1 files changed, 148 insertions, 0 deletions
diff --git a/sys/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c b/sys/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c
new file mode 100644
index 0000000..c563be4
--- /dev/null
+++ b/sys/contrib/opensolaris/uts/common/fs/zfs/zio_compress.c
@@ -0,0 +1,148 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/zfs_context.h>
+#include <sys/compress.h>
+#include <sys/spa.h>
+#include <sys/zio.h>
+#include <sys/zio_compress.h>
+
+/*
+ * Compression vectors.
+ */
+
+zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = {
+	{NULL,			NULL,			0,	"inherit"},
+	{NULL,			NULL,			0,	"on"},
+	{NULL,			NULL,			0,	"uncompressed"},
+	{lzjb_compress,		lzjb_decompress,	0,	"lzjb"},
+	{NULL,			NULL,			0,	"empty"},
+	{gzip_compress,		gzip_decompress,	1,	"gzip-1"},
+	{gzip_compress,		gzip_decompress,	2,	"gzip-2"},
+	{gzip_compress,		gzip_decompress,	3,	"gzip-3"},
+	{gzip_compress,		gzip_decompress,	4,	"gzip-4"},
+	{gzip_compress,		gzip_decompress,	5,	"gzip-5"},
+	{gzip_compress,		gzip_decompress,	6,	"gzip-6"},
+	{gzip_compress,		gzip_decompress,	7,	"gzip-7"},
+	{gzip_compress,		gzip_decompress,	8,	"gzip-8"},
+	{gzip_compress,		gzip_decompress,	9,	"gzip-9"},
+};
+
+uint8_t
+zio_compress_select(uint8_t child, uint8_t parent)
+{
+	ASSERT(child < ZIO_COMPRESS_FUNCTIONS);
+	ASSERT(parent < ZIO_COMPRESS_FUNCTIONS);
+	ASSERT(parent != ZIO_COMPRESS_INHERIT && parent != ZIO_COMPRESS_ON);
+
+	if (child == ZIO_COMPRESS_INHERIT)
+		return (parent);
+
+	if (child == ZIO_COMPRESS_ON)
+		return (ZIO_COMPRESS_ON_VALUE);
+
+	return (child);
+}
+
+int
+zio_compress_data(int cpfunc, void *src, uint64_t srcsize, void **destp,
+    uint64_t *destsizep, uint64_t *destbufsizep)
+{
+	uint64_t *word, *word_end;
+	uint64_t ciosize, gapsize, destbufsize;
+	zio_compress_info_t *ci = &zio_compress_table[cpfunc];
+	char *dest;
+	uint_t allzero;
+
+	ASSERT((uint_t)cpfunc < ZIO_COMPRESS_FUNCTIONS);
+	ASSERT((uint_t)cpfunc == ZIO_COMPRESS_EMPTY || ci->ci_compress != NULL);
+
+	/*
+	 * If the data is all zeroes, we don't even need to allocate
+	 * a block for it.  We indicate this by setting *destsizep = 0.
+	 */
+	allzero = 1;
+	word = src;
+	word_end = (uint64_t *)(uintptr_t)((uintptr_t)word + srcsize);
+	while (word < word_end) {
+		if (*word++ != 0) {
+			allzero = 0;
+			break;
+		}
+	}
+	if (allzero) {
+		*destp = NULL;
+		*destsizep = 0;
+		*destbufsizep = 0;
+		return (1);
+	}
+
+	if (cpfunc == ZIO_COMPRESS_EMPTY)
+		return (0);
+
+	/* Compress at least 12.5% */
+	destbufsize = P2ALIGN(srcsize - (srcsize >> 3), SPA_MINBLOCKSIZE);
+	if (destbufsize == 0)
+		return (0);
+	dest = zio_buf_alloc(destbufsize);
+
+	ciosize = ci->ci_compress(src, dest, (size_t)srcsize,
+	    (size_t)destbufsize, ci->ci_level);
+	if (ciosize > destbufsize) {
+		zio_buf_free(dest, destbufsize);
+		return (0);
+	}
+
+	/* Cool.  We compressed at least as much as we were hoping to. */
+
+	/* For security, make sure we don't write random heap crap to disk */
+	gapsize = P2ROUNDUP(ciosize, SPA_MINBLOCKSIZE) - ciosize;
+	if (gapsize != 0) {
+		bzero(dest + ciosize, gapsize);
+		ciosize += gapsize;
+	}
+
+	ASSERT3U(ciosize, <=, destbufsize);
+	ASSERT(P2PHASE(ciosize, SPA_MINBLOCKSIZE) == 0);
+	*destp = dest;
+	*destsizep = ciosize;
+	*destbufsizep = destbufsize;
+
+	return (1);
+}
+
+int
+zio_decompress_data(int cpfunc, void *src, uint64_t srcsize,
+	void *dest, uint64_t destsize)
+{
+	zio_compress_info_t *ci = &zio_compress_table[cpfunc];
+
+	ASSERT((uint_t)cpfunc < ZIO_COMPRESS_FUNCTIONS);
+
+	return (ci->ci_decompress(src, dest, srcsize, destsize, ci->ci_level));
+}