int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info,
struct btrfs_path *path,
iterate_extent_inodes_t *iterate, void *ctx)
{
int ret;
u64 extent_item_pos;
u64 flags = 0;
struct btrfs_key found_key;
int search_commit_root = path->search_commit_root;
ret = extent_from_logical(fs_info, logical, path, &found_key, &flags);
btrfs_release_path(path);
if (ret < 0)
return ret;
if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)
return -EINVAL;
extent_item_pos = logical - found_key.objectid;
ret = iterate_extent_inodes(fs_info, found_key.objectid,
extent_item_pos, search_commit_root,
iterate, ctx);
return ret;
}
static int __iter_shared_inline_ref_inodes(struct btrfs_fs_info *fs_info,
u64 logical, u64 inum,
u64 extent_data_item_offset,
u64 extent_offset,
struct btrfs_path *path,
struct list_head *data_refs,
iterate_extent_inodes_t *iterate,
void *ctx)
{
u64 ref_root;
u32 item_size;
struct btrfs_key key;
struct extent_buffer *eb;
struct btrfs_extent_item *ei;
struct btrfs_extent_inline_ref *eiref;
struct __data_ref *ref;
int ret;
int type;
int last;
unsigned long ptr = 0;
WARN_ON(!list_empty(data_refs));
ret = extent_from_logical(fs_info, logical, path, &key);
if (ret & BTRFS_EXTENT_FLAG_DATA)
ret = -EIO;
if (ret < 0)
goto out;
eb = path->nodes[0];
ei = btrfs_item_ptr(eb, path->slots[0], struct btrfs_extent_item);
item_size = btrfs_item_size_nr(eb, path->slots[0]);
ret = 0;
ref_root = 0;
/*
* as done in iterate_extent_inodes, we first build a list of refs to
* iterate, then free the path and then iterate them to avoid deadlocks.
*/
do {
last = __get_extent_inline_ref(&ptr, eb, ei, item_size,
&eiref, &type);
if (last < 0) {
ret = last;
goto out;
}
if (type == BTRFS_TREE_BLOCK_REF_KEY ||
type == BTRFS_SHARED_BLOCK_REF_KEY) {
ref_root = btrfs_extent_inline_ref_offset(eb, eiref);
ret = __data_list_add(data_refs, inum,
extent_data_item_offset,
ref_root);
}
} while (!ret && !last);
btrfs_release_path(path);
if (ref_root == 0) {
printk(KERN_ERR "btrfs: failed to find tree block ref "
"for shared data backref %llu\n", logical);
WARN_ON(1);
ret = -EIO;
}
out:
while (!list_empty(data_refs)) {
ref = list_first_entry(data_refs, struct __data_ref, list);
list_del(&ref->list);
if (!ret)
ret = iterate(ref->inum, extent_offset +
ref->extent_data_item_offset,
ref->root, ctx);
kfree(ref);
}
return ret;
}