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 /*
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)
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
52
53 #endif /* CONFIG_HUGETLB_PAGE */
54
55 #define pageblock_nr_pages (1UL << pageblock_order)
56 #define pageblock_align(pfn) ALIGN((pfn), pageblock_nr_pages)
57 #define pageblock_aligned(pfn) IS_ALIGNED((pfn), pageblock_nr_pages)
58 #define pageblock_start_pfn(pfn) ALIGN_DOWN((pfn), pageblock_nr_pages)
59 #define pageblock_end_pfn(pfn) ALIGN((pfn) + 1, pageblock_nr_pages)
60
61 /* Forward declaration */
62 struct page;
63
64 unsigned long get_pfnblock_flags_mask(const struct page *page,
65 unsigned long pfn,
66 unsigned long mask);
67
68 void set_pfnblock_flags_mask(struct page *page,
69 unsigned long flags,
70 unsigned long pfn,
71 unsigned long mask);
72
73 /* Declarations for getting and setting flags. See mm/page_alloc.c */
74 #ifdef CONFIG_COMPACTION
75 #define get_pageblock_skip(page) \
76 get_pfnblock_flags_mask(page, page_to_pfn(page), \
77 (1 << (PB_migrate_skip)))
78 #define clear_pageblock_skip(page) \
79 set_pfnblock_flags_mask(page, 0, page_to_pfn(page), \
80 (1 << PB_migrate_skip))
81 #define set_pageblock_skip(page) \
82 set_pfnblock_flags_mask(page, (1 << PB_migrate_skip), \
83 page_to_pfn(page), \
84 (1 << PB_migrate_skip))
85 #else
get_pageblock_skip(struct page * page)86 static inline bool get_pageblock_skip(struct page *page)
87 {
88 return false;
89 }
clear_pageblock_skip(struct page * page)90 static inline void clear_pageblock_skip(struct page *page)
91 {
92 }
set_pageblock_skip(struct page * page)93 static inline void set_pageblock_skip(struct page *page)
94 {
95 }
96 #endif /* CONFIG_COMPACTION */
97
98 #endif /* PAGEBLOCK_FLAGS_H */
99