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/*
* (C) Copyright 2011 - 2012 Samsung Electronics
* EXT4 filesystem implementation in Uboot by
* Uma Shankar <uma.shankar@samsung.com>
* Manjunatha C Achar <a.manjunatha@samsung.com>
*
* Ext4 Extent data structures are taken from original ext4 fs code
* as found in the linux kernel.
*
* Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com
* Written by Alex Tomas <alex@clusterfs.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* 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.
*
*/
#ifndef __EXT4__
#define __EXT4__
#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
#define EXT4_EXT_MAGIC 0xf30a
#define EXT4_FEATURE_RO_COMPAT_GDT_CSUM 0x0010
#define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040
#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080
#define EXT4_INDIRECT_BLOCKS 12
#define EXT4_BG_INODE_UNINIT 0x0001
#define EXT4_BG_BLOCK_UNINIT 0x0002
#define EXT4_BG_INODE_ZEROED 0x0004
/*
* ext4_inode has i_block array (60 bytes total).
* The first 12 bytes store ext4_extent_header;
* the remainder stores an array of ext4_extent.
*/
/*
* This is the extent on-disk structure.
* It's used at the bottom of the tree.
*/
struct ext4_extent {
__le32 ee_block; /* first logical block extent covers */
__le16 ee_len; /* number of blocks covered by extent */
__le16 ee_start_hi; /* high 16 bits of physical block */
__le32 ee_start_lo; /* low 32 bits of physical block */
};
/*
* This is index on-disk structure.
* It's used at all the levels except the bottom.
*/
struct ext4_extent_idx {
__le32 ei_block; /* index covers logical blocks from 'block' */
__le32 ei_leaf_lo; /* pointer to the physical block of the next *
* level. leaf or next index could be there */
__le16 ei_leaf_hi; /* high 16 bits of physical block */
__u16 ei_unused;
};
/* Each block (leaves and indexes), even inode-stored has header. */
struct ext4_extent_header {
__le16 eh_magic; /* probably will support different formats */
__le16 eh_entries; /* number of valid entries */
__le16 eh_max; /* capacity of store in entries */
__le16 eh_depth; /* has tree real underlying blocks? */
__le32 eh_generation; /* generation of the tree */
};
struct ext_filesystem {
/* Inode size of partition */
uint32_t inodesz;
/* Group Descriptor size */
uint16_t gdsize;
/* Block Device Descriptor */
struct cdev *cdev;
struct ext2_data *data;
struct device *dev;
};
struct ext2fs_node;
int ext4fs_open(struct ext2_data *data, const char *filename, struct ext2fs_node **inode);
int ext4fs_read(char *buf, unsigned len);
int ext4fs_mount(struct ext_filesystem *fs);
void ext4fs_umount(struct ext_filesystem *fs);
char *ext4fs_read_symlink(struct ext2fs_node *node);
void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot);
ssize_t ext4fs_devread(struct ext_filesystem *fs, sector_t sector, int byte_offset, size_t byte_len, char *buf);
long int read_allocated_block(struct ext2fs_node *node, int fileblock);
#endif
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