xref: /linux/include/linux/pageblock-flags.h (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
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 #if defined(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_PAGE_ORDER)
45 
46 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
47 
48 #elif defined(CONFIG_TRANSPARENT_HUGEPAGE)
49 
50 #define pageblock_order		MIN_T(unsigned int, HPAGE_PMD_ORDER, MAX_PAGE_ORDER)
51 
52 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
53 
54 /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
55 #define pageblock_order		MAX_PAGE_ORDER
56 
57 #endif /* CONFIG_HUGETLB_PAGE */
58 
59 #define pageblock_nr_pages	(1UL << pageblock_order)
60 #define pageblock_align(pfn)	ALIGN((pfn), pageblock_nr_pages)
61 #define pageblock_aligned(pfn)	IS_ALIGNED((pfn), pageblock_nr_pages)
62 #define pageblock_start_pfn(pfn)	ALIGN_DOWN((pfn), pageblock_nr_pages)
63 #define pageblock_end_pfn(pfn)		ALIGN((pfn) + 1, pageblock_nr_pages)
64 
65 /* Forward declaration */
66 struct page;
67 
68 unsigned long get_pfnblock_flags_mask(const struct page *page,
69 				unsigned long pfn,
70 				unsigned long mask);
71 
72 void set_pfnblock_flags_mask(struct page *page,
73 				unsigned long flags,
74 				unsigned long pfn,
75 				unsigned long mask);
76 
77 /* Declarations for getting and setting flags. See mm/page_alloc.c */
78 #ifdef CONFIG_COMPACTION
79 #define get_pageblock_skip(page) \
80 	get_pfnblock_flags_mask(page, page_to_pfn(page),	\
81 			(1 << (PB_migrate_skip)))
82 #define clear_pageblock_skip(page) \
83 	set_pfnblock_flags_mask(page, 0, page_to_pfn(page),	\
84 			(1 << PB_migrate_skip))
85 #define set_pageblock_skip(page) \
86 	set_pfnblock_flags_mask(page, (1 << PB_migrate_skip),	\
87 			page_to_pfn(page),			\
88 			(1 << PB_migrate_skip))
89 #else
get_pageblock_skip(struct page * page)90 static inline bool get_pageblock_skip(struct page *page)
91 {
92 	return false;
93 }
clear_pageblock_skip(struct page * page)94 static inline void clear_pageblock_skip(struct page *page)
95 {
96 }
set_pageblock_skip(struct page * page)97 static inline void set_pageblock_skip(struct page *page)
98 {
99 }
100 #endif /* CONFIG_COMPACTION */
101 
102 #endif	/* PAGEBLOCK_FLAGS_H */
103