Chapter 2. Common XFS Types

All the following XFS types can be found in xfs_types.h. NULL values are always -1 on disk (ie. all bits for the value set to one).

xfs_ino_t: Unsigned 64 bit absolute inode number (Section 3.3.1, “Inode Numbers”).
xfs_off_t: Signed 64 bit file offset.
xfs_daddr_t: Signed 64 bit disk address.
xfs_agnumber_t: Unsigned 32 bit AG (Chapter 3, Allocation Groups) number.
xfs_agblock_t: Unsigned 32 bit AG relative block number.
xfs_extlen_t: Unsigned 32 bit extent (Chapter 5, Data Extents) length in blocks.
xfs_extnum_t: Signed 32 bit number of extents in a file.
xfs_dablk_t: Unsigned 32 bit block number for directories (Chapter 6, Directories) and extended attributes (Chapter 8, Extended Attributes).
xfs_dahash_t: Unsigned 32 bit hash of a directory file name or extended attribute name.
xfs_dfsbno_t: Unsigned 64 bit filesystem block number combining AG (Chapter 3, Allocation Groups) number and block offset into the AG.
xfs_drfsbno_t: Unsigned 64 bit raw filesystem block number.
xfs_drtbno_t: Unsigned 64 bit extent number in the real-time (Section 3.4, “ Real-time Devices”) sub-volume.
xfs_dfiloff_t: Unsigned 64 bit block offset into a file.
xfs_dfilblks_t: Unsigned 64 bit block count for a file.