+/*
+ * A DIF-capable target device can be formatted with different
+ * protection schemes. Currently 0 through 3 are defined:
+ *
+ * Type 0 is regular (unprotected) I/O
+ *
+ * Type 1 defines the contents of the guard and reference tags
+ *
+ * Type 2 defines the contents of the guard and reference tags and
+ * uses 32-byte commands to seed the latter
+ *
+ * Type 3 defines the contents of the guard tag only
+ */
+
+enum sd_dif_target_protection_types {
+ SD_DIF_TYPE0_PROTECTION = 0x0,
+ SD_DIF_TYPE1_PROTECTION = 0x1,
+ SD_DIF_TYPE2_PROTECTION = 0x2,
+ SD_DIF_TYPE3_PROTECTION = 0x3,
+};
+
+/*
+ * Data Integrity Field tuple.
+ */
+struct sd_dif_tuple {
+ __be16 guard_tag; /* Checksum */
+ __be16 app_tag; /* Opaque storage */
+ __be32 ref_tag; /* Target LBA or indirect LBA */
+};
+
+#if defined(CONFIG_BLK_DEV_INTEGRITY)
+
+extern void sd_dif_op(struct scsi_cmnd *, unsigned int, unsigned int);
+extern void sd_dif_config_host(struct scsi_disk *);
+extern int sd_dif_prepare(struct request *rq, sector_t, unsigned int);
+extern void sd_dif_complete(struct scsi_cmnd *, unsigned int);
+
+#else /* CONFIG_BLK_DEV_INTEGRITY */
+
+#define sd_dif_op(a, b, c) do { } while (0)
+#define sd_dif_config_host(a) do { } while (0)
+#define sd_dif_prepare(a, b, c) (0)
+#define sd_dif_complete(a, b) (0)
+
+#endif /* CONFIG_BLK_DEV_INTEGRITY */
+