CA-397084: SR scan tries to deactivate LV in use by tapdisk #712
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Back when this code was written we didn't have leaf coalesce doing snapshot coalesace operations, and so for performance reasons the scan code didn't reference count LVs that it activated on the assuption that nothing else would be in a position to start using the LV in the meantime. This assumption is no longer valid and induces scan failures when a new VDI is detected and the scan tries to deactivate it whilst it is open and in use by tapdisk. Move the scan code to use the lvactivator so that reference counts will be taken and honoured. Additionally, it's possible that more than one VDI might appear so don't treat this as a singular event and track all VDIs that might have been activated and dereference them at the end. Signed-off-by: Mark Syms <[email protected]>
KevinLCtx
approved these changes
Oct 14, 2024
rdn32
approved these changes
Oct 15, 2024
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Back when this code was written we didn't have leaf coalesce doing snapshot coalesace operations, and so for performance reasons the scan code didn't reference count LVs that it activated on the assuption that nothing else would be in a position to start using the LV in the meantime. This assumption is no longer valid and induces scan failures when a new VDI is detected and the scan tries to deactivate it whilst it is open and in use by tapdisk. Move the scan code to use the lvactivator so that reference counts will be taken and honoured. Additionally, it's possible that more than one VDI might appear so don't treat this as a singular event and track all VDIs that might have been activated and dereference them at the end.