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_LINUXSWAP
21 //config: bool "linux swap filesystem"
22 //config: default y
23 //config: depends on VOLUMEID
24
25 //kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_LINUXSWAP) += linux_swap.o
26
27 #include "volume_id_internal.h"
28
29 struct swap_header_v1_2 {
30 uint8_t bootbits[1024];
31 uint32_t version;
32 uint32_t last_page;
33 uint32_t nr_badpages;
34 uint8_t uuid[16];
35 uint8_t volume_name[16];
36 } PACKED;
37
38 #define LARGEST_PAGESIZE 0x4000
39
volume_id_probe_linux_swap(struct volume_id * id)40 int FAST_FUNC volume_id_probe_linux_swap(struct volume_id *id /*,uint64_t off*/)
41 {
42 #define off ((uint64_t)0)
43 struct swap_header_v1_2 *sw;
44 const uint8_t *buf;
45 unsigned page;
46
47 dbg("probing at offset 0x%llx", (unsigned long long) off);
48
49 /* the swap signature is at the end of the PAGE_SIZE */
50 for (page = 0x1000; page <= LARGEST_PAGESIZE; page <<= 1) {
51 buf = volume_id_get_buffer(id, off + page-10, 10);
52 if (buf == NULL)
53 return -1;
54
55 if (memcmp(buf, "SWAP-SPACE", 10) == 0) {
56 // id->type_version[0] = '1';
57 // id->type_version[1] = '\0';
58 goto found;
59 }
60
61 if (memcmp(buf, "SWAPSPACE2", 10) == 0
62 || memcmp(buf, "S1SUSPEND", 9) == 0
63 || memcmp(buf, "S2SUSPEND", 9) == 0
64 || memcmp(buf, "ULSUSPEND", 9) == 0
65 ) {
66 sw = volume_id_get_buffer(id, off, sizeof(struct swap_header_v1_2));
67 if (sw == NULL)
68 return -1;
69 // id->type_version[0] = '2';
70 // id->type_version[1] = '\0';
71 // volume_id_set_label_raw(id, sw->volume_name, 16);
72 volume_id_set_label_string(id, sw->volume_name, 16);
73 volume_id_set_uuid(id, sw->uuid, UUID_DCE);
74 goto found;
75 }
76 }
77 return -1;
78
79 found:
80 // volume_id_set_usage(id, VOLUME_ID_OTHER);
81 IF_FEATURE_BLKID_TYPE(id->type = "swap";)
82
83 return 0;
84 }
85