xref: /openbmc/linux/block/partitions/mac.c (revision bc5aa3a0)
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/ctype.h>
10 #include "check.h"
11 #include "mac.h"
12 
13 #ifdef CONFIG_PPC_PMAC
14 #include <asm/machdep.h>
15 extern void note_bootable_part(dev_t dev, int part, int goodness);
16 #endif
17 
18 /*
19  * Code to understand MacOS partition tables.
20  */
21 
22 static inline void mac_fix_string(char *stg, int len)
23 {
24 	int i;
25 
26 	for (i = len - 1; i >= 0 && stg[i] == ' '; i--)
27 		stg[i] = 0;
28 }
29 
30 int mac_partition(struct parsed_partitions *state)
31 {
32 	Sector sect;
33 	unsigned char *data;
34 	int slot, blocks_in_map;
35 	unsigned secsize, datasize, partoffset;
36 #ifdef CONFIG_PPC_PMAC
37 	int found_root = 0;
38 	int found_root_goodness = 0;
39 #endif
40 	struct mac_partition *part;
41 	struct mac_driver_desc *md;
42 
43 	/* Get 0th block and look at the first partition map entry. */
44 	md = read_part_sector(state, 0, &sect);
45 	if (!md)
46 		return -1;
47 	if (be16_to_cpu(md->signature) != MAC_DRIVER_MAGIC) {
48 		put_dev_sector(sect);
49 		return 0;
50 	}
51 	secsize = be16_to_cpu(md->block_size);
52 	put_dev_sector(sect);
53 	datasize = round_down(secsize, 512);
54 	data = read_part_sector(state, datasize / 512, &sect);
55 	if (!data)
56 		return -1;
57 	partoffset = secsize % 512;
58 	if (partoffset + sizeof(*part) > datasize)
59 		return -1;
60 	part = (struct mac_partition *) (data + partoffset);
61 	if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) {
62 		put_dev_sector(sect);
63 		return 0;		/* not a MacOS disk */
64 	}
65 	blocks_in_map = be32_to_cpu(part->map_count);
66 	if (blocks_in_map < 0 || blocks_in_map >= DISK_MAX_PARTS) {
67 		put_dev_sector(sect);
68 		return 0;
69 	}
70 
71 	if (blocks_in_map >= state->limit)
72 		blocks_in_map = state->limit - 1;
73 
74 	strlcat(state->pp_buf, " [mac]", PAGE_SIZE);
75 	for (slot = 1; slot <= blocks_in_map; ++slot) {
76 		int pos = slot * secsize;
77 		put_dev_sector(sect);
78 		data = read_part_sector(state, pos/512, &sect);
79 		if (!data)
80 			return -1;
81 		part = (struct mac_partition *) (data + pos%512);
82 		if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC)
83 			break;
84 		put_partition(state, slot,
85 			be32_to_cpu(part->start_block) * (secsize/512),
86 			be32_to_cpu(part->block_count) * (secsize/512));
87 
88 		if (!strncasecmp(part->type, "Linux_RAID", 10))
89 			state->parts[slot].flags = ADDPART_FLAG_RAID;
90 #ifdef CONFIG_PPC_PMAC
91 		/*
92 		 * If this is the first bootable partition, tell the
93 		 * setup code, in case it wants to make this the root.
94 		 */
95 		if (machine_is(powermac)) {
96 			int goodness = 0;
97 
98 			mac_fix_string(part->processor, 16);
99 			mac_fix_string(part->name, 32);
100 			mac_fix_string(part->type, 32);
101 
102 			if ((be32_to_cpu(part->status) & MAC_STATUS_BOOTABLE)
103 			    && strcasecmp(part->processor, "powerpc") == 0)
104 				goodness++;
105 
106 			if (strcasecmp(part->type, "Apple_UNIX_SVR2") == 0
107 			    || (strncasecmp(part->type, "Linux", 5) == 0
108 			        && strcasecmp(part->type, "Linux_swap") != 0)) {
109 				int i, l;
110 
111 				goodness++;
112 				l = strlen(part->name);
113 				if (strcmp(part->name, "/") == 0)
114 					goodness++;
115 				for (i = 0; i <= l - 4; ++i) {
116 					if (strncasecmp(part->name + i, "root",
117 						     4) == 0) {
118 						goodness += 2;
119 						break;
120 					}
121 				}
122 				if (strncasecmp(part->name, "swap", 4) == 0)
123 					goodness--;
124 			}
125 
126 			if (goodness > found_root_goodness) {
127 				found_root = slot;
128 				found_root_goodness = goodness;
129 			}
130 		}
131 #endif /* CONFIG_PPC_PMAC */
132 	}
133 #ifdef CONFIG_PPC_PMAC
134 	if (found_root_goodness)
135 		note_bootable_part(state->bdev->bd_dev, found_root,
136 				   found_root_goodness);
137 #endif
138 
139 	put_dev_sector(sect);
140 	strlcat(state->pp_buf, "\n", PAGE_SIZE);
141 	return 1;
142 }
143