diff options
Diffstat (limited to 'fs/befs/super.c')
-rw-r--r-- | fs/befs/super.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/fs/befs/super.c b/fs/befs/super.c new file mode 100644 index 000000000..7c50025c9 --- /dev/null +++ b/fs/befs/super.c @@ -0,0 +1,118 @@ +/* + * 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 <asm/page.h> /* for PAGE_SIZE */ + +#include "befs.h" +#include "super.h" + +/* + * befs_load_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) +{ + struct 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->flags = fs32_to_cpu(sb, disk_sb->flags); + + 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) +{ + struct 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; + } + + + /* ag_shift also encodes the same information as blocks_per_ag in a + * different way, non-fatal consistency check + */ + if ((1 << befs_sb->ag_shift) != befs_sb->blocks_per_ag) + befs_error(sb, "ag_shift disagrees with blocks_per_ag."); + + if (befs_sb->log_start != befs_sb->log_end || + befs_sb->flags == BEFS_DIRTY) { + 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; +} |