/* SPDX-License-Identifier: GPL-2.0-or-later */
/* internal.h: mm/ internal definitions
*
* Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#ifndef __MM_INTERNAL_H
#define __MM_INTERNAL_H
#include <linux/fs.h>
#include <linux/khugepaged.h>
#include <linux/mm.h>
#include <linux/mm_inline.h>
#include <linux/pagemap.h>
#include <linux/rmap.h>
#include <linux/swap.h>
#include <linux/swapops.h>
#include <linux/swap_cgroup.h>
#include <linux/tracepoint-defs.h>
/* Internal core VMA manipulation functions. */
#include "vma.h"
struct folio_batch;
/*
* The set of flags that only affect watermark checking and reclaim
* behaviour. This is used by the MM to obey the caller constraints
* about IO, FS and watermark checking while ignoring placement
* hints such as HIGHMEM usage.
*/
#define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NOFAIL|\
__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
__GFP_NOLOCKDEP)
/* The GFP flags allowed during early boot */
#define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
/* Control allocation cpuset and node placement constraints */
#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
/* Do not use these with a slab allocator */
#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
/*
* Different from WARN_ON_ONCE(), no warning will be issued
* when we specify __GFP_NOWARN.
*/
#define WARN_ON_ONCE_GFP(cond, gfp) ({ \
static bool __section(".data.once") __warned; \
int __ret_warn_once = !!(cond); \
\
if (unlikely(!(gfp & __GFP_NOWARN) && __ret_warn_once && !__warned)) { \
__warned = true; \
WARN_ON(1); \
} \
unlikely(__ret_warn_once); \
})
void page_writeback_init(void);
/*
* If a 16GB hugetlb folio were mapped by PTEs of all of its 4kB pages,
* its nr_pages_mapped would be 0x400000: choose the ENTIRELY_MAPPED bit
* above that range, instead of 2*(PMD_SIZE/PAGE_SIZE). Hugetlb currently
* leaves nr_pages_mapped at 0, but avoid surprise if it participates later.
*/
#define ENTIRELY_MAPPED 0x800000
#define FOLIO_PAGES_MAPPED (ENTIRELY_MAPPED - 1)
/*
* Flags passed to __show_mem() and show_free_areas() to suppress output in
* various contexts.
*/
#define SHOW_MEM_FILTER_NODES (0x0001u) /* disallowed nodes */
/*
* How many individual pages have an elevated _mapcount. Excludes
* the folio's entire_mapcount.
*
* Don't use this function outside of debugging code.
*/
static inline int folio_nr_pages_mapped(const struct folio *folio)
{
return atomic_read(&folio->_nr_pages_mapped) & FOLIO_PAGES_MAPPED;
}
/*
* Retrieve the first entry of a folio based on a provided entry within the
* folio. We cannot rely on folio->swap as there is no guarantee that it has
* been initialized. Used for calling arch_swap_restore()
*/
static inline swp_entry_t folio_swap(swp_entry_t entry,
const struct folio *folio)
