1 /* $NetBSD: cleansrv.c,v 1.4 2013/06/06 00:53:35 dholland Exp $ */
2
3 /*-
4 * Copyright (c) 2005 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Konrad E. Schroder <perseant@hhhh.org>.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #ifdef USE_CLIENT_SERVER
33
34 #include <errno.h>
35 #include <fcntl.h>
36 #include <stdio.h>
37 #include <sys/syslog.h>
38 #include <sys/param.h>
39 #include <sys/mount.h>
40 #include <sys/socket.h>
41 #include <sys/un.h>
42 #include <ufs/lfs/ulfs_inode.h>
43 #include <ufs/lfs/lfs.h>
44
45 #include "bufcache.h"
46 #include "vnode.h"
47 #include "lfs.h"
48 #include "fdfs.h"
49 #include "cleaner.h"
50
51 #define LFS_CLEANERD_SOCKDIR "/tmp/.lfs_cleanerd"
52 #define LFS_CLEANERD_SOCKFILE LFS_CLEANERD_SOCKDIR "/socket"
53
54 int control_socket = -1;
55 extern int nfss;
56 extern struct clfs **fsp;
57
58 struct lfs_cleanerd_cmd {
59 int cmd;
60 int len;
61 char data[PATH_MAX];
62 };
63
64 void
check_control_socket(void)65 check_control_socket(void)
66 {
67 int c, r;
68 struct lfs_cleanerd_cmd cmd;
69 struct clfs **nfsp;
70
71 if (control_socket < 0)
72 return;
73
74 while(1) {
75 ioctl(control_socket, FIONREAD, &c);
76 if (c <= 0)
77 return;
78 read(control_socket, (char *)&cmd, sizeof(cmd));
79
80 switch(cmd.cmd) {
81 case 'C': /* Add filesystem for cleaning */
82 ++nfss;
83 nfsp = (struct clfs **)realloc(fsp,
84 nfss * sizeof(*fsp));
85 if (nfsp == NULL) {
86 --nfss;
87 break;
88 }
89 fsp = nfsp;
90
91 fsp[nfss - 1] = (struct clfs *)malloc(sizeof(**fsp));
92 if (fsp[nfss - 1] == NULL) {
93 syslog(LOG_ERR, "%s: couldn't alloc memory: %m"
94 cmd.data);
95 --nfsp;
96 break;
97 }
98
99 if ((r = init_fs(fsp[nfss - 1], cmd.data)) < 0) {
100 syslog(LOG_ERR, "%s: couldn't init: "
101 "error code %d", cmd.data, r);
102 handle_error(fsp, nfss - 1);
103 }
104 break;
105 default:
106 syslog(LOG_NOTICE, "unknown message type %d", cmd.cmd);
107 break;
108 }
109 }
110 }
111
112 static int
send_fss_to_master(int argc,char ** argv)113 send_fss_to_master(int argc, char **argv)
114 {
115 struct sockaddr_un sun;
116 struct lfs_cleanerd_cmd cmd;
117 int i, r, s;
118
119 strcpy(sun.sun_path, LFS_CLEANERD_SOCKFILE);
120 sun.sun_family = AF_LOCAL;
121 sun.sun_len = sizeof(sa_family_t) + 1 + strlen(sun.sun_path);
122
123 s = socket(PF_LOCAL, SOCK_DGRAM, 0);
124 if (s < 0) {
125 syslog(LOG_DEBUG, "open failed: %m");
126 return -1;
127 }
128
129 cmd.cmd = 'C';
130 for (i = 0; i < argc; i++) {
131 strncpy(cmd.data, argv[i], PATH_MAX);
132 cmd.len = 2 * sizeof(int) + strlen(cmd.data) + 1;
133 r = sendto(s, &cmd, sizeof(cmd), 0, (struct sockaddr *)&sun,
134 sizeof(sun));
135 if (r < 0) {
136 syslog(LOG_DEBUG, "sendto failed: %m");
137 return -1;
138 }
139 }
140 return 0;
141 }
142
143 static void
sig_donothing(int sig)144 sig_donothing(int sig)
145 {
146 /* Do nothing */
147 dlog("caught sigio");
148 }
149
150 static void
cleanup_socket(void)151 cleanup_socket(void)
152 {
153 if (control_socket >= 0) {
154 close(control_socket);
155 unlink(LFS_CLEANERD_SOCKFILE);
156 rmdir(LFS_CLEANERD_SOCKDIR);
157 }
158 }
159
160 void
try_to_become_master(int argc,char ** argv)161 try_to_become_master(int argc, char **argv)
162 {
163 struct sockaddr_un sun;
164 int fd;
165 int pid;
166 int flags;
167 char scratch[80];
168
169 if (mkdir(LFS_CLEANERD_SOCKDIR, 0700) < 0) {
170 if (errno != EEXIST)
171 return;
172 pid = 0;
173 fd = open("/var/run/lfs_cleanerd.pid", O_RDONLY);
174 if (fd >= 0) {
175 read(fd, scratch, 80);
176 scratch[79] = '\0';
177 pid = atoi(scratch);
178 if (kill(pid, 0) == 0) {
179 send_fss_to_master(argc, argv);
180 exit(0);
181 }
182 close(fd);
183 }
184
185 /*
186 * Master is no longer present even though directory
187 * exists. Remove the socket and proceed. There is
188 * a race condition here which could result in more than
189 * one master daemon. That would not be a catastrophe.
190 */
191 if (unlink(LFS_CLEANERD_SOCKFILE) != 0)
192 return;
193 }
194
195 /*
196 * Create the socket and bind it in the namespace
197 */
198 control_socket = socket(PF_LOCAL, SOCK_DGRAM, 0);
199 strcpy(sun.sun_path, LFS_CLEANERD_SOCKFILE);
200 sun.sun_family = AF_LOCAL;
201 sun.sun_len = sizeof(sa_family_t) + 1 + strlen(sun.sun_path);
202 bind(control_socket, (struct sockaddr *)&sun, sizeof(sun));
203
204 /* Clean up when we leave */
205 atexit(cleanup_socket);
206
207 /*
208 * Wake us when there is i/o on this socket. We don't need
209 * to actually do anything when we get the signal, but we
210 * have to install a signal handler so LFCNSEGWAIT will be
211 * interrupted when data comes in on the socket.
212 */
213 fcntl(control_socket, F_SETOWN, getpid());
214 flags = fcntl(control_socket, F_GETFL, NULL);
215 flags |= O_ASYNC;
216 fcntl(control_socket, F_SETFL, flags);
217 signal(SIGIO, sig_donothing);
218
219 /* And finally record our pid */
220 pidfile("lfs_cleanerd");
221 }
222 #endif /* USE_CLIENT_SERVER */
223