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 89 static inline bool get_pageblock_skip(struct page *page) 90 { 91 return false; 92 } 93 static inline void clear_pageblock_skip(struct page *page) 94 { 95 } 96 static inline void set_pageblock_skip(struct page *page) 97 { 98 } 99 #endif /* CONFIG_COMPACTION */ 100 101 #endif /* PAGEBLOCK_FLAGS_H */ 102