1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Macros for manipulating and testing flags related to a
4 * pageblock_nr_pages number of pages.
6 * Copyright (C) IBM Corporation, 2006
8 * Original author, Mel Gorman
9 * Major cleanups and reduction of bit operations, Andy Whitcroft
11 #ifndef PAGEBLOCK_FLAGS_H
12 #define PAGEBLOCK_FLAGS_H
14 #include <linux/types.h>
16 #define PB_migratetype_bits 3
17 /* Bit indices that affect a whole block of pages */
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 */
25 * Assume the bits will always align on a word. If this assumption
26 * changes then get/set pageblock needs updating.
31 #ifdef CONFIG_HUGETLB_PAGE
33 #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
35 /* Huge page sizes are variable */
36 extern unsigned int pageblock_order;
38 #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
40 /* Huge pages are a constant size */
41 #define pageblock_order HUGETLB_PAGE_ORDER
43 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
45 #else /* CONFIG_HUGETLB_PAGE */
47 /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
48 #define pageblock_order (MAX_ORDER-1)
50 #endif /* CONFIG_HUGETLB_PAGE */
52 #define pageblock_nr_pages (1UL << pageblock_order)
54 /* Forward declaration */
57 unsigned long get_pfnblock_flags_mask(struct page *page,
59 unsigned long end_bitidx,
62 void set_pfnblock_flags_mask(struct page *page,
65 unsigned long end_bitidx,
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), \
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), \
76 (1 << (end_bitidx - start_bitidx + 1)) - 1)
78 #ifdef CONFIG_COMPACTION
79 #define get_pageblock_skip(page) \
80 get_pageblock_flags_group(page, PB_migrate_skip, \
82 #define clear_pageblock_skip(page) \
83 set_pageblock_flags_group(page, 0, PB_migrate_skip, \
85 #define set_pageblock_skip(page) \
86 set_pageblock_flags_group(page, 1, PB_migrate_skip, \
89 static inline bool get_pageblock_skip(struct page *page)
93 static inline void clear_pageblock_skip(struct page *page)
96 static inline void set_pageblock_skip(struct page *page)
99 #endif /* CONFIG_COMPACTION */
101 #endif /* PAGEBLOCK_FLAGS_H */