xref: /freebsd/sys/geom/label/g_label_ufs.c (revision 9a41df2a0e6408e9b329bbd8b9e37c2b44461a1b)
1 /*-
2  * Copyright (c) 2002, 2003 Gordon Tetlow
3  * Copyright (c) 2006 Pawel Jakub Dawidek <pjd@FreeBSD.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions 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 AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 
36 #include <ufs/ufs/dinode.h>
37 #include <ufs/ffs/fs.h>
38 
39 #include <geom/geom.h>
40 #include <geom/label/g_label.h>
41 
42 #define G_LABEL_UFS_VOLUME_DIR	"ufs"
43 #define G_LABEL_UFS_ID_DIR	"ufsid"
44 
45 #define	G_LABEL_UFS_VOLUME	0
46 #define	G_LABEL_UFS_ID		1
47 
48 static const int superblocks[] = SBLOCKSEARCH;
49 
50 static void
51 g_label_ufs_taste_common(struct g_consumer *cp, char *label, size_t size, int what)
52 {
53 	struct g_provider *pp;
54 	int sb, superblock;
55 	struct fs *fs;
56 
57 	g_topology_assert_not();
58 	pp = cp->provider;
59 	label[0] = '\0';
60 
61 	if (SBLOCKSIZE % cp->provider->sectorsize != 0)
62 		return;
63 
64 	/*
65 	 * Walk through the standard places that superblocks hide and look
66 	 * for UFS magic. If we find magic, then check that the size in the
67 	 * superblock corresponds to the size of the underlying provider.
68 	 * Finally, look for a volume label and create an appropriate
69 	 * provider based on that.
70 	 */
71 	for (sb = 0; (superblock = superblocks[sb]) != -1; sb++) {
72 		/*
73 		 * Take care not to issue an invalid I/O request. The offset of
74 		 * the superblock candidate must be multiples of the provider's
75 		 * sector size, otherwise an FFS can't exist on the provider
76 		 * anyway.
77 		 */
78 		if (superblock % cp->provider->sectorsize != 0)
79 			continue;
80 
81 		fs = (struct fs *)g_read_data(cp, superblock, SBLOCKSIZE, NULL);
82 		if (fs == NULL)
83 			continue;
84 		/* Check for magic. We also need to check if file system size is equal
85 		 * to providers size, because sysinstall(8) used to bogusly put first
86 		 * partition at offset 0 instead of 16, and glabel/ufs would find file
87 		 * system on slice instead of partition.
88 		 */
89 		if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_fsize > 0 &&
90 		    pp->mediasize / fs->fs_fsize == fs->fs_old_size) {
91 		    	/* Valid UFS1. */
92 		} else if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_fsize > 0 &&
93 		    pp->mediasize / fs->fs_fsize == fs->fs_size) {
94 		    	/* Valid UFS2. */
95 		} else {
96 			g_free(fs);
97 			continue;
98 		}
99 		if (fs->fs_sblockloc != superblock || fs->fs_ncg < 1 ||
100 		    fs->fs_bsize < MINBSIZE ||
101 		    fs->fs_bsize < sizeof(struct fs)) {
102 			g_free(fs);
103 			continue;
104 		}
105 		G_LABEL_DEBUG(1, "%s file system detected on %s.",
106 		    fs->fs_magic == FS_UFS1_MAGIC ? "UFS1" : "UFS2", pp->name);
107 		switch (what) {
108 		case G_LABEL_UFS_VOLUME:
109 			/* Check for volume label */
110 			if (fs->fs_volname[0] == '\0') {
111 				g_free(fs);
112 				continue;
113 			}
114 			strlcpy(label, fs->fs_volname, size);
115 			break;
116 		case G_LABEL_UFS_ID:
117 			if (fs->fs_id[0] == 0 && fs->fs_id[1] == 0) {
118 				g_free(fs);
119 				continue;
120 			}
121 			snprintf(label, size, "%08x%08x", fs->fs_id[0],
122 			    fs->fs_id[1]);
123 			break;
124 		}
125 		g_free(fs);
126 		break;
127 	}
128 }
129 
130 static void
131 g_label_ufs_volume_taste(struct g_consumer *cp, char *label, size_t size)
132 {
133 
134 	g_label_ufs_taste_common(cp, label, size, G_LABEL_UFS_VOLUME);
135 }
136 
137 static void
138 g_label_ufs_id_taste(struct g_consumer *cp, char *label, size_t size)
139 {
140 
141 	g_label_ufs_taste_common(cp, label, size, G_LABEL_UFS_ID);
142 }
143 
144 struct g_label_desc g_label_ufs_volume = {
145 	.ld_taste = g_label_ufs_volume_taste,
146 	.ld_dir = G_LABEL_UFS_VOLUME_DIR,
147 	.ld_enabled = 1
148 };
149 
150 struct g_label_desc g_label_ufs_id = {
151 	.ld_taste = g_label_ufs_id_taste,
152 	.ld_dir = G_LABEL_UFS_ID_DIR,
153 	.ld_enabled = 1
154 };
155 
156 G_LABEL_INIT(ufsid, g_label_ufs_id, "Create device nodes for UFS file system IDs");
157 G_LABEL_INIT(ufs, g_label_ufs_volume, "Create device nodes for UFS volume names");
158