xref: /freebsd/lib/libufs/type.c (revision 9768746b)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002 Juli Mallett.  All rights reserved.
5  *
6  * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
7  * FreeBSD project.  Redistribution and use in source and binary forms, with
8  * or without modification, are permitted provided that the following
9  * conditions are met:
10  *
11  * 1. Redistribution of source code must retain the above copyright notice,
12  *    this list of conditions and the following disclaimer.
13  * 2. Redistribution in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
21  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
25  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
26  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
27  * POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include <sys/param.h>
34 #include <sys/mount.h>
35 #include <sys/disklabel.h>
36 #include <sys/stat.h>
37 
38 #include <ufs/ufs/extattr.h>
39 #include <ufs/ufs/quota.h>
40 #include <ufs/ufs/ufsmount.h>
41 #include <ufs/ufs/dinode.h>
42 #include <ufs/ffs/fs.h>
43 
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <fstab.h>
47 #include <paths.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 
53 #include <libufs.h>
54 
55 /* Internally, track the 'name' value, it's ours. */
56 #define	MINE_NAME	0x01
57 /* Track if its fd points to a writable device. */
58 #define	MINE_WRITE	0x02
59 
60 int
61 ufs_disk_close(struct uufsd *disk)
62 {
63 	ERROR(disk, NULL);
64 	close(disk->d_fd);
65 	disk->d_fd = -1;
66 	if (disk->d_inoblock != NULL) {
67 		free(disk->d_inoblock);
68 		disk->d_inoblock = NULL;
69 	}
70 	if (disk->d_mine & MINE_NAME) {
71 		free((char *)(uintptr_t)disk->d_name);
72 		disk->d_name = NULL;
73 	}
74 	if (disk->d_si != NULL) {
75 		free(disk->d_si->si_csp);
76 		free(disk->d_si);
77 		disk->d_si = NULL;
78 	}
79 	return (0);
80 }
81 
82 int
83 ufs_disk_fillout(struct uufsd *disk, const char *name)
84 {
85 	if (ufs_disk_fillout_blank(disk, name) == -1) {
86 		return (-1);
87 	}
88 	if (sbread(disk) == -1) {
89 		ERROR(disk, "could not read superblock to fill out disk");
90 		ufs_disk_close(disk);
91 		return (-1);
92 	}
93 	return (0);
94 }
95 
96 int
97 ufs_disk_fillout_blank(struct uufsd *disk, const char *name)
98 {
99 	struct stat st;
100 	struct fstab *fs;
101 	struct statfs sfs;
102 	const char *oname;
103 	char dev[MAXPATHLEN];
104 	int fd, ret;
105 
106 	ERROR(disk, NULL);
107 
108 	oname = name;
109 again:	if ((ret = stat(name, &st)) < 0) {
110 		if (*name != '/') {
111 			snprintf(dev, sizeof(dev), "%s%s", _PATH_DEV, name);
112 			name = dev;
113 			goto again;
114 		}
115 		/*
116 		 * The given object doesn't exist, but don't panic just yet -
117 		 * it may be still mount point listed in /etc/fstab, but without
118 		 * existing corresponding directory.
119 		 */
120 		name = oname;
121 	}
122 	if (ret >= 0 && S_ISREG(st.st_mode)) {
123 		/* Possibly a disk image, give it a try.  */
124 		;
125 	} else if (ret >= 0 && S_ISCHR(st.st_mode)) {
126 		/* This is what we need, do nothing. */
127 		;
128 	} else if ((fs = getfsfile(name)) != NULL) {
129 		/*
130 		 * The given mount point is listed in /etc/fstab.
131 		 * It is possible that someone unmounted file system by hand
132 		 * and different file system is mounted on this mount point,
133 		 * but we still prefer /etc/fstab entry, because on the other
134 		 * hand, there could be /etc/fstab entry for this mount
135 		 * point, but file system is not mounted yet (eg. noauto) and
136 		 * statfs(2) will point us at different file system.
137 		 */
138 		name = fs->fs_spec;
139 	} else if (ret >= 0 && S_ISDIR(st.st_mode)) {
140 		/*
141 		 * The mount point is not listed in /etc/fstab, so it may be
142 		 * file system mounted by hand.
143 		 */
144 		if (statfs(name, &sfs) < 0) {
145 			ERROR(disk, "could not find special device");
146 			return (-1);
147 		}
148 		strlcpy(dev, sfs.f_mntfromname, sizeof(dev));
149 		name = dev;
150 	} else {
151 		ERROR(disk, "could not find special device");
152 		return (-1);
153 	}
154 	fd = open(name, O_RDONLY);
155 	if (fd == -1) {
156 		ERROR(disk, "could not open special device");
157 		return (-1);
158 	}
159 
160 	disk->d_bsize = 1;
161 	disk->d_ccg = 0;
162 	disk->d_fd = fd;
163 	disk->d_inoblock = NULL;
164 	disk->d_inomin = 0;
165 	disk->d_inomax = 0;
166 	disk->d_lcg = 0;
167 	disk->d_mine = 0;
168 	disk->d_ufs = 0;
169 	disk->d_error = NULL;
170 	disk->d_si = NULL;
171 	disk->d_sblockloc = UFS_STDSB;
172 	disk->d_lookupflags = 0;
173 
174 	if (oname != name) {
175 		name = strdup(name);
176 		if (name == NULL) {
177 			ERROR(disk, "could not allocate memory for disk name");
178 			return (-1);
179 		}
180 		disk->d_mine |= MINE_NAME;
181 	}
182 	disk->d_name = name;
183 
184 	return (0);
185 }
186 
187 int
188 ufs_disk_write(struct uufsd *disk)
189 {
190 	int fd;
191 
192 	ERROR(disk, NULL);
193 
194 	if (disk->d_mine & MINE_WRITE)
195 		return (0);
196 
197 	fd = open(disk->d_name, O_RDWR);
198 	if (fd < 0) {
199 		ERROR(disk, "failed to open disk for writing");
200 		return (-1);
201 	}
202 
203 	close(disk->d_fd);
204 	disk->d_fd = fd;
205 	disk->d_mine |= MINE_WRITE;
206 
207 	return (0);
208 }
209