[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)
		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, struct block_device *bdev,
		unsigned long first_sect, int slot, unsigned long nr_sects)
{
	Sector sect;
	struct riscix_record *rr;
	
	rr = (struct riscix_record *)read_dev_sector(bdev, 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, struct block_device *bdev,
		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 = (struct linux_part *)read_dev_sector(bdev, 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, struct block_device *bdev)
{
	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_dev_sector(bdev, 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, bdev, first_sector,
						 slot, nr_sects);
			break;
#endif

		case PARTITION_LINUX:
			slot = linux_partition(state, bdev, 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, struct block_device *bdev)
{
	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_dev_sector(bdev, 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);

#ifdef CONFIG_BLK_DEV_MFM
	if (MAJOR(bdev->bd_dev) == MFM_ACORN_MAJOR) {
		extern void xd_set_geometry(struct block_device *,
			unsigned char, unsigned char, unsigned int);
		xd_set_geometry(bdev, dr->secspertrack, heads, 1);
		invalidate_bh_lrus();
		truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
	}
#endif

	/*
	 * Work out start of non-adfs partition.
	 */
	nr_sects = (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, bdev, start_sect,
						 slot, nr_sects);
			break;
#endif

		case PARTITION_LINUX:
			slot = linux_partition(state, bdev, 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 block_device *bdev, unsigned long block)
{
	Sector sect;
	unsigned char *data = read_dev_sector(bdev, 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, struct block_device *bdev)
{
	const unsigned char *data;
	const struct ics_part *p;
	int slot;
	Sector sect;

	/*
	 * Try ICS style partitions - sector 0 contains partition info.
	 */
	data = read_dev_sector(bdev, 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(bdev, 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, struct block_device *bdev)
{
	Sector sect;
	const unsigned char *data;
	const struct ptec_part *p;
	int slot = 1;
	int i;

	data = read_dev_sector(bdev, 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, struct block_device *bdev)
{
	Sector sect;
	const unsigned char *data;
	unsigned char buffer[256];
	struct eesox_part *p;
	sector_t start = 0;
	int i, slot = 1;

	data = read_dev_sector(bdev, 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(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)
1da177e4 LT	73	static int
	74	riscix_partition(struct parsed_partitions state, struct block_device bdev,
	75	unsigned long first_sect, int slot, unsigned long nr_sects)
	76	{
	77	Sector sect;
	78	struct riscix_record *rr;
	79
	80	rr = (struct riscix_record *)read_dev_sector(bdev, first_sect, &sect);
	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)
1da177e4 LT	126	static int
	127	linux_partition(struct parsed_partitions state, struct block_device bdev,
	128	unsigned long first_sect, int slot, unsigned long nr_sects)
	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
	138	linuxp = (struct linux_part *)read_dev_sector(bdev, first_sect, &sect);
	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
	159	#ifdef CONFIG_ACORN_PARTITION_CUMANA
	160	int
	161	adfspart_check_CUMANA(struct parsed_partitions state, struct block_device bdev)
	162	{
	163	unsigned long first_sector = 0;
	164	unsigned int start_blk = 0;
	165	Sector sect;
	166	unsigned char *data;
	167	char *name = "CUMANA/ADFS";
	168	int first = 1;
	169	int slot = 1;
	170
	171	/*
	172	* Try Cumana style partitions - sector 6 contains ADFS boot block
	173	* with pointer to next 'drive'.
	174	*
	175	* There are unknowns in this code - is the 'cylinder number' of the
	176	* next partition relative to the start of this one - I'm assuming
	177	* it is.
	178	*
	179	* Also, which ID did Cumana use?
	180	*
	181	* This is totally unfinished, and will require more work to get it
	182	* going. Hence it is totally untested.
	183	*/
	184	do {
	185	struct adfs_discrecord *dr;
	186	unsigned int nr_sects;
	187
	188	data = read_dev_sector(bdev, start_blk * 2 + 6, &sect);
	189	if (!data)
	190	return -1;
	191
	192	if (slot == state->limit)
	193	break;
	194
	195	dr = adfs_partition(state, name, data, first_sector, slot++);
	196	if (!dr)
	197	break;
	198
	199	name = NULL;
	200
	201	nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
	202	(dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
	203	dr->secspertrack;
	204
	205	if (!nr_sects)
	206	break;
	207
	208	first = 0;
	209	first_sector += nr_sects;
	210	start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
	211	nr_sects = 0; /* hmm - should be partition size */
	212
	213	switch (data[0x1fc] & 15) {
	214	case 0: /* No partition / ADFS? */
	215	break;
	216
	217	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	218	case PARTITION_RISCIX_SCSI:
	219	/* RISCiX - we don't know how to find the next one. */
	220	slot = riscix_partition(state, bdev, first_sector,
	221	slot, nr_sects);
222	break;
223	#endif
224
225	case PARTITION_LINUX:
226	slot = linux_partition(state, bdev, first_sector,
227	slot, nr_sects);
228	break;
229	}
230	put_dev_sector(sect);
231	if (slot == -1)
232	return -1;
233	} while (1);
234	put_dev_sector(sect);
235	return first ? 0 : 1;
236	}
237	#endif
238
239	#ifdef CONFIG_ACORN_PARTITION_ADFS
240	/*
241	* Purpose: allocate ADFS partitions.
242	*
243	* Params : hd - pointer to gendisk structure to store partition info.
244	* dev - device number to access.
245	*
246	* Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
247	*
248	* Alloc : hda = whole drive
249	* hda1 = ADFS partition on first drive.
250	* hda2 = non-ADFS partition.
251	*/
252	int
253	adfspart_check_ADFS(struct parsed_partitions state, struct block_device bdev)
254	{
255	unsigned long start_sect, nr_sects, sectscyl, heads;
256	Sector sect;
257	unsigned char *data;
258	struct adfs_discrecord *dr;
259	unsigned char id;
260	int slot = 1;
261
262	data = read_dev_sector(bdev, 6, &sect);
263	if (!data)
264	return -1;
265
266	dr = adfs_partition(state, "ADFS", data, 0, slot++);
267	if (!dr) {
268	put_dev_sector(sect);
269	return 0;
270	}
271
272	heads = dr->heads + ((dr->lowsector >> 6) & 1);
273	sectscyl = dr->secspertrack * heads;
274	start_sect = ((data[0x1fe] << 8) + data[0x1fd]) * sectscyl;
275	id = data[0x1fc] & 15;
276	put_dev_sector(sect);
277
278	#ifdef CONFIG_BLK_DEV_MFM
279	if (MAJOR(bdev->bd_dev) == MFM_ACORN_MAJOR) {
280	extern void xd_set_geometry(struct block_device *,
281	unsigned char, unsigned char, unsigned int);
282	xd_set_geometry(bdev, dr->secspertrack, heads, 1);
96018fda	283	invalidate_bh_lrus();
1da177e4 LT	284	truncate_inode_pages(bdev->bd_inode->i_mapping, 0);
	285	}
	286	#endif
	287
	288	/*
	289	* Work out start of non-adfs partition.
	290	*/
	291	nr_sects = (bdev->bd_inode->i_size >> 9) - start_sect;
	292
	293	if (start_sect) {
	294	switch (id) {
	295	#ifdef CONFIG_ACORN_PARTITION_RISCIX
	296	case PARTITION_RISCIX_SCSI:
	297	case PARTITION_RISCIX_MFM:
	298	slot = riscix_partition(state, bdev, start_sect,
	299	slot, nr_sects);
	300	break;
	301	#endif
	302
	303	case PARTITION_LINUX:
	304	slot = linux_partition(state, bdev, start_sect,
	305	slot, nr_sects);
	306	break;
	307	}
	308	}
	309	printk("\n");
	310	return 1;
	311	}
	312	#endif
	313
	314	#ifdef CONFIG_ACORN_PARTITION_ICS
	315
	316	struct ics_part {
	317	__le32 start;
	318	__le32 size;
	319	};
	320
	321	static int adfspart_check_ICSLinux(struct block_device *bdev, unsigned long block)
	322	{
	323	Sector sect;
	324	unsigned char *data = read_dev_sector(bdev, block, &sect);
	325	int result = 0;
	326
	327	if (data) {
	328	if (memcmp(data, "LinuxPart", 9) == 0)
	329	result = 1;
	330	put_dev_sector(sect);
	331	}
	332
	333	return result;
	334	}
	335
	336	/*
	337	* Check for a valid ICS partition using the checksum.
	338	*/
	339	static inline int valid_ics_sector(const unsigned char *data)
	340	{
	341	unsigned long sum;
	342	int i;
	343
	344	for (i = 0, sum = 0x50617274; i < 508; i++)
	345	sum += data[i];
	346
	347	sum -= le32_to_cpu((__le32 )(&data[508]));
348
349	return sum == 0;
350	}
351
352	/*
353	* Purpose: allocate ICS partitions.
354	* Params : hd - pointer to gendisk structure to store partition info.
355	* dev - device number to access.
356	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
357	* Alloc : hda = whole drive
358	* hda1 = ADFS partition 0 on first drive.
359	* hda2 = ADFS partition 1 on first drive.
360	* ..etc..
361	*/
362	int
363	adfspart_check_ICS(struct parsed_partitions state, struct block_device bdev)
364	{
365	const unsigned char *data;
366	const struct ics_part *p;
367	int slot;
368	Sector sect;
369
370	/*
371	* Try ICS style partitions - sector 0 contains partition info.
372	*/
373	data = read_dev_sector(bdev, 0, &sect);
374	if (!data)
375	return -1;
376
377	if (!valid_ics_sector(data)) {
378	put_dev_sector(sect);
379	return 0;
380	}
381
382	printk(" [ICS]");
383
384	for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
385	u32 start = le32_to_cpu(p->start);
386	s32 size = le32_to_cpu(p->size); /* yes, it's signed. */
387
388	if (slot == state->limit)
389	break;
390
391	/*
392	* Negative sizes tell the RISC OS ICS driver to ignore
393	* this partition - in effect it says that this does not
394	* contain an ADFS filesystem.
395	*/
396	if (size < 0) {
397	size = -size;
398
399	/*
400	* Our own extension - We use the first sector
401	* of the partition to identify what type this
402	* partition is. We must not make this visible
403	* to the filesystem.
404	*/
405	if (size > 1 && adfspart_check_ICSLinux(bdev, start)) {
406	start += 1;
407	size -= 1;
408	}
409	}
410
411	if (size)
412	put_partition(state, slot++, start, size);
413	}
414
415	put_dev_sector(sect);
416	printk("\n");
417	return 1;
418	}
419	#endif
420
421	#ifdef CONFIG_ACORN_PARTITION_POWERTEC
422	struct ptec_part {
423	__le32 unused1;
424	__le32 unused2;
425	__le32 start;
426	__le32 size;
427	__le32 unused5;
428	char type[8];
429	};
430
431	static inline int valid_ptec_sector(const unsigned char *data)
432	{
433	unsigned char checksum = 0x2a;
434	int i;
435
436	/*
437	* If it looks like a PC/BIOS partition, then it
438	* probably isn't PowerTec.
439	*/
440	if (data[510] == 0x55 && data[511] == 0xaa)
441	return 0;
442
443	for (i = 0; i < 511; i++)
444	checksum += data[i];
445
446	return checksum == data[511];
447	}
448
449	/*
450	* Purpose: allocate ICS partitions.
451	* Params : hd - pointer to gendisk structure to store partition info.
452	* dev - device number to access.
453	* Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
454	* Alloc : hda = whole drive
455	* hda1 = ADFS partition 0 on first drive.
456	* hda2 = ADFS partition 1 on first drive.
457	* ..etc..
458	*/
459	int
460	adfspart_check_POWERTEC(struct parsed_partitions state, struct block_device bdev)
461	{
462	Sector sect;
463	const unsigned char *data;
464	const struct ptec_part *p;
465	int slot = 1;
466	int i;
467
468	data = read_dev_sector(bdev, 0, &sect);
469	if (!data)
470	return -1;
471
472	if (!valid_ptec_sector(data)) {
473	put_dev_sector(sect);
474	return 0;
475	}
476
477	printk(" [POWERTEC]");
478
479	for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
480	u32 start = le32_to_cpu(p->start);
481	u32 size = le32_to_cpu(p->size);
482
483	if (size)
484	put_partition(state, slot++, start, size);
485	}
486
487	put_dev_sector(sect);
488	printk("\n");
489	return 1;
490	}
491	#endif
492
493	#ifdef CONFIG_ACORN_PARTITION_EESOX
494	struct eesox_part {
495	char magic[6];
496	char name[10];
497	__le32 start;
498	__le32 unused6;
499	__le32 unused7;
500	__le32 unused8;
501	};
502
503	/*
504	* Guess who created this format?
505	*/
506	static const char eesox_name[] = {
507	'N', 'e', 'i', 'l', ' ',
508	'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
509	};
510
511	/*
512	* EESOX SCSI partition format.
513	*
514	* This is a goddamned awful partition format. We don't seem to store
515	* the size of the partition in this table, only the start addresses.
516	*
517	* There are two possibilities where the size comes from:
518	* 1. The individual ADFS boot block entries that are placed on the disk.
519	* 2. The start address of the next entry.
520	*/
521	int
522	adfspart_check_EESOX(struct parsed_partitions state, struct block_device bdev)
523	{
524	Sector sect;
525	const unsigned char *data;
526	unsigned char buffer[256];
527	struct eesox_part *p;
528	sector_t start = 0;
529	int i, slot = 1;
530
531	data = read_dev_sector(bdev, 7, &sect);
532	if (!data)
533	return -1;
534
535	/*
536	* "Decrypt" the partition table. God knows why...
537	*/
538	for (i = 0; i < 256; i++)
539	buffer[i] = data[i] ^ eesox_name[i & 15];
540
541	put_dev_sector(sect);
542
543	for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
544	sector_t next;
545
546	if (memcmp(p->magic, "Eesox", 6))
547	break;
548
549	next = le32_to_cpu(p->start);
550	if (i)
551	put_partition(state, slot++, start, next - start);
552	start = next;
553	}
554
555	if (i != 0) {
556	sector_t size;
557
558	size = get_capacity(bdev->bd_disk);
559	put_partition(state, slot++, start, size - start);
560	printk("\n");
561	}
562
563	return i ? 1 : 0;
564	}
565	#endif