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> |
e3920fb4 | 21 | #include <linux/cpu.h> |
d53d9f16 | 22 | |
1da177e4 LT |
23 | #include "power.h" |
24 | ||
25 | ||
1da177e4 LT |
26 | static int noresume = 0; |
27 | char resume_file[256] = CONFIG_PM_STD_PARTITION; | |
28 | dev_t swsusp_resume_device; | |
29 | ||
30 | /** | |
31 | * power_down - Shut machine down for hibernate. | |
32 | * @mode: Suspend-to-disk mode | |
33 | * | |
34 | * Use the platform driver, if configured so, and return gracefully if it | |
35 | * fails. | |
36 | * Otherwise, try to power off and reboot. If they fail, halt the machine, | |
37 | * there ain't no turning back. | |
38 | */ | |
39 | ||
40 | static void power_down(suspend_disk_method_t mode) | |
41 | { | |
1da177e4 LT |
42 | int error = 0; |
43 | ||
1da177e4 LT |
44 | switch(mode) { |
45 | case PM_DISK_PLATFORM: | |
729b4d4c | 46 | kernel_shutdown_prepare(SYSTEM_SUSPEND_DISK); |
1da177e4 LT |
47 | error = pm_ops->enter(PM_SUSPEND_DISK); |
48 | break; | |
49 | case PM_DISK_SHUTDOWN: | |
fdde86ac | 50 | kernel_power_off(); |
1da177e4 LT |
51 | break; |
52 | case PM_DISK_REBOOT: | |
fdde86ac | 53 | kernel_restart(NULL); |
1da177e4 LT |
54 | break; |
55 | } | |
fdde86ac | 56 | kernel_halt(); |
1da177e4 LT |
57 | /* Valid image is on the disk, if we continue we risk serious data corruption |
58 | after resume. */ | |
59 | printk(KERN_CRIT "Please power me down manually\n"); | |
60 | while(1); | |
61 | } | |
62 | ||
1da177e4 LT |
63 | static inline void platform_finish(void) |
64 | { | |
65 | if (pm_disk_mode == PM_DISK_PLATFORM) { | |
66 | if (pm_ops && pm_ops->finish) | |
67 | pm_ops->finish(PM_SUSPEND_DISK); | |
68 | } | |
69 | } | |
70 | ||
1da177e4 LT |
71 | static int prepare_processes(void) |
72 | { | |
73 | int error; | |
74 | ||
75 | pm_prepare_console(); | |
e3920fb4 RW |
76 | |
77 | error = disable_nonboot_cpus(); | |
78 | if (error) | |
79 | goto enable_cpus; | |
5a72e04d | 80 | |
1da177e4 LT |
81 | if (freeze_processes()) { |
82 | error = -EBUSY; | |
5a72e04d | 83 | goto thaw; |
1da177e4 LT |
84 | } |
85 | ||
1da177e4 | 86 | /* Free memory before shutting down devices. */ |
72a97e08 RW |
87 | if (!(error = swsusp_shrink_memory())) |
88 | return 0; | |
5a72e04d LS |
89 | thaw: |
90 | thaw_processes(); | |
e3920fb4 | 91 | enable_cpus: |
5a72e04d LS |
92 | enable_nonboot_cpus(); |
93 | pm_restore_console(); | |
94 | return error; | |
1da177e4 LT |
95 | } |
96 | ||
97 | static void unprepare_processes(void) | |
98 | { | |
5a72e04d | 99 | platform_finish(); |
1da177e4 | 100 | thaw_processes(); |
5a72e04d | 101 | enable_nonboot_cpus(); |
1da177e4 LT |
102 | pm_restore_console(); |
103 | } | |
104 | ||
1da177e4 | 105 | /** |
f1cc0a89 | 106 | * pm_suspend_disk - The granpappy of hibernation power management. |
1da177e4 LT |
107 | * |
108 | * If we're going through the firmware, then get it over with quickly. | |
109 | * | |
110 | * If not, then call swsusp to do its thing, then figure out how | |
111 | * to power down the system. | |
112 | */ | |
113 | ||
114 | int pm_suspend_disk(void) | |
115 | { | |
116 | int error; | |
117 | ||
118 | error = prepare_processes(); | |
5a72e04d LS |
119 | if (error) |
120 | return error; | |
1da177e4 | 121 | |
99dc7d63 | 122 | error = device_suspend(PMSG_FREEZE); |
1da177e4 | 123 | if (error) { |
99dc7d63 | 124 | printk("Some devices failed to suspend\n"); |
1da177e4 LT |
125 | unprepare_processes(); |
126 | return error; | |
127 | } | |
128 | ||
1da177e4 LT |
129 | pr_debug("PM: snapshotting memory.\n"); |
130 | in_suspend = 1; | |
131 | if ((error = swsusp_suspend())) | |
132 | goto Done; | |
133 | ||
134 | if (in_suspend) { | |
0245b3e7 | 135 | device_resume(); |
1da177e4 | 136 | pr_debug("PM: writing image.\n"); |
f577eb30 | 137 | error = swsusp_write(); |
1da177e4 LT |
138 | if (!error) |
139 | power_down(pm_disk_mode); | |
99dc7d63 | 140 | else { |
99dc7d63 PM |
141 | swsusp_free(); |
142 | unprepare_processes(); | |
143 | return error; | |
144 | } | |
1da177e4 LT |
145 | } else |
146 | pr_debug("PM: Image restored successfully.\n"); | |
99dc7d63 | 147 | |
1da177e4 LT |
148 | swsusp_free(); |
149 | Done: | |
99dc7d63 PM |
150 | device_resume(); |
151 | unprepare_processes(); | |
1da177e4 LT |
152 | return error; |
153 | } | |
154 | ||
155 | ||
156 | /** | |
157 | * software_resume - Resume from a saved image. | |
158 | * | |
159 | * Called as a late_initcall (so all devices are discovered and | |
160 | * initialized), we call swsusp to see if we have a saved image or not. | |
161 | * If so, we quiesce devices, the restore the saved image. We will | |
162 | * return above (in pm_suspend_disk() ) if everything goes well. | |
163 | * Otherwise, we fail gracefully and return to the normally | |
164 | * scheduled program. | |
165 | * | |
166 | */ | |
167 | ||
168 | static int software_resume(void) | |
169 | { | |
170 | int error; | |
171 | ||
dd5d666b | 172 | down(&pm_sem); |
3efa147a | 173 | if (!swsusp_resume_device) { |
dd5d666b SL |
174 | if (!strlen(resume_file)) { |
175 | up(&pm_sem); | |
3efa147a | 176 | return -ENOENT; |
dd5d666b | 177 | } |
3efa147a PM |
178 | swsusp_resume_device = name_to_dev_t(resume_file); |
179 | pr_debug("swsusp: Resume From Partition %s\n", resume_file); | |
180 | } else { | |
181 | pr_debug("swsusp: Resume From Partition %d:%d\n", | |
182 | MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); | |
183 | } | |
184 | ||
1da177e4 LT |
185 | if (noresume) { |
186 | /** | |
187 | * FIXME: If noresume is specified, we need to find the partition | |
188 | * and reset it back to normal swap space. | |
189 | */ | |
dd5d666b | 190 | up(&pm_sem); |
1da177e4 LT |
191 | return 0; |
192 | } | |
193 | ||
194 | pr_debug("PM: Checking swsusp image.\n"); | |
195 | ||
196 | if ((error = swsusp_check())) | |
197 | goto Done; | |
198 | ||
199 | pr_debug("PM: Preparing processes for restore.\n"); | |
200 | ||
201 | if ((error = prepare_processes())) { | |
202 | swsusp_close(); | |
5a72e04d | 203 | goto Done; |
1da177e4 LT |
204 | } |
205 | ||
206 | pr_debug("PM: Reading swsusp image.\n"); | |
207 | ||
f577eb30 | 208 | if ((error = swsusp_read())) { |
2c1b4a5c RW |
209 | swsusp_free(); |
210 | goto Thaw; | |
211 | } | |
1da177e4 LT |
212 | |
213 | pr_debug("PM: Preparing devices for restore.\n"); | |
214 | ||
f1cc0a89 | 215 | if ((error = device_suspend(PMSG_PRETHAW))) { |
99dc7d63 | 216 | printk("Some devices failed to suspend\n"); |
2c1b4a5c RW |
217 | swsusp_free(); |
218 | goto Thaw; | |
99dc7d63 | 219 | } |
1da177e4 LT |
220 | |
221 | mb(); | |
222 | ||
223 | pr_debug("PM: Restoring saved image.\n"); | |
224 | swsusp_resume(); | |
225 | pr_debug("PM: Restore failed, recovering.n"); | |
99dc7d63 | 226 | device_resume(); |
2c1b4a5c | 227 | Thaw: |
1da177e4 LT |
228 | unprepare_processes(); |
229 | Done: | |
dd5d666b SL |
230 | /* For success case, the suspend path will release the lock */ |
231 | up(&pm_sem); | |
1da177e4 LT |
232 | pr_debug("PM: Resume from disk failed.\n"); |
233 | return 0; | |
234 | } | |
235 | ||
236 | late_initcall(software_resume); | |
237 | ||
238 | ||
3b364b8d | 239 | static const char * const pm_disk_modes[] = { |
1da177e4 LT |
240 | [PM_DISK_FIRMWARE] = "firmware", |
241 | [PM_DISK_PLATFORM] = "platform", | |
242 | [PM_DISK_SHUTDOWN] = "shutdown", | |
243 | [PM_DISK_REBOOT] = "reboot", | |
244 | }; | |
245 | ||
246 | /** | |
247 | * disk - Control suspend-to-disk mode | |
248 | * | |
249 | * Suspend-to-disk can be handled in several ways. The greatest | |
250 | * distinction is who writes memory to disk - the firmware or the OS. | |
251 | * If the firmware does it, we assume that it also handles suspending | |
252 | * the system. | |
253 | * If the OS does it, then we have three options for putting the system | |
254 | * to sleep - using the platform driver (e.g. ACPI or other PM registers), | |
255 | * powering off the system or rebooting the system (for testing). | |
256 | * | |
257 | * The system will support either 'firmware' or 'platform', and that is | |
258 | * known a priori (and encoded in pm_ops). But, the user may choose | |
259 | * 'shutdown' or 'reboot' as alternatives. | |
260 | * | |
261 | * show() will display what the mode is currently set to. | |
262 | * store() will accept one of | |
263 | * | |
264 | * 'firmware' | |
265 | * 'platform' | |
266 | * 'shutdown' | |
267 | * 'reboot' | |
268 | * | |
269 | * It will only change to 'firmware' or 'platform' if the system | |
270 | * supports it (as determined from pm_ops->pm_disk_mode). | |
271 | */ | |
272 | ||
273 | static ssize_t disk_show(struct subsystem * subsys, char * buf) | |
274 | { | |
275 | return sprintf(buf, "%s\n", pm_disk_modes[pm_disk_mode]); | |
276 | } | |
277 | ||
278 | ||
279 | static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n) | |
280 | { | |
281 | int error = 0; | |
282 | int i; | |
283 | int len; | |
284 | char *p; | |
285 | suspend_disk_method_t mode = 0; | |
286 | ||
287 | p = memchr(buf, '\n', n); | |
288 | len = p ? p - buf : n; | |
289 | ||
290 | down(&pm_sem); | |
291 | for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) { | |
292 | if (!strncmp(buf, pm_disk_modes[i], len)) { | |
293 | mode = i; | |
294 | break; | |
295 | } | |
296 | } | |
297 | if (mode) { | |
298 | if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT) | |
299 | pm_disk_mode = mode; | |
300 | else { | |
301 | if (pm_ops && pm_ops->enter && | |
302 | (mode == pm_ops->pm_disk_mode)) | |
303 | pm_disk_mode = mode; | |
304 | else | |
305 | error = -EINVAL; | |
306 | } | |
307 | } else | |
308 | error = -EINVAL; | |
309 | ||
310 | pr_debug("PM: suspend-to-disk mode set to '%s'\n", | |
311 | pm_disk_modes[mode]); | |
312 | up(&pm_sem); | |
313 | return error ? error : n; | |
314 | } | |
315 | ||
316 | power_attr(disk); | |
317 | ||
318 | static ssize_t resume_show(struct subsystem * subsys, char *buf) | |
319 | { | |
320 | return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device), | |
321 | MINOR(swsusp_resume_device)); | |
322 | } | |
323 | ||
a576219a | 324 | static ssize_t resume_store(struct subsystem *subsys, const char *buf, size_t n) |
1da177e4 | 325 | { |
1da177e4 | 326 | unsigned int maj, min; |
1da177e4 | 327 | dev_t res; |
a576219a | 328 | int ret = -EINVAL; |
1da177e4 | 329 | |
a576219a AM |
330 | if (sscanf(buf, "%u:%u", &maj, &min) != 2) |
331 | goto out; | |
1da177e4 | 332 | |
a576219a AM |
333 | res = MKDEV(maj,min); |
334 | if (maj != MAJOR(res) || min != MINOR(res)) | |
335 | goto out; | |
1da177e4 | 336 | |
a576219a AM |
337 | down(&pm_sem); |
338 | swsusp_resume_device = res; | |
339 | up(&pm_sem); | |
340 | printk("Attempting manual resume\n"); | |
341 | noresume = 0; | |
342 | software_resume(); | |
343 | ret = n; | |
344 | out: | |
345 | return ret; | |
1da177e4 LT |
346 | } |
347 | ||
348 | power_attr(resume); | |
349 | ||
ca0aec0f RW |
350 | static ssize_t image_size_show(struct subsystem * subsys, char *buf) |
351 | { | |
853609b6 | 352 | return sprintf(buf, "%lu\n", image_size); |
ca0aec0f RW |
353 | } |
354 | ||
355 | static ssize_t image_size_store(struct subsystem * subsys, const char * buf, size_t n) | |
356 | { | |
853609b6 | 357 | unsigned long size; |
ca0aec0f | 358 | |
853609b6 | 359 | if (sscanf(buf, "%lu", &size) == 1) { |
ca0aec0f RW |
360 | image_size = size; |
361 | return n; | |
362 | } | |
363 | ||
364 | return -EINVAL; | |
365 | } | |
366 | ||
367 | power_attr(image_size); | |
368 | ||
1da177e4 LT |
369 | static struct attribute * g[] = { |
370 | &disk_attr.attr, | |
371 | &resume_attr.attr, | |
ca0aec0f | 372 | &image_size_attr.attr, |
1da177e4 LT |
373 | NULL, |
374 | }; | |
375 | ||
376 | ||
377 | static struct attribute_group attr_group = { | |
378 | .attrs = g, | |
379 | }; | |
380 | ||
381 | ||
382 | static int __init pm_disk_init(void) | |
383 | { | |
384 | return sysfs_create_group(&power_subsys.kset.kobj,&attr_group); | |
385 | } | |
386 | ||
387 | core_initcall(pm_disk_init); | |
388 | ||
389 | ||
390 | static int __init resume_setup(char *str) | |
391 | { | |
392 | if (noresume) | |
393 | return 1; | |
394 | ||
395 | strncpy( resume_file, str, 255 ); | |
396 | return 1; | |
397 | } | |
398 | ||
399 | static int __init noresume_setup(char *str) | |
400 | { | |
401 | noresume = 1; | |
402 | return 1; | |
403 | } | |
404 | ||
405 | __setup("noresume", noresume_setup); | |
406 | __setup("resume=", resume_setup); |