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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * mm/interval_tree.c - interval tree for mapping->i_mmap4 *5 * Copyright (C) 2012, Michel Lespinasse <walken@google.com>6 */7 8#include <linux/mm.h>9#include <linux/fs.h>10#include <linux/rmap.h>11#include <linux/interval_tree_generic.h>12 13static inline unsigned long vma_start_pgoff(struct vm_area_struct *v)14{15 return v->vm_pgoff;16}17 18static inline unsigned long vma_last_pgoff(struct vm_area_struct *v)19{20 return v->vm_pgoff + vma_pages(v) - 1;21}22 23INTERVAL_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)26 27/* Insert node immediately after prev in the interval tree */28void vma_interval_tree_insert_after(struct vm_area_struct *node,29 struct vm_area_struct *prev,30 struct rb_root_cached *root)31{32 struct rb_node **link;33 struct vm_area_struct *parent;34 unsigned long last = vma_last_pgoff(node);35 36 VM_BUG_ON_VMA(vma_start_pgoff(node) != vma_start_pgoff(prev), node);37 38 if (!prev->shared.rb.rb_right) {39 parent = prev;40 link = &prev->shared.rb.rb_right;41 } else {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;51 }52 link = &parent->shared.rb.rb_left;53 }54 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);59}60 61static inline unsigned long avc_start_pgoff(struct anon_vma_chain *avc)62{63 return vma_start_pgoff(avc->vma);64}65 66static inline unsigned long avc_last_pgoff(struct anon_vma_chain *avc)67{68 return vma_last_pgoff(avc->vma);69}70 71INTERVAL_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)74 75void anon_vma_interval_tree_insert(struct anon_vma_chain *node,76 struct rb_root_cached *root)77{78#ifdef CONFIG_DEBUG_VM_RB79 node->cached_vma_start = avc_start_pgoff(node);80 node->cached_vma_last = avc_last_pgoff(node);81#endif82 __anon_vma_interval_tree_insert(node, root);83}84 85void anon_vma_interval_tree_remove(struct anon_vma_chain *node,86 struct rb_root_cached *root)87{88 __anon_vma_interval_tree_remove(node, root);89}90 91struct anon_vma_chain *92anon_vma_interval_tree_iter_first(struct rb_root_cached *root,93 unsigned long first, unsigned long last)94{95 return __anon_vma_interval_tree_iter_first(root, first, last);96}97 98struct anon_vma_chain *99anon_vma_interval_tree_iter_next(struct anon_vma_chain *node,100 unsigned long first, unsigned long last)101{102 return __anon_vma_interval_tree_iter_next(node, first, last);103}104 105#ifdef CONFIG_DEBUG_VM_RB106void anon_vma_interval_tree_verify(struct anon_vma_chain *node)107{108 WARN_ON_ONCE(node->cached_vma_start != avc_start_pgoff(node));109 WARN_ON_ONCE(node->cached_vma_last != avc_last_pgoff(node));110}111#endif112