1 /* Disk protection for HP machines.
2 *
3 * Copyright 2008 Eric Piel
4 * Copyright 2009 Pavel Machek <pavel@ucw.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
set_unload_heads_path(char * device)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 }
valid_disk(void)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
write_int(char * path,int i)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
set_led(int on)64 void set_led(int on)
65 {
66 write_int("/sys/class/leds/hp::hddprotect/brightness", on);
67 }
68
protect(int seconds)69 void protect(int seconds)
70 {
71 write_int(unload_heads_path, seconds*1000);
72 }
73
on_ac(void)74 int on_ac(void)
75 {
76 // /sys/class/power_supply/AC0/online
77 }
78
lid_open(void)79 int lid_open(void)
80 {
81 // /proc/acpi/button/lid/LID/state
82 }
83
ignore_me(void)84 void ignore_me(void)
85 {
86 protect(0);
87 set_led(0);
88 }
89
main(int argc,char ** argv)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 }
147