external/bsd/am-utils/dist/amd/srvr_amfs_auto.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1997-2009 Erez Zadok
   5  * Copyright (c) 1989 Jan-Simon Pendry
   6  * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
   7  * Copyright (c) 1989 The Regents of the University of California.
   8  * All rights reserved.
   9  *
  10  * This code is derived from software contributed to Berkeley by
  11  * Jan-Simon Pendry at Imperial College, London.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. All advertising materials mentioning features or use of this software
  22  *    must display the following acknowledgment:
  23  *      This product includes software developed by the University of
  24  *      California, Berkeley and its contributors.
  25  * 4. Neither the name of the University nor the names of its contributors
  26  *    may be used to endorse or promote products derived from this software
  27  *    without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  39  * SUCH DAMAGE.
  40  *
  41  *
  42  * File: am-utils/amd/srvr_amfs_auto.c
  43  *
  44  */
  45
  46 /*
  47  * Automount FS server ("localhost") modeling
  48  */
  49
  50 #ifdef HAVE_CONFIG_H
  51 # include <config.h>
  52 #endif /* HAVE_CONFIG_H */
  53 #include <am_defs.h>
  54 #include <amd.h>
  55
  56 /* globals */
  57
  58 /* statics */
  59 static qelem amfs_auto_srvr_list = {&amfs_auto_srvr_list, &amfs_auto_srvr_list};
  60 static fserver *localhost;
  61
  62
  63 /*
  64  * Find an nfs server for the local host
  65  */
  66 fserver *
  67 amfs_generic_find_srvr(mntfs *mf)
  68 {
  69   fserver *fs = localhost;
  70
  71   if (!fs) {
  72     fs = ALLOC(struct fserver);
  73     fs->fs_refc = 0;
  74     fs->fs_host = strdup("localhost");
  75     fs->fs_ip = NULL;
  76     fs->fs_cid = 0;
  77     fs->fs_pinger = AM_PINGER;
  78     fs->fs_flags = FSF_VALID | FSF_PING_UNINIT;
  79     fs->fs_type = "local";
  80     fs->fs_private = NULL;
  81     fs->fs_prfree = NULL;
  82
  83     ins_que(&fs->fs_q, &amfs_auto_srvr_list);
  84
  85     srvrlog(fs, "starts up");
  86
  87     localhost = fs;
  88   }
  89   fs->fs_refc++;
  90
  91   return fs;
  92 }
  93
  94
  95 /*****************************************************************************
  96  *** GENERIC ROUTINES FOLLOW
  97  *****************************************************************************/
  98
  99 /*
 100  * Wakeup anything waiting for this server
 101  */
 102 void
 103 wakeup_srvr(fserver *fs)
 104 {
 105   fs->fs_flags &= ~FSF_WANT;
 106   wakeup((voidp) fs);
 107 }
 108
 109
 110 /*
 111  * Called when final ttl of server has expired
 112  */
 113 static void
 114 timeout_srvr(voidp v)
 115 {
 116   fserver *fs = v;
 117
 118   /*
 119    * If the reference count is still zero then
 120    * we are free to remove this node
 121    */
 122   if (fs->fs_refc == 0) {
 123     dlog("Deleting file server %s", fs->fs_host);
 124     if (fs->fs_flags & FSF_WANT)
 125       wakeup_srvr(fs);
 126
 127     /*
 128      * Remove from queue.
 129      */
 130     rem_que(&fs->fs_q);
 131     /*
 132      * (Possibly) call the private free routine.
 133      */
 134     if (fs->fs_private && fs->fs_prfree)
 135       (*fs->fs_prfree) (fs->fs_private);
 136
 137     /*
 138      * Free the net address
 139      */
 140     if (fs->fs_ip)
 141       XFREE(fs->fs_ip);
 142
 143     /*
 144      * Free the host name.
 145      */
 146     XFREE(fs->fs_host);
 147
 148     /*
 149      * Discard the fserver object.
 150      */
 151     XFREE(fs);
 152   }
 153 }
 154
 155
 156 /*
 157  * Free a file server
 158  */
 159 void
 160 free_srvr(fserver *fs)
 161 {
 162   if (--fs->fs_refc == 0) {
 163     /*
 164      * The reference count is now zero,
 165      * so arrange for this node to be
 166      * removed in AM_TTL seconds if no
 167      * other mntfs is referencing it.
 168      */
 169     int ttl = (FSRV_ERROR(fs) || FSRV_ISDOWN(fs)) ? 19 : AM_TTL;
 170
 171     dlog("Last hard reference to file server %s - will timeout in %ds", fs->fs_host, ttl);
 172     if (fs->fs_cid) {
 173       untimeout(fs->fs_cid);
 174       /*
 175        * Turn off pinging - XXX
 176        */
 177       fs->fs_flags &= ~FSF_PINGING;
 178     }
 179
 180     /*
 181      * Keep structure lying around for a while
 182      */
 183     fs->fs_cid = timeout(ttl, timeout_srvr, (voidp) fs);
 184
 185     /*
 186      * Mark the fileserver down and invalid again
 187      */
 188     fs->fs_flags &= ~FSF_VALID;
 189     fs->fs_flags |= FSF_DOWN;
 190   }
 191 }
 192
 193
 194 /*
 195  * Make a duplicate fserver reference
 196  */
 197 fserver *
 198 dup_srvr(fserver *fs)
 199 {
 200   fs->fs_refc++;
 201   return fs;
 202 }
 203
 204
 205 /*
 206  * Log state change
 207  */
 208 void
 209 srvrlog(fserver *fs, char *state)
 210 {
 211   plog(XLOG_INFO, "file server %s, type %s, state %s", fs->fs_host, fs->fs_type, state);
 212 }