| 1 | /* Disk protection for HP machines. |
| 2 | * |
| 3 | * Copyright 2008 Eric Piel |
| 4 | * Copyright 2009 Pavel Machek <pavel@suse.cz> |
| 5 | * |
| 6 | * GPLv2. |
| 7 | */ |
| 8 | |
| 9 | #include <stdio.h> |
| 10 | #include <stdlib.h> |
| 11 | #include <unistd.h> |
| 12 | #include <fcntl.h> |
| 13 | #include <sys/stat.h> |
| 14 | #include <sys/types.h> |
| 15 | #include <string.h> |
| 16 | #include <stdint.h> |
| 17 | #include <errno.h> |
| 18 | #include <signal.h> |
| 19 | #include <sys/mman.h> |
| 20 | #include <sched.h> |
| 21 | |
| 22 | char unload_heads_path[64]; |
| 23 | |
| 24 | int set_unload_heads_path(char *device) |
| 25 | { |
| 26 | char devname[64]; |
| 27 | |
| 28 | if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0) |
| 29 | return -EINVAL; |
| 30 | strncpy(devname, device + 5, sizeof(devname)); |
| 31 | |
| 32 | snprintf(unload_heads_path, sizeof(unload_heads_path), |
| 33 | "/sys/block/%s/device/unload_heads", devname); |
| 34 | return 0; |
| 35 | } |
| 36 | int valid_disk(void) |
| 37 | { |
| 38 | int fd = open(unload_heads_path, O_RDONLY); |
| 39 | if (fd < 0) { |
| 40 | perror(unload_heads_path); |
| 41 | return 0; |
| 42 | } |
| 43 | |
| 44 | close(fd); |
| 45 | return 1; |
| 46 | } |
| 47 | |
| 48 | void write_int(char *path, int i) |
| 49 | { |
| 50 | char buf[1024]; |
| 51 | int fd = open(path, O_RDWR); |
| 52 | if (fd < 0) { |
| 53 | perror("open"); |
| 54 | exit(1); |
| 55 | } |
| 56 | sprintf(buf, "%d", i); |
| 57 | if (write(fd, buf, strlen(buf)) != strlen(buf)) { |
| 58 | perror("write"); |
| 59 | exit(1); |
| 60 | } |
| 61 | close(fd); |
| 62 | } |
| 63 | |
| 64 | void set_led(int on) |
| 65 | { |
| 66 | write_int("/sys/class/leds/hp::hddprotect/brightness", on); |
| 67 | } |
| 68 | |
| 69 | void protect(int seconds) |
| 70 | { |
| 71 | write_int(unload_heads_path, seconds*1000); |
| 72 | } |
| 73 | |
| 74 | int on_ac(void) |
| 75 | { |
| 76 | // /sys/class/power_supply/AC0/online |
| 77 | } |
| 78 | |
| 79 | int lid_open(void) |
| 80 | { |
| 81 | // /proc/acpi/button/lid/LID/state |
| 82 | } |
| 83 | |
| 84 | void ignore_me(void) |
| 85 | { |
| 86 | protect(0); |
| 87 | set_led(0); |
| 88 | } |
| 89 | |
| 90 | int main(int argc, char **argv) |
| 91 | { |
| 92 | int fd, ret; |
| 93 | struct sched_param param; |
| 94 | |
| 95 | if (argc == 1) |
| 96 | ret = set_unload_heads_path("/dev/sda"); |
| 97 | else if (argc == 2) |
| 98 | ret = set_unload_heads_path(argv[1]); |
| 99 | else |
| 100 | ret = -EINVAL; |
| 101 | |
| 102 | if (ret || !valid_disk()) { |
| 103 | fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n", |
| 104 | argv[0]); |
| 105 | exit(1); |
| 106 | } |
| 107 | |
| 108 | fd = open("/dev/freefall", O_RDONLY); |
| 109 | if (fd < 0) { |
| 110 | perror("/dev/freefall"); |
| 111 | return EXIT_FAILURE; |
| 112 | } |
| 113 | |
| 114 | daemon(0, 0); |
| 115 | param.sched_priority = sched_get_priority_max(SCHED_FIFO); |
| 116 | sched_setscheduler(0, SCHED_FIFO, ¶m); |
| 117 | mlockall(MCL_CURRENT|MCL_FUTURE); |
| 118 | |
| 119 | signal(SIGALRM, ignore_me); |
| 120 | |
| 121 | for (;;) { |
| 122 | unsigned char count; |
| 123 | |
| 124 | ret = read(fd, &count, sizeof(count)); |
| 125 | alarm(0); |
| 126 | if ((ret == -1) && (errno == EINTR)) { |
| 127 | /* Alarm expired, time to unpark the heads */ |
| 128 | continue; |
| 129 | } |
| 130 | |
| 131 | if (ret != sizeof(count)) { |
| 132 | perror("read"); |
| 133 | break; |
| 134 | } |
| 135 | |
| 136 | protect(21); |
| 137 | set_led(1); |
| 138 | if (1 || on_ac() || lid_open()) |
| 139 | alarm(2); |
| 140 | else |
| 141 | alarm(20); |
| 142 | } |
| 143 | |
| 144 | close(fd); |
| 145 | return EXIT_SUCCESS; |
| 146 | } |