Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * kernel/power/disk.c - Suspend-to-disk support. | |
3 | * | |
4 | * Copyright (c) 2003 Patrick Mochel | |
5 | * Copyright (c) 2003 Open Source Development Lab | |
6 | * Copyright (c) 2004 Pavel Machek <pavel@suse.cz> | |
7 | * | |
8 | * This file is released under the GPLv2. | |
9 | * | |
10 | */ | |
11 | ||
12 | #include <linux/suspend.h> | |
13 | #include <linux/syscalls.h> | |
14 | #include <linux/reboot.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/device.h> | |
17 | #include <linux/delay.h> | |
18 | #include <linux/fs.h> | |
d53d9f16 | 19 | #include <linux/mount.h> |
88d10bba | 20 | #include <linux/pm.h> |
d53d9f16 | 21 | |
1da177e4 LT |
22 | #include "power.h" |
23 | ||
24 | ||
1da177e4 LT |
25 | static int noresume = 0; |
26 | char resume_file[256] = CONFIG_PM_STD_PARTITION; | |
27 | dev_t swsusp_resume_device; | |
28 | ||
29 | /** | |
30 | * power_down - Shut machine down for hibernate. | |
31 | * @mode: Suspend-to-disk mode | |
32 | * | |
33 | * Use the platform driver, if configured so, and return gracefully if it | |
34 | * fails. | |
35 | * Otherwise, try to power off and reboot. If they fail, halt the machine, | |
36 | * there ain't no turning back. | |
37 | */ | |
38 | ||
39 | static void power_down(suspend_disk_method_t mode) | |
40 | { | |
1da177e4 LT |
41 | int error = 0; |
42 | ||
1da177e4 LT |
43 | switch(mode) { |
44 | case PM_DISK_PLATFORM: | |
729b4d4c | 45 | kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK); |
1da177e4 LT |
46 | error = pm_ops->enter(PM_SUSPEND_DISK); |
47 | break; | |
48 | case PM_DISK_SHUTDOWN: | |
fdde86ac | 49 | kernel_power_off(); |
1da177e4 LT |
50 | break; |
51 | case PM_DISK_REBOOT: | |
fdde86ac | 52 | kernel_restart(NULL); |
1da177e4 LT |
53 | break; |
54 | } | |
fdde86ac | 55 | kernel_halt(); |
1da177e4 LT |
56 | /* Valid image is on the disk, if we continue we risk serious data corruption |
57 | after resume. */ | |
58 | printk(KERN_CRIT "Please power me down manually\n"); | |
59 | while(1); | |
60 | } | |
61 | ||
1da177e4 LT |
62 | static inline void platform_finish(void) |
63 | { | |
64 | if (pm_disk_mode == PM_DISK_PLATFORM) { | |
65 | if (pm_ops && pm_ops->finish) | |
66 | pm_ops->finish(PM_SUSPEND_DISK); | |
67 | } | |
68 | } | |
69 | ||
1da177e4 LT |
70 | static int prepare_processes(void) |
71 | { | |
72 | int error; | |
73 | ||
74 | pm_prepare_console(); | |
5a72e04d LS |
75 | disable_nonboot_cpus(); |
76 | ||
1da177e4 LT |
77 | if (freeze_processes()) { |
78 | error = -EBUSY; | |
5a72e04d | 79 | goto thaw; |
1da177e4 LT |
80 | } |
81 | ||
1da177e4 | 82 | /* Free memory before shutting down devices. */ |
72a97e08 RW |
83 | if (!(error = swsusp_shrink_memory())) |
84 | return 0; | |
5a72e04d LS |
85 | thaw: |
86 | thaw_processes(); | |
87 | enable_nonboot_cpus(); | |
88 | pm_restore_console(); | |
89 | return error; | |
1da177e4 LT |
90 | } |
91 | ||
92 | static void unprepare_processes(void) | |
93 | { | |
5a72e04d | 94 | platform_finish(); |
1da177e4 | 95 | thaw_processes(); |
5a72e04d | 96 | enable_nonboot_cpus(); |
1da177e4 LT |
97 | pm_restore_console(); |
98 | } | |
99 | ||
1da177e4 LT |
100 | /** |
101 | * pm_suspend_disk - The granpappy of power management. | |
102 | * | |
103 | * If we're going through the firmware, then get it over with quickly. | |
104 | * | |
105 | * If not, then call swsusp to do its thing, then figure out how | |
106 | * to power down the system. | |
107 | */ | |
108 | ||
109 | int pm_suspend_disk(void) | |
110 | { | |
111 | int error; | |
112 | ||
113 | error = prepare_processes(); | |
5a72e04d LS |
114 | if (error) |
115 | return error; | |
1da177e4 | 116 | |
99dc7d63 | 117 | error = device_suspend(PMSG_FREEZE); |
1da177e4 | 118 | if (error) { |
99dc7d63 | 119 | printk("Some devices failed to suspend\n"); |
1da177e4 LT |
120 | unprepare_processes(); |
121 | return error; | |
122 | } | |
123 | ||
1da177e4 LT |
124 | pr_debug("PM: snapshotting memory.\n"); |
125 | in_suspend = 1; | |
126 | if ((error = swsusp_suspend())) | |
127 | goto Done; | |
128 | ||
129 | if (in_suspend) { | |
0245b3e7 | 130 | device_resume(); |
1da177e4 | 131 | pr_debug("PM: writing image.\n"); |
f577eb30 | 132 | error = swsusp_write(); |
1da177e4 LT |
133 | if (!error) |
134 | power_down(pm_disk_mode); | |
99dc7d63 | 135 | else { |
99dc7d63 PM |
136 | swsusp_free(); |
137 | unprepare_processes(); | |
138 | return error; | |
139 | } | |
1da177e4 LT |
140 | } else |
141 | pr_debug("PM: Image restored successfully.\n"); | |
99dc7d63 | 142 | |
1da177e4 LT |
143 | swsusp_free(); |
144 | Done: | |
99dc7d63 PM |
145 | device_resume(); |
146 | unprepare_processes(); | |
1da177e4 LT |
147 | return error; |
148 | } | |
149 | ||
150 | ||
151 | /** | |
152 | * software_resume - Resume from a saved image. | |
153 | * | |
154 | * Called as a late_initcall (so all devices are discovered and | |
155 | * initialized), we call swsusp to see if we have a saved image or not. | |
156 | * If so, we quiesce devices, the restore the saved image. We will | |
157 | * return above (in pm_suspend_disk() ) if everything goes well. | |
158 | * Otherwise, we fail gracefully and return to the normally | |
159 | * scheduled program. | |
160 | * | |
161 | */ | |
162 | ||
163 | static int software_resume(void) | |
164 | { | |
165 | int error; | |
166 | ||
dd5d666b | 167 | down(&pm_sem); |
3efa147a | 168 | if (!swsusp_resume_device) { |
dd5d666b SL |
169 | if (!strlen(resume_file)) { |
170 | up(&pm_sem); | |
3efa147a | 171 | return -ENOENT; |
dd5d666b | 172 | } |
3efa147a PM |
173 | swsusp_resume_device = name_to_dev_t(resume_file); |
174 | pr_debug("swsusp: Resume From Partition %s\n", resume_file); | |
175 | } else { | |
176 | pr_debug("swsusp: Resume From Partition %d:%d\n", | |
177 | MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); | |
178 | } | |
179 | ||
1da177e4 LT |
180 | if (noresume) { |
181 | /** | |
182 | * FIXME: If noresume is specified, we need to find the partition | |
183 | * and reset it back to normal swap space. | |
184 | */ | |
dd5d666b | 185 | up(&pm_sem); |
1da177e4 LT |
186 | return 0; |
187 | } | |
188 | ||
189 | pr_debug("PM: Checking swsusp image.\n"); | |
190 | ||
191 | if ((error = swsusp_check())) | |
192 | goto Done; | |
193 | ||
194 | pr_debug("PM: Preparing processes for restore.\n"); | |
195 | ||
196 | if ((error = prepare_processes())) { | |
197 | swsusp_close(); | |
5a72e04d | 198 | goto Done; |
1da177e4 LT |
199 | } |
200 | ||
201 | pr_debug("PM: Reading swsusp image.\n"); | |
202 | ||
f577eb30 | 203 | if ((error = swsusp_read())) { |
2c1b4a5c RW |
204 | swsusp_free(); |
205 | goto Thaw; | |
206 | } | |
1da177e4 LT |
207 | |
208 | pr_debug("PM: Preparing devices for restore.\n"); | |
209 | ||
99dc7d63 PM |
210 | if ((error = device_suspend(PMSG_FREEZE))) { |
211 | printk("Some devices failed to suspend\n"); | |
2c1b4a5c RW |
212 | swsusp_free(); |
213 | goto Thaw; | |
99dc7d63 | 214 | } |
1da177e4 LT |
215 | |
216 | mb(); | |
217 | ||
218 | pr_debug("PM: Restoring saved image.\n"); | |
219 | swsusp_resume(); | |
220 | pr_debug("PM: Restore failed, recovering.n"); | |
99dc7d63 | 221 | device_resume(); |
2c1b4a5c | 222 | Thaw: |
1da177e4 LT |
223 | unprepare_processes(); |
224 | Done: | |
dd5d666b SL |
225 | /* For success case, the suspend path will release the lock */ |
226 | up(&pm_sem); | |
1da177e4 LT |
227 | pr_debug("PM: Resume from disk failed.\n"); |
228 | return 0; | |
229 | } | |
230 | ||
231 | late_initcall(software_resume); | |
232 | ||
233 | ||
3b364b8d | 234 | static const char * const pm_disk_modes[] = { |
1da177e4 LT |
235 | [PM_DISK_FIRMWARE] = "firmware", |
236 | [PM_DISK_PLATFORM] = "platform", | |
237 | [PM_DISK_SHUTDOWN] = "shutdown", | |
238 | [PM_DISK_REBOOT] = "reboot", | |
239 | }; | |
240 | ||
241 | /** | |
242 | * disk - Control suspend-to-disk mode | |
243 | * | |
244 | * Suspend-to-disk can be handled in several ways. The greatest | |
245 | * distinction is who writes memory to disk - the firmware or the OS. | |
246 | * If the firmware does it, we assume that it also handles suspending | |
247 | * the system. | |
248 | * If the OS does it, then we have three options for putting the system | |
249 | * to sleep - using the platform driver (e.g. ACPI or other PM registers), | |
250 | * powering off the system or rebooting the system (for testing). | |
251 | * | |
252 | * The system will support either 'firmware' or 'platform', and that is | |
253 | * known a priori (and encoded in pm_ops). But, the user may choose | |
254 | * 'shutdown' or 'reboot' as alternatives. | |
255 | * | |
256 | * show() will display what the mode is currently set to. | |
257 | * store() will accept one of | |
258 | * | |
259 | * 'firmware' | |
260 | * 'platform' | |
261 | * 'shutdown' | |
262 | * 'reboot' | |
263 | * | |
264 | * It will only change to 'firmware' or 'platform' if the system | |
265 | * supports it (as determined from pm_ops->pm_disk_mode). | |
266 | */ | |
267 | ||
268 | static ssize_t disk_show(struct subsystem * subsys, char * buf) | |
269 | { | |
270 | return sprintf(buf, "%s\n", pm_disk_modes[pm_disk_mode]); | |
271 | } | |
272 | ||
273 | ||
274 | static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n) | |
275 | { | |
276 | int error = 0; | |
277 | int i; | |
278 | int len; | |
279 | char *p; | |
280 | suspend_disk_method_t mode = 0; | |
281 | ||
282 | p = memchr(buf, '\n', n); | |
283 | len = p ? p - buf : n; | |
284 | ||
285 | down(&pm_sem); | |
286 | for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) { | |
287 | if (!strncmp(buf, pm_disk_modes[i], len)) { | |
288 | mode = i; | |
289 | break; | |
290 | } | |
291 | } | |
292 | if (mode) { | |
293 | if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT) | |
294 | pm_disk_mode = mode; | |
295 | else { | |
296 | if (pm_ops && pm_ops->enter && | |
297 | (mode == pm_ops->pm_disk_mode)) | |
298 | pm_disk_mode = mode; | |
299 | else | |
300 | error = -EINVAL; | |
301 | } | |
302 | } else | |
303 | error = -EINVAL; | |
304 | ||
305 | pr_debug("PM: suspend-to-disk mode set to '%s'\n", | |
306 | pm_disk_modes[mode]); | |
307 | up(&pm_sem); | |
308 | return error ? error : n; | |
309 | } | |
310 | ||
311 | power_attr(disk); | |
312 | ||
313 | static ssize_t resume_show(struct subsystem * subsys, char *buf) | |
314 | { | |
315 | return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device), | |
316 | MINOR(swsusp_resume_device)); | |
317 | } | |
318 | ||
a576219a | 319 | static ssize_t resume_store(struct subsystem *subsys, const char *buf, size_t n) |
1da177e4 | 320 | { |
1da177e4 | 321 | unsigned int maj, min; |
1da177e4 | 322 | dev_t res; |
a576219a | 323 | int ret = -EINVAL; |
1da177e4 | 324 | |
a576219a AM |
325 | if (sscanf(buf, "%u:%u", &maj, &min) != 2) |
326 | goto out; | |
1da177e4 | 327 | |
a576219a AM |
328 | res = MKDEV(maj,min); |
329 | if (maj != MAJOR(res) || min != MINOR(res)) | |
330 | goto out; | |
1da177e4 | 331 | |
a576219a AM |
332 | down(&pm_sem); |
333 | swsusp_resume_device = res; | |
334 | up(&pm_sem); | |
335 | printk("Attempting manual resume\n"); | |
336 | noresume = 0; | |
337 | software_resume(); | |
338 | ret = n; | |
339 | out: | |
340 | return ret; | |
1da177e4 LT |
341 | } |
342 | ||
343 | power_attr(resume); | |
344 | ||
ca0aec0f RW |
345 | static ssize_t image_size_show(struct subsystem * subsys, char *buf) |
346 | { | |
853609b6 | 347 | return sprintf(buf, "%lu\n", image_size); |
ca0aec0f RW |
348 | } |
349 | ||
350 | static ssize_t image_size_store(struct subsystem * subsys, const char * buf, size_t n) | |
351 | { | |
853609b6 | 352 | unsigned long size; |
ca0aec0f | 353 | |
853609b6 | 354 | if (sscanf(buf, "%lu", &size) == 1) { |
ca0aec0f RW |
355 | image_size = size; |
356 | return n; | |
357 | } | |
358 | ||
359 | return -EINVAL; | |
360 | } | |
361 | ||
362 | power_attr(image_size); | |
363 | ||
1da177e4 LT |
364 | static struct attribute * g[] = { |
365 | &disk_attr.attr, | |
366 | &resume_attr.attr, | |
ca0aec0f | 367 | &image_size_attr.attr, |
1da177e4 LT |
368 | NULL, |
369 | }; | |
370 | ||
371 | ||
372 | static struct attribute_group attr_group = { | |
373 | .attrs = g, | |
374 | }; | |
375 | ||
376 | ||
377 | static int __init pm_disk_init(void) | |
378 | { | |
379 | return sysfs_create_group(&power_subsys.kset.kobj,&attr_group); | |
380 | } | |
381 | ||
382 | core_initcall(pm_disk_init); | |
383 | ||
384 | ||
385 | static int __init resume_setup(char *str) | |
386 | { | |
387 | if (noresume) | |
388 | return 1; | |
389 | ||
390 | strncpy( resume_file, str, 255 ); | |
391 | return 1; | |
392 | } | |
393 | ||
394 | static int __init noresume_setup(char *str) | |
395 | { | |
396 | noresume = 1; | |
397 | return 1; | |
398 | } | |
399 | ||
400 | __setup("noresume", noresume_setup); | |
401 | __setup("resume=", resume_setup); |