1 // SPDX-License-Identifier: GPL-2.0-only
3  * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support.
72 #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1)
85 	return atomic_add_unless(&hibernate_atomic, -1, 0);  in hibernate_acquire()
101  * hibernation_set_ops - Set the global hibernate operations.
108 	if (ops && !(ops->begin && ops->end &&  ops->pre_snapshot  in hibernation_set_ops()
109 	    && ops->prepare && ops->finish && ops->enter && ops->pre_restore  in hibernation_set_ops()
110 	    && ops->restore_cleanup && ops->leave)) {  in hibernation_set_ops()
155  * platform_begin - Call platform to start hibernation.
161 		hibernation_ops->begin(PMSG_FREEZE) : 0;  in platform_begin()
165  * platform_end - Call platform to finish transition to the working state.
171 		hibernation_ops->end();  in platform_end()
175  * platform_pre_snapshot - Call platform to prepare the machine for hibernation.
185 		hibernation_ops->pre_snapshot() : 0;  in platform_pre_snapshot()
189  * platform_leave - Call platform to prepare a transition to the working state.
200 		hibernation_ops->leave();  in platform_leave()
204  * platform_finish - Call platform to switch the system to the working state.
215 		hibernation_ops->finish();  in platform_finish()
219  * platform_pre_restore - Prepare for hibernate image restoration.
222  * Use the platform driver to prepare the system for resume from a hibernation
231 		hibernation_ops->pre_restore() : 0;  in platform_pre_restore()
235  * platform_restore_cleanup - Switch to the working state after failing restore.
248 		hibernation_ops->restore_cleanup();  in platform_restore_cleanup()
252  * platform_recover - Recover from a failure to suspend devices.
257 	if (platform_mode && hibernation_ops && hibernation_ops->recover)  in platform_recover()
258 		hibernation_ops->recover();  in platform_recover()
262  * swsusp_show_speed - Print time elapsed between two events during hibernation.
281 		centisecs = 1;	/* avoid div-by-zero */  in swsusp_show_speed()
295  * create_image - Create a hibernation image.
361 	/* Allow architectures to do nosmt-specific post-resume dances */  in create_image()
375  * hibernation_snapshot - Quiesce devices and create a hibernation image.
461  * resume_target_kernel - Restore system state from a hibernation image.
466  * the low-level code that will restore the remaining contents of memory and
475 		pr_err("Some devices failed to power down, aborting resume\n");  in resume_target_kernel()
539  * hibernation_restore - Quiesce devices and restore from a hibernation image.
571  * hibernation_platform_enter - Power off the system using the platform driver.
578 		return -ENOSYS;  in hibernation_platform_enter()
582 	 * hibernation_ops->finish() before saving the image, so we should let  in hibernation_platform_enter()
585 	error = hibernation_ops->begin(PMSG_HIBERNATE);  in hibernation_platform_enter()
593 		if (hibernation_ops->recover)  in hibernation_platform_enter()
594 			hibernation_ops->recover();  in hibernation_platform_enter()
602 	error = hibernation_ops->prepare();  in hibernation_platform_enter()
618 		error = -EAGAIN;  in hibernation_platform_enter()
622 	hibernation_ops->enter();  in hibernation_platform_enter()
636 	hibernation_ops->finish();  in hibernation_platform_enter()
646 	hibernation_ops->end();  in hibernation_platform_enter()
652  * power_down - Shut the machine down for hibernation.
673 				pr_err("Swap will be unusable! Try swapon -a.\n");  in power_down()
686 		if (error == -EAGAIN || error == -EBUSY) {  in power_down()
704 	 * corruption after resume.  in power_down()
743  * hibernate - Carry out system hibernation, including saving the image.
753 		return -EPERM;  in hibernate()
763 			return -EOPNOTSUPP;  in hibernate()
770 		error = -EBUSY;  in hibernate()
861  * hibernate_quiet_exec - Execute a function with all devices frozen.
875 		error = -EBUSY;  in hibernate_quiet_exec()
961 		return -ENOENT;  in find_resume_device()
966 		pr_info("Waiting %dsec before reading resume device ...\n",  in find_resume_device()
1014 			error = -EOPNOTSUPP;  in software_resume()
1021 		error = -EBUSY;  in software_resume()
1026 	pr_info("resume from hibernation\n");  in software_resume()
1049 	pr_info("resume failed (%d)\n", error);  in software_resume()
1062  * software_resume_initcall - Resume from a saved hibernation image.
1107  * /sys/power/disk - Control hibernation mode.
1166 		buf[count - 1] = '\n';  in disk_show()
1182 		return -EPERM;  in disk_store()
1185 	len = p ? p - buf : n;  in disk_store()
1209 				error = -EINVAL;  in disk_store()
1212 		error = -EINVAL;  in disk_store()
1242 	if (len && buf[len-1] == '\n')  in resume_store()
1243 		len--;  in resume_store()
1246 		return -ENOMEM;  in resume_store()
1250 		unsigned maj, min, offset;  in resume_store()  local
1255 		    sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset,  in resume_store()
1259 				error = -EINVAL;  in resume_store()
1263 				error = -EINVAL;  in resume_store()
1274 	pm_pr_dbg("Configured hibernation resume from disk to %u\n",  in resume_store()
1281 power_attr(resume);
1293 	unsigned long long offset;  in resume_offset_store()  local
1296 	rc = kstrtoull(buf, 0, &offset);  in resume_offset_store()
1299 	swsusp_resume_block = offset;  in resume_offset_store()
1322 	return -EINVAL;  in image_size_store()
1344 	return -EINVAL;  in reserved_size_store()
1383 	unsigned long long offset;  in resume_offset_setup()  local
1388 	if (sscanf(str, "%llu", &offset) == 1)  in resume_offset_setup()
1389 		swsusp_resume_block = offset;  in resume_offset_setup()
1453 		return -EBUSY;  in hibernate_compressor_param_set()
1491 __setup("resume=", resume_setup);