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>

*** 19,28 ****
--- 19,30 ----
   * 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
  
*** 513,523 ****
--- 515,538 ----
   * 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 */