2 * Copyright (c) 1997-2014 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. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * File: am-utils/amd/amfs_toplvl.c
41 * Top-level file system
46 #endif /* HAVE_CONFIG_H */
50 /****************************************************************************
51 *** FORWARD DEFINITIONS ***
52 ****************************************************************************/
53 static int amfs_toplvl_init(mntfs *mf);
55 /****************************************************************************
56 *** OPS STRUCTURES ***
57 ****************************************************************************/
58 am_ops amfs_toplvl_ops =
62 amfs_toplvl_init, /* amfs_toplvl_init */
65 amfs_generic_lookup_child,
66 amfs_generic_mount_child,
68 0, /* amfs_toplvl_readlink */
70 0, /* amfs_toplvl_umounted */
71 amfs_generic_find_srvr,
72 0, /* amfs_toplvl_get_wchan */
73 FS_MKMNT | FS_NOTIMEOUT | FS_BACKGROUND |
74 FS_AMQINFO | FS_DIRECTORY, /* nfs_fs_flags */
76 AUTOFS_TOPLVL_FS_FLAGS,
77 #endif /* HAVE_FS_AUTOFS */
81 /****************************************************************************
83 ****************************************************************************/
86 set_auto_attrcache_timeout(char *preopts, char *opts, size_t l)
89 #ifdef MNTTAB_OPT_NOAC
91 * Don't cache attributes - they are changing under the kernel's feet.
92 * For example, IRIX5.2 will dispense with nfs lookup calls and hand stale
93 * filehandles to getattr unless we disable attribute caching on the
96 if (gopt.auto_attrcache == 0) {
97 xsnprintf(preopts, l, ",%s", MNTTAB_OPT_NOAC);
98 xstrlcat(opts, preopts, l);
100 #endif /* MNTTAB_OPT_NOAC */
103 * XXX: note that setting these to 0 in the past resulted in an error on
104 * some systems, which is why it's better to use "noac" if possible. For
105 * now, we're setting everything possible, but if this will cause trouble,
106 * then we'll have to condition the remainder of this on OPT_NOAC.
108 #ifdef MNTTAB_OPT_ACTIMEO
109 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTIMEO, gopt.auto_attrcache);
110 xstrlcat(opts, preopts, l);
111 #else /* MNTTAB_OPT_ACTIMEO */
112 # ifdef MNTTAB_OPT_ACDIRMIN
113 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTDIRMIN, gopt.auto_attrcache);
114 xstrlcat(opts, preopts, l);
115 # endif /* MNTTAB_OPT_ACDIRMIN */
116 # ifdef MNTTAB_OPT_ACDIRMAX
117 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTDIRMAX, gopt.auto_attrcache);
118 xstrlcat(opts, preopts, l);
119 # endif /* MNTTAB_OPT_ACDIRMAX */
120 # ifdef MNTTAB_OPT_ACREGMIN
121 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTREGMIN, gopt.auto_attrcache);
122 xstrlcat(opts, preopts, l);
123 # endif /* MNTTAB_OPT_ACREGMIN */
124 # ifdef MNTTAB_OPT_ACREGMAX
125 xsnprintf(preopts, l, ",%s=%d", MNTTAB_OPT_ACTREGMAX, gopt.auto_attrcache);
126 xstrlcat(opts, preopts, l);
127 # endif /* MNTTAB_OPT_ACREGMAX */
128 #endif /* MNTTAB_OPT_ACTIMEO */
133 * Initialize a top-level mount. In our case, if the user asked for
134 * forced_unmounts, and the OS supports it, then we try forced/lazy unmounts
135 * on any previous toplvl mounts. This is useful if a previous Amd died and
136 * left behind toplvl mount points (this Amd will clean them up).
138 * WARNING: Don't use forced/lazy unmounts if you have another valid Amd
139 * running, because this code WILL force those valid toplvl mount points to
140 * be detached as well!
143 amfs_toplvl_init(mntfs *mf)
147 #if (defined(MNT2_GEN_OPT_FORCE) || defined(MNT2_GEN_OPT_DETACH)) && (defined(HAVE_UVMOUNT) || defined(HAVE_UMOUNT2))
148 if (gopt.flags & CFM_FORCED_UNMOUNTS) {
149 plog(XLOG_INFO, "amfs_toplvl_init: trying forced/lazy unmount of %s",
151 error = umount2_fs(mf->mf_mount, AMU_UMOUNT_FORCE | AMU_UMOUNT_DETACH);
153 plog(XLOG_INFO, "amfs_toplvl_init: forced/lazy unmount failed: %m");
155 dlog("amfs_toplvl_init: forced/lazy unmount succeeded");
157 #endif /* (MNT2_GEN_OPT_FORCE || MNT2_GEN_OPT_DETACH) && (HAVE_UVMOUNT || HAVE_UMOUNT2) */
163 * Mount the top-level
166 amfs_toplvl_mount(am_node *mp, mntfs *mf)
169 char opts[SIZEOF_OPTS], preopts[SIZEOF_OPTS], toplvl_opts[40];
173 * Mounting the automounter.
174 * Make sure the mount directory exists, construct
175 * the mount options and call the mount_amfs_toplvl routine.
178 if (stat(mp->am_path, &stb) < 0) {
180 } else if ((stb.st_mode & S_IFMT) != S_IFDIR) {
181 plog(XLOG_WARNING, "%s is not a directory", mp->am_path);
186 * Construct some mount options:
188 * Tack on magic map=<mapname> option in mtab to emulate
189 * SunOS automounter behavior.
192 #ifdef HAVE_FS_AUTOFS
193 if (mf->mf_flags & MFF_IS_AUTOFS) {
194 autofs_get_opts(opts, sizeof(opts), mp->am_autofs_fh);
196 #endif /* HAVE_FS_AUTOFS */
199 #ifdef MNTTAB_OPT_INTR
200 xstrlcat(preopts, MNTTAB_OPT_INTR, sizeof(preopts));
201 xstrlcat(preopts, ",", sizeof(preopts));
202 #endif /* MNTTAB_OPT_INTR */
203 #ifdef MNTTAB_OPT_IGNORE
204 xstrlcat(preopts, MNTTAB_OPT_IGNORE, sizeof(preopts));
205 xstrlcat(preopts, ",", sizeof(preopts));
206 #endif /* MNTTAB_OPT_IGNORE */
207 /* write most of the initial options + preopts */
208 xsnprintf(opts, sizeof(opts), "%s%s,%s=%d,%s,map=%s",
211 MNTTAB_OPT_PORT, nfs_port,
212 mf->mf_ops->fs_type, mf->mf_info);
214 /* process toplvl timeo/retrans options, if any */
215 if (gopt.amfs_auto_timeo[AMU_TYPE_TOPLVL] > 0) {
216 xsnprintf(toplvl_opts, sizeof(toplvl_opts), ",%s=%d",
217 MNTTAB_OPT_TIMEO, gopt.amfs_auto_timeo[AMU_TYPE_TOPLVL]);
218 xstrlcat(opts, toplvl_opts, sizeof(opts));
220 if (gopt.amfs_auto_retrans[AMU_TYPE_TOPLVL] > 0) {
221 xsnprintf(toplvl_opts, sizeof(toplvl_opts), ",%s=%d",
222 MNTTAB_OPT_RETRANS, gopt.amfs_auto_retrans[AMU_TYPE_TOPLVL]);
223 xstrlcat(opts, toplvl_opts, sizeof(opts));
226 #ifdef MNTTAB_OPT_NOLOCK
227 xstrlcat(opts, ",", sizeof(opts));
228 xstrlcat(opts, MNTTAB_OPT_NOLOCK, sizeof(opts));
229 #endif /* MNTTAB_OPT_NOLOCK */
231 #ifdef MNTTAB_OPT_NOAC
232 if (gopt.auto_attrcache == 0) {
233 xstrlcat(opts, ",", sizeof(opts));
234 xstrlcat(opts, MNTTAB_OPT_NOAC, sizeof(opts));
236 #endif /* MNTTAB_OPT_NOAC */
237 set_auto_attrcache_timeout(preopts, opts, sizeof(preopts));
240 /* now do the mount */
241 error = amfs_mount(mp, mf, opts);
244 plog(XLOG_FATAL, "amfs_toplvl_mount: amfs_mount failed: %m");
252 * Unmount a top-level automount node
255 amfs_toplvl_umount(am_node *mp, mntfs *mf)
258 int unmount_flags = (mf->mf_flags & MFF_ON_AUTOFS) ? AMU_UMOUNT_AUTOFS : 0;
260 int count = 0; /* how many times did we try to unmount? */
264 * The lstat is needed if this mount is type=direct.
265 * When that happens, the kernel cache gets confused
266 * between the underlying type (dir) and the mounted
267 * type (link) and so needs to be re-synced before
268 * the unmount. This is all because the unmount system
269 * call follows links and so can't actually unmount
270 * a link (stupid!). It was noted that doing an ls -ld
271 * of the mount point to see why things were not working
272 * actually fixed the problem - so simulate an ls -ld here.
274 if (lstat(mp->am_path, &stb) < 0) {
276 dlog("lstat(%s): %m", mp->am_path);
279 if ((stb.st_mode & S_IFMT) != S_IFDIR) {
280 plog(XLOG_ERROR, "amfs_toplvl_umount: %s is not a directory, aborting.", mp->am_path);
285 error = UMOUNT_FS(mp->am_path, mnttab_file_name, unmount_flags);
286 if (error == EBUSY) {
287 #ifdef HAVE_FS_AUTOFS
289 * autofs mounts are "in place", so it is possible
290 * that we can't just unmount our mount points and go away.
291 * If that's the case, just give up.
293 if (mf->mf_flags & MFF_IS_AUTOFS)
295 #endif /* HAVE_FS_AUTOFS */
296 plog(XLOG_WARNING, "amfs_toplvl_unmount retrying %s in 1s", mp->am_path);
300 * If user wants forced/lazy unmount semantics, then set those flags,
301 * but only after we've tried normal lstat/umount a few times --
302 * otherwise forced unmounts may hang this very same Amd (by preventing
303 * it from achieving a clean unmount).
305 if (gopt.flags & CFM_FORCED_UNMOUNTS) {
306 if (count == 5) { /* after 5 seconds, try MNT_FORCE */
307 dlog("enabling forced unmounts for toplvl node %s", mp->am_path);
308 unmount_flags |= AMU_UMOUNT_FORCE;
310 if (count == 10) { /* after 10 seconds, try MNT_DETACH */
311 dlog("enabling detached unmounts for toplvl node %s", mp->am_path);
312 unmount_flags |= AMU_UMOUNT_DETACH;