module/zfs/zio_compress.c

   1 /*
   2  * CDDL HEADER START
   3  *
   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.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or https://opensource.org/licenses/CDDL-1.0.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  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
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21
  22 /*
  23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  * Copyright (c) 2013 by Saso Kiselkov. All rights reserved.
  26  * Copyright (c) 2013, 2018 by Delphix. All rights reserved.
  27  * Copyright (c) 2019, 2024, Klara, Inc.
  28  * Copyright (c) 2019, Allan Jude
  29  * Copyright (c) 2021, 2024 by George Melikov. All rights reserved.
  30  */
  31
  32 #include <sys/zfs_context.h>
  33 #include <sys/spa.h>
  34 #include <sys/zfeature.h>
  35 #include <sys/zio.h>
  36 #include <sys/zio_compress.h>
  37 #include <sys/zstd/zstd.h>
  38
  39 /*
  40  * If nonzero, every 1/X decompression attempts will fail, simulating
  41  * an undetected memory error.
  42  */
  43 static unsigned long zio_decompress_fail_fraction = 0;
  44
  45 /*
  46  * Compression vectors.
  47  */
  48 zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = {
  49         {"inherit",     0,      NULL,   NULL, NULL},
  50         {"on",          0,      NULL,   NULL, NULL},
  51         {"uncompressed", 0,     NULL,   NULL, NULL},
  52         {"lzjb",        0,
  53             zfs_lzjb_compress,  zfs_lzjb_decompress, NULL},
  54         {"empty",       0,      NULL,   NULL, NULL},
  55         {"gzip-1",      1,
  56             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  57         {"gzip-2",      2,
  58             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  59         {"gzip-3",      3,
  60             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  61         {"gzip-4",      4,
  62             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  63         {"gzip-5",      5,
  64             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  65         {"gzip-6",      6,
  66             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  67         {"gzip-7",      7,
  68             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  69         {"gzip-8",      8,
  70             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  71         {"gzip-9",      9,
  72             zfs_gzip_compress,  zfs_gzip_decompress, NULL},
  73         {"zle",         64,
  74             zfs_zle_compress,   zfs_zle_decompress, NULL},
  75         {"lz4",         0,
  76             zfs_lz4_compress,   zfs_lz4_decompress, NULL},
  77         {"zstd",        ZIO_ZSTD_LEVEL_DEFAULT,
  78             zfs_zstd_compress,  zfs_zstd_decompress, zfs_zstd_decompress_level},
  79 };
  80
  81 uint8_t
  82 zio_complevel_select(spa_t *spa, enum zio_compress compress, uint8_t child,
  83     uint8_t parent)
  84 {
  85         (void) spa;
  86         uint8_t result;
  87
  88         if (!ZIO_COMPRESS_HASLEVEL(compress))
  89                 return (0);
  90
  91         result = child;
  92         if (result == ZIO_COMPLEVEL_INHERIT)
  93                 result = parent;
  94
  95         return (result);
  96 }
  97
  98 enum zio_compress
  99 zio_compress_select(spa_t *spa, enum zio_compress child,
 100     enum zio_compress parent)
 101 {
 102         enum zio_compress result;
 103
 104         ASSERT(child < ZIO_COMPRESS_FUNCTIONS);
 105         ASSERT(parent < ZIO_COMPRESS_FUNCTIONS);
 106         ASSERT(parent != ZIO_COMPRESS_INHERIT);
 107
 108         result = child;
 109         if (result == ZIO_COMPRESS_INHERIT)
 110                 result = parent;
 111
 112         if (result == ZIO_COMPRESS_ON) {
 113                 if (spa_feature_is_active(spa, SPA_FEATURE_LZ4_COMPRESS))
 114                         result = ZIO_COMPRESS_LZ4_ON_VALUE;
 115                 else
 116                         result = ZIO_COMPRESS_LEGACY_ON_VALUE;
 117         }
 118
 119         return (result);
 120 }
 121
 122 size_t
 123 zio_compress_data(enum zio_compress c, abd_t *src, abd_t **dst, size_t s_len,
 124     size_t d_len, uint8_t level)
 125 {
 126         size_t c_len;
 127         uint8_t complevel;
 128         zio_compress_info_t *ci = &zio_compress_table[c];
 129
 130         ASSERT3U(ci->ci_compress, !=, NULL);
 131         ASSERT3U(s_len, >, 0);
 132
 133         complevel = ci->ci_level;
 134
 135         if (c == ZIO_COMPRESS_ZSTD) {
 136                 /* If we don't know the level, we can't compress it */
 137                 if (level == ZIO_COMPLEVEL_INHERIT)
 138                         return (s_len);
 139
 140                 if (level == ZIO_COMPLEVEL_DEFAULT)
 141                         complevel = ZIO_ZSTD_LEVEL_DEFAULT;
 142                 else
 143                         complevel = level;
 144
 145                 ASSERT3U(complevel, !=, ZIO_COMPLEVEL_INHERIT);
 146         }
 147
 148         if (*dst == NULL)
 149                 *dst = abd_alloc_sametype(src, s_len);
 150
 151         c_len = ci->ci_compress(src, *dst, s_len, d_len, complevel);
 152
 153         if (c_len > d_len)
 154                 return (s_len);
 155
 156         return (c_len);
 157 }
 158
 159 int
 160 zio_decompress_data(enum zio_compress c, abd_t *src, abd_t *dst,
 161     size_t s_len, size_t d_len, uint8_t *level)
 162 {
 163         zio_compress_info_t *ci = &zio_compress_table[c];
 164         if ((uint_t)c >= ZIO_COMPRESS_FUNCTIONS || ci->ci_decompress == NULL)
 165                 return (SET_ERROR(EINVAL));
 166
 167         int err;
 168         if (ci->ci_decompress_level != NULL && level != NULL)
 169                 err = ci->ci_decompress_level(src, dst, s_len, d_len, level);
 170         else
 171                 err = ci->ci_decompress(src, dst, s_len, d_len, ci->ci_level);
 172
 173         /*
 174          * Decompression shouldn't fail, because we've already verified
 175          * the checksum.  However, for extra protection (e.g. against bitflips
 176          * in non-ECC RAM), we handle this error (and test it).
 177          */
 178         if (zio_decompress_fail_fraction != 0 &&
 179             random_in_range(zio_decompress_fail_fraction) == 0)
 180                 err = SET_ERROR(EINVAL);
 181
 182         return (err);
 183 }
 184
 185 int
 186 zio_compress_to_feature(enum zio_compress comp)
 187 {
 188         switch (comp) {
 189         case ZIO_COMPRESS_ZSTD:
 190                 return (SPA_FEATURE_ZSTD_COMPRESS);
 191         default:
 192                 break;
 193         }
 194         return (SPA_FEATURE_NONE);
 195 }