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(path: "/sys/class/leds/hp::hddprotect/brightness" , i: on); |
78 | } |
79 | |
80 | static void protect(int seconds) |
81 | { |
82 | const char *str = (seconds == 0) ? "Unparked" : "Parked" ; |
83 | |
84 | write_int(path: unload_heads_path, i: 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(seconds: 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(seconds: 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 | |