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1/*
2 * drivers/s390/cio/chp.c
3 *
4 * Copyright IBM Corp. 1999,2010
5 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
6 * Arnd Bergmann (arndb@de.ibm.com)
7 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
8 */
9
10#include <linux/bug.h>
11#include <linux/workqueue.h>
12#include <linux/spinlock.h>
13#include <linux/init.h>
14#include <linux/jiffies.h>
15#include <linux/wait.h>
16#include <linux/mutex.h>
17#include <linux/errno.h>
18#include <linux/slab.h>
19#include <asm/chpid.h>
20#include <asm/sclp.h>
21#include <asm/crw.h>
22
23#include "cio.h"
24#include "css.h"
25#include "ioasm.h"
26#include "cio_debug.h"
27#include "chp.h"
28
29#define to_channelpath(device) container_of(device, struct channel_path, dev)
30#define CHP_INFO_UPDATE_INTERVAL 1*HZ
31
32enum cfg_task_t {
33 cfg_none,
34 cfg_configure,
35 cfg_deconfigure
36};
37
38/* Map for pending configure tasks. */
39static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1];
40static DEFINE_MUTEX(cfg_lock);
41static int cfg_busy;
42
43/* Map for channel-path status. */
44static struct sclp_chp_info chp_info;
45static DEFINE_MUTEX(info_lock);
46
47/* Time after which channel-path status may be outdated. */
48static unsigned long chp_info_expires;
49
50/* Workqueue to perform pending configure tasks. */
51static struct workqueue_struct *chp_wq;
52static struct work_struct cfg_work;
53
54/* Wait queue for configure completion events. */
55static wait_queue_head_t cfg_wait_queue;
56
57/* Set vary state for given chpid. */
58static void set_chp_logically_online(struct chp_id chpid, int onoff)
59{
60 chpid_to_chp(chpid)->state = onoff;
61}
62
63/* On success return 0 if channel-path is varied offline, 1 if it is varied
64 * online. Return -ENODEV if channel-path is not registered. */
65int chp_get_status(struct chp_id chpid)
66{
67 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
68}
69
70/**
71 * chp_get_sch_opm - return opm for subchannel
72 * @sch: subchannel
73 *
74 * Calculate and return the operational path mask (opm) based on the chpids
75 * used by the subchannel and the status of the associated channel-paths.
76 */
77u8 chp_get_sch_opm(struct subchannel *sch)
78{
79 struct chp_id chpid;
80 int opm;
81 int i;
82
83 opm = 0;
84 chp_id_init(&chpid);
85 for (i = 0; i < 8; i++) {
86 opm <<= 1;
87 chpid.id = sch->schib.pmcw.chpid[i];
88 if (chp_get_status(chpid) != 0)
89 opm |= 1;
90 }
91 return opm;
92}
93EXPORT_SYMBOL_GPL(chp_get_sch_opm);
94
95/**
96 * chp_is_registered - check if a channel-path is registered
97 * @chpid: channel-path ID
98 *
99 * Return non-zero if a channel-path with the given chpid is registered,
100 * zero otherwise.
101 */
102int chp_is_registered(struct chp_id chpid)
103{
104 return chpid_to_chp(chpid) != NULL;
105}
106
107/*
108 * Function: s390_vary_chpid
109 * Varies the specified chpid online or offline
110 */
111static int s390_vary_chpid(struct chp_id chpid, int on)
112{
113 char dbf_text[15];
114 int status;
115
116 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
117 chpid.id);
118 CIO_TRACE_EVENT(2, dbf_text);
119
120 status = chp_get_status(chpid);
121 if (!on && !status)
122 return 0;
123
124 set_chp_logically_online(chpid, on);
125 chsc_chp_vary(chpid, on);
126 return 0;
127}
128
129/*
130 * Channel measurement related functions
131 */
132static ssize_t chp_measurement_chars_read(struct file *filp,
133 struct kobject *kobj,
134 struct bin_attribute *bin_attr,
135 char *buf, loff_t off, size_t count)
136{
137 struct channel_path *chp;
138 struct device *device;
139
140 device = container_of(kobj, struct device, kobj);
141 chp = to_channelpath(device);
142 if (!chp->cmg_chars)
143 return 0;
144
145 return memory_read_from_buffer(buf, count, &off,
146 chp->cmg_chars, sizeof(struct cmg_chars));
147}
148
149static struct bin_attribute chp_measurement_chars_attr = {
150 .attr = {
151 .name = "measurement_chars",
152 .mode = S_IRUSR,
153 },
154 .size = sizeof(struct cmg_chars),
155 .read = chp_measurement_chars_read,
156};
157
158static void chp_measurement_copy_block(struct cmg_entry *buf,
159 struct channel_subsystem *css,
160 struct chp_id chpid)
161{
162 void *area;
163 struct cmg_entry *entry, reference_buf;
164 int idx;
165
166 if (chpid.id < 128) {
167 area = css->cub_addr1;
168 idx = chpid.id;
169 } else {
170 area = css->cub_addr2;
171 idx = chpid.id - 128;
172 }
173 entry = area + (idx * sizeof(struct cmg_entry));
174 do {
175 memcpy(buf, entry, sizeof(*entry));
176 memcpy(&reference_buf, entry, sizeof(*entry));
177 } while (reference_buf.values[0] != buf->values[0]);
178}
179
180static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj,
181 struct bin_attribute *bin_attr,
182 char *buf, loff_t off, size_t count)
183{
184 struct channel_path *chp;
185 struct channel_subsystem *css;
186 struct device *device;
187 unsigned int size;
188
189 device = container_of(kobj, struct device, kobj);
190 chp = to_channelpath(device);
191 css = to_css(chp->dev.parent);
192
193 size = sizeof(struct cmg_entry);
194
195 /* Only allow single reads. */
196 if (off || count < size)
197 return 0;
198 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
199 count = size;
200 return count;
201}
202
203static struct bin_attribute chp_measurement_attr = {
204 .attr = {
205 .name = "measurement",
206 .mode = S_IRUSR,
207 },
208 .size = sizeof(struct cmg_entry),
209 .read = chp_measurement_read,
210};
211
212void chp_remove_cmg_attr(struct channel_path *chp)
213{
214 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
215 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
216}
217
218int chp_add_cmg_attr(struct channel_path *chp)
219{
220 int ret;
221
222 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
223 if (ret)
224 return ret;
225 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
226 if (ret)
227 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
228 return ret;
229}
230
231/*
232 * Files for the channel path entries.
233 */
234static ssize_t chp_status_show(struct device *dev,
235 struct device_attribute *attr, char *buf)
236{
237 struct channel_path *chp = to_channelpath(dev);
238 int status;
239
240 mutex_lock(&chp->lock);
241 status = chp->state;
242 mutex_unlock(&chp->lock);
243
244 return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n");
245}
246
247static ssize_t chp_status_write(struct device *dev,
248 struct device_attribute *attr,
249 const char *buf, size_t count)
250{
251 struct channel_path *cp = to_channelpath(dev);
252 char cmd[10];
253 int num_args;
254 int error;
255
256 num_args = sscanf(buf, "%5s", cmd);
257 if (!num_args)
258 return count;
259
260 if (!strnicmp(cmd, "on", 2) || !strcmp(cmd, "1")) {
261 mutex_lock(&cp->lock);
262 error = s390_vary_chpid(cp->chpid, 1);
263 mutex_unlock(&cp->lock);
264 } else if (!strnicmp(cmd, "off", 3) || !strcmp(cmd, "0")) {
265 mutex_lock(&cp->lock);
266 error = s390_vary_chpid(cp->chpid, 0);
267 mutex_unlock(&cp->lock);
268 } else
269 error = -EINVAL;
270
271 return error < 0 ? error : count;
272}
273
274static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
275
276static ssize_t chp_configure_show(struct device *dev,
277 struct device_attribute *attr, char *buf)
278{
279 struct channel_path *cp;
280 int status;
281
282 cp = to_channelpath(dev);
283 status = chp_info_get_status(cp->chpid);
284 if (status < 0)
285 return status;
286
287 return snprintf(buf, PAGE_SIZE, "%d\n", status);
288}
289
290static int cfg_wait_idle(void);
291
292static ssize_t chp_configure_write(struct device *dev,
293 struct device_attribute *attr,
294 const char *buf, size_t count)
295{
296 struct channel_path *cp;
297 int val;
298 char delim;
299
300 if (sscanf(buf, "%d %c", &val, &delim) != 1)
301 return -EINVAL;
302 if (val != 0 && val != 1)
303 return -EINVAL;
304 cp = to_channelpath(dev);
305 chp_cfg_schedule(cp->chpid, val);
306 cfg_wait_idle();
307
308 return count;
309}
310
311static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
312
313static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
314 char *buf)
315{
316 struct channel_path *chp = to_channelpath(dev);
317 u8 type;
318
319 mutex_lock(&chp->lock);
320 type = chp->desc.desc;
321 mutex_unlock(&chp->lock);
322 return sprintf(buf, "%x\n", type);
323}
324
325static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
326
327static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
328 char *buf)
329{
330 struct channel_path *chp = to_channelpath(dev);
331
332 if (!chp)
333 return 0;
334 if (chp->cmg == -1) /* channel measurements not available */
335 return sprintf(buf, "unknown\n");
336 return sprintf(buf, "%x\n", chp->cmg);
337}
338
339static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
340
341static ssize_t chp_shared_show(struct device *dev,
342 struct device_attribute *attr, char *buf)
343{
344 struct channel_path *chp = to_channelpath(dev);
345
346 if (!chp)
347 return 0;
348 if (chp->shared == -1) /* channel measurements not available */
349 return sprintf(buf, "unknown\n");
350 return sprintf(buf, "%x\n", chp->shared);
351}
352
353static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
354
355static struct attribute *chp_attrs[] = {
356 &dev_attr_status.attr,
357 &dev_attr_configure.attr,
358 &dev_attr_type.attr,
359 &dev_attr_cmg.attr,
360 &dev_attr_shared.attr,
361 NULL,
362};
363
364static struct attribute_group chp_attr_group = {
365 .attrs = chp_attrs,
366};
367
368static void chp_release(struct device *dev)
369{
370 struct channel_path *cp;
371
372 cp = to_channelpath(dev);
373 kfree(cp);
374}
375
376/**
377 * chp_new - register a new channel-path
378 * @chpid - channel-path ID
379 *
380 * Create and register data structure representing new channel-path. Return
381 * zero on success, non-zero otherwise.
382 */
383int chp_new(struct chp_id chpid)
384{
385 struct channel_path *chp;
386 int ret;
387
388 if (chp_is_registered(chpid))
389 return 0;
390 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
391 if (!chp)
392 return -ENOMEM;
393
394 /* fill in status, etc. */
395 chp->chpid = chpid;
396 chp->state = 1;
397 chp->dev.parent = &channel_subsystems[chpid.cssid]->device;
398 chp->dev.release = chp_release;
399 mutex_init(&chp->lock);
400
401 /* Obtain channel path description and fill it in. */
402 ret = chsc_determine_base_channel_path_desc(chpid, &chp->desc);
403 if (ret)
404 goto out_free;
405 if ((chp->desc.flags & 0x80) == 0) {
406 ret = -ENODEV;
407 goto out_free;
408 }
409 /* Get channel-measurement characteristics. */
410 if (css_chsc_characteristics.scmc && css_chsc_characteristics.secm) {
411 ret = chsc_get_channel_measurement_chars(chp);
412 if (ret)
413 goto out_free;
414 } else {
415 chp->cmg = -1;
416 }
417 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id);
418
419 /* make it known to the system */
420 ret = device_register(&chp->dev);
421 if (ret) {
422 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
423 chpid.cssid, chpid.id, ret);
424 put_device(&chp->dev);
425 goto out;
426 }
427 ret = sysfs_create_group(&chp->dev.kobj, &chp_attr_group);
428 if (ret) {
429 device_unregister(&chp->dev);
430 goto out;
431 }
432 mutex_lock(&channel_subsystems[chpid.cssid]->mutex);
433 if (channel_subsystems[chpid.cssid]->cm_enabled) {
434 ret = chp_add_cmg_attr(chp);
435 if (ret) {
436 sysfs_remove_group(&chp->dev.kobj, &chp_attr_group);
437 device_unregister(&chp->dev);
438 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex);
439 goto out;
440 }
441 }
442 channel_subsystems[chpid.cssid]->chps[chpid.id] = chp;
443 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex);
444 goto out;
445out_free:
446 kfree(chp);
447out:
448 return ret;
449}
450
451/**
452 * chp_get_chp_desc - return newly allocated channel-path description
453 * @chpid: channel-path ID
454 *
455 * On success return a newly allocated copy of the channel-path description
456 * data associated with the given channel-path ID. Return %NULL on error.
457 */
458void *chp_get_chp_desc(struct chp_id chpid)
459{
460 struct channel_path *chp;
461 struct channel_path_desc *desc;
462
463 chp = chpid_to_chp(chpid);
464 if (!chp)
465 return NULL;
466 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL);
467 if (!desc)
468 return NULL;
469
470 mutex_lock(&chp->lock);
471 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc));
472 mutex_unlock(&chp->lock);
473 return desc;
474}
475
476/**
477 * chp_process_crw - process channel-path status change
478 * @crw0: channel report-word to handler
479 * @crw1: second channel-report word (always NULL)
480 * @overflow: crw overflow indication
481 *
482 * Handle channel-report-words indicating that the status of a channel-path
483 * has changed.
484 */
485static void chp_process_crw(struct crw *crw0, struct crw *crw1,
486 int overflow)
487{
488 struct chp_id chpid;
489
490 if (overflow) {
491 css_schedule_eval_all();
492 return;
493 }
494 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
495 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
496 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
497 crw0->erc, crw0->rsid);
498 /*
499 * Check for solicited machine checks. These are
500 * created by reset channel path and need not be
501 * handled here.
502 */
503 if (crw0->slct) {
504 CIO_CRW_EVENT(2, "solicited machine check for "
505 "channel path %02X\n", crw0->rsid);
506 return;
507 }
508 chp_id_init(&chpid);
509 chpid.id = crw0->rsid;
510 switch (crw0->erc) {
511 case CRW_ERC_IPARM: /* Path has come. */
512 if (!chp_is_registered(chpid))
513 chp_new(chpid);
514 chsc_chp_online(chpid);
515 break;
516 case CRW_ERC_PERRI: /* Path has gone. */
517 case CRW_ERC_PERRN:
518 chsc_chp_offline(chpid);
519 break;
520 default:
521 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
522 crw0->erc);
523 }
524}
525
526int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link)
527{
528 int i;
529 int mask;
530
531 for (i = 0; i < 8; i++) {
532 mask = 0x80 >> i;
533 if (!(ssd->path_mask & mask))
534 continue;
535 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid))
536 continue;
537 if ((ssd->fla_valid_mask & mask) &&
538 ((ssd->fla[i] & link->fla_mask) != link->fla))
539 continue;
540 return mask;
541 }
542 return 0;
543}
544EXPORT_SYMBOL_GPL(chp_ssd_get_mask);
545
546static inline int info_bit_num(struct chp_id id)
547{
548 return id.id + id.cssid * (__MAX_CHPID + 1);
549}
550
551/* Force chp_info refresh on next call to info_validate(). */
552static void info_expire(void)
553{
554 mutex_lock(&info_lock);
555 chp_info_expires = jiffies - 1;
556 mutex_unlock(&info_lock);
557}
558
559/* Ensure that chp_info is up-to-date. */
560static int info_update(void)
561{
562 int rc;
563
564 mutex_lock(&info_lock);
565 rc = 0;
566 if (time_after(jiffies, chp_info_expires)) {
567 /* Data is too old, update. */
568 rc = sclp_chp_read_info(&chp_info);
569 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
570 }
571 mutex_unlock(&info_lock);
572
573 return rc;
574}
575
576/**
577 * chp_info_get_status - retrieve configure status of a channel-path
578 * @chpid: channel-path ID
579 *
580 * On success, return 0 for standby, 1 for configured, 2 for reserved,
581 * 3 for not recognized. Return negative error code on error.
582 */
583int chp_info_get_status(struct chp_id chpid)
584{
585 int rc;
586 int bit;
587
588 rc = info_update();
589 if (rc)
590 return rc;
591
592 bit = info_bit_num(chpid);
593 mutex_lock(&info_lock);
594 if (!chp_test_bit(chp_info.recognized, bit))
595 rc = CHP_STATUS_NOT_RECOGNIZED;
596 else if (chp_test_bit(chp_info.configured, bit))
597 rc = CHP_STATUS_CONFIGURED;
598 else if (chp_test_bit(chp_info.standby, bit))
599 rc = CHP_STATUS_STANDBY;
600 else
601 rc = CHP_STATUS_RESERVED;
602 mutex_unlock(&info_lock);
603
604 return rc;
605}
606
607/* Return configure task for chpid. */
608static enum cfg_task_t cfg_get_task(struct chp_id chpid)
609{
610 return chp_cfg_task[chpid.cssid][chpid.id];
611}
612
613/* Set configure task for chpid. */
614static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
615{
616 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
617}
618
619/* Perform one configure/deconfigure request. Reschedule work function until
620 * last request. */
621static void cfg_func(struct work_struct *work)
622{
623 struct chp_id chpid;
624 enum cfg_task_t t;
625 int rc;
626
627 mutex_lock(&cfg_lock);
628 t = cfg_none;
629 chp_id_for_each(&chpid) {
630 t = cfg_get_task(chpid);
631 if (t != cfg_none) {
632 cfg_set_task(chpid, cfg_none);
633 break;
634 }
635 }
636 mutex_unlock(&cfg_lock);
637
638 switch (t) {
639 case cfg_configure:
640 rc = sclp_chp_configure(chpid);
641 if (rc)
642 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
643 "%d\n", chpid.cssid, chpid.id, rc);
644 else {
645 info_expire();
646 chsc_chp_online(chpid);
647 }
648 break;
649 case cfg_deconfigure:
650 rc = sclp_chp_deconfigure(chpid);
651 if (rc)
652 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
653 "%d\n", chpid.cssid, chpid.id, rc);
654 else {
655 info_expire();
656 chsc_chp_offline(chpid);
657 }
658 break;
659 case cfg_none:
660 /* Get updated information after last change. */
661 info_update();
662 mutex_lock(&cfg_lock);
663 cfg_busy = 0;
664 mutex_unlock(&cfg_lock);
665 wake_up_interruptible(&cfg_wait_queue);
666 return;
667 }
668 queue_work(chp_wq, &cfg_work);
669}
670
671/**
672 * chp_cfg_schedule - schedule chpid configuration request
673 * @chpid - channel-path ID
674 * @configure - Non-zero for configure, zero for deconfigure
675 *
676 * Schedule a channel-path configuration/deconfiguration request.
677 */
678void chp_cfg_schedule(struct chp_id chpid, int configure)
679{
680 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
681 configure);
682 mutex_lock(&cfg_lock);
683 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
684 cfg_busy = 1;
685 mutex_unlock(&cfg_lock);
686 queue_work(chp_wq, &cfg_work);
687}
688
689/**
690 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
691 * @chpid - channel-path ID
692 *
693 * Cancel an active channel-path deconfiguration request if it has not yet
694 * been performed.
695 */
696void chp_cfg_cancel_deconfigure(struct chp_id chpid)
697{
698 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
699 mutex_lock(&cfg_lock);
700 if (cfg_get_task(chpid) == cfg_deconfigure)
701 cfg_set_task(chpid, cfg_none);
702 mutex_unlock(&cfg_lock);
703}
704
705static int cfg_wait_idle(void)
706{
707 if (wait_event_interruptible(cfg_wait_queue, !cfg_busy))
708 return -ERESTARTSYS;
709 return 0;
710}
711
712static int __init chp_init(void)
713{
714 struct chp_id chpid;
715 int ret;
716
717 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw);
718 if (ret)
719 return ret;
720 chp_wq = create_singlethread_workqueue("cio_chp");
721 if (!chp_wq) {
722 crw_unregister_handler(CRW_RSC_CPATH);
723 return -ENOMEM;
724 }
725 INIT_WORK(&cfg_work, cfg_func);
726 init_waitqueue_head(&cfg_wait_queue);
727 if (info_update())
728 return 0;
729 /* Register available channel-paths. */
730 chp_id_for_each(&chpid) {
731 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED)
732 chp_new(chpid);
733 }
734
735 return 0;
736}
737
738subsys_initcall(chp_init);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 1999, 2010
4 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
5 * Arnd Bergmann (arndb@de.ibm.com)
6 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
7 */
8
9#include <linux/bug.h>
10#include <linux/workqueue.h>
11#include <linux/spinlock.h>
12#include <linux/export.h>
13#include <linux/sched.h>
14#include <linux/init.h>
15#include <linux/jiffies.h>
16#include <linux/wait.h>
17#include <linux/mutex.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20#include <asm/chpid.h>
21#include <asm/sclp.h>
22#include <asm/crw.h>
23
24#include "cio.h"
25#include "css.h"
26#include "ioasm.h"
27#include "cio_debug.h"
28#include "chp.h"
29
30#define to_channelpath(device) container_of(device, struct channel_path, dev)
31#define CHP_INFO_UPDATE_INTERVAL 1*HZ
32
33enum cfg_task_t {
34 cfg_none,
35 cfg_configure,
36 cfg_deconfigure
37};
38
39/* Map for pending configure tasks. */
40static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1];
41static DEFINE_SPINLOCK(cfg_lock);
42
43/* Map for channel-path status. */
44static struct sclp_chp_info chp_info;
45static DEFINE_MUTEX(info_lock);
46
47/* Time after which channel-path status may be outdated. */
48static unsigned long chp_info_expires;
49
50static struct work_struct cfg_work;
51
52/* Wait queue for configure completion events. */
53static DECLARE_WAIT_QUEUE_HEAD(cfg_wait_queue);
54
55/* Set vary state for given chpid. */
56static void set_chp_logically_online(struct chp_id chpid, int onoff)
57{
58 chpid_to_chp(chpid)->state = onoff;
59}
60
61/* On success return 0 if channel-path is varied offline, 1 if it is varied
62 * online. Return -ENODEV if channel-path is not registered. */
63int chp_get_status(struct chp_id chpid)
64{
65 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
66}
67
68/**
69 * chp_get_sch_opm - return opm for subchannel
70 * @sch: subchannel
71 *
72 * Calculate and return the operational path mask (opm) based on the chpids
73 * used by the subchannel and the status of the associated channel-paths.
74 */
75u8 chp_get_sch_opm(struct subchannel *sch)
76{
77 struct chp_id chpid;
78 int opm;
79 int i;
80
81 opm = 0;
82 chp_id_init(&chpid);
83 for (i = 0; i < 8; i++) {
84 opm <<= 1;
85 chpid.id = sch->schib.pmcw.chpid[i];
86 if (chp_get_status(chpid) != 0)
87 opm |= 1;
88 }
89 return opm;
90}
91EXPORT_SYMBOL_GPL(chp_get_sch_opm);
92
93/**
94 * chp_is_registered - check if a channel-path is registered
95 * @chpid: channel-path ID
96 *
97 * Return non-zero if a channel-path with the given chpid is registered,
98 * zero otherwise.
99 */
100int chp_is_registered(struct chp_id chpid)
101{
102 return chpid_to_chp(chpid) != NULL;
103}
104
105/*
106 * Function: s390_vary_chpid
107 * Varies the specified chpid online or offline
108 */
109static int s390_vary_chpid(struct chp_id chpid, int on)
110{
111 char dbf_text[15];
112 int status;
113
114 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
115 chpid.id);
116 CIO_TRACE_EVENT(2, dbf_text);
117
118 status = chp_get_status(chpid);
119 if (!on && !status)
120 return 0;
121
122 set_chp_logically_online(chpid, on);
123 chsc_chp_vary(chpid, on);
124 return 0;
125}
126
127/*
128 * Channel measurement related functions
129 */
130static ssize_t chp_measurement_chars_read(struct file *filp,
131 struct kobject *kobj,
132 struct bin_attribute *bin_attr,
133 char *buf, loff_t off, size_t count)
134{
135 struct channel_path *chp;
136 struct device *device;
137
138 device = kobj_to_dev(kobj);
139 chp = to_channelpath(device);
140 if (chp->cmg == -1)
141 return 0;
142
143 return memory_read_from_buffer(buf, count, &off, &chp->cmg_chars,
144 sizeof(chp->cmg_chars));
145}
146
147static const struct bin_attribute chp_measurement_chars_attr = {
148 .attr = {
149 .name = "measurement_chars",
150 .mode = S_IRUSR,
151 },
152 .size = sizeof(struct cmg_chars),
153 .read = chp_measurement_chars_read,
154};
155
156static void chp_measurement_copy_block(struct cmg_entry *buf,
157 struct channel_subsystem *css,
158 struct chp_id chpid)
159{
160 void *area;
161 struct cmg_entry *entry, reference_buf;
162 int idx;
163
164 if (chpid.id < 128) {
165 area = css->cub_addr1;
166 idx = chpid.id;
167 } else {
168 area = css->cub_addr2;
169 idx = chpid.id - 128;
170 }
171 entry = area + (idx * sizeof(struct cmg_entry));
172 do {
173 memcpy(buf, entry, sizeof(*entry));
174 memcpy(&reference_buf, entry, sizeof(*entry));
175 } while (reference_buf.values[0] != buf->values[0]);
176}
177
178static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj,
179 struct bin_attribute *bin_attr,
180 char *buf, loff_t off, size_t count)
181{
182 struct channel_path *chp;
183 struct channel_subsystem *css;
184 struct device *device;
185 unsigned int size;
186
187 device = kobj_to_dev(kobj);
188 chp = to_channelpath(device);
189 css = to_css(chp->dev.parent);
190
191 size = sizeof(struct cmg_entry);
192
193 /* Only allow single reads. */
194 if (off || count < size)
195 return 0;
196 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
197 count = size;
198 return count;
199}
200
201static const struct bin_attribute chp_measurement_attr = {
202 .attr = {
203 .name = "measurement",
204 .mode = S_IRUSR,
205 },
206 .size = sizeof(struct cmg_entry),
207 .read = chp_measurement_read,
208};
209
210void chp_remove_cmg_attr(struct channel_path *chp)
211{
212 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
213 device_remove_bin_file(&chp->dev, &chp_measurement_attr);
214}
215
216int chp_add_cmg_attr(struct channel_path *chp)
217{
218 int ret;
219
220 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
221 if (ret)
222 return ret;
223 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
224 if (ret)
225 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
226 return ret;
227}
228
229/*
230 * Files for the channel path entries.
231 */
232static ssize_t chp_status_show(struct device *dev,
233 struct device_attribute *attr, char *buf)
234{
235 struct channel_path *chp = to_channelpath(dev);
236 int status;
237
238 mutex_lock(&chp->lock);
239 status = chp->state;
240 mutex_unlock(&chp->lock);
241
242 return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n");
243}
244
245static ssize_t chp_status_write(struct device *dev,
246 struct device_attribute *attr,
247 const char *buf, size_t count)
248{
249 struct channel_path *cp = to_channelpath(dev);
250 char cmd[10];
251 int num_args;
252 int error;
253
254 num_args = sscanf(buf, "%5s", cmd);
255 if (!num_args)
256 return count;
257
258 /* Wait until previous actions have settled. */
259 css_wait_for_slow_path();
260
261 if (!strncasecmp(cmd, "on", 2) || !strcmp(cmd, "1")) {
262 mutex_lock(&cp->lock);
263 error = s390_vary_chpid(cp->chpid, 1);
264 mutex_unlock(&cp->lock);
265 } else if (!strncasecmp(cmd, "off", 3) || !strcmp(cmd, "0")) {
266 mutex_lock(&cp->lock);
267 error = s390_vary_chpid(cp->chpid, 0);
268 mutex_unlock(&cp->lock);
269 } else
270 error = -EINVAL;
271
272 return error < 0 ? error : count;
273}
274
275static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
276
277static ssize_t chp_configure_show(struct device *dev,
278 struct device_attribute *attr, char *buf)
279{
280 struct channel_path *cp;
281 int status;
282
283 cp = to_channelpath(dev);
284 status = chp_info_get_status(cp->chpid);
285 if (status < 0)
286 return status;
287
288 return sysfs_emit(buf, "%d\n", status);
289}
290
291static int cfg_wait_idle(void);
292
293static ssize_t chp_configure_write(struct device *dev,
294 struct device_attribute *attr,
295 const char *buf, size_t count)
296{
297 struct channel_path *cp;
298 int val;
299 char delim;
300
301 if (sscanf(buf, "%d %c", &val, &delim) != 1)
302 return -EINVAL;
303 if (val != 0 && val != 1)
304 return -EINVAL;
305 cp = to_channelpath(dev);
306 chp_cfg_schedule(cp->chpid, val);
307 cfg_wait_idle();
308
309 return count;
310}
311
312static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
313
314static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
315 char *buf)
316{
317 struct channel_path *chp = to_channelpath(dev);
318 u8 type;
319
320 mutex_lock(&chp->lock);
321 type = chp->desc.desc;
322 mutex_unlock(&chp->lock);
323 return sprintf(buf, "%x\n", type);
324}
325
326static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
327
328static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
329 char *buf)
330{
331 struct channel_path *chp = to_channelpath(dev);
332
333 if (!chp)
334 return 0;
335 if (chp->cmg == -1) /* channel measurements not available */
336 return sprintf(buf, "unknown\n");
337 return sprintf(buf, "%x\n", chp->cmg);
338}
339
340static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
341
342static ssize_t chp_shared_show(struct device *dev,
343 struct device_attribute *attr, char *buf)
344{
345 struct channel_path *chp = to_channelpath(dev);
346
347 if (!chp)
348 return 0;
349 if (chp->shared == -1) /* channel measurements not available */
350 return sprintf(buf, "unknown\n");
351 return sprintf(buf, "%x\n", chp->shared);
352}
353
354static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
355
356static ssize_t chp_chid_show(struct device *dev, struct device_attribute *attr,
357 char *buf)
358{
359 struct channel_path *chp = to_channelpath(dev);
360 ssize_t rc;
361
362 mutex_lock(&chp->lock);
363 if (chp->desc_fmt1.flags & 0x10)
364 rc = sprintf(buf, "%04x\n", chp->desc_fmt1.chid);
365 else
366 rc = 0;
367 mutex_unlock(&chp->lock);
368
369 return rc;
370}
371static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL);
372
373static ssize_t chp_chid_external_show(struct device *dev,
374 struct device_attribute *attr, char *buf)
375{
376 struct channel_path *chp = to_channelpath(dev);
377 ssize_t rc;
378
379 mutex_lock(&chp->lock);
380 if (chp->desc_fmt1.flags & 0x10)
381 rc = sprintf(buf, "%x\n", chp->desc_fmt1.flags & 0x8 ? 1 : 0);
382 else
383 rc = 0;
384 mutex_unlock(&chp->lock);
385
386 return rc;
387}
388static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL);
389
390static ssize_t chp_esc_show(struct device *dev,
391 struct device_attribute *attr, char *buf)
392{
393 struct channel_path *chp = to_channelpath(dev);
394 ssize_t rc;
395
396 mutex_lock(&chp->lock);
397 rc = sprintf(buf, "%x\n", chp->desc_fmt1.esc);
398 mutex_unlock(&chp->lock);
399
400 return rc;
401}
402static DEVICE_ATTR(esc, 0444, chp_esc_show, NULL);
403
404static ssize_t util_string_read(struct file *filp, struct kobject *kobj,
405 struct bin_attribute *attr, char *buf,
406 loff_t off, size_t count)
407{
408 struct channel_path *chp = to_channelpath(kobj_to_dev(kobj));
409 ssize_t rc;
410
411 mutex_lock(&chp->lock);
412 rc = memory_read_from_buffer(buf, count, &off, chp->desc_fmt3.util_str,
413 sizeof(chp->desc_fmt3.util_str));
414 mutex_unlock(&chp->lock);
415
416 return rc;
417}
418static BIN_ATTR_RO(util_string,
419 sizeof(((struct channel_path_desc_fmt3 *)0)->util_str));
420
421static struct bin_attribute *chp_bin_attrs[] = {
422 &bin_attr_util_string,
423 NULL,
424};
425
426static struct attribute *chp_attrs[] = {
427 &dev_attr_status.attr,
428 &dev_attr_configure.attr,
429 &dev_attr_type.attr,
430 &dev_attr_cmg.attr,
431 &dev_attr_shared.attr,
432 &dev_attr_chid.attr,
433 &dev_attr_chid_external.attr,
434 &dev_attr_esc.attr,
435 NULL,
436};
437static struct attribute_group chp_attr_group = {
438 .attrs = chp_attrs,
439 .bin_attrs = chp_bin_attrs,
440};
441static const struct attribute_group *chp_attr_groups[] = {
442 &chp_attr_group,
443 NULL,
444};
445
446static void chp_release(struct device *dev)
447{
448 struct channel_path *cp;
449
450 cp = to_channelpath(dev);
451 kfree(cp);
452}
453
454/**
455 * chp_update_desc - update channel-path description
456 * @chp: channel-path
457 *
458 * Update the channel-path description of the specified channel-path
459 * including channel measurement related information.
460 * Return zero on success, non-zero otherwise.
461 */
462int chp_update_desc(struct channel_path *chp)
463{
464 int rc;
465
466 rc = chsc_determine_fmt0_channel_path_desc(chp->chpid, &chp->desc);
467 if (rc)
468 return rc;
469
470 /*
471 * Fetching the following data is optional. Not all machines or
472 * hypervisors implement the required chsc commands.
473 */
474 chsc_determine_fmt1_channel_path_desc(chp->chpid, &chp->desc_fmt1);
475 chsc_determine_fmt3_channel_path_desc(chp->chpid, &chp->desc_fmt3);
476 chsc_get_channel_measurement_chars(chp);
477
478 return 0;
479}
480
481/**
482 * chp_new - register a new channel-path
483 * @chpid: channel-path ID
484 *
485 * Create and register data structure representing new channel-path. Return
486 * zero on success, non-zero otherwise.
487 */
488int chp_new(struct chp_id chpid)
489{
490 struct channel_subsystem *css = css_by_id(chpid.cssid);
491 struct channel_path *chp;
492 int ret = 0;
493
494 mutex_lock(&css->mutex);
495 if (chp_is_registered(chpid))
496 goto out;
497
498 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL);
499 if (!chp) {
500 ret = -ENOMEM;
501 goto out;
502 }
503 /* fill in status, etc. */
504 chp->chpid = chpid;
505 chp->state = 1;
506 chp->dev.parent = &css->device;
507 chp->dev.groups = chp_attr_groups;
508 chp->dev.release = chp_release;
509 mutex_init(&chp->lock);
510
511 /* Obtain channel path description and fill it in. */
512 ret = chp_update_desc(chp);
513 if (ret)
514 goto out_free;
515 if ((chp->desc.flags & 0x80) == 0) {
516 ret = -ENODEV;
517 goto out_free;
518 }
519 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id);
520
521 /* make it known to the system */
522 ret = device_register(&chp->dev);
523 if (ret) {
524 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n",
525 chpid.cssid, chpid.id, ret);
526 put_device(&chp->dev);
527 goto out;
528 }
529
530 if (css->cm_enabled) {
531 ret = chp_add_cmg_attr(chp);
532 if (ret) {
533 device_unregister(&chp->dev);
534 goto out;
535 }
536 }
537 css->chps[chpid.id] = chp;
538 goto out;
539out_free:
540 kfree(chp);
541out:
542 mutex_unlock(&css->mutex);
543 return ret;
544}
545
546/**
547 * chp_get_chp_desc - return newly allocated channel-path description
548 * @chpid: channel-path ID
549 *
550 * On success return a newly allocated copy of the channel-path description
551 * data associated with the given channel-path ID. Return %NULL on error.
552 */
553struct channel_path_desc_fmt0 *chp_get_chp_desc(struct chp_id chpid)
554{
555 struct channel_path *chp;
556 struct channel_path_desc_fmt0 *desc;
557
558 chp = chpid_to_chp(chpid);
559 if (!chp)
560 return NULL;
561 desc = kmalloc(sizeof(*desc), GFP_KERNEL);
562 if (!desc)
563 return NULL;
564
565 mutex_lock(&chp->lock);
566 memcpy(desc, &chp->desc, sizeof(*desc));
567 mutex_unlock(&chp->lock);
568 return desc;
569}
570
571/**
572 * chp_process_crw - process channel-path status change
573 * @crw0: channel report-word to handler
574 * @crw1: second channel-report word (always NULL)
575 * @overflow: crw overflow indication
576 *
577 * Handle channel-report-words indicating that the status of a channel-path
578 * has changed.
579 */
580static void chp_process_crw(struct crw *crw0, struct crw *crw1,
581 int overflow)
582{
583 struct chp_id chpid;
584
585 if (overflow) {
586 css_schedule_eval_all();
587 return;
588 }
589 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, "
590 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n",
591 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc,
592 crw0->erc, crw0->rsid);
593 /*
594 * Check for solicited machine checks. These are
595 * created by reset channel path and need not be
596 * handled here.
597 */
598 if (crw0->slct) {
599 CIO_CRW_EVENT(2, "solicited machine check for "
600 "channel path %02X\n", crw0->rsid);
601 return;
602 }
603 chp_id_init(&chpid);
604 chpid.id = crw0->rsid;
605 switch (crw0->erc) {
606 case CRW_ERC_IPARM: /* Path has come. */
607 case CRW_ERC_INIT:
608 chp_new(chpid);
609 chsc_chp_online(chpid);
610 break;
611 case CRW_ERC_PERRI: /* Path has gone. */
612 case CRW_ERC_PERRN:
613 chsc_chp_offline(chpid);
614 break;
615 default:
616 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n",
617 crw0->erc);
618 }
619}
620
621int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link)
622{
623 int i;
624 int mask;
625
626 for (i = 0; i < 8; i++) {
627 mask = 0x80 >> i;
628 if (!(ssd->path_mask & mask))
629 continue;
630 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid))
631 continue;
632 if ((ssd->fla_valid_mask & mask) &&
633 ((ssd->fla[i] & link->fla_mask) != link->fla))
634 continue;
635 return mask;
636 }
637 return 0;
638}
639EXPORT_SYMBOL_GPL(chp_ssd_get_mask);
640
641static inline int info_bit_num(struct chp_id id)
642{
643 return id.id + id.cssid * (__MAX_CHPID + 1);
644}
645
646/* Force chp_info refresh on next call to info_validate(). */
647static void info_expire(void)
648{
649 mutex_lock(&info_lock);
650 chp_info_expires = jiffies - 1;
651 mutex_unlock(&info_lock);
652}
653
654/* Ensure that chp_info is up-to-date. */
655static int info_update(void)
656{
657 int rc;
658
659 mutex_lock(&info_lock);
660 rc = 0;
661 if (time_after(jiffies, chp_info_expires)) {
662 /* Data is too old, update. */
663 rc = sclp_chp_read_info(&chp_info);
664 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ;
665 }
666 mutex_unlock(&info_lock);
667
668 return rc;
669}
670
671/**
672 * chp_info_get_status - retrieve configure status of a channel-path
673 * @chpid: channel-path ID
674 *
675 * On success, return 0 for standby, 1 for configured, 2 for reserved,
676 * 3 for not recognized. Return negative error code on error.
677 */
678int chp_info_get_status(struct chp_id chpid)
679{
680 int rc;
681 int bit;
682
683 rc = info_update();
684 if (rc)
685 return rc;
686
687 bit = info_bit_num(chpid);
688 mutex_lock(&info_lock);
689 if (!chp_test_bit(chp_info.recognized, bit))
690 rc = CHP_STATUS_NOT_RECOGNIZED;
691 else if (chp_test_bit(chp_info.configured, bit))
692 rc = CHP_STATUS_CONFIGURED;
693 else if (chp_test_bit(chp_info.standby, bit))
694 rc = CHP_STATUS_STANDBY;
695 else
696 rc = CHP_STATUS_RESERVED;
697 mutex_unlock(&info_lock);
698
699 return rc;
700}
701
702/* Return configure task for chpid. */
703static enum cfg_task_t cfg_get_task(struct chp_id chpid)
704{
705 return chp_cfg_task[chpid.cssid][chpid.id];
706}
707
708/* Set configure task for chpid. */
709static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg)
710{
711 chp_cfg_task[chpid.cssid][chpid.id] = cfg;
712}
713
714/* Fetch the first configure task. Set chpid accordingly. */
715static enum cfg_task_t chp_cfg_fetch_task(struct chp_id *chpid)
716{
717 enum cfg_task_t t = cfg_none;
718
719 chp_id_for_each(chpid) {
720 t = cfg_get_task(*chpid);
721 if (t != cfg_none)
722 break;
723 }
724
725 return t;
726}
727
728/* Perform one configure/deconfigure request. Reschedule work function until
729 * last request. */
730static void cfg_func(struct work_struct *work)
731{
732 struct chp_id chpid;
733 enum cfg_task_t t;
734 int rc;
735
736 spin_lock(&cfg_lock);
737 t = chp_cfg_fetch_task(&chpid);
738 spin_unlock(&cfg_lock);
739
740 switch (t) {
741 case cfg_configure:
742 rc = sclp_chp_configure(chpid);
743 if (rc)
744 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
745 "%d\n", chpid.cssid, chpid.id, rc);
746 else {
747 info_expire();
748 chsc_chp_online(chpid);
749 }
750 break;
751 case cfg_deconfigure:
752 rc = sclp_chp_deconfigure(chpid);
753 if (rc)
754 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
755 "%d\n", chpid.cssid, chpid.id, rc);
756 else {
757 info_expire();
758 chsc_chp_offline(chpid);
759 }
760 break;
761 case cfg_none:
762 /* Get updated information after last change. */
763 info_update();
764 wake_up_interruptible(&cfg_wait_queue);
765 return;
766 }
767 spin_lock(&cfg_lock);
768 if (t == cfg_get_task(chpid))
769 cfg_set_task(chpid, cfg_none);
770 spin_unlock(&cfg_lock);
771 schedule_work(&cfg_work);
772}
773
774/**
775 * chp_cfg_schedule - schedule chpid configuration request
776 * @chpid: channel-path ID
777 * @configure: Non-zero for configure, zero for deconfigure
778 *
779 * Schedule a channel-path configuration/deconfiguration request.
780 */
781void chp_cfg_schedule(struct chp_id chpid, int configure)
782{
783 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
784 configure);
785 spin_lock(&cfg_lock);
786 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
787 spin_unlock(&cfg_lock);
788 schedule_work(&cfg_work);
789}
790
791/**
792 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
793 * @chpid: channel-path ID
794 *
795 * Cancel an active channel-path deconfiguration request if it has not yet
796 * been performed.
797 */
798void chp_cfg_cancel_deconfigure(struct chp_id chpid)
799{
800 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
801 spin_lock(&cfg_lock);
802 if (cfg_get_task(chpid) == cfg_deconfigure)
803 cfg_set_task(chpid, cfg_none);
804 spin_unlock(&cfg_lock);
805}
806
807static bool cfg_idle(void)
808{
809 struct chp_id chpid;
810 enum cfg_task_t t;
811
812 spin_lock(&cfg_lock);
813 t = chp_cfg_fetch_task(&chpid);
814 spin_unlock(&cfg_lock);
815
816 return t == cfg_none;
817}
818
819static int cfg_wait_idle(void)
820{
821 if (wait_event_interruptible(cfg_wait_queue, cfg_idle()))
822 return -ERESTARTSYS;
823 return 0;
824}
825
826static int __init chp_init(void)
827{
828 struct chp_id chpid;
829 int state, ret;
830
831 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw);
832 if (ret)
833 return ret;
834 INIT_WORK(&cfg_work, cfg_func);
835 if (info_update())
836 return 0;
837 /* Register available channel-paths. */
838 chp_id_for_each(&chpid) {
839 state = chp_info_get_status(chpid);
840 if (state == CHP_STATUS_CONFIGURED ||
841 state == CHP_STATUS_STANDBY)
842 chp_new(chpid);
843 }
844
845 return 0;
846}
847
848subsys_initcall(chp_init);