btrfs-map-logical man page

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


btrfs-map-logical <options> <device>


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

Mainly used for debug purpose.


-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

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

See Also