[SCSI] lib: Add support for the T10 (SCSI) Data Integrity Field CRC

The SCSI Block Protocol uses this 16-bit CRC to verify the integrity
of each data sector.  crc_t10dif() is used by sd_dif.c when performing
I/O to or from disks formatted with protection information.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/include/linux/crc-t10dif.h b/include/linux/crc-t10dif.h
new file mode 100644
index 0000000..a9c96d8
--- /dev/null
+++ b/include/linux/crc-t10dif.h
@@ -0,0 +1,8 @@
+#ifndef _LINUX_CRC_T10DIF_H
+#define _LINUX_CRC_T10DIF_H
+
+#include <linux/types.h>
+
+__u16 crc_t10dif(unsigned char const *, size_t);
+
+#endif