block, libnvdimm, nvme: provide a built-in blk_integrity nop profile

The libnvidmm-btt and nvme drivers use blk_integrity to reserve space
for per-sector metadata, but sometimes without protection checksums.
This property is generically useful, so teach the block core to
internally specify a nop profile if one is not provided at registration

Cc: Keith Busch <>
Cc: Matthew Wilcox <>
Suggested-by: Christoph Hellwig <>
[hch: kill the local nvme nop profile as well]
Acked-by: Martin K. Petersen <>
Signed-off-by: Dan Williams <>
Signed-off-by: Jens Axboe <>
3 files changed