static struct dentry *btrfs_get_parent(struct dentry *child)
{
struct inode *dir = d_inode(child);
struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
struct btrfs_root *root = BTRFS_I(dir)->root;
struct btrfs_path *path;
struct extent_buffer *leaf;
struct btrfs_root_ref *ref;
struct btrfs_key key;
struct btrfs_key found_key;
int ret;
path = btrfs_alloc_path();
if (!path)
return ERR_PTR(-ENOMEM);
if (btrfs_ino(BTRFS_I(dir)) == BTRFS_FIRST_FREE_OBJECTID) {
key.objectid = root->root_key.objectid;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = (u64)-1;
root = fs_info->tree_root;
} else {
key.objectid = btrfs_ino(BTRFS_I(dir));
key.type = BTRFS_INODE_REF_KEY;
key.offset = (u64)-1;
}
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto fail;
BUG_ON(ret == 0); /* Key with offset of -1 found */
if (path->slots[0] == 0) {
ret = -ENOENT;
goto fail;
}
path->slots[0]--;
leaf = path->nodes[0];
btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
if (found_key.objectid != key.objectid || found_key.type != key.type) {
ret = -ENOENT;
goto fail;
}
if (found_key.type == BTRFS_ROOT_BACKREF_KEY) {
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_root_ref);
key.objectid = btrfs_root_ref_dirid(leaf, ref);
} else {
static void print_root_ref(struct extent_buffer *leaf, int slot, char *tag)
{
struct btrfs_root_ref *ref;
char namebuf[BTRFS_NAME_LEN];
int namelen;
ref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
namelen = btrfs_root_ref_name_len(leaf, ref);
read_extent_buffer(leaf, namebuf, (unsigned long)(ref + 1), namelen);
printf("\t\troot %s key dirid %llu sequence %llu name %.*s\n", tag,
(unsigned long long)btrfs_root_ref_dirid(leaf, ref),
(unsigned long long)btrfs_root_ref_sequence(leaf, ref),
namelen, namebuf);
}
int btrfs_del_root_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *tree_root,
u64 root_id, u64 ref_id, u64 dirid, u64 *sequence,
const char *name, int name_len)
{
struct btrfs_path *path;
struct btrfs_root_ref *ref;
struct extent_buffer *leaf;
struct btrfs_key key;
unsigned long ptr;
int err = 0;
int ret;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = root_id;
key.type = BTRFS_ROOT_BACKREF_KEY;
key.offset = ref_id;
again:
ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
BUG_ON(ret < 0);
if (ret == 0) {
leaf = path->nodes[0];
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_root_ref);
WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid);
WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len);
ptr = (unsigned long)(ref + 1);
WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len));
*sequence = btrfs_root_ref_sequence(leaf, ref);
ret = btrfs_del_item(trans, tree_root, path);
if (ret) {
err = ret;
goto out;
}
} else
