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