// SPDX-License-Identifier: GPL-2.0-only /* * kernel/power/hibernate.c - Hibernation (a.k.a suspend-to-disk) support. * * Copyright (c) 2003 Patrick Mochel * Copyright (c) 2003 Open Source Development Lab * Copyright (c) 2004 Pavel Machek * Copyright (c) 2009 Rafael J. Wysocki, Novell Inc. * Copyright (C) 2012 Bojan Smojver */ #define pr_fmt(fmt) "PM: hibernation: " fmt #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "power.h" static int nocompress; static int noresume; static int nohibernate; static int resume_wait; static unsigned int resume_delay; static char resume_file[256] = CONFIG_PM_STD_PARTITION; dev_t swsusp_resume_device; sector_t swsusp_resume_block; __visible int in_suspend __nosavedata; static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP; /* * Compression/decompression algorithm to be used while saving/loading * image to/from disk. This would later be used in 'kernel/power/swap.c' * to allocate comp streams. */ char hib_comp_algo[CRYPTO_MAX_ALG_NAME]; enum { HIBERNATION_INVALID, HIBERNATION_PLATFORM, HIBERNATION_SHUTDOWN, HIBERNATION_REBOOT, #ifdef CONFIG_SUSPEND HIBERNATION_SUSPEND, #endif HIBERNATION_TEST_RESUME, /* keep last */ __HIBERNATION_AFTER_LAST }; #define HIBERNATION_MAX (__HIBERNATION_AFTER_LAST-1) #define HIBERNATION_FIRST (HIBERNATION_INVALID + 1) static int hibernation_mode = HIBERNATION_SHUTDOWN; bool freezer_test_done; static const struct platform_hibernation_ops *hibernation_ops; static atomic_t hibernate_atomic = ATOMIC_INIT(1); bool hibernate_acquire(void) { return atomic_add_unless(&hibernate_atomic, -1, 0); } void hibernate_release(void) { atomic_inc(&hibernate_atomic); } bool hibernation_available(void) { return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION) && !secretmem_active() && !cxl_mem_active(); } /** * hibernation_set_ops - Set the global hibernate operations. * @ops: Hibernation operations to use in subsequent hibernation transitions. */ void hibernation_set_ops(const struct platform_hibernation_ops *ops) { unsigned int sleep_flags; if (ops && !(ops->begin && ops->end && ops->pre_snapshot && ops->prepare && ops->finish && ops->enter && ops->pre_restore && ops->restore_cleanup && ops->leave)) { WARN_ON(1); return; } sleep_flags = lock_system_sleep(); hibernation_ops = ops; if (ops) hibernation_mode = HIBERNATION_PLATFORM; else if (hibernation_mode == HIBERNATION_PLATFORM) hibernation_mode = HIBERNATION_SHUTDOWN; unlock_system_sleep(sleep_flags); } EXPORT_SYMBOL_GPL(hibernation_set_ops); static bool entering_platform_hibernation; bool system_entering_hibernation(void) { return entering_platform_hibernation; } EXPORT_SYMBOL(system_entering_hibernation); #ifdef CONFIG_PM_DEBUG static void hibernation_debug_sleep(void) { pr_info("debug: Waiting for 5 seconds.\n"); mdelay(5000); } static int hibernation_test(int level) { if (pm_test_level == level) { hibernation_debug_sleep(); return 1; } return 0; } #else /* !CONFIG_PM_DEBUG */ static int hibernation_test(int level) { return 0; } #endif /* !CONFIG_PM_DEBUG */ /** * platform_begin - Call platform to start hibernation. * @platform_mode: Whether or not to use the platform driver. */ static int platform_begin(int platform_mode) { return (platform_mode && hibernation_ops) ? hibernation_ops->begin(PMSG_FREEZE) : 0; } /** * platform_end - Call platform to finish transition to the working state. * @platform_mode: Whether or not to use the platform driver. */ static void platform_end(int platform_mode) { if (platform_mode && hibernation_ops) hibernation_ops->end(); } /** * platform_pre_snapshot - Call platform to prepare the machine for hibernation. * @platform_mode: Whether or not to use the platform driver. * * Use the platform driver to prepare the system for creating a hibernate image, * if so configured, and return an error code if that fails. */ static int platform_pre_snapshot(int platform_mode) { return (platform_mode && hibernation_ops) ? hibernation_ops->pre_snapshot() : 0; } /** * platform_leave - Call platform to prepare a transition to the working state. * @platform_mode: Whether or not to use the platform driver. * * Use the platform driver prepare to prepare the machine for switching to the * normal mode of operation. * * This routine is called on one CPU with interrupts disabled. */ static void platform_leave(int platform_mode) { if (platform_mode && hibernation_ops) hibernation_ops->leave(); } /** * platform_finish - Call platform to switch the system to the working state. * @platform_mode: Whether or not to use the platform driver. * * Use the platform driver to switch the machine to the normal mode of * operation. * * This routine must be called after platform_prepare(). */ static void platform_finish(int platform_mode) { if (platform_mode && hibernation_ops) hibernation_ops->finish(); } /** * platform_pre_restore - Prepare for hibernate image restoration. * @platform_mode: Whether or not to use the platform driver. * * Use the platform driver to prepare the system for resume from a hibernation * image. * * If the restore fails after this function has been called, * platform_restore_cleanup() must be called. */ static int platform_pre_restore(int platform_mode) { return (platform_mode && hibernation_ops) ? hibernation_ops->pre_restore() : 0; } /** * platform_restore_cleanup - Switch to the working state after failing restore. * @platform_mode: Whether or not to use the platform driver. * * Use the platform driver to switch the system to the normal mode of operation * after a failing restore. * * If platform_pre_restore() has been called before the failing restore, this * function must be called too, regardless of the result of * platform_pre_restore(). */ static void platform_restore_cleanup(int platform_mode) { if (platform_mode && hibernation_ops) hibernation_ops->restore_cleanup(); } /** * platform_recover - Recover from a failure to suspend devices. * @platform_mode: Whether or not to use the platform driver. */ static void platform_recover(int platform_mode) { if (platform_mode && hibernation_ops && hibernation_ops->recover) hibernation_ops->recover(); } /** * swsusp_show_speed - Print time elapsed between two events during hibernation. * @start: Starting event. * @stop: Final event. * @nr_pages: Number of memory pages processed between @start and @stop. * @msg: Additional diagnostic message to print. */ void swsusp_show_speed(ktime_t start, ktime_t stop, unsigned nr_pages, char *msg) { ktime_t diff; u64 elapsed_centisecs64; unsigned int centisecs; unsigned int k; unsigned int kps; diff = ktime_sub(stop, start); elapsed_centisecs64 = ktime_divns(diff, 10*NSEC_PER_MSEC); centisecs = elapsed_centisecs64; if (centisecs == 0) centisecs = 1; /* avoid div-by-zero */ k = nr_pages * (PAGE_SIZE / 1024); kps = (k * 100) / centisecs; pr_info("%s %u kbytes in %u.%02u seconds (%u.%02u MB/s)\n", msg, k, centisecs / 100, centisecs % 100, kps / 1000, (kps % 1000) / 10); } __weak int arch_resume_nosmt(void) { return 0; } /** * create_image - Create a hibernation image. * @platform_mode: Whether or not to use the platform driver. * * Execute device drivers' "late" and "noirq" freeze callbacks, create a * hibernation image and run the drivers' "noirq" and "early" thaw callbacks. * * Control reappears in this routine after the subsequent restore. */ static int create_image(int platform_mode) { int error; error = dpm_suspend_end(PMSG_FREEZE); if (error) { pr_err("Some devices failed to power down, aborting\n"); return error; } error = platform_pre_snapshot(platform_mode); if (error || hibernation_test(TEST_PLATFORM)) goto Platform_finish; error = pm_sleep_disable_secondary_cpus(); if (error || hibernation_test(TEST_CPUS)) goto Enable_cpus; local_irq_disable(); system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) { pr_err("Some system devices failed to power down, aborting\n"); goto Enable_irqs; } if (hibernation_test(TEST_CORE) || pm_wakeup_pending()) goto Power_up; in_suspend = 1; save_processor_state(); trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, true); error = swsusp_arch_suspend(); /* Restore control flow magically appears here */ restore_processor_state(); trace_suspend_resume(TPS("machine_suspend"), PM_EVENT_HIBERNATE, false); if (error) pr_err("Error %d creating image\n", error); if (!in_suspend) { events_check_enabled = false; clear_or_poison_free_pages(); } platform_leave(platform_mode); Power_up: syscore_resume(); Enable_irqs: system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: pm_sleep_enable_secondary_cpus(); /* Allow architectures to do nosmt-specific post-resume dances */ if (!in_suspend) error = arch_resume_nosmt(); Platform_finish: platform_finish(platform_mode); dpm_resume_start(in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE); return error; } /** * hibernation_snapshot - Quiesce devices and create a hibernation image. * @platform_mode: If set, use platform driver to prepare for the transition. * * This routine must be called with system_transition_mutex held. */ int hibernation_snapshot(int platform_mode) { pm_message_t msg; int error; pm_suspend_clear_flags(); error = platform_begin(platform_mode); if (error) goto Close; /* Preallocate image memory before shutting down devices. */ error = hibernate_preallocate_memory(); if (error) goto Close; error = freeze_kernel_threads(); if (error) goto Cleanup; if (hibernation_test(TEST_FREEZER)) { /* * Indicate to the caller that we are returning due to a * successful freezer test. */ freezer_test_done = true; goto Thaw; } error = dpm_prepare(PMSG_FREEZE); if (error) { dpm_complete(PMSG_RECOVER); goto Thaw; } suspend_console(); pm_restrict_gfp_mask(); error = dpm_suspend(PMSG_FREEZE); if (error || hibernation_test(TEST_DEVICES)) platform_recover(platform_mode); else error = create_image(platform_mode); /* * In the case that we call create_image() above, the control * returns here (1) after the image has been created or the * image creation has failed and (2) after a successful restore. */ /* We may need to release the preallocated image pages here. */ if (error || !in_suspend) swsusp_free(); msg = in_suspend ? (error ? PMSG_RECOVER : PMSG_THAW) : PMSG_RESTORE; dpm_resume(msg); if (error || !in_suspend) pm_restore_gfp_mask(); resume_console(); dpm_complete(msg); Close: platform_end(platform_mode); return error; Thaw: thaw_kernel_threads(); Cleanup: swsusp_free(); goto Close; } int __weak hibernate_resume_nonboot_cpu_disable(void) { return suspend_disable_secondary_cpus(); } /** * resume_target_kernel - Restore system state from a hibernation image. * @platform_mode: Whether or not to use the platform driver. * * Execute device drivers' "noirq" and "late" freeze callbacks, restore the * contents of highmem that have not been restored yet from the image and run * the low-level code that will restore the remaining contents of memory and * switch to the just restored target kernel. */ static int resume_target_kernel(bool platform_mode) { int error; error = dpm_suspend_end(PMSG_QUIESCE); if (error) { pr_err("Some devices failed to power down, aborting resume\n"); return error; } error = platform_pre_restore(platform_mode); if (error) goto Cleanup; cpuidle_pause(); error = hibernate_resume_nonboot_cpu_disable(); if (error) goto Enable_cpus; local_irq_disable(); system_state = SYSTEM_SUSPEND; error = syscore_suspend(); if (error) goto Enable_irqs; save_processor_state(); error = restore_highmem(); if (!error) { error = swsusp_arch_resume(); /* * The code below is only ever reached in case of a failure. * Otherwise, execution continues at the place where * swsusp_arch_suspend() was called. */ BUG_ON(!error); /* * This call to restore_highmem() reverts the changes made by * the previous one. */ restore_highmem(); } /* * The only reason why swsusp_arch_resume() can fail is memory being * very tight, so we have to free it as soon as we can to avoid * subsequent failures. */ swsusp_free(); restore_processor_state(); touch_softlockup_watchdog(); syscore_resume(); Enable_irqs: system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: pm_sleep_enable_secondary_cpus(); Cleanup: platform_restore_cleanup(platform_mode); dpm_resume_start(PMSG_RECOVER); return error; } /** * hibernation_restore - Quiesce devices and restore from a hibernation image. * @platform_mode: If set, use platform driver to prepare for the transition. * * This routine must be called with system_transition_mutex held. If it is * successful, control reappears in the restored target kernel in * hibernation_snapshot(). */ int hibernation_restore(int platform_mode) { int error; pm_prepare_console(); suspend_console(); pm_restrict_gfp_mask(); error = dpm_suspend_start(PMSG_QUIESCE); if (!error) { error = resume_target_kernel(platform_mode); /* * The above should either succeed and jump to the new kernel, * or return with an error. Otherwise things are just * undefined, so let's be paranoid. */ BUG_ON(!error); } dpm_resume_end(PMSG_RECOVER); pm_restore_gfp_mask(); resume_console(); pm_restore_console(); return error; } /** * hibernation_platform_enter - Power off the system using the platform driver. */ int hibernation_platform_enter(void) { int error; if (!hibernation_ops) return -ENOSYS; /* * We have cancelled the power transition by running * hibernation_ops->finish() before saving the image, so we should let * the firmware know that we're going to enter the sleep state after all */ error = hibernation_ops->begin(PMSG_HIBERNATE); if (error) goto Close; entering_platform_hibernation = true; suspend_console(); error = dpm_suspend_start(PMSG_HIBERNATE); if (error) { if (hibernation_ops->recover) hibernation_ops->recover(); goto Resume_devices; } error = dpm_suspend_end(PMSG_HIBERNATE); if (error) goto Resume_devices; error = hibernation_ops->prepare(); if (error) goto Platform_finish; error = pm_sleep_disable_secondary_cpus(); if (error) goto Enable_cpus; local_irq_disable(); system_state = SYSTEM_SUSPEND; syscore_suspend(); if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; } hibernation_ops->enter(); /* We should never get here */ while (1); Power_up: syscore_resume(); system_state = SYSTEM_RUNNING; local_irq_enable(); Enable_cpus: pm_sleep_enable_secondary_cpus(); Platform_finish: hibernation_ops->finish(); dpm_resume_start(PMSG_RESTORE); Resume_devices: entering_platform_hibernation = false; dpm_resume_end(PMSG_RESTORE); resume_console(); Close: hibernation_ops->end(); return error; } /** * power_down - Shut the machine down for hibernation. * * Use the platform driver, if configured, to put the system into the sleep * state corresponding to hibernation, or try to power it off or reboot, * depending on the value of hibernation_mode. */ static void power_down(void) { int error; #ifdef CONFIG_SUSPEND if (hibernation_mode == HIBERNATION_SUSPEND) { error = suspend_devices_and_enter(mem_sleep_current); if (error) { hibernation_mode = hibernation_ops ? HIBERNATION_PLATFORM : HIBERNATION_SHUTDOWN; } else { /* Restore swap signature. */ error = swsusp_unmark(); if (error) pr_err("Swap will be unusable! Try swapon -a.\n"); return; } } #endif switch (hibernation_mode) { case HIBERNATION_REBOOT: kernel_restart(NULL); break; case HIBERNATION_PLATFORM: error = hibernation_platform_enter(); if (error == -EAGAIN || error == -EBUSY) { swsusp_unmark(); events_check_enabled = false; pr_info("Wakeup event detected during hibernation, rolling back.\n"); return; } fallthrough; case HIBERNATION_SHUTDOWN: if (kernel_can_power_off()) { entering_platform_hibernation = true; kernel_power_off(); entering_platform_hibernation = false; } break; } kernel_halt(); /* * Valid image is on the disk, if we continue we risk serious data * corruption after resume. */ pr_crit("Power down manually\n"); while (1) cpu_relax(); } static int load_image_and_restore(void) { int error; unsigned int flags; pm_pr_dbg("Loading hibernation image.\n"); lock_device_hotplug(); error = create_basic_memory_bitmaps(); if (error) { swsusp_close(); goto Unlock; } error = swsusp_read(&flags); swsusp_close(); if (!error) error = hibernation_restore(flags & SF_PLATFORM_MODE); pr_err("Failed to load image, recovering.\n"); swsusp_free(); free_basic_memory_bitmaps(); Unlock: unlock_device_hotplug(); return error; } #define COMPRESSION_ALGO_LZO "lzo" #define COMPRESSION_ALGO_LZ4 "lz4" /** * hibernate - Carry out system hibernation, including saving the image. */ int hibernate(void) { bool snapshot_test = false; unsigned int sleep_flags; int error; if (!hibernation_available()) { pm_pr_dbg("Hibernation not available.\n"); return -EPERM; } /* * Query for the compression algorithm support if compression is enabled. */ if (!nocompress) { strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo)); if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) { pr_err("%s compression is not available\n", hib_comp_algo); return -EOPNOTSUPP; } } sleep_flags = lock_system_sleep(); /* The snapshot device should not be opened while we're running */ if (!hibernate_acquire()) { error = -EBUSY; goto Unlock; } pr_info("hibernation entry\n"); pm_prepare_console(); error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION); if (error) goto Restore; ksys_sync_helper(); error = freeze_processes(); if (error) goto Exit; lock_device_hotplug(); /* Allocate memory management structures */ error = create_basic_memory_bitmaps(); if (error) goto Thaw; error = hibernation_snapshot(hibernation_mode == HIBERNATION_PLATFORM); if (error || freezer_test_done) goto Free_bitmaps; if (in_suspend) { unsigned int flags = 0; if (hibernation_mode == HIBERNATION_PLATFORM) flags |= SF_PLATFORM_MODE; if (nocompress) { flags |= SF_NOCOMPRESS_MODE; } else { flags |= SF_CRC32_MODE; /* * By default, LZO compression is enabled. Use SF_COMPRESSION_ALG_LZ4 * to override this behaviour and use LZ4. * * Refer kernel/power/power.h for more details */ if (!strcmp(hib_comp_algo, COMPRESSION_ALGO_LZ4)) flags |= SF_COMPRESSION_ALG_LZ4; else flags |= SF_COMPRESSION_ALG_LZO; } pm_pr_dbg("Writing hibernation image.\n"); error = swsusp_write(flags); swsusp_free(); if (!error) { if (hibernation_mode == HIBERNATION_TEST_RESUME) snapshot_test = true; else power_down(); } in_suspend = 0; pm_restore_gfp_mask(); } else { pm_pr_dbg("Hibernation image restored successfully.\n"); } Free_bitmaps: free_basic_memory_bitmaps(); Thaw: unlock_device_hotplug(); if (snapshot_test) { pm_pr_dbg("Checking hibernation image\n"); error = swsusp_check(false); if (!error) error = load_image_and_restore(); } thaw_processes(); /* Don't bother checking whether freezer_test_done is true */ freezer_test_done = false; Exit: pm_notifier_call_chain(PM_POST_HIBERNATION); Restore: pm_restore_console(); hibernate_release(); Unlock: unlock_system_sleep(sleep_flags); pr_info("hibernation exit\n"); return error; } /** * hibernate_quiet_exec - Execute a function with all devices frozen. * @func: Function to execute. * @data: Data pointer to pass to @func. * * Return the @func return value or an error code if it cannot be executed. */ int hibernate_quiet_exec(int (*func)(void *data), void *data) { unsigned int sleep_flags; int error; sleep_flags = lock_system_sleep(); if (!hibernate_acquire()) { error = -EBUSY; goto unlock; } pm_prepare_console(); error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION); if (error) goto restore; error = freeze_processes(); if (error) goto exit; lock_device_hotplug(); pm_suspend_clear_flags(); error = platform_begin(true); if (error) goto thaw; error = freeze_kernel_threads(); if (error) goto thaw; error = dpm_prepare(PMSG_FREEZE); if (error) goto dpm_complete; suspend_console(); error = dpm_suspend(PMSG_FREEZE); if (error) goto dpm_resume; error = dpm_suspend_end(PMSG_FREEZE); if (error) goto dpm_resume; error = platform_pre_snapshot(true); if (error) goto skip; error = func(data); skip: platform_finish(true); dpm_resume_start(PMSG_THAW); dpm_resume: dpm_resume(PMSG_THAW); resume_console(); dpm_complete: dpm_complete(PMSG_THAW); thaw_kernel_threads(); thaw: platform_end(true); unlock_device_hotplug(); thaw_processes(); exit: pm_notifier_call_chain(PM_POST_HIBERNATION); restore: pm_restore_console(); hibernate_release(); unlock: unlock_system_sleep(sleep_flags); return error; } EXPORT_SYMBOL_GPL(hibernate_quiet_exec); static int __init find_resume_device(void) { if (!strlen(resume_file)) return -ENOENT; pm_pr_dbg("Checking hibernation image partition %s\n", resume_file); if (resume_delay) { pr_info("Waiting %dsec before reading resume device ...\n", resume_delay); ssleep(resume_delay); } /* Check if the device is there */ if (!early_lookup_bdev(resume_file, &swsusp_resume_device)) return 0; /* * Some device discovery might still be in progress; we need to wait for * this to finish. */ wait_for_device_probe(); if (resume_wait) { while (early_lookup_bdev(resume_file, &swsusp_resume_device)) msleep(10); async_synchronize_full(); } return early_lookup_bdev(resume_file, &swsusp_resume_device); } static int software_resume(void) { int error; pm_pr_dbg("Hibernation image partition %d:%d present\n", MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); pm_pr_dbg("Looking for hibernation image.\n"); mutex_lock(&system_transition_mutex); error = swsusp_check(true); if (error) goto Unlock; /* * Check if the hibernation image is compressed. If so, query for * the algorithm support. */ if (!(swsusp_header_flags & SF_NOCOMPRESS_MODE)) { if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4) strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo)); else strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo)); if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) { pr_err("%s compression is not available\n", hib_comp_algo); error = -EOPNOTSUPP; goto Unlock; } } /* The snapshot device should not be opened while we're running */ if (!hibernate_acquire()) { error = -EBUSY; swsusp_close(); goto Unlock; } pr_info("resume from hibernation\n"); pm_prepare_console(); error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE); if (error) goto Restore; pm_pr_dbg("Preparing processes for hibernation restore.\n"); error = freeze_processes(); if (error) goto Close_Finish; error = freeze_kernel_threads(); if (error) { thaw_processes(); goto Close_Finish; } error = load_image_and_restore(); thaw_processes(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); Restore: pm_restore_console(); pr_info("resume failed (%d)\n", error); hibernate_release(); /* For success case, the suspend path will release the lock */ Unlock: mutex_unlock(&system_transition_mutex); pm_pr_dbg("Hibernation image not present or could not be loaded.\n"); return error; Close_Finish: swsusp_close(); goto Finish; } /** * software_resume_initcall - Resume from a saved hibernation image. * * This routine is called as a late initcall, when all devices have been * discovered and initialized already. * * The image reading code is called to see if there is a hibernation image * available for reading. If that is the case, devices are quiesced and the * contents of memory is restored from the saved image. * * If this is successful, control reappears in the restored target kernel in * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine * attempts to recover gracefully and make the kernel return to the normal mode * of operation. */ static int __init software_resume_initcall(void) { /* * If the user said "noresume".. bail out early. */ if (noresume || !hibernation_available()) return 0; if (!swsusp_resume_device) { int error = find_resume_device(); if (error) return error; } return software_resume(); } late_initcall_sync(software_resume_initcall); static const char * const hibernation_modes[] = { [HIBERNATION_PLATFORM] = "platform", [HIBERNATION_SHUTDOWN] = "shutdown", [HIBERNATION_REBOOT] = "reboot", #ifdef CONFIG_SUSPEND [HIBERNATION_SUSPEND] = "suspend", #endif [HIBERNATION_TEST_RESUME] = "test_resume", }; /* * /sys/power/disk - Control hibernation mode. * * Hibernation can be handled in several ways. There are a few different ways * to put the system into the sleep state: using the platform driver (e.g. ACPI * or other hibernation_ops), powering it off or rebooting it (for testing * mostly). * * The sysfs file /sys/power/disk provides an interface for selecting the * hibernation mode to use. Reading from this file causes the available modes * to be printed. There are 3 modes that can be supported: * * 'platform' * 'shutdown' * 'reboot' * * If a platform hibernation driver is in use, 'platform' will be supported * and will be used by default. Otherwise, 'shutdown' will be used by default. * The selected option (i.e. the one corresponding to the current value of * hibernation_mode) is enclosed by a square bracket. * * To select a given hibernation mode it is necessary to write the mode's * string representation (as returned by reading from /sys/power/disk) back * into /sys/power/disk. */ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { ssize_t count = 0; int i; if (!hibernation_available()) return sysfs_emit(buf, "[disabled]\n"); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (!hibernation_modes[i]) continue; switch (i) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: #ifdef CONFIG_SUSPEND case HIBERNATION_SUSPEND: #endif case HIBERNATION_TEST_RESUME: break; case HIBERNATION_PLATFORM: if (hibernation_ops) break; /* not a valid mode, continue with loop */ continue; } if (i == hibernation_mode) count += sysfs_emit_at(buf, count, "[%s] ", hibernation_modes[i]); else count += sysfs_emit_at(buf, count, "%s ", hibernation_modes[i]); } /* Convert the last space to a newline if needed. */ if (count > 0) buf[count - 1] = '\n'; return count; } static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { int mode = HIBERNATION_INVALID; unsigned int sleep_flags; int error = 0; int len; char *p; int i; if (!hibernation_available()) return -EPERM; p = memchr(buf, '\n', n); len = p ? p - buf : n; sleep_flags = lock_system_sleep(); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (len == strlen(hibernation_modes[i]) && !strncmp(buf, hibernation_modes[i], len)) { mode = i; break; } } if (mode != HIBERNATION_INVALID) { switch (mode) { case HIBERNATION_SHUTDOWN: case HIBERNATION_REBOOT: #ifdef CONFIG_SUSPEND case HIBERNATION_SUSPEND: #endif case HIBERNATION_TEST_RESUME: hibernation_mode = mode; break; case HIBERNATION_PLATFORM: if (hibernation_ops) hibernation_mode = mode; else error = -EINVAL; } } else error = -EINVAL; if (!error) pm_pr_dbg("Hibernation mode set to '%s'\n", hibernation_modes[mode]); unlock_system_sleep(sleep_flags); return error ? error : n; } power_attr(disk); static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "%d:%d\n", MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); } static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { unsigned int sleep_flags; int len = n; char *name; dev_t dev; int error; if (!hibernation_available()) return n; if (len && buf[len-1] == '\n') len--; name = kstrndup(buf, len, GFP_KERNEL); if (!name) return -ENOMEM; error = lookup_bdev(name, &dev); if (error) { unsigned maj, min, offset; char *p, dummy; error = 0; if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 || sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) { dev = MKDEV(maj, min); if (maj != MAJOR(dev) || min != MINOR(dev)) error = -EINVAL; } else { dev = new_decode_dev(simple_strtoul(name, &p, 16)); if (*p) error = -EINVAL; } } kfree(name); if (error) return error; sleep_flags = lock_system_sleep(); swsusp_resume_device = dev; unlock_system_sleep(sleep_flags); pm_pr_dbg("Configured hibernation resume from disk to %u\n", swsusp_resume_device); noresume = 0; software_resume(); return n; } power_attr(resume); static ssize_t resume_offset_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "%llu\n", (unsigned long long)swsusp_resume_block); } static ssize_t resume_offset_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { unsigned long long offset; int rc; rc = kstrtoull(buf, 0, &offset); if (rc) return rc; swsusp_resume_block = offset; return n; } power_attr(resume_offset); static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "%lu\n", image_size); } static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { unsigned long size; if (sscanf(buf, "%lu", &size) == 1) { image_size = size; return n; } return -EINVAL; } power_attr(image_size); static ssize_t reserved_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { return sysfs_emit(buf, "%lu\n", reserved_size); } static ssize_t reserved_size_store(struct kobject *kobj, struct kobj_attribute *attr, const char *buf, size_t n) { unsigned long size; if (sscanf(buf, "%lu", &size) == 1) { reserved_size = size; return n; } return -EINVAL; } power_attr(reserved_size); static struct attribute *g[] = { &disk_attr.attr, &resume_offset_attr.attr, &resume_attr.attr, &image_size_attr.attr, &reserved_size_attr.attr, NULL, }; static const struct attribute_group attr_group = { .attrs = g, }; static int __init pm_disk_init(void) { return sysfs_create_group(power_kobj, &attr_group); } core_initcall(pm_disk_init); static int __init resume_setup(char *str) { if (noresume) return 1; strscpy(resume_file, str); return 1; } static int __init resume_offset_setup(char *str) { unsigned long long offset; if (noresume) return 1; if (sscanf(str, "%llu", &offset) == 1) swsusp_resume_block = offset; return 1; } static int __init hibernate_setup(char *str) { if (!strncmp(str, "noresume", 8)) { noresume = 1; } else if (!strncmp(str, "nocompress", 10)) { nocompress = 1; } else if (!strncmp(str, "no", 2)) { noresume = 1; nohibernate = 1; } else if (IS_ENABLED(CONFIG_STRICT_KERNEL_RWX) && !strncmp(str, "protect_image", 13)) { enable_restore_image_protection(); } return 1; } static int __init noresume_setup(char *str) { noresume = 1; return 1; } static int __init resumewait_setup(char *str) { resume_wait = 1; return 1; } static int __init resumedelay_setup(char *str) { int rc = kstrtouint(str, 0, &resume_delay); if (rc) pr_warn("resumedelay: bad option string '%s'\n", str); return 1; } static int __init nohibernate_setup(char *str) { noresume = 1; nohibernate = 1; return 1; } static const char * const comp_alg_enabled[] = { #if IS_ENABLED(CONFIG_CRYPTO_LZO) COMPRESSION_ALGO_LZO, #endif #if IS_ENABLED(CONFIG_CRYPTO_LZ4) COMPRESSION_ALGO_LZ4, #endif }; static int hibernate_compressor_param_set(const char *compressor, const struct kernel_param *kp) { unsigned int sleep_flags; int index, ret; sleep_flags = lock_system_sleep(); index = sysfs_match_string(comp_alg_enabled, compressor); if (index >= 0) { ret = param_set_copystring(comp_alg_enabled[index], kp); if (!ret) strscpy(hib_comp_algo, comp_alg_enabled[index], sizeof(hib_comp_algo)); } else { ret = index; } unlock_system_sleep(sleep_flags); if (ret) pr_debug("Cannot set specified compressor %s\n", compressor); return ret; } static const struct kernel_param_ops hibernate_compressor_param_ops = { .set = hibernate_compressor_param_set, .get = param_get_string, }; static struct kparam_string hibernate_compressor_param_string = { .maxlen = sizeof(hibernate_compressor), .string = hibernate_compressor, }; module_param_cb(compressor, &hibernate_compressor_param_ops, &hibernate_compressor_param_string, 0644); MODULE_PARM_DESC(compressor, "Compression algorithm to be used with hibernation"); __setup("noresume", noresume_setup); __setup("resume_offset=", resume_offset_setup); __setup("resume=", resume_setup); __setup("hibernate=", hibernate_setup); __setup("resumewait", resumewait_setup); __setup("resumedelay=", resumedelay_setup); __setup("nohibernate", nohibernate_setup);