diff options
| -rw-r--r-- | fs/xfs/xfs_ondisk.h | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h index d3e04d20d8d4..c8ba98fae30a 100644 --- a/fs/xfs/xfs_ondisk.h +++ b/fs/xfs/xfs_ondisk.h @@ -125,6 +125,27 @@ xfs_check_ondisk_structs(void) XFS_CHECK_STRUCT_SIZE(struct xfs_inode_log_format, 56); XFS_CHECK_STRUCT_SIZE(struct xfs_qoff_logformat, 20); XFS_CHECK_STRUCT_SIZE(struct xfs_trans_header, 16); + + /* + * The v5 superblock format extended several v4 header structures with + * additional data. While new fields are only accessible on v5 + * superblocks, it's important that the v5 structures place original v4 + * fields/headers in the correct location on-disk. For example, we must + * be able to find magic values at the same location in certain blocks + * regardless of superblock version. + * + * The following checks ensure that various v5 data structures place the + * subset of v4 metadata associated with the same type of block at the + * start of the on-disk block. If there is no data structure definition + * for certain types of v4 blocks, traverse down to the first field of + * common metadata (e.g., magic value) and make sure it is at offset + * zero. + */ + XFS_CHECK_OFFSET(struct xfs_dir3_leaf, hdr.info.hdr, 0); + XFS_CHECK_OFFSET(struct xfs_da3_intnode, hdr.info.hdr, 0); + XFS_CHECK_OFFSET(struct xfs_dir3_data_hdr, hdr.magic, 0); + XFS_CHECK_OFFSET(struct xfs_dir3_free, hdr.hdr.magic, 0); + XFS_CHECK_OFFSET(struct xfs_attr3_leafblock, hdr.info.hdr, 0); } #endif /* __XFS_ONDISK_H */ |