49
50
* we want the ability to take advantage of that hardware.
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52
* Of course, we don't want a checksum upgrade to invalidate existing
52
* data, so we store the checksum *function* in five bits of the DVA.
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* This gives us room for up to 32 different checksum functions.
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* data, so we store the checksum *function* in eight bits of the bp.
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* This gives us room for up to 256 different checksum functions.
55
56
* When writing a block, we always checksum it with the latest-and-greatest
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* checksum function of the appropriate strength. When reading a block,
57
58
* we compare the expected checksum against the actual checksum, which we
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* compute via the checksum function specified in the DVA encoding.
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* compute via the checksum function specified by BP_GET_CHECKSUM(bp).
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zio_checksum_info_t zio_checksum_table[ZIO_CHECKSUM_FUNCTIONS] = {
69
{{NULL, NULL}, 0, 0, "inherit"},
70
{{NULL, NULL}, 0, 0, "on"},
71
{{zio_checksum_off, zio_checksum_off}, 0, 0, "off"},
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{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, "label"},
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{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, "gang_header"},
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{{fletcher_2_native, fletcher_2_byteswap}, 0, 1, "zilog"},
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{{fletcher_2_native, fletcher_2_byteswap}, 0, 0, "fletcher2"},
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{{fletcher_4_native, fletcher_4_byteswap}, 1, 0, "fletcher4"},
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{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 0, "SHA256"},
70
{{NULL, NULL}, 0, 0, 0, "inherit"},
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{{NULL, NULL}, 0, 0, 0, "on"},
72
{{zio_checksum_off, zio_checksum_off}, 0, 0, 0, "off"},
73
{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, 0, "label"},
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{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 1, 0, "gang_header"},
75
{{fletcher_2_native, fletcher_2_byteswap}, 0, 1, 0, "zilog"},
76
{{fletcher_2_native, fletcher_2_byteswap}, 0, 0, 0, "fletcher2"},
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{{fletcher_4_native, fletcher_4_byteswap}, 1, 0, 0, "fletcher4"},
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{{zio_checksum_SHA256, zio_checksum_SHA256}, 1, 0, 1, "sha256"},
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{{fletcher_4_native, fletcher_4_byteswap}, 0, 1, 0, "zilog2"},
81
zio_checksum_select(uint8_t child, uint8_t parent)
83
zio_checksum_select(enum zio_checksum child, enum zio_checksum parent)
83
85
ASSERT(child < ZIO_CHECKSUM_FUNCTIONS);
84
86
ASSERT(parent < ZIO_CHECKSUM_FUNCTIONS);
99
zio_checksum_dedup_select(spa_t *spa, enum zio_checksum child,
100
enum zio_checksum parent)
102
ASSERT((child & ZIO_CHECKSUM_MASK) < ZIO_CHECKSUM_FUNCTIONS);
103
ASSERT((parent & ZIO_CHECKSUM_MASK) < ZIO_CHECKSUM_FUNCTIONS);
104
ASSERT(parent != ZIO_CHECKSUM_INHERIT && parent != ZIO_CHECKSUM_ON);
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if (child == ZIO_CHECKSUM_INHERIT)
109
if (child == ZIO_CHECKSUM_ON)
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return (spa_dedup_checksum(spa));
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if (child == (ZIO_CHECKSUM_ON | ZIO_CHECKSUM_VERIFY))
113
return (spa_dedup_checksum(spa) | ZIO_CHECKSUM_VERIFY);
115
ASSERT(zio_checksum_table[child & ZIO_CHECKSUM_MASK].ci_dedup ||
116
(child & ZIO_CHECKSUM_VERIFY) || child == ZIO_CHECKSUM_OFF);
97
122
* Set the external verifier for a gang block based on <vdev, offset, txg>,
98
123
* a tuple which is guaranteed to be unique for the life of the pool.
129
154
blkptr_t *bp = zio->io_bp;
130
155
uint64_t offset = zio->io_offset;
131
zio_block_tail_t *zbt = (zio_block_tail_t *)((char *)data + size) - 1;
132
156
zio_checksum_info_t *ci = &zio_checksum_table[checksum];
133
zio_cksum_t zbt_cksum;
135
159
ASSERT((uint_t)checksum < ZIO_CHECKSUM_FUNCTIONS);
136
160
ASSERT(ci->ci_func[0] != NULL);
165
if (checksum == ZIO_CHECKSUM_ZILOG2) {
166
zil_chain_t *zilc = data;
168
size = P2ROUNDUP_TYPED(zilc->zc_nused, ZIL_MIN_BLKSZ,
172
eck = (zio_eck_t *)((char *)data + size) - 1;
139
174
if (checksum == ZIO_CHECKSUM_GANG_HEADER)
140
zio_checksum_gang_verifier(&zbt->zbt_cksum, bp);
175
zio_checksum_gang_verifier(&eck->zec_cksum, bp);
141
176
else if (checksum == ZIO_CHECKSUM_LABEL)
142
zio_checksum_label_verifier(&zbt->zbt_cksum, offset);
177
zio_checksum_label_verifier(&eck->zec_cksum, offset);
144
bp->blk_cksum = zbt->zbt_cksum;
145
zbt->zbt_magic = ZBT_MAGIC;
146
ci->ci_func[0](data, size, &zbt_cksum);
147
zbt->zbt_cksum = zbt_cksum;
179
bp->blk_cksum = eck->zec_cksum;
180
eck->zec_magic = ZEC_MAGIC;
181
ci->ci_func[0](data, size, &cksum);
182
eck->zec_cksum = cksum;
149
184
ci->ci_func[0](data, size, &bp->blk_cksum);
154
zio_checksum_error(zio_t *zio)
189
zio_checksum_error(zio_t *zio, zio_bad_cksum_t *info)
156
191
blkptr_t *bp = zio->io_bp;
157
192
uint_t checksum = (bp == NULL ? zio->io_prop.zp_checksum :
158
193
(BP_IS_GANG(bp) ? ZIO_CHECKSUM_GANG_HEADER : BP_GET_CHECKSUM(bp)));
160
void *data = zio->io_data;
161
196
uint64_t size = (bp == NULL ? zio->io_size :
162
197
(BP_IS_GANG(bp) ? SPA_GANGBLOCKSIZE : BP_GET_PSIZE(bp)));
163
198
uint64_t offset = zio->io_offset;
164
zio_block_tail_t *zbt = (zio_block_tail_t *)((char *)data + size) - 1;
199
void *data = zio->io_data;
165
200
zio_checksum_info_t *ci = &zio_checksum_table[checksum];
166
201
zio_cksum_t actual_cksum, expected_cksum, verifier;
168
203
if (checksum >= ZIO_CHECKSUM_FUNCTIONS || ci->ci_func[0] == NULL)
209
if (checksum == ZIO_CHECKSUM_ZILOG2) {
210
zil_chain_t *zilc = data;
214
if (eck->zec_magic == ZEC_MAGIC)
215
nused = zilc->zc_nused;
216
else if (eck->zec_magic == BSWAP_64(ZEC_MAGIC))
217
nused = BSWAP_64(zilc->zc_nused);
224
size = P2ROUNDUP_TYPED(nused, ZIL_MIN_BLKSZ, uint64_t);
226
eck = (zio_eck_t *)((char *)data + size) - 1;
172
229
if (checksum == ZIO_CHECKSUM_GANG_HEADER)
173
230
zio_checksum_gang_verifier(&verifier, bp);
174
231
else if (checksum == ZIO_CHECKSUM_LABEL)
177
234
verifier = bp->blk_cksum;
179
byteswap = (zbt->zbt_magic == BSWAP_64(ZBT_MAGIC));
236
byteswap = (eck->zec_magic == BSWAP_64(ZEC_MAGIC));
182
239
byteswap_uint64_array(&verifier, sizeof (zio_cksum_t));
184
expected_cksum = zbt->zbt_cksum;
185
zbt->zbt_cksum = verifier;
241
expected_cksum = eck->zec_cksum;
242
eck->zec_cksum = verifier;
186
243
ci->ci_func[byteswap](data, size, &actual_cksum);
187
zbt->zbt_cksum = expected_cksum;
244
eck->zec_cksum = expected_cksum;
190
247
byteswap_uint64_array(&expected_cksum,
196
253
ci->ci_func[byteswap](data, size, &actual_cksum);
256
info->zbc_expected = expected_cksum;
257
info->zbc_actual = actual_cksum;
258
info->zbc_checksum_name = ci->ci_name;
259
info->zbc_byteswapped = byteswap;
260
info->zbc_injected = 0;
261
info->zbc_has_cksum = 1;
199
263
if (!ZIO_CHECKSUM_EQUAL(actual_cksum, expected_cksum))
202
if (zio_injection_enabled && !zio->io_error)
203
return (zio_handle_fault_injection(zio, ECKSUM));
266
if (zio_injection_enabled && !zio->io_error &&
267
(error = zio_handle_fault_injection(zio, ECKSUM)) != 0) {
269
info->zbc_injected = 1;