xref: /OK3568_Linux_fs/kernel/include/linux/pageblock-flags.h (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Macros for manipulating and testing flags related to a
4*4882a593Smuzhiyun  * pageblock_nr_pages number of pages.
5*4882a593Smuzhiyun  *
6*4882a593Smuzhiyun  * Copyright (C) IBM Corporation, 2006
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  * Original author, Mel Gorman
9*4882a593Smuzhiyun  * Major cleanups and reduction of bit operations, Andy Whitcroft
10*4882a593Smuzhiyun  */
11*4882a593Smuzhiyun #ifndef PAGEBLOCK_FLAGS_H
12*4882a593Smuzhiyun #define PAGEBLOCK_FLAGS_H
13*4882a593Smuzhiyun 
14*4882a593Smuzhiyun #include <linux/types.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun #define PB_migratetype_bits 3
17*4882a593Smuzhiyun /* Bit indices that affect a whole block of pages */
18*4882a593Smuzhiyun enum pageblock_bits {
19*4882a593Smuzhiyun 	PB_migrate,
20*4882a593Smuzhiyun 	PB_migrate_end = PB_migrate + PB_migratetype_bits - 1,
21*4882a593Smuzhiyun 			/* 3 bits required for migrate types */
22*4882a593Smuzhiyun 	PB_migrate_skip,/* If set the block is skipped by compaction */
23*4882a593Smuzhiyun 
24*4882a593Smuzhiyun 	/*
25*4882a593Smuzhiyun 	 * Assume the bits will always align on a word. If this assumption
26*4882a593Smuzhiyun 	 * changes then get/set pageblock needs updating.
27*4882a593Smuzhiyun 	 */
28*4882a593Smuzhiyun 	NR_PAGEBLOCK_BITS
29*4882a593Smuzhiyun };
30*4882a593Smuzhiyun 
31*4882a593Smuzhiyun #ifdef CONFIG_HUGETLB_PAGE
32*4882a593Smuzhiyun 
33*4882a593Smuzhiyun #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
34*4882a593Smuzhiyun 
35*4882a593Smuzhiyun /* Huge page sizes are variable */
36*4882a593Smuzhiyun extern unsigned int pageblock_order;
37*4882a593Smuzhiyun 
38*4882a593Smuzhiyun #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
39*4882a593Smuzhiyun 
40*4882a593Smuzhiyun /* Huge pages are a constant size */
41*4882a593Smuzhiyun #define pageblock_order		HUGETLB_PAGE_ORDER
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
44*4882a593Smuzhiyun 
45*4882a593Smuzhiyun #else /* CONFIG_HUGETLB_PAGE */
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
48*4882a593Smuzhiyun #define pageblock_order		(MAX_ORDER-1)
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun #endif /* CONFIG_HUGETLB_PAGE */
51*4882a593Smuzhiyun 
52*4882a593Smuzhiyun #define pageblock_nr_pages	(1UL << pageblock_order)
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun /* Forward declaration */
55*4882a593Smuzhiyun struct page;
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun unsigned long get_pfnblock_flags_mask(struct page *page,
58*4882a593Smuzhiyun 				unsigned long pfn,
59*4882a593Smuzhiyun 				unsigned long mask);
60*4882a593Smuzhiyun 
61*4882a593Smuzhiyun void set_pfnblock_flags_mask(struct page *page,
62*4882a593Smuzhiyun 				unsigned long flags,
63*4882a593Smuzhiyun 				unsigned long pfn,
64*4882a593Smuzhiyun 				unsigned long mask);
65*4882a593Smuzhiyun 
66*4882a593Smuzhiyun /* Declarations for getting and setting flags. See mm/page_alloc.c */
67*4882a593Smuzhiyun #ifdef CONFIG_COMPACTION
68*4882a593Smuzhiyun #define get_pageblock_skip(page) \
69*4882a593Smuzhiyun 	get_pfnblock_flags_mask(page, page_to_pfn(page),	\
70*4882a593Smuzhiyun 			(1 << (PB_migrate_skip)))
71*4882a593Smuzhiyun #define clear_pageblock_skip(page) \
72*4882a593Smuzhiyun 	set_pfnblock_flags_mask(page, 0, page_to_pfn(page),	\
73*4882a593Smuzhiyun 			(1 << PB_migrate_skip))
74*4882a593Smuzhiyun #define set_pageblock_skip(page) \
75*4882a593Smuzhiyun 	set_pfnblock_flags_mask(page, (1 << PB_migrate_skip),	\
76*4882a593Smuzhiyun 			page_to_pfn(page),			\
77*4882a593Smuzhiyun 			(1 << PB_migrate_skip))
78*4882a593Smuzhiyun #else
get_pageblock_skip(struct page * page)79*4882a593Smuzhiyun static inline bool get_pageblock_skip(struct page *page)
80*4882a593Smuzhiyun {
81*4882a593Smuzhiyun 	return false;
82*4882a593Smuzhiyun }
clear_pageblock_skip(struct page * page)83*4882a593Smuzhiyun static inline void clear_pageblock_skip(struct page *page)
84*4882a593Smuzhiyun {
85*4882a593Smuzhiyun }
set_pageblock_skip(struct page * page)86*4882a593Smuzhiyun static inline void set_pageblock_skip(struct page *page)
87*4882a593Smuzhiyun {
88*4882a593Smuzhiyun }
89*4882a593Smuzhiyun #endif /* CONFIG_COMPACTION */
90*4882a593Smuzhiyun 
91*4882a593Smuzhiyun #endif	/* PAGEBLOCK_FLAGS_H */
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