diff options
Diffstat (limited to 'kernel/power/hibernate.c')
| -rw-r--r-- | kernel/power/hibernate.c | 470 |
1 files changed, 337 insertions, 133 deletions
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index e6af502c2fd7..af8d07bafe02 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -11,6 +11,8 @@ #define pr_fmt(fmt) "PM: hibernation: " fmt +#include <crypto/acompress.h> +#include <linux/blkdev.h> #include <linux/export.h> #include <linux/suspend.h> #include <linux/reboot.h> @@ -28,7 +30,6 @@ #include <linux/gfp.h> #include <linux/syscore_ops.h> #include <linux/ctype.h> -#include <linux/genhd.h> #include <linux/ktime.h> #include <linux/security.h> #include <linux/secretmem.h> @@ -47,6 +48,15 @@ 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, @@ -70,6 +80,17 @@ static const struct platform_hibernation_ops *hibernation_ops; static atomic_t hibernate_atomic = ATOMIC_INIT(1); +#ifdef CONFIG_SUSPEND +/** + * pm_hibernation_mode_is_suspend - Check if hibernation has been set to suspend + */ +bool pm_hibernation_mode_is_suspend(void) +{ + return hibernation_mode == HIBERNATION_SUSPEND; +} +EXPORT_SYMBOL_GPL(pm_hibernation_mode_is_suspend); +#endif + bool hibernate_acquire(void) { return atomic_add_unless(&hibernate_atomic, -1, 0); @@ -80,11 +101,16 @@ void hibernate_release(void) atomic_inc(&hibernate_atomic); } +bool hibernation_in_progress(void) +{ + return !atomic_read(&hibernate_atomic); +} + bool hibernation_available(void) { return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION) && - !secretmem_active(); + !secretmem_active() && !cxl_mem_active(); } /** @@ -93,20 +119,24 @@ bool hibernation_available(void) */ 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; } - lock_system_sleep(); + + 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(); + unlock_system_sleep(sleep_flags); } EXPORT_SYMBOL_GPL(hibernation_set_ops); @@ -119,10 +149,15 @@ bool system_entering_hibernation(void) EXPORT_SYMBOL(system_entering_hibernation); #ifdef CONFIG_PM_DEBUG +static unsigned int pm_test_delay = 5; +module_param(pm_test_delay, uint, 0644); +MODULE_PARM_DESC(pm_test_delay, + "Number of seconds to wait before resuming from hibernation test"); static void hibernation_debug_sleep(void) { - pr_info("debug: Waiting for 5 seconds.\n"); - mdelay(5000); + pr_info("hibernation debug: Waiting for %d second(s).\n", + pm_test_delay); + mdelay(pm_test_delay * 1000); } static int hibernation_test(int level) @@ -357,6 +392,23 @@ static int create_image(int platform_mode) return error; } +static void shrink_shmem_memory(void) +{ + struct sysinfo info; + unsigned long nr_shmem_pages, nr_freed_pages; + + si_meminfo(&info); + nr_shmem_pages = info.sharedram; /* current page count used for shmem */ + /* + * The intent is to reclaim all shmem pages. Though shrink_all_memory() can + * only reclaim about half of them, it's enough for creating the hibernation + * image. + */ + nr_freed_pages = shrink_all_memory(nr_shmem_pages); + pr_debug("requested to reclaim %lu shmem pages, actually freed %lu pages\n", + nr_shmem_pages, nr_freed_pages); +} + /** * hibernation_snapshot - Quiesce devices and create a hibernation image. * @platform_mode: If set, use platform driver to prepare for the transition. @@ -398,7 +450,16 @@ int hibernation_snapshot(int platform_mode) goto Thaw; } - suspend_console(); + /* + * Device drivers may move lots of data to shmem in dpm_prepare(). The shmem + * pages will use lots of system memory, causing hibernation image creation + * fail due to insufficient free memory. + * This call is to force flush the shmem pages to swap disk and reclaim + * the system memory so that image creation can succeed. + */ + shrink_shmem_memory(); + + console_suspend_all(); pm_restrict_gfp_mask(); error = dpm_suspend(PMSG_FREEZE); @@ -424,7 +485,7 @@ int hibernation_snapshot(int platform_mode) if (error || !in_suspend) pm_restore_gfp_mask(); - resume_console(); + console_resume_all(); dpm_complete(msg); Close: @@ -534,8 +595,7 @@ int hibernation_restore(int platform_mode) int error; pm_prepare_console(); - suspend_console(); - pm_restrict_gfp_mask(); + console_suspend_all(); error = dpm_suspend_start(PMSG_QUIESCE); if (!error) { error = resume_target_kernel(platform_mode); @@ -547,8 +607,7 @@ int hibernation_restore(int platform_mode) BUG_ON(!error); } dpm_resume_end(PMSG_RECOVER); - pm_restore_gfp_mask(); - resume_console(); + console_resume_all(); pm_restore_console(); return error; } @@ -573,7 +632,7 @@ int hibernation_platform_enter(void) goto Close; entering_platform_hibernation = true; - suspend_console(); + console_suspend_all(); error = dpm_suspend_start(PMSG_HIBERNATE); if (error) { if (hibernation_ops->recover) @@ -595,7 +654,11 @@ int hibernation_platform_enter(void) local_irq_disable(); system_state = SYSTEM_SUSPEND; - syscore_suspend(); + + error = syscore_suspend(); + if (error) + goto Enable_irqs; + if (pm_wakeup_pending()) { error = -EAGAIN; goto Power_up; @@ -607,6 +670,7 @@ int hibernation_platform_enter(void) Power_up: syscore_resume(); + Enable_irqs: system_state = SYSTEM_RUNNING; local_irq_enable(); @@ -621,7 +685,7 @@ int hibernation_platform_enter(void) Resume_devices: entering_platform_hibernation = false; dpm_resume_end(PMSG_RESTORE); - resume_console(); + console_resume_all(); Close: hibernation_ops->end(); @@ -638,23 +702,16 @@ int hibernation_platform_enter(void) */ static void power_down(void) { -#ifdef CONFIG_SUSPEND int error; +#ifdef CONFIG_SUSPEND if (hibernation_mode == HIBERNATION_SUSPEND) { - error = suspend_devices_and_enter(PM_SUSPEND_MEM); - 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"); + error = suspend_devices_and_enter(mem_sleep_current); + if (!error) + goto exit; - return; - } + hibernation_mode = hibernation_ops ? HIBERNATION_PLATFORM : + HIBERNATION_SHUTDOWN; } #endif @@ -663,11 +720,19 @@ static void power_down(void) kernel_restart(NULL); break; case HIBERNATION_PLATFORM: - hibernation_platform_enter(); + error = hibernation_platform_enter(); + if (error == -EAGAIN || error == -EBUSY) { + events_check_enabled = false; + pr_info("Wakeup event detected during hibernation, rolling back.\n"); + goto exit; + } fallthrough; case HIBERNATION_SHUTDOWN: - if (pm_power_off) + if (kernel_can_power_off()) { + entering_platform_hibernation = true; kernel_power_off(); + entering_platform_hibernation = false; + } break; } kernel_halt(); @@ -678,6 +743,12 @@ static void power_down(void) pr_crit("Power down manually\n"); while (1) cpu_relax(); + +exit: + /* Restore swap signature. */ + error = swsusp_unmark(); + if (error) + pr_err("Swap will be unusable! Try swapon -a.\n"); } static int load_image_and_restore(void) @@ -689,11 +760,13 @@ static int load_image_and_restore(void) lock_device_hotplug(); error = create_basic_memory_bitmaps(); - if (error) + if (error) { + swsusp_close(); goto Unlock; + } error = swsusp_read(&flags); - swsusp_close(FMODE_READ | FMODE_EXCL); + swsusp_close(); if (!error) error = hibernation_restore(flags & SF_PLATFORM_MODE); @@ -706,12 +779,16 @@ static int load_image_and_restore(void) 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()) { @@ -719,7 +796,18 @@ int hibernate(void) return -EPERM; } - lock_system_sleep(); + /* + * Query for the compression algorithm support if compression is enabled. + */ + if (!nocompress) { + strscpy(hib_comp_algo, hibernate_compressor); + if (!crypto_has_acomp(hib_comp_algo, 0, CRYPTO_ALG_ASYNC)) { + 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; @@ -732,7 +820,11 @@ int hibernate(void) if (error) goto Restore; - ksys_sync_helper(); + error = pm_sleep_fs_sync(); + if (error) + goto Notify; + + filesystems_freeze(filesystem_freeze_enabled); error = freeze_processes(); if (error) @@ -753,11 +845,24 @@ int hibernate(void) if (hibernation_mode == HIBERNATION_PLATFORM) flags |= SF_PLATFORM_MODE; - if (nocompress) + if (nocompress) { flags |= SF_NOCOMPRESS_MODE; - else + } 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(); @@ -779,7 +884,7 @@ int hibernate(void) unlock_device_hotplug(); if (snapshot_test) { pm_pr_dbg("Checking hibernation image\n"); - error = swsusp_check(); + error = swsusp_check(false); if (!error) error = load_image_and_restore(); } @@ -788,12 +893,14 @@ int hibernate(void) /* Don't bother checking whether freezer_test_done is true */ freezer_test_done = false; Exit: + filesystems_thaw(); + Notify: pm_notifier_call_chain(PM_POST_HIBERNATION); Restore: pm_restore_console(); hibernate_release(); Unlock: - unlock_system_sleep(); + unlock_system_sleep(sleep_flags); pr_info("hibernation exit\n"); return error; @@ -808,9 +915,10 @@ int hibernate(void) */ int hibernate_quiet_exec(int (*func)(void *data), void *data) { + unsigned int sleep_flags; int error; - lock_system_sleep(); + sleep_flags = lock_system_sleep(); if (!hibernate_acquire()) { error = -EBUSY; @@ -823,6 +931,8 @@ int hibernate_quiet_exec(int (*func)(void *data), void *data) if (error) goto restore; + filesystems_freeze(filesystem_freeze_enabled); + error = freeze_processes(); if (error) goto exit; @@ -843,7 +953,7 @@ int hibernate_quiet_exec(int (*func)(void *data), void *data) if (error) goto dpm_complete; - suspend_console(); + console_suspend_all(); error = dpm_suspend(PMSG_FREEZE); if (error) @@ -867,7 +977,7 @@ skip: dpm_resume: dpm_resume(PMSG_THAW); - resume_console(); + console_resume_all(); dpm_complete: dpm_complete(PMSG_THAW); @@ -882,6 +992,7 @@ thaw: thaw_processes(); exit: + filesystems_thaw(); pm_notifier_call_chain(PM_POST_HIBERNATION); restore: @@ -890,56 +1001,16 @@ restore: hibernate_release(); unlock: - unlock_system_sleep(); + unlock_system_sleep(sleep_flags); return error; } EXPORT_SYMBOL_GPL(hibernate_quiet_exec); -/** - * software_resume - 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 software_resume(void) +static int __init find_resume_device(void) { - int error; - - /* - * If the user said "noresume".. bail out early. - */ - if (noresume || !hibernation_available()) - return 0; - - /* - * name_to_dev_t() below takes a sysfs buffer mutex when sysfs - * is configured into the kernel. Since the regular hibernate - * trigger path is via sysfs which takes a buffer mutex before - * calling hibernate functions (which take system_transition_mutex) - * this can cause lockdep to complain about a possible ABBA deadlock - * which cannot happen since we're in the boot code here and - * sysfs can't be invoked yet. Therefore, we use a subclass - * here to avoid lockdep complaining. - */ - mutex_lock_nested(&system_transition_mutex, SINGLE_DEPTH_NESTING); - - if (swsusp_resume_device) - goto Check_image; - - if (!strlen(resume_file)) { - error = -ENOENT; - goto Unlock; - } + if (!strlen(resume_file)) + return -ENOENT; pm_pr_dbg("Checking hibernation image partition %s\n", resume_file); @@ -950,40 +1021,57 @@ static int software_resume(void) } /* Check if the device is there */ - swsusp_resume_device = name_to_dev_t(resume_file); - if (!swsusp_resume_device) { - /* - * Some device discovery might still be in progress; we need - * to wait for this to finish. - */ - wait_for_device_probe(); - - if (resume_wait) { - while ((swsusp_resume_device = name_to_dev_t(resume_file)) == 0) - msleep(10); - async_synchronize_full(); - } + if (!early_lookup_bdev(resume_file, &swsusp_resume_device)) + return 0; - swsusp_resume_device = name_to_dev_t(resume_file); - if (!swsusp_resume_device) { - error = -ENODEV; - goto Unlock; - } + /* + * 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(); } - Check_image: + 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"); - error = swsusp_check(); + + 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); + else + strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO); + if (!crypto_has_acomp(hib_comp_algo, 0, CRYPTO_ALG_ASYNC)) { + 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(FMODE_READ | FMODE_EXCL); + swsusp_close(); goto Unlock; } @@ -993,19 +1081,25 @@ static int software_resume(void) if (error) goto Restore; + filesystems_freeze(filesystem_freeze_enabled); + pm_pr_dbg("Preparing processes for hibernation restore.\n"); error = freeze_processes(); - if (error) + if (error) { + filesystems_thaw(); goto Close_Finish; + } error = freeze_kernel_threads(); if (error) { thaw_processes(); + filesystems_thaw(); goto Close_Finish; } error = load_image_and_restore(); thaw_processes(); + filesystems_thaw(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); Restore: @@ -1018,11 +1112,43 @@ static int software_resume(void) pm_pr_dbg("Hibernation image not present or could not be loaded.\n"); return error; Close_Finish: - swsusp_close(FMODE_READ | FMODE_EXCL); + swsusp_close(); goto Finish; } -late_initcall_sync(software_resume); +/** + * 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[] = { @@ -1064,11 +1190,11 @@ static const char * const hibernation_modes[] = { static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { + ssize_t count = 0; int i; - char *start = buf; if (!hibernation_available()) - return sprintf(buf, "[disabled]\n"); + return sysfs_emit(buf, "[disabled]\n"); for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (!hibernation_modes[i]) @@ -1088,22 +1214,27 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, continue; } if (i == hibernation_mode) - buf += sprintf(buf, "[%s] ", hibernation_modes[i]); + count += sysfs_emit_at(buf, count, "[%s] ", hibernation_modes[i]); else - buf += sprintf(buf, "%s ", hibernation_modes[i]); + count += sysfs_emit_at(buf, count, "%s ", hibernation_modes[i]); } - buf += sprintf(buf, "\n"); - return buf-start; + + /* 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 i; int len; char *p; - int mode = HIBERNATION_INVALID; + int i; if (!hibernation_available()) return -EPERM; @@ -1111,7 +1242,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, p = memchr(buf, '\n', n); len = p ? p - buf : n; - lock_system_sleep(); + 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)) { @@ -1141,7 +1272,7 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, if (!error) pm_pr_dbg("Hibernation mode set to '%s'\n", hibernation_modes[mode]); - unlock_system_sleep(); + unlock_system_sleep(sleep_flags); return error ? error : n; } @@ -1150,16 +1281,21 @@ power_attr(disk); static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device), - MINOR(swsusp_resume_device)); + 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) { - dev_t res; + 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--; @@ -1167,14 +1303,32 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr, if (!name) return -ENOMEM; - res = name_to_dev_t(name); + 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 (!res) - return -EINVAL; + if (error) + return error; + + sleep_flags = lock_system_sleep(); + swsusp_resume_device = dev; + unlock_system_sleep(sleep_flags); - lock_system_sleep(); - swsusp_resume_device = res; - unlock_system_sleep(); pm_pr_dbg("Configured hibernation resume from disk to %u\n", swsusp_resume_device); noresume = 0; @@ -1187,7 +1341,7 @@ power_attr(resume); static ssize_t resume_offset_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%llu\n", (unsigned long long)swsusp_resume_block); + return sysfs_emit(buf, "%llu\n", (unsigned long long)swsusp_resume_block); } static ssize_t resume_offset_store(struct kobject *kobj, @@ -1210,7 +1364,7 @@ power_attr(resume_offset); static ssize_t image_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%lu\n", image_size); + return sysfs_emit(buf, "%lu\n", image_size); } static ssize_t image_size_store(struct kobject *kobj, struct kobj_attribute *attr, @@ -1231,7 +1385,7 @@ power_attr(image_size); static ssize_t reserved_size_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { - return sprintf(buf, "%lu\n", reserved_size); + return sysfs_emit(buf, "%lu\n", reserved_size); } static ssize_t reserved_size_store(struct kobject *kobj, @@ -1278,7 +1432,7 @@ static int __init resume_setup(char *str) if (noresume) return 1; - strncpy(resume_file, str, 255); + strscpy(resume_file, str); return 1; } @@ -1328,7 +1482,7 @@ static int __init resumedelay_setup(char *str) int rc = kstrtouint(str, 0, &resume_delay); if (rc) - return rc; + pr_warn("resumedelay: bad option string '%s'\n", str); return 1; } @@ -1339,6 +1493,56 @@ static int __init nohibernate_setup(char *str) 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) +{ + int index, ret; + + if (!mutex_trylock(&system_transition_mutex)) + return -EBUSY; + + 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]); + } else { + ret = index; + } + + mutex_unlock(&system_transition_mutex); + + 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); |