1/* $NetBSD: umount_default.c,v 1.1.1.3 2015/01/17 16:34:16 christos Exp $ */ 2 3/* 4 * Copyright (c) 1997-2014 Erez Zadok 5 * Copyright (c) 1990 Jan-Simon Pendry 6 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine 7 * Copyright (c) 1990 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. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * 38 * File: am-utils/conf/umount/umount_default.c 39 * 40 */ 41 42/* 43 * Default method of unmounting filesystems. 44 */ 45 46#ifdef HAVE_CONFIG_H 47# include <config.h> 48#endif /* HAVE_CONFIG_H */ 49#include <am_defs.h> 50#include <amu.h> 51 52 53int 54umount_fs(char *mntdir, const char *mnttabname, u_int unmount_flags) 55{ 56 mntlist *mlist, *mp, *mp_save = NULL; 57 int error = 0; 58 59 mp = mlist = read_mtab(mntdir, mnttabname); 60 61 /* 62 * Search the mount table looking for 63 * the correct (ie last) matching entry 64 */ 65 while (mp) { 66 if (STREQ(mp->mnt->mnt_dir, mntdir)) 67 mp_save = mp; 68 mp = mp->mnext; 69 } 70 71 if (mp_save) { 72 dlog("Trying unmount(%s)", mp_save->mnt->mnt_dir); 73 74#ifdef MOUNT_TABLE_ON_FILE 75 /* 76 * This unmount may hang leaving this process with an exclusive lock on 77 * /etc/mtab. Therefore it is necessary to unlock mtab, do the unmount, 78 * then lock mtab (again) and reread it and finally update it. 79 */ 80 unlock_mntlist(); 81#endif /* MOUNT_TABLE_ON_FILE */ 82 83#ifdef NEED_AUTOFS_SPACE_HACK 84 if (unmount_flags & AMU_UMOUNT_AUTOFS) { 85 char *mnt_dir_save = mp_save->mnt->mnt_dir; 86 mp_save->mnt->mnt_dir = autofs_strdup_space_hack(mnt_dir_save); 87 error = UNMOUNT_TRAP(mp_save->mnt); 88 XFREE(mp_save->mnt->mnt_dir); 89 mp_save->mnt->mnt_dir = mnt_dir_save; 90 } else 91#endif /* NEED_AUTOFS_SPACE_HACK */ 92 error = UNMOUNT_TRAP(mp_save->mnt); 93 if (error < 0) { 94 switch ((error = errno)) { 95 case EINVAL: 96 case ENOTBLK: 97 plog(XLOG_WARNING, "unmount: %s is not mounted", mp_save->mnt->mnt_dir); 98 error = 0; /* Not really an error */ 99 break; 100 101 case ENOENT: 102 /* 103 * This could happen if the kernel insists on following symlinks 104 * when we try to unmount a direct mountpoint. We need to propagate 105 * the error up so that the top layers know it failed and don't 106 * try to rmdir() the mountpoint or other silly things. 107 */ 108 plog(XLOG_ERROR, "mount point %s: %m", mp_save->mnt->mnt_dir); 109 break; 110 111#if defined(MNT2_GEN_OPT_FORCE) && defined(HAVE_UMOUNT2) 112 case EBUSY: 113 case EIO: 114 case ESTALE: 115 /* caller determines if forced unmounts should be used */ 116 if (unmount_flags & AMU_UMOUNT_FORCE) { 117 error = umount2_fs(mntdir, unmount_flags); 118 if (error < 0) 119 error = errno; 120 else 121 break; /* all is OK */ 122 } 123 /* fallthrough */ 124#endif /* MNT2_GEN_OPT_FORCE && HAVE_UMOUNT2 */ 125 default: 126 dlog("%s: unmount: %m", mp_save->mnt->mnt_dir); 127 break; 128 } 129 } 130 dlog("Finished unmount(%s)", mp_save->mnt->mnt_dir); 131 132 if (!error) { 133#ifdef MOUNT_TABLE_ON_FILE 134 free_mntlist(mlist); 135 mp = mlist = read_mtab(mntdir, mnttabname); 136 137 /* 138 * Search the mount table looking for 139 * the correct (ie last) matching entry 140 */ 141 mp_save = NULL; 142 while (mp) { 143 if (STREQ(mp->mnt->mnt_dir, mntdir)) 144 mp_save = mp; 145 mp = mp->mnext; 146 } 147 148 if (mp_save) { 149 mnt_free(mp_save->mnt); 150 mp_save->mnt = NULL; 151 rewrite_mtab(mlist, mnttabname); 152 } 153#endif /* MOUNT_TABLE_ON_FILE */ 154 } 155 156 } else { 157 158 plog(XLOG_ERROR, "Couldn't find how to unmount %s", mntdir); 159 /* 160 * Assume it is already unmounted 161 */ 162 error = 0; 163 } /* end of "if (mp_save)" statement */ 164 165 free_mntlist(mlist); 166 167 return error; 168} 169 170 171#if defined(MNT2_GEN_OPT_FORCE) && defined(HAVE_UMOUNT2) 172/* force unmount, no questions asked, without touching mnttab file */ 173int 174umount2_fs(const char *mntdir, u_int unmount_flags) 175{ 176 int error = 0; 177 178 if (unmount_flags & AMU_UMOUNT_FORCE) { 179 plog(XLOG_INFO, "umount2_fs: trying unmount/forced on %s", mntdir); 180 error = umount2(mntdir, MNT2_GEN_OPT_FORCE); /* Solaris */ 181 if (error < 0 && (errno == EINVAL || errno == ENOENT)) 182 error = 0; /* ignore EINVAL/ENOENT */ 183 if (error < 0) 184 plog(XLOG_WARNING, "%s: unmount/force: %m", mntdir); 185 else 186 dlog("%s: unmount/force: OK", mntdir); 187 } 188 return error; 189} 190#endif /* MNT2_GEN_OPT_FORCE && HAVE_UMOUNT2 */ 191