2 * fs/partitions/atari.c
4 * Code extracted from drivers/block/genhd.c
6 * Copyright (C) 1991-1998 Linus Torvalds
7 * Re-organised Feb 1998 Russell King
11 #include <linux/genhd.h>
12 #include <linux/kernel.h>
13 #include <linux/major.h>
14 #include <linux/string.h>
15 #include <linux/blk.h>
16 #include <linux/ctype.h>
18 #include <asm/byteorder.h>
19 #include <asm/system.h>
24 /* ++guenther: this should be settable by the user ("make config")?.
28 /* check if a partition entry looks valid -- Atari format is assumed if at
29 least one of the primary entries is ok this way */
30 #define VALID_PARTITION(pi,hdsiz) \
32 isalnum((pi)->id[0]) && isalnum((pi)->id[1]) && isalnum((pi)->id[2]) && \
33 be32_to_cpu((pi)->st) <= (hdsiz) && \
34 be32_to_cpu((pi)->st) + be32_to_cpu((pi)->siz) <= (hdsiz))
36 int atari_partition (struct gendisk *hd, kdev_t dev,
37 unsigned long first_sector, int minor)
39 int m_lim = minor + hd->max_p;
40 struct buffer_head *bh;
41 struct rootsector *rs;
42 struct partition_info *pi;
46 int part_fmt = 0; /* 0:unknown, 1:AHDI, 2:ICD/Supra */
49 bh = bread (dev, 0, get_ptable_blocksize(dev));
51 if (warn_no_part) printk (" unable to read block 0 (partition table)\n");
55 /* Verify this is an Atari rootsector: */
56 rs = (struct rootsector *) bh->b_data;
57 hd_size = hd->part[minor - 1].nr_sects;
58 if (!VALID_PARTITION(&rs->part[0], hd_size) &&
59 !VALID_PARTITION(&rs->part[1], hd_size) &&
60 !VALID_PARTITION(&rs->part[2], hd_size) &&
61 !VALID_PARTITION(&rs->part[3], hd_size)) {
62 /* if there's no valid primary partition, assume that no Atari
63 format partition table (there's no reliable magic or the like
71 for (; pi < &rs->part[4] && minor < m_lim; minor++, pi++)
74 /* active partition */
76 if (memcmp (pi->id, "XGM", 3) == 0)
77 /* extension partition */
79 struct rootsector *xrs;
80 struct buffer_head *xbh;
87 partsect = extensect = be32_to_cpu(pi->st);
90 xbh = bread (dev, partsect / 2, get_ptable_blocksize(dev));
93 printk (" block %ld read failed\n", partsect);
98 xrs = (struct rootsector *) &xbh->b_data[512];
100 xrs = (struct rootsector *) &xbh->b_data[0];
102 /* ++roman: sanity check: bit 0 of flg field must be set */
103 if (!(xrs->part[0].flg & 1)) {
104 printk( "\nFirst sub-partition in extended partition is not valid!\n" );
108 add_gd_partition(hd, minor,
109 partsect + be32_to_cpu(xrs->part[0].st),
110 be32_to_cpu(xrs->part[0].siz));
112 if (!(xrs->part[1].flg & 1)) {
113 /* end of linked partition list */
117 if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
118 printk( "\nID of extended partition is not XGM!\n" );
123 partsect = be32_to_cpu(xrs->part[1].st) + extensect;
126 if (minor >= m_lim) {
127 printk( "\nMaximum number of partitions reached!\n" );
135 /* we don't care about other id's */
136 add_gd_partition (hd, minor, be32_to_cpu(pi->st),
137 be32_to_cpu(pi->siz));
142 if ( part_fmt!=1 ) /* no extended partitions -> test ICD-format */
144 pi = &rs->icdpart[0];
145 /* sanity check: no ICD format if first partition invalid */
146 if (memcmp (pi->id, "GEM", 3) == 0 ||
147 memcmp (pi->id, "BGM", 3) == 0 ||
148 memcmp (pi->id, "LNX", 3) == 0 ||
149 memcmp (pi->id, "SWP", 3) == 0 ||
150 memcmp (pi->id, "RAW", 3) == 0 )
153 for (; pi < &rs->icdpart[8] && minor < m_lim; minor++, pi++)
155 /* accept only GEM,BGM,RAW,LNX,SWP partitions */
157 (memcmp (pi->id, "GEM", 3) == 0 ||
158 memcmp (pi->id, "BGM", 3) == 0 ||
159 memcmp (pi->id, "LNX", 3) == 0 ||
160 memcmp (pi->id, "SWP", 3) == 0 ||
161 memcmp (pi->id, "RAW", 3) == 0) )
164 add_gd_partition (hd, minor, be32_to_cpu(pi->st),
165 be32_to_cpu(pi->siz));