summaryrefslogtreecommitdiffstats
path: root/arch/x86/include/asm/mmu_context.h
blob: 52948df9cd1da52955cca670469800598319314f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
#ifndef _ASM_X86_MMU_CONTEXT_H
#define _ASM_X86_MMU_CONTEXT_H

#include <asm/desc.h>
#include <asm/atomic.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include <asm/paravirt.h>
#ifndef CONFIG_PARAVIRT
#include <asm-generic/mm_hooks.h>

static inline void paravirt_activate_mm(struct mm_struct *prev,
					struct mm_struct *next)
{
}
#endif	/* !CONFIG_PARAVIRT */

/*
 * Used for LDT copy/destruction.
 */
int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
void destroy_context(struct mm_struct *mm);


static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
#ifdef CONFIG_SMP
	if (percpu_read(cpu_tlbstate.state) == TLBSTATE_OK)
		percpu_write(cpu_tlbstate.state, TLBSTATE_LAZY);
#endif
}

static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
			     struct task_struct *tsk)
{
	unsigned cpu = smp_processor_id();

	if (likely(prev != next)) {
		/* stop flush ipis for the previous mm */
		cpu_clear(cpu, prev->cpu_vm_mask);
#ifdef CONFIG_SMP
		percpu_write(cpu_tlbstate.state, TLBSTATE_OK);
		percpu_write(cpu_tlbstate.active_mm, next);
#endif
		cpu_set(cpu, next->cpu_vm_mask);

		/* Re-load page tables */
		load_cr3(next->pgd);

		/*
		 * load the LDT, if the LDT is different:
		 */
		if (unlikely(prev->context.ldt != next->context.ldt))
			load_LDT_nolock(&next->context);
	}
#ifdef CONFIG_SMP
	else {
		percpu_write(cpu_tlbstate.state, TLBSTATE_OK);
		BUG_ON(percpu_read(cpu_tlbstate.active_mm) != next);

		if (!cpu_test_and_set(cpu, next->cpu_vm_mask)) {
			/* We were in lazy tlb mode and leave_mm disabled
			 * tlb flush IPI delivery. We must reload CR3
			 * to make sure to use no freed page tables.
			 */
			load_cr3(next->pgd);
			load_LDT_nolock(&next->context);
		}
	}
#endif
}

#define activate_mm(prev, next)			\
do {						\
	paravirt_activate_mm((prev), (next));	\
	switch_mm((prev), (next), NULL);	\
} while (0);

#ifdef CONFIG_X86_32
#define deactivate_mm(tsk, mm)			\
do {						\
	loadsegment(gs, 0);			\
} while (0)
#else
#define deactivate_mm(tsk, mm)			\
do {						\
	load_gs_index(0);			\
	loadsegment(fs, 0);			\
} while (0)
#endif

#endif /* _ASM_X86_MMU_CONTEXT_H */
OpenPOWER on IntegriCloud