LXR uboot/fs/reiserfs/dev.c

   1/*
   2 *  (C) Copyright 2003 - 2004
   3 *  Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com>
   4 *
   5 *  This program is free software; you can redistribute it and/or modify
   6 *  it under the terms of the GNU General Public License as published by
   7 *  the Free Software Foundation; either version 2 of the License, or
   8 *  (at your option) any later version.
   9 *
  10 *  This program is distributed in the hope that it will be useful,
  11 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 *  GNU General Public License for more details.
  14 *
  15 *  You should have received a copy of the GNU General Public License
  16 *  along with this program; if not, write to the Free Software
  17 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18 */
  19
  20
  21#include <common.h>
  22#include <config.h>
  23#include <reiserfs.h>
  24
  25#include "reiserfs_private.h"
  26
  27static block_dev_desc_t *reiserfs_block_dev_desc;
  28static disk_partition_t part_info;
  29
  30
  31int reiserfs_set_blk_dev(block_dev_desc_t *rbdd, int part)
  32{
  33        reiserfs_block_dev_desc = rbdd;
  34
  35        if (part == 0) {
  36                /* disk doesn't use partition table */
  37                part_info.start = 0;
  38                part_info.size = rbdd->lba;
  39                part_info.blksz = rbdd->blksz;
  40        } else {
  41                if (get_partition_info (reiserfs_block_dev_desc, part, &part_info)) {
  42                        return 0;
  43                }
  44        }
  45        return (part_info.size);
  46}
  47
  48
  49int reiserfs_devread (int sector, int byte_offset, int byte_len, char *buf)
  50{
  51        char sec_buf[SECTOR_SIZE];
  52        unsigned block_len;
  53/*
  54        unsigned len = byte_len;
  55        u8 *start = buf;
  56*/
  57        /*
  58        *  Check partition boundaries
  59        */
  60        if (sector < 0
  61            || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS))
  62            >= part_info.size)) {
  63/*              errnum = ERR_OUTSIDE_PART; */
  64                printf (" ** reiserfs_devread() read outside partition\n");
  65                return 0;
  66        }
  67
  68        /*
  69         *  Get the read to the beginning of a partition.
  70         */
  71        sector += byte_offset >> SECTOR_BITS;
  72        byte_offset &= SECTOR_SIZE - 1;
  73
  74#if defined(DEBUG)
  75        printf (" <%d, %d, %d> ", sector, byte_offset, byte_len);
  76#endif
  77
  78
  79        if (reiserfs_block_dev_desc == NULL)
  80                return 0;
  81
  82
  83        if (byte_offset != 0) {
  84                /* read first part which isn't aligned with start of sector */
  85                if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev,
  86                    part_info.start+sector, 1, (unsigned long *)sec_buf) != 1) {
  87                        printf (" ** reiserfs_devread() read error\n");
  88                        return 0;
  89                }
  90                memcpy(buf, sec_buf+byte_offset, min(SECTOR_SIZE-byte_offset, byte_len));
  91                buf+=min(SECTOR_SIZE-byte_offset, byte_len);
  92                byte_len-=min(SECTOR_SIZE-byte_offset, byte_len);
  93                sector++;
  94        }
  95
  96        /* read sector aligned part */
  97        block_len = byte_len & ~(SECTOR_SIZE-1);
  98        if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev,
  99            part_info.start+sector, block_len/SECTOR_SIZE, (unsigned long *)buf) !=
 100            block_len/SECTOR_SIZE) {
 101                printf (" ** reiserfs_devread() read error - block\n");
 102                return 0;
 103        }
 104        buf+=block_len;
 105        byte_len-=block_len;
 106        sector+= block_len/SECTOR_SIZE;
 107
 108        if ( byte_len != 0 ) {
 109                /* read rest of data which are not in whole sector */
 110                if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev,
 111                    part_info.start+sector, 1, (unsigned long *)sec_buf) != 1) {
 112                        printf (" ** reiserfs_devread() read error - last part\n");
 113                        return 0;
 114                }
 115                memcpy(buf, sec_buf, byte_len);
 116        }
 117
 118        return 1;
 119}
 120