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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO | COLOPHON |
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xfs_bmap(8) System Manager's Manual xfs_bmap(8)
xfs_bmap - print block mapping for an XFS file
xfs_bmap [ -adelpv ] [ -n num_extents ] file
xfs_bmap -V
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 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.
-a If this option is specified, information about the file's
attribute fork is printed instead of the default data
fork.
-d 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.
-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 absence 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 information 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.
xfs_fsr(8), xfs(5).
This page is part of the xfsprogs (utilities for XFS filesystems)
project. Information about the project can be found at
⟨http://xfs.org/⟩. If you have a bug report for this manual page,
send it to linux-xfs@vger.kernel.org. This page was obtained
from the project's upstream Git repository
⟨https://git.kernel.org/pub/scm/fs/xfs/xfsprogs-dev.git⟩ on
2020-12-18. (At that time, the date of the most recent commit
that was found in the repository was 2020-12-11.) If you
discover any rendering problems in this HTML version of the page,
or you believe there is a better or more up-to-date source for
the page, or you have corrections or improvements to the
information in this COLOPHON (which is not part of the original
manual page), send a mail to man-pages@man7.org
xfs_bmap(8)
Pages that refer to this page: xfs_io(8)
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