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
|
/*
* readwrite.c
*
* Copyright (c) 2007-2008 Joern Engel <joern@logfs.org>
*
* License: GPL version 2
*/
#include <asm/types.h>
#include <errno.h>
#include "btree.h"
#include "kerncompat.h"
#include "logfs_abi.h"
#include "logfs.h"
static unsigned long __get_bits(u64 val, int skip, int no)
{
u64 ret = val;
ret >>= skip * no;
ret <<= 64 - no;
ret >>= 64 - no;
return ret;
}
static unsigned long get_bits(struct super_block *sb, u64 bix, u8 level)
{
return __get_bits(bix, level, sb->blocksize_bits - 3);
}
static inline int child_no(struct super_block *sb, u64 bix)
{
return bix & ((sb->blocksize / sizeof(__be64)) - 1);
}
struct inode *find_or_create_inode(struct super_block *sb, u64 ino)
{
struct inode *inode;
int err;
inode = btree_lookup64(&sb->ino_tree, ino);
if (!inode) {
inode = zalloc(sizeof(*inode) + sb->blocksize);
if (!inode)
return NULL;
err = btree_insert64(&sb->ino_tree, ino, inode);
if (err)
return NULL;
}
return inode;
}
static __be64 *find_or_create_block(struct super_block *sb, struct inode *inode,
u64 bix, u8 level)
{
__be64 *block;
struct btree_head64 *tree = &inode->block_tree[level];
int err;
block = btree_lookup64(tree, bix);
if (!block) {
block = zalloc(sb->blocksize);
if (!block)
return NULL;
err = btree_insert64(tree, bix, block);
if (err)
return NULL;
}
return block;
}
static int write_direct(struct super_block *sb, struct inode *inode, u64 ino,
u64 bix, u8 type, void *buf)
{
s64 ofs;
ofs = logfs_segment_write(sb, buf, type, ino, bix, 0);
if (ofs < 0)
return ofs;
inode->di.di_data[bix] = cpu_to_be64(ofs);
return 0;
}
static u64 bixmask(struct super_block *sb, u8 level)
{
if (level == 0)
return 0;
return (1 << ((sb->blocksize_bits - 3) * level)) - 1;
}
static int write_loop(struct super_block *sb, struct inode *inode, u64 ino,
u64 bix, u8 level, u8 type, void *buf)
{
u64 parent_bix;
__be64 *iblock;
s64 ofs;
parent_bix = bix | bixmask(sb, level + 1);
iblock = find_or_create_block(sb, inode, parent_bix, level + 1);
if (!iblock)
return -ENOMEM;
ofs = logfs_segment_write(sb, buf, type, ino, bix, level);
if (ofs < 0)
return ofs;
iblock[get_bits(sb, bix, level)] = cpu_to_be64(ofs);
return 0;
}
static inline u64 maxbix(u8 height)
{
return 1ULL << (LOGFS_BLOCK_BITS * height);
}
static void grow_inode(struct inode *inode, u64 bix, u8 level)
{
if (level != 0)
return;
while (bix > maxbix(inode->di.di_height))
inode->di.di_height++;
}
int logfs_file_write(struct super_block *sb, u64 ino, u64 bix, u8 level,
u8 type, void *buf)
{
struct inode *inode;
inode = find_or_create_inode(sb, ino);
if (!inode)
return -ENOMEM;
if (level == 0 && bix < I0_BLOCKS)
return write_direct(sb, inode, ino, bix, type, buf);
grow_inode(inode, bix, level);
return write_loop(sb, inode, ino, bix, level, type, buf);
}
int logfs_file_flush(struct super_block *sb, u64 ino)
{
struct btree_head64 *tree;
struct inode *inode;
__be64 *iblock;
s64 ofs;
u64 bix;
u8 level;
int err;
inode = find_or_create_inode(sb, ino);
BUG_ON(!inode);
if (inode->di.di_height == 0)
return 0;
for (level = 1; level < inode->di.di_height; level++) {
tree = &inode->block_tree[level];
for (;;) {
bix = btree_last64(tree);
iblock = btree_remove64(tree, bix);
if (!iblock)
break;
err = logfs_file_write(sb, ino, bix, level, OBJ_BLOCK,
iblock);
if (err)
return err;
free(iblock);
}
}
BUG_ON(level != inode->di.di_height);
tree = &inode->block_tree[level];
bix = btree_last64(tree);
iblock = btree_remove64(tree, bix);
BUG_ON(!iblock);
ofs = logfs_segment_write(sb, iblock, OBJ_BLOCK, ino, bix, level);
if (ofs < 0)
return ofs;
inode->di.di_data[INDIRECT_INDEX] = cpu_to_be64(ofs);
return 0;
}
|
