1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 #include <door.h>
28 #include <locale.h>
29 #include <meta.h>
30 #include <strings.h>
31 #include <syslog.h>
32
33 static pid_t enter_daemon_lock(void);
34 static void exit_daemon_lock(void);
35 #define DAEMON_LOCK_FILE "/var/run/.mddoors.lock"
36
37 static int hold_daemon_lock;
38 static const char *daemon_lock_file = DAEMON_LOCK_FILE;
39 static int daemon_lock_fd;
40
41 void
daemon_cleanup()42 daemon_cleanup()
43 {
44 if (hold_daemon_lock) {
45 meta_mirror_resync_block_all();
46 exit_daemon_lock();
47 }
48 }
49
50 /*
51 * Use an advisory lock to ensure that only one daemon process is
52 * active at any point in time.
53 */
54 static pid_t
enter_daemon_lock(void)55 enter_daemon_lock(void)
56 {
57 struct flock lock;
58
59 daemon_lock_fd = open(daemon_lock_file, O_CREAT|O_RDWR, 0644);
60
61 if (daemon_lock_fd < 0) {
62 exit(-1);
63 }
64
65 lock.l_type = F_WRLCK;
66 lock.l_whence = SEEK_SET;
67 lock.l_start = 0;
68 lock.l_len = 0;
69
70 if (fcntl(daemon_lock_fd, F_SETLK, &lock) == -1) {
71
72 if (errno == EAGAIN || errno == EDEADLK) {
73
74 if (fcntl(daemon_lock_fd, F_GETLK, &lock) == -1) {
75 exit(1);
76 }
77 return (lock.l_pid);
78 }
79 }
80 hold_daemon_lock = 1;
81 return (getpid());
82 }
83
84
85 /*
86 * Drop the advisory daemon lock, close lock file
87 */
88 static void
exit_daemon_lock(void)89 exit_daemon_lock(void)
90 {
91 struct flock lock;
92
93 lock.l_type = F_UNLCK;
94 lock.l_whence = SEEK_SET;
95 lock.l_start = 0;
96 lock.l_len = 0;
97
98 if (fcntl(daemon_lock_fd, F_SETLK, &lock) == -1) {
99 syslog(LOG_DAEMON | LOG_DEBUG, gettext("unlock(%s) - %s"),
100 daemon_lock_file, strerror(errno));
101 return;
102 }
103
104 if (close(daemon_lock_fd) == -1) {
105 syslog(LOG_DAEMON | LOG_DEBUG,
106 gettext("close(%s) failed - %s\n"),
107 daemon_lock_file, strerror(errno));
108 return;
109 }
110 (void) unlink(daemon_lock_file);
111 }
112
113 /*
114 * Purpose of this routine is to accept a message from the local kernel and
115 * send this message using rpc to the master node.
116 * when an ok comes from the master we call door_return()
117 */
118
119 /* ARGSUSED */
120 static void
door2rpc(void * cookie,char * argp,size_t arg_size,door_desc_t * dp,uint_t n_desc)121 door2rpc(void *cookie, /* required by the doors infrastructure */
122 char *argp,
123 size_t arg_size, /* required by the doors infrastructure */
124 door_desc_t *dp, /* required by the doors infrastructure */
125 uint_t n_desc) /* required by the doors infrastructure */
126 {
127 int err;
128 int size;
129 md_error_t ep = mdnullerror;
130 md_mn_result_t *result = NULL;
131 md_mn_kresult_t kresult;
132
133 md_mn_kmsg_t *kmsg = (md_mn_kmsg_t *)(void *)argp;
134 err = mdmn_send_message(kmsg->kmsg_setno, kmsg->kmsg_type,
135 kmsg->kmsg_flags, kmsg->kmsg_recipient, (char *)&(kmsg->kmsg_data),
136 kmsg->kmsg_size, &result, &ep);
137
138 if (result == NULL) {
139 kresult.kmmr_comm_state = MDMNE_RPC_FAIL;
140 } else {
141 kresult.kmmr_comm_state = result->mmr_comm_state;
142 if (err == 0) {
143 kresult.kmmr_msgtype = result->mmr_msgtype;
144 kresult.kmmr_flags = result->mmr_flags;
145 kresult.kmmr_exitval = result->mmr_exitval;
146 kresult.kmmr_failing_node = result->mmr_failing_node;
147 size = result->mmr_out_size;
148 if (size > 0) {
149 /* This is the max data we can transfer, here */
150 if (size > MDMN_MAX_KRES_DATA) {
151 size = MDMN_MAX_KRES_DATA;
152 }
153 bcopy(result->mmr_out, &(kresult.kmmr_res_data),
154 size);
155 kresult.kmmr_res_size = size;
156 } else {
157 kresult.kmmr_res_size = 0;
158 }
159 }
160 free_result(result);
161 }
162
163 (void) door_return((char *)&kresult, sizeof (md_mn_kresult_t), NULL, 0);
164 }
165
166
167 /* ARGSUSED */
168 int
main(void)169 main(void)
170 {
171
172 int i;
173 int mdmn_door_handle;
174 pid_t pid;
175 int size;
176 md_error_t ep = mdnullerror;
177 struct rlimit rl;
178
179 /*
180 * Get the locale set up before calling any other routines
181 * with messages to ouput. Just in case we're not in a build
182 * environment, make sure that TEXT_DOMAIN gets set to
183 * something.
184 */
185 #if !defined(TEXT_DOMAIN)
186 #define TEXT_DOMAIN "SYS_TEST"
187 #endif
188 (void) setlocale(LC_ALL, "");
189 (void) textdomain(TEXT_DOMAIN);
190
191 openlog("mddoors", LOG_PID, LOG_DAEMON);
192
193 /* here beginneth the daemonizing code */
194 pid = fork();
195 if (pid < 0) {
196 syslog(LOG_DAEMON | LOG_ERR, gettext("Cannot fork"));
197 exit(1);
198 }
199
200 if (pid) {
201 exit(0);
202 }
203
204 /*
205 * Only one daemon can run at a time.
206 * If another instance is already running, this is not an error.
207 */
208 if ((pid = enter_daemon_lock()) != getpid()) {
209 exit(0);
210 }
211
212 rl.rlim_max = 0;
213 (void) getrlimit(RLIMIT_NOFILE, &rl);
214 if ((size = rl.rlim_max) == 0) {
215 syslog(LOG_DAEMON | LOG_ERR, gettext("Cannot getrlimit"));
216 exit(1);
217 }
218
219 for (i = 0; i < size; i++) {
220 if (i == daemon_lock_fd)
221 continue;
222 (void) close(i);
223 }
224
225
226 i = open("/dev/null", 2);
227 (void) dup2(i, 1);
228 (void) dup2(i, 2);
229 (void) setsid();
230
231 /* here endeth the daemonizing code */
232
233 /* Block out the usual signals so we don't get killed unintentionally */
234 (void) signal(SIGHUP, SIG_IGN);
235 (void) signal(SIGINT, SIG_IGN);
236 (void) signal(SIGQUIT, SIG_IGN);
237 (void) signal(SIGTERM, SIG_IGN);
238
239 (void) atexit(daemon_cleanup);
240
241 /* Resume any previously blocked resync */
242 meta_mirror_resync_unblock_all();
243
244 /*
245 * At this point we are single threaded.
246 * We give mdmn_send_message() a chance to initialize safely.
247 */
248 (void) mdmn_send_message(0, 0, 0, 0, 0, 0, 0, 0);
249
250 /* setup the door handle */
251 mdmn_door_handle = door_create(door2rpc, NULL,
252 DOOR_REFUSE_DESC | DOOR_NO_CANCEL);
253 if (mdmn_door_handle == -1) {
254 perror(gettext("door_create failed"));
255 syslog(LOG_DAEMON | LOG_ERR, gettext("door_create failed"));
256 exit(1);
257 }
258
259 if (metaioctl(MD_MN_SET_DOORH, &mdmn_door_handle, &ep,
260 "mddoors") != 0) {
261 syslog(LOG_DAEMON | LOG_DEBUG, gettext(
262 "Couldn't set door handle"));
263 exit(1);
264 }
265
266 (void) pause();
267 syslog(LOG_DAEMON | LOG_ERR, gettext(
268 "Unexpected exit from pause()"));
269 return (1);
270 }
271