xfs: Add support for multi rtgroup shrink+removal

Nirjhar Roy (IBM)
2026-02-19T05:58:31Z

Hi all,

This series adds online support for shrinking and removing multiple
realtime groups in XFS.

Currently, realtime group shrink/removal operations are not available.
This series extends the infrastructure to allow online shrinking/removal of
multiple rtgroups in a single operation.

The work is organized into three sub-patchsets:

1. Kernel changes
- Core filesystem changes enabling multi-rtgroup shrink/removal.

2. xfsprogs updates
- Changes to xfs_growfs allow the shrink requests to be passed to the kernel.

3. fstests additions
- Test coverage validating grow, shrink and removal of multiple rtgroups.

Each patch includes details describing the implementation and design considerations.

Comments and reviews are greatly appreciated.