From: Pavel Machek From: When using a fully modularized kernel it is necessary to activate resume manually as the device node might not be available during kernel init. This patch implements a new sysfs attribute '/sys/power/resume' which allows for manual activation of software resume. When read from it prints the configured resume device in 'major:minor' format. When written to it expects a device in 'major:minor' format. This device is then checked for a suspended image and resume is started if a valid image is found. The original functionality is left in place. It should be used from initramfs, or with care. Signed-off-by: Hannes Reinecke Signed-off-by: Pavel Machek Signed-off-by: Andrew Morton --- 25-akpm/include/linux/suspend.h | 2 25-akpm/init/do_mounts.c | 4 - 25-akpm/kernel/power/disk.c | 99 ++++++++++++++++++++++++++++++++------- 25-akpm/kernel/power/swsusp.c | 101 +++++++++++++++++++++++++++++----------- 4 files changed, 161 insertions(+), 45 deletions(-) diff -puN include/linux/suspend.h~swsusp-enable-resume-from-initrd include/linux/suspend.h --- 25/include/linux/suspend.h~swsusp-enable-resume-from-initrd 2005-03-09 16:43:14.000000000 -0800 +++ 25-akpm/include/linux/suspend.h 2005-03-09 16:43:14.000000000 -0800 @@ -35,6 +35,8 @@ typedef struct pbe { #define SUSPEND_PD_PAGES(x) (((x)*sizeof(struct pbe))/PAGE_SIZE+1) + +extern dev_t swsusp_resume_device; /* mm/vmscan.c */ extern int shrink_mem(void); diff -puN init/do_mounts.c~swsusp-enable-resume-from-initrd init/do_mounts.c --- 25/init/do_mounts.c~swsusp-enable-resume-from-initrd 2005-03-09 16:43:14.000000000 -0800 +++ 25-akpm/init/do_mounts.c 2005-03-09 16:43:14.000000000 -0800 @@ -53,7 +53,7 @@ static int __init readwrite(char *str) __setup("ro", readonly); __setup("rw", readwrite); -static dev_t __init try_name(char *name, int part) +static dev_t try_name(char *name, int part) { char path[64]; char buf[32]; @@ -135,7 +135,7 @@ fail: * is mounted on rootfs /sys. */ -dev_t __init name_to_dev_t(char *name) +dev_t name_to_dev_t(char *name) { char s[32]; char *p; diff -puN kernel/power/disk.c~swsusp-enable-resume-from-initrd kernel/power/disk.c --- 25/kernel/power/disk.c~swsusp-enable-resume-from-initrd 2005-03-09 16:43:14.000000000 -0800 +++ 25-akpm/kernel/power/disk.c 2005-03-09 16:43:14.000000000 -0800 @@ -16,7 +16,6 @@ #include #include #include -#include #include "power.h" @@ -25,13 +24,16 @@ 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. @@ -121,45 +123,54 @@ static void finish(void) } -static int prepare(void) +static int prepare_processes(void) { int error; pm_prepare_console(); sys_sync(); + if (freeze_processes()) { error = -EBUSY; - goto Thaw; + return error; } if (pm_disk_mode == PM_DISK_PLATFORM) { if (pm_ops && pm_ops->prepare) { if ((error = pm_ops->prepare(PM_SUSPEND_DISK))) - goto Thaw; + 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"); - goto Finish; + platform_finish(); + enable_nonboot_cpus(); + return error; } return 0; - Finish: - platform_finish(); - Thaw: - enable_nonboot_cpus(); - thaw_processes(); - pm_restore_console(); - return error; } - /** * pm_suspend_disk - The granpappy of power management. * @@ -173,8 +184,15 @@ int pm_suspend_disk(void) { int error; - if ((error = prepare())) + 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) @@ -223,14 +241,26 @@ static int software_resume(void) 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 Done; + goto Cleanup; - pr_debug("PM: Preparing system for restore.\n"); + pr_debug("PM: Preparing devices for restore.\n"); - if ((error = prepare())) + if ((error = prepare_devices())) goto Free; mb(); @@ -241,6 +271,8 @@ static int software_resume(void) finish(); Free: swsusp_free(); + Cleanup: + unprepare_processes(); Done: pr_debug("PM: Resume from disk failed.\n"); return 0; @@ -328,8 +360,41 @@ static ssize_t disk_store(struct subsyst 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, }; diff -puN kernel/power/swsusp.c~swsusp-enable-resume-from-initrd kernel/power/swsusp.c --- 25/kernel/power/swsusp.c~swsusp-enable-resume-from-initrd 2005-03-09 16:43:14.000000000 -0800 +++ 25-akpm/kernel/power/swsusp.c 2005-03-09 16:43:14.000000000 -0800 @@ -79,7 +79,7 @@ extern const void __nosave_begin, __nosa static int nr_copy_pages_check; extern char resume_file[]; -static dev_t resume_device; + /* Local variables that should not be affected by save */ unsigned int nr_copy_pages __nosavedata = 0; @@ -169,7 +169,7 @@ static int is_resume_device(const struct struct inode *inode = file->f_dentry->d_inode; return S_ISBLK(inode->i_mode) && - resume_device == MKDEV(imajor(inode), iminor(inode)); + swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); } static int swsusp_swap_check(void) /* This is called before saving image */ @@ -940,7 +940,7 @@ int swsusp_resume(void) /* * Returns true if given address/order collides with any orig_address */ -static int __init does_collide_order(unsigned long addr, int order) +static int does_collide_order(unsigned long addr, int order) { int i; @@ -974,7 +974,7 @@ static inline void eat_page(void *page) *eaten_memory = c; } -static unsigned long __init get_usable_page(unsigned gfp_mask) +static unsigned long get_usable_page(unsigned gfp_mask) { unsigned long m; @@ -988,7 +988,7 @@ static unsigned long __init get_usable_p return m; } -static void __init free_eaten_memory(void) +static void free_eaten_memory(void) { unsigned long m; void **c; @@ -1011,7 +1011,7 @@ static void __init free_eaten_memory(voi * pages later */ -static int __init check_pagedir(struct pbe *pblist) +static int check_pagedir(struct pbe *pblist) { struct pbe *p; @@ -1035,7 +1035,7 @@ static int __init check_pagedir(struct p * restore from the loaded pages later. We relocate them here. */ -static struct pbe * __init swsusp_pagedir_relocate(struct pbe *pblist) +static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist) { struct zone *zone; unsigned long zone_pfn; @@ -1184,7 +1184,7 @@ static int bio_write_page(pgoff_t page_o * I really don't think that it's foolproof but more than nothing.. */ -static const char * __init sanity_check(void) +static const char * sanity_check(void) { dump_info(); if(swsusp_info.version_code != LINUX_VERSION_CODE) @@ -1205,7 +1205,7 @@ static const char * __init sanity_check( } -static int __init check_header(void) +static int check_header(void) { const char * reason = NULL; int error; @@ -1223,7 +1223,7 @@ static int __init check_header(void) return error; } -static int __init check_sig(void) +static int check_sig(void) { int error; @@ -1253,7 +1253,7 @@ static int __init check_sig(void) * already did that. */ -static int __init data_read(struct pbe *pblist) +static int data_read(struct pbe *pblist) { struct pbe * p; int error = 0; @@ -1281,13 +1281,13 @@ static int __init data_read(struct pbe * return error; } -extern dev_t __init name_to_dev_t(const char *line); +extern dev_t name_to_dev_t(const char *line); /** * read_pagedir - Read page backup list pages from swap */ -static int __init read_pagedir(struct pbe *pblist) +static int read_pagedir(struct pbe *pblist) { struct pbe *pbpage, *p; unsigned i = 0; @@ -1321,10 +1321,9 @@ static int __init read_pagedir(struct pb } -static int __init read_suspend_image(void) +static int check_suspend_image(void) { int error = 0; - struct pbe *p; if ((error = check_sig())) return error; @@ -1332,6 +1331,14 @@ static int __init read_suspend_image(voi if ((error = check_header())) return error; + return 0; +} + +static int read_suspend_image(void) +{ + int error = 0; + struct pbe *p; + if (!(p = alloc_pagedir(nr_copy_pages))) return -ENOMEM; @@ -1362,30 +1369,72 @@ static int __init read_suspend_image(voi } /** - * swsusp_read - Read saved image from swap. + * swsusp_check - Check for saved image in swap */ -int __init swsusp_read(void) +int swsusp_check(void) { int error; - if (!strlen(resume_file)) - return -ENOENT; - - resume_device = name_to_dev_t(resume_file); - pr_debug("swsusp: Resume From Partition: %s\n", resume_file); + if (!swsusp_resume_device) { + if (!strlen(resume_file)) + return -ENOENT; + swsusp_resume_device = name_to_dev_t(resume_file); + pr_debug("swsusp: Resume From Partition %s\n", resume_file); + } else { + pr_debug("swsusp: Resume From Partition %d:%d\n", + MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device)); + } - resume_bdev = open_by_devnum(resume_device, FMODE_READ); + resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); if (!IS_ERR(resume_bdev)) { set_blocksize(resume_bdev, PAGE_SIZE); - error = read_suspend_image(); - blkdev_put(resume_bdev); + error = check_suspend_image(); + if (error) + blkdev_put(resume_bdev); } else error = PTR_ERR(resume_bdev); if (!error) - pr_debug("Reading resume file was successful\n"); + pr_debug("swsusp: resume file found\n"); + else + pr_debug("swsusp: Error %d check for resume file\n", error); + return error; +} + +/** + * swsusp_read - Read saved image from swap. + */ + +int swsusp_read(void) +{ + int error; + + if (IS_ERR(resume_bdev)) { + pr_debug("swsusp: block device not initialised\n"); + return PTR_ERR(resume_bdev); + } + + error = read_suspend_image(); + blkdev_put(resume_bdev); + + if (!error) + pr_debug("swsusp: Reading resume file was successful\n"); else pr_debug("swsusp: Error %d resuming\n", error); return error; } + +/** + * swsusp_close - close swap device. + */ + +void swsusp_close(void) +{ + if (IS_ERR(resume_bdev)) { + pr_debug("swsusp: block device not initialised\n"); + return; + } + + blkdev_put(resume_bdev); +} _