Initial import

1 files changed, 1567 insertions, 0 deletions

diff --git a/block/partitions/ldm.c b/block/partitions/ldm.c
new file mode 100644
index 000000000..e507cfbd0
--- /dev/null
+++ b/block/partitions/ldm.c
@@ -0,0 +1,1567 @@
+/**
+ * ldm - Support for Windows Logical Disk Manager (Dynamic Disks)
+ *
+ * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org>
+ * Copyright (c) 2001-2012 Anton Altaparmakov
+ * Copyright (C) 2001,2002 Jakob Kemi <jakob.kemi@telia.com>
+ *
+ * Documentation is available at http://www.linux-ntfs.org/doku.php?id=downloads 
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 2 of the License, or (at your option) any later
+ * version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program (in the main directory of the source in the file COPYING); if
+ * not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+ * Boston, MA  02111-1307  USA
+ */
+
+#include <linux/slab.h>
+#include <linux/pagemap.h>
+#include <linux/stringify.h>
+#include <linux/kernel.h>
+#include "ldm.h"
+#include "check.h"
+#include "msdos.h"
+
+/**
+ * ldm_debug/info/error/crit - Output an error message
+ * @f:    A printf format string containing the message
+ * @...:  Variables to substitute into @f
+ *
+ * ldm_debug() writes a DEBUG level message to the syslog but only if the
+ * driver was compiled with debug enabled. Otherwise, the call turns into a NOP.
+ */
+#ifndef CONFIG_LDM_DEBUG
+#define ldm_debug(...)	do {} while (0)
+#else
+#define ldm_debug(f, a...) _ldm_printk (KERN_DEBUG, __func__, f, ##a)
+#endif
+
+#define ldm_crit(f, a...)  _ldm_printk (KERN_CRIT,  __func__, f, ##a)
+#define ldm_error(f, a...) _ldm_printk (KERN_ERR,   __func__, f, ##a)
+#define ldm_info(f, a...)  _ldm_printk (KERN_INFO,  __func__, f, ##a)
+
+static __printf(3, 4)
+void _ldm_printk(const char *level, const char *function, const char *fmt, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start (args, fmt);
+
+	vaf.fmt = fmt;
+	vaf.va = &args;
+
+	printk("%s%s(): %pV\n", level, function, &vaf);
+
+	va_end(args);
+}
+
+/**
+ * ldm_parse_hexbyte - Convert a ASCII hex number to a byte
+ * @src:  Pointer to at least 2 characters to convert.
+ *
+ * Convert a two character ASCII hex string to a number.
+ *
+ * Return:  0-255  Success, the byte was parsed correctly
+ *          -1     Error, an invalid character was supplied
+ */
+static int ldm_parse_hexbyte (const u8 *src)
+{
+	unsigned int x;		/* For correct wrapping */
+	int h;
+
+	/* high part */
+	x = h = hex_to_bin(src[0]);
+	if (h < 0)
+		return -1;
+
+	/* low part */
+	h = hex_to_bin(src[1]);
+	if (h < 0)
+		return -1;
+
+	return (x << 4) + h;
+}
+
+/**
+ * ldm_parse_guid - Convert GUID from ASCII to binary
+ * @src:   36 char string of the form fa50ff2b-f2e8-45de-83fa-65417f2f49ba
+ * @dest:  Memory block to hold binary GUID (16 bytes)
+ *
+ * N.B. The GUID need not be NULL terminated.
+ *
+ * Return:  'true'   @dest contains binary GUID
+ *          'false'  @dest contents are undefined
+ */
+static bool ldm_parse_guid (const u8 *src, u8 *dest)
+{
+	static const int size[] = { 4, 2, 2, 2, 6 };
+	int i, j, v;
+
+	if (src[8]  != '-' || src[13] != '-' ||
+	    src[18] != '-' || src[23] != '-')
+		return false;
+
+	for (j = 0; j < 5; j++, src++)
+		for (i = 0; i < size[j]; i++, src+=2, *dest++ = v)
+			if ((v = ldm_parse_hexbyte (src)) < 0)
+				return false;
+
+	return true;
+}
+
+/**
+ * ldm_parse_privhead - Read the LDM Database PRIVHEAD structure
+ * @data:  Raw database PRIVHEAD structure loaded from the device
+ * @ph:    In-memory privhead structure in which to return parsed information
+ *
+ * This parses the LDM database PRIVHEAD structure supplied in @data and
+ * sets up the in-memory privhead structure @ph with the obtained information.
+ *
+ * Return:  'true'   @ph contains the PRIVHEAD data
+ *          'false'  @ph contents are undefined
+ */
+static bool ldm_parse_privhead(const u8 *data, struct privhead *ph)
+{
+	bool is_vista = false;
+
+	BUG_ON(!data || !ph);
+	if (MAGIC_PRIVHEAD != get_unaligned_be64(data)) {
+		ldm_error("Cannot find PRIVHEAD structure. LDM database is"
+			" corrupt. Aborting.");
+		return false;
+	}
+	ph->ver_major = get_unaligned_be16(data + 0x000C);
+	ph->ver_minor = get_unaligned_be16(data + 0x000E);
+	ph->logical_disk_start = get_unaligned_be64(data + 0x011B);
+	ph->logical_disk_size = get_unaligned_be64(data + 0x0123);
+	ph->config_start = get_unaligned_be64(data + 0x012B);
+	ph->config_size = get_unaligned_be64(data + 0x0133);
+	/* Version 2.11 is Win2k/XP and version 2.12 is Vista. */
+	if (ph->ver_major == 2 && ph->ver_minor == 12)
+		is_vista = true;
+	if (!is_vista && (ph->ver_major != 2 || ph->ver_minor != 11)) {
+		ldm_error("Expected PRIVHEAD version 2.11 or 2.12, got %d.%d."
+			" Aborting.", ph->ver_major, ph->ver_minor);
+		return false;
+	}
+	ldm_debug("PRIVHEAD version %d.%d (Windows %s).", ph->ver_major,
+			ph->ver_minor, is_vista ? "Vista" : "2000/XP");
+	if (ph->config_size != LDM_DB_SIZE) {	/* 1 MiB in sectors. */
+		/* Warn the user and continue, carefully. */
+		ldm_info("Database is normally %u bytes, it claims to "
+			"be %llu bytes.", LDM_DB_SIZE,
+			(unsigned long long)ph->config_size);
+	}
+	if ((ph->logical_disk_size == 0) || (ph->logical_disk_start +
+			ph->logical_disk_size > ph->config_start)) {
+		ldm_error("PRIVHEAD disk size doesn't match real disk size");
+		return false;
+	}
+	if (!ldm_parse_guid(data + 0x0030, ph->disk_id)) {
+		ldm_error("PRIVHEAD contains an invalid GUID.");
+		return false;
+	}
+	ldm_debug("Parsed PRIVHEAD successfully.");
+	return true;
+}
+
+/**
+ * ldm_parse_tocblock - Read the LDM Database TOCBLOCK structure
+ * @data:  Raw database TOCBLOCK structure loaded from the device
+ * @toc:   In-memory toc structure in which to return parsed information
+ *
+ * This parses the LDM Database TOCBLOCK (table of contents) structure supplied
+ * in @data and sets up the in-memory tocblock structure @toc with the obtained
+ * information.
+ *
+ * N.B.  The *_start and *_size values returned in @toc are not range-checked.
+ *
+ * Return:  'true'   @toc contains the TOCBLOCK data
+ *          'false'  @toc contents are undefined
+ */
+static bool ldm_parse_tocblock (const u8 *data, struct tocblock *toc)
+{
+	BUG_ON (!data || !toc);
+
+	if (MAGIC_TOCBLOCK != get_unaligned_be64(data)) {
+		ldm_crit ("Cannot find TOCBLOCK, database may be corrupt.");
+		return false;
+	}
+	strncpy (toc->bitmap1_name, data + 0x24, sizeof (toc->bitmap1_name));
+	toc->bitmap1_name[sizeof (toc->bitmap1_name) - 1] = 0;
+	toc->bitmap1_start = get_unaligned_be64(data + 0x2E);
+	toc->bitmap1_size  = get_unaligned_be64(data + 0x36);
+
+	if (strncmp (toc->bitmap1_name, TOC_BITMAP1,
+			sizeof (toc->bitmap1_name)) != 0) {
+		ldm_crit ("TOCBLOCK's first bitmap is '%s', should be '%s'.",
+				TOC_BITMAP1, toc->bitmap1_name);
+		return false;
+	}
+	strncpy (toc->bitmap2_name, data + 0x46, sizeof (toc->bitmap2_name));
+	toc->bitmap2_name[sizeof (toc->bitmap2_name) - 1] = 0;
+	toc->bitmap2_start = get_unaligned_be64(data + 0x50);
+	toc->bitmap2_size  = get_unaligned_be64(data + 0x58);
+	if (strncmp (toc->bitmap2_name, TOC_BITMAP2,
+			sizeof (toc->bitmap2_name)) != 0) {
+		ldm_crit ("TOCBLOCK's second bitmap is '%s', should be '%s'.",
+				TOC_BITMAP2, toc->bitmap2_name);
+		return false;
+	}
+	ldm_debug ("Parsed TOCBLOCK successfully.");
+	return true;
+}
+
+/**
+ * ldm_parse_vmdb - Read the LDM Database VMDB structure
+ * @data:  Raw database VMDB structure loaded from the device
+ * @vm:    In-memory vmdb structure in which to return parsed information
+ *
+ * This parses the LDM Database VMDB structure supplied in @data and sets up
+ * the in-memory vmdb structure @vm with the obtained information.
+ *
+ * N.B.  The *_start, *_size and *_seq values will be range-checked later.
+ *
+ * Return:  'true'   @vm contains VMDB info
+ *          'false'  @vm contents are undefined
+ */
+static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
+{
+	BUG_ON (!data || !vm);
+
+	if (MAGIC_VMDB != get_unaligned_be32(data)) {
+		ldm_crit ("Cannot find the VMDB, database may be corrupt.");
+		return false;
+	}
+
+	vm->ver_major = get_unaligned_be16(data + 0x12);
+	vm->ver_minor = get_unaligned_be16(data + 0x14);
+	if ((vm->ver_major != 4) || (vm->ver_minor != 10)) {
+		ldm_error ("Expected VMDB version %d.%d, got %d.%d. "
+			"Aborting.", 4, 10, vm->ver_major, vm->ver_minor);
+		return false;
+	}
+
+	vm->vblk_size     = get_unaligned_be32(data + 0x08);
+	if (vm->vblk_size == 0) {
+		ldm_error ("Illegal VBLK size");
+		return false;
+	}
+
+	vm->vblk_offset   = get_unaligned_be32(data + 0x0C);
+	vm->last_vblk_seq = get_unaligned_be32(data + 0x04);
+
+	ldm_debug ("Parsed VMDB successfully.");
+	return true;
+}
+
+/**
+ * ldm_compare_privheads - Compare two privhead objects
+ * @ph1:  First privhead
+ * @ph2:  Second privhead
+ *
+ * This compares the two privhead structures @ph1 and @ph2.
+ *
+ * Return:  'true'   Identical
+ *          'false'  Different
+ */
+static bool ldm_compare_privheads (const struct privhead *ph1,
+				   const struct privhead *ph2)
+{
+	BUG_ON (!ph1 || !ph2);
+
+	return ((ph1->ver_major          == ph2->ver_major)		&&
+		(ph1->ver_minor          == ph2->ver_minor)		&&
+		(ph1->logical_disk_start == ph2->logical_disk_start)	&&
+		(ph1->logical_disk_size  == ph2->logical_disk_size)	&&
+		(ph1->config_start       == ph2->config_start)		&&
+		(ph1->config_size        == ph2->config_size)		&&
+		!memcmp (ph1->disk_id, ph2->disk_id, GUID_SIZE));
+}
+
+/**
+ * ldm_compare_tocblocks - Compare two tocblock objects
+ * @toc1:  First toc
+ * @toc2:  Second toc
+ *
+ * This compares the two tocblock structures @toc1 and @toc2.
+ *
+ * Return:  'true'   Identical
+ *          'false'  Different
+ */
+static bool ldm_compare_tocblocks (const struct tocblock *toc1,
+				   const struct tocblock *toc2)
+{
+	BUG_ON (!toc1 || !toc2);
+
+	return ((toc1->bitmap1_start == toc2->bitmap1_start)	&&
+		(toc1->bitmap1_size  == toc2->bitmap1_size)	&&
+		(toc1->bitmap2_start == toc2->bitmap2_start)	&&
+		(toc1->bitmap2_size  == toc2->bitmap2_size)	&&
+		!strncmp (toc1->bitmap1_name, toc2->bitmap1_name,
+			sizeof (toc1->bitmap1_name))		&&
+		!strncmp (toc1->bitmap2_name, toc2->bitmap2_name,
+			sizeof (toc1->bitmap2_name)));
+}
+
+/**
+ * ldm_validate_privheads - Compare the primary privhead with its backups
+ * @state: Partition check state including device holding the LDM Database
+ * @ph1:   Memory struct to fill with ph contents
+ *
+ * Read and compare all three privheads from disk.
+ *
+ * The privheads on disk show the size and location of the main disk area and
+ * the configuration area (the database).  The values are range-checked against
+ * @hd, which contains the real size of the disk.
+ *
+ * Return:  'true'   Success
+ *          'false'  Error
+ */
+static bool ldm_validate_privheads(struct parsed_partitions *state,
+				   struct privhead *ph1)
+{
+	static const int off[3] = { OFF_PRIV1, OFF_PRIV2, OFF_PRIV3 };
+	struct privhead *ph[3] = { ph1 };
+	Sector sect;
+	u8 *data;
+	bool result = false;
+	long num_sects;
+	int i;
+
+	BUG_ON (!state || !ph1);
+
+	ph[1] = kmalloc (sizeof (*ph[1]), GFP_KERNEL);
+	ph[2] = kmalloc (sizeof (*ph[2]), GFP_KERNEL);
+	if (!ph[1] || !ph[2]) {
+		ldm_crit ("Out of memory.");
+		goto out;
+	}
+
+	/* off[1 & 2] are relative to ph[0]->config_start */
+	ph[0]->config_start = 0;
+
+	/* Read and parse privheads */
+	for (i = 0; i < 3; i++) {
+		data = read_part_sector(state, ph[0]->config_start + off[i],
+					&sect);
+		if (!data) {
+			ldm_crit ("Disk read failed.");
+			goto out;
+		}
+		result = ldm_parse_privhead (data, ph[i]);
+		put_dev_sector (sect);
+		if (!result) {
+			ldm_error ("Cannot find PRIVHEAD %d.", i+1); /* Log again */
+			if (i < 2)
+				goto out;	/* Already logged */
+			else
+				break;	/* FIXME ignore for now, 3rd PH can fail on odd-sized disks */
+		}
+	}
+
+	num_sects = state->bdev->bd_inode->i_size >> 9;
+
+	if ((ph[0]->config_start > num_sects) ||
+	   ((ph[0]->config_start + ph[0]->config_size) > num_sects)) {
+		ldm_crit ("Database extends beyond the end of the disk.");
+		goto out;
+	}
+
+	if ((ph[0]->logical_disk_start > ph[0]->config_start) ||
+	   ((ph[0]->logical_disk_start + ph[0]->logical_disk_size)
+		    > ph[0]->config_start)) {
+		ldm_crit ("Disk and database overlap.");
+		goto out;
+	}
+
+	if (!ldm_compare_privheads (ph[0], ph[1])) {
+		ldm_crit ("Primary and backup PRIVHEADs don't match.");
+		goto out;
+	}
+	/* FIXME ignore this for now
+	if (!ldm_compare_privheads (ph[0], ph[2])) {
+		ldm_crit ("Primary and backup PRIVHEADs don't match.");
+		goto out;
+	}*/
+	ldm_debug ("Validated PRIVHEADs successfully.");
+	result = true;
+out:
+	kfree (ph[1]);
+	kfree (ph[2]);
+	return result;
+}
+
+/**
+ * ldm_validate_tocblocks - Validate the table of contents and its backups
+ * @state: Partition check state including device holding the LDM Database
+ * @base:  Offset, into @state->bdev, of the database
+ * @ldb:   Cache of the database structures
+ *
+ * Find and compare the four tables of contents of the LDM Database stored on
+ * @state->bdev and return the parsed information into @toc1.
+ *
+ * The offsets and sizes of the configs are range-checked against a privhead.
+ *
+ * Return:  'true'   @toc1 contains validated TOCBLOCK info
+ *          'false'  @toc1 contents are undefined
+ */
+static bool ldm_validate_tocblocks(struct parsed_partitions *state,
+				   unsigned long base, struct ldmdb *ldb)
+{
+	static const int off[4] = { OFF_TOCB1, OFF_TOCB2, OFF_TOCB3, OFF_TOCB4};
+	struct tocblock *tb[4];
+	struct privhead *ph;
+	Sector sect;
+	u8 *data;
+	int i, nr_tbs;
+	bool result = false;
+
+	BUG_ON(!state || !ldb);
+	ph = &ldb->ph;
+	tb[0] = &ldb->toc;
+	tb[1] = kmalloc(sizeof(*tb[1]) * 3, GFP_KERNEL);
+	if (!tb[1]) {
+		ldm_crit("Out of memory.");
+		goto err;
+	}
+	tb[2] = (struct tocblock*)((u8*)tb[1] + sizeof(*tb[1]));
+	tb[3] = (struct tocblock*)((u8*)tb[2] + sizeof(*tb[2]));
+	/*
+	 * Try to read and parse all four TOCBLOCKs.
+	 *
+	 * Windows Vista LDM v2.12 does not always have all four TOCBLOCKs so
+	 * skip any that fail as long as we get at least one valid TOCBLOCK.
+	 */
+	for (nr_tbs = i = 0; i < 4; i++) {
+		data = read_part_sector(state, base + off[i], &sect);
+		if (!data) {
+			ldm_error("Disk read failed for TOCBLOCK %d.", i);
+			continue;
+		}
+		if (ldm_parse_tocblock(data, tb[nr_tbs]))
+			nr_tbs++;
+		put_dev_sector(sect);
+	}
+	if (!nr_tbs) {
+		ldm_crit("Failed to find a valid TOCBLOCK.");
+		goto err;
+	}
+	/* Range check the TOCBLOCK against a privhead. */
+	if (((tb[0]->bitmap1_start + tb[0]->bitmap1_size) > ph->config_size) ||
+			((tb[0]->bitmap2_start + tb[0]->bitmap2_size) >
+			ph->config_size)) {
+		ldm_crit("The bitmaps are out of range.  Giving up.");
+		goto err;
+	}
+	/* Compare all loaded TOCBLOCKs. */
+	for (i = 1; i < nr_tbs; i++) {
+		if (!ldm_compare_tocblocks(tb[0], tb[i])) {
+			ldm_crit("TOCBLOCKs 0 and %d do not match.", i);
+			goto err;
+		}
+	}
+	ldm_debug("Validated %d TOCBLOCKs successfully.", nr_tbs);
+	result = true;
+err:
+	kfree(tb[1]);
+	return result;
+}
+
+/**
+ * ldm_validate_vmdb - Read the VMDB and validate it
+ * @state: Partition check state including device holding the LDM Database
+ * @base:  Offset, into @bdev, of the database
+ * @ldb:   Cache of the database structures
+ *
+ * Find the vmdb of the LDM Database stored on @bdev and return the parsed
+ * information in @ldb.
+ *
+ * Return:  'true'   @ldb contains validated VBDB info
+ *          'false'  @ldb contents are undefined
+ */
+static bool ldm_validate_vmdb(struct parsed_partitions *state,
+			      unsigned long base, struct ldmdb *ldb)
+{
+	Sector sect;
+	u8 *data;
+	bool result = false;
+	struct vmdb *vm;
+	struct tocblock *toc;
+
+	BUG_ON (!state || !ldb);
+
+	vm  = &ldb->vm;
+	toc = &ldb->toc;
+
+	data = read_part_sector(state, base + OFF_VMDB, &sect);
+	if (!data) {
+		ldm_crit ("Disk read failed.");
+		return false;
+	}
+
+	if (!ldm_parse_vmdb (data, vm))
+		goto out;				/* Already logged */
+
+	/* Are there uncommitted transactions? */
+	if (get_unaligned_be16(data + 0x10) != 0x01) {
+		ldm_crit ("Database is not in a consistent state.  Aborting.");
+		goto out;
+	}
+
+	if (vm->vblk_offset != 512)
+		ldm_info ("VBLKs start at offset 0x%04x.", vm->vblk_offset);
+
+	/*
+	 * The last_vblkd_seq can be before the end of the vmdb, just make sure
+	 * it is not out of bounds.
+	 */
+	if ((vm->vblk_size * vm->last_vblk_seq) > (toc->bitmap1_size << 9)) {
+		ldm_crit ("VMDB exceeds allowed size specified by TOCBLOCK.  "
+				"Database is corrupt.  Aborting.");
+		goto out;
+	}
+
+	result = true;
+out:
+	put_dev_sector (sect);
+	return result;
+}
+
+
+/**
+ * ldm_validate_partition_table - Determine whether bdev might be a dynamic disk
+ * @state: Partition check state including device holding the LDM Database
+ *
+ * This function provides a weak test to decide whether the device is a dynamic
+ * disk or not.  It looks for an MS-DOS-style partition table containing at
+ * least one partition of type 0x42 (formerly SFS, now used by Windows for
+ * dynamic disks).
+ *
+ * N.B.  The only possible error can come from the read_part_sector and that is
+ *       only likely to happen if the underlying device is strange.  If that IS
+ *       the case we should return zero to let someone else try.
+ *
+ * Return:  'true'   @state->bdev is a dynamic disk
+ *          'false'  @state->bdev is not a dynamic disk, or an error occurred
+ */
+static bool ldm_validate_partition_table(struct parsed_partitions *state)
+{
+	Sector sect;
+	u8 *data;
+	struct partition *p;
+	int i;
+	bool result = false;
+
+	BUG_ON(!state);
+
+	data = read_part_sector(state, 0, &sect);
+	if (!data) {
+		ldm_info ("Disk read failed.");
+		return false;
+	}
+
+	if (*(__le16*) (data + 0x01FE) != cpu_to_le16 (MSDOS_LABEL_MAGIC))
+		goto out;
+
+	p = (struct partition*)(data + 0x01BE);
+	for (i = 0; i < 4; i++, p++)
+		if (SYS_IND (p) == LDM_PARTITION) {
+			result = true;
+			break;
+		}
+
+	if (result)
+		ldm_debug ("Found W2K dynamic disk partition type.");
+
+out:
+	put_dev_sector (sect);
+	return result;
+}
+
+/**
+ * ldm_get_disk_objid - Search a linked list of vblk's for a given Disk Id
+ * @ldb:  Cache of the database structures
+ *
+ * The LDM Database contains a list of all partitions on all dynamic disks.
+ * The primary PRIVHEAD, at the beginning of the physical disk, tells us
+ * the GUID of this disk.  This function searches for the GUID in a linked
+ * list of vblk's.
+ *
+ * Return:  Pointer, A matching vblk was found
+ *          NULL,    No match, or an error
+ */
+static struct vblk * ldm_get_disk_objid (const struct ldmdb *ldb)
+{
+	struct list_head *item;
+
+	BUG_ON (!ldb);
+
+	list_for_each (item, &ldb->v_disk) {
+		struct vblk *v = list_entry (item, struct vblk, list);
+		if (!memcmp (v->vblk.disk.disk_id, ldb->ph.disk_id, GUID_SIZE))
+			return v;
+	}
+
+	return NULL;
+}
+
+/**
+ * ldm_create_data_partitions - Create data partitions for this device
+ * @pp:   List of the partitions parsed so far
+ * @ldb:  Cache of the database structures
+ *
+ * The database contains ALL the partitions for ALL disk groups, so we need to
+ * filter out this specific disk. Using the disk's object id, we can find all
+ * the partitions in the database that belong to this disk.
+ *
+ * Add each partition in our database, to the parsed_partitions structure.
+ *
+ * N.B.  This function creates the partitions in the order it finds partition
+ *       objects in the linked list.
+ *
+ * Return:  'true'   Partition created
+ *          'false'  Error, probably a range checking problem
+ */
+static bool ldm_create_data_partitions (struct parsed_partitions *pp,
+					const struct ldmdb *ldb)
+{
+	struct list_head *item;
+	struct vblk *vb;
+	struct vblk *disk;
+	struct vblk_part *part;
+	int part_num = 1;
+
+	BUG_ON (!pp || !ldb);
+
+	disk = ldm_get_disk_objid (ldb);
+	if (!disk) {
+		ldm_crit ("Can't find the ID of this disk in the database.");
+		return false;
+	}
+
+	strlcat(pp->pp_buf, " [LDM]", PAGE_SIZE);
+
+	/* Create the data partitions */
+	list_for_each (item, &ldb->v_part) {
+		vb = list_entry (item, struct vblk, list);
+		part = &vb->vblk.part;
+
+		if (part->disk_id != disk->obj_id)
+			continue;
+
+		put_partition (pp, part_num, ldb->ph.logical_disk_start +
+				part->start, part->size);
+		part_num++;
+	}
+
+	strlcat(pp->pp_buf, "\n", PAGE_SIZE);
+	return true;
+}
+
+
+/**
+ * ldm_relative - Calculate the next relative offset
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @base:    Size of the previous fixed width fields
+ * @offset:  Cumulative size of the previous variable-width fields
+ *
+ * Because many of the VBLK fields are variable-width, it's necessary
+ * to calculate each offset based on the previous one and the length
+ * of the field it pointed to.
+ *
+ * Return:  -1 Error, the calculated offset exceeded the size of the buffer
+ *           n OK, a range-checked offset into buffer
+ */
+static int ldm_relative(const u8 *buffer, int buflen, int base, int offset)
+{
+
+	base += offset;
+	if (!buffer || offset < 0 || base > buflen) {
+		if (!buffer)
+			ldm_error("!buffer");
+		if (offset < 0)
+			ldm_error("offset (%d) < 0", offset);
+		if (base > buflen)
+			ldm_error("base (%d) > buflen (%d)", base, buflen);
+		return -1;
+	}
+	if (base + buffer[base] >= buflen) {
+		ldm_error("base (%d) + buffer[base] (%d) >= buflen (%d)", base,
+				buffer[base], buflen);
+		return -1;
+	}
+	return buffer[base] + offset + 1;
+}
+
+/**
+ * ldm_get_vnum - Convert a variable-width, big endian number, into cpu order
+ * @block:  Pointer to the variable-width number to convert
+ *
+ * Large numbers in the LDM Database are often stored in a packed format.  Each
+ * number is prefixed by a one byte width marker.  All numbers in the database
+ * are stored in big-endian byte order.  This function reads one of these
+ * numbers and returns the result
+ *
+ * N.B.  This function DOES NOT perform any range checking, though the most
+ *       it will read is eight bytes.
+ *
+ * Return:  n A number
+ *          0 Zero, or an error occurred
+ */
+static u64 ldm_get_vnum (const u8 *block)
+{
+	u64 tmp = 0;
+	u8 length;
+
+	BUG_ON (!block);
+
+	length = *block++;
+
+	if (length && length <= 8)
+		while (length--)
+			tmp = (tmp << 8) | *block++;
+	else
+		ldm_error ("Illegal length %d.", length);
+
+	return tmp;
+}
+
+/**
+ * ldm_get_vstr - Read a length-prefixed string into a buffer
+ * @block:   Pointer to the length marker
+ * @buffer:  Location to copy string to
+ * @buflen:  Size of the output buffer
+ *
+ * Many of the strings in the LDM Database are not NULL terminated.  Instead
+ * they are prefixed by a one byte length marker.  This function copies one of
+ * these strings into a buffer.
+ *
+ * N.B.  This function DOES NOT perform any range checking on the input.
+ *       If the buffer is too small, the output will be truncated.
+ *
+ * Return:  0, Error and @buffer contents are undefined
+ *          n, String length in characters (excluding NULL)
+ *          buflen-1, String was truncated.
+ */
+static int ldm_get_vstr (const u8 *block, u8 *buffer, int buflen)
+{
+	int length;
+
+	BUG_ON (!block || !buffer);
+
+	length = block[0];
+	if (length >= buflen) {
+		ldm_error ("Truncating string %d -> %d.", length, buflen);
+		length = buflen - 1;
+	}
+	memcpy (buffer, block + 1, length);
+	buffer[length] = 0;
+	return length;
+}
+
+
+/**
+ * ldm_parse_cmp3 - Read a raw VBLK Component object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Component object (version 3) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Component VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_cmp3 (const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, r_vstate, r_child, r_parent, r_stripe, r_cols, len;
+	struct vblk_comp *comp;
+
+	BUG_ON (!buffer || !vb);
+
+	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
+	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
+	r_vstate = ldm_relative (buffer, buflen, 0x18, r_name);
+	r_child  = ldm_relative (buffer, buflen, 0x1D, r_vstate);
+	r_parent = ldm_relative (buffer, buflen, 0x2D, r_child);
+
+	if (buffer[0x12] & VBLK_FLAG_COMP_STRIPE) {
+		r_stripe = ldm_relative (buffer, buflen, 0x2E, r_parent);
+		r_cols   = ldm_relative (buffer, buflen, 0x2E, r_stripe);
+		len = r_cols;
+	} else {
+		r_stripe = 0;
+		r_cols   = 0;
+		len = r_parent;
+	}
+	if (len < 0)
+		return false;
+
+	len += VBLK_SIZE_CMP3;
+	if (len != get_unaligned_be32(buffer + 0x14))
+		return false;
+
+	comp = &vb->vblk.comp;
+	ldm_get_vstr (buffer + 0x18 + r_name, comp->state,
+		sizeof (comp->state));
+	comp->type      = buffer[0x18 + r_vstate];
+	comp->children  = ldm_get_vnum (buffer + 0x1D + r_vstate);
+	comp->parent_id = ldm_get_vnum (buffer + 0x2D + r_child);
+	comp->chunksize = r_stripe ? ldm_get_vnum (buffer+r_parent+0x2E) : 0;
+
+	return true;
+}
+
+/**
+ * ldm_parse_dgr3 - Read a raw VBLK Disk Group object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Disk Group object (version 3) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Disk Group VBLK
+ *          'false'  @vb contents are not defined
+ */
+static int ldm_parse_dgr3 (const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, r_diskid, r_id1, r_id2, len;
+	struct vblk_dgrp *dgrp;
+
+	BUG_ON (!buffer || !vb);
+
+	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
+	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
+	r_diskid = ldm_relative (buffer, buflen, 0x18, r_name);
+
+	if (buffer[0x12] & VBLK_FLAG_DGR3_IDS) {
+		r_id1 = ldm_relative (buffer, buflen, 0x24, r_diskid);
+		r_id2 = ldm_relative (buffer, buflen, 0x24, r_id1);
+		len = r_id2;
+	} else {
+		r_id1 = 0;
+		r_id2 = 0;
+		len = r_diskid;
+	}
+	if (len < 0)
+		return false;
+
+	len += VBLK_SIZE_DGR3;
+	if (len != get_unaligned_be32(buffer + 0x14))
+		return false;
+
+	dgrp = &vb->vblk.dgrp;
+	ldm_get_vstr (buffer + 0x18 + r_name, dgrp->disk_id,
+		sizeof (dgrp->disk_id));
+	return true;
+}
+
+/**
+ * ldm_parse_dgr4 - Read a raw VBLK Disk Group object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Disk Group object (version 4) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Disk Group VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_dgr4 (const u8 *buffer, int buflen, struct vblk *vb)
+{
+	char buf[64];
+	int r_objid, r_name, r_id1, r_id2, len;
+	struct vblk_dgrp *dgrp;
+
+	BUG_ON (!buffer || !vb);
+
+	r_objid  = ldm_relative (buffer, buflen, 0x18, 0);
+	r_name   = ldm_relative (buffer, buflen, 0x18, r_objid);
+
+	if (buffer[0x12] & VBLK_FLAG_DGR4_IDS) {
+		r_id1 = ldm_relative (buffer, buflen, 0x44, r_name);
+		r_id2 = ldm_relative (buffer, buflen, 0x44, r_id1);
+		len = r_id2;
+	} else {
+		r_id1 = 0;
+		r_id2 = 0;
+		len = r_name;
+	}
+	if (len < 0)
+		return false;
+
+	len += VBLK_SIZE_DGR4;
+	if (len != get_unaligned_be32(buffer + 0x14))
+		return false;
+
+	dgrp = &vb->vblk.dgrp;
+
+	ldm_get_vstr (buffer + 0x18 + r_objid, buf, sizeof (buf));
+	return true;
+}
+
+/**
+ * ldm_parse_dsk3 - Read a raw VBLK Disk object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Disk object (version 3) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Disk VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_dsk3 (const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, r_diskid, r_altname, len;
+	struct vblk_disk *disk;
+
+	BUG_ON (!buffer || !vb);
+
+	r_objid   = ldm_relative (buffer, buflen, 0x18, 0);
+	r_name    = ldm_relative (buffer, buflen, 0x18, r_objid);
+	r_diskid  = ldm_relative (buffer, buflen, 0x18, r_name);
+	r_altname = ldm_relative (buffer, buflen, 0x18, r_diskid);
+	len = r_altname;
+	if (len < 0)
+		return false;
+
+	len += VBLK_SIZE_DSK3;
+	if (len != get_unaligned_be32(buffer + 0x14))
+		return false;
+
+	disk = &vb->vblk.disk;
+	ldm_get_vstr (buffer + 0x18 + r_diskid, disk->alt_name,
+		sizeof (disk->alt_name));
+	if (!ldm_parse_guid (buffer + 0x19 + r_name, disk->disk_id))
+		return false;
+
+	return true;
+}
+
+/**
+ * ldm_parse_dsk4 - Read a raw VBLK Disk object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Disk object (version 4) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Disk VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_dsk4 (const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, len;
+	struct vblk_disk *disk;
+
+	BUG_ON (!buffer || !vb);
+
+	r_objid = ldm_relative (buffer, buflen, 0x18, 0);
+	r_name  = ldm_relative (buffer, buflen, 0x18, r_objid);
+	len     = r_name;
+	if (len < 0)
+		return false;
+
+	len += VBLK_SIZE_DSK4;
+	if (len != get_unaligned_be32(buffer + 0x14))
+		return false;
+
+	disk = &vb->vblk.disk;
+	memcpy (disk->disk_id, buffer + 0x18 + r_name, GUID_SIZE);
+	return true;
+}
+
+/**
+ * ldm_parse_prt3 - Read a raw VBLK Partition object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Partition object (version 3) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Partition VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_prt3(const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, r_size, r_parent, r_diskid, r_index, len;
+	struct vblk_part *part;
+
+	BUG_ON(!buffer || !vb);
+	r_objid = ldm_relative(buffer, buflen, 0x18, 0);
+	if (r_objid < 0) {
+		ldm_error("r_objid %d < 0", r_objid);
+		return false;
+	}
+	r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
+	if (r_name < 0) {
+		ldm_error("r_name %d < 0", r_name);
+		return false;
+	}
+	r_size = ldm_relative(buffer, buflen, 0x34, r_name);
+	if (r_size < 0) {
+		ldm_error("r_size %d < 0", r_size);
+		return false;
+	}
+	r_parent = ldm_relative(buffer, buflen, 0x34, r_size);
+	if (r_parent < 0) {
+		ldm_error("r_parent %d < 0", r_parent);
+		return false;
+	}
+	r_diskid = ldm_relative(buffer, buflen, 0x34, r_parent);
+	if (r_diskid < 0) {
+		ldm_error("r_diskid %d < 0", r_diskid);
+		return false;
+	}
+	if (buffer[0x12] & VBLK_FLAG_PART_INDEX) {
+		r_index = ldm_relative(buffer, buflen, 0x34, r_diskid);
+		if (r_index < 0) {
+			ldm_error("r_index %d < 0", r_index);
+			return false;
+		}
+		len = r_index;
+	} else {
+		r_index = 0;
+		len = r_diskid;
+	}
+	if (len < 0) {
+		ldm_error("len %d < 0", len);
+		return false;
+	}
+	len += VBLK_SIZE_PRT3;
+	if (len > get_unaligned_be32(buffer + 0x14)) {
+		ldm_error("len %d > BE32(buffer + 0x14) %d", len,
+				get_unaligned_be32(buffer + 0x14));
+		return false;
+	}
+	part = &vb->vblk.part;
+	part->start = get_unaligned_be64(buffer + 0x24 + r_name);
+	part->volume_offset = get_unaligned_be64(buffer + 0x2C + r_name);
+	part->size = ldm_get_vnum(buffer + 0x34 + r_name);
+	part->parent_id = ldm_get_vnum(buffer + 0x34 + r_size);
+	part->disk_id = ldm_get_vnum(buffer + 0x34 + r_parent);
+	if (vb->flags & VBLK_FLAG_PART_INDEX)
+		part->partnum = buffer[0x35 + r_diskid];
+	else
+		part->partnum = 0;
+	return true;
+}
+
+/**
+ * ldm_parse_vol5 - Read a raw VBLK Volume object into a vblk structure
+ * @buffer:  Block of data being worked on
+ * @buflen:  Size of the block of data
+ * @vb:      In-memory vblk in which to return information
+ *
+ * Read a raw VBLK Volume object (version 5) into a vblk structure.
+ *
+ * Return:  'true'   @vb contains a Volume VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_vol5(const u8 *buffer, int buflen, struct vblk *vb)
+{
+	int r_objid, r_name, r_vtype, r_disable_drive_letter, r_child, r_size;
+	int r_id1, r_id2, r_size2, r_drive, len;
+	struct vblk_volu *volu;
+
+	BUG_ON(!buffer || !vb);
+	r_objid = ldm_relative(buffer, buflen, 0x18, 0);
+	if (r_objid < 0) {
+		ldm_error("r_objid %d < 0", r_objid);
+		return false;
+	}
+	r_name = ldm_relative(buffer, buflen, 0x18, r_objid);
+	if (r_name < 0) {
+		ldm_error("r_name %d < 0", r_name);
+		return false;
+	}
+	r_vtype = ldm_relative(buffer, buflen, 0x18, r_name);
+	if (r_vtype < 0) {
+		ldm_error("r_vtype %d < 0", r_vtype);
+		return false;
+	}
+	r_disable_drive_letter = ldm_relative(buffer, buflen, 0x18, r_vtype);
+	if (r_disable_drive_letter < 0) {
+		ldm_error("r_disable_drive_letter %d < 0",
+				r_disable_drive_letter);
+		return false;
+	}
+	r_child = ldm_relative(buffer, buflen, 0x2D, r_disable_drive_letter);
+	if (r_child < 0) {
+		ldm_error("r_child %d < 0", r_child);
+		return false;
+	}
+	r_size = ldm_relative(buffer, buflen, 0x3D, r_child);
+	if (r_size < 0) {
+		ldm_error("r_size %d < 0", r_size);
+		return false;
+	}
+	if (buffer[0x12] & VBLK_FLAG_VOLU_ID1) {
+		r_id1 = ldm_relative(buffer, buflen, 0x52, r_size);
+		if (r_id1 < 0) {
+			ldm_error("r_id1 %d < 0", r_id1);
+			return false;
+		}
+	} else
+		r_id1 = r_size;
+	if (buffer[0x12] & VBLK_FLAG_VOLU_ID2) {
+		r_id2 = ldm_relative(buffer, buflen, 0x52, r_id1);
+		if (r_id2 < 0) {
+			ldm_error("r_id2 %d < 0", r_id2);
+			return false;
+		}
+	} else
+		r_id2 = r_id1;
+	if (buffer[0x12] & VBLK_FLAG_VOLU_SIZE) {
+		r_size2 = ldm_relative(buffer, buflen, 0x52, r_id2);
+		if (r_size2 < 0) {
+			ldm_error("r_size2 %d < 0", r_size2);
+			return false;
+		}
+	} else
+		r_size2 = r_id2;
+	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
+		r_drive = ldm_relative(buffer, buflen, 0x52, r_size2);
+		if (r_drive < 0) {
+			ldm_error("r_drive %d < 0", r_drive);
+			return false;
+		}
+	} else
+		r_drive = r_size2;
+	len = r_drive;
+	if (len < 0) {
+		ldm_error("len %d < 0", len);
+		return false;
+	}
+	len += VBLK_SIZE_VOL5;
+	if (len > get_unaligned_be32(buffer + 0x14)) {
+		ldm_error("len %d > BE32(buffer + 0x14) %d", len,
+				get_unaligned_be32(buffer + 0x14));
+		return false;
+	}
+	volu = &vb->vblk.volu;
+	ldm_get_vstr(buffer + 0x18 + r_name, volu->volume_type,
+			sizeof(volu->volume_type));
+	memcpy(volu->volume_state, buffer + 0x18 + r_disable_drive_letter,
+			sizeof(volu->volume_state));
+	volu->size = ldm_get_vnum(buffer + 0x3D + r_child);
+	volu->partition_type = buffer[0x41 + r_size];
+	memcpy(volu->guid, buffer + 0x42 + r_size, sizeof(volu->guid));
+	if (buffer[0x12] & VBLK_FLAG_VOLU_DRIVE) {
+		ldm_get_vstr(buffer + 0x52 + r_size, volu->drive_hint,
+				sizeof(volu->drive_hint));
+	}
+	return true;
+}
+
+/**
+ * ldm_parse_vblk - Read a raw VBLK object into a vblk structure
+ * @buf:  Block of data being worked on
+ * @len:  Size of the block of data
+ * @vb:   In-memory vblk in which to return information
+ *
+ * Read a raw VBLK object into a vblk structure.  This function just reads the
+ * information common to all VBLK types, then delegates the rest of the work to
+ * helper functions: ldm_parse_*.
+ *
+ * Return:  'true'   @vb contains a VBLK
+ *          'false'  @vb contents are not defined
+ */
+static bool ldm_parse_vblk (const u8 *buf, int len, struct vblk *vb)
+{
+	bool result = false;
+	int r_objid;
+
+	BUG_ON (!buf || !vb);
+
+	r_objid = ldm_relative (buf, len, 0x18, 0);
+	if (r_objid < 0) {
+		ldm_error ("VBLK header is corrupt.");
+		return false;
+	}
+
+	vb->flags  = buf[0x12];
+	vb->type   = buf[0x13];
+	vb->obj_id = ldm_get_vnum (buf + 0x18);
+	ldm_get_vstr (buf+0x18+r_objid, vb->name, sizeof (vb->name));
+
+	switch (vb->type) {
+		case VBLK_CMP3:  result = ldm_parse_cmp3 (buf, len, vb); break;
+		case VBLK_DSK3:  result = ldm_parse_dsk3 (buf, len, vb); break;
+		case VBLK_DSK4:  result = ldm_parse_dsk4 (buf, len, vb); break;
+		case VBLK_DGR3:  result = ldm_parse_dgr3 (buf, len, vb); break;
+		case VBLK_DGR4:  result = ldm_parse_dgr4 (buf, len, vb); break;
+		case VBLK_PRT3:  result = ldm_parse_prt3 (buf, len, vb); break;
+		case VBLK_VOL5:  result = ldm_parse_vol5 (buf, len, vb); break;
+	}
+
+	if (result)
+		ldm_debug ("Parsed VBLK 0x%llx (type: 0x%02x) ok.",
+			 (unsigned long long) vb->obj_id, vb->type);
+	else
+		ldm_error ("Failed to parse VBLK 0x%llx (type: 0x%02x).",
+			(unsigned long long) vb->obj_id, vb->type);
+
+	return result;
+}
+
+
+/**
+ * ldm_ldmdb_add - Adds a raw VBLK entry to the ldmdb database
+ * @data:  Raw VBLK to add to the database
+ * @len:   Size of the raw VBLK
+ * @ldb:   Cache of the database structures
+ *
+ * The VBLKs are sorted into categories.  Partitions are also sorted by offset.
+ *
+ * N.B.  This function does not check the validity of the VBLKs.
+ *
+ * Return:  'true'   The VBLK was added
+ *          'false'  An error occurred
+ */
+static bool ldm_ldmdb_add (u8 *data, int len, struct ldmdb *ldb)
+{
+	struct vblk *vb;
+	struct list_head *item;
+
+	BUG_ON (!data || !ldb);
+
+	vb = kmalloc (sizeof (*vb), GFP_KERNEL);
+	if (!vb) {
+		ldm_crit ("Out of memory.");
+		return false;
+	}
+
+	if (!ldm_parse_vblk (data, len, vb)) {
+		kfree(vb);
+		return false;			/* Already logged */
+	}
+
+	/* Put vblk into the correct list. */
+	switch (vb->type) {
+	case VBLK_DGR3:
+	case VBLK_DGR4:
+		list_add (&vb->list, &ldb->v_dgrp);
+		break;
+	case VBLK_DSK3:
+	case VBLK_DSK4:
+		list_add (&vb->list, &ldb->v_disk);
+		break;
+	case VBLK_VOL5:
+		list_add (&vb->list, &ldb->v_volu);
+		break;
+	case VBLK_CMP3:
+		list_add (&vb->list, &ldb->v_comp);
+		break;
+	case VBLK_PRT3:
+		/* Sort by the partition's start sector. */
+		list_for_each (item, &ldb->v_part) {
+			struct vblk *v = list_entry (item, struct vblk, list);
+			if ((v->vblk.part.disk_id == vb->vblk.part.disk_id) &&
+			    (v->vblk.part.start > vb->vblk.part.start)) {
+				list_add_tail (&vb->list, &v->list);
+				return true;
+			}
+		}
+		list_add_tail (&vb->list, &ldb->v_part);
+		break;
+	}
+	return true;
+}
+
+/**
+ * ldm_frag_add - Add a VBLK fragment to a list
+ * @data:   Raw fragment to be added to the list
+ * @size:   Size of the raw fragment
+ * @frags:  Linked list of VBLK fragments
+ *
+ * Fragmented VBLKs may not be consecutive in the database, so they are placed
+ * in a list so they can be pieced together later.
+ *
+ * Return:  'true'   Success, the VBLK was added to the list
+ *          'false'  Error, a problem occurred
+ */
+static bool ldm_frag_add (const u8 *data, int size, struct list_head *frags)
+{
+	struct frag *f;
+	struct list_head *item;
+	int rec, num, group;
+
+	BUG_ON (!data || !frags);
+
+	if (size < 2 * VBLK_SIZE_HEAD) {
+		ldm_error("Value of size is to small.");
+		return false;
+	}
+
+	group = get_unaligned_be32(data + 0x08);
+	rec   = get_unaligned_be16(data + 0x0C);
+	num   = get_unaligned_be16(data + 0x0E);
+	if ((num < 1) || (num > 4)) {
+		ldm_error ("A VBLK claims to have %d parts.", num);
+		return false;
+	}
+	if (rec >= num) {
+		ldm_error("REC value (%d) exceeds NUM value (%d)", rec, num);
+		return false;
+	}
+
+	list_for_each (item, frags) {
+		f = list_entry (item, struct frag, list);
+		if (f->group == group)
+			goto found;
+	}
+
+	f = kmalloc (sizeof (*f) + size*num, GFP_KERNEL);
+	if (!f) {
+		ldm_crit ("Out of memory.");
+		return false;
+	}
+
+	f->group = group;
+	f->num   = num;
+	f->rec   = rec;
+	f->map   = 0xFF << num;
+
+	list_add_tail (&f->list, frags);
+found:
+	if (rec >= f->num) {
+		ldm_error("REC value (%d) exceeds NUM value (%d)", rec, f->num);
+		return false;
+	}
+	if (f->map & (1 << rec)) {
+		ldm_error ("Duplicate VBLK, part %d.", rec);
+		f->map &= 0x7F;			/* Mark the group as broken */
+		return false;
+	}
+	f->map |= (1 << rec);
+	if (!rec)
+		memcpy(f->data, data, VBLK_SIZE_HEAD);
+	data += VBLK_SIZE_HEAD;
+	size -= VBLK_SIZE_HEAD;
+	memcpy(f->data + VBLK_SIZE_HEAD + rec * size, data, size);
+	return true;
+}
+
+/**
+ * ldm_frag_free - Free a linked list of VBLK fragments
+ * @list:  Linked list of fragments
+ *
+ * Free a linked list of VBLK fragments
+ *
+ * Return:  none
+ */
+static void ldm_frag_free (struct list_head *list)
+{
+	struct list_head *item, *tmp;
+
+	BUG_ON (!list);
+
+	list_for_each_safe (item, tmp, list)
+		kfree (list_entry (item, struct frag, list));
+}
+
+/**
+ * ldm_frag_commit - Validate fragmented VBLKs and add them to the database
+ * @frags:  Linked list of VBLK fragments
+ * @ldb:    Cache of the database structures
+ *
+ * Now that all the fragmented VBLKs have been collected, they must be added to
+ * the database for later use.
+ *
+ * Return:  'true'   All the fragments we added successfully
+ *          'false'  One or more of the fragments we invalid
+ */
+static bool ldm_frag_commit (struct list_head *frags, struct ldmdb *ldb)
+{
+	struct frag *f;
+	struct list_head *item;
+
+	BUG_ON (!frags || !ldb);
+
+	list_for_each (item, frags) {
+		f = list_entry (item, struct frag, list);
+
+		if (f->map != 0xFF) {
+			ldm_error ("VBLK group %d is incomplete (0x%02x).",
+				f->group, f->map);
+			return false;
+		}
+
+		if (!ldm_ldmdb_add (f->data, f->num*ldb->vm.vblk_size, ldb))
+			return false;		/* Already logged */
+	}
+	return true;
+}
+
+/**
+ * ldm_get_vblks - Read the on-disk database of VBLKs into memory
+ * @state: Partition check state including device holding the LDM Database
+ * @base:  Offset, into @state->bdev, of the database
+ * @ldb:   Cache of the database structures
+ *
+ * To use the information from the VBLKs, they need to be read from the disk,
+ * unpacked and validated.  We cache them in @ldb according to their type.
+ *
+ * Return:  'true'   All the VBLKs were read successfully
+ *          'false'  An error occurred
+ */
+static bool ldm_get_vblks(struct parsed_partitions *state, unsigned long base,
+			  struct ldmdb *ldb)
+{
+	int size, perbuf, skip, finish, s, v, recs;
+	u8 *data = NULL;
+	Sector sect;
+	bool result = false;
+	LIST_HEAD (frags);
+
+	BUG_ON(!state || !ldb);
+
+	size   = ldb->vm.vblk_size;
+	perbuf = 512 / size;
+	skip   = ldb->vm.vblk_offset >> 9;		/* Bytes to sectors */
+	finish = (size * ldb->vm.last_vblk_seq) >> 9;
+
+	for (s = skip; s < finish; s++) {		/* For each sector */
+		data = read_part_sector(state, base + OFF_VMDB + s, &sect);
+		if (!data) {
+			ldm_crit ("Disk read failed.");
+			goto out;
+		}
+
+		for (v = 0; v < perbuf; v++, data+=size) {  /* For each vblk */
+			if (MAGIC_VBLK != get_unaligned_be32(data)) {
+				ldm_error ("Expected to find a VBLK.");
+				goto out;
+			}
+
+			recs = get_unaligned_be16(data + 0x0E);	/* Number of records */
+			if (recs == 1) {
+				if (!ldm_ldmdb_add (data, size, ldb))
+					goto out;	/* Already logged */
+			} else if (recs > 1) {
+				if (!ldm_frag_add (data, size, &frags))
+					goto out;	/* Already logged */
+			}
+			/* else Record is not in use, ignore it. */
+		}
+		put_dev_sector (sect);
+		data = NULL;
+	}
+
+	result = ldm_frag_commit (&frags, ldb);	/* Failures, already logged */
+out:
+	if (data)
+		put_dev_sector (sect);
+	ldm_frag_free (&frags);
+
+	return result;
+}
+
+/**
+ * ldm_free_vblks - Free a linked list of vblk's
+ * @lh:  Head of a linked list of struct vblk
+ *
+ * Free a list of vblk's and free the memory used to maintain the list.
+ *
+ * Return:  none
+ */
+static void ldm_free_vblks (struct list_head *lh)
+{
+	struct list_head *item, *tmp;
+
+	BUG_ON (!lh);
+
+	list_for_each_safe (item, tmp, lh)
+		kfree (list_entry (item, struct vblk, list));
+}
+
+
+/**
+ * ldm_partition - Find out whether a device is a dynamic disk and handle it
+ * @state: Partition check state including device holding the LDM Database
+ *
+ * This determines whether the device @bdev is a dynamic disk and if so creates
+ * the partitions necessary in the gendisk structure pointed to by @hd.
+ *
+ * We create a dummy device 1, which contains the LDM database, and then create
+ * each partition described by the LDM database in sequence as devices 2+. For
+ * example, if the device is hda, we would have: hda1: LDM database, hda2, hda3,
+ * and so on: the actual data containing partitions.
+ *
+ * Return:  1 Success, @state->bdev is a dynamic disk and we handled it
+ *          0 Success, @state->bdev is not a dynamic disk
+ *         -1 An error occurred before enough information had been read
+ *            Or @state->bdev is a dynamic disk, but it may be corrupted
+ */
+int ldm_partition(struct parsed_partitions *state)
+{
+	struct ldmdb  *ldb;
+	unsigned long base;
+	int result = -1;
+
+	BUG_ON(!state);
+
+	/* Look for signs of a Dynamic Disk */
+	if (!ldm_validate_partition_table(state))
+		return 0;
+
+	ldb = kmalloc (sizeof (*ldb), GFP_KERNEL);
+	if (!ldb) {
+		ldm_crit ("Out of memory.");
+		goto out;
+	}
+
+	/* Parse and check privheads. */
+	if (!ldm_validate_privheads(state, &ldb->ph))
+		goto out;		/* Already logged */
+
+	/* All further references are relative to base (database start). */
+	base = ldb->ph.config_start;
+
+	/* Parse and check tocs and vmdb. */
+	if (!ldm_validate_tocblocks(state, base, ldb) ||
+	    !ldm_validate_vmdb(state, base, ldb))
+	    	goto out;		/* Already logged */
+
+	/* Initialize vblk lists in ldmdb struct */
+	INIT_LIST_HEAD (&ldb->v_dgrp);
+	INIT_LIST_HEAD (&ldb->v_disk);
+	INIT_LIST_HEAD (&ldb->v_volu);
+	INIT_LIST_HEAD (&ldb->v_comp);
+	INIT_LIST_HEAD (&ldb->v_part);
+
+	if (!ldm_get_vblks(state, base, ldb)) {
+		ldm_crit ("Failed to read the VBLKs from the database.");
+		goto cleanup;
+	}
+
+	/* Finally, create the data partition devices. */
+	if (ldm_create_data_partitions(state, ldb)) {
+		ldm_debug ("Parsed LDM database successfully.");
+		result = 1;
+	}
+	/* else Already logged */
+
+cleanup:
+	ldm_free_vblks (&ldb->v_dgrp);
+	ldm_free_vblks (&ldb->v_disk);
+	ldm_free_vblks (&ldb->v_volu);
+	ldm_free_vblks (&ldb->v_comp);
+	ldm_free_vblks (&ldb->v_part);
+out:
+	kfree (ldb);
+	return result;
+}