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
|
#include <linux/module.h>
#include "ctree.h"
#include "disk-io.h"
#include "print-tree.h"
int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
struct btrfs_root_item *item, struct btrfs_key *key)
{
struct btrfs_path *path;
struct btrfs_key search_key;
struct btrfs_leaf *l;
int ret;
int slot;
search_key.objectid = objectid;
search_key.flags = (u32)-1;
search_key.offset = (u32)-1;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
if (ret < 0)
goto out;
BUG_ON(ret == 0);
l = btrfs_buffer_leaf(path->nodes[0]);
BUG_ON(path->slots[0] == 0);
slot = path->slots[0] - 1;
if (btrfs_disk_key_objectid(&l->items[slot].key) != objectid) {
ret = 1;
goto out;
}
memcpy(item, btrfs_item_ptr(l, slot, struct btrfs_root_item),
sizeof(*item));
btrfs_disk_key_to_cpu(key, &l->items[slot].key);
ret = 0;
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_root_item
*item)
{
struct btrfs_path *path;
struct btrfs_leaf *l;
int ret;
int slot;
struct btrfs_root_item *update_item;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
ret = btrfs_search_slot(trans, root, key, path, 0, 1);
if (ret < 0)
goto out;
BUG_ON(ret != 0);
l = btrfs_buffer_leaf(path->nodes[0]);
slot = path->slots[0];
update_item = btrfs_item_ptr(l, slot, struct btrfs_root_item);
btrfs_memcpy(root, l, update_item, item, sizeof(*item));
btrfs_mark_buffer_dirty(path->nodes[0]);
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_key *key, struct btrfs_root_item
*item)
{
int ret;
ret = btrfs_insert_item(trans, root, key, item, sizeof(*item));
BUG_ON(ret);
return ret;
}
int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_key *key)
{
struct btrfs_path *path;
int ret;
u32 refs;
struct btrfs_root_item *ri;
path = btrfs_alloc_path();
BUG_ON(!path);
btrfs_init_path(path);
ret = btrfs_search_slot(trans, root, key, path, -1, 1);
if (ret < 0)
goto out;
BUG_ON(ret != 0);
ri = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
path->slots[0], struct btrfs_root_item);
refs = btrfs_root_refs(ri);
BUG_ON(refs == 0);
if (refs == 1) {
ret = btrfs_del_item(trans, root, path);
} else {
btrfs_set_root_refs(ri, refs - 1);
printk("ref now %u root %llu %Lu %u\n", refs -1, key->objectid, key->offset, key->flags);
mark_buffer_dirty(path->nodes[0]);
}
out:
btrfs_release_path(root, path);
btrfs_free_path(path);
return ret;
}
|
