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) 2001-2007 Anton Altaparmakov
6 * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
7 *
8 * Documentation is available at http://www.linux-ntfs.org/content/view/19/37/
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/pagemap.h>
28#include <linux/stringify.h>
29#include "ldm.h"
30#include "check.h"
31#include "msdos.h"
32
33/**
34 * ldm_debug/info/error/crit - Output an error message
35 * @f:    A printf format string containing the message
36 * @...:  Variables to substitute into @f
37 *
38 * ldm_debug() writes a DEBUG level message to the syslog but only if the
39 * driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
40 */
41#ifndef CONFIG_LDM_DEBUG
42#define ldm_debug(...)	do {} while (0)
43#else
44#define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __FUNCTION__, f, ##a)
45#endif
46
47#define ldm_crit(f, a...)  _ldm_printk (KERN_CRIT,  __FUNCTION__, f, ##a)
48#define ldm_error(f, a...) _ldm_printk (KERN_ERR,   __FUNCTION__, f, ##a)
49#define ldm_info(f, a...)  _ldm_printk (KERN_INFO,  __FUNCTION__, f, ##a)
50
51__attribute__ ((format (printf, 3, 4)))
52static void _ldm_printk (const char *level, const char *function,
53			 const char *fmt, ...)
54{
55	static char buf[128];
56	va_list args;
57
58	va_start (args, fmt);
59	vsnprintf (buf, sizeof (buf), fmt, args);
60	va_end (args);
61
62	printk ("%s%s(): %s\n", level, function, buf);
63}
64
65/**
66 * ldm_parse_hexbyte - Convert a ASCII hex number to a byte
67 * @src:  Pointer to at least 2 characters to convert.
68 *
69 * Convert a two character ASCII hex string to a number.
70 *
71 * Return:  0-255  Success, the byte was parsed correctly
72 *          -1     Error, an invalid character was supplied
73 */
74static int ldm_parse_hexbyte (const u8 *src)
75{
76	unsigned int x;		/* For correct wrapping */
77	int h;
78
79	/* high part */
80	if      ((x = src[0] - '0') <= '9'-'0') h = x;
81	else if ((x = src[0] - 'a') <= 'f'-'a') h = x+10;
82	else if ((x = src[0] - 'A') <= 'F'-'A') h = x+10;
83	else return -1;
84	h <<= 4;
85
86	/* low part */
87	if ((x = src[1] - '0') <= '9'-'0') return h | x;
88	if ((x = src[1] - 'a') <= 'f'-'a') return h | (x+10);
89	if ((x = src[1] - 'A') <= 'F'-'A') return h | (x+10);
90	return -1;
91}
92
93/**
94 * ldm_parse_guid - Convert GUID from ASCII to binary
95 * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
96 * @dest:  Memory block to hold binary GUID (16 bytes)
97 *
98 * N.B. The GUID need not be NULL terminated.
99 *
100 * Return:  'true'   @dest contains binary GUID
101 *          'false'  @dest contents are undefined
102 */
103static bool ldm_parse_guid (const u8 *src, u8 *dest)
104{
105	static const int size[] = { 4, 2, 2, 2, 6 };
106	int i, j, v;
107
108	if (src[8]  != '-' || src[13] != '-' ||
109	    src[18] != '-' || src[23] != '-')
110		return false;
111
112	for (j = 0; j < 5; j++, src++)
113		for (i = 0; i < size[j]; i++, src+=2, *dest++ = v)
114			if ((v = ldm_parse_hexbyte (src)) < 0)
115				return false;
116
117	return true;
118}
119
120/**
121 * ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
122 * @data:  Raw database PRIVHEAD structure loaded from the device
123 * @ph:    In-memory privhead structure in which to return parsed information
124 *
125 * This parses the LDM database PRIVHEAD structure supplied in @data and
126 * sets up the in-memory privhead structure @ph with the obtained information.
127 *
128 * Return:  'true'   @ph contains the PRIVHEAD data
129 *          'false'  @ph contents are undefined
130 */
131static bool ldm_parse_privhead(const u8 *data, struct privhead *ph)
132{
133	bool is_vista = false;
134
135	BUG_ON(!data || !ph);
136	if (MAGIC_PRIVHEAD != BE64(data)) {
137		ldm_error("Cannot find PRIVHEAD structure. LDM database is"
138			" corrupt. Aborting.");
139		return false;
140	}
141	ph->ver_major = BE16(data + 0x000C);
142	ph->ver_minor = BE16(data + 0x000E);
143	ph->logical_disk_start = BE64(data + 0x011B);
144	ph->logical_disk_size = BE64(data + 0x0123);
145	ph->config_start = BE64(data + 0x012B);
146	ph->config_size = BE64(data + 0x0133);
147	/* Version 2.11 is Win2k/XP and version 2.12 is Vista. */
148	if (ph->ver_major == 2 && ph->ver_minor == 12)
149		is_vista = true;
150	if (!is_vista && (ph->ver_major != 2 || ph->ver_minor != 11)) {
151		ldm_error("Expected PRIVHEAD version 2.11 or 2.12, got %d.%d."
152			" Aborting.", ph->ver_major, ph->ver_minor);
153		return false;
154	}
155	ldm_debug("PRIVHEAD version %d.%d (Windows %s).", ph->ver_major,
156			ph->ver_minor, is_vista ? "Vista" : "2000/XP");
157	if (ph->config_size != LDM_DB_SIZE) {	/* 1 MiB in sectors. */
158		/* Warn the user and continue, carefully. */
159		ldm_info("Database is normally %u bytes, it claims to "
160			"be %llu bytes.", LDM_DB_SIZE,
161			(unsigned long long)ph->config_size);
162	}
163	if ((ph->logical_disk_size == 0) || (ph->logical_disk_start +
164			ph->logical_disk_size > ph->config_start)) {
165		ldm_error("PRIVHEAD disk size doesn't match real disk size");
166		return false;
167	}
168	if (!ldm_parse_guid(data + 0x0030, ph->disk_id)) {
169		ldm_error("PRIVHEAD contains an invalid GUID.");
170		return false;
171	}
172	ldm_debug("Parsed PRIVHEAD successfully.");
173	return true;
174}
175
176/**
177 * ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
178 * @data:  Raw database TOCBLOCK structure loaded from the device
179 * @toc:   In-memory toc structure in which to return parsed information
180 *
181 * This parses the LDM Database TOCBLOCK (table of contents) structure supplied
182 * in @data and sets up the in-memory tocblock structure @toc with the obtained
183 * information.
184 *
185 * N.B.  The *_start and *_size values returned in @toc are not range-checked.
186 *
187 * Return:  'true'   @toc contains the TOCBLOCK data
188 *          'false'  @toc contents are undefined
189 */
190static bool ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
191{
192	BUG_ON (!data || !toc);
193
194	if (MAGIC_TOCBLOCK != BE64 (data)) {
195		ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
196		return false;
197	}
198	strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
199	toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
200	toc->bitmap1_start = BE64 (data + 0x2E);
201	toc->bitmap1_size  = BE64 (data + 0x36);
202
203	if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
204			sizeof (toc->bitmap1_name)) != 0) {
205		ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
206				TOC_BITMAP1, toc->bitmap1_name);
207		return false;
208	}
209	strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
210	toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
211	toc->bitmap2_start = BE64 (data + 0x50);
212	toc->bitmap2_size  = BE64 (data + 0x58);
213	if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
214			sizeof (toc->bitmap2_name)) != 0) {
215		ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
216				TOC_BITMAP2, toc->bitmap2_name);
217		return false;
218	}
219	ldm_debug ("Parsed TOCBLOCK successfully.");
220	return true;
221}
222
223/**
224 * ldm_parse_vmdb - Read the LDM Database VMDB structure
225 * @data:  Raw database VMDB structure loaded from the device
226 * @vm:    In-memory vmdb structure in which to return parsed information
227 *
228 * This parses the LDM Database VMDB structure supplied in @data and sets up
229 * the in-memory vmdb structure @vm with the obtained information.
230 *
231 * N.B.  The *_start, *_size and *_seq values will be range-checked later.
232 *
233 * Return:  'true'   @vm contains VMDB info
234 *          'false'  @vm contents are undefined
235 */
236static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
237{
238	BUG_ON (!data || !vm);
239
240	if (MAGIC_VMDB != BE32 (data)) {
241		ldm_crit ("Cannot find the VMDB, database may be corrupt.");
242		return false;
243	}
244
245	vm->ver_major = BE16 (data + 0x12);
246	vm->ver_minor = BE16 (data + 0x14);
247	if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
248		ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
249			"Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
250		return false;
251	}
252
253	vm->vblk_size     = BE32 (data + 0x08);
254	vm->vblk_offset   = BE32 (data + 0x0C);
255	vm->last_vblk_seq = BE32 (data + 0x04);
256
257	ldm_debug ("Parsed VMDB successfully.");
258	return true;
259}
260
261/**
262 * ldm_compare_privheads - Compare two privhead objects
263 * @ph1:  First privhead
264 * @ph2:  Second privhead
265 *
266 * This compares the two privhead structures @ph1 and @ph2.
267 *
268 * Return:  'true'   Identical
269 *          'false'  Different
270 */
271static bool ldm_compare_privheads (const struct privhead *ph1,
272				   const struct privhead *ph2)
273{
274	BUG_ON (!ph1 || !ph2);
275
276	return ((ph1->ver_major          == ph2->ver_major)		&&
277		(ph1->ver_minor          == ph2->ver_minor)		&&
278		(ph1->logical_disk_start == ph2->logical_disk_start)	&&
279		(ph1->logical_disk_size  == ph2->logical_disk_size)	&&
280		(ph1->config_start       == ph2->config_start)		&&
281		(ph1->config_size        == ph2->config_size)		&&
282		!memcmp (ph1->disk_id, ph2->disk_id, GUID_SIZE));
283}
284
285/**
286 * ldm_compare_tocblocks - Compare two tocblock objects
287 * @toc1:  First toc
288 * @toc2:  Second toc
289 *
290 * This compares the two tocblock structures @toc1 and @toc2.
291 *
292 * Return:  'true'   Identical
293 *          'false'  Different
294 */
295static bool ldm_compare_tocblocks (const struct tocblock *toc1,
296				   const struct tocblock *toc2)
297{
298	BUG_ON (!toc1 || !toc2);
299
300	return ((toc1->bitmap1_start == toc2->bitmap1_start)	&&
301		(toc1->bitmap1_size  == toc2->bitmap1_size)	&&
302		(toc1->bitmap2_start == toc2->bitmap2_start)	&&
303		(toc1->bitmap2_size  == toc2->bitmap2_size)	&&
304		!strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
305			sizeof (toc1->bitmap1_name))		&&
306		!strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
307			sizeof (toc1->bitmap2_name)));
308}
309
310/**
311 * ldm_validate_privheads - Compare the primary privhead with its backups
312 * @bdev:  Device holding the LDM Database
313 * @ph1:   Memory struct to fill with ph contents
314 *
315 * Read and compare all three privheads from disk.
316 *
317 * The privheads on disk show the size and location of the main disk area and
318 * the configuration area (the database).  The values are range-checked against
319 * @hd, which contains the real size of the disk.
320 *
321 * Return:  'true'   Success
322 *          'false'  Error
323 */
324static bool ldm_validate_privheads (struct block_device *bdev,
325				    struct privhead *ph1)
326{
327	static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
328	struct privhead *ph[3] = { ph1 };
329	Sector sect;
330	u8 *data;
331	bool result = false;
332	long num_sects;
333	int i;
334
335	BUG_ON (!bdev || !ph1);
336
337	ph[1] = kmalloc (sizeof (*ph[1]), GFP_KERNEL);
338	ph[2] = kmalloc (sizeof (*ph[2]), GFP_KERNEL);
339	if (!ph[1] || !ph[2]) {
340		ldm_crit ("Out of memory.");
341		goto out;
342	}
343
344	/* off[1 & 2] are relative to ph[0]->config_start */
345	ph[0]->config_start = 0;
346
347	/* Read and parse privheads */
348	for (i = 0; i < 3; i++) {
349		data = read_dev_sector (bdev,
350			ph[0]->config_start + off[i], &sect);
351		if (!data) {
352			ldm_crit ("Disk read failed.");
353			goto out;
354		}
355		result = ldm_parse_privhead (data, ph[i]);
356		put_dev_sector (sect);
357		if (!result) {
358			ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
359			if (i < 2)
360				goto out;	/* Already logged */
361			else
362				break;
363		}
364	}
365
366	num_sects = bdev->bd_inode->i_size >> 9;
367
368	if ((ph[0]->config_start > num_sects) ||
369	   ((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
370		ldm_crit ("Database extends beyond the end of the disk.");
371		goto out;
372	}
373
374	if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
375	   ((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
376		    > ph[0]->config_start)) {
377		ldm_crit ("Disk and database overlap.");
378		goto out;
379	}
380
381	if (!ldm_compare_privheads (ph[0], ph[1])) {
382		ldm_crit ("Primary and backup PRIVHEADs don't match.");
383		goto out;
384	}
385	ldm_debug ("Validated PRIVHEADs successfully.");
386	result = true;
387out:
388	kfree (ph[1]);
389	kfree (ph[2]);
390	return result;
391}
392
393/**
394 * ldm_validate_tocblocks - Validate the table of contents and its backups
395 * @bdev:  Device holding the LDM Database
396 * @base:  Offset, into @bdev, of the database
397 * @ldb:   Cache of the database structures
398 *
399 * Find and compare the four tables of contents of the LDM Database stored on
400 * @bdev and return the parsed information into @toc1.
401 *
402 * The offsets and sizes of the configs are range-checked against a privhead.
403 *
404 * Return:  'true'   @toc1 contains validated TOCBLOCK info
405 *          'false'  @toc1 contents are undefined
406 */
407static bool ldm_validate_tocblocks(struct block_device *bdev,
408	unsigned long base, struct ldmdb *ldb)
409{
410	static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
411	struct tocblock *tb[4];
412	struct privhead *ph;
413	Sector sect;
414	u8 *data;
415	int i, nr_tbs;
416	bool result = false;
417
418	BUG_ON(!bdev || !ldb);
419	ph = &ldb->ph;
420	tb[0] = &ldb->toc;
421	tb[1] = kmalloc(sizeof(*tb[1]) * 3, GFP_KERNEL);
422	if (!tb[1]) {
423		ldm_crit("Out of memory.");
424		goto err;
425	}
426	tb[2] = (struct tocblock*)((u8*)tb[1] + sizeof(*tb[1]));
427	tb[3] = (struct tocblock*)((u8*)tb[2] + sizeof(*tb[2]));
428	/*
429	 * Try to read and parse all four TOCBLOCKs.
430	 *
431	 * Windows Vista LDM v2.12 does not always have all four TOCBLOCKs so
432	 * skip any that fail as long as we get at least one valid TOCBLOCK.
433	 */
434	for (nr_tbs = i = 0; i < 4; i++) {
435		data = read_dev_sector(bdev, base + off[i], &sect);
436		if (!data) {
437			ldm_error("Disk read failed for TOCBLOCK %d.", i);
438			continue;
439		}
440		if (ldm_parse_tocblock(data, tb[nr_tbs]))
441			nr_tbs++;
442		put_dev_sector(sect);
443	}
444	if (!nr_tbs) {
445		ldm_crit("Failed to find a valid TOCBLOCK.");
446		goto err;
447	}
448	/* Range check the TOCBLOCK against a privhead. */
449	if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
450			((tb[0]->bitmap2_start + tb[0]->bitmap2_size) >
451			ph->config_size)) {
452		ldm_crit("The bitmaps are out of range.  Giving up.");
453		goto err;
454	}
455	/* Compare all loaded TOCBLOCKs. */
456	for (i = 1; i < nr_tbs; i++) {
457		if (!ldm_compare_tocblocks(tb[0], tb[i])) {
458			ldm_crit("TOCBLOCKs 0 and %d do not match.", i);
459			goto err;
460		}
461	}
462	ldm_debug("Validated %d TOCBLOCKs successfully.", nr_tbs);
463	result = true;
464err:
465	kfree(tb[1]);
466	return result;
467}
468
469/**
470 * ldm_validate_vmdb - Read the VMDB and validate it
471 * @bdev:  Device holding the LDM Database
472 * @base:  Offset, into @bdev, of the database
473 * @ldb:   Cache of the database structures
474 *
475 * Find the vmdb of the LDM Database stored on @bdev and return the parsed
476 * information in @ldb.
477 *
478 * Return:  'true'   @ldb contains validated VBDB info
479 *          'false'  @ldb contents are undefined
480 */
481static bool ldm_validate_vmdb (struct block_device *bdev, unsigned long base,
482			       struct ldmdb *ldb)
483{
484	Sector sect;
485	u8 *data;
486	bool result = false;
487	struct vmdb *vm;
488	struct tocblock *toc;
489
490	BUG_ON (!bdev || !ldb);
491
492	vm  = &ldb->vm;
493	toc = &ldb->toc;
494
495	data = read_dev_sector (bdev, base + OFF_VMDB, &sect);
496	if (!data) {
497		ldm_crit ("Disk read failed.");
498		return false;
499	}
500
501	if (!ldm_parse_vmdb (data, vm))
502		goto out;				/* Already logged */
503
504	/* Are there uncommitted transactions? */
505	if (BE16(data + 0x10) != 0x01) {
506		ldm_crit ("Database is not in a consistent state.  Aborting.");
507		goto out;
508	}
509
510	if (vm->vblk_offset != 512)
511		ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
512
513	/*
514	 * The last_vblkd_seq can be before the end of the vmdb, just make sure
515	 * it is not out of bounds.
516	 */
517	if ((vm->vblk_size * vm->last_vblk_seq) > (toc->bitmap1_size << 9)) {
518		ldm_crit ("VMDB exceeds allowed size specified by TOCBLOCK.  "
519				"Database is corrupt.  Aborting.");
520		goto out;
521	}
522
523	result = true;
524out:
525	put_dev_sector (sect);
526	return result;
527}
528
529
530/**
531 * ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
532 * @bdev:  Device holding the LDM Database
533 *
534 * This function provides a weak test to decide whether the device is a dynamic
535 * disk or not.  It looks for an MS-DOS-style partition table containing at
536 * least one partition of type 0x42 (formerly SFS, now used by Windows for
537 * dynamic disks).
538 *
539 * N.B.  The only possible error can come from the read_dev_sector and that is
540 *       only likely to happen if the underlying device is strange.  If that IS
541 *       the case we should return zero to let someone else try.
542 *
543 * Return:  'true'   @bdev is a dynamic disk
544 *          'false'  @bdev is not a dynamic disk, or an error occurred
545 */
546static bool ldm_validate_partition_table (struct block_device *bdev)
547{
548	Sector sect;
549	u8 *data;
550	struct partition *p;
551	int i;
552	bool result = false;
553
554	BUG_ON (!bdev);
555
556	data = read_dev_sector (bdev, 0, &sect);
557	if (!data) {
558		ldm_crit ("Disk read failed.");
559		return false;
560	}
561
562	if (*(__le16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC))
563		goto out;
564
565	p = (struct partition*)(data + 0x01BE);
566	for (i = 0; i < 4; i++, p++)
567		if (SYS_IND (p) == LDM_PARTITION) {
568			result = true;
569			break;
570		}
571
572	if (result)
573		ldm_debug ("Found W2K dynamic disk partition type.");
574
575out:
576	put_dev_sector (sect);
577	return result;
578}
579
580/**
581 * ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
582 * @ldb:  Cache of the database structures
583 *
584 * The LDM Database contains a list of all partitions on all dynamic disks.
585 * The primary PRIVHEAD, at the beginning of the physical disk, tells us
586 * the GUID of this disk.  This function searches for the GUID in a linked
587 * list of vblk's.
588 *
589 * Return:  Pointer, A matching vblk was found
590 *          NULL,    No match, or an error
591 */
592static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
593{
594	struct list_head *item;
595
596	BUG_ON (!ldb);
597
598	list_for_each (item, &ldb->v_disk) {
599		struct vblk *v = list_entry (item, struct vblk, list);
600		if (!memcmp (v->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
601			return v;
602	}
603
604	return NULL;
605}
606
607/**
608 * ldm_create_data_partitions - Create data partitions for this device
609 * @pp:   List of the partitions parsed so far
610 * @ldb:  Cache of the database structures
611 *
612 * The database contains ALL the partitions for ALL disk groups, so we need to
613 * filter out this specific disk. Using the disk's object id, we can find all
614 * the partitions in the database that belong to this disk.
615 *
616 * Add each partition in our database, to the parsed_partitions structure.
617 *
618 * N.B.  This function creates the partitions in the order it finds partition
619 *       objects in the linked list.
620 *
621 * Return:  'true'   Partition created
622 *          'false'  Error, probably a range checking problem
623 */
624static bool ldm_create_data_partitions (struct parsed_partitions *pp,
625					const struct ldmdb *ldb)
626{
627	struct list_head *item;
628	struct vblk *vb;
629	struct vblk *disk;
630	struct vblk_part *part;
631	int part_num = 1;
632
633	BUG_ON (!pp || !ldb);
634
635	disk = ldm_get_disk_objid (ldb);
636	if (!disk) {
637		ldm_crit ("Can't find the ID of this disk in the database.");
638		return false;
639	}
640
641	printk (" [LDM]");
642
643	/* Create the data partitions */
644	list_for_each (item, &ldb->v_part) {
645		vb = list_entry (item, struct vblk, list);
646		part = &vb->vblk.part;
647
648		if (part->disk_id != disk->obj_id)
649			continue;
650
651		put_partition (pp, part_num, ldb->ph.logical_disk_start +
652				part->start, part->size);
653		part_num++;
654	}
655
656	printk ("\n");
657	return true;
658}
659
660
661/**
662 * ldm_relative - Calculate the next relative offset
663 * @buffer:  Block of data being worked on
664 * @buflen:  Size of the block of data
665 * @base:    Size of the previous fixed width fields
666 * @offset:  Cumulative size of the previous variable-width fields
667 *
668 * Because many of the VBLK fields are variable-width, it's necessary
669 * to calculate each offset based on the previous one and the length
670 * of the field it pointed to.
671 *
672 * Return:  -1 Error, the calculated offset exceeded the size of the buffer
673 *           n OK, a range-checked offset into buffer
674 */
675static int ldm_relative (const u8 *buffer, int buflen, int base, int offset)
676{
677
678	base += offset;
679	if ((!buffer) || (offset < 0) || (base > buflen))
680		return -1;
681	if ((base + buffer[base]) >= buflen)
682		return -1;
683
684	return buffer[base] + offset + 1;
685}
686
687/**
688 * ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
689 * @block:  Pointer to the variable-width number to convert
690 *
691 * Large numbers in the LDM Database are often stored in a packed format.  Each
692 * number is prefixed by a one byte width marker.  All numbers in the database
693 * are stored in big-endian byte order.  This function reads one of these
694 * numbers and returns the result
695 *
696 * N.B.  This function DOES NOT perform any range checking, though the most
697 *       it will read is eight bytes.
698 *
699 * Return:  n A number
700 *          0 Zero, or an error occurred
701 */
702static u64 ldm_get_vnum (const u8 *block)
703{
704	u64 tmp = 0;
705	u8 length;
706
707	BUG_ON (!block);
708
709	length = *block++;
710
711	if (length && length <= 8)
712		while (length--)
713			tmp = (tmp << 8) | *block++;
714	else
715		ldm_error ("Illegal length %d.", length);
716
717	return tmp;
718}
719
720/**
721 * ldm_get_vstr - Read a length-prefixed string into a buffer
722 * @block:   Pointer to the length marker
723 * @buffer:  Location to copy string to
724 * @buflen:  Size of the output buffer
725 *
726 * Many of the strings in the LDM Database are not NULL terminated.  Instead
727 * they are prefixed by a one byte length marker.  This function copies one of
728 * these strings into a buffer.
729 *
730 * N.B.  This function DOES NOT perform any range checking on the input.
731 *       If the buffer is too small, the output will be truncated.
732 *
733 * Return:  0, Error and @buffer contents are undefined
734 *          n, String length in characters (excluding NULL)
735 *          buflen-1, String was truncated.
736 */
737static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
738{
739	int length;
740
741	BUG_ON (!block || !buffer);
742
743	length = block[0];
744	if (length >= buflen) {
745		ldm_error ("Truncating string %d -> %d.", length, buflen);
746		length = buflen - 1;
747	}
748	memcpy (buffer, block + 1, length);
749	buffer[length] = 0;
750	return length;
751}
752
753
754/**
755 * ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
756 * @buffer:  Block of data being worked on
757 * @buflen:  Size of the block of data
758 * @vb:      In-memory vblk in which to return information
759 *
760 * Read a raw VBLK Component object (version 3) into a vblk structure.
761 *
762 * Return:  'true'   @vb contains a Component VBLK
763 *          'false'  @vb contents are not defined
764 */
765static bool ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
766{
767	int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
768	struct vblk_comp *comp;
769
770	BUG_ON (!buffer || !vb);
771
772	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
773	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
774	r_vstate = ldm_relative (buffer, buflen, 0x18, r_name);
775	r_child  = ldm_relative (buffer, buflen, 0x1D, r_vstate);
776	r_parent = ldm_relative (buffer, buflen, 0x2D, r_child);
777
778	if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
779		r_stripe = ldm_relative (buffer, buflen, 0x2E, r_parent);
780		r_cols   = ldm_relative (buffer, buflen, 0x2E, r_stripe);
781		len = r_cols;
782	} else {
783		r_stripe = 0;
784		r_cols   = 0;
785		len = r_parent;
786	}
787	if (len < 0)
788		return false;
789
790	len += VBLK_SIZE_CMP3;
791	if (len != BE32 (buffer + 0x14))
792		return false;
793
794	comp = &vb->vblk.comp;
795	ldm_get_vstr (buffer + 0x18 + r_name, comp->state,
796		sizeof (comp->state));
797	comp->type      = buffer[0x18 + r_vstate];
798	comp->children  = ldm_get_vnum (buffer + 0x1D + r_vstate);
799	comp->parent_id = ldm_get_vnum (buffer + 0x2D + r_child);
800	comp->chunksize = r_stripe ? ldm_get_vnum (buffer+r_parent+0x2E) : 0;
801
802	return true;
803}
804
805/**
806 * ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
807 * @buffer:  Block of data being worked on
808 * @buflen:  Size of the block of data
809 * @vb:      In-memory vblk in which to return information
810 *
811 * Read a raw VBLK Disk Group object (version 3) into a vblk structure.
812 *
813 * Return:  'true'   @vb contains a Disk Group VBLK
814 *          'false'  @vb contents are not defined
815 */
816static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
817{
818	int r_objid, r_name, r_diskid, r_id1, r_id2, len;
819	struct vblk_dgrp *dgrp;
820
821	BUG_ON (!buffer || !vb);
822
823	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
824	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
825	r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
826
827	if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
828		r_id1 = ldm_relative (buffer, buflen, 0x24, r_diskid);
829		r_id2 = ldm_relative (buffer, buflen, 0x24, r_id1);
830		len = r_id2;
831	} else {
832		r_id1 = 0;
833		r_id2 = 0;
834		len = r_diskid;
835	}
836	if (len < 0)
837		return false;
838
839	len += VBLK_SIZE_DGR3;
840	if (len != BE32 (buffer + 0x14))
841		return false;
842
843	dgrp = &vb->vblk.dgrp;
844	ldm_get_vstr (buffer + 0x18 + r_name, dgrp->disk_id,
845		sizeof (dgrp->disk_id));
846	return true;
847}
848
849/**
850 * ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
851 * @buffer:  Block of data being worked on
852 * @buflen:  Size of the block of data
853 * @vb:      In-memory vblk in which to return information
854 *
855 * Read a raw VBLK Disk Group object (version 4) into a vblk structure.
856 *
857 * Return:  'true'   @vb contains a Disk Group VBLK
858 *          'false'  @vb contents are not defined
859 */
860static bool ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
861{
862	char buf[64];
863	int r_objid, r_name, r_id1, r_id2, len;
864	struct vblk_dgrp *dgrp;
865
866	BUG_ON (!buffer || !vb);
867
868	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
869	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
870
871	if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
872		r_id1 = ldm_relative (buffer, buflen, 0x44, r_name);
873		r_id2 = ldm_relative (buffer, buflen, 0x44, r_id1);
874		len = r_id2;
875	} else {
876		r_id1 = 0;
877		r_id2 = 0;
878		len = r_name;
879	}
880	if (len < 0)
881		return false;
882
883	len += VBLK_SIZE_DGR4;
884	if (len != BE32 (buffer + 0x14))
885		return false;
886
887	dgrp = &vb->vblk.dgrp;
888
889	ldm_get_vstr (buffer + 0x18 + r_objid, buf, sizeof (buf));
890	return true;
891}
892
893/**
894 * ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
895 * @buffer:  Block of data being worked on
896 * @buflen:  Size of the block of data
897 * @vb:      In-memory vblk in which to return information
898 *
899 * Read a raw VBLK Disk object (version 3) into a vblk structure.
900 *
901 * Return:  'true'   @vb contains a Disk VBLK
902 *          'false'  @vb contents are not defined
903 */
904static bool ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
905{
906	int r_objid, r_name, r_diskid, r_altname, len;
907	struct vblk_disk *disk;
908
909	BUG_ON (!buffer || !vb);
910
911	r_objid   = ldm_relative (buffer, buflen, 0x18, 0);
912	r_name    = ldm_relative (buffer, buflen, 0x18, r_objid);
913	r_diskid  = ldm_relative (buffer, buflen, 0x18, r_name);
914	r_altname = ldm_relative (buffer, buflen, 0x18, r_diskid);
915	len = r_altname;
916	if (len < 0)
917		return false;
918
919	len += VBLK_SIZE_DSK3;
920	if (len != BE32 (buffer + 0x14))
921		return false;
922
923	disk = &vb->vblk.disk;
924	ldm_get_vstr (buffer + 0x18 + r_diskid, disk->alt_name,
925		sizeof (disk->alt_name));
926	if (!ldm_parse_guid (buffer + 0x19 + r_name, disk->disk_id))
927		return false;
928
929	return true;
930}
931
932/**
933 * ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
934 * @buffer:  Block of data being worked on
935 * @buflen:  Size of the block of data
936 * @vb:      In-memory vblk in which to return information
937 *
938 * Read a raw VBLK Disk object (version 4) into a vblk structure.
939 *
940 * Return:  'true'   @vb contains a Disk VBLK
941 *          'false'  @vb contents are not defined
942 */
943static bool ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
944{
945	int r_objid, r_name, len;
946	struct vblk_disk *disk;
947
948	BUG_ON (!buffer || !vb);
949
950	r_objid = ldm_relative (buffer, buflen, 0x18, 0);
951	r_name  = ldm_relative (buffer, buflen, 0x18, r_objid);
952	len     = r_name;
953	if (len < 0)
954		return false;
955
956	len += VBLK_SIZE_DSK4;
957	if (len != BE32 (buffer + 0x14))
958		return false;
959
960	disk = &vb->vblk.disk;
961	memcpy (disk->disk_id, buffer + 0x18 + r_name, GUID_SIZE);
962	return true;
963}
964
965/**
966 * ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
967 * @buffer:  Block of data being worked on
968 * @buflen:  Size of the block of data
969 * @vb:      In-memory vblk in which to return information
970 *
971 * Read a raw VBLK Partition object (version 3) into a vblk structure.
972 *
973 * Return:  'true'   @vb contains a Partition VBLK
974 *          'false'  @vb contents are not defined
975 */
976static bool ldm_parse_prt3(const u8 *buffer, int buflen, struct vblk *vb)
977{
978	int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
979	struct vblk_part *part;
980
981	BUG_ON(!buffer || !vb);
982	r_objid = ldm_relative(buffer, buflen, 0x18, 0);
983	if (r_objid < 0) {
984		ldm_error("r_objid %d < 0", r_objid);
985		return false;
986	}
987	r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
988	if (r_name < 0) {
989		ldm_error("r_name %d < 0", r_name);
990		return false;
991	}
992	r_size = ldm_relative(buffer, buflen, 0x34, r_name);
993	if (r_size < 0) {
994		ldm_error("r_size %d < 0", r_size);
995		return false;
996	}
997	r_parent = ldm_relative(buffer, buflen, 0x34, r_size);
998	if (r_parent < 0) {
999		ldm_error("r_parent %d < 0", r_parent);
1000		return false;
1001	}
1002	r_diskid = ldm_relative(buffer, buflen, 0x34, r_parent);
1003	if (r_diskid < 0) {
1004		ldm_error("r_diskid %d < 0", r_diskid);
1005		return false;
1006	}
1007	if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
1008		r_index = ldm_relative(buffer, buflen, 0x34, r_diskid);
1009		if (r_index < 0) {
1010			ldm_error("r_index %d < 0", r_index);
1011			return false;
1012		}
1013		len = r_index;
1014	} else {
1015		r_index = 0;
1016		len = r_diskid;
1017	}
1018	if (len < 0) {
1019		ldm_error("len %d < 0", len);
1020		return false;
1021	}
1022	len += VBLK_SIZE_PRT3;
1023	if (len > BE32(buffer + 0x14)) {
1024		ldm_error("len %d > BE32(buffer + 0x14) %d", len,
1025				BE32(buffer + 0x14));
1026		return false;
1027	}
1028	part = &vb->vblk.part;
1029	part->start = BE64(buffer + 0x24 + r_name);
1030	part->volume_offset = BE64(buffer + 0x2C + r_name);
1031	part->size = ldm_get_vnum(buffer + 0x34 + r_name);
1032	part->parent_id = ldm_get_vnum(buffer + 0x34 + r_size);
1033	part->disk_id = ldm_get_vnum(buffer + 0x34 + r_parent);
1034	if (vb->flags & VBLK_FLAG_PART_INDEX)
1035		part->partnum = buffer[0x35 + r_diskid];
1036	else
1037		part->partnum = 0;
1038	return true;
1039}
1040
1041/**
1042 * ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
1043 * @buffer:  Block of data being worked on
1044 * @buflen:  Size of the block of data
1045 * @vb:      In-memory vblk in which to return information
1046 *
1047 * Read a raw VBLK Volume object (version 5) into a vblk structure.
1048 *
1049 * Return:  'true'   @vb contains a Volume VBLK
1050 *          'false'  @vb contents are not defined
1051 */
1052static bool ldm_parse_vol5 (const u8 *buffer, int buflen, struct vblk *vb)
1053{
1054	int r_objid, r_name, r_vtype, r_child, r_size, r_id1, r_id2, r_size2;
1055	int r_drive, len;
1056	struct vblk_volu *volu;
1057
1058	BUG_ON (!buffer || !vb);
1059
1060	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
1061	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
1062	r_vtype  = ldm_relative (buffer, buflen, 0x18, r_name);
1063	r_child  = ldm_relative (buffer, buflen, 0x2E, r_vtype);
1064	r_size   = ldm_relative (buffer, buflen, 0x3E, r_child);
1065
1066	if (buffer[0x12] & VBLK_FLAG_VOLU_ID1)
1067		r_id1 = ldm_relative (buffer, buflen, 0x53, r_size);
1068	else
1069		r_id1 = r_size;
1070
1071	if (buffer[0x12] & VBLK_FLAG_VOLU_ID2)
1072		r_id2 = ldm_relative (buffer, buflen, 0x53, r_id1);
1073	else
1074		r_id2 = r_id1;
1075
1076	if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE)
1077		r_size2 = ldm_relative (buffer, buflen, 0x53, r_id2);
1078	else
1079		r_size2 = r_id2;
1080
1081	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE)
1082		r_drive = ldm_relative (buffer, buflen, 0x53, r_size2);
1083	else
1084		r_drive = r_size2;
1085
1086	len = r_drive;
1087	if (len < 0)
1088		return false;
1089
1090	len += VBLK_SIZE_VOL5;
1091	if (len != BE32 (buffer + 0x14))
1092		return false;
1093
1094	volu = &vb->vblk.volu;
1095
1096	ldm_get_vstr (buffer + 0x18 + r_name,  volu->volume_type,
1097		sizeof (volu->volume_type));
1098	memcpy (volu->volume_state, buffer + 0x19 + r_vtype,
1099			sizeof (volu->volume_state));
1100	volu->size = ldm_get_vnum (buffer + 0x3E + r_child);
1101	volu->partition_type = buffer[0x42 + r_size];
1102	memcpy (volu->guid, buffer + 0x43 + r_size,  sizeof (volu->guid));
1103	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1104		ldm_get_vstr (buffer + 0x53 + r_size,  volu->drive_hint,
1105			sizeof (volu->drive_hint));
1106	}
1107	return true;
1108}
1109
1110/**
1111 * ldm_parse_vblk - Read a raw VBLK object into a vblk structure
1112 * @buf:  Block of data being worked on
1113 * @len:  Size of the block of data
1114 * @vb:   In-memory vblk in which to return information
1115 *
1116 * Read a raw VBLK object into a vblk structure.  This function just reads the
1117 * information common to all VBLK types, then delegates the rest of the work to
1118 * helper functions: ldm_parse_*.
1119 *
1120 * Return:  'true'   @vb contains a VBLK
1121 *          'false'  @vb contents are not defined
1122 */
1123static bool ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
1124{
1125	bool result = false;
1126	int r_objid;
1127
1128	BUG_ON (!buf || !vb);
1129
1130	r_objid = ldm_relative (buf, len, 0x18, 0);
1131	if (r_objid < 0) {
1132		ldm_error ("VBLK header is corrupt.");
1133		return false;
1134	}
1135
1136	vb->flags  = buf[0x12];
1137	vb->type   = buf[0x13];
1138	vb->obj_id = ldm_get_vnum (buf + 0x18);
1139	ldm_get_vstr (buf+0x18+r_objid, vb->name, sizeof (vb->name));
1140
1141	switch (vb->type) {
1142		case VBLK_CMP3:  result = ldm_parse_cmp3 (buf, len, vb); break;
1143		case VBLK_DSK3:  result = ldm_parse_dsk3 (buf, len, vb); break;
1144		case VBLK_DSK4:  result = ldm_parse_dsk4 (buf, len, vb); break;
1145		case VBLK_DGR3:  result = ldm_parse_dgr3 (buf, len, vb); break;
1146		case VBLK_DGR4:  result = ldm_parse_dgr4 (buf, len, vb); break;
1147		case VBLK_PRT3:  result = ldm_parse_prt3 (buf, len, vb); break;
1148		case VBLK_VOL5:  result = ldm_parse_vol5 (buf, len, vb); break;
1149	}
1150
1151	if (result)
1152		ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
1153			 (unsigned long long) vb->obj_id, vb->type);
1154	else
1155		ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
1156			(unsigned long long) vb->obj_id, vb->type);
1157
1158	return result;
1159}
1160
1161
1162/**
1163 * ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
1164 * @data:  Raw VBLK to add to the database
1165 * @len:   Size of the raw VBLK
1166 * @ldb:   Cache of the database structures
1167 *
1168 * The VBLKs are sorted into categories.  Partitions are also sorted by offset.
1169 *
1170 * N.B.  This function does not check the validity of the VBLKs.
1171 *
1172 * Return:  'true'   The VBLK was added
1173 *          'false'  An error occurred
1174 */
1175static bool ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
1176{
1177	struct vblk *vb;
1178	struct list_head *item;
1179
1180	BUG_ON (!data || !ldb);
1181
1182	vb = kmalloc (sizeof (*vb), GFP_KERNEL);
1183	if (!vb) {
1184		ldm_crit ("Out of memory.");
1185		return false;
1186	}
1187
1188	if (!ldm_parse_vblk (data, len, vb)) {
1189		kfree(vb);
1190		return false;			/* Already logged */
1191	}
1192
1193	/* Put vblk into the correct list. */
1194	switch (vb->type) {
1195	case VBLK_DGR3:
1196	case VBLK_DGR4:
1197		list_add (&vb->list, &ldb->v_dgrp);
1198		break;
1199	case VBLK_DSK3:
1200	case VBLK_DSK4:
1201		list_add (&vb->list, &ldb->v_disk);
1202		break;
1203	case VBLK_VOL5:
1204		list_add (&vb->list, &ldb->v_volu);
1205		break;
1206	case VBLK_CMP3:
1207		list_add (&vb->list, &ldb->v_comp);
1208		break;
1209	case VBLK_PRT3:
1210		/* Sort by the partition's start sector. */
1211		list_for_each (item, &ldb->v_part) {
1212			struct vblk *v = list_entry (item, struct vblk, list);
1213			if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
1214			    (v->vblk.part.start > vb->vblk.part.start)) {
1215				list_add_tail (&vb->list, &v->list);
1216				return true;
1217			}
1218		}
1219		list_add_tail (&vb->list, &ldb->v_part);
1220		break;
1221	}
1222	return true;
1223}
1224
1225/**
1226 * ldm_frag_add - Add a VBLK fragment to a list
1227 * @data:   Raw fragment to be added to the list
1228 * @size:   Size of the raw fragment
1229 * @frags:  Linked list of VBLK fragments
1230 *
1231 * Fragmented VBLKs may not be consecutive in the database, so they are placed
1232 * in a list so they can be pieced together later.
1233 *
1234 * Return:  'true'   Success, the VBLK was added to the list
1235 *          'false'  Error, a problem occurred
1236 */
1237static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
1238{
1239	struct frag *f;
1240	struct list_head *item;
1241	int rec, num, group;
1242
1243	BUG_ON (!data || !frags);
1244
1245	group = BE32 (data + 0x08);
1246	rec   = BE16 (data + 0x0C);
1247	num   = BE16 (data + 0x0E);
1248	if ((num < 1) || (num > 4)) {
1249		ldm_error ("A VBLK claims to have %d parts.", num);
1250		return false;
1251	}
1252
1253	list_for_each (item, frags) {
1254		f = list_entry (item, struct frag, list);
1255		if (f->group == group)
1256			goto found;
1257	}
1258
1259	f = kmalloc (sizeof (*f) + size*num, GFP_KERNEL);
1260	if (!f) {
1261		ldm_crit ("Out of memory.");
1262		return false;
1263	}
1264
1265	f->group = group;
1266	f->num   = num;
1267	f->rec   = rec;
1268	f->map   = 0xFF << num;
1269
1270	list_add_tail (&f->list, frags);
1271found:
1272	if (f->map & (1 << rec)) {
1273		ldm_error ("Duplicate VBLK, part %d.", rec);
1274		f->map &= 0x7F;			/* Mark the group as broken */
1275		return false;
1276	}
1277
1278	f->map |= (1 << rec);
1279
1280	if (num > 0) {
1281		data += VBLK_SIZE_HEAD;
1282		size -= VBLK_SIZE_HEAD;
1283	}
1284	memcpy (f->data+rec*(size-VBLK_SIZE_HEAD)+VBLK_SIZE_HEAD, data, size);
1285
1286	return true;
1287}
1288
1289/**
1290 * ldm_frag_free - Free a linked list of VBLK fragments
1291 * @list:  Linked list of fragments
1292 *
1293 * Free a linked list of VBLK fragments
1294 *
1295 * Return:  none
1296 */
1297static void ldm_frag_free (struct list_head *list)
1298{
1299	struct list_head *item, *tmp;
1300
1301	BUG_ON (!list);
1302
1303	list_for_each_safe (item, tmp, list)
1304		kfree (list_entry (item, struct frag, list));
1305}
1306
1307/**
1308 * ldm_frag_commit - Validate fragmented VBLKs and add them to the database
1309 * @frags:  Linked list of VBLK fragments
1310 * @ldb:    Cache of the database structures
1311 *
1312 * Now that all the fragmented VBLKs have been collected, they must be added to
1313 * the database for later use.
1314 *
1315 * Return:  'true'   All the fragments we added successfully
1316 *          'false'  One or more of the fragments we invalid
1317 */
1318static bool ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
1319{
1320	struct frag *f;
1321	struct list_head *item;
1322
1323	BUG_ON (!frags || !ldb);
1324
1325	list_for_each (item, frags) {
1326		f = list_entry (item, struct frag, list);
1327
1328		if (f->map != 0xFF) {
1329			ldm_error ("VBLK group %d is incomplete (0x%02x).",
1330				f->group, f->map);
1331			return false;
1332		}
1333
1334		if (!ldm_ldmdb_add (f->data, f->num*ldb->vm.vblk_size, ldb))
1335			return false;		/* Already logged */
1336	}
1337	return true;
1338}
1339
1340/**
1341 * ldm_get_vblks - Read the on-disk database of VBLKs into memory
1342 * @bdev:  Device holding the LDM Database
1343 * @base:  Offset, into @bdev, of the database
1344 * @ldb:   Cache of the database structures
1345 *
1346 * To use the information from the VBLKs, they need to be read from the disk,
1347 * unpacked and validated.  We cache them in @ldb according to their type.
1348 *
1349 * Return:  'true'   All the VBLKs were read successfully
1350 *          'false'  An error occurred
1351 */
1352static bool ldm_get_vblks (struct block_device *bdev, unsigned long base,
1353			   struct ldmdb *ldb)
1354{
1355	int size, perbuf, skip, finish, s, v, recs;
1356	u8 *data = NULL;
1357	Sector sect;
1358	bool result = false;
1359	LIST_HEAD (frags);
1360
1361	BUG_ON (!bdev || !ldb);
1362
1363	size   = ldb->vm.vblk_size;
1364	perbuf = 512 / size;
1365	skip   = ldb->vm.vblk_offset >> 9;		/* Bytes to sectors */
1366	finish = (size * ldb->vm.last_vblk_seq) >> 9;
1367
1368	for (s = skip; s < finish; s++) {		/* For each sector */
1369		data = read_dev_sector (bdev, base + OFF_VMDB + s, &sect);
1370		if (!data) {
1371			ldm_crit ("Disk read failed.");
1372			goto out;
1373		}
1374
1375		for (v = 0; v < perbuf; v++, data+=size) {  /* For each vblk */
1376			if (MAGIC_VBLK != BE32 (data)) {
1377				ldm_error ("Expected to find a VBLK.");
1378				goto out;
1379			}
1380
1381			recs = BE16 (data + 0x0E);	/* Number of records */
1382			if (recs == 1) {
1383				if (!ldm_ldmdb_add (data, size, ldb))
1384					goto out;	/* Already logged */
1385			} else if (recs > 1) {
1386				if (!ldm_frag_add (data, size, &frags))
1387					goto out;	/* Already logged */
1388			}
1389			/* else Record is not in use, ignore it. */
1390		}
1391		put_dev_sector (sect);
1392		data = NULL;
1393	}
1394
1395	result = ldm_frag_commit (&frags, ldb);	/* Failures, already logged */
1396out:
1397	if (data)
1398		put_dev_sector (sect);
1399	ldm_frag_free (&frags);
1400
1401	return result;
1402}
1403
1404/**
1405 * ldm_free_vblks - Free a linked list of vblk's
1406 * @lh:  Head of a linked list of struct vblk
1407 *
1408 * Free a list of vblk's and free the memory used to maintain the list.
1409 *
1410 * Return:  none
1411 */
1412static void ldm_free_vblks (struct list_head *lh)
1413{
1414	struct list_head *item, *tmp;
1415
1416	BUG_ON (!lh);
1417
1418	list_for_each_safe (item, tmp, lh)
1419		kfree (list_entry (item, struct vblk, list));
1420}
1421
1422
1423/**
1424 * ldm_partition - Find out whether a device is a dynamic disk and handle it
1425 * @pp:    List of the partitions parsed so far
1426 * @bdev:  Device holding the LDM Database
1427 *
1428 * This determines whether the device @bdev is a dynamic disk and if so creates
1429 * the partitions necessary in the gendisk structure pointed to by @hd.
1430 *
1431 * We create a dummy device 1, which contains the LDM database, and then create
1432 * each partition described by the LDM database in sequence as devices 2+. For
1433 * example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
1434 * and so on: the actual data containing partitions.
1435 *
1436 * Return:  1 Success, @bdev is a dynamic disk and we handled it
1437 *          0 Success, @bdev is not a dynamic disk
1438 *         -1 An error occurred before enough information had been read
1439 *            Or @bdev is a dynamic disk, but it may be corrupted
1440 */
1441int ldm_partition (struct parsed_partitions *pp, struct block_device *bdev)
1442{
1443	struct ldmdb  *ldb;
1444	unsigned long base;
1445	int result = -1;
1446
1447	BUG_ON (!pp || !bdev);
1448
1449	/* Look for signs of a Dynamic Disk */
1450	if (!ldm_validate_partition_table (bdev))
1451		return 0;
1452
1453	ldb = kmalloc (sizeof (*ldb), GFP_KERNEL);
1454	if (!ldb) {
1455		ldm_crit ("Out of memory.");
1456		goto out;
1457	}
1458
1459	/* Parse and check privheads. */
1460	if (!ldm_validate_privheads (bdev, &ldb->ph))
1461		goto out;		/* Already logged */
1462
1463	/* All further references are relative to base (database start). */
1464	base = ldb->ph.config_start;
1465
1466	/* Parse and check tocs and vmdb. */
1467	if (!ldm_validate_tocblocks (bdev, base, ldb) ||
1468	    !ldm_validate_vmdb      (bdev, base, ldb))
1469	    	goto out;		/* Already logged */
1470
1471	/* Initialize vblk lists in ldmdb struct */
1472	INIT_LIST_HEAD (&ldb->v_dgrp);
1473	INIT_LIST_HEAD (&ldb->v_disk);
1474	INIT_LIST_HEAD (&ldb->v_volu);
1475	INIT_LIST_HEAD (&ldb->v_comp);
1476	INIT_LIST_HEAD (&ldb->v_part);
1477
1478	if (!ldm_get_vblks (bdev, base, ldb)) {
1479		ldm_crit ("Failed to read the VBLKs from the database.");
1480		goto cleanup;
1481	}
1482
1483	/* Finally, create the data partition devices. */
1484	if (ldm_create_data_partitions (pp, ldb)) {
1485		ldm_debug ("Parsed LDM database successfully.");
1486		result = 1;
1487	}
1488	/* else Already logged */
1489
1490cleanup:
1491	ldm_free_vblks (&ldb->v_dgrp);
1492	ldm_free_vblks (&ldb->v_disk);
1493	ldm_free_vblks (&ldb->v_volu);
1494	ldm_free_vblks (&ldb->v_comp);
1495	ldm_free_vblks (&ldb->v_part);
1496out:
1497	kfree (ldb);
1498	return result;
1499}
1500