xref: /openbmc/linux/block/partitions/amiga.c (revision 9cfc5c90)
1 /*
2  *  fs/partitions/amiga.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 #define pr_fmt(fmt) fmt
11 
12 #include <linux/types.h>
13 #include <linux/affs_hardblocks.h>
14 
15 #include "check.h"
16 #include "amiga.h"
17 
18 static __inline__ u32
19 checksum_block(__be32 *m, int size)
20 {
21 	u32 sum = 0;
22 
23 	while (size--)
24 		sum += be32_to_cpu(*m++);
25 	return sum;
26 }
27 
28 int amiga_partition(struct parsed_partitions *state)
29 {
30 	Sector sect;
31 	unsigned char *data;
32 	struct RigidDiskBlock *rdb;
33 	struct PartitionBlock *pb;
34 	int start_sect, nr_sects, blk, part, res = 0;
35 	int blksize = 1;	/* Multiplier for disk block size */
36 	int slot = 1;
37 	char b[BDEVNAME_SIZE];
38 
39 	for (blk = 0; ; blk++, put_dev_sector(sect)) {
40 		if (blk == RDB_ALLOCATION_LIMIT)
41 			goto rdb_done;
42 		data = read_part_sector(state, blk, &sect);
43 		if (!data) {
44 			if (warn_no_part)
45 				pr_err("Dev %s: unable to read RDB block %d\n",
46 				       bdevname(state->bdev, b), blk);
47 			res = -1;
48 			goto rdb_done;
49 		}
50 		if (*(__be32 *)data != cpu_to_be32(IDNAME_RIGIDDISK))
51 			continue;
52 
53 		rdb = (struct RigidDiskBlock *)data;
54 		if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F) == 0)
55 			break;
56 		/* Try again with 0xdc..0xdf zeroed, Windows might have
57 		 * trashed it.
58 		 */
59 		*(__be32 *)(data+0xdc) = 0;
60 		if (checksum_block((__be32 *)data,
61 				be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) {
62 			pr_err("Trashed word at 0xd0 in block %d ignored in checksum calculation\n",
63 			       blk);
64 			break;
65 		}
66 
67 		pr_err("Dev %s: RDB in block %d has bad checksum\n",
68 		       bdevname(state->bdev, b), blk);
69 	}
70 
71 	/* blksize is blocks per 512 byte standard block */
72 	blksize = be32_to_cpu( rdb->rdb_BlockBytes ) / 512;
73 
74 	{
75 		char tmp[7 + 10 + 1 + 1];
76 
77 		/* Be more informative */
78 		snprintf(tmp, sizeof(tmp), " RDSK (%d)", blksize * 512);
79 		strlcat(state->pp_buf, tmp, PAGE_SIZE);
80 	}
81 	blk = be32_to_cpu(rdb->rdb_PartitionList);
82 	put_dev_sector(sect);
83 	for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) {
84 		blk *= blksize;	/* Read in terms partition table understands */
85 		data = read_part_sector(state, blk, &sect);
86 		if (!data) {
87 			if (warn_no_part)
88 				pr_err("Dev %s: unable to read partition block %d\n",
89 				       bdevname(state->bdev, b), blk);
90 			res = -1;
91 			goto rdb_done;
92 		}
93 		pb  = (struct PartitionBlock *)data;
94 		blk = be32_to_cpu(pb->pb_Next);
95 		if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION))
96 			continue;
97 		if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 )
98 			continue;
99 
100 		/* Tell Kernel about it */
101 
102 		nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
103 			    be32_to_cpu(pb->pb_Environment[9])) *
104 			   be32_to_cpu(pb->pb_Environment[3]) *
105 			   be32_to_cpu(pb->pb_Environment[5]) *
106 			   blksize;
107 		if (!nr_sects)
108 			continue;
109 		start_sect = be32_to_cpu(pb->pb_Environment[9]) *
110 			     be32_to_cpu(pb->pb_Environment[3]) *
111 			     be32_to_cpu(pb->pb_Environment[5]) *
112 			     blksize;
113 		put_partition(state,slot++,start_sect,nr_sects);
114 		{
115 			/* Be even more informative to aid mounting */
116 			char dostype[4];
117 			char tmp[42];
118 
119 			__be32 *dt = (__be32 *)dostype;
120 			*dt = pb->pb_Environment[16];
121 			if (dostype[3] < ' ')
122 				snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)",
123 					dostype[0], dostype[1],
124 					dostype[2], dostype[3] + '@' );
125 			else
126 				snprintf(tmp, sizeof(tmp), " (%c%c%c%c)",
127 					dostype[0], dostype[1],
128 					dostype[2], dostype[3]);
129 			strlcat(state->pp_buf, tmp, PAGE_SIZE);
130 			snprintf(tmp, sizeof(tmp), "(res %d spb %d)",
131 				be32_to_cpu(pb->pb_Environment[6]),
132 				be32_to_cpu(pb->pb_Environment[4]));
133 			strlcat(state->pp_buf, tmp, PAGE_SIZE);
134 		}
135 		res = 1;
136 	}
137 	strlcat(state->pp_buf, "\n", PAGE_SIZE);
138 
139 rdb_done:
140 	return res;
141 }
142