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 */
18 enum 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 */
36 extern 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 */
55 struct page;
56
57 unsigned long get_pfnblock_flags_mask(struct page *page,
58 unsigned long pfn,
59 unsigned long end_bitidx,
60 unsigned long mask);
61
62 void 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
get_pageblock_skip(struct page * page)89 static inline bool get_pageblock_skip(struct page *page)
90 {
91 return false;
92 }
clear_pageblock_skip(struct page * page)93 static inline void clear_pageblock_skip(struct page *page)
94 {
95 }
set_pageblock_skip(struct page * page)96 static inline void set_pageblock_skip(struct page *page)
97 {
98 }
99 #endif /* CONFIG_COMPACTION */
100
101 #endif /* PAGEBLOCK_FLAGS_H */
102