xfs\_bmap(8) System Manager's Manual xfs\_bmap(8)

# [NAME](#NAME)

xfs\_bmap - print block mapping for an XFS file

# [SYNOPSIS](#SYNOPSIS)

**xfs\_bmap** \[ **-adelpv** ] \[ **-n** *num\_extents* ] *file*  
**xfs\_bmap -V**

# [DESCRIPTION](#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 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.

# [OPTIONS](#OPTIONS)

[**-a**](#a)

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

[**-d**](#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**](#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**](#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**](#n)

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**](#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**](#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**](#V)

Prints the version number and exits.

# [SEE ALSO](#SEE_ALSO)

[**xfs\_fsr**(8)](/man/enterprise-packages/xfsprogs-5.10/xfs_fsr.8), [**xfs**(5)](/man/enterprise-packages/xfsprogs-5.10/xfs.5).

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Document: xfs_bmap(8) from xfsprogs-5.10 5.10.0-r48 (Chainguard OS)
Source: https://kernel.googlesource.com/pub/scm/fs/xfs/xfsprogs-dev