81 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			81 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| #ifndef __PARISC_MMU_CONTEXT_H
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| #define __PARISC_MMU_CONTEXT_H
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| 
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| #include <linux/mm.h>
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| #include <linux/sched.h>
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| #include <asm/atomic.h>
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| #include <asm/pgalloc.h>
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| #include <asm/pgtable.h>
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| #include <asm-generic/mm_hooks.h>
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| 
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| static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
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| {
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| }
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| 
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| /* on PA-RISC, we actually have enough contexts to justify an allocator
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|  * for them.  prumpf */
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| 
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| extern unsigned long alloc_sid(void);
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| extern void free_sid(unsigned long);
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| 
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| static inline int
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| init_new_context(struct task_struct *tsk, struct mm_struct *mm)
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| {
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| 	BUG_ON(atomic_read(&mm->mm_users) != 1);
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| 
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| 	mm->context = alloc_sid();
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| 	return 0;
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| }
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| 
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| static inline void
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| destroy_context(struct mm_struct *mm)
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| {
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| 	free_sid(mm->context);
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| 	mm->context = 0;
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| }
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| 
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| static inline unsigned long __space_to_prot(mm_context_t context)
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| {
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| #if SPACEID_SHIFT == 0
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| 	return context << 1;
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| #else
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| 	return context >> (SPACEID_SHIFT - 1);
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| #endif
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| }
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| 
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| static inline void load_context(mm_context_t context)
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| {
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| 	mtsp(context, 3);
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| 	mtctl(__space_to_prot(context), 8);
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| }
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| 
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| static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, struct task_struct *tsk)
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| {
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| 
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| 	if (prev != next) {
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| 		mtctl(__pa(next->pgd), 25);
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| 		load_context(next->context);
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| 	}
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| }
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| 
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| #define deactivate_mm(tsk,mm)	do { } while (0)
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| 
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| static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
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| {
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| 	/*
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| 	 * Activate_mm is our one chance to allocate a space id
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| 	 * for a new mm created in the exec path. There's also
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| 	 * some lazy tlb stuff, which is currently dead code, but
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| 	 * we only allocate a space id if one hasn't been allocated
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| 	 * already, so we should be OK.
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| 	 */
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| 
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| 	BUG_ON(next == &init_mm); /* Should never happen */
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| 
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| 	if (next->context == 0)
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| 	    next->context = alloc_sid();
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| 
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| 	switch_mm(prev,next,current);
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| }
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| #endif
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