[MEGAPATCHSET v28] xfs: online repair, second part of part 1

["Darrick J. Wong" <djwong@kernel.org>]

Hi everyone,

[this time not as a reply to v27]

[[this time really not as a reply to v27]]

[[[***** email, this way is insane]]]

I've rebased the online fsck development branches atop 6.7, applied the
changes requested during the review of v27, and reworked the automatic
space reaping code to avoid open-coding EFI log item handling, and
cleaned up a few other things.

In other words, I'm formally submitting part 1 for inclusion in 6.8.

Just like the last several submissions, I would like people to focus the
following:

- Are the major subsystems sufficiently documented that you could figure
  out what the code does?

- Do you see any problems that are severe enough to cause long term
  support hassles? (e.g. bad API design, writing weird metadata to disk)

- Can you spot mis-interactions between the subsystems?

- What were my blind spots in devising this feature?

- Are there missing pieces that you'd like to help build?

- Can I just merge all of this?

The one thing that is /not/ in scope for this review are requests for
more refactoring of existing subsystems.  I'm still running QA round the
clock.  To spare vger, I'm only sending a few patchsets this time.  I
will of course stress test the new mailing infrastructure on 31 Dec with
a full posting, like I always do.

--D