/* SPDX-License-Identifier: GPL-2.0 */
|
#ifndef __LINUX_PAGE_EXT_H
|
#define __LINUX_PAGE_EXT_H
|
|
#include <linux/types.h>
|
#include <linux/stacktrace.h>
|
#include <linux/stackdepot.h>
|
|
struct pglist_data;
|
struct page_ext_operations {
|
size_t offset;
|
size_t size;
|
bool (*need)(void);
|
void (*init)(void);
|
};
|
|
#ifdef CONFIG_PAGE_EXTENSION
|
|
enum page_ext_flags {
|
PAGE_EXT_DEBUG_GUARD,
|
PAGE_EXT_OWNER,
|
#if defined(CONFIG_IDLE_PAGE_TRACKING) && !defined(CONFIG_64BIT)
|
PAGE_EXT_YOUNG,
|
PAGE_EXT_IDLE,
|
#endif
|
};
|
|
/*
|
* Page Extension can be considered as an extended mem_map.
|
* A page_ext page is associated with every page descriptor. The
|
* page_ext helps us add more information about the page.
|
* All page_ext are allocated at boot or memory hotplug event,
|
* then the page_ext for pfn always exists.
|
*/
|
struct page_ext {
|
unsigned long flags;
|
};
|
|
extern void pgdat_page_ext_init(struct pglist_data *pgdat);
|
|
#ifdef CONFIG_SPARSEMEM
|
static inline void page_ext_init_flatmem(void)
|
{
|
}
|
extern void page_ext_init(void);
|
#else
|
extern void page_ext_init_flatmem(void);
|
static inline void page_ext_init(void)
|
{
|
}
|
#endif
|
|
struct page_ext *lookup_page_ext(const struct page *page);
|
|
#else /* !CONFIG_PAGE_EXTENSION */
|
struct page_ext;
|
|
static inline void pgdat_page_ext_init(struct pglist_data *pgdat)
|
{
|
}
|
|
static inline struct page_ext *lookup_page_ext(const struct page *page)
|
{
|
return NULL;
|
}
|
|
static inline void page_ext_init(void)
|
{
|
}
|
|
static inline void page_ext_init_flatmem(void)
|
{
|
}
|
#endif /* CONFIG_PAGE_EXTENSION */
|
#endif /* __LINUX_PAGE_EXT_H */
|
