1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Enclosure Services
4 *
5 * Copyright (C) 2008 James Bottomley <James.Bottomley@HansenPartnership.com>
6 *
7**-----------------------------------------------------------------------------
8**
9**
10**-----------------------------------------------------------------------------
11*/
12#include <linux/device.h>
13#include <linux/enclosure.h>
14#include <linux/err.h>
15#include <linux/list.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/mutex.h>
19#include <linux/slab.h>
20
21static LIST_HEAD(container_list);
22static DEFINE_MUTEX(container_list_lock);
23static struct class enclosure_class;
24
25/**
26 * enclosure_find - find an enclosure given a parent device
27 * @dev: the parent to match against
28 * @start: Optional enclosure device to start from (NULL if none)
29 *
30 * Looks through the list of registered enclosures to find all those
31 * with @dev as a parent. Returns NULL if no enclosure is
32 * found. @start can be used as a starting point to obtain multiple
33 * enclosures per parent (should begin with NULL and then be set to
34 * each returned enclosure device). Obtains a reference to the
35 * enclosure class device which must be released with put_device().
36 * If @start is not NULL, a reference must be taken on it which is
37 * released before returning (this allows a loop through all
38 * enclosures to exit with only the reference on the enclosure of
39 * interest held). Note that the @dev may correspond to the actual
40 * device housing the enclosure, in which case no iteration via @start
41 * is required.
42 */
43struct enclosure_device *enclosure_find(struct device *dev,
44 struct enclosure_device *start)
45{
46 struct enclosure_device *edev;
47
48 mutex_lock(&container_list_lock);
49 edev = list_prepare_entry(start, &container_list, node);
50 if (start)
51 put_device(dev: &start->edev);
52
53 list_for_each_entry_continue(edev, &container_list, node) {
54 struct device *parent = edev->edev.parent;
55 /* parent might not be immediate, so iterate up to
56 * the root of the tree if necessary */
57 while (parent) {
58 if (parent == dev) {
59 get_device(dev: &edev->edev);
60 mutex_unlock(lock: &container_list_lock);
61 return edev;
62 }
63 parent = parent->parent;
64 }
65 }
66 mutex_unlock(lock: &container_list_lock);
67
68 return NULL;
69}
70EXPORT_SYMBOL_GPL(enclosure_find);
71
72/**
73 * enclosure_for_each_device - calls a function for each enclosure
74 * @fn: the function to call
75 * @data: the data to pass to each call
76 *
77 * Loops over all the enclosures calling the function.
78 *
79 * Note, this function uses a mutex which will be held across calls to
80 * @fn, so it must have non atomic context, and @fn may (although it
81 * should not) sleep or otherwise cause the mutex to be held for
82 * indefinite periods
83 */
84int enclosure_for_each_device(int (*fn)(struct enclosure_device *, void *),
85 void *data)
86{
87 int error = 0;
88 struct enclosure_device *edev;
89
90 mutex_lock(&container_list_lock);
91 list_for_each_entry(edev, &container_list, node) {
92 error = fn(edev, data);
93 if (error)
94 break;
95 }
96 mutex_unlock(lock: &container_list_lock);
97
98 return error;
99}
100EXPORT_SYMBOL_GPL(enclosure_for_each_device);
101
102/**
103 * enclosure_register - register device as an enclosure
104 *
105 * @dev: device containing the enclosure
106 * @name: chosen device name
107 * @components: number of components in the enclosure
108 * @cb: platform call-backs
109 *
110 * This sets up the device for being an enclosure. Note that @dev does
111 * not have to be a dedicated enclosure device. It may be some other type
112 * of device that additionally responds to enclosure services
113 */
114struct enclosure_device *
115enclosure_register(struct device *dev, const char *name, int components,
116 struct enclosure_component_callbacks *cb)
117{
118 struct enclosure_device *edev =
119 kzalloc(struct_size(edev, component, components), GFP_KERNEL);
120 int err, i;
121
122 BUG_ON(!cb);
123
124 if (!edev)
125 return ERR_PTR(error: -ENOMEM);
126
127 edev->components = components;
128
129 edev->edev.class = &enclosure_class;
130 edev->edev.parent = get_device(dev);
131 edev->cb = cb;
132 dev_set_name(dev: &edev->edev, name: "%s", name);
133 err = device_register(dev: &edev->edev);
134 if (err)
135 goto err;
136
137 for (i = 0; i < components; i++) {
138 edev->component[i].number = -1;
139 edev->component[i].slot = -1;
140 edev->component[i].power_status = -1;
141 }
142
143 mutex_lock(&container_list_lock);
144 list_add_tail(new: &edev->node, head: &container_list);
145 mutex_unlock(lock: &container_list_lock);
146
147 return edev;
148
149 err:
150 put_device(dev: edev->edev.parent);
151 kfree(objp: edev);
152 return ERR_PTR(error: err);
153}
154EXPORT_SYMBOL_GPL(enclosure_register);
155
156static struct enclosure_component_callbacks enclosure_null_callbacks;
157
158/**
159 * enclosure_unregister - remove an enclosure
160 *
161 * @edev: the registered enclosure to remove;
162 */
163void enclosure_unregister(struct enclosure_device *edev)
164{
165 int i;
166
167 mutex_lock(&container_list_lock);
168 list_del(entry: &edev->node);
169 mutex_unlock(lock: &container_list_lock);
170
171 for (i = 0; i < edev->components; i++)
172 if (edev->component[i].number != -1)
173 device_unregister(dev: &edev->component[i].cdev);
174
175 /* prevent any callbacks into service user */
176 edev->cb = &enclosure_null_callbacks;
177 device_unregister(dev: &edev->edev);
178}
179EXPORT_SYMBOL_GPL(enclosure_unregister);
180
181#define ENCLOSURE_NAME_SIZE 64
182#define COMPONENT_NAME_SIZE 64
183
184static void enclosure_link_name(struct enclosure_component *cdev, char *name)
185{
186 strcpy(p: name, q: "enclosure_device:");
187 strcat(p: name, q: dev_name(dev: &cdev->cdev));
188}
189
190static void enclosure_remove_links(struct enclosure_component *cdev)
191{
192 char name[ENCLOSURE_NAME_SIZE];
193
194 enclosure_link_name(cdev, name);
195
196 /*
197 * In odd circumstances, like multipath devices, something else may
198 * already have removed the links, so check for this condition first.
199 */
200 if (cdev->dev->kobj.sd)
201 sysfs_remove_link(kobj: &cdev->dev->kobj, name);
202
203 if (cdev->cdev.kobj.sd)
204 sysfs_remove_link(kobj: &cdev->cdev.kobj, name: "device");
205}
206
207static int enclosure_add_links(struct enclosure_component *cdev)
208{
209 int error;
210 char name[ENCLOSURE_NAME_SIZE];
211
212 error = sysfs_create_link(kobj: &cdev->cdev.kobj, target: &cdev->dev->kobj, name: "device");
213 if (error)
214 return error;
215
216 enclosure_link_name(cdev, name);
217 error = sysfs_create_link(kobj: &cdev->dev->kobj, target: &cdev->cdev.kobj, name);
218 if (error)
219 sysfs_remove_link(kobj: &cdev->cdev.kobj, name: "device");
220
221 return error;
222}
223
224static void enclosure_release(struct device *cdev)
225{
226 struct enclosure_device *edev = to_enclosure_device(dev: cdev);
227
228 put_device(dev: cdev->parent);
229 kfree(objp: edev);
230}
231
232static void enclosure_component_release(struct device *dev)
233{
234 struct enclosure_component *cdev = to_enclosure_component(dev);
235
236 if (cdev->dev) {
237 enclosure_remove_links(cdev);
238 put_device(dev: cdev->dev);
239 }
240 put_device(dev: dev->parent);
241}
242
243static struct enclosure_component *
244enclosure_component_find_by_name(struct enclosure_device *edev,
245 const char *name)
246{
247 int i;
248 const char *cname;
249 struct enclosure_component *ecomp;
250
251 if (!edev || !name || !name[0])
252 return NULL;
253
254 for (i = 0; i < edev->components; i++) {
255 ecomp = &edev->component[i];
256 cname = dev_name(dev: &ecomp->cdev);
257 if (ecomp->number != -1 &&
258 cname && cname[0] &&
259 !strcmp(cname, name))
260 return ecomp;
261 }
262
263 return NULL;
264}
265
266static const struct attribute_group *enclosure_component_groups[];
267
268/**
269 * enclosure_component_alloc - prepare a new enclosure component
270 * @edev: the enclosure to add the component
271 * @number: the device number
272 * @type: the type of component being added
273 * @name: an optional name to appear in sysfs (leave NULL if none)
274 *
275 * The name is optional for enclosures that give their components a unique
276 * name. If not, leave the field NULL and a name will be assigned.
277 *
278 * Returns a pointer to the enclosure component or an error.
279 */
280struct enclosure_component *
281enclosure_component_alloc(struct enclosure_device *edev,
282 unsigned int number,
283 enum enclosure_component_type type,
284 const char *name)
285{
286 struct enclosure_component *ecomp;
287 struct device *cdev;
288 int i;
289 char newname[COMPONENT_NAME_SIZE];
290
291 if (number >= edev->components)
292 return ERR_PTR(error: -EINVAL);
293
294 ecomp = &edev->component[number];
295
296 if (ecomp->number != -1)
297 return ERR_PTR(error: -EINVAL);
298
299 ecomp->type = type;
300 ecomp->number = number;
301 cdev = &ecomp->cdev;
302 cdev->parent = get_device(dev: &edev->edev);
303
304 if (name && name[0]) {
305 /* Some hardware (e.g. enclosure in RX300 S6) has components
306 * with non unique names. Registering duplicates in sysfs
307 * will lead to warnings during bootup. So make the names
308 * unique by appending consecutive numbers -1, -2, ... */
309 i = 1;
310 snprintf(buf: newname, COMPONENT_NAME_SIZE,
311 fmt: "%s", name);
312 while (enclosure_component_find_by_name(edev, name: newname))
313 snprintf(buf: newname, COMPONENT_NAME_SIZE,
314 fmt: "%s-%i", name, i++);
315 dev_set_name(dev: cdev, name: "%s", newname);
316 } else
317 dev_set_name(dev: cdev, name: "%u", number);
318
319 cdev->release = enclosure_component_release;
320 cdev->groups = enclosure_component_groups;
321
322 return ecomp;
323}
324EXPORT_SYMBOL_GPL(enclosure_component_alloc);
325
326/**
327 * enclosure_component_register - publishes an initialized enclosure component
328 * @ecomp: component to add
329 *
330 * Returns 0 on successful registration, releases the component otherwise
331 */
332int enclosure_component_register(struct enclosure_component *ecomp)
333{
334 struct device *cdev;
335 int err;
336
337 cdev = &ecomp->cdev;
338 err = device_register(dev: cdev);
339 if (err) {
340 ecomp->number = -1;
341 put_device(dev: cdev);
342 return err;
343 }
344
345 return 0;
346}
347EXPORT_SYMBOL_GPL(enclosure_component_register);
348
349/**
350 * enclosure_add_device - add a device as being part of an enclosure
351 * @edev: the enclosure device being added to.
352 * @component: the number of the component
353 * @dev: the device being added
354 *
355 * Declares a real device to reside in slot (or identifier) @num of an
356 * enclosure. This will cause the relevant sysfs links to appear.
357 * This function may also be used to change a device associated with
358 * an enclosure without having to call enclosure_remove_device() in
359 * between.
360 *
361 * Returns zero on success or an error.
362 */
363int enclosure_add_device(struct enclosure_device *edev, int component,
364 struct device *dev)
365{
366 struct enclosure_component *cdev;
367 int err;
368
369 if (!edev || component >= edev->components)
370 return -EINVAL;
371
372 cdev = &edev->component[component];
373
374 if (cdev->dev == dev)
375 return -EEXIST;
376
377 if (cdev->dev) {
378 enclosure_remove_links(cdev);
379 put_device(dev: cdev->dev);
380 }
381 cdev->dev = get_device(dev);
382 err = enclosure_add_links(cdev);
383 if (err) {
384 put_device(dev: cdev->dev);
385 cdev->dev = NULL;
386 }
387 return err;
388}
389EXPORT_SYMBOL_GPL(enclosure_add_device);
390
391/**
392 * enclosure_remove_device - remove a device from an enclosure
393 * @edev: the enclosure device
394 * @dev: device to remove/put
395 *
396 * Returns zero on success or an error.
397 *
398 */
399int enclosure_remove_device(struct enclosure_device *edev, struct device *dev)
400{
401 struct enclosure_component *cdev;
402 int i;
403
404 if (!edev || !dev)
405 return -EINVAL;
406
407 for (i = 0; i < edev->components; i++) {
408 cdev = &edev->component[i];
409 if (cdev->dev == dev) {
410 enclosure_remove_links(cdev);
411 put_device(dev);
412 cdev->dev = NULL;
413 return 0;
414 }
415 }
416 return -ENODEV;
417}
418EXPORT_SYMBOL_GPL(enclosure_remove_device);
419
420/*
421 * sysfs pieces below
422 */
423
424static ssize_t components_show(struct device *cdev,
425 struct device_attribute *attr, char *buf)
426{
427 struct enclosure_device *edev = to_enclosure_device(dev: cdev);
428
429 return sysfs_emit(buf, fmt: "%d\n", edev->components);
430}
431static DEVICE_ATTR_RO(components);
432
433static ssize_t id_show(struct device *cdev,
434 struct device_attribute *attr,
435 char *buf)
436{
437 struct enclosure_device *edev = to_enclosure_device(dev: cdev);
438
439 if (edev->cb->show_id)
440 return edev->cb->show_id(edev, buf);
441 return -EINVAL;
442}
443static DEVICE_ATTR_RO(id);
444
445static struct attribute *enclosure_class_attrs[] = {
446 &dev_attr_components.attr,
447 &dev_attr_id.attr,
448 NULL,
449};
450ATTRIBUTE_GROUPS(enclosure_class);
451
452static struct class enclosure_class = {
453 .name = "enclosure",
454 .dev_release = enclosure_release,
455 .dev_groups = enclosure_class_groups,
456};
457
458static const char *const enclosure_status[] = {
459 [ENCLOSURE_STATUS_UNSUPPORTED] = "unsupported",
460 [ENCLOSURE_STATUS_OK] = "OK",
461 [ENCLOSURE_STATUS_CRITICAL] = "critical",
462 [ENCLOSURE_STATUS_NON_CRITICAL] = "non-critical",
463 [ENCLOSURE_STATUS_UNRECOVERABLE] = "unrecoverable",
464 [ENCLOSURE_STATUS_NOT_INSTALLED] = "not installed",
465 [ENCLOSURE_STATUS_UNKNOWN] = "unknown",
466 [ENCLOSURE_STATUS_UNAVAILABLE] = "unavailable",
467 [ENCLOSURE_STATUS_MAX] = NULL,
468};
469
470static const char *const enclosure_type[] = {
471 [ENCLOSURE_COMPONENT_DEVICE] = "device",
472 [ENCLOSURE_COMPONENT_ARRAY_DEVICE] = "array device",
473};
474
475static ssize_t get_component_fault(struct device *cdev,
476 struct device_attribute *attr, char *buf)
477{
478 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
479 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
480
481 if (edev->cb->get_fault)
482 edev->cb->get_fault(edev, ecomp);
483 return sysfs_emit(buf, fmt: "%d\n", ecomp->fault);
484}
485
486static ssize_t set_component_fault(struct device *cdev,
487 struct device_attribute *attr,
488 const char *buf, size_t count)
489{
490 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
491 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
492 int val = simple_strtoul(buf, NULL, 0);
493
494 if (edev->cb->set_fault)
495 edev->cb->set_fault(edev, ecomp, val);
496 return count;
497}
498
499static ssize_t get_component_status(struct device *cdev,
500 struct device_attribute *attr,char *buf)
501{
502 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
503 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
504
505 if (edev->cb->get_status)
506 edev->cb->get_status(edev, ecomp);
507 return sysfs_emit(buf, fmt: "%s\n", enclosure_status[ecomp->status]);
508}
509
510static ssize_t set_component_status(struct device *cdev,
511 struct device_attribute *attr,
512 const char *buf, size_t count)
513{
514 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
515 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
516 int i;
517
518 for (i = 0; enclosure_status[i]; i++) {
519 if (strncmp(buf, enclosure_status[i],
520 strlen(enclosure_status[i])) == 0 &&
521 (buf[strlen(enclosure_status[i])] == '\n' ||
522 buf[strlen(enclosure_status[i])] == '\0'))
523 break;
524 }
525
526 if (enclosure_status[i] && edev->cb->set_status) {
527 edev->cb->set_status(edev, ecomp, i);
528 return count;
529 } else
530 return -EINVAL;
531}
532
533static ssize_t get_component_active(struct device *cdev,
534 struct device_attribute *attr, char *buf)
535{
536 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
537 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
538
539 if (edev->cb->get_active)
540 edev->cb->get_active(edev, ecomp);
541 return sysfs_emit(buf, fmt: "%d\n", ecomp->active);
542}
543
544static ssize_t set_component_active(struct device *cdev,
545 struct device_attribute *attr,
546 const char *buf, size_t count)
547{
548 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
549 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
550 int val = simple_strtoul(buf, NULL, 0);
551
552 if (edev->cb->set_active)
553 edev->cb->set_active(edev, ecomp, val);
554 return count;
555}
556
557static ssize_t get_component_locate(struct device *cdev,
558 struct device_attribute *attr, char *buf)
559{
560 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
561 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
562
563 if (edev->cb->get_locate)
564 edev->cb->get_locate(edev, ecomp);
565 return sysfs_emit(buf, fmt: "%d\n", ecomp->locate);
566}
567
568static ssize_t set_component_locate(struct device *cdev,
569 struct device_attribute *attr,
570 const char *buf, size_t count)
571{
572 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
573 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
574 int val = simple_strtoul(buf, NULL, 0);
575
576 if (edev->cb->set_locate)
577 edev->cb->set_locate(edev, ecomp, val);
578 return count;
579}
580
581static ssize_t get_component_power_status(struct device *cdev,
582 struct device_attribute *attr,
583 char *buf)
584{
585 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
586 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
587
588 if (edev->cb->get_power_status)
589 edev->cb->get_power_status(edev, ecomp);
590
591 /* If still uninitialized, the callback failed or does not exist. */
592 if (ecomp->power_status == -1)
593 return (edev->cb->get_power_status) ? -EIO : -ENOTTY;
594
595 return sysfs_emit(buf, fmt: "%s\n", ecomp->power_status ? "on" : "off");
596}
597
598static ssize_t set_component_power_status(struct device *cdev,
599 struct device_attribute *attr,
600 const char *buf, size_t count)
601{
602 struct enclosure_device *edev = to_enclosure_device(dev: cdev->parent);
603 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
604 int val;
605
606 if (strncmp(buf, "on", 2) == 0 &&
607 (buf[2] == '\n' || buf[2] == '\0'))
608 val = 1;
609 else if (strncmp(buf, "off", 3) == 0 &&
610 (buf[3] == '\n' || buf[3] == '\0'))
611 val = 0;
612 else
613 return -EINVAL;
614
615 if (edev->cb->set_power_status)
616 edev->cb->set_power_status(edev, ecomp, val);
617 return count;
618}
619
620static ssize_t get_component_type(struct device *cdev,
621 struct device_attribute *attr, char *buf)
622{
623 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
624
625 return sysfs_emit(buf, fmt: "%s\n", enclosure_type[ecomp->type]);
626}
627
628static ssize_t get_component_slot(struct device *cdev,
629 struct device_attribute *attr, char *buf)
630{
631 struct enclosure_component *ecomp = to_enclosure_component(dev: cdev);
632 int slot;
633
634 /* if the enclosure does not override then use 'number' as a stand-in */
635 if (ecomp->slot >= 0)
636 slot = ecomp->slot;
637 else
638 slot = ecomp->number;
639
640 return sysfs_emit(buf, fmt: "%d\n", slot);
641}
642
643static DEVICE_ATTR(fault, S_IRUGO | S_IWUSR, get_component_fault,
644 set_component_fault);
645static DEVICE_ATTR(status, S_IRUGO | S_IWUSR, get_component_status,
646 set_component_status);
647static DEVICE_ATTR(active, S_IRUGO | S_IWUSR, get_component_active,
648 set_component_active);
649static DEVICE_ATTR(locate, S_IRUGO | S_IWUSR, get_component_locate,
650 set_component_locate);
651static DEVICE_ATTR(power_status, S_IRUGO | S_IWUSR, get_component_power_status,
652 set_component_power_status);
653static DEVICE_ATTR(type, S_IRUGO, get_component_type, NULL);
654static DEVICE_ATTR(slot, S_IRUGO, get_component_slot, NULL);
655
656static struct attribute *enclosure_component_attrs[] = {
657 &dev_attr_fault.attr,
658 &dev_attr_status.attr,
659 &dev_attr_active.attr,
660 &dev_attr_locate.attr,
661 &dev_attr_power_status.attr,
662 &dev_attr_type.attr,
663 &dev_attr_slot.attr,
664 NULL
665};
666ATTRIBUTE_GROUPS(enclosure_component);
667
668static int __init enclosure_init(void)
669{
670 return class_register(class: &enclosure_class);
671}
672
673static void __exit enclosure_exit(void)
674{
675 class_unregister(class: &enclosure_class);
676}
677
678module_init(enclosure_init);
679module_exit(enclosure_exit);
680
681MODULE_AUTHOR("James Bottomley");
682MODULE_DESCRIPTION("Enclosure Services");
683MODULE_LICENSE("GPL v2");
684

source code of linux/drivers/misc/enclosure.c