1 // SPDX-License-Identifier: GPL-2.0-only
3 * mm/interval_tree.c - interval tree for mapping->i_mmap
5 * Copyright (C) 2012, Michel Lespinasse <walken@google.com>
10 #include <linux/rmap.h>
11 #include <linux/interval_tree_generic.h>
13 static inline unsigned long vma_start_pgoff(struct vm_area_struct *v)
18 static inline unsigned long vma_last_pgoff(struct vm_area_struct *v)
20 return v->vm_pgoff + vma_pages(v) - 1;
23 INTERVAL_TREE_DEFINE(struct vm_area_struct, shared.rb,
24 unsigned long, shared.rb_subtree_last,
25 vma_start_pgoff, vma_last_pgoff, /* empty */, vma_interval_tree)
27 /* Insert node immediately after prev in the interval tree */
28 void vma_interval_tree_insert_after(struct vm_area_struct *node,
29 struct vm_area_struct *prev,
30 struct rb_root_cached *root)
32 struct rb_node **link;
33 struct vm_area_struct *parent;
34 unsigned long last = vma_last_pgoff(node);
36 VM_BUG_ON_VMA(vma_start_pgoff(node) != vma_start_pgoff(prev), node);
38 if (!prev->shared.rb.rb_right) {
40 link = &prev->shared.rb.rb_right;
42 parent = rb_entry(prev->shared.rb.rb_right,
43 struct vm_area_struct, shared.rb);
44 if (parent->shared.rb_subtree_last < last)
45 parent->shared.rb_subtree_last = last;
46 while (parent->shared.rb.rb_left) {
47 parent = rb_entry(parent->shared.rb.rb_left,
48 struct vm_area_struct, shared.rb);
49 if (parent->shared.rb_subtree_last < last)
50 parent->shared.rb_subtree_last = last;
52 link = &parent->shared.rb.rb_left;
55 node->shared.rb_subtree_last = last;
56 rb_link_node(&node->shared.rb, &parent->shared.rb, link);
57 rb_insert_augmented(&node->shared.rb, &root->rb_root,
58 &vma_interval_tree_augment);
61 static inline unsigned long avc_start_pgoff(struct anon_vma_chain *avc)
63 return vma_start_pgoff(avc->vma);
66 static inline unsigned long avc_last_pgoff(struct anon_vma_chain *avc)
68 return vma_last_pgoff(avc->vma);
71 INTERVAL_TREE_DEFINE(struct anon_vma_chain, rb, unsigned long, rb_subtree_last,
72 avc_start_pgoff, avc_last_pgoff,
73 static inline, __anon_vma_interval_tree)
75 void anon_vma_interval_tree_insert(struct anon_vma_chain *node,
76 struct rb_root_cached *root)
78 #ifdef CONFIG_DEBUG_VM_RB
79 node->cached_vma_start = avc_start_pgoff(node);
80 node->cached_vma_last = avc_last_pgoff(node);
82 __anon_vma_interval_tree_insert(node, root);
85 void anon_vma_interval_tree_remove(struct anon_vma_chain *node,
86 struct rb_root_cached *root)
88 __anon_vma_interval_tree_remove(node, root);
91 struct anon_vma_chain *
92 anon_vma_interval_tree_iter_first(struct rb_root_cached *root,
93 unsigned long first, unsigned long last)
95 return __anon_vma_interval_tree_iter_first(root, first, last);
98 struct anon_vma_chain *
99 anon_vma_interval_tree_iter_next(struct anon_vma_chain *node,
100 unsigned long first, unsigned long last)
102 return __anon_vma_interval_tree_iter_next(node, first, last);
105 #ifdef CONFIG_DEBUG_VM_RB
106 void anon_vma_interval_tree_verify(struct anon_vma_chain *node)
108 WARN_ON_ONCE(node->cached_vma_start != avc_start_pgoff(node));
109 WARN_ON_ONCE(node->cached_vma_last != avc_last_pgoff(node));