diff options
Diffstat (limited to 'lib/radix-tree.c')
-rw-r--r-- | lib/radix-tree.c | 44 |
1 files changed, 18 insertions, 26 deletions
diff --git a/lib/radix-tree.c b/lib/radix-tree.c index ee56562..b1ca744 100644 --- a/lib/radix-tree.c +++ b/lib/radix-tree.c @@ -831,45 +831,37 @@ EXPORT_SYMBOL(radix_tree_tag_clear); int radix_tree_tag_get(struct radix_tree_root *root, unsigned long index, unsigned int tag) { - unsigned int height, shift; - struct radix_tree_node *node; + struct radix_tree_node *node, *parent; + unsigned long maxindex; + unsigned int shift; - /* check the root's tag bit */ if (!root_tag_get(root, tag)) return 0; - node = rcu_dereference_raw(root->rnode); + shift = radix_tree_load_root(root, &node, &maxindex); + if (index > maxindex) + return 0; if (node == NULL) return 0; - if (!radix_tree_is_indirect_ptr(node)) - return (index == 0); - node = indirect_to_ptr(node); - - height = node->path & RADIX_TREE_HEIGHT_MASK; - if (index > radix_tree_maxindex(height)) - return 0; + while (radix_tree_is_indirect_ptr(node)) { + int offset; - shift = (height - 1) * RADIX_TREE_MAP_SHIFT; + shift -= RADIX_TREE_MAP_SHIFT; + offset = (index >> shift) & RADIX_TREE_MAP_MASK; - for ( ; ; ) { - int offset; + parent = indirect_to_ptr(node); + offset = radix_tree_descend(parent, &node, offset); - if (node == NULL) + if (!node) return 0; - node = indirect_to_ptr(node); - - offset = (index >> shift) & RADIX_TREE_MAP_MASK; - if (!tag_get(node, tag, offset)) + if (!tag_get(parent, tag, offset)) return 0; - if (height == 1) - return 1; - node = rcu_dereference_raw(node->slots[offset]); - if (!radix_tree_is_indirect_ptr(node)) - return 1; - shift -= RADIX_TREE_MAP_SHIFT; - height--; + if (node == RADIX_TREE_RETRY) + break; } + + return 1; } EXPORT_SYMBOL(radix_tree_tag_get); |