summaryrefslogtreecommitdiff
path: root/kernel/power/tuxonice_sysfs.c
blob: 77f36dbeb1494cb512c614a0a4683a12e0ae090c (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
/*
 * kernel/power/tuxonice_sysfs.c
 *
 * Copyright (C) 2002-2015 Nigel Cunningham (nigel at nigelcunningham com au)
 *
 * This file is released under the GPLv2.
 *
 * This file contains support for sysfs entries for tuning TuxOnIce.
 *
 * We have a generic handler that deals with the most common cases, and
 * hooks for special handlers to use.
 */

#include <linux/suspend.h>

#include "tuxonice_sysfs.h"
#include "tuxonice.h"
#include "tuxonice_storage.h"
#include "tuxonice_alloc.h"

static int toi_sysfs_initialised;

static void toi_initialise_sysfs(void);

static struct toi_sysfs_data sysfs_params[];

#define to_sysfs_data(_attr) container_of(_attr, struct toi_sysfs_data, attr)

static void toi_main_wrapper(void)
{
        toi_try_hibernate();
}

static ssize_t toi_attr_show(struct kobject *kobj, struct attribute *attr,
                              char *page)
{
        struct toi_sysfs_data *sysfs_data = to_sysfs_data(attr);
        int len = 0;
        int full_prep = sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ;

        if (full_prep && toi_start_anything(0))
                return -EBUSY;

        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ)
                toi_prepare_usm();

        switch (sysfs_data->type) {
        case TOI_SYSFS_DATA_CUSTOM:
                len = (sysfs_data->data.special.read_sysfs) ?
                        (sysfs_data->data.special.read_sysfs)(page, PAGE_SIZE)
                        : 0;
                break;
        case TOI_SYSFS_DATA_BIT:
                len = sprintf(page, "%d\n",
                        -test_bit(sysfs_data->data.bit.bit,
                                sysfs_data->data.bit.bit_vector));
                break;
        case TOI_SYSFS_DATA_INTEGER:
                len = sprintf(page, "%d\n",
                        *(sysfs_data->data.integer.variable));
                break;
        case TOI_SYSFS_DATA_LONG:
                len = sprintf(page, "%ld\n",
                        *(sysfs_data->data.a_long.variable));
                break;
        case TOI_SYSFS_DATA_UL:
                len = sprintf(page, "%lu\n",
                        *(sysfs_data->data.ul.variable));
                break;
        case TOI_SYSFS_DATA_STRING:
                len = sprintf(page, "%s\n",
                        sysfs_data->data.string.variable);
                break;
        }

        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_READ)
                toi_cleanup_usm();

        if (full_prep)
                toi_finish_anything(0);

        return len;
}

#define BOUND(_variable, _type) do { \
        if (*_variable < sysfs_data->data._type.minimum) \
                *_variable = sysfs_data->data._type.minimum; \
        else if (*_variable > sysfs_data->data._type.maximum) \
                *_variable = sysfs_data->data._type.maximum; \
} while (0)

static ssize_t toi_attr_store(struct kobject *kobj, struct attribute *attr,
                const char *my_buf, size_t count)
{
        int assigned_temp_buffer = 0, result = count;
        struct toi_sysfs_data *sysfs_data = to_sysfs_data(attr);

        if (toi_start_anything((sysfs_data->flags & SYSFS_HIBERNATE_OR_RESUME)))
                return -EBUSY;

        ((char *) my_buf)[count] = 0;

        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_WRITE)
                toi_prepare_usm();

        switch (sysfs_data->type) {
        case TOI_SYSFS_DATA_CUSTOM:
                if (sysfs_data->data.special.write_sysfs)
                        result = (sysfs_data->data.special.write_sysfs)(my_buf,
                                        count);
                break;
        case TOI_SYSFS_DATA_BIT:
                {
                unsigned long value;
                result = kstrtoul(my_buf, 0, &value);
                if (result)
                        break;
                if (value)
                        set_bit(sysfs_data->data.bit.bit,
                                (sysfs_data->data.bit.bit_vector));
                else
                        clear_bit(sysfs_data->data.bit.bit,
                                (sysfs_data->data.bit.bit_vector));
                }
                break;
        case TOI_SYSFS_DATA_INTEGER:
                {
                        long temp;
                        result = kstrtol(my_buf, 0, &temp);
                        if (result)
                                break;
                        *(sysfs_data->data.integer.variable) = (int) temp;
                        BOUND(sysfs_data->data.integer.variable, integer);
                        break;
                }
        case TOI_SYSFS_DATA_LONG:
                {
                        long *variable =
                                sysfs_data->data.a_long.variable;
                        result = kstrtol(my_buf, 0, variable);
                        if (result)
                                break;
                        BOUND(variable, a_long);
                        break;
                }
        case TOI_SYSFS_DATA_UL:
                {
                        unsigned long *variable =
                                sysfs_data->data.ul.variable;
                        result = kstrtoul(my_buf, 0, variable);
                        if (result)
                                break;
                        BOUND(variable, ul);
                        break;
                }
                break;
        case TOI_SYSFS_DATA_STRING:
                {
                        int copy_len = count;
                        char *variable =
                                sysfs_data->data.string.variable;

                        if (sysfs_data->data.string.max_length &&
                            (copy_len > sysfs_data->data.string.max_length))
                                copy_len = sysfs_data->data.string.max_length;

                        if (!variable) {
                                variable = (char *) toi_get_zeroed_page(31,
                                                TOI_ATOMIC_GFP);
                                sysfs_data->data.string.variable = variable;
                                assigned_temp_buffer = 1;
                        }
                        strncpy(variable, my_buf, copy_len);
                        if (copy_len && my_buf[copy_len - 1] == '\n')
                                variable[count - 1] = 0;
                        variable[count] = 0;
                }
                break;
        }

        if (!result)
                result = count;

        /* Side effect routine? */
        if (result == count && sysfs_data->write_side_effect)
                sysfs_data->write_side_effect();

        /* Free temporary buffers */
        if (assigned_temp_buffer) {
                toi_free_page(31,
                        (unsigned long) sysfs_data->data.string.variable);
                sysfs_data->data.string.variable = NULL;
        }

        if (sysfs_data->flags & SYSFS_NEEDS_SM_FOR_WRITE)
                toi_cleanup_usm();

        toi_finish_anything(sysfs_data->flags & SYSFS_HIBERNATE_OR_RESUME);

        return result;
}

static struct sysfs_ops toi_sysfs_ops = {
        .show        = &toi_attr_show,
        .store        = &toi_attr_store,
};

static struct kobj_type toi_ktype = {
        .sysfs_ops        = &toi_sysfs_ops,
};

struct kobject *tuxonice_kobj;

/* Non-module sysfs entries.
 *
 * This array contains entries that are automatically registered at
 * boot. Modules and the console code register their own entries separately.
 */

static struct toi_sysfs_data sysfs_params[] = {
        SYSFS_CUSTOM("do_hibernate", SYSFS_WRITEONLY, NULL, NULL,
                SYSFS_HIBERNATING, toi_main_wrapper),
        SYSFS_CUSTOM("do_resume", SYSFS_WRITEONLY, NULL, NULL,
                SYSFS_RESUMING, toi_try_resume)
};

void remove_toi_sysdir(struct kobject *kobj)
{
        if (!kobj)
                return;

        kobject_put(kobj);
}

struct kobject *make_toi_sysdir(char *name)
{
        struct kobject *kobj = kobject_create_and_add(name, tuxonice_kobj);

        if (!kobj) {
                printk(KERN_INFO "TuxOnIce: Can't allocate kobject for sysfs "
                                "dir!\n");
                return NULL;
        }

        kobj->ktype = &toi_ktype;

        return kobj;
}

/* toi_register_sysfs_file
 *
 * Helper for registering a new /sysfs/tuxonice entry.
 */

int toi_register_sysfs_file(
                struct kobject *kobj,
                struct toi_sysfs_data *toi_sysfs_data)
{
        int result;

        if (!toi_sysfs_initialised)
                toi_initialise_sysfs();

        result = sysfs_create_file(kobj, &toi_sysfs_data->attr);
        if (result)
                printk(KERN_INFO "TuxOnIce: sysfs_create_file for %s "
                        "returned %d.\n",
                        toi_sysfs_data->attr.name, result);
        kobj->ktype = &toi_ktype;

        return result;
}

/* toi_unregister_sysfs_file
 *
 * Helper for removing unwanted /sys/power/tuxonice entries.
 *
 */
void toi_unregister_sysfs_file(struct kobject *kobj,
                struct toi_sysfs_data *toi_sysfs_data)
{
        sysfs_remove_file(kobj, &toi_sysfs_data->attr);
}

void toi_cleanup_sysfs(void)
{
        int i,
            numfiles = sizeof(sysfs_params) / sizeof(struct toi_sysfs_data);

        if (!toi_sysfs_initialised)
                return;

        for (i = 0; i < numfiles; i++)
                toi_unregister_sysfs_file(tuxonice_kobj, &sysfs_params[i]);

        kobject_put(tuxonice_kobj);
        toi_sysfs_initialised = 0;
}

/* toi_initialise_sysfs
 *
 * Initialise the /sysfs/tuxonice directory.
 */

static void toi_initialise_sysfs(void)
{
        int i;
        int numfiles = sizeof(sysfs_params) / sizeof(struct toi_sysfs_data);

        if (toi_sysfs_initialised)
                return;

        /* Make our TuxOnIce directory a child of /sys/power */
        tuxonice_kobj = kobject_create_and_add("tuxonice", power_kobj);
        if (!tuxonice_kobj)
                return;

        toi_sysfs_initialised = 1;

        for (i = 0; i < numfiles; i++)
                toi_register_sysfs_file(tuxonice_kobj, &sysfs_params[i]);
}

int toi_sysfs_init(void)
{
        toi_initialise_sysfs();
        return 0;
}

void toi_sysfs_exit(void)
{
        toi_cleanup_sysfs();
}