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btrfs-map-logical(8) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | SEE ALSO | COLOPHON 

BTRFS-MAP-LOGICAL(8)           Btrfs Manual          BTRFS-MAP-LOGICAL(8)

NAME         top

       btrfs-map-logical - map btrfs logical extent to physical extent

SYNOPSIS         top

       btrfs-map-logical <options> <device>

DESCRIPTION         top

       btrfs-map-logical can be used to find out what the physical
       offsets are on the mirrors, the result is dumped to stdout by
       default.

       Mainly used for debug purpose.

OPTIONS         top

       -l|--logical <logical_num>
           Logical extent to map.

       -c|--copy <copy>
           Copy of the extent to read(usually 1 or 2).

       -o|--output <filename>
           Output file to hold the extent.

       -b|--bytes <bytes>
           Number of bytes to read.

EXIT STATUS         top

       btrfs-map-logical will return 0 if no error happened. If any
       problems happened, 1 will be returned.

SEE ALSO         top

       mkfs.btrfs(8)

COLOPHON         top

       This page is part of the btrfs-progs (btrfs filesystem tools)
       project.  Information about the project can be found at 
       ⟨https://btrfs.wiki.kernel.org/index.php/Btrfs_source_repositories⟩.
       If you have a bug report for this manual page, see
       ⟨https://btrfs.wiki.kernel.org/index.php/Problem_FAQ#How_do_I_report_bugs_and_issues.3F⟩.
       This page was obtained from the project's upstream Git repository
       ⟨git://git.kernel.org/pub/scm/linux/kernel/git/kdave/btrfs-progs.git⟩
       on 2025-08-11.  (At that time, the date of the most recent commit
       that was found in the repository was 2025-06-23.)  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

Btrfs v5.16.1                   02/06/2022           BTRFS-MAP-LOGICAL(8)

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