super.c

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/*
 * super.c
 *
 * Copyright (C) 2001-2002 Will Dyson <[email protected]>
 *
 * Licensed under the GNU GPL. See the file COPYING for details.
 *
 */

#include <linux/fs.h>
#include <asm/page.h> /* for PAGE_SIZE */

#include "befs.h"
#include "super.h"

int
befs_load_sb(struct super_block *sb, befs_super_block * disk_sb)
{
    befs_sb_info *befs_sb = BEFS_SB(sb);

    /* Check the byte order of the filesystem */
    if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_LE)
        befs_sb->byte_order = BEFS_BYTESEX_LE;
    else if (disk_sb->fs_byte_order == BEFS_BYTEORDER_NATIVE_BE)
        befs_sb->byte_order = BEFS_BYTESEX_BE;

    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;
}