701 UNMAP support for COMSTAR
Contributed by: Sumit Gupta <sumit.gupta@nexenta.com>
Reviewed by: Garrett D'Amore <garrett@nexenta.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: George Wilson <gwilson@zfsmail.com>

@@ -19,10 +19,12 @@
  * CDDL HEADER END
  */
 
 /*
  * Copyright (c) 1982, 2010, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  */
 
 #ifndef _SYS_DKIO_H
 #define _SYS_DKIO_H
 

@@ -513,11 +515,24 @@
  * firmware update type - temporary or permanent use
  */
 #define FW_TYPE_TEMP    0x0             /* temporary use */
 #define FW_TYPE_PERM    0x1             /* permanent use */
 
+/*
+ * ioctl to free space (e.g. SCSI UNMAP) off a disk.
+ */
+#define DKIOCFREE       (DKIOC|50)
 
+typedef struct dkioc_free_s {
+        uint32_t df_flags;
+        uint32_t df_reserved;   /* For easy 64-bit alignment below... */
+        diskaddr_t df_start;
+        diskaddr_t df_length;
+} dkioc_free_t;
+
+#define DF_WAIT_SYNC    0x00000001      /* Wait for full write-out of free. */
+
 #ifdef  __cplusplus
 }
 #endif
 
 #endif /* _SYS_DKIO_H */