target/sbc: Add DIF TYPE1+TYPE3 read/write verify emulation

This patch adds support for DIF read/write verify emulation
for TARGET_DIF_TYPE1_PROT + TARGET_DIF_TYPE3_PROT operation.

This includes sbc_dif_verify_write() + sbc_dif_verify_read()
calls accessable by backend drivers to perform DIF verify
for SGL based data and protection information.

Also included is sbc_dif_copy_prot() logic to copy protection
information to/from backend provided protection SGLs.

Based on scsi_debug.c DIF TYPE1+TYPE3 emulation.

v2 changes:
  - Select CRC_T10DIF for TARGET_CORE in Kconfig (Fengguang)
  - Drop IP checksum logic from sbc_dif_v1_verify (MKP)
  - Fix offset on app_tag = 0xffff in sbc_dif_verify_read()

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/target/Kconfig b/drivers/target/Kconfig
index 18303686eb58..50aad2eeed6e 100644
--- a/drivers/target/Kconfig
+++ b/drivers/target/Kconfig
@@ -3,6 +3,7 @@ menuconfig TARGET_CORE
 	tristate "Generic Target Core Mod (TCM) and ConfigFS Infrastructure"
 	depends on SCSI && BLOCK
 	select CONFIGFS_FS
+	select CRC_T10DIF
 	default n
 	help
 	Say Y or M here to enable the TCM Storage Engine and ConfigFS enabled