include/linux/bootmem_info.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LINUX_BOOTMEM_INFO_H
   3 #define __LINUX_BOOTMEM_INFO_H
   4
   5 #include <linux/mm.h>
   6 #include <linux/kmemleak.h>
   7
   8 /*
   9  * Types for free bootmem stored in the low bits of page->private.
  10  */
  11 enum bootmem_type {
  12         MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE = 1,
  13         SECTION_INFO = MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE,
  14         MIX_SECTION_INFO,
  15         NODE_INFO,
  16         MEMORY_HOTPLUG_MAX_BOOTMEM_TYPE = NODE_INFO,
  17 };
  18
  19 #ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
  20 void __init register_page_bootmem_info_node(struct pglist_data *pgdat);
  21
  22 void get_page_bootmem(unsigned long info, struct page *page,
  23                 enum bootmem_type type);
  24 void put_page_bootmem(struct page *page);
  25
  26 static inline enum bootmem_type bootmem_type(const struct page *page)
  27 {
  28         return (unsigned long)page->private & 0xf;
  29 }
  30
  31 static inline unsigned long bootmem_info(const struct page *page)
  32 {
  33         return (unsigned long)page->private >> 4;
  34 }
  35
  36 /*
  37  * Any memory allocated via the memblock allocator and not via the
  38  * buddy will be marked reserved already in the memmap. For those
  39  * pages, we can call this function to free it to buddy allocator.
  40  */
  41 static inline void free_bootmem_page(struct page *page)
  42 {
  43         enum bootmem_type type = bootmem_type(page);
  44
  45         /*
  46          * The reserve_bootmem_region sets the reserved flag on bootmem
  47          * pages.
  48          */
  49         VM_BUG_ON_PAGE(page_ref_count(page) != 2, page);
  50
  51         if (type == SECTION_INFO || type == MIX_SECTION_INFO)
  52                 put_page_bootmem(page);
  53         else
  54                 VM_BUG_ON_PAGE(1, page);
  55 }
  56 #else
  57 static inline void register_page_bootmem_info_node(struct pglist_data *pgdat)
  58 {
  59 }
  60
  61 static inline void put_page_bootmem(struct page *page)
  62 {
  63 }
  64
  65 static inline enum bootmem_type bootmem_type(const struct page *page)
  66 {
  67         return SECTION_INFO;
  68 }
  69
  70 static inline unsigned long bootmem_info(const struct page *page)
  71 {
  72         return 0;
  73 }
  74
  75 static inline void get_page_bootmem(unsigned long info, struct page *page,
  76                                     enum bootmem_type type)
  77 {
  78 }
  79
  80 static inline void free_bootmem_page(struct page *page)
  81 {
  82         kmemleak_free_part_phys(PFN_PHYS(page_to_pfn(page)), PAGE_SIZE);
  83         free_reserved_page(page);
  84 }
  85 #endif
  86
  87 #endif /* __LINUX_BOOTMEM_INFO_H */