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
194
195
196
197
198
199
200
201
202
203
204
205
206
|
#include <errno.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <uuid/uuid.h>
#include "ccan/ilog/ilog.h"
#include "bcache-ondisk.h"
#include "libbcache.h"
#include "crypto.h"
void __do_write_sb(int fd, void *sb, size_t bytes)
{
char zeroes[SB_SECTOR << 9] = {0};
/* Zero start of disk */
if (pwrite(fd, zeroes, SB_SECTOR << 9, 0) != SB_SECTOR << 9) {
perror("write error trying to zero start of disk\n");
exit(EXIT_FAILURE);
}
/* Write superblock */
if (pwrite(fd, sb, bytes, SB_SECTOR << 9) != bytes) {
perror("write error trying to write superblock\n");
exit(EXIT_FAILURE);
}
fsync(fd);
close(fd);
}
#define do_write_sb(_fd, _sb) \
__do_write_sb(_fd, _sb, ((void *) __bset_bkey_last(_sb)) - (void *) _sb);
void bcache_format(struct dev_opts *devs, size_t nr_devs,
unsigned block_size,
unsigned btree_node_size,
unsigned meta_csum_type,
unsigned data_csum_type,
unsigned compression_type,
const char *passphrase,
unsigned meta_replicas,
unsigned data_replicas,
unsigned on_error_action,
char *label,
uuid_le uuid)
{
struct cache_sb *sb;
struct dev_opts *i;
/* calculate block size: */
if (!block_size)
for (i = devs; i < devs + nr_devs; i++)
block_size = max(block_size,
get_blocksize(i->dev, i->fd));
/* calculate bucket sizes: */
for (i = devs; i < devs + nr_devs; i++) {
if (!i->size)
i->size = get_size(i->dev, i->fd);
if (!i->bucket_size) {
u64 bytes = i->size << 9;
if (bytes < 1 << 20) /* 1M device - 256 4k buckets*/
i->bucket_size = rounddown_pow_of_two(bytes >> 17);
else
/* Max 1M bucket at around 256G */
i->bucket_size = 8 << min((ilog2(bytes >> 20) / 2), 9U);
}
if (i->bucket_size < block_size)
die("Bucket size cannot be smaller than block size");
i->nbuckets = i->size / i->bucket_size;
i->first_bucket = (23 / i->bucket_size) + 3;
if (i->nbuckets < 1 << 7)
die("Not enough buckets: %llu, need %u",
i->nbuckets, 1 << 7);
}
/* calculate btree node size: */
if (!btree_node_size) {
/* 256k default btree node size */
btree_node_size = 512;
for (i = devs; i < devs + nr_devs; i++)
btree_node_size = min(btree_node_size, i->bucket_size);
}
sb = calloc(1, sizeof(*sb) + sizeof(struct cache_member) * nr_devs);
sb->offset = __cpu_to_le64(SB_SECTOR);
sb->version = __cpu_to_le64(BCACHE_SB_VERSION_CDEV_V3);
sb->magic = BCACHE_MAGIC;
sb->block_size = __cpu_to_le16(block_size);
sb->user_uuid = uuid;
sb->nr_in_set = nr_devs;
uuid_generate(sb->set_uuid.b);
if (label)
strncpy((char *) sb->label, label, sizeof(sb->label));
/*
* don't have a userspace crc32c implementation handy, just always use
* crc64
*/
SET_CACHE_SB_CSUM_TYPE(sb, BCH_CSUM_CRC64);
SET_CACHE_SET_META_CSUM_TYPE(sb, meta_csum_type);
SET_CACHE_SET_DATA_CSUM_TYPE(sb, data_csum_type);
SET_CACHE_SET_COMPRESSION_TYPE(sb, compression_type);
SET_CACHE_SET_BTREE_NODE_SIZE(sb, btree_node_size);
SET_CACHE_SET_META_REPLICAS_WANT(sb, meta_replicas);
SET_CACHE_SET_META_REPLICAS_HAVE(sb, meta_replicas);
SET_CACHE_SET_DATA_REPLICAS_WANT(sb, data_replicas);
SET_CACHE_SET_DATA_REPLICAS_HAVE(sb, data_replicas);
SET_CACHE_SET_ERROR_ACTION(sb, on_error_action);
if (passphrase) {
struct bcache_key key;
struct bcache_disk_key disk_key;
derive_passphrase(&key, passphrase);
disk_key_init(&disk_key);
disk_key_encrypt(&disk_key, &key);
memcpy(sb->encryption_key, &disk_key, sizeof(disk_key));
SET_CACHE_SET_ENCRYPTION_TYPE(sb, 1);
SET_CACHE_SET_ENCRYPTION_KEY(sb, 1);
memzero_explicit(&disk_key, sizeof(disk_key));
memzero_explicit(&key, sizeof(key));
}
for (i = devs; i < devs + nr_devs; i++) {
struct cache_member *m = sb->members + (i - devs);
uuid_generate(m->uuid.b);
m->nbuckets = __cpu_to_le64(i->nbuckets);
m->first_bucket = __cpu_to_le16(i->first_bucket);
m->bucket_size = __cpu_to_le16(i->bucket_size);
SET_CACHE_TIER(m, i->tier);
SET_CACHE_REPLACEMENT(m, i->replacement_policy);
SET_CACHE_DISCARD(m, i->discard);
}
sb->u64s = __cpu_to_le16(bch_journal_buckets_offset(sb));
for (i = devs; i < devs + nr_devs; i++) {
struct cache_member *m = sb->members + (i - devs);
char uuid_str[40], set_uuid_str[40];
sb->disk_uuid = m->uuid;
sb->nr_this_dev = i - devs;
sb->csum = __cpu_to_le64(__csum_set(sb, __le16_to_cpu(sb->u64s),
CACHE_SB_CSUM_TYPE(sb)));
uuid_unparse(sb->disk_uuid.b, uuid_str);
uuid_unparse(sb->user_uuid.b, set_uuid_str);
printf("UUID: %s\n"
"Set UUID: %s\n"
"version: %u\n"
"nbuckets: %llu\n"
"block_size: %u\n"
"bucket_size: %u\n"
"nr_in_set: %u\n"
"nr_this_dev: %u\n"
"first_bucket: %u\n",
uuid_str, set_uuid_str,
(unsigned) sb->version,
__le64_to_cpu(m->nbuckets),
__le16_to_cpu(sb->block_size),
__le16_to_cpu(m->bucket_size),
sb->nr_in_set,
sb->nr_this_dev,
__le16_to_cpu(m->first_bucket));
do_write_sb(i->fd, sb);
}
free(sb);
}
void bcache_super_read(const char *path, struct cache_sb *sb)
{
int fd = open(path, O_RDONLY);
if (fd < 0)
die("couldn't open %s", path);
if (pread(fd, sb, sizeof(*sb), SB_SECTOR << 9) != sizeof(*sb))
die("error reading superblock");
if (memcmp(&sb->magic, &BCACHE_MAGIC, sizeof(sb->magic)))
die("not a bcache superblock");
}
|
