1 /*
2 * Copyright (c) 1997-2006 Erez Zadok
3 * Copyright (c) 1989 Jan-Simon Pendry
4 * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1989 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
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.
26 *
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
37 * SUCH DAMAGE.
38 *
39 *
40 * File: am-utils/amd/srvr_amfs_auto.c
41 *
42 */
43
44 /*
45 * Automount FS server ("localhost") modeling
46 */
47
48 #ifdef HAVE_CONFIG_H
49 # include <config.h>
50 #endif /* HAVE_CONFIG_H */
51 #include <am_defs.h>
52 #include <amd.h>
53
54 /* globals */
55
56 /* statics */
57 static qelem amfs_auto_srvr_list = {&amfs_auto_srvr_list, &amfs_auto_srvr_list};
58 static fserver *localhost;
59
60
61 /*
62 * Find an nfs server for the local host
63 */
64 fserver *
amfs_generic_find_srvr(mntfs * mf)65 amfs_generic_find_srvr(mntfs *mf)
66 {
67 fserver *fs = localhost;
68
69 if (!fs) {
70 fs = ALLOC(struct fserver);
71 fs->fs_refc = 0;
72 fs->fs_host = strdup("localhost");
73 fs->fs_ip = 0;
74 fs->fs_cid = 0;
75 fs->fs_pinger = AM_PINGER;
76 fs->fs_flags = FSF_VALID | FSF_PING_UNINIT;
77 fs->fs_type = "local";
78 fs->fs_private = 0;
79 fs->fs_prfree = 0;
80
81 ins_que(&fs->fs_q, &amfs_auto_srvr_list);
82
83 srvrlog(fs, "starts up");
84
85 localhost = fs;
86 }
87 fs->fs_refc++;
88
89 return fs;
90 }
91
92
93 /*****************************************************************************
94 *** GENERIC ROUTINES FOLLOW
95 *****************************************************************************/
96
97 /*
98 * Wakeup anything waiting for this server
99 */
100 void
wakeup_srvr(fserver * fs)101 wakeup_srvr(fserver *fs)
102 {
103 fs->fs_flags &= ~FSF_WANT;
104 wakeup((voidp) fs);
105 }
106
107
108 /*
109 * Called when final ttl of server has expired
110 */
111 static void
timeout_srvr(voidp v)112 timeout_srvr(voidp v)
113 {
114 fserver *fs = v;
115
116 /*
117 * If the reference count is still zero then
118 * we are free to remove this node
119 */
120 if (fs->fs_refc == 0) {
121 dlog("Deleting file server %s", fs->fs_host);
122 if (fs->fs_flags & FSF_WANT)
123 wakeup_srvr(fs);
124
125 /*
126 * Remove from queue.
127 */
128 rem_que(&fs->fs_q);
129 /*
130 * (Possibly) call the private free routine.
131 */
132 if (fs->fs_private && fs->fs_prfree)
133 (*fs->fs_prfree) (fs->fs_private);
134
135 /*
136 * Free the net address
137 */
138 if (fs->fs_ip)
139 XFREE(fs->fs_ip);
140
141 /*
142 * Free the host name.
143 */
144 XFREE(fs->fs_host);
145
146 /*
147 * Discard the fserver object.
148 */
149 XFREE(fs);
150 }
151 }
152
153
154 /*
155 * Free a file server
156 */
157 void
free_srvr(fserver * fs)158 free_srvr(fserver *fs)
159 {
160 if (--fs->fs_refc == 0) {
161 /*
162 * The reference count is now zero,
163 * so arrange for this node to be
164 * removed in AM_TTL seconds if no
165 * other mntfs is referencing it.
166 */
167 int ttl = (FSRV_ERROR(fs) || FSRV_ISDOWN(fs)) ? 19 : AM_TTL;
168
169 dlog("Last hard reference to file server %s - will timeout in %ds", fs->fs_host, ttl);
170 if (fs->fs_cid) {
171 untimeout(fs->fs_cid);
172 /*
173 * Turn off pinging - XXX
174 */
175 fs->fs_flags &= ~FSF_PINGING;
176 }
177
178 /*
179 * Keep structure lying around for a while
180 */
181 fs->fs_cid = timeout(ttl, timeout_srvr, (voidp) fs);
182
183 /*
184 * Mark the fileserver down and invalid again
185 */
186 fs->fs_flags &= ~FSF_VALID;
187 fs->fs_flags |= FSF_DOWN;
188 }
189 }
190
191
192 /*
193 * Make a duplicate fserver reference
194 */
195 fserver *
dup_srvr(fserver * fs)196 dup_srvr(fserver *fs)
197 {
198 fs->fs_refc++;
199 return fs;
200 }
201
202
203 /*
204 * Log state change
205 */
206 void
srvrlog(fserver * fs,char * state)207 srvrlog(fserver *fs, char *state)
208 {
209 plog(XLOG_INFO, "file server %s, type %s, state %s", fs->fs_host, fs->fs_type, state);
210 }
211