2 * Copyright (c) 2014 Juniper Networks, Inc.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/types.h>
31 #include <sys/diskmbr.h>
32 #include <sys/endian.h>
33 #include <sys/errno.h>
43 #define DOSPTYP_FAT32 0x0b
46 static struct mkimg_alias ebr_aliases[] = {
47 { ALIAS_FAT32, ALIAS_INT2TYPE(DOSPTYP_FAT32) },
48 { ALIAS_FREEBSD, ALIAS_INT2TYPE(DOSPTYP_386BSD) },
53 ebr_metadata(u_int where, lba_t blk)
56 blk += (where == SCHEME_META_PART_BEFORE) ? 1 : 0;
57 return (round_track(blk));
61 ebr_chs(u_char *cylp, u_char *hdp, u_char *secp, lba_t lba)
65 mkimg_chs(lba, 1023, &cyl, &hd, &sec);
68 *secp = (sec & 0x3f) | ((cyl >> 2) & 0xc0);
72 ebr_write(lba_t imgsz __unused, void *bootcode __unused)
75 struct dos_partition *dp;
76 struct part *part, *next;
83 memset(ebr, 0, secsz);
84 le16enc(ebr + DOSMAGICOFFSET, DOSMAGIC);
87 STAILQ_FOREACH_SAFE(part, &partlist, link, next) {
88 block = part->block - nsecs;
89 size = round_track(part->size);
90 dp = (void *)(ebr + DOSPARTOFF);
91 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect, nsecs);
92 dp->dp_typ = ALIAS_TYPE2INT(part->type);
93 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
94 part->block + size - 1);
95 le32enc(&dp->dp_start, nsecs);
96 le32enc(&dp->dp_size, size);
100 size = round_track(next->size);
102 ebr_chs(&dp->dp_scyl, &dp->dp_shd, &dp->dp_ssect,
103 next->block - nsecs);
104 dp->dp_typ = DOSPTYP_EXT;
105 ebr_chs(&dp->dp_ecyl, &dp->dp_ehd, &dp->dp_esect,
106 next->block + size - 1);
107 le32enc(&dp->dp_start, next->block - nsecs);
108 le32enc(&dp->dp_size, size + nsecs);
111 error = image_write(block, ebr, 1);
115 memset(ebr + DOSPARTOFF, 0, 2 * DOSPARTSIZE);
122 static struct mkimg_scheme ebr_scheme = {
124 .description = "Extended Boot Record",
125 .aliases = ebr_aliases,
126 .metadata = ebr_metadata,
132 SCHEME_DEFINE(ebr_scheme);