The block integrity subsystem can only work with PI placed in the first bytes of the metadata buffer. The series makes block-integrity support the flexible placement of PI. And changes NVMe driver to make use of the new capability. This helps to (i) enable the more common case for NVMe (PI in last bytes is the norm) (ii) reduce nop profile users (tried by Jens recently [1]). /* For NS 4K+16b, 8b PI, last bytes */ Before: # cat /sys/block/nvme0n1/integrity/format nop After: # cat /sys/block/nvme0n1/integrity/format T10-DIF-TYPE1-CRC Changes since v1: - Reworded commit messsage in patch 2 and 3 (hch) - Variable initialization order change (hch) - Collect reviewed-by [1] https://lore.kernel.org/linux-block/20240111160226.1936351-1-axboe@xxxxxxxxx/ Kanchan Joshi (3): block: refactor guard helpers block: support PI at non-zero offset within metadata nvme: allow integrity when PI is not in first bytes block/bio-integrity.c | 1 + block/blk-integrity.c | 1 + block/t10-pi.c | 72 +++++++++++++++++++++++------------ drivers/nvme/host/core.c | 8 +++- drivers/nvme/host/nvme.h | 1 + include/linux/blk-integrity.h | 1 + include/linux/blkdev.h | 1 + 7 files changed, 60 insertions(+), 25 deletions(-) -- 2.25.1
