1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_PAGE_EXT_H
3 #define __LINUX_PAGE_EXT_H
5 #include <linux/types.h>
6 #include <linux/stacktrace.h>
7 #include <linux/stackdepot.h>
10 struct page_ext_operations {
17 #ifdef CONFIG_PAGE_EXTENSION
21 PAGE_EXT_OWNER_ALLOCATED,
22 #if defined(CONFIG_PAGE_IDLE_FLAG) && !defined(CONFIG_64BIT)
29 * Page Extension can be considered as an extended mem_map.
30 * A page_ext page is associated with every page descriptor. The
31 * page_ext helps us add more information about the page.
32 * All page_ext are allocated at boot or memory hotplug event,
33 * then the page_ext for pfn always exists.
39 extern bool early_page_ext;
40 extern unsigned long page_ext_size;
41 extern void pgdat_page_ext_init(struct pglist_data *pgdat);
43 static inline bool early_page_ext_enabled(void)
45 return early_page_ext;
48 #ifdef CONFIG_SPARSEMEM
49 static inline void page_ext_init_flatmem(void)
52 extern void page_ext_init(void);
53 static inline void page_ext_init_flatmem_late(void)
57 extern void page_ext_init_flatmem(void);
58 extern void page_ext_init_flatmem_late(void);
59 static inline void page_ext_init(void)
64 extern struct page_ext *page_ext_get(struct page *page);
65 extern void page_ext_put(struct page_ext *page_ext);
67 static inline struct page_ext *page_ext_next(struct page_ext *curr)
70 next += page_ext_size;
74 #else /* !CONFIG_PAGE_EXTENSION */
77 static inline bool early_page_ext_enabled(void)
82 static inline void pgdat_page_ext_init(struct pglist_data *pgdat)
86 static inline void page_ext_init(void)
90 static inline void page_ext_init_flatmem_late(void)
94 static inline void page_ext_init_flatmem(void)
98 static inline struct page_ext *page_ext_get(struct page *page)
103 static inline void page_ext_put(struct page_ext *page_ext)
106 #endif /* CONFIG_PAGE_EXTENSION */
107 #endif /* __LINUX_PAGE_EXT_H */