112 lines
2.7 KiB
C
112 lines
2.7 KiB
C
#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 %Lu %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;
|
|
}
|