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 mask); 60 61 void set_pfnblock_flags_mask(struct page *page, 62 unsigned long flags, 63 unsigned long pfn, 64 unsigned long mask); 65 66 /* Declarations for getting and setting flags. See mm/page_alloc.c */ 67 #ifdef CONFIG_COMPACTION 68 #define get_pageblock_skip(page) \ 69 get_pfnblock_flags_mask(page, page_to_pfn(page), \ 70 (1 << (PB_migrate_skip))) 71 #define clear_pageblock_skip(page) \ 72 set_pfnblock_flags_mask(page, 0, page_to_pfn(page), \ 73 (1 << PB_migrate_skip)) 74 #define set_pageblock_skip(page) \ 75 set_pfnblock_flags_mask(page, (1 << PB_migrate_skip), \ 76 page_to_pfn(page), \ 77 (1 << PB_migrate_skip)) 78 #else get_pageblock_skip(struct page * page)79 static inline bool get_pageblock_skip(struct page *page) 80 { 81 return false; 82 } clear_pageblock_skip(struct page * page)83 static inline void clear_pageblock_skip(struct page *page) 84 { 85 } set_pageblock_skip(struct page * page)86 static inline void set_pageblock_skip(struct page *page) 87 { 88 } 89 #endif /* CONFIG_COMPACTION */ 90 91 #endif /* PAGEBLOCK_FLAGS_H */ 92