1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * fs/partitions/mac.c
4 *
5 * Code extracted from drivers/block/genhd.c
6 * Copyright (C) 1991-1998 Linus Torvalds
7 * Re-organised Feb 1998 Russell King
8 */
9
10 #include <linux/ctype.h>
11 #include "check.h"
12 #include "mac.h"
13
14 #ifdef CONFIG_PPC_PMAC
15 #include <asm/machdep.h>
16 extern void note_bootable_part(dev_t dev, int part, int goodness);
17 #endif
18
19 /*
20 * Code to understand MacOS partition tables.
21 */
22
mac_fix_string(char * stg,int len)23 static inline void mac_fix_string(char *stg, int len)
24 {
25 int i;
26
27 for (i = len - 1; i >= 0 && stg[i] == ' '; i--)
28 stg[i] = 0;
29 }
30
mac_partition(struct parsed_partitions * state)31 int mac_partition(struct parsed_partitions *state)
32 {
33 Sector sect;
34 unsigned char *data;
35 int slot, blocks_in_map;
36 unsigned secsize, datasize, partoffset;
37 #ifdef CONFIG_PPC_PMAC
38 int found_root = 0;
39 int found_root_goodness = 0;
40 #endif
41 struct mac_partition *part;
42 struct mac_driver_desc *md;
43
44 /* Get 0th block and look at the first partition map entry. */
45 md = read_part_sector(state, 0, §);
46 if (!md)
47 return -1;
48 if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) {
49 put_dev_sector(sect);
50 return 0;
51 }
52 secsize = be16_to_cpu(md->block_size);
53 put_dev_sector(sect);
54 datasize = round_down(secsize, 512);
55 data = read_part_sector(state, datasize / 512, §);
56 if (!data)
57 return -1;
58 partoffset = secsize % 512;
59 if (partoffset + sizeof(*part) > datasize)
60 return -1;
61 part = (struct mac_partition *) (data + partoffset);
62 if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) {
63 put_dev_sector(sect);
64 return 0; /* not a MacOS disk */
65 }
66 blocks_in_map = be32_to_cpu(part->map_count);
67 if (blocks_in_map < 0 || blocks_in_map >= DISK_MAX_PARTS) {
68 put_dev_sector(sect);
69 return 0;
70 }
71
72 if (blocks_in_map >= state->limit)
73 blocks_in_map = state->limit - 1;
74
75 strlcat(state->pp_buf, " [mac]", PAGE_SIZE);
76 for (slot = 1; slot <= blocks_in_map; ++slot) {
77 int pos = slot * secsize;
78 put_dev_sector(sect);
79 data = read_part_sector(state, pos/512, §);
80 if (!data)
81 return -1;
82 part = (struct mac_partition *) (data + pos%512);
83 if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC)
84 break;
85 put_partition(state, slot,
86 be32_to_cpu(part->start_block) * (secsize/512),
87 be32_to_cpu(part->block_count) * (secsize/512));
88
89 if (!strncasecmp(part->type, "Linux_RAID", 10))
90 state->parts[slot].flags = ADDPART_FLAG_RAID;
91 #ifdef CONFIG_PPC_PMAC
92 /*
93 * If this is the first bootable partition, tell the
94 * setup code, in case it wants to make this the root.
95 */
96 if (machine_is(powermac)) {
97 int goodness = 0;
98
99 mac_fix_string(part->processor, 16);
100 mac_fix_string(part->name, 32);
101 mac_fix_string(part->type, 32);
102
103 if ((be32_to_cpu(part->status) & MAC_STATUS_BOOTABLE)
104 && strcasecmp(part->processor, "powerpc") == 0)
105 goodness++;
106
107 if (strcasecmp(part->type, "Apple_UNIX_SVR2") == 0
108 || (strncasecmp(part->type, "Linux", 5) == 0
109 && strcasecmp(part->type, "Linux_swap") != 0)) {
110 int i, l;
111
112 goodness++;
113 l = strlen(part->name);
114 if (strcmp(part->name, "/") == 0)
115 goodness++;
116 for (i = 0; i <= l - 4; ++i) {
117 if (strncasecmp(part->name + i, "root",
118 4) == 0) {
119 goodness += 2;
120 break;
121 }
122 }
123 if (strncasecmp(part->name, "swap", 4) == 0)
124 goodness--;
125 }
126
127 if (goodness > found_root_goodness) {
128 found_root = slot;
129 found_root_goodness = goodness;
130 }
131 }
132 #endif /* CONFIG_PPC_PMAC */
133 }
134 #ifdef CONFIG_PPC_PMAC
135 if (found_root_goodness)
136 note_bootable_part(state->disk->part0->bd_dev, found_root,
137 found_root_goodness);
138 #endif
139
140 put_dev_sector(sect);
141 strlcat(state->pp_buf, "\n", PAGE_SIZE);
142 return 1;
143 }
144