Re: fix read repair on compressed extents

[Christoph Hellwig <hch@lst.de>]

Any chance to get a review on this one?

On Thu, Jun 23, 2022 at 07:53:34AM +0200, Christoph Hellwig wrote:
> Hi all,
> 
> while looking into the repair code I found that read repair of compressed
> extents is current fundamentally broken, in that repair tries to write
> the uncompressed data into a corrupted extent during a repair.  This is
> demonstrated by the "btrfs: test read repair on a corrupted compressed
> extent" test submitted to xfstests.
> 
> This series fixes that, but is a bit invaside as it requires both
> refactoring of the compression code and changes to the repair code to
> not look up the logic address on every repair attempt.  On the plus
> side it removes a whole lot of code.
> 
> It is based on the for-next branch plus my "btrfs: repair all known bad
> mirrors" patch.
> 
> Diffstat:
>  compression.c |  287 ++++++++++++++++------------------------------------------
>  compression.h |   11 --
>  ctree.h       |    4 
>  extent_io.c   |   93 +++++++-----------
>  extent_io.h   |    9 -
>  inode.c       |   34 +++---
>  6 files changed, 148 insertions(+), 290 deletions(-)
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