2 * mdadm - manage Linux "md" devices aka RAID arrays.
4 * Copyright (C) 2010 Neil Brown <neilb@suse.de>
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.
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.
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
22 * Email: <neil@brown.name>
27 * 'mbr' is a pseudo metadata type for devices which have a
28 * partition table in the Master Boot Record (mbr) also known
29 * as a dos partition table.
31 * Obviously arrays cannot be created or assembled for this type.
32 * It is used to allow a new bare device to have an partition table
33 * added so the member partitions can then be included in other
36 * The meaning operations are:
37 * examine_super, but not brief_examine_super or export_examine
45 static void free_mbr(struct supertype *st)
53 static void examine_mbr(struct supertype *st, char *homehost)
55 struct MBR *sb = st->sb;
58 printf(" MBR Magic : %04x\n", sb->magic);
59 for (i = 0; i < MBR_PARTITIONS; i++)
61 * Have to make every access through sb rather than using a
62 * pointer to the partition table (or an entry), since the
63 * entries are not properly aligned.
65 if (sb->parts[i].blocks_num)
66 printf("Partition[%d] : %12lu sectors at %12lu (type %02x)\n",
68 (unsigned long)__le32_to_cpu(sb->parts[i].blocks_num),
69 (unsigned long)__le32_to_cpu(sb->parts[i].first_sect_lba),
70 sb->parts[i].part_type);
74 #endif /*MDASSEMBLE */
76 static int load_super_mbr(struct supertype *st, int fd, char *devname)
82 * 2 record is meaningless
88 if (posix_memalign((void**)&super, 512, 512) != 0) {
89 pr_err("could not allocate superblock\n");
94 if (read(fd, super, sizeof(*super)) != sizeof(*super)) {
96 pr_err("Cannot read partition table on %s\n",
102 if (super->magic != MBR_SIGNATURE_MAGIC) {
104 pr_err("No partition table found on %s\n",
112 if (st->ss == NULL) {
114 st->minor_version = 0;
121 static int store_mbr(struct supertype *st, int fd)
123 struct MBR *old, *super;
125 if (posix_memalign((void**)&old, 512, 512) != 0) {
126 pr_err("could not allocate superblock\n");
131 if (read(fd, old, sizeof(*old)) != sizeof(*old)) {
137 memcpy(super->pad, old->pad, sizeof(super->pad));
140 if (write(fd, super, sizeof(*super)) != sizeof(*super))
143 ioctl(fd, BLKRRPART, 0);
147 static void getinfo_mbr(struct supertype *st, struct mdinfo *info, char *map)
149 struct MBR *sb = st->sb;
152 memset(&info->array, 0, sizeof(info->array));
153 memset(&info->disk, 0, sizeof(info->disk));
154 strcpy(info->text_version, "mbr");
155 strcpy(info->name, "mbr");
156 info->component_size = 0;
158 for (i = 0; i < MBR_PARTITIONS ; i++)
160 * Have to make every access through sb rather than using a
161 * pointer to the partition table (or an entry), since the
162 * entries are not properly aligned.
164 if (sb->parts[i].blocks_num) {
166 (unsigned long)__le32_to_cpu(sb->parts[i].blocks_num)
167 + (unsigned long)__le32_to_cpu(sb->parts[i].first_sect_lba);
168 if (last > info->component_size)
169 info->component_size = last;
174 static struct supertype *match_metadata_desc(char *arg)
176 struct supertype *st;
178 if (strcmp(arg, "mbr") != 0)
181 st = xmalloc(sizeof(*st));
184 st->minor_version = 0;
191 static int validate_geometry(struct supertype *st, int level,
192 int layout, int raiddisks,
193 int *chunk, unsigned long long size,
194 unsigned long long data_offset,
195 char *subdev, unsigned long long *freesize,
198 pr_err("mbr metadata cannot be used this way\n");
203 struct superswitch mbr = {
205 .examine_super = examine_mbr,
206 .validate_geometry = validate_geometry,
208 .match_metadata_desc = match_metadata_desc,
209 .load_super = load_super_mbr,
210 .store_super = store_mbr,
211 .getinfo_super = getinfo_mbr,
212 .free_super = free_mbr,