zfs: Port lz4 compression algorithm from FreeBSD

OSv port details:
- Discarded manpage changes.
- lz4 license was added to the licenses directory.
- Addressed some conflicts in zfs/zfs_ioctl.c.
- Add unused attributed to a few functions in zfs/lz4.c which are
actually unused.

 * Illumos zfs issue #3035 [1] LZ4 compression support in ZFS.

LZ4 is a new high-speed BSD-licensed compression algorithm created
by Yann Collet that delivers very high compression and decompression
performance compared to lzjb (>50% faster on compression, >80% faster
on decompression and around 3x faster on compression of incompressible
data), while giving better compression ratio [1].

FreeBSD commit hash: c6d9dc1

Signed-off-by: Raphael S. Carvalho <[email protected]>
Signed-off-by: Pekka Enberg <[email protected]>

Author: raphaelsc

bsd/sys/cddl/compat/opensolaris/sys/byteorder.h

@@ -42,6 +42,11 @@
 #ifndef _OPENSOLARIS_SYS_BYTEORDER_H_
 #define	_OPENSOLARIS_SYS_BYTEORDER_H_
 
+/* for htonl() */
+#ifndef _KERNEL
+#include <netinet/in.h>
+#endif
+
 #include <endian.h>
 
 #define _BIG_ENDIAN __BIG_ENDIAN
@@ -93,4 +98,6 @@
 #define	ntohll(x)	BSWAP_64(x)
 #endif
 
+#define BE_IN32(xa)	htonl(*((uint32_t *)(void *)(xa)))
+
 #endif /* _OPENSOLARIS_SYS_BYTEORDER_H_ */

bsd/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.c

@@ -21,6 +21,7 @@
 
 /*
  * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  */
 
 #ifdef _KERNEL
@@ -155,4 +156,7 @@ zpool_feature_init(void)
 	zfeature_register(SPA_FEATURE_EMPTY_BPOBJ,
 	    "com.delphix:empty_bpobj", "empty_bpobj",
 	    "Snapshots use less space.", B_TRUE, B_FALSE, NULL);
+	zfeature_register(SPA_FEATURE_LZ4_COMPRESS,
+	    "org.illumos:lz4_compress", "lz4_compress",
+	    "LZ4 compression algorithm support.", B_FALSE, B_FALSE, NULL);
 }

bsd/sys/cddl/contrib/opensolaris/common/zfs/zfeature_common.h

@@ -21,6 +21,7 @@
 
 /*
  * Copyright (c) 2012 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  */
 
 #ifndef _ZFEATURE_COMMON_H
@@ -51,6 +52,7 @@ typedef int (zfeature_func_t)(zfeature_info_t *fi, void *arg);
 static enum spa_feature {
 	SPA_FEATURE_ASYNC_DESTROY,
 	SPA_FEATURE_EMPTY_BPOBJ,
+	SPA_FEATURE_LZ4_COMPRESS,
 	SPA_FEATURES
 } spa_feature_t;
 

bsd/sys/cddl/contrib/opensolaris/common/zfs/zfs_prop.c

@@ -21,6 +21,7 @@
 /*
  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
  * Copyright (c) 2011 by Delphix. All rights reserved.
+ * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  */
 
 /* Portions Copyright 2010 Robert Milkowski */
@@ -96,6 +97,7 @@ zfs_prop_init(void)
 		{ "gzip-8",	ZIO_COMPRESS_GZIP_8 },
 		{ "gzip-9",	ZIO_COMPRESS_GZIP_9 },
 		{ "zle",	ZIO_COMPRESS_ZLE },
+		{ "lz4",	ZIO_COMPRESS_LZ4 },
 		{ NULL }
 	};
 
@@ -211,8 +213,8 @@ zfs_prop_init(void)
 	zprop_register_index(ZFS_PROP_COMPRESSION, "compression",
 	    ZIO_COMPRESS_DEFAULT, PROP_INHERIT,
 	    ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME,
-	    "on | off | lzjb | gzip | gzip-[1-9] | zle", "COMPRESS",
-	    compress_table);
+	    "on | off | lzjb | gzip | gzip-[1-9] | zle | lz4",
+	    "COMPRESS", compress_table);
 	zprop_register_index(ZFS_PROP_SNAPDIR, "snapdir", ZFS_SNAPDIR_HIDDEN,
 	    PROP_INHERIT, ZFS_TYPE_FILESYSTEM,
 	    "hidden | visible", "SNAPDIR", snapdir_table);