xfs_bmap(1M)xfs_bmap(1M)NAMExfs_bmap - print block mapping for an XFS file
SYNOPSISxfs_bmap [ -a ] [ -l ] [ -d ] [ -n nnn ] [ -v ] file ...
DESCRIPTIONxfs_bmap prints the map of disk blocks used by files in an XFS
filesystem. The map lists each extent used by the file, as well as
regions in the file that do not have any corresponding blocks (holes).
Each line of the listings takes the following form:
extent: [startoffset..endoffset]: startblock..endblock
Holes are marked by replacing the startblock..endblock with hole. All
the file offsets and disk blocks are in units of 512-byte blocks, no
matter what the filesystem's block size is.
If portions of the file have been migrated offline by a DMAPI
application, a DMAPI read event will be generated to bring those portions
back online before the disk block map is printed. However if the -d
option is used, no DMAPI read event will be generated for a DMAPI file
and offline portions will be reported as holes.
If the -l option is used, then
<nblocks> blocks
will be appended to each line. Nblocks is the length of the extent
described on the line in units of 512-byte blocks.
If the -a option is given, information about the file's attribute fork is
printed instead of the default data fork.
If the -n nnn option is given, xfs_bmap obtains the extent list of the
file in groups of nnn extents. In the absence of -n, xfs_bmap queries
the system for the number of extents in the file and uses that value to
compute the group size.
If the -v option is given, the XFS allocation group and allocation group
offsets are displayed for each extent. If the allocation is on a striped
device, a flag is also displayed indicating if the extent does not fall
on a stripe boundry.
DIAGNOSTICSfcntl(F_GETBMAPX) filename: Invalid argument
The file filename is not in an XFS filesystem.
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xfs_bmap(1M)xfs_bmap(1M)SEE ALSOfcntl(2), lv(7M), xlv(7M).
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