1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Disk protection for HP/DELL machines. 3 * 4 * Copyright 2008 Eric Piel 5 * Copyright 2009 Pavel Machek <pavel@ucw.cz> 6 * Copyright 2012 Sonal Santan 7 * 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 24 static int noled; 25 static char unload_heads_path[64]; 26 static char device_path[32]; 27 static const char app_name[] = "FREE FALL"; 28 29 static 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 40 static 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 53 static 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 73 static void set_led(int on) 74 { 75 if (noled) 76 return; 77 write_int("/sys/class/leds/hp::hddprotect/brightness", on); 78 } 79 80 static 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 88 static int on_ac(void) 89 { 90 /* /sys/class/power_supply/AC0/online */ 91 return 1; 92 } 93 94 static int lid_open(void) 95 { 96 /* /proc/acpi/button/lid/LID/state */ 97 return 1; 98 } 99 100 static void ignore_me(int signum) 101 { 102 protect(0); 103 set_led(0); 104 } 105 106 int 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 else 117 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 else 167 alarm(20); 168 } 169 170 closelog(); 171 close(fd); 172 return EXIT_SUCCESS; 173 } 174