1/* 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. 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/amfs_union.c 41 * 42 */ 43 44/* 45 * Union automounter file system 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/**************************************************************************** 55 *** FORWARD DEFINITIONS *** 56 ****************************************************************************/ 57static int create_amfs_union_node(char *dir, opaque_t arg); 58static void amfs_union_mounted(mntfs *mf); 59 60 61/**************************************************************************** 62 *** OPS STRUCTURES *** 63 ****************************************************************************/ 64am_ops amfs_union_ops = 65{ 66 "union", 67 amfs_generic_match, 68 0, /* amfs_union_init */ 69 amfs_toplvl_mount, 70 amfs_toplvl_umount, 71 amfs_generic_lookup_child, 72 amfs_generic_mount_child, 73 amfs_generic_readdir, 74 0, /* amfs_union_readlink */ 75 amfs_union_mounted, 76 0, /* amfs_union_umounted */ 77 amfs_generic_find_srvr, 78 0, /* amfs_union_get_wchan */ 79 FS_MKMNT | FS_NOTIMEOUT | FS_BACKGROUND | FS_AMQINFO | FS_DIRECTORY, 80#ifdef HAVE_FS_AUTOFS 81 AUTOFS_UNION_FS_FLAGS, 82#endif /* HAVE_FS_AUTOFS */ 83}; 84 85 86/* 87 * Create a reference to a union'ed entry 88 * XXX: this function may not be used anywhere... 89 */ 90static int 91create_amfs_union_node(char *dir, opaque_t arg) 92{ 93 if (!STREQ(dir, "/defaults")) { 94 int error = 0; 95 am_node *am; 96 am = amfs_generic_lookup_child(arg, dir, &error, VLOOK_CREATE); 97 if (am && error < 0) 98 am = amfs_generic_mount_child(am, &error); 99 if (error > 0) { 100 errno = error; /* XXX */ 101 plog(XLOG_ERROR, "unionfs: could not mount %s: %m", dir); 102 } 103 return error; 104 } 105 return 0; 106} 107 108 109static void 110amfs_union_mounted(mntfs *mf) 111{ 112 int index; 113 am_node *mp; 114 115 amfs_mkcacheref(mf); 116 117 /* 118 * Having made the union mount point, 119 * populate all the entries... 120 */ 121 for (mp = get_first_exported_ap(&index); 122 mp; 123 mp = get_next_exported_ap(&index)) { 124 if (mp->am_mnt == mf) { 125 /* return value from create_amfs_union_node is ignored by mapc_keyiter */ 126 (void) mapc_keyiter((mnt_map *) mp->am_mnt->mf_private, 127 create_amfs_union_node, 128 mp); 129 break; 130 } 131 } 132} 133