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 #include <linux/threads.h>
13 #include <linux/atomic.h>
14 #include <linux/cpumask.h>
15 
16 #include <asm/page.h>
17 
18 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
19 #include <asm/tlbbatch.h>
20 #endif
21 
22 #define USE_SPLIT_PTE_PTLOCKS	(NR_CPUS >= CONFIG_SPLIT_PTLOCK_CPUS)
23 #define USE_SPLIT_PMD_PTLOCKS	(USE_SPLIT_PTE_PTLOCKS && \
24 		IS_ENABLED(CONFIG_ARCH_ENABLE_SPLIT_PMD_PTLOCK))
25 #define ALLOC_SPLIT_PTLOCKS	(SPINLOCK_SIZE > BITS_PER_LONG/8)
26 
27 /*
28  * When updating this, please also update struct resident_page_types[] in
29  * kernel/fork.c
30  */
31 enum {
32 	MM_FILEPAGES,	/* Resident file mapping pages */
33 	MM_ANONPAGES,	/* Resident anonymous pages */
34 	MM_SWAPENTS,	/* Anonymous swap entries */
35 	MM_SHMEMPAGES,	/* Resident shared memory pages */
36 	NR_MM_COUNTERS
37 };
38 
39 struct page_frag {
40 	struct page *page;
41 #if (BITS_PER_LONG > 32) || (PAGE_SIZE >= 65536)
42 	__u32 offset;
43 	__u32 size;
44 #else
45 	__u16 offset;
46 	__u16 size;
47 #endif
48 };
49 
50 /* Track pages that require TLB flushes */
51 struct tlbflush_unmap_batch {
52 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
53 	/*
54 	 * The arch code makes the following promise: generic code can modify a
55 	 * PTE, then call arch_tlbbatch_add_pending() (which internally provides
56 	 * all needed barriers), then call arch_tlbbatch_flush(), and the entries
57 	 * will be flushed on all CPUs by the time that arch_tlbbatch_flush()
58 	 * returns.
59 	 */
60 	struct arch_tlbflush_unmap_batch arch;
61 
62 	/* True if a flush is needed. */
63 	bool flush_required;
64 
65 	/*
66 	 * If true then the PTE was dirty when unmapped. The entry must be
67 	 * flushed before IO is initiated or a stale TLB entry potentially
68 	 * allows an update without redirtying the page.
69 	 */
70 	bool writable;
71 #endif
72 };
73 
74 #endif /* _LINUX_MM_TYPES_TASK_H */
75