diff options
| -rw-r--r-- | fs/btrfs/extent_map.c | 85 |
1 files changed, 29 insertions, 56 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 911a9db..df7a803 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -299,19 +299,8 @@ static u64 range_end(u64 start, u64 len) return start + len; } -/** - * lookup_extent_mapping - lookup extent_map - * @tree: tree to lookup in - * @start: byte offset to start the search - * @len: length of the lookup range - * - * Find and return the first extent_map struct in @tree that intersects the - * [start, len] range. There may be additional objects in the tree that - * intersect, so check the object returned carefully to make sure that no - * additional lookups are needed. - */ -struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, - u64 start, u64 len) +struct extent_map *__lookup_extent_mapping(struct extent_map_tree *tree, + u64 start, u64 len, int strict) { struct extent_map *em; struct rb_node *rb_node; @@ -320,38 +309,42 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, u64 end = range_end(start, len); rb_node = __tree_search(&tree->map, start, &prev, &next); - if (!rb_node && prev) { - em = rb_entry(prev, struct extent_map, rb_node); - if (end > em->start && start < extent_map_end(em)) - goto found; - } - if (!rb_node && next) { - em = rb_entry(next, struct extent_map, rb_node); - if (end > em->start && start < extent_map_end(em)) - goto found; - } if (!rb_node) { - em = NULL; - goto out; - } - if (IS_ERR(rb_node)) { - em = ERR_CAST(rb_node); - goto out; + if (prev) + rb_node = prev; + else if (next) + rb_node = next; + else + return NULL; } + em = rb_entry(rb_node, struct extent_map, rb_node); - if (end > em->start && start < extent_map_end(em)) - goto found; - em = NULL; - goto out; + if (strict && !(end > em->start && start < extent_map_end(em))) + return NULL; -found: atomic_inc(&em->refs); -out: return em; } /** + * lookup_extent_mapping - lookup extent_map + * @tree: tree to lookup in + * @start: byte offset to start the search + * @len: length of the lookup range + * + * Find and return the first extent_map struct in @tree that intersects the + * [start, len] range. There may be additional objects in the tree that + * intersect, so check the object returned carefully to make sure that no + * additional lookups are needed. + */ +struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, + u64 start, u64 len) +{ + return __lookup_extent_mapping(tree, start, len, 1); +} + +/** * search_extent_mapping - find a nearby extent map * @tree: tree to lookup in * @start: byte offset to start the search @@ -365,27 +358,7 @@ out: struct extent_map *search_extent_mapping(struct extent_map_tree *tree, u64 start, u64 len) { - struct extent_map *em; - struct rb_node *rb_node; - struct rb_node *prev = NULL; - struct rb_node *next = NULL; - - rb_node = __tree_search(&tree->map, start, &prev, &next); - if (!rb_node && prev) { - em = rb_entry(prev, struct extent_map, rb_node); - goto found; - } - if (!rb_node && next) { - em = rb_entry(next, struct extent_map, rb_node); - goto found; - } - if (!rb_node) - return NULL; - - em = rb_entry(rb_node, struct extent_map, rb_node); -found: - atomic_inc(&em->refs); - return em; + return __lookup_extent_mapping(tree, start, len, 0); } /** |
