1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_PAGEWALK_H
3 #define _LINUX_PAGEWALK_H
4
5 #include <linux/mm.h>
6
7 struct mm_walk;
8
9 /**
10 * mm_walk_ops - callbacks for walk_page_range
11 * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry
12 * this handler should only handle pud_trans_huge() puds.
13 * the pmd_entry or pte_entry callbacks will be used for
14 * regular PUDs.
15 * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry
16 * this handler is required to be able to handle
17 * pmd_trans_huge() pmds. They may simply choose to
18 * split_huge_page() instead of handling it explicitly.
19 * @pte_entry: if set, called for each non-empty PTE (4th-level) entry
20 * @pte_hole: if set, called for each hole at all levels
21 * @hugetlb_entry: if set, called for each hugetlb entry
22 * @test_walk: caller specific callback function to determine whether
23 * we walk over the current vma or not. Returning 0 means
24 * "do page table walk over the current vma", returning
25 * a negative value means "abort current page table walk
26 * right now" and returning 1 means "skip the current vma"
27 */
28 struct mm_walk_ops {
29 int (*pud_entry)(pud_t *pud, unsigned long addr,
30 unsigned long next, struct mm_walk *walk);
31 int (*pmd_entry)(pmd_t *pmd, unsigned long addr,
32 unsigned long next, struct mm_walk *walk);
33 int (*pte_entry)(pte_t *pte, unsigned long addr,
34 unsigned long next, struct mm_walk *walk);
35 int (*pte_hole)(unsigned long addr, unsigned long next,
36 struct mm_walk *walk);
37 int (*hugetlb_entry)(pte_t *pte, unsigned long hmask,
38 unsigned long addr, unsigned long next,
39 struct mm_walk *walk);
40 int (*test_walk)(unsigned long addr, unsigned long next,
41 struct mm_walk *walk);
42 };
43
44 /**
45 * mm_walk - walk_page_range data
46 * @ops: operation to call during the walk
47 * @mm: mm_struct representing the target process of page table walk
48 * @vma: vma currently walked (NULL if walking outside vmas)
49 * @private: private data for callbacks' usage
50 *
51 * (see the comment on walk_page_range() for more details)
52 */
53 struct mm_walk {
54 const struct mm_walk_ops *ops;
55 struct mm_struct *mm;
56 struct vm_area_struct *vma;
57 void *private;
58 };
59
60 int walk_page_range(struct mm_struct *mm, unsigned long start,
61 unsigned long end, const struct mm_walk_ops *ops,
62 void *private);
63 int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops,
64 void *private);
65
66 #endif /* _LINUX_PAGEWALK_H */