From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- kernel/power/disk.c | 431 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 431 insertions(+) create mode 100644 kernel/power/disk.c (limited to 'kernel/power/disk.c') diff --git a/kernel/power/disk.c b/kernel/power/disk.c new file mode 100644 index 0000000..02b6764 --- /dev/null +++ b/kernel/power/disk.c @@ -0,0 +1,431 @@ +/* + * kernel/power/disk.c - Suspend-to-disk support. + * + * Copyright (c) 2003 Patrick Mochel + * Copyright (c) 2003 Open Source Development Lab + * Copyright (c) 2004 Pavel Machek + * + * This file is released under the GPLv2. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include "power.h" + + +extern suspend_disk_method_t pm_disk_mode; +extern struct pm_ops * pm_ops; + +extern int swsusp_suspend(void); +extern int swsusp_write(void); +extern int swsusp_check(void); +extern int swsusp_read(void); +extern void swsusp_close(void); +extern int swsusp_resume(void); +extern int swsusp_free(void); + + +static int noresume = 0; +char resume_file[256] = CONFIG_PM_STD_PARTITION; +dev_t swsusp_resume_device; + +/** + * power_down - Shut machine down for hibernate. + * @mode: Suspend-to-disk mode + * + * Use the platform driver, if configured so, and return gracefully if it + * fails. + * Otherwise, try to power off and reboot. If they fail, halt the machine, + * there ain't no turning back. + */ + +static void power_down(suspend_disk_method_t mode) +{ + unsigned long flags; + int error = 0; + + local_irq_save(flags); + switch(mode) { + case PM_DISK_PLATFORM: + device_shutdown(); + error = pm_ops->enter(PM_SUSPEND_DISK); + break; + case PM_DISK_SHUTDOWN: + printk("Powering off system\n"); + device_shutdown(); + machine_power_off(); + break; + case PM_DISK_REBOOT: + device_shutdown(); + machine_restart(NULL); + break; + } + machine_halt(); + /* Valid image is on the disk, if we continue we risk serious data corruption + after resume. */ + printk(KERN_CRIT "Please power me down manually\n"); + while(1); +} + + +static int in_suspend __nosavedata = 0; + + +/** + * free_some_memory - Try to free as much memory as possible + * + * ... but do not OOM-kill anyone + * + * Notice: all userland should be stopped at this point, or + * livelock is possible. + */ + +static void free_some_memory(void) +{ + unsigned int i = 0; + unsigned int tmp; + unsigned long pages = 0; + char *p = "-\\|/"; + + printk("Freeing memory... "); + while ((tmp = shrink_all_memory(10000))) { + pages += tmp; + printk("\b%c", p[i]); + i++; + if (i > 3) + i = 0; + } + printk("\bdone (%li pages freed)\n", pages); +} + + +static inline void platform_finish(void) +{ + if (pm_disk_mode == PM_DISK_PLATFORM) { + if (pm_ops && pm_ops->finish) + pm_ops->finish(PM_SUSPEND_DISK); + } +} + +static void finish(void) +{ + device_resume(); + platform_finish(); + enable_nonboot_cpus(); + thaw_processes(); + pm_restore_console(); +} + + +static int prepare_processes(void) +{ + int error; + + pm_prepare_console(); + + sys_sync(); + + if (freeze_processes()) { + error = -EBUSY; + return error; + } + + if (pm_disk_mode == PM_DISK_PLATFORM) { + if (pm_ops && pm_ops->prepare) { + if ((error = pm_ops->prepare(PM_SUSPEND_DISK))) + return error; + } + } + + /* Free memory before shutting down devices. */ + free_some_memory(); + + return 0; +} + +static void unprepare_processes(void) +{ + enable_nonboot_cpus(); + thaw_processes(); + pm_restore_console(); +} + +static int prepare_devices(void) +{ + int error; + + disable_nonboot_cpus(); + if ((error = device_suspend(PMSG_FREEZE))) { + printk("Some devices failed to suspend\n"); + platform_finish(); + enable_nonboot_cpus(); + return error; + } + + return 0; +} + +/** + * pm_suspend_disk - The granpappy of power management. + * + * If we're going through the firmware, then get it over with quickly. + * + * If not, then call swsusp to do its thing, then figure out how + * to power down the system. + */ + +int pm_suspend_disk(void) +{ + int error; + + error = prepare_processes(); + if (!error) { + error = prepare_devices(); + } + + if (error) { + unprepare_processes(); + return error; + } + + pr_debug("PM: Attempting to suspend to disk.\n"); + if (pm_disk_mode == PM_DISK_FIRMWARE) + return pm_ops->enter(PM_SUSPEND_DISK); + + pr_debug("PM: snapshotting memory.\n"); + in_suspend = 1; + if ((error = swsusp_suspend())) + goto Done; + + if (in_suspend) { + pr_debug("PM: writing image.\n"); + error = swsusp_write(); + if (!error) + power_down(pm_disk_mode); + } else + pr_debug("PM: Image restored successfully.\n"); + swsusp_free(); + Done: + finish(); + return error; +} + + +/** + * software_resume - Resume from a saved image. + * + * Called as a late_initcall (so all devices are discovered and + * initialized), we call swsusp to see if we have a saved image or not. + * If so, we quiesce devices, the restore the saved image. We will + * return above (in pm_suspend_disk() ) if everything goes well. + * Otherwise, we fail gracefully and return to the normally + * scheduled program. + * + */ + +static int software_resume(void) +{ + int error; + + if (noresume) { + /** + * FIXME: If noresume is specified, we need to find the partition + * and reset it back to normal swap space. + */ + return 0; + } + + pr_debug("PM: Checking swsusp image.\n"); + + if ((error = swsusp_check())) + goto Done; + + pr_debug("PM: Preparing processes for restore.\n"); + + if ((error = prepare_processes())) { + swsusp_close(); + goto Cleanup; + } + + pr_debug("PM: Reading swsusp image.\n"); + + if ((error = swsusp_read())) + goto Cleanup; + + pr_debug("PM: Preparing devices for restore.\n"); + + if ((error = prepare_devices())) + goto Free; + + mb(); + + pr_debug("PM: Restoring saved image.\n"); + swsusp_resume(); + pr_debug("PM: Restore failed, recovering.n"); + finish(); + Free: + swsusp_free(); + Cleanup: + unprepare_processes(); + Done: + pr_debug("PM: Resume from disk failed.\n"); + return 0; +} + +late_initcall(software_resume); + + +static char * pm_disk_modes[] = { + [PM_DISK_FIRMWARE] = "firmware", + [PM_DISK_PLATFORM] = "platform", + [PM_DISK_SHUTDOWN] = "shutdown", + [PM_DISK_REBOOT] = "reboot", +}; + +/** + * disk - Control suspend-to-disk mode + * + * Suspend-to-disk can be handled in several ways. The greatest + * distinction is who writes memory to disk - the firmware or the OS. + * If the firmware does it, we assume that it also handles suspending + * the system. + * If the OS does it, then we have three options for putting the system + * to sleep - using the platform driver (e.g. ACPI or other PM registers), + * powering off the system or rebooting the system (for testing). + * + * The system will support either 'firmware' or 'platform', and that is + * known a priori (and encoded in pm_ops). But, the user may choose + * 'shutdown' or 'reboot' as alternatives. + * + * show() will display what the mode is currently set to. + * store() will accept one of + * + * 'firmware' + * 'platform' + * 'shutdown' + * 'reboot' + * + * It will only change to 'firmware' or 'platform' if the system + * supports it (as determined from pm_ops->pm_disk_mode). + */ + +static ssize_t disk_show(struct subsystem * subsys, char * buf) +{ + return sprintf(buf, "%s\n", pm_disk_modes[pm_disk_mode]); +} + + +static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n) +{ + int error = 0; + int i; + int len; + char *p; + suspend_disk_method_t mode = 0; + + p = memchr(buf, '\n', n); + len = p ? p - buf : n; + + down(&pm_sem); + for (i = PM_DISK_FIRMWARE; i < PM_DISK_MAX; i++) { + if (!strncmp(buf, pm_disk_modes[i], len)) { + mode = i; + break; + } + } + if (mode) { + if (mode == PM_DISK_SHUTDOWN || mode == PM_DISK_REBOOT) + pm_disk_mode = mode; + else { + if (pm_ops && pm_ops->enter && + (mode == pm_ops->pm_disk_mode)) + pm_disk_mode = mode; + else + error = -EINVAL; + } + } else + error = -EINVAL; + + pr_debug("PM: suspend-to-disk mode set to '%s'\n", + pm_disk_modes[mode]); + up(&pm_sem); + return error ? error : n; +} + +power_attr(disk); + +static ssize_t resume_show(struct subsystem * subsys, char *buf) +{ + return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device), + MINOR(swsusp_resume_device)); +} + +static ssize_t resume_store(struct subsystem * subsys, const char * buf, size_t n) +{ + int len; + char *p; + unsigned int maj, min; + int error = -EINVAL; + dev_t res; + + p = memchr(buf, '\n', n); + len = p ? p - buf : n; + + if (sscanf(buf, "%u:%u", &maj, &min) == 2) { + res = MKDEV(maj,min); + if (maj == MAJOR(res) && min == MINOR(res)) { + swsusp_resume_device = res; + printk("Attempting manual resume\n"); + noresume = 0; + software_resume(); + } + } + + return error >= 0 ? n : error; +} + +power_attr(resume); + +static struct attribute * g[] = { + &disk_attr.attr, + &resume_attr.attr, + NULL, +}; + + +static struct attribute_group attr_group = { + .attrs = g, +}; + + +static int __init pm_disk_init(void) +{ + return sysfs_create_group(&power_subsys.kset.kobj,&attr_group); +} + +core_initcall(pm_disk_init); + + +static int __init resume_setup(char *str) +{ + if (noresume) + return 1; + + strncpy( resume_file, str, 255 ); + return 1; +} + +static int __init noresume_setup(char *str) +{ + noresume = 1; + return 1; +} + +__setup("noresume", noresume_setup); +__setup("resume=", resume_setup); -- cgit v1.1