block: centralize PI remapping logic to the block layer

Currently t10_pi_prepare/t10_pi_complete functions are called during the
NVMe and SCSi layers command preparetion/completion, but their actual
place should be the block layer since T10-PI is a general data integrity
feature that is used by block storage protocols. Introduce .prepare_fn
and .complete_fn callbacks within the integrity profile that each type
can implement according to its needs.

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>

Fixed to not call queue integrity functions if BLK_DEV_INTEGRITY
isn't defined in the config.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 3094f2d513b2..6032bb740cf4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1522,10 +1522,14 @@ struct blk_integrity_iter {
 };
 
 typedef blk_status_t (integrity_processing_fn) (struct blk_integrity_iter *);
+typedef void (integrity_prepare_fn) (struct request *);
+typedef void (integrity_complete_fn) (struct request *, unsigned int);
 
 struct blk_integrity_profile {
         integrity_processing_fn         *generate_fn;
         integrity_processing_fn         *verify_fn;
+        integrity_prepare_fn            *prepare_fn;
+        integrity_complete_fn           *complete_fn;
         const char                      *name;
 };