2 * Copyright (c) 1997-2006 Erez Zadok
3 * Copyright (c) 1990 Jan-Simon Pendry
4 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1990 The Regents of the University of California.
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgment:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * File: am-utils/amd/amfs_toplvl.c
45 * Top-level file system
50 #endif /* HAVE_CONFIG_H */
54 /****************************************************************************
55 *** FORWARD DEFINITIONS ***
56 ****************************************************************************/
57 static int amfs_toplvl_init(mntfs *mf);
59 /****************************************************************************
60 *** OPS STRUCTURES ***
61 ****************************************************************************/
62 am_ops amfs_toplvl_ops =
66 amfs_toplvl_init, /* amfs_toplvl_init */
69 amfs_generic_lookup_child,
70 amfs_generic_mount_child,
72 0, /* amfs_toplvl_readlink */
74 0, /* amfs_toplvl_umounted */
75 amfs_generic_find_srvr,
76 0, /* amfs_toplvl_get_wchan */
77 FS_MKMNT | FS_NOTIMEOUT | FS_BACKGROUND |
78 FS_AMQINFO | FS_DIRECTORY, /* nfs_fs_flags */
80 AUTOFS_TOPLVL_FS_FLAGS,
81 #endif /* HAVE_FS_AUTOFS */
85 /****************************************************************************
87 ****************************************************************************/
90 set_auto_attrcache_timeout(char *preopts, char *opts, size_t l)
93 #ifdef MNTTAB_OPT_NOAC
95 * Don't cache attributes - they are changing under the kernel's feet.
96 * For example, IRIX5.2 will dispense with nfs lookup calls and hand stale
97 * filehandles to getattr unless we disable attribute caching on the
100 if (gopt.auto_attrcache == 0) {
101 xsnprintf(preopts, l, ",%s", MNTTAB_OPT_NOAC);
102 xstrlcat(opts, preopts, l);
104 #endif /* MNTTAB_OPT_NOAC */
107 * XXX: note that setting these to 0 in the past resulted in an error on
108 * some systems, which is why it's better to use "noac" if possible. For
109 * now, we're setting everything possible, but if this will cause trouble,
110 * then we'll have to condition the remainder of this on OPT_NOAC.
112 #ifdef MNTTAB_OPT_ACTIMEO
113 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTIMEO, gopt.auto_attrcache);
114 xstrlcat(opts, preopts, l);
115 #else /* MNTTAB_OPT_ACTIMEO */
116 # ifdef MNTTAB_OPT_ACDIRMIN
117 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTDIRMIN, gopt.auto_attrcache);
118 xstrlcat(opts, preopts, l);
119 # endif /* MNTTAB_OPT_ACDIRMIN */
120 # ifdef MNTTAB_OPT_ACDIRMAX
121 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTDIRMAX, gopt.auto_attrcache);
122 xstrlcat(opts, preopts, l);
123 # endif /* MNTTAB_OPT_ACDIRMAX */
124 # ifdef MNTTAB_OPT_ACREGMIN
125 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTREGMIN, gopt.auto_attrcache);
126 xstrlcat(opts, preopts, l);
127 # endif /* MNTTAB_OPT_ACREGMIN */
128 # ifdef MNTTAB_OPT_ACREGMAX
129 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTREGMAX, gopt.auto_attrcache);
130 xstrlcat(opts, preopts, l);
131 # endif /* MNTTAB_OPT_ACREGMAX */
132 #endif /* MNTTAB_OPT_ACTIMEO */
137 * Initialize a top-level mount. In our case, if the user asked for
138 * forced_unmounts, and the OS supports it, then we try forced/lazy unmounts
139 * on any previous toplvl mounts. This is useful if a previous Amd died and
140 * left behind toplvl mount points (this Amd will clean them up).
142 * WARNING: Don't use forced/lazy unmounts if you have another valid Amd
143 * running, because this code WILL force those valid toplvl mount points to
144 * be detached as well!
147 amfs_toplvl_init(mntfs *mf)
151 #if defined(MNT2_GEN_OPT_FORCE) || defined(MNT2_GEN_OPT_DETACH)
152 if (gopt.flags & CFM_FORCED_UNMOUNTS) {
153 plog(XLOG_INFO, "amfs_toplvl_init: trying forced/lazy unmount of %s",
155 error = umount2_fs(mf->mf_mount, AMU_UMOUNT_FORCE | AMU_UMOUNT_DETACH);
157 plog(XLOG_INFO, "amfs_toplvl_init: forced/lazy unmount failed: %m");
159 dlog("amfs_toplvl_init: forced/lazy unmount succeeded");
161 #endif /* MNT2_GEN_OPT_FORCE || MNT2_GEN_OPT_DETACH */
167 * Mount the top-level
170 amfs_toplvl_mount(am_node *mp, mntfs *mf)
173 char opts[SIZEOF_OPTS], preopts[SIZEOF_OPTS], toplvl_opts[40];
177 * Mounting the automounter.
178 * Make sure the mount directory exists, construct
179 * the mount options and call the mount_amfs_toplvl routine.
182 if (stat(mp->am_path, &stb) < 0) {
184 } else if ((stb.st_mode & S_IFMT) != S_IFDIR) {
185 plog(XLOG_WARNING, "%s is not a directory", mp->am_path);
190 * Construct some mount options:
192 * Tack on magic map=<mapname> option in mtab to emulate
193 * SunOS automounter behavior.
196 #ifdef HAVE_FS_AUTOFS
197 if (mf->mf_flags & MFF_IS_AUTOFS) {
198 autofs_get_opts(opts, sizeof(opts), mp->am_autofs_fh);
200 #endif /* HAVE_FS_AUTOFS */
203 #ifdef MNTTAB_OPT_INTR
204 xstrlcat(preopts, MNTTAB_OPT_INTR, sizeof(preopts));
205 xstrlcat(preopts, ",", sizeof(preopts));
206 #endif /* MNTTAB_OPT_INTR */
207 #ifdef MNTTAB_OPT_IGNORE
208 xstrlcat(preopts, MNTTAB_OPT_IGNORE, sizeof(preopts));
209 xstrlcat(preopts, ",", sizeof(preopts));
210 #endif /* MNTTAB_OPT_IGNORE */
211 /* write most of the initial options + preopts */
212 xsnprintf(opts, sizeof(opts), "%s%s,%s=%d,%s,map=%s",
215 MNTTAB_OPT_PORT, nfs_port,
216 mf->mf_ops->fs_type, mf->mf_info);
218 /* process toplvl timeo/retrans options, if any */
219 if (gopt.amfs_auto_timeo[AMU_TYPE_TOPLVL] > 0) {
220 xsnprintf(toplvl_opts, sizeof(toplvl_opts), ",%s=%d",
221 MNTTAB_OPT_TIMEO, gopt.amfs_auto_timeo[AMU_TYPE_TOPLVL]);
222 xstrlcat(opts, toplvl_opts, sizeof(opts));
224 if (gopt.amfs_auto_retrans[AMU_TYPE_TOPLVL] > 0) {
225 xsnprintf(toplvl_opts, sizeof(toplvl_opts), ",%s=%d",
226 MNTTAB_OPT_RETRANS, gopt.amfs_auto_retrans[AMU_TYPE_TOPLVL]);
227 xstrlcat(opts, toplvl_opts, sizeof(opts));
230 #ifdef MNTTAB_OPT_NOAC
231 if (gopt.auto_attrcache == 0) {
232 xstrlcat(opts, ",", sizeof(opts));
233 xstrlcat(opts, MNTTAB_OPT_NOAC, sizeof(opts));
235 #endif /* MNTTAB_OPT_NOAC */
236 set_auto_attrcache_timeout(preopts, opts, sizeof(preopts));
239 /* now do the mount */
240 error = amfs_mount(mp, mf, opts);
243 plog(XLOG_FATAL, "amfs_toplvl_mount: amfs_mount failed: %m");
251 * Unmount a top-level automount node
254 amfs_toplvl_umount(am_node *mp, mntfs *mf)
257 int unmount_flags = (mf->mf_flags & MFF_ON_AUTOFS) ? AMU_UMOUNT_AUTOFS : 0;
259 int count = 0; /* how many times did we try to unmount? */
263 * The lstat is needed if this mount is type=direct.
264 * When that happens, the kernel cache gets confused
265 * between the underlying type (dir) and the mounted
266 * type (link) and so needs to be re-synced before
267 * the unmount. This is all because the unmount system
268 * call follows links and so can't actually unmount
269 * a link (stupid!). It was noted that doing an ls -ld
270 * of the mount point to see why things were not working
271 * actually fixed the problem - so simulate an ls -ld here.
273 if (lstat(mp->am_path, &stb) < 0) {
275 dlog("lstat(%s): %m", mp->am_path);
278 if ((stb.st_mode & S_IFMT) != S_IFDIR) {
279 plog(XLOG_ERROR, "amfs_toplvl_umount: %s is not a directory, aborting.", mp->am_path);
284 error = UMOUNT_FS(mp->am_path, mnttab_file_name, unmount_flags);
285 if (error == EBUSY) {
286 #ifdef HAVE_FS_AUTOFS
288 * autofs mounts are "in place", so it is possible
289 * that we can't just unmount our mount points and go away.
290 * If that's the case, just give up.
292 if (mf->mf_flags & MFF_IS_AUTOFS)
294 #endif /* HAVE_FS_AUTOFS */
295 plog(XLOG_WARNING, "amfs_toplvl_unmount retrying %s in 1s", mp->am_path);
299 * If user wants forced/lazy unmount semantics, then set those flags,
300 * but only after we've tried normal lstat/umount a few times --
301 * otherwise forced unmounts may hang this very same Amd (by preventing
302 * it from achieving a clean unmount).
304 if (gopt.flags & CFM_FORCED_UNMOUNTS) {
305 if (count == 5) { /* after 5 seconds, try MNT_FORCE */
306 dlog("enabling forced unmounts for toplvl node %s", mp->am_path);
307 unmount_flags |= AMU_UMOUNT_FORCE;
309 if (count == 10) { /* after 10 seconds, try MNT_DETACH */
310 dlog("enabling detached unmounts for toplvl node %s", mp->am_path);
311 unmount_flags |= AMU_UMOUNT_DETACH;