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/export.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/io.h>
14 #include <linux/jiffies.h>
15 #include <linux/string.h>
16
17 #include <asm/ccwdev.h>
18 #include <asm/cio.h>
19 #include <asm/chpid.h>
20
21 #include "cio.h"
22 #include "cio_debug.h"
23 #include "css.h"
24 #include "device.h"
25 #include "chsc.h"
26 #include "ioasm.h"
27 #include "chp.h"
28
29 static int timeout_log_enabled;
30
ccw_timeout_log_setup(char * unused)31 static int __init ccw_timeout_log_setup(char *unused)
32 {
33 timeout_log_enabled = 1;
34 return 1;
35 }
36
37 __setup("ccw_timeout_log", ccw_timeout_log_setup);
38
ccw_timeout_log(struct ccw_device * cdev)39 static void ccw_timeout_log(struct ccw_device *cdev)
40 {
41 struct schib schib;
42 struct subchannel *sch;
43 struct io_subchannel_private *private;
44 union orb *orb;
45 int cc;
46
47 sch = to_subchannel(cdev->dev.parent);
48 private = to_io_private(sch);
49 orb = &private->orb;
50 cc = stsch(sch->schid, &schib);
51
52 printk(KERN_WARNING "cio: ccw device timeout occurred at %lx, "
53 "device information:\n", get_tod_clock());
54 printk(KERN_WARNING "cio: orb:\n");
55 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
56 orb, sizeof(*orb), 0);
57 printk(KERN_WARNING "cio: ccw device bus id: %s\n",
58 dev_name(&cdev->dev));
59 printk(KERN_WARNING "cio: subchannel bus id: %s\n",
60 dev_name(&sch->dev));
61 printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
62 "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
63
64 if (orb->tm.b) {
65 printk(KERN_WARNING "cio: orb indicates transport mode\n");
66 printk(KERN_WARNING "cio: last tcw:\n");
67 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
68 dma32_to_virt(orb->tm.tcw),
69 sizeof(struct tcw), 0);
70 } else {
71 printk(KERN_WARNING "cio: orb indicates command mode\n");
72 if (dma32_to_virt(orb->cmd.cpa) ==
73 &private->dma_area->sense_ccw ||
74 dma32_to_virt(orb->cmd.cpa) ==
75 cdev->private->dma_area->iccws)
76 printk(KERN_WARNING "cio: last channel program "
77 "(intern):\n");
78 else
79 printk(KERN_WARNING "cio: last channel program:\n");
80
81 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
82 dma32_to_virt(orb->cmd.cpa),
83 sizeof(struct ccw1), 0);
84 }
85 printk(KERN_WARNING "cio: ccw device state: %d\n",
86 cdev->private->state);
87 printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
88 printk(KERN_WARNING "cio: schib:\n");
89 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
90 &schib, sizeof(schib), 0);
91 printk(KERN_WARNING "cio: ccw device flags:\n");
92 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1,
93 &cdev->private->flags, sizeof(cdev->private->flags), 0);
94 }
95
96 /*
97 * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
98 */
99 void
ccw_device_timeout(struct timer_list * t)100 ccw_device_timeout(struct timer_list *t)
101 {
102 struct ccw_device_private *priv = timer_container_of(priv, t, timer);
103 struct ccw_device *cdev = priv->cdev;
104
105 spin_lock_irq(cdev->ccwlock);
106 if (timeout_log_enabled)
107 ccw_timeout_log(cdev);
108 dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
109 spin_unlock_irq(cdev->ccwlock);
110 }
111
112 /*
113 * Set timeout
114 */
115 void
ccw_device_set_timeout(struct ccw_device * cdev,int expires)116 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
117 {
118 if (expires == 0)
119 timer_delete(&cdev->private->timer);
120 else
121 mod_timer(&cdev->private->timer, jiffies + expires);
122 }
123
124 int
ccw_device_cancel_halt_clear(struct ccw_device * cdev)125 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
126 {
127 struct subchannel *sch;
128 int ret;
129
130 sch = to_subchannel(cdev->dev.parent);
131 ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
132
133 if (ret == -EIO)
134 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
135 cdev->private->dev_id.ssid,
136 cdev->private->dev_id.devno);
137
138 return ret;
139 }
140
ccw_device_update_sense_data(struct ccw_device * cdev)141 void ccw_device_update_sense_data(struct ccw_device *cdev)
142 {
143 memset(&cdev->id, 0, sizeof(cdev->id));
144 cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type;
145 cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model;
146 cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type;
147 cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model;
148 }
149
ccw_device_test_sense_data(struct ccw_device * cdev)150 int ccw_device_test_sense_data(struct ccw_device *cdev)
151 {
152 return cdev->id.cu_type ==
153 cdev->private->dma_area->senseid.cu_type &&
154 cdev->id.cu_model ==
155 cdev->private->dma_area->senseid.cu_model &&
156 cdev->id.dev_type ==
157 cdev->private->dma_area->senseid.dev_type &&
158 cdev->id.dev_model ==
159 cdev->private->dma_area->senseid.dev_model;
160 }
161
162 /*
163 * The machine won't give us any notification by machine check if a chpid has
164 * been varied online on the SE so we have to find out by magic (i. e. driving
165 * the channel subsystem to device selection and updating our path masks).
166 */
167 static void
__recover_lost_chpids(struct subchannel * sch,int old_lpm)168 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
169 {
170 int mask, i;
171 struct chp_id chpid;
172
173 chp_id_init(&chpid);
174 for (i = 0; i<8; i++) {
175 mask = 0x80 >> i;
176 if (!(sch->lpm & mask))
177 continue;
178 if (old_lpm & mask)
179 continue;
180 chpid.id = sch->schib.pmcw.chpid[i];
181 if (!chp_is_registered(chpid))
182 css_schedule_eval_all();
183 }
184 }
185
186 /*
187 * Stop device recognition.
188 */
189 static void
ccw_device_recog_done(struct ccw_device * cdev,int state)190 ccw_device_recog_done(struct ccw_device *cdev, int state)
191 {
192 struct subchannel *sch;
193 int old_lpm;
194
195 sch = to_subchannel(cdev->dev.parent);
196
197 if (cio_disable_subchannel(sch))
198 state = DEV_STATE_NOT_OPER;
199 /*
200 * Now that we tried recognition, we have performed device selection
201 * through ssch() and the path information is up to date.
202 */
203 old_lpm = sch->lpm;
204
205 /* Check since device may again have become not operational. */
206 if (cio_update_schib(sch))
207 state = DEV_STATE_NOT_OPER;
208 else
209 sch->lpm = sch->schib.pmcw.pam & sch->opm;
210
211 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
212 /* Force reprobe on all chpids. */
213 old_lpm = 0;
214 if (sch->lpm != old_lpm)
215 __recover_lost_chpids(sch, old_lpm);
216 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
217 (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
218 cdev->private->flags.recog_done = 1;
219 cdev->private->state = DEV_STATE_DISCONNECTED;
220 wake_up(&cdev->private->wait_q);
221 return;
222 }
223 switch (state) {
224 case DEV_STATE_NOT_OPER:
225 break;
226 case DEV_STATE_OFFLINE:
227 if (!cdev->online) {
228 ccw_device_update_sense_data(cdev);
229 break;
230 }
231 cdev->private->state = DEV_STATE_OFFLINE;
232 cdev->private->flags.recog_done = 1;
233 if (ccw_device_test_sense_data(cdev)) {
234 cdev->private->flags.donotify = 1;
235 ccw_device_online(cdev);
236 wake_up(&cdev->private->wait_q);
237 } else {
238 ccw_device_update_sense_data(cdev);
239 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
240 }
241 return;
242 case DEV_STATE_BOXED:
243 if (cdev->id.cu_type != 0) { /* device was recognized before */
244 cdev->private->flags.recog_done = 1;
245 cdev->private->state = DEV_STATE_BOXED;
246 wake_up(&cdev->private->wait_q);
247 return;
248 }
249 break;
250 }
251 cdev->private->state = state;
252 io_subchannel_recog_done(cdev);
253 wake_up(&cdev->private->wait_q);
254 }
255
256 /*
257 * Function called from device_id.c after sense id has completed.
258 */
259 void
ccw_device_sense_id_done(struct ccw_device * cdev,int err)260 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
261 {
262 switch (err) {
263 case 0:
264 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
265 break;
266 case -ETIME: /* Sense id stopped by timeout. */
267 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
268 break;
269 default:
270 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
271 break;
272 }
273 }
274
275 /**
276 * ccw_device_notify() - inform the device's driver about an event
277 * @cdev: device for which an event occurred
278 * @event: event that occurred
279 *
280 * Returns:
281 * -%EINVAL if the device is offline or has no driver.
282 * -%EOPNOTSUPP if the device's driver has no notifier registered.
283 * %NOTIFY_OK if the driver wants to keep the device.
284 * %NOTIFY_BAD if the driver doesn't want to keep the device.
285 */
ccw_device_notify(struct ccw_device * cdev,int event)286 int ccw_device_notify(struct ccw_device *cdev, int event)
287 {
288 int ret = -EINVAL;
289
290 if (!cdev->drv)
291 goto out;
292 if (!cdev->online)
293 goto out;
294 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
295 cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
296 event);
297 if (!cdev->drv->notify) {
298 ret = -EOPNOTSUPP;
299 goto out;
300 }
301 if (cdev->drv->notify(cdev, event))
302 ret = NOTIFY_OK;
303 else
304 ret = NOTIFY_BAD;
305 out:
306 return ret;
307 }
308
ccw_device_oper_notify(struct ccw_device * cdev)309 static void ccw_device_oper_notify(struct ccw_device *cdev)
310 {
311 struct subchannel *sch = to_subchannel(cdev->dev.parent);
312
313 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
314 /* Re-enable channel measurements, if needed. */
315 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
316 /* Save indication for new paths. */
317 cdev->private->path_new_mask = sch->vpm;
318 return;
319 }
320 /* Driver doesn't want device back. */
321 ccw_device_set_notoper(cdev);
322 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
323 }
324
325 /*
326 * Finished with online/offline processing.
327 */
328 static void
ccw_device_done(struct ccw_device * cdev,int state)329 ccw_device_done(struct ccw_device *cdev, int state)
330 {
331 struct subchannel *sch;
332
333 sch = to_subchannel(cdev->dev.parent);
334
335 ccw_device_set_timeout(cdev, 0);
336
337 if (state != DEV_STATE_ONLINE)
338 cio_disable_subchannel(sch);
339
340 /* Reset device status. */
341 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
342
343 cdev->private->state = state;
344
345 switch (state) {
346 case DEV_STATE_BOXED:
347 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
348 cdev->private->dev_id.devno, sch->schid.sch_no);
349 if (cdev->online &&
350 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
351 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
352 cdev->private->flags.donotify = 0;
353 break;
354 case DEV_STATE_NOT_OPER:
355 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
356 cdev->private->dev_id.devno, sch->schid.sch_no);
357 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
358 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
359 else
360 ccw_device_set_disconnected(cdev);
361 cdev->private->flags.donotify = 0;
362 break;
363 case DEV_STATE_DISCONNECTED:
364 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
365 "%04x\n", cdev->private->dev_id.devno,
366 sch->schid.sch_no);
367 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
368 cdev->private->state = DEV_STATE_NOT_OPER;
369 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
370 } else
371 ccw_device_set_disconnected(cdev);
372 cdev->private->flags.donotify = 0;
373 break;
374 default:
375 break;
376 }
377
378 if (cdev->private->flags.donotify) {
379 cdev->private->flags.donotify = 0;
380 ccw_device_oper_notify(cdev);
381 }
382 wake_up(&cdev->private->wait_q);
383 }
384
385 /*
386 * Start device recognition.
387 */
ccw_device_recognition(struct ccw_device * cdev)388 void ccw_device_recognition(struct ccw_device *cdev)
389 {
390 struct subchannel *sch = to_subchannel(cdev->dev.parent);
391
392 /*
393 * We used to start here with a sense pgid to find out whether a device
394 * is locked by someone else. Unfortunately, the sense pgid command
395 * code has other meanings on devices predating the path grouping
396 * algorithm, so we start with sense id and box the device after an
397 * timeout (or if sense pgid during path verification detects the device
398 * is locked, as may happen on newer devices).
399 */
400 cdev->private->flags.recog_done = 0;
401 cdev->private->state = DEV_STATE_SENSE_ID;
402 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch))) {
403 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
404 return;
405 }
406 ccw_device_sense_id_start(cdev);
407 }
408
409 /*
410 * Handle events for states that use the ccw request infrastructure.
411 */
ccw_device_request_event(struct ccw_device * cdev,enum dev_event e)412 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
413 {
414 switch (e) {
415 case DEV_EVENT_NOTOPER:
416 ccw_request_notoper(cdev);
417 break;
418 case DEV_EVENT_INTERRUPT:
419 ccw_request_handler(cdev);
420 break;
421 case DEV_EVENT_TIMEOUT:
422 ccw_request_timeout(cdev);
423 break;
424 default:
425 break;
426 }
427 }
428
ccw_device_report_path_events(struct ccw_device * cdev)429 static void ccw_device_report_path_events(struct ccw_device *cdev)
430 {
431 struct subchannel *sch = to_subchannel(cdev->dev.parent);
432 int path_event[8];
433 int chp, mask;
434
435 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
436 path_event[chp] = PE_NONE;
437 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
438 path_event[chp] |= PE_PATH_GONE;
439 if (mask & cdev->private->path_new_mask & sch->vpm)
440 path_event[chp] |= PE_PATH_AVAILABLE;
441 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
442 path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
443 }
444 if (cdev->online && cdev->drv->path_event)
445 cdev->drv->path_event(cdev, path_event);
446 }
447
ccw_device_reset_path_events(struct ccw_device * cdev)448 static void ccw_device_reset_path_events(struct ccw_device *cdev)
449 {
450 cdev->private->path_gone_mask = 0;
451 cdev->private->path_new_mask = 0;
452 cdev->private->pgid_reset_mask = 0;
453 }
454
create_fake_irb(struct irb * irb,int type)455 static void create_fake_irb(struct irb *irb, int type)
456 {
457 memset(irb, 0, sizeof(*irb));
458 if (type == FAKE_CMD_IRB) {
459 struct cmd_scsw *scsw = &irb->scsw.cmd;
460 scsw->cc = 1;
461 scsw->fctl = SCSW_FCTL_START_FUNC;
462 scsw->actl = SCSW_ACTL_START_PEND;
463 scsw->stctl = SCSW_STCTL_STATUS_PEND;
464 } else if (type == FAKE_TM_IRB) {
465 struct tm_scsw *scsw = &irb->scsw.tm;
466 scsw->x = 1;
467 scsw->cc = 1;
468 scsw->fctl = SCSW_FCTL_START_FUNC;
469 scsw->actl = SCSW_ACTL_START_PEND;
470 scsw->stctl = SCSW_STCTL_STATUS_PEND;
471 }
472 }
473
ccw_device_handle_broken_paths(struct ccw_device * cdev)474 static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
475 {
476 struct subchannel *sch = to_subchannel(cdev->dev.parent);
477 u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
478
479 if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
480 ccw_device_schedule_recovery();
481
482 cdev->private->path_broken_mask = broken_paths;
483 }
484
ccw_device_verify_done(struct ccw_device * cdev,int err)485 void ccw_device_verify_done(struct ccw_device *cdev, int err)
486 {
487 struct subchannel *sch;
488
489 sch = to_subchannel(cdev->dev.parent);
490 /* Update schib - pom may have changed. */
491 if (cio_update_schib(sch)) {
492 err = -ENODEV;
493 goto callback;
494 }
495 /* Update lpm with verified path mask. */
496 sch->lpm = sch->vpm;
497 /* Repeat path verification? */
498 if (cdev->private->flags.doverify) {
499 ccw_device_verify_start(cdev);
500 return;
501 }
502 callback:
503 switch (err) {
504 case 0:
505 ccw_device_done(cdev, DEV_STATE_ONLINE);
506 /* Deliver fake irb to device driver, if needed. */
507 if (cdev->private->flags.fake_irb) {
508 CIO_MSG_EVENT(2, "fakeirb: deliver device 0.%x.%04x intparm %lx type=%d\n",
509 cdev->private->dev_id.ssid,
510 cdev->private->dev_id.devno,
511 cdev->private->intparm,
512 cdev->private->flags.fake_irb);
513 create_fake_irb(&cdev->private->dma_area->irb,
514 cdev->private->flags.fake_irb);
515 cdev->private->flags.fake_irb = 0;
516 if (cdev->handler)
517 cdev->handler(cdev, cdev->private->intparm,
518 &cdev->private->dma_area->irb);
519 memset(&cdev->private->dma_area->irb, 0,
520 sizeof(struct irb));
521 }
522 ccw_device_report_path_events(cdev);
523 ccw_device_handle_broken_paths(cdev);
524 break;
525 case -ETIME:
526 case -EUSERS:
527 /* Reset oper notify indication after verify error. */
528 cdev->private->flags.donotify = 0;
529 ccw_device_done(cdev, DEV_STATE_BOXED);
530 break;
531 case -EACCES:
532 /* Reset oper notify indication after verify error. */
533 cdev->private->flags.donotify = 0;
534 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
535 break;
536 default:
537 /* Reset oper notify indication after verify error. */
538 cdev->private->flags.donotify = 0;
539 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
540 break;
541 }
542 ccw_device_reset_path_events(cdev);
543 }
544
545 /*
546 * Get device online.
547 */
548 int
ccw_device_online(struct ccw_device * cdev)549 ccw_device_online(struct ccw_device *cdev)
550 {
551 struct subchannel *sch;
552 int ret;
553
554 if ((cdev->private->state != DEV_STATE_OFFLINE) &&
555 (cdev->private->state != DEV_STATE_BOXED))
556 return -EINVAL;
557 sch = to_subchannel(cdev->dev.parent);
558 ret = cio_enable_subchannel(sch, (u32)virt_to_phys(sch));
559 if (ret != 0) {
560 /* Couldn't enable the subchannel for i/o. Sick device. */
561 if (ret == -ENODEV)
562 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
563 return ret;
564 }
565 /* Start initial path verification. */
566 cdev->private->state = DEV_STATE_VERIFY;
567 ccw_device_verify_start(cdev);
568 return 0;
569 }
570
571 void
ccw_device_disband_done(struct ccw_device * cdev,int err)572 ccw_device_disband_done(struct ccw_device *cdev, int err)
573 {
574 switch (err) {
575 case 0:
576 ccw_device_done(cdev, DEV_STATE_OFFLINE);
577 break;
578 case -ETIME:
579 ccw_device_done(cdev, DEV_STATE_BOXED);
580 break;
581 default:
582 cdev->private->flags.donotify = 0;
583 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
584 break;
585 }
586 }
587
588 /*
589 * Shutdown device.
590 */
591 int
ccw_device_offline(struct ccw_device * cdev)592 ccw_device_offline(struct ccw_device *cdev)
593 {
594 struct subchannel *sch;
595
596 /* Allow ccw_device_offline while disconnected. */
597 if (cdev->private->state == DEV_STATE_DISCONNECTED ||
598 cdev->private->state == DEV_STATE_NOT_OPER) {
599 cdev->private->flags.donotify = 0;
600 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
601 return 0;
602 }
603 if (cdev->private->state == DEV_STATE_BOXED) {
604 ccw_device_done(cdev, DEV_STATE_BOXED);
605 return 0;
606 }
607 if (ccw_device_is_orphan(cdev)) {
608 ccw_device_done(cdev, DEV_STATE_OFFLINE);
609 return 0;
610 }
611 sch = to_subchannel(cdev->dev.parent);
612 if (cio_update_schib(sch))
613 return -ENODEV;
614 if (scsw_actl(&sch->schib.scsw) != 0)
615 return -EBUSY;
616 if (cdev->private->state != DEV_STATE_ONLINE)
617 return -EINVAL;
618 /* Are we doing path grouping? */
619 if (!cdev->private->flags.pgroup) {
620 /* No, set state offline immediately. */
621 ccw_device_done(cdev, DEV_STATE_OFFLINE);
622 return 0;
623 }
624 /* Start Set Path Group commands. */
625 cdev->private->state = DEV_STATE_DISBAND_PGID;
626 ccw_device_disband_start(cdev);
627 return 0;
628 }
629
630 /*
631 * Handle not operational event in non-special state.
632 */
ccw_device_generic_notoper(struct ccw_device * cdev,enum dev_event dev_event)633 static void ccw_device_generic_notoper(struct ccw_device *cdev,
634 enum dev_event dev_event)
635 {
636 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
637 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
638 else
639 ccw_device_set_disconnected(cdev);
640 }
641
642 /*
643 * Handle path verification event in offline state.
644 */
ccw_device_offline_verify(struct ccw_device * cdev,enum dev_event dev_event)645 static void ccw_device_offline_verify(struct ccw_device *cdev,
646 enum dev_event dev_event)
647 {
648 struct subchannel *sch = to_subchannel(cdev->dev.parent);
649
650 css_schedule_eval(sch->schid);
651 }
652
653 /*
654 * Handle path verification event.
655 */
656 static void
ccw_device_online_verify(struct ccw_device * cdev,enum dev_event dev_event)657 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
658 {
659 struct subchannel *sch;
660
661 if (cdev->private->state == DEV_STATE_W4SENSE) {
662 cdev->private->flags.doverify = 1;
663 return;
664 }
665 sch = to_subchannel(cdev->dev.parent);
666 /*
667 * Since we might not just be coming from an interrupt from the
668 * subchannel we have to update the schib.
669 */
670 if (cio_update_schib(sch)) {
671 ccw_device_verify_done(cdev, -ENODEV);
672 return;
673 }
674
675 if (scsw_actl(&sch->schib.scsw) != 0 ||
676 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
677 (scsw_stctl(&cdev->private->dma_area->irb.scsw) &
678 SCSW_STCTL_STATUS_PEND)) {
679 /*
680 * No final status yet or final status not yet delivered
681 * to the device driver. Can't do path verification now,
682 * delay until final status was delivered.
683 */
684 cdev->private->flags.doverify = 1;
685 return;
686 }
687 /* Device is idle, we can do the path verification. */
688 cdev->private->state = DEV_STATE_VERIFY;
689 ccw_device_verify_start(cdev);
690 }
691
692 /*
693 * Handle path verification event in boxed state.
694 */
ccw_device_boxed_verify(struct ccw_device * cdev,enum dev_event dev_event)695 static void ccw_device_boxed_verify(struct ccw_device *cdev,
696 enum dev_event dev_event)
697 {
698 struct subchannel *sch = to_subchannel(cdev->dev.parent);
699
700 if (cdev->online) {
701 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)))
702 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
703 else
704 ccw_device_online_verify(cdev, dev_event);
705 } else
706 css_schedule_eval(sch->schid);
707 }
708
709 /*
710 * Pass interrupt to device driver.
711 */
ccw_device_call_handler(struct ccw_device * cdev)712 static int ccw_device_call_handler(struct ccw_device *cdev)
713 {
714 unsigned int stctl;
715 int ending_status;
716
717 /*
718 * we allow for the device action handler if .
719 * - we received ending status
720 * - the action handler requested to see all interrupts
721 * - we received an intermediate status
722 * - fast notification was requested (primary status)
723 * - unsolicited interrupts
724 */
725 stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
726 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
727 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
728 (stctl == SCSW_STCTL_STATUS_PEND);
729 if (!ending_status &&
730 !cdev->private->options.repall &&
731 !(stctl & SCSW_STCTL_INTER_STATUS) &&
732 !(cdev->private->options.fast &&
733 (stctl & SCSW_STCTL_PRIM_STATUS)))
734 return 0;
735
736 if (ending_status)
737 ccw_device_set_timeout(cdev, 0);
738
739 if (cdev->handler)
740 cdev->handler(cdev, cdev->private->intparm,
741 &cdev->private->dma_area->irb);
742
743 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
744 return 1;
745 }
746
747 /*
748 * Got an interrupt for a normal io (state online).
749 */
750 static void
ccw_device_irq(struct ccw_device * cdev,enum dev_event dev_event)751 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
752 {
753 struct irb *irb;
754 int is_cmd;
755
756 irb = this_cpu_ptr(&cio_irb);
757 is_cmd = !scsw_is_tm(&irb->scsw);
758 /* Check for unsolicited interrupt. */
759 if (!scsw_is_solicited(&irb->scsw)) {
760 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
761 !irb->esw.esw0.erw.cons) {
762 /* Unit check but no sense data. Need basic sense. */
763 if (ccw_device_do_sense(cdev, irb) != 0)
764 goto call_handler_unsol;
765 memcpy(&cdev->private->dma_area->irb, irb,
766 sizeof(struct irb));
767 cdev->private->state = DEV_STATE_W4SENSE;
768 cdev->private->intparm = 0;
769 return;
770 }
771 call_handler_unsol:
772 if (cdev->handler)
773 cdev->handler (cdev, 0, irb);
774 if (cdev->private->flags.doverify)
775 ccw_device_online_verify(cdev, 0);
776 return;
777 }
778 /* Accumulate status and find out if a basic sense is needed. */
779 ccw_device_accumulate_irb(cdev, irb);
780 if (is_cmd && cdev->private->flags.dosense) {
781 if (ccw_device_do_sense(cdev, irb) == 0) {
782 cdev->private->state = DEV_STATE_W4SENSE;
783 }
784 return;
785 }
786 /* Call the handler. */
787 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
788 /* Start delayed path verification. */
789 ccw_device_online_verify(cdev, 0);
790 }
791
792 /*
793 * Got an timeout in online state.
794 */
795 static void
ccw_device_online_timeout(struct ccw_device * cdev,enum dev_event dev_event)796 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
797 {
798 int ret;
799
800 ccw_device_set_timeout(cdev, 0);
801 cdev->private->iretry = 255;
802 cdev->private->async_kill_io_rc = -ETIMEDOUT;
803 ret = ccw_device_cancel_halt_clear(cdev);
804 if (ret == -EBUSY) {
805 ccw_device_set_timeout(cdev, 3*HZ);
806 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
807 return;
808 }
809 if (ret)
810 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
811 else if (cdev->handler)
812 cdev->handler(cdev, cdev->private->intparm,
813 ERR_PTR(-ETIMEDOUT));
814 }
815
816 /*
817 * Got an interrupt for a basic sense.
818 */
819 static void
ccw_device_w4sense(struct ccw_device * cdev,enum dev_event dev_event)820 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
821 {
822 struct irb *irb;
823
824 irb = this_cpu_ptr(&cio_irb);
825 /* Check for unsolicited interrupt. */
826 if (scsw_stctl(&irb->scsw) ==
827 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
828 if (scsw_cc(&irb->scsw) == 1)
829 /* Basic sense hasn't started. Try again. */
830 ccw_device_do_sense(cdev, irb);
831 else {
832 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
833 "interrupt during w4sense...\n",
834 cdev->private->dev_id.ssid,
835 cdev->private->dev_id.devno);
836 if (cdev->handler)
837 cdev->handler (cdev, 0, irb);
838 }
839 return;
840 }
841 /*
842 * Check if a halt or clear has been issued in the meanwhile. If yes,
843 * only deliver the halt/clear interrupt to the device driver as if it
844 * had killed the original request.
845 */
846 if (scsw_fctl(&irb->scsw) &
847 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
848 cdev->private->flags.dosense = 0;
849 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
850 ccw_device_accumulate_irb(cdev, irb);
851 goto call_handler;
852 }
853 /* Add basic sense info to irb. */
854 ccw_device_accumulate_basic_sense(cdev, irb);
855 if (cdev->private->flags.dosense) {
856 /* Another basic sense is needed. */
857 ccw_device_do_sense(cdev, irb);
858 return;
859 }
860 call_handler:
861 cdev->private->state = DEV_STATE_ONLINE;
862 /* In case sensing interfered with setting the device online */
863 wake_up(&cdev->private->wait_q);
864 /* Call the handler. */
865 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
866 /* Start delayed path verification. */
867 ccw_device_online_verify(cdev, 0);
868 }
869
870 static void
ccw_device_killing_irq(struct ccw_device * cdev,enum dev_event dev_event)871 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
872 {
873 ccw_device_set_timeout(cdev, 0);
874 /* Start delayed path verification. */
875 ccw_device_online_verify(cdev, 0);
876 /* OK, i/o is dead now. Call interrupt handler. */
877 if (cdev->handler)
878 cdev->handler(cdev, cdev->private->intparm,
879 ERR_PTR(cdev->private->async_kill_io_rc));
880 }
881
882 static void
ccw_device_killing_timeout(struct ccw_device * cdev,enum dev_event dev_event)883 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
884 {
885 int ret;
886
887 ret = ccw_device_cancel_halt_clear(cdev);
888 if (ret == -EBUSY) {
889 ccw_device_set_timeout(cdev, 3*HZ);
890 return;
891 }
892 /* Start delayed path verification. */
893 ccw_device_online_verify(cdev, 0);
894 if (cdev->handler)
895 cdev->handler(cdev, cdev->private->intparm,
896 ERR_PTR(cdev->private->async_kill_io_rc));
897 }
898
ccw_device_kill_io(struct ccw_device * cdev)899 void ccw_device_kill_io(struct ccw_device *cdev)
900 {
901 int ret;
902
903 ccw_device_set_timeout(cdev, 0);
904 cdev->private->iretry = 255;
905 cdev->private->async_kill_io_rc = -EIO;
906 ret = ccw_device_cancel_halt_clear(cdev);
907 if (ret == -EBUSY) {
908 ccw_device_set_timeout(cdev, 3*HZ);
909 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
910 return;
911 }
912 /* Start delayed path verification. */
913 ccw_device_online_verify(cdev, 0);
914 if (cdev->handler)
915 cdev->handler(cdev, cdev->private->intparm,
916 ERR_PTR(-EIO));
917 }
918
919 static void
ccw_device_delay_verify(struct ccw_device * cdev,enum dev_event dev_event)920 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
921 {
922 /* Start verification after current task finished. */
923 cdev->private->flags.doverify = 1;
924 }
925
926 static void
ccw_device_start_id(struct ccw_device * cdev,enum dev_event dev_event)927 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
928 {
929 struct subchannel *sch;
930
931 sch = to_subchannel(cdev->dev.parent);
932 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)) != 0)
933 /* Couldn't enable the subchannel for i/o. Sick device. */
934 return;
935 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
936 ccw_device_sense_id_start(cdev);
937 }
938
ccw_device_trigger_reprobe(struct ccw_device * cdev)939 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
940 {
941 struct subchannel *sch;
942
943 if (cdev->private->state != DEV_STATE_DISCONNECTED)
944 return;
945
946 sch = to_subchannel(cdev->dev.parent);
947 /* Update some values. */
948 if (cio_update_schib(sch))
949 return;
950 /*
951 * The pim, pam, pom values may not be accurate, but they are the best
952 * we have before performing device selection :/
953 */
954 sch->lpm = sch->schib.pmcw.pam & sch->opm;
955 /*
956 * Use the initial configuration since we can't be sure that the old
957 * paths are valid.
958 */
959 io_subchannel_init_config(sch);
960 if (cio_commit_config(sch))
961 return;
962
963 /* We should also udate ssd info, but this has to wait. */
964 /* Check if this is another device which appeared on the same sch. */
965 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
966 css_schedule_eval(sch->schid);
967 else
968 ccw_device_start_id(cdev, 0);
969 }
970
ccw_device_disabled_irq(struct ccw_device * cdev,enum dev_event dev_event)971 static void ccw_device_disabled_irq(struct ccw_device *cdev,
972 enum dev_event dev_event)
973 {
974 struct subchannel *sch;
975
976 sch = to_subchannel(cdev->dev.parent);
977 /*
978 * An interrupt in a disabled state means a previous disable was not
979 * successful - should not happen, but we try to disable again.
980 */
981 cio_disable_subchannel(sch);
982 }
983
984 static void
ccw_device_change_cmfstate(struct ccw_device * cdev,enum dev_event dev_event)985 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
986 {
987 retry_set_schib(cdev);
988 cdev->private->state = DEV_STATE_ONLINE;
989 dev_fsm_event(cdev, dev_event);
990 }
991
ccw_device_update_cmfblock(struct ccw_device * cdev,enum dev_event dev_event)992 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
993 enum dev_event dev_event)
994 {
995 cmf_retry_copy_block(cdev);
996 cdev->private->state = DEV_STATE_ONLINE;
997 dev_fsm_event(cdev, dev_event);
998 }
999
1000 static void
ccw_device_quiesce_done(struct ccw_device * cdev,enum dev_event dev_event)1001 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1002 {
1003 ccw_device_set_timeout(cdev, 0);
1004 cdev->private->state = DEV_STATE_NOT_OPER;
1005 wake_up(&cdev->private->wait_q);
1006 }
1007
1008 static void
ccw_device_quiesce_timeout(struct ccw_device * cdev,enum dev_event dev_event)1009 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1010 {
1011 int ret;
1012
1013 ret = ccw_device_cancel_halt_clear(cdev);
1014 if (ret == -EBUSY) {
1015 ccw_device_set_timeout(cdev, HZ/10);
1016 } else {
1017 cdev->private->state = DEV_STATE_NOT_OPER;
1018 wake_up(&cdev->private->wait_q);
1019 }
1020 }
1021
1022 /*
1023 * No operation action. This is used e.g. to ignore a timeout event in
1024 * state offline.
1025 */
1026 static void
ccw_device_nop(struct ccw_device * cdev,enum dev_event dev_event)1027 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1028 {
1029 }
1030
1031 /*
1032 * device statemachine
1033 */
1034 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1035 [DEV_STATE_NOT_OPER] = {
1036 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1037 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1038 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1039 [DEV_EVENT_VERIFY] = ccw_device_nop,
1040 },
1041 [DEV_STATE_SENSE_ID] = {
1042 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1043 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1044 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1045 [DEV_EVENT_VERIFY] = ccw_device_nop,
1046 },
1047 [DEV_STATE_OFFLINE] = {
1048 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1049 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq,
1050 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1051 [DEV_EVENT_VERIFY] = ccw_device_offline_verify,
1052 },
1053 [DEV_STATE_VERIFY] = {
1054 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1055 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1056 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1057 [DEV_EVENT_VERIFY] = ccw_device_delay_verify,
1058 },
1059 [DEV_STATE_ONLINE] = {
1060 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1061 [DEV_EVENT_INTERRUPT] = ccw_device_irq,
1062 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout,
1063 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1064 },
1065 [DEV_STATE_W4SENSE] = {
1066 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1067 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense,
1068 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1069 [DEV_EVENT_VERIFY] = ccw_device_online_verify,
1070 },
1071 [DEV_STATE_DISBAND_PGID] = {
1072 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1073 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1074 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1075 [DEV_EVENT_VERIFY] = ccw_device_nop,
1076 },
1077 [DEV_STATE_BOXED] = {
1078 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1079 [DEV_EVENT_INTERRUPT] = ccw_device_nop,
1080 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1081 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify,
1082 },
1083 /* states to wait for i/o completion before doing something */
1084 [DEV_STATE_TIMEOUT_KILL] = {
1085 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper,
1086 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq,
1087 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout,
1088 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME
1089 },
1090 [DEV_STATE_QUIESCE] = {
1091 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done,
1092 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done,
1093 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout,
1094 [DEV_EVENT_VERIFY] = ccw_device_nop,
1095 },
1096 /* special states for devices gone not operational */
1097 [DEV_STATE_DISCONNECTED] = {
1098 [DEV_EVENT_NOTOPER] = ccw_device_nop,
1099 [DEV_EVENT_INTERRUPT] = ccw_device_start_id,
1100 [DEV_EVENT_TIMEOUT] = ccw_device_nop,
1101 [DEV_EVENT_VERIFY] = ccw_device_start_id,
1102 },
1103 [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1104 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1105 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1106 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1107 [DEV_EVENT_VERIFY] = ccw_device_nop,
1108 },
1109 [DEV_STATE_CMFCHANGE] = {
1110 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate,
1111 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate,
1112 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate,
1113 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate,
1114 },
1115 [DEV_STATE_CMFUPDATE] = {
1116 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock,
1117 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock,
1118 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock,
1119 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock,
1120 },
1121 [DEV_STATE_STEAL_LOCK] = {
1122 [DEV_EVENT_NOTOPER] = ccw_device_request_event,
1123 [DEV_EVENT_INTERRUPT] = ccw_device_request_event,
1124 [DEV_EVENT_TIMEOUT] = ccw_device_request_event,
1125 [DEV_EVENT_VERIFY] = ccw_device_nop,
1126 },
1127 };
1128
1129 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);
1130