1 /*
2  * volume_id - reads filesystem label and uuid
3  *
4  * Copyright (C) 2004 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_EXT
21 //config:	bool "Ext filesystem"
22 //config:	default y
23 //config:	depends on VOLUMEID
24 
25 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_EXT) += ext.o
26 
27 #include "volume_id_internal.h"
28 #include "bb_e2fs_defs.h"
29 
30 #define EXT_SUPERBLOCK_OFFSET			0x400
31 
volume_id_probe_ext(struct volume_id * id)32 int FAST_FUNC volume_id_probe_ext(struct volume_id *id /*,uint64_t off*/)
33 {
34 #define off ((uint64_t)0)
35 	struct ext2_super_block *es;
36 
37 	dbg("ext: probing at offset 0x%llx", (unsigned long long) off);
38 
39 	es = volume_id_get_buffer(id, off + EXT_SUPERBLOCK_OFFSET, 0x200);
40 	if (es == NULL)
41 		return -1;
42 
43 	if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
44 		dbg("ext: no magic found");
45 		return -1;
46 	}
47 
48 //	volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
49 //	volume_id_set_label_raw(id, es->volume_name, 16);
50 	volume_id_set_label_string(id, (void*)es->s_volume_name, 16);
51 	volume_id_set_uuid(id, es->s_uuid, UUID_DCE);
52 	dbg("ext: label '%s' uuid '%s'", id->label, id->uuid);
53 
54 #if ENABLE_FEATURE_BLKID_TYPE
55 	if ((es->s_feature_ro_compat & cpu_to_le32(EXT4_FEATURE_RO_COMPAT_HUGE_FILE | EXT4_FEATURE_RO_COMPAT_DIR_NLINK))
56 	 || (es->s_feature_incompat & cpu_to_le32(EXT4_FEATURE_INCOMPAT_EXTENTS | EXT4_FEATURE_INCOMPAT_64BIT))
57 	) {
58 		id->type = "ext4";
59 	}
60 	else if (es->s_feature_compat & cpu_to_le32(EXT3_FEATURE_COMPAT_HAS_JOURNAL))
61 		id->type = "ext3";
62 	else
63 		id->type = "ext2";
64 #endif
65 	return 0;
66 }
67