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