linux/fs/hfsplus/part_tbl.c

/*
 * linux/fs/hfsplus/part_tbl.c
 *
 * Copyright (C) 1996-1997  Paul H. Hargrove
 * This file may be distributed under the terms of
 * the GNU General Public License.
 *
 * Original code to handle the new style Mac partition table based on
 * a patch contributed by Holger Schemel ([email protected]).
 *
 * In function preconditions the term "valid" applied to a pointer to
 * a structure means that the pointer is non-NULL and the structure it
 * points to has all fields initialized to consistent values.
 *
 */

#include <linux/slab.h>
#include "hfsplus_fs.h"

/* offsets to various blocks */
#define HFS_DD_BLK …
#define HFS_PMAP_BLK …
#define HFS_MDB_BLK …

/* magic numbers for various disk blocks */
#define HFS_DRVR_DESC_MAGIC …
#define HFS_OLD_PMAP_MAGIC …
#define HFS_NEW_PMAP_MAGIC …
#define HFS_SUPER_MAGIC …
#define HFS_MFS_SUPER_MAGIC …

/*
 * The new style Mac partition map
 *
 * For each partition on the media there is a physical block (512-byte
 * block) containing one of these structures.  These blocks are
 * contiguous starting at block 1.
 */
struct new_pmap { … } __packed;

/*
 * The old style Mac partition map
 *
 * The partition map consists for a 2-byte signature followed by an
 * array of these structures.  The map is terminated with an all-zero
 * one of these.
 */
struct old_pmap { … } __packed;

static int hfs_parse_old_pmap(struct super_block *sb, struct old_pmap *pm,
		sector_t *part_start, sector_t *part_size)
{ … }

static int hfs_parse_new_pmap(struct super_block *sb, void *buf,
		struct new_pmap *pm, sector_t *part_start, sector_t *part_size)
{ … }

/*
 * Parse the partition map looking for the start and length of a
 * HFS/HFS+ partition.
 */
int hfs_part_find(struct super_block *sb,
		sector_t *part_start, sector_t *part_size)
{ … }