[RFC PATCH] nvme-pci: Bounce buffer for interleaved metadata

[Martin K. Petersen]

Sagi,

> It makes sense for FC (and few RDMA devices) that already get
> interleaved metadata from the wire to keep it as is instead of
> scattering it if the backend nvme device supports interleaved mode...

Yeah, assuming that the PI doesn't have to get translated.

> I would say that this support for this is something that belongs in
> the block layer. IIRC mkp also expressed interest in using
> preadv2/pwritev2 to for user-space to use DIF with some accounting on
> the iovec

Indeed.

> so maybe we can add a flag for interleaved metadata.

What would the use case be for this? Userspace target driver? I know
lots of widgets that rely on interleaved but they are all using SPDK.

-- 
Martin K. Petersen	Oracle Linux Engineering