1xfs_bmap(8)                 System Manager's Manual                xfs_bmap(8)
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NAME

6       xfs_bmap - print block mapping for an XFS file
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SYNOPSIS

9       xfs_bmap [ -adlpv ] [ -n num_extents ] file
10       xfs_bmap -V
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DESCRIPTION

13       xfs_bmap prints the map of disk blocks used by files in an XFS filesys‐
14       tem.  The map lists each extent used by the file, as well as regions in
15       the  file that do not have any corresponding blocks (holes).  Each line
16       of the listings takes the following form:
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18              extent: [startoffset..endoffset]: startblock..endblock
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20       Holes are marked by replacing the startblock..endblock with hole.   All
21       the  file  offsets  and disk blocks are in units of 512-byte blocks, no
22       matter what the filesystem's block size is.
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OPTIONS

25       -a     If this  option  is  specified,  information  about  the  file's
26              attribute fork is printed instead of the default data fork.
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28       -d     If  portions  of  the file have been migrated offline by a DMAPI
29              application, a DMAPI read event will be generated to bring those
30              portions back online before the disk block map is printed.  How‐
31              ever if the -d option is used, no DMAPI read event will be  gen‐
32              erated for a DMAPI file and offline portions will be reported as
33              holes.
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35       -l     If this option is used, then
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37                   <nblocks>  blocks
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39              will be appended to each line.  nblocks is  the  length  of  the
40              extent described on the line in units of 512-byte blocks.
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42              This flag has no effect if the -v option is used.
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44       -n num_extents
45              If this option is given, xfs_bmap obtains the extent list of the
46              file in groups of num_extents extents. In  the  absence  of  -n,
47              xfs_bmap  queries  the  system  for the number of extents in the
48              file and uses that value to compute the group size.
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50       -p     If this option is used, xfs_bmap obtains all unwritten (preallo‐
51              cated)  extents  that  do  not contain written data. With the -v
52              option, the flags column will show which  extents  are  preallo‐
53              cated/unwritten.
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55       -v     Shows  verbose  information.  When this flag is specified, addi‐
56              tional AG specific information is appended to each line  in  the
57              following form:
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59                   agno (startagoffset..endagoffset) nblocks flags
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61              A second -v option will print out the flags legend.
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63       -V     Prints the version number and exits.
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SEE ALSO

66       xfs_fsr(8), xfs(5).
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