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 */
57static qelem amfs_auto_srvr_list = {&amfs_auto_srvr_list, &amfs_auto_srvr_list};
58static fserver *localhost;
59
60
61/*
62 * Find an nfs server for the local host
63 */
64fserver *
65amfs_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 */
100void
101wakeup_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 */
111static void
112timeout_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 */
157void
158free_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 */
195fserver *
196dup_srvr(fserver *fs)
197{
198  fs->fs_refc++;
199  return fs;
200}
201
202
203/*
204 * Log state change
205 */
206void
207srvrlog(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