1 /* Disk protection for HP/DELL machines.
2 *
3 * Copyright 2008 Eric Piel
4 * Copyright 2009 Pavel Machek <pavel@ucw.cz>
5 * Copyright 2012 Sonal Santan
6 * Copyright 2014 Pali Rohár <pali.rohar@gmail.com>
7 *
8 * GPLv2.
9 */
10
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <unistd.h>
14 #include <fcntl.h>
15 #include <sys/stat.h>
16 #include <sys/types.h>
17 #include <string.h>
18 #include <stdint.h>
19 #include <errno.h>
20 #include <signal.h>
21 #include <sys/mman.h>
22 #include <sched.h>
23 #include <syslog.h>
24
25 static int noled;
26 static char unload_heads_path[64];
27 static char device_path[32];
28 static const char app_name[] = "FREE FALL";
29
set_unload_heads_path(char * device)30 static int set_unload_heads_path(char *device)
31 {
32 if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0)
33 return -EINVAL;
34 strncpy(device_path, device, sizeof(device_path) - 1);
35
36 snprintf(unload_heads_path, sizeof(unload_heads_path) - 1,
37 "/sys/block/%s/device/unload_heads", device+5);
38 return 0;
39 }
40
valid_disk(void)41 static int valid_disk(void)
42 {
43 int fd = open(unload_heads_path, O_RDONLY);
44
45 if (fd < 0) {
46 perror(unload_heads_path);
47 return 0;
48 }
49
50 close(fd);
51 return 1;
52 }
53
write_int(char * path,int i)54 static void write_int(char *path, int i)
55 {
56 char buf[1024];
57 int fd = open(path, O_RDWR);
58
59 if (fd < 0) {
60 perror("open");
61 exit(1);
62 }
63
64 sprintf(buf, "%d", i);
65
66 if (write(fd, buf, strlen(buf)) != strlen(buf)) {
67 perror("write");
68 exit(1);
69 }
70
71 close(fd);
72 }
73
set_led(int on)74 static void set_led(int on)
75 {
76 if (noled)
77 return;
78 write_int("/sys/class/leds/hp::hddprotect/brightness", on);
79 }
80
protect(int seconds)81 static void protect(int seconds)
82 {
83 const char *str = (seconds == 0) ? "Unparked" : "Parked";
84
85 write_int(unload_heads_path, seconds*1000);
86 syslog(LOG_INFO, "%s %s disk head\n", str, device_path);
87 }
88
on_ac(void)89 static int on_ac(void)
90 {
91 /* /sys/class/power_supply/AC0/online */
92 return 1;
93 }
94
lid_open(void)95 static int lid_open(void)
96 {
97 /* /proc/acpi/button/lid/LID/state */
98 return 1;
99 }
100
ignore_me(int signum)101 static void ignore_me(int signum)
102 {
103 protect(0);
104 set_led(0);
105 }
106
main(int argc,char ** argv)107 int main(int argc, char **argv)
108 {
109 int fd, ret;
110 struct stat st;
111 struct sched_param param;
112
113 if (argc == 1)
114 ret = set_unload_heads_path("/dev/sda");
115 else if (argc == 2)
116 ret = set_unload_heads_path(argv[1]);
117 else
118 ret = -EINVAL;
119
120 if (ret || !valid_disk()) {
121 fprintf(stderr, "usage: %s <device> (default: /dev/sda)\n",
122 argv[0]);
123 exit(1);
124 }
125
126 fd = open("/dev/freefall", O_RDONLY);
127 if (fd < 0) {
128 perror("/dev/freefall");
129 return EXIT_FAILURE;
130 }
131
132 if (stat("/sys/class/leds/hp::hddprotect/brightness", &st))
133 noled = 1;
134
135 if (daemon(0, 0) != 0) {
136 perror("daemon");
137 return EXIT_FAILURE;
138 }
139
140 openlog(app_name, LOG_CONS | LOG_PID | LOG_NDELAY, LOG_LOCAL1);
141
142 param.sched_priority = sched_get_priority_max(SCHED_FIFO);
143 sched_setscheduler(0, SCHED_FIFO, ¶m);
144 mlockall(MCL_CURRENT|MCL_FUTURE);
145
146 signal(SIGALRM, ignore_me);
147
148 for (;;) {
149 unsigned char count;
150
151 ret = read(fd, &count, sizeof(count));
152 alarm(0);
153 if ((ret == -1) && (errno == EINTR)) {
154 /* Alarm expired, time to unpark the heads */
155 continue;
156 }
157
158 if (ret != sizeof(count)) {
159 perror("read");
160 break;
161 }
162
163 protect(21);
164 set_led(1);
165 if (1 || on_ac() || lid_open())
166 alarm(2);
167 else
168 alarm(20);
169 }
170
171 closelog();
172 close(fd);
173 return EXIT_SUCCESS;
174 }
175