fibmap

const (
	FiemapExtentSize = 56 // sizeof(struct fiemap_extent)
	FiemapSize       = 32 // sizeof(struct fiemap)

	// Defined in <linux/fs.h>:
	SEEK_SET      = 0 // seek relative to beginning of file
	SEEK_CUR      = 1 // seek relative to current file position
	SEEK_END      = 2 // seek relative to end of file
	SEEK_DATA     = 3 // seek to the next data
	SEEK_HOLE     = 4 // seek to the next hole
	SEEK_MAX      = SEEK_HOLE
	FIBMAP        = 1 // bmap access
	FIGETBSZ      = 2 // get the block size used for bmap
	FS_IOC_FIEMAP = 3223348747

	// Defined in <linux/fiemap.h>:
	FIEMAP_MAX_OFFSET            = ^uint64(0)
	FIEMAP_FLAG_SYNC             = 0x0001 // sync file data before map
	FIEMAP_FLAG_XATTR            = 0x0002 // map extended attribute tree
	FIEMAP_FLAG_CACHE            = 0x0004 // request caching of the extents
	FIEMAP_FLAGS_COMPAT          = (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
	FIEMAP_EXTENT_LAST           = 0x0001 // Last extent in file.
	FIEMAP_EXTENT_UNKNOWN        = 0x0002 // Data location unknown.
	FIEMAP_EXTENT_DELALLOC       = 0x0004 // Location still pending. Sets EXTENT_UNKNOWN.
	FIEMAP_EXTENT_ENCODED        = 0x0008 // Data can not be read while fs is unmounted
	FIEMAP_EXTENT_DATA_ENCRYPTED = 0x0080 // Data is encrypted by fs. Sets EXTENT_NO_BYPASS.
	FIEMAP_EXTENT_NOT_ALIGNED    = 0x0100 // Extent offsets may not be block aligned.
	FIEMAP_EXTENT_DATA_INLINE    = 0x0200 // Data mixed with metadata. Sets EXTENT_NOT_ALIGNED.
	FIEMAP_EXTENT_DATA_TAIL      = 0x0400 // Multiple files in block. Sets EXTENT_NOT_ALIGNED.
	FIEMAP_EXTENT_UNWRITTEN      = 0x0800 // Space allocated, but no data (i.e. zero).
	FIEMAP_EXTENT_MERGED         = 0x1000 // File does not natively support extents. Result merged for efficiency.
	FIEMAP_EXTENT_SHARED         = 0x2000 // Space shared with other files.

	// Defined in <linux/falloc.h>:
	FALLOC_FL_KEEP_SIZE    = 0x01 // default is extend size
	FALLOC_FL_PUNCH_HOLE   = 0x02 // de-allocates range
	FALLOC_FL_NO_HIDE_STAE = 0x04 // reserved codepoint
)