1 /*
2 * fs/partitions/atari.c
3 *
4 * Code extracted from drivers/block/genhd.c
5 *
6 * Copyright (C) 1991-1998 Linus Torvalds
7 * Re-organised Feb 1998 Russell King
8 */
9
10 #include <linux/fs.h>
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>
17
18 #include <asm/byteorder.h>
19 #include <asm/system.h>
20
21 #include "check.h"
22 #include "atari.h"
23
24 /* ++guenther: this should be settable by the user ("make config")?.
25 */
26 #define ICD_PARTS
27
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) \
31 (((pi)->flg & 1) && \
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))
35
OK_id(char * s)36 static inline int OK_id(char *s)
37 {
38 return memcmp (s, "GEM", 3) == 0 || memcmp (s, "BGM", 3) == 0 ||
39 memcmp (s, "LNX", 3) == 0 || memcmp (s, "SWP", 3) == 0 ||
40 memcmp (s, "RAW", 3) == 0 ;
41 }
42
atari_partition(struct gendisk * hd,struct block_device * bdev,unsigned long first_sector,int minor)43 int atari_partition (struct gendisk *hd, struct block_device *bdev,
44 unsigned long first_sector, int minor)
45 {
46 int m_lim = minor + hd->max_p;
47 Sector sect;
48 struct rootsector *rs;
49 struct partition_info *pi;
50 u32 extensect;
51 u32 hd_size;
52 #ifdef ICD_PARTS
53 int part_fmt = 0; /* 0:unknown, 1:AHDI, 2:ICD/Supra */
54 #endif
55
56 rs = (struct rootsector *) read_dev_sector(bdev, 0, §);
57 if (!rs)
58 return -1;
59
60 /* Verify this is an Atari rootsector: */
61 hd_size = hd->part[minor - 1].nr_sects;
62 if (!VALID_PARTITION(&rs->part[0], hd_size) &&
63 !VALID_PARTITION(&rs->part[1], hd_size) &&
64 !VALID_PARTITION(&rs->part[2], hd_size) &&
65 !VALID_PARTITION(&rs->part[3], hd_size)) {
66 /*
67 * if there's no valid primary partition, assume that no Atari
68 * format partition table (there's no reliable magic or the like
69 * :-()
70 */
71 put_dev_sector(sect);
72 return 0;
73 }
74
75 pi = &rs->part[0];
76 printk (" AHDI");
77 for (; pi < &rs->part[4] && minor < m_lim; minor++, pi++) {
78 struct rootsector *xrs;
79 Sector sect2;
80 ulong partsect;
81
82 if ( !(pi->flg & 1) )
83 continue;
84 /* active partition */
85 if (memcmp (pi->id, "XGM", 3) != 0) {
86 /* we don't care about other id's */
87 add_gd_partition (hd, minor, be32_to_cpu(pi->st),
88 be32_to_cpu(pi->siz));
89 continue;
90 }
91 /* extension partition */
92 #ifdef ICD_PARTS
93 part_fmt = 1;
94 #endif
95 printk(" XGM<");
96 partsect = extensect = be32_to_cpu(pi->st);
97 while (1) {
98 xrs = (struct rootsector *)read_dev_sector(bdev, partsect, §2);
99 if (!xrs) {
100 printk (" block %ld read failed\n", partsect);
101 put_dev_sector(sect);
102 return 0;
103 }
104
105 /* ++roman: sanity check: bit 0 of flg field must be set */
106 if (!(xrs->part[0].flg & 1)) {
107 printk( "\nFirst sub-partition in extended partition is not valid!\n" );
108 put_dev_sector(sect2);
109 break;
110 }
111
112 add_gd_partition(hd, minor,
113 partsect + be32_to_cpu(xrs->part[0].st),
114 be32_to_cpu(xrs->part[0].siz));
115
116 if (!(xrs->part[1].flg & 1)) {
117 /* end of linked partition list */
118 put_dev_sector(sect2);
119 break;
120 }
121 if (memcmp( xrs->part[1].id, "XGM", 3 ) != 0) {
122 printk("\nID of extended partition is not XGM!\n");
123 put_dev_sector(sect2);
124 break;
125 }
126
127 partsect = be32_to_cpu(xrs->part[1].st) + extensect;
128 put_dev_sector(sect2);
129 minor++;
130 if (minor >= m_lim) {
131 printk( "\nMaximum number of partitions reached!\n" );
132 break;
133 }
134 }
135 printk(" >");
136 }
137 #ifdef ICD_PARTS
138 if ( part_fmt!=1 ) { /* no extended partitions -> test ICD-format */
139 pi = &rs->icdpart[0];
140 /* sanity check: no ICD format if first partition invalid */
141 if (OK_id(pi->id)) {
142 printk(" ICD<");
143 for (; pi < &rs->icdpart[8] && minor < m_lim; minor++, pi++) {
144 /* accept only GEM,BGM,RAW,LNX,SWP partitions */
145 if (!((pi->flg & 1) && OK_id(pi->id)))
146 continue;
147 part_fmt = 2;
148 add_gd_partition (hd, minor,
149 be32_to_cpu(pi->st),
150 be32_to_cpu(pi->siz));
151 }
152 printk(" >");
153 }
154 }
155 #endif
156 put_dev_sector(sect);
157
158 printk ("\n");
159
160 return 1;
161 }
162
163