xref: /freebsd/lib/libufs/sblock.c (revision b52b9d56d4e96089873a75f9e29062eec19fabba)
1 /*
2  * Copyright (c) 2002 Juli Mallett.  All rights reserved.
3  *
4  * This software was written by Juli Mallett <jmallett@FreeBSD.org> for the
5  * FreeBSD project.  Redistribution and use in source and binary forms, with
6  * or without modification, are permitted provided that the following
7  * conditions are met:
8  *
9  * 1. Redistribution of source code must retain the above copyright notice,
10  *    this list of conditions and the following disclaimer.
11  * 2. Redistribution in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
19  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
20  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
23  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
24  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
25  * POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/mount.h>
33 #include <sys/disklabel.h>
34 #include <sys/stat.h>
35 
36 #include <ufs/ufs/ufsmount.h>
37 #include <ufs/ufs/dinode.h>
38 #include <ufs/ffs/fs.h>
39 
40 #include <errno.h>
41 #include <fcntl.h>
42 #include <stdio.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #include <libufs.h>
47 
48 static int superblocks[] = SBLOCKSEARCH;
49 
50 int
51 sbread(struct uufsd *disk)
52 {
53 	struct fs *fs;
54 	int sb, superblock;
55 
56 	DEBUG(NULL);
57 
58 	fs = &disk->d_fs;
59 	superblock = superblocks[0];
60 
61 	for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
62 		if (bread(disk, superblock, disk->d_sb, SBLOCKSIZE) == -1) {
63 			DEBUG(NULL);
64 			return -1;
65 		}
66 		if (fs->fs_magic == FS_UFS1_MAGIC)
67 			disk->d_ufs = 1;
68 		if ((fs->fs_magic == FS_UFS2_MAGIC) &&
69 		    (fs->fs_sblockloc == numfrags(fs, superblock)))
70 			disk->d_ufs = 2;
71 		if ((fs->fs_bsize <= MAXBSIZE) &&
72 		    (fs->fs_bsize >= sizeof(*fs))) {
73 			if (disk->d_ufs)
74 				break;
75 		}
76 		disk->d_ufs = 0;
77 	}
78 	if (superblock == -1 || disk->d_ufs == 0) {
79 		/*
80 		 * Other error cases will result in errno being set, here we
81 		 * must set it to indicate no superblock could be found with
82 		 * which to associate this disk/filesystem.
83 		 */
84 		DEBUG("no superblock found");
85 		errno = ENOENT;
86 		return -1;
87 	}
88 	disk->d_bsize = fs->fs_fsize / fsbtodb(fs, 1);
89 	disk->d_sblock = superblock / disk->d_bsize;
90 	return 0;
91 }
92 
93 int
94 sbwrite(struct uufsd *disk, int all)
95 {
96 	struct fs *fs;
97 	int i, rofd;
98 
99 	DEBUG(NULL);
100 
101 	fs = &disk->d_fs;
102 
103 	rofd = disk->d_fd;
104 	disk->d_fd = open(disk->d_name, O_WRONLY);
105 	if (disk->d_fd < 0) {
106 		DEBUG("open");
107 		return -1;
108 	}
109 	if (bwrite(disk, disk->d_sblock, fs, SBLOCKSIZE) == -1) {
110 		DEBUG(NULL);
111 		return -1;
112 	}
113 	if (all) {
114 		for (i = 0; i < fs->fs_ncg; i++)
115 			if (bwrite(disk, fsbtodb(fs, cgsblock(fs, i)),
116 			    fs, SBLOCKSIZE) == -1) {
117 				DEBUG(NULL);
118 				return -1;
119 			}
120 	}
121 	close(disk->d_fd);
122 	disk->d_fd = rofd;
123 	return 0;
124 }
125