diff options
-rw-r--r-- | include/linux/radix-tree.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 52b97db93830..af3581b8a451 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -461,6 +461,14 @@ static inline struct radix_tree_node *entry_to_node(void *ptr) * * This function updates @iter->index in the case of a successful lookup. * For tagged lookup it also eats @iter->tags. + * + * There are several cases where 'slot' can be passed in as NULL to this + * function. These cases result from the use of radix_tree_iter_next() or + * radix_tree_iter_retry(). In these cases we don't end up dereferencing + * 'slot' because either: + * a) we are doing tagged iteration and iter->tags has been set to 0, or + * b) we are doing non-tagged iteration, and iter->index and iter->next_index + * have been set up so that radix_tree_chunk_size() returns 1 or 0. */ static __always_inline void ** radix_tree_next_slot(void **slot, struct radix_tree_iter *iter, unsigned flags) |