4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
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23 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
27 #pragma ident "@(#)zio_compress.c 1.4 07/03/22 SMI"
29 #include <sys/zfs_context.h>
30 #include <sys/compress.h>
33 #include <sys/zio_compress.h>
36 * Compression vectors.
39 zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = {
40 {NULL, NULL, 0, "inherit"},
41 {NULL, NULL, 0, "on"},
42 {NULL, NULL, 0, "uncompressed"},
43 {lzjb_compress, lzjb_decompress, 0, "lzjb"},
44 {NULL, NULL, 0, "empty"},
45 {gzip_compress, gzip_decompress, 1, "gzip-1"},
46 {gzip_compress, gzip_decompress, 2, "gzip-2"},
47 {gzip_compress, gzip_decompress, 3, "gzip-3"},
48 {gzip_compress, gzip_decompress, 4, "gzip-4"},
49 {gzip_compress, gzip_decompress, 5, "gzip-5"},
50 {gzip_compress, gzip_decompress, 6, "gzip-6"},
51 {gzip_compress, gzip_decompress, 7, "gzip-7"},
52 {gzip_compress, gzip_decompress, 8, "gzip-8"},
53 {gzip_compress, gzip_decompress, 9, "gzip-9"},
57 zio_compress_select(uint8_t child, uint8_t parent)
59 ASSERT(child < ZIO_COMPRESS_FUNCTIONS);
60 ASSERT(parent < ZIO_COMPRESS_FUNCTIONS);
61 ASSERT(parent != ZIO_COMPRESS_INHERIT && parent != ZIO_COMPRESS_ON);
63 if (child == ZIO_COMPRESS_INHERIT)
66 if (child == ZIO_COMPRESS_ON)
67 return (ZIO_COMPRESS_ON_VALUE);
73 zio_compress_data(int cpfunc, void *src, uint64_t srcsize, void **destp,
74 uint64_t *destsizep, uint64_t *destbufsizep)
76 uint64_t *word, *word_end;
77 uint64_t ciosize, gapsize, destbufsize;
78 zio_compress_info_t *ci = &zio_compress_table[cpfunc];
82 ASSERT((uint_t)cpfunc < ZIO_COMPRESS_FUNCTIONS);
83 ASSERT((uint_t)cpfunc == ZIO_COMPRESS_EMPTY || ci->ci_compress != NULL);
86 * If the data is all zeroes, we don't even need to allocate
87 * a block for it. We indicate this by setting *destsizep = 0.
91 word_end = (uint64_t *)(uintptr_t)((uintptr_t)word + srcsize);
92 while (word < word_end) {
105 if (cpfunc == ZIO_COMPRESS_EMPTY)
108 /* Compress at least 12.5% */
109 destbufsize = P2ALIGN(srcsize - (srcsize >> 3), SPA_MINBLOCKSIZE);
110 if (destbufsize == 0)
112 dest = zio_buf_alloc(destbufsize);
114 ciosize = ci->ci_compress(src, dest, (size_t)srcsize,
115 (size_t)destbufsize, ci->ci_level);
116 if (ciosize > destbufsize) {
117 zio_buf_free(dest, destbufsize);
121 /* Cool. We compressed at least as much as we were hoping to. */
123 /* For security, make sure we don't write random heap crap to disk */
124 gapsize = P2ROUNDUP(ciosize, SPA_MINBLOCKSIZE) - ciosize;
126 bzero(dest + ciosize, gapsize);
130 ASSERT3U(ciosize, <=, destbufsize);
131 ASSERT(P2PHASE(ciosize, SPA_MINBLOCKSIZE) == 0);
133 *destsizep = ciosize;
134 *destbufsizep = destbufsize;
140 zio_decompress_data(int cpfunc, void *src, uint64_t srcsize,
141 void *dest, uint64_t destsize)
143 zio_compress_info_t *ci = &zio_compress_table[cpfunc];
145 ASSERT((uint_t)cpfunc < ZIO_COMPRESS_FUNCTIONS);
147 return (ci->ci_decompress(src, dest, srcsize, destsize, ci->ci_level));