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/fs/partitions/amiga.c

https://bitbucket.org/cyanogenmod/android_kernel_asus_tf300t
C | 139 lines | 109 code | 15 blank | 15 comment | 21 complexity | 2fa02bcc0da3996ccf832b326ebe2cae MD5 | raw file
Possible License(s): LGPL-2.0, AGPL-1.0, GPL-2.0
  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
 16static __inline__ u32
 17checksum_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
 26int amiga_partition(struct parsed_partitions *state)
 27{
 28	Sector sect;
 29	unsigned char *data;
 30	struct RigidDiskBlock *rdb;
 31	struct PartitionBlock *pb;
 32	int start_sect, nr_sects, blk, part, res = 0;
 33	int blksize = 1;	/* Multiplier for disk block size */
 34	int slot = 1;
 35	char b[BDEVNAME_SIZE];
 36
 37	for (blk = 0; ; blk++, put_dev_sector(sect)) {
 38		if (blk == RDB_ALLOCATION_LIMIT)
 39			goto rdb_done;
 40		data = read_part_sector(state, blk, &sect);
 41		if (!data) {
 42			if (warn_no_part)
 43				printk("Dev %s: unable to read RDB block %d\n",
 44				       bdevname(state->bdev, b), blk);
 45			res = -1;
 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(state->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	{
 73		char tmp[7 + 10 + 1 + 1];
 74
 75		/* Be more informative */
 76		snprintf(tmp, sizeof(tmp), " RDSK (%d)", blksize * 512);
 77		strlcat(state->pp_buf, tmp, PAGE_SIZE);
 78	}
 79	blk = be32_to_cpu(rdb->rdb_PartitionList);
 80	put_dev_sector(sect);
 81	for (part = 1; blk>0 && part<=16; part++, put_dev_sector(sect)) {
 82		blk *= blksize;	/* Read in terms partition table understands */
 83		data = read_part_sector(state, blk, &sect);
 84		if (!data) {
 85			if (warn_no_part)
 86				printk("Dev %s: unable to read partition block %d\n",
 87				       bdevname(state->bdev, b), blk);
 88			res = -1;
 89			goto rdb_done;
 90		}
 91		pb  = (struct PartitionBlock *)data;
 92		blk = be32_to_cpu(pb->pb_Next);
 93		if (pb->pb_ID != cpu_to_be32(IDNAME_PARTITION))
 94			continue;
 95		if (checksum_block((__be32 *)pb, be32_to_cpu(pb->pb_SummedLongs) & 0x7F) != 0 )
 96			continue;
 97
 98		/* Tell Kernel about it */
 99
100		nr_sects = (be32_to_cpu(pb->pb_Environment[10]) + 1 -
101			    be32_to_cpu(pb->pb_Environment[9])) *
102			   be32_to_cpu(pb->pb_Environment[3]) *
103			   be32_to_cpu(pb->pb_Environment[5]) *
104			   blksize;
105		if (!nr_sects)
106			continue;
107		start_sect = be32_to_cpu(pb->pb_Environment[9]) *
108			     be32_to_cpu(pb->pb_Environment[3]) *
109			     be32_to_cpu(pb->pb_Environment[5]) *
110			     blksize;
111		put_partition(state,slot++,start_sect,nr_sects);
112		{
113			/* Be even more informative to aid mounting */
114			char dostype[4];
115			char tmp[42];
116
117			__be32 *dt = (__be32 *)dostype;
118			*dt = pb->pb_Environment[16];
119			if (dostype[3] < ' ')
120				snprintf(tmp, sizeof(tmp), " (%c%c%c^%c)",
121					dostype[0], dostype[1],
122					dostype[2], dostype[3] + '@' );
123			else
124				snprintf(tmp, sizeof(tmp), " (%c%c%c%c)",
125					dostype[0], dostype[1],
126					dostype[2], dostype[3]);
127			strlcat(state->pp_buf, tmp, PAGE_SIZE);
128			snprintf(tmp, sizeof(tmp), "(res %d spb %d)",
129				be32_to_cpu(pb->pb_Environment[6]),
130				be32_to_cpu(pb->pb_Environment[4]));
131			strlcat(state->pp_buf, tmp, PAGE_SIZE);
132		}
133		res = 1;
134	}
135	strlcat(state->pp_buf, "\n", PAGE_SIZE);
136
137rdb_done:
138	return res;
139}