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#ifndef __X86_64_MMU_CONTEXT_H
#define __X86_64_MMU_CONTEXT_H
#include <linux/config.h>
#include <asm/desc.h>
#include <asm/atomic.h>
#include <asm/pgalloc.h>
#include <asm/pda.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
/*
* possibly do the LDT unload here?
*/
int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
void destroy_context(struct mm_struct *mm);
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
{
#ifdef CONFIG_SMP
if (read_pda(mmu_state) == TLBSTATE_OK)
write_pda(mmu_state, TLBSTATE_LAZY);
#endif
}
static inline void load_cr3(pgd_t *pgd)
{
asm volatile("movq %0,%%cr3" :: "r" (__pa(pgd)) : "memory");
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
unsigned cpu = smp_processor_id();
if (likely(prev != next)) {
/* stop flush ipis for the previous mm */
clear_bit(cpu, &prev->cpu_vm_mask);
#ifdef CONFIG_SMP
write_pda(mmu_state, TLBSTATE_OK);
write_pda(active_mm, next);
#endif
set_bit(cpu, &next->cpu_vm_mask);
load_cr3(next->pgd);
if (unlikely(next->context.ldt != prev->context.ldt))
load_LDT_nolock(&next->context, cpu);
}
#ifdef CONFIG_SMP
else {
write_pda(mmu_state, TLBSTATE_OK);
if (read_pda(active_mm) != next)
out_of_line_bug();
if(!test_and_set_bit(cpu, &next->cpu_vm_mask)) {
/* We were in lazy tlb mode and leave_mm disabled
* tlb flush IPI delivery. We must reload CR3
* to make sure to use no freed page tables.
*/
load_cr3(next->pgd);
load_LDT_nolock(&next->context, cpu);
}
}
#endif
}
#define deactivate_mm(tsk,mm) do { \
load_gs_index(0); \
asm volatile("movl %0,%%fs"::"r"(0)); \
} while(0)
#define activate_mm(prev, next) \
switch_mm((prev),(next),NULL)
#endif
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