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/*
*
* 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>
#include <config.h>
#include <zfs_common.h>
static block_dev_desc_t *zfs_block_dev_desc;
static disk_partition_t *part_info;
void zfs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info)
{
zfs_block_dev_desc = rbdd;
part_info = info;
}
/* err */
int zfs_devread(int sector, int byte_offset, int byte_len, char *buf)
{
short sec_buffer[SECTOR_SIZE/sizeof(short)];
char *sec_buf = (char *)sec_buffer;
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(" ** zfs_devread() read outside partition sector %d\n", sector);
return 1;
}
/*
* Get the read to the beginning of a partition.
*/
sector += byte_offset >> SECTOR_BITS;
byte_offset &= SECTOR_SIZE - 1;
debug(" <%d, %d, %d>\n", sector, byte_offset, byte_len);
if (zfs_block_dev_desc == NULL) {
printf("** Invalid Block Device Descriptor (NULL)\n");
return 1;
}
if (byte_offset != 0) {
/* read first part which isn't aligned with start of sector */
if (zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
part_info->start + sector, 1,
(unsigned long *)sec_buf) != 1) {
printf(" ** zfs_devread() read error **\n");
return 1;
}
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++;
}
if (byte_len == 0)
return 0;
/* read sector aligned part */
block_len = byte_len & ~(SECTOR_SIZE - 1);
if (block_len == 0) {
u8 p[SECTOR_SIZE];
block_len = SECTOR_SIZE;
zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
part_info->start + sector,
1, (unsigned long *)p);
memcpy(buf, p, byte_len);
return 0;
}
if (zfs_block_dev_desc->block_read(zfs_block_dev_desc->dev,
part_info->start + sector, block_len / SECTOR_SIZE,
(unsigned long *) buf) != block_len / SECTOR_SIZE) {
printf(" ** zfs_devread() read error - block\n");
return 1;
}
block_len = byte_len & ~(SECTOR_SIZE - 1);
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 (zfs_block_dev_desc->
block_read(zfs_block_dev_desc->dev,
part_info->start + sector, 1,
(unsigned long *) sec_buf) != 1) {
printf(" ** zfs_devread() read error - last part\n");
return 1;
}
memcpy(buf, sec_buf, byte_len);
}
return 0;
}
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