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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef __X86_64_MMU_CONTEXT_H
2#define __X86_64_MMU_CONTEXT_H
3
4#include <asm/desc.h>
5#include <asm/atomic.h>
6#include <asm/pgalloc.h>
7#include <asm/pda.h>
8#include <asm/pgtable.h>
9#include <asm/tlbflush.h>
10#ifndef CONFIG_PARAVIRT
11#include <asm-generic/mm_hooks.h>
12#endif
13
14/*
15 * possibly do the LDT unload here?
16 */
17int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
18void destroy_context(struct mm_struct *mm);
19
20static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
21{
22#ifdef CONFIG_SMP
23 if (read_pda(mmu_state) == TLBSTATE_OK)
24 write_pda(mmu_state, TLBSTATE_LAZY);
25#endif
26}
27
28static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
29 struct task_struct *tsk)
30{
31 unsigned cpu = smp_processor_id();
32 if (likely(prev != next)) {
33 /* stop flush ipis for the previous mm */
34 cpu_clear(cpu, prev->cpu_vm_mask);
35#ifdef CONFIG_SMP
36 write_pda(mmu_state, TLBSTATE_OK);
37 write_pda(active_mm, next);
38#endif
39 cpu_set(cpu, next->cpu_vm_mask);
40 load_cr3(next->pgd);
41
42 if (unlikely(next->context.ldt != prev->context.ldt))
43 load_LDT_nolock(&next->context);
44 }
45#ifdef CONFIG_SMP
46 else {
47 write_pda(mmu_state, TLBSTATE_OK);
48 if (read_pda(active_mm) != next)
49 BUG();
50 if (!cpu_test_and_set(cpu, next->cpu_vm_mask)) {
51 /* We were in lazy tlb mode and leave_mm disabled
52 * tlb flush IPI delivery. We must reload CR3
53 * to make sure to use no freed page tables.
54 */
55 load_cr3(next->pgd);
56 load_LDT_nolock(&next->context);
57 }
58 }
59#endif
60}
61
62#define deactivate_mm(tsk,mm) do { \
63 load_gs_index(0); \
64 asm volatile("movl %0,%%fs"::"r"(0)); \
65} while(0)
66
67#define activate_mm(prev, next) \
68 switch_mm((prev),(next),NULL)
69
70
71#endif