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 */
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
28 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
29 defined(CONFIG_ACORN_PARTITION_ADFS)
30 static struct adfs_discrecord *
adfs_partition(struct parsed_partitions * state,char * name,char * data,unsigned long first_sector,int slot)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 }
53 #endif
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
71 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
72 defined(CONFIG_ACORN_PARTITION_ADFS)
73 static int
riscix_partition(struct parsed_partitions * state,struct block_device * bdev,unsigned long first_sect,int slot,unsigned long nr_sects)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, §);
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
113 #endif
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
124 #if defined(CONFIG_ACORN_PARTITION_CUMANA) || \
125 defined(CONFIG_ACORN_PARTITION_ADFS)
126 static int
linux_partition(struct parsed_partitions * state,struct block_device * bdev,unsigned long first_sect,int slot,unsigned long nr_sects)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, §);
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 }
157 #endif
158
159 #ifdef CONFIG_ACORN_PARTITION_CUMANA
160 int
adfspart_check_CUMANA(struct parsed_partitions * state,struct block_device * bdev)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, §);
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
adfspart_check_ADFS(struct parsed_partitions * state,struct block_device * bdev)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, §);
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 /*
279 * Work out start of non-adfs partition.
280 */
281 nr_sects = (bdev->bd_inode->i_size >> 9) - start_sect;
282
283 if (start_sect) {
284 switch (id) {
285 #ifdef CONFIG_ACORN_PARTITION_RISCIX
286 case PARTITION_RISCIX_SCSI:
287 case PARTITION_RISCIX_MFM:
288 slot = riscix_partition(state, bdev, start_sect,
289 slot, nr_sects);
290 break;
291 #endif
292
293 case PARTITION_LINUX:
294 slot = linux_partition(state, bdev, start_sect,
295 slot, nr_sects);
296 break;
297 }
298 }
299 printk("\n");
300 return 1;
301 }
302 #endif
303
304 #ifdef CONFIG_ACORN_PARTITION_ICS
305
306 struct ics_part {
307 __le32 start;
308 __le32 size;
309 };
310
adfspart_check_ICSLinux(struct block_device * bdev,unsigned long block)311 static int adfspart_check_ICSLinux(struct block_device *bdev, unsigned long block)
312 {
313 Sector sect;
314 unsigned char *data = read_dev_sector(bdev, block, §);
315 int result = 0;
316
317 if (data) {
318 if (memcmp(data, "LinuxPart", 9) == 0)
319 result = 1;
320 put_dev_sector(sect);
321 }
322
323 return result;
324 }
325
326 /*
327 * Check for a valid ICS partition using the checksum.
328 */
valid_ics_sector(const unsigned char * data)329 static inline int valid_ics_sector(const unsigned char *data)
330 {
331 unsigned long sum;
332 int i;
333
334 for (i = 0, sum = 0x50617274; i < 508; i++)
335 sum += data[i];
336
337 sum -= le32_to_cpu(*(__le32 *)(&data[508]));
338
339 return sum == 0;
340 }
341
342 /*
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.
350 * ..etc..
351 */
352 int
adfspart_check_ICS(struct parsed_partitions * state,struct block_device * bdev)353 adfspart_check_ICS(struct parsed_partitions *state, struct block_device *bdev)
354 {
355 const unsigned char *data;
356 const struct ics_part *p;
357 int slot;
358 Sector sect;
359
360 /*
361 * Try ICS style partitions - sector 0 contains partition info.
362 */
363 data = read_dev_sector(bdev, 0, §);
364 if (!data)
365 return -1;
366
367 if (!valid_ics_sector(data)) {
368 put_dev_sector(sect);
369 return 0;
370 }
371
372 printk(" [ICS]");
373
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. */
377
378 if (slot == state->limit)
379 break;
380
381 /*
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.
385 */
386 if (size < 0) {
387 size = -size;
388
389 /*
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
393 * to the filesystem.
394 */
395 if (size > 1 && adfspart_check_ICSLinux(bdev, start)) {
396 start += 1;
397 size -= 1;
398 }
399 }
400
401 if (size)
402 put_partition(state, slot++, start, size);
403 }
404
405 put_dev_sector(sect);
406 printk("\n");
407 return 1;
408 }
409 #endif
410
411 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
412 struct ptec_part {
413 __le32 unused1;
414 __le32 unused2;
415 __le32 start;
416 __le32 size;
417 __le32 unused5;
418 char type[8];
419 };
420
valid_ptec_sector(const unsigned char * data)421 static inline int valid_ptec_sector(const unsigned char *data)
422 {
423 unsigned char checksum = 0x2a;
424 int i;
425
426 /*
427 * If it looks like a PC/BIOS partition, then it
428 * probably isn't PowerTec.
429 */
430 if (data[510] == 0x55 && data[511] == 0xaa)
431 return 0;
432
433 for (i = 0; i < 511; i++)
434 checksum += data[i];
435
436 return checksum == data[511];
437 }
438
439 /*
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.
447 * ..etc..
448 */
449 int
adfspart_check_POWERTEC(struct parsed_partitions * state,struct block_device * bdev)450 adfspart_check_POWERTEC(struct parsed_partitions *state, struct block_device *bdev)
451 {
452 Sector sect;
453 const unsigned char *data;
454 const struct ptec_part *p;
455 int slot = 1;
456 int i;
457
458 data = read_dev_sector(bdev, 0, §);
459 if (!data)
460 return -1;
461
462 if (!valid_ptec_sector(data)) {
463 put_dev_sector(sect);
464 return 0;
465 }
466
467 printk(" [POWERTEC]");
468
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);
472
473 if (size)
474 put_partition(state, slot++, start, size);
475 }
476
477 put_dev_sector(sect);
478 printk("\n");
479 return 1;
480 }
481 #endif
482
483 #ifdef CONFIG_ACORN_PARTITION_EESOX
484 struct eesox_part {
485 char magic[6];
486 char name[10];
487 __le32 start;
488 __le32 unused6;
489 __le32 unused7;
490 __le32 unused8;
491 };
492
493 /*
494 * Guess who created this format?
495 */
496 static const char eesox_name[] = {
497 'N', 'e', 'i', 'l', ' ',
498 'C', 'r', 'i', 't', 'c', 'h', 'e', 'l', 'l', ' ', ' '
499 };
500
501 /*
502 * EESOX SCSI partition format.
503 *
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.
506 *
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.
510 */
511 int
adfspart_check_EESOX(struct parsed_partitions * state,struct block_device * bdev)512 adfspart_check_EESOX(struct parsed_partitions *state, struct block_device *bdev)
513 {
514 Sector sect;
515 const unsigned char *data;
516 unsigned char buffer[256];
517 struct eesox_part *p;
518 sector_t start = 0;
519 int i, slot = 1;
520
521 data = read_dev_sector(bdev, 7, §);
522 if (!data)
523 return -1;
524
525 /*
526 * "Decrypt" the partition table. God knows why...
527 */
528 for (i = 0; i < 256; i++)
529 buffer[i] = data[i] ^ eesox_name[i & 15];
530
531 put_dev_sector(sect);
532
533 for (i = 0, p = (struct eesox_part *)buffer; i < 8; i++, p++) {
534 sector_t next;
535
536 if (memcmp(p->magic, "Eesox", 6))
537 break;
538
539 next = le32_to_cpu(p->start);
540 if (i)
541 put_partition(state, slot++, start, next - start);
542 start = next;
543 }
544
545 if (i != 0) {
546 sector_t size;
547
548 size = get_capacity(bdev->bd_disk);
549 put_partition(state, slot++, start, size - start);
550 printk("\n");
551 }
552
553 return i ? 1 : 0;
554 }
555 #endif
556