projects/linux·blob assoc-array-fixes · refs

1348 lines · 34.1 KiB

1// SPDX-License-Identifier: GPL-2.0
2/*
3 * drivers/base/devres.c - device resource management
4 *
5 * Copyright (c) 2006 SUSE Linux Products GmbH
6 * Copyright (c) 2006 Tejun Heo <[email protected]>
7 */
8
9#include <linux/device.h>
10#include <linux/module.h>
11#include <linux/slab.h>
12#include <linux/percpu.h>
13
14#include <asm/sections.h>
15
16#include "base.h"
17#include "trace.h"
18
19struct devres {
20 struct devres_node node;
21 dr_release_t release;
22 /*
23 * Some archs want to perform DMA into kmalloc caches
24 * and need a guaranteed alignment larger than
25 * the alignment of a 64-bit integer.
26 * Thus we use ARCH_DMA_MINALIGN for data[] which will force the same
27 * alignment for struct devres when allocated by kmalloc().
28 */
29 u8 __aligned(ARCH_DMA_MINALIGN) data[];
30};
31
32struct devres_group {
33 struct devres_node node[2];
34 void *id;
35 int color;
36 /* -- 8 pointers */
37};
38
39void devres_node_init(struct devres_node *node,
40 dr_node_release_t release,
41 dr_node_free_t free_node)
42{
43 INIT_LIST_HEAD(&node->entry);
44 node->release = release;
45 node->free_node = free_node;
46}
47
48static inline void free_node(struct devres_node *node)
49{
50 node->free_node(node);
51}
52
53void devres_set_node_dbginfo(struct devres_node *node, const char *name,
54 size_t size)
55{
56 node->name = name;
57 node->size = size;
58}
59
60#ifdef CONFIG_DEBUG_DEVRES
61static int log_devres = 0;
62module_param_named(log, log_devres, int, S_IRUGO | S_IWUSR);
63
64static void devres_dbg(struct device *dev, struct devres_node *node,
65 const char *op)
66{
67 if (unlikely(log_devres))
68 dev_err(dev, "DEVRES %3s %p %s (%zu bytes)\n",
69 op, node, node->name, node->size);
70}
71#else /* CONFIG_DEBUG_DEVRES */
72#define devres_dbg(dev, node, op) do {} while (0)
73#endif /* CONFIG_DEBUG_DEVRES */
74
75static void devres_log(struct device *dev, struct devres_node *node,
76 const char *op)
77{
78 trace_devres_log(dev, op, node, node->name, node->size);
79 devres_dbg(dev, node, op);
80}
81
82/*
83 * Release functions for devres group. These callbacks are used only
84 * for identification.
85 */
86static void group_open_release(struct device *dev, struct devres_node *node)
87{
88 /* noop */
89}
90
91static void group_close_release(struct device *dev, struct devres_node *node)
92{
93 /* noop */
94}
95
96static struct devres_group *node_to_group(struct devres_node *node)
97{
98 if (node->release == &group_open_release)
99 return container_of(node, struct devres_group, node[0]);
100 if (node->release == &group_close_release)
101 return container_of(node, struct devres_group, node[1]);
102 return NULL;
103}
104
105static bool check_dr_size(size_t size, size_t *tot_size)
106{
107 /* We must catch any near-SIZE_MAX cases that could overflow. */
108 if (unlikely(check_add_overflow(sizeof(struct devres),
109 size, tot_size)))
110 return false;
111
112 /* Actually allocate the full kmalloc bucket size. */
113 *tot_size = kmalloc_size_roundup(*tot_size);
114
115 return true;
116}
117
118static void dr_node_release(struct device *dev, struct devres_node *node)
119{
120 struct devres *dr = container_of(node, struct devres, node);
121
122 dr->release(dev, dr->data);
123}
124
125static void dr_node_free(struct devres_node *node)
126{
127 struct devres *dr = container_of(node, struct devres, node);
128
129 kfree(dr);
130}
131
132static __always_inline struct devres *alloc_dr(dr_release_t release,
133 size_t size, gfp_t gfp, int nid)
134{
135 size_t tot_size;
136 struct devres *dr;
137
138 if (!check_dr_size(size, &tot_size))
139 return NULL;
140
141 dr = kmalloc_node_track_caller(tot_size, gfp, nid);
142 if (unlikely(!dr))
143 return NULL;
144
145 /* No need to clear memory twice */
146 if (!(gfp & __GFP_ZERO))
147 memset(dr, 0, offsetof(struct devres, data));
148
149 devres_node_init(&dr->node, dr_node_release, dr_node_free);
150 dr->release = release;
151 return dr;
152}
153
154static void add_dr(struct device *dev, struct devres_node *node)
155{
156 devres_log(dev, node, "ADD");
157 BUG_ON(!list_empty(&node->entry));
158 list_add_tail(&node->entry, &dev->devres_head);
159}
160
161static void replace_dr(struct device *dev,
162 struct devres_node *old, struct devres_node *new)
163{
164 devres_log(dev, old, "REPLACE");
165 BUG_ON(!list_empty(&new->entry));
166 list_replace(&old->entry, &new->entry);
167}
168
169/**
170 * __devres_alloc_node - Allocate device resource data
171 * @release: Release function devres will be associated with
172 * @size: Allocation size
173 * @gfp: Allocation flags
174 * @nid: NUMA node
175 * @name: Name of the resource
176 *
177 * Allocate devres of @size bytes. The allocated area is zeroed, then
178 * associated with @release. The returned pointer can be passed to
179 * other devres_*() functions.
180 *
181 * RETURNS:
182 * Pointer to allocated devres on success, NULL on failure.
183 */
184void *__devres_alloc_node(dr_release_t release, size_t size, gfp_t gfp, int nid,
185 const char *name)
186{
187 struct devres *dr;
188
189 dr = alloc_dr(release, size, gfp | __GFP_ZERO, nid);
190 if (unlikely(!dr))
191 return NULL;
192 devres_set_node_dbginfo(&dr->node, name, size);
193 return dr->data;
194}
195EXPORT_SYMBOL_GPL(__devres_alloc_node);
196
197/**
198 * devres_for_each_res - Resource iterator
199 * @dev: Device to iterate resource from
200 * @release: Look for resources associated with this release function
201 * @match: Match function (optional)
202 * @match_data: Data for the match function
203 * @fn: Function to be called for each matched resource.
204 * @data: Data for @fn, the 3rd parameter of @fn
205 *
206 * Call @fn for each devres of @dev which is associated with @release
207 * and for which @match returns 1.
208 *
209 * RETURNS:
210 * void
211 */
212void devres_for_each_res(struct device *dev, dr_release_t release,
213 dr_match_t match, void *match_data,
214 void (*fn)(struct device *, void *, void *),
215 void *data)
216{
217 struct devres_node *node;
218 struct devres_node *tmp;
219
220 if (!fn)
221 return;
222
223 guard(spinlock_irqsave)(&dev->devres_lock);
224 list_for_each_entry_safe_reverse(node, tmp,
225 &dev->devres_head, entry) {
226 struct devres *dr = container_of(node, struct devres, node);
227
228 if (node->release != dr_node_release)
229 continue;
230 if (dr->release != release)
231 continue;
232 if (match && !match(dev, dr->data, match_data))
233 continue;
234 fn(dev, dr->data, data);
235 }
236}
237EXPORT_SYMBOL_GPL(devres_for_each_res);
238
239static inline void free_dr(struct devres *dr)
240{
241 free_node(&dr->node);
242}
243
244/**
245 * devres_free - Free device resource data
246 * @res: Pointer to devres data to free
247 *
248 * Free devres created with devres_alloc().
249 */
250void devres_free(void *res)
251{
252 if (res) {
253 struct devres *dr = container_of(res, struct devres, data);
254
255 BUG_ON(!list_empty(&dr->node.entry));
256 free_dr(dr);
257 }
258}
259EXPORT_SYMBOL_GPL(devres_free);
260
261void devres_node_add(struct device *dev, struct devres_node *node)
262{
263 guard(spinlock_irqsave)(&dev->devres_lock);
264
265 add_dr(dev, node);
266}
267
268/**
269 * devres_add - Register device resource
270 * @dev: Device to add resource to
271 * @res: Resource to register
272 *
273 * Register devres @res to @dev. @res should have been allocated
274 * using devres_alloc(). On driver detach, the associated release
275 * function will be invoked and devres will be freed automatically.
276 */
277void devres_add(struct device *dev, void *res)
278{
279 struct devres *dr = container_of(res, struct devres, data);
280
281 devres_node_add(dev, &dr->node);
282}
283EXPORT_SYMBOL_GPL(devres_add);
284
285static struct devres *find_dr(struct device *dev, dr_release_t release,
286 dr_match_t match, void *match_data)
287{
288 struct devres_node *node;
289
290 list_for_each_entry_reverse(node, &dev->devres_head, entry) {
291 struct devres *dr = container_of(node, struct devres, node);
292
293 if (node->release != dr_node_release)
294 continue;
295 if (dr->release != release)
296 continue;
297 if (match && !match(dev, dr->data, match_data))
298 continue;
299 return dr;
300 }
301
302 return NULL;
303}
304
305/**
306 * devres_find - Find device resource
307 * @dev: Device to lookup resource from
308 * @release: Look for resources associated with this release function
309 * @match: Match function (optional)
310 * @match_data: Data for the match function
311 *
312 * Find the latest devres of @dev which is associated with @release
313 * and for which @match returns 1. If @match is NULL, it's considered
314 * to match all.
315 *
316 * RETURNS:
317 * Pointer to found devres, NULL if not found.
318 */
319void *devres_find(struct device *dev, dr_release_t release,
320 dr_match_t match, void *match_data)
321{
322 struct devres *dr;
323
324 guard(spinlock_irqsave)(&dev->devres_lock);
325 dr = find_dr(dev, release, match, match_data);
326 if (dr)
327 return dr->data;
328
329 return NULL;
330}
331EXPORT_SYMBOL_GPL(devres_find);
332
333/**
334 * devres_get - Find devres, if non-existent, add one atomically
335 * @dev: Device to lookup or add devres for
336 * @new_res: Pointer to new initialized devres to add if not found
337 * @match: Match function (optional)
338 * @match_data: Data for the match function
339 *
340 * Find the latest devres of @dev which has the same release function
341 * as @new_res and for which @match return 1. If found, @new_res is
342 * freed; otherwise, @new_res is added atomically.
343 *
344 * RETURNS:
345 * Pointer to found or added devres.
346 */
347void *devres_get(struct device *dev, void *new_res,
348 dr_match_t match, void *match_data)
349{
350 struct devres *new_dr = container_of(new_res, struct devres, data);
351 struct devres *dr;
352 unsigned long flags;
353
354 spin_lock_irqsave(&dev->devres_lock, flags);
355 dr = find_dr(dev, new_dr->release, match, match_data);
356 if (!dr) {
357 add_dr(dev, &new_dr->node);
358 dr = new_dr;
359 new_res = NULL;
360 }
361 spin_unlock_irqrestore(&dev->devres_lock, flags);
362 devres_free(new_res);
363
364 return dr->data;
365}
366EXPORT_SYMBOL_GPL(devres_get);
367
368bool devres_node_remove(struct device *dev, struct devres_node *node)
369{
370 struct devres_node *__node;
371
372 guard(spinlock_irqsave)(&dev->devres_lock);
373 list_for_each_entry_reverse(__node, &dev->devres_head, entry) {
374 if (__node == node) {
375 list_del_init(&node->entry);
376 devres_log(dev, node, "REM");
377 return true;
378 }
379 }
380
381 return false;
382}
383
384/**
385 * devres_remove - Find a device resource and remove it
386 * @dev: Device to find resource from
387 * @release: Look for resources associated with this release function
388 * @match: Match function (optional)
389 * @match_data: Data for the match function
390 *
391 * Find the latest devres of @dev associated with @release and for
392 * which @match returns 1. If @match is NULL, it's considered to
393 * match all. If found, the resource is removed atomically and
394 * returned.
395 *
396 * RETURNS:
397 * Pointer to removed devres on success, NULL if not found.
398 */
399void *devres_remove(struct device *dev, dr_release_t release,
400 dr_match_t match, void *match_data)
401{
402 struct devres *dr;
403
404 guard(spinlock_irqsave)(&dev->devres_lock);
405 dr = find_dr(dev, release, match, match_data);
406 if (dr) {
407 list_del_init(&dr->node.entry);
408 devres_log(dev, &dr->node, "REM");
409 return dr->data;
410 }
411
412 return NULL;
413}
414EXPORT_SYMBOL_GPL(devres_remove);
415
416/**
417 * devres_destroy - Find a device resource and destroy it
418 * @dev: Device to find resource from
419 * @release: Look for resources associated with this release function
420 * @match: Match function (optional)
421 * @match_data: Data for the match function
422 *
423 * Find the latest devres of @dev associated with @release and for
424 * which @match returns 1. If @match is NULL, it's considered to
425 * match all. If found, the resource is removed atomically and freed.
426 *
427 * Note that the release function for the resource will not be called,
428 * only the devres-allocated data will be freed. The caller becomes
429 * responsible for freeing any other data.
430 *
431 * RETURNS:
432 * 0 if devres is found and freed, -ENOENT if not found.
433 */
434int devres_destroy(struct device *dev, dr_release_t release,
435 dr_match_t match, void *match_data)
436{
437 void *res;
438
439 res = devres_remove(dev, release, match, match_data);
440 if (unlikely(!res))
441 return -ENOENT;
442
443 devres_free(res);
444 return 0;
445}
446EXPORT_SYMBOL_GPL(devres_destroy);
447
448
449/**
450 * devres_release - Find a device resource and destroy it, calling release
451 * @dev: Device to find resource from
452 * @release: Look for resources associated with this release function
453 * @match: Match function (optional)
454 * @match_data: Data for the match function
455 *
456 * Find the latest devres of @dev associated with @release and for
457 * which @match returns 1. If @match is NULL, it's considered to
458 * match all. If found, the resource is removed atomically, the
459 * release function called and the resource freed.
460 *
461 * RETURNS:
462 * 0 if devres is found and freed, -ENOENT if not found.
463 */
464int devres_release(struct device *dev, dr_release_t release,
465 dr_match_t match, void *match_data)
466{
467 void *res;
468
469 res = devres_remove(dev, release, match, match_data);
470 if (unlikely(!res))
471 return -ENOENT;
472
473 (*release)(dev, res);
474 devres_free(res);
475 return 0;
476}
477EXPORT_SYMBOL_GPL(devres_release);
478
479static int remove_nodes(struct device *dev,
480 struct list_head *first, struct list_head *end,
481 struct list_head *todo)
482{
483 struct devres_node *node, *n;
484 int cnt = 0, nr_groups = 0;
485
486 /* First pass - move normal devres entries to @todo and clear
487 * devres_group colors.
488 */
489 node = list_entry(first, struct devres_node, entry);
490 list_for_each_entry_safe_from(node, n, end, entry) {
491 struct devres_group *grp;
492
493 grp = node_to_group(node);
494 if (grp) {
495 /* clear color of group markers in the first pass */
496 grp->color = 0;
497 nr_groups++;
498 } else {
499 /* regular devres entry */
500 if (&node->entry == first)
501 first = first->next;
502 list_move_tail(&node->entry, todo);
503 cnt++;
504 }
505 }
506
507 if (!nr_groups)
508 return cnt;
509
510 /* Second pass - Scan groups and color them. A group gets
511 * color value of two iff the group is wholly contained in
512 * [current node, end). That is, for a closed group, both opening
513 * and closing markers should be in the range, while just the
514 * opening marker is enough for an open group.
515 */
516 node = list_entry(first, struct devres_node, entry);
517 list_for_each_entry_safe_from(node, n, end, entry) {
518 struct devres_group *grp;
519
520 grp = node_to_group(node);
521 BUG_ON(!grp || list_empty(&grp->node[0].entry));
522
523 grp->color++;
524 if (list_empty(&grp->node[1].entry))
525 grp->color++;
526
527 BUG_ON(grp->color <= 0 || grp->color > 2);
528 if (grp->color == 2) {
529 /* No need to update current node or end. The removed
530 * nodes are always before both.
531 */
532 list_move_tail(&grp->node[0].entry, todo);
533 list_del_init(&grp->node[1].entry);
534 }
535 }
536
537 return cnt;
538}
539
540static void release_nodes(struct device *dev, struct list_head *todo)
541{
542 struct devres_node *node, *tmp;
543
544 list_for_each_entry_safe_reverse(node, tmp, todo, entry) {
545 devres_log(dev, node, "REL");
546 node->release(dev, node);
547 free_node(node);
548 }
549}
550
551/**
552 * devres_release_all - Release all managed resources
553 * @dev: Device to release resources for
554 *
555 * Release all resources associated with @dev. This function is
556 * called on driver detach.
557 */
558int devres_release_all(struct device *dev)
559{
560 unsigned long flags;
561 LIST_HEAD(todo);
562 int cnt;
563
564 /* Looks like an uninitialized device structure */
565 if (WARN_ON(dev->devres_head.next == NULL))
566 return -ENODEV;
567
568 /* Nothing to release if list is empty */
569 if (list_empty(&dev->devres_head))
570 return 0;
571
572 spin_lock_irqsave(&dev->devres_lock, flags);
573 cnt = remove_nodes(dev, dev->devres_head.next, &dev->devres_head, &todo);
574 spin_unlock_irqrestore(&dev->devres_lock, flags);
575
576 release_nodes(dev, &todo);
577 return cnt;
578}
579
580static void devres_group_free(struct devres_node *node)
581{
582 struct devres_group *grp = container_of(node, struct devres_group, node[0]);
583
584 kfree(grp);
585}
586
587/**
588 * devres_open_group - Open a new devres group
589 * @dev: Device to open devres group for
590 * @id: Separator ID
591 * @gfp: Allocation flags
592 *
593 * Open a new devres group for @dev with @id. For @id, using a
594 * pointer to an object which won't be used for another group is
595 * recommended. If @id is NULL, address-wise unique ID is created.
596 *
597 * RETURNS:
598 * ID of the new group, NULL on failure.
599 */
600void *devres_open_group(struct device *dev, void *id, gfp_t gfp)
601{
602 struct devres_group *grp;
603
604 grp = kmalloc_obj(*grp, gfp);
605 if (unlikely(!grp))
606 return NULL;
607
608 devres_node_init(&grp->node[0], &group_open_release, devres_group_free);
609 devres_node_init(&grp->node[1], &group_close_release, NULL);
610 devres_set_node_dbginfo(&grp->node[0], "grp<", 0);
611 devres_set_node_dbginfo(&grp->node[1], "grp>", 0);
612 grp->id = grp;
613 if (id)
614 grp->id = id;
615 grp->color = 0;
616
617 devres_node_add(dev, &grp->node[0]);
618 return grp->id;
619}
620EXPORT_SYMBOL_GPL(devres_open_group);
621
622/*
623 * Find devres group with ID @id. If @id is NULL, look for the latest open
624 * group.
625 */
626static struct devres_group *find_group(struct device *dev, void *id)
627{
628 struct devres_node *node;
629
630 list_for_each_entry_reverse(node, &dev->devres_head, entry) {
631 struct devres_group *grp;
632
633 if (node->release != &group_open_release)
634 continue;
635
636 grp = container_of(node, struct devres_group, node[0]);
637
638 if (id) {
639 if (grp->id == id)
640 return grp;
641 } else if (list_empty(&grp->node[1].entry))
642 return grp;
643 }
644
645 return NULL;
646}
647
648/**
649 * devres_close_group - Close a devres group
650 * @dev: Device to close devres group for
651 * @id: ID of target group, can be NULL
652 *
653 * Close the group identified by @id. If @id is NULL, the latest open
654 * group is selected.
655 */
656void devres_close_group(struct device *dev, void *id)
657{
658 struct devres_group *grp;
659
660 guard(spinlock_irqsave)(&dev->devres_lock);
661 grp = find_group(dev, id);
662 if (grp)
663 add_dr(dev, &grp->node[1]);
664 else
665 WARN_ON(1);
666}
667EXPORT_SYMBOL_GPL(devres_close_group);
668
669/**
670 * devres_remove_group - Remove a devres group
671 * @dev: Device to remove group for
672 * @id: ID of target group, can be NULL
673 *
674 * Remove the group identified by @id. If @id is NULL, the latest
675 * open group is selected. Note that removing a group doesn't affect
676 * any other resources.
677 */
678void devres_remove_group(struct device *dev, void *id)
679{
680 struct devres_group *grp;
681 unsigned long flags;
682
683 spin_lock_irqsave(&dev->devres_lock, flags);
684
685 grp = find_group(dev, id);
686 if (grp) {
687 list_del_init(&grp->node[0].entry);
688 list_del_init(&grp->node[1].entry);
689 devres_log(dev, &grp->node[0], "REM");
690 } else
691 WARN_ON(1);
692
693 spin_unlock_irqrestore(&dev->devres_lock, flags);
694
695 kfree(grp);
696}
697EXPORT_SYMBOL_GPL(devres_remove_group);
698
699/**
700 * devres_release_group - Release resources in a devres group
701 * @dev: Device to release group for
702 * @id: ID of target group, can be NULL
703 *
704 * Release all resources in the group identified by @id. If @id is
705 * NULL, the latest open group is selected. The selected group and
706 * groups properly nested inside the selected group are removed.
707 *
708 * RETURNS:
709 * The number of released non-group resources.
710 */
711int devres_release_group(struct device *dev, void *id)
712{
713 struct devres_group *grp;
714 unsigned long flags;
715 LIST_HEAD(todo);
716 int cnt = 0;
717
718 spin_lock_irqsave(&dev->devres_lock, flags);
719 grp = find_group(dev, id);
720 if (grp) {
721 struct list_head *first = &grp->node[0].entry;
722 struct list_head *end = &dev->devres_head;
723
724 if (!list_empty(&grp->node[1].entry))
725 end = grp->node[1].entry.next;
726
727 cnt = remove_nodes(dev, first, end, &todo);
728 } else if (list_empty(&dev->devres_head)) {
729 /*
730 * dev is probably dying via devres_release_all(): groups
731 * have already been removed and are on the process of
732 * being released - don't touch and don't warn.
733 */
734 } else {
735 WARN_ON(1);
736 }
737 spin_unlock_irqrestore(&dev->devres_lock, flags);
738
739 release_nodes(dev, &todo);
740
741 return cnt;
742}
743EXPORT_SYMBOL_GPL(devres_release_group);
744
745/*
746 * Custom devres actions allow inserting a simple function call
747 * into the teardown sequence.
748 */
749
750struct action_devres {
751 void *data;
752 void (*action)(void *);
753};
754
755struct devres_action {
756 struct devres_node node;
757 struct action_devres action;
758};
759
760static int devm_action_match(struct devres_action *devres, struct action_devres *target)
761{
762 return devres->action.action == target->action &&
763 devres->action.data == target->data;
764}
765
766static void devm_action_release(struct device *dev, struct devres_node *node)
767{
768 struct devres_action *devres = container_of(node, struct devres_action, node);
769
770 devres->action.action(devres->action.data);
771}
772
773static void devm_action_free(struct devres_node *node)
774{
775 struct devres_action *action = container_of(node, struct devres_action, node);
776
777 kfree(action);
778}
779
780/**
781 * __devm_add_action() - add a custom action to list of managed resources
782 * @dev: Device that owns the action
783 * @action: Function that should be called
784 * @data: Pointer to data passed to @action implementation
785 * @name: Name of the resource (for debugging purposes)
786 *
787 * This adds a custom action to the list of managed resources so that
788 * it gets executed as part of standard resource unwinding.
789 */
790int __devm_add_action(struct device *dev, void (*action)(void *), void *data, const char *name)
791{
792 struct devres_action *devres;
793
794 devres = kzalloc_obj(*devres);
795 if (!devres)
796 return -ENOMEM;
797
798 devres_node_init(&devres->node, devm_action_release, devm_action_free);
799 devres_set_node_dbginfo(&devres->node, name, sizeof(*devres));
800
801 devres->action.data = data;
802 devres->action.action = action;
803
804 devres_node_add(dev, &devres->node);
805 return 0;
806}
807EXPORT_SYMBOL_GPL(__devm_add_action);
808
809static struct devres_action *devres_action_find(struct device *dev,
810 void (*action)(void *),
811 void *data)
812{
813 struct devres_node *node;
814 struct action_devres target = {
815 .data = data,
816 .action = action,
817 };
818
819 list_for_each_entry_reverse(node, &dev->devres_head, entry) {
820 struct devres_action *dr = container_of(node, struct devres_action, node);
821
822 if (node->release != devm_action_release)
823 continue;
824 if (devm_action_match(dr, &target))
825 return dr;
826 }
827
828 return NULL;
829}
830
831bool devm_is_action_added(struct device *dev, void (*action)(void *), void *data)
832{
833 guard(spinlock_irqsave)(&dev->devres_lock);
834
835 return !!devres_action_find(dev, action, data);
836}
837EXPORT_SYMBOL_GPL(devm_is_action_added);
838
839static struct devres_action *remove_action(struct device *dev,
840 void (*action)(void *),
841 void *data)
842{
843 struct devres_action *dr;
844
845 guard(spinlock_irqsave)(&dev->devres_lock);
846
847 dr = devres_action_find(dev, action, data);
848 if (!dr)
849 return ERR_PTR(-ENOENT);
850
851 list_del_init(&dr->node.entry);
852 devres_log(dev, &dr->node, "REM");
853
854 return dr;
855}
856
857/**
858 * devm_remove_action_nowarn() - removes previously added custom action
859 * @dev: Device that owns the action
860 * @action: Function implementing the action
861 * @data: Pointer to data passed to @action implementation
862 *
863 * Removes instance of @action previously added by devm_add_action().
864 * Both action and data should match one of the existing entries.
865 *
866 * In contrast to devm_remove_action(), this function does not WARN() if no
867 * entry could have been found.
868 *
869 * This should only be used if the action is contained in an object with
870 * independent lifetime management, e.g. the Devres rust abstraction.
871 *
872 * Causing the warning from regular driver code most likely indicates an abuse
873 * of the devres API.
874 *
875 * Returns: 0 on success, -ENOENT if no entry could have been found.
876 */
877int devm_remove_action_nowarn(struct device *dev,
878 void (*action)(void *),
879 void *data)
880{
881 struct devres_action *dr;
882
883 dr = remove_action(dev, action, data);
884 if (IS_ERR(dr))
885 return PTR_ERR(dr);
886
887 kfree(dr);
888
889 return 0;
890}
891EXPORT_SYMBOL_GPL(devm_remove_action_nowarn);
892
893/**
894 * devm_release_action() - release previously added custom action
895 * @dev: Device that owns the action
896 * @action: Function implementing the action
897 * @data: Pointer to data passed to @action implementation
898 *
899 * Releases and removes instance of @action previously added by
900 * devm_add_action(). Both action and data should match one of the
901 * existing entries.
902 */
903void devm_release_action(struct device *dev, void (*action)(void *), void *data)
904{
905 struct devres_action *dr;
906
907 dr = remove_action(dev, action, data);
908 if (WARN_ON(IS_ERR(dr)))
909 return;
910
911 dr->action.action(dr->action.data);
912
913 kfree(dr);
914}
915EXPORT_SYMBOL_GPL(devm_release_action);
916
917/*
918 * Managed kmalloc/kfree
919 */
920static void devm_kmalloc_release(struct device *dev, void *res)
921{
922 /* noop */
923}
924
925static int devm_kmalloc_match(struct device *dev, void *res, void *data)
926{
927 return res == data;
928}
929
930/**
931 * devm_kmalloc - Resource-managed kmalloc
932 * @dev: Device to allocate memory for
933 * @size: Allocation size
934 * @gfp: Allocation gfp flags
935 *
936 * Managed kmalloc. Memory allocated with this function is
937 * automatically freed on driver detach. Like all other devres
938 * resources, guaranteed alignment is unsigned long long.
939 *
940 * RETURNS:
941 * Pointer to allocated memory on success, NULL on failure.
942 */
943void *devm_kmalloc(struct device *dev, size_t size, gfp_t gfp)
944{
945 struct devres *dr;
946
947 if (unlikely(!size))
948 return ZERO_SIZE_PTR;
949
950 /* use raw alloc_dr for kmalloc caller tracing */
951 dr = alloc_dr(devm_kmalloc_release, size, gfp, dev_to_node(dev));
952 if (unlikely(!dr))
953 return NULL;
954
955 /*
956 * This is named devm_kzalloc_release for historical reasons
957 * The initial implementation did not support kmalloc, only kzalloc
958 */
959 devres_set_node_dbginfo(&dr->node, "devm_kzalloc_release", size);
960 devres_add(dev, dr->data);
961 return dr->data;
962}
963EXPORT_SYMBOL_GPL(devm_kmalloc);
964
965/**
966 * devm_krealloc - Resource-managed krealloc()
967 * @dev: Device to re-allocate memory for
968 * @ptr: Pointer to the memory chunk to re-allocate
969 * @new_size: New allocation size
970 * @gfp: Allocation gfp flags
971 *
972 * Managed krealloc(). Resizes the memory chunk allocated with devm_kmalloc().
973 * Behaves similarly to regular krealloc(): if @ptr is NULL or ZERO_SIZE_PTR,
974 * it's the equivalent of devm_kmalloc(). If new_size is zero, it frees the
975 * previously allocated memory and returns ZERO_SIZE_PTR. This function doesn't
976 * change the order in which the release callback for the re-alloc'ed devres
977 * will be called (except when falling back to devm_kmalloc() or when freeing
978 * resources when new_size is zero). The contents of the memory are preserved
979 * up to the lesser of new and old sizes.
980 */
981void *devm_krealloc(struct device *dev, void *ptr, size_t new_size, gfp_t gfp)
982{
983 size_t total_new_size, total_old_size;
984 struct devres *old_dr, *new_dr;
985 unsigned long flags;
986
987 if (unlikely(!new_size)) {
988 devm_kfree(dev, ptr);
989 return ZERO_SIZE_PTR;
990 }
991
992 if (unlikely(ZERO_OR_NULL_PTR(ptr)))
993 return devm_kmalloc(dev, new_size, gfp);
994
995 if (WARN_ON(is_kernel_rodata((unsigned long)ptr)))
996 /*
997 * We cannot reliably realloc a const string returned by
998 * devm_kstrdup_const().
999 */
1000 return NULL;
1001
1002 if (!check_dr_size(new_size, &total_new_size))
1003 return NULL;
1004
1005 total_old_size = ksize(container_of(ptr, struct devres, data));
1006 if (total_old_size == 0) {
1007 WARN(1, "Pointer doesn't point to dynamically allocated memory.");
1008 return NULL;
1009 }
1010
1011 /*
1012 * If new size is smaller or equal to the actual number of bytes
1013 * allocated previously - just return the same pointer.
1014 */
1015 if (total_new_size <= total_old_size)
1016 return ptr;
1017
1018 /*
1019 * Otherwise: allocate new, larger chunk. We need to allocate before
1020 * taking the lock as most probably the caller uses GFP_KERNEL.
1021 * alloc_dr() will call check_dr_size() to reserve extra memory
1022 * for struct devres automatically, so size @new_size user request
1023 * is delivered to it directly as devm_kmalloc() does.
1024 */
1025 new_dr = alloc_dr(devm_kmalloc_release,
1026 new_size, gfp, dev_to_node(dev));
1027 if (!new_dr)
1028 return NULL;
1029
1030 devres_set_node_dbginfo(&new_dr->node, "devm_krealloc_release", new_size);
1031
1032 /*
1033 * The spinlock protects the linked list against concurrent
1034 * modifications but not the resource itself.
1035 */
1036 spin_lock_irqsave(&dev->devres_lock, flags);
1037
1038 old_dr = find_dr(dev, devm_kmalloc_release, devm_kmalloc_match, ptr);
1039 if (!old_dr) {
1040 spin_unlock_irqrestore(&dev->devres_lock, flags);
1041 free_dr(new_dr);
1042 WARN(1, "Memory chunk not managed or managed by a different device.");
1043 return NULL;
1044 }
1045
1046 replace_dr(dev, &old_dr->node, &new_dr->node);
1047
1048 spin_unlock_irqrestore(&dev->devres_lock, flags);
1049
1050 /*
1051 * We can copy the memory contents after releasing the lock as we're
1052 * no longer modifying the list links.
1053 */
1054 memcpy(new_dr->data, old_dr->data,
1055 total_old_size - offsetof(struct devres, data));
1056 /*
1057 * Same for releasing the old devres - it's now been removed from the
1058 * list. This is also the reason why we must not use devm_kfree() - the
1059 * links are no longer valid.
1060 */
1061 free_dr(old_dr);
1062
1063 return new_dr->data;
1064}
1065EXPORT_SYMBOL_GPL(devm_krealloc);
1066
1067/**
1068 * devm_kstrdup - Allocate resource managed space and
1069 * copy an existing string into that.
1070 * @dev: Device to allocate memory for
1071 * @s: the string to duplicate
1072 * @gfp: the GFP mask used in the devm_kmalloc() call when
1073 * allocating memory
1074 * RETURNS:
1075 * Pointer to allocated string on success, NULL on failure.
1076 */
1077char *devm_kstrdup(struct device *dev, const char *s, gfp_t gfp)
1078{
1079 if (!s)
1080 return NULL;
1081
1082 return devm_kmemdup(dev, s, strlen(s) + 1, gfp);
1083}
1084EXPORT_SYMBOL_GPL(devm_kstrdup);
1085
1086/**
1087 * devm_kstrdup_const - resource managed conditional string duplication
1088 * @dev: device for which to duplicate the string
1089 * @s: the string to duplicate
1090 * @gfp: the GFP mask used in the kmalloc() call when allocating memory
1091 *
1092 * Strings allocated by devm_kstrdup_const will be automatically freed when
1093 * the associated device is detached.
1094 *
1095 * RETURNS:
1096 * Source string if it is in .rodata section otherwise it falls back to
1097 * devm_kstrdup.
1098 */
1099const char *devm_kstrdup_const(struct device *dev, const char *s, gfp_t gfp)
1100{
1101 if (is_kernel_rodata((unsigned long)s))
1102 return s;
1103
1104 return devm_kstrdup(dev, s, gfp);
1105}
1106EXPORT_SYMBOL_GPL(devm_kstrdup_const);
1107
1108/**
1109 * devm_kvasprintf - Allocate resource managed space and format a string
1110 * into that.
1111 * @dev: Device to allocate memory for
1112 * @gfp: the GFP mask used in the devm_kmalloc() call when
1113 * allocating memory
1114 * @fmt: The printf()-style format string
1115 * @ap: Arguments for the format string
1116 * RETURNS:
1117 * Pointer to allocated string on success, NULL on failure.
1118 */
1119char *devm_kvasprintf(struct device *dev, gfp_t gfp, const char *fmt,
1120 va_list ap)
1121{
1122 unsigned int len;
1123 char *p;
1124 va_list aq;
1125
1126 va_copy(aq, ap);
1127 len = vsnprintf(NULL, 0, fmt, aq);
1128 va_end(aq);
1129
1130 p = devm_kmalloc(dev, len+1, gfp);
1131 if (!p)
1132 return NULL;
1133
1134 vsnprintf(p, len+1, fmt, ap);
1135
1136 return p;
1137}
1138EXPORT_SYMBOL(devm_kvasprintf);
1139
1140/**
1141 * devm_kasprintf - Allocate resource managed space and format a string
1142 * into that.
1143 * @dev: Device to allocate memory for
1144 * @gfp: the GFP mask used in the devm_kmalloc() call when
1145 * allocating memory
1146 * @fmt: The printf()-style format string
1147 * @...: Arguments for the format string
1148 * RETURNS:
1149 * Pointer to allocated string on success, NULL on failure.
1150 */
1151char *devm_kasprintf(struct device *dev, gfp_t gfp, const char *fmt, ...)
1152{
1153 va_list ap;
1154 char *p;
1155
1156 va_start(ap, fmt);
1157 p = devm_kvasprintf(dev, gfp, fmt, ap);
1158 va_end(ap);
1159
1160 return p;
1161}
1162EXPORT_SYMBOL_GPL(devm_kasprintf);
1163
1164/**
1165 * devm_kfree - Resource-managed kfree
1166 * @dev: Device this memory belongs to
1167 * @p: Memory to free
1168 *
1169 * Free memory allocated with devm_kmalloc().
1170 */
1171void devm_kfree(struct device *dev, const void *p)
1172{
1173 int rc;
1174
1175 /*
1176 * Special cases: pointer to a string in .rodata returned by
1177 * devm_kstrdup_const() or NULL/ZERO ptr.
1178 */
1179 if (unlikely(is_kernel_rodata((unsigned long)p) || ZERO_OR_NULL_PTR(p)))
1180 return;
1181
1182 rc = devres_destroy(dev, devm_kmalloc_release,
1183 devm_kmalloc_match, (void *)p);
1184 WARN_ON(rc);
1185}
1186EXPORT_SYMBOL_GPL(devm_kfree);
1187
1188/**
1189 * devm_kmemdup - Resource-managed kmemdup
1190 * @dev: Device this memory belongs to
1191 * @src: Memory region to duplicate
1192 * @len: Memory region length
1193 * @gfp: GFP mask to use
1194 *
1195 * Duplicate region of a memory using resource managed kmalloc
1196 */
1197void *devm_kmemdup(struct device *dev, const void *src, size_t len, gfp_t gfp)
1198{
1199 void *p;
1200
1201 p = devm_kmalloc(dev, len, gfp);
1202 if (p)
1203 memcpy(p, src, len);
1204
1205 return p;
1206}
1207EXPORT_SYMBOL_GPL(devm_kmemdup);
1208
1209/**
1210 * devm_kmemdup_const - conditionally duplicate and manage a region of memory
1211 *
1212 * @dev: Device this memory belongs to
1213 * @src: memory region to duplicate
1214 * @len: memory region length,
1215 * @gfp: GFP mask to use
1216 *
1217 * Return: source address if it is in .rodata or the return value of kmemdup()
1218 * to which the function falls back otherwise.
1219 */
1220const void *
1221devm_kmemdup_const(struct device *dev, const void *src, size_t len, gfp_t gfp)
1222{
1223 if (is_kernel_rodata((unsigned long)src))
1224 return src;
1225
1226 return devm_kmemdup(dev, src, len, gfp);
1227}
1228EXPORT_SYMBOL_GPL(devm_kmemdup_const);
1229
1230struct pages_devres {
1231 unsigned long addr;
1232 unsigned int order;
1233};
1234
1235static int devm_pages_match(struct device *dev, void *res, void *p)
1236{
1237 struct pages_devres *devres = res;
1238 struct pages_devres *target = p;
1239
1240 return devres->addr == target->addr;
1241}
1242
1243static void devm_pages_release(struct device *dev, void *res)
1244{
1245 struct pages_devres *devres = res;
1246
1247 free_pages(devres->addr, devres->order);
1248}
1249
1250/**
1251 * devm_get_free_pages - Resource-managed __get_free_pages
1252 * @dev: Device to allocate memory for
1253 * @gfp_mask: Allocation gfp flags
1254 * @order: Allocation size is (1 << order) pages
1255 *
1256 * Managed get_free_pages. Memory allocated with this function is
1257 * automatically freed on driver detach.
1258 *
1259 * RETURNS:
1260 * Address of allocated memory on success, 0 on failure.
1261 */
1262
1263unsigned long devm_get_free_pages(struct device *dev,
1264 gfp_t gfp_mask, unsigned int order)
1265{
1266 struct pages_devres *devres;
1267 unsigned long addr;
1268
1269 addr = __get_free_pages(gfp_mask, order);
1270
1271 if (unlikely(!addr))
1272 return 0;
1273
1274 devres = devres_alloc(devm_pages_release,
1275 sizeof(struct pages_devres), GFP_KERNEL);
1276 if (unlikely(!devres)) {
1277 free_pages(addr, order);
1278 return 0;
1279 }
1280
1281 devres->addr = addr;
1282 devres->order = order;
1283
1284 devres_add(dev, devres);
1285 return addr;
1286}
1287EXPORT_SYMBOL_GPL(devm_get_free_pages);
1288
1289/**
1290 * devm_free_pages - Resource-managed free_pages
1291 * @dev: Device this memory belongs to
1292 * @addr: Memory to free
1293 *
1294 * Free memory allocated with devm_get_free_pages(). Unlike free_pages,
1295 * there is no need to supply the @order.
1296 */
1297void devm_free_pages(struct device *dev, unsigned long addr)
1298{
1299 struct pages_devres devres = { .addr = addr };
1300
1301 WARN_ON(devres_release(dev, devm_pages_release, devm_pages_match,
1302 &devres));
1303}
1304EXPORT_SYMBOL_GPL(devm_free_pages);
1305
1306static void devm_percpu_release(struct device *dev, void *pdata)
1307{
1308 void __percpu *p;
1309
1310 p = *(void __percpu **)pdata;
1311 free_percpu(p);
1312}
1313
1314/**
1315 * __devm_alloc_percpu - Resource-managed alloc_percpu
1316 * @dev: Device to allocate per-cpu memory for
1317 * @size: Size of per-cpu memory to allocate
1318 * @align: Alignment of per-cpu memory to allocate
1319 *
1320 * Managed alloc_percpu. Per-cpu memory allocated with this function is
1321 * automatically freed on driver detach.
1322 *
1323 * RETURNS:
1324 * Pointer to allocated memory on success, NULL on failure.
1325 */
1326void __percpu *__devm_alloc_percpu(struct device *dev, size_t size,
1327 size_t align)
1328{
1329 void *p;
1330 void __percpu *pcpu;
1331
1332 pcpu = __alloc_percpu(size, align);
1333 if (!pcpu)
1334 return NULL;
1335
1336 p = devres_alloc(devm_percpu_release, sizeof(void *), GFP_KERNEL);
1337 if (!p) {
1338 free_percpu(pcpu);
1339 return NULL;
1340 }
1341
1342 *(void __percpu **)p = pcpu;
1343
1344 devres_add(dev, p);
1345
1346 return pcpu;
1347}
1348EXPORT_SYMBOL_GPL(__devm_alloc_percpu);