diff options
Diffstat (limited to 'include/linux/radix-tree.h')
-rw-r--r-- | include/linux/radix-tree.h | 50 |
1 files changed, 45 insertions, 5 deletions
diff --git a/include/linux/radix-tree.h b/include/linux/radix-tree.h index 7c88ad156a29..51a97ac8bfbf 100644 --- a/include/linux/radix-tree.h +++ b/include/linux/radix-tree.h @@ -21,6 +21,7 @@ #ifndef _LINUX_RADIX_TREE_H #define _LINUX_RADIX_TREE_H +#include <linux/bitops.h> #include <linux/preempt.h> #include <linux/types.h> #include <linux/bug.h> @@ -270,8 +271,15 @@ static inline void radix_tree_replace_slot(void **pslot, void *item) } int __radix_tree_create(struct radix_tree_root *root, unsigned long index, - struct radix_tree_node **nodep, void ***slotp); -int radix_tree_insert(struct radix_tree_root *, unsigned long, void *); + unsigned order, struct radix_tree_node **nodep, + void ***slotp); +int __radix_tree_insert(struct radix_tree_root *, unsigned long index, + unsigned order, void *); +static inline int radix_tree_insert(struct radix_tree_root *root, + unsigned long index, void *entry) +{ + return __radix_tree_insert(root, index, 0, entry); +} void *__radix_tree_lookup(struct radix_tree_root *root, unsigned long index, struct radix_tree_node **nodep, void ***slotp); void *radix_tree_lookup(struct radix_tree_root *, unsigned long); @@ -379,12 +387,44 @@ void **radix_tree_next_chunk(struct radix_tree_root *root, struct radix_tree_iter *iter, unsigned flags); /** + * radix_tree_iter_retry - retry this chunk of the iteration + * @iter: iterator state + * + * If we iterate over a tree protected only by the RCU lock, a race + * against deletion or creation may result in seeing a slot for which + * radix_tree_deref_retry() returns true. If so, call this function + * and continue the iteration. + */ +static inline __must_check +void **radix_tree_iter_retry(struct radix_tree_iter *iter) +{ + iter->next_index = iter->index; + return NULL; +} + +/** + * radix_tree_iter_next - resume iterating when the chunk may be invalid + * @iter: iterator state + * + * If the iterator needs to release then reacquire a lock, the chunk may + * have been invalidated by an insertion or deletion. Call this function + * to continue the iteration from the next index. + */ +static inline __must_check +void **radix_tree_iter_next(struct radix_tree_iter *iter) +{ + iter->next_index = iter->index + 1; + iter->tags = 0; + return NULL; +} + +/** * radix_tree_chunk_size - get current chunk size * * @iter: pointer to radix tree iterator * Returns: current chunk size */ -static __always_inline unsigned +static __always_inline long radix_tree_chunk_size(struct radix_tree_iter *iter) { return iter->next_index - iter->index; @@ -418,9 +458,9 @@ radix_tree_next_slot(void **slot, struct radix_tree_iter *iter, unsigned flags) return slot + offset + 1; } } else { - unsigned size = radix_tree_chunk_size(iter) - 1; + long size = radix_tree_chunk_size(iter); - while (size--) { + while (--size > 0) { slot++; iter->index++; if (likely(*slot)) |