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/kmod.h>
18 #include <linux/delay.h>
19 #include <linux/fs.h>
20 #include <linux/mount.h>
21 #include <linux/pm.h>
22 #include <linux/console.h>
23 #include <linux/cpu.h>
24 #include <linux/freezer.h>
25
26 #include "power.h"
27
28
29 static int noresume = 0;
30 static char resume_file[256] = CONFIG_PM_STD_PARTITION;
31 dev_t swsusp_resume_device;
32 sector_t swsusp_resume_block;
33
34 enum {
35 HIBERNATION_INVALID,
36 HIBERNATION_PLATFORM,
37 HIBERNATION_TEST,
38 HIBERNATION_TESTPROC,
39 HIBERNATION_SHUTDOWN,
40 HIBERNATION_REBOOT,
41 /* keep last */
42 __HIBERNATION_AFTER_LAST
43 };
44 #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
45 #define HIBERNATION_FIRST (HIBERNATION_INVALID + 1)
46
47 static int hibernation_mode = HIBERNATION_SHUTDOWN;
48
49 static struct platform_hibernation_ops *hibernation_ops;
50
51 /**
52 * hibernation_set_ops - set the global hibernate operations
53 * @ops: the hibernation operations to use in subsequent hibernation transitions
54 */
55
hibernation_set_ops(struct platform_hibernation_ops * ops)56 void hibernation_set_ops(struct platform_hibernation_ops *ops)
57 {
58 if (ops && !(ops->begin && ops->end && ops->pre_snapshot
59 && ops->prepare && ops->finish && ops->enter && ops->pre_restore
60 && ops->restore_cleanup)) {
61 WARN_ON(1);
62 return;
63 }
64 mutex_lock(&pm_mutex);
65 hibernation_ops = ops;
66 if (ops)
67 hibernation_mode = HIBERNATION_PLATFORM;
68 else if (hibernation_mode == HIBERNATION_PLATFORM)
69 hibernation_mode = HIBERNATION_SHUTDOWN;
70
71 mutex_unlock(&pm_mutex);
72 }
73
74 static bool entering_platform_hibernation;
75
system_entering_hibernation(void)76 bool system_entering_hibernation(void)
77 {
78 return entering_platform_hibernation;
79 }
80 EXPORT_SYMBOL(system_entering_hibernation);
81
82 #ifdef CONFIG_PM_DEBUG
hibernation_debug_sleep(void)83 static void hibernation_debug_sleep(void)
84 {
85 printk(KERN_INFO "hibernation debug: Waiting for 5 seconds.\n");
86 mdelay(5000);
87 }
88
hibernation_testmode(int mode)89 static int hibernation_testmode(int mode)
90 {
91 if (hibernation_mode == mode) {
92 hibernation_debug_sleep();
93 return 1;
94 }
95 return 0;
96 }
97
hibernation_test(int level)98 static int hibernation_test(int level)
99 {
100 if (pm_test_level == level) {
101 hibernation_debug_sleep();
102 return 1;
103 }
104 return 0;
105 }
106 #else /* !CONFIG_PM_DEBUG */
hibernation_testmode(int mode)107 static int hibernation_testmode(int mode) { return 0; }
hibernation_test(int level)108 static int hibernation_test(int level) { return 0; }
109 #endif /* !CONFIG_PM_DEBUG */
110
111 /**
112 * platform_begin - tell the platform driver that we're starting
113 * hibernation
114 */
115
platform_begin(int platform_mode)116 static int platform_begin(int platform_mode)
117 {
118 return (platform_mode && hibernation_ops) ?
119 hibernation_ops->begin() : 0;
120 }
121
122 /**
123 * platform_end - tell the platform driver that we've entered the
124 * working state
125 */
126
platform_end(int platform_mode)127 static void platform_end(int platform_mode)
128 {
129 if (platform_mode && hibernation_ops)
130 hibernation_ops->end();
131 }
132
133 /**
134 * platform_pre_snapshot - prepare the machine for hibernation using the
135 * platform driver if so configured and return an error code if it fails
136 */
137
platform_pre_snapshot(int platform_mode)138 static int platform_pre_snapshot(int platform_mode)
139 {
140 return (platform_mode && hibernation_ops) ?
141 hibernation_ops->pre_snapshot() : 0;
142 }
143
144 /**
145 * platform_leave - prepare the machine for switching to the normal mode
146 * of operation using the platform driver (called with interrupts disabled)
147 */
148
platform_leave(int platform_mode)149 static void platform_leave(int platform_mode)
150 {
151 if (platform_mode && hibernation_ops)
152 hibernation_ops->leave();
153 }
154
155 /**
156 * platform_finish - switch the machine to the normal mode of operation
157 * using the platform driver (must be called after platform_prepare())
158 */
159
platform_finish(int platform_mode)160 static void platform_finish(int platform_mode)
161 {
162 if (platform_mode && hibernation_ops)
163 hibernation_ops->finish();
164 }
165
166 /**
167 * platform_pre_restore - prepare the platform for the restoration from a
168 * hibernation image. If the restore fails after this function has been
169 * called, platform_restore_cleanup() must be called.
170 */
171
platform_pre_restore(int platform_mode)172 static int platform_pre_restore(int platform_mode)
173 {
174 return (platform_mode && hibernation_ops) ?
175 hibernation_ops->pre_restore() : 0;
176 }
177
178 /**
179 * platform_restore_cleanup - switch the platform to the normal mode of
180 * operation after a failing restore. If platform_pre_restore() has been
181 * called before the failing restore, this function must be called too,
182 * regardless of the result of platform_pre_restore().
183 */
184
platform_restore_cleanup(int platform_mode)185 static void platform_restore_cleanup(int platform_mode)
186 {
187 if (platform_mode && hibernation_ops)
188 hibernation_ops->restore_cleanup();
189 }
190
191 /**
192 * platform_recover - recover the platform from a failure to suspend
193 * devices.
194 */
195
platform_recover(int platform_mode)196 static void platform_recover(int platform_mode)
197 {
198 if (platform_mode && hibernation_ops && hibernation_ops->recover)
199 hibernation_ops->recover();
200 }
201
202 /**
203 * create_image - freeze devices that need to be frozen with interrupts
204 * off, create the hibernation image and thaw those devices. Control
205 * reappears in this routine after a restore.
206 */
207
create_image(int platform_mode)208 static int create_image(int platform_mode)
209 {
210 int error;
211
212 error = arch_prepare_suspend();
213 if (error)
214 return error;
215
216 device_pm_lock();
217 local_irq_disable();
218 /* At this point, device_suspend() has been called, but *not*
219 * device_power_down(). We *must* call device_power_down() now.
220 * Otherwise, drivers for some devices (e.g. interrupt controllers)
221 * become desynchronized with the actual state of the hardware
222 * at resume time, and evil weirdness ensues.
223 */
224 error = device_power_down(PMSG_FREEZE);
225 if (error) {
226 printk(KERN_ERR "PM: Some devices failed to power down, "
227 "aborting hibernation\n");
228 goto Enable_irqs;
229 }
230 sysdev_suspend(PMSG_FREEZE);
231 if (error) {
232 printk(KERN_ERR "PM: Some devices failed to power down, "
233 "aborting hibernation\n");
234 goto Power_up_devices;
235 }
236
237 if (hibernation_test(TEST_CORE))
238 goto Power_up;
239
240 in_suspend = 1;
241 save_processor_state();
242 error = swsusp_arch_suspend();
243 if (error)
244 printk(KERN_ERR "PM: Error %d creating hibernation image\n",
245 error);
246 /* Restore control flow magically appears here */
247 restore_processor_state();
248 if (!in_suspend)
249 platform_leave(platform_mode);
250 Power_up:
251 sysdev_resume();
252 /* NOTE: device_power_up() is just a resume() for devices
253 * that suspended with irqs off ... no overall powerup.
254 */
255 Power_up_devices:
256 device_power_up(in_suspend ?
257 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
258 Enable_irqs:
259 local_irq_enable();
260 device_pm_unlock();
261 return error;
262 }
263
264 /**
265 * hibernation_snapshot - quiesce devices and create the hibernation
266 * snapshot image.
267 * @platform_mode - if set, use the platform driver, if available, to
268 * prepare the platform frimware for the power transition.
269 *
270 * Must be called with pm_mutex held
271 */
272
hibernation_snapshot(int platform_mode)273 int hibernation_snapshot(int platform_mode)
274 {
275 int error;
276
277 error = platform_begin(platform_mode);
278 if (error)
279 return error;
280
281 /* Free memory before shutting down devices. */
282 error = swsusp_shrink_memory();
283 if (error)
284 goto Close;
285
286 suspend_console();
287 error = device_suspend(PMSG_FREEZE);
288 if (error)
289 goto Recover_platform;
290
291 if (hibernation_test(TEST_DEVICES))
292 goto Recover_platform;
293
294 error = platform_pre_snapshot(platform_mode);
295 if (error || hibernation_test(TEST_PLATFORM))
296 goto Finish;
297
298 error = disable_nonboot_cpus();
299 if (!error) {
300 if (hibernation_test(TEST_CPUS))
301 goto Enable_cpus;
302
303 if (hibernation_testmode(HIBERNATION_TEST))
304 goto Enable_cpus;
305
306 error = create_image(platform_mode);
307 /* Control returns here after successful restore */
308 }
309 Enable_cpus:
310 enable_nonboot_cpus();
311 Finish:
312 platform_finish(platform_mode);
313 Resume_devices:
314 device_resume(in_suspend ?
315 (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE);
316 resume_console();
317 Close:
318 platform_end(platform_mode);
319 return error;
320
321 Recover_platform:
322 platform_recover(platform_mode);
323 goto Resume_devices;
324 }
325
326 /**
327 * resume_target_kernel - prepare devices that need to be suspended with
328 * interrupts off, restore the contents of highmem that have not been
329 * restored yet from the image and run the low level code that will restore
330 * the remaining contents of memory and switch to the just restored target
331 * kernel.
332 */
333
resume_target_kernel(void)334 static int resume_target_kernel(void)
335 {
336 int error;
337
338 device_pm_lock();
339 local_irq_disable();
340 error = device_power_down(PMSG_QUIESCE);
341 if (error) {
342 printk(KERN_ERR "PM: Some devices failed to power down, "
343 "aborting resume\n");
344 goto Enable_irqs;
345 }
346 sysdev_suspend(PMSG_QUIESCE);
347 /* We'll ignore saved state, but this gets preempt count (etc) right */
348 save_processor_state();
349 error = restore_highmem();
350 if (!error) {
351 error = swsusp_arch_resume();
352 /*
353 * The code below is only ever reached in case of a failure.
354 * Otherwise execution continues at place where
355 * swsusp_arch_suspend() was called
356 */
357 BUG_ON(!error);
358 /* This call to restore_highmem() undos the previous one */
359 restore_highmem();
360 }
361 /*
362 * The only reason why swsusp_arch_resume() can fail is memory being
363 * very tight, so we have to free it as soon as we can to avoid
364 * subsequent failures
365 */
366 swsusp_free();
367 restore_processor_state();
368 touch_softlockup_watchdog();
369 sysdev_resume();
370 device_power_up(PMSG_RECOVER);
371 Enable_irqs:
372 local_irq_enable();
373 device_pm_unlock();
374 return error;
375 }
376
377 /**
378 * hibernation_restore - quiesce devices and restore the hibernation
379 * snapshot image. If successful, control returns in hibernation_snaphot()
380 * @platform_mode - if set, use the platform driver, if available, to
381 * prepare the platform frimware for the transition.
382 *
383 * Must be called with pm_mutex held
384 */
385
hibernation_restore(int platform_mode)386 int hibernation_restore(int platform_mode)
387 {
388 int error;
389
390 pm_prepare_console();
391 suspend_console();
392 error = device_suspend(PMSG_QUIESCE);
393 if (error)
394 goto Finish;
395
396 error = platform_pre_restore(platform_mode);
397 if (!error) {
398 error = disable_nonboot_cpus();
399 if (!error)
400 error = resume_target_kernel();
401 enable_nonboot_cpus();
402 }
403 platform_restore_cleanup(platform_mode);
404 device_resume(PMSG_RECOVER);
405 Finish:
406 resume_console();
407 pm_restore_console();
408 return error;
409 }
410
411 /**
412 * hibernation_platform_enter - enter the hibernation state using the
413 * platform driver (if available)
414 */
415
hibernation_platform_enter(void)416 int hibernation_platform_enter(void)
417 {
418 int error;
419
420 if (!hibernation_ops)
421 return -ENOSYS;
422
423 /*
424 * We have cancelled the power transition by running
425 * hibernation_ops->finish() before saving the image, so we should let
426 * the firmware know that we're going to enter the sleep state after all
427 */
428 error = hibernation_ops->begin();
429 if (error)
430 goto Close;
431
432 entering_platform_hibernation = true;
433 suspend_console();
434 error = device_suspend(PMSG_HIBERNATE);
435 if (error) {
436 if (hibernation_ops->recover)
437 hibernation_ops->recover();
438 goto Resume_devices;
439 }
440
441 error = hibernation_ops->prepare();
442 if (error)
443 goto Resume_devices;
444
445 error = disable_nonboot_cpus();
446 if (error)
447 goto Finish;
448
449 device_pm_lock();
450 local_irq_disable();
451 error = device_power_down(PMSG_HIBERNATE);
452 if (!error) {
453 sysdev_suspend(PMSG_HIBERNATE);
454 hibernation_ops->enter();
455 /* We should never get here */
456 while (1);
457 }
458 local_irq_enable();
459 device_pm_unlock();
460
461 /*
462 * We don't need to reenable the nonboot CPUs or resume consoles, since
463 * the system is going to be halted anyway.
464 */
465 Finish:
466 hibernation_ops->finish();
467 Resume_devices:
468 entering_platform_hibernation = false;
469 device_resume(PMSG_RESTORE);
470 resume_console();
471 Close:
472 hibernation_ops->end();
473 return error;
474 }
475
476 /**
477 * power_down - Shut the machine down for hibernation.
478 *
479 * Use the platform driver, if configured so; otherwise try
480 * to power off or reboot.
481 */
482
power_down(void)483 static void power_down(void)
484 {
485 switch (hibernation_mode) {
486 case HIBERNATION_TEST:
487 case HIBERNATION_TESTPROC:
488 break;
489 case HIBERNATION_REBOOT:
490 kernel_restart(NULL);
491 break;
492 case HIBERNATION_PLATFORM:
493 hibernation_platform_enter();
494 case HIBERNATION_SHUTDOWN:
495 kernel_power_off();
496 break;
497 }
498 kernel_halt();
499 /*
500 * Valid image is on the disk, if we continue we risk serious data
501 * corruption after resume.
502 */
503 printk(KERN_CRIT "PM: Please power down manually\n");
504 while(1);
505 }
506
prepare_processes(void)507 static int prepare_processes(void)
508 {
509 int error = 0;
510
511 if (freeze_processes()) {
512 error = -EBUSY;
513 thaw_processes();
514 }
515 return error;
516 }
517
518 /**
519 * hibernate - The granpappy of the built-in hibernation management
520 */
521
hibernate(void)522 int hibernate(void)
523 {
524 int error;
525
526 mutex_lock(&pm_mutex);
527 /* The snapshot device should not be opened while we're running */
528 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
529 error = -EBUSY;
530 goto Unlock;
531 }
532
533 pm_prepare_console();
534 error = pm_notifier_call_chain(PM_HIBERNATION_PREPARE);
535 if (error)
536 goto Exit;
537
538 error = usermodehelper_disable();
539 if (error)
540 goto Exit;
541
542 /* Allocate memory management structures */
543 error = create_basic_memory_bitmaps();
544 if (error)
545 goto Exit;
546
547 printk(KERN_INFO "PM: Syncing filesystems ... ");
548 sys_sync();
549 printk("done.\n");
550
551 error = prepare_processes();
552 if (error)
553 goto Finish;
554
555 if (hibernation_test(TEST_FREEZER))
556 goto Thaw;
557
558 if (hibernation_testmode(HIBERNATION_TESTPROC))
559 goto Thaw;
560
561 error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM);
562 if (in_suspend && !error) {
563 unsigned int flags = 0;
564
565 if (hibernation_mode == HIBERNATION_PLATFORM)
566 flags |= SF_PLATFORM_MODE;
567 pr_debug("PM: writing image.\n");
568 error = swsusp_write(flags);
569 swsusp_free();
570 if (!error)
571 power_down();
572 } else {
573 pr_debug("PM: Image restored successfully.\n");
574 swsusp_free();
575 }
576 Thaw:
577 thaw_processes();
578 Finish:
579 free_basic_memory_bitmaps();
580 usermodehelper_enable();
581 Exit:
582 pm_notifier_call_chain(PM_POST_HIBERNATION);
583 pm_restore_console();
584 atomic_inc(&snapshot_device_available);
585 Unlock:
586 mutex_unlock(&pm_mutex);
587 return error;
588 }
589
590
591 /**
592 * software_resume - Resume from a saved image.
593 *
594 * Called as a late_initcall (so all devices are discovered and
595 * initialized), we call swsusp to see if we have a saved image or not.
596 * If so, we quiesce devices, the restore the saved image. We will
597 * return above (in hibernate() ) if everything goes well.
598 * Otherwise, we fail gracefully and return to the normally
599 * scheduled program.
600 *
601 */
602
software_resume(void)603 static int software_resume(void)
604 {
605 int error;
606 unsigned int flags;
607
608 /*
609 * If the user said "noresume".. bail out early.
610 */
611 if (noresume)
612 return 0;
613
614 /*
615 * name_to_dev_t() below takes a sysfs buffer mutex when sysfs
616 * is configured into the kernel. Since the regular hibernate
617 * trigger path is via sysfs which takes a buffer mutex before
618 * calling hibernate functions (which take pm_mutex) this can
619 * cause lockdep to complain about a possible ABBA deadlock
620 * which cannot happen since we're in the boot code here and
621 * sysfs can't be invoked yet. Therefore, we use a subclass
622 * here to avoid lockdep complaining.
623 */
624 mutex_lock_nested(&pm_mutex, SINGLE_DEPTH_NESTING);
625 if (!swsusp_resume_device) {
626 if (!strlen(resume_file)) {
627 mutex_unlock(&pm_mutex);
628 return -ENOENT;
629 }
630 /*
631 * Some device discovery might still be in progress; we need
632 * to wait for this to finish.
633 */
634 wait_for_device_probe();
635 swsusp_resume_device = name_to_dev_t(resume_file);
636 pr_debug("PM: Resume from partition %s\n", resume_file);
637 } else {
638 pr_debug("PM: Resume from partition %d:%d\n",
639 MAJOR(swsusp_resume_device),
640 MINOR(swsusp_resume_device));
641 }
642
643 if (noresume) {
644 /**
645 * FIXME: If noresume is specified, we need to find the
646 * partition and reset it back to normal swap space.
647 */
648 mutex_unlock(&pm_mutex);
649 return 0;
650 }
651
652 pr_debug("PM: Checking hibernation image.\n");
653 error = swsusp_check();
654 if (error)
655 goto Unlock;
656
657 /* The snapshot device should not be opened while we're running */
658 if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
659 error = -EBUSY;
660 goto Unlock;
661 }
662
663 pm_prepare_console();
664 error = pm_notifier_call_chain(PM_RESTORE_PREPARE);
665 if (error)
666 goto Finish;
667
668 error = usermodehelper_disable();
669 if (error)
670 goto Finish;
671
672 error = create_basic_memory_bitmaps();
673 if (error)
674 goto Finish;
675
676 pr_debug("PM: Preparing processes for restore.\n");
677 error = prepare_processes();
678 if (error) {
679 swsusp_close(FMODE_READ);
680 goto Done;
681 }
682
683 pr_debug("PM: Reading hibernation image.\n");
684
685 error = swsusp_read(&flags);
686 if (!error)
687 hibernation_restore(flags & SF_PLATFORM_MODE);
688
689 printk(KERN_ERR "PM: Restore failed, recovering.\n");
690 swsusp_free();
691 thaw_processes();
692 Done:
693 free_basic_memory_bitmaps();
694 usermodehelper_enable();
695 Finish:
696 pm_notifier_call_chain(PM_POST_RESTORE);
697 pm_restore_console();
698 atomic_inc(&snapshot_device_available);
699 /* For success case, the suspend path will release the lock */
700 Unlock:
701 mutex_unlock(&pm_mutex);
702 pr_debug("PM: Resume from disk failed.\n");
703 return error;
704 }
705
706 late_initcall(software_resume);
707
708
709 static const char * const hibernation_modes[] = {
710 [HIBERNATION_PLATFORM] = "platform",
711 [HIBERNATION_SHUTDOWN] = "shutdown",
712 [HIBERNATION_REBOOT] = "reboot",
713 [HIBERNATION_TEST] = "test",
714 [HIBERNATION_TESTPROC] = "testproc",
715 };
716
717 /**
718 * disk - Control hibernation mode
719 *
720 * Suspend-to-disk can be handled in several ways. We have a few options
721 * for putting the system to sleep - using the platform driver (e.g. ACPI
722 * or other hibernation_ops), powering off the system or rebooting the
723 * system (for testing) as well as the two test modes.
724 *
725 * The system can support 'platform', and that is known a priori (and
726 * encoded by the presence of hibernation_ops). However, the user may
727 * choose 'shutdown' or 'reboot' as alternatives, as well as one fo the
728 * test modes, 'test' or 'testproc'.
729 *
730 * show() will display what the mode is currently set to.
731 * store() will accept one of
732 *
733 * 'platform'
734 * 'shutdown'
735 * 'reboot'
736 * 'test'
737 * 'testproc'
738 *
739 * It will only change to 'platform' if the system
740 * supports it (as determined by having hibernation_ops).
741 */
742
disk_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)743 static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr,
744 char *buf)
745 {
746 int i;
747 char *start = buf;
748
749 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
750 if (!hibernation_modes[i])
751 continue;
752 switch (i) {
753 case HIBERNATION_SHUTDOWN:
754 case HIBERNATION_REBOOT:
755 case HIBERNATION_TEST:
756 case HIBERNATION_TESTPROC:
757 break;
758 case HIBERNATION_PLATFORM:
759 if (hibernation_ops)
760 break;
761 /* not a valid mode, continue with loop */
762 continue;
763 }
764 if (i == hibernation_mode)
765 buf += sprintf(buf, "[%s] ", hibernation_modes[i]);
766 else
767 buf += sprintf(buf, "%s ", hibernation_modes[i]);
768 }
769 buf += sprintf(buf, "\n");
770 return buf-start;
771 }
772
773
disk_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t n)774 static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr,
775 const char *buf, size_t n)
776 {
777 int error = 0;
778 int i;
779 int len;
780 char *p;
781 int mode = HIBERNATION_INVALID;
782
783 p = memchr(buf, '\n', n);
784 len = p ? p - buf : n;
785
786 mutex_lock(&pm_mutex);
787 for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) {
788 if (len == strlen(hibernation_modes[i])
789 && !strncmp(buf, hibernation_modes[i], len)) {
790 mode = i;
791 break;
792 }
793 }
794 if (mode != HIBERNATION_INVALID) {
795 switch (mode) {
796 case HIBERNATION_SHUTDOWN:
797 case HIBERNATION_REBOOT:
798 case HIBERNATION_TEST:
799 case HIBERNATION_TESTPROC:
800 hibernation_mode = mode;
801 break;
802 case HIBERNATION_PLATFORM:
803 if (hibernation_ops)
804 hibernation_mode = mode;
805 else
806 error = -EINVAL;
807 }
808 } else
809 error = -EINVAL;
810
811 if (!error)
812 pr_debug("PM: Hibernation mode set to '%s'\n",
813 hibernation_modes[mode]);
814 mutex_unlock(&pm_mutex);
815 return error ? error : n;
816 }
817
818 power_attr(disk);
819
resume_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)820 static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
821 char *buf)
822 {
823 return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
824 MINOR(swsusp_resume_device));
825 }
826
resume_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t n)827 static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
828 const char *buf, size_t n)
829 {
830 unsigned int maj, min;
831 dev_t res;
832 int ret = -EINVAL;
833
834 if (sscanf(buf, "%u:%u", &maj, &min) != 2)
835 goto out;
836
837 res = MKDEV(maj,min);
838 if (maj != MAJOR(res) || min != MINOR(res))
839 goto out;
840
841 mutex_lock(&pm_mutex);
842 swsusp_resume_device = res;
843 mutex_unlock(&pm_mutex);
844 printk(KERN_INFO "PM: Starting manual resume from disk\n");
845 noresume = 0;
846 software_resume();
847 ret = n;
848 out:
849 return ret;
850 }
851
852 power_attr(resume);
853
image_size_show(struct kobject * kobj,struct kobj_attribute * attr,char * buf)854 static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr,
855 char *buf)
856 {
857 return sprintf(buf, "%lu\n", image_size);
858 }
859
image_size_store(struct kobject * kobj,struct kobj_attribute * attr,const char * buf,size_t n)860 static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr,
861 const char *buf, size_t n)
862 {
863 unsigned long size;
864
865 if (sscanf(buf, "%lu", &size) == 1) {
866 image_size = size;
867 return n;
868 }
869
870 return -EINVAL;
871 }
872
873 power_attr(image_size);
874
875 static struct attribute * g[] = {
876 &disk_attr.attr,
877 &resume_attr.attr,
878 &image_size_attr.attr,
879 NULL,
880 };
881
882
883 static struct attribute_group attr_group = {
884 .attrs = g,
885 };
886
887
pm_disk_init(void)888 static int __init pm_disk_init(void)
889 {
890 return sysfs_create_group(power_kobj, &attr_group);
891 }
892
893 core_initcall(pm_disk_init);
894
895
resume_setup(char * str)896 static int __init resume_setup(char *str)
897 {
898 if (noresume)
899 return 1;
900
901 strncpy( resume_file, str, 255 );
902 return 1;
903 }
904
resume_offset_setup(char * str)905 static int __init resume_offset_setup(char *str)
906 {
907 unsigned long long offset;
908
909 if (noresume)
910 return 1;
911
912 if (sscanf(str, "%llu", &offset) == 1)
913 swsusp_resume_block = offset;
914
915 return 1;
916 }
917
noresume_setup(char * str)918 static int __init noresume_setup(char *str)
919 {
920 noresume = 1;
921 return 1;
922 }
923
924 __setup("noresume", noresume_setup);
925 __setup("resume_offset=", resume_offset_setup);
926 __setup("resume=", resume_setup);
927