/* * add all currently queued delayed refs from this head whose seq nr is * smaller or equal that seq to the list */ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq, struct list_head *prefs, u64 *total_refs) { struct btrfs_delayed_extent_op *extent_op = head->extent_op; struct rb_node *n = &head->node.rb_node; struct btrfs_key key; struct btrfs_key op_key = {0}; int sgn; int ret = 0; if (extent_op && extent_op->update_key) btrfs_disk_key_to_cpu(&op_key, &extent_op->key); spin_lock(&head->lock); n = rb_first(&head->ref_root); while (n) { struct btrfs_delayed_ref_node *node; node = rb_entry(n, struct btrfs_delayed_ref_node, rb_node); n = rb_next(n); if (node->seq > seq) continue; switch (node->action) { case BTRFS_ADD_DELAYED_EXTENT: case BTRFS_UPDATE_DELAYED_HEAD: WARN_ON(1); continue; case BTRFS_ADD_DELAYED_REF: sgn = 1; break; case BTRFS_DROP_DELAYED_REF: sgn = -1; break; default: BUG_ON(1); } *total_refs += (node->ref_mod * sgn); switch (node->type) { case BTRFS_TREE_BLOCK_REF_KEY: { struct btrfs_delayed_tree_ref *ref; ref = btrfs_delayed_node_to_tree_ref(node); ret = __add_prelim_ref(prefs, ref->root, &op_key, ref->level + 1, 0, node->bytenr, node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_SHARED_BLOCK_REF_KEY: { struct btrfs_delayed_tree_ref *ref; ref = btrfs_delayed_node_to_tree_ref(node); ret = __add_prelim_ref(prefs, ref->root, NULL, ref->level + 1, ref->parent, node->bytenr, node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_delayed_data_ref *ref; ref = btrfs_delayed_node_to_data_ref(node); key.objectid = ref->objectid; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = ref->offset; ret = __add_prelim_ref(prefs, ref->root, &key, 0, 0, node->bytenr, node->ref_mod * sgn, GFP_ATOMIC); break; } case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_delayed_data_ref *ref; ref = btrfs_delayed_node_to_data_ref(node); key.objectid = ref->objectid; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = ref->offset; ret = __add_prelim_ref(prefs, ref->root, &key, 0, ref->parent, node->bytenr, node->ref_mod * sgn, GFP_ATOMIC); break; } default: WARN_ON(1); } if (ret) break; } spin_unlock(&head->lock); return ret; }
/* * add all inline backrefs for bytenr to the list */ static int __add_inline_refs(struct btrfs_fs_info *fs_info, struct btrfs_path *path, u64 bytenr, int *info_level, struct list_head *prefs, u64 *total_refs) { int ret = 0; int slot; struct extent_buffer *leaf; struct btrfs_key key; struct btrfs_key found_key; unsigned long ptr; unsigned long end; struct btrfs_extent_item *ei; u64 flags; u64 item_size; /* * enumerate all inline refs */ leaf = path->nodes[0]; slot = path->slots[0]; item_size = btrfs_item_size_nr(leaf, slot); BUG_ON(item_size < sizeof(*ei)); ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); flags = btrfs_extent_flags(leaf, ei); *total_refs += btrfs_extent_refs(leaf, ei); btrfs_item_key_to_cpu(leaf, &found_key, slot); ptr = (unsigned long)(ei + 1); end = (unsigned long)ei + item_size; if (found_key.type == BTRFS_EXTENT_ITEM_KEY && flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { struct btrfs_tree_block_info *info; info = (struct btrfs_tree_block_info *)ptr; *info_level = btrfs_tree_block_level(leaf, info); ptr += sizeof(struct btrfs_tree_block_info); BUG_ON(ptr > end); } else if (found_key.type == BTRFS_METADATA_ITEM_KEY) { *info_level = found_key.offset; } else { BUG_ON(!(flags & BTRFS_EXTENT_FLAG_DATA)); } while (ptr < end) { struct btrfs_extent_inline_ref *iref; u64 offset; int type; iref = (struct btrfs_extent_inline_ref *)ptr; type = btrfs_extent_inline_ref_type(leaf, iref); offset = btrfs_extent_inline_ref_offset(leaf, iref); switch (type) { case BTRFS_SHARED_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, 0, NULL, *info_level + 1, offset, bytenr, 1, GFP_NOFS); break; case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_shared_data_ref *sdref; int count; sdref = (struct btrfs_shared_data_ref *)(iref + 1); count = btrfs_shared_data_ref_count(leaf, sdref); ret = __add_prelim_ref(prefs, 0, NULL, 0, offset, bytenr, count, GFP_NOFS); break; } case BTRFS_TREE_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, offset, NULL, *info_level + 1, 0, bytenr, 1, GFP_NOFS); break; case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_extent_data_ref *dref; int count; u64 root; dref = (struct btrfs_extent_data_ref *)(&iref->offset); count = btrfs_extent_data_ref_count(leaf, dref); key.objectid = btrfs_extent_data_ref_objectid(leaf, dref); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = btrfs_extent_data_ref_offset(leaf, dref); root = btrfs_extent_data_ref_root(leaf, dref); ret = __add_prelim_ref(prefs, root, &key, 0, 0, bytenr, count, GFP_NOFS); break; } default: WARN_ON(1); } if (ret) return ret; ptr += btrfs_extent_inline_ref_size(type); } return 0; }
/* * add all non-inline backrefs for bytenr to the list */ static int __add_keyed_refs(struct btrfs_fs_info *fs_info, struct btrfs_path *path, u64 bytenr, int info_level, struct list_head *prefs) { struct btrfs_root *extent_root = fs_info->extent_root; int ret; int slot; struct extent_buffer *leaf; struct btrfs_key key; while (1) { ret = btrfs_next_item(extent_root, path); if (ret < 0) break; if (ret) { ret = 0; break; } slot = path->slots[0]; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid != bytenr) break; if (key.type < BTRFS_TREE_BLOCK_REF_KEY) continue; if (key.type > BTRFS_SHARED_DATA_REF_KEY) break; switch (key.type) { case BTRFS_SHARED_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, 0, NULL, info_level + 1, key.offset, bytenr, 1, GFP_NOFS); break; case BTRFS_SHARED_DATA_REF_KEY: { struct btrfs_shared_data_ref *sdref; int count; sdref = btrfs_item_ptr(leaf, slot, struct btrfs_shared_data_ref); count = btrfs_shared_data_ref_count(leaf, sdref); ret = __add_prelim_ref(prefs, 0, NULL, 0, key.offset, bytenr, count, GFP_NOFS); break; } case BTRFS_TREE_BLOCK_REF_KEY: ret = __add_prelim_ref(prefs, key.offset, NULL, info_level + 1, 0, bytenr, 1, GFP_NOFS); break; case BTRFS_EXTENT_DATA_REF_KEY: { struct btrfs_extent_data_ref *dref; int count; u64 root; dref = btrfs_item_ptr(leaf, slot, struct btrfs_extent_data_ref); count = btrfs_extent_data_ref_count(leaf, dref); key.objectid = btrfs_extent_data_ref_objectid(leaf, dref); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = btrfs_extent_data_ref_offset(leaf, dref); root = btrfs_extent_data_ref_root(leaf, dref); ret = __add_prelim_ref(prefs, root, &key, 0, 0, bytenr, count, GFP_NOFS); break; } default: WARN_ON(1); } if (ret) return ret; } return ret; }