Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-2.6.git] / arch / x86 / include / asm / mmu_context.h
1 #ifndef _ASM_X86_MMU_CONTEXT_H
2 #define _ASM_X86_MMU_CONTEXT_H
3
4 #include <asm/desc.h>
5 #include <asm/atomic.h>
6 #include <asm/pgalloc.h>
7 #include <asm/tlbflush.h>
8 #include <asm/paravirt.h>
9 #ifndef CONFIG_PARAVIRT
10 #include <asm-generic/mm_hooks.h>
11
12 static inline void paravirt_activate_mm(struct mm_struct *prev,
13                                         struct mm_struct *next)
14 {
15 }
16 #endif  /* !CONFIG_PARAVIRT */
17
18 /*
19  * Used for LDT copy/destruction.
20  */
21 int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
22 void destroy_context(struct mm_struct *mm);
23
24
25 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
26 {
27 #ifdef CONFIG_SMP
28         if (percpu_read(cpu_tlbstate.state) == TLBSTATE_OK)
29                 percpu_write(cpu_tlbstate.state, TLBSTATE_LAZY);
30 #endif
31 }
32
33 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
34                              struct task_struct *tsk)
35 {
36         unsigned cpu = smp_processor_id();
37
38         if (likely(prev != next)) {
39 #ifdef CONFIG_SMP
40                 percpu_write(cpu_tlbstate.state, TLBSTATE_OK);
41                 percpu_write(cpu_tlbstate.active_mm, next);
42 #endif
43                 cpumask_set_cpu(cpu, mm_cpumask(next));
44
45                 /* Re-load page tables */
46                 load_cr3(next->pgd);
47
48                 /* stop flush ipis for the previous mm */
49                 cpumask_clear_cpu(cpu, mm_cpumask(prev));
50
51                 /*
52                  * load the LDT, if the LDT is different:
53                  */
54                 if (unlikely(prev->context.ldt != next->context.ldt))
55                         load_LDT_nolock(&next->context);
56         }
57 #ifdef CONFIG_SMP
58         else {
59                 percpu_write(cpu_tlbstate.state, TLBSTATE_OK);
60                 BUG_ON(percpu_read(cpu_tlbstate.active_mm) != next);
61
62                 if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next))) {
63                         /* We were in lazy tlb mode and leave_mm disabled
64                          * tlb flush IPI delivery. We must reload CR3
65                          * to make sure to use no freed page tables.
66                          */
67                         load_cr3(next->pgd);
68                         load_LDT_nolock(&next->context);
69                 }
70         }
71 #endif
72 }
73
74 #define activate_mm(prev, next)                 \
75 do {                                            \
76         paravirt_activate_mm((prev), (next));   \
77         switch_mm((prev), (next), NULL);        \
78 } while (0);
79
80 #ifdef CONFIG_X86_32
81 #define deactivate_mm(tsk, mm)                  \
82 do {                                            \
83         lazy_load_gs(0);                        \
84 } while (0)
85 #else
86 #define deactivate_mm(tsk, mm)                  \
87 do {                                            \
88         load_gs_index(0);                       \
89         loadsegment(fs, 0);                     \
90 } while (0)
91 #endif
92
93 #endif /* _ASM_X86_MMU_CONTEXT_H */