[net-next-2.6.git] / fs / partitions / acorn.c

/*
 *  linux/fs/partitions/acorn.c
 *
 *  Copyright (c) 1996-2000 Russell King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  Scan ADFS partitions on hard disk drives.  Unfortunately, there
 *  isn't a standard for partitioning drives on Acorn machines, so
 *  every single manufacturer of SCSI and IDE cards created their own
 *  method.
 */
#include <linux/buffer_head.h>
#include <linux/adfs_fs.h>

#include "check.h"
#include "acorn.h"

/*
 * Partition types. (Oh for reusability)
 */
#define PARTITION_RISCIX_MFM	1
#define PARTITION_RISCIX_SCSI	2
#define PARTITION_LINUX		9

#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
	defined(CONFIG_ACORN_PARTITION_ADFS)
static struct adfs_discrecord *
adfs_partition(struct parsed_partitions *state, char *name, char *data,
	       unsigned long first_sector, int slot)
{
	struct adfs_discrecord *dr;
	unsigned int nr_sects;

	if (adfs_checkbblk(data))
		return NULL;

	dr = (struct adfs_discrecord *)(data + 0x1c0);

	if (dr->disc_size == 0 && dr->disc_size_high == 0)
		return NULL;

	nr_sects = (le32_to_cpu(dr->disc_size_high) << 23) |
		   (le32_to_cpu(dr->disc_size) >> 9);

	if (name)
		printk(" [%s]", name);
	put_partition(state, slot, first_sector, nr_sects);
	return dr;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_RISCIX

struct riscix_part {
	__le32	start;
	__le32	length;
	__le32	one;
	char	name[16];
};

struct riscix_record {
	__le32	magic;
#define RISCIX_MAGIC	cpu_to_le32(0x4a657320)
	__le32	date;
	struct riscix_part part[8];
};

#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
	defined(CONFIG_ACORN_PARTITION_ADFS)
static int riscix_partition(struct parsed_partitions *state,
			    unsigned long first_sect, int slot,
			    unsigned long nr_sects)
{
	Sector sect;
	struct riscix_record *rr;
	
	rr = read_part_sector(state, first_sect, &sect);
	if (!rr)
		return -1;

	printk(" [RISCiX]");


	if (rr->magic == RISCIX_MAGIC) {
		unsigned long size = nr_sects > 2 ? 2 : nr_sects;
		int part;

		printk(" <");

		put_partition(state, slot++, first_sect, size);
		for (part = 0; part < 8; part++) {
			if (rr->part[part].one &&
			    memcmp(rr->part[part].name, "All\0", 4)) {
				put_partition(state, slot++,
					le32_to_cpu(rr->part[part].start),
					le32_to_cpu(rr->part[part].length));
				printk("(%s)", rr->part[part].name);
			}
		}

		printk(" >\n");
	} else {
		put_partition(state, slot++, first_sect, nr_sects);
	}

	put_dev_sector(sect);
	return slot;
}
#endif
#endif

#define LINUX_NATIVE_MAGIC 0xdeafa1de
#define LINUX_SWAP_MAGIC   0xdeafab1e

struct linux_part {
	__le32 magic;
	__le32 start_sect;
	__le32 nr_sects;
};

#if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
	defined(CONFIG_ACORN_PARTITION_ADFS)
static int linux_partition(struct parsed_partitions *state,
			   unsigned long first_sect, int slot,
			   unsigned long nr_sects)
{
	Sector sect;
	struct linux_part *linuxp;
	unsigned long size = nr_sects > 2 ? 2 : nr_sects;

	printk(" [Linux]");

	put_partition(state, slot++, first_sect, size);

	linuxp = read_part_sector(state, first_sect, &sect);
	if (!linuxp)
		return -1;

	printk(" <");
	while (linuxp->magic == cpu_to_le32(LINUX_NATIVE_MAGIC) ||
	       linuxp->magic == cpu_to_le32(LINUX_SWAP_MAGIC)) {
		if (slot == state->limit)
			break;
		put_partition(state, slot++, first_sect +
				 le32_to_cpu(linuxp->start_sect),
				 le32_to_cpu(linuxp->nr_sects));
		linuxp ++;
	}
	printk(" >");

	put_dev_sector(sect);
	return slot;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_CUMANA
int adfspart_check_CUMANA(struct parsed_partitions *state)
{
	unsigned long first_sector = 0;
	unsigned int start_blk = 0;
	Sector sect;
	unsigned char *data;
	char *name = "CUMANA/ADFS";
	int first = 1;
	int slot = 1;

	/*
	 * Try Cumana style partitions - sector 6 contains ADFS boot block
	 * with pointer to next 'drive'.
	 *
	 * There are unknowns in this code - is the 'cylinder number' of the
	 * next partition relative to the start of this one - I'm assuming
	 * it is.
	 *
	 * Also, which ID did Cumana use?
	 *
	 * This is totally unfinished, and will require more work to get it
	 * going. Hence it is totally untested.
	 */
	do {
		struct adfs_discrecord *dr;
		unsigned int nr_sects;

		data = read_part_sector(state, start_blk * 2 + 6, &sect);
		if (!data)
			return -1;

		if (slot == state->limit)
			break;

		dr = adfs_partition(state, name, data, first_sector, slot++);
		if (!dr)
			break;

		name = NULL;

		nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
			   (dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
			   dr->secspertrack;

		if (!nr_sects)
			break;

		first = 0;
		first_sector += nr_sects;
		start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
		nr_sects = 0; /* hmm - should be partition size */

		switch (data[0x1fc] & 15) {
		case 0: /* No partition / ADFS? */
			break;

#ifdef CONFIG_ACORN_PARTITION_RISCIX
		case PARTITION_RISCIX_SCSI:
			/* RISCiX - we don't know how to find the next one. */
			slot = riscix_partition(state, first_sector, slot,
						nr_sects);
			break;
#endif

		case PARTITION_LINUX:
			slot = linux_partition(state, first_sector, slot,
					       nr_sects);
			break;
		}
		put_dev_sector(sect);
		if (slot == -1)
			return -1;
	} while (1);
	put_dev_sector(sect);
	return first ? 0 : 1;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_ADFS
/*
 * Purpose: allocate ADFS partitions.
 *
 * Params : hd		- pointer to gendisk structure to store partition info.
 *	    dev		- device number to access.
 *
 * Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
 *
 * Alloc  : hda  = whole drive
 *	    hda1 = ADFS partition on first drive.
 *	    hda2 = non-ADFS partition.
 */
int adfspart_check_ADFS(struct parsed_partitions *state)
{
	unsigned long start_sect, nr_sects, sectscyl, heads;
	Sector sect;
	unsigned char *data;
	struct adfs_discrecord *dr;
	unsigned char id;
	int slot = 1;

	data = read_part_sector(state, 6, &sect);
	if (!data)
		return -1;

	dr = adfs_partition(state, "ADFS", data, 0, slot++);
	if (!dr) {
		put_dev_sector(sect);
    		return 0;
	}

	heads = dr->heads + ((dr->lowsector >> 6) & 1);
	sectscyl = dr->secspertrack * heads;
	start_sect = ((data[0x1fe] << 8) + data[0x1fd]) * sectscyl;
	id = data[0x1fc] & 15;
	put_dev_sector(sect);

	/*
	 * Work out start of non-adfs partition.
	 */
	nr_sects = (state->bdev->bd_inode->i_size >> 9) - start_sect;

	if (start_sect) {
		switch (id) {
#ifdef CONFIG_ACORN_PARTITION_RISCIX
		case PARTITION_RISCIX_SCSI:
		case PARTITION_RISCIX_MFM:
			slot = riscix_partition(state, start_sect, slot,
						nr_sects);
			break;
#endif

		case PARTITION_LINUX:
			slot = linux_partition(state, start_sect, slot,
					       nr_sects);
			break;
		}
	}
	printk("\n");
	return 1;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_ICS

struct ics_part {
	__le32 start;
	__le32 size;
};

static int adfspart_check_ICSLinux(struct parsed_partitions *state,
				   unsigned long block)
{
	Sector sect;
	unsigned char *data = read_part_sector(state, block, &sect);
	int result = 0;

	if (data) {
		if (memcmp(data, "LinuxPart", 9) == 0)
			result = 1;
		put_dev_sector(sect);
	}

	return result;
}

/*
 * Check for a valid ICS partition using the checksum.
 */
static inline int valid_ics_sector(const unsigned char *data)
{
	unsigned long sum;
	int i;

	for (i = 0, sum = 0x50617274; i < 508; i++)
		sum += data[i];

	sum -= le32_to_cpu(*(__le32 *)(&data[508]));

	return sum == 0;
}

/*
 * Purpose: allocate ICS partitions.
 * Params : hd		- pointer to gendisk structure to store partition info.
 *	    dev		- device number to access.
 * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
 * Alloc  : hda  = whole drive
 *	    hda1 = ADFS partition 0 on first drive.
 *	    hda2 = ADFS partition 1 on first drive.
 *		..etc..
 */
int adfspart_check_ICS(struct parsed_partitions *state)
{
	const unsigned char *data;
	const struct ics_part *p;
	int slot;
	Sector sect;

	/*
	 * Try ICS style partitions - sector 0 contains partition info.
	 */
	data = read_part_sector(state, 0, &sect);
	if (!data)
	    	return -1;

	if (!valid_ics_sector(data)) {
	    	put_dev_sector(sect);
		return 0;
	}

	printk(" [ICS]");

	for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
		u32 start = le32_to_cpu(p->start);
		s32 size = le32_to_cpu(p->size); /* yes, it's signed. */

		if (slot == state->limit)
			break;

		/*
		 * Negative sizes tell the RISC OS ICS driver to ignore
		 * this partition - in effect it says that this does not
		 * contain an ADFS filesystem.
		 */
		if (size < 0) {
			size = -size;

			/*
			 * Our own extension - We use the first sector
			 * of the partition to identify what type this
			 * partition is.  We must not make this visible
			 * to the filesystem.
			 */
			if (size > 1 && adfspart_check_ICSLinux(state, start)) {
				start += 1;
				size -= 1;
			}
		}

		if (size)
			put_partition(state, slot++, start, size);
	}

	put_dev_sector(sect);
	printk("\n");
	return 1;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_POWERTEC
struct ptec_part {
	__le32 unused1;
	__le32 unused2;
	__le32 start;
	__le32 size;
	__le32 unused5;
	char type[8];
};

static inline int valid_ptec_sector(const unsigned char *data)
{
	unsigned char checksum = 0x2a;
	int i;

	/*
	 * If it looks like a PC/BIOS partition, then it
	 * probably isn't PowerTec.
	 */
	if (data[510] == 0x55 && data[511] == 0xaa)
		return 0;

	for (i = 0; i < 511; i++)
		checksum += data[i];

	return checksum == data[511];
}

/*
 * Purpose: allocate ICS partitions.
 * Params : hd		- pointer to gendisk structure to store partition info.
 *	    dev		- device number to access.
 * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
 * Alloc  : hda  = whole drive
 *	    hda1 = ADFS partition 0 on first drive.
 *	    hda2 = ADFS partition 1 on first drive.
 *		..etc..
 */
int adfspart_check_POWERTEC(struct parsed_partitions *state)
{
	Sector sect;
	const unsigned char *data;
	const struct ptec_part *p;
	int slot = 1;
	int i;

	data = read_part_sector(state, 0, &sect);
	if (!data)
		return -1;

	if (!valid_ptec_sector(data)) {
		put_dev_sector(sect);
		return 0;
	}

	printk(" [POWERTEC]");

	for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
		u32 start = le32_to_cpu(p->start);
		u32 size = le32_to_cpu(p->size);

		if (size)
			put_partition(state, slot++, start, size);
	}

	put_dev_sector(sect);
	printk("\n");
	return 1;
}
#endif

#ifdef CONFIG_ACORN_PARTITION_EESOX
struct eesox_part {
	char	magic[6];
	char	name[10];
	__le32	start;
	__le32	unused6;
	__le32	unused7;
	__le32	unused8;
};

/*
 * Guess who created this format?
 */
static const char eesox_name[] = {
	'N', 'e', 'i', 'l', ' ',
	'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
};

/*
 * EESOX SCSI partition format.
 *
 * This is a goddamned awful partition format.  We don't seem to store
 * the size of the partition in this table, only the start addresses.
 *
 * There are two possibilities where the size comes from:
 *  1. The individual ADFS boot block entries that are placed on the disk.
 *  2. The start address of the next entry.
 */
int adfspart_check_EESOX(struct parsed_partitions *state)
{
	Sector sect;
	const unsigned char *data;
	unsigned char buffer[256];
	struct eesox_part *p;
	sector_t start = 0;
	int i, slot = 1;

	data = read_part_sector(state, 7, &sect);
	if (!data)
		return -1;

	/*
	 * "Decrypt" the partition table.  God knows why...
	 */
	for (i = 0; i < 256; i++)
		buffer[i] = data[i] ^ eesox_name[i & 15];

	put_dev_sector(sect);

	for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
		sector_t next;

		if (memcmp(p->magic, "Eesox", 6))
			break;

		next = le32_to_cpu(p->start);
		if (i)
			put_partition(state, slot++, start, next - start);
		start = next;
	}

	if (i != 0) {
		sector_t size;

		size = get_capacity(state->bdev->bd_disk);
		put_partition(state, slot++, start, size - start);
		printk("\n");
	}

	return i ? 1 : 0;
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/partitions/acorn.c
	3	*
	4	* Copyright (c) 1996-2000 Russell King.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*
	10	* Scan ADFS partitions on hard disk drives. Unfortunately, there
	11	* isn't a standard for partitioning drives on Acorn machines, so
	12	* every single manufacturer of SCSI and IDE cards created their own
	13	* method.
	14	*/
1da177e4 LT	15	#include <linux/buffer_head.h>
	16	#include <linux/adfs_fs.h>
	17
	18	#include "check.h"
	19	#include "acorn.h"
	20
	21	/*
	22	* Partition types. (Oh for reusability)
	23	*/
	24	#define PARTITION_RISCIX_MFM 1
	25	#define PARTITION_RISCIX_SCSI 2
	26	#define PARTITION_LINUX 9
	27
d05e96fe DG	28	#if defined(CONFIG_ACORN_PARTITION_CUMANA) \|\| \
d05e96fe DG	29	defined(CONFIG_ACORN_PARTITION_ADFS)
1da177e4 LT	30	static struct adfs_discrecord *
	31	adfs_partition(struct parsed_partitions state, char name, char *data,
	32	unsigned long first_sector, int slot)
	33	{
	34	struct adfs_discrecord *dr;
	35	unsigned int nr_sects;
	36
	37	if (adfs_checkbblk(data))
	38	return NULL;
	39
	40	dr = (struct adfs_discrecord *)(data + 0x1c0);
	41
	42	if (dr->disc_size == 0 && dr->disc_size_high == 0)
	43	return NULL;
	44
	45	nr_sects = (le32_to_cpu(dr->disc_size_high) << 23) \|
	46	(le32_to_cpu(dr->disc_size) >> 9);
	47
	48	if (name)
	49	printk(" [%s]", name);
	50	put_partition(state, slot, first_sector, nr_sects);
	51	return dr;
	52	}
d05e96fe	53	#endif
1da177e4 LT	54
	55	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	56
	57	struct riscix_part {
	58	__le32 start;
	59	__le32 length;
	60	__le32 one;
	61	char name[16];
	62	};
	63
	64	struct riscix_record {
	65	__le32 magic;
	66	#define RISCIX_MAGIC cpu_to_le32(0x4a657320)
	67	__le32 date;
	68	struct riscix_part part[8];
	69	};
	70
d05e96fe DG	71	#if defined(CONFIG_ACORN_PARTITION_CUMANA) \|\| \
d05e96fe DG	72	defined(CONFIG_ACORN_PARTITION_ADFS)
1493bf21 TH	73	static int riscix_partition(struct parsed_partitions *state,
	74	unsigned long first_sect, int slot,
	75	unsigned long nr_sects)
1da177e4 LT	76	{
	77	Sector sect;
	78	struct riscix_record *rr;
	79
1493bf21	80	rr = read_part_sector(state, first_sect, &sect);
1da177e4 LT	81	if (!rr)
	82	return -1;
	83
	84	printk(" [RISCiX]");
	85
	86
	87	if (rr->magic == RISCIX_MAGIC) {
	88	unsigned long size = nr_sects > 2 ? 2 : nr_sects;
	89	int part;
	90
	91	printk(" <");
	92
	93	put_partition(state, slot++, first_sect, size);
	94	for (part = 0; part < 8; part++) {
	95	if (rr->part[part].one &&
	96	memcmp(rr->part[part].name, "All\0", 4)) {
	97	put_partition(state, slot++,
	98	le32_to_cpu(rr->part[part].start),
	99	le32_to_cpu(rr->part[part].length));
	100	printk("(%s)", rr->part[part].name);
	101	}
	102	}
	103
	104	printk(" >\n");
	105	} else {
	106	put_partition(state, slot++, first_sect, nr_sects);
	107	}
	108
	109	put_dev_sector(sect);
	110	return slot;
	111	}
	112	#endif
d05e96fe	113	#endif
1da177e4 LT	114
	115	#define LINUX_NATIVE_MAGIC 0xdeafa1de
	116	#define LINUX_SWAP_MAGIC 0xdeafab1e
	117
	118	struct linux_part {
	119	__le32 magic;
	120	__le32 start_sect;
	121	__le32 nr_sects;
	122	};
	123
d05e96fe DG	124	#if defined(CONFIG_ACORN_PARTITION_CUMANA) \|\| \
d05e96fe DG	125	defined(CONFIG_ACORN_PARTITION_ADFS)
1493bf21 TH	126	static int linux_partition(struct parsed_partitions *state,
	127	unsigned long first_sect, int slot,
	128	unsigned long nr_sects)
1da177e4 LT	129	{
	130	Sector sect;
	131	struct linux_part *linuxp;
	132	unsigned long size = nr_sects > 2 ? 2 : nr_sects;
	133
	134	printk(" [Linux]");
	135
	136	put_partition(state, slot++, first_sect, size);
	137
1493bf21	138	linuxp = read_part_sector(state, first_sect, &sect);
1da177e4 LT	139	if (!linuxp)
	140	return -1;
	141
	142	printk(" <");
	143	while (linuxp->magic == cpu_to_le32(LINUX_NATIVE_MAGIC) \|\|
	144	linuxp->magic == cpu_to_le32(LINUX_SWAP_MAGIC)) {
	145	if (slot == state->limit)
	146	break;
	147	put_partition(state, slot++, first_sect +
	148	le32_to_cpu(linuxp->start_sect),
	149	le32_to_cpu(linuxp->nr_sects));
	150	linuxp ++;
	151	}
	152	printk(" >");
	153
	154	put_dev_sector(sect);
	155	return slot;
	156	}
d05e96fe	157	#endif
1da177e4 LT	158
1da177e4 LT	159	#ifdef CONFIG_ACORN_PARTITION_CUMANA
1493bf21	160	int adfspart_check_CUMANA(struct parsed_partitions *state)
1da177e4 LT	161	{
	162	unsigned long first_sector = 0;
	163	unsigned int start_blk = 0;
	164	Sector sect;
	165	unsigned char *data;
	166	char *name = "CUMANA/ADFS";
	167	int first = 1;
	168	int slot = 1;
	169
	170	/*
	171	* Try Cumana style partitions - sector 6 contains ADFS boot block
	172	* with pointer to next 'drive'.
	173	*
	174	* There are unknowns in this code - is the 'cylinder number' of the
	175	* next partition relative to the start of this one - I'm assuming
	176	* it is.
	177	*
	178	* Also, which ID did Cumana use?
	179	*
	180	* This is totally unfinished, and will require more work to get it
	181	* going. Hence it is totally untested.
	182	*/
	183	do {
	184	struct adfs_discrecord *dr;
	185	unsigned int nr_sects;
	186
1493bf21	187	data = read_part_sector(state, start_blk * 2 + 6, &sect);
1da177e4 LT	188	if (!data)
	189	return -1;
	190
	191	if (slot == state->limit)
	192	break;
	193
	194	dr = adfs_partition(state, name, data, first_sector, slot++);
	195	if (!dr)
	196	break;
	197
	198	name = NULL;
	199
	200	nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
	201	(dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
	202	dr->secspertrack;
	203
	204	if (!nr_sects)
	205	break;
	206
	207	first = 0;
	208	first_sector += nr_sects;
	209	start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
	210	nr_sects = 0; /* hmm - should be partition size */
	211
	212	switch (data[0x1fc] & 15) {
	213	case 0: /* No partition / ADFS? */
	214	break;
	215
	216	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	217	case PARTITION_RISCIX_SCSI:
	218	/* RISCiX - we don't know how to find the next one. */
1493bf21 TH	219	slot = riscix_partition(state, first_sector, slot,
1493bf21 TH	220	nr_sects);
1da177e4 LT	221	break;
	222	#endif
	223
	224	case PARTITION_LINUX:
1493bf21 TH	225	slot = linux_partition(state, first_sector, slot,
1493bf21 TH	226	nr_sects);
1da177e4 LT	227	break;
	228	}
	229	put_dev_sector(sect);
	230	if (slot == -1)
	231	return -1;
	232	} while (1);
	233	put_dev_sector(sect);
	234	return first ? 0 : 1;
	235	}
	236	#endif
	237
	238	#ifdef CONFIG_ACORN_PARTITION_ADFS
	239	/*
	240	* Purpose: allocate ADFS partitions.
	241	*
	242	* Params : hd - pointer to gendisk structure to store partition info.
	243	* dev - device number to access.
	244	*
	245	* Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
	246	*
	247	* Alloc : hda = whole drive
	248	* hda1 = ADFS partition on first drive.
	249	* hda2 = non-ADFS partition.
	250	*/
1493bf21	251	int adfspart_check_ADFS(struct parsed_partitions *state)
1da177e4 LT	252	{
	253	unsigned long start_sect, nr_sects, sectscyl, heads;
	254	Sector sect;
	255	unsigned char *data;
	256	struct adfs_discrecord *dr;
	257	unsigned char id;
	258	int slot = 1;
	259
1493bf21	260	data = read_part_sector(state, 6, &sect);
1da177e4 LT	261	if (!data)
	262	return -1;
	263
	264	dr = adfs_partition(state, "ADFS", data, 0, slot++);
	265	if (!dr) {
	266	put_dev_sector(sect);
	267	return 0;
	268	}
	269
	270	heads = dr->heads + ((dr->lowsector >> 6) & 1);
	271	sectscyl = dr->secspertrack * heads;
	272	start_sect = ((data[0x1fe] << 8) + data[0x1fd]) * sectscyl;
	273	id = data[0x1fc] & 15;
	274	put_dev_sector(sect);
	275
1da177e4 LT	276	/*
	277	* Work out start of non-adfs partition.
	278	*/
1493bf21	279	nr_sects = (state->bdev->bd_inode->i_size >> 9) - start_sect;
1da177e4 LT	280
	281	if (start_sect) {
	282	switch (id) {
	283	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	284	case PARTITION_RISCIX_SCSI:
	285	case PARTITION_RISCIX_MFM:
1493bf21 TH	286	slot = riscix_partition(state, start_sect, slot,
1493bf21 TH	287	nr_sects);
1da177e4 LT	288	break;
	289	#endif
	290
	291	case PARTITION_LINUX:
1493bf21 TH	292	slot = linux_partition(state, start_sect, slot,
1493bf21 TH	293	nr_sects);
1da177e4 LT	294	break;
	295	}
	296	}
	297	printk("\n");
	298	return 1;
	299	}
	300	#endif
	301
	302	#ifdef CONFIG_ACORN_PARTITION_ICS
	303
	304	struct ics_part {
	305	__le32 start;
	306	__le32 size;
	307	};
	308
1493bf21 TH	309	static int adfspart_check_ICSLinux(struct parsed_partitions *state,
1493bf21 TH	310	unsigned long block)
1da177e4 LT	311	{
1da177e4 LT	312	Sector sect;
1493bf21	313	unsigned char *data = read_part_sector(state, block, &sect);
1da177e4 LT	314	int result = 0;
	315
	316	if (data) {
	317	if (memcmp(data, "LinuxPart", 9) == 0)
	318	result = 1;
	319	put_dev_sector(sect);
	320	}
	321
	322	return result;
	323	}
	324
	325	/*
	326	* Check for a valid ICS partition using the checksum.
	327	*/
	328	static inline int valid_ics_sector(const unsigned char *data)
	329	{
	330	unsigned long sum;
	331	int i;
	332
	333	for (i = 0, sum = 0x50617274; i < 508; i++)
	334	sum += data[i];
	335
	336	sum -= le32_to_cpu((__le32 )(&data[508]));
	337
	338	return sum == 0;
	339	}
	340
	341	/*
	342	* Purpose: allocate ICS partitions.
	343	* Params : hd - pointer to gendisk structure to store partition info.
	344	* dev - device number to access.
	345	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
	346	* Alloc : hda = whole drive
	347	* hda1 = ADFS partition 0 on first drive.
	348	* hda2 = ADFS partition 1 on first drive.
	349	* ..etc..
	350	*/
1493bf21	351	int adfspart_check_ICS(struct parsed_partitions *state)
1da177e4 LT	352	{
	353	const unsigned char *data;
	354	const struct ics_part *p;
	355	int slot;
	356	Sector sect;
	357
	358	/*
	359	* Try ICS style partitions - sector 0 contains partition info.
	360	*/
1493bf21	361	data = read_part_sector(state, 0, &sect);
1da177e4 LT	362	if (!data)
	363	return -1;
	364
	365	if (!valid_ics_sector(data)) {
	366	put_dev_sector(sect);
	367	return 0;
	368	}
	369
	370	printk(" [ICS]");
	371
	372	for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
	373	u32 start = le32_to_cpu(p->start);
	374	s32 size = le32_to_cpu(p->size); /* yes, it's signed. */
	375
	376	if (slot == state->limit)
	377	break;
	378
	379	/*
	380	* Negative sizes tell the RISC OS ICS driver to ignore
	381	* this partition - in effect it says that this does not
	382	* contain an ADFS filesystem.
	383	*/
	384	if (size < 0) {
	385	size = -size;
	386
	387	/*
	388	* Our own extension - We use the first sector
	389	* of the partition to identify what type this
	390	* partition is. We must not make this visible
	391	* to the filesystem.
	392	*/
1493bf21	393	if (size > 1 && adfspart_check_ICSLinux(state, start)) {
1da177e4 LT	394	start += 1;
	395	size -= 1;
	396	}
	397	}
	398
	399	if (size)
	400	put_partition(state, slot++, start, size);
	401	}
	402
	403	put_dev_sector(sect);
	404	printk("\n");
	405	return 1;
	406	}
	407	#endif
	408
	409	#ifdef CONFIG_ACORN_PARTITION_POWERTEC
	410	struct ptec_part {
	411	__le32 unused1;
	412	__le32 unused2;
	413	__le32 start;
	414	__le32 size;
	415	__le32 unused5;
	416	char type[8];
	417	};
	418
	419	static inline int valid_ptec_sector(const unsigned char *data)
	420	{
	421	unsigned char checksum = 0x2a;
	422	int i;
	423
	424	/*
	425	* If it looks like a PC/BIOS partition, then it
	426	* probably isn't PowerTec.
	427	*/
	428	if (data[510] == 0x55 && data[511] == 0xaa)
	429	return 0;
	430
	431	for (i = 0; i < 511; i++)
	432	checksum += data[i];
	433
	434	return checksum == data[511];
	435	}
	436
	437	/*
	438	* Purpose: allocate ICS partitions.
	439	* Params : hd - pointer to gendisk structure to store partition info.
	440	* dev - device number to access.
	441	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
	442	* Alloc : hda = whole drive
	443	* hda1 = ADFS partition 0 on first drive.
	444	* hda2 = ADFS partition 1 on first drive.
	445	* ..etc..
	446	*/
1493bf21	447	int adfspart_check_POWERTEC(struct parsed_partitions *state)
1da177e4 LT	448	{
	449	Sector sect;
	450	const unsigned char *data;
	451	const struct ptec_part *p;
	452	int slot = 1;
	453	int i;
	454
1493bf21	455	data = read_part_sector(state, 0, &sect);
1da177e4 LT	456	if (!data)
	457	return -1;
	458
	459	if (!valid_ptec_sector(data)) {
	460	put_dev_sector(sect);
	461	return 0;
	462	}
	463
	464	printk(" [POWERTEC]");
	465
	466	for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
	467	u32 start = le32_to_cpu(p->start);
	468	u32 size = le32_to_cpu(p->size);
	469
	470	if (size)
	471	put_partition(state, slot++, start, size);
	472	}
	473
	474	put_dev_sector(sect);
	475	printk("\n");
	476	return 1;
	477	}
	478	#endif
	479
	480	#ifdef CONFIG_ACORN_PARTITION_EESOX
	481	struct eesox_part {
	482	char magic[6];
	483	char name[10];
	484	__le32 start;
	485	__le32 unused6;
	486	__le32 unused7;
	487	__le32 unused8;
	488	};
	489
	490	/*
	491	* Guess who created this format?
	492	*/
	493	static const char eesox_name[] = {
	494	'N', 'e', 'i', 'l', ' ',
	495	'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
	496	};
	497
	498	/*
	499	* EESOX SCSI partition format.
	500	*
	501	* This is a goddamned awful partition format. We don't seem to store
	502	* the size of the partition in this table, only the start addresses.
	503	*
	504	* There are two possibilities where the size comes from:
	505	* 1. The individual ADFS boot block entries that are placed on the disk.
	506	* 2. The start address of the next entry.
	507	*/
1493bf21	508	int adfspart_check_EESOX(struct parsed_partitions *state)
1da177e4 LT	509	{
	510	Sector sect;
	511	const unsigned char *data;
	512	unsigned char buffer[256];
	513	struct eesox_part *p;
	514	sector_t start = 0;
	515	int i, slot = 1;
	516
1493bf21	517	data = read_part_sector(state, 7, &sect);
1da177e4 LT	518	if (!data)
	519	return -1;
	520
	521	/*
	522	* "Decrypt" the partition table. God knows why...
	523	*/
	524	for (i = 0; i < 256; i++)
	525	buffer[i] = data[i] ^ eesox_name[i & 15];
	526
	527	put_dev_sector(sect);
	528
	529	for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
	530	sector_t next;
	531
	532	if (memcmp(p->magic, "Eesox", 6))
	533	break;
	534
	535	next = le32_to_cpu(p->start);
	536	if (i)
	537	put_partition(state, slot++, start, next - start);
	538	start = next;
	539	}
	540
	541	if (i != 0) {
	542	sector_t size;
	543
1493bf21	544	size = get_capacity(state->bdev->bd_disk);
1da177e4 LT	545	put_partition(state, slot++, start, size - start);
	546	printk("\n");
	547	}
	548
	549	return i ? 1 : 0;
	550	}
	551	#endif