[LU-20056] FLR-EC: Update lfsck for RO-EC

• Type: Technical task
• Resolution: Unresolved
• Priority: Medium
• Labels: FLR-EC FLR-EC-RO
• Severity: 3
• Assignee: WC Triage
• Reporter: Marc Vef

Description

lfsck should be updated and take EC mirrors into account so that they are set correctly. For instance, this can include checking for (and more):

• Bidirectional link between data and parity mirror is correctly set.
• Parity and data component extents/stripe sizes match.
• OST uniqueness between paired data/parity components (if applicable).
• Parity stripe count and number of actual parity stripes are consistent with `lcme_dstripe_count` `lcme_cstripe_count`, and data stripes.

Note that lfsck should not check that parities are correct or recompute them, since this should be done via lfs mirror verify and lfs mirror resync, respectively.