1/* 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. 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. 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. 22 * 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 33 * SUCH DAMAGE. 34 * 35 * 36 * File: am-utils/amd/amfs_union.c 37 * 38 */ 39 40/* 41 * Union automounter file system 42 */ 43 44#ifdef HAVE_CONFIG_H 45# include <config.h> 46#endif /* HAVE_CONFIG_H */ 47#include <am_defs.h> 48#include <amd.h> 49 50/**************************************************************************** 51 *** FORWARD DEFINITIONS *** 52 ****************************************************************************/ 53static int create_amfs_union_node(char *dir, opaque_t arg); 54static void amfs_union_mounted(mntfs *mf); 55 56 57/**************************************************************************** 58 *** OPS STRUCTURES *** 59 ****************************************************************************/ 60am_ops amfs_union_ops = 61{ 62 "union", 63 amfs_generic_match, 64 0, /* amfs_union_init */ 65 amfs_toplvl_mount, 66 amfs_toplvl_umount, 67 amfs_generic_lookup_child, 68 amfs_generic_mount_child, 69 amfs_generic_readdir, 70 0, /* amfs_union_readlink */ 71 amfs_union_mounted, 72 0, /* amfs_union_umounted */ 73 amfs_generic_find_srvr, 74 0, /* amfs_union_get_wchan */ 75 FS_MKMNT | FS_NOTIMEOUT | FS_BACKGROUND | FS_AMQINFO | FS_DIRECTORY, 76#ifdef HAVE_FS_AUTOFS 77 AUTOFS_UNION_FS_FLAGS, 78#endif /* HAVE_FS_AUTOFS */ 79}; 80 81 82/* 83 * Create a reference to a union'ed entry 84 * XXX: this function may not be used anywhere... 85 */ 86static int 87create_amfs_union_node(char *dir, opaque_t arg) 88{ 89 if (!STREQ(dir, "/defaults")) { 90 int error = 0; 91 am_node *am; 92 am = amfs_generic_lookup_child(arg, dir, &error, VLOOK_CREATE); 93 if (am && error < 0) 94 (void)amfs_generic_mount_child(am, &error); 95 if (error > 0) { 96 errno = error; /* XXX */ 97 plog(XLOG_ERROR, "unionfs: could not mount %s: %m", dir); 98 } 99 return error; 100 } 101 return 0; 102} 103 104 105static void 106amfs_union_mounted(mntfs *mf) 107{ 108 int index; 109 am_node *mp; 110 111 amfs_mkcacheref(mf); 112 113 /* 114 * Having made the union mount point, 115 * populate all the entries... 116 */ 117 for (mp = get_first_exported_ap(&index); 118 mp; 119 mp = get_next_exported_ap(&index)) { 120 if (mp->am_al->al_mnt == mf) { 121 /* return value from create_amfs_union_node is ignored by mapc_keyiter */ 122 (void) mapc_keyiter((mnt_map *) mp->am_al->al_mnt->mf_private, 123 create_amfs_union_node, 124 mp); 125 break; 126 } 127 } 128} 129