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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>
*
* ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
* Ext4 read optimization taken from Open-Moko
* Qi bootloader
*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code from grub2 fs/ext2.c and fs/fshelp.c by
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
*
*
* 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.
*
*/
#include <common.h>
#include <malloc.h>
#include <linux/stat.h>
#include <linux/time.h>
#include <asm/byteorder.h>
#include "ext4_common.h"
void ext4fs_free_node(struct ext2fs_node *node, struct ext2fs_node *currroot)
{
if ((node != &node->data->diropen) && (node != currroot))
free(node);
}
/*
* Taken from openmoko-kernel mailing list: By Andy green
* Optimized read file API : collects and defers contiguous sector
* reads into one potentially more efficient larger sequential read action
*/
int ext4fs_read_file(struct ext2fs_node *node, int pos,
unsigned int len, char *buf)
{
int i;
int blockcnt;
int log2blocksize = LOG2_EXT2_BLOCK_SIZE(node->data);
int blocksize = 1 << (log2blocksize + DISK_SECTOR_BITS);
unsigned int filesize = le32_to_cpu(node->inode.size);
short ret;
struct ext_filesystem *fs = node->data->fs;
/* Adjust len so it we can't read past the end of the file. */
if (len > filesize)
len = filesize;
blockcnt = ((len + pos) + blocksize - 1) / blocksize;
for (i = pos / blocksize; i < blockcnt; i++) {
int blknr;
int blockoff = pos % blocksize;
int blockend = blocksize;
int skipfirst = 0;
blknr = read_allocated_block(node, i);
if (blknr < 0)
return blknr;
blknr = blknr << log2blocksize;
/* Last block. */
if (i == blockcnt - 1) {
blockend = (len + pos) % blocksize;
/* The last portion is exactly blocksize. */
if (!blockend)
blockend = blocksize;
}
/* First block. */
if (i == pos / blocksize) {
skipfirst = blockoff;
blockend -= skipfirst;
}
if (blknr) {
ret = ext4fs_devread(fs, blknr, skipfirst, blockend, buf);
if (ret)
return ret;
} else {
memset(buf, 0, blockend);
}
buf += blocksize - skipfirst;
}
return len;
}
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