blob: e557b05c050b2abe2b312c27604d6141134c1545 [file] [log] [blame]
/*
* Handle resume from suspend-to-disk
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <sys/stat.h>
#include <sys/sysmacros.h>
#include "kinit.h"
#include "do_mounts.h"
#include "resume.h"
#ifndef CONFIG_PM_STD_PARTITION
# define CONFIG_PM_STD_PARTITION ""
#endif
int do_resume(int argc, char *argv[])
{
const char *resume_file = CONFIG_PM_STD_PARTITION;
const char *resume_arg;
unsigned long long resume_offset;
resume_arg = get_arg(argc, argv, "resume=");
resume_file = resume_arg ? resume_arg : resume_file;
/* No resume device specified */
if (!resume_file[0])
return 0;
resume_arg = get_arg(argc, argv, "resume_offset=");
resume_offset = resume_arg ? strtoull(resume_arg, NULL, 0) : 0ULL;
/* Fix: we either should consider reverting the device back to
ordinary swap, or (better) put that code into swapon */
/* Noresume requested */
if (get_flag(argc, argv, "noresume"))
return 0;
return resume(resume_file, resume_offset);
}
int resume(const char *resume_file, unsigned long long resume_offset)
{
dev_t resume_device;
int powerfd = -1;
char device_string[64];
int len;
resume_device = name_to_dev_t(resume_file);
if (major(resume_device) == 0) {
fprintf(stderr, "Invalid resume device: %s\n", resume_file);
goto failure;
}
if ((powerfd = open("/sys/power/resume", O_WRONLY)) < 0)
goto fail_r;
len = snprintf(device_string, sizeof device_string,
"%u:%u:%llu",
major(resume_device), minor(resume_device),
resume_offset);
/* This should never happen */
if (len >= sizeof device_string)
goto fail_r;
dprintf("kinit: trying to resume from %s\n", resume_file);
if (write(powerfd, device_string, len) != len)
goto fail_r;
/* Okay, what are we still doing alive... */
failure:
if (powerfd >= 0)
close(powerfd);
dprintf("kinit: No resume image, doing normal boot...\n");
return -1;
fail_r:
fprintf(stderr, "Cannot write /sys/power/resume "
"(no software suspend kernel support?)\n");
goto failure;
}