linux/include/linux/pageblock-flags.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Macros for manipulating and testing flags related to a
 * pageblock_nr_pages number of pages.
 *
 * Copyright (C) IBM Corporation, 2006
 *
 * Original author, Mel Gorman
 * Major cleanups and reduction of bit operations, Andy Whitcroft
 */
#ifndef PAGEBLOCK_FLAGS_H
#define PAGEBLOCK_FLAGS_H

#include <linux/types.h>

#define PB_migratetype_bits …
/* Bit indices that affect a whole block of pages */
enum pageblock_bits { … };

#if defined(CONFIG_HUGETLB_PAGE)

#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE

/* Huge page sizes are variable */
extern unsigned int pageblock_order;

#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */

/*
 * Huge pages are a constant size, but don't exceed the maximum allocation
 * granularity.
 */
#define pageblock_order …

#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */

#elif defined(CONFIG_TRANSPARENT_HUGEPAGE)

#define pageblock_order …

#else /* CONFIG_TRANSPARENT_HUGEPAGE */

/* If huge pages are not used, group by MAX_ORDER_NR_PAGES */
#define pageblock_order …

#endif /* CONFIG_HUGETLB_PAGE */

#define pageblock_nr_pages …
#define pageblock_align(pfn) …
#define pageblock_aligned(pfn) …
#define pageblock_start_pfn(pfn) …
#define pageblock_end_pfn(pfn) …

/* Forward declaration */
struct page;

unsigned long get_pfnblock_flags_mask(const struct page *page,
				unsigned long pfn,
				unsigned long mask);

void set_pfnblock_flags_mask(struct page *page,
				unsigned long flags,
				unsigned long pfn,
				unsigned long mask);

/* Declarations for getting and setting flags. See mm/page_alloc.c */
#ifdef CONFIG_COMPACTION
#define get_pageblock_skip(page) …
#define clear_pageblock_skip(page) …
#define set_pageblock_skip(page) …
#else
static inline bool get_pageblock_skip(struct page *page)
{
	return false;
}
static inline void clear_pageblock_skip(struct page *page)
{
}
static inline void set_pageblock_skip(struct page *page)
{
}
#endif /* CONFIG_COMPACTION */

#endif	/* PAGEBLOCK_FLAGS_H */