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 /* stop flush ipis for the previous mm */ 40 cpu_clear(cpu, prev->cpu_vm_mask); 41 #ifdef CONFIG_SMP 42 percpu_write(cpu_tlbstate.state, TLBSTATE_OK); 43 percpu_write(cpu_tlbstate.active_mm, next); 44 #endif 45 cpu_set(cpu, next->cpu_vm_mask); 46 47 /* Re-load page tables */ 48 load_cr3(next->pgd); 49 50 /* 51 * load the LDT, if the LDT is different: 52 */ 53 if (unlikely(prev->context.ldt != next->context.ldt)) 54 load_LDT_nolock(&next->context); 55 } 56 #ifdef CONFIG_SMP 57 else { 58 percpu_write(cpu_tlbstate.state, TLBSTATE_OK); 59 BUG_ON(percpu_read(cpu_tlbstate.active_mm) != next); 60 61 if (!cpu_test_and_set(cpu, next->cpu_vm_mask)) { 62 /* We were in lazy tlb mode and leave_mm disabled 63 * tlb flush IPI delivery. We must reload CR3 64 * to make sure to use no freed page tables. 65 */ 66 load_cr3(next->pgd); 67 load_LDT_nolock(&next->context); 68 } 69 } 70 #endif 71 } 72 73 #define activate_mm(prev, next) \ 74 do { \ 75 paravirt_activate_mm((prev), (next)); \ 76 switch_mm((prev), (next), NULL); \ 77 } while (0); 78 79 #ifdef CONFIG_X86_32 80 #define deactivate_mm(tsk, mm) \ 81 do { \ 82 lazy_load_gs(0); \ 83 } while (0) 84 #else 85 #define deactivate_mm(tsk, mm) \ 86 do { \ 87 load_gs_index(0); \ 88 loadsegment(fs, 0); \ 89 } while (0) 90 #endif 91 92 #endif /* _ASM_X86_MMU_CONTEXT_H */ 93