if (cdev->online && cdev->drv->path_event)
444 cdev->drv->path_event(cdev, path_event);
445 }
446
ccw_device_reset_path_events(struct ccw_device * cdev)447 static void ccw_device_reset_path_events(struct ccw_device *cdev)
448 {
449 cdev->private->path_gone_mask = 0;
450 cdev->private->path_new_mask = 0;
451 cdev->private->pgid_reset_mask = 0;
452 }
453
create_fake_irb(struct irb * irb,int type)454 static void create_fake_irb(struct irb *irb, int type)
455 {
456 memset(irb, 0, sizeof(*irb));
457 if (type == FAKE_CMD_IRB) {
458 struct cmd_scsw *scsw = &irb->scsw.cmd;
459 scsw->cc = 1;
460 scsw->fctl = SCSW_FCTL_START_FUNC;
461 scsw->actl = SCSW_ACTL_START_PEND;
462 scsw->stctl = SCSW_STCTL_STATUS_PEND;
463 } else if (type == FAKE_TM_IRB) {
464 struct tm_scsw *scsw = &irb->scsw.tm;
465 scsw->x = 1;
466 scsw->cc = 1;
467 scsw->fctl = SCSW_FCTL_START_FUNC;
468 scsw->actl = SCSW_ACTL_START_PEND;
469 scsw->stctl = SCSW_STCTL_STATUS_PEND;
470 }
471 }
472
ccw_device_handle_broken_paths(struct ccw_device * cdev)473 static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
474 {
475 struct subchannel *sch = to_subchannel(cdev->dev.parent);
476 u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
477
478 if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
479 ccw_device_schedule_recovery();
480
481 cdev->private->path_broken_mask = broken_paths;
482 }
483
ccw_device_verify_done(struct ccw_device * cdev,int err)484 void ccw_device_verify_done(struct ccw_device *cdev, int err)
485 {
486 struct subchannel *sch;
487
488 sch = to_subchannel(cdev->dev.parent);
489 /* Update schib - pom may have changed. */
490 if (cio_update_schib(sch)) {
491 err = -ENODEV;
492 goto callback;
493 }
494 /* Update lpm with verified path mask. */
495 sch->lpm = sch->vpm;
496 /* Repeat path verification? */
497 if (cdev->private->flags.doverify) {
498 ccw_device_verify_start(cdev);
499 return;
500 }
501 callback:
502 switch (err) {
503 case 0:
504 ccw_device_done(cdev, DEV_STATE_ONLINE);
505 /* Deliver fake irb to device driver, if needed. */
506 if (cdev->private->flags.fake_irb) {
507 CIO_MSG_EVENT(2, "fakeirb: deliver device 0.%x.%04x intparm %lx type=%d\n",
508 cdev->private->dev_id.ssid,
509 cdev->private->dev_id.devno,
510 cdev->private->intparm,
511 cdev->private->flags.fake_irb);
512 create_fake_irb(&cdev->private->dma_area->irb,
513 cdev->private->flags.fake_irb);
514 cdev->private->flags.fake_irb = 0;
515 if (cdev->handler)
516 cdev->handler(cdev, cdev->private->intparm,
517 &cdev->private->dma_area->irb);
518 memset(&cdev->private->dma_area->irb, 0,
519 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)virt_to_phys(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->dma_area->irb.scsw) &
677 SCSW_STCTL_STATUS_PEND)) {
678 /*
679 * No final status yet or final status not yet delivered
680 * to the device driver. Can't do path verification now,
681 * delay until final status was delivered.
682 */
683 cdev->private->flags.doverify = 1;
684 return;
685 }
686 /* Device is idle, we can do the path verification. */
687 cdev->private->state = DEV_STATE_VERIFY;
688 ccw_device_verify_start(cdev);
689 }
690
691 /*
692 * Handle path verification event in boxed state.
693 */
ccw_device_boxed_verify(struct ccw_device * cdev,enum dev_event dev_event)694 static void ccw_device_boxed_verify(struct ccw_device *cdev,
695 enum dev_event dev_event)
696 {
697 struct subchannel *sch = to_subchannel(cdev->dev.parent);
698
699 if (cdev->online) {
700 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)))
701 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
702 else
703 ccw_device_online_verify(cdev, dev_event);
704 } else
705 css_schedule_eval(sch->schid);
706 }
707
708 /*
709 * Pass interrupt to device driver.
710 */
ccw_device_call_handler(struct ccw_device * cdev)711 static int ccw_device_call_handler(struct ccw_device *cdev)
712 {
713 unsigned int stctl;
714 int ending_status;
715
716 /*
717 * we allow for the device action handler if .
718 * - we received ending status
719 * - the action handler requested to see all interrupts
720 * - we received an intermediate status
721 * - fast notification was requested (primary status)
722 * - unsolicited interrupts
723 */
724 stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
725 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
726 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
727 (stctl == SCSW_STCTL_STATUS_PEND);
728 if (!ending_status &&
729 !cdev->private->options.repall &&
730 !(stctl & SCSW_STCTL_INTER_STATUS) &&
731 !(cdev->private->options.fast &&
732 (stctl & SCSW_STCTL_PRIM_STATUS)))
733 return 0;
734
735 if (ending_status)
736 ccw_device_set_timeout(cdev, 0);
737
738 if (cdev->handler)
739 cdev->handler(cdev, cdev->private->intparm,
740 &cdev->private->dma_area->irb);
741
742 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
743 return 1;
744 }
745
746 /*
747 * Got an interrupt for a normal io (state online).
748 */
749 static void
ccw_device_irq(struct ccw_device * cdev,enum dev_event dev_event)750 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
751 {
752 struct irb *irb;
753 int is_cmd;
754
755 irb = this_cpu_ptr(&cio_irb);
756 is_cmd = !scsw_is_tm(&irb->scsw);
757 /* Check for unsolicited interrupt. */
758 if (!scsw_is_solicited(&irb->scsw)) {
759 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
760 !irb->esw.esw0.erw.cons) {
761 /* Unit check but no sense data. Need basic sense. */
762 if (ccw_device_do_sense(cdev, irb) != 0)
763 goto call_handler_unsol;
764 memcpy(&cdev->private->dma_area->irb, irb,
765 sizeof(struct irb));
766 cdev->private->state = DEV_STATE_W4SENSE;
767 cdev->private->intparm = 0;
768 return;
769 }
770 call_handler_unsol:
771 if (cdev->handler)
772 cdev->handler (cdev, 0, irb);
773 if (cdev->private->flags.doverify)
774 ccw_device_online_verify(cdev, 0);
775 return;
776 }
777 /* Accumulate status and find out if a basic sense is needed. */
778 ccw_device_accumulate_irb(cdev, irb);
779 if (is_cmd && cdev->private->flags.dosense) {
780 if (ccw_device_do_sense(cdev, irb) == 0) {
781 cdev->private->state = DEV_STATE_W4SENSE;
782 }
783 return;
784 }
785 /* Call the handler. */
786 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
787 /* Start delayed path verification. */
788 ccw_device_online_verify(cdev, 0);
789 }
790
791 /*
792 * Got an timeout in online state.
793 */
794 static void
ccw_device_online_timeout(struct ccw_device * cdev,enum dev_event dev_event)795 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
796 {
797 int ret;
798
799 ccw_device_set_timeout(cdev, 0);
800 cdev->private->iretry = 255;
801 cdev->private->async_kill_io_rc = -ETIMEDOUT;
802 ret = ccw_device_cancel_halt_clear(cdev);
803 if (ret == -EBUSY) {
804 ccw_device_set_timeout(cdev, 3*HZ);
805 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
806 return;
807 }
808 if (ret)
809 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
810 else if (cdev->handler)
811 cdev->handler(cdev, cdev->private->intparm,
812 ERR_PTR(-ETIMEDOUT));
813 }
814
815 /*
816 * Got an interrupt for a basic sense.
817 */
818 static void
ccw_device_w4sense(struct ccw_device * cdev,enum dev_event dev_event)819 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
820 {
821 struct irb *irb;
822
823 irb = this_cpu_ptr(&cio_irb);
824 /* Check for unsolicited interrupt. */
825 if (scsw_stctl(&irb->scsw) ==
826 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
827 if (scsw_cc(&irb->scsw) == 1)
828 /* Basic sense hasn't started. Try again. */
829 ccw_device_do_sense(cdev, irb);
830 else {
831 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
832 "interrupt during w4sense...\n",
833 cdev->private->dev_id.ssid,
834 cdev->private->dev_id.devno);
835 if (cdev->handler)
836 cdev->handler (cdev, 0, irb);
837 }
838 return;
839 }
840 /*
841 * Check if a halt or clear has been issued in the meanwhile. If yes,
842 * only deliver the halt/clear interrupt to the device driver as if it
843 * had killed the original request.
844 */
845 if (scsw_fctl(&irb->scsw) &
846 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
847 cdev->private->flags.dosense = 0;
848 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
849 ccw_device_accumulate_irb(cdev, irb);
850 goto call_handler;
851 }
852 /* Add basic sense info to irb. */
853 ccw_device_accumulate_basic_sense(cdev, irb);
854 if (cdev->private->flags.dosense) {
855 /* Another basic sense is needed. */
856 ccw_device_do_sense(cdev, irb);
857 return;
858 }
859 call_handler:
860 cdev->private->state = DEV_STATE_ONLINE;
861 /* In case sensing interfered with setting the device online */
862 wake_up(&cdev->private->wait_q);
863 /* Call the handler. */
864 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
865 /* Start delayed path verification. */
866 ccw_device_online_verify(cdev, 0);
867 }
868
869 static void
ccw_device_killing_irq(struct ccw_device * cdev,enum dev_event dev_event)870 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
871 {
872 ccw_device_set_timeout(cdev, 0);
873 /* Start delayed path verification. */
874 ccw_device_online_verify(cdev, 0);
875 /* OK, i/o is dead now. Call interrupt handler. */
876 if (cdev->handler)
877 cdev->handler(cdev, cdev->private->intparm,
878 ERR_PTR(cdev->private->async_kill_io_rc));
879 }
880
881 static void
ccw_device_killing_timeout(struct ccw_device * cdev,enum dev_event dev_event)882 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
883 {
884 int ret;
885
886 ret = ccw_device_cancel_halt_clear(cdev);
887 if (ret == -EBUSY) {
888 ccw_device_set_timeout(cdev, 3*HZ);
889 return;
890 }
891 /* Start delayed path verification. */
892 ccw_device_online_verify(cdev, 0);
893 if (cdev->handler)
894 cdev->handler(cdev, cdev->private->intparm,
895 ERR_PTR(cdev->private->async_kill_io_rc));
896 }
897
ccw_device_kill_io(struct ccw_device * cdev)898 void ccw_device_kill_io(struct ccw_device *cdev)
899 {
900 int ret;
901
902 ccw_device_set_timeout(cdev, 0);
903 cdev->private->iretry = 255;
904 cdev->private->async_kill_io_rc = -EIO;
905 ret = ccw_device_cancel_halt_clear(cdev);
906 if (ret == -EBUSY) {
907 ccw_device_set_timeout(cdev, 3*HZ);
908 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
909 return;
910 }
911 /* Start delayed path verification. */
912 ccw_device_online_verify(cdev, 0);
913 if (cdev->handler)
914 cdev->handler(cdev, cdev->private->intparm,
915 ERR_PTR(-EIO));
916 }
917
918 static void
ccw_device_delay_verify(struct ccw_device * cdev,enum dev_event dev_event)919 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
920 {
921 /* Start verification after current task finished. */
922 cdev->private->flags.doverify = 1;
923 }
924
925 static void
ccw_device_start_id(struct ccw_device * cdev,enum dev_event dev_event)926 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
927 {
928 struct subchannel *sch;
929
930 sch = to_subchannel(cdev->dev.parent);
931 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)) != 0)
932 /* Couldn't enable the subchannel for i/o. Sick device. */
933 return;
934 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
935 ccw_device_sense_id_start(cdev);
936 }
937
ccw_device_trigger_reprobe(struct ccw_device * cdev)938 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
939 {
940 struct subchannel *sch;
941
942 if (cdev->private->state != DEV_STATE_DISCONNECTED)
943 return;
944
945 sch = to_subchannel(cdev->dev.parent);
946 /* Update some values. */
947 if (cio_update_schib(sch))
948 return;
949 /*
950 * The pim, pam, pom values may not be accurate, but they are the best
951 * we have before performing device selection :/
952 */
953 sch->lpm = sch->schib.pmcw.pam & sch->opm;
954 /*
955 * Use the initial configuration since we can't be sure that the old
956 * paths are valid.
957 */
958 io_subchannel_init_config(sch);
959 if (cio_commit_config(sch))
960 return;
961
962 /* We should also udate ssd info, but this has to wait. */
963 /* Check if this is another device which appeared on the same sch. */
964 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
965 css_schedule_eval(sch->schid);
966 else
967 ccw_device_start_id(cdev, 0);
968 }
969
ccw_device_disabled_irq(struct ccw_device * cdev,enum dev_event dev_event)970 static void ccw_device_disabled_irq(struct ccw_device *cdev,
971 enum dev_event dev_event)
972 {
973 struct subchannel *sch;
974
975 sch = to_subchannel(cdev->dev.parent);
976 /*
977 * An interrupt in a disabled state means a previous disable was not
978 * successful - should not happen, but we try to disable again.
979 */
980 cio_disable_subchannel(sch);
981 }
982
983 static void
ccw_device_change_cmfstate(struct ccw_device * cdev,enum dev_event dev_event)984 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
985 {
986 retry_set_schib(cdev);
987 cdev->private->state = DEV_STATE_ONLINE;
988 dev_fsm_event(cdev, dev_event);
989 }
990
ccw_device_update_cmfblock(struct ccw_device * cdev,enum dev_event dev_event)991 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
992 enum dev_event dev_event)
993 {
994 cmf_retry_copy_block(cdev);
995 cdev->private->state = DEV_STATE_ONLINE;
996 dev_fsm_event(cdev, dev_event);
997 }
998
999 static void
ccw_device_quiesce_done(struct ccw_device * cdev,enum dev_event dev_event)1000 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1001 {
1002 ccw_device_set_timeout(cdev, 0);
1003 cdev->private->state = DEV_STATE_NOT_OPER;
1004 wake_up(&cdev->private->wait_q);
1005 }
1006
1007 static void
ccw_device_quiesce_timeout(struct ccw_device * cdev,enum dev_event dev_event)1008 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1009 {
1010 int ret;
1011
1012 ret = ccw_device_cancel_halt_clear(cdev);
1013 if (ret == -EBUSY) {
1014 ccw_device_set_timeout(cdev, HZ/10);
1015 } else {
1016 cdev->private->state = DEV_STATE_NOT_OPER;
1017 wake_up(&cdev->private->wait_q);
1018 }
1019 }
1020
1021 /*
1022 * No operation action. This is used e.g. to ignore a timeout event in
1023 * state offline.
1024 */
1025 static void
ccw_device_nop(struct ccw_device * cdev,enum dev_event dev_event)1026 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1027 {
1028 }
1029
1030 /*
1031 * device statemachine
1032 */
1033 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1034 [DEV_STATE_NOT_OPER] = {
1035 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1036 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1037 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1038 [DEV_EVENT_VERIFY] = ccw_device_nop,
1039 },
1040 [DEV_STATE_SENSE_ID] = {
1041 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1042 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1043 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1044 [DEV_EVENT_VERIFY] = ccw_device_nop,
1045 },
1046 [DEV_STATE_OFFLINE] = {
1047 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1048 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1049 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1050 [DEV_EVENT_VERIFY] = ccw_device_offline_verify,
1051 },
1052 [DEV_STATE_VERIFY] = {
1053 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1054 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1055 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1056 [DEV_EVENT_VERIFY] = ccw_device_delay_verify,
1057 },
1058 [DEV_STATE_ONLINE] = {
1059 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1060 [DEV_EVENT_INTERRUPT] = ccw_device_irq,
1061 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
1062 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1063 },
1064 [DEV_STATE_W4SENSE] = {
1065 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1066 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
1067 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1068 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1069 },
1070 [DEV_STATE_DISBAND_PGID] = {
1071 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1072 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1073 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1074 [DEV_EVENT_VERIFY] = ccw_device_nop,
1075 },
1076 [DEV_STATE_BOXED] = {
1077 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1078 [DEV_EVENT_INTERRUPT] = ccw_device_nop,
1079 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1080 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
1081 },
1082 /* states to wait for i/o completion before doing something */
1083 [DEV_STATE_TIMEOUT_KILL] = {
1084 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1085 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
1086 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
1087 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
1088 },
1089 [DEV_STATE_QUIESCE] = {
1090 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
1091 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
1092 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
1093 [DEV_EVENT_VERIFY] = ccw_device_nop,
1094 },
1095 /* special states for devices gone not operational */
1096 [DEV_STATE_DISCONNECTED] = {
1097 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1098 [DEV_EVENT_INTERRUPT] = ccw_device_start_id,
1099 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1100 [DEV_EVENT_VERIFY] = ccw_device_start_id,
1101 },
1102 [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1103 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1104 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1105 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1106 [DEV_EVENT_VERIFY] = ccw_device_nop,
1107 },
1108 [DEV_STATE_CMFCHANGE] = {
1109 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate,
1110 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate,
1111 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate,
1112 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate,
1113 },
1114 [DEV_STATE_CMFUPDATE] = {
1115 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
1116 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
1117 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
1118 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
1119 },
1120 [DEV_STATE_STEAL_LOCK] = {
1121 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1122 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1123 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1124 [DEV_EVENT_VERIFY] = ccw_device_nop,
1125 },
1126 };
1127
1128 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
1129