diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2011-09-16 08:25:05 +0400 |
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committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-01-04 07:54:06 +0400 |
commit | 9be96f3fd10187f185d84cf878cf032465bcced3 (patch) | |
tree | 432a430ed9e0cbe0c18916cd3c3992f09b3feb37 /block/partitions/ldm.c | |
parent | 4752bc309b7604d507c973c7b7678ac2ce10a058 (diff) | |
download | linux-9be96f3fd10187f185d84cf878cf032465bcced3.tar.xz |
move fs/partitions to block/
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'block/partitions/ldm.c')
-rw-r--r-- | block/partitions/ldm.c | 1570 |
1 files changed, 1570 insertions, 0 deletions
diff --git a/block/partitions/ldm.c b/block/partitions/ldm.c new file mode 100644 index 000000000000..bd8ae788f689 --- /dev/null +++ b/block/partitions/ldm.c @@ -0,0 +1,1570 @@ +/** + * ldm - Support for Windows Logical Disk Manager (Dynamic Disks) + * + * Copyright (C) 2001,2002 Richard Russon <ldm@flatcap.org> + * Copyright (c) 2001-2007 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], + §); + 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], §); + 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, §); + 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, §); + 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); + + data += VBLK_SIZE_HEAD; + size -= VBLK_SIZE_HEAD; + + memcpy (f->data+rec*(size-VBLK_SIZE_HEAD)+VBLK_SIZE_HEAD, 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, §); + 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; +} |