block: Block layer data integrity support

Some block devices support verifying the integrity of requests by way
of checksums or other protection information that is submitted along
with the I/O.

This patch implements support for generating and verifying integrity
metadata, as well as correctly merging, splitting and cloning bios and
requests that have this extra information attached.

See Documentation/block/data-integrity.txt for more information.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/block/Kconfig b/block/Kconfig
index 3e97f2bc446f..1ab7c15c8d7a 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -81,6 +81,18 @@ config BLK_DEV_BSG
 
           If unsure, say N.
 
+config BLK_DEV_INTEGRITY
+        bool "Block layer data integrity support"
+        ---help---
+        Some storage devices allow extra information to be
+        stored/retrieved to help protect the data.  The block layer
+        data integrity option provides hooks which can be used by
+        filesystems to ensure better data integrity.
+
+        Say yes here if you have a storage device that provides the
+        T10/SCSI Data Integrity Field or the T13/ATA External Path
+        Protection.  If in doubt, say N.
+
 endif # BLOCK
 
 config BLOCK_COMPAT