bcachefs-tools/include/linux/page.h

#ifndef _LINUX_PAGE_H
#define _LINUX_PAGE_H

#include <sys/user.h>

struct page;

#ifndef PAGE_SIZE

#define PAGE_SIZE   4096UL
#define PAGE_MASK   (~(PAGE_SIZE - 1))

#endif

#ifndef PAGE_SHIFT
#define PAGE_SHIFT 12
#endif


#define virt_to_page(p)							\
	((struct page *) (((unsigned long) (p)) & PAGE_MASK))
#define offset_in_page(p)		((unsigned long) (p) & ~PAGE_MASK)

#define page_address(p)			((void *) (p))

#define kmap_atomic(page)		page_address(page)
#define kunmap_atomic(addr)		do {} while (0)

#define kmap_local_page(page)		page_address(page)
#define kunmap_local(addr)		do {} while (0)

#define PageHighMem(page)		false

static const char zero_page[PAGE_SIZE];

#define ZERO_PAGE(o)			((struct page *) &zero_page[0])

#endif /* _LINUX_PAGE_H */