include/linux/pageblock-flags.h

   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 #if defined(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_PAGE_ORDER)
  45
  46 #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */
  47
  48 #elif defined(CONFIG_TRANSPARENT_HUGEPAGE)
  49
  50 #define pageblock_order         MIN_T(unsigned int, HPAGE_PMD_ORDER, MAX_PAGE_ORDER)
  51
  52 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
  53
  54 /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
  55 #define pageblock_order         MAX_PAGE_ORDER
  56
  57 #endif /* CONFIG_HUGETLB_PAGE */
  58
  59 #define pageblock_nr_pages      (1UL << pageblock_order)
  60 #define pageblock_align(pfn)    ALIGN((pfn), pageblock_nr_pages)
  61 #define pageblock_aligned(pfn)  IS_ALIGNED((pfn), pageblock_nr_pages)
  62 #define pageblock_start_pfn(pfn)        ALIGN_DOWN((pfn), pageblock_nr_pages)
  63 #define pageblock_end_pfn(pfn)          ALIGN((pfn) + 1, pageblock_nr_pages)
  64
  65 /* Forward declaration */
  66 struct page;
  67
  68 unsigned long get_pfnblock_flags_mask(const struct page *page,
  69                                 unsigned long pfn,
  70                                 unsigned long mask);
  71
  72 void set_pfnblock_flags_mask(struct page *page,
  73                                 unsigned long flags,
  74                                 unsigned long pfn,
  75                                 unsigned long mask);
  76
  77 /* Declarations for getting and setting flags. See mm/page_alloc.c */
  78 #ifdef CONFIG_COMPACTION
  79 #define get_pageblock_skip(page) \
  80         get_pfnblock_flags_mask(page, page_to_pfn(page),        \
  81                         (1 << (PB_migrate_skip)))
  82 #define clear_pageblock_skip(page) \
  83         set_pfnblock_flags_mask(page, 0, page_to_pfn(page),     \
  84                         (1 << PB_migrate_skip))
  85 #define set_pageblock_skip(page) \
  86         set_pfnblock_flags_mask(page, (1 << PB_migrate_skip),   \
  87                         page_to_pfn(page),                      \
  88                         (1 << PB_migrate_skip))
  89 #else
  90 static inline bool get_pageblock_skip(struct page *page)
  91 {
  92         return false;
  93 }
  94 static inline void clear_pageblock_skip(struct page *page)
  95 {
  96 }
  97 static inline void set_pageblock_skip(struct page *page)
  98 {
  99 }
 100 #endif /* CONFIG_COMPACTION */
 101
 102 #endif  /* PAGEBLOCK_FLAGS_H */