super.c
上传用户:jlfgdled
上传日期:2013-04-10
资源大小:33168k
文件大小:3k
- /*
- * super.c
- *
- * Copyright (C) 2001-2002 Will Dyson <will_dyson@pobox.com>
- *
- * Licensed under the GNU GPL. See the file COPYING for details.
- *
- */
- #include <linux/fs.h>
- #include "befs_fs.h"
- #include "endian.h"
- /**
- * load_befs_sb -- Read from disk and properly byteswap all the fields
- * of the befs superblock
- *
- *
- *
- *
- */
- int
- befs_load_sb(struct super_block *sb, befs_super_block * disk_sb)
- {
- befs_sb_info *befs_sb = BEFS_SB(sb);
- /* byte_order is special, no byte-swap */
- befs_sb->byte_order = disk_sb->fs_byte_order;
- befs_sb->magic1 = fs32_to_cpu(sb, disk_sb->magic1);
- befs_sb->magic2 = fs32_to_cpu(sb, disk_sb->magic2);
- befs_sb->magic3 = fs32_to_cpu(sb, disk_sb->magic3);
- befs_sb->block_size = fs32_to_cpu(sb, disk_sb->block_size);
- befs_sb->block_shift = fs32_to_cpu(sb, disk_sb->block_shift);
- befs_sb->num_blocks = fs64_to_cpu(sb, disk_sb->num_blocks);
- befs_sb->used_blocks = fs64_to_cpu(sb, disk_sb->used_blocks);
- befs_sb->inode_size = fs32_to_cpu(sb, disk_sb->inode_size);
- befs_sb->blocks_per_ag = fs32_to_cpu(sb, disk_sb->blocks_per_ag);
- befs_sb->ag_shift = fs32_to_cpu(sb, disk_sb->ag_shift);
- befs_sb->num_ags = fs32_to_cpu(sb, disk_sb->num_ags);
- befs_sb->log_blocks = fsrun_to_cpu(sb, disk_sb->log_blocks);
- befs_sb->log_start = fs64_to_cpu(sb, disk_sb->log_start);
- befs_sb->log_end = fs64_to_cpu(sb, disk_sb->log_end);
- befs_sb->root_dir = fsrun_to_cpu(sb, disk_sb->root_dir);
- befs_sb->indices = fsrun_to_cpu(sb, disk_sb->indices);
- befs_sb->nls = NULL;
- return BEFS_OK;
- }
- int
- befs_check_sb(struct super_block *sb)
- {
- befs_sb_info *befs_sb = BEFS_SB(sb);
- /* Check magic headers of super block */
- if ((befs_sb->magic1 != BEFS_SUPER_MAGIC1)
- || (befs_sb->magic2 != BEFS_SUPER_MAGIC2)
- || (befs_sb->magic3 != BEFS_SUPER_MAGIC3)) {
- befs_error(sb, "invalid magic header");
- return BEFS_ERR;
- }
- /*
- * Check blocksize of BEFS.
- *
- * Blocksize of BEFS is 1024, 2048, 4096 or 8192.
- */
- if ((befs_sb->block_size != 1024)
- && (befs_sb->block_size != 2048)
- && (befs_sb->block_size != 4096)
- && (befs_sb->block_size != 8192)) {
- befs_error(sb, "invalid blocksize: %u", befs_sb->block_size);
- return BEFS_ERR;
- }
- if (befs_sb->block_size > PAGE_SIZE) {
- befs_error(sb, "blocksize(%u) cannot be larger"
- "than system pagesize(%lu)", befs_sb->block_size,
- PAGE_SIZE);
- return BEFS_ERR;
- }
- /*
- * block_shift and block_size encode the same information
- * in different ways as a consistency check.
- */
- if ((1 << befs_sb->block_shift) != befs_sb->block_size) {
- befs_error(sb, "block_shift disagrees with block_size. "
- "Corruption likely.");
- return BEFS_ERR;
- }
- if (befs_sb->log_start != befs_sb->log_end) {
- befs_error(sb, "Filesystem not clean! There are blocks in the "
- "journal. You must boot into BeOS and mount this volume "
- "to make it clean.");
- return BEFS_ERR;
- }
- return BEFS_OK;
- }