1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_MM_TYPES_TASK_H
3#define _LINUX_MM_TYPES_TASK_H
4
5/*
6 * Here are the definitions of the MM data types that are embedded in 'struct task_struct'.
7 *
8 * (These are defined separately to decouple sched.h from mm_types.h as much as possible.)
9 */
10
11#include <linux/types.h>
12
13#include <asm/page.h>
14
15#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
16#include <asm/tlbbatch.h>
17#endif
18
19#define USE_SPLIT_PTE_PTLOCKS	(NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
20#define USE_SPLIT_PMD_PTLOCKS	(USE_SPLIT_PTE_PTLOCKS && \
21		IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK))
22#define ALLOC_SPLIT_PTLOCKS	(SPINLOCK_SIZE > BITS_PER_LONG/8)
23
24/*
25 * When updating this, please also update struct resident_page_types[] in
26 * kernel/fork.c
27 */
28enum {
29	MM_FILEPAGES,	/* Resident file mapping pages */
30	MM_ANONPAGES,	/* Resident anonymous pages */
31	MM_SWAPENTS,	/* Anonymous swap entries */
32	MM_SHMEMPAGES,	/* Resident shared memory pages */
33	NR_MM_COUNTERS
34};
35
36struct page;
37
38struct page_frag {
39	struct page *page;
40#if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
41	__u32 offset;
42	__u32 size;
43#else
44	__u16 offset;
45	__u16 size;
46#endif
47};
48
49/* Track pages that require TLB flushes */
50struct tlbflush_unmap_batch {
51#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
52	/*
53	 * The arch code makes the following promise: generic code can modify a
54	 * PTE, then call arch_tlbbatch_add_pending() (which internally provides
55	 * all needed barriers), then call arch_tlbbatch_flush(), and the entries
56	 * will be flushed on all CPUs by the time that arch_tlbbatch_flush()
57	 * returns.
58	 */
59	struct arch_tlbflush_unmap_batch arch;
60
61	/* True if a flush is needed. */
62	bool flush_required;
63
64	/*
65	 * If true then the PTE was dirty when unmapped. The entry must be
66	 * flushed before IO is initiated or a stale TLB entry potentially
67	 * allows an update without redirtying the page.
68	 */
69	bool writable;
70#endif
71};
72
73#endif /* _LINUX_MM_TYPES_TASK_H */
74