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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Macros for manipulating and testing flags related to a
4 * pageblock_nr_pages number of pages.
5 *
6 * Copyright (C) IBM Corporation, 2006
7 *
8 * Original author, Mel Gorman
9 * Major cleanups and reduction of bit operations, Andy Whitcroft
10 */
11#ifndef PAGEBLOCK_FLAGS_H
12#define PAGEBLOCK_FLAGS_H
13
14#include <linux/types.h>
15
16#define PB_migratetype_bits 3
17/* Bit indices that affect a whole block of pages */
18enum pageblock_bits {
19 PB_migrate,
20 PB_migrate_end = PB_migrate + PB_migratetype_bits - 1,
21 /* 3 bits required for migrate types */
22 PB_migrate_skip,/* If set the block is skipped by compaction */
23
24 /*
25 * Assume the bits will always align on a word. If this assumption
26 * changes then get/set pageblock needs updating.
27 */
28 NR_PAGEBLOCK_BITS
29};
30
31#ifdef CONFIG_HUGETLB_PAGE
32
33#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
34
35/* Huge page sizes are variable */
36extern unsigned int pageblock_order;
37
38#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
39
40/*
41 * Huge pages are a constant size, but don't exceed the maximum allocation
42 * granularity.
43 */
44#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER - 1)
45
46#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
47
48#else /* CONFIG_HUGETLB_PAGE */
49
50/* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
51#define pageblock_order (MAX_ORDER-1)
52
53#endif /* CONFIG_HUGETLB_PAGE */
54
55#define pageblock_nr_pages (1UL << pageblock_order)
56
57/* Forward declaration */
58struct page;
59
60unsigned long get_pfnblock_flags_mask(const struct page *page,
61 unsigned long pfn,
62 unsigned long mask);
63
64void set_pfnblock_flags_mask(struct page *page,
65 unsigned long flags,
66 unsigned long pfn,
67 unsigned long mask);
68
69/* Declarations for getting and setting flags. See mm/page_alloc.c */
70#ifdef CONFIG_COMPACTION
71#define get_pageblock_skip(page) \
72 get_pfnblock_flags_mask(page, page_to_pfn(page), \
73 (1 << (PB_migrate_skip)))
74#define clear_pageblock_skip(page) \
75 set_pfnblock_flags_mask(page, 0, page_to_pfn(page), \
76 (1 << PB_migrate_skip))
77#define set_pageblock_skip(page) \
78 set_pfnblock_flags_mask(page, (1 << PB_migrate_skip), \
79 page_to_pfn(page), \
80 (1 << PB_migrate_skip))
81#else
82static inline bool get_pageblock_skip(struct page *page)
83{
84 return false;
85}
86static inline void clear_pageblock_skip(struct page *page)
87{
88}
89static inline void set_pageblock_skip(struct page *page)
90{
91}
92#endif /* CONFIG_COMPACTION */
93
94#endif /* PAGEBLOCK_FLAGS_H */