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 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 #include <dirent.h>
27 #include <stdlib.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <synch.h>
31 #include <unistd.h>
32 #include <sys/errno.h>
33 #include <sys/types.h>
34 #include <sys/stat.h>
35 #include <sys/vfstab.h>
36 #include <fcntl.h>
37 #include <sys/wait.h>
38 #include <sys/fs/ufs_fs.h>
39
40 #include "libdiskmgt.h"
41 #include "disks_private.h"
42
43 /*
44 * The list of filesystem heuristic programs.
45 */
46 struct heuristic {
47 struct heuristic *next;
48 char *prog;
49 char *type;
50 };
51
52 struct vfstab_list {
53 char *special;
54 char *mountp;
55 struct vfstab_list *next;
56 };
57
58 static struct vfstab_list *vfstab_listp = NULL;
59 static mutex_t vfstab_lock = DEFAULTMUTEX;
60
61 static time_t timestamp = 0;
62
63 static struct heuristic *hlist = NULL;
64 static int initialized = 0;
65 static mutex_t init_lock = DEFAULTMUTEX;
66
67 static int has_fs(char *prog, char *slice);
68 static int load_heuristics();
69 static int add_use_record(struct vfstab *vp);
70 static int load_vfstab();
71 static void free_vfstab(struct vfstab_list *listp);
72
73 /*
74 * Use the heuristics to check for a filesystem on the slice.
75 */
76 int
inuse_fs(char * slice,nvlist_t * attrs,int * errp)77 inuse_fs(char *slice, nvlist_t *attrs, int *errp)
78 {
79 struct heuristic *hp;
80 time_t curr_time;
81 int found = 0;
82
83
84 *errp = 0;
85
86 if (slice == NULL) {
87 return (0);
88 }
89
90 /*
91 * We get the list of heuristic programs one time.
92 */
93 (void) mutex_lock(&init_lock);
94 if (!initialized) {
95 *errp = load_heuristics();
96
97 if (*errp == 0) {
98 initialized = 1;
99 }
100 }
101 (void) mutex_unlock(&init_lock);
102
103 /* Run each of the heuristics. */
104 for (hp = hlist; hp; hp = hp->next) {
105 if (has_fs(hp->prog, slice)) {
106 libdiskmgt_add_str(attrs, DM_USED_BY, DM_USE_FS, errp);
107 libdiskmgt_add_str(attrs, DM_USED_NAME, hp->type, errp);
108 found = 1;
109 }
110 }
111
112 if (*errp != 0)
113 return (found);
114
115 /*
116 * Second heuristic used is the check for an entry in vfstab
117 */
118
119 (void) mutex_lock(&vfstab_lock);
120 curr_time = time(NULL);
121
122 if (timestamp < curr_time && (curr_time - timestamp) > 60) {
123 free_vfstab(vfstab_listp);
124 *errp = load_vfstab();
125 timestamp = curr_time;
126 }
127
128 if (*errp == 0) {
129 struct vfstab_list *listp;
130 listp = vfstab_listp;
131
132 while (listp != NULL) {
133 if (strcmp(slice, listp->special) == 0) {
134 char *mountp = "";
135
136 if (listp->mountp != NULL)
137 mountp = listp->mountp;
138
139 libdiskmgt_add_str(attrs, DM_USED_BY, DM_USE_VFSTAB, errp);
140 libdiskmgt_add_str(attrs, DM_USED_NAME, mountp, errp);
141 found = 1;
142 }
143 listp = listp->next;
144 }
145 }
146 (void) mutex_unlock(&vfstab_lock);
147 return (found);
148 }
149
150 static int
has_fs(char * prog,char * slice)151 has_fs(char *prog, char *slice)
152 {
153 pid_t pid;
154 int loc;
155 mode_t mode = S_IRUSR | S_IWUSR;
156
157 switch ((pid = fork1())) {
158 case 0:
159 /* child process */
160
161 closefrom(1);
162 (void) open("/dev/null", O_WRONLY, mode);
163 (void) open("/dev/null", O_WRONLY, mode);
164 (void) execl(prog, "fstyp", slice, NULL);
165 _exit(1);
166 break;
167
168 case -1:
169 return (0);
170
171 default:
172 /* parent process */
173 break;
174 }
175
176 (void) waitpid(pid, &loc, 0);
177
178 if (WIFEXITED(loc) && WEXITSTATUS(loc) == 0) {
179 return (1);
180 }
181
182 return (0);
183 }
184
185 /*
186 * Create a list of filesystem heuristic programs.
187 */
188 static int
load_heuristics()189 load_heuristics()
190 {
191 DIR *dirp;
192
193 if ((dirp = opendir("/usr/lib/fs")) != NULL) {
194 struct dirent *dp;
195
196 while ((dp = readdir(dirp)) != NULL) {
197 char path[MAXPATHLEN];
198 struct stat buf;
199 DIR *subdirp;
200
201 /* skip known dirs */
202 if (strcmp(dp->d_name, ".") == 0 ||
203 strcmp(dp->d_name, "..") == 0) {
204 continue;
205 }
206
207 /*
208 * Skip checking for ZFS filesystems. We know that
209 * inuse_zpool() will have already been called, which does a
210 * better job of checking anyway. More importantly, an unused
211 * hot spare will still claim to have a ZFS filesystem because
212 * it doesn't do the same level of checks.
213 */
214 if (strcmp(dp->d_name, "zfs") == 0)
215 continue;
216
217 (void) snprintf(path, sizeof (path), "/usr/lib/fs/%s",
218 dp->d_name);
219
220 if (stat(path, &buf) != 0 || !S_ISDIR(buf.st_mode)) {
221 continue;
222 }
223
224 if ((subdirp = opendir(path)) != NULL) {
225 struct dirent *sdp;
226
227 while ((sdp = readdir(subdirp)) != NULL) {
228
229 if (strcmp(sdp->d_name, "fstyp") == 0) {
230 char progpath[MAXPATHLEN];
231
232 (void) snprintf(progpath, sizeof (progpath),
233 "/usr/lib/fs/%s/fstyp", dp->d_name);
234
235 if (stat(progpath, &buf) == 0 &&
236 S_ISREG(buf.st_mode)) {
237
238 struct heuristic *hp;
239
240 hp = (struct heuristic *)
241 malloc(sizeof (struct heuristic));
242
243 if (hp == NULL) {
244 (void) closedir(subdirp);
245 (void) closedir(dirp);
246 return (ENOMEM);
247 }
248
249 if ((hp->prog = strdup(progpath)) == NULL) {
250 (void) closedir(subdirp);
251 (void) closedir(dirp);
252 return (ENOMEM);
253 }
254
255 if ((hp->type = strdup(dp->d_name)) == NULL) {
256 (void) closedir(subdirp);
257 (void) closedir(dirp);
258 return (ENOMEM);
259 }
260
261 hp->next = hlist;
262 hlist = hp;
263 }
264
265 break;
266 }
267 }
268
269 (void) closedir(subdirp);
270 }
271 }
272
273 (void) closedir(dirp);
274 }
275
276 return (0);
277 }
278
279 static int
load_vfstab()280 load_vfstab()
281 {
282 FILE *fp;
283 struct vfstab vp;
284 int status = 1;
285
286 fp = fopen(VFSTAB, "r");
287 if (fp != NULL) {
288 (void) memset(&vp, 0, sizeof (struct vfstab));
289 while (getvfsent(fp, &vp) == 0) {
290 status = add_use_record(&vp);
291 if (status != 0) {
292 (void) fclose(fp);
293 return (status);
294 }
295 (void) memset(&vp, 0, sizeof (struct vfstab));
296 }
297 (void) fclose(fp);
298 status = 0;
299 }
300
301 return (status);
302 }
303
304 static int
add_use_record(struct vfstab * vp)305 add_use_record(struct vfstab *vp)
306 {
307 struct vfstab_list *vfsp;
308
309 vfsp = (struct vfstab_list *)malloc(sizeof (struct vfstab_list));
310 if (vfsp == NULL) {
311 return (ENOMEM);
312 }
313
314 vfsp->special = strdup(vp->vfs_special);
315 if (vfsp->special == NULL) {
316 free(vfsp);
317 return (ENOMEM);
318 }
319
320 if (vp->vfs_mountp != NULL) {
321 vfsp->mountp = strdup(vp->vfs_mountp);
322 if (vfsp->mountp == NULL) {
323 free(vfsp);
324 return (ENOMEM);
325 }
326 } else {
327 vfsp->mountp = NULL;
328 }
329
330 vfsp->next = vfstab_listp;
331 vfstab_listp = vfsp;
332
333 return (0);
334 }
335
336 static void
free_vfstab(struct vfstab_list * listp)337 free_vfstab(struct vfstab_list *listp)
338 {
339 struct vfstab_list *nextp;
340
341 while (listp != NULL) {
342 nextp = listp->next;
343 free((void *)listp->special);
344 free((void *)listp->mountp);
345 free((void *)listp);
346 listp = nextp;
347 }
348
349 vfstab_listp = NULL;
350 }
351