File: /usr/src/linux/fs/partitions/mac.c
1 /*
2 * fs/partitions/mac.c
3 *
4 * Code extracted from drivers/block/genhd.c
5 * Copyright (C) 1991-1998 Linus Torvalds
6 * Re-organised Feb 1998 Russell King
7 */
8
9 #include <linux/config.h>
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/system.h>
19
20 #include "check.h"
21 #include "mac.h"
22
23 #ifdef CONFIG_PPC
24 extern void note_bootable_part(kdev_t dev, int part, int goodness);
25 #endif
26
27 /*
28 * Code to understand MacOS partition tables.
29 */
30
31 static inline void mac_fix_string(char *stg, int len)
32 {
33 int i;
34
35 for (i = len - 1; i >= 0 && stg[i] == ' '; i--)
36 stg[i] = 0;
37 }
38
39 int mac_partition(struct gendisk *hd, kdev_t dev, unsigned long fsec, int first_part_minor)
40 {
41 struct buffer_head *bh;
42 int blk, blocks_in_map;
43 int dev_bsize, dev_pos, pos;
44 unsigned secsize;
45 #ifdef CONFIG_PPC
46 int found_root = 0;
47 int found_root_goodness = 0;
48 #endif
49 struct mac_partition *part;
50 struct mac_driver_desc *md;
51
52 dev_bsize = get_ptable_blocksize(dev);
53 dev_pos = 0;
54 /* Get 0th block and look at the first partition map entry. */
55 if ((bh = bread(dev, 0, dev_bsize)) == 0) {
56 printk("%s: error reading partition table\n",
57 kdevname(dev));
58 return -1;
59 }
60 md = (struct mac_driver_desc *) bh->b_data;
61 if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) {
62 brelse(bh);
63 return 0;
64 }
65 secsize = be16_to_cpu(md->block_size);
66 if (secsize >= dev_bsize) {
67 brelse(bh);
68 dev_pos = secsize;
69 if ((bh = bread(dev, secsize/dev_bsize, dev_bsize)) == 0) {
70 printk("%s: error reading Mac partition table\n",
71 kdevname(dev));
72 return -1;
73 }
74 }
75 part = (struct mac_partition *) (bh->b_data + secsize - dev_pos);
76 if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) {
77 brelse(bh);
78 return 0; /* not a MacOS disk */
79 }
80 printk(" [mac]");
81 blocks_in_map = be32_to_cpu(part->map_count);
82 for (blk = 1; blk <= blocks_in_map; ++blk) {
83 pos = blk * secsize;
84 if (pos >= dev_pos + dev_bsize) {
85 brelse(bh);
86 dev_pos = pos;
87 if ((bh = bread(dev, pos/dev_bsize, dev_bsize)) == 0) {
88 printk("%s: error reading partition table\n",
89 kdevname(dev));
90 return -1;
91 }
92 }
93 part = (struct mac_partition *) (bh->b_data + pos - dev_pos);
94 if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC)
95 break;
96 blocks_in_map = be32_to_cpu(part->map_count);
97 add_gd_partition(hd, first_part_minor,
98 fsec + be32_to_cpu(part->start_block) * (secsize/512),
99 be32_to_cpu(part->block_count) * (secsize/512));
100
101 #ifdef CONFIG_PPC
102 /*
103 * If this is the first bootable partition, tell the
104 * setup code, in case it wants to make this the root.
105 */
106 if (_machine == _MACH_Pmac) {
107 int goodness = 0;
108
109 mac_fix_string(part->processor, 16);
110 mac_fix_string(part->name, 32);
111 mac_fix_string(part->type, 32);
112
113 if ((be32_to_cpu(part->status) & MAC_STATUS_BOOTABLE)
114 && strcasecmp(part->processor, "powerpc") == 0)
115 goodness++;
116
117 if (strcasecmp(part->type, "Apple_UNIX_SVR2") == 0
118 || (strnicmp(part->type, "Linux", 5) == 0
119 && strcasecmp(part->type, "Linux_swap") != 0)) {
120 int i, l;
121
122 goodness++;
123 l = strlen(part->name);
124 if (strcmp(part->name, "/") == 0)
125 goodness++;
126 for (i = 0; i <= l - 4; ++i) {
127 if (strnicmp(part->name + i, "root",
128 4) == 0) {
129 goodness += 2;
130 break;
131 }
132 }
133 if (strnicmp(part->name, "swap", 4) == 0)
134 goodness--;
135 }
136
137 if (goodness > found_root_goodness) {
138 found_root = blk;
139 found_root_goodness = goodness;
140 }
141 }
142 #endif /* CONFIG_PPC */
143
144 ++first_part_minor;
145 }
146 #ifdef CONFIG_PPC
147 if (found_root_goodness)
148 note_bootable_part(dev, found_root, found_root_goodness);
149 #endif
150 brelse(bh);
151 printk("\n");
152 return 1;
153 }
154
155