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
|
/*
* segment.c
*
* Copyright (c) 2007-2008 Joern Engel <joern@logfs.org>
*
* License: GPL version 2
*/
#include <asm/types.h>
#include <errno.h>
#include "kerncompat.h"
#include "logfs_abi.h"
#include "logfs.h"
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MIN(a, b) ((a) < (b) ? (a) : (b))
static inline void hexdump(const char *prefix, void *buf, size_t len)
{
unsigned char *c = buf;
int i;
printf("%s", prefix);
for (i = 0; i < len; i++) {
printf("%02x ", c[i]);
if (i % 8 == 7)
printf(" ");
if (i % 16 == 15)
printf("\n");
}
printf("\n");
}
static void copybuf(struct logfs_area *area, void *buf, size_t len)
{
memcpy(area->buf + area->used_bytes, buf, len);
area->used_bytes += len;
}
u32 get_segment(struct super_block *sb)
{
u64 ofs;
u32 segno;
int err;
do {
segno = sb->lastseg;
ofs = (u64)segno * sb->segsize;
sb->lastseg += 1;
if (sb->lastseg > sb->no_segs)
fail("no more free segments");
err = sb->dev_ops->erase(sb, ofs, sb->segsize);
if (err) {
/* bad segment */
sb->segment_entry[segno].ec_level = cpu_to_be32(BADSEG);
sb->segment_entry[segno].valid = cpu_to_be32(RESERVED);
printf("Bad block at 0x%llx\n", ofs);
}
} while (err);
return segno;
}
static void __init_area(struct super_block *sb, struct logfs_area *area,
u8 level)
{
struct logfs_segment_header *sh = area->buf;
memset(area->buf, 0xff, sb->segsize);
area->segno = get_segment(sb);
area->used_bytes = sizeof(*sh);
sh->pad = 0;
sh->type = SEG_OSTORE;
sh->level = level;
sh->segno = cpu_to_be32(area->segno);
sh->ec = cpu_to_be32(1);
sh->gec = cpu_to_be64(area->segno);
sh->crc = logfs_crc32(sh, LOGFS_SEGMENT_HEADERSIZE, 4);
}
static void init_area(struct super_block *sb, struct logfs_area *area,
u8 level)
{
if (area->buf)
return;
area->buf = malloc(sb->segsize);
__init_area(sb, area, level);
}
static int finish_area(struct super_block *sb, struct logfs_area *area,
int final, u8 level)
{
u64 ofs = (u64)area->segno * sb->segsize;
int err;
err = sb->dev_ops->write(sb, ofs, sb->segsize, area->buf);
if (err)
return err;
sb->segment_entry[area->segno].ec_level = ec_level(1, level);
sb->segment_entry[area->segno].valid =
cpu_to_be32(area->used_bytes - LOGFS_SEGMENT_HEADERSIZE);
if (final)
return 0;
__init_area(sb, area, level);
return 0;
}
static int grow_inode(struct super_block *sb, u64 ino, size_t len)
{
struct inode *inode = find_or_create_inode(sb, ino);
if (!inode)
return -ENOMEM;
inode->di.di_used_bytes =
cpu_to_be64(len + be64_to_cpu(inode->di.di_used_bytes));
sb->used_bytes += len;
return 0;
}
static int obj_len(struct super_block *sb, int obj_type)
{
switch (obj_type) {
case OBJ_DENTRY:
return sizeof(struct logfs_disk_dentry);
case OBJ_INODE:
return sizeof(struct logfs_disk_inode);
case OBJ_BLOCK:
return sb->blocksize;
default:
BUG();
}
}
s64 logfs_segment_write(struct super_block *sb, void *buf, u8 type,
u64 ino, u64 bix, u8 level)
{
struct logfs_object_header oh;
struct logfs_area *area;
int err;
s64 ofs;
u16 len = obj_len(sb, type);
if (ino == LOGFS_INO_MASTER)
level += LOGFS_MAX_LEVELS;
area = sb->area + level;
memset(&oh, 0, sizeof(oh));
oh.len = cpu_to_be16(len);
oh.type = type;
oh.compr = COMPR_NONE;
oh.ino = cpu_to_be64(ino);
oh.bix = cpu_to_be64(bix);
oh.crc = logfs_crc32(&oh, LOGFS_OBJECT_HEADERSIZE - 4, 4);
oh.data_crc = logfs_crc32(buf, len, 0);
init_area(sb, area, level);
if (area->used_bytes + sizeof(oh) + sb->blocksize > sb->segsize) {
err = finish_area(sb, area, 0, level);
if (err)
return err;
}
ofs = area->segno * sb->segsize + area->used_bytes;
copybuf(area, &oh, sizeof(oh));
copybuf(area, buf, len);
err = grow_inode(sb, ino, sizeof(oh) + len);
if (err)
return err;
return ofs;
}
int flush_segments(struct super_block *sb)
{
struct logfs_area *area;
int i, err;
for (i = 0; i < LOGFS_NO_AREAS; i++) {
area = sb->area + i;
if (area->buf) {
err = finish_area(sb, area, 1, i);
if (err)
return err;
}
}
return 0;
}
|
