mdctl-v0.2
[thirdparty/mdadm.git] / util.c
CommitLineData
64c4757e
NB
1/*
2 * mdctl - manage Linux "md" devices aka RAID arrays.
3 *
4 * Copyright (C) 2001 Neil Brown <neilb@cse.unsw.edu.au>
5 *
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 * Author: Neil Brown
22 * Email: <neilb@cse.unsw.edu.au>
23 * Paper: Neil Brown
24 * School of Computer Science and Engineering
25 * The University of New South Wales
26 * Sydney, 2052
27 * Australia
28 */
29
30#include "mdctl.h"
31#include "md_p.h"
32#include <sys/utsname.h>
33
34/*
35 * Parse a 128 bit uuid in 4 integers
36 * format is 32 hexx nibbles with options :.<space> separator
37 * If not exactly 32 hex digits are found, return 0
38 * else return 1
39 */
40int parse_uuid(char *str, int uuid[4])
41{
42 int hit = 0; /* number of Hex digIT */
43 int i;
44 char c;
45 for (i=0; i<4; i++) uuid[i]=0;
46
47 while ((c= *str++)) {
48 int n;
49 if (c>='0' && c<='9')
50 n = c-'0';
51 else if (c>='a' && c <= 'f')
52 n = 10 + c - 'a';
53 else if (c>='A' && c <= 'F')
54 n = 10 + c - 'A';
55 else if (strchr(":. -", c))
56 continue;
57 else return 0;
58
59 uuid[hit/4] <<= 4;
60 uuid[hit/4] += n;
61 hit++;
62 }
63 if (hit == 32)
64 return 1;
65 return 0;
66
67}
68
69
70/*
71 * Get the md version number.
72 * We use the RAID_VERSION ioctl if it is supported
73 * If not, but we have a block device with major '9', we assume
74 * 0.36.0
75 *
76 * Return version number as 24 but number - assume version parts
77 * always < 255
78 */
79
80int md_get_version(int fd)
81{
82 struct stat stb;
83 mdu_version_t vers;
84
85 if (fstat(fd, &stb)<0)
86 return -1;
87 if ((S_IFMT&stb.st_mode) != S_IFBLK)
88 return -1;
89
90 if (ioctl(fd, RAID_VERSION, &vers) == 0)
91 return (vers.major<<16) | (vers.minor<<8) | vers.patchlevel;
92
93 if (MAJOR(stb.st_rdev) == MD_MAJOR)
94 return (36<<8);
95 return -1;
96}
97
98
99int get_linux_version()
100{
101 struct utsname name;
102 int a,b,c;
103 if (uname(&name) <0)
104 return -1;
105
106 if (sscanf(name.release, "%d.%d.%d", &a,&b,&c)!= 3)
107 return -1;
108 return (a<<16)+(b<<8)+c;
109}
110
111int enough(int level, int raid_disks, int avail_disks)
112{
113 switch (level) {
114 case -1:
115 case 0:
116 return avail_disks == raid_disks;
117 case 1:
118 return avail_disks >= 1;
119 case 4:
120 case 5:
121 return avail_disks >= raid_disks-1;
122 default:
123 return 0;
124 }
125}
126
127int same_uuid(int a[4], int b[4])
128{
129 if (a[0]==b[0] &&
130 a[1]==b[1] &&
131 a[2]==b[2] &&
132 a[3]==b[3])
133 return 1;
134 return 0;
135}
136
137void uuid_from_super(int uuid[4], mdp_super_t *super)
138{
139 uuid[0] = super->set_uuid0;
140 if (super->minor_version >= 90) {
141 uuid[1] = super->set_uuid1;
142 uuid[2] = super->set_uuid2;
143 uuid[3] = super->set_uuid3;
144 } else {
145 uuid[1] = 0;
146 uuid[2] = 0;
147 uuid[3] = 0;
148 }
149}
150
151int compare_super(mdp_super_t *first, mdp_super_t *second)
152{
153 /*
154 * return:
155 * 0 same, or first was empty, and second was copied
156 * 1 second had wrong number
157 * 2 wrong uuid
158 * 3 wrong other info
159 */
160 int uuid1[4], uuid2[4];
161 if (second->md_magic != MD_SB_MAGIC)
162 return 1;
163 if (first-> md_magic != MD_SB_MAGIC) {
164 memcpy(first, second, sizeof(*first));
165 return 0;
166 }
167
168 uuid_from_super(uuid1, first);
169 uuid_from_super(uuid2, second);
170 if (!same_uuid(uuid1, uuid2))
171 return 2;
172 if (first->major_version != second->major_version ||
173 first->minor_version != second->minor_version ||
174 first->patch_version != second->patch_version ||
175 first->gvalid_words != second->gvalid_words ||
176 first->ctime != second->ctime ||
177 first->level != second->level ||
178 first->size != second->size ||
179 first->raid_disks != second->raid_disks )
180 return 3;
181
182 return 0;
183}
184
185int load_super(int fd, mdp_super_t *super)
186{
187 /* try to read in the superblock
188 *
189 * return
190 * 0 - success
191 * 1 - no block size
192 * 2 - too small
193 * 3 - no seek
194 * 4 - no read
195 * 5 - no magic
196 * 6 - wrong major version
197 */
198 long size;
199 long long offset;
200
201 if (ioctl(fd, BLKGETSIZE, &size))
202 return 1;
203
204 if (size < MD_RESERVED_SECTORS*2)
205 return 2;
206
207 offset = MD_NEW_SIZE_SECTORS(size);
208
209 offset *= 512;
210
211 if (lseek64(fd, offset, 0)< 0LL)
212 return 3;
213
214 if (read(fd, &super, sizeof(super)) != sizeof(super))
215 return 4;
216
217 if (super->md_magic != MD_SB_MAGIC)
218 return 5;
219
220 if (super->major_version != 0)
221 return 6;
222 return 0;
223}
224