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1// SPDX-License-Identifier: GPL-2.0-only2/* Disk protection for HP/DELL machines.3 *4 * Copyright 2008 Eric Piel5 * Copyright 2009 Pavel Machek <pavel@ucw.cz>6 * Copyright 2012 Sonal Santan7 * Copyright 2014 Pali Rohár <pali@kernel.org>8 */9 10#include <stdio.h>11#include <stdlib.h>12#include <unistd.h>13#include <fcntl.h>14#include <sys/stat.h>15#include <sys/types.h>16#include <string.h>17#include <stdint.h>18#include <errno.h>19#include <signal.h>20#include <sys/mman.h>21#include <sched.h>22#include <syslog.h>23 24static int noled;25static char unload_heads_path[64];26static char device_path[32];27static const char app_name[] = "FREE FALL";28 29static int set_unload_heads_path(char *device)30{31 if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0)32 return -EINVAL;33 strncpy(device_path, device, sizeof(device_path) - 1);34 35 snprintf(unload_heads_path, sizeof(unload_heads_path) - 1,36 "/sys/block/%s/device/unload_heads", device+5);37 return 0;38}39 40static int valid_disk(void)41{42 int fd = open(unload_heads_path, O_RDONLY);43 44 if (fd < 0) {45 perror(unload_heads_path);46 return 0;47 }48 49 close(fd);50 return 1;51}52 53static void write_int(char *path, int i)54{55 char buf[1024];56 int fd = open(path, O_RDWR);57 58 if (fd < 0) {59 perror("open");60 exit(1);61 }62 63 sprintf(buf, "%d", i);64 65 if (write(fd, buf, strlen(buf)) != strlen(buf)) {66 perror("write");67 exit(1);68 }69 70 close(fd);71}72 73static void set_led(int on)74{75 if (noled)76 return;77 write_int("/sys/class/leds/hp::hddprotect/brightness", on);78}79 80static void protect(int seconds)81{82 const char *str = (seconds == 0) ? "Unparked" : "Parked";83 84 write_int(unload_heads_path, seconds*1000);85 syslog(LOG_INFO, "%s %s disk head\n", str, device_path);86}87 88static int on_ac(void)89{90 /* /sys/class/power_supply/AC0/online */91 return 1;92}93 94static int lid_open(void)95{96 /* /proc/acpi/button/lid/LID/state */97 return 1;98}99 100static void ignore_me(int signum)101{102 protect(0);103 set_led(0);104}105 106int main(int argc, char **argv)107{108 int fd, ret;109 struct stat st;110 struct sched_param param;111 112 if (argc == 1)113 ret = set_unload_heads_path("/dev/sda");114 else if (argc == 2)115 ret = set_unload_heads_path(argv[1]);116 else117 ret = -EINVAL;118 119 if (ret || !valid_disk()) {120 fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n",121 argv[0]);122 exit(1);123 }124 125 fd = open("/dev/freefall", O_RDONLY);126 if (fd < 0) {127 perror("/dev/freefall");128 return EXIT_FAILURE;129 }130 131 if (stat("/sys/class/leds/hp::hddprotect/brightness", &st))132 noled = 1;133 134 if (daemon(0, 0) != 0) {135 perror("daemon");136 return EXIT_FAILURE;137 }138 139 openlog(app_name, LOG_CONS | LOG_PID | LOG_NDELAY, LOG_LOCAL1);140 141 param.sched_priority = sched_get_priority_max(SCHED_FIFO);142 sched_setscheduler(0, SCHED_FIFO, ¶m);143 mlockall(MCL_CURRENT|MCL_FUTURE);144 145 signal(SIGALRM, ignore_me);146 147 for (;;) {148 unsigned char count;149 150 ret = read(fd, &count, sizeof(count));151 alarm(0);152 if ((ret == -1) && (errno == EINTR)) {153 /* Alarm expired, time to unpark the heads */154 continue;155 }156 157 if (ret != sizeof(count)) {158 perror("read");159 break;160 }161 162 protect(21);163 set_led(1);164 if (1 || on_ac() || lid_open())165 alarm(2);166 else167 alarm(20);168 }169 170 closelog();171 close(fd);172 return EXIT_SUCCESS;173}174