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 | |
33 | enum cfg_task_t { |
34 | cfg_none, |
35 | cfg_configure, |
36 | cfg_deconfigure |
37 | }; |
38 | |
39 | /* Map for pending configure tasks. */ |
40 | static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1]; |
41 | static DEFINE_SPINLOCK(cfg_lock); |
42 | |
43 | /* Map for channel-path status. */ |
44 | static struct sclp_chp_info chp_info; |
45 | static DEFINE_MUTEX(info_lock); |
46 | |
47 | /* Time after which channel-path status may be outdated. */ |
48 | static unsigned long chp_info_expires; |
49 | |
50 | static struct work_struct cfg_work; |
51 | |
52 | /* Wait queue for configure completion events. */ |
53 | static DECLARE_WAIT_QUEUE_HEAD(cfg_wait_queue); |
54 | |
55 | /* Set vary state for given chpid. */ |
56 | static void set_chp_logically_online(struct chp_id chpid, int onoff) |
57 | { |
58 | chpid_to_chp(chpid: 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. */ |
63 | int chp_get_status(struct chp_id chpid) |
64 | { |
65 | return (chpid_to_chp(chpid: chpid) ? chpid_to_chp(chpid: 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 | */ |
75 | u8 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: chpid) != 0) |
87 | opm |= 1; |
88 | } |
89 | return opm; |
90 | } |
91 | EXPORT_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 | */ |
100 | int chp_is_registered(struct chp_id chpid) |
101 | { |
102 | return chpid_to_chp(chpid: chpid) != NULL; |
103 | } |
104 | |
105 | /* |
106 | * Function: s390_vary_chpid |
107 | * Varies the specified chpid online or offline |
108 | */ |
109 | static int s390_vary_chpid(struct chp_id chpid, int on) |
110 | { |
111 | char dbf_text[15]; |
112 | int status; |
113 | |
114 | sprintf(buf: dbf_text, fmt: 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: chpid); |
119 | if (!on && !status) |
120 | return 0; |
121 | |
122 | set_chp_logically_online(chpid: chpid, onoff: on); |
123 | chsc_chp_vary(chpid: chpid, on); |
124 | return 0; |
125 | } |
126 | |
127 | /* |
128 | * Channel measurement related functions |
129 | */ |
130 | static 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(to: buf, count, ppos: &off, from: &chp->cmg_chars, |
144 | available: sizeof(chp->cmg_chars)); |
145 | } |
146 | |
147 | static 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 | |
156 | static 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 | |
178 | static 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(buf: (struct cmg_entry *)buf, css, chpid: chp->chpid); |
197 | count = size; |
198 | return count; |
199 | } |
200 | |
201 | static 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 | |
210 | void chp_remove_cmg_attr(struct channel_path *chp) |
211 | { |
212 | device_remove_bin_file(dev: &chp->dev, attr: &chp_measurement_chars_attr); |
213 | device_remove_bin_file(dev: &chp->dev, attr: &chp_measurement_attr); |
214 | } |
215 | |
216 | int chp_add_cmg_attr(struct channel_path *chp) |
217 | { |
218 | int ret; |
219 | |
220 | ret = device_create_bin_file(dev: &chp->dev, attr: &chp_measurement_chars_attr); |
221 | if (ret) |
222 | return ret; |
223 | ret = device_create_bin_file(dev: &chp->dev, attr: &chp_measurement_attr); |
224 | if (ret) |
225 | device_remove_bin_file(dev: &chp->dev, attr: &chp_measurement_chars_attr); |
226 | return ret; |
227 | } |
228 | |
229 | /* |
230 | * Files for the channel path entries. |
231 | */ |
232 | static 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(lock: &chp->lock); |
241 | |
242 | return status ? sprintf(buf, fmt: "online\n" ) : sprintf(buf, fmt: "offline\n" ); |
243 | } |
244 | |
245 | static 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(s1: cmd, s2: "on" , n: 2) || !strcmp(cmd, "1" )) { |
262 | mutex_lock(&cp->lock); |
263 | error = s390_vary_chpid(chpid: cp->chpid, on: 1); |
264 | mutex_unlock(lock: &cp->lock); |
265 | } else if (!strncasecmp(s1: cmd, s2: "off" , n: 3) || !strcmp(cmd, "0" )) { |
266 | mutex_lock(&cp->lock); |
267 | error = s390_vary_chpid(chpid: cp->chpid, on: 0); |
268 | mutex_unlock(lock: &cp->lock); |
269 | } else |
270 | error = -EINVAL; |
271 | |
272 | return error < 0 ? error : count; |
273 | } |
274 | |
275 | static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write); |
276 | |
277 | static 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(chpid: cp->chpid); |
285 | if (status < 0) |
286 | return status; |
287 | |
288 | return sysfs_emit(buf, fmt: "%d\n" , status); |
289 | } |
290 | |
291 | static int cfg_wait_idle(void); |
292 | |
293 | static 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(chpid: cp->chpid, configure: val); |
307 | cfg_wait_idle(); |
308 | |
309 | return count; |
310 | } |
311 | |
312 | static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write); |
313 | |
314 | static 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(lock: &chp->lock); |
323 | return sprintf(buf, fmt: "%x\n" , type); |
324 | } |
325 | |
326 | static DEVICE_ATTR(type, 0444, chp_type_show, NULL); |
327 | |
328 | static 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, fmt: "unknown\n" ); |
337 | return sprintf(buf, fmt: "%d\n" , chp->cmg); |
338 | } |
339 | |
340 | static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL); |
341 | |
342 | static 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, fmt: "unknown\n" ); |
351 | return sprintf(buf, fmt: "%x\n" , chp->shared); |
352 | } |
353 | |
354 | static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL); |
355 | |
356 | static 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, fmt: "%04x\n" , chp->desc_fmt1.chid); |
365 | else |
366 | rc = 0; |
367 | mutex_unlock(lock: &chp->lock); |
368 | |
369 | return rc; |
370 | } |
371 | static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL); |
372 | |
373 | static 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, fmt: "%x\n" , chp->desc_fmt1.flags & 0x8 ? 1 : 0); |
382 | else |
383 | rc = 0; |
384 | mutex_unlock(lock: &chp->lock); |
385 | |
386 | return rc; |
387 | } |
388 | static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL); |
389 | |
390 | static 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, fmt: "%x\n" , chp->desc_fmt1.esc); |
398 | mutex_unlock(lock: &chp->lock); |
399 | |
400 | return rc; |
401 | } |
402 | static DEVICE_ATTR(esc, 0444, chp_esc_show, NULL); |
403 | |
404 | static 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(to: buf, count, ppos: &off, from: chp->desc_fmt3.util_str, |
413 | available: sizeof(chp->desc_fmt3.util_str)); |
414 | mutex_unlock(lock: &chp->lock); |
415 | |
416 | return rc; |
417 | } |
418 | static BIN_ATTR_RO(util_string, |
419 | sizeof(((struct channel_path_desc_fmt3 *)0)->util_str)); |
420 | |
421 | static struct bin_attribute *chp_bin_attrs[] = { |
422 | &bin_attr_util_string, |
423 | NULL, |
424 | }; |
425 | |
426 | static 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 | }; |
437 | static struct attribute_group chp_attr_group = { |
438 | .attrs = chp_attrs, |
439 | .bin_attrs = chp_bin_attrs, |
440 | }; |
441 | static const struct attribute_group *chp_attr_groups[] = { |
442 | &chp_attr_group, |
443 | NULL, |
444 | }; |
445 | |
446 | static void chp_release(struct device *dev) |
447 | { |
448 | struct channel_path *cp; |
449 | |
450 | cp = to_channelpath(dev); |
451 | kfree(objp: 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 | */ |
462 | int chp_update_desc(struct channel_path *chp) |
463 | { |
464 | int rc; |
465 | |
466 | rc = chsc_determine_fmt0_channel_path_desc(chpid: chp->chpid, desc: &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(chpid: chp->chpid, desc: &chp->desc_fmt1); |
475 | chsc_determine_fmt3_channel_path_desc(chpid: chp->chpid, desc: &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 | */ |
488 | int chp_new(struct chp_id chpid) |
489 | { |
490 | struct channel_subsystem *css = css_by_id(cssid: chpid.cssid); |
491 | struct channel_path *chp; |
492 | int ret = 0; |
493 | |
494 | mutex_lock(&css->mutex); |
495 | if (chp_is_registered(chpid: chpid)) |
496 | goto out; |
497 | |
498 | chp = kzalloc(size: 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(dev: &chp->dev, name: "chp%x.%02x" , chpid.cssid, chpid.id); |
520 | |
521 | /* make it known to the system */ |
522 | ret = device_register(dev: &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(dev: &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(dev: &chp->dev); |
534 | goto out; |
535 | } |
536 | } |
537 | css->chps[chpid.id] = chp; |
538 | goto out; |
539 | out_free: |
540 | kfree(objp: chp); |
541 | out: |
542 | mutex_unlock(lock: &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 | */ |
553 | struct 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: 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(lock: &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 | */ |
580 | static 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: chpid); |
609 | chsc_chp_online(chpid: chpid); |
610 | break; |
611 | case CRW_ERC_PERRI: /* Path has gone. */ |
612 | case CRW_ERC_PERRN: |
613 | chsc_chp_offline(chpid: 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 | |
621 | int 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 | } |
639 | EXPORT_SYMBOL_GPL(chp_ssd_get_mask); |
640 | |
641 | static 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(). */ |
647 | static void info_expire(void) |
648 | { |
649 | mutex_lock(&info_lock); |
650 | chp_info_expires = jiffies - 1; |
651 | mutex_unlock(lock: &info_lock); |
652 | } |
653 | |
654 | /* Ensure that chp_info is up-to-date. */ |
655 | static 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(lock: &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 | */ |
678 | int 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(id: chpid); |
688 | mutex_lock(&info_lock); |
689 | if (!chp_test_bit(bitmap: chp_info.recognized, num: bit)) |
690 | rc = CHP_STATUS_NOT_RECOGNIZED; |
691 | else if (chp_test_bit(bitmap: chp_info.configured, num: bit)) |
692 | rc = CHP_STATUS_CONFIGURED; |
693 | else if (chp_test_bit(bitmap: chp_info.standby, num: bit)) |
694 | rc = CHP_STATUS_STANDBY; |
695 | else |
696 | rc = CHP_STATUS_RESERVED; |
697 | mutex_unlock(lock: &info_lock); |
698 | |
699 | return rc; |
700 | } |
701 | |
702 | /* Return configure task for chpid. */ |
703 | static 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. */ |
709 | static 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. */ |
715 | static 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. */ |
730 | static 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(lock: &cfg_lock); |
737 | t = chp_cfg_fetch_task(chpid: &chpid); |
738 | spin_unlock(lock: &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: 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: 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(lock: &cfg_lock); |
768 | if (t == cfg_get_task(chpid: chpid)) |
769 | cfg_set_task(chpid: chpid, cfg: cfg_none); |
770 | spin_unlock(lock: &cfg_lock); |
771 | schedule_work(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 | */ |
781 | void 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(lock: &cfg_lock); |
786 | cfg_set_task(chpid: chpid, cfg: configure ? cfg_configure : cfg_deconfigure); |
787 | spin_unlock(lock: &cfg_lock); |
788 | schedule_work(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 | */ |
798 | void 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(lock: &cfg_lock); |
802 | if (cfg_get_task(chpid: chpid) == cfg_deconfigure) |
803 | cfg_set_task(chpid: chpid, cfg: cfg_none); |
804 | spin_unlock(lock: &cfg_lock); |
805 | } |
806 | |
807 | static bool cfg_idle(void) |
808 | { |
809 | struct chp_id chpid; |
810 | enum cfg_task_t t; |
811 | |
812 | spin_lock(lock: &cfg_lock); |
813 | t = chp_cfg_fetch_task(chpid: &chpid); |
814 | spin_unlock(lock: &cfg_lock); |
815 | |
816 | return t == cfg_none; |
817 | } |
818 | |
819 | static int cfg_wait_idle(void) |
820 | { |
821 | if (wait_event_interruptible(cfg_wait_queue, cfg_idle())) |
822 | return -ERESTARTSYS; |
823 | return 0; |
824 | } |
825 | |
826 | static 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: chpid); |
840 | if (state == CHP_STATUS_CONFIGURED || |
841 | state == CHP_STATUS_STANDBY) |
842 | chp_new(chpid: chpid); |
843 | } |
844 | |
845 | return 0; |
846 | } |
847 | |
848 | subsys_initcall(chp_init); |
849 | |