summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/ksysfs.c
blob: c2bedaea11f7b929709e64979e17e15ca4d8d60a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
/*
 * Architecture specific sysfs attributes in /sys/kernel
 *
 * Copyright (C) 2007, Intel Corp.
 *      Huang Ying <ying.huang@intel.com>
 * Copyright (C) 2013, 2013 Red Hat, Inc.
 *      Dave Young <dyoung@redhat.com>
 *
 * This file is released under the GPLv2
 */

#include <linux/kobject.h>
#include <linux/string.h>
#include <linux/sysfs.h>
#include <linux/init.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/mm.h>

#include <asm/io.h>
#include <asm/setup.h>

static ssize_t version_show(struct kobject *kobj,
			    struct kobj_attribute *attr, char *buf)
{
	return sprintf(buf, "0x%04x\n", boot_params.hdr.version);
}

static struct kobj_attribute boot_params_version_attr = __ATTR_RO(version);

static ssize_t boot_params_data_read(struct file *fp, struct kobject *kobj,
				     struct bin_attribute *bin_attr,
				     char *buf, loff_t off, size_t count)
{
	memcpy(buf, (void *)&boot_params + off, count);
	return count;
}

static struct bin_attribute boot_params_data_attr = {
	.attr = {
		.name = "data",
		.mode = S_IRUGO,
	},
	.read = boot_params_data_read,
	.size = sizeof(boot_params),
};

static struct attribute *boot_params_version_attrs[] = {
	&boot_params_version_attr.attr,
	NULL,
};

static struct bin_attribute *boot_params_data_attrs[] = {
	&boot_params_data_attr,
	NULL,
};

static struct attribute_group boot_params_attr_group = {
	.attrs = boot_params_version_attrs,
	.bin_attrs = boot_params_data_attrs,
};

static int kobj_to_setup_data_nr(struct kobject *kobj, int *nr)
{
	const char *name;

	name = kobject_name(kobj);
	return kstrtoint(name, 10, nr);
}

static int get_setup_data_paddr(int nr, u64 *paddr)
{
	int i = 0;
	struct setup_data *data;
	u64 pa_data = boot_params.hdr.setup_data;

	while (pa_data) {
		if (nr == i) {
			*paddr = pa_data;
			return 0;
		}
		data = ioremap_cache(pa_data, sizeof(*data));
		if (!data)
			return -ENOMEM;

		pa_data = data->next;
		iounmap(data);
		i++;
	}
	return -EINVAL;
}

static int __init get_setup_data_size(int nr, size_t *size)
{
	int i = 0;
	struct setup_data *data;
	u64 pa_data = boot_params.hdr.setup_data;

	while (pa_data) {
		data = ioremap_cache(pa_data, sizeof(*data));
		if (!data)
			return -ENOMEM;
		if (nr == i) {
			*size = data->len;
			iounmap(data);
			return 0;
		}

		pa_data = data->next;
		iounmap(data);
		i++;
	}
	return -EINVAL;
}

static ssize_t type_show(struct kobject *kobj,
			 struct kobj_attribute *attr, char *buf)
{
	int nr, ret;
	u64 paddr;
	struct setup_data *data;

	ret = kobj_to_setup_data_nr(kobj, &nr);
	if (ret)
		return ret;

	ret = get_setup_data_paddr(nr, &paddr);
	if (ret)
		return ret;
	data = ioremap_cache(paddr, sizeof(*data));
	if (!data)
		return -ENOMEM;

	ret = sprintf(buf, "0x%x\n", data->type);
	iounmap(data);
	return ret;
}

static ssize_t setup_data_data_read(struct file *fp,
				    struct kobject *kobj,
				    struct bin_attribute *bin_attr,
				    char *buf,
				    loff_t off, size_t count)
{
	int nr, ret = 0;
	u64 paddr;
	struct setup_data *data;
	void *p;

	ret = kobj_to_setup_data_nr(kobj, &nr);
	if (ret)
		return ret;

	ret = get_setup_data_paddr(nr, &paddr);
	if (ret)
		return ret;
	data = ioremap_cache(paddr, sizeof(*data));
	if (!data)
		return -ENOMEM;

	if (off > data->len) {
		ret = -EINVAL;
		goto out;
	}

	if (count > data->len - off)
		count = data->len - off;

	if (!count)
		goto out;

	ret = count;
	p = ioremap_cache(paddr + sizeof(*data), data->len);
	if (!p) {
		ret = -ENOMEM;
		goto out;
	}
	memcpy(buf, p + off, count);
	iounmap(p);
out:
	iounmap(data);
	return ret;
}

static struct kobj_attribute type_attr = __ATTR_RO(type);

static struct bin_attribute data_attr = {
	.attr = {
		.name = "data",
		.mode = S_IRUGO,
	},
	.read = setup_data_data_read,
};

static struct attribute *setup_data_type_attrs[] = {
	&type_attr.attr,
	NULL,
};

static struct bin_attribute *setup_data_data_attrs[] = {
	&data_attr,
	NULL,
};

static struct attribute_group setup_data_attr_group = {
	.attrs = setup_data_type_attrs,
	.bin_attrs = setup_data_data_attrs,
};

static int __init create_setup_data_node(struct kobject *parent,
					 struct kobject **kobjp, int nr)
{
	int ret = 0;
	size_t size;
	struct kobject *kobj;
	char name[16]; /* should be enough for setup_data nodes numbers */
	snprintf(name, 16, "%d", nr);

	kobj = kobject_create_and_add(name, parent);
	if (!kobj)
		return -ENOMEM;

	ret = get_setup_data_size(nr, &size);
	if (ret)
		goto out_kobj;

	data_attr.size = size;
	ret = sysfs_create_group(kobj, &setup_data_attr_group);
	if (ret)
		goto out_kobj;
	*kobjp = kobj;

	return 0;
out_kobj:
	kobject_put(kobj);
	return ret;
}

static void __init cleanup_setup_data_node(struct kobject *kobj)
{
	sysfs_remove_group(kobj, &setup_data_attr_group);
	kobject_put(kobj);
}

static int __init get_setup_data_total_num(u64 pa_data, int *nr)
{
	int ret = 0;
	struct setup_data *data;

	*nr = 0;
	while (pa_data) {
		*nr += 1;
		data = ioremap_cache(pa_data, sizeof(*data));
		if (!data) {
			ret = -ENOMEM;
			goto out;
		}
		pa_data = data->next;
		iounmap(data);
	}

out:
	return ret;
}

static int __init create_setup_data_nodes(struct kobject *parent)
{
	struct kobject *setup_data_kobj, **kobjp;
	u64 pa_data;
	int i, j, nr, ret = 0;

	pa_data = boot_params.hdr.setup_data;
	if (!pa_data)
		return 0;

	setup_data_kobj = kobject_create_and_add("setup_data", parent);
	if (!setup_data_kobj) {
		ret = -ENOMEM;
		goto out;
	}

	ret = get_setup_data_total_num(pa_data, &nr);
	if (ret)
		goto out_setup_data_kobj;

	kobjp = kmalloc(sizeof(*kobjp) * nr, GFP_KERNEL);
	if (!kobjp) {
		ret = -ENOMEM;
		goto out_setup_data_kobj;
	}

	for (i = 0; i < nr; i++) {
		ret = create_setup_data_node(setup_data_kobj, kobjp + i, i);
		if (ret)
			goto out_clean_nodes;
	}

	kfree(kobjp);
	return 0;

out_clean_nodes:
	for (j = i - 1; j > 0; j--)
		cleanup_setup_data_node(*(kobjp + j));
	kfree(kobjp);
out_setup_data_kobj:
	kobject_put(setup_data_kobj);
out:
	return ret;
}

static int __init boot_params_ksysfs_init(void)
{
	int ret;
	struct kobject *boot_params_kobj;

	boot_params_kobj = kobject_create_and_add("boot_params",
						  kernel_kobj);
	if (!boot_params_kobj) {
		ret = -ENOMEM;
		goto out;
	}

	ret = sysfs_create_group(boot_params_kobj, &boot_params_attr_group);
	if (ret)
		goto out_boot_params_kobj;

	ret = create_setup_data_nodes(boot_params_kobj);
	if (ret)
		goto out_create_group;

	return 0;
out_create_group:
	sysfs_remove_group(boot_params_kobj, &boot_params_attr_group);
out_boot_params_kobj:
	kobject_put(boot_params_kobj);
out:
	return ret;
}

arch_initcall(boot_params_ksysfs_init);
OpenPOWER on IntegriCloud