diff options
| -rw-r--r-- | lib/radix-tree.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/lib/radix-tree.c b/lib/radix-tree.c index 799f341977d0..585965afc808 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -80,6 +80,46 @@ static inline void *indirect_to_ptr(void *ptr) return (void *)((unsigned long)ptr & ~RADIX_TREE_INDIRECT_PTR); } +#ifdef CONFIG_RADIX_TREE_MULTIORDER +/* Sibling slots point directly to another slot in the same node */ +static inline bool is_sibling_entry(struct radix_tree_node *parent, void *node) +{ + void **ptr = node; + return (parent->slots <= ptr) && + (ptr < parent->slots + RADIX_TREE_MAP_SIZE); +} +#else +static inline bool is_sibling_entry(struct radix_tree_node *parent, void *node) +{ + return false; +} +#endif + +static inline unsigned long get_slot_offset(struct radix_tree_node *parent, + void **slot) +{ + return slot - parent->slots; +} + +static unsigned radix_tree_descend(struct radix_tree_node *parent, + struct radix_tree_node **nodep, unsigned offset) +{ + void **entry = rcu_dereference_raw(parent->slots[offset]); + +#ifdef CONFIG_RADIX_TREE_MULTIORDER + if (radix_tree_is_indirect_ptr(entry)) { + unsigned long siboff = get_slot_offset(parent, entry); + if (siboff < RADIX_TREE_MAP_SIZE) { + offset = siboff; + entry = rcu_dereference_raw(parent->slots[offset]); + } + } +#endif + + *nodep = (void *)entry; + return offset; +} + static inline gfp_t root_gfp_mask(struct radix_tree_root *root) { return root->gfp_mask & __GFP_BITS_MASK; |