Illumos 4757, 4913

4757 ZFS embedded-data block pointers ("zero block compression")
4913 zfs release should not be subject to space checks

Reviewed by: Adam Leventhal <ahl@delphix.com>
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/4757
  https://www.illumos.org/issues/4913
  https://github.com/illumos/illumos-gate/commit/5d7b4d4

Porting notes:

For compatibility with the fastpath code the zio_done() function
needed to be updated.  Because embedded-data block pointers do
not require DVAs to be allocated the associated vdevs will not
be marked and therefore should not be unmarked.

Ported by: Tim Chase <tim@chase2k.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2544

include/libzfs.h

@@ -39,6 +39,7 @@
 #include <sys/fs/zfs.h>
 #include <sys/avl.h>
 #include <ucred.h>
+#include <libzfs_core.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -614,13 +615,16 @@ typedef struct sendflags {
 
 	/* show progress (ie. -v) */
 	boolean_t progress;
+
+	/* WRITE_EMBEDDED records of type DATA are permitted */
+	boolean_t embed_data;
 } sendflags_t;
 
 typedef boolean_t (snapfilter_cb_t)(zfs_handle_t *, void *);
 
 extern int zfs_send(zfs_handle_t *, const char *, const char *,
     sendflags_t *, int, snapfilter_cb_t, void *, nvlist_t **);
-extern int zfs_send_one(zfs_handle_t *, const char *, int);
+extern int zfs_send_one(zfs_handle_t *, const char *, int, enum lzc_send_flags);
 
 extern int zfs_promote(zfs_handle_t *);
 extern int zfs_hold(zfs_handle_t *, const char *, const char *,