Recalling the first round of new code for 5.10, in which we added:

- New feature: Widen inode timestamps and quota grace expiration
  timestamps to support dates through the year 2486.
- New feature: storing inode btree counts in the AGI to speed up certain
  mount time per-AG block reservation operatoins and add a little more
  metadata redundancy.

For the second round of new code for 5.10:
- Deprecate the V4 filesystem format, some disused mount options, and some
  legacy sysctl knobs now that we can support dates into the 25th century.
  Note that removal of V4 support will not happen until the early 2030s.
- Fix some probles with inode realtime flag propagation.
- Fix some buffer handling issues when growing a rt filesystem.
- Fix a problem where a BMAP_REMAP unmap call would free rt extents even
  though the purpose of BMAP_REMAP is to avoid freeing the blocks.
- Strengthen the dabtree online scrubber to check hash values on child
  dabtree blocks.
- Actually log new intent items created as part of recovering log intent
  items.
- Fix a bug where quotas weren't attached to an inode undergoing bmap
  intent item recovery.
- Fix a buffer overrun problem with specially crafted log buffer
  headers.
- Various cleanups to type usage and slightly inaccurate comments.
- More cleanups to the xattr, log, and quota code.
- Don't run the (slower) shared-rmap operations on attr fork mappings.
- Fix a bug where we failed to check the LSN of finobt blocks during
  replay and could therefore overwrite newer data with older data.
- Clean up the ugly nested transaction mess that log recovery uses to
  stage intent item recovery in the correct order by creating a proper
  data structure to capture recovered chains.
- Use the capture structure to resume intent item chains with the
  same log space and block reservations as when they were captured.
- Fix a UAF bug in bmap intent item recovery where we failed to maintain
  our reference to the incore inode if the bmap operation needed to
  relog itself to continue.
- Rearrange the defer ops mechanism to finish newly created subtasks
  of a parent task before moving on to the next parent task.
- Automatically relog intent items in deferred ops chains if doing so
  would help us avoid pinning the log tail.  This will help fix some
  log scaling problems now and will facilitate atomic file updates later.
- Fix a deadlock in the GETFSMAP implementation by using an internal
  memory buffer to reduce indirect calls and copies to userspace,
  thereby improving its performance by ~20%.
-----BEGIN PGP SIGNATURE-----
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=7JIh
-----END PGP SIGNATURE-----