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13#include <linux/sysfs.h>
14#include <linux/ctype.h>
15#include <linux/device.h>
16#include <linux/slab.h>
17#include <linux/uuid.h>
18#include <linux/mdev.h>
19
20#include "mdev_private.h"
21
22
23
24static ssize_t mdev_type_attr_show(struct kobject *kobj,
25 struct attribute *__attr, char *buf)
26{
27 struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
28 struct mdev_type *type = to_mdev_type(kobj);
29 ssize_t ret = -EIO;
30
31 if (attr->show)
32 ret = attr->show(kobj, type->parent->dev, buf);
33 return ret;
34}
35
36static ssize_t mdev_type_attr_store(struct kobject *kobj,
37 struct attribute *__attr,
38 const char *buf, size_t count)
39{
40 struct mdev_type_attribute *attr = to_mdev_type_attr(__attr);
41 struct mdev_type *type = to_mdev_type(kobj);
42 ssize_t ret = -EIO;
43
44 if (attr->store)
45 ret = attr->store(&type->kobj, type->parent->dev, buf, count);
46 return ret;
47}
48
49static const struct sysfs_ops mdev_type_sysfs_ops = {
50 .show = mdev_type_attr_show,
51 .store = mdev_type_attr_store,
52};
53
54static ssize_t create_store(struct kobject *kobj, struct device *dev,
55 const char *buf, size_t count)
56{
57 char *str;
58 uuid_le uuid;
59 int ret;
60
61 if ((count < UUID_STRING_LEN) || (count > UUID_STRING_LEN + 1))
62 return -EINVAL;
63
64 str = kstrndup(buf, count, GFP_KERNEL);
65 if (!str)
66 return -ENOMEM;
67
68 ret = uuid_le_to_bin(str, &uuid);
69 kfree(str);
70 if (ret)
71 return ret;
72
73 ret = mdev_device_create(kobj, dev, uuid);
74 if (ret)
75 return ret;
76
77 return count;
78}
79
80MDEV_TYPE_ATTR_WO(create);
81
82static void mdev_type_release(struct kobject *kobj)
83{
84 struct mdev_type *type = to_mdev_type(kobj);
85
86 pr_debug("Releasing group %s\n", kobj->name);
87 kfree(type);
88}
89
90static struct kobj_type mdev_type_ktype = {
91 .sysfs_ops = &mdev_type_sysfs_ops,
92 .release = mdev_type_release,
93};
94
95struct mdev_type *add_mdev_supported_type(struct mdev_parent *parent,
96 struct attribute_group *group)
97{
98 struct mdev_type *type;
99 int ret;
100
101 if (!group->name) {
102 pr_err("%s: Type name empty!\n", __func__);
103 return ERR_PTR(-EINVAL);
104 }
105
106 type = kzalloc(sizeof(*type), GFP_KERNEL);
107 if (!type)
108 return ERR_PTR(-ENOMEM);
109
110 type->kobj.kset = parent->mdev_types_kset;
111
112 ret = kobject_init_and_add(&type->kobj, &mdev_type_ktype, NULL,
113 "%s-%s", dev_driver_string(parent->dev),
114 group->name);
115 if (ret) {
116 kfree(type);
117 return ERR_PTR(ret);
118 }
119
120 ret = sysfs_create_file(&type->kobj, &mdev_type_attr_create.attr);
121 if (ret)
122 goto attr_create_failed;
123
124 type->devices_kobj = kobject_create_and_add("devices", &type->kobj);
125 if (!type->devices_kobj) {
126 ret = -ENOMEM;
127 goto attr_devices_failed;
128 }
129
130 ret = sysfs_create_files(&type->kobj,
131 (const struct attribute **)group->attrs);
132 if (ret) {
133 ret = -ENOMEM;
134 goto attrs_failed;
135 }
136
137 type->group = group;
138 type->parent = parent;
139 return type;
140
141attrs_failed:
142 kobject_put(type->devices_kobj);
143attr_devices_failed:
144 sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
145attr_create_failed:
146 kobject_del(&type->kobj);
147 kobject_put(&type->kobj);
148 return ERR_PTR(ret);
149}
150
151static void remove_mdev_supported_type(struct mdev_type *type)
152{
153 sysfs_remove_files(&type->kobj,
154 (const struct attribute **)type->group->attrs);
155 kobject_put(type->devices_kobj);
156 sysfs_remove_file(&type->kobj, &mdev_type_attr_create.attr);
157 kobject_del(&type->kobj);
158 kobject_put(&type->kobj);
159}
160
161static int add_mdev_supported_type_groups(struct mdev_parent *parent)
162{
163 int i;
164
165 for (i = 0; parent->ops->supported_type_groups[i]; i++) {
166 struct mdev_type *type;
167
168 type = add_mdev_supported_type(parent,
169 parent->ops->supported_type_groups[i]);
170 if (IS_ERR(type)) {
171 struct mdev_type *ltype, *tmp;
172
173 list_for_each_entry_safe(ltype, tmp, &parent->type_list,
174 next) {
175 list_del(<ype->next);
176 remove_mdev_supported_type(ltype);
177 }
178 return PTR_ERR(type);
179 }
180 list_add(&type->next, &parent->type_list);
181 }
182 return 0;
183}
184
185
186void parent_remove_sysfs_files(struct mdev_parent *parent)
187{
188 struct mdev_type *type, *tmp;
189
190 list_for_each_entry_safe(type, tmp, &parent->type_list, next) {
191 list_del(&type->next);
192 remove_mdev_supported_type(type);
193 }
194
195 sysfs_remove_groups(&parent->dev->kobj, parent->ops->dev_attr_groups);
196 kset_unregister(parent->mdev_types_kset);
197}
198
199int parent_create_sysfs_files(struct mdev_parent *parent)
200{
201 int ret;
202
203 parent->mdev_types_kset = kset_create_and_add("mdev_supported_types",
204 NULL, &parent->dev->kobj);
205
206 if (!parent->mdev_types_kset)
207 return -ENOMEM;
208
209 INIT_LIST_HEAD(&parent->type_list);
210
211 ret = sysfs_create_groups(&parent->dev->kobj,
212 parent->ops->dev_attr_groups);
213 if (ret)
214 goto create_err;
215
216 ret = add_mdev_supported_type_groups(parent);
217 if (ret)
218 sysfs_remove_groups(&parent->dev->kobj,
219 parent->ops->dev_attr_groups);
220 else
221 return ret;
222
223create_err:
224 kset_unregister(parent->mdev_types_kset);
225 return ret;
226}
227
228static void remove_callback(struct device *dev)
229{
230 int ret;
231
232 ret = mdev_device_remove(dev, false);
233 if (ret)
234 dev_info(dev, "Unable to remove device: %d\n",ret);
235}
236
237static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
238 const char *buf, size_t count)
239{
240 unsigned long val;
241
242 if (kstrtoul(buf, 0, &val) < 0)
243 return -EINVAL;
244
245 if (val) {
246 int ret = device_schedule_callback(dev, remove_callback);
247
248 if (ret)
249 count = ret;
250 }
251
252 return count;
253}
254
255static DEVICE_ATTR_WO(remove);
256
257static const struct attribute *mdev_device_attrs[] = {
258 &dev_attr_remove.attr,
259 NULL,
260};
261
262int mdev_create_sysfs_files(struct device *dev, struct mdev_type *type)
263{
264 int ret;
265
266 ret = sysfs_create_files(&dev->kobj, mdev_device_attrs);
267 if (ret)
268 return ret;
269
270 ret = sysfs_create_link(type->devices_kobj, &dev->kobj, dev_name(dev));
271 if (ret)
272 goto device_link_failed;
273
274 ret = sysfs_create_link(&dev->kobj, &type->kobj, "mdev_type");
275 if (ret)
276 goto type_link_failed;
277
278 return ret;
279
280type_link_failed:
281 sysfs_remove_link(type->devices_kobj, dev_name(dev));
282device_link_failed:
283 sysfs_remove_files(&dev->kobj, mdev_device_attrs);
284 return ret;
285}
286
287void mdev_remove_sysfs_files(struct device *dev, struct mdev_type *type)
288{
289 sysfs_remove_link(&dev->kobj, "mdev_type");
290 sysfs_remove_link(type->devices_kobj, dev_name(dev));
291 sysfs_remove_files(&dev->kobj, mdev_device_attrs);
292}
293
