BUG_ON() Conversion in mm/mmap.c
[linux-2.6] / fs / partitions / amiga.c
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 #include <linux/types.h>
11 #include <linux/affs_hardblocks.h>
12
13 #include "check.h"
14 #include "amiga.h"
15
16 static __inline__ u32
17 checksum_block(__be32 *m, int size)
18 {
19         u32 sum = 0;
20
21         while (size--)
22                 sum += be32_to_cpu(*m++);
23         return sum;
24 }
25
26 int
27 amiga_partition(struct parsed_partitions *state, struct block_device *bdev)
28 {
29         Sector sect;
30         unsigned char *data;
31         struct RigidDiskBlock *rdb;
32         struct PartitionBlock *pb;
33         int start_sect, nr_sects, blk, part, res = 0;
34         int blksize = 1;        /* Multiplier for disk block size */
35         int slot = 1;
36         char b[BDEVNAME_SIZE];
37
38         for (blk = 0; ; blk++, put_dev_sector(sect)) {
39                 if (blk == RDB_ALLOCATION_LIMIT)
40                         goto rdb_done;
41                 data = read_dev_sector(bdev, blk, &sect);
42                 if (!data) {
43                         if (warn_no_part)
44                                 printk("Dev %s: unable to read RDB block %d\n",
45                                        bdevname(bdev, b), blk);
46                         goto rdb_done;
47                 }
48                 if (*(__be32 *)data != cpu_to_be32(IDNAME_RIGIDDISK))
49                         continue;
50
51                 rdb = (struct RigidDiskBlock *)data;
52                 if (checksum_block((__be32 *)data, be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F) == 0)
53                         break;
54                 /* Try again with 0xdc..0xdf zeroed, Windows might have
55                  * trashed it.
56                  */
57                 *(__be32 *)(data+0xdc) = 0;
58                 if (checksum_block((__be32 *)data,
59                                 be32_to_cpu(rdb->rdb_SummedLongs) & 0x7F)==0) {
60                         printk("Warning: Trashed word at 0xd0 in block %d "
61                                 "ignored in checksum calculation\n",blk);
62                         break;
63                 }
64
65                 printk("Dev %s: RDB in block %d has bad checksum\n",
66                                bdevname(bdev, b), blk);
67         }
68
69         /* blksize is blocks per 512 byte standard block */
70         blksize = be32_to_cpu( rdb->rdb_BlockBytes ) / 512;
71
72         printk(" RDSK (%d)", blksize * 512);    /* Be more informative */
73         blk = be32_to_cpu(rdb->rdb_PartitionList);
74         put_dev_sector(sect);
75         for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) {
76                 blk *= blksize; /* Read in terms partition table understands */
77                 data = read_dev_sector(bdev, blk, &sect);
78                 if (!data) {
79                         if (warn_no_part)
80                                 printk("Dev %s: unable to read partition block %d\n",
81                                        bdevname(bdev, b), blk);
82                         goto rdb_done;
83                 }
84                 pb  = (struct PartitionBlock *)data;
85                 blk = be32_to_cpu(pb->pb_Next);
86                 if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION))
87                         continue;
88                 if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 )
89                         continue;
90
91                 /* Tell Kernel about it */
92
93                 nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
94                             be32_to_cpu(pb->pb_Environment[9])) *
95                            be32_to_cpu(pb->pb_Environment[3]) *
96                            be32_to_cpu(pb->pb_Environment[5]) *
97                            blksize;
98                 if (!nr_sects)
99                         continue;
100                 start_sect = be32_to_cpu(pb->pb_Environment[9]) *
101                              be32_to_cpu(pb->pb_Environment[3]) *
102                              be32_to_cpu(pb->pb_Environment[5]) *
103                              blksize;
104                 put_partition(state,slot++,start_sect,nr_sects);
105                 {
106                         /* Be even more informative to aid mounting */
107                         char dostype[4];
108                         __be32 *dt = (__be32 *)dostype;
109                         *dt = pb->pb_Environment[16];
110                         if (dostype[3] < ' ')
111                                 printk(" (%c%c%c^%c)",
112                                         dostype[0], dostype[1],
113                                         dostype[2], dostype[3] + '@' );
114                         else
115                                 printk(" (%c%c%c%c)",
116                                         dostype[0], dostype[1],
117                                         dostype[2], dostype[3]);
118                         printk("(res %d spb %d)",
119                                 be32_to_cpu(pb->pb_Environment[6]),
120                                 be32_to_cpu(pb->pb_Environment[4]));
121                 }
122                 res = 1;
123         }
124         printk("\n");
125
126 rdb_done:
127         return res;
128 }