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16#include <linux/string.h>
17#include <linux/module.h>
18#include <linux/stat.h>
19#include <linux/slab.h>
20
21#include <linux/configfs.h>
22
23
24static inline struct config_item *to_item(struct list_head *entry)
25{
26 return container_of(entry, struct config_item, ci_entry);
27}
28
29
30static void config_item_release(struct kref *kref);
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35
36static void config_item_init(struct config_item *item)
37{
38 kref_init(&item->ci_kref);
39 INIT_LIST_HEAD(&item->ci_entry);
40}
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50
51int config_item_set_name(struct config_item *item, const char *fmt, ...)
52{
53 int limit = CONFIGFS_ITEM_NAME_LEN;
54 int need;
55 va_list args;
56 char *name;
57
58
59
60
61 va_start(args, fmt);
62 need = vsnprintf(item->ci_namebuf, limit, fmt, args);
63 va_end(args);
64 if (need < limit)
65 name = item->ci_namebuf;
66 else {
67 va_start(args, fmt);
68 name = kvasprintf(GFP_KERNEL, fmt, args);
69 va_end(args);
70 if (!name)
71 return -EFAULT;
72 }
73
74
75 if (item->ci_name && item->ci_name != item->ci_namebuf)
76 kfree(item->ci_name);
77
78
79 item->ci_name = name;
80 return 0;
81}
82EXPORT_SYMBOL(config_item_set_name);
83
84void config_item_init_type_name(struct config_item *item,
85 const char *name,
86 const struct config_item_type *type)
87{
88 config_item_set_name(item, "%s", name);
89 item->ci_type = type;
90 config_item_init(item);
91}
92EXPORT_SYMBOL(config_item_init_type_name);
93
94void config_group_init_type_name(struct config_group *group, const char *name,
95 const struct config_item_type *type)
96{
97 config_item_set_name(&group->cg_item, "%s", name);
98 group->cg_item.ci_type = type;
99 config_group_init(group);
100}
101EXPORT_SYMBOL(config_group_init_type_name);
102
103struct config_item *config_item_get(struct config_item *item)
104{
105 if (item)
106 kref_get(&item->ci_kref);
107 return item;
108}
109EXPORT_SYMBOL(config_item_get);
110
111struct config_item *config_item_get_unless_zero(struct config_item *item)
112{
113 if (item && kref_get_unless_zero(&item->ci_kref))
114 return item;
115 return NULL;
116}
117EXPORT_SYMBOL(config_item_get_unless_zero);
118
119static void config_item_cleanup(struct config_item *item)
120{
121 const struct config_item_type *t = item->ci_type;
122 struct config_group *s = item->ci_group;
123 struct config_item *parent = item->ci_parent;
124
125 pr_debug("config_item %s: cleaning up\n", config_item_name(item));
126 if (item->ci_name != item->ci_namebuf)
127 kfree(item->ci_name);
128 item->ci_name = NULL;
129 if (t && t->ct_item_ops && t->ct_item_ops->release)
130 t->ct_item_ops->release(item);
131 if (s)
132 config_group_put(s);
133 if (parent)
134 config_item_put(parent);
135}
136
137static void config_item_release(struct kref *kref)
138{
139 config_item_cleanup(container_of(kref, struct config_item, ci_kref));
140}
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148void config_item_put(struct config_item *item)
149{
150 if (item)
151 kref_put(&item->ci_kref, config_item_release);
152}
153EXPORT_SYMBOL(config_item_put);
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158
159void config_group_init(struct config_group *group)
160{
161 config_item_init(&group->cg_item);
162 INIT_LIST_HEAD(&group->cg_children);
163 INIT_LIST_HEAD(&group->default_groups);
164}
165EXPORT_SYMBOL(config_group_init);
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176struct config_item *config_group_find_item(struct config_group *group,
177 const char *name)
178{
179 struct list_head *entry;
180 struct config_item *ret = NULL;
181
182 list_for_each(entry, &group->cg_children) {
183 struct config_item *item = to_item(entry);
184 if (config_item_name(item) &&
185 !strcmp(config_item_name(item), name)) {
186 ret = config_item_get(item);
187 break;
188 }
189 }
190 return ret;
191}
192EXPORT_SYMBOL(config_group_find_item);
193