1518e2e1aSwdenk /* 2518e2e1aSwdenk * (C) Copyright 2003 - 2004 3518e2e1aSwdenk * Sysgo AG, <www.elinos.com>, Pavel Bartusek <pba@sysgo.com> 4518e2e1aSwdenk * 5518e2e1aSwdenk * This program is free software; you can redistribute it and/or modify 6518e2e1aSwdenk * it under the terms of the GNU General Public License as published by 7518e2e1aSwdenk * the Free Software Foundation; either version 2 of the License, or 8518e2e1aSwdenk * (at your option) any later version. 9518e2e1aSwdenk * 10518e2e1aSwdenk * This program is distributed in the hope that it will be useful, 11518e2e1aSwdenk * but WITHOUT ANY WARRANTY; without even the implied warranty of 12518e2e1aSwdenk * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13518e2e1aSwdenk * GNU General Public License for more details. 14518e2e1aSwdenk * 15518e2e1aSwdenk * You should have received a copy of the GNU General Public License 16518e2e1aSwdenk * along with this program; if not, write to the Free Software 17518e2e1aSwdenk * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 18518e2e1aSwdenk */ 19518e2e1aSwdenk 20518e2e1aSwdenk 21518e2e1aSwdenk #include <common.h> 22518e2e1aSwdenk #include <config.h> 23518e2e1aSwdenk #include <reiserfs.h> 24518e2e1aSwdenk 25518e2e1aSwdenk #include "reiserfs_private.h" 26518e2e1aSwdenk 27518e2e1aSwdenk static block_dev_desc_t *reiserfs_block_dev_desc; 28*650f3664SRob Herring static disk_partition_t *part_info; 29518e2e1aSwdenk 30518e2e1aSwdenk 31*650f3664SRob Herring void reiserfs_set_blk_dev(block_dev_desc_t *rbdd, disk_partition_t *info) 32518e2e1aSwdenk { 33518e2e1aSwdenk reiserfs_block_dev_desc = rbdd; 34*650f3664SRob Herring part_info = info; 35518e2e1aSwdenk } 36518e2e1aSwdenk 37518e2e1aSwdenk 38518e2e1aSwdenk int reiserfs_devread (int sector, int byte_offset, int byte_len, char *buf) 39518e2e1aSwdenk { 40518e2e1aSwdenk char sec_buf[SECTOR_SIZE]; 41518e2e1aSwdenk unsigned block_len; 42518e2e1aSwdenk /* 43518e2e1aSwdenk unsigned len = byte_len; 44518e2e1aSwdenk u8 *start = buf; 45518e2e1aSwdenk */ 46518e2e1aSwdenk /* 47518e2e1aSwdenk * Check partition boundaries 48518e2e1aSwdenk */ 49518e2e1aSwdenk if (sector < 0 50518e2e1aSwdenk || ((sector + ((byte_offset + byte_len - 1) >> SECTOR_BITS)) 51*650f3664SRob Herring >= part_info->size)) { 52b79a11ccSwdenk /* errnum = ERR_OUTSIDE_PART; */ 53518e2e1aSwdenk printf (" ** reiserfs_devread() read outside partition\n"); 54518e2e1aSwdenk return 0; 55518e2e1aSwdenk } 56518e2e1aSwdenk 57518e2e1aSwdenk /* 58518e2e1aSwdenk * Get the read to the beginning of a partition. 59518e2e1aSwdenk */ 60518e2e1aSwdenk sector += byte_offset >> SECTOR_BITS; 61518e2e1aSwdenk byte_offset &= SECTOR_SIZE - 1; 62518e2e1aSwdenk 63518e2e1aSwdenk #if defined(DEBUG) 64518e2e1aSwdenk printf (" <%d, %d, %d> ", sector, byte_offset, byte_len); 65518e2e1aSwdenk #endif 66518e2e1aSwdenk 67518e2e1aSwdenk 68518e2e1aSwdenk if (reiserfs_block_dev_desc == NULL) 69518e2e1aSwdenk return 0; 70518e2e1aSwdenk 71518e2e1aSwdenk 72518e2e1aSwdenk if (byte_offset != 0) { 73518e2e1aSwdenk /* read first part which isn't aligned with start of sector */ 74518e2e1aSwdenk if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev, 75*650f3664SRob Herring part_info->start + sector, 1, 76*650f3664SRob Herring (unsigned long *)sec_buf) != 1) { 77518e2e1aSwdenk printf (" ** reiserfs_devread() read error\n"); 78518e2e1aSwdenk return 0; 79518e2e1aSwdenk } 80518e2e1aSwdenk memcpy(buf, sec_buf+byte_offset, min(SECTOR_SIZE-byte_offset, byte_len)); 81518e2e1aSwdenk buf+=min(SECTOR_SIZE-byte_offset, byte_len); 82518e2e1aSwdenk byte_len-=min(SECTOR_SIZE-byte_offset, byte_len); 83518e2e1aSwdenk sector++; 84518e2e1aSwdenk } 85518e2e1aSwdenk 86518e2e1aSwdenk /* read sector aligned part */ 87518e2e1aSwdenk block_len = byte_len & ~(SECTOR_SIZE-1); 88518e2e1aSwdenk if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev, 89*650f3664SRob Herring part_info->start + sector, block_len/SECTOR_SIZE, 90*650f3664SRob Herring (unsigned long *)buf) != block_len/SECTOR_SIZE) { 91518e2e1aSwdenk printf (" ** reiserfs_devread() read error - block\n"); 92518e2e1aSwdenk return 0; 93518e2e1aSwdenk } 94518e2e1aSwdenk buf+=block_len; 95518e2e1aSwdenk byte_len-=block_len; 96518e2e1aSwdenk sector+= block_len/SECTOR_SIZE; 97518e2e1aSwdenk 98518e2e1aSwdenk if ( byte_len != 0 ) { 99518e2e1aSwdenk /* read rest of data which are not in whole sector */ 100518e2e1aSwdenk if (reiserfs_block_dev_desc->block_read(reiserfs_block_dev_desc->dev, 101*650f3664SRob Herring part_info->start + sector, 1, 102*650f3664SRob Herring (unsigned long *)sec_buf) != 1) { 103518e2e1aSwdenk printf (" ** reiserfs_devread() read error - last part\n"); 104518e2e1aSwdenk return 0; 105518e2e1aSwdenk } 106518e2e1aSwdenk memcpy(buf, sec_buf, byte_len); 107518e2e1aSwdenk } 108518e2e1aSwdenk 109518e2e1aSwdenk return 1; 110518e2e1aSwdenk } 111