diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 4837dcf06ba4..daac20c1a417 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -2514,3 +2514,48 @@ struct btrfs_backref_edge *btrfs_backref_alloc_edge( cache->nr_edges++; return edge; } + +/* + * Drop the backref node from cache, also cleaning up all its + * upper edges and any uncached nodes in the path. + * + * This cleanup happens bottom up, thus the node should either + * be the lowest node in the cache or a detached node. + */ +void btrfs_backref_cleanup_node(struct btrfs_backref_cache *cache, + struct btrfs_backref_node *node) +{ + struct btrfs_backref_node *upper; + struct btrfs_backref_edge *edge; + + if (!node) + return; + + BUG_ON(!node->lowest && !node->detached); + while (!list_empty(&node->upper)) { + edge = list_entry(node->upper.next, struct btrfs_backref_edge, + list[LOWER]); + upper = edge->node[UPPER]; + list_del(&edge->list[LOWER]); + list_del(&edge->list[UPPER]); + btrfs_backref_free_edge(cache, edge); + + if (RB_EMPTY_NODE(&upper->rb_node)) { + BUG_ON(!list_empty(&node->upper)); + btrfs_backref_drop_node(cache, node); + node = upper; + node->lowest = 1; + continue; + } + /* + * Add the node to leaf node list if no other child block + * cached. + */ + if (list_empty(&upper->lower)) { + list_add_tail(&upper->lower, &cache->leaves); + upper->lowest = 1; + } + } + + btrfs_backref_drop_node(cache, node); +} diff --git a/fs/btrfs/backref.h b/fs/btrfs/backref.h index a14c79bbbeb9..1710cf994f4c 100644 --- a/fs/btrfs/backref.h +++ b/fs/btrfs/backref.h @@ -350,4 +350,7 @@ static inline void btrfs_backref_drop_node(struct btrfs_backref_cache *tree, btrfs_backref_free_node(tree, node); } +void btrfs_backref_cleanup_node(struct btrfs_backref_cache *cache, + struct btrfs_backref_node *node); + #endif diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index d23b9a54e002..4b7d7d54c64b 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -153,9 +153,6 @@ struct reloc_control { #define MOVE_DATA_EXTENTS 0 #define UPDATE_DATA_PTRS 1 -static void remove_backref_node(struct btrfs_backref_cache *cache, - struct btrfs_backref_node *node); - static void mark_block_processed(struct reloc_control *rc, struct btrfs_backref_node *node) { @@ -186,13 +183,13 @@ static void backref_cache_cleanup(struct btrfs_backref_cache *cache) while (!list_empty(&cache->detached)) { node = list_entry(cache->detached.next, struct btrfs_backref_node, list); - remove_backref_node(cache, node); + btrfs_backref_cleanup_node(cache, node); } while (!list_empty(&cache->leaves)) { node = list_entry(cache->leaves.next, struct btrfs_backref_node, lower); - remove_backref_node(cache, node); + btrfs_backref_cleanup_node(cache, node); } cache->last_trans = 0; @@ -268,46 +265,6 @@ static struct btrfs_backref_node *walk_down_backref( *index = 0; return NULL; } -/* - * remove a backref node from the backref cache - */ -static void remove_backref_node(struct btrfs_backref_cache *cache, - struct btrfs_backref_node *node) -{ - struct btrfs_backref_node *upper; - struct btrfs_backref_edge *edge; - - if (!node) - return; - - BUG_ON(!node->lowest && !node->detached); - while (!list_empty(&node->upper)) { - edge = list_entry(node->upper.next, struct btrfs_backref_edge, - list[LOWER]); - upper = edge->node[UPPER]; - list_del(&edge->list[LOWER]); - list_del(&edge->list[UPPER]); - btrfs_backref_free_edge(cache, edge); - - if (RB_EMPTY_NODE(&upper->rb_node)) { - BUG_ON(!list_empty(&node->upper)); - btrfs_backref_drop_node(cache, node); - node = upper; - node->lowest = 1; - continue; - } - /* - * add the node to leaf node list if no other - * child block cached. - */ - if (list_empty(&upper->lower)) { - list_add_tail(&upper->lower, &cache->leaves); - upper->lowest = 1; - } - } - - btrfs_backref_drop_node(cache, node); -} static void update_backref_node(struct btrfs_backref_cache *cache, struct btrfs_backref_node *node, u64 bytenr) @@ -345,7 +302,7 @@ static int update_backref_cache(struct btrfs_trans_handle *trans, while (!list_empty(&cache->detached)) { node = list_entry(cache->detached.next, struct btrfs_backref_node, list); - remove_backref_node(cache, node); + btrfs_backref_cleanup_node(cache, node); } while (!list_empty(&cache->changed)) { @@ -1120,7 +1077,7 @@ static noinline_for_stack struct btrfs_backref_node *build_backref_tree( btrfs_backref_free_node(cache, lower); } - remove_backref_node(cache, node); + btrfs_backref_cleanup_node(cache, node); ASSERT(list_empty(&cache->useless_node) && list_empty(&cache->pending_edge)); return ERR_PTR(err); @@ -3103,7 +3060,7 @@ static int relocate_tree_block(struct btrfs_trans_handle *trans, } out: if (ret || node->level == 0 || node->cowonly) - remove_backref_node(&rc->backref_cache, node); + btrfs_backref_cleanup_node(&rc->backref_cache, node); return ret; }