[linux.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) {
		strlcat(state->pp_buf, " [", PAGE_SIZE);
		strlcat(state->pp_buf, name, PAGE_SIZE);
		strlcat(state->pp_buf, "]", PAGE_SIZE);
	}
	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;

	strlcat(state->pp_buf, " [RISCiX]", PAGE_SIZE);


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

		strlcat(state->pp_buf, " <", PAGE_SIZE);

		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));
				strlcat(state->pp_buf, "(", PAGE_SIZE);
				strlcat(state->pp_buf, rr->part[part].name, PAGE_SIZE);
				strlcat(state->pp_buf, ")", PAGE_SIZE);
			}
		}

		strlcat(state->pp_buf, " >\n", PAGE_SIZE);
	} 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;

	strlcat(state->pp_buf, " [Linux]", PAGE_SIZE);

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

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

	strlcat(state->pp_buf, " <", PAGE_SIZE);
	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 ++;
	}
	strlcat(state->pp_buf, " >", PAGE_SIZE);

	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;
		}
	}
	strlcat(state->pp_buf, "\n", PAGE_SIZE);
	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;
	}

	strlcat(state->pp_buf, " [ICS]", PAGE_SIZE);

	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);
	strlcat(state->pp_buf, "\n", PAGE_SIZE);
	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;
	}

	strlcat(state->pp_buf, " [POWERTEC]", PAGE_SIZE);

	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);
	strlcat(state->pp_buf, "\n", PAGE_SIZE);
	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);
		strlcat(state->pp_buf, "\n", PAGE_SIZE);
	}

	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
9c867fbe AD	48	if (name) {
	49	strlcat(state->pp_buf, " [", PAGE_SIZE);
	50	strlcat(state->pp_buf, name, PAGE_SIZE);
	51	strlcat(state->pp_buf, "]", PAGE_SIZE);
	52	}
1da177e4 LT	53	put_partition(state, slot, first_sector, nr_sects);
	54	return dr;
	55	}
d05e96fe	56	#endif
1da177e4 LT	57
	58	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	59
	60	struct riscix_part {
	61	__le32 start;
	62	__le32 length;
	63	__le32 one;
	64	char name[16];
	65	};
	66
	67	struct riscix_record {
	68	__le32 magic;
	69	#define RISCIX_MAGIC cpu_to_le32(0x4a657320)
	70	__le32 date;
	71	struct riscix_part part[8];
	72	};
	73
d05e96fe DG	74	#if defined(CONFIG_ACORN_PARTITION_CUMANA) \|\| \
d05e96fe DG	75	defined(CONFIG_ACORN_PARTITION_ADFS)
1493bf21 TH	76	static int riscix_partition(struct parsed_partitions *state,
	77	unsigned long first_sect, int slot,
	78	unsigned long nr_sects)
1da177e4 LT	79	{
	80	Sector sect;
	81	struct riscix_record *rr;
	82
1493bf21	83	rr = read_part_sector(state, first_sect, &sect);
1da177e4 LT	84	if (!rr)
	85	return -1;
	86
9c867fbe	87	strlcat(state->pp_buf, " [RISCiX]", PAGE_SIZE);
1da177e4 LT	88
	89
	90	if (rr->magic == RISCIX_MAGIC) {
	91	unsigned long size = nr_sects > 2 ? 2 : nr_sects;
	92	int part;
	93
9c867fbe	94	strlcat(state->pp_buf, " <", PAGE_SIZE);
1da177e4 LT	95
	96	put_partition(state, slot++, first_sect, size);
	97	for (part = 0; part < 8; part++) {
	98	if (rr->part[part].one &&
	99	memcmp(rr->part[part].name, "All\0", 4)) {
	100	put_partition(state, slot++,
	101	le32_to_cpu(rr->part[part].start),
	102	le32_to_cpu(rr->part[part].length));
9c867fbe AD	103	strlcat(state->pp_buf, "(", PAGE_SIZE);
	104	strlcat(state->pp_buf, rr->part[part].name, PAGE_SIZE);
	105	strlcat(state->pp_buf, ")", PAGE_SIZE);
1da177e4 LT	106	}
	107	}
	108
9c867fbe	109	strlcat(state->pp_buf, " >\n", PAGE_SIZE);
1da177e4 LT	110	} else {
	111	put_partition(state, slot++, first_sect, nr_sects);
	112	}
	113
	114	put_dev_sector(sect);
	115	return slot;
	116	}
	117	#endif
d05e96fe	118	#endif
1da177e4 LT	119
	120	#define LINUX_NATIVE_MAGIC 0xdeafa1de
	121	#define LINUX_SWAP_MAGIC 0xdeafab1e
	122
	123	struct linux_part {
	124	__le32 magic;
	125	__le32 start_sect;
	126	__le32 nr_sects;
	127	};
	128
d05e96fe DG	129	#if defined(CONFIG_ACORN_PARTITION_CUMANA) \|\| \
d05e96fe DG	130	defined(CONFIG_ACORN_PARTITION_ADFS)
1493bf21 TH	131	static int linux_partition(struct parsed_partitions *state,
	132	unsigned long first_sect, int slot,
	133	unsigned long nr_sects)
1da177e4 LT	134	{
	135	Sector sect;
	136	struct linux_part *linuxp;
	137	unsigned long size = nr_sects > 2 ? 2 : nr_sects;
	138
9c867fbe	139	strlcat(state->pp_buf, " [Linux]", PAGE_SIZE);
1da177e4 LT	140
	141	put_partition(state, slot++, first_sect, size);
	142
1493bf21	143	linuxp = read_part_sector(state, first_sect, &sect);
1da177e4 LT	144	if (!linuxp)
	145	return -1;
	146
9c867fbe	147	strlcat(state->pp_buf, " <", PAGE_SIZE);
1da177e4 LT	148	while (linuxp->magic == cpu_to_le32(LINUX_NATIVE_MAGIC) \|\|
	149	linuxp->magic == cpu_to_le32(LINUX_SWAP_MAGIC)) {
	150	if (slot == state->limit)
	151	break;
	152	put_partition(state, slot++, first_sect +
	153	le32_to_cpu(linuxp->start_sect),
	154	le32_to_cpu(linuxp->nr_sects));
	155	linuxp ++;
	156	}
9c867fbe	157	strlcat(state->pp_buf, " >", PAGE_SIZE);
1da177e4 LT	158
	159	put_dev_sector(sect);
	160	return slot;
	161	}
d05e96fe	162	#endif
1da177e4 LT	163
1da177e4 LT	164	#ifdef CONFIG_ACORN_PARTITION_CUMANA
1493bf21	165	int adfspart_check_CUMANA(struct parsed_partitions *state)
1da177e4 LT	166	{
	167	unsigned long first_sector = 0;
	168	unsigned int start_blk = 0;
	169	Sector sect;
	170	unsigned char *data;
	171	char *name = "CUMANA/ADFS";
	172	int first = 1;
	173	int slot = 1;
	174
	175	/*
	176	* Try Cumana style partitions - sector 6 contains ADFS boot block
	177	* with pointer to next 'drive'.
	178	*
	179	* There are unknowns in this code - is the 'cylinder number' of the
	180	* next partition relative to the start of this one - I'm assuming
	181	* it is.
	182	*
	183	* Also, which ID did Cumana use?
	184	*
	185	* This is totally unfinished, and will require more work to get it
	186	* going. Hence it is totally untested.
	187	*/
	188	do {
	189	struct adfs_discrecord *dr;
	190	unsigned int nr_sects;
	191
1493bf21	192	data = read_part_sector(state, start_blk * 2 + 6, &sect);
1da177e4 LT	193	if (!data)
	194	return -1;
	195
	196	if (slot == state->limit)
	197	break;
	198
	199	dr = adfs_partition(state, name, data, first_sector, slot++);
	200	if (!dr)
	201	break;
	202
	203	name = NULL;
	204
	205	nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
	206	(dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
	207	dr->secspertrack;
	208
	209	if (!nr_sects)
	210	break;
	211
	212	first = 0;
	213	first_sector += nr_sects;
	214	start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
	215	nr_sects = 0; /* hmm - should be partition size */
	216
	217	switch (data[0x1fc] & 15) {
	218	case 0: /* No partition / ADFS? */
	219	break;
	220
	221	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	222	case PARTITION_RISCIX_SCSI:
	223	/* RISCiX - we don't know how to find the next one. */
1493bf21 TH	224	slot = riscix_partition(state, first_sector, slot,
1493bf21 TH	225	nr_sects);
1da177e4 LT	226	break;
	227	#endif
	228
	229	case PARTITION_LINUX:
1493bf21 TH	230	slot = linux_partition(state, first_sector, slot,
1493bf21 TH	231	nr_sects);
1da177e4 LT	232	break;
	233	}
	234	put_dev_sector(sect);
	235	if (slot == -1)
	236	return -1;
	237	} while (1);
	238	put_dev_sector(sect);
	239	return first ? 0 : 1;
	240	}
	241	#endif
	242
	243	#ifdef CONFIG_ACORN_PARTITION_ADFS
	244	/*
	245	* Purpose: allocate ADFS partitions.
	246	*
	247	* Params : hd - pointer to gendisk structure to store partition info.
	248	* dev - device number to access.
	249	*
	250	* Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
	251	*
	252	* Alloc : hda = whole drive
	253	* hda1 = ADFS partition on first drive.
	254	* hda2 = non-ADFS partition.
	255	*/
1493bf21	256	int adfspart_check_ADFS(struct parsed_partitions *state)
1da177e4 LT	257	{
	258	unsigned long start_sect, nr_sects, sectscyl, heads;
	259	Sector sect;
	260	unsigned char *data;
	261	struct adfs_discrecord *dr;
	262	unsigned char id;
	263	int slot = 1;
	264
1493bf21	265	data = read_part_sector(state, 6, &sect);
1da177e4 LT	266	if (!data)
	267	return -1;
	268
	269	dr = adfs_partition(state, "ADFS", data, 0, slot++);
	270	if (!dr) {
	271	put_dev_sector(sect);
	272	return 0;
	273	}
	274
	275	heads = dr->heads + ((dr->lowsector >> 6) & 1);
	276	sectscyl = dr->secspertrack * heads;
	277	start_sect = ((data[0x1fe] << 8) + data[0x1fd]) * sectscyl;
	278	id = data[0x1fc] & 15;
	279	put_dev_sector(sect);
	280
1da177e4 LT	281	/*
	282	* Work out start of non-adfs partition.
	283	*/
1493bf21	284	nr_sects = (state->bdev->bd_inode->i_size >> 9) - start_sect;
1da177e4 LT	285
	286	if (start_sect) {
	287	switch (id) {
	288	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	289	case PARTITION_RISCIX_SCSI:
	290	case PARTITION_RISCIX_MFM:
1493bf21 TH	291	slot = riscix_partition(state, start_sect, slot,
1493bf21 TH	292	nr_sects);
1da177e4 LT	293	break;
	294	#endif
	295
	296	case PARTITION_LINUX:
1493bf21 TH	297	slot = linux_partition(state, start_sect, slot,
1493bf21 TH	298	nr_sects);
1da177e4 LT	299	break;
	300	}
	301	}
9c867fbe	302	strlcat(state->pp_buf, "\n", PAGE_SIZE);
1da177e4 LT	303	return 1;
	304	}
	305	#endif
	306
	307	#ifdef CONFIG_ACORN_PARTITION_ICS
	308
	309	struct ics_part {
	310	__le32 start;
	311	__le32 size;
	312	};
	313
1493bf21 TH	314	static int adfspart_check_ICSLinux(struct parsed_partitions *state,
1493bf21 TH	315	unsigned long block)
1da177e4 LT	316	{
1da177e4 LT	317	Sector sect;
1493bf21	318	unsigned char *data = read_part_sector(state, block, &sect);
1da177e4 LT	319	int result = 0;
	320
	321	if (data) {
	322	if (memcmp(data, "LinuxPart", 9) == 0)
	323	result = 1;
	324	put_dev_sector(sect);
	325	}
	326
	327	return result;
	328	}
	329
	330	/*
	331	* Check for a valid ICS partition using the checksum.
	332	*/
	333	static inline int valid_ics_sector(const unsigned char *data)
	334	{
	335	unsigned long sum;
	336	int i;
	337
	338	for (i = 0, sum = 0x50617274; i < 508; i++)
	339	sum += data[i];
	340
	341	sum -= le32_to_cpu((__le32 )(&data[508]));
	342
	343	return sum == 0;
	344	}
	345
	346	/*
	347	* Purpose: allocate ICS partitions.
	348	* Params : hd - pointer to gendisk structure to store partition info.
	349	* dev - device number to access.
	350	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
	351	* Alloc : hda = whole drive
	352	* hda1 = ADFS partition 0 on first drive.
	353	* hda2 = ADFS partition 1 on first drive.
	354	* ..etc..
	355	*/
1493bf21	356	int adfspart_check_ICS(struct parsed_partitions *state)
1da177e4 LT	357	{
	358	const unsigned char *data;
	359	const struct ics_part *p;
	360	int slot;
	361	Sector sect;
	362
	363	/*
	364	* Try ICS style partitions - sector 0 contains partition info.
	365	*/
1493bf21	366	data = read_part_sector(state, 0, &sect);
1da177e4 LT	367	if (!data)
	368	return -1;
	369
	370	if (!valid_ics_sector(data)) {
	371	put_dev_sector(sect);
	372	return 0;
	373	}
	374
9c867fbe	375	strlcat(state->pp_buf, " [ICS]", PAGE_SIZE);
1da177e4 LT	376
	377	for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
	378	u32 start = le32_to_cpu(p->start);
	379	s32 size = le32_to_cpu(p->size); /* yes, it's signed. */
	380
	381	if (slot == state->limit)
	382	break;
	383
	384	/*
	385	* Negative sizes tell the RISC OS ICS driver to ignore
	386	* this partition - in effect it says that this does not
	387	* contain an ADFS filesystem.
	388	*/
	389	if (size < 0) {
	390	size = -size;
	391
	392	/*
	393	* Our own extension - We use the first sector
	394	* of the partition to identify what type this
	395	* partition is. We must not make this visible
	396	* to the filesystem.
	397	*/
1493bf21	398	if (size > 1 && adfspart_check_ICSLinux(state, start)) {
1da177e4 LT	399	start += 1;
	400	size -= 1;
	401	}
	402	}
	403
	404	if (size)
	405	put_partition(state, slot++, start, size);
	406	}
	407
	408	put_dev_sector(sect);
9c867fbe	409	strlcat(state->pp_buf, "\n", PAGE_SIZE);
1da177e4 LT	410	return 1;
	411	}
	412	#endif
	413
	414	#ifdef CONFIG_ACORN_PARTITION_POWERTEC
	415	struct ptec_part {
	416	__le32 unused1;
	417	__le32 unused2;
	418	__le32 start;
	419	__le32 size;
	420	__le32 unused5;
	421	char type[8];
	422	};
	423
	424	static inline int valid_ptec_sector(const unsigned char *data)
	425	{
	426	unsigned char checksum = 0x2a;
	427	int i;
	428
	429	/*
	430	* If it looks like a PC/BIOS partition, then it
	431	* probably isn't PowerTec.
	432	*/
	433	if (data[510] == 0x55 && data[511] == 0xaa)
	434	return 0;
	435
	436	for (i = 0; i < 511; i++)
	437	checksum += data[i];
	438
	439	return checksum == data[511];
	440	}
	441
	442	/*
	443	* Purpose: allocate ICS partitions.
	444	* Params : hd - pointer to gendisk structure to store partition info.
	445	* dev - device number to access.
	446	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
	447	* Alloc : hda = whole drive
	448	* hda1 = ADFS partition 0 on first drive.
	449	* hda2 = ADFS partition 1 on first drive.
	450	* ..etc..
	451	*/
1493bf21	452	int adfspart_check_POWERTEC(struct parsed_partitions *state)
1da177e4 LT	453	{
	454	Sector sect;
	455	const unsigned char *data;
	456	const struct ptec_part *p;
	457	int slot = 1;
	458	int i;
	459
1493bf21	460	data = read_part_sector(state, 0, &sect);
1da177e4 LT	461	if (!data)
	462	return -1;
	463
	464	if (!valid_ptec_sector(data)) {
	465	put_dev_sector(sect);
	466	return 0;
	467	}
	468
9c867fbe	469	strlcat(state->pp_buf, " [POWERTEC]", PAGE_SIZE);
1da177e4 LT	470
	471	for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
	472	u32 start = le32_to_cpu(p->start);
	473	u32 size = le32_to_cpu(p->size);
	474
	475	if (size)
	476	put_partition(state, slot++, start, size);
	477	}
	478
	479	put_dev_sector(sect);
9c867fbe	480	strlcat(state->pp_buf, "\n", PAGE_SIZE);
1da177e4 LT	481	return 1;
	482	}
	483	#endif
	484
	485	#ifdef CONFIG_ACORN_PARTITION_EESOX
	486	struct eesox_part {
	487	char magic[6];
	488	char name[10];
	489	__le32 start;
	490	__le32 unused6;
	491	__le32 unused7;
	492	__le32 unused8;
	493	};
	494
	495	/*
	496	* Guess who created this format?
	497	*/
	498	static const char eesox_name[] = {
	499	'N', 'e', 'i', 'l', ' ',
	500	'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
	501	};
	502
	503	/*
	504	* EESOX SCSI partition format.
	505	*
	506	* This is a goddamned awful partition format. We don't seem to store
	507	* the size of the partition in this table, only the start addresses.
	508	*
	509	* There are two possibilities where the size comes from:
	510	* 1. The individual ADFS boot block entries that are placed on the disk.
	511	* 2. The start address of the next entry.
	512	*/
1493bf21	513	int adfspart_check_EESOX(struct parsed_partitions *state)
1da177e4 LT	514	{
	515	Sector sect;
	516	const unsigned char *data;
	517	unsigned char buffer[256];
	518	struct eesox_part *p;
	519	sector_t start = 0;
	520	int i, slot = 1;
	521
1493bf21	522	data = read_part_sector(state, 7, &sect);
1da177e4 LT	523	if (!data)
	524	return -1;
	525
	526	/*
	527	* "Decrypt" the partition table. God knows why...
	528	*/
	529	for (i = 0; i < 256; i++)
	530	buffer[i] = data[i] ^ eesox_name[i & 15];
	531
	532	put_dev_sector(sect);
	533
	534	for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
	535	sector_t next;
	536
	537	if (memcmp(p->magic, "Eesox", 6))
	538	break;
	539
	540	next = le32_to_cpu(p->start);
	541	if (i)
	542	put_partition(state, slot++, start, next - start);
	543	start = next;
	544	}
	545
	546	if (i != 0) {
	547	sector_t size;
	548
1493bf21	549	size = get_capacity(state->bdev->bd_disk);
1da177e4	550	put_partition(state, slot++, start, size - start);
9c867fbe	551	strlcat(state->pp_buf, "\n", PAGE_SIZE);
1da177e4 LT	552	}
	553
	554	return i ? 1 : 0;
	555	}
	556	#endif