BTRFS-MAP-LOGICAL(8) System Manager's Manual BTRFS-MAP-LOGICAL(8)NAME
btrfs-map-logical - map btrfs logical extent to physical extent
SYNOPSIS
btrfs-map-logical [options] <device>
DESCRIPTION
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.
Options
-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 CODE
btrfs-map-logical will return 0 if no error happened. If any problems happened, 1 will be returned.
AUTHOR
Written by Shilong Wang and Wenruo Qu.
COPYRIGHT
Copyright (C) 2013 Fujitsu, Inc. License GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO mkfs.btrfs(8)BTRFS-MAP-LOGICAL(8)
Check Out this Related Man Page
BTRFSCTL(8) System Manager's Manual BTRFSCTL(8)NAME
btrfsctl - control a btrfs filesystem
SYNOPSIS
btrfsctl [ -d file|directory ] [ -s snapshot-name directory ] [ -S subvolume-name directory ] [ -r [+-]size ] [ -A device ] [ -a ] [
-c ]
DESCRIPTION
btrfsctl is used to control the filesystem and the files and directories stored. It is the tool to create a new snapshot for the filesys-
tem.
OPTIONS -d file|directory
Defragment a file or a directory. If the argument is a directory, the entire b-tree under the directory is defragged.
-s snapshot-name directory
Creates a new snapshot of the directory specified.
-S subvolume-name directory
Creates a new subvolume.
-r [+|-]size
Resizes the filesystem with the size specified. If the value is preceded with a signed symbol, the filesystem is resized with
respect to the current filesystem size. size can be suffixed by k,m or g to represent kilobytes, megabytes, or gigabytes respec-
tively.
-A device
Scans the device for btrfs filesystem.
-a Scans all devices present in the system for btrfs filesystem.
-c Forces a filesystem sync.
AVAILABILITY
btrfsctl is part of btrfs-progs. Btrfs is currently under heavy development, and not suitable for any uses other than benchmarking and
review. Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for further details.
SEE ALSO mkfs.btrfs(8)BTRFSCTL(8)
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