2 * linux/fs/partitions/acorn.c
4 * Copyright (c) 1996-2000 Russell King.
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.
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
15 #include <linux/buffer_head.h>
16 #include <linux/adfs_fs.h>
22 * Partition types. (Oh for reusability)
24 #define PARTITION_RISCIX_MFM 1
25 #define PARTITION_RISCIX_SCSI 2
26 #define PARTITION_LINUX 9
28 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
29 defined(CONFIG_ACORN_PARTITION_ADFS)
30 static struct adfs_discrecord *
31 adfs_partition(struct parsed_partitions *state, char *name, char *data,
32 unsigned long first_sector, int slot)
34 struct adfs_discrecord *dr;
35 unsigned int nr_sects;
37 if (adfs_checkbblk(data))
40 dr = (struct adfs_discrecord *)(data + 0x1c0);
42 if (dr->disc_size == 0 && dr->disc_size_high == 0)
45 nr_sects = (le32_to_cpu(dr->disc_size_high) << 23) |
46 (le32_to_cpu(dr->disc_size) >> 9);
49 printk(" [%s]", name);
50 put_partition(state, slot, first_sector, nr_sects);
55 #ifdef CONFIG_ACORN_PARTITION_RISCIX
64 struct riscix_record {
66 #define RISCIX_MAGIC cpu_to_le32(0x4a657320)
68 struct riscix_part part[8];
71 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
72 defined(CONFIG_ACORN_PARTITION_ADFS)
74 riscix_partition(struct parsed_partitions *state, struct block_device *bdev,
75 unsigned long first_sect, int slot, unsigned long nr_sects)
78 struct riscix_record *rr;
80 rr = (struct riscix_record *)read_dev_sector(bdev, first_sect, §);
87 if (rr->magic == RISCIX_MAGIC) {
88 unsigned long size = nr_sects > 2 ? 2 : nr_sects;
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);
106 put_partition(state, slot++, first_sect, nr_sects);
109 put_dev_sector(sect);
115 #define LINUX_NATIVE_MAGIC 0xdeafa1de
116 #define LINUX_SWAP_MAGIC 0xdeafab1e
124 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
125 defined(CONFIG_ACORN_PARTITION_ADFS)
127 linux_partition(struct parsed_partitions *state, struct block_device *bdev,
128 unsigned long first_sect, int slot, unsigned long nr_sects)
131 struct linux_part *linuxp;
132 unsigned long size = nr_sects > 2 ? 2 : nr_sects;
136 put_partition(state, slot++, first_sect, size);
138 linuxp = (struct linux_part *)read_dev_sector(bdev, first_sect, §);
143 while (linuxp->magic == cpu_to_le32(LINUX_NATIVE_MAGIC) ||
144 linuxp->magic == cpu_to_le32(LINUX_SWAP_MAGIC)) {
145 if (slot == state->limit)
147 put_partition(state, slot++, first_sect +
148 le32_to_cpu(linuxp->start_sect),
149 le32_to_cpu(linuxp->nr_sects));
154 put_dev_sector(sect);
159 #ifdef CONFIG_ACORN_PARTITION_CUMANA
161 adfspart_check_CUMANA(struct parsed_partitions *state, struct block_device *bdev)
163 unsigned long first_sector = 0;
164 unsigned int start_blk = 0;
167 char *name = "CUMANA/ADFS";
172 * Try Cumana style partitions - sector 6 contains ADFS boot block
173 * with pointer to next 'drive'.
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
179 * Also, which ID did Cumana use?
181 * This is totally unfinished, and will require more work to get it
182 * going. Hence it is totally untested.
185 struct adfs_discrecord *dr;
186 unsigned int nr_sects;
188 data = read_dev_sector(bdev, start_blk * 2 + 6, §);
192 if (slot == state->limit)
195 dr = adfs_partition(state, name, data, first_sector, slot++);
201 nr_sects = (data[0x1fd] + (data[0x1fe] << 8)) *
202 (dr->heads + (dr->lowsector & 0x40 ? 1 : 0)) *
209 first_sector += nr_sects;
210 start_blk += nr_sects >> (BLOCK_SIZE_BITS - 9);
211 nr_sects = 0; /* hmm - should be partition size */
213 switch (data[0x1fc] & 15) {
214 case 0: /* No partition / ADFS? */
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,
225 case PARTITION_LINUX:
226 slot = linux_partition(state, bdev, first_sector,
230 put_dev_sector(sect);
234 put_dev_sector(sect);
235 return first ? 0 : 1;
239 #ifdef CONFIG_ACORN_PARTITION_ADFS
241 * Purpose: allocate ADFS partitions.
243 * Params : hd - pointer to gendisk structure to store partition info.
244 * dev - device number to access.
246 * Returns: -1 on error, 0 for no ADFS boot sector, 1 for ok.
248 * Alloc : hda = whole drive
249 * hda1 = ADFS partition on first drive.
250 * hda2 = non-ADFS partition.
253 adfspart_check_ADFS(struct parsed_partitions *state, struct block_device *bdev)
255 unsigned long start_sect, nr_sects, sectscyl, heads;
258 struct adfs_discrecord *dr;
262 data = read_dev_sector(bdev, 6, §);
266 dr = adfs_partition(state, "ADFS", data, 0, slot++);
268 put_dev_sector(sect);
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);
279 * Work out start of non-adfs partition.
281 nr_sects = (bdev->bd_inode->i_size >> 9) - start_sect;
285 #ifdef CONFIG_ACORN_PARTITION_RISCIX
286 case PARTITION_RISCIX_SCSI:
287 case PARTITION_RISCIX_MFM:
288 slot = riscix_partition(state, bdev, start_sect,
293 case PARTITION_LINUX:
294 slot = linux_partition(state, bdev, start_sect,
304 #ifdef CONFIG_ACORN_PARTITION_ICS
311 static int adfspart_check_ICSLinux(struct block_device *bdev, unsigned long block)
314 unsigned char *data = read_dev_sector(bdev, block, §);
318 if (memcmp(data, "LinuxPart", 9) == 0)
320 put_dev_sector(sect);
327 * Check for a valid ICS partition using the checksum.
329 static inline int valid_ics_sector(const unsigned char *data)
334 for (i = 0, sum = 0x50617274; i < 508; i++)
337 sum -= le32_to_cpu(*(__le32 *)(&data[508]));
343 * Purpose: allocate ICS partitions.
344 * Params : hd - pointer to gendisk structure to store partition info.
345 * dev - device number to access.
346 * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
347 * Alloc : hda = whole drive
348 * hda1 = ADFS partition 0 on first drive.
349 * hda2 = ADFS partition 1 on first drive.
353 adfspart_check_ICS(struct parsed_partitions *state, struct block_device *bdev)
355 const unsigned char *data;
356 const struct ics_part *p;
361 * Try ICS style partitions - sector 0 contains partition info.
363 data = read_dev_sector(bdev, 0, §);
367 if (!valid_ics_sector(data)) {
368 put_dev_sector(sect);
374 for (slot = 1, p = (const struct ics_part *)data; p->size; p++) {
375 u32 start = le32_to_cpu(p->start);
376 s32 size = le32_to_cpu(p->size); /* yes, it's signed. */
378 if (slot == state->limit)
382 * Negative sizes tell the RISC OS ICS driver to ignore
383 * this partition - in effect it says that this does not
384 * contain an ADFS filesystem.
390 * Our own extension - We use the first sector
391 * of the partition to identify what type this
392 * partition is. We must not make this visible
395 if (size > 1 && adfspart_check_ICSLinux(bdev, start)) {
402 put_partition(state, slot++, start, size);
405 put_dev_sector(sect);
411 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
421 static inline int valid_ptec_sector(const unsigned char *data)
423 unsigned char checksum = 0x2a;
427 * If it looks like a PC/BIOS partition, then it
428 * probably isn't PowerTec.
430 if (data[510] == 0x55 && data[511] == 0xaa)
433 for (i = 0; i < 511; i++)
436 return checksum == data[511];
440 * Purpose: allocate ICS partitions.
441 * Params : hd - pointer to gendisk structure to store partition info.
442 * dev - device number to access.
443 * Returns: -1 on error, 0 for no ICS table, 1 for partitions ok.
444 * Alloc : hda = whole drive
445 * hda1 = ADFS partition 0 on first drive.
446 * hda2 = ADFS partition 1 on first drive.
450 adfspart_check_POWERTEC(struct parsed_partitions *state, struct block_device *bdev)
453 const unsigned char *data;
454 const struct ptec_part *p;
458 data = read_dev_sector(bdev, 0, §);
462 if (!valid_ptec_sector(data)) {
463 put_dev_sector(sect);
467 printk(" [POWERTEC]");
469 for (i = 0, p = (const struct ptec_part *)data; i < 12; i++, p++) {
470 u32 start = le32_to_cpu(p->start);
471 u32 size = le32_to_cpu(p->size);
474 put_partition(state, slot++, start, size);
477 put_dev_sector(sect);
483 #ifdef CONFIG_ACORN_PARTITION_EESOX
494 * Guess who created this format?
496 static const char eesox_name[] = {
497 'N', 'e', 'i', 'l', ' ',
498 'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
502 * EESOX SCSI partition format.
504 * This is a goddamned awful partition format. We don't seem to store
505 * the size of the partition in this table, only the start addresses.
507 * There are two possibilities where the size comes from:
508 * 1. The individual ADFS boot block entries that are placed on the disk.
509 * 2. The start address of the next entry.
512 adfspart_check_EESOX(struct parsed_partitions *state, struct block_device *bdev)
515 const unsigned char *data;
516 unsigned char buffer[256];
517 struct eesox_part *p;
521 data = read_dev_sector(bdev, 7, §);
526 * "Decrypt" the partition table. God knows why...
528 for (i = 0; i < 256; i++)
529 buffer[i] = data[i] ^ eesox_name[i & 15];
531 put_dev_sector(sect);
533 for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
536 if (memcmp(p->magic, "Eesox", 6))
539 next = le32_to_cpu(p->start);
541 put_partition(state, slot++, start, next - start);
548 size = get_capacity(bdev->bd_disk);
549 put_partition(state, slot++, start, size - start);