[SCSI] qla2xxx: T10 DIF - Handle uninitalized sectors.

Driver needs to update protection bytes for uninitialized sectors as they are
not DMA-d.

Signed-off-by: Arun Easi <arun.easi@qlogic.com>
Reviewed-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/qla2xxx/qla_fw.h b/drivers/scsi/qla2xxx/qla_fw.h
index 691783a..aa69486 100644
--- a/drivers/scsi/qla2xxx/qla_fw.h
+++ b/drivers/scsi/qla2xxx/qla_fw.h
@@ -537,6 +537,11 @@
 	/*
 	 * If DIF Error is set in comp_status, these additional fields are
 	 * defined:
+	 *
+	 * !!! NOTE: Firmware sends expected/actual DIF data in big endian
+	 * format; but all of the "data" field gets swab32-d in the beginning
+	 * of qla2x00_status_entry().
+	 *
 	 * &data[10] : uint8_t report_runt_bg[2];	- computed guard
 	 * &data[12] : uint8_t actual_dif[8];		- DIF Data received
 	 * &data[20] : uint8_t expected_dif[8];		- DIF Data computed