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
|
#include <linux/module.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
/*
* walks the btree of allocated inodes and find a hole.
*/
int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
struct btrfs_root *fs_root,
u64 dirid, u64 *objectid)
{
struct btrfs_path *path;
struct btrfs_key key;
int ret;
u64 hole_size = 0;
int slot = 0;
u64 last_ino = 0;
int start_found;
struct btrfs_leaf *l;
struct btrfs_root *root = fs_root->fs_info->inode_root;
struct btrfs_key search_key;
u64 search_start = dirid;
if (fs_root->fs_info->last_inode_alloc_dirid == dirid)
search_start = fs_root->fs_info->last_inode_alloc;
search_start = max(search_start, BTRFS_FIRST_FREE_OBJECTID);
search_key.objectid = search_start;
search_key.flags = 0;
btrfs_set_key_type(&search_key, BTRFS_INODE_MAP_ITEM_KEY);
search_key.offset = 0;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
start_found = 0;
ret = btrfs_search_slot(trans, root, &search_key, path, 0, 0);
if (ret < 0)
goto error;
if (path->slots[0] > 0)
path->slots[0]--;
while (1) {
l = btrfs_buffer_leaf(path->nodes[0]);
slot = path->slots[0];
if (slot >= btrfs_header_nritems(&l->header)) {
ret = btrfs_next_leaf(root, path);
if (ret == 0)
continue;
if (ret < 0)
goto error;
if (!start_found) {
*objectid = search_start;
start_found = 1;
goto found;
}
*objectid = last_ino > search_start ?
last_ino : search_start;
goto found;
}
btrfs_disk_key_to_cpu(&key, &l->items[slot].key);
if (key.objectid >= search_start) {
if (start_found) {
if (last_ino < search_start)
last_ino = search_start;
hole_size = key.objectid - last_ino;
if (hole_size > 0) {
*objectid = last_ino;
goto found;
}
}
}
start_found = 1;
last_ino = key.objectid + 1;
path->slots[0]++;
}
// FIXME -ENOSPC
found:
root->fs_info->last_inode_alloc = *objectid;
root->fs_info->last_inode_alloc_dirid = dirid;
btrfs_release_path(root, path);
btrfs_free_path(path);
BUG_ON(*objectid < search_start);
return 0;
error:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
int btrfs_insert_inode_map(struct btrfs_trans_handle *trans,
struct btrfs_root *fs_root,
u64 objectid, struct btrfs_key *location)
{
int ret = 0;
struct btrfs_path *path;
struct btrfs_inode_map_item *inode_item;
struct btrfs_key key;
struct btrfs_root *inode_root = fs_root->fs_info->inode_root;
key.objectid = objectid;
key.flags = 0;
btrfs_set_key_type(&key, BTRFS_INODE_MAP_ITEM_KEY);
key.offset = 0;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
ret = btrfs_insert_empty_item(trans, inode_root, path, &key,
sizeof(struct btrfs_inode_map_item));
if (ret)
goto out;
inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
path->slots[0], struct btrfs_inode_map_item);
btrfs_cpu_key_to_disk(&inode_item->key, location);
btrfs_mark_buffer_dirty(path->nodes[0]);
out:
btrfs_release_path(inode_root, path);
btrfs_free_path(path);
return ret;
}
int btrfs_lookup_inode_map(struct btrfs_trans_handle *trans,
struct btrfs_root *fs_root, struct btrfs_path *path,
u64 objectid, int mod)
{
int ret;
struct btrfs_key key;
int ins_len = mod < 0 ? -1 : 0;
int cow = mod != 0;
struct btrfs_root *inode_root = fs_root->fs_info->inode_root;
key.objectid = objectid;
key.flags = 0;
key.offset = 0;
btrfs_set_key_type(&key, BTRFS_INODE_MAP_ITEM_KEY);
ret = btrfs_search_slot(trans, inode_root, &key, path, ins_len, cow);
return ret;
}
|
