LVM Partition Formatted as BTRFS Filesystem Resizing

Problem

I want to shrink my LVM partition formatted as BTRFS filesystem by 60GB, and then using the free space to extend swap partition.

Solution

1.Shrink the BTRFS volume:

 # btrfs filesystem resize -60G /

 Resize device id 1 (/dev/mapper/czl-czl--root) from 926.84GiB to 866.84GiB

2.Shrink the LVM volume:

 # lvresize -L-60GB /dev/czl/czl-root

   File system btrfs found on czl/czl-root.
   File system size (866.84 GiB) is equal to the requested size (866.84 GiB).
   File system reduce is not needed, skipping.
   Size of logical volume czl/czl-root changed from 926.84 GiB (237272 extents) to 866.84 GiB (221912 extents).
   Logical volume czl/czl-root successfully resized.