1 /**
2 * ldm - Support for Windows Logical Disk Manager (Dynamic Disks)
3 *
4 * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
5 * Copyright (C) 2001 Anton Altaparmakov <aia21@cantab.net>
6 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
7 *
8 * Documentation is available at http://linux-ntfs.sf.net/ldm
9 *
10 * This program is free software; you can redistribute it and/or modify it under
11 * the terms of the GNU General Public License as published by the Free Software
12 * Foundation; either version 2 of the License, or (at your option) any later
13 * version.
14 *
15 * This program is distributed in the hope that it will be useful, but WITHOUT
16 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
17 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
18 * details.
19 *
20 * You should have received a copy of the GNU General Public License along with
21 * this program (in the main directory of the source in the file COPYING); if
22 * not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
23 * Boston, MA 02111-1307 USA
24 */
25
26 #include <linux/slab.h>
27 #include <linux/stringify.h>
28 #include <linux/pagemap.h>
29 #include "ldm.h"
30 #include "check.h"
31 #include "msdos.h"
32
33 typedef enum {
34 FALSE = 0,
35 TRUE = 1
36 } BOOL;
37
38 /**
39 * ldm_debug/info/error/crit - Output an error message
40 * @f: A printf format string containing the message
41 * @...: Variables to substitute into @f
42 *
43 * ldm_debug() writes a DEBUG level message to the syslog but only if the
44 * driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
45 */
46 #ifndef CONFIG_LDM_DEBUG
47 #define ldm_debug(...) do {} while (0)
48 #else
49 #define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __FUNCTION__, f, ##a)
50 #endif
51
52 #define ldm_crit(f, a...) _ldm_printk (KERN_CRIT, __FUNCTION__, f, ##a)
53 #define ldm_error(f, a...) _ldm_printk (KERN_ERR, __FUNCTION__, f, ##a)
54 #define ldm_info(f, a...) _ldm_printk (KERN_INFO, __FUNCTION__, f, ##a)
55
56 __attribute__ ((format (printf, 3, 4)))
_ldm_printk(const char * level,const char * function,const char * fmt,...)57 static void _ldm_printk (const char *level, const char *function,
58 const char *fmt, ...)
59 {
60 static char buf[128];
61 va_list args;
62
63 va_start (args, fmt);
64 vsnprintf (buf, sizeof (buf), fmt, args);
65 va_end (args);
66
67 printk ("%s%s(): %s\n", level, function, buf);
68 }
69
70
71 /**
72 * ldm_parse_hexbyte - Convert a ASCII hex number to a byte
73 * @src: Pointer to at least 2 characters to convert.
74 *
75 * Convert a two character ASCII hex string to a number.
76 *
77 * Return: 0-255 Success, the byte was parsed correctly
78 * -1 Error, an invalid character was supplied
79 */
ldm_parse_hexbyte(const u8 * src)80 static int ldm_parse_hexbyte (const u8 *src)
81 {
82 unsigned int x; /* For correct wrapping */
83 int h;
84
85 /* high part */
86 if ((x = src[0] - '0') <= '9'-'0') h = x;
87 else if ((x = src[0] - 'a') <= 'f'-'a') h = x+10;
88 else if ((x = src[0] - 'A') <= 'F'-'A') h = x+10;
89 else return -1;
90 h <<= 4;
91
92 /* low part */
93 if ((x = src[1] - '0') <= '9'-'0') return h | x;
94 if ((x = src[1] - 'a') <= 'f'-'a') return h | (x+10);
95 if ((x = src[1] - 'A') <= 'F'-'A') return h | (x+10);
96 return -1;
97 }
98
99 /**
100 * ldm_parse_guid - Convert GUID from ASCII to binary
101 * @src: 36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
102 * @dest: Memory block to hold binary GUID (16 bytes)
103 *
104 * N.B. The GUID need not be NULL terminated.
105 *
106 * Return: TRUE @dest contains binary GUID
107 * FALSE @dest contents are undefined
108 */
ldm_parse_guid(const u8 * src,u8 * dest)109 static BOOL ldm_parse_guid (const u8 *src, u8 *dest)
110 {
111 static const int size[] = { 4, 2, 2, 2, 6 };
112 int i, j, v;
113
114 if (src[8] != '-' || src[13] != '-' ||
115 src[18] != '-' || src[23] != '-')
116 return FALSE;
117
118 for (j = 0; j < 5; j++, src++)
119 for (i = 0; i < size[j]; i++, src+=2, *dest++ = v)
120 if ((v = ldm_parse_hexbyte (src)) < 0)
121 return FALSE;
122
123 return TRUE;
124 }
125
126
127 /**
128 * ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
129 * @data: Raw database PRIVHEAD structure loaded from the device
130 * @ph: In-memory privhead structure in which to return parsed information
131 *
132 * This parses the LDM database PRIVHEAD structure supplied in @data and
133 * sets up the in-memory privhead structure @ph with the obtained information.
134 *
135 * Return: TRUE @ph contains the PRIVHEAD data
136 * FALSE @ph contents are undefined
137 */
ldm_parse_privhead(const u8 * data,struct privhead * ph)138 static BOOL ldm_parse_privhead (const u8 *data, struct privhead *ph)
139 {
140 BUG_ON (!data);
141 BUG_ON (!ph);
142
143 if (MAGIC_PRIVHEAD != BE64 (data)) {
144 ldm_error ("Cannot find PRIVHEAD structure. LDM database is"
145 " corrupt. Aborting.");
146 return FALSE;
147 }
148
149 ph->ver_major = BE16 (data + 0x000C);
150 ph->ver_minor = BE16 (data + 0x000E);
151 ph->logical_disk_start = BE64 (data + 0x011B);
152 ph->logical_disk_size = BE64 (data + 0x0123);
153 ph->config_start = BE64 (data + 0x012B);
154 ph->config_size = BE64 (data + 0x0133);
155
156 if ((ph->ver_major != 2) || (ph->ver_minor != 11)) {
157 ldm_error ("Expected PRIVHEAD version %d.%d, got %d.%d."
158 " Aborting.", 2, 11, ph->ver_major, ph->ver_minor);
159 return FALSE;
160 }
161 if (ph->config_size != LDM_DB_SIZE) { /* 1 MiB in sectors. */
162 /* Warn the user and continue, carefully */
163 ldm_info ("Database is normally %u bytes, it claims to "
164 "be %llu bytes.", LDM_DB_SIZE,
165 (unsigned long long)ph->config_size );
166 }
167 if ((ph->logical_disk_size == 0) ||
168 (ph->logical_disk_start + ph->logical_disk_size > ph->config_start)) {
169 ldm_error ("PRIVHEAD disk size doesn't match real disk size");
170 return FALSE;
171 }
172
173 if (!ldm_parse_guid (data + 0x0030, ph->disk_id)) {
174 ldm_error ("PRIVHEAD contains an invalid GUID.");
175 return FALSE;
176 }
177
178 ldm_debug ("Parsed PRIVHEAD successfully.");
179 return TRUE;
180 }
181
182 /**
183 * ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
184 * @data: Raw database TOCBLOCK structure loaded from the device
185 * @toc: In-memory toc structure in which to return parsed information
186 *
187 * This parses the LDM Database TOCBLOCK (table of contents) structure supplied
188 * in @data and sets up the in-memory tocblock structure @toc with the obtained
189 * information.
190 *
191 * N.B. The *_start and *_size values returned in @toc are not range-checked.
192 *
193 * Return: TRUE @toc contains the TOCBLOCK data
194 * FALSE @toc contents are undefined
195 */
ldm_parse_tocblock(const u8 * data,struct tocblock * toc)196 static BOOL ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
197 {
198 BUG_ON (!data);
199 BUG_ON (!toc);
200
201 if (MAGIC_TOCBLOCK != BE64 (data)) {
202 ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
203 return FALSE;
204 }
205 strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
206 toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
207 toc->bitmap1_start = BE64 (data + 0x2E);
208 toc->bitmap1_size = BE64 (data + 0x36);
209
210 if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
211 sizeof (toc->bitmap1_name)) != 0) {
212 ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
213 TOC_BITMAP1, toc->bitmap1_name);
214 return FALSE;
215 }
216 strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
217 toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
218 toc->bitmap2_start = BE64 (data + 0x50);
219 toc->bitmap2_size = BE64 (data + 0x58);
220 if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
221 sizeof (toc->bitmap2_name)) != 0) {
222 ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
223 TOC_BITMAP2, toc->bitmap2_name);
224 return FALSE;
225 }
226 ldm_debug ("Parsed TOCBLOCK successfully.");
227 return TRUE;
228 }
229
230 /**
231 * ldm_parse_vmdb - Read the LDM Database VMDB structure
232 * @data: Raw database VMDB structure loaded from the device
233 * @vm: In-memory vmdb structure in which to return parsed information
234 *
235 * This parses the LDM Database VMDB structure supplied in @data and sets up
236 * the in-memory vmdb structure @vm with the obtained information.
237 *
238 * N.B. The *_start, *_size and *_seq values will be range-checked later.
239 *
240 * Return: TRUE @vm contains VMDB info
241 * FALSE @vm contents are undefined
242 */
ldm_parse_vmdb(const u8 * data,struct vmdb * vm)243 static BOOL ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
244 {
245 BUG_ON (!data);
246 BUG_ON (!vm);
247
248 if (MAGIC_VMDB != BE32 (data)) {
249 ldm_crit ("Cannot find the VMDB, database may be corrupt.");
250 return FALSE;
251 }
252
253 vm->ver_major = BE16 (data + 0x12);
254 vm->ver_minor = BE16 (data + 0x14);
255 if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
256 ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
257 "Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
258 return FALSE;
259 }
260
261 vm->vblk_size = BE32 (data + 0x08);
262 vm->vblk_offset = BE32 (data + 0x0C);
263 vm->last_vblk_seq = BE32 (data + 0x04);
264
265 ldm_debug ("Parsed VMDB successfully.");
266 return TRUE;
267 }
268
269 /**
270 * ldm_compare_privheads - Compare two privhead objects
271 * @ph1: First privhead
272 * @ph2: Second privhead
273 *
274 * This compares the two privhead structures @ph1 and @ph2.
275 *
276 * Return: TRUE Identical
277 * FALSE Different
278 */
ldm_compare_privheads(const struct privhead * ph1,const struct privhead * ph2)279 static BOOL ldm_compare_privheads (const struct privhead *ph1,
280 const struct privhead *ph2)
281 {
282 BUG_ON (!ph1);
283 BUG_ON (!ph2);
284
285 return ((ph1->ver_major == ph2->ver_major) &&
286 (ph1->ver_minor == ph2->ver_minor) &&
287 (ph1->logical_disk_start == ph2->logical_disk_start) &&
288 (ph1->logical_disk_size == ph2->logical_disk_size) &&
289 (ph1->config_start == ph2->config_start) &&
290 (ph1->config_size == ph2->config_size) &&
291 !memcmp (ph1->disk_id, ph2->disk_id, GUID_SIZE));
292 }
293
294 /**
295 * ldm_compare_tocblocks - Compare two tocblock objects
296 * @toc1: First toc
297 * @toc2: Second toc
298 *
299 * This compares the two tocblock structures @toc1 and @toc2.
300 *
301 * Return: TRUE Identical
302 * FALSE Different
303 */
ldm_compare_tocblocks(const struct tocblock * toc1,const struct tocblock * toc2)304 static BOOL ldm_compare_tocblocks (const struct tocblock *toc1,
305 const struct tocblock *toc2)
306 {
307 BUG_ON (!toc1);
308 BUG_ON (!toc2);
309
310 return ((toc1->bitmap1_start == toc2->bitmap1_start) &&
311 (toc1->bitmap1_size == toc2->bitmap1_size) &&
312 (toc1->bitmap2_start == toc2->bitmap2_start) &&
313 (toc1->bitmap2_size == toc2->bitmap2_size) &&
314 !strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
315 sizeof (toc1->bitmap1_name)) &&
316 !strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
317 sizeof (toc1->bitmap2_name)));
318 }
319
320 /**
321 * ldm_validate_privheads - Compare the primary privhead with its backups
322 * @bdev: Device holding the LDM Database
323 * @ph1: Memory struct to fill with ph contents
324 *
325 * Read and compare all three privheads from disk.
326 *
327 * The privheads on disk show the size and location of the main disk area and
328 * the configuration area (the database).
329 *
330 * Return: TRUE Success
331 * FALSE Error
332 */
ldm_validate_privheads(struct block_device * bdev,unsigned long first_sector,struct privhead * ph1,struct gendisk * hd,unsigned long first_minor)333 static BOOL ldm_validate_privheads (struct block_device *bdev,
334 unsigned long first_sector, struct privhead *ph1, struct gendisk *hd,
335 unsigned long first_minor)
336 {
337 static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
338 struct privhead *ph[3] = { ph1 };
339 Sector sect;
340 u8 *data;
341 BOOL result = FALSE;
342 long num_sects;
343 int i;
344
345 BUG_ON (!bdev);
346 BUG_ON (!ph1);
347
348 ph[1] = kmalloc (sizeof (*ph[1]), GFP_KERNEL);
349 ph[2] = kmalloc (sizeof (*ph[2]), GFP_KERNEL);
350 if (!ph[1] || !ph[2]) {
351 ldm_crit ("Out of memory.");
352 goto out;
353 }
354
355 /* off[1 & 2] are relative to ph[0]->config_start */
356 ph[0]->config_start = 0;
357
358 /* Read and parse privheads */
359 for (i = 0; i < 3; i++) {
360 data = read_dev_sector (bdev,
361 first_sector + ph[0]->config_start + off[i], §);
362 if (!data) {
363 ldm_crit ("Disk read failed.");
364 goto out;
365 }
366 result = ldm_parse_privhead (data, ph[i]);
367 put_dev_sector (sect);
368 if (!result) {
369 ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
370 if (i < 2)
371 goto out; /* Already logged */
372 else
373 break; /* FIXME ignore for now, 3rd PH can fail on odd-sized disks */
374 }
375 }
376
377 num_sects = hd->part[(first_minor >> hd->minor_shift)
378 << hd->minor_shift].nr_sects;
379
380 if ((ph[0]->config_start > num_sects) ||
381 ((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
382 ldm_crit ("Database extends beyond the end of the disk.");
383 goto out;
384 }
385
386 if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
387 ((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
388 > ph[0]->config_start)) {
389 ldm_crit ("Disk and database overlap.");
390 goto out;
391 }
392
393 if (!ldm_compare_privheads (ph[0], ph[1])) {
394 ldm_crit ("Primary and backup PRIVHEADs don't match.");
395 goto out;
396 }
397 /* FIXME ignore this for now
398 if (!ldm_compare_privheads (ph[0], ph[2])) {
399 ldm_crit ("Primary and backup PRIVHEADs don't match.");
400 goto out;
401 }*/
402 ldm_debug ("Validated PRIVHEADs successfully.");
403 result = TRUE;
404 out:
405 kfree (ph[1]);
406 kfree (ph[2]);
407 return result;
408 }
409
410 /**
411 * ldm_validate_tocblocks - Validate the table of contents and its backups
412 * @bdev: Device holding the LDM Database
413 * @base: Offset, into @bdev, of the database
414 * @ldb: Cache of the database structures
415 *
416 * Find and compare the four tables of contents of the LDM Database stored on
417 * @bdev and return the parsed information into @toc1.
418 *
419 * The offsets and sizes of the configs are range-checked against a privhead.
420 *
421 * Return: TRUE @toc1 contains validated TOCBLOCK info
422 * FALSE @toc1 contents are undefined
423 */
ldm_validate_tocblocks(struct block_device * bdev,unsigned long base,struct ldmdb * ldb)424 static BOOL ldm_validate_tocblocks (struct block_device *bdev,
425 unsigned long base, struct ldmdb *ldb)
426 {
427 static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
428 struct tocblock *tb[4];
429 struct privhead *ph;
430 Sector sect;
431 u8 *data;
432 BOOL result = FALSE;
433 int i;
434
435 BUG_ON (!bdev);
436 BUG_ON (!ldb);
437
438 ph = &ldb->ph;
439 tb[0] = &ldb->toc;
440 tb[1] = kmalloc (sizeof (*tb[1]), GFP_KERNEL);
441 tb[2] = kmalloc (sizeof (*tb[2]), GFP_KERNEL);
442 tb[3] = kmalloc (sizeof (*tb[3]), GFP_KERNEL);
443 if (!tb[1] || !tb[2] || !tb[3]) {
444 ldm_crit ("Out of memory.");
445 goto out;
446 }
447
448 for (i = 0; i < 4; i++) /* Read and parse all four toc's. */
449 {
450 data = read_dev_sector (bdev, base + off[i], §);
451 if (!data) {
452 ldm_crit ("Disk read failed.");
453 goto out;
454 }
455 result = ldm_parse_tocblock (data, tb[i]);
456 put_dev_sector (sect);
457 if (!result)
458 goto out; /* Already logged */
459 }
460
461 /* Range check the toc against a privhead. */
462 if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
463 ((tb[0]->bitmap2_start + tb[0]->bitmap2_size) > ph->config_size)) {
464 ldm_crit ("The bitmaps are out of range. Giving up.");
465 goto out;
466 }
467
468 if (!ldm_compare_tocblocks (tb[0], tb[1]) || /* Compare all tocs. */
469 !ldm_compare_tocblocks (tb[0], tb[2]) ||
470 !ldm_compare_tocblocks (tb[0], tb[3])) {
471 ldm_crit ("The TOCBLOCKs don't match.");
472 goto out;
473 }
474
475 ldm_debug ("Validated TOCBLOCKs successfully.");
476 result = TRUE;
477 out:
478 kfree (tb[1]);
479 kfree (tb[2]);
480 kfree (tb[3]);
481 return result;
482 }
483
484 /**
485 * ldm_validate_vmdb - Read the VMDB and validate it
486 * @bdev: Device holding the LDM Database
487 * @base: Offset, into @bdev, of the database
488 * @ldb: Cache of the database structures
489 *
490 * Find the vmdb of the LDM Database stored on @bdev and return the parsed
491 * information in @ldb.
492 *
493 * Return: TRUE @ldb contains validated VBDB info
494 * FALSE @ldb contents are undefined
495 */
ldm_validate_vmdb(struct block_device * bdev,unsigned long base,struct ldmdb * ldb)496 static BOOL ldm_validate_vmdb (struct block_device *bdev, unsigned long base,
497 struct ldmdb *ldb)
498 {
499 Sector sect;
500 u8 *data;
501 BOOL result = FALSE;
502 struct vmdb *vm;
503 struct tocblock *toc;
504
505 BUG_ON (!bdev);
506 BUG_ON (!ldb);
507
508 vm = &ldb->vm;
509 toc = &ldb->toc;
510
511 data = read_dev_sector (bdev, base + OFF_VMDB, §);
512 if (!data) {
513 ldm_crit ("Disk read failed.");
514 return FALSE;
515 }
516
517 if (!ldm_parse_vmdb (data, vm))
518 goto out; /* Already logged */
519
520 /* Are there uncommitted transactions? */
521 if (BE16(data + 0x10) != 0x01) {
522 ldm_crit ("Database is not in a consistant state. Aborting.");
523 goto out;
524 }
525
526 if (vm->vblk_offset != 512)
527 ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
528
529 /* FIXME: How should we handle this situation? */
530 if ((vm->vblk_size * vm->last_vblk_seq) != (toc->bitmap1_size << 9))
531 ldm_info ("VMDB and TOCBLOCK don't agree on the database size.");
532
533 result = TRUE;
534 out:
535 put_dev_sector (sect);
536 return result;
537 }
538
539
540 /**
541 * ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
542 * @bdev: Device holding the LDM Database
543 *
544 * This function provides a weak test to decide whether the device is a dynamic
545 * disk or not. It looks for an MS-DOS-style partition table containing at
546 * least one partition of type 0x42 (formerly SFS, now used by Windows for
547 * dynamic disks).
548 *
549 * N.B. The only possible error can come from the read_dev_sector and that is
550 * only likely to happen if the underlying device is strange. If that IS
551 * the case we should return zero to let someone else try.
552 *
553 * Return: TRUE @bdev is a dynamic disk
554 * FALSE @bdev is not a dynamic disk, or an error occurred
555 */
ldm_validate_partition_table(struct block_device * bdev)556 static BOOL ldm_validate_partition_table (struct block_device *bdev)
557 {
558 Sector sect;
559 u8 *data;
560 struct partition *p;
561 int i;
562 BOOL result = FALSE;
563
564 BUG_ON (!bdev);
565
566 data = read_dev_sector (bdev, 0, §);
567 if (!data) {
568 ldm_crit ("Disk read failed.");
569 return FALSE;
570 }
571
572 if (*(u16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC)) {
573 ldm_debug ("No MS-DOS partition table found.");
574 goto out;
575 }
576
577 p = (struct partition*)(data + 0x01BE);
578 for (i = 0; i < 4; i++, p++)
579 if (SYS_IND (p) == WIN2K_DYNAMIC_PARTITION) {
580 result = TRUE;
581 break;
582 }
583
584 if (result)
585 ldm_debug ("Parsed partition table successfully.");
586 else
587 ldm_debug ("Found an MS-DOS partition table, not a dynamic disk.");
588 out:
589 put_dev_sector (sect);
590 return result;
591 }
592
593 /**
594 * ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
595 * @ldb: Cache of the database structures
596 *
597 * The LDM Database contains a list of all partitions on all dynamic disks. The
598 * primary PRIVHEAD, at the beginning of the physical disk, tells us the GUID of
599 * this disk. This function searches for the GUID in a linked list of vblk's.
600 *
601 * Return: Pointer, A matching vblk was found
602 * NULL, No match, or an error
603 */
ldm_get_disk_objid(const struct ldmdb * ldb)604 static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
605 {
606 struct list_head *item;
607
608 BUG_ON (!ldb);
609
610 list_for_each (item, &ldb->v_disk) {
611 struct vblk *v = list_entry (item, struct vblk, list);
612 if (!memcmp (v->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
613 return v;
614 }
615
616 return NULL;
617 }
618
619 /**
620 * ldm_create_partition - Create a kernel partition device
621 * @hd: gendisk structure in which to create partition
622 * @minor: Create a this minor number on the device
623 * @start: Offset (in sectors) into the device of the partition
624 * @size: Size (in sectors) of the partition
625 *
626 * This validates the range, then puts an entry into the kernel's partition
627 * table.
628 *
629 * Return: TRUE Created the partition
630 * FALSE Error
631 */
ldm_create_partition(struct gendisk * hd,int minor,int start,int size)632 static BOOL ldm_create_partition (struct gendisk *hd, int minor, int start,
633 int size)
634 {
635 int disk_minor;
636
637 BUG_ON (!hd);;
638 BUG_ON (!hd->part);
639
640 /* Get the minor number of the parent device
641 * so we can check we don't go beyond the end of the device. */
642 disk_minor = (minor >> hd->minor_shift) << hd->minor_shift;
643 if ((start < 1) || ((start + size) > hd->part[disk_minor].nr_sects)) {
644 ldm_crit ("Partition exceeds physical disk. Aborting.");
645 return FALSE;
646 }
647 add_gd_partition (hd, minor, start, size);
648 ldm_debug ("Created partition successfully.");
649 return TRUE;
650 }
651
652 /**
653 * ldm_create_data_partitions - Create data partitions for this device
654 * @pp: List of the partitions parsed so far
655 * @ldb: Cache of the database structures
656 *
657 * The database contains ALL the partitions for ALL disk groups, so we need to
658 * filter out this specific disk. Using the disk's object id, we can find all
659 * the partitions in the database that belong to this disk.
660 *
661 * Add each partition in our database, to the parsed_partitions structure.
662 *
663 * N.B. This function creates the partitions in the order it finds partition
664 * objects in the linked list.
665 *
666 * Return: TRUE Partition created
667 * FALSE Error, probably a range checking problem
668 */
ldm_create_data_partitions(struct gendisk * hd,unsigned long first_sector,int first_minor,const struct ldmdb * ldb)669 static BOOL ldm_create_data_partitions (struct gendisk *hd,
670 unsigned long first_sector, int first_minor, const struct ldmdb *ldb)
671 {
672 struct list_head *item;
673 struct vblk_part *part;
674 struct vblk *disk;
675 int disk_minor;
676 int minor;
677
678 BUG_ON (!hd);
679 BUG_ON (!ldb);
680
681 disk = ldm_get_disk_objid (ldb);
682 if (!disk) {
683 ldm_crit ("Can't find the ID of this disk in the database.");
684 return FALSE;
685 }
686
687 /* We use the range-check the partitions against the parent device. */
688 disk_minor = (first_minor >> hd->minor_shift) << hd->minor_shift;
689 minor = first_minor;
690
691 printk (" [LDM]");
692
693 /* Create the data partitions */
694 list_for_each (item, &ldb->v_part) {
695 struct vblk *vb;
696 vb = list_entry (item, struct vblk, list);
697 part = &vb->vblk.part;
698
699 if (part->disk_id != disk->obj_id)
700 continue;
701
702 if (!ldm_create_partition (hd, minor,
703 part->start + ldb->ph.logical_disk_start, part->size))
704 continue; /* Already logged */
705 minor++;
706 }
707
708 printk ("\n");
709 return TRUE;
710 }
711
712
713 /**
714 * ldm_relative - Calculate the next relative offset
715 * @buffer: Block of data being worked on
716 * @buflen: Size of the block of data
717 * @base: Size of the previous fixed width fields
718 * @offset: Cumulative size of the previous variable-width fields
719 *
720 * Because many of the VBLK fields are variable-width, it's necessary
721 * to calculate each offset based on the previous one and the length
722 * of the field it pointed to.
723 *
724 * Return: -1 Error, the calculated offset exceeded the size of the buffer
725 * n OK, a range-checked offset into buffer
726 */
ldm_relative(const u8 * buffer,int buflen,int base,int offset)727 static int ldm_relative (const u8 *buffer, int buflen, int base, int offset)
728 {
729
730 base += offset;
731 if ((!buffer) || (offset < 0) || (base > buflen))
732 return -1;
733 if ((base + buffer[base]) >= buflen)
734 return -1;
735
736 return buffer[base] + offset + 1;
737 }
738
739 /**
740 * ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
741 * @block: Pointer to the variable-width number to convert
742 *
743 * Large numbers in the LDM Database are often stored in a packed format. Each
744 * number is prefixed by a one byte width marker. All numbers in the database
745 * are stored in big-endian byte order. This function reads one of these
746 * numbers and returns the result
747 *
748 * N.B. This function DOES NOT perform any range checking, though the most
749 * it will read is eight bytes.
750 *
751 * Return: n A number
752 * 0 Zero, or an error occurred
753 */
ldm_get_vnum(const u8 * block)754 static u64 ldm_get_vnum (const u8 *block)
755 {
756 u64 tmp = 0;
757 u8 length;
758
759 BUG_ON (!block);
760
761 length = *block++;
762
763 if (length && length <= 8)
764 while (length--)
765 tmp = (tmp << 8) | *block++;
766 else
767 ldm_error ("Illegal length %d.", length);
768
769 return tmp;
770 }
771
772 /**
773 * ldm_get_vstr - Read a length-prefixed string into a buffer
774 * @block: Pointer to the length marker
775 * @buffer: Location to copy string to
776 * @buflen: Size of the output buffer
777 *
778 * Many of the strings in the LDM Database are not NULL terminated. Instead
779 * they are prefixed by a one byte length marker. This function copies one of
780 * these strings into a buffer.
781 *
782 * N.B. This function DOES NOT perform any range checking on the input.
783 * If the buffer is too small, the output will be truncated.
784 *
785 * Return: 0, Error and @buffer contents are undefined
786 * n, String length in characters (excluding NULL)
787 * buflen-1, String was truncated.
788 */
ldm_get_vstr(const u8 * block,u8 * buffer,int buflen)789 static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
790 {
791 int length;
792
793 BUG_ON (!block);
794 BUG_ON (!buffer);
795
796 length = block[0];
797 if (length >= buflen) {
798 ldm_error ("Truncating string %d -> %d.", length, buflen);
799 length = buflen - 1;
800 }
801 memcpy (buffer, block + 1, length);
802 buffer[length] = 0;
803 return length;
804 }
805
806
807 /**
808 * ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
809 * @buffer: Block of data being worked on
810 * @buflen: Size of the block of data
811 * @vb: In-memory vblk in which to return information
812 *
813 * Read a raw VBLK Component object (version 3) into a vblk structure.
814 *
815 * Return: TRUE @vb contains a Component VBLK
816 * FALSE @vb contents are not defined
817 */
ldm_parse_cmp3(const u8 * buffer,int buflen,struct vblk * vb)818 static BOOL ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
819 {
820 int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
821 struct vblk_comp *comp;
822
823 BUG_ON (!buffer);
824 BUG_ON (!vb);
825
826 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
827 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
828 r_vstate = ldm_relative (buffer, buflen, 0x18, r_name);
829 r_child = ldm_relative (buffer, buflen, 0x1D, r_vstate);
830 r_parent = ldm_relative (buffer, buflen, 0x2D, r_child);
831
832 if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
833 r_stripe = ldm_relative (buffer, buflen, 0x2E, r_parent);
834 r_cols = ldm_relative (buffer, buflen, 0x2E, r_stripe);
835 len = r_cols;
836 } else {
837 r_stripe = 0;
838 r_cols = 0;
839 len = r_parent;
840 }
841 if (len < 0)
842 return FALSE;
843
844 len += VBLK_SIZE_CMP3;
845 if (len != BE32 (buffer + 0x14))
846 return FALSE;
847
848 comp = &vb->vblk.comp;
849 ldm_get_vstr (buffer + 0x18 + r_name, comp->state,
850 sizeof (comp->state));
851 comp->type = buffer[0x18 + r_vstate];
852 comp->children = ldm_get_vnum (buffer + 0x1D + r_vstate);
853 comp->parent_id = ldm_get_vnum (buffer + 0x2D + r_child);
854 comp->chunksize = r_stripe ? ldm_get_vnum (buffer+r_parent+0x2E) : 0;
855
856 return TRUE;
857 }
858
859 /**
860 * ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
861 * @buffer: Block of data being worked on
862 * @buflen: Size of the block of data
863 * @vb: In-memory vblk in which to return information
864 *
865 * Read a raw VBLK Disk Group object (version 3) into a vblk structure.
866 *
867 * Return: TRUE @vb contains a Disk Group VBLK
868 * FALSE @vb contents are not defined
869 */
ldm_parse_dgr3(const u8 * buffer,int buflen,struct vblk * vb)870 static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
871 {
872 int r_objid, r_name, r_diskid, r_id1, r_id2, len;
873 struct vblk_dgrp *dgrp;
874
875 BUG_ON (!buffer);
876 BUG_ON (!vb);
877
878 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
879 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
880 r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
881
882 if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
883 r_id1 = ldm_relative (buffer, buflen, 0x24, r_diskid);
884 r_id2 = ldm_relative (buffer, buflen, 0x24, r_id1);
885 len = r_id2;
886 } else {
887 r_id1 = 0;
888 r_id2 = 0;
889 len = r_diskid;
890 }
891 if (len < 0)
892 return FALSE;
893
894 len += VBLK_SIZE_DGR3;
895 if (len != BE32 (buffer + 0x14))
896 return FALSE;
897
898 dgrp = &vb->vblk.dgrp;
899 ldm_get_vstr (buffer + 0x18 + r_name, dgrp->disk_id,
900 sizeof (dgrp->disk_id));
901 return TRUE;
902 }
903
904 /**
905 * ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
906 * @buffer: Block of data being worked on
907 * @buflen: Size of the block of data
908 * @vb: In-memory vblk in which to return information
909 *
910 * Read a raw VBLK Disk Group object (version 4) into a vblk structure.
911 *
912 * Return: TRUE @vb contains a Disk Group VBLK
913 * FALSE @vb contents are not defined
914 */
ldm_parse_dgr4(const u8 * buffer,int buflen,struct vblk * vb)915 static BOOL ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
916 {
917 char buf[64];
918 int r_objid, r_name, r_id1, r_id2, len;
919 struct vblk_dgrp *dgrp;
920
921 BUG_ON (!buffer);
922 BUG_ON (!vb);
923
924 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
925 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
926
927 if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
928 r_id1 = ldm_relative (buffer, buflen, 0x44, r_name);
929 r_id2 = ldm_relative (buffer, buflen, 0x44, r_id1);
930 len = r_id2;
931 } else {
932 r_id1 = 0;
933 r_id2 = 0;
934 len = r_name;
935 }
936 if (len < 0)
937 return FALSE;
938
939 len += VBLK_SIZE_DGR4;
940 if (len != BE32 (buffer + 0x14))
941 return FALSE;
942
943 dgrp = &vb->vblk.dgrp;
944
945 ldm_get_vstr (buffer + 0x18 + r_objid, buf, sizeof (buf));
946 return TRUE;
947 }
948
949 /**
950 * ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
951 * @buffer: Block of data being worked on
952 * @buflen: Size of the block of data
953 * @vb: In-memory vblk in which to return information
954 *
955 * Read a raw VBLK Disk object (version 3) into a vblk structure.
956 *
957 * Return: TRUE @vb contains a Disk VBLK
958 * FALSE @vb contents are not defined
959 */
ldm_parse_dsk3(const u8 * buffer,int buflen,struct vblk * vb)960 static BOOL ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
961 {
962 int r_objid, r_name, r_diskid, r_altname, len;
963 struct vblk_disk *disk;
964
965 BUG_ON (!buffer);
966 BUG_ON (!vb);
967
968 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
969 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
970 r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
971 r_altname = ldm_relative (buffer, buflen, 0x18, r_diskid);
972 len = r_altname;
973 if (len < 0)
974 return FALSE;
975
976 len += VBLK_SIZE_DSK3;
977 if (len != BE32 (buffer + 0x14))
978 return FALSE;
979
980 disk = &vb->vblk.disk;
981 ldm_get_vstr (buffer + 0x18 + r_diskid, disk->alt_name,
982 sizeof (disk->alt_name));
983 if (!ldm_parse_guid (buffer + 0x19 + r_name, disk->disk_id))
984 return FALSE;
985
986 return TRUE;
987 }
988
989 /**
990 * ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
991 * @buffer: Block of data being worked on
992 * @buflen: Size of the block of data
993 * @vb: In-memory vblk in which to return information
994 *
995 * Read a raw VBLK Disk object (version 4) into a vblk structure.
996 *
997 * Return: TRUE @vb contains a Disk VBLK
998 * FALSE @vb contents are not defined
999 */
ldm_parse_dsk4(const u8 * buffer,int buflen,struct vblk * vb)1000 static BOOL ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
1001 {
1002 int r_objid, r_name, len;
1003 struct vblk_disk *disk;
1004
1005 BUG_ON (!buffer);
1006 BUG_ON (!vb);
1007
1008 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
1009 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
1010 len = r_name;
1011 if (len < 0)
1012 return FALSE;
1013
1014 len += VBLK_SIZE_DSK4;
1015 if (len != BE32 (buffer + 0x14))
1016 return FALSE;
1017
1018 disk = &vb->vblk.disk;
1019 memcpy (disk->disk_id, buffer + 0x18 + r_name, GUID_SIZE);
1020 return TRUE;
1021 }
1022
1023 /**
1024 * ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
1025 * @buffer: Block of data being worked on
1026 * @buflen: Size of the block of data
1027 * @vb: In-memory vblk in which to return information
1028 *
1029 * Read a raw VBLK Partition object (version 3) into a vblk structure.
1030 *
1031 * Return: TRUE @vb contains a Partition VBLK
1032 * FALSE @vb contents are not defined
1033 */
ldm_parse_prt3(const u8 * buffer,int buflen,struct vblk * vb)1034 static BOOL ldm_parse_prt3 (const u8 *buffer, int buflen, struct vblk *vb)
1035 {
1036 int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
1037 struct vblk_part *part;
1038
1039 BUG_ON (!buffer);
1040 BUG_ON (!vb);
1041
1042 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
1043 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
1044 r_size = ldm_relative (buffer, buflen, 0x34, r_name);
1045 r_parent = ldm_relative (buffer, buflen, 0x34, r_size);
1046 r_diskid = ldm_relative (buffer, buflen, 0x34, r_parent);
1047
1048 if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
1049 r_index = ldm_relative (buffer, buflen, 0x34, r_diskid);
1050 len = r_index;
1051 } else {
1052 r_index = 0;
1053 len = r_diskid;
1054 }
1055 if (len < 0)
1056 return FALSE;
1057
1058 len += VBLK_SIZE_PRT3;
1059 if (len != BE32 (buffer + 0x14))
1060 return FALSE;
1061
1062 part = &vb->vblk.part;
1063 part->start = BE64 (buffer + 0x24 + r_name);
1064 part->volume_offset = BE64 (buffer + 0x2C + r_name);
1065 part->size = ldm_get_vnum (buffer + 0x34 + r_name);
1066 part->parent_id = ldm_get_vnum (buffer + 0x34 + r_size);
1067 part->disk_id = ldm_get_vnum (buffer + 0x34 + r_parent);
1068 if (vb->flags & VBLK_FLAG_PART_INDEX)
1069 part->partnum = buffer[0x35 + r_diskid];
1070 else
1071 part->partnum = 0;
1072
1073 return TRUE;
1074 }
1075
1076 /**
1077 * ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
1078 * @buffer: Block of data being worked on
1079 * @buflen: Size of the block of data
1080 * @vb: In-memory vblk in which to return information
1081 *
1082 * Read a raw VBLK Volume object (version 5) into a vblk structure.
1083 *
1084 * Return: TRUE @vb contains a Volume VBLK
1085 * FALSE @vb contents are not defined
1086 */
ldm_parse_vol5(const u8 * buffer,int buflen,struct vblk * vb)1087 static BOOL ldm_parse_vol5 (const u8 *buffer, int buflen, struct vblk *vb)
1088 {
1089 int r_objid, r_name, r_vtype, r_child, r_size, r_id1, r_id2, r_size2;
1090 int r_drive, len;
1091 struct vblk_volu *volu;
1092
1093 BUG_ON (!buffer);
1094 BUG_ON (!vb);
1095
1096 r_objid = ldm_relative (buffer, buflen, 0x18, 0);
1097 r_name = ldm_relative (buffer, buflen, 0x18, r_objid);
1098 r_vtype = ldm_relative (buffer, buflen, 0x18, r_name);
1099 r_child = ldm_relative (buffer, buflen, 0x2E, r_vtype);
1100 r_size = ldm_relative (buffer, buflen, 0x3E, r_child);
1101
1102 if (buffer[0x12] & VBLK_FLAG_VOLU_ID1)
1103 r_id1 = ldm_relative (buffer, buflen, 0x53, r_size);
1104 else
1105 r_id1 = r_size;
1106
1107 if (buffer[0x12] & VBLK_FLAG_VOLU_ID2)
1108 r_id2 = ldm_relative (buffer, buflen, 0x53, r_id1);
1109 else
1110 r_id2 = r_id1;
1111
1112 if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE)
1113 r_size2 = ldm_relative (buffer, buflen, 0x53, r_id2);
1114 else
1115 r_size2 = r_id2;
1116
1117 if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE)
1118 r_drive = ldm_relative (buffer, buflen, 0x53, r_size2);
1119 else
1120 r_drive = r_size2;
1121
1122 len = r_drive;
1123 if (len < 0)
1124 return FALSE;
1125
1126 len += VBLK_SIZE_VOL5;
1127 if (len != BE32 (buffer + 0x14))
1128 return FALSE;
1129
1130 volu = &vb->vblk.volu;
1131
1132 ldm_get_vstr (buffer + 0x18 + r_name, volu->volume_type,
1133 sizeof (volu->volume_type));
1134 memcpy (volu->volume_state, buffer + 0x19 + r_vtype,
1135 sizeof (volu->volume_state));
1136 volu->size = ldm_get_vnum (buffer + 0x3E + r_child);
1137 volu->partition_type = buffer[0x42 + r_size];
1138 memcpy (volu->guid, buffer + 0x43 + r_size, sizeof (volu->guid));
1139 if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1140 ldm_get_vstr (buffer + 0x53 + r_size, volu->drive_hint,
1141 sizeof (volu->drive_hint));
1142 }
1143 return TRUE;
1144 }
1145
1146 /**
1147 * ldm_parse_vblk - Read a raw VBLK object into a vblk structure
1148 * @buf: Block of data being worked on
1149 * @len: Size of the block of data
1150 * @vb: In-memory vblk in which to return information
1151 *
1152 * Read a raw VBLK object into a vblk structure. This function just reads the
1153 * information common to all VBLK types, then delegates the rest of the work to
1154 * helper functions: ldm_parse_*.
1155 *
1156 * Return: TRUE @vb contains a VBLK
1157 * FALSE @vb contents are not defined
1158 */
ldm_parse_vblk(const u8 * buf,int len,struct vblk * vb)1159 static BOOL ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
1160 {
1161 BOOL result = FALSE;
1162 int r_objid;
1163
1164 BUG_ON (!buf);
1165 BUG_ON (!vb);
1166
1167 r_objid = ldm_relative (buf, len, 0x18, 0);
1168 if (r_objid < 0) {
1169 ldm_error ("VBLK header is corrupt.");
1170 return FALSE;
1171 }
1172
1173 vb->flags = buf[0x12];
1174 vb->type = buf[0x13];
1175 vb->obj_id = ldm_get_vnum (buf + 0x18);
1176 ldm_get_vstr (buf+0x18+r_objid, vb->name, sizeof (vb->name));
1177
1178 switch (vb->type) {
1179 case VBLK_CMP3: result = ldm_parse_cmp3 (buf, len, vb); break;
1180 case VBLK_DSK3: result = ldm_parse_dsk3 (buf, len, vb); break;
1181 case VBLK_DSK4: result = ldm_parse_dsk4 (buf, len, vb); break;
1182 case VBLK_DGR3: result = ldm_parse_dgr3 (buf, len, vb); break;
1183 case VBLK_DGR4: result = ldm_parse_dgr4 (buf, len, vb); break;
1184 case VBLK_PRT3: result = ldm_parse_prt3 (buf, len, vb); break;
1185 case VBLK_VOL5: result = ldm_parse_vol5 (buf, len, vb); break;
1186 }
1187
1188 if (result)
1189 ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
1190 (unsigned long long) vb->obj_id, vb->type);
1191 else
1192 ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
1193 (unsigned long long) vb->obj_id, vb->type);
1194
1195 return result;
1196 }
1197
1198
1199 /**
1200 * ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
1201 * @data: Raw VBLK to add to the database
1202 * @len: Size of the raw VBLK
1203 * @ldb: Cache of the database structures
1204 *
1205 * The VBLKs are sorted into categories. Partitions are also sorted by offset.
1206 *
1207 * N.B. This function does not check the validity of the VBLKs.
1208 *
1209 * Return: TRUE The VBLK was added
1210 * FALSE An error occurred
1211 */
ldm_ldmdb_add(u8 * data,int len,struct ldmdb * ldb)1212 static BOOL ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
1213 {
1214 struct vblk *vb;
1215 struct list_head *item;
1216
1217 BUG_ON (!data);
1218 BUG_ON (!ldb);
1219
1220 vb = kmalloc (sizeof (*vb), GFP_KERNEL);
1221 if (!vb) {
1222 ldm_crit ("Out of memory.");
1223 return FALSE;
1224 }
1225
1226 if (!ldm_parse_vblk (data, len, vb)) {
1227 kfree(vb);
1228 return FALSE; /* Already logged */
1229 }
1230
1231 /* Put vblk into the correct list. */
1232 switch (vb->type) {
1233 case VBLK_DGR3:
1234 case VBLK_DGR4:
1235 list_add (&vb->list, &ldb->v_dgrp);
1236 break;
1237 case VBLK_DSK3:
1238 case VBLK_DSK4:
1239 list_add (&vb->list, &ldb->v_disk);
1240 break;
1241 case VBLK_VOL5:
1242 list_add (&vb->list, &ldb->v_volu);
1243 break;
1244 case VBLK_CMP3:
1245 list_add (&vb->list, &ldb->v_comp);
1246 break;
1247 case VBLK_PRT3:
1248 /* Sort by the partition's start sector. */
1249 list_for_each (item, &ldb->v_part) {
1250 struct vblk *v = list_entry (item, struct vblk, list);
1251 if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
1252 (v->vblk.part.start > vb->vblk.part.start)) {
1253 list_add_tail (&vb->list, &v->list);
1254 return TRUE;
1255 }
1256 }
1257 list_add_tail (&vb->list, &ldb->v_part);
1258 break;
1259 }
1260 return TRUE;
1261 }
1262
1263 /**
1264 * ldm_frag_add - Add a VBLK fragment to a list
1265 * @data: Raw fragment to be added to the list
1266 * @size: Size of the raw fragment
1267 * @frags: Linked list of VBLK fragments
1268 *
1269 * Fragmented VBLKs may not be consecutive in the database, so they are placed
1270 * in a list so they can be pieced together later.
1271 *
1272 * Return: TRUE Success, the VBLK was added to the list
1273 * FALSE Error, a problem occurred
1274 */
ldm_frag_add(const u8 * data,int size,struct list_head * frags)1275 static BOOL ldm_frag_add (const u8 *data, int size, struct list_head *frags)
1276 {
1277 struct frag *f;
1278 struct list_head *item;
1279 int rec, num, group;
1280
1281 BUG_ON (!data);
1282 BUG_ON (!frags);
1283
1284 group = BE32 (data + 0x08);
1285 rec = BE16 (data + 0x0C);
1286 num = BE16 (data + 0x0E);
1287 if ((num < 1) || (num > 4)) {
1288 ldm_error ("A VBLK claims to have %d parts.", num);
1289 return FALSE;
1290 }
1291
1292 list_for_each (item, frags) {
1293 f = list_entry (item, struct frag, list);
1294 if (f->group == group)
1295 goto found;
1296 }
1297
1298 f = kmalloc (sizeof (*f) + size*num, GFP_KERNEL);
1299 if (!f) {
1300 ldm_crit ("Out of memory.");
1301 return FALSE;
1302 }
1303
1304 f->group = group;
1305 f->num = num;
1306 f->rec = rec;
1307 f->map = 0xFF << num;
1308
1309 list_add_tail (&f->list, frags);
1310 found:
1311 if (f->map & (1 << rec)) {
1312 ldm_error ("Duplicate VBLK, part %d.", rec);
1313 f->map &= 0x7F; /* Mark the group as broken */
1314 return FALSE;
1315 }
1316
1317 f->map |= (1 << rec);
1318
1319 if (num > 0) {
1320 data += VBLK_SIZE_HEAD;
1321 size -= VBLK_SIZE_HEAD;
1322 }
1323 memcpy (f->data+rec*(size-VBLK_SIZE_HEAD)+VBLK_SIZE_HEAD, data, size);
1324
1325 return TRUE;
1326 }
1327
1328 /**
1329 * ldm_frag_free - Free a linked list of VBLK fragments
1330 * @list: Linked list of fragments
1331 *
1332 * Free a linked list of VBLK fragments
1333 *
1334 * Return: none
1335 */
ldm_frag_free(struct list_head * list)1336 static void ldm_frag_free (struct list_head *list)
1337 {
1338 struct list_head *item, *tmp;
1339
1340 BUG_ON (!list);
1341
1342 list_for_each_safe (item, tmp, list)
1343 kfree (list_entry (item, struct frag, list));
1344 }
1345
1346 /**
1347 * ldm_frag_commit - Validate fragmented VBLKs and add them to the database
1348 * @frags: Linked list of VBLK fragments
1349 * @ldb: Cache of the database structures
1350 *
1351 * Now that all the fragmented VBLKs have been collected, they must be added to
1352 * the database for later use.
1353 *
1354 * Return: TRUE All the fragments we added successfully
1355 * FALSE One or more of the fragments we invalid
1356 */
ldm_frag_commit(struct list_head * frags,struct ldmdb * ldb)1357 static BOOL ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
1358 {
1359 struct frag *f;
1360 struct list_head *item;
1361
1362 BUG_ON (!frags);
1363 BUG_ON (!ldb);
1364
1365 list_for_each (item, frags) {
1366 f = list_entry (item, struct frag, list);
1367
1368 if (f->map != 0xFF) {
1369 ldm_error ("VBLK group %d is incomplete (0x%02x).",
1370 f->group, f->map);
1371 return FALSE;
1372 }
1373
1374 if (!ldm_ldmdb_add (f->data, f->num*ldb->vm.vblk_size, ldb))
1375 return FALSE; /* Already logged */
1376 }
1377 return TRUE;
1378 }
1379
1380 /**
1381 * ldm_get_vblks - Read the on-disk database of VBLKs into memory
1382 * @bdev: Device holding the LDM Database
1383 * @base: Offset, into @bdev, of the database
1384 * @ldb: Cache of the database structures
1385 *
1386 * To use the information from the VBLKs, they need to be read from the disk,
1387 * unpacked and validated. We cache them in @ldb according to their type.
1388 *
1389 * Return: TRUE All the VBLKs were read successfully
1390 * FALSE An error occurred
1391 */
ldm_get_vblks(struct block_device * bdev,unsigned long base,struct ldmdb * ldb)1392 static BOOL ldm_get_vblks (struct block_device *bdev, unsigned long base,
1393 struct ldmdb *ldb)
1394 {
1395 int size, perbuf, skip, finish, s, v, recs;
1396 u8 *data = NULL;
1397 Sector sect;
1398 BOOL result = FALSE;
1399 LIST_HEAD (frags);
1400
1401 BUG_ON (!bdev);
1402 BUG_ON (!ldb);
1403
1404 size = ldb->vm.vblk_size;
1405 perbuf = 512 / size;
1406 skip = ldb->vm.vblk_offset >> 9; /* Bytes to sectors */
1407 finish = (size * ldb->vm.last_vblk_seq) >> 9;
1408
1409 for (s = skip; s < finish; s++) { /* For each sector */
1410 data = read_dev_sector (bdev, base + OFF_VMDB + s, §);
1411 if (!data) {
1412 ldm_crit ("Disk read failed.");
1413 goto out;
1414 }
1415
1416 for (v = 0; v < perbuf; v++, data+=size) { /* For each vblk */
1417 if (MAGIC_VBLK != BE32 (data)) {
1418 ldm_error ("Expected to find a VBLK.");
1419 goto out;
1420 }
1421
1422 recs = BE16 (data + 0x0E); /* Number of records */
1423 if (recs == 1) {
1424 if (!ldm_ldmdb_add (data, size, ldb))
1425 goto out; /* Already logged */
1426 } else if (recs > 1) {
1427 if (!ldm_frag_add (data, size, &frags))
1428 goto out; /* Already logged */
1429 }
1430 /* else Record is not in use, ignore it. */
1431 }
1432 put_dev_sector (sect);
1433 data = NULL;
1434 }
1435
1436 result = ldm_frag_commit (&frags, ldb); /* Failures, already logged */
1437 out:
1438 if (data)
1439 put_dev_sector (sect);
1440 ldm_frag_free (&frags);
1441
1442 return result;
1443 }
1444
1445 /**
1446 * ldm_free_vblks - Free a linked list of vblk's
1447 * @lh: Head of a linked list of struct vblk
1448 *
1449 * Free a list of vblk's and free the memory used to maintain the list.
1450 *
1451 * Return: none
1452 */
ldm_free_vblks(struct list_head * lh)1453 static void ldm_free_vblks (struct list_head *lh)
1454 {
1455 struct list_head *item, *tmp;
1456
1457 BUG_ON (!lh);
1458
1459 list_for_each_safe (item, tmp, lh)
1460 kfree (list_entry (item, struct vblk, list));
1461 }
1462
1463
1464 /**
1465 * ldm_partition - Find out whether a device is a dynamic disk and handle it
1466 * @hd: gendisk structure in which to return the handled disk
1467 * @bdev: Device we need to look at
1468 * @first_sector: First sector within the device
1469 * @first_minor: First minor number of partitions for the device
1470 *
1471 * This determines whether the device @bdev is a dynamic disk and if so creates
1472 * the partitions necessary in the gendisk structure pointed to by @hd.
1473 *
1474 * We create a dummy device 1, which contains the LDM database, and then create
1475 * each partition described by the LDM database in sequence as devices 2+. For
1476 * example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
1477 * and so on: the actual data containing partitions.
1478 *
1479 * Return: 1 Success, @bdev is a dynamic disk and we handled it
1480 * 0 Success, @bdev is not a dynamic disk
1481 * -1 An error occurred before enough information had been read
1482 * Or @bdev is a dynamic disk, but it may be corrupted
1483 */
ldm_partition(struct gendisk * hd,struct block_device * bdev,unsigned long first_sector,int first_minor)1484 int ldm_partition (struct gendisk *hd, struct block_device *bdev,
1485 unsigned long first_sector, int first_minor)
1486 {
1487 struct ldmdb *ldb;
1488 unsigned long base;
1489 int result = -1;
1490
1491 BUG_ON (!hd);
1492 BUG_ON (!bdev);
1493
1494 /* Look for signs of a Dynamic Disk */
1495 if (!ldm_validate_partition_table (bdev))
1496 return 0;
1497
1498 ldb = kmalloc (sizeof (*ldb), GFP_KERNEL);
1499 if (!ldb) {
1500 ldm_crit ("Out of memory.");
1501 goto out;
1502 }
1503
1504 /* Parse and check privheads. */
1505 if (!ldm_validate_privheads (bdev, first_sector, &ldb->ph, hd, first_minor))
1506 goto out; /* Already logged */
1507
1508 /* All further references are relative to base (database start). */
1509 base = first_sector + ldb->ph.config_start;
1510
1511 /* Parse and check tocs and vmdb. */
1512 if (!ldm_validate_tocblocks (bdev, base, ldb) ||
1513 !ldm_validate_vmdb (bdev, base, ldb))
1514 goto out; /* Already logged */
1515
1516 /* Initialize vblk lists in ldmdb struct */
1517 INIT_LIST_HEAD (&ldb->v_dgrp);
1518 INIT_LIST_HEAD (&ldb->v_disk);
1519 INIT_LIST_HEAD (&ldb->v_volu);
1520 INIT_LIST_HEAD (&ldb->v_comp);
1521 INIT_LIST_HEAD (&ldb->v_part);
1522
1523 if (!ldm_get_vblks (bdev, base, ldb)) {
1524 ldm_crit ("Failed to read the VBLKs from the database.");
1525 goto cleanup;
1526 }
1527
1528 /* Finally, create the data partition devices. */
1529 if (ldm_create_data_partitions (hd, first_sector, first_minor, ldb)) {
1530 ldm_debug ("Parsed LDM database successfully.");
1531 result = 1;
1532 }
1533 /* else Already logged */
1534
1535 cleanup:
1536 ldm_free_vblks (&ldb->v_dgrp);
1537 ldm_free_vblks (&ldb->v_disk);
1538 ldm_free_vblks (&ldb->v_volu);
1539 ldm_free_vblks (&ldb->v_comp);
1540 ldm_free_vblks (&ldb->v_part);
1541 out:
1542 kfree (ldb);
1543 return result;
1544 }
1545
1546