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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/* Huge pages are a constant size */
41#define pageblock_order HUGETLB_PAGE_ORDER
42
43#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
44
45#else /* CONFIG_HUGETLB_PAGE */
46
47/* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
48#define pageblock_order (MAX_ORDER-1)
49
50#endif /* CONFIG_HUGETLB_PAGE */
51
52#define pageblock_nr_pages (1UL << pageblock_order)
53
54/* Forward declaration */
55struct page;
56
57unsigned long get_pfnblock_flags_mask(struct page *page,
58 unsigned long pfn,
59 unsigned long end_bitidx,
60 unsigned long mask);
61
62void set_pfnblock_flags_mask(struct page *page,
63 unsigned long flags,
64 unsigned long pfn,
65 unsigned long end_bitidx,
66 unsigned long mask);
67
68/* Declarations for getting and setting flags. See mm/page_alloc.c */
69#define get_pageblock_flags_group(page, start_bitidx, end_bitidx) \
70 get_pfnblock_flags_mask(page, page_to_pfn(page), \
71 end_bitidx, \
72 (1 << (end_bitidx - start_bitidx + 1)) - 1)
73#define set_pageblock_flags_group(page, flags, start_bitidx, end_bitidx) \
74 set_pfnblock_flags_mask(page, flags, page_to_pfn(page), \
75 end_bitidx, \
76 (1 << (end_bitidx - start_bitidx + 1)) - 1)
77
78#ifdef CONFIG_COMPACTION
79#define get_pageblock_skip(page) \
80 get_pageblock_flags_group(page, PB_migrate_skip, \
81 PB_migrate_skip)
82#define clear_pageblock_skip(page) \
83 set_pageblock_flags_group(page, 0, PB_migrate_skip, \
84 PB_migrate_skip)
85#define set_pageblock_skip(page) \
86 set_pageblock_flags_group(page, 1, PB_migrate_skip, \
87 PB_migrate_skip)
88#else
89static inline bool get_pageblock_skip(struct page *page)
90{
91 return false;
92}
93static inline void clear_pageblock_skip(struct page *page)
94{
95}
96static inline void set_pageblock_skip(struct page *page)
97{
98}
99#endif /* CONFIG_COMPACTION */
100
101#endif /* PAGEBLOCK_FLAGS_H */