/* SPDX-License-Identifier: GPL-2.0-only */ /* * Macros for manipulating and testing flags related to a * pageblock_nr_pages number of pages. * * Copyright (C) IBM Corporation, 2006 * * Original author, Mel Gorman * Major cleanups and reduction of bit operations, Andy Whitcroft */ #ifndef PAGEBLOCK_FLAGS_H #define PAGEBLOCK_FLAGS_H #include <linux/types.h> #define PB_migratetype_bits 3 /* Bit indices that affect a whole block of pages */ enum pageblock_bits { PB_migrate, PB_migrate_end = PB_migrate + PB_migratetype_bits - 1, /* 3 bits required for migrate types */ PB_migrate_skip,/* If set the block is skipped by compaction */ /* * Assume the bits will always align on a word. If this assumption * changes then get/set pageblock needs updating. */ NR_PAGEBLOCK_BITS }; #ifdef CONFIG_HUGETLB_PAGE #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE /* Huge page sizes are variable */ extern unsigned int pageblock_order; #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ /* Huge pages are a constant size */ #define pageblock_order HUGETLB_PAGE_ORDER #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ #else /* CONFIG_HUGETLB_PAGE */ /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */ #define pageblock_order (MAX_ORDER-1) #endif /* CONFIG_HUGETLB_PAGE */ #define pageblock_nr_pages (1UL << pageblock_order) /* Forward declaration */ struct page; unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn, unsigned long mask); void set_pfnblock_flags_mask(struct page *page, unsigned long flags, unsigned long pfn, unsigned long mask); /* Declarations for getting and setting flags. See mm/page_alloc.c */ #ifdef CONFIG_COMPACTION #define get_pageblock_skip(page) \ get_pfnblock_flags_mask(page, page_to_pfn(page), \ (1 << (PB_migrate_skip))) #define clear_pageblock_skip(page) \ set_pfnblock_flags_mask(page, 0, page_to_pfn(page), \ (1 << PB_migrate_skip)) #define set_pageblock_skip(page) \ set_pfnblock_flags_mask(page, (1 << PB_migrate_skip), \ page_to_pfn(page), \ (1 << PB_migrate_skip)) #else static inline bool get_pageblock_skip(struct page *page) { return false; } static inline void clear_pageblock_skip(struct page *page) { } static inline void set_pageblock_skip(struct page *page) { } #endif /* CONFIG_COMPACTION */ #endif /* PAGEBLOCK_FLAGS_H */