Thanks for writing a good commit message! > NVMe namespaces may define an atomic boundary, whereby no atomic guarantees > are provided for a write which straddles this per-lba space boundary. The > block layer merging policy is such that no merges may occur in which the > resultant request would straddle such a boundary. > > Unlike SCSI, NVMe specifies no granularity or alignment rules. Well, the boundary really is sort of a granularity and alignment, isn't it?