Commit 08f088dd authored by Filipe Manana's avatar Filipe Manana Committed by David Sterba
Browse files

btrfs: remove unnecessary NULL pointer checks when searching extent maps 



The previous and next pointer arguments passed to __tree_search() are
never NULL as the only caller of this function, __lookup_extent_mapping(),
always passes the address of two on stack pointers. So remove the NULL
checks and add assertions to verify the pointers.

Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 74333c7d

fs/btrfs/extent_map.c

+14 −14
Original line number Diff line number Diff line
@@ -150,6 +150,9 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 offset, 
	struct extent_map *entry;

	struct extent_map *prev_entry = NULL;



	ASSERT(prev_ret);

	ASSERT(next_ret);



	while (n) {

		entry = rb_entry(n, struct extent_map, rb_node);

		prev = n;
@@ -163,7 +166,6 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 offset, 
			return n;

	}



	if (prev_ret) {

	orig_prev = prev;

	while (prev && offset >= extent_map_end(prev_entry)) {

		prev = rb_next(prev);
@@ -171,16 +173,14 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 offset, 
	}

	*prev_ret = prev;

	prev = orig_prev;

	}



	if (next_ret) {

	prev_entry = rb_entry(prev, struct extent_map, rb_node);

	while (prev && offset < prev_entry->start) {

		prev = rb_prev(prev);

		prev_entry = rb_entry(prev, struct extent_map, rb_node);

	}

	*next_ret = prev;

	}



	return NULL;

}