1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
* 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
static uint64_t zfs_crc64_table[256];
static void
zfs_init_crc(void)
{
int i, j;
uint64_t *ct;
/*
* Calculate the crc64 table (used for the zap hash
* function).
*/
if (zfs_crc64_table[128] != ZFS_CRC64_POLY) {
memset(zfs_crc64_table, 0, sizeof(zfs_crc64_table));
for (i = 0; i < 256; i++)
for (ct = zfs_crc64_table + i, *ct = i, j = 8; j > 0; j--)
*ct = (*ct >> 1) ^ (-(*ct & 1) & ZFS_CRC64_POLY);
}
}
static void
zio_checksum_off(const void *buf, uint64_t size, zio_cksum_t *zcp)
{
ZIO_SET_CHECKSUM(zcp, 0, 0, 0, 0);
}
/*
* Signature for checksum functions.
*/
typedef void zio_checksum_t(const void *data, uint64_t size, zio_cksum_t *zcp);
/*
* Information about each checksum function.
*/
typedef struct zio_checksum_info {
zio_checksum_t *ci_func[2]; /* checksum function for each byteorder */
int ci_correctable; /* number of correctable bits */
int ci_zbt; /* uses zio block tail? */
const char *ci_name; /* descriptive name */
} zio_checksum_info_t;
#include "fletcher.c"
#include "sha256.c"
static zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = {
{{NULL, NULL}, 0, 0, "inherit"},
{{NULL, NULL}, 0, 0, "on"},
{{zio_checksum_off, zio_checksum_off}, 0, 0, "off"},
{{zio_checksum_SHA256, NULL}, 1, 1, "label"},
{{zio_checksum_SHA256, NULL}, 1, 1, "gang_header"},
{{fletcher_2_native, NULL}, 0, 1, "zilog"},
{{fletcher_2_native, NULL}, 0, 0, "fletcher2"},
{{fletcher_4_native, NULL}, 1, 0, "fletcher4"},
{{zio_checksum_SHA256, NULL}, 1, 0, "SHA256"},
};
/*
* Common signature for all zio compress/decompress functions.
*/
typedef size_t zio_compress_func_t(void *src, void *dst,
size_t s_len, size_t d_len, int);
typedef int zio_decompress_func_t(void *src, void *dst,
size_t s_len, size_t d_len, int);
/*
* Information about each compression function.
*/
typedef struct zio_compress_info {
zio_compress_func_t *ci_compress; /* compression function */
zio_decompress_func_t *ci_decompress; /* decompression function */
int ci_level; /* level parameter */
const char *ci_name; /* algorithm name */
} zio_compress_info_t;
#include "lzjb.c"
/*
* Compression vectors.
*/
static zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = {
{NULL, NULL, 0, "inherit"},
{NULL, NULL, 0, "on"},
{NULL, NULL, 0, "uncompressed"},
{NULL, lzjb_decompress, 0, "lzjb"},
{NULL, NULL, 0, "empty"},
{NULL, NULL, 1, "gzip-1"},
{NULL, NULL, 2, "gzip-2"},
{NULL, NULL, 3, "gzip-3"},
{NULL, NULL, 4, "gzip-4"},
{NULL, NULL, 5, "gzip-5"},
{NULL, NULL, 6, "gzip-6"},
{NULL, NULL, 7, "gzip-7"},
{NULL, NULL, 8, "gzip-8"},
{NULL, NULL, 9, "gzip-9"},
};
static int
zio_checksum_error(const blkptr_t *bp, void *data)
{
zio_cksum_t zc = bp->blk_cksum;
unsigned int checksum = BP_GET_CHECKSUM(bp);
uint64_t size = BP_GET_PSIZE(bp);
zio_block_tail_t *zbt = (zio_block_tail_t *)((char *)data + size) - 1;
zio_checksum_info_t *ci = &zio_checksum_table[checksum];
zio_cksum_t actual_cksum, expected_cksum;
if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL)
return (EINVAL);
if (ci->ci_zbt) {
expected_cksum = zbt->zbt_cksum;
zbt->zbt_cksum = zc;
ci->ci_func[0](data, size, &actual_cksum);
zbt->zbt_cksum = expected_cksum;
zc = expected_cksum;
} else {
/* ASSERT(!BP_IS_GANG(bp)); */
ci->ci_func[0](data, size, &actual_cksum);
}
if (!ZIO_CHECKSUM_EQUAL(actual_cksum, zc)) {
/*printf("ZFS: read checksum failed\n");*/
return (EIO);
}
return (0);
}
static 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); */
if (!ci->ci_decompress) {
printf("ZFS: unsupported compression algorithm %u\n", cpfunc);
return (EIO);
}
return (ci->ci_decompress(src, dest, srcsize, destsize, ci->ci_level));
}
static uint64_t
zap_hash(uint64_t salt, const char *name)
{
const uint8_t *cp;
uint8_t c;
uint64_t crc = salt;
/*ASSERT(crc != 0);*/
/*ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY);*/
for (cp = (const uint8_t *)name; (c = *cp) != '\0'; cp++)
crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ c) & 0xFF];
/*
* Only use 28 bits, since we need 4 bits in the cookie for the
* collision differentiator. We MUST use the high bits, since
* those are the onces that we first pay attention to when
* chosing the bucket.
*/
crc &= ~((1ULL << (64 - ZAP_HASHBITS)) - 1);
return (crc);
}
|
