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
|
// SPDX-License-Identifier: GPL-2.0+
/*
* BTRFS filesystem implementation for U-Boot
*
* 2017 Marek Behún, CZ.NIC, kabel@kernel.org
*/
#include "btrfs.h"
#include "disk-io.h"
static int verify_dir_item(struct btrfs_root *root,
struct extent_buffer *leaf,
struct btrfs_dir_item *dir_item)
{
u16 namelen = BTRFS_NAME_LEN;
u8 type = btrfs_dir_type(leaf, dir_item);
if (type == BTRFS_FT_XATTR)
namelen = XATTR_NAME_MAX;
if (btrfs_dir_name_len(leaf, dir_item) > namelen) {
fprintf(stderr, "invalid dir item name len: %u\n",
(unsigned)btrfs_dir_data_len(leaf, dir_item));
return 1;
}
/* BTRFS_MAX_XATTR_SIZE is the same for all dir items */
if ((btrfs_dir_data_len(leaf, dir_item) +
btrfs_dir_name_len(leaf, dir_item)) >
BTRFS_MAX_XATTR_SIZE(root->fs_info)) {
fprintf(stderr, "invalid dir item name + data len: %u + %u\n",
(unsigned)btrfs_dir_name_len(leaf, dir_item),
(unsigned)btrfs_dir_data_len(leaf, dir_item));
return 1;
}
return 0;
}
struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root,
struct btrfs_path *path,
const char *name, int name_len)
{
struct btrfs_dir_item *dir_item;
unsigned long name_ptr;
u32 total_len;
u32 cur = 0;
u32 this_len;
struct extent_buffer *leaf;
leaf = path->nodes[0];
dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item);
total_len = btrfs_item_size_nr(leaf, path->slots[0]);
if (verify_dir_item(root, leaf, dir_item))
return NULL;
while(cur < total_len) {
this_len = sizeof(*dir_item) +
btrfs_dir_name_len(leaf, dir_item) +
btrfs_dir_data_len(leaf, dir_item);
if (this_len > (total_len - cur)) {
fprintf(stderr, "invalid dir item size\n");
return NULL;
}
name_ptr = (unsigned long)(dir_item + 1);
if (btrfs_dir_name_len(leaf, dir_item) == name_len &&
memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0)
return dir_item;
cur += this_len;
dir_item = (struct btrfs_dir_item *)((char *)dir_item +
this_len);
}
return NULL;
}
struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct btrfs_path *path, u64 dir,
const char *name, int name_len,
int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
struct btrfs_key found_key;
struct extent_buffer *leaf;
key.objectid = dir;
key.type = BTRFS_DIR_ITEM_KEY;
key.offset = btrfs_name_hash(name, name_len);
ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow);
if (ret < 0)
return ERR_PTR(ret);
if (ret > 0) {
if (path->slots[0] == 0)
return NULL;
path->slots[0]--;
}
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != dir ||
found_key.type != BTRFS_DIR_ITEM_KEY ||
found_key.offset != key.offset)
return NULL;
return btrfs_match_dir_item_name(root, path, name, name_len);
}
int btrfs_iter_dir(struct btrfs_root *root, u64 ino,
btrfs_iter_dir_callback_t callback)
{
struct btrfs_path path;
struct btrfs_key key;
int ret;
btrfs_init_path(&path);
key.objectid = ino;
key.type = BTRFS_DIR_INDEX_KEY;
key.offset = 0;
ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
if (ret < 0)
return ret;
/* Should not happen */
if (ret == 0) {
ret = -EUCLEAN;
goto out;
}
if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) {
ret = btrfs_next_leaf(root, &path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
goto out;
}
}
do {
struct btrfs_dir_item *di;
btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
if (key.objectid != ino || key.type != BTRFS_DIR_INDEX_KEY)
break;
di = btrfs_item_ptr(path.nodes[0], path.slots[0],
struct btrfs_dir_item);
if (verify_dir_item(root, path.nodes[0], di)) {
ret = -EUCLEAN;
goto out;
}
ret = callback(root, path.nodes[0], di);
if (ret < 0)
goto out;
} while (!(ret = btrfs_next_item(root, &path)));
if (ret > 0)
ret = 0;
out:
btrfs_release_path(&path);
return ret;
}
|
