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 phys_to_virt(orb->tm.tcw),
68 sizeof(struct tcw), 0);
69 } else {
70 printk(KERN_WARNING "cio: orb indicates command mode\n");
71 if ((void *)(addr_t)orb->cmd.cpa ==
72 &private->dma_area->sense_ccw ||
73 (void *)(addr_t)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 phys_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 create_fake_irb(&cdev->private->dma_area->irb,
508 cdev->private->flags.fake_irb);
509 cdev->private->flags.fake_irb = 0;
510 if (cdev->handler)
511 cdev->handler(cdev, cdev->private->intparm,
512 &cdev->private->dma_area->irb);
513 memset(&cdev->private->dma_area->irb, 0,
514 sizeof(struct irb));
515 }
516 ccw_device_report_path_events(cdev);
517 ccw_device_handle_broken_paths(cdev);
518 break;
519 case -ETIME:
520 case -EUSERS:
521 /* Reset oper notify indication after verify error. */
522 cdev->private->flags.donotify = 0;
523 ccw_device_done(cdev, DEV_STATE_BOXED);
524 break;
525 case -EACCES:
526 /* Reset oper notify indication after verify error. */
527 cdev->private->flags.donotify = 0;
528 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
529 break;
530 default:
531 /* Reset oper notify indication after verify error. */
532 cdev->private->flags.donotify = 0;
533 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
534 break;
535 }
536 ccw_device_reset_path_events(cdev);
537 }
538
539 /*
540 * Get device online.
541 */
542 int
ccw_device_online(struct ccw_device * cdev)543 ccw_device_online(struct ccw_device *cdev)
544 {
545 struct subchannel *sch;
546 int ret;
547
548 if ((cdev->private->state != DEV_STATE_OFFLINE) &&
549 (cdev->private->state != DEV_STATE_BOXED))
550 return -EINVAL;
551 sch = to_subchannel(cdev->dev.parent);
552 ret = cio_enable_subchannel(sch, (u32)virt_to_phys(sch));
553 if (ret != 0) {
554 /* Couldn't enable the subchannel for i/o. Sick device. */
555 if (ret == -ENODEV)
556 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
557 return ret;
558 }
559 /* Start initial path verification. */
560 cdev->private->state = DEV_STATE_VERIFY;
561 ccw_device_verify_start(cdev);
562 return 0;
563 }
564
565 void
ccw_device_disband_done(struct ccw_device * cdev,int err)566 ccw_device_disband_done(struct ccw_device *cdev, int err)
567 {
568 switch (err) {
569 case 0:
570 ccw_device_done(cdev, DEV_STATE_OFFLINE);
571 break;
572 case -ETIME:
573 ccw_device_done(cdev, DEV_STATE_BOXED);
574 break;
575 default:
576 cdev->private->flags.donotify = 0;
577 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
578 break;
579 }
580 }
581
582 /*
583 * Shutdown device.
584 */
585 int
ccw_device_offline(struct ccw_device * cdev)586 ccw_device_offline(struct ccw_device *cdev)
587 {
588 struct subchannel *sch;
589
590 /* Allow ccw_device_offline while disconnected. */
591 if (cdev->private->state == DEV_STATE_DISCONNECTED ||
592 cdev->private->state == DEV_STATE_NOT_OPER) {
593 cdev->private->flags.donotify = 0;
594 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
595 return 0;
596 }
597 if (cdev->private->state == DEV_STATE_BOXED) {
598 ccw_device_done(cdev, DEV_STATE_BOXED);
599 return 0;
600 }
601 if (ccw_device_is_orphan(cdev)) {
602 ccw_device_done(cdev, DEV_STATE_OFFLINE);
603 return 0;
604 }
605 sch = to_subchannel(cdev->dev.parent);
606 if (cio_update_schib(sch))
607 return -ENODEV;
608 if (scsw_actl(&sch->schib.scsw) != 0)
609 return -EBUSY;
610 if (cdev->private->state != DEV_STATE_ONLINE)
611 return -EINVAL;
612 /* Are we doing path grouping? */
613 if (!cdev->private->flags.pgroup) {
614 /* No, set state offline immediately. */
615 ccw_device_done(cdev, DEV_STATE_OFFLINE);
616 return 0;
617 }
618 /* Start Set Path Group commands. */
619 cdev->private->state = DEV_STATE_DISBAND_PGID;
620 ccw_device_disband_start(cdev);
621 return 0;
622 }
623
624 /*
625 * Handle not operational event in non-special state.
626 */
ccw_device_generic_notoper(struct ccw_device * cdev,enum dev_event dev_event)627 static void ccw_device_generic_notoper(struct ccw_device *cdev,
628 enum dev_event dev_event)
629 {
630 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
631 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
632 else
633 ccw_device_set_disconnected(cdev);
634 }
635
636 /*
637 * Handle path verification event in offline state.
638 */
ccw_device_offline_verify(struct ccw_device * cdev,enum dev_event dev_event)639 static void ccw_device_offline_verify(struct ccw_device *cdev,
640 enum dev_event dev_event)
641 {
642 struct subchannel *sch = to_subchannel(cdev->dev.parent);
643
644 css_schedule_eval(sch->schid);
645 }
646
647 /*
648 * Handle path verification event.
649 */
650 static void
ccw_device_online_verify(struct ccw_device * cdev,enum dev_event dev_event)651 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
652 {
653 struct subchannel *sch;
654
655 if (cdev->private->state == DEV_STATE_W4SENSE) {
656 cdev->private->flags.doverify = 1;
657 return;
658 }
659 sch = to_subchannel(cdev->dev.parent);
660 /*
661 * Since we might not just be coming from an interrupt from the
662 * subchannel we have to update the schib.
663 */
664 if (cio_update_schib(sch)) {
665 ccw_device_verify_done(cdev, -ENODEV);
666 return;
667 }
668
669 if (scsw_actl(&sch->schib.scsw) != 0 ||
670 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
671 (scsw_stctl(&cdev->private->dma_area->irb.scsw) &
672 SCSW_STCTL_STATUS_PEND)) {
673 /*
674 * No final status yet or final status not yet delivered
675 * to the device driver. Can't do path verification now,
676 * delay until final status was delivered.
677 */
678 cdev->private->flags.doverify = 1;
679 return;
680 }
681 /* Device is idle, we can do the path verification. */
682 cdev->private->state = DEV_STATE_VERIFY;
683 ccw_device_verify_start(cdev);
684 }
685
686 /*
687 * Handle path verification event in boxed state.
688 */
ccw_device_boxed_verify(struct ccw_device * cdev,enum dev_event dev_event)689 static void ccw_device_boxed_verify(struct ccw_device *cdev,
690 enum dev_event dev_event)
691 {
692 struct subchannel *sch = to_subchannel(cdev->dev.parent);
693
694 if (cdev->online) {
695 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)))
696 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
697 else
698 ccw_device_online_verify(cdev, dev_event);
699 } else
700 css_schedule_eval(sch->schid);
701 }
702
703 /*
704 * Pass interrupt to device driver.
705 */
ccw_device_call_handler(struct ccw_device * cdev)706 static int ccw_device_call_handler(struct ccw_device *cdev)
707 {
708 unsigned int stctl;
709 int ending_status;
710
711 /*
712 * we allow for the device action handler if .
713 * - we received ending status
714 * - the action handler requested to see all interrupts
715 * - we received an intermediate status
716 * - fast notification was requested (primary status)
717 * - unsolicited interrupts
718 */
719 stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
720 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
721 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
722 (stctl == SCSW_STCTL_STATUS_PEND);
723 if (!ending_status &&
724 !cdev->private->options.repall &&
725 !(stctl & SCSW_STCTL_INTER_STATUS) &&
726 !(cdev->private->options.fast &&
727 (stctl & SCSW_STCTL_PRIM_STATUS)))
728 return 0;
729
730 if (ending_status)
731 ccw_device_set_timeout(cdev, 0);
732
733 if (cdev->handler)
734 cdev->handler(cdev, cdev->private->intparm,
735 &cdev->private->dma_area->irb);
736
737 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
738 return 1;
739 }
740
741 /*
742 * Got an interrupt for a normal io (state online).
743 */
744 static void
ccw_device_irq(struct ccw_device * cdev,enum dev_event dev_event)745 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
746 {
747 struct irb *irb;
748 int is_cmd;
749
750 irb = this_cpu_ptr(&cio_irb);
751 is_cmd = !scsw_is_tm(&irb->scsw);
752 /* Check for unsolicited interrupt. */
753 if (!scsw_is_solicited(&irb->scsw)) {
754 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
755 !irb->esw.esw0.erw.cons) {
756 /* Unit check but no sense data. Need basic sense. */
757 if (ccw_device_do_sense(cdev, irb) != 0)
758 goto call_handler_unsol;
759 memcpy(&cdev->private->dma_area->irb, irb,
760 sizeof(struct irb));
761 cdev->private->state = DEV_STATE_W4SENSE;
762 cdev->private->intparm = 0;
763 return;
764 }
765 call_handler_unsol:
766 if (cdev->handler)
767 cdev->handler (cdev, 0, irb);
768 if (cdev->private->flags.doverify)
769 ccw_device_online_verify(cdev, 0);
770 return;
771 }
772 /* Accumulate status and find out if a basic sense is needed. */
773 ccw_device_accumulate_irb(cdev, irb);
774 if (is_cmd && cdev->private->flags.dosense) {
775 if (ccw_device_do_sense(cdev, irb) == 0) {
776 cdev->private->state = DEV_STATE_W4SENSE;
777 }
778 return;
779 }
780 /* Call the handler. */
781 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
782 /* Start delayed path verification. */
783 ccw_device_online_verify(cdev, 0);
784 }
785
786 /*
787 * Got an timeout in online state.
788 */
789 static void
ccw_device_online_timeout(struct ccw_device * cdev,enum dev_event dev_event)790 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
791 {
792 int ret;
793
794 ccw_device_set_timeout(cdev, 0);
795 cdev->private->iretry = 255;
796 cdev->private->async_kill_io_rc = -ETIMEDOUT;
797 ret = ccw_device_cancel_halt_clear(cdev);
798 if (ret == -EBUSY) {
799 ccw_device_set_timeout(cdev, 3*HZ);
800 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
801 return;
802 }
803 if (ret)
804 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
805 else if (cdev->handler)
806 cdev->handler(cdev, cdev->private->intparm,
807 ERR_PTR(-ETIMEDOUT));
808 }
809
810 /*
811 * Got an interrupt for a basic sense.
812 */
813 static void
ccw_device_w4sense(struct ccw_device * cdev,enum dev_event dev_event)814 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
815 {
816 struct irb *irb;
817
818 irb = this_cpu_ptr(&cio_irb);
819 /* Check for unsolicited interrupt. */
820 if (scsw_stctl(&irb->scsw) ==
821 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
822 if (scsw_cc(&irb->scsw) == 1)
823 /* Basic sense hasn't started. Try again. */
824 ccw_device_do_sense(cdev, irb);
825 else {
826 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
827 "interrupt during w4sense...\n",
828 cdev->private->dev_id.ssid,
829 cdev->private->dev_id.devno);
830 if (cdev->handler)
831 cdev->handler (cdev, 0, irb);
832 }
833 return;
834 }
835 /*
836 * Check if a halt or clear has been issued in the meanwhile. If yes,
837 * only deliver the halt/clear interrupt to the device driver as if it
838 * had killed the original request.
839 */
840 if (scsw_fctl(&irb->scsw) &
841 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
842 cdev->private->flags.dosense = 0;
843 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
844 ccw_device_accumulate_irb(cdev, irb);
845 goto call_handler;
846 }
847 /* Add basic sense info to irb. */
848 ccw_device_accumulate_basic_sense(cdev, irb);
849 if (cdev->private->flags.dosense) {
850 /* Another basic sense is needed. */
851 ccw_device_do_sense(cdev, irb);
852 return;
853 }
854 call_handler:
855 cdev->private->state = DEV_STATE_ONLINE;
856 /* In case sensing interfered with setting the device online */
857 wake_up(&cdev->private->wait_q);
858 /* Call the handler. */
859 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
860 /* Start delayed path verification. */
861 ccw_device_online_verify(cdev, 0);
862 }
863
864 static void
ccw_device_killing_irq(struct ccw_device * cdev,enum dev_event dev_event)865 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
866 {
867 ccw_device_set_timeout(cdev, 0);
868 /* Start delayed path verification. */
869 ccw_device_online_verify(cdev, 0);
870 /* OK, i/o is dead now. Call interrupt handler. */
871 if (cdev->handler)
872 cdev->handler(cdev, cdev->private->intparm,
873 ERR_PTR(cdev->private->async_kill_io_rc));
874 }
875
876 static void
ccw_device_killing_timeout(struct ccw_device * cdev,enum dev_event dev_event)877 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
878 {
879 int ret;
880
881 ret = ccw_device_cancel_halt_clear(cdev);
882 if (ret == -EBUSY) {
883 ccw_device_set_timeout(cdev, 3*HZ);
884 return;
885 }
886 /* Start delayed path verification. */
887 ccw_device_online_verify(cdev, 0);
888 if (cdev->handler)
889 cdev->handler(cdev, cdev->private->intparm,
890 ERR_PTR(cdev->private->async_kill_io_rc));
891 }
892
ccw_device_kill_io(struct ccw_device * cdev)893 void ccw_device_kill_io(struct ccw_device *cdev)
894 {
895 int ret;
896
897 ccw_device_set_timeout(cdev, 0);
898 cdev->private->iretry = 255;
899 cdev->private->async_kill_io_rc = -EIO;
900 ret = ccw_device_cancel_halt_clear(cdev);
901 if (ret == -EBUSY) {
902 ccw_device_set_timeout(cdev, 3*HZ);
903 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
904 return;
905 }
906 /* Start delayed path verification. */
907 ccw_device_online_verify(cdev, 0);
908 if (cdev->handler)
909 cdev->handler(cdev, cdev->private->intparm,
910 ERR_PTR(-EIO));
911 }
912
913 static void
ccw_device_delay_verify(struct ccw_device * cdev,enum dev_event dev_event)914 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
915 {
916 /* Start verification after current task finished. */
917 cdev->private->flags.doverify = 1;
918 }
919
920 static void
ccw_device_start_id(struct ccw_device * cdev,enum dev_event dev_event)921 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
922 {
923 struct subchannel *sch;
924
925 sch = to_subchannel(cdev->dev.parent);
926 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)) != 0)
927 /* Couldn't enable the subchannel for i/o. Sick device. */
928 return;
929 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
930 ccw_device_sense_id_start(cdev);
931 }
932
ccw_device_trigger_reprobe(struct ccw_device * cdev)933 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
934 {
935 struct subchannel *sch;
936
937 if (cdev->private->state != DEV_STATE_DISCONNECTED)
938 return;
939
940 sch = to_subchannel(cdev->dev.parent);
941 /* Update some values. */
942 if (cio_update_schib(sch))
943 return;
944 /*
945 * The pim, pam, pom values may not be accurate, but they are the best
946 * we have before performing device selection :/
947 */
948 sch->lpm = sch->schib.pmcw.pam & sch->opm;
949 /*
950 * Use the initial configuration since we can't be sure that the old
951 * paths are valid.
952 */
953 io_subchannel_init_config(sch);
954 if (cio_commit_config(sch))
955 return;
956
957 /* We should also udate ssd info, but this has to wait. */
958 /* Check if this is another device which appeared on the same sch. */
959 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
960 css_schedule_eval(sch->schid);
961 else
962 ccw_device_start_id(cdev, 0);
963 }
964
ccw_device_disabled_irq(struct ccw_device * cdev,enum dev_event dev_event)965 static void ccw_device_disabled_irq(struct ccw_device *cdev,
966 enum dev_event dev_event)
967 {
968 struct subchannel *sch;
969
970 sch = to_subchannel(cdev->dev.parent);
971 /*
972 * An interrupt in a disabled state means a previous disable was not
973 * successful - should not happen, but we try to disable again.
974 */
975 cio_disable_subchannel(sch);
976 }
977
978 static void
ccw_device_change_cmfstate(struct ccw_device * cdev,enum dev_event dev_event)979 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
980 {
981 retry_set_schib(cdev);
982 cdev->private->state = DEV_STATE_ONLINE;
983 dev_fsm_event(cdev, dev_event);
984 }
985
ccw_device_update_cmfblock(struct ccw_device * cdev,enum dev_event dev_event)986 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
987 enum dev_event dev_event)
988 {
989 cmf_retry_copy_block(cdev);
990 cdev->private->state = DEV_STATE_ONLINE;
991 dev_fsm_event(cdev, dev_event);
992 }
993
994 static void
ccw_device_quiesce_done(struct ccw_device * cdev,enum dev_event dev_event)995 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
996 {
997 ccw_device_set_timeout(cdev, 0);
998 cdev->private->state = DEV_STATE_NOT_OPER;
999 wake_up(&cdev->private->wait_q);
1000 }
1001
1002 static void
ccw_device_quiesce_timeout(struct ccw_device * cdev,enum dev_event dev_event)1003 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1004 {
1005 int ret;
1006
1007 ret = ccw_device_cancel_halt_clear(cdev);
1008 if (ret == -EBUSY) {
1009 ccw_device_set_timeout(cdev, HZ/10);
1010 } else {
1011 cdev->private->state = DEV_STATE_NOT_OPER;
1012 wake_up(&cdev->private->wait_q);
1013 }
1014 }
1015
1016 /*
1017 * No operation action. This is used e.g. to ignore a timeout event in
1018 * state offline.
1019 */
1020 static void
ccw_device_nop(struct ccw_device * cdev,enum dev_event dev_event)1021 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1022 {
1023 }
1024
1025 /*
1026 * device statemachine
1027 */
1028 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1029 [DEV_STATE_NOT_OPER] = {
1030 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1031 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1032 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1033 [DEV_EVENT_VERIFY] = ccw_device_nop,
1034 },
1035 [DEV_STATE_SENSE_ID] = {
1036 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1037 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1038 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1039 [DEV_EVENT_VERIFY] = ccw_device_nop,
1040 },
1041 [DEV_STATE_OFFLINE] = {
1042 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1043 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1044 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1045 [DEV_EVENT_VERIFY] = ccw_device_offline_verify,
1046 },
1047 [DEV_STATE_VERIFY] = {
1048 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1049 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1050 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1051 [DEV_EVENT_VERIFY] = ccw_device_delay_verify,
1052 },
1053 [DEV_STATE_ONLINE] = {
1054 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1055 [DEV_EVENT_INTERRUPT] = ccw_device_irq,
1056 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
1057 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1058 },
1059 [DEV_STATE_W4SENSE] = {
1060 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1061 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
1062 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1063 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1064 },
1065 [DEV_STATE_DISBAND_PGID] = {
1066 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1067 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1068 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1069 [DEV_EVENT_VERIFY] = ccw_device_nop,
1070 },
1071 [DEV_STATE_BOXED] = {
1072 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1073 [DEV_EVENT_INTERRUPT] = ccw_device_nop,
1074 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1075 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
1076 },
1077 /* states to wait for i/o completion before doing something */
1078 [DEV_STATE_TIMEOUT_KILL] = {
1079 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1080 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
1081 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
1082 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
1083 },
1084 [DEV_STATE_QUIESCE] = {
1085 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
1086 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
1087 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
1088 [DEV_EVENT_VERIFY] = ccw_device_nop,
1089 },
1090 /* special states for devices gone not operational */
1091 [DEV_STATE_DISCONNECTED] = {
1092 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1093 [DEV_EVENT_INTERRUPT] = ccw_device_start_id,
1094 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1095 [DEV_EVENT_VERIFY] = ccw_device_start_id,
1096 },
1097 [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1098 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1099 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1100 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1101 [DEV_EVENT_VERIFY] = ccw_device_nop,
1102 },
1103 [DEV_STATE_CMFCHANGE] = {
1104 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate,
1105 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate,
1106 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate,
1107 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate,
1108 },
1109 [DEV_STATE_CMFUPDATE] = {
1110 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
1111 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
1112 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
1113 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
1114 },
1115 [DEV_STATE_STEAL_LOCK] = {
1116 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1117 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1118 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1119 [DEV_EVENT_VERIFY] = ccw_device_nop,
1120 },
1121 };
1122
1123 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
1124