[dm-devel] [PATCH v7 0/6] block: Introduce REQ_ALLOCATE flag for REQ_OP_WRITE_ZEROES

[Martin K. Petersen]

Christoph,

> That's why I don't like the whole flags game very much.  I'd rather
> have REQ_OP_WRITE_ZEROES as the integrity operation that gurantees
> zeroing, and a REQ_ALLOCATE that doesn't guarantee zeroing, just some
> deterministic state of the blocks.

I just worry about the proliferation of identical merging and splitting
code throughout the block stack as we add additional single-range, no
payload operations (Verify, etc.). I prefer to enforce the semantics in
the LLD and not in the plumbing. But I won't object to a separate
REQ_OP_ALLOCATE if you find the resulting code duplication acceptable.

-- 
Martin K. Petersen	Oracle Linux Engineering