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
22 #if defined(CONFIG_IDLE_PAGE_TRACKING) && !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 void pgdat_page_ext_init(struct pglist_data *pgdat);
41 #ifdef CONFIG_SPARSEMEM
42 static inline void page_ext_init_flatmem(void)
45 extern void page_ext_init(void);
47 extern void page_ext_init_flatmem(void);
48 static inline void page_ext_init(void)
53 struct page_ext *lookup_page_ext(const struct page *page);
55 #else /* !CONFIG_PAGE_EXTENSION */
58 static inline void pgdat_page_ext_init(struct pglist_data *pgdat)
62 static inline struct page_ext *lookup_page_ext(const struct page *page)
67 static inline void page_ext_init(void)
71 static inline void page_ext_init_flatmem(void)
74 #endif /* CONFIG_PAGE_EXTENSION */
75 #endif /* __LINUX_PAGE_EXT_H */