1 #ifndef _ASM_X86_MMU_CONTEXT_H 2 #define _ASM_X86_MMU_CONTEXT_H 3 4 #include <asm/desc.h> 5 #include <linux/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 (this_cpu_read(cpu_tlbstate.state) == TLBSTATE_OK) 29 this_cpu_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 this_cpu_write(cpu_tlbstate.state, TLBSTATE_OK); 41 this_cpu_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 /* Load the LDT, if the LDT is different: */ 52 if (unlikely(prev->context.ldt != next->context.ldt)) 53 load_LDT_nolock(&next->context); 54 } 55 #ifdef CONFIG_SMP 56 else { 57 this_cpu_write(cpu_tlbstate.state, TLBSTATE_OK); 58 BUG_ON(this_cpu_read(cpu_tlbstate.active_mm) != next); 59 60 if (!cpumask_test_cpu(cpu, mm_cpumask(next))) { 61 /* 62 * On established mms, the mm_cpumask is only changed 63 * from irq context, from ptep_clear_flush() while in 64 * lazy tlb mode, and here. Irqs are blocked during 65 * schedule, protecting us from simultaneous changes. 66 */ 67 cpumask_set_cpu(cpu, mm_cpumask(next)); 68 /* 69 * We were in lazy tlb mode and leave_mm disabled 70 * tlb flush IPI delivery. We must reload CR3 71 * to make sure to use no freed page tables. 72 */ 73 load_cr3(next->pgd); 74 load_LDT_nolock(&next->context); 75 } 76 } 77 #endif 78 } 79 80 #define activate_mm(prev, next) \ 81 do { \ 82 paravirt_activate_mm((prev), (next)); \ 83 switch_mm((prev), (next), NULL); \ 84 } while (0); 85 86 #ifdef CONFIG_X86_32 87 #define deactivate_mm(tsk, mm) \ 88 do { \ 89 lazy_load_gs(0); \ 90 } while (0) 91 #else 92 #define deactivate_mm(tsk, mm) \ 93 do { \ 94 load_gs_index(0); \ 95 loadsegment(fs, 0); \ 96 } while (0) 97 #endif 98 99 #endif /* _ASM_X86_MMU_CONTEXT_H */ 100