block: move ref_tag calculation func to the block layer

Currently this function is implemented in the scsi layer, but it's
actual place should be the block layer since T10-PI is a general
data integrity feature that is used in the nvme protocol as well.

Suggested-by: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/infiniband/ulp/iser/iser_memory.c

@@ -311,7 +311,7 @@ iser_set_dif_domain(struct scsi_cmnd *sc, struct ib_sig_attrs *sig_attrs,
 {
 	domain->sig_type = IB_SIG_TYPE_T10_DIF;
 	domain->sig.dif.pi_interval = scsi_prot_interval(sc);
-	domain->sig.dif.ref_tag = scsi_prot_ref_tag(sc);
+	domain->sig.dif.ref_tag = t10_pi_ref_tag(sc->request);
 	/*
 	 * At the moment we hard code those, but in the future
 	 * we will take them from sc.

drivers/nvme/host/core.c

@@ -611,8 +611,7 @@ static inline blk_status_t nvme_setup_rw(struct nvme_ns *ns,
 		case NVME_NS_DPS_PI_TYPE2:
 			control |= NVME_RW_PRINFO_PRCHK_GUARD |
 					NVME_RW_PRINFO_PRCHK_REF;
-			cmnd->rw.reftag = cpu_to_le32(
-					nvme_block_nr(ns, blk_rq_pos(req)));
+			cmnd->rw.reftag = cpu_to_le32(t10_pi_ref_tag(req));
 			break;
 		}
 	}

drivers/scsi/mpt3sas/mpt3sas_scsih.c

@@ -4568,7 +4568,7 @@ _scsih_setup_eedp(struct MPT3SAS_ADAPTER *ioc, struct scsi_cmnd *scmd,
 		    MPI2_SCSIIO_EEDPFLAGS_CHECK_REFTAG |
 		    MPI2_SCSIIO_EEDPFLAGS_CHECK_GUARD;
 		mpi_request->CDB.EEDP32.PrimaryReferenceTag =
-		    cpu_to_be32(scsi_prot_ref_tag(scmd));
+		    cpu_to_be32(t10_pi_ref_tag(scmd->request));
 		break;
 
 	case SCSI_PROT_DIF_TYPE3:

drivers/scsi/sd_dif.c

@@ -124,7 +124,7 @@ void sd_dif_prepare(struct scsi_cmnd *scmd)
 	if (sdkp->protection_type == T10_PI_TYPE3_PROTECTION)
 		return;
 
-	phys = scsi_prot_ref_tag(scmd);
+	phys = t10_pi_ref_tag(scmd->request);
 
 	__rq_for_each_bio(bio, scmd->request) {
 		struct bio_integrity_payload *bip = bio_integrity(bio);
@@ -176,7 +176,7 @@ void sd_dif_complete(struct scsi_cmnd *scmd, unsigned int good_bytes)
 		return;
 
 	intervals = good_bytes / scsi_prot_interval(scmd);
-	phys = scsi_prot_ref_tag(scmd);
+	phys = t10_pi_ref_tag(scmd->request);
 
 	__rq_for_each_bio(bio, scmd->request) {
 		struct bio_integrity_payload *bip = bio_integrity(bio);

include/linux/t10-pi.h

@@ -37,6 +37,16 @@ struct t10_pi_tuple {
 #define T10_PI_APP_ESCAPE cpu_to_be16(0xffff)
 #define T10_PI_REF_ESCAPE cpu_to_be32(0xffffffff)
 
+static inline u32 t10_pi_ref_tag(struct request *rq)
+{
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+	return blk_rq_pos(rq) >>
+		(rq->q->integrity.interval_exp - 9) & 0xffffffff;
+#else
+	return -1U;
+#endif
+}
+
 extern const struct blk_integrity_profile t10_pi_type1_crc;
 extern const struct blk_integrity_profile t10_pi_type1_ip;
 extern const struct blk_integrity_profile t10_pi_type3_crc;

include/scsi/scsi_cmnd.h

@@ -4,6 +4,7 @@
 
 #include <linux/dma-mapping.h>
 #include <linux/blkdev.h>
+#include <linux/t10-pi.h>
 #include <linux/list.h>
 #include <linux/types.h>
 #include <linux/timer.h>
@@ -313,12 +314,6 @@ static inline unsigned int scsi_prot_interval(struct scsi_cmnd *scmd)
 	return scmd->device->sector_size;
 }
 
-static inline u32 scsi_prot_ref_tag(struct scsi_cmnd *scmd)
-{
-	return blk_rq_pos(scmd->request) >>
-		(ilog2(scsi_prot_interval(scmd)) - 9) & 0xffffffff;
-}
-
 static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)
 {
 	return cmd->prot_sdb ? cmd->prot_sdb->table.nents : 0;