static u64 compute_subtree_max_end(struct memtype *data)
{
u64 max_end = data->end, child_max_end;
child_max_end = get_subtree_max_end(data->rb.rb_right);
if (child_max_end > max_end)
max_end = child_max_end;
child_max_end = get_subtree_max_end(data->rb.rb_left);
if (child_max_end > max_end)
max_end = child_max_end;
return max_end;
}
/* Update 'subtree_max_end' for a node, based on node and its children */
static void memtype_rb_augment_cb(struct rb_node *node, void *__unused)
{
struct memtype *data;
u64 max_end, child_max_end;
if (!node)
return;
data = container_of(node, struct memtype, rb);
max_end = data->end;
child_max_end = get_subtree_max_end(node->rb_right);
if (child_max_end > max_end)
max_end = child_max_end;
child_max_end = get_subtree_max_end(node->rb_left);
if (child_max_end > max_end)
max_end = child_max_end;
data->subtree_max_end = max_end;
}
/* Update 'subtree_max_end' for a node, based on node and its children */
static void update_node_max_end(struct rb_node *node)
{
struct memtype *data;
u64 max_end, child_max_end;
if (!node)
return;
data = container_of(node, struct memtype, rb);
max_end = data->end;
child_max_end = get_subtree_max_end(node->rb_right);
if (child_max_end > max_end)
max_end = child_max_end;
child_max_end = get_subtree_max_end(node->rb_left);
if (child_max_end > max_end)
max_end = child_max_end;
data->subtree_max_end = max_end;
}
/* Find the first (lowest start addr) overlapping range from rb tree */
static struct memtype *memtype_rb_lowest_match(struct rb_root *root,
u64 start, u64 end)
{
struct rb_node *node = root->rb_node;
struct memtype *last_lower = NULL;
while (node) {
struct memtype *data = container_of(node, struct memtype, rb);
if (get_subtree_max_end(node->rb_left) > start) {
/* Lowest overlap if any must be on left side */
node = node->rb_left;
} else if (is_node_overlap(data, start, end)) {
last_lower = data;
break;
} else if (start >= data->start) {
/* Lowest overlap if any must be on right side */
node = node->rb_right;
} else {
break;
}
}
return last_lower; /* Returns NULL if there is no overlap */
}