1	// SPDX-License-Identifier: GPL-2.0-or-later
2	/*
3	* ldm - Support for Windows Logical Disk Manager (Dynamic Disks)
4	*
5	* Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
6	* Copyright (c) 2001-2012 Anton Altaparmakov
7	* Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
8	*
9	* Documentation is available at http://www.linux-ntfs.org/doku.php?id=downloads
10	*/
11
12	#include <linux/slab.h>
13	#include <linux/pagemap.h>
14	#include <linux/stringify.h>
15	#include <linux/kernel.h>
16	#include <linux/uuid.h>
17	#include <linux/msdos_partition.h>
18
19	#include "ldm.h"
20	#include "check.h"
21
22	/*
23	* ldm_debug/info/error/crit - Output an error message
24	* @f: A printf format string containing the message
25	* @...: Variables to substitute into @f
26	*
27	* ldm_debug() writes a DEBUG level message to the syslog but only if the
28	* driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
29	*/
30	#ifndef CONFIG_LDM_DEBUG
31	#define ldm_debug(...) do {} while (0)
32	#else
33	#define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __func__, f, ##a)
34	#endif
35
36	#define ldm_crit(f, a...) _ldm_printk (KERN_CRIT, __func__, f, ##a)
37	#define ldm_error(f, a...) _ldm_printk (KERN_ERR, __func__, f, ##a)
38	#define ldm_info(f, a...) _ldm_printk (KERN_INFO, __func__, f, ##a)
39
40	static __printf(3, 4)
41	void _ldm_printk(const char *level, const char *function, const char *fmt, ...)
42	{
43	struct va_format vaf;
44	va_list args;
45
46	va_start (args, fmt);
47
48	vaf.fmt = fmt;
49	vaf.va = &args;
50
51	printk("%s%s(): %pV\n", level, function, &vaf);
52
53	va_end(args);
54	}
55
56	/**
57	* ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
58	* @data: Raw database PRIVHEAD structure loaded from the device
59	* @ph: In-memory privhead structure in which to return parsed information
60	*
61	* This parses the LDM database PRIVHEAD structure supplied in @data and
62	* sets up the in-memory privhead structure @ph with the obtained information.
63	*
64	* Return: 'true' @ph contains the PRIVHEAD data
65	* 'false' @ph contents are undefined
66	*/
67	static bool ldm_parse_privhead(const u8 *data, struct privhead *ph)
68	{
69	bool is_vista = false;
70
71	BUG_ON(!data || !ph);
72	if (MAGIC_PRIVHEAD != get_unaligned_be64(p: data)) {
73	ldm_error("Cannot find PRIVHEAD structure. LDM database is"
74	" corrupt. Aborting.");
75	return false;
76	}
77	ph->ver_major = get_unaligned_be16(p: data + 0x000C);
78	ph->ver_minor = get_unaligned_be16(p: data + 0x000E);
79	ph->logical_disk_start = get_unaligned_be64(p: data + 0x011B);
80	ph->logical_disk_size = get_unaligned_be64(p: data + 0x0123);
81	ph->config_start = get_unaligned_be64(p: data + 0x012B);
82	ph->config_size = get_unaligned_be64(p: data + 0x0133);
83	/* Version 2.11 is Win2k/XP and version 2.12 is Vista. */
84	if (ph->ver_major == 2 && ph->ver_minor == 12)
85	is_vista = true;
86	if (!is_vista && (ph->ver_major != 2 || ph->ver_minor != 11)) {
87	ldm_error("Expected PRIVHEAD version 2.11 or 2.12, got %d.%d."
88	" Aborting.", ph->ver_major, ph->ver_minor);
89	return false;
90	}
91	ldm_debug("PRIVHEAD version %d.%d (Windows %s).", ph->ver_major,
92	ph->ver_minor, is_vista ? "Vista" : "2000/XP");
93	if (ph->config_size != LDM_DB_SIZE) { /* 1 MiB in sectors. */
94	/* Warn the user and continue, carefully. */
95	ldm_info("Database is normally %u bytes, it claims to "
96	"be %llu bytes.", LDM_DB_SIZE,
97	(unsigned long long)ph->config_size);
98	}
99	if ((ph->logical_disk_size == 0) || (ph->logical_disk_start +
100	ph->logical_disk_size > ph->config_start)) {
101	ldm_error("PRIVHEAD disk size doesn't match real disk size");
102	return false;
103	}
104	if (uuid_parse(uuid: data + 0x0030, u: &ph->disk_id)) {
105	ldm_error("PRIVHEAD contains an invalid GUID.");
106	return false;
107	}
108	ldm_debug("Parsed PRIVHEAD successfully.");
109	return true;
110	}
111
112	/**
113	* ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
114	* @data: Raw database TOCBLOCK structure loaded from the device
115	* @toc: In-memory toc structure in which to return parsed information
116	*
117	* This parses the LDM Database TOCBLOCK (table of contents) structure supplied
118	* in @data and sets up the in-memory tocblock structure @toc with the obtained
119	* information.
120	*
121	* N.B. The *_start and *_size values returned in @toc are not range-checked.
122	*
123	* Return: 'true' @toc contains the TOCBLOCK data
124	* 'false' @toc contents are undefined
125	*/
126	static bool ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
127	{
128	BUG_ON (!data || !toc);
129
130	if (MAGIC_TOCBLOCK != get_unaligned_be64(p: data)) {
131	ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
132	return false;
133	}
134	strncpy (p: toc->bitmap1_name, q: data + 0x24, size: sizeof (toc->bitmap1_name));
135	toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
136	toc->bitmap1_start = get_unaligned_be64(p: data + 0x2E);
137	toc->bitmap1_size = get_unaligned_be64(p: data + 0x36);
138
139	if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
140	sizeof (toc->bitmap1_name)) != 0) {
141	ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
142	TOC_BITMAP1, toc->bitmap1_name);
143	return false;
144	}
145	strncpy (p: toc->bitmap2_name, q: data + 0x46, size: sizeof (toc->bitmap2_name));
146	toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
147	toc->bitmap2_start = get_unaligned_be64(p: data + 0x50);
148	toc->bitmap2_size = get_unaligned_be64(p: data + 0x58);
149	if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
150	sizeof (toc->bitmap2_name)) != 0) {
151	ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
152	TOC_BITMAP2, toc->bitmap2_name);
153	return false;
154	}
155	ldm_debug ("Parsed TOCBLOCK successfully.");
156	return true;
157	}
158
159	/**
160	* ldm_parse_vmdb - Read the LDM Database VMDB structure
161	* @data: Raw database VMDB structure loaded from the device
162	* @vm: In-memory vmdb structure in which to return parsed information
163	*
164	* This parses the LDM Database VMDB structure supplied in @data and sets up
165	* the in-memory vmdb structure @vm with the obtained information.
166	*
167	* N.B. The *_start, *_size and *_seq values will be range-checked later.
168	*
169	* Return: 'true' @vm contains VMDB info
170	* 'false' @vm contents are undefined
171	*/
172	static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
173	{
174	BUG_ON (!data || !vm);
175
176	if (MAGIC_VMDB != get_unaligned_be32(p: data)) {
177	ldm_crit ("Cannot find the VMDB, database may be corrupt.");
178	return false;
179	}
180
181	vm->ver_major = get_unaligned_be16(p: data + 0x12);
182	vm->ver_minor = get_unaligned_be16(p: data + 0x14);
183	if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
184	ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
185	"Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
186	return false;
187	}
188
189	vm->vblk_size = get_unaligned_be32(p: data + 0x08);
190	if (vm->vblk_size == 0) {
191	ldm_error ("Illegal VBLK size");
192	return false;
193	}
194
195	vm->vblk_offset = get_unaligned_be32(p: data + 0x0C);
196	vm->last_vblk_seq = get_unaligned_be32(p: data + 0x04);
197
198	ldm_debug ("Parsed VMDB successfully.");
199	return true;
200	}
201
202	/**
203	* ldm_compare_privheads - Compare two privhead objects
204	* @ph1: First privhead
205	* @ph2: Second privhead
206	*
207	* This compares the two privhead structures @ph1 and @ph2.
208	*
209	* Return: 'true' Identical
210	* 'false' Different
211	*/
212	static bool ldm_compare_privheads (const struct privhead *ph1,
213	const struct privhead *ph2)
214	{
215	BUG_ON (!ph1 || !ph2);
216
217	return ((ph1->ver_major == ph2->ver_major) &&
218	(ph1->ver_minor == ph2->ver_minor) &&
219	(ph1->logical_disk_start == ph2->logical_disk_start) &&
220	(ph1->logical_disk_size == ph2->logical_disk_size) &&
221	(ph1->config_start == ph2->config_start) &&
222	(ph1->config_size == ph2->config_size) &&
223	uuid_equal(u1: &ph1->disk_id, u2: &ph2->disk_id));
224	}
225
226	/**
227	* ldm_compare_tocblocks - Compare two tocblock objects
228	* @toc1: First toc
229	* @toc2: Second toc
230	*
231	* This compares the two tocblock structures @toc1 and @toc2.
232	*
233	* Return: 'true' Identical
234	* 'false' Different
235	*/
236	static bool ldm_compare_tocblocks (const struct tocblock *toc1,
237	const struct tocblock *toc2)
238	{
239	BUG_ON (!toc1 || !toc2);
240
241	return ((toc1->bitmap1_start == toc2->bitmap1_start) &&
242	(toc1->bitmap1_size == toc2->bitmap1_size) &&
243	(toc1->bitmap2_start == toc2->bitmap2_start) &&
244	(toc1->bitmap2_size == toc2->bitmap2_size) &&
245	!strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
246	sizeof (toc1->bitmap1_name)) &&
247	!strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
248	sizeof (toc1->bitmap2_name)));
249	}
250
251	/**
252	* ldm_validate_privheads - Compare the primary privhead with its backups
253	* @state: Partition check state including device holding the LDM Database
254	* @ph1: Memory struct to fill with ph contents
255	*
256	* Read and compare all three privheads from disk.
257	*
258	* The privheads on disk show the size and location of the main disk area and
259	* the configuration area (the database). The values are range-checked against
260	* @hd, which contains the real size of the disk.
261	*
262	* Return: 'true' Success
263	* 'false' Error
264	*/
265	static bool ldm_validate_privheads(struct parsed_partitions *state,
266	struct privhead *ph1)
267	{
268	static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
269	struct privhead *ph[3] = { ph1 };
270	Sector sect;
271	u8 *data;
272	bool result = false;
273	long num_sects;
274	int i;
275
276	BUG_ON (!state || !ph1);
277
278	ph[1] = kmalloc (size: sizeof (*ph[1]), GFP_KERNEL);
279	ph[2] = kmalloc (size: sizeof (*ph[2]), GFP_KERNEL);
280	if (!ph[1] || !ph[2]) {
281	ldm_crit ("Out of memory.");
282	goto out;
283	}
284
285	/* off[1 & 2] are relative to ph[0]->config_start */
286	ph[0]->config_start = 0;
287
288	/* Read and parse privheads */
289	for (i = 0; i < 3; i++) {
290	data = read_part_sector(state, n: ph[0]->config_start + off[i],
291	p: &sect);
292	if (!data) {
293	ldm_crit ("Disk read failed.");
294	goto out;
295	}
296	result = ldm_parse_privhead (data, ph: ph[i]);
297	put_dev_sector (p: sect);
298	if (!result) {
299	ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
300	if (i < 2)
301	goto out; /* Already logged */
302	else
303	break; /* FIXME ignore for now, 3rd PH can fail on odd-sized disks */
304	}
305	}
306
307	num_sects = get_capacity(disk: state->disk);
308
309	if ((ph[0]->config_start > num_sects) ||
310	((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
311	ldm_crit ("Database extends beyond the end of the disk.");
312	goto out;
313	}
314
315	if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
316	((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
317	> ph[0]->config_start)) {
318	ldm_crit ("Disk and database overlap.");
319	goto out;
320	}
321
322	if (!ldm_compare_privheads (ph1: ph[0], ph2: ph[1])) {
323	ldm_crit ("Primary and backup PRIVHEADs don't match.");
324	goto out;
325	}
326	/* FIXME ignore this for now
327	if (!ldm_compare_privheads (ph[0], ph[2])) {
328	ldm_crit ("Primary and backup PRIVHEADs don't match.");
329	goto out;
330	}*/
331	ldm_debug ("Validated PRIVHEADs successfully.");
332	result = true;
333	out:
334	kfree (objp: ph[1]);
335	kfree (objp: ph[2]);
336	return result;
337	}
338
339	/**
340	* ldm_validate_tocblocks - Validate the table of contents and its backups
341	* @state: Partition check state including device holding the LDM Database
342	* @base: Offset, into @state->disk, of the database
343	* @ldb: Cache of the database structures
344	*
345	* Find and compare the four tables of contents of the LDM Database stored on
346	* @state->disk and return the parsed information into @toc1.
347	*
348	* The offsets and sizes of the configs are range-checked against a privhead.
349	*
350	* Return: 'true' @toc1 contains validated TOCBLOCK info
351	* 'false' @toc1 contents are undefined
352	*/
353	static bool ldm_validate_tocblocks(struct parsed_partitions *state,
354	unsigned long base, struct ldmdb *ldb)
355	{
356	static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
357	struct tocblock *tb[4];
358	struct privhead *ph;
359	Sector sect;
360	u8 *data;
361	int i, nr_tbs;
362	bool result = false;
363
364	BUG_ON(!state || !ldb);
365	ph = &ldb->ph;
366	tb[0] = &ldb->toc;
367	tb[1] = kmalloc_array(n: 3, size: sizeof(*tb[1]), GFP_KERNEL);
368	if (!tb[1]) {
369	ldm_crit("Out of memory.");
370	goto err;
371	}
372	tb[2] = (struct tocblock*)((u8*)tb[1] + sizeof(*tb[1]));
373	tb[3] = (struct tocblock*)((u8*)tb[2] + sizeof(*tb[2]));
374	/*
375	* Try to read and parse all four TOCBLOCKs.
376	*
377	* Windows Vista LDM v2.12 does not always have all four TOCBLOCKs so
378	* skip any that fail as long as we get at least one valid TOCBLOCK.
379	*/
380	for (nr_tbs = i = 0; i < 4; i++) {
381	data = read_part_sector(state, n: base + off[i], p: &sect);
382	if (!data) {
383	ldm_error("Disk read failed for TOCBLOCK %d.", i);
384	continue;
385	}
386	if (ldm_parse_tocblock(data, toc: tb[nr_tbs]))
387	nr_tbs++;
388	put_dev_sector(p: sect);
389	}
390	if (!nr_tbs) {
391	ldm_crit("Failed to find a valid TOCBLOCK.");
392	goto err;
393	}
394	/* Range check the TOCBLOCK against a privhead. */
395	if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
396	((tb[0]->bitmap2_start + tb[0]->bitmap2_size) >
397	ph->config_size)) {
398	ldm_crit("The bitmaps are out of range. Giving up.");
399	goto err;
400	}
401	/* Compare all loaded TOCBLOCKs. */
402	for (i = 1; i < nr_tbs; i++) {
403	if (!ldm_compare_tocblocks(toc1: tb[0], toc2: tb[i])) {
404	ldm_crit("TOCBLOCKs 0 and %d do not match.", i);
405	goto err;
406	}
407	}
408	ldm_debug("Validated %d TOCBLOCKs successfully.", nr_tbs);
409	result = true;
410	err:
411	kfree(objp: tb[1]);
412	return result;
413	}
414
415	/**
416	* ldm_validate_vmdb - Read the VMDB and validate it
417	* @state: Partition check state including device holding the LDM Database
418	* @base: Offset, into @bdev, of the database
419	* @ldb: Cache of the database structures
420	*
421	* Find the vmdb of the LDM Database stored on @bdev and return the parsed
422	* information in @ldb.
423	*
424	* Return: 'true' @ldb contains validated VBDB info
425	* 'false' @ldb contents are undefined
426	*/
427	static bool ldm_validate_vmdb(struct parsed_partitions *state,
428	unsigned long base, struct ldmdb *ldb)
429	{
430	Sector sect;
431	u8 *data;
432	bool result = false;
433	struct vmdb *vm;
434	struct tocblock *toc;
435
436	BUG_ON (!state || !ldb);
437
438	vm = &ldb->vm;
439	toc = &ldb->toc;
440
441	data = read_part_sector(state, n: base + OFF_VMDB, p: &sect);
442	if (!data) {
443	ldm_crit ("Disk read failed.");
444	return false;
445	}
446
447	if (!ldm_parse_vmdb (data, vm))
448	goto out; /* Already logged */
449
450	/* Are there uncommitted transactions? */
451	if (get_unaligned_be16(p: data + 0x10) != 0x01) {
452	ldm_crit ("Database is not in a consistent state. Aborting.");
453	goto out;
454	}
455
456	if (vm->vblk_offset != 512)
457	ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
458
459	/*
460	* The last_vblkd_seq can be before the end of the vmdb, just make sure
461	* it is not out of bounds.
462	*/
463	if ((vm->vblk_size * vm->last_vblk_seq) > (toc->bitmap1_size << 9)) {
464	ldm_crit ("VMDB exceeds allowed size specified by TOCBLOCK. "
465	"Database is corrupt. Aborting.");
466	goto out;
467	}
468
469	result = true;
470	out:
471	put_dev_sector (p: sect);
472	return result;
473	}
474
475
476	/**
477	* ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
478	* @state: Partition check state including device holding the LDM Database
479	*
480	* This function provides a weak test to decide whether the device is a dynamic
481	* disk or not. It looks for an MS-DOS-style partition table containing at
482	* least one partition of type 0x42 (formerly SFS, now used by Windows for
483	* dynamic disks).
484	*
485	* N.B. The only possible error can come from the read_part_sector and that is
486	* only likely to happen if the underlying device is strange. If that IS
487	* the case we should return zero to let someone else try.
488	*
489	* Return: 'true' @state->disk is a dynamic disk
490	* 'false' @state->disk is not a dynamic disk, or an error occurred
491	*/
492	static bool ldm_validate_partition_table(struct parsed_partitions *state)
493	{
494	Sector sect;
495	u8 *data;
496	struct msdos_partition *p;
497	int i;
498	bool result = false;
499
500	BUG_ON(!state);
501
502	data = read_part_sector(state, n: 0, p: &sect);
503	if (!data) {
504	ldm_info ("Disk read failed.");
505	return false;
506	}
507
508	if (*(__le16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC))
509	goto out;
510
511	p = (struct msdos_partition *)(data + 0x01BE);
512	for (i = 0; i < 4; i++, p++)
513	if (p->sys_ind == LDM_PARTITION) {
514	result = true;
515	break;
516	}
517
518	if (result)
519	ldm_debug ("Found W2K dynamic disk partition type.");
520
521	out:
522	put_dev_sector (p: sect);
523	return result;
524	}
525
526	/**
527	* ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
528	* @ldb: Cache of the database structures
529	*
530	* The LDM Database contains a list of all partitions on all dynamic disks.
531	* The primary PRIVHEAD, at the beginning of the physical disk, tells us
532	* the GUID of this disk. This function searches for the GUID in a linked
533	* list of vblk's.
534	*
535	* Return: Pointer, A matching vblk was found
536	* NULL, No match, or an error
537	*/
538	static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
539	{
540	struct list_head *item;
541
542	BUG_ON (!ldb);
543
544	list_for_each (item, &ldb->v_disk) {
545	struct vblk *v = list_entry (item, struct vblk, list);
546	if (uuid_equal(u1: &v->vblk.disk.disk_id, u2: &ldb->ph.disk_id))
547	return v;
548	}
549
550	return NULL;
551	}
552
553	/**
554	* ldm_create_data_partitions - Create data partitions for this device
555	* @pp: List of the partitions parsed so far
556	* @ldb: Cache of the database structures
557	*
558	* The database contains ALL the partitions for ALL disk groups, so we need to
559	* filter out this specific disk. Using the disk's object id, we can find all
560	* the partitions in the database that belong to this disk.
561	*
562	* Add each partition in our database, to the parsed_partitions structure.
563	*
564	* N.B. This function creates the partitions in the order it finds partition
565	* objects in the linked list.
566	*
567	* Return: 'true' Partition created
568	* 'false' Error, probably a range checking problem
569	*/
570	static bool ldm_create_data_partitions (struct parsed_partitions *pp,
571	const struct ldmdb *ldb)
572	{
573	struct list_head *item;
574	struct vblk *vb;
575	struct vblk *disk;
576	struct vblk_part *part;
577	int part_num = 1;
578
579	BUG_ON (!pp || !ldb);
580
581	disk = ldm_get_disk_objid (ldb);
582	if (!disk) {
583	ldm_crit ("Can't find the ID of this disk in the database.");
584	return false;
585	}
586
587	strlcat(p: pp->pp_buf, q: " [LDM]", PAGE_SIZE);
588
589	/* Create the data partitions */
590	list_for_each (item, &ldb->v_part) {
591	vb = list_entry (item, struct vblk, list);
592	part = &vb->vblk.part;
593
594	if (part->disk_id != disk->obj_id)
595	continue;
596
597	put_partition (p: pp, n: part_num, from: ldb->ph.logical_disk_start +
598	part->start, size: part->size);
599	part_num++;
600	}
601
602	strlcat(p: pp->pp_buf, q: "\n", PAGE_SIZE);
603	return true;
604	}
605
606
607	/**
608	* ldm_relative - Calculate the next relative offset
609	* @buffer: Block of data being worked on
610	* @buflen: Size of the block of data
611	* @base: Size of the previous fixed width fields
612	* @offset: Cumulative size of the previous variable-width fields
613	*
614	* Because many of the VBLK fields are variable-width, it's necessary
615	* to calculate each offset based on the previous one and the length
616	* of the field it pointed to.
617	*
618	* Return: -1 Error, the calculated offset exceeded the size of the buffer
619	* n OK, a range-checked offset into buffer
620	*/
621	static int ldm_relative(const u8 *buffer, int buflen, int base, int offset)
622	{
623
624	base += offset;
625	if (!buffer || offset < 0 || base > buflen) {
626	if (!buffer)
627	ldm_error("!buffer");
628	if (offset < 0)
629	ldm_error("offset (%d) < 0", offset);
630	if (base > buflen)
631	ldm_error("base (%d) > buflen (%d)", base, buflen);
632	return -1;
633	}
634	if (base + buffer[base] >= buflen) {
635	ldm_error("base (%d) + buffer[base] (%d) >= buflen (%d)", base,
636	buffer[base], buflen);
637	return -1;
638	}
639	return buffer[base] + offset + 1;
640	}
641
642	/**
643	* ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
644	* @block: Pointer to the variable-width number to convert
645	*
646	* Large numbers in the LDM Database are often stored in a packed format. Each
647	* number is prefixed by a one byte width marker. All numbers in the database
648	* are stored in big-endian byte order. This function reads one of these
649	* numbers and returns the result
650	*
651	* N.B. This function DOES NOT perform any range checking, though the most
652	* it will read is eight bytes.
653	*
654	* Return: n A number
655	* 0 Zero, or an error occurred
656	*/
657	static u64 ldm_get_vnum (const u8 *block)
658	{
659	u64 tmp = 0;
660	u8 length;
661
662	BUG_ON (!block);
663
664	length = *block++;
665
666	if (length && length <= 8)
667	while (length--)
668	tmp = (tmp << 8) | *block++;
669	else
670	ldm_error ("Illegal length %d.", length);
671
672	return tmp;
673	}
674
675	/**
676	* ldm_get_vstr - Read a length-prefixed string into a buffer
677	* @block: Pointer to the length marker
678	* @buffer: Location to copy string to
679	* @buflen: Size of the output buffer
680	*
681	* Many of the strings in the LDM Database are not NULL terminated. Instead
682	* they are prefixed by a one byte length marker. This function copies one of
683	* these strings into a buffer.
684	*
685	* N.B. This function DOES NOT perform any range checking on the input.
686	* If the buffer is too small, the output will be truncated.
687	*
688	* Return: 0, Error and @buffer contents are undefined
689	* n, String length in characters (excluding NULL)
690	* buflen-1, String was truncated.
691	*/
692	static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
693	{
694	int length;
695
696	BUG_ON (!block || !buffer);
697
698	length = block[0];
699	if (length >= buflen) {
700	ldm_error ("Truncating string %d -> %d.", length, buflen);
701	length = buflen - 1;
702	}
703	memcpy (buffer, block + 1, length);
704	buffer[length] = 0;
705	return length;
706	}
707
708
709	/**
710	* ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
711	* @buffer: Block of data being worked on
712	* @buflen: Size of the block of data
713	* @vb: In-memory vblk in which to return information
714	*
715	* Read a raw VBLK Component object (version 3) into a vblk structure.
716	*
717	* Return: 'true' @vb contains a Component VBLK
718	* 'false' @vb contents are not defined
719	*/
720	static bool ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
721	{
722	int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
723	struct vblk_comp *comp;
724
725	BUG_ON (!buffer || !vb);
726
727	r_objid = ldm_relative (buffer, buflen, base: 0x18, offset: 0);
728	r_name = ldm_relative (buffer, buflen, base: 0x18, offset: r_objid);
729	r_vstate = ldm_relative (buffer, buflen, base: 0x18, offset: r_name);
730	r_child = ldm_relative (buffer, buflen, base: 0x1D, offset: r_vstate);
731	r_parent = ldm_relative (buffer, buflen, base: 0x2D, offset: r_child);
732
733	if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
734	r_stripe = ldm_relative (buffer, buflen, base: 0x2E, offset: r_parent);
735	r_cols = ldm_relative (buffer, buflen, base: 0x2E, offset: r_stripe);
736	len = r_cols;
737	} else {
738	r_stripe = 0;
739	len = r_parent;
740	}
741	if (len < 0)
742	return false;
743
744	len += VBLK_SIZE_CMP3;
745	if (len != get_unaligned_be32(p: buffer + 0x14))
746	return false;
747
748	comp = &vb->vblk.comp;
749	ldm_get_vstr (block: buffer + 0x18 + r_name, buffer: comp->state,
750	buflen: sizeof (comp->state));
751	comp->type = buffer[0x18 + r_vstate];
752	comp->children = ldm_get_vnum (block: buffer + 0x1D + r_vstate);
753	comp->parent_id = ldm_get_vnum (block: buffer + 0x2D + r_child);
754	comp->chunksize = r_stripe ? ldm_get_vnum (block: buffer+r_parent+0x2E) : 0;
755
756	return true;
757	}
758
759	/**
760	* ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
761	* @buffer: Block of data being worked on
762	* @buflen: Size of the block of data
763	* @vb: In-memory vblk in which to return information
764	*
765	* Read a raw VBLK Disk Group object (version 3) into a vblk structure.
766	*
767	* Return: 'true' @vb contains a Disk Group VBLK
768	* 'false' @vb contents are not defined
769	*/
770	static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
771	{
772	int r_objid, r_name, r_diskid, r_id1, r_id2, len;
773	struct vblk_dgrp *dgrp;
774
775	BUG_ON (!buffer || !vb);
776
777	r_objid = ldm_relative (buffer, buflen, base: 0x18, offset: 0);
778	r_name = ldm_relative (buffer, buflen, base: 0x18, offset: r_objid);
779	r_diskid = ldm_relative (buffer, buflen, base: 0x18, offset: r_name);
780
781	if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
782	r_id1 = ldm_relative (buffer, buflen, base: 0x24, offset: r_diskid);
783	r_id2 = ldm_relative (buffer, buflen, base: 0x24, offset: r_id1);
784	len = r_id2;
785	} else
786	len = r_diskid;
787	if (len < 0)
788	return false;
789
790	len += VBLK_SIZE_DGR3;
791	if (len != get_unaligned_be32(p: buffer + 0x14))
792	return false;
793
794	dgrp = &vb->vblk.dgrp;
795	ldm_get_vstr (block: buffer + 0x18 + r_name, buffer: dgrp->disk_id,
796	buflen: sizeof (dgrp->disk_id));
797	return true;
798	}
799
800	/**
801	* ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
802	* @buffer: Block of data being worked on
803	* @buflen: Size of the block of data
804	* @vb: In-memory vblk in which to return information
805	*
806	* Read a raw VBLK Disk Group object (version 4) into a vblk structure.
807	*
808	* Return: 'true' @vb contains a Disk Group VBLK
809	* 'false' @vb contents are not defined
810	*/
811	static bool ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
812	{
813	char buf[64];
814	int r_objid, r_name, r_id1, r_id2, len;
815
816	BUG_ON (!buffer || !vb);
817
818	r_objid = ldm_relative (buffer, buflen, base: 0x18, offset: 0);
819	r_name = ldm_relative (buffer, buflen, base: 0x18, offset: r_objid);
820
821	if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
822	r_id1 = ldm_relative (buffer, buflen, base: 0x44, offset: r_name);
823	r_id2 = ldm_relative (buffer, buflen, base: 0x44, offset: r_id1);
824	len = r_id2;
825	} else
826	len = r_name;
827	if (len < 0)
828	return false;
829
830	len += VBLK_SIZE_DGR4;
831	if (len != get_unaligned_be32(p: buffer + 0x14))
832	return false;
833
834	ldm_get_vstr (block: buffer + 0x18 + r_objid, buffer: buf, buflen: sizeof (buf));
835	return true;
836	}
837
838	/**
839	* ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
840	* @buffer: Block of data being worked on
841	* @buflen: Size of the block of data
842	* @vb: In-memory vblk in which to return information
843	*
844	* Read a raw VBLK Disk object (version 3) into a vblk structure.
845	*
846	* Return: 'true' @vb contains a Disk VBLK
847	* 'false' @vb contents are not defined
848	*/
849	static bool ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
850	{
851	int r_objid, r_name, r_diskid, r_altname, len;
852	struct vblk_disk *disk;
853
854	BUG_ON (!buffer || !vb);
855
856	r_objid = ldm_relative (buffer, buflen, base: 0x18, offset: 0);
857	r_name = ldm_relative (buffer, buflen, base: 0x18, offset: r_objid);
858	r_diskid = ldm_relative (buffer, buflen, base: 0x18, offset: r_name);
859	r_altname = ldm_relative (buffer, buflen, base: 0x18, offset: r_diskid);
860	len = r_altname;
861	if (len < 0)
862	return false;
863
864	len += VBLK_SIZE_DSK3;
865	if (len != get_unaligned_be32(p: buffer + 0x14))
866	return false;
867
868	disk = &vb->vblk.disk;
869	ldm_get_vstr (block: buffer + 0x18 + r_diskid, buffer: disk->alt_name,
870	buflen: sizeof (disk->alt_name));
871	if (uuid_parse(uuid: buffer + 0x19 + r_name, u: &disk->disk_id))
872	return false;
873
874	return true;
875	}
876
877	/**
878	* ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
879	* @buffer: Block of data being worked on
880	* @buflen: Size of the block of data
881	* @vb: In-memory vblk in which to return information
882	*
883	* Read a raw VBLK Disk object (version 4) into a vblk structure.
884	*
885	* Return: 'true' @vb contains a Disk VBLK
886	* 'false' @vb contents are not defined
887	*/
888	static bool ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
889	{
890	int r_objid, r_name, len;
891	struct vblk_disk *disk;
892
893	BUG_ON (!buffer || !vb);
894
895	r_objid = ldm_relative (buffer, buflen, base: 0x18, offset: 0);
896	r_name = ldm_relative (buffer, buflen, base: 0x18, offset: r_objid);
897	len = r_name;
898	if (len < 0)
899	return false;
900
901	len += VBLK_SIZE_DSK4;
902	if (len != get_unaligned_be32(p: buffer + 0x14))
903	return false;
904
905	disk = &vb->vblk.disk;
906	import_uuid(dst: &disk->disk_id, src: buffer + 0x18 + r_name);
907	return true;
908	}
909
910	/**
911	* ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
912	* @buffer: Block of data being worked on
913	* @buflen: Size of the block of data
914	* @vb: In-memory vblk in which to return information
915	*
916	* Read a raw VBLK Partition object (version 3) into a vblk structure.
917	*
918	* Return: 'true' @vb contains a Partition VBLK
919	* 'false' @vb contents are not defined
920	*/
921	static bool ldm_parse_prt3(const u8 *buffer, int buflen, struct vblk *vb)
922	{
923	int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
924	struct vblk_part *part;
925
926	BUG_ON(!buffer || !vb);
927	r_objid = ldm_relative(buffer, buflen, base: 0x18, offset: 0);
928	if (r_objid < 0) {
929	ldm_error("r_objid %d < 0", r_objid);
930	return false;
931	}
932	r_name = ldm_relative(buffer, buflen, base: 0x18, offset: r_objid);
933	if (r_name < 0) {
934	ldm_error("r_name %d < 0", r_name);
935	return false;
936	}
937	r_size = ldm_relative(buffer, buflen, base: 0x34, offset: r_name);
938	if (r_size < 0) {
939	ldm_error("r_size %d < 0", r_size);
940	return false;
941	}
942	r_parent = ldm_relative(buffer, buflen, base: 0x34, offset: r_size);
943	if (r_parent < 0) {
944	ldm_error("r_parent %d < 0", r_parent);
945	return false;
946	}
947	r_diskid = ldm_relative(buffer, buflen, base: 0x34, offset: r_parent);
948	if (r_diskid < 0) {
949	ldm_error("r_diskid %d < 0", r_diskid);
950	return false;
951	}
952	if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
953	r_index = ldm_relative(buffer, buflen, base: 0x34, offset: r_diskid);
954	if (r_index < 0) {
955	ldm_error("r_index %d < 0", r_index);
956	return false;
957	}
958	len = r_index;
959	} else
960	len = r_diskid;
961	if (len < 0) {
962	ldm_error("len %d < 0", len);
963	return false;
964	}
965	len += VBLK_SIZE_PRT3;
966	if (len > get_unaligned_be32(p: buffer + 0x14)) {
967	ldm_error("len %d > BE32(buffer + 0x14) %d", len,
968	get_unaligned_be32(buffer + 0x14));
969	return false;
970	}
971	part = &vb->vblk.part;
972	part->start = get_unaligned_be64(p: buffer + 0x24 + r_name);
973	part->volume_offset = get_unaligned_be64(p: buffer + 0x2C + r_name);
974	part->size = ldm_get_vnum(block: buffer + 0x34 + r_name);
975	part->parent_id = ldm_get_vnum(block: buffer + 0x34 + r_size);
976	part->disk_id = ldm_get_vnum(block: buffer + 0x34 + r_parent);
977	if (vb->flags & VBLK_FLAG_PART_INDEX)
978	part->partnum = buffer[0x35 + r_diskid];
979	else
980	part->partnum = 0;
981	return true;
982	}
983
984	/**
985	* ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
986	* @buffer: Block of data being worked on
987	* @buflen: Size of the block of data
988	* @vb: In-memory vblk in which to return information
989	*
990	* Read a raw VBLK Volume object (version 5) into a vblk structure.
991	*
992	* Return: 'true' @vb contains a Volume VBLK
993	* 'false' @vb contents are not defined
994	*/
995	static bool ldm_parse_vol5(const u8 *buffer, int buflen, struct vblk *vb)
996	{
997	int r_objid, r_name, r_vtype, r_disable_drive_letter, r_child, r_size;
998	int r_id1, r_id2, r_size2, r_drive, len;
999	struct vblk_volu *volu;
1000
1001	BUG_ON(!buffer || !vb);
1002	r_objid = ldm_relative(buffer, buflen, base: 0x18, offset: 0);
1003	if (r_objid < 0) {
1004	ldm_error("r_objid %d < 0", r_objid);
1005	return false;
1006	}
1007	r_name = ldm_relative(buffer, buflen, base: 0x18, offset: r_objid);
1008	if (r_name < 0) {
1009	ldm_error("r_name %d < 0", r_name);
1010	return false;
1011	}
1012	r_vtype = ldm_relative(buffer, buflen, base: 0x18, offset: r_name);
1013	if (r_vtype < 0) {
1014	ldm_error("r_vtype %d < 0", r_vtype);
1015	return false;
1016	}
1017	r_disable_drive_letter = ldm_relative(buffer, buflen, base: 0x18, offset: r_vtype);
1018	if (r_disable_drive_letter < 0) {
1019	ldm_error("r_disable_drive_letter %d < 0",
1020	r_disable_drive_letter);
1021	return false;
1022	}
1023	r_child = ldm_relative(buffer, buflen, base: 0x2D, offset: r_disable_drive_letter);
1024	if (r_child < 0) {
1025	ldm_error("r_child %d < 0", r_child);
1026	return false;
1027	}
1028	r_size = ldm_relative(buffer, buflen, base: 0x3D, offset: r_child);
1029	if (r_size < 0) {
1030	ldm_error("r_size %d < 0", r_size);
1031	return false;
1032	}
1033	if (buffer[0x12] & VBLK_FLAG_VOLU_ID1) {
1034	r_id1 = ldm_relative(buffer, buflen, base: 0x52, offset: r_size);
1035	if (r_id1 < 0) {
1036	ldm_error("r_id1 %d < 0", r_id1);
1037	return false;
1038	}
1039	} else
1040	r_id1 = r_size;
1041	if (buffer[0x12] & VBLK_FLAG_VOLU_ID2) {
1042	r_id2 = ldm_relative(buffer, buflen, base: 0x52, offset: r_id1);
1043	if (r_id2 < 0) {
1044	ldm_error("r_id2 %d < 0", r_id2);
1045	return false;
1046	}
1047	} else
1048	r_id2 = r_id1;
1049	if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE) {
1050	r_size2 = ldm_relative(buffer, buflen, base: 0x52, offset: r_id2);
1051	if (r_size2 < 0) {
1052	ldm_error("r_size2 %d < 0", r_size2);
1053	return false;
1054	}
1055	} else
1056	r_size2 = r_id2;
1057	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1058	r_drive = ldm_relative(buffer, buflen, base: 0x52, offset: r_size2);
1059	if (r_drive < 0) {
1060	ldm_error("r_drive %d < 0", r_drive);
1061	return false;
1062	}
1063	} else
1064	r_drive = r_size2;
1065	len = r_drive;
1066	if (len < 0) {
1067	ldm_error("len %d < 0", len);
1068	return false;
1069	}
1070	len += VBLK_SIZE_VOL5;
1071	if (len > get_unaligned_be32(p: buffer + 0x14)) {
1072	ldm_error("len %d > BE32(buffer + 0x14) %d", len,
1073	get_unaligned_be32(buffer + 0x14));
1074	return false;
1075	}
1076	volu = &vb->vblk.volu;
1077	ldm_get_vstr(block: buffer + 0x18 + r_name, buffer: volu->volume_type,
1078	buflen: sizeof(volu->volume_type));
1079	memcpy(volu->volume_state, buffer + 0x18 + r_disable_drive_letter,
1080	sizeof(volu->volume_state));
1081	volu->size = ldm_get_vnum(block: buffer + 0x3D + r_child);
1082	volu->partition_type = buffer[0x41 + r_size];
1083	memcpy(volu->guid, buffer + 0x42 + r_size, sizeof(volu->guid));
1084	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
1085	ldm_get_vstr(block: buffer + 0x52 + r_size, buffer: volu->drive_hint,
1086	buflen: sizeof(volu->drive_hint));
1087	}
1088	return true;
1089	}
1090
1091	/**
1092	* ldm_parse_vblk - Read a raw VBLK object into a vblk structure
1093	* @buf: Block of data being worked on
1094	* @len: Size of the block of data
1095	* @vb: In-memory vblk in which to return information
1096	*
1097	* Read a raw VBLK object into a vblk structure. This function just reads the
1098	* information common to all VBLK types, then delegates the rest of the work to
1099	* helper functions: ldm_parse_*.
1100	*
1101	* Return: 'true' @vb contains a VBLK
1102	* 'false' @vb contents are not defined
1103	*/
1104	static bool ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
1105	{
1106	bool result = false;
1107	int r_objid;
1108
1109	BUG_ON (!buf || !vb);
1110
1111	r_objid = ldm_relative (buffer: buf, buflen: len, base: 0x18, offset: 0);
1112	if (r_objid < 0) {
1113	ldm_error ("VBLK header is corrupt.");
1114	return false;
1115	}
1116
1117	vb->flags = buf[0x12];
1118	vb->type = buf[0x13];
1119	vb->obj_id = ldm_get_vnum (block: buf + 0x18);
1120	ldm_get_vstr (block: buf+0x18+r_objid, buffer: vb->name, buflen: sizeof (vb->name));
1121
1122	switch (vb->type) {
1123	case VBLK_CMP3: result = ldm_parse_cmp3 (buffer: buf, buflen: len, vb); break;
1124	case VBLK_DSK3: result = ldm_parse_dsk3 (buffer: buf, buflen: len, vb); break;
1125	case VBLK_DSK4: result = ldm_parse_dsk4 (buffer: buf, buflen: len, vb); break;
1126	case VBLK_DGR3: result = ldm_parse_dgr3 (buffer: buf, buflen: len, vb); break;
1127	case VBLK_DGR4: result = ldm_parse_dgr4 (buffer: buf, buflen: len, vb); break;
1128	case VBLK_PRT3: result = ldm_parse_prt3 (buffer: buf, buflen: len, vb); break;
1129	case VBLK_VOL5: result = ldm_parse_vol5 (buffer: buf, buflen: len, vb); break;
1130	}
1131
1132	if (result)
1133	ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
1134	(unsigned long long) vb->obj_id, vb->type);
1135	else
1136	ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
1137	(unsigned long long) vb->obj_id, vb->type);
1138
1139	return result;
1140	}
1141
1142
1143	/**
1144	* ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
1145	* @data: Raw VBLK to add to the database
1146	* @len: Size of the raw VBLK
1147	* @ldb: Cache of the database structures
1148	*
1149	* The VBLKs are sorted into categories. Partitions are also sorted by offset.
1150	*
1151	* N.B. This function does not check the validity of the VBLKs.
1152	*
1153	* Return: 'true' The VBLK was added
1154	* 'false' An error occurred
1155	*/
1156	static bool ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
1157	{
1158	struct vblk *vb;
1159	struct list_head *item;
1160
1161	BUG_ON (!data || !ldb);
1162
1163	vb = kmalloc (size: sizeof (*vb), GFP_KERNEL);
1164	if (!vb) {
1165	ldm_crit ("Out of memory.");
1166	return false;
1167	}
1168
1169	if (!ldm_parse_vblk (buf: data, len, vb)) {
1170	kfree(objp: vb);
1171	return false; /* Already logged */
1172	}
1173
1174	/* Put vblk into the correct list. */
1175	switch (vb->type) {
1176	case VBLK_DGR3:
1177	case VBLK_DGR4:
1178	list_add (new: &vb->list, head: &ldb->v_dgrp);
1179	break;
1180	case VBLK_DSK3:
1181	case VBLK_DSK4:
1182	list_add (new: &vb->list, head: &ldb->v_disk);
1183	break;
1184	case VBLK_VOL5:
1185	list_add (new: &vb->list, head: &ldb->v_volu);
1186	break;
1187	case VBLK_CMP3:
1188	list_add (new: &vb->list, head: &ldb->v_comp);
1189	break;
1190	case VBLK_PRT3:
1191	/* Sort by the partition's start sector. */
1192	list_for_each (item, &ldb->v_part) {
1193	struct vblk *v = list_entry (item, struct vblk, list);
1194	if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
1195	(v->vblk.part.start > vb->vblk.part.start)) {
1196	list_add_tail (new: &vb->list, head: &v->list);
1197	return true;
1198	}
1199	}
1200	list_add_tail (new: &vb->list, head: &ldb->v_part);
1201	break;
1202	}
1203	return true;
1204	}
1205
1206	/**
1207	* ldm_frag_add - Add a VBLK fragment to a list
1208	* @data: Raw fragment to be added to the list
1209	* @size: Size of the raw fragment
1210	* @frags: Linked list of VBLK fragments
1211	*
1212	* Fragmented VBLKs may not be consecutive in the database, so they are placed
1213	* in a list so they can be pieced together later.
1214	*
1215	* Return: 'true' Success, the VBLK was added to the list
1216	* 'false' Error, a problem occurred
1217	*/
1218	static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
1219	{
1220	struct frag *f;
1221	struct list_head *item;
1222	int rec, num, group;
1223
1224	BUG_ON (!data || !frags);
1225
1226	if (size < 2 * VBLK_SIZE_HEAD) {
1227	ldm_error("Value of size is too small.");
1228	return false;
1229	}
1230
1231	group = get_unaligned_be32(p: data + 0x08);
1232	rec = get_unaligned_be16(p: data + 0x0C);
1233	num = get_unaligned_be16(p: data + 0x0E);
1234	if ((num < 1) || (num > 4)) {
1235	ldm_error ("A VBLK claims to have %d parts.", num);
1236	return false;
1237	}
1238	if (rec >= num) {
1239	ldm_error("REC value (%d) exceeds NUM value (%d)", rec, num);
1240	return false;
1241	}
1242
1243	list_for_each (item, frags) {
1244	f = list_entry (item, struct frag, list);
1245	if (f->group == group)
1246	goto found;
1247	}
1248
1249	f = kmalloc (size: sizeof (*f) + size*num, GFP_KERNEL);
1250	if (!f) {
1251	ldm_crit ("Out of memory.");
1252	return false;
1253	}
1254
1255	f->group = group;
1256	f->num = num;
1257	f->rec = rec;
1258	f->map = 0xFF << num;
1259
1260	list_add_tail (new: &f->list, head: frags);
1261	found:
1262	if (rec >= f->num) {
1263	ldm_error("REC value (%d) exceeds NUM value (%d)", rec, f->num);
1264	return false;
1265	}
1266	if (f->map & (1 << rec)) {
1267	ldm_error ("Duplicate VBLK, part %d.", rec);
1268	f->map &= 0x7F; /* Mark the group as broken */
1269	return false;
1270	}
1271	f->map |= (1 << rec);
1272	if (!rec)
1273	memcpy(f->data, data, VBLK_SIZE_HEAD);
1274	data += VBLK_SIZE_HEAD;
1275	size -= VBLK_SIZE_HEAD;
1276	memcpy(f->data + VBLK_SIZE_HEAD + rec * size, data, size);
1277	return true;
1278	}
1279
1280	/**
1281	* ldm_frag_free - Free a linked list of VBLK fragments
1282	* @list: Linked list of fragments
1283	*
1284	* Free a linked list of VBLK fragments
1285	*
1286	* Return: none
1287	*/
1288	static void ldm_frag_free (struct list_head *list)
1289	{
1290	struct list_head *item, *tmp;
1291
1292	BUG_ON (!list);
1293
1294	list_for_each_safe (item, tmp, list)
1295	kfree (list_entry (item, struct frag, list));
1296	}
1297
1298	/**
1299	* ldm_frag_commit - Validate fragmented VBLKs and add them to the database
1300	* @frags: Linked list of VBLK fragments
1301	* @ldb: Cache of the database structures
1302	*
1303	* Now that all the fragmented VBLKs have been collected, they must be added to
1304	* the database for later use.
1305	*
1306	* Return: 'true' All the fragments we added successfully
1307	* 'false' One or more of the fragments we invalid
1308	*/
1309	static bool ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
1310	{
1311	struct frag *f;
1312	struct list_head *item;
1313
1314	BUG_ON (!frags || !ldb);
1315
1316	list_for_each (item, frags) {
1317	f = list_entry (item, struct frag, list);
1318
1319	if (f->map != 0xFF) {
1320	ldm_error ("VBLK group %d is incomplete (0x%02x).",
1321	f->group, f->map);
1322	return false;
1323	}
1324
1325	if (!ldm_ldmdb_add (data: f->data, len: f->num*ldb->vm.vblk_size, ldb))
1326	return false; /* Already logged */
1327	}
1328	return true;
1329	}
1330
1331	/**
1332	* ldm_get_vblks - Read the on-disk database of VBLKs into memory
1333	* @state: Partition check state including device holding the LDM Database
1334	* @base: Offset, into @state->disk, of the database
1335	* @ldb: Cache of the database structures
1336	*
1337	* To use the information from the VBLKs, they need to be read from the disk,
1338	* unpacked and validated. We cache them in @ldb according to their type.
1339	*
1340	* Return: 'true' All the VBLKs were read successfully
1341	* 'false' An error occurred
1342	*/
1343	static bool ldm_get_vblks(struct parsed_partitions *state, unsigned long base,
1344	struct ldmdb *ldb)
1345	{
1346	int size, perbuf, skip, finish, s, v, recs;
1347	u8 *data = NULL;
1348	Sector sect;
1349	bool result = false;
1350	LIST_HEAD (frags);
1351
1352	BUG_ON(!state || !ldb);
1353
1354	size = ldb->vm.vblk_size;
1355	perbuf = 512 / size;
1356	skip = ldb->vm.vblk_offset >> 9; /* Bytes to sectors */
1357	finish = (size * ldb->vm.last_vblk_seq) >> 9;
1358
1359	for (s = skip; s < finish; s++) { /* For each sector */
1360	data = read_part_sector(state, n: base + OFF_VMDB + s, p: &sect);
1361	if (!data) {
1362	ldm_crit ("Disk read failed.");
1363	goto out;
1364	}
1365
1366	for (v = 0; v < perbuf; v++, data+=size) { /* For each vblk */
1367	if (MAGIC_VBLK != get_unaligned_be32(p: data)) {
1368	ldm_error ("Expected to find a VBLK.");
1369	goto out;
1370	}
1371
1372	recs = get_unaligned_be16(p: data + 0x0E); /* Number of records */
1373	if (recs == 1) {
1374	if (!ldm_ldmdb_add (data, len: size, ldb))
1375	goto out; /* Already logged */
1376	} else if (recs > 1) {
1377	if (!ldm_frag_add (data, size, frags: &frags))
1378	goto out; /* Already logged */
1379	}
1380	/* else Record is not in use, ignore it. */
1381	}
1382	put_dev_sector (p: sect);
1383	data = NULL;
1384	}
1385
1386	result = ldm_frag_commit (frags: &frags, ldb); /* Failures, already logged */
1387	out:
1388	if (data)
1389	put_dev_sector (p: sect);
1390	ldm_frag_free (list: &frags);
1391
1392	return result;
1393	}
1394
1395	/**
1396	* ldm_free_vblks - Free a linked list of vblk's
1397	* @lh: Head of a linked list of struct vblk
1398	*
1399	* Free a list of vblk's and free the memory used to maintain the list.
1400	*
1401	* Return: none
1402	*/
1403	static void ldm_free_vblks (struct list_head *lh)
1404	{
1405	struct list_head *item, *tmp;
1406
1407	BUG_ON (!lh);
1408
1409	list_for_each_safe (item, tmp, lh)
1410	kfree (list_entry (item, struct vblk, list));
1411	}
1412
1413
1414	/**
1415	* ldm_partition - Find out whether a device is a dynamic disk and handle it
1416	* @state: Partition check state including device holding the LDM Database
1417	*
1418	* This determines whether the device @bdev is a dynamic disk and if so creates
1419	* the partitions necessary in the gendisk structure pointed to by @hd.
1420	*
1421	* We create a dummy device 1, which contains the LDM database, and then create
1422	* each partition described by the LDM database in sequence as devices 2+. For
1423	* example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
1424	* and so on: the actual data containing partitions.
1425	*
1426	* Return: 1 Success, @state->disk is a dynamic disk and we handled it
1427	* 0 Success, @state->disk is not a dynamic disk
1428	* -1 An error occurred before enough information had been read
1429	* Or @state->disk is a dynamic disk, but it may be corrupted
1430	*/
1431	int ldm_partition(struct parsed_partitions *state)
1432	{
1433	struct ldmdb *ldb;
1434	unsigned long base;
1435	int result = -1;
1436
1437	BUG_ON(!state);
1438
1439	/* Look for signs of a Dynamic Disk */
1440	if (!ldm_validate_partition_table(state))
1441	return 0;
1442
1443	ldb = kmalloc (size: sizeof (*ldb), GFP_KERNEL);
1444	if (!ldb) {
1445	ldm_crit ("Out of memory.");
1446	goto out;
1447	}
1448
1449	/* Parse and check privheads. */
1450	if (!ldm_validate_privheads(state, ph1: &ldb->ph))
1451	goto out; /* Already logged */
1452
1453	/* All further references are relative to base (database start). */
1454	base = ldb->ph.config_start;
1455
1456	/* Parse and check tocs and vmdb. */
1457	if (!ldm_validate_tocblocks(state, base, ldb) ||
1458	!ldm_validate_vmdb(state, base, ldb))
1459	goto out; /* Already logged */
1460
1461	/* Initialize vblk lists in ldmdb struct */
1462	INIT_LIST_HEAD (list: &ldb->v_dgrp);
1463	INIT_LIST_HEAD (list: &ldb->v_disk);
1464	INIT_LIST_HEAD (list: &ldb->v_volu);
1465	INIT_LIST_HEAD (list: &ldb->v_comp);
1466	INIT_LIST_HEAD (list: &ldb->v_part);
1467
1468	if (!ldm_get_vblks(state, base, ldb)) {
1469	ldm_crit ("Failed to read the VBLKs from the database.");
1470	goto cleanup;
1471	}
1472
1473	/* Finally, create the data partition devices. */
1474	if (ldm_create_data_partitions(pp: state, ldb)) {
1475	ldm_debug ("Parsed LDM database successfully.");
1476	result = 1;
1477	}
1478	/* else Already logged */
1479
1480	cleanup:
1481	ldm_free_vblks (lh: &ldb->v_dgrp);
1482	ldm_free_vblks (lh: &ldb->v_disk);
1483	ldm_free_vblks (lh: &ldb->v_volu);
1484	ldm_free_vblks (lh: &ldb->v_comp);
1485	ldm_free_vblks (lh: &ldb->v_part);
1486	out:
1487	kfree (objp: ldb);
1488	return result;
1489	}
1490