| /* |
| * resume.c |
| * |
| * Handle resume from suspend-to-disk |
| */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <limits.h> |
| #include <sys/stat.h> |
| #include <sys/sysmacros.h> |
| #include <linux/config.h> /* For CONFIG_PM_STD_PARTITION */ |
| |
| #include "kinit.h" |
| #include "do_mounts.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; |
| dev_t resume_device; |
| int powerfd = -1; |
| char device_string[64]; |
| int len; |
| |
| resume_arg = get_arg(argc, argv, "resume="); |
| resume_file = resume_arg ? resume_arg : resume_file; |
| if (!resume_file[0]) |
| return 0; /* No resume device specified */ |
| |
| /* Fix: we either should consider reverting the device back to |
| ordinary swap, or (better) put that code into swapon */ |
| if (get_flag(argc, argv, "noresume")) |
| return 0; /* Noresume requested */ |
| |
| 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", |
| major(resume_device), minor(resume_device)); |
| |
| if (len >= sizeof device_string) |
| goto fail_r; /* This should never happen */ |
| |
| DEBUG(("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); |
| fprintf(stderr, "Resume failed, doing normal boot...\n"); |
| return -1; |
| |
| fail_r: |
| fprintf(stderr, |
| "Resume failed: cannot write /sys/power/resume (no kernel support?)\n"); |
| goto failure; |
| } |