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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * -----------------------------------------------------------------
24 *
25 * umount.c
26 *
27 * CFS specific umount command.
28 */
29
30 #pragma ident "%Z%%M% %I% %E% SMI"
31
32 /*
33 * Copyright 2004 Sun Microsystems, Inc. All rights reserved.
34 * Use is subject to license terms.
35 */
36
37 #include <locale.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <stdarg.h>
42 #include <unistd.h>
43 #include <limits.h>
44 #include <errno.h>
45 #include <wait.h>
46 #include <ctype.h>
47 #include <fcntl.h>
48 #include <signal.h>
49 #include <sys/types.h>
50 #include <sys/param.h>
51 #include <sys/stat.h>
52 #include <sys/fcntl.h>
53 #include <sys/mount.h>
54 #include <sys/mntent.h>
55 #include <sys/mnttab.h>
56 #include <sys/fs/cachefs_fs.h>
57 #include <fslib.h>
58 #include <sys/utsname.h>
59 #include <rpc/rpc.h>
60 #include "../common/subr.h"
61 #include "../common/cachefsd.h"
62
63 /* forward references */
64 void pr_err(char *fmt, ...);
65 void usage(char *msgp);
66 int daemon_unmount(char *mntptp, int);
67
68 /*
69 *
70 * main
71 *
72 * Description:
73 * Main routine for the cfs umount program.
74 * Arguments:
75 * argc number of command line arguments
76 * argv list of command line arguments
77 * Returns:
78 * Returns 0 for success or 1 if an error occurs.
79 * Preconditions:
80 */
81
82 int
83 main(int argc, char **argv)
84 {
85 char *strp;
86 int xx;
87 int ret;
88 struct mnttab mget;
89 struct mnttab mref;
90 FILE *finp;
91 char mnt_front[PATH_MAX];
92 char mnt_back[PATH_MAX];
93 char *p, mnt_frontns[PATH_MAX];
94 pid_t pid;
95 int stat_loc;
96 char *cachedirp, *s;
97 int ufd, c;
98 int flag = 0;
99
100 (void) setlocale(LC_ALL, "");
101 #if !defined(TEXT_DOMAIN)
102 #define TEXT_DOMAIN "SYS_TEST"
103 #endif
104 (void) textdomain(TEXT_DOMAIN);
105
106 /*
107 * Set options
108 */
109 while ((c = getopt(argc, argv, "f")) != EOF) {
110 switch (c) {
111 case 'f':
112 flag |= MS_FORCE; /* forced unmount is desired */
113 break;
114 default:
115 usage("Incorrect number of arguments specified");
116 return (1);
117 }
118 }
119 if (flag & MS_FORCE)
120 strcpy(mnt_front, argv[2]);
121 else
122 strcpy(mnt_front, argv[1]);
123 mnt_back[0] = '\0';
124
125 if (strlen(argv[1]) >= (size_t)PATH_MAX) {
126 pr_err(gettext("name too long"));
127 return (1);
128 }
129
130 /*
131 * An unmount from autofs may have a
132 * space appended to the path.
133 * Trim it off before attempting to
134 * match the mountpoint in mnttab
135 */
136 strcpy(mnt_frontns, mnt_front);
137 p = &mnt_frontns[strlen(mnt_frontns) - 1];
138 if (*p == ' ')
139 *p = '\0';
140
141 /* get the mount point and the back file system mount point */
142 finp = fopen(MNTTAB, "r");
143 if (finp) {
144 mntnull(&mref);
145 mref.mnt_mountp = mnt_frontns;
146 mref.mnt_fstype = "cachefs";
147 ret = getmntany(finp, &mget, &mref);
148
149 cachedirp = (char *)malloc(strlen(mget.mnt_special) + 1);
150 strcpy(cachedirp, mget.mnt_special);
151 /*
152 * AutoClient mounts do not have .cfs_mnt_points string in
153 * them, so strstr would return NULL. So .cfs_unmnt file
154 * is not updated.
155 */
156 if ((s = strstr(cachedirp, ".cfs_mnt_points")) != NULL) {
157 time32_t btime;
158
159 xx = -1;
160 cachedirp[s-cachedirp] = '\0';
161 strcat(cachedirp, CACHEFS_UNMNT_FILE);
162 if ((ufd = open(cachedirp, O_WRONLY|O_CREAT|O_TRUNC,
163 0600)) > 0) {
164 if ((btime = get_boottime()) != -1)
165 xx = write(ufd, &btime, sizeof (time32_t));
166 close(ufd);
167 }
168 if (xx < 0)
169 pr_err(gettext(".cfs_unmnt error"));
170 }
171
172 if (ret != -1) {
173 if (mget.mnt_special)
174 strcpy(mnt_back, mget.mnt_special);
175 } else {
176 mref.mnt_special = mref.mnt_mountp;
177 mref.mnt_mountp = NULL;
178 rewind(finp);
179 ret = getmntany(finp, &mget, &mref);
180 if (ret != -1) {
181 strcpy(mnt_front, mget.mnt_mountp);
182 if (mget.mnt_special)
183 strcpy(mnt_back, mget.mnt_special);
184 } else {
185 pr_err(gettext("warning: %s not in mnttab"),
186 mref.mnt_special);
187 }
188 }
189 fclose(finp);
190 }
191
192 /* try to get the daemon to unmount this file system for us */
193 xx = daemon_unmount(mnt_front, flag);
194 if (xx == ENOTSUP)
195 return (1);
196 if (xx == EBUSY) {
197 pr_err(gettext("%s %s"), mnt_front, strerror(xx));
198 return (1);
199 }
200 if (xx == EIO) {
201 /* try to unmount the file system directly */
202 if (umount2(mnt_front, flag) == -1) {
203 pr_err(gettext("%s %s"), mnt_front, strerror(errno));
204 return (1);
205 }
206 }
207
208 /* if we do not know the name of the back file system mount point */
209 if (mnt_back[0] == '\0') {
210 /* all done */
211 return (0);
212 }
213
214 /*
215 * If the back file system was mounted on a directory with a
216 * parent name of BACKMNT_NAME then we assume that we
217 * mounted it and that it is okay to try to umount it.
218 */
219 if (strstr(mnt_back, BACKMNT_NAME) == NULL)
220 return (0);
221
222 /* if no back file system mounted */
223 if (strcmp(mnt_back, "nobackfs") == 0)
224 return (0);
225
226 /* fork */
227 if ((pid = fork()) == -1) {
228 pr_err(gettext("could not fork %s"), strerror(errno));
229 return (1);
230 }
231
232 /* if the child */
233 if (pid == 0) {
234 /* invoke the umount command on the back file system */
235 xx = execl("/sbin/umount", "/sbin/umount", mnt_back, NULL);
236 pr_err(gettext("could not exec /sbin/umount"
237 " on back file system %s"), strerror(errno));
238 }
239
240 /* else if the parent */
241 else {
242 /* wait for the child to exit */
243 if (wait(&stat_loc) == -1) {
244 pr_err(gettext("wait failed %s"), strerror(errno));
245 return (1);
246 }
247
248 if (!WIFEXITED(stat_loc)) {
249 pr_err(gettext("back umount did not exit"));
250 return (1);
251 }
252
253 xx = WEXITSTATUS(stat_loc);
254 if (xx) {
255 pr_err(gettext("back umount failed"));
256 return (xx);
257 }
258 }
259
260 /* delete the back file system mount point since we created it */
261 rmdir(mnt_back);
262
263 return (xx);
264 }
265
266 /*
267 *
268 * pr_err
269 *
270 * Description:
271 * Prints an error message to stderr.
272 * Arguments:
273 * fmt printf style format
274 * ... arguments for fmt
275 * Returns:
276 * Preconditions:
277 * precond(fmt)
278 */
279
280 void
281 pr_err(char *fmt, ...)
282 {
283 va_list ap;
284
285 va_start(ap, fmt);
286 (void) fprintf(stderr, gettext("umount -F cachefs: "));
287 (void) vfprintf(stderr, fmt, ap);
288 (void) fprintf(stderr, "\n");
289 va_end(ap);
290 }
291
292 /*
293 *
294 * usage
295 *
296 * Description:
297 * Prints a usage message.
298 * Arguments:
299 * An optional additional message to be displayed.
300 * Returns:
301 * Preconditions:
302 */
303
304 void
305 usage(char *msgp)
306 {
307 if (msgp)
308 pr_err(gettext("%s"), msgp);
309 fprintf(stderr, gettext("Usage: umount -F cachefs dir"));
310 }
311
312 /*
313 *
314 * daemon_unmount
315 *
316 * Description:
317 * Notifies the cachefsd of an unmount request.
318 * Arguments:
319 * Mount point to unmount.
320 * Returns:
321 * Returns 0 if the cachefsd unmounted the file system
322 * EIO if should try unmount directly
323 * EBUSY if did not unmount because busy
324 * EAGAIN if umounted but should not unmount nfs mount
325 *
326 * Preconditions:
327 * precond(mntptp)
328 */
329
330 int
331 daemon_unmount(char *mntptp, int flag)
332 {
333 CLIENT *clnt;
334 enum clnt_stat retval;
335 int xx;
336 int result;
337 char *hostp;
338 struct utsname info;
339 static struct timeval TIMEOUT = { 60*60, 0 };
340 static struct timeval create_timeout = { 5, 0};
341 struct cachefsd_fs_unmounted uargs;
342
343 /* get the host name */
344 xx = uname(&info);
345 if (xx == -1) {
346 pr_err(gettext("cannot get host name, errno %d"), errno);
347 return (EIO);
348 }
349 hostp = info.nodename;
350 uargs.mntpt = mntptp;
351 uargs.flag = flag;
352
353 /* creat the connection to the daemon */
354 clnt = clnt_create_timed(hostp, CACHEFSDPROG, CACHEFSDVERS, "local",
355 &create_timeout);
356 if (clnt == NULL) {
357 pr_err(gettext("cachefsd is not running"));
358 return (EIO);
359 }
360 clnt_control(clnt, CLSET_TIMEOUT, (char *)&TIMEOUT);
361
362 retval = cachefsd_fs_unmounted_1(&uargs, &result, clnt);
363 if (retval != RPC_SUCCESS) {
364 clnt_perror(clnt, gettext("cachefsd is not responding"));
365 clnt_destroy(clnt);
366 return (EIO);
367 }
368
369 clnt_destroy(clnt);
370
371 return (result);
372 }