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47/* Time after which channel-path status may be outdated.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