xfs_bmap(8) - man - phpMan

xfs_bmap(8)                            System Manager's Manual                           xfs_bmap(8)



NAME
       xfs_bmap - print block mapping for an XFS file

SYNOPSIS
       xfs_bmap [ -adelpv ] [ -n num_extents ] file
       xfs_bmap -V

DESCRIPTION
       xfs_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 correspond‐
       ing 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.

OPTIONS
       -a     If this option is specified, information about the file's attribute  fork  is  printed
              instead of the default data fork.

       -e     If  this option is used, xfs_bmap obtains all delayed allocation extents, and does not
              flush dirty pages to disk before querying extent data. With the -v option,  the  flags
              column will show which extents have not yet been allocated.

       -l     If this 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.

              This flag has no effect if the -v option is used.

       -n num_extents
              If this option is given, xfs_bmap will display at most num_extents extents. In the ab‐
              sence of -n, xfs_bmap will display all extents in the file.

       -p     If  this option is used, xfs_bmap obtains all unwritten (preallocated) extents that do
              not contain written data. With the -v option, the flags column will show which extents
              are preallocated/unwritten.

       -v     Shows  verbose information. When this flag is specified, additional AG specific infor‐
              mation is appended to each line in the following form:

                   agno (startagoffset..endagoffset) nblocks flags

              A second -v option will print out the flags legend.

       -V     Prints the version number and exits.

SEE ALSO
       xfs_fsr(8), xfs(5).



                                                                                         xfs_bmap(8)