2 * drivers/base/devres.c - device resource management
4 * Copyright (c) 2006 SUSE Linux Products GmbH
5 * Copyright (c) 2006 Tejun Heo <teheo@suse.de>
7 * This file is released under the GPLv2.
10 #include <linux/device.h>
11 #include <linux/module.h>
12 #include <linux/slab.h>
17 struct list_head entry
;
19 #ifdef CONFIG_DEBUG_DEVRES
26 struct devres_node node
;
28 unsigned long long data
[]; /* guarantee ull alignment */
32 struct devres_node node
[2];
38 #ifdef CONFIG_DEBUG_DEVRES
39 static int log_devres
= 0;
40 module_param_named(log
, log_devres
, int, S_IRUGO
| S_IWUSR
);
42 static void set_node_dbginfo(struct devres_node
*node
, const char *name
,
49 static void devres_log(struct device
*dev
, struct devres_node
*node
,
52 if (unlikely(log_devres
))
53 dev_printk(KERN_ERR
, dev
, "DEVRES %3s %p %s (%lu bytes)\n",
54 op
, node
, node
->name
, (unsigned long)node
->size
);
56 #else /* CONFIG_DEBUG_DEVRES */
57 #define set_node_dbginfo(node, n, s) do {} while (0)
58 #define devres_log(dev, node, op) do {} while (0)
59 #endif /* CONFIG_DEBUG_DEVRES */
62 * Release functions for devres group. These callbacks are used only
65 static void group_open_release(struct device
*dev
, void *res
)
70 static void group_close_release(struct device
*dev
, void *res
)
75 static struct devres_group
* node_to_group(struct devres_node
*node
)
77 if (node
->release
== &group_open_release
)
78 return container_of(node
, struct devres_group
, node
[0]);
79 if (node
->release
== &group_close_release
)
80 return container_of(node
, struct devres_group
, node
[1]);
84 static __always_inline
struct devres
* alloc_dr(dr_release_t release
,
85 size_t size
, gfp_t gfp
)
87 size_t tot_size
= sizeof(struct devres
) + size
;
90 dr
= kmalloc_track_caller(tot_size
, gfp
);
94 memset(dr
, 0, tot_size
);
95 INIT_LIST_HEAD(&dr
->node
.entry
);
96 dr
->node
.release
= release
;
100 static void add_dr(struct device
*dev
, struct devres_node
*node
)
102 devres_log(dev
, node
, "ADD");
103 BUG_ON(!list_empty(&node
->entry
));
104 list_add_tail(&node
->entry
, &dev
->devres_head
);
107 #ifdef CONFIG_DEBUG_DEVRES
108 void * __devres_alloc(dr_release_t release
, size_t size
, gfp_t gfp
,
113 dr
= alloc_dr(release
, size
, gfp
);
116 set_node_dbginfo(&dr
->node
, name
, size
);
119 EXPORT_SYMBOL_GPL(__devres_alloc
);
122 * devres_alloc - Allocate device resource data
123 * @release: Release function devres will be associated with
124 * @size: Allocation size
125 * @gfp: Allocation flags
127 * Allocate devres of @size bytes. The allocated area is zeroed, then
128 * associated with @release. The returned pointer can be passed to
129 * other devres_*() functions.
132 * Pointer to allocated devres on success, NULL on failure.
134 void * devres_alloc(dr_release_t release
, size_t size
, gfp_t gfp
)
138 dr
= alloc_dr(release
, size
, gfp
);
143 EXPORT_SYMBOL_GPL(devres_alloc
);
147 * devres_free - Free device resource data
148 * @res: Pointer to devres data to free
150 * Free devres created with devres_alloc().
152 void devres_free(void *res
)
155 struct devres
*dr
= container_of(res
, struct devres
, data
);
157 BUG_ON(!list_empty(&dr
->node
.entry
));
161 EXPORT_SYMBOL_GPL(devres_free
);
164 * devres_add - Register device resource
165 * @dev: Device to add resource to
166 * @res: Resource to register
168 * Register devres @res to @dev. @res should have been allocated
169 * using devres_alloc(). On driver detach, the associated release
170 * function will be invoked and devres will be freed automatically.
172 void devres_add(struct device
*dev
, void *res
)
174 struct devres
*dr
= container_of(res
, struct devres
, data
);
177 spin_lock_irqsave(&dev
->devres_lock
, flags
);
178 add_dr(dev
, &dr
->node
);
179 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
181 EXPORT_SYMBOL_GPL(devres_add
);
183 static struct devres
*find_dr(struct device
*dev
, dr_release_t release
,
184 dr_match_t match
, void *match_data
)
186 struct devres_node
*node
;
188 list_for_each_entry_reverse(node
, &dev
->devres_head
, entry
) {
189 struct devres
*dr
= container_of(node
, struct devres
, node
);
191 if (node
->release
!= release
)
193 if (match
&& !match(dev
, dr
->data
, match_data
))
202 * devres_find - Find device resource
203 * @dev: Device to lookup resource from
204 * @release: Look for resources associated with this release function
205 * @match: Match function (optional)
206 * @match_data: Data for the match function
208 * Find the latest devres of @dev which is associated with @release
209 * and for which @match returns 1. If @match is NULL, it's considered
213 * Pointer to found devres, NULL if not found.
215 void * devres_find(struct device
*dev
, dr_release_t release
,
216 dr_match_t match
, void *match_data
)
221 spin_lock_irqsave(&dev
->devres_lock
, flags
);
222 dr
= find_dr(dev
, release
, match
, match_data
);
223 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
229 EXPORT_SYMBOL_GPL(devres_find
);
232 * devres_get - Find devres, if non-existent, add one atomically
233 * @dev: Device to lookup or add devres for
234 * @new_res: Pointer to new initialized devres to add if not found
235 * @match: Match function (optional)
236 * @match_data: Data for the match function
238 * Find the latest devres of @dev which has the same release function
239 * as @new_res and for which @match return 1. If found, @new_res is
240 * freed; otherwise, @new_res is added atomically.
243 * Pointer to found or added devres.
245 void * devres_get(struct device
*dev
, void *new_res
,
246 dr_match_t match
, void *match_data
)
248 struct devres
*new_dr
= container_of(new_res
, struct devres
, data
);
252 spin_lock_irqsave(&dev
->devres_lock
, flags
);
253 dr
= find_dr(dev
, new_dr
->node
.release
, match
, match_data
);
255 add_dr(dev
, &new_dr
->node
);
259 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
264 EXPORT_SYMBOL_GPL(devres_get
);
267 * devres_remove - Find a device resource and remove it
268 * @dev: Device to find resource from
269 * @release: Look for resources associated with this release function
270 * @match: Match function (optional)
271 * @match_data: Data for the match function
273 * Find the latest devres of @dev associated with @release and for
274 * which @match returns 1. If @match is NULL, it's considered to
275 * match all. If found, the resource is removed atomically and
279 * Pointer to removed devres on success, NULL if not found.
281 void * devres_remove(struct device
*dev
, dr_release_t release
,
282 dr_match_t match
, void *match_data
)
287 spin_lock_irqsave(&dev
->devres_lock
, flags
);
288 dr
= find_dr(dev
, release
, match
, match_data
);
290 list_del_init(&dr
->node
.entry
);
291 devres_log(dev
, &dr
->node
, "REM");
293 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
299 EXPORT_SYMBOL_GPL(devres_remove
);
302 * devres_destroy - Find a device resource and destroy it
303 * @dev: Device to find resource from
304 * @release: Look for resources associated with this release function
305 * @match: Match function (optional)
306 * @match_data: Data for the match function
308 * Find the latest devres of @dev associated with @release and for
309 * which @match returns 1. If @match is NULL, it's considered to
310 * match all. If found, the resource is removed atomically and freed.
312 * Note that the release function for the resource will not be called,
313 * only the devres-allocated data will be freed. The caller becomes
314 * responsible for freeing any other data.
317 * 0 if devres is found and freed, -ENOENT if not found.
319 int devres_destroy(struct device
*dev
, dr_release_t release
,
320 dr_match_t match
, void *match_data
)
324 res
= devres_remove(dev
, release
, match
, match_data
);
331 EXPORT_SYMBOL_GPL(devres_destroy
);
335 * devres_release - Find a device resource and destroy it, calling release
336 * @dev: Device to find resource from
337 * @release: Look for resources associated with this release function
338 * @match: Match function (optional)
339 * @match_data: Data for the match function
341 * Find the latest devres of @dev associated with @release and for
342 * which @match returns 1. If @match is NULL, it's considered to
343 * match all. If found, the resource is removed atomically, the
344 * release function called and the resource freed.
347 * 0 if devres is found and freed, -ENOENT if not found.
349 int devres_release(struct device
*dev
, dr_release_t release
,
350 dr_match_t match
, void *match_data
)
354 res
= devres_remove(dev
, release
, match
, match_data
);
358 (*release
)(dev
, res
);
362 EXPORT_SYMBOL_GPL(devres_release
);
364 static int remove_nodes(struct device
*dev
,
365 struct list_head
*first
, struct list_head
*end
,
366 struct list_head
*todo
)
368 int cnt
= 0, nr_groups
= 0;
369 struct list_head
*cur
;
371 /* First pass - move normal devres entries to @todo and clear
372 * devres_group colors.
376 struct devres_node
*node
;
377 struct devres_group
*grp
;
379 node
= list_entry(cur
, struct devres_node
, entry
);
382 grp
= node_to_group(node
);
384 /* clear color of group markers in the first pass */
388 /* regular devres entry */
389 if (&node
->entry
== first
)
391 list_move_tail(&node
->entry
, todo
);
399 /* Second pass - Scan groups and color them. A group gets
400 * color value of two iff the group is wholly contained in
401 * [cur, end). That is, for a closed group, both opening and
402 * closing markers should be in the range, while just the
403 * opening marker is enough for an open group.
407 struct devres_node
*node
;
408 struct devres_group
*grp
;
410 node
= list_entry(cur
, struct devres_node
, entry
);
413 grp
= node_to_group(node
);
414 BUG_ON(!grp
|| list_empty(&grp
->node
[0].entry
));
417 if (list_empty(&grp
->node
[1].entry
))
420 BUG_ON(grp
->color
<= 0 || grp
->color
> 2);
421 if (grp
->color
== 2) {
422 /* No need to update cur or end. The removed
423 * nodes are always before both.
425 list_move_tail(&grp
->node
[0].entry
, todo
);
426 list_del_init(&grp
->node
[1].entry
);
433 static int release_nodes(struct device
*dev
, struct list_head
*first
,
434 struct list_head
*end
, unsigned long flags
)
435 __releases(&dev
->devres_lock
)
439 struct devres
*dr
, *tmp
;
441 cnt
= remove_nodes(dev
, first
, end
, &todo
);
443 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
445 /* Release. Note that both devres and devres_group are
446 * handled as devres in the following loop. This is safe.
448 list_for_each_entry_safe_reverse(dr
, tmp
, &todo
, node
.entry
) {
449 devres_log(dev
, &dr
->node
, "REL");
450 dr
->node
.release(dev
, dr
->data
);
458 * devres_release_all - Release all managed resources
459 * @dev: Device to release resources for
461 * Release all resources associated with @dev. This function is
462 * called on driver detach.
464 int devres_release_all(struct device
*dev
)
468 /* Looks like an uninitialized device structure */
469 if (WARN_ON(dev
->devres_head
.next
== NULL
))
471 spin_lock_irqsave(&dev
->devres_lock
, flags
);
472 return release_nodes(dev
, dev
->devres_head
.next
, &dev
->devres_head
,
477 * devres_open_group - Open a new devres group
478 * @dev: Device to open devres group for
480 * @gfp: Allocation flags
482 * Open a new devres group for @dev with @id. For @id, using a
483 * pointer to an object which won't be used for another group is
484 * recommended. If @id is NULL, address-wise unique ID is created.
487 * ID of the new group, NULL on failure.
489 void * devres_open_group(struct device
*dev
, void *id
, gfp_t gfp
)
491 struct devres_group
*grp
;
494 grp
= kmalloc(sizeof(*grp
), gfp
);
498 grp
->node
[0].release
= &group_open_release
;
499 grp
->node
[1].release
= &group_close_release
;
500 INIT_LIST_HEAD(&grp
->node
[0].entry
);
501 INIT_LIST_HEAD(&grp
->node
[1].entry
);
502 set_node_dbginfo(&grp
->node
[0], "grp<", 0);
503 set_node_dbginfo(&grp
->node
[1], "grp>", 0);
508 spin_lock_irqsave(&dev
->devres_lock
, flags
);
509 add_dr(dev
, &grp
->node
[0]);
510 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
513 EXPORT_SYMBOL_GPL(devres_open_group
);
515 /* Find devres group with ID @id. If @id is NULL, look for the latest. */
516 static struct devres_group
* find_group(struct device
*dev
, void *id
)
518 struct devres_node
*node
;
520 list_for_each_entry_reverse(node
, &dev
->devres_head
, entry
) {
521 struct devres_group
*grp
;
523 if (node
->release
!= &group_open_release
)
526 grp
= container_of(node
, struct devres_group
, node
[0]);
531 } else if (list_empty(&grp
->node
[1].entry
))
539 * devres_close_group - Close a devres group
540 * @dev: Device to close devres group for
541 * @id: ID of target group, can be NULL
543 * Close the group identified by @id. If @id is NULL, the latest open
546 void devres_close_group(struct device
*dev
, void *id
)
548 struct devres_group
*grp
;
551 spin_lock_irqsave(&dev
->devres_lock
, flags
);
553 grp
= find_group(dev
, id
);
555 add_dr(dev
, &grp
->node
[1]);
559 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
561 EXPORT_SYMBOL_GPL(devres_close_group
);
564 * devres_remove_group - Remove a devres group
565 * @dev: Device to remove group for
566 * @id: ID of target group, can be NULL
568 * Remove the group identified by @id. If @id is NULL, the latest
569 * open group is selected. Note that removing a group doesn't affect
570 * any other resources.
572 void devres_remove_group(struct device
*dev
, void *id
)
574 struct devres_group
*grp
;
577 spin_lock_irqsave(&dev
->devres_lock
, flags
);
579 grp
= find_group(dev
, id
);
581 list_del_init(&grp
->node
[0].entry
);
582 list_del_init(&grp
->node
[1].entry
);
583 devres_log(dev
, &grp
->node
[0], "REM");
587 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
591 EXPORT_SYMBOL_GPL(devres_remove_group
);
594 * devres_release_group - Release resources in a devres group
595 * @dev: Device to release group for
596 * @id: ID of target group, can be NULL
598 * Release all resources in the group identified by @id. If @id is
599 * NULL, the latest open group is selected. The selected group and
600 * groups properly nested inside the selected group are removed.
603 * The number of released non-group resources.
605 int devres_release_group(struct device
*dev
, void *id
)
607 struct devres_group
*grp
;
611 spin_lock_irqsave(&dev
->devres_lock
, flags
);
613 grp
= find_group(dev
, id
);
615 struct list_head
*first
= &grp
->node
[0].entry
;
616 struct list_head
*end
= &dev
->devres_head
;
618 if (!list_empty(&grp
->node
[1].entry
))
619 end
= grp
->node
[1].entry
.next
;
621 cnt
= release_nodes(dev
, first
, end
, flags
);
624 spin_unlock_irqrestore(&dev
->devres_lock
, flags
);
629 EXPORT_SYMBOL_GPL(devres_release_group
);
632 * Managed kzalloc/kfree
634 static void devm_kzalloc_release(struct device
*dev
, void *res
)
639 static int devm_kzalloc_match(struct device
*dev
, void *res
, void *data
)
645 * devm_kzalloc - Resource-managed kzalloc
646 * @dev: Device to allocate memory for
647 * @size: Allocation size
648 * @gfp: Allocation gfp flags
650 * Managed kzalloc. Memory allocated with this function is
651 * automatically freed on driver detach. Like all other devres
652 * resources, guaranteed alignment is unsigned long long.
655 * Pointer to allocated memory on success, NULL on failure.
657 void * devm_kzalloc(struct device
*dev
, size_t size
, gfp_t gfp
)
661 /* use raw alloc_dr for kmalloc caller tracing */
662 dr
= alloc_dr(devm_kzalloc_release
, size
, gfp
);
666 set_node_dbginfo(&dr
->node
, "devm_kzalloc_release", size
);
667 devres_add(dev
, dr
->data
);
670 EXPORT_SYMBOL_GPL(devm_kzalloc
);
673 * devm_kfree - Resource-managed kfree
674 * @dev: Device this memory belongs to
677 * Free memory allocated with devm_kzalloc().
679 void devm_kfree(struct device
*dev
, void *p
)
683 rc
= devres_destroy(dev
, devm_kzalloc_release
, devm_kzalloc_match
, p
);
686 EXPORT_SYMBOL_GPL(devm_kfree
);
This page took 0.044325 seconds and 5 git commands to generate.