[LU-19995] FLR-EC-IWM: block LCME_FL_IMMEDIATE in --comp-set

• Type: Technical task
• Resolution: Unresolved
• Priority: Medium
• Labels: FLR-EC FLR-EC-IWM
• Severity: 3
• Assignee: WC Triage
• Reporter: Patrick Farrell

Description

The LCME_FL_IMMEDIATE flag is in LCME_USER_COMP_FLAGS, which means lfs setstripe --comp-set --comp-flags immediate is accepted today. This makes no sense – immediate mirroring requires at least 2 mirrors and the AW lock infrastructure. The flag cannot be safely added to an existing component by flipping it via --comp-set.

Adding the immediate flag to a live file requires a layout intent with flush semantics (see LU-19701).

Block LCME_FL_IMMEDIATE in the --comp-set path:

• llapi_layout_file_comp_set() in liblustreapi_layout.c: reject LCME_FL_IMMEDIATE in the flags
• Kernel side (LOD): reject comp-set operations that attempt to add LCME_FL_IMMEDIATE

Add a test verifying the rejection.

Issue Links

• is blocked by: LU-19993 FLR-EC-IWM: lfs setstripe --immediate support