1 /*
2  * volume_id - reads filesystem label and uuid
3  *
4  * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
5  *
6  *	This library is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU Lesser General Public
8  *	License as published by the Free Software Foundation; either
9  *	version 2.1 of the License, or (at your option) any later version.
10  *
11  *	This library is distributed in the hope that it will be useful,
12  *	but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  *	Lesser General Public License for more details.
15  *
16  *	You should have received a copy of the GNU Lesser General Public
17  *	License along with this library; if not, write to the Free Software
18  *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19  */
20 //config:config FEATURE_VOLUMEID_MINIX
21 //config:	bool "minix filesystem"
22 //config:	default y
23 //config:	depends on VOLUMEID
24 
25 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_MINIX) += minix.o
26 
27 #include "volume_id_internal.h"
28 
29 struct minix_super_block {
30 	uint16_t	s_ninodes;
31 	uint16_t	s_nzones;
32 	uint16_t	s_imap_blocks;
33 	uint16_t	s_zmap_blocks;
34 	uint16_t	s_firstdatazone;
35 	uint16_t	s_log_zone_size;
36 	uint32_t	s_max_size;
37 	uint16_t	s_magic;
38 	uint16_t	s_state;
39 	uint32_t	s_zones;
40 } PACKED;
41 
42 /* V3 minix super-block data on disk */
43 struct minix3_super_block {
44 	uint32_t	s_ninodes;
45 	uint16_t	s_pad0;
46 	uint16_t	s_imap_blocks;
47 	uint16_t	s_zmap_blocks;
48 	uint16_t	s_firstdatazone;
49 	uint16_t	s_log_zone_size;
50 	uint16_t	s_pad1;
51 	uint32_t	s_max_size;
52 	uint32_t	s_zones;
53 	uint16_t	s_magic;
54 	uint16_t	s_pad2;
55 	uint16_t	s_blocksize;
56 	uint8_t		s_disk_version;
57 } PACKED;
58 
59 #define MINIX_SUPERBLOCK_OFFSET 0x400
60 
volume_id_probe_minix(struct volume_id * id)61 int FAST_FUNC volume_id_probe_minix(struct volume_id *id /*, uint64_t off*/)
62 {
63 #define off ((uint64_t)0)
64 	struct minix_super_block *ms;
65 	struct minix3_super_block *ms3;
66 
67 	dbg("probing at offset 0x%llx", (unsigned long long) off);
68 
69 	ms = volume_id_get_buffer(id, off + MINIX_SUPERBLOCK_OFFSET, 0x200);
70 	if (ms == NULL)
71 		return -1;
72 	if (ms->s_magic == cpu_to_le16(0x137F)) /* minix V1 fs, 14 char names */
73 		goto found;
74 	if (ms->s_magic == cpu_to_le16(0x138F)) /* minix V1 fs, 30 char names */
75 		goto found;
76 	if (ms->s_magic == cpu_to_le16(0x2468)) /* minix V2 fs, 14 char names */
77 		goto found;
78 	if (ms->s_magic == cpu_to_le16(0x2478)) /* minix V2 fs, 30 char names */
79 		goto found;
80 
81 	ms3 = (void*)ms;
82 	if (ms3->s_magic == cpu_to_le16(0x4d5a)) /* minix V3 fs, 60 char names */
83 		goto found;
84 
85 	return -1;
86 
87  found:
88 //	volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
89 	IF_FEATURE_BLKID_TYPE(id->type = "minix";)
90 	return 0;
91 }
92