+#define DKIOCGETFEATURES _IOR('d', 76, uint32_t)
+#define DKIOCGETPHYSICALBLOCKSIZE _IOR('d', 77, uint32_t)
+#define DKIOCGETCOMMANDPOOLSIZE _IOR('d', 78, uint32_t)
+
+typedef struct
+{
+ uint64_t offset;
+ uint64_t length;
+
+ uint8_t reserved0128[16]; /* reserved, clear to zero */
+} dk_discard_t __attribute__ ((deprecated));
+
+#define DKIOCDISCARD _IOW('d', 31, dk_discard_t)
+