1 #ifndef __I386_MMU_CONTEXT_H
2 #define __I386_MMU_CONTEXT_H
3 
4 #include <linux/config.h>
5 #include <asm/desc.h>
6 #include <asm/atomic.h>
7 #include <asm/pgalloc.h>
8 
9 /*
10  * hooks to add arch specific data into the mm struct.
11  * Note that destroy_context is called even if init_new_context
12  * fails.
13  */
14 int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
15 void destroy_context(struct mm_struct *mm);
16 
17 #ifdef CONFIG_SMP
18 
enter_lazy_tlb(struct mm_struct * mm,struct task_struct * tsk,unsigned cpu)19 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk, unsigned cpu)
20 {
21 	if(cpu_tlbstate[cpu].state == TLBSTATE_OK)
22 		cpu_tlbstate[cpu].state = TLBSTATE_LAZY;
23 }
24 #else
enter_lazy_tlb(struct mm_struct * mm,struct task_struct * tsk,unsigned cpu)25 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk, unsigned cpu)
26 {
27 }
28 #endif
29 
switch_mm(struct mm_struct * prev,struct mm_struct * next,struct task_struct * tsk,unsigned cpu)30 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk, unsigned cpu)
31 {
32 	if (prev != next) {
33 		/* stop flush ipis for the previous mm */
34 		clear_bit(cpu, &prev->cpu_vm_mask);
35 #ifdef CONFIG_SMP
36 		cpu_tlbstate[cpu].state = TLBSTATE_OK;
37 		cpu_tlbstate[cpu].active_mm = next;
38 #endif
39 		set_bit(cpu, &next->cpu_vm_mask);
40 		/* Re-load page tables */
41 		load_cr3(next->pgd);
42 	 	/* load_LDT, if either the previous or next thread
43 		 * has a non-default LDT.
44 		 */
45 		if (next->context.size+prev->context.size)
46 			load_LDT(&next->context);
47 	}
48 #ifdef CONFIG_SMP
49 	else {
50 		cpu_tlbstate[cpu].state = TLBSTATE_OK;
51 		if(cpu_tlbstate[cpu].active_mm != next)
52 			out_of_line_bug();
53 		if(!test_and_set_bit(cpu, &next->cpu_vm_mask)) {
54 			/* We were in lazy tlb mode and leave_mm disabled
55 			 * tlb flush IPI delivery. We must reload %cr3.
56 			 */
57 			load_cr3(next->pgd);
58 			load_LDT(&next->context);
59 		}
60 	}
61 #endif
62 }
63 
64 #define activate_mm(prev, next) \
65 	switch_mm((prev),(next),NULL,smp_processor_id())
66 
67 #endif
68