u-boot/fs/ext2/dev.c
2004-12-16 17:26:24 +00:00

142 lines
3.7 KiB
C

/*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code of fs/reiserfs/dev.c by
*
* (C) Copyright 2003 - 2004
* Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
*
* 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; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <common.h>
#if (CONFIG_COMMANDS & CFG_CMD_EXT2)
#include <config.h>
#include <ext2fs.h>
static block_dev_desc_t *ext2fs_block_dev_desc;
static disk_partition_t part_info;
#undef DEBUG
int ext2fs_set_blk_dev
(
block_dev_desc_t *rbdd,
int part
)
{
ext2fs_block_dev_desc = rbdd;
if (part == 0)
{
/* disk doesn't use partition table */
part_info.start = 0;
part_info.size = rbdd->lba;
part_info.blksz = rbdd->blksz;
}
else
{
if (get_partition_info (ext2fs_block_dev_desc, part, &part_info))
{
return 0;
}
}
return (part_info.size);
}
int ext2fs_devread
(
int sector,
int byte_offset,
int byte_len,
char *buf
)
{
char sec_buf[SECTOR_SIZE];
unsigned block_len;
/*
* Check partition boundaries
*/
if ((sector < 0) || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) >= part_info.size))
{
/* errnum = ERR_OUTSIDE_PART; */
printf (" ** ext2fs_devread() read outside partition sector %d\n", sector);
return(0);
}
/*
* Get the read to the beginning of a partition.
*/
sector += byte_offset >> SECTOR_BITS;
byte_offset &= SECTOR_SIZE - 1;
#if defined(DEBUG)
printf (" <%d, %d, %d>\n", sector, byte_offset, byte_len);
#endif
if (ext2fs_block_dev_desc == NULL)
{
printf("** Invalid Block Device Descriptor (NULL)\n");
return(0);
}
if (byte_offset != 0)
{
/* read first part which isn't aligned with start of sector */
if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev, part_info.start+sector, 1, (unsigned long *)sec_buf) != 1)
{
printf (" ** ext2fs_devread() read error **\n");
return(0);
}
memcpy(buf, sec_buf+byte_offset, min(SECTOR_SIZE-byte_offset, byte_len));
buf+=min(SECTOR_SIZE-byte_offset, byte_len);
byte_len-=min(SECTOR_SIZE-byte_offset, byte_len);
sector++;
}
/* read sector aligned part */
block_len = byte_len & ~(SECTOR_SIZE-1);
if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev,
part_info.start+sector,
block_len/SECTOR_SIZE,
(unsigned long *)buf) != block_len/SECTOR_SIZE)
{
printf (" ** ext2fs_devread() read error - block\n");
return(0);
}
buf+=block_len;
byte_len-=block_len;
sector+= block_len/SECTOR_SIZE;
if (byte_len != 0)
{
/* read rest of data which are not in whole sector */
if (ext2fs_block_dev_desc->block_read(ext2fs_block_dev_desc->dev,
part_info.start+sector,
1,
(unsigned long *)sec_buf) != 1)
{
printf (" ** ext2fs_devread() read error - last part\n");
return(0);
}
memcpy(buf, sec_buf, byte_len);
}
return(1);
}
#endif /* CFG_CMD_EXT2FS */