btrfs: regression test for nocsum buffered read's repair

This is to test whether buffered read retry-repair code is able to
work in raid1 case as expected.

Please note that without checksum, btrfs doesn't know if the data
used to repair is correct, so repair is more of resync which makes
sure that both of the copy has the same content.

Commit 20a7db8ab3f2 ("btrfs: add dummy callback for
readpage_io_failed and drop checks") introduced the regression.

The upstream fix is commit 9d0d1c8b1c9d ("Btrfs: bring back repair
during read")

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
3 files changed