diff options
Diffstat (limited to 'arch/arm/include/asm/mmu_context.h')
-rw-r--r-- | arch/arm/include/asm/mmu_context.h | 82 |
1 files changed, 3 insertions, 79 deletions
diff --git a/arch/arm/include/asm/mmu_context.h b/arch/arm/include/asm/mmu_context.h index 0306bc642c0d..a64f61cb23d1 100644 --- a/arch/arm/include/asm/mmu_context.h +++ b/arch/arm/include/asm/mmu_context.h | |||
@@ -24,84 +24,8 @@ void __check_kvm_seq(struct mm_struct *mm); | |||
24 | 24 | ||
25 | #ifdef CONFIG_CPU_HAS_ASID | 25 | #ifdef CONFIG_CPU_HAS_ASID |
26 | 26 | ||
27 | /* | 27 | void check_and_switch_context(struct mm_struct *mm, struct task_struct *tsk); |
28 | * On ARMv6, we have the following structure in the Context ID: | 28 | #define init_new_context(tsk,mm) ({ mm->context.id = 0; }) |
29 | * | ||
30 | * 31 7 0 | ||
31 | * +-------------------------+-----------+ | ||
32 | * | process ID | ASID | | ||
33 | * +-------------------------+-----------+ | ||
34 | * | context ID | | ||
35 | * +-------------------------------------+ | ||
36 | * | ||
37 | * The ASID is used to tag entries in the CPU caches and TLBs. | ||
38 | * The context ID is used by debuggers and trace logic, and | ||
39 | * should be unique within all running processes. | ||
40 | */ | ||
41 | #define ASID_BITS 8 | ||
42 | #define ASID_MASK ((~0) << ASID_BITS) | ||
43 | #define ASID_FIRST_VERSION (1 << ASID_BITS) | ||
44 | |||
45 | extern unsigned int cpu_last_asid; | ||
46 | |||
47 | void __init_new_context(struct task_struct *tsk, struct mm_struct *mm); | ||
48 | void __new_context(struct mm_struct *mm); | ||
49 | void cpu_set_reserved_ttbr0(void); | ||
50 | |||
51 | static inline void switch_new_context(struct mm_struct *mm) | ||
52 | { | ||
53 | unsigned long flags; | ||
54 | |||
55 | __new_context(mm); | ||
56 | |||
57 | local_irq_save(flags); | ||
58 | cpu_switch_mm(mm->pgd, mm); | ||
59 | local_irq_restore(flags); | ||
60 | } | ||
61 | |||
62 | static inline void check_and_switch_context(struct mm_struct *mm, | ||
63 | struct task_struct *tsk) | ||
64 | { | ||
65 | if (unlikely(mm->context.kvm_seq != init_mm.context.kvm_seq)) | ||
66 | __check_kvm_seq(mm); | ||
67 | |||
68 | /* | ||
69 | * Required during context switch to avoid speculative page table | ||
70 | * walking with the wrong TTBR. | ||
71 | */ | ||
72 | cpu_set_reserved_ttbr0(); | ||
73 | |||
74 | if (!((mm->context.id ^ cpu_last_asid) >> ASID_BITS)) | ||
75 | /* | ||
76 | * The ASID is from the current generation, just switch to the | ||
77 | * new pgd. This condition is only true for calls from | ||
78 | * context_switch() and interrupts are already disabled. | ||
79 | */ | ||
80 | cpu_switch_mm(mm->pgd, mm); | ||
81 | else if (irqs_disabled()) | ||
82 | /* | ||
83 | * Defer the new ASID allocation until after the context | ||
84 | * switch critical region since __new_context() cannot be | ||
85 | * called with interrupts disabled (it sends IPIs). | ||
86 | */ | ||
87 | set_ti_thread_flag(task_thread_info(tsk), TIF_SWITCH_MM); | ||
88 | else | ||
89 | /* | ||
90 | * That is a direct call to switch_mm() or activate_mm() with | ||
91 | * interrupts enabled and a new context. | ||
92 | */ | ||
93 | switch_new_context(mm); | ||
94 | } | ||
95 | |||
96 | #define init_new_context(tsk,mm) (__init_new_context(tsk,mm),0) | ||
97 | |||
98 | #define finish_arch_post_lock_switch \ | ||
99 | finish_arch_post_lock_switch | ||
100 | static inline void finish_arch_post_lock_switch(void) | ||
101 | { | ||
102 | if (test_and_clear_thread_flag(TIF_SWITCH_MM)) | ||
103 | switch_new_context(current->mm); | ||
104 | } | ||
105 | 29 | ||
106 | #else /* !CONFIG_CPU_HAS_ASID */ | 30 | #else /* !CONFIG_CPU_HAS_ASID */ |
107 | 31 | ||
@@ -143,6 +67,7 @@ static inline void finish_arch_post_lock_switch(void) | |||
143 | #endif /* CONFIG_CPU_HAS_ASID */ | 67 | #endif /* CONFIG_CPU_HAS_ASID */ |
144 | 68 | ||
145 | #define destroy_context(mm) do { } while(0) | 69 | #define destroy_context(mm) do { } while(0) |
70 | #define activate_mm(prev,next) switch_mm(prev, next, NULL) | ||
146 | 71 | ||
147 | /* | 72 | /* |
148 | * This is called when "tsk" is about to enter lazy TLB mode. | 73 | * This is called when "tsk" is about to enter lazy TLB mode. |
@@ -186,6 +111,5 @@ switch_mm(struct mm_struct *prev, struct mm_struct *next, | |||
186 | } | 111 | } |
187 | 112 | ||
188 | #define deactivate_mm(tsk,mm) do { } while (0) | 113 | #define deactivate_mm(tsk,mm) do { } while (0) |
189 | #define activate_mm(prev,next) switch_mm(prev, next, NULL) | ||
190 | 114 | ||
191 | #endif | 115 | #endif |